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Lam HW, Patodia S, Zeicu C, Lim YM, Mrzyglod A, Scott C, Oliveira J, De Tisi J, Legouhy A, Zhang H, Koepp M, Diehl B, Thom M. Quantitative cellular pathology of the amygdala in temporal lobe epilepsy and correlation with magnetic resonance imaging volumetry, tissue microstructure, and sudden unexpected death in epilepsy risk factors. Epilepsia 2024. [PMID: 38837385 DOI: 10.1111/epi.18033] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/19/2024] [Revised: 05/18/2024] [Accepted: 05/20/2024] [Indexed: 06/07/2024]
Abstract
OBJECTIVE Amygdala enlargement can occur in temporal lobe epilepsy, and increased amygdala volume is also reported in sudden unexpected death in epilepsy (SUDEP). Apnea can be induced by amygdala stimulation, and postconvulsive central apnea (PCCA) and generalized seizures are both known SUDEP risk factors. Neurite orientation dispersion and density imaging (NODDI) has recently provided additional information on altered amygdala microstructure in SUDEP. In a series of 24 surgical temporal lobe epilepsy cases, our aim was to quantify amygdala cellular pathology parameters that could predict enlargement, NODDI changes, and ictal respiratory dysfunction. METHODS Using whole slide scanning automated quantitative image analysis methods, parallel evaluation of myelin, axons, dendrites, oligodendroglia, microglia, astroglia, neurons, serotonergic networks, mTOR-pathway activation (pS6) and phosphorylated tau (pTau; AT8, AT100, PHF) in amygdala, periamygdala cortex, and white matter regions of interest were compared with preoperative magnetic resonance imaging data on amygdala size, and in 13 cases with NODDI and evidence of ictal-associated apnea. RESULTS We observed significantly higher glial labeling (Iba1, glial fibrillary acidic protein, Olig2) in amygdala regions compared to cortex and a strong positive correlation between Olig2 and Iba1 in the amygdala. Larger amygdala volumes correlated with lower microtubule-associated protein (MAP2), whereas higher NODDI orientation dispersion index correlated with lower Olig2 cell densities. In the three cases with recorded PCCA, higher MAP2 and pS6-235 expression was noted than in those without. pTau did not correlate with SUDEP risk factors, including seizure frequency. SIGNIFICANCE Histological quantitation of amygdala microstructure can shed light on enlargement and diffusion imaging alterations in epilepsy to explore possible mechanisms of amygdala dysfunction, including mTOR pathway activation, that in turn may increase the risk for SUDEP.
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Affiliation(s)
- Hou Wang Lam
- Department of Clinical and Experimental Epilepsy, University College London (UCL) Queen Square Institute of Neurology, London, UK
| | - Smriti Patodia
- Department of Clinical and Experimental Epilepsy, University College London (UCL) Queen Square Institute of Neurology, London, UK
| | - Claudia Zeicu
- Department of Clinical and Experimental Epilepsy, University College London (UCL) Queen Square Institute of Neurology, London, UK
| | - Yau Mun Lim
- Division of Neuropathology, UCL Queen Square Institute of Neurology and National Hospital for Neurology and Neurosurgery, University College Hospitals NHS Foundation Trust, London, UK
| | - Alicja Mrzyglod
- Department of Clinical and Experimental Epilepsy, University College London (UCL) Queen Square Institute of Neurology, London, UK
| | - Catherine Scott
- Department of Clinical and Experimental Epilepsy, University College London (UCL) Queen Square Institute of Neurology, London, UK
- Department of Clinical Neurophysiology, National Hospital for Neurology and Neurosurgery, University College Hospitals NHS Foundation Trust, London, UK
| | - Joana Oliveira
- Department of Clinical and Experimental Epilepsy, University College London (UCL) Queen Square Institute of Neurology, London, UK
- Department of Clinical Neurophysiology, National Hospital for Neurology and Neurosurgery, University College Hospitals NHS Foundation Trust, London, UK
| | - Jane De Tisi
- Department of Clinical and Experimental Epilepsy, University College London (UCL) Queen Square Institute of Neurology, London, UK
| | - Antoine Legouhy
- Centre for Medical Image Computing, Department of Computer Science, University College London, London, UK
| | - Hui Zhang
- Centre for Medical Image Computing, Department of Computer Science, University College London, London, UK
| | - Matthias Koepp
- Department of Clinical and Experimental Epilepsy, University College London (UCL) Queen Square Institute of Neurology, London, UK
| | - Beate Diehl
- Department of Clinical and Experimental Epilepsy, University College London (UCL) Queen Square Institute of Neurology, London, UK
- Department of Clinical Neurophysiology, National Hospital for Neurology and Neurosurgery, University College Hospitals NHS Foundation Trust, London, UK
| | - Maria Thom
- Department of Clinical and Experimental Epilepsy, University College London (UCL) Queen Square Institute of Neurology, London, UK
- Division of Neuropathology, UCL Queen Square Institute of Neurology and National Hospital for Neurology and Neurosurgery, University College Hospitals NHS Foundation Trust, London, UK
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Vermeulen I, Rodriguez-Alvarez N, François L, Viot D, Poosti F, Aronica E, Dedeurwaerdere S, Barton P, Cillero-Pastor B, Heeren RMA. Spatial omics reveals molecular changes in focal cortical dysplasia type II. Neurobiol Dis 2024; 195:106491. [PMID: 38575092 DOI: 10.1016/j.nbd.2024.106491] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/14/2023] [Revised: 03/14/2024] [Accepted: 04/01/2024] [Indexed: 04/06/2024] Open
Abstract
Focal cortical dysplasia (FCD) represents a group of diverse localized cortical lesions that are highly epileptogenic and occur due to abnormal brain development caused by genetic mutations, involving the mammalian target of rapamycin (mTOR). These somatic mutations lead to mosaicism in the affected brain, posing challenges to unravel the direct and indirect functional consequences of these mutations. To comprehensively characterize the impact of mTOR mutations on the brain, we employed here a multimodal approach in a preclinical mouse model of FCD type II (Rheb), focusing on spatial omics techniques to define the proteomic and lipidomic changes. Mass Spectrometry Imaging (MSI) combined with fluorescence imaging and label free proteomics, revealed insight into the brain's lipidome and proteome within the FCD type II affected region in the mouse model. MSI visualized disrupted neuronal migration and differential lipid distribution including a reduction in sulfatides in the FCD type II-affected region, which play a role in brain myelination. MSI-guided laser capture microdissection (LMD) was conducted on FCD type II and control regions, followed by label free proteomics, revealing changes in myelination pathways by oligodendrocytes. Surgical resections of FCD type IIb and postmortem human cortex were analyzed by bulk transcriptomics to unravel the interplay between genetic mutations and molecular changes in FCD type II. Our comparative analysis of protein pathways and enriched Gene Ontology pathways related to myelination in the FCD type II-affected mouse model and human FCD type IIb transcriptomics highlights the animal model's translational value. This dual approach, including mouse model proteomics and human transcriptomics strengthens our understanding of the functional consequences arising from somatic mutations in FCD type II, as well as the identification of pathways that may be used as therapeutic strategies in the future.
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Affiliation(s)
- Isabeau Vermeulen
- Maastricht MultiModal Molecular Imaging Institute (M4i), Maastricht University, Universiteitssingel 50, 6229 ER Maastricht, the Netherlands
| | | | - Liesbeth François
- UCB Pharma, Chemin du Foriest 1, 1420 Braine-l'Alleud, Walloon Region, Belgium
| | - Delphine Viot
- UCB Pharma, Chemin du Foriest 1, 1420 Braine-l'Alleud, Walloon Region, Belgium
| | - Fariba Poosti
- UCB Pharma, Chemin du Foriest 1, 1420 Braine-l'Alleud, Walloon Region, Belgium
| | - Eleonora Aronica
- Amsterdam UMC, University of Amsterdam, Amsterdam Neuroscience, Department of (Neuro)Pathology, De Boelelaan 1108, 1081 HV Amsterdam, the Netherlands; Stichting Epilepsie Instellingen Nederland (SEIN), Achterweg 3, 2103 SW Heemstede, the Netherlands
| | | | - Patrick Barton
- UCB Pharma, 216 Bath Rd, Slough, SL1 3WE Berkshire, United Kingdom
| | - Berta Cillero-Pastor
- Maastricht MultiModal Molecular Imaging Institute (M4i), Maastricht University, Universiteitssingel 50, 6229 ER Maastricht, the Netherlands; Cell Biology-Inspired Tissue Engineering (cBITE), MERLN, Maastricht University, Universiteitssingel 40, 6229 ET Maastricht, Netherlands
| | - Ron M A Heeren
- Maastricht MultiModal Molecular Imaging Institute (M4i), Maastricht University, Universiteitssingel 50, 6229 ER Maastricht, the Netherlands.
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Ding Z, Hu S, Su TY, Choi JY, Morris S, Wang X, Sakaie K, Murakami H, Huppertz HJ, Blümcke I, Jones S, Najm I, Ma D, Wang ZI. Combining magnetic resonance fingerprinting with voxel-based morphometric analysis to reduce false positives for focal cortical dysplasia detection. Epilepsia 2024; 65:1631-1643. [PMID: 38511905 PMCID: PMC11166521 DOI: 10.1111/epi.17951] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/31/2023] [Revised: 02/09/2024] [Accepted: 03/04/2024] [Indexed: 03/22/2024]
Abstract
OBJECTIVE We aim to improve focal cortical dysplasia (FCD) detection by combining high-resolution, three-dimensional (3D) magnetic resonance fingerprinting (MRF) with voxel-based morphometric magnetic resonance imaging (MRI) analysis. METHODS We included 37 patients with pharmacoresistant focal epilepsy and FCD (10 IIa, 15 IIb, 10 mild Malformation of Cortical Development [mMCD], and 2 mMCD with oligodendroglial hyperplasia and epilepsy [MOGHE]). Fifty-nine healthy controls (HCs) were also included. 3D lesion labels were manually created. Whole-brain MRF scans were obtained with 1 mm3 isotropic resolution, from which quantitative T1 and T2 maps were reconstructed. Voxel-based MRI postprocessing, implemented with the morphometric analysis program (MAP18), was performed for FCD detection using clinical T1w images, outputting clusters with voxel-wise lesion probabilities. Average MRF T1 and T2 were calculated in each cluster from MAP18 output for gray matter (GM) and white matter (WM) separately. Normalized MRF T1 and T2 were calculated by z-scores using HCs. Clusters that overlapped with the lesion labels were considered true positives (TPs); clusters with no overlap were considered false positives (FPs). Two-sample t-tests were performed to compare MRF measures between TP/FP clusters. A neural network model was trained using MRF values and cluster volume to distinguish TP/FP clusters. Ten-fold cross-validation was used to evaluate model performance at the cluster level. Leave-one-patient-out cross-validation was used to evaluate performance at the patient level. RESULTS MRF metrics were significantly higher in TP than FP clusters, including GM T1, normalized WM T1, and normalized WM T2. The neural network model with normalized MRF measures and cluster volume as input achieved mean area under the curve (AUC) of .83, sensitivity of 82.1%, and specificity of 71.7%. This model showed superior performance over direct thresholding of MAP18 FCD probability map at both the cluster and patient levels, eliminating ≥75% FP clusters in 30% of patients and ≥50% of FP clusters in 91% of patients. SIGNIFICANCE This pilot study suggests the efficacy of MRF for reducing FPs in FCD detection, due to its quantitative values reflecting in vivo pathological changes. © 2024 International League Against Epilepsy.
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Affiliation(s)
- Zheng Ding
- Epilepsy Center, Neurological Institute - Cleveland Clinic, Cleveland, Ohio
- Biomedical Engineering - Case Western Reserve University, Cleveland, Ohio
| | - Siyuan Hu
- Biomedical Engineering - Case Western Reserve University, Cleveland, Ohio
| | - Ting-Yu Su
- Epilepsy Center, Neurological Institute - Cleveland Clinic, Cleveland, Ohio
- Biomedical Engineering - Case Western Reserve University, Cleveland, Ohio
| | - Joon Yul Choi
- Epilepsy Center, Neurological Institute - Cleveland Clinic, Cleveland, Ohio
- Biomedical Engineering - Yonsei University, Wonju, Republic of Korea
| | - Spencer Morris
- Epilepsy Center, Neurological Institute - Cleveland Clinic, Cleveland, Ohio
- Biomedical Engineering - Case Western Reserve University, Cleveland, Ohio
| | - Xiaofeng Wang
- Quantitative Health Science - Cleveland Clinic, Cleveland, Ohio
| | - Ken Sakaie
- Imaging Institute - Cleveland Clinic, Cleveland, Ohio
| | - Hiroatsu Murakami
- Epilepsy Center, Neurological Institute - Cleveland Clinic, Cleveland, Ohio
| | | | - Ingmar Blümcke
- Epilepsy Center, Neurological Institute - Cleveland Clinic, Cleveland, Ohio
- Neuropathology - University Hospital Erlangen, Erlangen, Germany
| | - Stephen Jones
- Imaging Institute - Cleveland Clinic, Cleveland, Ohio
| | - Imad Najm
- Epilepsy Center, Neurological Institute - Cleveland Clinic, Cleveland, Ohio
| | - Dan Ma
- Biomedical Engineering - Case Western Reserve University, Cleveland, Ohio
| | - Zhong Irene Wang
- Epilepsy Center, Neurological Institute - Cleveland Clinic, Cleveland, Ohio
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Schachenhofer J, Gruber VE, Fehrer SV, Haider C, Glatter S, Liszewska E, Höftberger R, Aronica E, Rössler K, Jaworski J, Scholl T, Feucht M. Targeting the EGFR pathway: An alternative strategy for the treatment of tuberous sclerosis complex? Neuropathol Appl Neurobiol 2024; 50:e12974. [PMID: 38562027 DOI: 10.1111/nan.12974] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/07/2023] [Revised: 02/29/2024] [Accepted: 03/06/2024] [Indexed: 04/04/2024]
Abstract
INTRODUCTION Tuberous sclerosis complex (TSC) is caused by variants in TSC1/TSC2, leading to constitutive activation of the mammalian target of rapamycin (mTOR) complex 1. Therapy with everolimus has been approved for TSC, but variations in success are frequent. Recently, caudal late interneuron progenitor (CLIP) cells were identified as a common origin of the TSC brain pathologies such as subependymal giant cell astrocytomas (SEGA) and cortical tubers (CT). Further, targeting the epidermal growth factor receptor (EGFR) with afatinib, which is expressed in CLIP cells, reduces cell growth in cerebral TSC organoids. However, investigation of clinical patient-derived data is lacking. AIMS Observation of EGFR expression in SEGA, CT and focal cortical dysplasia (FCD) 2B human brain specimen and investigation of whether its inhibition could be a potential therapeutic intervention for these patients. METHODS Brain specimens of 23 SEGAs, 6 CTs, 20 FCD2Bs and 17 controls were analysed via immunohistochemistry to characterise EGFR expression, cell proliferation (via Mib1) and mTOR signalling. In a cell-based assay using primary patient-derived cells (CT n = 1, FCD2B n = 1 and SEGA n = 4), the effects of afatinib and everolimus on cell proliferation and cell viability were observed. RESULTS EGFR overexpression was observed in histological sections of SEGA, CT and FCD2B patients. Both everolimus and afatinib decreased the proliferation and viability in primary SEGA, tuber and FCD2B cells. CONCLUSION Our study demonstrates that EGFR suppression might be an effective alternative treatment option for SEGAs and tubers, as well as other mTOR-associated malformations of cortical development, including FCD2B.
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Affiliation(s)
- Julia Schachenhofer
- Department Pediatric and Adolescent Medicine, Medical University of Vienna, Vienna, Austria
| | | | | | - Carmen Haider
- Division of Neuropathology and Neurochemistry, Department of Neurology, Medical University of Vienna, Vienna, Austria
- Comprehensive Center for Clinical Neurosciences and Mental Health, Medical University of Vienna, Vienna, Austria
| | - Sarah Glatter
- Department Pediatric and Adolescent Medicine, Medical University of Vienna, Vienna, Austria
| | - Ewa Liszewska
- International Institute of Molecular and Cell Biology, Warsaw, Poland
| | - Romana Höftberger
- Division of Neuropathology and Neurochemistry, Department of Neurology, Medical University of Vienna, Vienna, Austria
- Comprehensive Center for Clinical Neurosciences and Mental Health, Medical University of Vienna, Vienna, Austria
| | - Eleonora Aronica
- Department of (Neuro)Pathology, Amsterdam UMC, University of Amsterdam, Amsterdam Neuroscience, Amsterdam, Netherlands
- Stichting Epilepsie Instellingen Nederland (SEIN), Heemstede, Netherlands
| | - Karl Rössler
- Department of Neurosurgery, Medical University of Vienna, Vienna, Austria
| | - Jacek Jaworski
- International Institute of Molecular and Cell Biology, Warsaw, Poland
| | - Theresa Scholl
- Department Pediatric and Adolescent Medicine, Medical University of Vienna, Vienna, Austria
| | - Martha Feucht
- Department Pediatric and Adolescent Medicine, Medical University of Vienna, Vienna, Austria
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François L, Romagnolo A, Luinenburg MJ, Anink JJ, Godard P, Rajman M, van Eyll J, Mühlebner A, Skelton A, Mills JD, Dedeurwaerdere S, Aronica E. Identification of gene regulatory networks affected across drug-resistant epilepsies. Nat Commun 2024; 15:2180. [PMID: 38467626 PMCID: PMC10928184 DOI: 10.1038/s41467-024-46592-2] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/01/2023] [Accepted: 03/01/2024] [Indexed: 03/13/2024] Open
Abstract
Epilepsy is a chronic and heterogenous disease characterized by recurrent unprovoked seizures, that are commonly resistant to antiseizure medications. This study applies a transcriptome network-based approach across epilepsies aiming to improve understanding of molecular disease pathobiology, recognize affected biological mechanisms and apply causal reasoning to identify therapeutic hypotheses. This study included the most common drug-resistant epilepsies (DREs), such as temporal lobe epilepsy with hippocampal sclerosis (TLE-HS), and mTOR pathway-related malformations of cortical development (mTORopathies). This systematic comparison characterized the global molecular signature of epilepsies, elucidating the key underlying mechanisms of disease pathology including neurotransmission and synaptic plasticity, brain extracellular matrix and energy metabolism. In addition, specific dysregulations in neuroinflammation and oligodendrocyte function were observed in TLE-HS and mTORopathies, respectively. The aforementioned mechanisms are proposed as molecular hallmarks of DRE with the identified upstream regulators offering opportunities for drug-target discovery and development.
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Affiliation(s)
- Liesbeth François
- UCB Pharma, Early Solutions, Braine-l'Alleud, Belgium.
- Department of (Neuro)Pathology, Amsterdam UMC, University of Amsterdam, Amsterdam Neuroscience, Amsterdam, The Netherlands.
| | - Alessia Romagnolo
- Department of (Neuro)Pathology, Amsterdam UMC, University of Amsterdam, Amsterdam Neuroscience, Amsterdam, The Netherlands
| | - Mark J Luinenburg
- Department of (Neuro)Pathology, Amsterdam UMC, University of Amsterdam, Amsterdam Neuroscience, Amsterdam, The Netherlands
| | - Jasper J Anink
- Department of (Neuro)Pathology, Amsterdam UMC, University of Amsterdam, Amsterdam Neuroscience, Amsterdam, The Netherlands
| | | | - Marek Rajman
- UCB Pharma, Early Solutions, Braine-l'Alleud, Belgium
| | | | - Angelika Mühlebner
- Department of (Neuro)Pathology, Amsterdam UMC, University of Amsterdam, Amsterdam Neuroscience, Amsterdam, The Netherlands
- Department of Pathology, University Medical Center Utrecht, Utrecht, The Netherlands
| | | | - James D Mills
- Department of (Neuro)Pathology, Amsterdam UMC, University of Amsterdam, Amsterdam Neuroscience, Amsterdam, The Netherlands
- Department of Clinical and Experimental Epilepsy, UCL Queen Square Institute of Neurology, London, UK
- Chalfont Centre for Epilepsy, Chalfont St Peter, Chalfont, UK
| | | | - Eleonora Aronica
- Department of (Neuro)Pathology, Amsterdam UMC, University of Amsterdam, Amsterdam Neuroscience, Amsterdam, The Netherlands.
- Stichting Epilepsie Instellingen Nederland (SEIN), Heemstede, The Netherlands.
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Li J, Qi H, Chen Y, Zhu X. Epilepsy and demyelination: Towards a bidirectional relationship. Prog Neurobiol 2024; 234:102588. [PMID: 38378072 DOI: 10.1016/j.pneurobio.2024.102588] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/14/2024] [Accepted: 02/13/2024] [Indexed: 02/22/2024]
Abstract
Demyelination stands out as a prominent feature in individuals with specific types of epilepsy. Concurrently, individuals with demyelinating diseases, such as multiple sclerosis (MS) are at a greater risk of developing epilepsy compared to non-MS individuals. These bidirectional connections raise the question of whether both pathological conditions share common pathogenic mechanisms. This review focuses on the reciprocal relationship between epilepsy and demyelination diseases. We commence with an overview of the neurological basis of epilepsy and demyelination diseases, followed by an exploration of how our comprehension of these two disorders has evolved in tandem. Additionally, we discuss the potential pathogenic mechanisms contributing to the interactive relationship between these two diseases. A more nuanced understanding of the interplay between epilepsy and demyelination diseases has the potential to unveiling the molecular intricacies of their pathological relationships, paving the way for innovative directions in future clinical management and treatment strategies for these diseases.
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Affiliation(s)
- Jiayi Li
- Department of Pharmacology, Medical School of Southeast University, Nanjing, China; Clinical Medicine, Medical School of Southeast University, Nanjing, China
| | - Honggang Qi
- Department of Pharmacology, Medical School of Southeast University, Nanjing, China
| | - Yuzhou Chen
- Department of Pharmacology, Medical School of Southeast University, Nanjing, China; Clinical Medicine, Medical School of Southeast University, Nanjing, China
| | - Xinjian Zhu
- Department of Pharmacology, Medical School of Southeast University, Nanjing, China.
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Cha J, Filatov G, Smith SJ, Gammaitoni AR, Lothe A, Reeder T. Fenfluramine increases survival and reduces markers of neurodegeneration in a mouse model of Dravet syndrome. Epilepsia Open 2024; 9:300-313. [PMID: 38018342 PMCID: PMC10839300 DOI: 10.1002/epi4.12873] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/03/2023] [Accepted: 11/21/2023] [Indexed: 11/30/2023] Open
Abstract
OBJECTIVE In patients with Dravet syndrome (DS), fenfluramine reduced convulsive seizure frequency and provided clinical benefit in nonseizure endpoints (e.g., executive function, survival). In zebrafish mutant scn1 DS models, chronic fenfluramine treatment preserved neuronal cytoarchitecture prior to seizure onset and prevented gliosis; here, we extend these findings to a mammalian model of DS (Scn1a+/- mice) by evaluating the effects of fenfluramine on neuroinflammation (degenerated myelin, activated microglia) and survival. METHODS Scn1a+/- DS mice were treated subcutaneously once daily with fenfluramine (15 mg/kg) or vehicle from postnatal day (PND) 7 until 35-37. Sagittal brain sections were processed for immunohistochemistry using antibodies to degraded myelin basic protein (D-MBP) for degenerated myelin, or CD11b for activated (inflammatory) microglia; sections were scored semi-quantitatively. Apoptotic nuclei were quantified by TUNEL assay. Statistical significance was evaluated by 1-way ANOVA with post-hoc Dunnett's test (D-MBP, CD11b, and TUNEL) or Logrank Mantel-Cox (survival). RESULTS Quantitation of D-MBP immunostaining per 0.1 mm2 unit area of the parietal cortex and hippocampus CA3 yielded significantly higher spheroidal and punctate myelin debris counts in vehicle-treated DS mice than in wild-type mice. Fenfluramine treatment in DS mice significantly reduced these counts. Activated CD11b + microglia were more abundant in DS mouse corpus callosum and hippocampus than in wild-type controls. Fenfluramine treatment of DS mice resulted in significantly fewer activated CD11b + microglia than vehicle-treated DS mice in these brain regions. TUNEL staining in corpus callosum was increased in DS mice relative to wild-type controls. Fenfluramine treatment in DS mice lowered TUNEL staining relative to vehicle-treated DS mice. By PND 35-37, 55% of control DS mice had died, compared with 24% of DS mice receiving fenfluramine treatment (P = 0.0291). SIGNIFICANCE This is the first report of anti-neuroinflammation and pro-survival after fenfluramine treatment in a mammalian DS model. These results corroborate prior data in humans and animal models and suggest important pharmacological activities for fenfluramine beyond seizure reduction. PLAIN LANGUAGE SUMMARY Dravet syndrome is a severe epilepsy disorder that impairs learning and causes premature death. Clinical studies in patients with Dravet syndrome show that fenfluramine reduces convulsive seizures. Additional studies suggest that fenfluramine may have benefits beyond seizures, including promoting survival and improving control over emotions and behavior. Our study is the first to use a Dravet mouse model to investigate nonseizure outcomes of fenfluramine. Results showed that fenfluramine treatment of Dravet mice reduced neuroinflammation significantly more than saline treatment. Fenfluramine-treated Dravet mice also lived longer than saline-treated mice. These results support clinical observations that fenfluramine may have benefits beyond seizures.
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Affiliation(s)
- John Cha
- University of California San FranciscoSan FranciscoCaliforniaUSA
- Zogenix, Inc. (now a part of UCB)EmeryvilleCaliforniaUSA
| | - Gregory Filatov
- Zogenix, Inc. (now a part of UCB)EmeryvilleCaliforniaUSA
- Crosshair Therapeutics, Inc.SunnyvaleCaliforniaUSA
| | - Steven J. Smith
- Zogenix, Inc. (now a part of UCB)EmeryvilleCaliforniaUSA
- WuXi AppTec, Inc.San FranciscoCaliforniaUSA
| | | | | | - Thadd Reeder
- Zogenix, Inc. (now a part of UCB)EmeryvilleCaliforniaUSA
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Pokošová P, Kala D, Šanda J, Ježdík P, Prysiazhniuk Y, Faridová A, Jahodová A, Bělohlávková A, Kalina A, Holubová Z, Jurášek B, Kynčl M, Otáhal J. Magnetic resonance imaging techniques for indirect assessment of myelin content in the brain using standard T1w and T2w MRI sequences and postprocessing analysis. Physiol Res 2023; 72:S573-S585. [PMID: 38165761 PMCID: PMC10861246 DOI: 10.33549/physiolres.935250] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/31/2023] [Accepted: 10/10/2023] [Indexed: 02/01/2024] Open
Abstract
Magnetic Resonance Imaging (MRI) has revolutionized our ability to non-invasively study the brain's structural and functional properties. However, detecting myelin, a crucial component of white matter, remains challenging due to its indirect visibility on conventional MRI scans. Myelin plays a vital role in neural signal transmission and is associated with various neurological conditions. Understanding myelin distribution and content is crucial for insights into brain development, aging, and neurological disorders. Although specialized MRI sequences can estimate myelin content, these are time-consuming. Also, many patients sent to specialized neurological centers have an MRI of the brain already scanned. In this study, we focused on techniques utilizing standard MRI T1-weighted (T1w) and T2 weighted (T2w) sequences commonly used in brain imaging protocols. We evaluated the applicability of the T1w/T2w ratio in assessing myelin content by comparing it to quantitative T1 mapping (qT1). Our study included 1 healthy adult control and 7 neurologic patients (comprising both pediatric and adult populations) with epilepsy originating from focal epileptogenic lesions visible on MRI structural scans. Following image acquisition on a 3T Siemens Vida scanner, datasets were co registered, and segmented into anatomical regions using the Fastsurfer toolbox, and T1w/T2w ratio maps were calculated in Matlab software. We further assessed interhemispheric differences in volumes of individual structures, their signal intensity, and the correlation of the T1w/T2w ratio to qT1. Our data demonstrate that in situations where a dedicated myelin-sensing sequence such as qT1 is not available, the T1w/T2w ratio provides significantly better information than T1w alone. By providing indirect information about myelin content, this technique offers a valuable tool for understanding the neurobiology of myelin-related conditions using basic brain scans.
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Affiliation(s)
- P Pokošová
- Department of Pathophysiology, Second Faculty of Medicine, Charles University, Praha 5, Czech Republic.
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Bahabry R, Hauser RM, Sánchez RG, Jago SS, Ianov L, Stuckey RJ, Parrish RR, Hoef LV, Lubin FD. Alterations in DNA 5-hydroxymethylation Patterns in the Hippocampus of an Experimental Model of Refractory Epilepsy. BIORXIV : THE PREPRINT SERVER FOR BIOLOGY 2023:2023.10.03.560698. [PMID: 37873276 PMCID: PMC10592907 DOI: 10.1101/2023.10.03.560698] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 10/25/2023]
Abstract
Temporal lobe epilepsy (TLE) is a type of focal epilepsy characterized by spontaneous recurrent seizures originating from the hippocampus. The epigenetic reprogramming hypothesis of epileptogenesis suggests that the development of TLE is associated with alterations in gene transcription changes resulting in a hyperexcitable network in TLE. DNA 5-methylcytosine (5-mC) is an epigenetic mechanism that has been associated with chronic epilepsy. However, the contribution of 5-hydroxymethylcytosine (5-hmC), a product of 5-mC demethylation by the Ten-Eleven Translocation (TET) family proteins in chronic TLE is poorly understood. 5-hmC is abundant in the brain and acts as a stable epigenetic mark altering gene expression through several mechanisms. Here, we found that the levels of bulk DNA 5-hmC but not 5-mC were significantly reduced in the hippocampus of human TLE patients and in the kainic acid (KA) TLE rat model. Using 5-hmC hMeDIP-sequencing, we characterized 5-hmC distribution across the genome and found bidirectional regulation of 5-hmC at intergenic regions within gene bodies. We found that hypohydroxymethylated 5-hmC intergenic regions were associated with several epilepsy-related genes, including Gal , SV2, and Kcnj11 and hyperdroxymethylation 5-hmC intergenic regions were associated with Gad65 , TLR4 , and Bdnf gene expression. Mechanistically, Tet1 knockdown in the hippocampus was sufficient to decrease 5-hmC levels and increase seizure susceptibility following KA administration. In contrast, Tet1 overexpression in the hippocampus resulted in increased 5-hmC levels associated with improved seizure resiliency in response to KA. These findings suggest an important role for 5-hmC as an epigenetic regulator of epilepsy that can be manipulated to influence seizure outcomes.
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10
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Wang Y, Yu T, Blümcke I, Cai Y, Sun K, Gao R, Wang Y, Fu Y, Wang W, Wang Y, Zhang G, Piao Y. The clinico-pathological characterisation of focal cortical dysplasia type IIb genetically defined by MTOR mosaicism. Neuropathol Appl Neurobiol 2023; 49:e12874. [PMID: 36544434 DOI: 10.1111/nan.12874] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/19/2021] [Revised: 08/18/2022] [Accepted: 10/11/2022] [Indexed: 12/24/2022]
Abstract
AIMS Focal cortical dysplasia (FCD) is a major cause of drug-resistant paediatric epilepsy and is amenable to successful neurosurgical resection. FCD ILAE Type IIb is the most common FCD subtype, and brain somatic mutations affecting the mTOR pathway play a major pathogenic role. The aim of this study was to comprehensively describe the genotype-phenotype association of 20 patients with histopathologically confirmed FCDIIb using next generation sequencing (NGS) of paired blood-brain samples. METHODS Clinical and neuropathological data were retrospectively reviewed from the hospital archive. The NGS panel included 11 mTOR-pathway-related genes with maximum coverage of 2000×. The detected variants were validated by digital droplet PCR. RESULTS Pathogenic MTOR variants were identified in 10 patients (50%). Further comparison with MTOR-wildtype FCDIIb suggested a profound genotype-phenotype association characterised by (1) a non-temporal lobe lesion on MRI, (2) a larger lesion volume occupying grey and white matter (3.032 ± 1.859 cm3 vs 1.110 ± 0.856 cm3 , p = 0.014), (3) more balloon cells (50.20 ± 14.40 BC/mm2 vs 31.64 ± 30.56 BC/mm2 , p = 0.099) and dysmorphic neurons (48.72 ± 19.47DN/mm2 vs 15.28 ± 13.95DN/mm2 , p = 0.000) and (4) a positive correlation between VAF and the lesion volume (r = 0.802, p = 0.017). CONCLUSIONS Our study identified frequent MTOR mutations in the cell-rich FCDIIb phenotype, clinically characterised by a non-temporal location and large lesion volume. Comprehensive genotype-phenotype associations will help us further explore and define the broad spectrum of FCD lesions to make more targeted therapies available in the realm of epileptology.
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Affiliation(s)
- Yajie Wang
- Department of Pathology, Xuanwu Hospital, Capital Medical University, Beijing, China.,Clinical Research Center for Epilepsy, Capital Medical University, Beijing, China.,National Center for Neurological Disorders, Beijing, China
| | - Tao Yu
- Clinical Research Center for Epilepsy, Capital Medical University, Beijing, China.,National Center for Neurological Disorders, Beijing, China.,Beijing Institute of Functional Neurosurgery, Xuanwu Hospital, Capital Medical University, Beijing, China.,Department of Functional Neurosurgery, Xuanwu Hospital, Capital Medical University, Beijing, China
| | - Ingmar Blümcke
- Department of Neuropathology, University Hospital Erlangen, Erlangen, Germany
| | - Yanning Cai
- Clinical Research Center for Epilepsy, Capital Medical University, Beijing, China.,National Center for Neurological Disorders, Beijing, China.,Department of Neurobiology and Clinical Biobank, Xuanwu Hospital, Capital Medical University, Beijing, China
| | - Ke Sun
- Clinical Research Center for Epilepsy, Capital Medical University, Beijing, China.,National Center for Neurological Disorders, Beijing, China.,Beijing Institute of Functional Neurosurgery, Xuanwu Hospital, Capital Medical University, Beijing, China.,Department of Functional Neurosurgery, Xuanwu Hospital, Capital Medical University, Beijing, China
| | - Runshi Gao
- Clinical Research Center for Epilepsy, Capital Medical University, Beijing, China.,National Center for Neurological Disorders, Beijing, China.,Beijing Institute of Functional Neurosurgery, Xuanwu Hospital, Capital Medical University, Beijing, China.,Department of Functional Neurosurgery, Xuanwu Hospital, Capital Medical University, Beijing, China
| | - Yujiao Wang
- Department of Pathology, Xuanwu Hospital, Capital Medical University, Beijing, China.,Clinical Research Center for Epilepsy, Capital Medical University, Beijing, China.,National Center for Neurological Disorders, Beijing, China
| | - Yongjuan Fu
- Department of Pathology, Xuanwu Hospital, Capital Medical University, Beijing, China.,Clinical Research Center for Epilepsy, Capital Medical University, Beijing, China.,National Center for Neurological Disorders, Beijing, China
| | - Wei Wang
- Clinical Research Center for Epilepsy, Capital Medical University, Beijing, China.,National Center for Neurological Disorders, Beijing, China.,Department of Neurology, Xuanwu Hospital, Capital Medical University, Beijing, China
| | - Yuping Wang
- Clinical Research Center for Epilepsy, Capital Medical University, Beijing, China.,National Center for Neurological Disorders, Beijing, China.,Department of Neurology, Xuanwu Hospital, Capital Medical University, Beijing, China.,Beijing Key Laboratory of Neuromodulation, Beijing, China.,Center of Epilepsy, Institute of Sleep and Consciousness Disorders, Beijing Institute for Brain Disorders, Capital Medical University, Beijing, China
| | - Guojun Zhang
- Clinical Research Center for Epilepsy, Capital Medical University, Beijing, China.,National Center for Neurological Disorders, Beijing, China.,Beijing Institute of Functional Neurosurgery, Xuanwu Hospital, Capital Medical University, Beijing, China.,Department of Functional Neurosurgery, Xuanwu Hospital, Capital Medical University, Beijing, China
| | - Yueshan Piao
- Department of Pathology, Xuanwu Hospital, Capital Medical University, Beijing, China.,Clinical Research Center for Epilepsy, Capital Medical University, Beijing, China.,National Center for Neurological Disorders, Beijing, China
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11
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Developing Novel Experimental Models of m-TORopathic Epilepsy and Related Neuropathologies: Translational Insights from Zebrafish. Int J Mol Sci 2023; 24:ijms24021530. [PMID: 36675042 PMCID: PMC9866103 DOI: 10.3390/ijms24021530] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/09/2022] [Revised: 12/28/2022] [Accepted: 12/29/2022] [Indexed: 01/15/2023] Open
Abstract
The mammalian target of rapamycin (mTOR) is an important molecular regulator of cell growth and proliferation. Brain mTOR activity plays a crucial role in synaptic plasticity, cell development, migration and proliferation, as well as memory storage, protein synthesis, autophagy, ion channel expression and axonal regeneration. Aberrant mTOR signaling causes a diverse group of neurological disorders, termed 'mTORopathies'. Typically arising from mutations within the mTOR signaling pathway, these disorders are characterized by cortical malformations and other neuromorphological abnormalities that usually co-occur with severe, often treatment-resistant, epilepsy. Here, we discuss recent advances and current challenges in developing experimental models of mTOR-dependent epilepsy and other related mTORopathies, including using zebrafish models for studying these disorders, as well as outline future directions of research in this field.
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12
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Shimada T, Yamagata K. Spine morphogenesis and synapse formation in tubular sclerosis complex models. Front Mol Neurosci 2022; 15:1019343. [PMID: 36606143 PMCID: PMC9807618 DOI: 10.3389/fnmol.2022.1019343] [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: 08/15/2022] [Accepted: 12/05/2022] [Indexed: 12/24/2022] Open
Abstract
Tuberous sclerosis complex (TSC) is caused by mutations in the Tsc1 or Tsc2 genes, whose products form a complex and inactivate the small G-protein Rheb1. The activation of Rheb1 may cause refractory epilepsy, intellectual disability, and autism, which are the major neuropsychiatric manifestations of TSC. Abnormalities in dendritic spines and altered synaptic structure are hallmarks of epilepsy, intellectual disability, and autism. In addition, spine dysmorphology and aberrant synapse formation are observed in TSC animal models. Therefore, it is important to investigate the molecular mechanism underlying the regulation of spine morphology and synapse formation in neurons to identify therapeutic targets for TSC. In this review, we focus on the representative proteins regulated by Rheb1 activity, mTORC1 and syntenin, which are pivotal downstream factors of Rheb1 in the alteration of spine formation and synapse function in TSC neurons.
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Affiliation(s)
- Tadayuki Shimada
- Child Brain Project, Tokyo Metropolitan Institute of Medical Science, Tokyo, Japan,*Correspondence: Tadayuki Shimada,
| | - Kanato Yamagata
- Child Brain Project, Tokyo Metropolitan Institute of Medical Science, Tokyo, Japan,Department of Psychiatry, Takada Nishishiro Hospital, Niigata, Japan,Kanato Yamagata,
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13
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Advances in the genetics and neuropathology of tuberous sclerosis complex: edging closer to targeted therapy. Lancet Neurol 2022; 21:843-856. [DOI: 10.1016/s1474-4422(22)00213-7] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/16/2021] [Revised: 03/09/2022] [Accepted: 05/11/2022] [Indexed: 12/23/2022]
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14
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Genetic pathogenesis of the epileptogenic lesions in Tuberous Sclerosis Complex: Therapeutic targeting of the mTOR pathway. Epilepsy Behav 2022; 131:107713. [PMID: 33431351 DOI: 10.1016/j.yebeh.2020.107713] [Citation(s) in RCA: 6] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 07/07/2020] [Revised: 12/14/2020] [Accepted: 12/14/2020] [Indexed: 12/13/2022]
Abstract
Tuberous sclerosis complex (TSC) is a genetic multisystem disease due to the mutation in one of the two genes TSC1 and TSC2, affecting several organs and systems and carrying a significant risk of early onset and refractory seizures. The pathogenesis of this complex disorder is now well known, with most of TSC-related manifestations being a consequence of the overactivation of the mammalian Target of Rapamycin (mTOR) complex. The discovery of this underlying mechanism paved the way for the use of a class of drugs called mTOR inhibitors including rapamycin and everolimus and specifically targeting this pathway. Rapamycin has been widely used in different animal models of TSC-related epilepsy and proved to be able not only to suppress seizures but also to prevent the development of epilepsy, thus demonstrating an antiepileptogenic potential. In some models, it also showed some benefit on neuropsychiatric manifestations associated with TSC. Everolimus has recently been approved by the US Food and Drug Administration and the European Medical Agency for the treatment of refractory seizures associated with TSC starting from the age of 2 years. It demonstrated a clear benefit when compared to placebo on reducing the frequency of different seizure types and exerting a higher effect in younger children. In conclusion, mTOR cascade can be a potentially major cause of TSC-associated epilepsy and neurodevelopmental disability, and additional research should investigate if early suppression of abnormal mTOR signal with mTOR inhibitors before seizure onset can be a more efficient approach and an effective antiepileptogenic and disease-modifying strategy in infants with TSC.
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15
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Gruber VE, Luinenburg MJ, Colleselli K, Endmayr V, Anink JJ, Zimmer TS, Jansen F, Gosselaar P, Coras R, Scholl T, Blumcke I, Pimentel J, Hainfellner JA, Höftberger R, Rössler K, Feucht M, van Scheppingen J, Aronica E, Mühlebner A. Increased expression of complement components in tuberous sclerosis complex and focal cortical dysplasia type 2B brain lesions. Epilepsia 2021; 63:364-374. [PMID: 34904712 PMCID: PMC9299842 DOI: 10.1111/epi.17139] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/21/2021] [Revised: 11/15/2021] [Accepted: 11/16/2021] [Indexed: 01/07/2023]
Abstract
Objective Increasing evidence supports the contribution of inflammatory mechanisms to the neurological manifestations of epileptogenic developmental pathologies linked to mammalian target of rapamycin (mTOR) pathway dysregulation (mTORopathies), such as tuberous sclerosis complex (TSC) and focal cortical dysplasia (FCD). In this study, we aimed to investigate the expression pattern and cellular distribution of the complement factors C1q and C3 in resected cortical tissue of clinically well‐characterized patients with TSC and FCD2B. Methods We applied immunohistochemistry in TSC (n = 29) and FCD2B (n = 32) samples and compared them to autopsy and biopsy controls (n = 27). Furthermore, protein expression was observed via Western blot, and for descriptive colocalization studies immunofluorescence double labeling was performed. Results Protein expression for C3 was significantly upregulated in TSC and FCD2B white and gray matter lesions compared to controls. Staining of the synaptic vesicle protein synaptophysin showed a remarkable increase in the white matter of both TSC and FCD2B. Furthermore, confocal imaging revealed colocalization of complement factors with astroglial, microglial, neuronal, and abnormal cells in various patterns. Significance Our results demonstrate that the prominent activation of the complement pathway represents a common pathological hallmark of TSC and FCD2B, suggesting that complement overactivation may play a role in these mTORopathies.
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Affiliation(s)
| | - Mark J Luinenburg
- Department of (Neuro)Pathology, Amsterdam University Medical Center, University of Amsterdam, Amsterdam, the Netherlands
| | - Katrin Colleselli
- Department of Pediatrics and Adolescent Medicine, Medical University of Vienna, Vienna, Austria
| | - Verena Endmayr
- Division of Neuropathology and Neurochemistry, Department of Neurology, Medical University of Vienna, Vienna, Austria
| | - Jasper J Anink
- Department of (Neuro)Pathology, Amsterdam University Medical Center, University of Amsterdam, Amsterdam, the Netherlands
| | - Till S Zimmer
- Department of (Neuro)Pathology, Amsterdam University Medical Center, University of Amsterdam, Amsterdam, the Netherlands
| | - Floor Jansen
- Department of Child Neurology, Brain Center, University Medical Center Utrecht, Member of the European Reference Network EpiCARE, Utrecht, the Netherlands
| | - Peter Gosselaar
- Department of Neurosurgery, University Medical Center Utrecht, Utrecht, the Netherlands
| | - Roland Coras
- Department of Neuropathology, University Hospital Erlangen, Erlangen, Germany
| | - Theresa Scholl
- Department of Pediatrics and Adolescent Medicine, Medical University of Vienna, Vienna, Austria
| | - Ingmar Blumcke
- Department of Neuropathology, University Hospital Erlangen, Erlangen, Germany
| | - José Pimentel
- Department of Neurology, Santa Maria Hospital, Lisbon, Portugal
| | - Johannes A Hainfellner
- Division of Neuropathology and Neurochemistry, Department of Neurology, Medical University of Vienna, Vienna, Austria
| | - Romana Höftberger
- Division of Neuropathology and Neurochemistry, Department of Neurology, Medical University of Vienna, Vienna, Austria
| | - Karl Rössler
- Department of Neurosurgery, Medical University of Vienna, Vienna, Austria
| | - Martha Feucht
- Department of Pediatrics and Adolescent Medicine, Medical University of Vienna, Vienna, Austria
| | - Jackelien van Scheppingen
- Department of (Neuro)Pathology, Amsterdam University Medical Center, University of Amsterdam, Amsterdam, the Netherlands
| | - Eleonora Aronica
- Department of (Neuro)Pathology, Amsterdam University Medical Center, University of Amsterdam, Amsterdam, the Netherlands.,Epilepsy Institutes of the Netherlands Foundation, Heemstede, the Netherlands
| | - Angelika Mühlebner
- Department of (Neuro)Pathology, Amsterdam University Medical Center, University of Amsterdam, Amsterdam, the Netherlands.,Department of Pathology, University Medical Center Utrecht, Utrecht, the Netherlands
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16
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Gruber V, Lang J, Endmayr V, Diehm R, Pimpel B, Glatter S, Anink JJ, Bongaarts A, Luinenburg MJ, Reinten RJ, van der Wel N, Larsen P, Hainfellner JA, Rössler K, Aronica E, Scholl T, Mühlebner A, Feucht M. Impaired myelin production due to an intrinsic failure of oligodendrocytes in mTORpathies. Neuropathol Appl Neurobiol 2021; 47:812-825. [PMID: 34173252 PMCID: PMC8518586 DOI: 10.1111/nan.12744] [Citation(s) in RCA: 12] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/21/2021] [Accepted: 05/24/2021] [Indexed: 12/22/2022]
Abstract
AIMS We aim to evaluate if the myelin pathology observed in epilepsy-associated focal cortical dysplasia type 2B (FCD2B) and-histologically indistinguishable-cortical tubers of tuberous sclerosis complex (TSC) is primarily related to the underlying malformation or constitutes a secondary phenomenon due to the toxic microenvironment created by epileptic seizures. We also aim to investigate the possible beneficial effect of the mTOR pathway regulator everolimus on white matter pathology. METHODS Primary mixed glial cell cultures derived from epilepsy surgery specimens of one TSC and seven FCD2B patients were grown on polycaprolactone fibre matrices and analysed using immunofluorescence and electron microscopy. Unaffected white matter from three age-matched epilepsy patients with mild malformations of cortical development (mMCD) and one with FCD3D served as controls. Additionally, TSC2 knock-out was performed using an oligodendroglial cell line. Myelination capacities of nanofibre grown cells in an inflammatory environment after mTOR-inhibitor treatment with everolimus were further investigated. RESULTS Reduced oligodendroglial turnover, directly related to a lower myelin content was found in the patients' primary cells. In our culture model of myelination dynamics, primary cells grown under 'inflammatory condition' showed decreased myelination, that was repaired by treatment with everolimus. CONCLUSIONS Results obtained in patient-derived primary oligodendroglial and TSC2 knock-out cells suggest that maturation of oligodendroglia and production of a proper myelin sheath seem to be impaired as a result of mTOR pathway disturbance. Hence, oligodendroglial pathology may reflect a more direct effect of the abnormal genetic programme rather than to be an inactive bystander of chronic epilepsy.
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Affiliation(s)
- Victoria‐Elisabeth Gruber
- Department of Pediatrics and Adolescent MedicineMedical University of Vienna – Affiliated Partner of the ERN EpiCAREViennaAustria
| | - Judith Lang
- Department of Pediatrics and Adolescent MedicineMedical University of Vienna – Affiliated Partner of the ERN EpiCAREViennaAustria
| | - Verena Endmayr
- Division of Neuropathology and Neurochemistry, Department of NeurologyMedical University of ViennaViennaAustria
| | - Robert Diehm
- Department of Pediatrics and Adolescent MedicineMedical University of Vienna – Affiliated Partner of the ERN EpiCAREViennaAustria
| | - Birgit Pimpel
- Department of Pediatrics and Adolescent MedicineMedical University of Vienna – Affiliated Partner of the ERN EpiCAREViennaAustria
| | - Sarah Glatter
- Department of Pediatrics and Adolescent MedicineMedical University of Vienna – Affiliated Partner of the ERN EpiCAREViennaAustria
| | - Jasper J. Anink
- Department of (Neuro)Pathology, Amsterdam UMCUniversity of AmsterdamAmsterdamThe Netherlands
| | - Anika Bongaarts
- Department of (Neuro)Pathology, Amsterdam UMCUniversity of AmsterdamAmsterdamThe Netherlands
| | - Mark J. Luinenburg
- Department of (Neuro)Pathology, Amsterdam UMCUniversity of AmsterdamAmsterdamThe Netherlands
| | - Roy J. Reinten
- Department of (Neuro)Pathology, Amsterdam UMCUniversity of AmsterdamAmsterdamThe Netherlands
| | - Nicole van der Wel
- Department of (Neuro)Pathology, Amsterdam UMCUniversity of AmsterdamAmsterdamThe Netherlands
| | - Per Larsen
- Department of (Neuro)Pathology, Amsterdam UMCUniversity of AmsterdamAmsterdamThe Netherlands
| | - Johannes A. Hainfellner
- Division of Neuropathology and Neurochemistry, Department of NeurologyMedical University of ViennaViennaAustria
| | - Karl Rössler
- Department of NeurosurgeryMedical University of ViennaViennaAustria
| | - Eleonora Aronica
- Department of (Neuro)Pathology, Amsterdam UMCUniversity of AmsterdamAmsterdamThe Netherlands
- Stichting Epilepsie Instellingen Nederland (SEIN)HeemstedeThe Netherlands
| | - Theresa Scholl
- Department of Pediatrics and Adolescent MedicineMedical University of Vienna – Affiliated Partner of the ERN EpiCAREViennaAustria
| | - Angelika Mühlebner
- Department of PathologyUniversity Medical Center UtrechtUtrechtThe Netherlands
| | - Martha Feucht
- Department of Pediatrics and Adolescent MedicineMedical University of Vienna – Affiliated Partner of the ERN EpiCAREViennaAustria
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17
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Peixoto-Santos JE, Blumcke I. Neuropathology of the 21st century for the Latin American epilepsy community. Seizure 2021; 90:51-59. [DOI: 10.1016/j.seizure.2021.02.003] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/02/2020] [Revised: 01/18/2021] [Accepted: 02/01/2021] [Indexed: 12/13/2022] Open
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18
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Leite JP, Peixoto-Santos JE. Glia and extracellular matrix molecules: What are their importance for the electrographic and MRI changes in the epileptogenic zone? Epilepsy Behav 2021; 121:106542. [PMID: 31884121 DOI: 10.1016/j.yebeh.2019.106542] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 06/18/2019] [Revised: 09/02/2019] [Accepted: 09/04/2019] [Indexed: 12/22/2022]
Abstract
Glial cells and extracellular matrix (ECM) molecules are crucial for the maintenance of brain homeostasis. Especially because of their actions regarding neurotransmitter and ionic control, and synaptic function, these cells can potentially contribute to the hyperexcitability seen in the epileptogenic, while ECM changes are linked to synaptic reorganization. The present review will explore glial and ECM homeostatic roles and their potential contribution to tissue plasticity. Finally, we will address how glial, and ECM changes in the epileptogenic zone can be seen in magnetic resonance imaging (MRI), pointing out their importance as markers for the extension of the epileptogenic area. This article is part of the Special Issue "NEWroscience 2018".
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Affiliation(s)
- Joao Pereira Leite
- Neurosciences and Behavioral Sciences, Ribeirao Preto Medical School, University of Sao Paulo, Ribeirao Preto, Brazil.
| | - Jose Eduardo Peixoto-Santos
- Neurosciences and Behavioral Sciences, Ribeirao Preto Medical School, University of Sao Paulo, Ribeirao Preto, Brazil; Department of Neurology and Neurosurgery, Paulista School of Medicine, UNIFESP, Sao Paulo, Brazil
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19
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Srivastava A, Kumar K, Banerjee J, Tripathi M, Dubey V, Sharma D, Yadav N, Sharma MC, Lalwani S, Doddamani R, Chandra PS, Dixit AB. Transcriptomic profiling of high- and low-spiking regions reveals novel epileptogenic mechanisms in focal cortical dysplasia type II patients. Mol Brain 2021; 14:120. [PMID: 34301297 PMCID: PMC8305866 DOI: 10.1186/s13041-021-00832-4] [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: 03/21/2021] [Accepted: 07/14/2021] [Indexed: 11/15/2022] Open
Abstract
Focal cortical dysplasia (FCD) is a malformation of the cerebral cortex with poorly-defined epileptogenic zones (EZs), and poor surgical outcome in FCD is associated with inaccurate localization of the EZ. Hence, identifying novel epileptogenic markers to aid in the localization of EZ in patients with FCD is very much needed. High-throughput gene expression studies of FCD samples have the potential to uncover molecular changes underlying the epileptogenic process and identify novel markers for delineating the EZ. For this purpose, we, for the first time performed RNA sequencing of surgically resected paired tissue samples obtained from electrocorticographically graded high (MAX) and low spiking (MIN) regions of FCD type II patients and autopsy controls. We identified significant changes in the MAX samples of the FCD type II patients when compared to non-epileptic controls, but not in the case of MIN samples. We found significant enrichment for myelination, oligodendrocyte development and differentiation, neuronal and axon ensheathment, phospholipid metabolism, cell adhesion and cytoskeleton, semaphorins, and ion channels in the MAX region. Through the integration of both MAX vs non-epileptic control and MAX vs MIN RNA sequencing (RNA Seq) data, PLP1, PLLP, UGT8, KLK6, SOX10, MOG, MAG, MOBP, ANLN, ERMN, SPP1, CLDN11, TNC, GPR37, SLC12A2, ABCA2, ABCA8, ASPA, P2RX7, CERS2, MAP4K4, TF, CTGF, Semaphorins, Opalin, FGFs, CALB2, and TNC were identified as potential key regulators of multiple pathways related to FCD type II pathology. We have identified novel epileptogenic marker elements that may contribute to epileptogenicity in patients with FCD and could be possible markers for the localization of EZ.
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Affiliation(s)
| | - Krishan Kumar
- Dr B R Ambedkar Centre for Biomedical Research, University of Delhi, Delhi, 110007, India
| | | | | | - Vivek Dubey
- Department of Biophysics, AIIMS, New Delhi, India
| | - Devina Sharma
- Department of Neurosurgery, AIIMS, New Delhi, 110029, India
| | - Nitin Yadav
- Dr B R Ambedkar Centre for Biomedical Research, University of Delhi, Delhi, 110007, India
| | - M C Sharma
- Department of Pathology, AIIMS, New Delhi, India
| | - Sanjeev Lalwani
- Department of Forensic Medicine and Toxicology, AIIMS, New Delhi, India
| | | | - P Sarat Chandra
- Department of Neurosurgery, AIIMS, New Delhi, 110029, India.
| | - Aparna Banerjee Dixit
- Dr B R Ambedkar Centre for Biomedical Research, University of Delhi, Delhi, 110007, India.
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20
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Zimmer TS, Broekaart DWM, Luinenburg M, Mijnsbergen C, Anink JJ, Sim NS, Michailidou I, Jansen FE, van Rijen PC, Lee JH, François L, van Eyll J, Dedeurwaerdere S, van Vliet EA, Mühlebner A, Mills JD, Aronica E. Balloon cells promote immune system activation in focal cortical dysplasia type 2b. Neuropathol Appl Neurobiol 2021; 47:826-839. [PMID: 34003514 PMCID: PMC8518746 DOI: 10.1111/nan.12736] [Citation(s) in RCA: 14] [Impact Index Per Article: 4.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/13/2020] [Accepted: 05/12/2021] [Indexed: 11/29/2022]
Abstract
Aims Focal cortical dysplasia (FCD) type 2 is an epileptogenic malformation of the neocortex associated with somatic mutations in the mammalian target of rapamycin (mTOR) pathway. Histopathologically, FCD 2 is subdivided into FCD 2a and FCD 2b, the only discriminator being the presence of balloon cells (BCs) in FCD 2b. While pro‐epileptogenic immune system activation and inflammatory responses are commonly detected in both subtypes, it is unknown what contextual role BCs play. Methods The present study employed RNA sequencing of surgically resected brain tissue from FCD 2a (n = 11) and FCD 2b (n = 20) patients compared to autopsy control (n = 9) focusing on three immune system processes: adaptive immunity, innate immunity and cytokine production. This analysis was followed by immunohistochemistry on a clinically well‐characterised FCD 2 cohort. Results Differential expression analysis revealed stronger expression of components of innate immunity, adaptive immunity and cytokine production in FCD 2b than in FCD 2a, particularly complement activation and antigen presentation. Immunohistochemical analysis confirmed these findings, with strong expression of leukocyte antigen I and II in FCD 2b as compared to FCD 2a. Moreover, T‐lymphocyte tissue infiltration was elevated in FCD 2b. Expression of markers of immune system activation in FCD 2b was concentrated in subcortical white matter. Lastly, antigen presentation was strongly correlated with BC load in FCD 2b lesions. Conclusion We conclude that, next to mutation‐driven mTOR activation and seizure activity, BCs are crucial drivers of inflammation in FCD 2b. Our findings indicate that therapies targeting inflammation may be beneficial in FCD 2b.
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Affiliation(s)
- Till S Zimmer
- Department of (Neuro)Pathology, Amsterdam UMC, University of Amsterdam, Amsterdam Neuroscience, Amsterdam, The Netherlands
| | - Diede W M Broekaart
- Department of (Neuro)Pathology, Amsterdam UMC, University of Amsterdam, Amsterdam Neuroscience, Amsterdam, The Netherlands
| | - Mark Luinenburg
- Department of (Neuro)Pathology, Amsterdam UMC, University of Amsterdam, Amsterdam Neuroscience, Amsterdam, The Netherlands
| | - Caroline Mijnsbergen
- Department of (Neuro)Pathology, Amsterdam UMC, University of Amsterdam, Amsterdam Neuroscience, Amsterdam, The Netherlands
| | - Jasper J Anink
- Department of (Neuro)Pathology, Amsterdam UMC, University of Amsterdam, Amsterdam Neuroscience, Amsterdam, The Netherlands
| | - Nam Suk Sim
- Graduate School of Medical Science and Engineering, Korea Advanced Institute of Science and Technology (KAIST), Daejeon, Republic of Korea
| | - Iliana Michailidou
- Department of Clinical Genetics, Leiden University Medical Centre, Leiden, The Netherlands
| | - Floor E Jansen
- Department of Paediatric Neurology, University Medical Center Utrecht, Utrecht, The Netherlands
| | - Peter C van Rijen
- Department of Neurosurgery, Brain Center, Rudolf Magnus Institute for Neuroscience, University Medical Center Utrecht, Utrecht, The Netherlands
| | - Jeong Ho Lee
- Graduate School of Medical Science and Engineering, Korea Advanced Institute of Science and Technology (KAIST), Daejeon, Republic of Korea.,SoVarGen, Inc, Daejeon, Republic of Korea
| | - Liesbeth François
- Neurosciences Therapeutic Area, UCB Pharma, Braine-l'Alleud, Belgium
| | - Jonathan van Eyll
- Neurosciences Therapeutic Area, UCB Pharma, Braine-l'Alleud, Belgium
| | - Stefanie Dedeurwaerdere
- Neurosciences Therapeutic Area, UCB Pharma, Braine-l'Alleud, Belgium.,Department of Translational Neuroscience, University of Antwerp, Wilrijk, Belgium
| | - Erwin A van Vliet
- Department of (Neuro)Pathology, Amsterdam UMC, University of Amsterdam, Amsterdam Neuroscience, Amsterdam, The Netherlands.,Swammerdam Institute for Life Sciences, Center for Neuroscience, University of Amsterdam, Amsterdam, The Netherlands
| | - Angelika Mühlebner
- Department of (Neuro)Pathology, Amsterdam UMC, University of Amsterdam, Amsterdam Neuroscience, Amsterdam, The Netherlands.,Department of Pathology, University Medical Center Utrecht, Utrecht, The Netherlands
| | - James D Mills
- Department of (Neuro)Pathology, Amsterdam UMC, University of Amsterdam, Amsterdam Neuroscience, Amsterdam, The Netherlands.,Department of Clinical and Experimental Epilepsy, UCL, London, UK.,Chalfont Centre for Epilepsy, Chalfont St Peter, UK
| | - Eleonora Aronica
- Department of (Neuro)Pathology, Amsterdam UMC, University of Amsterdam, Amsterdam Neuroscience, Amsterdam, The Netherlands.,Stichting Epilepsie Instellingen Nederland (SEIN), Heemstede, The Netherlands
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21
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Mühlebner A, van Scheppingen J, de Neef A, Bongaarts A, Zimmer TS, Mills JD, Jansen FE, Spliet WGM, Krsek P, Zamecnik J, Coras R, Blumcke I, Feucht M, Scholl T, Gruber VE, Hainfellner JA, Söylemezoğlu F, Kotulska K, Lagae L, Jansen AC, Kwiatkowski DJ, Jozwiak S, Curatolo P, Aronica E. Myelin Pathology Beyond White Matter in Tuberous Sclerosis Complex (TSC) Cortical Tubers. J Neuropathol Exp Neurol 2021; 79:1054-1064. [PMID: 32954437 PMCID: PMC7559237 DOI: 10.1093/jnen/nlaa090] [Citation(s) in RCA: 22] [Impact Index Per Article: 7.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/06/2023] Open
Abstract
Tuberous sclerosis complex (TSC) is a monogenetic disease that arises due to mutations in either the TSC1 or TSC2 gene and affects multiple organ systems. One of the hallmark manifestations of TSC are cortical malformations referred to as cortical tubers. These tubers are frequently associated with treatment-resistant epilepsy. Some of these patients are candidates for epilepsy surgery. White matter abnormalities, such as loss of myelin and oligodendroglia, have been described in a small subset of resected tubers but mechanisms underlying this phenomenon are unclear. Herein, we analyzed a variety of neuropathologic and immunohistochemical features in gray and white matter areas of resected cortical tubers from 46 TSC patients using semi-automated quantitative image analysis. We observed divergent amounts of myelin basic protein as well as numbers of oligodendroglia in both gray and white matter when compared with matched controls. Analyses of clinical data indicated that reduced numbers of oligodendroglia were associated with lower numbers on the intelligence quotient scale and that lower amounts of myelin-associated oligodendrocyte basic protein were associated with the presence of autism-spectrum disorder. In conclusion, myelin pathology in cortical tubers extends beyond the white matter and may be linked to cognitive dysfunction in TSC patients.
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Affiliation(s)
- Angelika Mühlebner
- Department of (Neuro)Pathology, Amsterdam Neuroscience, Amsterdam UMC, University of Amsterdam, Amsterdam, The Netherlands
| | - Jackelien van Scheppingen
- Department of (Neuro)Pathology, Amsterdam Neuroscience, Amsterdam UMC, University of Amsterdam, Amsterdam, The Netherlands
| | - Andrew de Neef
- Department of (Neuro)Pathology, Amsterdam Neuroscience, Amsterdam UMC, University of Amsterdam, Amsterdam, The Netherlands
| | - Anika Bongaarts
- Department of (Neuro)Pathology, Amsterdam Neuroscience, Amsterdam UMC, University of Amsterdam, Amsterdam, The Netherlands
| | - Till S Zimmer
- Department of (Neuro)Pathology, Amsterdam Neuroscience, Amsterdam UMC, University of Amsterdam, Amsterdam, The Netherlands
| | - James D Mills
- Department of (Neuro)Pathology, Amsterdam Neuroscience, Amsterdam UMC, University of Amsterdam, Amsterdam, The Netherlands
| | - Floor E Jansen
- Department of Pediatric Neurology, Brain Center University Medical Center
| | - Wim G M Spliet
- Department of Pathology, University Medical Center Utrecht (WGMS) Utrecht, The Netherlands
| | | | | | - Roland Coras
- Second Faculty of Medicine, Charles University, Motol University Hospital, Prague, Czech Republic; Department of Neuropathology, University Hospital Erlangen, Erlangen, Germany
| | - Ingmar Blumcke
- Second Faculty of Medicine, Charles University, Motol University Hospital, Prague, Czech Republic; Department of Neuropathology, University Hospital Erlangen, Erlangen, Germany
| | | | | | | | | | - Figen Söylemezoğlu
- Medical University of Vienna, Vienna, Austria; Department of Pathology, Faculty of Medicine, Hacettepe University, Ankara, Turkey
| | - Katarzyna Kotulska
- Department of Neurology and Epileptology, The Children's Memorial Health Institute, Warsaw, Poland
| | - Lieven Lagae
- Department of Development and Regeneration-Section Pediatric Neurology, University Hospitals KU Leuven, Leuven
| | - Anna C Jansen
- Pediatric Neurology Unit-UZ Brussel, Brussels Belgium
| | | | - Sergiusz Jozwiak
- Department of Neurology and Epileptology, The Children's Memorial Health Institute.,Department of Child Neurology, Medical University of Warsaw Warsaw, Poland
| | - Paolo Curatolo
- Child Neurology and Psychiatry Unit, Systems Medicine Department, Tor Vergata University, Rome, Italy
| | - Eleonora Aronica
- Department of (Neuro)Pathology, Amsterdam Neuroscience, Amsterdam UMC, University of Amsterdam, Amsterdam, The Netherlands.,Stichting Epilepsie Instellingen Nederland (SEIN), Heemstede, The Netherlands
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22
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Wang Z, Huang K, Yang X, Shen K, Yang L, Ruan R, Shi X, Wang M, Zhu G, Yang M, Zhang C, Lv S, Yang H, Fan X, Liu S. Downregulated GPR30 expression in the epileptogenic foci of female patients with focal cortical dysplasia type IIb and tuberous sclerosis complex is correlated with 18 F-FDG PET-CT values. Brain Pathol 2021; 31:346-364. [PMID: 33314369 PMCID: PMC8018162 DOI: 10.1111/bpa.12925] [Citation(s) in RCA: 11] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/15/2020] [Revised: 11/20/2020] [Accepted: 12/07/2020] [Indexed: 01/19/2023] Open
Abstract
Focal cortical dysplasia type IIb (FCDIIb) and tuberous sclerosis complex (TSC) are typical causes of developmental delay and refractory epilepsy. G‐protein‐coupled receptor 30 (GPR30) is a specific estrogen receptor that is critical in neurodevelopment, neuroinflammation, and neuronal excitability, suggesting that it plays a potential role in the epilepsy of patients with FCDIIb and TSC. Therefore, we investigated the role of GPR30 in patients with FCDIIb and TSC. We found that the expression of GPR30 and its downstream protein kinase A (PKA) pathway were decreased and negatively correlated with seizure frequency in female patients with FCDIIb and TSC, but not in male patients. GPR30 was widely distributed in neurons, astrocytes, and microglia, and its downregulation was especially notable in microglia. The GPR30 agonist G‐1 increased the expression of PKA and p‐PKA in cultured cortical neurons, and the GPR30 antagonist G‐15 exhibited the opposite effects of G‐1. The NF‐κB signaling pathway was also activated in the specimens of female patients with FCDIIb and TSC, and was regulated by G‐1 and G‐15 in cultured cortical neurons. We also found that GPR30 regulated cortical neuronal excitability by altering the frequency of spontaneous excitatory postsynaptic currents and the expression of NR2A/B. Further, the relationship between GPR30 and glycometabolism was evaluated by analyzing the correlations between GPR30 and 18F‐FDG PET‐CT values (standardized uptake values, SUVs). Positive correlations between GPR30 and SUVs were found in female patients, but not in male patients. Intriguingly, GPR30 expression and SUVs were significantly decreased in the epileptogenic tubers of female TSC patients, and ROC curves indicated that SUVs could predict the localization of epileptogenic tubers. Taken together, our results suggest a potential protective effect of GPR30 in the epileptogenesis of female patients with FCDIIb and TSC.
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Affiliation(s)
- Zhongke Wang
- Epilepsy Research Center of PLA, Department of Neurosurgery, Xinqiao Hospital, Army Medical University (Third Military Medical University), Chongqing, China
| | - Kaixuan Huang
- Epilepsy Research Center of PLA, Department of Neurosurgery, Xinqiao Hospital, Army Medical University (Third Military Medical University), Chongqing, China
| | - Xiaolin Yang
- Epilepsy Research Center of PLA, Department of Neurosurgery, Xinqiao Hospital, Army Medical University (Third Military Medical University), Chongqing, China
| | - Kaifeng Shen
- Epilepsy Research Center of PLA, Department of Neurosurgery, Xinqiao Hospital, Army Medical University (Third Military Medical University), Chongqing, China
| | - Ling Yang
- Department of Developmental Neuropsychology, School of Psychology, Army Medical University (Third Military Medical University), Chongqing, China
| | - Ruotong Ruan
- Department of Basic Medical College, Army Medical University (Third Military Medical University), Chongqing, China
| | - Xianjun Shi
- Epilepsy Research Center of PLA, Department of Neurosurgery, Xinqiao Hospital, Army Medical University (Third Military Medical University), Chongqing, China
| | - Miao Wang
- Epilepsy Research Center of PLA, Department of Neurosurgery, Xinqiao Hospital, Army Medical University (Third Military Medical University), Chongqing, China
| | - Gang Zhu
- Epilepsy Research Center of PLA, Department of Neurosurgery, Xinqiao Hospital, Army Medical University (Third Military Medical University), Chongqing, China
| | - Meihua Yang
- Epilepsy Research Center of PLA, Department of Neurosurgery, Xinqiao Hospital, Army Medical University (Third Military Medical University), Chongqing, China
| | - Chunqing Zhang
- Epilepsy Research Center of PLA, Department of Neurosurgery, Xinqiao Hospital, Army Medical University (Third Military Medical University), Chongqing, China
| | - Shengqing Lv
- Epilepsy Research Center of PLA, Department of Neurosurgery, Xinqiao Hospital, Army Medical University (Third Military Medical University), Chongqing, China
| | - Hui Yang
- Epilepsy Research Center of PLA, Department of Neurosurgery, Xinqiao Hospital, Army Medical University (Third Military Medical University), Chongqing, China
| | - Xiaotang Fan
- Department of Developmental Neuropsychology, School of Psychology, Army Medical University (Third Military Medical University), Chongqing, China
| | - Shiyong Liu
- Epilepsy Research Center of PLA, Department of Neurosurgery, Xinqiao Hospital, Army Medical University (Third Military Medical University), Chongqing, China
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23
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Deficiency of Microglial Autophagy Increases the Density of Oligodendrocytes and Susceptibility to Severe Forms of Seizures. eNeuro 2021; 8:ENEURO.0183-20.2021. [PMID: 33472865 PMCID: PMC7890520 DOI: 10.1523/eneuro.0183-20.2021] [Citation(s) in RCA: 7] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/07/2020] [Revised: 12/11/2020] [Accepted: 01/02/2021] [Indexed: 12/14/2022] Open
Abstract
Excessive activation of mTOR in microglia impairs CNS homeostasis and causes severe epilepsy. Autophagy constitutes an important part of mTOR signaling. The contribution of microglial autophagy to CNS homeostasis and epilepsy remains to be determined. Here, we report that ATG7KO mice deficient for autophagy in microglia display a marked increase of myelination markers, a higher density of mature oligodendrocytes (ODCs), and altered lengths of the nodes of Ranvier. Moreover, we found that deficiency of microglial autophagy (ATG7KO) leads to increased seizure susceptibility in three seizure models (pilocarpine, kainic acid, and amygdala kindling). We demonstrated that ATG7KO mice develop severe generalized seizures and display nearly 100% mortality to convulsions induced by pilocarpine and kainic acid. In the amygdala kindling model, we observed significant facilitation of contralateral propagation of seizures, a process underlying the development of generalized seizures. Taken together, our results reveal impaired microglial autophagy as a novel mechanism underlying altered homeostasis of ODCs and increased susceptibility to severe and fatal generalized seizures.
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24
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Scholl T, Gruber VE, Samueli S, Lehner R, Kasprian G, Czech T, Reinten RJ, Hoogendijk L, Hainfellner JA, Aronica E, Mühlebner A, Feucht M. Neurite Outgrowth Inhibitor (NogoA) Is Upregulated in White Matter Lesions of Complex Cortical Malformations. J Neuropathol Exp Neurol 2021; 80:274-282. [PMID: 33517425 DOI: 10.1093/jnen/nlaa159] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/14/2022] Open
Abstract
Complex cortical malformations (CCMs), such as hemimegalencephaly and polymicrogyria, are associated with drug-resistant epilepsy and developmental impairment. They share certain neuropathological characteristics including mammalian target of rapamycin (mTOR) activation and an atypical number of white matter neurons. To get a better understanding of the pathobiology of the lesion architecture, we investigated the role of neurite outgrowth inhibitor A (NogoA), a known regulator of neuronal migration. Epilepsy surgery specimens from 16 CCM patients were analyzed and compared with sections of focal cortical dysplasia IIB (FCD IIB, n = 22), tuberous sclerosis complex (TSC, n = 8) as well as healthy controls (n = 15). Immunohistochemistry was used to characterize NogoA, myelination, and mTOR signaling. Digital slides were evaluated automatically with ImageJ. NogoA staining showed a significantly higher expression within the white matter of CCM and FCD IIB, whereas cortical tubers presented levels similar to controls. Further analysis of possible associations of NogoA with other factors revealed a positive correlation with mTOR and seizure frequency. To identify the main expressing NogoA cell type, double staining revealed dysmorphic neuronal white matter cells. Increased NogoA expression is associated with profound inhibition of neuritic sprouting and therefore contributes to a decrease in neuronal network complexity in CCM patients.
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Affiliation(s)
- Theresa Scholl
- From the Department of Pediatrics and Adolescent Medicine, Medical University of Vienna, Vienna, Austria
| | - Victoria-Elisabeth Gruber
- From the Department of Pediatrics and Adolescent Medicine, Medical University of Vienna, Vienna, Austria
| | - Sharon Samueli
- From the Department of Pediatrics and Adolescent Medicine, Medical University of Vienna, Vienna, Austria
| | - Reinhard Lehner
- Institute of Medical Genetics, Medical University of Vienna, Vienna, Austria
| | - Gregor Kasprian
- Department of Biomedical Imaging and Image-guided Therapy, Medical University of Vienna, Vienna, Austria
| | - Thomas Czech
- Department of Neurosurgery, Medical University of Vienna, Vienna, Austria
| | - Roy J Reinten
- Department of Neuropathology, Amsterdam UMC, University of Amsterdam, Amsterdam, The Netherlands
| | - Lisette Hoogendijk
- Department of Neuropathology, Amsterdam UMC, University of Amsterdam, Amsterdam, The Netherlands
| | - Johannes A Hainfellner
- Division of Neuropathology and Neurochemistry, Department of Neurology, Medical University of Vienna, Vienna, Austria
| | - Eleonora Aronica
- Department of Neuropathology, Amsterdam UMC, University of Amsterdam, Amsterdam, The Netherlands.,Stichting Epilepsie Instellingen Nederland (SEIN), Zwolle, The Netherlands
| | - Angelika Mühlebner
- Department of Neuropathology, Amsterdam UMC, University of Amsterdam, Amsterdam, The Netherlands
| | - Martha Feucht
- From the Department of Pediatrics and Adolescent Medicine, Medical University of Vienna, Vienna, Austria
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25
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de Curtis M, Garbelli R, Uva L. A hypothesis for the role of axon demyelination in seizure generation. Epilepsia 2021; 62:583-595. [PMID: 33493363 DOI: 10.1111/epi.16824] [Citation(s) in RCA: 23] [Impact Index Per Article: 7.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/03/2020] [Revised: 01/04/2021] [Accepted: 01/05/2021] [Indexed: 01/06/2023]
Abstract
Loss of myelin and altered oligodendrocyte distribution in the cerebral cortex are commonly observed both in postsurgical tissue derived from different focal epilepsies (such as focal cortical dysplasias and tuberous sclerosis) and in animal models of focal epilepsy. Moreover, seizures are a frequent symptom in demyelinating diseases, such as multiple sclerosis, and in animal models of demyelination and oligodendrocyte dysfunction. Finally, the excessive activity reported in demyelinated axons may promote hyperexcitability. We hypothesize that the extracellular potassium rise generated during epileptiform activity may be amplified by the presence of axons without appropriate myelin coating and by alterations in oligodendrocyte function. This process could facilitate the triggering of recurrent spontaneous seizures in areas of altered myelination and could result in further demyelination, thus promoting epileptogenesis.
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Affiliation(s)
- Marco de Curtis
- Epilepsy Unit, IRCCS Foundation Carlo Besta Neurological Institute, Milan, Italy
| | - Rita Garbelli
- Epilepsy Unit, IRCCS Foundation Carlo Besta Neurological Institute, Milan, Italy
| | - Laura Uva
- Epilepsy Unit, IRCCS Foundation Carlo Besta Neurological Institute, Milan, Italy
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26
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Neuron-Glia Interactions in Tuberous Sclerosis Complex Affect the Synaptic Balance in 2D and Organoid Cultures. Cells 2021; 10:cells10010134. [PMID: 33445520 PMCID: PMC7826837 DOI: 10.3390/cells10010134] [Citation(s) in RCA: 10] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/14/2020] [Revised: 01/05/2021] [Accepted: 01/08/2021] [Indexed: 02/06/2023] Open
Abstract
Tuberous sclerosis complex (TSC) is a genetic disease affecting the brain. Neurological symptoms like epilepsy and neurodevelopmental issues cause a significant burden on patients. Both neurons and glial cells are affected by TSC mutations. Previous studies have shown changes in the excitation/inhibition balance (E/I balance) in TSC. Astrocytes are known to be important for neuronal development, and astrocytic dysfunction can cause changes in the E/I balance. We hypothesized that astrocytes affect the synaptic balance in TSC. TSC patient-derived stem cells were differentiated into astrocytes, which showed increased proliferation compared to control astrocytes. RNA sequencing revealed changes in gene expression, which were related to epidermal growth factor (EGF) signaling and enriched for genes that coded for secreted or transmembrane proteins. Control neurons were cultured in astrocyte-conditioned medium (ACM) of TSC and control astrocytes. After culture in TSC ACM, neurons showed an altered synaptic balance, with an increase in the percentage of VGAT+ synapses. These findings were confirmed in organoids, presenting a spontaneous 3D organization of neurons and glial cells. To conclude, this study shows that TSC astrocytes are affected and secrete factors that alter the synaptic balance. As an altered E/I balance may underlie many of the neurological TSC symptoms, astrocytes may provide new therapeutic targets.
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27
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De Ridder J, Lavanga M, Verhelle B, Vervisch J, Lemmens K, Kotulska K, Moavero R, Curatolo P, Weschke B, Riney K, Feucht M, Krsek P, Nabbout R, Jansen AC, Wojdan K, Domanska-Pakieła D, Kaczorowska-Frontczak M, Hertzberg C, Ferrier CH, Samueli S, Benova B, Aronica E, Kwiatkowski DJ, Jansen FE, Jóźwiak S, Van Huffel S, Lagae L. Prediction of Neurodevelopment in Infants With Tuberous Sclerosis Complex Using Early EEG Characteristics. Front Neurol 2020; 11:582891. [PMID: 33178126 PMCID: PMC7596378 DOI: 10.3389/fneur.2020.582891] [Citation(s) in RCA: 14] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/13/2020] [Accepted: 08/27/2020] [Indexed: 12/31/2022] Open
Abstract
Tuberous Sclerosis Complex (TSC) is a multisystem genetic disorder with a high risk of early-onset epilepsy and a high prevalence of neurodevelopmental comorbidities, including intellectual disability and autism spectrum disorder (ASD). Therefore, TSC is an interesting disease model to investigate early biomarkers of neurodevelopmental comorbidities when interventions are favourable. We investigated whether early EEG characteristics can be used to predict neurodevelopment in infants with TSC. The first recorded EEG of 64 infants with TSC, enrolled in the international prospective EPISTOP trial (recorded at a median gestational age 42 4/7 weeks) was first visually assessed. EEG characteristics were correlated with ASD risk based on the ADOS-2 score, and cognitive, language, and motor developmental quotients (Bayley Scales of Infant and Toddler Development III) at the age of 24 months. Quantitative EEG analysis was used to validate the relationship between EEG background abnormalities and ASD risk. An abnormal first EEG (OR = 4.1, p-value = 0.027) and more specifically a dysmature EEG background (OR = 4.6, p-value = 0.017) was associated with a higher probability of ASD traits at the age of 24 months. This association between an early abnormal EEG and ASD risk remained significant in a multivariable model, adjusting for mutation and treatment (adjusted OR = 4.2, p-value = 0.029). A dysmature EEG background was also associated with lower cognitive (p-value = 0.029), language (p-value = 0.001), and motor (p-value = 0.017) developmental quotients at the age of 24 months. Our findings suggest that early EEG characteristics in newborns and infants with TSC can be used to predict neurodevelopmental comorbidities.
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Affiliation(s)
- Jessie De Ridder
- Pediatric Neurology, Department of Development and Regeneration, University of Leuven KU Leuven, Leuven, Belgium
| | - Mario Lavanga
- Department of Electrical Engineering (ESAT), STADIUS Centre for Dynamical Systems, Signal Processing and Data Analytics, KU Leuven, Leuven, Belgium
| | - Birgit Verhelle
- Pediatric Neurology, Department of Development and Regeneration, University of Leuven KU Leuven, Leuven, Belgium
| | - Jan Vervisch
- Pediatric Neurology, Department of Development and Regeneration, University of Leuven KU Leuven, Leuven, Belgium
| | - Katrien Lemmens
- Pediatric Neurology, Department of Development and Regeneration, University of Leuven KU Leuven, Leuven, Belgium
| | - Katarzyna Kotulska
- Department of Neurology and Epileptology, The Children's Memorial Health Institute, Warsaw, Poland
| | - Romina Moavero
- Child Neurology and Psychiatry Unit, Systems Medicine Department, Tor Vergata University, Rome, Italy.,Child Neurology Unit, Neuroscience and Neurorehabilitation Department, "Bambino Gesù" Children's Hospital, Rome, Italy
| | - Paolo Curatolo
- Child Neurology and Psychiatry Unit, Systems Medicine Department, Tor Vergata University, Rome, Italy
| | - Bernhard Weschke
- Department of Child Neurology, Charité University Medicine Berlin, Berlin, Germany
| | - Kate Riney
- Neuroscience Unit, Queensland Children's Hospital, Brisbane, QLD, Australia.,University of Queensland School of Clinical Medicine, Brisbane, QLD, Australia
| | - Martha Feucht
- Department of Pediatrics, Medical University Vienna, Vienna, Austria
| | - Pavel Krsek
- Department of Paediatric Neurology, Charles University, Second Faculty of Medicine, Motol University Hospital, Prague, Czechia
| | - Rima Nabbout
- Department of Pediatric Neurology, Reference Centre for Rare Epilepsies, Imagine Institute, Necker- Enfants Malades Hospital, University Paris Descartes, Paris, France
| | - Anna C Jansen
- Pediatric Neurology Unit, Universitair Ziekenhuis Brussel, Brussels, Belgium
| | - Konrad Wojdan
- Transition Technologies, Warsaw, Poland.,Institute of Heat Engineering, Warsaw University and Technology, Warsaw, Poland
| | - Dorota Domanska-Pakieła
- Department of Neurology and Epileptology, The Children's Memorial Health Institute, Warsaw, Poland
| | | | - Christoph Hertzberg
- Diagnose und Behandlungszentrum für Kinder und Jugendliche, Vivantes Klinikum Neuköln, Berlin, Germany
| | - Cyrille H Ferrier
- Department of Child Neurology, Brain Centre, University Medical Centre Utrecht, Utrecht, Netherlands
| | - Sharon Samueli
- Department of Pediatrics, Medical University Vienna, Vienna, Austria
| | - Barbora Benova
- Department of Paediatric Neurology, Charles University, Second Faculty of Medicine, Motol University Hospital, Prague, Czechia
| | - Eleonora Aronica
- Department of (Neuro)Pathology, Amsterdam Universitair Medisch Centrum, University of Amsterdam, Amsterdam, Netherlands.,Stichting Epilepsie Instellingen Nederland (SEIN), Heemstede, Netherlands
| | - David J Kwiatkowski
- Harvard Medical School, Brigham and Women's Hospital, Boston, MA, United States
| | - Floor E Jansen
- Department of Child Neurology, Brain Centre, University Medical Centre Utrecht, Utrecht, Netherlands
| | - Sergiusz Jóźwiak
- Department of Neurology and Epileptology, The Children's Memorial Health Institute, Warsaw, Poland.,Department of Child Neurology, Medical University of Warsaw, Warsaw, Poland
| | - Sabine Van Huffel
- Department of Electrical Engineering (ESAT), STADIUS Centre for Dynamical Systems, Signal Processing and Data Analytics, KU Leuven, Leuven, Belgium
| | - Lieven Lagae
- Pediatric Neurology, Department of Development and Regeneration, University of Leuven KU Leuven, Leuven, Belgium
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28
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Lee HM, Gill RS, Fadaie F, Cho KH, Guiot MC, Hong SJ, Bernasconi N, Bernasconi A. Unsupervised machine learning reveals lesional variability in focal cortical dysplasia at mesoscopic scale. NEUROIMAGE-CLINICAL 2020; 28:102438. [PMID: 32987299 PMCID: PMC7520429 DOI: 10.1016/j.nicl.2020.102438] [Citation(s) in RCA: 8] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 07/21/2020] [Revised: 09/10/2020] [Accepted: 09/14/2020] [Indexed: 02/03/2023]
Abstract
Consensus clustering of MRI contrasts maps focal cortical dysplasia lesional variability. Lesions were parcellated into four classes with distinct structural profiles. FCD classes reflected typical functional and histopathological characteristics. Class membership was replicated in two independent datasets. Class-informed detection algorithm outperformed a class-naïve paradigm.
Objective Focal cortical dysplasia (FCD) is the most common epileptogenic developmental malformation and a prevalent cause of surgically amenable epilepsy. While cellular and molecular biology data suggest that FCD lesional characteristics lie along a spectrum, this notion remains to be verified in vivo. We tested the hypothesis that machine learning applied to MRI captures FCD lesional variability at a mesoscopic scale. Methods We studied 46 patients with histologically verified FCD Type II and 35 age- and sex-matched healthy controls. We applied consensus clustering, an unsupervised learning technique that identifies stable clusters based on bootstrap-aggregation, to 3 T multicontrast MRI (T1-weighted MRI and FLAIR) features of FCD normalized with respect to distributions in controls. Results Lesions were parcellated into four classes with distinct structural profiles variably expressed within and across patients: Class-1 with isolated white matter (WM) damage; Class-2 combining grey matter (GM) and WM alterations; Class-3 with isolated GM damage; Class-4 with GM-WM interface anomalies. Class membership was replicated in two independent datasets. Classes with GM anomalies impacted local function (resting-state fMRI derived ALFF), while those with abnormal WM affected large-scale connectivity (assessed by degree centrality). Overall, MRI classes reflected typical histopathological FCD characteristics: Class-1 was associated with severe WM gliosis and interface blurring, Class-2 with severe GM dyslamination and moderate WM gliosis, Class-3 with moderate GM gliosis, Class-4 with mild interface blurring. A detection algorithm trained on class-informed data outperformed a class-naïve paradigm. Significance Machine learning applied to widely available MRI contrasts uncovers FCD Type II variability at a mesoscopic scale and identifies tissue classes with distinct structural dimensions, functional and histopathological profiles. Integrating in vivo staging of FCD traits with automated lesion detection is likely to inform the development of novel personalized treatments.
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Affiliation(s)
- Hyo M Lee
- Neuroimaging of Epilepsy Laboratory, Montreal Neurological Institute and Hospital, McGill University, Montreal, Quebec, Canada
| | - Ravnoor S Gill
- Neuroimaging of Epilepsy Laboratory, Montreal Neurological Institute and Hospital, McGill University, Montreal, Quebec, Canada
| | - Fatemeh Fadaie
- Neuroimaging of Epilepsy Laboratory, Montreal Neurological Institute and Hospital, McGill University, Montreal, Quebec, Canada
| | - Kyoo H Cho
- Department of Neurology, Yonsei University College of Medicine, Seoul, South Korea
| | - Marie C Guiot
- Department of Pathology, Montreal Neurological Institute and Hospital, McGill University, Montreal, Quebec, Canada
| | - Seok-Jun Hong
- Neuroimaging of Epilepsy Laboratory, Montreal Neurological Institute and Hospital, McGill University, Montreal, Quebec, Canada
| | - Neda Bernasconi
- Neuroimaging of Epilepsy Laboratory, Montreal Neurological Institute and Hospital, McGill University, Montreal, Quebec, Canada
| | - Andrea Bernasconi
- Neuroimaging of Epilepsy Laboratory, Montreal Neurological Institute and Hospital, McGill University, Montreal, Quebec, Canada.
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Zimmer TS, Broekaart DWM, Gruber VE, van Vliet EA, Mühlebner A, Aronica E. Tuberous Sclerosis Complex as Disease Model for Investigating mTOR-Related Gliopathy During Epileptogenesis. Front Neurol 2020; 11:1028. [PMID: 33041976 PMCID: PMC7527496 DOI: 10.3389/fneur.2020.01028] [Citation(s) in RCA: 22] [Impact Index Per Article: 5.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/07/2020] [Accepted: 08/06/2020] [Indexed: 12/13/2022] Open
Abstract
Tuberous sclerosis complex (TSC) represents the prototypic monogenic disorder of the mammalian target of rapamycin (mTOR) pathway dysregulation. It provides the rational mechanistic basis of a direct link between gene mutation and brain pathology (structural and functional abnormalities) associated with a complex clinical phenotype including epilepsy, autism, and intellectual disability. So far, research conducted in TSC has been largely neuron-oriented. However, the neuropathological hallmarks of TSC and other malformations of cortical development also include major morphological and functional changes in glial cells involving astrocytes, oligodendrocytes, NG2 glia, and microglia. These cells and their interglial crosstalk may offer new insights into the common neurobiological mechanisms underlying epilepsy and the complex cognitive and behavioral comorbidities that are characteristic of the spectrum of mTOR-associated neurodevelopmental disorders. This review will focus on the role of glial dysfunction, the interaction between glia related to mTOR hyperactivity, and its contribution to epileptogenesis in TSC. Moreover, we will discuss how understanding glial abnormalities in TSC might give valuable insight into the pathophysiological mechanisms that could help to develop novel therapeutic approaches for TSC or other pathologies characterized by glial dysfunction and acquired mTOR hyperactivation.
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Affiliation(s)
- Till S Zimmer
- Department of (Neuro)Pathology, Amsterdam Neuroscience, Amsterdam University Medical Centers, University of Amsterdam, Amsterdam, Netherlands
| | - Diede W M Broekaart
- Department of (Neuro)Pathology, Amsterdam Neuroscience, Amsterdam University Medical Centers, University of Amsterdam, Amsterdam, Netherlands
| | | | - Erwin A van Vliet
- Department of (Neuro)Pathology, Amsterdam Neuroscience, Amsterdam University Medical Centers, University of Amsterdam, Amsterdam, Netherlands.,Swammerdam Institute for Life Sciences, Center for Neuroscience, University of Amsterdam, Amsterdam, Netherlands
| | - Angelika Mühlebner
- Department of (Neuro)Pathology, Amsterdam Neuroscience, Amsterdam University Medical Centers, University of Amsterdam, Amsterdam, Netherlands
| | - Eleonora Aronica
- Department of (Neuro)Pathology, Amsterdam Neuroscience, Amsterdam University Medical Centers, University of Amsterdam, Amsterdam, Netherlands.,Stichting Epilepsie Instellingen Nederland (SEIN), Heemstede, Netherlands
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30
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On the merits of non-invasive myelin imaging in epilepsy, a literature review. J Neurosci Methods 2020; 338:108687. [DOI: 10.1016/j.jneumeth.2020.108687] [Citation(s) in RCA: 19] [Impact Index Per Article: 4.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/15/2020] [Revised: 03/09/2020] [Accepted: 03/11/2020] [Indexed: 01/10/2023]
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31
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Zimmer TS, Ciriminna G, Arena A, Anink JJ, Korotkov A, Jansen FE, van Hecke W, Spliet WG, van Rijen PC, Baayen JC, Idema S, Rensing NR, Wong M, Mills JD, van Vliet EA, Aronica E. Chronic activation of anti-oxidant pathways and iron accumulation in epileptogenic malformations. Neuropathol Appl Neurobiol 2020; 46:546-563. [PMID: 31869431 PMCID: PMC7308211 DOI: 10.1111/nan.12596] [Citation(s) in RCA: 18] [Impact Index Per Article: 4.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/15/2019] [Accepted: 12/18/2019] [Indexed: 12/29/2022]
Abstract
Aims Oxidative stress is evident in resected epileptogenic brain tissue of patients with developmental brain malformations related to mammalian target of rapamycin activation: tuberous sclerosis complex (TSC) and focal cortical dysplasia type IIb (FCD IIb). Whether chronic activation of anti‐oxidant pathways is beneficial or contributes to pathology is not clear. Methods We investigated oxidative stress markers, including haem oxygenase 1, ferritin and the inflammation associated microRNA‐155 in surgically resected epileptogenic brain tissue of TSC (n = 10) and FCD IIb (n = 8) patients and in a TSC model (Tsc1GFAP−/− mice) using immunohistochemistry, in situ hybridization, real‐time quantitative PCR and immunoblotting. Using human foetal astrocytes we performed an in vitro characterization of the anti‐oxidant response to acute and chronic oxidative stress and evaluated overexpression of the disease‐relevant pro‐inflammatory microRNA‐155. Results Resected TSC or FCD IIb tissue displayed higher expression of oxidative stress markers and microRNA‐155. Tsc1GFAP−/− mice expressed more microRNA‐155 and haem oxygenase 1 in the brain compared to wild‐type, preceding the typical development of spontaneous seizures in these animals. In vitro, chronic microRNA‐155 overexpression induced haem oxygenase 1, iron regulatory elements and increased susceptibility to oxidative stress. Overexpression of iron regulatory genes was also detected in patients with TSC, FCD IIb and Tsc1GFAP−/− mice. Conclusion Our results demonstrate that early and sustained activation of anti‐oxidant signalling and dysregulation of iron metabolism are a pathological hallmark of FCD IIb and TSC. Our findings suggest novel therapeutic strategies aimed at controlling the pathological link between both processes.
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Affiliation(s)
- T S Zimmer
- Department of (Neuro)Pathology, Amsterdam UMC, University of Amsterdam, Amsterdam Neuroscience, Amsterdam, The Netherlands
| | - G Ciriminna
- Department of (Neuro)Pathology, Amsterdam UMC, University of Amsterdam, Amsterdam Neuroscience, Amsterdam, The Netherlands
| | - A Arena
- Department of (Neuro)Pathology, Amsterdam UMC, University of Amsterdam, Amsterdam Neuroscience, Amsterdam, The Netherlands.,Department of Biochemical Sciences, Sapienza University of Rome, Rome, Italy
| | - J J Anink
- Department of (Neuro)Pathology, Amsterdam UMC, University of Amsterdam, Amsterdam Neuroscience, Amsterdam, The Netherlands
| | - A Korotkov
- Department of (Neuro)Pathology, Amsterdam UMC, University of Amsterdam, Amsterdam Neuroscience, Amsterdam, The Netherlands
| | - F E Jansen
- Department of Paediatric Neurology, University Medical Center Utrecht, The Netherlands
| | - W van Hecke
- Department of Pathology, University Medical Center Utrecht, The Netherlands
| | - W G Spliet
- Department of Pathology, University Medical Center Utrecht, The Netherlands
| | - P C van Rijen
- Department of Neurosurgery, Brain Centre, Rudolf Magnus Institute for Neuroscience, University Medical Center Utrecht, Utrecht, The Netherlands
| | - J C Baayen
- Department of Neurosurgery, Amsterdam UMC, Vrije Universiteit Amsterdam, Amsterdam Neuroscience, Amsterdam, The Netherlands
| | - S Idema
- Department of Neurosurgery, Amsterdam UMC, Vrije Universiteit Amsterdam, Amsterdam Neuroscience, Amsterdam, The Netherlands
| | - N R Rensing
- Department of Neurology, Washington University, Saint Louis, MO, USA
| | - M Wong
- Department of Neurology, Washington University, Saint Louis, MO, USA
| | - J D Mills
- Department of (Neuro)Pathology, Amsterdam UMC, University of Amsterdam, Amsterdam Neuroscience, Amsterdam, The Netherlands
| | - E A van Vliet
- Department of (Neuro)Pathology, Amsterdam UMC, University of Amsterdam, Amsterdam Neuroscience, Amsterdam, The Netherlands.,Center for Neuroscience, Swammerdam Institute for Life Sciences, University of Amsterdam, Amsterdam, The Netherlands
| | - E Aronica
- Department of (Neuro)Pathology, Amsterdam UMC, University of Amsterdam, Amsterdam Neuroscience, Amsterdam, The Netherlands.,Stichting Epilepsie Instellingen Nederland (SEIN), Heemstede, The Netherlands
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32
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Donkels C, Peters M, Fariña Núñez MT, Nakagawa JM, Kirsch M, Vlachos A, Scheiwe C, Schulze-Bonhage A, Prinz M, Beck J, Haas CA. Oligodendrocyte lineage and myelination are compromised in the gray matter of focal cortical dysplasia type IIa. Epilepsia 2019; 61:171-184. [PMID: 31872870 DOI: 10.1111/epi.16415] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/22/2019] [Revised: 11/28/2019] [Accepted: 11/29/2019] [Indexed: 01/26/2023]
Abstract
OBJECTIVES Focal cortical dysplasias (FCDs) are local malformations of the human neocortex and a leading cause of medically intractable epilepsy. FCDs are characterized by local architectural disturbances of the neocortex and often by a blurred gray-white matter boundary indicating abnormal white matter myelination. We have recently shown that myelination is also compromised in the gray matter of dysplastic areas, since transcripts encoding factors for oligodendrocyte differentiation and myelination are downregulated and myelin fibers appear fractured and disorganized. METHODS Here, we characterized the gray matter-associated myelination pathology in detail by in situ hybridization, immunohistochemistry, and electron microscopy with markers for myelin, mature oligodendrocytes, and oligodendrocyte precursor cells in tissue sections of FCD IIa and control cortices. In addition, we isolated oligodendrocyte precursor cells from resected dysplastic tissue and performed proliferation assays. RESULTS We show that the proportion of myelinated gray matter is similar in the dysplastic cortex to that in controls and myelinated fibers extend up to layer III. On the ultrastructural level, however, we found that the myelin sheaths of layer V axons are thinner in dysplastic specimens than in controls. In addition, the density of oligodendrocyte precursor cells and of mature oligodendrocytes was reduced. Finally, we show for the first time that oligodendrocyte precursor cells isolated from resected dysplastic cortex have a reduced proliferation capacity in comparison to controls. SIGNIFICANCE These results indicate that proliferation and differentiation of oligodendrocyte precursor cells and the formation of myelin sheaths are compromised in FCD and might contribute to the epileptogenicity of this cortical malformation.
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Affiliation(s)
- Catharina Donkels
- Experimental Epilepsy Research, Department of Neurosurgery, Medical Center-University of Freiburg, Faculty of Medicine, University of Freiburg, Freiburg, Germany
| | - Myriam Peters
- Experimental Epilepsy Research, Department of Neurosurgery, Medical Center-University of Freiburg, Faculty of Medicine, University of Freiburg, Freiburg, Germany
| | - Mateo T Fariña Núñez
- Department of Neurosurgery, Medical Center-University of Freiburg, Faculty of Medicine, University of Freiburg, Freiburg, Germany
| | - Julia M Nakagawa
- Department of Neurosurgery, Medical Center-University of Freiburg, Faculty of Medicine, University of Freiburg, Freiburg, Germany
| | - Matthias Kirsch
- Department of Neuroanatomy, Institute of Anatomy and Cell Biology, Faculty of Medicine, University of Freiburg, Freiburg, Germany
| | - Andreas Vlachos
- Department of Neuroanatomy, Institute of Anatomy and Cell Biology, Faculty of Medicine, University of Freiburg, Freiburg, Germany.,Center for Basics in NeuroModulation (NeuroModulBasics), Faculty of Medicine, University of Freiburg, Freiburg, Germany
| | - Christian Scheiwe
- Department of Neurosurgery, Medical Center-University of Freiburg, Faculty of Medicine, University of Freiburg, Freiburg, Germany
| | - Andreas Schulze-Bonhage
- Center for Basics in NeuroModulation (NeuroModulBasics), Faculty of Medicine, University of Freiburg, Freiburg, Germany.,Epilepsy Center Freiburg, Medical Center-University of Freiburg, Faculty of Medicine, University of Freiburg, Freiburg, Germany.,BrainLinks-BrainTools, Cluster of Excellence, University of Freiburg, Freiburg, Germany
| | - Marco Prinz
- Center for Basics in NeuroModulation (NeuroModulBasics), Faculty of Medicine, University of Freiburg, Freiburg, Germany.,Institute of Neuropathology, Medical Center-University of Freiburg, Faculty of Medicine, University of Freiburg, Freiburg, Germany.,Signalling Research Centers BIOSS and CIBSS, University of Freiburg, Freiburg, Germany
| | - Jürgen Beck
- Department of Neurosurgery, Medical Center-University of Freiburg, Faculty of Medicine, University of Freiburg, Freiburg, Germany
| | - Carola A Haas
- Experimental Epilepsy Research, Department of Neurosurgery, Medical Center-University of Freiburg, Faculty of Medicine, University of Freiburg, Freiburg, Germany.,Center for Basics in NeuroModulation (NeuroModulBasics), Faculty of Medicine, University of Freiburg, Freiburg, Germany.,BrainLinks-BrainTools, Cluster of Excellence, University of Freiburg, Freiburg, Germany
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33
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Wong M. The role of glia in epilepsy, intellectual disability, and other neurodevelopmental disorders in tuberous sclerosis complex. J Neurodev Disord 2019; 11:30. [PMID: 31838997 PMCID: PMC6913020 DOI: 10.1186/s11689-019-9289-6] [Citation(s) in RCA: 31] [Impact Index Per Article: 6.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 01/03/2019] [Accepted: 11/11/2019] [Indexed: 01/12/2023] Open
Abstract
Background Tuberous sclerosis complex (TSC) is a genetic disorder characterized by severe neurological manifestations, including epilepsy, intellectual disability, autism, and a range of other behavioral and psychiatric symptoms, collectively referred to as TSC-associated neuropsychiatric disorders (TAND). Various tumors and hamartomas affecting different organs are the pathological hallmarks of the disease, especially cortical tubers of the brain, but specific cellular and molecular abnormalities, such as involving the mechanistic target of rapamycin (mTOR) pathway, have been identified that also cause or contribute to neurological manifestations of TSC independent of gross structural lesions. In particular, while neurons are immediate mediators of neurological symptoms, different types of glial cells have been increasingly recognized to play important roles in the phenotypes of TSC. Main body This review summarizes the literature supporting glial dysfunction from both mouse models and clinical studies of TSC. In particular, evidence for the role of astrocytes, microglia, and oligodendrocytes in the pathophysiology of epilepsy and TAND in TSC is analyzed. Therapeutic implications of targeting glia cells in developing novel treatments for the neurological manifestations of TSC are also considered. Conclusions Different types of glial cells have both cell autonomous effects and interactions with neurons and other cells that are involved in the pathophysiology of the neurological phenotype of TSC. Targeting glial-mediated mechanisms may represent a novel therapeutic approach for epilepsy and TAND in TSC patients.
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Affiliation(s)
- Michael Wong
- Department of Neurology and the Hope Center for Neurological Disorders, Washington University School of Medicine, 660 South Euclid Avenue, Box 8111, St. Louis, MO, 63110, USA.
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34
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Veersema TJ, Neef A, Scheppingen J, Ferrier CH, Eijsden P, Gosselaar PH, Rijen PC, Spliet WG, Braun KP, Mühlebner A, Aronica E. Changes in vascular density in resected tissue of 97 patients with mild malformation of cortical development, focal cortical dysplasia or TSC‐related cortical tubers. Int J Dev Neurosci 2019; 79:96-104. [DOI: 10.1016/j.ijdevneu.2019.11.003] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/18/2019] [Revised: 10/13/2019] [Accepted: 11/22/2019] [Indexed: 11/30/2022] Open
Affiliation(s)
- Tim J. Veersema
- Department of Neurology and NeurosurgeryUMC Utrecht Brain CenterUniversity Medical Center UtrechtUtrechtThe Netherlands
| | - Andrew Neef
- Department of (Neuro) PathologyAmsterdam UMCUniversity of AmsterdamAmsterdamThe Netherlands
| | - Jackelien Scheppingen
- Department of (Neuro) PathologyAmsterdam UMCUniversity of AmsterdamAmsterdamThe Netherlands
| | - Cyrille H. Ferrier
- Department of Neurology and NeurosurgeryUMC Utrecht Brain CenterUniversity Medical Center UtrechtUtrechtThe Netherlands
| | - Pieter Eijsden
- Department of Neurology and NeurosurgeryUMC Utrecht Brain CenterUniversity Medical Center UtrechtUtrechtThe Netherlands
| | - Peter H. Gosselaar
- Department of Neurology and NeurosurgeryUMC Utrecht Brain CenterUniversity Medical Center UtrechtUtrechtThe Netherlands
| | - Peter C. Rijen
- Department of Neurology and NeurosurgeryUMC Utrecht Brain CenterUniversity Medical Center UtrechtUtrechtThe Netherlands
| | - Wim G.M. Spliet
- Department of PathologyUniversity Medical Center UtrechtUtrechtThe Netherlands
| | - Kees P.J. Braun
- Department of Neurology and NeurosurgeryUMC Utrecht Brain CenterUniversity Medical Center UtrechtUtrechtThe Netherlands
| | - Angelika Mühlebner
- Department of (Neuro) PathologyAmsterdam UMCUniversity of AmsterdamAmsterdamThe Netherlands
| | - Eleonora Aronica
- Department of (Neuro) PathologyAmsterdam UMCUniversity of AmsterdamAmsterdamThe Netherlands
- Stichting Epilepsie Instellingen Nederland (SEIN)The Netherlands
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Early Postnatal Exposure to Isoflurane Disrupts Oligodendrocyte Development and Myelin Formation in the Mouse Hippocampus. Anesthesiology 2019; 131:1077-1091. [PMID: 31436548 PMCID: PMC6800770 DOI: 10.1097/aln.0000000000002904] [Citation(s) in RCA: 21] [Impact Index Per Article: 4.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/17/2022]
Abstract
BACKGROUND Early postnatal exposure to general anesthetics may interfere with brain development. We tested the hypothesis that isoflurane causes a lasting disruption in myelin development via actions on the mammalian target of rapamycin pathway. METHODS Mice were exposed to 1.5% isoflurane for 4 h at postnatal day 7. The mammalian target of rapamycin inhibitor, rapamycin, or the promyelination drug, clemastine, were administered on days 21 to 35. Mice underwent Y-maze and novel object position recognition tests (n = 12 per group) on days 56 to 62 or were euthanized for either immunohistochemistry (n = 8 per group) or Western blotting (n = 8 per group) at day 35 or were euthanized for electron microscopy at day 63. RESULTS Isoflurane exposure increased the percentage of phospho-S6-positive oligodendrocytes in fimbria of hippocampus from 22 ± 7% to 51 ± 6% (P < 0.0001). In Y-maze testing, isoflurane-exposed mice did not discriminate normally between old and novel arms, spending equal time in both (50 ± 5% old:50 ± 5% novel; P = 0.999), indicating impaired spatial learning. Treatment with clemastine restored discrimination, as evidenced by increased time spent in the novel arm (43 ± 6% old:57 ± 6% novel; P < 0.001), and rapamycin had a similar effect (44 ± 8% old:56 ± 8% novel; P < 0.001). Electron microscopy shows a reduction in myelin thickness as measured by an increase in g-ratio from 0.76 ± 0.06 for controls to 0.79 ± 0.06 for the isoflurane group (P < 0.001). Isoflurane exposure followed by rapamycin treatment resulted in a g-ratio (0.75 ± 0.05) that did not differ significantly from the control value (P = 0.426). Immunohistochemistry and Western blotting show that isoflurane acts on oligodendrocyte precursor cells to inhibit both proliferation and differentiation. DNA methylation and expression of a DNA methyl transferase 1 are reduced in oligodendrocyte precursor cells after isoflurane treatment. Effects of isoflurane on oligodendrocyte precursor cells were abolished by treatment with rapamycin. CONCLUSIONS Early postnatal exposure to isoflurane in mice causes lasting disruptions of oligodendrocyte development in the hippocampus via actions on the mammalian target of rapamycin pathway.
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Mühlebner A, Bongaarts A, Sarnat HB, Scholl T, Aronica E. New insights into a spectrum of developmental malformations related to mTOR dysregulations: challenges and perspectives. J Anat 2019; 235:521-542. [PMID: 30901081 DOI: 10.1111/joa.12956] [Citation(s) in RCA: 41] [Impact Index Per Article: 8.2] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 01/15/2019] [Indexed: 12/20/2022] Open
Abstract
In recent years the role of the mammalian target of rapamycin (mTOR) pathway has emerged as crucial for normal cortical development. Therefore, it is not surprising that aberrant activation of mTOR is associated with developmental malformations and epileptogenesis. A broad spectrum of malformations of cortical development, such as focal cortical dysplasia (FCD) and tuberous sclerosis complex (TSC), have been linked to either germline or somatic mutations in mTOR pathway-related genes, commonly summarised under the umbrella term 'mTORopathies'. However, there are still a number of unanswered questions regarding the involvement of mTOR in the pathophysiology of these abnormalities. Therefore, a monogenetic disease, such as TSC, can be more easily applied as a model to study the mechanisms of epileptogenesis and identify potential new targets of therapy. Developmental neuropathology and genetics demonstrate that FCD IIb and hemimegalencephaly are the same diseases. Constitutive activation of mTOR signalling represents a shared pathogenic mechanism in a group of developmental malformations that have histopathological and clinical features in common, such as epilepsy, autism and other comorbidities. We seek to understand the effect of mTOR dysregulation in a developing cortex with the propensity to generate seizures as well as the aftermath of the surrounding environment, including the white matter.
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Affiliation(s)
- A Mühlebner
- Department of Neuropathology, Amsterdam UMC, University of Amsterdam, Amsterdam, The Netherlands
| | - A Bongaarts
- Department of Neuropathology, Amsterdam UMC, University of Amsterdam, Amsterdam, The Netherlands
| | - H B Sarnat
- Departments of Paediatrics, Pathology (Neuropathology) and Clinical Neurosciences, University of Calgary Cumming School of Medicine and Alberta Children's Hospital Research Institute (Owerko Centre), Calgary, AB, Canada
| | - T Scholl
- Department of Paediatric and Adolescent Medicine, Medical University of Vienna, Vienna, Austria
| | - E Aronica
- Department of Neuropathology, Amsterdam UMC, University of Amsterdam, Amsterdam, The Netherlands.,Stichting Epilepsie Instellingen Nederland (SEIN), Amsterdam, The Netherlands
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37
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Gnatkovsky V, Pelliccia V, de Curtis M, Tassi L. Two main focal seizure patterns revealed by intracerebral electroencephalographic biomarker analysis. Epilepsia 2018; 60:96-106. [DOI: 10.1111/epi.14610] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/06/2018] [Revised: 10/08/2018] [Accepted: 10/29/2018] [Indexed: 02/06/2023]
Affiliation(s)
- Vadym Gnatkovsky
- Epilepsy Unit; Institute of Cure, Recovery, and Scientific Research (IRCCS) Foundation Carlo Besta Neurological Institute; Milan Italy
| | | | - Marco de Curtis
- Epilepsy Unit; Institute of Cure, Recovery, and Scientific Research (IRCCS) Foundation Carlo Besta Neurological Institute; Milan Italy
| | - Laura Tassi
- Claudio Munari Epilepsy Surgery Center; Niguarda Hospital; Milan Italy
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38
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Mata-Mbemba D, Iimura Y, Hazrati LN, Ochi A, Otsubo H, Snead OC, Rutka J, Widjaja E. MRI, Magnetoencephalography, and Surgical Outcome of Oligodendrocytosis versus Focal Cortical Dysplasia Type I. AJNR Am J Neuroradiol 2018; 39:2371-2377. [PMID: 30442696 DOI: 10.3174/ajnr.a5877] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/08/2018] [Accepted: 09/19/2018] [Indexed: 01/09/2023]
Abstract
BACKGROUND AND PURPOSE Abnormalities of oligodendrocytes have been reported in surgical specimens of patients with medically intractable epilepsy. The aim of this study was to compare the MR imaging, magnetoencephalography, and surgical outcome of children with oligodendrocytosis relative to focal cortical dysplasia I. MATERIALS AND METHODS Oligodendrocytosis included oligodendroglial hyperplasia, oligodendrogliosis, and oligodendroglial-like cells in the white matter, gray matter, or both from children with medically intractable epilepsy. Focal cortical dysplasia I included radial and tangential cortical dyslamination. The MR imaging, magnetoencephalography, type of operation, location, and seizure outcome of oligodendrocytosis, focal cortical dysplasia I, and oligodendrocytosis + focal cortical dysplasia I were compared. RESULTS Eighteen subjects (39.1%) had oligodendrocytosis, 21 (45.7%) had focal cortical dysplasia I, and 7 (15.2%) had oligodendrocytosis + focal cortical dysplasia I. There were no significant differences in the type of seizures, focal or nonfocal epileptiform discharges, magnetoencephalography, and MR imaging features, including high T1 signal in the cortex, high T2/FLAIR signal in the cortex or subcortical white matter, increased cortical thickness, blurring of the gray-white junction, or abnormal sulcation and gyration among those with oligodendrocytosis, focal cortical dysplasia I, or oligodendrocytosis + focal cortical dysplasia I (P > .01). There were no significant differences in the extent of resection (unilobar versus multilobar versus hemispherectomy), location of the operation (temporal versus extratemporal versus both), or seizure-free outcome of oligodendrocytosis, focal cortical dysplasia I, and oligodendrocytosis + focal cortical dysplasia I (P > .05). CONCLUSIONS Oligodendrocytosis shared MR imaging and magnetoencephalography features with focal cortical dysplasia I, and multilobar resection was frequently required to achieve seizure freedom. In 15% of cases, concurrent oligodendrocytosis and focal cortical dysplasia I were identified. The findings suggest that oligodendrocytosis may represent a mild spectrum of malformations of cortical development.
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Affiliation(s)
- D Mata-Mbemba
- From the Department of Diagnostic Imaging (D.M.-M., E.W.)
| | - Y Iimura
- Division of Neurology (Y.I., A.O., H.O., O.C.S., E.W.)
| | | | - A Ochi
- Division of Neurology (Y.I., A.O., H.O., O.C.S., E.W.)
| | - H Otsubo
- Division of Neurology (Y.I., A.O., H.O., O.C.S., E.W.)
| | - O C Snead
- Division of Neurology (Y.I., A.O., H.O., O.C.S., E.W.)
| | - J Rutka
- Neurosurgery (J.R.), The Hospital for Sick Children, University of Toronto, Ontario, Canada
| | - E Widjaja
- From the Department of Diagnostic Imaging (D.M.-M., E.W.) .,Division of Neurology (Y.I., A.O., H.O., O.C.S., E.W.)
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39
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MTOR pathway in focal cortical dysplasia type 2: What do we know? Epilepsy Behav 2018; 85:157-163. [PMID: 29945038 DOI: 10.1016/j.yebeh.2018.05.014] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 02/14/2018] [Revised: 05/08/2018] [Accepted: 05/09/2018] [Indexed: 01/15/2023]
Abstract
Focal cortical dysplasia (FCD) is the most commonly encountered developmental malformation that causes refractory epilepsy. Focal cortical dysplasia type 2 is one of the most usual neuropathological findings in tissues resected therapeutically from patients with drug-resistant epilepsy. Unlike other types of FCD, it is characterized by laminar disorganization and dysplastic neurons, which compromise the organization of the six histologically known layers in the cortex; the morphology and/or cell location can also be altered. A comprehensive review about the pathogenesis of this disease is important because of the necessity to update the results reported over the past years. Here, we present an updated review through Pubmed about the mammalian target of rapamycin (MTOR) pathway in FCD type 2. A wide variety of aspects was covered in 44 articles related to molecular and cellular biology, including experiments in animal and human models. The first publications appeared in 2004, but there is still a lack of studies specifically for one type of FCD. With the advancement of techniques and greater access to molecular and cellular experiments, such as induced pluripotent stem cells (iPSCs) and organoids, it is believed that the trend is increasing the number of publications contributing to the achievement of new discoveries.
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40
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Singh DK, Ling EA, Kaur C. Hypoxia and myelination deficits in the developing brain. Int J Dev Neurosci 2018; 70:3-11. [PMID: 29964158 DOI: 10.1016/j.ijdevneu.2018.06.012] [Citation(s) in RCA: 15] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/19/2018] [Revised: 05/28/2018] [Accepted: 06/26/2018] [Indexed: 12/15/2022] Open
Abstract
Myelination is a complex and orderly process during brain development that is essential for normal motor, cognitive and sensory functions. Cellular and molecular interactions between myelin-forming oligodendrocytes and axons are required for normal myelination in the developing brain. Oligodendrocyte progenitor cells (OPCs) proliferate and differentiate into mature myelin-forming oligodendrocytes. In this connection, astrocytes and microglia are also involved in survival and proliferation of OPCs. Hypoxic insults during the perinatal period affect the normal development, differentiation and maturation of the OPCs or cause their death resulting in impaired myelination. Several factors such as augmented release of proinflammatory cytokines by activated microglia and astrocytes, extracellular accumulation of excess glutamate and increased levels of nitric oxide are some of the underlying factors for hypoxia induced damage to the OPCs. Additionally, hypoxia also leads to down-regulation of several genes involved in oligodendrocyte differentiation encoding proteolipid protein, platelet-derived growth factor receptor and myelin-associated glycoprotein in the developing brain. Furthermore, oligodendrocytes may also accumulate increased amounts of iron in hypoxic conditions that triggers endoplasmic reticulum stress, misfolding of proteins and generation of reactive oxygen species that ultimately would lead to myelination deficits. More in-depth studies to elucidate the pathophysiological mechanisms underlying the inability of oligodendrocytes to myelinate the developing brain in hypoxic insults are desirable to develop new therapeutic options or strategies for myelination deficits.
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Affiliation(s)
- Dhiraj Kumar Singh
- Department of Anatomy, Yong Loo Lin School of Medicine, MD10, 4 Medical drive, National University of Singapore, 117597, Singapore
| | - Eng-Ang Ling
- Department of Anatomy, Yong Loo Lin School of Medicine, MD10, 4 Medical drive, National University of Singapore, 117597, Singapore
| | - Charanjit Kaur
- Department of Anatomy, Yong Loo Lin School of Medicine, MD10, 4 Medical drive, National University of Singapore, 117597, Singapore.
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41
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Wu S, Zeng Y, Lerner A, Gao B, Law M. Nervous System Injury and Neuroimaging of Zika Virus Infection. Front Neurol 2018; 9:227. [PMID: 29740383 PMCID: PMC5926540 DOI: 10.3389/fneur.2018.00227] [Citation(s) in RCA: 12] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/14/2018] [Accepted: 03/23/2018] [Indexed: 01/12/2023] Open
Abstract
In 2016, World Health Organization announced Zika virus infection and its neurological sequalae are a public health emergency of global scope. Preliminary studies have confirmed a relationship between Zika virus infection and certain neurological disorders, including microcephaly and Guillain–Barre syndrome (GBS). The neuroimaging features of microcephaly secondary to Zika virus infection include calcifications at the junction of gray–white matter and subcortical white matter with associated cortical abnormalities, diminution of white matter, large ventricles with or without hydrocephalus, cortical malformations, hypoplasia of cerebellum and brainstem, and enlargement of cerebellomedullary cistern. Contrast enhancement of the cauda equine nerve roots is the typical neuroimaging finding of GBS associated with Zika virus. This review describes the nervous system disorders and associated imaging findings seen in Zika virus infection, with the aim to improve the understanding of this disease. Imaging plays a key role on accurate diagnosis and prognostic evaluation of this disease.
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Affiliation(s)
- Shanshan Wu
- Department of Radiology, Affiliated Hospital of Guizhou Medical University, Guiyang, China.,Department of Radiology, Yantai Yuhuangding Hospital, Yantai, China
| | - Yu Zeng
- Department of Radiology, Affiliated Hospital of Guizhou Medical University, Guiyang, China
| | - Alexander Lerner
- Department of Radiology, Keck School of Medicine, University of Southern California, Los Angeles, CA, United States
| | - Bo Gao
- Department of Radiology, Yantai Yuhuangding Hospital, Yantai, China
| | - Meng Law
- Department of Radiology, Keck School of Medicine, University of Southern California, Los Angeles, CA, United States
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42
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Curatolo P, Moavero R, van Scheppingen J, Aronica E. mTOR dysregulation and tuberous sclerosis-related epilepsy. Expert Rev Neurother 2018; 18:185-201. [DOI: 10.1080/14737175.2018.1428562] [Citation(s) in RCA: 42] [Impact Index Per Article: 7.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/24/2022]
Affiliation(s)
- Paolo Curatolo
- Child Neurology and Psychiatry Unit, Systems Medicine Department, Tor Vergata University Hospital, Rome, Italy
| | - Romina Moavero
- Child Neurology and Psychiatry Unit, Systems Medicine Department, Tor Vergata University Hospital, Rome, Italy
- Child Neurology Unit, Neuroscience and Neurorehabilitation Department, “Bambino Gesù” Children’s Hospital, IRCCS, Rome, Italy
| | - Jackelien van Scheppingen
- Department of (Neuro)Pathology, Academic Medical Center, University of Amsterdam, Amsterdam, The Netherlands
| | - Eleonora Aronica
- Department of (Neuro)Pathology, Academic Medical Center, University of Amsterdam, Amsterdam, The Netherlands
- Stichting Epilepsie Instellingen Nederland (SEIN), The Netherlands
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43
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Deleo F, Thom M, Concha L, Bernasconi A, Bernhardt BC, Bernasconi N. Histological and MRI markers of white matter damage in focal epilepsy. Epilepsy Res 2017; 140:29-38. [PMID: 29227798 DOI: 10.1016/j.eplepsyres.2017.11.010] [Citation(s) in RCA: 40] [Impact Index Per Article: 5.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/29/2017] [Revised: 11/10/2017] [Accepted: 11/20/2017] [Indexed: 12/21/2022]
Abstract
Growing evidence highlights the importance of white matter in the pathogenesis of focal epilepsy. Ex vivo and post-mortem studies show pathological changes in epileptic patients in white matter myelination, axonal integrity, and cellular composition. Diffusion-weighted MRI and its analytical extensions, particularly diffusion tensor imaging (DTI), have been the most widely used technique to image the white matter in vivo for the last two decades, and have shown microstructural alterations in multiple tracts both in the vicinity and at distance from the epileptogenic focus. These techniques have also shown promising ability to predict cognitive status and response to pharmacological or surgical treatments. More recently, the hypothesis that focal epilepsy may be more adequately described as a system-level disorder has motivated a shift towards the study of macroscale brain connectivity. This review will cover emerging findings contributing to our understanding of white matter alterations in focal epilepsy, studied by means of histological and ultrastructural analyses, diffusion MRI, and large-scale network analysis. Focus is put on temporal lobe epilepsy and focal cortical dysplasia. This topic was addressed in a special interest group on neuroimaging at the 70th annual meeting of the American Epilepsy Society, held in Houston December 2-6, 2016.
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Affiliation(s)
- Francesco Deleo
- NeuroImaging of Epilepsy Laboratory, Montreal Neurological Institute, McGill University, Canada
| | - Maria Thom
- Division of Neuropathology and Department of Clinical and Experimental Epilepsy, UCL Institute of Neurology, Queen Square, London WC1N 3BG, UK
| | - Luis Concha
- Instituto de Neurobiología, Universidad Nacional Autónoma de México, Querétaro, Mexico
| | - Andrea Bernasconi
- NeuroImaging of Epilepsy Laboratory, Montreal Neurological Institute, McGill University, Canada
| | - Boris C Bernhardt
- NeuroImaging of Epilepsy Laboratory, Montreal Neurological Institute, McGill University, Canada; Multimodal Imaging and Connectome Analysis Laboratory, Montreal Neurological Institute, McGill University, Canada
| | - Neda Bernasconi
- NeuroImaging of Epilepsy Laboratory, Montreal Neurological Institute, McGill University, Canada.
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44
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Thom M, Liu J, Bongaarts A, Reinten RJ, Paradiso B, Jäger HR, Reeves C, Somani A, An S, Marsdon D, McEvoy A, Miserocchi A, Thorne L, Newman F, Bucur S, Honavar M, Jacques T, Aronica E. Multinodular and vacuolating neuronal tumors in epilepsy: dysplasia or neoplasia? Brain Pathol 2017; 28:155-171. [PMID: 28833756 PMCID: PMC5887881 DOI: 10.1111/bpa.12555] [Citation(s) in RCA: 38] [Impact Index Per Article: 5.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/10/2017] [Revised: 06/27/2017] [Accepted: 08/01/2017] [Indexed: 12/28/2022] Open
Abstract
Multinodular and vacuolating neuronal tumor (MVNT) is a new pattern of neuronal tumour included in the recently revised WHO 2016 classification of tumors of the CNS. There are 15 reports in the literature to date. They are typically associated with late onset epilepsy and a neoplastic vs. malformative biology has been questioned. We present a series of ten cases and compare their pathological and genetic features to better characterized epilepsy‐associated malformations including focal cortical dysplasia type II (FCDII) and low‐grade epilepsy‐associated tumors (LEAT). Clinical and neuroradiology data were reviewed and a broad immunohistochemistry panel was applied to explore neuronal and glial differentiation, interneuronal populations, mTOR pathway activation and neurodegenerative changes. Next generation sequencing was performed for targeted multi‐gene analysis to identify mutations common to epilepsy lesions including FCDII and LEAT. All of the surgical cases in this series presented with seizures, and were located in the temporal lobe. There was a lack of any progressive changes on serial pre‐operative MRI and a mean age at surgery of 45 years. The vacuolated cells of the lesion expressed mature neuronal markers (neurofilament/SMI32, MAP2, synaptophysin). Prominent labelling of the lesional cells for developmentally regulated proteins (OTX1, TBR1, SOX2, MAP1b, CD34, GFAPδ) and oligodendroglial lineage markers (OLIG2, SMI94) was observed. No mutations were detected in the mTOR pathway genes, BRAF, FGFR1 or MYB. Clinical, pathological and genetic data could indicate that MVNT aligns more with a malformative lesion than a true neoplasm with origin from a progenitor neuro‐glial cell type showing aberrant maturation.
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Affiliation(s)
- Maria Thom
- Departments of Clinical and Experimental Epilepsy and Neuropathology, UCL Institute of Neurology and the National Hospital for Neurology and Neurosurgery, Queen Square, London WCN1BG, UK
| | - Joan Liu
- Departments of Clinical and Experimental Epilepsy and Neuropathology, UCL Institute of Neurology and the National Hospital for Neurology and Neurosurgery, Queen Square, London WCN1BG, UK
| | - Anika Bongaarts
- Department of (Neuro)Pathology, Academic Medical Center, Amsterdam, The Netherlands
| | - Roy J Reinten
- Department of (Neuro)Pathology, Academic Medical Center, Amsterdam, The Netherlands
| | - Beatrice Paradiso
- Departments of Clinical and Experimental Epilepsy and Neuropathology, UCL Institute of Neurology and the National Hospital for Neurology and Neurosurgery, Queen Square, London WCN1BG, UK.,Cardiovascular Pathology Unit, Department of Cardiac, Thoracic and Vascular Sciences University of Padua Medical School, Padova, Italy
| | - Hans Rolf Jäger
- Neuroradiological Academic Unit, Department of Brain Repair and Rehabilitation, UCL Institute of Neurology, Queen Square, London WC1N 3BG, UK
| | - Cheryl Reeves
- Departments of Clinical and Experimental Epilepsy and Neuropathology, UCL Institute of Neurology and the National Hospital for Neurology and Neurosurgery, Queen Square, London WCN1BG, UK
| | - Alyma Somani
- Departments of Clinical and Experimental Epilepsy and Neuropathology, UCL Institute of Neurology and the National Hospital for Neurology and Neurosurgery, Queen Square, London WCN1BG, UK
| | - Shu An
- Departments of Clinical and Experimental Epilepsy and Neuropathology, UCL Institute of Neurology and the National Hospital for Neurology and Neurosurgery, Queen Square, London WCN1BG, UK
| | - Derek Marsdon
- Departments of Clinical and Experimental Epilepsy and Neuropathology, UCL Institute of Neurology and the National Hospital for Neurology and Neurosurgery, Queen Square, London WCN1BG, UK
| | - Andrew McEvoy
- Victor Horsley Department of Neurosurgery, National Hospital for Neurology and Neurosurgery, Queen Square, London WC1N 3BG, UK
| | - Anna Miserocchi
- Victor Horsley Department of Neurosurgery, National Hospital for Neurology and Neurosurgery, Queen Square, London WC1N 3BG, UK
| | - Lewis Thorne
- Victor Horsley Department of Neurosurgery, National Hospital for Neurology and Neurosurgery, Queen Square, London WC1N 3BG, UK
| | - Fay Newman
- Neurosurgery Department, Brighton and Sussex University Hospitals, Brighton, UK
| | - Sorin Bucur
- Neurosurgery Department, Brighton and Sussex University Hospitals, Brighton, UK
| | - Mrinalini Honavar
- Department of Anatomic Pathology, Hospital Pedro Hispano, Matosinhos, Portugal
| | - Tom Jacques
- Neuropathology Department, Great Ormond Street Hospital, London, UK
| | - Eleonora Aronica
- Department of (Neuro)Pathology, Academic Medical Center, Amsterdam, The Netherlands.,Stichting Epilepsie Instellingen Nederland (SEIN), Heemstede, The Netherlands
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Chi X, Huang C, Li R, Wang W, Wu M, Li J, Zhou D. Inhibition of mTOR Pathway by Rapamycin Decreases P-glycoprotein Expression and Spontaneous Seizures in Pharmacoresistant Epilepsy. J Mol Neurosci 2017; 61:553-562. [PMID: 28229367 DOI: 10.1007/s12031-017-0897-x] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/04/2016] [Accepted: 02/08/2017] [Indexed: 02/05/2023]
Abstract
The mammalian target of rapamycin (mTOR) has been demonstrated to mediate multidrug resistance in various tumors by inducing P-glycoprotein (P-gp) overexpression. Here, we investigated the correlation between the mTOR pathway and P-gp expression in pharmacoresistant epilepsy. Temporal cortex specimens were obtained from patients with refractory mesial temporal lobe epilepsy (mTLE) and age-matched controls who underwent surgeries at West China Hospital of Sichuan University between June 2014 and May 2015. We established a rat model of epilepsy kindled by coriaria lactone (CL) and screened pharmacoresistant rats (non-responders) using phenytoin. Non-responders were treated for 4 weeks with vehicle only or with the mTOR pathway inhibitor rapamycin at doses of 1, 3, and 6 mg/kg. Western blotting and immunohistochemistry were used to detect the expression of phospho-S6 (P-S6) and P-gp at different time points (1 h, 8 h, 1 day, 3 days, 1 weeks, 2 weeks, and 4 weeks) after the onset of treatment. Overexpression of P-S6 and P-gp was detected in both refractory mTLE patients and non-responder rats. Rapamycin showed an inhibitory effect on P-S6 and P-gp expression 1 week after treatment in rats. In addition, the expression levels of P-S6 and P-gp in the 6 mg/kg group were significantly lower than those in the 1 mg/kg or the 3 mg/kg group at the same time points (all P < 0.05). Moreover, rapamycin decreased the duration and number of CL-induced seizures, as well as the stage of non-responders (all P < 0.05). The current study indicates that the mTOR signaling pathway plays a critical role in P-gp expression in drug-resistant epilepsy. Inhibition of the mTOR pathway by rapamycin may be a potential therapeutic approach for pharmacoresistant epilepsy.
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Affiliation(s)
- Xiaosa Chi
- Department of Neurology, West China Hospital, Sichuan University, 37th Guoxuexiang Road, Chengdu, Sichuan Province, 610041, China
| | - Cheng Huang
- Department of Neurology, West China Hospital, Sichuan University, 37th Guoxuexiang Road, Chengdu, Sichuan Province, 610041, China
| | - Rui Li
- Key Lab of Transplant Engineering and Immunology, MOH, West China Hospital, Sichuan University, Chengdu, Sichuan Province, China
| | - Wei Wang
- Department of Neurology, West China Hospital, Sichuan University, 37th Guoxuexiang Road, Chengdu, Sichuan Province, 610041, China
| | - Mengqian Wu
- Department of Neurology, West China Hospital, Sichuan University, 37th Guoxuexiang Road, Chengdu, Sichuan Province, 610041, China
| | - Jinmei Li
- Department of Neurology, West China Hospital, Sichuan University, 37th Guoxuexiang Road, Chengdu, Sichuan Province, 610041, China
| | - Dong Zhou
- Department of Neurology, West China Hospital, Sichuan University, 37th Guoxuexiang Road, Chengdu, Sichuan Province, 610041, China.
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46
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Qin L, Liu X, Liu S, Liu Y, Yang Y, Yang H, Chen Y, Chen L. Differentially expressed proteins underlying childhood cortical dysplasia with epilepsy identified by iTRAQ proteomic profiling. PLoS One 2017; 12:e0172214. [PMID: 28222113 PMCID: PMC5319751 DOI: 10.1371/journal.pone.0172214] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/07/2016] [Accepted: 02/01/2017] [Indexed: 02/06/2023] Open
Abstract
Cortical dysplasia accounts for at least 14% of epilepsy cases, and is mostly seen in children. However, the understanding of molecular mechanisms and pathogenesis underlying cortical dysplasia is limited. The aim of this cross-sectional study is to identify potential key molecules in the mechanisms of cortical dysplasia by screening the proteins expressed in brain tissues of childhood cortical dysplasia patients with epilepsy using isobaric tags for relative and absolute quantitation-based tandem mass spectrometry compared to controls, and several differentially expressed proteins that are not reported to be associated with cortical dysplasia previously were selected for validation using real-time polymerase chain reaction, immunoblotting and immunohistochemistry. 153 out of 3340 proteins were identified differentially expressed between childhood cortical dysplasia patients and controls. And FSCN1, CRMP1, NDRG1, DPYSL5, MAP4, and FABP3 were selected for validation and identified to be increased in childhood cortical dysplasia patients, while PRDX6 and PSAP were identified decreased. This is the first report on differentially expressed proteins in childhood cortical dysplasia. We identified differential expression of FSCN1, CRMP1, NDRG1, DPYSL5, MAP4, FABP3, PRDX6 and PSAP in childhood cortical dysplasia patients, these proteins are involved in various processes and have various function. These results may provide new directions or targets for the research of childhood cortical dysplasia, and may be helpful in revealing molecular mechanisms and pathogenesis and/or pathophysiology of childhood cortical dysplasia if further investigated.
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Affiliation(s)
- Lu Qin
- Department of Neurology, The Second Affiliated Hospital of Chongqing Medical University, Chongqing, People’s Republic of China
| | - Xi Liu
- Department of Neurology, The Second Affiliated Hospital of Chongqing Medical University, Chongqing, People’s Republic of China
| | - Shiyong Liu
- Department of Neurosurgery, The Xinqiao Hospital of Third Military Medical University, Chongqing, People’s Republic of China
| | - Yi Liu
- Department of Neurology, The Second Affiliated Hospital of Chongqing Medical University, Chongqing, People’s Republic of China
| | - Yixuan Yang
- Department of Infectious Disease, The Second Affiliated Hospital of Chongqing Medical University, Chongqing, People’s Republic of China
| | - Hui Yang
- Department of Neurosurgery, The Xinqiao Hospital of Third Military Medical University, Chongqing, People’s Republic of China
| | - Yangmei Chen
- Department of Neurology, The Second Affiliated Hospital of Chongqing Medical University, Chongqing, People’s Republic of China
| | - Lifen Chen
- Department of Neurology, The Second Affiliated Hospital of Chongqing Medical University, Chongqing, People’s Republic of China
- * E-mail:
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47
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Ercan E, Han JM, Di Nardo A, Winden K, Han MJ, Hoyo L, Saffari A, Leask A, Geschwind DH, Sahin M. Neuronal CTGF/CCN2 negatively regulates myelination in a mouse model of tuberous sclerosis complex. J Exp Med 2017; 214:681-697. [PMID: 28183733 PMCID: PMC5339668 DOI: 10.1084/jem.20160446] [Citation(s) in RCA: 72] [Impact Index Per Article: 10.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/29/2016] [Revised: 11/09/2016] [Accepted: 12/30/2016] [Indexed: 12/11/2022] Open
Abstract
Disruption of myelination during development has been implicated in a range of neurodevelopmental disorders including tuberous sclerosis complex (TSC). TSC patients with autism display impairments in white matter integrity. Similarly, mice lacking neuronal Tsc1 have a hypomyelination phenotype. However, the mechanisms that underlie these phenotypes remain unknown. In this study, we demonstrate that neuronal TSC1/2 orchestrates a program of oligodendrocyte maturation through the regulated secretion of connective tissue growth factor (CTGF). We characterize oligodendrocyte maturation both in vitro and in vivo. We find that neuron-specific Tsc1 deletion results in an increase in CTGF secretion that non-cell autonomously stunts oligodendrocyte development and decreases the total number of oligodendrocytes. Genetic deletion of CTGF from neurons, in turn, mitigates the TSC-dependent hypomyelination phenotype. These results show that the mechanistic target of rapamycin (mTOR) pathway in neurons regulates CTGF production and secretion, revealing a paracrine mechanism by which neuronal signaling regulates oligodendrocyte maturation and myelination in TSC. This study highlights the role of mTOR-dependent signaling between neuronal and nonneuronal cells in the regulation of myelin and identifies an additional therapeutic avenue for this disease.
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Affiliation(s)
- Ebru Ercan
- Department of Neurology, F.M. Kirby Center for Neurobiology, Boston Children's Hospital, Harvard Medical School, Boston, MA 02115
| | - Juliette M Han
- Department of Neurology, F.M. Kirby Center for Neurobiology, Boston Children's Hospital, Harvard Medical School, Boston, MA 02115
| | - Alessia Di Nardo
- Department of Neurology, F.M. Kirby Center for Neurobiology, Boston Children's Hospital, Harvard Medical School, Boston, MA 02115
| | - Kellen Winden
- Department of Neurology, F.M. Kirby Center for Neurobiology, Boston Children's Hospital, Harvard Medical School, Boston, MA 02115
| | - Min-Joon Han
- Department of Neurology, F.M. Kirby Center for Neurobiology, Boston Children's Hospital, Harvard Medical School, Boston, MA 02115.,Translational Neuroscience Center, Boston Children's Hospital, Harvard Medical School, Boston, MA 02115
| | - Leonie Hoyo
- Department of Neurology, F.M. Kirby Center for Neurobiology, Boston Children's Hospital, Harvard Medical School, Boston, MA 02115.,Translational Neuroscience Center, Boston Children's Hospital, Harvard Medical School, Boston, MA 02115
| | - Afshin Saffari
- Department of Neurology, F.M. Kirby Center for Neurobiology, Boston Children's Hospital, Harvard Medical School, Boston, MA 02115
| | - Andrew Leask
- Department of Dentistry, Schulich School of Medicine and Dentistry, London, Ontario N6A 5C1, Canada.,Department of Physiology and Pharmacology, Schulich School of Medicine and Dentistry, London, Ontario N6A 5C1, Canada
| | - Daniel H Geschwind
- Department of Neurology, University of California, Los Angeles School of Medicine, Los Angeles, CA 90095.,Semel Institute, University of California, Los Angeles School of Medicine, Los Angeles, CA 90095.,Department of Human Genetics, University of California, Los Angeles School of Medicine, Los Angeles, CA 90095
| | - Mustafa Sahin
- Department of Neurology, F.M. Kirby Center for Neurobiology, Boston Children's Hospital, Harvard Medical School, Boston, MA 02115 .,Translational Neuroscience Center, Boston Children's Hospital, Harvard Medical School, Boston, MA 02115
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