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Avşar PA, Akçay E, Gürkaş E. Psychotic attack during the clinical course of megalencephalic leukoencephalopathy with subcortical cysts: a case report. Eur Child Adolesc Psychiatry 2024:10.1007/s00787-024-02539-y. [PMID: 39039223 DOI: 10.1007/s00787-024-02539-y] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 10/09/2023] [Accepted: 07/16/2024] [Indexed: 07/24/2024]
Abstract
OBJECTIVES Van der Knaap disease or megalencephalic leukoencephalopathy with subcortical cysts (MLC), is a slowly progressive neurodegenerative disease with macrocephaly. We present a case of MLC with a confirmed homozygous MLC1 mutation who presented with a psychotic attack at a very young age. CASE PRESENTATION An 11-year-old girl was admitted to the emergency room with delusions, hallucinations, and irritability. She was diagnosed with MLC at 18 months old. Her psychotic symptoms were improved with the administration of risperidone treatment added to her valproic acid treatment for EEG abnormality. CONCLUSION In this case study we reported the first episode of a psychotic attack during the clinical course of MLC. This case indicates the possibility that MLC influences the onset of the psychotic attack. Further investigation with more patients is needed to identify the relationship.
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Affiliation(s)
- Pınar Aydoğan Avşar
- Department of Child and Adolescent Psychiatry, Alanya Education and Training Hospital, Antalya, Turkey.
| | - Elif Akçay
- Department of Child and Adolescent Psychiatry, Ankara Bilkent City Hospital, Ankara, Turkey
| | - Esra Gürkaş
- Department of Pediatric Neurology, Ankara Bilkent City Hospital, Ankara, Turkey
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Kaur N, Arora K, Radhakrishnan P, Narayanan DL, Shukla A. Intragenic homozygous duplication in HEPACAM is associated with megalencephalic leukoencephalopathy with subcortical cysts type 2A. Neurogenetics 2024; 25:85-91. [PMID: 38280046 DOI: 10.1007/s10048-024-00743-1] [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: 10/16/2023] [Accepted: 01/05/2024] [Indexed: 01/29/2024]
Abstract
Disease-causing variants in HEPACAM are associated with megalencephalic leukoencephalopathy with subcortical cysts 2A (MLC2A, MIM# 613,925, autosomal recessive), and megalencephalic leukoencephalopathy with subcortical cysts 2B, remitting, with or without impaired intellectual development (MLC2B, MIM# 613,926, autosomal dominant). These disorders are characterised by macrocephaly, seizures, motor delay, cognitive impairment, ataxia, and spasticity. Brain magnetic resonance imaging (MRI) in these individuals shows swollen cerebral hemispheric white matter and subcortical cysts, mainly in the frontal and temporal regions. To date, 45 individuals from 39 families are reported with biallelic and heterozygous variants in HEPACAM, causing MLC2A and MLC2B, respectively. A 9-year-old male presented with developmental delay, gait abnormalities, seizures, macrocephaly, dysarthria, spasticity, and hyperreflexia. MRI revealed subcortical cysts with diffuse cerebral white matter involvement. Whole-exome sequencing (WES) in the proband did not reveal any clinically relevant single nucleotide variants. However, copy number variation analysis from the WES data of the proband revealed a copy number of 4 for exons 3 and 4 of HEPACAM. Validation and segregation were done by quantitative PCR which confirmed the homozygous duplication of these exons in the proband and carrier status in both parents. To the best of our knowledge, this is the first report of an intragenic duplication in HEPACAM causing MLC2A.
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Affiliation(s)
- Namanpreet Kaur
- Department of Medical Genetics, Kasturba Medical College, Manipal, Manipal Academy of Higher Education, Manipal, India
| | - Khyati Arora
- Department of Medical Genetics, Kasturba Medical College, Manipal, Manipal Academy of Higher Education, Manipal, India
| | - Periyasamy Radhakrishnan
- Department of Medical Genetics, Kasturba Medical College, Manipal, Manipal Academy of Higher Education, Manipal, India
| | - Dhanya Lakshmi Narayanan
- Department of Medical Genetics, Kasturba Medical College, Manipal, Manipal Academy of Higher Education, Manipal, India
- DBT-Wellcome Trust India Alliance Early Career Clinical and Public Health Research Fellow, Hyderabad, India
| | - Anju Shukla
- Department of Medical Genetics, Kasturba Medical College, Manipal, Manipal Academy of Higher Education, Manipal, India.
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Passchier EMJ, Bisseling Q, Helman G, van Spaendonk RML, Simons C, Olsthoorn RCL, van der Veen H, Abbink TEM, van der Knaap MS, Min R. Megalencephalic leukoencephalopathy with subcortical cysts: a variant update and review of the literature. Front Genet 2024; 15:1352947. [PMID: 38487253 PMCID: PMC10938252 DOI: 10.3389/fgene.2024.1352947] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/09/2023] [Accepted: 01/29/2024] [Indexed: 03/17/2024] Open
Abstract
The leukodystrophy megalencephalic leukoencephalopathy with subcortical cysts (MLC) is characterized by infantile-onset macrocephaly and chronic edema of the brain white matter. With delayed onset, patients typically experience motor problems, epilepsy and slow cognitive decline. No treatment is available. Classic MLC is caused by bi-allelic recessive pathogenic variants in MLC1 or GLIALCAM (also called HEPACAM). Heterozygous dominant pathogenic variants in GLIALCAM lead to remitting MLC, where patients show a similar phenotype in early life, followed by normalization of white matter edema and no clinical regression. Rare patients with heterozygous dominant variants in GPRC5B and classic MLC were recently described. In addition, two siblings with bi-allelic recessive variants in AQP4 and remitting MLC have been identified. The last systematic overview of variants linked to MLC dates back to 2006. We provide an updated overview of published and novel variants. We report on genetic variants from 508 patients with MLC as confirmed by MRI diagnosis (258 from our database and 250 extracted from 64 published reports). We describe 151 unique MLC1 variants, 29 GLIALCAM variants, 2 GPRC5B variants and 1 AQP4 variant observed in these MLC patients. We include experiments confirming pathogenicity for some variants, discuss particularly notable variants, and provide an overview of recent scientific and clinical insight in the pathophysiology of MLC.
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Affiliation(s)
- Emma M. J. Passchier
- Department of Child Neurology, Amsterdam Leukodystrophy Center, Emma Children’s Hospital, Amsterdam University Medical Center, Amsterdam Neuroscience, Amsterdam, Netherlands
- Department of Integrative Neurophysiology, Center for Neurogenomics and Cognitive Research, Vrije Universiteit Amsterdam, Amsterdam Neuroscience, Amsterdam, Netherlands
| | - Quinty Bisseling
- Department of Child Neurology, Amsterdam Leukodystrophy Center, Emma Children’s Hospital, Amsterdam University Medical Center, Amsterdam Neuroscience, Amsterdam, Netherlands
- Department of Integrative Neurophysiology, Center for Neurogenomics and Cognitive Research, Vrije Universiteit Amsterdam, Amsterdam Neuroscience, Amsterdam, Netherlands
| | - Guy Helman
- Translational Bioinformatics, Murdoch Children’s Research Institute, The Royal Children’s Hospital, Parkville, VIC, Australia
| | | | - Cas Simons
- Translational Bioinformatics, Murdoch Children’s Research Institute, The Royal Children’s Hospital, Parkville, VIC, Australia
- Centre for Population Genomics, Garvan Institute of Medical Research, Sydney, NSW, Australia
| | | | - Hieke van der Veen
- Department of Child Neurology, Amsterdam Leukodystrophy Center, Emma Children’s Hospital, Amsterdam University Medical Center, Amsterdam Neuroscience, Amsterdam, Netherlands
- Department of Complex Trait Genetics, Center for Neurogenomics and Cognitive Research, Vrije Universiteit Amsterdam, Amsterdam Neuroscience, Amsterdam, Netherlands
| | - Truus E. M. Abbink
- Department of Child Neurology, Amsterdam Leukodystrophy Center, Emma Children’s Hospital, Amsterdam University Medical Center, Amsterdam Neuroscience, Amsterdam, Netherlands
| | - Marjo S. van der Knaap
- Department of Child Neurology, Amsterdam Leukodystrophy Center, Emma Children’s Hospital, Amsterdam University Medical Center, Amsterdam Neuroscience, Amsterdam, Netherlands
- Department of Integrative Neurophysiology, Center for Neurogenomics and Cognitive Research, Vrije Universiteit Amsterdam, Amsterdam Neuroscience, Amsterdam, Netherlands
| | - Rogier Min
- Department of Child Neurology, Amsterdam Leukodystrophy Center, Emma Children’s Hospital, Amsterdam University Medical Center, Amsterdam Neuroscience, Amsterdam, Netherlands
- Department of Integrative Neurophysiology, Center for Neurogenomics and Cognitive Research, Vrije Universiteit Amsterdam, Amsterdam Neuroscience, Amsterdam, Netherlands
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Zha J, Chen Y, Cao F, Xu Y, Yang Z, Wen S, Liang M, Wu H, Zhong J. Homozygous variant of MLC1 results in megalencephalic leukoencephalopathy with subcortical cysts. Mol Genet Genomic Med 2024; 12:e2394. [PMID: 38337154 PMCID: PMC10858299 DOI: 10.1002/mgg3.2394] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/18/2023] [Revised: 01/18/2024] [Accepted: 01/24/2024] [Indexed: 02/12/2024] Open
Abstract
BACKGROUND Megalencephalic leukoencephalopathy with subcortical cysts (MLC) is a rare, inherited disorder that causes epilepsy, intellectual disorders, and early onset macrocephaly. MLC1 has been identified as a main pathogenic gene. METHODS Clinical data such as magnetic resonance imaging (MRI), routine blood tests, and physical examinations were collected from proband. Trio whole-exome sequencing (WES) of the family was performed, and all variants with a minor allele frequency (<0.01) in the exon and canonical splicing sites were selected for further pathogenic evaluation. Candidate variants were validated using Sanger sequencing. RESULTS Here, we report a new homozygous variant identified in two children from the same family in the MLC1 gene [NM_015166.4: c.838_843delinsATTTTA, (p.Ser280_Phe281delinsIleLeu)]. This variant is classified as variant of uncertain significance (VUS) according to the ACMG guidelines. Further experiments demonstrate that the newly identified variant causes a decrease of MLC1 protein levels when expressed in a heterologous expression system. CONCLUSION Our case expands on this genetic variation and provides new evidence for the clinical diagnosis of MLC1-related MLC.
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Affiliation(s)
- Jian Zha
- Department of NeurologyJiangxi Provincial Children's HospitalNanchangJiangxiChina
| | - Yong Chen
- Department of NeurologyJiangxi Provincial Children's HospitalNanchangJiangxiChina
| | - Fangfang Cao
- Department of NeurologyJiangxi Provincial Children's HospitalNanchangJiangxiChina
| | - Yuxin Xu
- Department of NeurologyJiangxi Provincial Children's HospitalNanchangJiangxiChina
| | | | | | | | - Huaping Wu
- Department of NeurologyJiangxi Provincial Children's HospitalNanchangJiangxiChina
| | - Jianmin Zhong
- Department of NeurologyJiangxi Provincial Children's HospitalNanchangJiangxiChina
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Kim HG, Han D, Kim J, Choi JS, Cho KO. 3D MR fingerprinting-derived myelin water fraction characterizing brain development and leukodystrophy. J Transl Med 2023; 21:914. [PMID: 38102606 PMCID: PMC10725020 DOI: 10.1186/s12967-023-04788-y] [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: 09/15/2023] [Accepted: 12/06/2023] [Indexed: 12/17/2023] Open
Abstract
BACKGROUND Magnetic resonance fingerprinting (MRF) enables fast myelin quantification via the myelin water fraction (MWF), offering a noninvasive method to assess brain development and disease. However, MRF-derived MWF lacks histological evaluation and remains unexamined in relation to leukodystrophy. This study aimed to access MRF-derived MWF through histology in mice and establish links between myelin, development, and leukodystrophy in mice and children, demonstrating its potential applicability in animal and human studies. METHODS 3D MRF was performed on normal C57BL/6 mice with different ages, megalencephalic leukoencephalopathy with subcortical cyst 1 wild type (MLC1 WT, control) mice, and MLC 1 knock-out (MLC1 KO, leukodystrophy) mice using a 3 T MRI. MWF values were analyzed from 3D MRF data, and histological myelin quantification was carried out using immunohistochemistry to anti-proteolipid protein (PLP) in the corpus callosum and cortex. The associations between 'MWF and PLP' and 'MWF and age' were evaluated in C57BL/6 mice. MWF values were compared between MLC1 WT and MLC1 KO mice. MWF of normal developing children were retrospectively collected and the association between MWF and age was assessed. RESULTS In 35 C57BL/6 mice (age range; 3 weeks-48 weeks), MWF showed positive relations with PLP immunoreactivity in the corpus callosum (β = 0.0006, P = 0.04) and cortex (β = 0.0005, P = 0.006). In 12-week-old C57BL/6 mice MWF showed positive relations with PLP immunoreactivity (β = 0.0009, P = 0.003, R2 = 0.54). MWF in the corpus callosum (β = 0.0022, P < 0.001) and cortex (β = 0.0010, P < 0.001) showed positive relations with age. Seven MLC1 WT and 9 MLC1 KO mice showed different MWF values in the corpus callous (P < 0.001) and cortex (P < 0.001). A total of 81 children (median age, 126 months; range, 0-199 months) were evaluated and their MWF values according to age showed the best fit for the third-order regression model (adjusted R2 range, 0.44-0.94, P < 0.001). CONCLUSION MWF demonstrated associations with histologic myelin quantity, age, and the presence of leukodystrophy, underscoring the potential of 3D MRF-derived MWF as a rapid and noninvasive quantitative indicator of brain myelin content in both mice and humans.
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Affiliation(s)
- Hyun Gi Kim
- Department of Radiology, Eunpyeong St. Mary's Hospital, College of Medicine, The Catholic University of Korea, Seoul, Korea
| | | | - Jimin Kim
- Department of Radiology, Eunpyeong St. Mary's Hospital, College of Medicine, The Catholic University of Korea, Seoul, Korea
| | - Jeong-Sun Choi
- Department of Pharmacology, Department of Biomedicine & Health Sciences, Catholic Neuroscience Institute, Institute for Aging and Metabolic Diseases, College of Medicine, The Catholic University of Korea, 222 Banpo-daero, Seocho-Gu, Seoul, 06591, South Korea
| | - Kyung-Ok Cho
- Department of Pharmacology, Department of Biomedicine & Health Sciences, Catholic Neuroscience Institute, Institute for Aging and Metabolic Diseases, College of Medicine, The Catholic University of Korea, 222 Banpo-daero, Seocho-Gu, Seoul, 06591, South Korea.
- CMC Institute for Basic Medical Science, The Catholic Medical Center of The Catholic University of Korea, Seoul, Korea.
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Chen X, Qu H, Yao Q, Cai X, He T, Zhang X. Case report: Analysis of a gene variant and prenatal diagnosis in a family with megalencephalic leukoencephalopathy with subcortical cysts. Front Neurol 2023; 14:1253398. [PMID: 37928140 PMCID: PMC10622957 DOI: 10.3389/fneur.2023.1253398] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/05/2023] [Accepted: 09/18/2023] [Indexed: 11/07/2023] Open
Abstract
Megalencephalic leukoencephalopathy with subcortical cysts (MLC) is a rare inherited cerebral white matter disorder in children. Pathogenic variations in the causative gene MLC1 are found in approximately 76% of patients and are inherited in an autosomal recessive manner. In this study, we identified an IVS2 + 1delG variant in MLC1 in the firstborn girl of a pregnant woman who has the clinical features of MLC, including macrocephaly, motor development delay, progressive functional deterioration, and myelinopathy, whereas no obvious subcortical cysts were observed by magnetic resonance imaging of the brain. The proband is homozygous for the IVS2 + 1delG mutation, which was inherited from the parents. This variant disrupts the donor splice site, causing an abnormal transcript that results in a premature termination codon and produces a truncated protein, which was confirmed to affect splicing by MLC1 cDNA analysis. This variant was also detected in family members, and a prenatal diagnosis for the fetus was undertaken. Eventually, the couple gave birth to an unaffected baby. Furthermore, we conducted a long-term follow-up of the proband's clinical course. This report improves our understanding of the genetic and phenotypic characteristics of MLC and provides a new genetic basis for prenatal diagnosis and genetic counseling.
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Affiliation(s)
- Xi Chen
- Department of Medical Genetics and Prenatal Diagnosis Center, West China Second University Hospital, Sichuan University, Chengdu, China
- Department of Obstetrics and Gynecology, West China Second University Hospital, Sichuan University, Chengdu, China
- Key Laboratory of Birth Defects and Related Diseases of Women and Children (Sichuan University), Ministry of Education, Chengdu, China
| | - Haibo Qu
- Key Laboratory of Birth Defects and Related Diseases of Women and Children (Sichuan University), Ministry of Education, Chengdu, China
- Department of Radiology, West China Second University Hospital, Sichuan University, Chengdu, China
| | - Qiang Yao
- Department of Obstetrics and Gynecology, West China Second University Hospital, Sichuan University, Chengdu, China
- Key Laboratory of Birth Defects and Related Diseases of Women and Children (Sichuan University), Ministry of Education, Chengdu, China
| | - Xiaotang Cai
- Key Laboratory of Birth Defects and Related Diseases of Women and Children (Sichuan University), Ministry of Education, Chengdu, China
- Department of Rehabilitation, West China Second University Hospital, Sichuan University, Chengdu, China
| | - Tiantian He
- Department of Medical Genetics and Prenatal Diagnosis Center, West China Second University Hospital, Sichuan University, Chengdu, China
- Department of Obstetrics and Gynecology, West China Second University Hospital, Sichuan University, Chengdu, China
- Key Laboratory of Birth Defects and Related Diseases of Women and Children (Sichuan University), Ministry of Education, Chengdu, China
| | - Xuemei Zhang
- Department of Medical Genetics and Prenatal Diagnosis Center, West China Second University Hospital, Sichuan University, Chengdu, China
- Department of Obstetrics and Gynecology, West China Second University Hospital, Sichuan University, Chengdu, China
- Key Laboratory of Birth Defects and Related Diseases of Women and Children (Sichuan University), Ministry of Education, Chengdu, China
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Nowacki JC, Fields AM, Fu MM. Emerging cellular themes in leukodystrophies. Front Cell Dev Biol 2022; 10:902261. [PMID: 36003149 PMCID: PMC9393611 DOI: 10.3389/fcell.2022.902261] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/22/2022] [Accepted: 06/30/2022] [Indexed: 11/18/2022] Open
Abstract
Leukodystrophies are a broad spectrum of neurological disorders that are characterized primarily by deficiencies in myelin formation. Clinical manifestations of leukodystrophies usually appear during childhood and common symptoms include lack of motor coordination, difficulty with or loss of ambulation, issues with vision and/or hearing, cognitive decline, regression in speech skills, and even seizures. Many cases of leukodystrophy can be attributed to genetic mutations, but they have diverse inheritance patterns (e.g., autosomal recessive, autosomal dominant, or X-linked) and some arise from de novo mutations. In this review, we provide an updated overview of 35 types of leukodystrophies and focus on cellular mechanisms that may underlie these disorders. We find common themes in specialized functions in oligodendrocytes, which are specialized producers of membranes and myelin lipids. These mechanisms include myelin protein defects, lipid processing and peroxisome dysfunction, transcriptional and translational dysregulation, disruptions in cytoskeletal organization, and cell junction defects. In addition, non-cell-autonomous factors in astrocytes and microglia, such as autoimmune reactivity, and intercellular communication, may also play a role in leukodystrophy onset. We hope that highlighting these themes in cellular dysfunction in leukodystrophies may yield conceptual insights on future therapeutic approaches.
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Khalaf-Nazzal R, Dweikat I, Maree M, Alawneh M, Barahmeh M, Doulani RT, Qrareya M, Qadi M, Dudin A. Prevalent MLC1 mutation causing autosomal recessive megalencephalic leukoencephalopathy in consanguineous Palestinian families. Brain Dev 2022; 44:454-461. [PMID: 35440380 DOI: 10.1016/j.braindev.2022.03.009] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 12/28/2021] [Revised: 03/24/2022] [Accepted: 03/29/2022] [Indexed: 10/18/2022]
Abstract
BACKGROUND Recessive forms of megalencephalic leukoencephalopathy with subcortical cysts (MLC, OMIM 604004) is a rare early-onset leukodystrophy that presents with macrocephaly, seizures, slowly progressive gross motor deterioration, and MRI evidence of diffuse symmetric white matter swelling and subcortical cysts in the anterior temporal and frontoparietal regions. Later in the disease course, significant spasticity and ataxia develop, which may be accompanied by intellectual deterioration. This disease is caused mostly by biallelic pathogenic variants in the MLC1 gene. METHODS In this study, we analysed the clinical and molecular architecture of 6 individuals, belonging to 4 unrelated consanguineous Palestinian families, presenting with consistent MLC features. We sequenced the entire coding and flanking intronic regions of the MLC1 gene. RESULTS In all recruited individuals, we detected one recurrent homozygous splice donor mutation NM_015166.4: c.423 + 1G > A. All parents were heterozygous carriers. The mutation abolishes a highly conserved splice site in humans and other species. In silico splice predictors suggested the loss of a canonical splice donor site (CADD score 33.0. SpliceAI: 0.980). The c.423 + 1G > A variant is rare; it was detected in only 4 heterozygous carriers in gnomAD. CONCLUSION In this study, we identified a recurrent MLC1 variant (c.423 + 1G > A) as the cause of MLC among a group of Palestinian patients originating from a particular region of the country. Cost-effective studies should be performed to evaluate the implementation of carrier screening in adults originating from this region. Our findings have the potential to contribute to improved genetic diagnosis and carrier testing for individuals within this population and the wider community.
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Affiliation(s)
- Reham Khalaf-Nazzal
- Faculty of Medicine, Arab American University of Palestine, Jenin, Palestine.
| | - Imad Dweikat
- Faculty of Medicine, Arab American University of Palestine, Jenin, Palestine
| | - Mosab Maree
- Medicine Department, Faculty of Medicine and Health Sciences, An-Najah National University, and An-Najah National University Hospital, Nablus, Palestine
| | - Maysa Alawneh
- Medicine Department, Faculty of Medicine and Health Sciences, An-Najah National University, and An-Najah National University Hospital, Nablus, Palestine
| | - Myassar Barahmeh
- Biomedical Sciences Department, Faculty of Medicine and Health Sciences, An-Najah National University, Nablus, Palestine
| | - Rasha T Doulani
- Clinical Sciences Department, Faculty of Medicine and Health Sciences, An-Najah National University, Nablus, Palestine
| | - Mohammad Qrareya
- Clinical Sciences Department, Faculty of Medicine and Health Sciences, An-Najah National University, Nablus, Palestine
| | - Mohammad Qadi
- Biomedical Sciences Department, Faculty of Medicine and Health Sciences, An-Najah National University, Nablus, Palestine
| | - Anwar Dudin
- Pediatric Neurology Outpatient Clinic, Ramallah, Palestine
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Kong F, Zheng H, Liu X, Lin S, Wang J, Guo Z. Association Between Late-Onset Leukoencephalopathy With Vanishing White Matter and Compound Heterozygous EIF2B5 Gene Mutations: A Case Report and Review of the Literature. Front Neurol 2022; 13:813032. [PMID: 35785335 PMCID: PMC9243765 DOI: 10.3389/fneur.2022.813032] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/11/2021] [Accepted: 05/11/2022] [Indexed: 11/16/2022] Open
Abstract
Leukoencephalopathy with vanishing white matter (LVWM) is an autosomal recessive disease. Ovarioleukodystrophy is defined as LVWM in females showing signs or symptoms of gradual ovarian failure. We present a 38-year-old female with ovarioleukodystrophy who showed status epilepticus, gait instability, slurred speech, abdominal tendon hyperreflexia, and ovarian failure. Abnormal EEG, characteristic magnetic resonance, and unreported EIF2B5 compound heterozygous mutations [c.1016G>A (p.R339Q) and c.1157G>A (p.G386D)] were found. Furthermore, the present report summarizes 20 female patients with adult-onset ovarioleukodystrophy and EIF2B5 gene mutations. In conclusion, a new genetic locus for LVWM was discovered. Compared with previous cases, mutations at different EIF2B5 sites might have different clinical manifestations and obvious clinical heterogeneity.
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Affiliation(s)
- Fanxin Kong
- Encephalopathy and Psychology Department, Shenzhen Traditional Chinese Medicine Hospital, Shenzhen, China
- The Fourth Clinical Medical College of Guangzhou University of Chinese Medicine, Shenzhen, China
- *Correspondence: Fanxin Kong
| | - Haotao Zheng
- Encephalopathy and Psychology Department, Shenzhen Traditional Chinese Medicine Hospital, Shenzhen, China
- The Fourth Clinical Medical College of Guangzhou University of Chinese Medicine, Shenzhen, China
| | - Xuan Liu
- Encephalopathy and Psychology Department, Shenzhen Traditional Chinese Medicine Hospital, Shenzhen, China
- The Fourth Clinical Medical College of Guangzhou University of Chinese Medicine, Shenzhen, China
| | - Songjun Lin
- Encephalopathy and Psychology Department, Shenzhen Traditional Chinese Medicine Hospital, Shenzhen, China
- The Fourth Clinical Medical College of Guangzhou University of Chinese Medicine, Shenzhen, China
| | - Jianjun Wang
- Encephalopathy and Psychology Department, Shenzhen Traditional Chinese Medicine Hospital, Shenzhen, China
- The Fourth Clinical Medical College of Guangzhou University of Chinese Medicine, Shenzhen, China
- Jianjun Wang
| | - Zhouke Guo
- The Fourth Clinical Medical College of Guangzhou University of Chinese Medicine, Shenzhen, China
- Shenzhen Traditional Chinese Medicine Hospital, Shenzhen, China
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Sadek AA, Aladawy MA, Mansour TMM, Ibrahim MF, Mohamed MM, Gad EF, Othman AA, Ahmed HA, Kasim AK, Wagdy WM, Hasan MHT, Abdelkreem E. Clinicoradiologic Correlation in 22 Egyptian Children With Megalencephalic Leukoencephalopathy With Subcortical Cysts. J Child Neurol 2022; 37:380-389. [PMID: 35322718 DOI: 10.1177/08830738221078683] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 02/05/2023]
Abstract
Megalencephalic leukoencephalopathy with subcortical cysts (MLC) is a rare genetic form of cerebral white matter disease whose clinicoradiologic correlation has not been completely understood. In this study, we investigated the association between clinical and brain magnetic resonance imaging (MRI) features in 22 Egyptian children (median age 7 years) with MLC. Gross motor function was assessed using the Gross Motor Function Classification System, and evaluation of brain MRI followed a consistent scoring system. Each parameter of extensive cerebral white matter T2 hyperintensity, moderate-to-severe wide ventricle/enlarged subarachnoid space, and greater than 2 temporal subcortical cysts was significantly associated (P < .05) with worse Gross Motor Function Classification System score, language abnormality, and ataxia. Having >2 parietal subcortical cysts was significantly related to a worse Gross Motor Function Classification System score (P = .04). The current study indicates that patients with MLC manifest signification association between certain brain MRI abnormalities and neurologic features, but this should be confirmed in larger studies.
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Affiliation(s)
- Abdelrahim A Sadek
- Neuropsychiatry Unit, Department of Pediatrics, 68890Faculty of Medicine, Sohag University, Sohag, Egypt
| | - Mohammed A Aladawy
- Neurology Unit, Department of Pediatrics, Faculty of Medicine, 195495Al-Azhar University, Assiut, Egypt
| | - Tarek M M Mansour
- Department of Radio-diagnosis, Faculty of Medicine, 68820Al-Azhar University, Assiut, Egypt
| | - Mohamed F Ibrahim
- Neurology Unit, Department of Pediatrics, Faculty of Medicine, 195495Al-Azhar University, Assiut, Egypt
| | - Montaser M Mohamed
- Department of Pediatrics, 68890Faculty of Medicine, Sohag University, Sohag, Egypt
| | - Eman F Gad
- Department of Pediatrics, Faculty of Medicine, Assiut University, Assiut, Egypt
| | - Amr A Othman
- Neuropsychiatry Unit, Department of Pediatrics, 68890Faculty of Medicine, Sohag University, Sohag, Egypt
| | - Hosny A Ahmed
- Neurology Unit, Department of Pediatrics, Faculty of Medicine, 195495Al-Azhar University, Assiut, Egypt
| | - Abdin K Kasim
- Department of Neurosurgery, 68890Faculty of Medicine, Sohag University, Sohag, Egypt
| | - Wael M Wagdy
- Department of Radio-diagnosis, 113328Faculty of Medicine, South Valley University, Qena, Egypt
| | - Mohamed H T Hasan
- Department of Radio-diagnosis, Faculty of Medicine, 68820Al-Azhar University, Cairo, Egypt
| | - Elsayed Abdelkreem
- Department of Pediatrics, 68890Faculty of Medicine, Sohag University, Sohag, Egypt
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Bugiani M, Plug BC, Man JHK, Breur M, van der Knaap MS. Heterogeneity of white matter astrocytes in the human brain. Acta Neuropathol 2022; 143:159-177. [PMID: 34878591 DOI: 10.1007/s00401-021-02391-3] [Citation(s) in RCA: 15] [Impact Index Per Article: 7.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/27/2021] [Revised: 11/17/2021] [Accepted: 11/28/2021] [Indexed: 12/12/2022]
Abstract
Astrocytes regulate central nervous system development, maintain its homeostasis and orchestrate repair upon injury. Emerging evidence support functional specialization of astroglia, both between and within brain regions. Different subtypes of gray matter astrocytes have been identified, yet molecular and functional diversity of white matter astrocytes remains largely unexplored. Nonetheless, their important and diverse roles in maintaining white matter integrity and function are well recognized. Compelling evidence indicate that impairment of normal astrocytic function and their response to injury contribute to a wide variety of diseases, including white matter disorders. In this review, we highlight our current understanding of astrocyte heterogeneity in the white matter of the mammalian brain and how an interplay between developmental origins and local environmental cues contribute to astroglial diversification. In addition, we discuss whether, and if so, how, heterogeneous astrocytes could contribute to white matter function in health and disease and focus on the sparse human research data available. We highlight four leukodystrophies primarily due to astrocytic dysfunction, the so-called astrocytopathies. Insight into the role of astroglial heterogeneity in both healthy and diseased white matter may provide new avenues for therapies aimed at promoting repair and restoring normal white matter function.
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12
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Hwang J, Park K, Lee GY, Yoon BY, Kim H, Roh SH, Lee BC, Kim K, Lim HH. Transmembrane topology and oligomeric nature of an astrocytic membrane protein, MLC1. Open Biol 2021; 11:210103. [PMID: 34847774 PMCID: PMC8633789 DOI: 10.1098/rsob.210103] [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] [Indexed: 01/07/2023] Open
Abstract
MLC1 is a membrane protein mainly expressed in astrocytes, and genetic mutations lead to the development of a leukodystrophy, megalencephalic leukoencephalopathy with subcortical cysts disease. Currently, the biochemical properties of the MLC1 protein are largely unknown. In this study, we aimed to characterize the transmembrane (TM) topology and oligomeric nature of the MLC1 protein. Systematic immunofluorescence staining data revealed that the MLC1 protein has eight TM domains and that both the N- and C-terminus face the cytoplasm. We found that MLC1 can be purified as an oligomer and could form a trimeric complex in both detergent micelles and reconstituted proteoliposomes. Additionally, a single-molecule photobleaching experiment showed that MLC1 protein complexes could consist of three MLC1 monomers in the reconstituted proteoliposomes. These results can provide a basis for both the high-resolution structural determination and functional characterization of the MLC1 protein.
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Affiliation(s)
- Junmo Hwang
- Neurovascular Unit Research Group, Korea Brain Research Institute (KBRI), 61 Cheomdan-ro, Dong-gu, Daegu 41068, Republic of Korea
| | - Kunwoong Park
- Neurovascular Unit Research Group, Korea Brain Research Institute (KBRI), 61 Cheomdan-ro, Dong-gu, Daegu 41068, Republic of Korea
| | - Ga-Young Lee
- Brain Research Core Facility, Korea Brain Research Institute (KBRI), Daegu, Republic of Korea
| | - Bo Young Yoon
- Neurovascular Unit Research Group, Korea Brain Research Institute (KBRI), 61 Cheomdan-ro, Dong-gu, Daegu 41068, Republic of Korea
| | - Hyunmin Kim
- School of Biological Science, Institute of Molecular Biology and Genetics, Seoul National University, Seoul, Republic of Korea
| | - Sung Hoon Roh
- School of Biological Science, Institute of Molecular Biology and Genetics, Seoul National University, Seoul, Republic of Korea
| | - Byoung-Cheol Lee
- Neurovascular Unit Research Group, Korea Brain Research Institute (KBRI), 61 Cheomdan-ro, Dong-gu, Daegu 41068, Republic of Korea
| | - Kipom Kim
- Brain Research Core Facility, Korea Brain Research Institute (KBRI), Daegu, Republic of Korea
| | - Hyun-Ho Lim
- Neurovascular Unit Research Group, Korea Brain Research Institute (KBRI), 61 Cheomdan-ro, Dong-gu, Daegu 41068, Republic of Korea,Department of Brain and Cognitive Sciences, Daegu Gyeongbuk Institute of Science and Technology (DGIST), Daegu, Republic of Korea
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13
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M P S, Varghese L, Thomas RS, Prasad SG. Siblings with megalencephalic leukoencephalopathy with subcortical cysts van der Knaap disease. BJR Case Rep 2021; 7:20200150. [PMID: 35136617 PMCID: PMC8803242 DOI: 10.1259/bjrcr.20200150] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/03/2020] [Revised: 05/08/2021] [Accepted: 05/25/2021] [Indexed: 11/17/2022] Open
Abstract
Cerebral leukoencephalopathy and megalencephaly with subcortical cysts (also
known as van der Knaap disease) is an autosomal recessive condition. The disease
was initially described in India and Netherlands independently and seems to have
highest incidence in Indian Agrawal community and Turkish population.1 The objective of this study is
to document the case of two siblings with this condition, from a non-Agrawal
Indian community and briefly describe the imaging features of this condition.
Two siblings, born out of a third-degree consanguineous marriage, with simple
focal seizures were subjected to MRI with diffusion-weighted imaging and
spectrometry. The findings were compared to diseases with similar clinical
presentation. Subcortical cysts initially involving anterior temporal lobes and
subsequently frontal and parietal lobes, sparing of central white mater, small N
acetyl aspartate peak and diffusion facilitation were the imaging findings. The
imaging findings were consistent with the diagnosis of the rare genetic
disorder- Cerebral leukoencephalopathy and megalencephaly with subcortical
cysts.
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Affiliation(s)
- Saanida M P
- Department of Radiology, Government Medical College, Kozhikode, Kerala, India
| | - Lin Varghese
- Department of Radiology, Government Medical College, Kozhikode, Kerala, India
| | - Rinu Susan Thomas
- Department of Radiology, Government Medical College, Kozhikode, Kerala, India
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14
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Randhawa HS, Randhawa J, Kulkarni A, More A, Jain A. A Very Rare Case of Megalencephalic Leukoencephalopathy With Subcortical Cysts in a Child Born of Non-Consanguineous Marriage in a Non-Predisposed Community. Cureus 2021; 13:e16941. [PMID: 34381660 PMCID: PMC8351400 DOI: 10.7759/cureus.16941] [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] [Accepted: 08/06/2021] [Indexed: 11/05/2022] Open
Abstract
Megalencephalic leukoencephalopathy (MLC) with subcortical cysts is a very rare white matter disorder characterized predominantly by motor developmental delay and seizures in a child with macrocephaly. Extrapyramidal symptoms, ataxia and mental retardation may also occur. Only a few cases of the disease have been reported worldwide with most of them showing an autosomal recessive pattern of inheritance. In India, most cases have been reported in Agrawal community. Here, we present an interesting case of MLC in a child born in non-Agrawal community to a non-consanguineous marriage. By reporting this case we intend to increase the research horizon and increase the published literature for atypical cases of MLC.
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Affiliation(s)
| | - Jasneet Randhawa
- Department of Resident Medical Services, Fortis Escorts Hospital, Amritsar, IND
| | - Anagha Kulkarni
- Department of Pediatrics, Lokmanya Tilak Municipal General (LTMG) Hospital, Mumbai, IND
| | - Akshay More
- Department of Interventional Radiology, Lokmanya Tilak Municipal General (LTMG) Hospital, Mumbai, IND
| | - Akshay Jain
- Department of Radiology, Government Medical College, Kolhapur, IND
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15
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Chandrasekar S, John J, Satapathy AK, Mahapatro S. When the head is big, think this too: Megalencephalic leukoencephalopathy in a toddler with only a large head. A case report. J Family Med Prim Care 2021; 10:2416-2418. [PMID: 34322448 PMCID: PMC8284232 DOI: 10.4103/jfmpc.jfmpc_2012_20] [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: 09/29/2020] [Revised: 12/02/2020] [Accepted: 12/02/2020] [Indexed: 11/19/2022] Open
Abstract
We present a one-year old, developmentally normal toddler from a non Agarwal community, who presented to us with only a large head. The examination findings were unremarkable except a large head circumference. Neuroimaging confirmed the diagnosis of megalencephalic leukoencephalopathy (MLC). Although developmental delay and seizures are common manifestations in MLC, we want to highlight the fact that many children like ours may have no neurological manifestations at all which makes it necessary to do neuroimaging to establish the diagnosis and offer genetic testing for confirmation of the same.
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Affiliation(s)
- Shyam Chandrasekar
- Department of Pediatrics, All India Institute of Medical Sciences, Bhubaneswar, Odisha, India
| | - Joseph John
- Department of Pediatrics, All India Institute of Medical Sciences, Bhubaneswar, Odisha, India
| | - Amit K Satapathy
- Department of Pediatrics, All India Institute of Medical Sciences, Bhubaneswar, Odisha, India
| | - Samarendra Mahapatro
- Department of Pediatrics, All India Institute of Medical Sciences, Bhubaneswar, Odisha, India
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16
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Ulloa-Navas MJ, Pérez-Borredá P, Morales-Gallel R, Saurí-Tamarit A, García-Tárraga P, Gutiérrez-Martín AJ, Herranz-Pérez V, García-Verdugo JM. Ultrastructural Characterization of Human Oligodendrocytes and Their Progenitor Cells by Pre-embedding Immunogold. Front Neuroanat 2021; 15:696376. [PMID: 34248510 PMCID: PMC8262677 DOI: 10.3389/fnana.2021.696376] [Citation(s) in RCA: 7] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/16/2021] [Accepted: 06/02/2021] [Indexed: 11/13/2022] Open
Abstract
Oligodendrocytes are the myelinating cells of the central nervous system. They provide trophic, metabolic, and structural support to neurons. In several pathologies such as multiple sclerosis (MS), these cells are severely affected and fail to remyelinate, thereby leading to neuronal death. The gold standard for studying remyelination is the g-ratio, which is measured by means of transmission electron microscopy (TEM). Therefore, studying the fine structure of the oligodendrocyte population in the human brain at different stages through TEM is a key feature in this field of study. Here we study the ultrastructure of oligodendrocytes, its progenitors, and myelin in 10 samples of human white matter using nine different markers of the oligodendrocyte lineage (NG2, PDGFRα, A2B5, Sox10, Olig2, BCAS1, APC-(CC1), MAG, and MBP). Our findings show that human oligodendrocytes constitute a very heterogeneous population within the human white matter and that its stages of differentiation present characteristic features that can be used to identify them by TEM. This study sheds light on how these cells interact with other cells within the human brain and clarify their fine characteristics from other glial cell types.
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Affiliation(s)
- María J Ulloa-Navas
- Laboratory of Compared Neurobiology, University of Valencia-CIBERNED, Paterna, Spain
| | - Pedro Pérez-Borredá
- Laboratory of Compared Neurobiology, University of Valencia-CIBERNED, Paterna, Spain.,Neurosurgery Department, Consorcio Hospital General Universitario de Valencia, Valencia, Spain
| | - Raquel Morales-Gallel
- Laboratory of Compared Neurobiology, University of Valencia-CIBERNED, Paterna, Spain
| | - Ana Saurí-Tamarit
- Laboratory of Compared Neurobiology, University of Valencia-CIBERNED, Paterna, Spain
| | | | | | - Vicente Herranz-Pérez
- Laboratory of Compared Neurobiology, University of Valencia-CIBERNED, Paterna, Spain.,Predepartmental Unit of Medicine, Faculty of Health Sciences, Universitat Jaume I, Castelló de la Plana, Spain
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17
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von Jonquieres G, Rae CD, Housley GD. Emerging Concepts in Vector Development for Glial Gene Therapy: Implications for Leukodystrophies. Front Cell Neurosci 2021; 15:661857. [PMID: 34239416 PMCID: PMC8258421 DOI: 10.3389/fncel.2021.661857] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/31/2021] [Accepted: 05/12/2021] [Indexed: 12/12/2022] Open
Abstract
Central Nervous System (CNS) homeostasis and function rely on intercellular synchronization of metabolic pathways. Developmental and neurochemical imbalances arising from mutations are frequently associated with devastating and often intractable neurological dysfunction. In the absence of pharmacological treatment options, but with knowledge of the genetic cause underlying the pathophysiology, gene therapy holds promise for disease control. Consideration of leukodystrophies provide a case in point; we review cell type – specific expression pattern of the disease – causing genes and reflect on genetic and cellular treatment approaches including ex vivo hematopoietic stem cell gene therapies and in vivo approaches using adeno-associated virus (AAV) vectors. We link recent advances in vectorology to glial targeting directed towards gene therapies for specific leukodystrophies and related developmental or neurometabolic disorders affecting the CNS white matter and frame strategies for therapy development in future.
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Affiliation(s)
- Georg von Jonquieres
- Translational Neuroscience Facility, Department of Physiology, School of Medical Sciences, UNSW Sydney, Sydney, NSW, Australia
| | - Caroline D Rae
- Neuroscience Research Australia, Randwick, NSW, Australia
| | - Gary D Housley
- Translational Neuroscience Facility, Department of Physiology, School of Medical Sciences, UNSW Sydney, Sydney, NSW, Australia
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18
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Biswas A, Malhotra M, Mankad K, Carney O, D'Arco F, Muthusamy K, Sudhakar SV. Clinico-radiological phenotyping and diagnostic pathways in childhood neurometabolic disorders-a practical introductory guide. Transl Pediatr 2021; 10:1201-1230. [PMID: 34012862 PMCID: PMC8107844 DOI: 10.21037/tp-20-335] [Citation(s) in RCA: 12] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 12/15/2022] Open
Abstract
Inborn errors of metabolism (IEM) although individually rare, together constitute a significant proportion of childhood neurological disorders. Majority of these disorders occur due to deficiency of an enzyme in a specific metabolic pathway, leading to damage by accumulation of a toxic substrate or deficiency of an essential metabolite. Early diagnosis is crucial in many of these conditions to prevent or minimise brain damage. Whilst many of the neuroimaging features are nonspecific, certain disorders demonstrate specific patterns due to selective vulnerability of different structures to different insults. Along with clinical and biochemical profile, neuroimaging thus plays a pivotal role in differentiating metabolic disorders from other causes, in providing a differential diagnosis or suggesting a metabolic pathway derangement, and on occasion also helps make a specific diagnosis. This allows initiation of targeted metabolic and genetic work up and treatment. Familiarity with the clinical features, relevant biochemical features and neuroimaging findings of common metabolic disorders to facilitate a prompt diagnosis cannot thus be overemphasized. In this article, we describe the latest classification scheme, the clinical and biochemical clues and common radiological patterns. The diagnostic algorithm followed in daily practice after clinico-radiological phenotyping is alluded to and illustrated by clinical vignettes. Focused sections on neonatal metabolic disorders and mitochondrial disorders are also provided. The purpose of this article is to provide a brief overview and serve as a practical primer to clinical and radiological phenotypes and diagnostic aspects of IEM.
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Affiliation(s)
- Asthik Biswas
- Department of Diagnostic Imaging, The Hospital for Sick Children, Toronto, Ontario, Canada.,Department of Medical Imaging, University of Toronto, Toronto, Ontario, Canada
| | - Mukul Malhotra
- Department of Neurology, Christian Medical College, Vellore, India
| | - Kshitij Mankad
- Neuroradiology Unit, Great Ormond Street Hospital NHS Foundation Trust, London, UK
| | - Olivia Carney
- Neuroradiology Unit, Great Ormond Street Hospital NHS Foundation Trust, London, UK
| | - Felice D'Arco
- Neuroradiology Unit, Great Ormond Street Hospital NHS Foundation Trust, London, UK
| | | | - Sniya Valsa Sudhakar
- Neuroradiology Unit, Great Ormond Street Hospital NHS Foundation Trust, London, UK
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19
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Bosch A, Estévez R. Megalencephalic Leukoencephalopathy: Insights Into Pathophysiology and Perspectives for Therapy. Front Cell Neurosci 2021; 14:627887. [PMID: 33551753 PMCID: PMC7862579 DOI: 10.3389/fncel.2020.627887] [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: 11/10/2020] [Accepted: 12/30/2020] [Indexed: 01/13/2023] Open
Abstract
Megalencephalic leukoencephalopathy with subcortical cysts (MLC) is a rare genetic disorder belonging to the group of vacuolating leukodystrophies. It is characterized by megalencephaly, loss of motor functions, epilepsy, and mild mental decline. In brain biopsies of MLC patients, vacuoles were observed in myelin and in astrocytes surrounding blood vessels. It is mainly caused by recessive mutations in MLC1 and HEPACAM (also called GLIALCAM) genes. These disease variants are called MLC1 and MLC2A with both types of patients sharing the same clinical phenotype. Besides, dominant mutations in HEPACAM were also identified in a subtype of MLC patients (MLC2B) with a remitting phenotype. MLC1 and GlialCAM proteins form a complex mainly expressed in brain astrocytes at the gliovascular interface and in Bergmann glia at the cerebellum. Both proteins regulate several ion channels and transporters involved in the control of ion and water fluxes in glial cells, either directly influencing their location and function, or indirectly regulating associated signal transduction pathways. However, the MLC1/GLIALCAM complex function and the related pathological mechanisms leading to MLC are still unknown. It has been hypothesized that, in MLC, the role of glial cells in brain ion homeostasis is altered in both physiological and inflammatory conditions. There is no therapy for MLC patients, only supportive treatment. As MLC2B patients show an MLC reversible phenotype, we speculated that the phenotype of MLC1 and MLC2A patients could also be mitigated by the re-introduction of the correct gene even at later stages. To prove this hypothesis, we injected in the cerebellar subarachnoid space of Mlc1 knockout mice an adeno-associated virus (AAV) coding for human MLC1 under the control of the glial-fibrillary acidic protein promoter. MLC1 expression in the cerebellum extremely reduced myelin vacuolation at all ages in a dose-dependent manner. This study could be considered as the first preclinical approach for MLC. We also suggest other potential therapeutic strategies in this review.
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Affiliation(s)
- Assumpció Bosch
- Department of Biochemistry and Molecular Biology, Institute of Neurosciences, Univ. Autònoma de Barcelona, Barcelona, Spain.,Unitat Mixta UAB-VHIR, Vall d'Hebron Institut de Recerca (VHIR), Barcelona, Spain.,Centro de Investigación Biomédica en Red sobre Enfermedades Neurodegenerativas (CIBERNED), Instituto de Salud Carlos III, Madrid, Spain
| | - Raúl Estévez
- Departament de Ciències Fisiològiques, IDIBELL-Institute of Neurosciences, Universitat de Barcelona, Barcelona, Spain.,Centro de Investigación Biomédica en Red sobre Enfermedades Raras (CIBERER), Instituto de Salud Carlos III, Madrid, Spain
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20
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Sánchez A, García-Lareu B, Puig M, Prat E, Ruberte J, Chillón M, Nunes V, Estévez R, Bosch A. Cerebellar Astrocyte Transduction as Gene Therapy for Megalencephalic Leukoencephalopathy. Neurotherapeutics 2020; 17:2041-2053. [PMID: 32372403 PMCID: PMC7851290 DOI: 10.1007/s13311-020-00865-y] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/22/2023] Open
Abstract
Megalencephalic leukoencephalopathy with subcortical cysts (MLC) is a rare genetic disorder belonging to the group of vacuolating leukodystrophies. It is characterized by megalencephaly, loss of motor functions, epilepsy, and mild mental decline. In brain biopsies of MLC patients, vacuoles were observed in myelin and in astrocytes surrounding blood vessels. There is no therapy for MLC patients, only supportive treatment. We show here a preclinical gene therapy approach for MLC using the Mlc1 knock-out mouse. An adeno-associated virus coding for human MLC1 under the control of the glial fibrillary acidic protein promoter was injected in the cerebellar subarachnoid space of Mlc1 knock-out and wild-type animals at 2 months of age, before the onset of the disease, as a preventive approach. We also tested a therapeutic strategy by injecting the animals at 5 months, once the histopathological abnormalities are starting, or at 15 months, when they have progressed to a more severe pathology. MLC1 expression in the cerebellum restored the adhesion molecule GlialCAM and the chloride channel ClC-2 localization in Bergmann glia, which both are mislocalized in Mlc1 knock-out model. More importantly, myelin vacuolation was extremely reduced in treated mice at all ages and correlated with the amount of expressed MLC1 in Bergmann glia, indicating not only the preventive potential of this strategy but also its therapeutic capacity. In summary, here we provide the first therapeutic approach for patients affected with MLC. This work may have also implications to treat other diseases affecting motor function such as ataxias.
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Affiliation(s)
- Angela Sánchez
- Department of Biochemistry and Molecular Biology and Institute of Neurosciences, Edifici H, Universitat Autònoma de Barcelona, E-08193, Bellaterra, Spain
- Unitat Mixta UAB-VHIR, Vall d'Hebron Institut de Recerca (VHIR), Barcelona, Spain
| | - Belén García-Lareu
- Department of Biochemistry and Molecular Biology and Institute of Neurosciences, Edifici H, Universitat Autònoma de Barcelona, E-08193, Bellaterra, Spain
| | - Meritxell Puig
- Department of Biochemistry and Molecular Biology and Institute of Neurosciences, Edifici H, Universitat Autònoma de Barcelona, E-08193, Bellaterra, Spain
- Unitat Mixta UAB-VHIR, Vall d'Hebron Institut de Recerca (VHIR), Barcelona, Spain
| | - Esther Prat
- Laboratori de Genètica Molecular, Programa de Genes, Malaltia i Teràpia, IDIBELL, L'Hospitalet de Llobregat, Barcelona, Spain
- Unitat de Genètica, Departament de Ciències Fisiològiques, Facultad de Medicina i Ciències de la Salut, Univ. de Barcelona, L'Hospitalet de Llobregat, Barcelona, Spain
- Centro de Investigación Biomédica en Red sobre Enfermedades Raras (CIBERER), Instituto de Salud Carlos III, Madrid, Spain
| | - Jesús Ruberte
- Department of Animal Health and Anatomy and Center of Animal Biotechnology and Gene Therapy (CBATEG), Univ. Autònoma de Barcelona, Barcelona, Spain
| | - Miguel Chillón
- Department of Biochemistry and Molecular Biology and Institute of Neurosciences, Edifici H, Universitat Autònoma de Barcelona, E-08193, Bellaterra, Spain
- Unitat Mixta UAB-VHIR, Vall d'Hebron Institut de Recerca (VHIR), Barcelona, Spain
- Institut Català de Recerca i Estudis Avançats (ICREA), Barcelona, Spain
| | - Virginia Nunes
- Laboratori de Genètica Molecular, Programa de Genes, Malaltia i Teràpia, IDIBELL, L'Hospitalet de Llobregat, Barcelona, Spain
- Unitat de Genètica, Departament de Ciències Fisiològiques, Facultad de Medicina i Ciències de la Salut, Univ. de Barcelona, L'Hospitalet de Llobregat, Barcelona, Spain
- Centro de Investigación Biomédica en Red sobre Enfermedades Raras (CIBERER), Instituto de Salud Carlos III, Madrid, Spain
| | - Raul Estévez
- Centro de Investigación Biomédica en Red sobre Enfermedades Raras (CIBERER), Instituto de Salud Carlos III, Madrid, Spain.
- Departament de Ciències Fisiològiques, IDIBELL - Institute of Neurosciences, Universitat de Barcelona, E-08907, Barcelona, Spain.
| | - Assumpció Bosch
- Department of Biochemistry and Molecular Biology and Institute of Neurosciences, Edifici H, Universitat Autònoma de Barcelona, E-08193, Bellaterra, Spain.
- Unitat Mixta UAB-VHIR, Vall d'Hebron Institut de Recerca (VHIR), Barcelona, Spain.
- Centro de Investigación Biomédica en Red sobre Enfermedades Neurodegenerativas (CIBERNED), Instituto de Salud Carlos III, Madrid, Spain.
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21
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Ishikawa M, Omachi Y, Sato N, Nakagawa E. Bipolar disorder in megalencephalic leukoencephalopathy with subcortical cysts: a case report. BMC Psychiatry 2020; 20:349. [PMID: 32620087 PMCID: PMC7333431 DOI: 10.1186/s12888-020-02750-6] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 04/13/2019] [Accepted: 06/23/2020] [Indexed: 11/20/2022] Open
Abstract
BACKGROUND Megalencephalic leukoencephalopathy with subcortical cysts (MLC), or Van der Knaap disease, is a rare spongiform leukodystrophy that is characterized by macrocephaly, progressive motor dysfunction, and mild mental retardation. It is very rare for mental illness such as psychotic disorders, affective disorders and anxiety disorders to occur in MLC. CASE PRESENTATION A 17-year-old boy was admitted to our hospital after he developed symptoms of depressive state with catatonia after being diagnosed as having MLC with confirmed MLC1 mutation. His catatonic symptoms were improved with administration of olanzapine and sertraline and he was discharged after 4 months. Several months later, he became hypomanic. He was diagnosed with bipolar II disorder. Mood swings were controlled with the administration of carbamazepine. CONCLUSIONS This case is the first report of bipolar disorder during the clinical course of MLC. This case indicate the possibility that MLC influences the development of bipolar disorder in MLC, however, further studies involving more patients are required to clarify this.
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Affiliation(s)
- Masanori Ishikawa
- Department of Social Welfare Service, Faculty of Human Sciences, Mejiro University, 4-31-1 Nakaochiai, Shinjuku-ku, Tokyo, 161-8539, Japan.
| | - Yoshie Omachi
- grid.419280.60000 0004 1763 8916Department of Psychiatry, National Center Hospital of Neurology and Psychiatry, National Center of Neurology and Psychiatry, Tokyo, 187-8551 Japan
| | - Noriko Sato
- grid.419280.60000 0004 1763 8916Department of Radiology, National Center Hospital of Neurology and Psychiatry, National Center of Neurology and Psychiatry, Tokyo, 187-8551 Japan
| | - Eiji Nakagawa
- grid.419280.60000 0004 1763 8916Department of Child Neurology, National Center Hospital of Neurology and Psychiatry, National Center of Neurology and Psychiatry, Tokyo, 187-8551 Japan
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22
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Ilyas M, Efthymiou S, Salpietro V, Noureen N, Zafar F, Rauf S, Mir A, Houlden H. Novel variants underlying autosomal recessive intellectual disability in Pakistani consanguineous families. BMC MEDICAL GENETICS 2020; 21:59. [PMID: 32209057 PMCID: PMC7092478 DOI: 10.1186/s12881-020-00998-z] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 11/11/2019] [Accepted: 03/16/2020] [Indexed: 12/24/2022]
Abstract
Background Intellectual disability (ID) is both a clinically diverse and genetically heterogeneous group of disorder, with an onset of cognitive impairment before the age of 18 years. ID is characterized by significant limitations in intellectual functioning and adaptive behaviour. The identification of genetic variants causing ID and neurodevelopmental disorders using whole-exome sequencing (WES) has proven to be successful. So far more than 1222 primary and 1127 candidate genes are associated with ID. Methods To determine pathogenic variants causative of ID in three unrelated consanguineous Pakistani families, we used a combination of WES, homozygosity-by-descent mapping, de-deoxy sequencing and bioinformatics analysis. Results Rare pathogenic single nucleotide variants identified by WES which passed our filtering strategy were confirmed by traditional Sanger sequencing and segregation analysis. Novel and deleterious variants in VPS53, GLB1, and MLC1, genes previously associated with variable neurodevelopmental anomalies, were found to segregate with the disease in the three families. Conclusions This study expands our knowledge on the molecular basis of ID as well as the clinical heterogeneity associated to different rare genetic causes of neurodevelopmental disorders. This genetic study could also provide additional knowledge to help genetic assessment as well as clinical and social management of ID in Pakistani families.
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Affiliation(s)
- Muhammad Ilyas
- Department of Biological Sciences, International Islamic University Islamabad, Islamabad, 44000, Pakistan
| | - Stephanie Efthymiou
- Department of Neuromuscular Disorders, UCL Institute of Neurology, Queen Square, London, WC1N 3BG, UK
| | - Vincenzo Salpietro
- Department of Neuromuscular Disorders, UCL Institute of Neurology, Queen Square, London, WC1N 3BG, UK
| | - Nuzhat Noureen
- Department of Pediatric Neurology, Children's Hospital and Institute of Child Health, Multan, 60000, Pakistan
| | - Faisal Zafar
- Department of Pediatric Neurology, Children's Hospital and Institute of Child Health, Multan, 60000, Pakistan
| | - Sobiah Rauf
- National Center for Bioinformatics, Quaid-i-Azam University, Islamabad, Pakistan
| | - Asif Mir
- Department of Biological Sciences, International Islamic University Islamabad, Islamabad, 44000, Pakistan.
| | - Henry Houlden
- Department of Neuromuscular Disorders, UCL Institute of Neurology, Queen Square, London, WC1N 3BG, UK
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A Novel Splice-site Mutation on the MLC1 Gene Leading to Exon 9 Skipping and Megalencephalic Leukoencephalopathy with Subcortical Cysts in a Turkish Patient. Balkan J Med Genet 2020; 22:89-92. [PMID: 31942423 PMCID: PMC6956632 DOI: 10.2478/bjmg-2019-0019] [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] [Indexed: 11/20/2022] Open
Abstract
Megalencephalic leukoencephalopathy (MLC) with subcortical cysts, also known as Van der Knaap disease (MIM #604004) is an autosomal recessive neurological disorder characterized by early onset macrocephaly, epilepsy, neurological deterioration with cerebellar ataxia and spasticity. An 8-month-old boy was admitted to our pediatric neurology clinic with macrocephaly. His brain magnetic resonance imaging (MRI) revealed bilateral, diffuse, symmetric structural white matter abnormalities, relatively sparing the cerebellum and bilateral subcortical temporal cysts. The diagnosis of Van der Knaap disease was suspected based on the clinical features and imaging findings and the genetic analysis revealed a novel homozygous c.768+2T>C mutation of the MLC1 gene. For determination of the novel splice-site mutation's effect, cDNA amplification was performed. cDNA analysis showed that the splice-site c.768+2T>C mutation gave rise to exon 9 skipping.
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Hwang J, Vu HM, Kim MS, Lim HH. Plasma membrane localization of MLC1 regulates cellular morphology and motility. Mol Brain 2019; 12:116. [PMID: 31888684 PMCID: PMC6938022 DOI: 10.1186/s13041-019-0540-6] [Citation(s) in RCA: 14] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/12/2019] [Accepted: 12/18/2019] [Indexed: 01/01/2023] Open
Abstract
Background Megalencephalic leukoencephalopathy with subcortical cysts (MLC) is a rare form of infantile-onset leukodystrophy. The disorder is caused primarily by mutations of MLC1 that leads to a series of phenotypic outcomes including vacuolation of myelin and astrocytes, subcortical cysts, brain edema, and macrocephaly. Recent studies have indicated that functional interactions among MLC1, GlialCAM, and ClC-2 channels play key roles in the regulation of neuronal, glial and vascular homeostasis. However, the physiological role of MLC1 in cellular homeostatic communication remains poorly understood. In the present study, we investigated the cellular function of MLC1 and its effects on cell–cell interactions. Methods MLC1-dependent cellular morphology and motility were analyzed by using confocal and live cell imaging technique. Biochemical approaches such as immunoblotting, co-immunoprecipitation, and surface biotinylation were conducted to support data. Results We found that the altered MLC1 expression and localization led to a great alteration in cellular morphology and motility through actin remodeling. MLC1 overexpression induced filopodia formation and suppressed motility. And, MLC1 proteins expressed in patient-derived MLC1 mutants resulted in trapping in the ER although no changes in morphology or motility were observed. Interestingly knockdown of Mlc1 induced Arp3-Cortactin interaction, lamellipodia formation, and increased the membrane ruffling of the astrocytes. These data indicate that subcellular localization of expressed MLC1 at the plasma membrane is critical for changes in actin dynamics through ARP2/3 complex. Thus, our results suggest that misallocation of pathogenic mutant MLC1 may disturbs the stable cell-cell communication and the homeostatic regulation of astrocytes in patients with MLC.
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Affiliation(s)
- Junmo Hwang
- Molecular Physiology and Biophysics Laboratory, Neurovascular Unit Research Group, Korea Brain Research Institute (KBRI), 41062, Daegu, Republic of Korea
| | - Hung M Vu
- Department of New Biology, Daegu Gyeongbuk Institute of Science & Technology (DGIST), 42988, Daegu, Republic of Korea
| | - Min-Sik Kim
- Department of New Biology, Daegu Gyeongbuk Institute of Science & Technology (DGIST), 42988, Daegu, Republic of Korea
| | - Hyun-Ho Lim
- Molecular Physiology and Biophysics Laboratory, Neurovascular Unit Research Group, Korea Brain Research Institute (KBRI), 41062, Daegu, Republic of Korea. .,Department of Brain & Cognitive Sciences, Daegu Gyeongbuk Institute of Science & Technology (DGIST), 42988, Daegu, Republic of Korea.
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Abstract
Leukodystrophies are genetically determined disorders affecting the white matter of the central nervous system. The combination of MRI pattern recognition and next-generation sequencing for the definition of novel disease entities has recently demonstrated that many leukodystrophies are due to the primary involvement and/or mutations in genes selectively expressed by cell types other than the oligodendrocytes, the myelin-forming cells in the brain. This has led to a new definition of leukodystrophies as genetic white matter disorders resulting from the involvement of any white matter structural component. As a result, the research has shifted its main focus from oligodendrocytes to other types of neuroglia. Astrocytes are the housekeeping cells of the nervous system, responsible for maintaining homeostasis and normal brain physiology and to orchestrate repair upon injury. Several lines of evidence show that astrocytic interactions with the other white matter cellular constituents play a primary pathophysiologic role in many leukodystrophies. These are thus now classified as astrocytopathies. This chapter addresses how the crosstalk between astrocytes, other glial cells, axons and non-neural cells are essential for the integrity and maintenance of the white matter in health. It also addresses the current knowledge of the cellular pathomechanisms of astrocytic leukodystrophies, and specifically Alexander disease, vanishing white matter, megalencephalic leukoencephalopathy with subcortical cysts and Aicardi-Goutière Syndrome.
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Affiliation(s)
- M S Jorge
- Department of Pathology, Free University Medical Centre, Amsterdam, The Netherlands
| | - Marianna Bugiani
- Department of Pathology, Free University Medical Centre, Amsterdam, The Netherlands.
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Min R, van der Knaap MS. Genetic defects disrupting glial ion and water homeostasis in the brain. Brain Pathol 2019; 28:372-387. [PMID: 29740942 PMCID: PMC8028498 DOI: 10.1111/bpa.12602] [Citation(s) in RCA: 30] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/24/2017] [Accepted: 03/02/2018] [Indexed: 12/23/2022] Open
Abstract
Electrical activity of neurons in the brain, caused by the movement of ions between intracellular and extracellular compartments, is the basis of all our thoughts and actions. Maintaining the correct ionic concentration gradients is therefore crucial for brain functioning. Ion fluxes are accompanied by the displacement of osmotically obliged water. Since even minor brain swelling leads to severe brain damage and even death, brain ion and water movement has to be tightly regulated. Glial cells, in particular astrocytes, play a key role in ion and water homeostasis. They are endowed with specific channels, pumps and carriers to regulate ion and water flow. Glial cells form a large panglial syncytium to aid the uptake and dispersal of ions and water, and make extensive contacts with brain fluid barriers for disposal of excess ions and water. Genetic defects in glial proteins involved in ion and water homeostasis disrupt brain functioning, thereby leading to neurological diseases. Since white matter edema is often a hallmark disease feature, many of these diseases are characterized as leukodystrophies. In this review we summarize our current understanding of inherited glial diseases characterized by disturbed brain ion and water homeostasis by integrating findings from MRI, genetics, neuropathology and animal models for disease. We discuss how mutations in different glial proteins lead to disease, and highlight the similarities and differences between these diseases. To come to effective therapies for this group of diseases, a better mechanistic understanding of how glial cells shape ion and water movement in the brain is crucial.
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Affiliation(s)
- Rogier Min
- Department of Child Neurology, Amsterdam Neuroscience, VU University Medical Center, Amsterdam, The Netherlands.,Department of Integrative Neurophysiology, Center for Neurogenomics and Cognitive Research, Amsterdam Neuroscience, VU University, Amsterdam, The Netherlands
| | - Marjo S van der Knaap
- Department of Child Neurology, Amsterdam Neuroscience, VU University Medical Center, Amsterdam, The Netherlands.,Department of Functional Genomics, Center for Neurogenomics and Cognitive Research, Amsterdam Neuroscience, VU University, Amsterdam, The Netherlands
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Identification in Chinese patients with GLIALCAM mutations of megalencephalic leukoencephalopathy with subcortical cysts and brain pathological study on Glialcam knock-in mouse models. World J Pediatr 2019; 15:454-464. [PMID: 31372844 PMCID: PMC6785595 DOI: 10.1007/s12519-019-00284-w] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 03/17/2019] [Accepted: 06/25/2019] [Indexed: 10/26/2022]
Abstract
BACKGROUND Megalencephalic leukoencephalopathy with subcortical cysts (MLC) is a rare neurological degenerative disorder caused by the mutations of MLC1 or GLIALCAM with autosomal recessive or autosomal dominant inheritance and a different prognosis, characterized by macrocephaly, delayed motor and cognitive development, and bilateral abnormal signals in cerebral white matter (WM) with or without cysts on magnetic resonance imaging (MRI). This study aimed to reveal the clinical and genetic features of MLC patients with GLIALCAM mutations and to explore the brain pathological characteristics and prognosis of mouse models with different modes of inheritance. METHODS Clinical information and peripheral venous blood were collected from six families. Genetic analysis was performed by Sanger sequencing of GLIALCAM. GlialcamArg92Trp/+ and GlialcamLys68Met/Thr132Asn mouse models were generated based on mutations from patients (c.274C>T(p.Arg92Trp) (c.203A>T(p.Lys68Met), and c.395C>A (p.Thr132Asn))). Brain pathologies of the mouse models at different time points were analyzed. RESULTS Six patients were clinically diagnosed with MLC. Of the six patients, five (Pt1-Pt5) presented with a heterozygous mutation in GLIALCAM (c.274C>T(p.Arg92Trp) or c.275G>C(p.Arg92Pro)) and were diagnosed with MLC2B; the remaining patient (Pt6) with two compound heterozygous mutations in GLIALCAM (c.203A>T (p.Lys68Met) and c.395C>A (p.Thr132Asn)) was diagnosed with MLC2A. The mutation c.275C>G (p.Arg92Pro) has not been reported before. Clinical manifestations of the patient with MLC2A (Pt6) progressed with regression, whereas the course of the five MLC2B patients remained stable or improved. The GlialcamArg92Trp/+ and GlialcamLys68Met/ Thr132Asn mouse models showed vacuolization in the anterior commissural WM at 1 month of age and vacuolization in the cerebellar WM at 3 and 6 months, respectively. At 9 months, the vacuolization of the GlialcamLys68Met/ Thr132Asn mouse model was heavier than that of the GlialcamArg92Trp/+ mouse model. Decreased expression of Glialcam in GlialcamArg92Trp/+ and GlialcamLys68Met/ Thr132Asn mice may contribute to the vacuolization. CONCLUSIONS Clinical and genetic characterization of patients with MLC and GLIALCAM mutations revealed a novel mutation, expanding the spectrum of GLIALCAM mutations. The first Glialcam mouse model with autosomal recessive inheritance and a new Glialcam mouse model with autosomal dominant inheritance were generated. The two mouse models with different modes of inheritance showed different degrees of brain pathological features, which were consistent with the patients' phenotype and further confirmed the pathogenicity of the corresponding mutations.
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Porciuncula R, Spada PKWDS, Goulart KOB. LEUKOENCEPHALOPATHY WITH EVANESCENT WHITE MATTER: A CASE REPORT. REVISTA PAULISTA DE PEDIATRIA 2018; 36:515-518. [PMID: 29995139 PMCID: PMC6322808 DOI: 10.1590/1984-0462/;2018;36;4;00001] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Subscribe] [Scholar Register] [Received: 03/09/2017] [Accepted: 07/28/2017] [Indexed: 12/04/2022]
Abstract
Objective: To describe the case of a child diagnosed with leukoencephalopathy with
vanishing white matter (LVWM), a rare genetic disease with autosomal
recessive inheritance pattern. Case description: A 5-month-old male child started to refuse breast-feeding, showing
somnolence and signs of dehydration,with dry mouth, increasing body
temperature and adipsy. As days went by, the symptoms got worse. The infant
was very sleepy and was transferred to the intensive care unit, where he
stayed for one week. At this time, a signal alteration with hyper attenuated
T2 predominance was identified in the magnetic resonance imaging,
compromising the white matter, which had diffuse and symmetrical aspect. At
this time, the infant started to present seizures. When the infant was 11
months old, he was diagnosed with tonsillitis and presented recurrent fever
peaks and extreme sleepiness. After hospital admission, the infant
progressed to a comatose state and died. The diagnosis of LVWM was confirmed
in examinations performed after death. As a late diagnosis, a genetic
disease was identified with a mutation in one of the five genes responsible
for the codification of complex eukaryotic translation initiation factor 2B
(eIF2B), involved with the control of the protein translation and which is
described as pathogenic in individuals with LVWM. Comments: LVWM is a hereditary brain disease that occurs primarily in children. The
disease is chronic and progressive, with additional episodes of rapid
deterioration, as shown in the present case report.
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Hamilton EMC, Tekturk P, Cialdella F, van Rappard DF, Wolf NI, Yalcinkaya C, Çetinçelik Ü, Rajaee A, Kariminejad A, Paprocka J, Yapici Z, Bošnjak VM, van der Knaap MS. Megalencephalic leukoencephalopathy with subcortical cysts: Characterization of disease variants. Neurology 2018; 90:e1395-e1403. [PMID: 29661901 PMCID: PMC5902784 DOI: 10.1212/wnl.0000000000005334] [Citation(s) in RCA: 36] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/14/2017] [Accepted: 01/16/2018] [Indexed: 01/08/2023] Open
Abstract
Objective To provide an overview of clinical and MRI characteristics of the different variants of the leukodystrophy megalencephalic leukoencephalopathy with subcortical cysts (MLC) and identify possible differentiating features. Methods We performed an international multi-institutional, cross-sectional observational study of the clinical and MRI characteristics in patients with genetically confirmed MLC. Clinical information was obtained by questionnaires for physicians and retrospective chart review. Results We included 204 patients with classic MLC, 187 of whom had recessive mutations in MLC1 (MLC1 variant) and 17 in GLIALCAM (MLC2A variant) and 38 patients with remitting MLC caused by dominant GLIALCAM mutations (MLC2B variant). We observed a relatively wide variability in neurologic disability among patients with classic MLC. No clinical differences could be identified between patients with MLC1 and MLC2A. Patients with MLC2B invariably had a milder phenotype with preservation of motor function, while intellectual disability and autism were relatively frequent. Systematic MRI review revealed no MRI features that distinguish between MLC1 and MLC2A. Radiologic improvement was observed in all patients with MLC2B and also in 2 patients with MLC1. In MRIs obtained in the early disease stage, absence of signal abnormalities of the posterior limb of the internal capsule and cerebellar white matter and presence of only rarefied subcortical white matter instead of true subcortical cysts were suggestive of MLC2B. Conclusion Clinical and MRI features did not distinguish between classic MLC with MLC1 or GLIALCAM mutations. Absence of signal abnormalities of the internal capsule and cerebellar white matter are MRI findings that point to the remitting phenotype.
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Affiliation(s)
- Eline M C Hamilton
- From the Department of Child Neurology and Amsterdam Neuroscience (E.M.C.H., F.C., D.F.v.R., N.I.W., M.S.v.d.K.), VU University Medical Center, Amsterdam, the Netherlands; Division of Child Neurology, Department of Neurology, Istanbul Faculty of Medicine (P.T., Z.Y.), and Division of Child Neurology, Department of Neurology, Cerrahpasa Medical School (C.Y.), Istanbul University; clinical geneticist in private practice (Ü.Ç.), Merkez Mahallesi, İstanbul, Turkey; Kariminejad-Najmabadi Pathology & Genetics Center (A.R., A.K.), Tehran, Iran; Department of Pediatric Neurology (J.P.), School of Medicine in Katowice, Medical University of Silesia, Katowice, Poland; Department of Neuropediatrics (V.M.B.), Children's Hospital Zagreb, School of Medicine, University of Zagreb, Croatia; and Department of Functional Genomics (M.S.v.d.K.), Center for Neurogenomics and Cognitive Research, Amsterdam Neuroscience, VU University, Amsterdam, the Netherlands
| | - Pinar Tekturk
- From the Department of Child Neurology and Amsterdam Neuroscience (E.M.C.H., F.C., D.F.v.R., N.I.W., M.S.v.d.K.), VU University Medical Center, Amsterdam, the Netherlands; Division of Child Neurology, Department of Neurology, Istanbul Faculty of Medicine (P.T., Z.Y.), and Division of Child Neurology, Department of Neurology, Cerrahpasa Medical School (C.Y.), Istanbul University; clinical geneticist in private practice (Ü.Ç.), Merkez Mahallesi, İstanbul, Turkey; Kariminejad-Najmabadi Pathology & Genetics Center (A.R., A.K.), Tehran, Iran; Department of Pediatric Neurology (J.P.), School of Medicine in Katowice, Medical University of Silesia, Katowice, Poland; Department of Neuropediatrics (V.M.B.), Children's Hospital Zagreb, School of Medicine, University of Zagreb, Croatia; and Department of Functional Genomics (M.S.v.d.K.), Center for Neurogenomics and Cognitive Research, Amsterdam Neuroscience, VU University, Amsterdam, the Netherlands
| | - Fia Cialdella
- From the Department of Child Neurology and Amsterdam Neuroscience (E.M.C.H., F.C., D.F.v.R., N.I.W., M.S.v.d.K.), VU University Medical Center, Amsterdam, the Netherlands; Division of Child Neurology, Department of Neurology, Istanbul Faculty of Medicine (P.T., Z.Y.), and Division of Child Neurology, Department of Neurology, Cerrahpasa Medical School (C.Y.), Istanbul University; clinical geneticist in private practice (Ü.Ç.), Merkez Mahallesi, İstanbul, Turkey; Kariminejad-Najmabadi Pathology & Genetics Center (A.R., A.K.), Tehran, Iran; Department of Pediatric Neurology (J.P.), School of Medicine in Katowice, Medical University of Silesia, Katowice, Poland; Department of Neuropediatrics (V.M.B.), Children's Hospital Zagreb, School of Medicine, University of Zagreb, Croatia; and Department of Functional Genomics (M.S.v.d.K.), Center for Neurogenomics and Cognitive Research, Amsterdam Neuroscience, VU University, Amsterdam, the Netherlands
| | - Diane F van Rappard
- From the Department of Child Neurology and Amsterdam Neuroscience (E.M.C.H., F.C., D.F.v.R., N.I.W., M.S.v.d.K.), VU University Medical Center, Amsterdam, the Netherlands; Division of Child Neurology, Department of Neurology, Istanbul Faculty of Medicine (P.T., Z.Y.), and Division of Child Neurology, Department of Neurology, Cerrahpasa Medical School (C.Y.), Istanbul University; clinical geneticist in private practice (Ü.Ç.), Merkez Mahallesi, İstanbul, Turkey; Kariminejad-Najmabadi Pathology & Genetics Center (A.R., A.K.), Tehran, Iran; Department of Pediatric Neurology (J.P.), School of Medicine in Katowice, Medical University of Silesia, Katowice, Poland; Department of Neuropediatrics (V.M.B.), Children's Hospital Zagreb, School of Medicine, University of Zagreb, Croatia; and Department of Functional Genomics (M.S.v.d.K.), Center for Neurogenomics and Cognitive Research, Amsterdam Neuroscience, VU University, Amsterdam, the Netherlands
| | - Nicole I Wolf
- From the Department of Child Neurology and Amsterdam Neuroscience (E.M.C.H., F.C., D.F.v.R., N.I.W., M.S.v.d.K.), VU University Medical Center, Amsterdam, the Netherlands; Division of Child Neurology, Department of Neurology, Istanbul Faculty of Medicine (P.T., Z.Y.), and Division of Child Neurology, Department of Neurology, Cerrahpasa Medical School (C.Y.), Istanbul University; clinical geneticist in private practice (Ü.Ç.), Merkez Mahallesi, İstanbul, Turkey; Kariminejad-Najmabadi Pathology & Genetics Center (A.R., A.K.), Tehran, Iran; Department of Pediatric Neurology (J.P.), School of Medicine in Katowice, Medical University of Silesia, Katowice, Poland; Department of Neuropediatrics (V.M.B.), Children's Hospital Zagreb, School of Medicine, University of Zagreb, Croatia; and Department of Functional Genomics (M.S.v.d.K.), Center for Neurogenomics and Cognitive Research, Amsterdam Neuroscience, VU University, Amsterdam, the Netherlands
| | - Cengiz Yalcinkaya
- From the Department of Child Neurology and Amsterdam Neuroscience (E.M.C.H., F.C., D.F.v.R., N.I.W., M.S.v.d.K.), VU University Medical Center, Amsterdam, the Netherlands; Division of Child Neurology, Department of Neurology, Istanbul Faculty of Medicine (P.T., Z.Y.), and Division of Child Neurology, Department of Neurology, Cerrahpasa Medical School (C.Y.), Istanbul University; clinical geneticist in private practice (Ü.Ç.), Merkez Mahallesi, İstanbul, Turkey; Kariminejad-Najmabadi Pathology & Genetics Center (A.R., A.K.), Tehran, Iran; Department of Pediatric Neurology (J.P.), School of Medicine in Katowice, Medical University of Silesia, Katowice, Poland; Department of Neuropediatrics (V.M.B.), Children's Hospital Zagreb, School of Medicine, University of Zagreb, Croatia; and Department of Functional Genomics (M.S.v.d.K.), Center for Neurogenomics and Cognitive Research, Amsterdam Neuroscience, VU University, Amsterdam, the Netherlands
| | - Ümran Çetinçelik
- From the Department of Child Neurology and Amsterdam Neuroscience (E.M.C.H., F.C., D.F.v.R., N.I.W., M.S.v.d.K.), VU University Medical Center, Amsterdam, the Netherlands; Division of Child Neurology, Department of Neurology, Istanbul Faculty of Medicine (P.T., Z.Y.), and Division of Child Neurology, Department of Neurology, Cerrahpasa Medical School (C.Y.), Istanbul University; clinical geneticist in private practice (Ü.Ç.), Merkez Mahallesi, İstanbul, Turkey; Kariminejad-Najmabadi Pathology & Genetics Center (A.R., A.K.), Tehran, Iran; Department of Pediatric Neurology (J.P.), School of Medicine in Katowice, Medical University of Silesia, Katowice, Poland; Department of Neuropediatrics (V.M.B.), Children's Hospital Zagreb, School of Medicine, University of Zagreb, Croatia; and Department of Functional Genomics (M.S.v.d.K.), Center for Neurogenomics and Cognitive Research, Amsterdam Neuroscience, VU University, Amsterdam, the Netherlands
| | - Ahmad Rajaee
- From the Department of Child Neurology and Amsterdam Neuroscience (E.M.C.H., F.C., D.F.v.R., N.I.W., M.S.v.d.K.), VU University Medical Center, Amsterdam, the Netherlands; Division of Child Neurology, Department of Neurology, Istanbul Faculty of Medicine (P.T., Z.Y.), and Division of Child Neurology, Department of Neurology, Cerrahpasa Medical School (C.Y.), Istanbul University; clinical geneticist in private practice (Ü.Ç.), Merkez Mahallesi, İstanbul, Turkey; Kariminejad-Najmabadi Pathology & Genetics Center (A.R., A.K.), Tehran, Iran; Department of Pediatric Neurology (J.P.), School of Medicine in Katowice, Medical University of Silesia, Katowice, Poland; Department of Neuropediatrics (V.M.B.), Children's Hospital Zagreb, School of Medicine, University of Zagreb, Croatia; and Department of Functional Genomics (M.S.v.d.K.), Center for Neurogenomics and Cognitive Research, Amsterdam Neuroscience, VU University, Amsterdam, the Netherlands
| | - Ariana Kariminejad
- From the Department of Child Neurology and Amsterdam Neuroscience (E.M.C.H., F.C., D.F.v.R., N.I.W., M.S.v.d.K.), VU University Medical Center, Amsterdam, the Netherlands; Division of Child Neurology, Department of Neurology, Istanbul Faculty of Medicine (P.T., Z.Y.), and Division of Child Neurology, Department of Neurology, Cerrahpasa Medical School (C.Y.), Istanbul University; clinical geneticist in private practice (Ü.Ç.), Merkez Mahallesi, İstanbul, Turkey; Kariminejad-Najmabadi Pathology & Genetics Center (A.R., A.K.), Tehran, Iran; Department of Pediatric Neurology (J.P.), School of Medicine in Katowice, Medical University of Silesia, Katowice, Poland; Department of Neuropediatrics (V.M.B.), Children's Hospital Zagreb, School of Medicine, University of Zagreb, Croatia; and Department of Functional Genomics (M.S.v.d.K.), Center for Neurogenomics and Cognitive Research, Amsterdam Neuroscience, VU University, Amsterdam, the Netherlands
| | - Justyna Paprocka
- From the Department of Child Neurology and Amsterdam Neuroscience (E.M.C.H., F.C., D.F.v.R., N.I.W., M.S.v.d.K.), VU University Medical Center, Amsterdam, the Netherlands; Division of Child Neurology, Department of Neurology, Istanbul Faculty of Medicine (P.T., Z.Y.), and Division of Child Neurology, Department of Neurology, Cerrahpasa Medical School (C.Y.), Istanbul University; clinical geneticist in private practice (Ü.Ç.), Merkez Mahallesi, İstanbul, Turkey; Kariminejad-Najmabadi Pathology & Genetics Center (A.R., A.K.), Tehran, Iran; Department of Pediatric Neurology (J.P.), School of Medicine in Katowice, Medical University of Silesia, Katowice, Poland; Department of Neuropediatrics (V.M.B.), Children's Hospital Zagreb, School of Medicine, University of Zagreb, Croatia; and Department of Functional Genomics (M.S.v.d.K.), Center for Neurogenomics and Cognitive Research, Amsterdam Neuroscience, VU University, Amsterdam, the Netherlands
| | - Zuhal Yapici
- From the Department of Child Neurology and Amsterdam Neuroscience (E.M.C.H., F.C., D.F.v.R., N.I.W., M.S.v.d.K.), VU University Medical Center, Amsterdam, the Netherlands; Division of Child Neurology, Department of Neurology, Istanbul Faculty of Medicine (P.T., Z.Y.), and Division of Child Neurology, Department of Neurology, Cerrahpasa Medical School (C.Y.), Istanbul University; clinical geneticist in private practice (Ü.Ç.), Merkez Mahallesi, İstanbul, Turkey; Kariminejad-Najmabadi Pathology & Genetics Center (A.R., A.K.), Tehran, Iran; Department of Pediatric Neurology (J.P.), School of Medicine in Katowice, Medical University of Silesia, Katowice, Poland; Department of Neuropediatrics (V.M.B.), Children's Hospital Zagreb, School of Medicine, University of Zagreb, Croatia; and Department of Functional Genomics (M.S.v.d.K.), Center for Neurogenomics and Cognitive Research, Amsterdam Neuroscience, VU University, Amsterdam, the Netherlands
| | - Vlatka Mejaški Bošnjak
- From the Department of Child Neurology and Amsterdam Neuroscience (E.M.C.H., F.C., D.F.v.R., N.I.W., M.S.v.d.K.), VU University Medical Center, Amsterdam, the Netherlands; Division of Child Neurology, Department of Neurology, Istanbul Faculty of Medicine (P.T., Z.Y.), and Division of Child Neurology, Department of Neurology, Cerrahpasa Medical School (C.Y.), Istanbul University; clinical geneticist in private practice (Ü.Ç.), Merkez Mahallesi, İstanbul, Turkey; Kariminejad-Najmabadi Pathology & Genetics Center (A.R., A.K.), Tehran, Iran; Department of Pediatric Neurology (J.P.), School of Medicine in Katowice, Medical University of Silesia, Katowice, Poland; Department of Neuropediatrics (V.M.B.), Children's Hospital Zagreb, School of Medicine, University of Zagreb, Croatia; and Department of Functional Genomics (M.S.v.d.K.), Center for Neurogenomics and Cognitive Research, Amsterdam Neuroscience, VU University, Amsterdam, the Netherlands
| | - Marjo S van der Knaap
- From the Department of Child Neurology and Amsterdam Neuroscience (E.M.C.H., F.C., D.F.v.R., N.I.W., M.S.v.d.K.), VU University Medical Center, Amsterdam, the Netherlands; Division of Child Neurology, Department of Neurology, Istanbul Faculty of Medicine (P.T., Z.Y.), and Division of Child Neurology, Department of Neurology, Cerrahpasa Medical School (C.Y.), Istanbul University; clinical geneticist in private practice (Ü.Ç.), Merkez Mahallesi, İstanbul, Turkey; Kariminejad-Najmabadi Pathology & Genetics Center (A.R., A.K.), Tehran, Iran; Department of Pediatric Neurology (J.P.), School of Medicine in Katowice, Medical University of Silesia, Katowice, Poland; Department of Neuropediatrics (V.M.B.), Children's Hospital Zagreb, School of Medicine, University of Zagreb, Croatia; and Department of Functional Genomics (M.S.v.d.K.), Center for Neurogenomics and Cognitive Research, Amsterdam Neuroscience, VU University, Amsterdam, the Netherlands.
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Dubey M, Brouwers E, Hamilton EM, Stiedl O, Bugiani M, Koch H, Kole MH, Boschert U, Wykes RC, Mansvelder HD, van der Knaap MS, Min R. Seizures and disturbed brain potassium dynamics in the leukodystrophy megalencephalic leukoencephalopathy with subcortical cysts. Ann Neurol 2018; 83:636-649. [PMID: 29466841 PMCID: PMC5900999 DOI: 10.1002/ana.25190] [Citation(s) in RCA: 25] [Impact Index Per Article: 4.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/26/2017] [Revised: 01/12/2018] [Accepted: 02/18/2018] [Indexed: 12/26/2022]
Abstract
OBJECTIVE Loss of function of the astrocyte-specific protein MLC1 leads to the childhood-onset leukodystrophy "megalencephalic leukoencephalopathy with subcortical cysts" (MLC). Studies on isolated cells show a role for MLC1 in astrocyte volume regulation and suggest that disturbed brain ion and water homeostasis is central to the disease. Excitability of neuronal networks is particularly sensitive to ion and water homeostasis. In line with this, reports of seizures and epilepsy in MLC patients exist. However, systematic assessment and mechanistic understanding of seizures in MLC are lacking. METHODS We analyzed an MLC patient inventory to study occurrence of seizures in MLC. We used two distinct genetic mouse models of MLC to further study epileptiform activity and seizure threshold through wireless extracellular field potential recordings. Whole-cell patch-clamp recordings and K+ -sensitive electrode recordings in mouse brain slices were used to explore the underlying mechanisms of epilepsy in MLC. RESULTS An early onset of seizures is common in MLC. Similarly, in MLC mice, we uncovered spontaneous epileptiform brain activity and a lowered threshold for induced seizures. At the cellular level, we found that although passive and active properties of individual pyramidal neurons are unchanged, extracellular K+ dynamics and neuronal network activity are abnormal in MLC mice. INTERPRETATION Disturbed astrocyte regulation of ion and water homeostasis in MLC causes hyperexcitability of neuronal networks and seizures. These findings suggest a role for defective astrocyte volume regulation in epilepsy. Ann Neurol 2018;83:636-649.
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Affiliation(s)
- Mohit Dubey
- Department of Child Neurology, Amsterdam NeuroscienceVU University Medical CenterAmsterdamThe Netherlands
- Department of Integrative Neurophysiology, Center for Neurogenomics and Cognitive Research, Amsterdam NeuroscienceVU UniversityAmsterdamThe Netherlands
- Present address:
Current address for Mohit Dubey: Department of Axonal SignalingNetherlands Institute for Neuroscience, Royal Netherlands Academy of Arts and SciencesAmsterdamThe Netherlands
| | - Eelke Brouwers
- Department of Child Neurology, Amsterdam NeuroscienceVU University Medical CenterAmsterdamThe Netherlands
- Department of Integrative Neurophysiology, Center for Neurogenomics and Cognitive Research, Amsterdam NeuroscienceVU UniversityAmsterdamThe Netherlands
| | - Eline M.C. Hamilton
- Department of Child Neurology, Amsterdam NeuroscienceVU University Medical CenterAmsterdamThe Netherlands
| | - Oliver Stiedl
- Department of Functional Genomics, Center for Neurogenomics and Cognitive Research, Amsterdam NeuroscienceVU UniversityAmsterdamThe Netherlands
- Department of Molecular and Cellular Neurobiology, Center for Neurogenomics and Cognitive Research, Amsterdam NeuroscienceVU UniversityAmsterdamThe Netherlands
| | - Marianna Bugiani
- Department of Child Neurology, Amsterdam NeuroscienceVU University Medical CenterAmsterdamThe Netherlands
- Department of PathologyVU University Medical CenterAmsterdamThe Netherlands
| | - Henner Koch
- Department of NeurologyUniversity of Tübingen, Hertie Institute for Clinical Brain ResearchTübingenGermany
| | - Maarten H.P. Kole
- Department of Axonal SignalingNetherlands Institute for Neuroscience, Royal Netherlands Academy of Arts and SciencesAmsterdamThe Netherlands
- Cell Biology, Faculty of ScienceUtrecht UniversityUtrechtThe Netherlands
| | - Ursula Boschert
- Translational Innovation Platform Immunology/Neurology, EMD Serono Research & Development InstituteBillericaMA
| | - Robert C. Wykes
- Department of Clinical & Experimental Epilepsy, UCL Institute of NeurologyUniversity College LondonLondonUnited Kingdom
| | - Huibert D. Mansvelder
- Department of Integrative Neurophysiology, Center for Neurogenomics and Cognitive Research, Amsterdam NeuroscienceVU UniversityAmsterdamThe Netherlands
| | - Marjo S. van der Knaap
- Department of Child Neurology, Amsterdam NeuroscienceVU University Medical CenterAmsterdamThe Netherlands
- Department of Functional Genomics, Center for Neurogenomics and Cognitive Research, Amsterdam NeuroscienceVU UniversityAmsterdamThe Netherlands
| | - Rogier Min
- Department of Child Neurology, Amsterdam NeuroscienceVU University Medical CenterAmsterdamThe Netherlands
- Department of Integrative Neurophysiology, Center for Neurogenomics and Cognitive Research, Amsterdam NeuroscienceVU UniversityAmsterdamThe Netherlands
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31
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Estévez R, Elorza-Vidal X, Gaitán-Peñas H, Pérez-Rius C, Armand-Ugón M, Alonso-Gardón M, Xicoy-Espaulella E, Sirisi S, Arnedo T, Capdevila-Nortes X, López-Hernández T, Montolio M, Duarri A, Teijido O, Barrallo-Gimeno A, Palacín M, Nunes V. Megalencephalic leukoencephalopathy with subcortical cysts: A personal biochemical retrospective. Eur J Med Genet 2018; 61:50-60. [DOI: 10.1016/j.ejmg.2017.10.013] [Citation(s) in RCA: 17] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/21/2017] [Revised: 09/14/2017] [Accepted: 10/22/2017] [Indexed: 12/22/2022]
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32
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Signorino G, Covaceuszach S, Bozzi M, Hübner W, Mönkemöller V, Konarev PV, Cassetta A, Brancaccio A, Sciandra F. A dystroglycan mutation (p.Cys667Phe) associated to muscle-eye-brain disease with multicystic leucodystrophy results in ER-retention of the mutant protein. Hum Mutat 2017; 39:266-280. [PMID: 29134705 DOI: 10.1002/humu.23370] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/07/2017] [Revised: 10/13/2017] [Accepted: 11/06/2017] [Indexed: 01/11/2023]
Abstract
Dystroglycan (DG) is a cell adhesion complex composed by two subunits, the highly glycosylated α-DG and the transmembrane β-DG. In skeletal muscle, DG is involved in dystroglycanopathies, a group of heterogeneous muscular dystrophies characterized by a reduced glycosylation of α-DG. The genes mutated in secondary dystroglycanopathies are involved in the synthesis of O-mannosyl glycans and in the O-mannosylation pathway of α-DG. Mutations in the DG gene (DAG1), causing primary dystroglycanopathies, destabilize the α-DG core protein influencing its binding to modifying enzymes. Recently, a homozygous mutation (p.Cys699Phe) hitting the β-DG ectodomain has been identified in a patient affected by muscle-eye-brain disease with multicystic leucodystrophy, suggesting that other mechanisms than hypoglycosylation of α-DG could be implicated in dystroglycanopathies. Herein, we have characterized the DG murine mutant counterpart by transfection in cellular systems and high-resolution microscopy. We observed that the mutation alters the DG processing leading to retention of its uncleaved precursor in the endoplasmic reticulum. Accordingly, small-angle X-ray scattering data, corroborated by biochemical and biophysical experiments, revealed that the mutation provokes an alteration in the β-DG ectodomain overall folding, resulting in disulfide-associated oligomerization. Our data provide the first evidence of a novel intracellular mechanism, featuring an anomalous endoplasmic reticulum-retention, underlying dystroglycanopathy.
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Affiliation(s)
- Giulia Signorino
- Istituto di Biochimica e Biochimica Clinica, Università Cattolica del Sacro Cuore, Roma, Italy
| | | | - Manuela Bozzi
- Istituto di Biochimica e Biochimica Clinica, Università Cattolica del Sacro Cuore, Roma, Italy.,Istituto di Chimica del Riconoscimento Molecolare - CNR c/o Istituto di Biochimica e Biochimica Clinica, Università Cattolica del Sacro Cuore, Roma, Italy
| | - Wolfgang Hübner
- Biomolecular Photonics, University of Bielefeld, Bielefeld, Germany
| | | | - Petr V Konarev
- A.V. Shubnikov Institute of Crystallography of Federal Scientific Research Centre "Crystallography and Photonics" of Russian Academy of Sciences, Leninsky prospect 59, Moscow, Russia
| | - Alberto Cassetta
- Istituto di Cristallografia - CNR, Trieste Outstation, Trieste, Italy
| | - Andrea Brancaccio
- Istituto di Chimica del Riconoscimento Molecolare - CNR c/o Istituto di Biochimica e Biochimica Clinica, Università Cattolica del Sacro Cuore, Roma, Italy.,School of Biochemistry, University of Bristol, Bristol, United Kingdom
| | - Francesca Sciandra
- Istituto di Chimica del Riconoscimento Molecolare - CNR c/o Istituto di Biochimica e Biochimica Clinica, Università Cattolica del Sacro Cuore, Roma, Italy
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33
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Toutounchian JJ, McCarty JH. Selective expression of eGFP in mouse perivascular astrocytes by modification of the Mlc1 gene using T2A-based ribosome skipping. Genesis 2017; 55. [PMID: 28929580 DOI: 10.1002/dvg.23071] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/08/2017] [Revised: 09/12/2017] [Accepted: 09/17/2017] [Indexed: 11/12/2022]
Abstract
Perivascular astrocyte end feet closely juxtapose cerebral blood vessels to regulate important developmental and physiological processes including endothelial cell proliferation and sprouting as well as the formation of the blood-brain barrier (BBB). The mechanisms underlying these events remain largely unknown due to a lack of experimental models for identifying perivascular astrocytes and distinguishing these cell types from other astroglial populations. Megalencephalic leukoencephalopathy with subcortical cysts 1 (Mlc1) is a transmembrane protein that is expressed in perivascular astrocyte end feet where it controls BBB development and homeostasis. On the basis of this knowledge, we used T2A peptide-skipping strategies to engineer a knock-in mouse model in which the endogenous Mlc1 gene drives expression of enhanced green fluorescent protein (eGFP), without impacting expression of Mlc1 protein. Analysis of fetal, neonatal and adult Mlc1-eGFP knock-in mice revealed a dynamic spatiotemporal expression pattern of eGFP in glial cells, including nestin-expressing neuroepithelial cells during development and glial fibrillary acidic protein (GFAP)-expressing perivascular astrocytes in the postnatal brain. EGFP was not expressed in neurons, microglia, oligodendroglia, or cerebral vascular cells. Analysis of angiogenesis in the neonatal retina also revealed enriched Mlc1-driven eGFP expression in perivascular astrocytes that contact sprouting blood vessels and regulate blood-retinal barrier permeability. A cortical injury model revealed that Mlc1-eGFP expression is progressively induced in reactive astrocytes that form a glial scar. Hence, Mlc1-eGFP knock-in mice are a new and powerful tool to identify perivascular astrocytes in the brain and retina and characterize how these cell types regulate cerebral blood vessel functions in health and disease.
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Affiliation(s)
- Jordan J Toutounchian
- Department of Neurosurgery, The University of Texas M. D. Anderson Cancer Center, Houston, Texas, 77030
| | - Joseph H McCarty
- Department of Neurosurgery, The University of Texas M. D. Anderson Cancer Center, Houston, Texas, 77030
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34
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van der Knaap MS, Bugiani M. Leukodystrophies: a proposed classification system based on pathological changes and pathogenetic mechanisms. Acta Neuropathol 2017; 134:351-382. [PMID: 28638987 PMCID: PMC5563342 DOI: 10.1007/s00401-017-1739-1] [Citation(s) in RCA: 222] [Impact Index Per Article: 31.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/14/2017] [Revised: 06/06/2017] [Accepted: 06/06/2017] [Indexed: 12/29/2022]
Abstract
Leukodystrophies are genetically determined disorders characterized by the selective involvement of the central nervous system white matter. Onset may be at any age, from prenatal life to senescence. Many leukodystrophies are degenerative in nature, but some only impair white matter function. The clinical course is mostly progressive, but may also be static or even improving with time. Progressive leukodystrophies are often fatal, and no curative treatment is known. The last decade has witnessed a tremendous increase in the number of defined leukodystrophies also owing to a diagnostic approach combining magnetic resonance imaging pattern recognition and next generation sequencing. Knowledge on white matter physiology and pathology has also dramatically built up. This led to the recognition that only few leukodystrophies are due to mutations in myelin- or oligodendrocyte-specific genes, and many are rather caused by defects in other white matter structural components, including astrocytes, microglia, axons and blood vessels. We here propose a novel classification of leukodystrophies that takes into account the primary involvement of any white matter component. Categories in this classification are the myelin disorders due to a primary defect in oligodendrocytes or myelin (hypomyelinating and demyelinating leukodystrophies, leukodystrophies with myelin vacuolization); astrocytopathies; leuko-axonopathies; microgliopathies; and leuko-vasculopathies. Following this classification, we illustrate the neuropathology and disease mechanisms of some leukodystrophies taken as example for each category. Some leukodystrophies fall into more than one category. Given the complex molecular and cellular interplay underlying white matter pathology, recognition of the cellular pathology behind a disease becomes crucial in addressing possible treatment strategies.
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Affiliation(s)
- Marjo S van der Knaap
- Department of Pediatrics/Child Neurology, VU University Medical Centre, Amsterdam Neuroscience, Amsterdam, The Netherlands
- Department of Functional Genomics, Centre for Neurogenomics and Cognitive Research, Amsterdam Neuroscience, VU University, Amsterdam, The Netherlands
| | - Marianna Bugiani
- Department of Pediatrics/Child Neurology, VU University Medical Centre, Amsterdam Neuroscience, Amsterdam, The Netherlands.
- Department of Pathology, VU University Medical Centre, Amsterdam Neuroscience, Amsterdam, The Netherlands.
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35
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Choi SA, Kim SY, Yoon J, Choi J, Park SS, Seong MW, Kim H, Hwang H, Choi JE, Chae JH, Kim KJ, Kim S, Lee YJ, Nam SO, Lim BC. A Unique Mutational Spectrum of MLC1 in Korean Patients With Megalencephalic Leukoencephalopathy With Subcortical Cysts: p.Ala275Asp Founder Mutation and Maternal Uniparental Disomy of Chromosome 22. Ann Lab Med 2017; 37:516-521. [PMID: 28840990 PMCID: PMC5587825 DOI: 10.3343/alm.2017.37.6.516] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/13/2017] [Revised: 03/18/2017] [Accepted: 06/25/2017] [Indexed: 11/30/2022] Open
Abstract
Background Megalencephalic leukoencephalopathy with subcortical cysts (MLC) is a rare inherited disorder characterized by infantile-onset macrocephaly, slow neurologic deterioration, and seizures. Mutations in the causative gene, MLC1, are found in approximately 75% of patients and are inherited in an autosomal recessive manner. We analyzed MLC1 mutations in five unrelated Korean patients with MLC. Methods Direct Sanger sequencing was used to identify MLC1 mutations. A founder effect of the p.Ala275Asp variant was demonstrated by haplotype analysis using single-nucleotide polymorphic (SNP) markers. Multiple ligation-dependent probe amplification (MLPA) and comparative genomic hybridization plus SNP array were used to detect exonic deletions or uniparental disomy (UPD). Results The most prevalent pathogenic variant was c.824C>A (p.Ala275Asp) found in 7/10 (70%) alleles. Two pathogenic frameshift variants were found: c.135delC (p.Cys46Alafs*12) and c.337_353delinsG (p.Ile113Glyfs*4). Haplotype analysis suggested that the Korean patients with MLC harbored a founder mutation in p.Ala275Asp. The p.(Ile113Glyfs*4) was identified in a homozygous state, and a family study revealed that only the mother was heterozygous for this variant. Further analysis of MLPA and SNP arrays for this patient demonstrated loss of heterozygosity of chromosome 22 without any deletion, indicating UPD. The maternal origin of both chromosomes 22 was demonstrated by haplotype analysis. Conclusions This study is the first to describe the mutational spectrum of Korean patients with MLC, demonstrating a founder effect of the p.Ala275Asp variant. This study also broadens our understanding of the mutational spectrum of MLC1 by demonstrating a homozygous p.(Ile113Glyfs*4) variant resulting from UPD of chromosome 22.
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Affiliation(s)
- Sun Ah Choi
- Department of Pediatrics, Pediatric Clinical Neuroscience Center, Seoul National University Children's Hospital, Seoul National University College of Medicine, Seoul, Korea
| | - Soo Yeon Kim
- Department of Pediatrics, Pediatric Clinical Neuroscience Center, Seoul National University Children's Hospital, Seoul National University College of Medicine, Seoul, Korea
| | - Jihoo Yoon
- Department of Laboratory Medicine, Seoul National University Hospital, Seoul National University College of Medicine, Seoul, Korea
| | - Joongmoon Choi
- Department of Laboratory Medicine, Seoul National University Hospital, Seoul National University College of Medicine, Seoul, Korea
| | - Sung Sup Park
- Department of Laboratory Medicine, Seoul National University Hospital, Seoul National University College of Medicine, Seoul, Korea.,Biomedical Research Institute, Seoul National University Hospital, Seoul, Korea
| | - Moon Woo Seong
- Department of Laboratory Medicine, Seoul National University Hospital, Seoul National University College of Medicine, Seoul, Korea.,Biomedical Research Institute, Seoul National University Hospital, Seoul, Korea.
| | - Hunmin Kim
- Department of Pediatrics, Seoul National University Bundang Hospital, Seongnam, Korea
| | - Hee Hwang
- Department of Pediatrics, Seoul National University Bundang Hospital, Seongnam, Korea
| | - Ji Eun Choi
- Department of Pediatrics, Seoul National University Boramae Medical Center, Seoul, Korea
| | - Jong Hee Chae
- Department of Pediatrics, Pediatric Clinical Neuroscience Center, Seoul National University Children's Hospital, Seoul National University College of Medicine, Seoul, Korea
| | - Ki Joong Kim
- Department of Pediatrics, Pediatric Clinical Neuroscience Center, Seoul National University Children's Hospital, Seoul National University College of Medicine, Seoul, Korea
| | - Seunghyo Kim
- Department of Pediatrics, Jeju National University Hospital, Jeju National University School of Medicine, Jeju, Korea
| | - Yun Jin Lee
- Department of Pediatrics, Pusan National University Children's Hospital, Pusan National University College of Medicine, Yangsan, Korea
| | - Sang Ook Nam
- Department of Pediatrics, Pusan National University Children's Hospital, Pusan National University College of Medicine, Yangsan, Korea
| | - Byung Chan Lim
- Department of Pediatrics, Pediatric Clinical Neuroscience Center, Seoul National University Children's Hospital, Seoul National University College of Medicine, Seoul, Korea.
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36
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Wang H, Xu M, Kong Q, Sun P, Yan F, Tian W, Wang X. Research and progress on ClC‑2 (Review). Mol Med Rep 2017; 16:11-22. [PMID: 28534947 PMCID: PMC5482133 DOI: 10.3892/mmr.2017.6600] [Citation(s) in RCA: 21] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/11/2016] [Accepted: 02/13/2017] [Indexed: 12/22/2022] Open
Abstract
Chloride channel 2 (ClC-2) is one of the nine mammalian members of the ClC family. The present review discusses the molecular properties of ClC‑2, including CLCN2, ClC‑2 promoter and the structural properties of ClC‑2 protein; physiological properties; functional properties, including the regulation of cell volume. The effects of ClC‑2 on the digestive, respiratory, circulatory, nervous and optical systems are also discussed, in addition to the mechanisms involved in the regulation of ClC‑2. The review then discusses the diseases associated with ClC‑2, including degeneration of the retina, Sjögren's syndrome, age‑related cataracts, degeneration of the testes, azoospermia, lung cancer, constipation, repair of impaired intestinal mucosa barrier, leukemia, cystic fibrosis, leukoencephalopathy, epilepsy and diabetes mellitus. It was concluded that future investigations of ClC‑2 are likely to be focused on developing specific drugs, activators and inhibitors regulating the expression of ClC‑2 to treat diseases associated with ClC‑2. The determination of CLCN2 is required to prevent and treat several diseases associated with ClC‑2.
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Affiliation(s)
- Hongwei Wang
- Department of Ophthalmology, People's Hospital of Jingjiang, Jingjiang, Jiangsu 214500, P.R. China
| | - Minghui Xu
- Library, Qiqihar Medical University, Qiqihar, Heilongjiang 161006, P.R. China
| | - Qingjie Kong
- School of Computer Science and Information Technology, Northeast Normal University, Changchun, Jilin 130024, P.R. China
| | - Peng Sun
- Department of Ophthalmology, The First Affiliated Hospital of Jiamusi University, Jiamusi, Heilongjiang 154000, P.R. China
| | - Fengyun Yan
- Assets Division, Harbin University of Science and Technology, Harbin, Heilongjiang 150080, P.R. China
| | - Wenying Tian
- Library, Qiqihar Medical University, Qiqihar, Heilongjiang 161006, P.R. China
| | - Xin Wang
- Library, Qiqihar Medical University, Qiqihar, Heilongjiang 161006, P.R. China
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37
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Dai CL, He WB, Du J, Tan YQ, Lu GX, Li W. A case of megalencephalic leukoencephalopathy with subcortical cysts type 1 was identified with a novel compound heterozygous alteration (c.135delC; c.423+2dupT) in China. Clin Case Rep 2017; 5:961-967. [PMID: 28588848 PMCID: PMC5458048 DOI: 10.1002/ccr3.986] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/24/2015] [Revised: 03/14/2017] [Accepted: 03/19/2017] [Indexed: 11/08/2022] Open
Abstract
We report a compound heterozygous mutation (c.135delC; c.423+2dupT) of MLC1 gene in a Chinese patient underlying infantile macrocephaly and neurological deterioration in early childhood. Brain MRI revealed diffusion abnormality in swollen white matter and a subcortical cyst. The cDNA sequencing analysis for the c.423+2dupT variant revealed skipping of exon 5.
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Affiliation(s)
- Cong-Ling Dai
- Institute of Reproductive and Stem Cell Engineering Central South University Hunan 410008 China
| | - Wen-Bin He
- Institute of Reproductive and Stem Cell Engineering Central South University Hunan 410008 China.,Reproductive and Genetic Hospital of Citic-Xiangya Hunan 410008 China
| | - Juan Du
- Institute of Reproductive and Stem Cell Engineering Central South University Hunan 410008 China.,Reproductive and Genetic Hospital of Citic-Xiangya Hunan 410008 China
| | - Yue-Qiu Tan
- Institute of Reproductive and Stem Cell Engineering Central South University Hunan 410008 China.,Reproductive and Genetic Hospital of Citic-Xiangya Hunan 410008 China
| | - Guang-Xiu Lu
- Institute of Reproductive and Stem Cell Engineering Central South University Hunan 410008 China.,Reproductive and Genetic Hospital of Citic-Xiangya Hunan 410008 China.,National Engineering and Research Center of Human Stem Cells Changsha Hunan 410000 China
| | - Wen Li
- Institute of Reproductive and Stem Cell Engineering Central South University Hunan 410008 China.,Reproductive and Genetic Hospital of Citic-Xiangya Hunan 410008 China
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38
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Sirisi S, Elorza-Vidal X, Arnedo T, Armand-Ugón M, Callejo G, Capdevila-Nortes X, López-Hernández T, Schulte U, Barrallo-Gimeno A, Nunes V, Gasull X, Estévez R. Depolarization causes the formation of a ternary complex between GlialCAM, MLC1 and ClC-2 in astrocytes: implications in megalencephalic leukoencephalopathy. Hum Mol Genet 2017; 26:2436-2450. [DOI: 10.1093/hmg/ddx134] [Citation(s) in RCA: 27] [Impact Index Per Article: 3.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/22/2017] [Accepted: 03/29/2017] [Indexed: 01/06/2023] Open
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39
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The Pediatric Cerebellum in Inherited Neurodegenerative Disorders: A Pattern-recognition Approach. Neuroimaging Clin N Am 2017; 26:373-416. [PMID: 27423800 DOI: 10.1016/j.nic.2016.03.007] [Citation(s) in RCA: 15] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
Abstract
Evaluation of imaging studies of the cerebellum in inherited neurodegenerative disorders is aided by attention to neuroimaging patterns based on anatomic determinants, including biometric analysis, hyperintense signal of structures, including the cerebellar cortex, white matter, dentate nuclei, brainstem tracts, and nuclei, the presence of cysts, brain iron, or calcifications, change over time, the use of diffusion-weighted/diffusion tensor imaging and T2*-weighted sequences, magnetic resonance spectroscopy; and, in rare occurrences, the administration of contrast material.
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40
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Falik Zaccai TC, Savitzki D, Zivony-Elboum Y, Vilboux T, Fitts EC, Shoval Y, Kalfon L, Samra N, Keren Z, Gross B, Chasnyk N, Straussberg R, Mullikin JC, Teer JK, Geiger D, Kornitzer D, Bitterman-Deutsch O, Samson AO, Wakamiya M, Peterson JW, Kirtley ML, Pinchuk IV, Baze WB, Gahl WA, Kleta R, Anikster Y, Chopra AK. Phospholipase A2-activating protein is associated with a novel form of leukoencephalopathy. Brain 2016; 140:370-386. [PMID: 28007986 DOI: 10.1093/brain/aww295] [Citation(s) in RCA: 17] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/06/2016] [Revised: 09/27/2016] [Accepted: 09/28/2016] [Indexed: 12/14/2022] Open
Abstract
Leukoencephalopathies are a group of white matter disorders related to abnormal formation, maintenance, and turnover of myelin in the central nervous system. These disorders of the brain are categorized according to neuroradiological and pathophysiological criteria. Herein, we have identified a unique form of leukoencephalopathy in seven patients presenting at ages 2 to 4 months with progressive microcephaly, spastic quadriparesis, and global developmental delay. Clinical, metabolic, and imaging characterization of seven patients followed by homozygosity mapping and linkage analysis were performed. Next generation sequencing, bioinformatics, and segregation analyses followed, to determine a loss of function sequence variation in the phospholipase A2-activating protein encoding gene (PLAA). Expression and functional studies of the encoded protein were performed and included measurement of prostaglandin E2 and cytosolic phospholipase A2 activity in membrane fractions of fibroblasts derived from patients and healthy controls. Plaa-null mice were generated and prostaglandin E2 levels were measured in different tissues. The novel phenotype of our patients segregated with a homozygous loss-of-function sequence variant, causing the substitution of leucine at position 752 to phenylalanine, in PLAA, which causes disruption of the protein's ability to induce prostaglandin E2 and cytosolic phospholipase A2 synthesis in patients' fibroblasts. Plaa-null mice were perinatal lethal with reduced brain levels of prostaglandin E2 The non-functional phospholipase A2-activating protein and the associated neurological phenotype, reported herein for the first time, join other complex phospholipid defects that cause leukoencephalopathies in humans, emphasizing the importance of this axis in white matter development and maintenance.
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Affiliation(s)
- Tzipora C Falik Zaccai
- Institute of Human Genetics, Galilee Medical Center, Nahariya, Israel .,Faculty of Medicine in the Galilee, Bar Ilan University, Safed, Israel
| | - David Savitzki
- Pediatric Neurology Unit, Galilee Medical Center, Nahariya, Israel
| | | | - Thierry Vilboux
- Section on Human Biochemical Genetics, Medical Genetics Branch, National Human Genome Research Institute, National Institutes of Health, Bethesda, MD, USA.,Division of Medical Genomics, Inova Translational Medicine Institute, Inova Health System, Falls Church, VA, USA
| | - Eric C Fitts
- Department of Microbiology and Immunology, University of Texas Medical Branch, Galveston, TX, USA
| | - Yishay Shoval
- Institute of Human Genetics, Galilee Medical Center, Nahariya, Israel
| | - Limor Kalfon
- Institute of Human Genetics, Galilee Medical Center, Nahariya, Israel
| | - Nadra Samra
- Institute of Human Genetics, Galilee Medical Center, Nahariya, Israel
| | - Zohar Keren
- Institute of Human Genetics, Galilee Medical Center, Nahariya, Israel
| | - Bella Gross
- Faculty of Medicine in the Galilee, Bar Ilan University, Safed, Israel.,Department of Neurology, Galilee Medical Center, Nahariya, Israel
| | - Natalia Chasnyk
- Institute of Human Genetics, Galilee Medical Center, Nahariya, Israel
| | - Rachel Straussberg
- Pediatric Neurology Unit, Schneider Children's Medical Center, Petach Tikva, Israel.,Sackler School of Medicine, Tel Aviv University, Tel Aviv, Israel
| | - James C Mullikin
- Comparative Genomics Analysis Unit, National Human Genome Research Institute, National Institutes of Health, Bethesda, MD, USA.,NIH Intramural Sequencing Center, National Human Genome Research Institute, Rockville, MD, USA
| | - Jamie K Teer
- Department of Biostatistics and Bioinformatics, H. Lee Moffitt Cancer Center, Tampa, FL, USA
| | - Dan Geiger
- Computer Sciences, Technion - Israel Institute of Technology, Haifa, Israel
| | - Daniel Kornitzer
- Faculty of Medicine, Technion - I.I.T. and Rappaport Institute for Biomedical Research, Haifa, Israel
| | - Ora Bitterman-Deutsch
- Faculty of Medicine in the Galilee, Bar Ilan University, Safed, Israel.,Dermatology Clinic, Galilee Medical Center, Nahariya, Israel
| | - Abraham O Samson
- Faculty of Medicine in the Galilee, Bar Ilan University, Safed, Israel
| | - Maki Wakamiya
- Transgenic Mouse Core Facility, Institute for Translational Sciences and Animal Resource Center, University of Texas Medical Branch, Galveston, TX, USA
| | - Johnny W Peterson
- Department of Microbiology and Immunology, University of Texas Medical Branch, Galveston, TX, USA
| | - Michelle L Kirtley
- Department of Microbiology and Immunology, University of Texas Medical Branch, Galveston, TX, USA
| | - Iryna V Pinchuk
- Department of Internal Medicine, University of Texas Medical Branch, Galveston, TX, USA
| | - Wallace B Baze
- Department of Veterinary Sciences, MD Anderson Cancer Center, Bastrop, TX, USA
| | - William A Gahl
- Section on Human Biochemical Genetics, Medical Genetics Branch, National Human Genome Research Institute, National Institutes of Health, Bethesda, MD, USA
| | - Robert Kleta
- University College, Royal Free Hospital / UCL Medical School, London, UK
| | - Yair Anikster
- Sackler School of Medicine, Tel Aviv University, Tel Aviv, Israel.,Metabolic Disease Unit, Edmond and Lily Safra Children's Hospital, Sheba Medical Center, Tel Aviv, Israel
| | - Ashok K Chopra
- Department of Microbiology and Immunology, University of Texas Medical Branch, Galveston, TX, USA
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41
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Zukić S, Sinanović O, Mujagić S, Zonić L, Kovačević L. Megalencephalic leukoencephalopathy with subcortical cysts. Acta Neurol Belg 2016; 116:645-646. [PMID: 27015955 DOI: 10.1007/s13760-016-0629-y] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/11/2016] [Accepted: 03/10/2016] [Indexed: 11/25/2022]
Affiliation(s)
- Sanela Zukić
- Department of Neurology, University Clinical Center Tuzla, Trnovac bb, 75000, Tuzla, Bosnia and Herzegovina.
| | - Osman Sinanović
- Department of Neurology, University Clinical Center Tuzla, Trnovac bb, 75000, Tuzla, Bosnia and Herzegovina
| | - Svjetlana Mujagić
- Department of Radiology, University Clinical Center Tuzla, Trnovac bb, 75000, Tuzla, Bosnia and Herzegovina
| | - Lejla Zonić
- Department of Neurology, University Clinical Center Tuzla, Trnovac bb, 75000, Tuzla, Bosnia and Herzegovina
| | - Larisa Kovačević
- Department of Neurology, University Clinical Center Tuzla, Trnovac bb, 75000, Tuzla, Bosnia and Herzegovina
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Abdel-Salam GMH, Abdel-Hamid MS, Ismail SI, Hosny H, Omar T, Effat L, Aglan MS, Temtamy SA, Zaki MS. Megalencephalic leukoencephalopathy with cysts in twelve Egyptian patients: novel mutations in MLC1 and HEPACAM and a founder effect. Metab Brain Dis 2016; 31:1171-9. [PMID: 27389245 DOI: 10.1007/s11011-016-9861-7] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 04/26/2016] [Accepted: 06/19/2016] [Indexed: 11/25/2022]
Abstract
Two genes causing megalencephalic leukoencephalopathy with subcortical cysts (MLC) have been discovered so far. Here, we identified MLC1 and HEPACAM mutations in ten and two patients, respectively. The molecular results included an unreported inframe duplication mutation (c.929_930dupCTGCTG; p.L309dup) of MLC1 and a novel missense mutation c.293G>A (p.R98H) of HEPACAM. Further, the previously reported missense (c.278C>T; p.S93L) and the deletion/insertion (c.908_918delinsGCA; p.V303Gfs*96) were found in one and 8 patients (75 %), respectively. The 8 patients carrying the p.V303Gfs*96 shared a similar haplotype suggesting a founder effect. All mutations were in the homozygous state proving the autosomal recessive mode of inheritance. The core phenotype of macrocephaly, subcortical cysts and white matter appeared homogeneous although the patients differed in the onset, clinical course, disease severity and brain imaging findings. Our study expands the spectrum of mutations in MLC1 and HEPACAM and supports the genetic and clinical heterogeneity. Further, It confirms c.908_918delinsGCA (p.V303Gfs*96) as a founder mutation among Egyptian patients. This finding will contribute to provide targeted testing for this mutation in MLC patients in our population.
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Affiliation(s)
- Ghada M H Abdel-Salam
- Clinical Genetics Department, Human Genetics and Genome Research Division, National Research Centre, Tahrir street, Dokki, Cairo, Egypt.
- Centre of Excellence for Human Genetics, National Research Centre, Cairo, Egypt.
| | - Mohamed S Abdel-Hamid
- Centre of Excellence for Human Genetics, National Research Centre, Cairo, Egypt
- Medical Molecular Genetics Department, Human Genetics and Genome Research Division, National Research Centre, Cairo, Egypt
| | - Samira I Ismail
- Clinical Genetics Department, Human Genetics and Genome Research Division, National Research Centre, Tahrir street, Dokki, Cairo, Egypt
- Centre of Excellence for Human Genetics, National Research Centre, Cairo, Egypt
| | - Heba Hosny
- National Institute of Neuromotor system, Cairo, Egypt
| | - Tarek Omar
- Department of Pediatrics, Alexandria University, Alexandria, Egypt
| | - Laila Effat
- Centre of Excellence for Human Genetics, National Research Centre, Cairo, Egypt
- Medical Molecular Genetics Department, Human Genetics and Genome Research Division, National Research Centre, Cairo, Egypt
| | - Mona S Aglan
- Clinical Genetics Department, Human Genetics and Genome Research Division, National Research Centre, Tahrir street, Dokki, Cairo, Egypt
- Centre of Excellence for Human Genetics, National Research Centre, Cairo, Egypt
| | - Samia A Temtamy
- Clinical Genetics Department, Human Genetics and Genome Research Division, National Research Centre, Tahrir street, Dokki, Cairo, Egypt
- Centre of Excellence for Human Genetics, National Research Centre, Cairo, Egypt
| | - Maha S Zaki
- Clinical Genetics Department, Human Genetics and Genome Research Division, National Research Centre, Tahrir street, Dokki, Cairo, Egypt
- Centre of Excellence for Human Genetics, National Research Centre, Cairo, Egypt
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Sharma A, Gupta M, Gupta N, Garg A. Van der Knaap Disease: Megalencephalic Leukoencephalopathy with Subcortical Cysts. SAUDI JOURNAL OF MEDICINE & MEDICAL SCIENCES 2016; 4:238-239. [PMID: 30787739 PMCID: PMC6298348 DOI: 10.4103/1658-631x.188256] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Indexed: 11/23/2022]
Affiliation(s)
- Ankush Sharma
- Department of Neurology, Maharishi Markandeshwar Institute of Medical Sciences and Research, Mullana (Ambala), Haryana, India
| | - Munish Gupta
- Department of Neurology, Maharishi Markandeshwar Institute of Medical Sciences and Research, Mullana (Ambala), Haryana, India
| | - Nitin Gupta
- Department of Neurology, Maharishi Markandeshwar Institute of Medical Sciences and Research, Mullana (Ambala), Haryana, India
| | - Akash Garg
- Department of Neurology, Maharishi Markandeshwar Institute of Medical Sciences and Research, Mullana (Ambala), Haryana, India
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44
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Valk J, Van Der Knaap M. Selective Vulnerability in Toxic Encephalopathies and Metabolic Disorders. ACTA ACUST UNITED AC 2016. [DOI: 10.1177/197140099600900620] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/15/2022]
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45
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Savoiardo M, Bruzzone M, D'Incerti L, Farina L, Grisoli M. Metabolic and Genetic Diseases of the Brain. ACTA ACUST UNITED AC 2016. [DOI: 10.1177/19714009990120s311] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/17/2022]
Affiliation(s)
- M. Savoiardo
- Department of Neuroradiology, Istituto Nazionale Neurologico “C. Besta”; Milano, Italy
| | - M.G. Bruzzone
- Department of Neuroradiology, Istituto Nazionale Neurologico “C. Besta”; Milano, Italy
| | - L. D'Incerti
- Department of Neuroradiology, Istituto Nazionale Neurologico “C. Besta”; Milano, Italy
| | - L. Farina
- Department of Neuroradiology, Istituto Nazionale Neurologico “C. Besta”; Milano, Italy
| | - M. Grisoli
- Department of Neuroradiology, Istituto Nazionale Neurologico “C. Besta”; Milano, Italy
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Cao B, Yan H, Guo M, Xie H, Wu Y, Gu Q, Xiao J, Shang J, Yang Y, Xiong H, Niu Z, Wu X, Jiang Y, Wang J. Ten Novel Mutations in Chinese Patients with Megalencephalic Leukoencephalopathy with Subcortical Cysts and a Long-Term Follow-Up Research. PLoS One 2016; 11:e0157258. [PMID: 27322623 PMCID: PMC4913951 DOI: 10.1371/journal.pone.0157258] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/22/2015] [Accepted: 05/26/2016] [Indexed: 11/21/2022] Open
Abstract
Objective Megalencephalic leukoencephalopathy with subcortical cysts (MLC, OMIM 604004) is a rare neurological deterioration disease. We aimed to clarify clinical and genetic features of Chinese MLC patients. Methods Clinical information and peripheral venous blood of 20 patients and their families were collected, Sanger-sequencing and Multiple Ligation-dependent Probe Amplification were performed to make genetic analysis. Splicing-site mutation was confirmed with RT-PCR. UPD was detected by haplotype analysis. Follow-up study was performed through telephone for 27 patients. Results Out of 20 patients, macrocephaly, classic MRI features, motor development delay and cognitive impairment were detected in 20(100%), 20(100%), 17(85%) and 4(20%) patients, respectively. 20(100%) were clinically diagnosed with MLC. 19(95%) were genetically diagnosed with 10 novel mutations in MLC1, MLC1 and GlialCAM mutations were identified in 15 and 4 patients, respectively. Deletion mutation from exon4 to exon9 and a homozygous point mutation due to maternal UPD of chromosome22 in MLC1 were found firstly. c.598-2A>C in MLC1 leads to the skip of exon8. c.772-1G>C in MLC1 accounting for 15.5%(9/58) alleles in Chinese patients might be a founder or a hot-spot mutation. Out of 27 patients in the follow-up study, head circumference was ranged from 56cm to 61cm in patients older than 5yeas old, with a median of 57cm. Motor development delay and cognitive impairment were detected in 22(81.5%) and 5(18.5%) patients, respectively. Motor and cognitive deterioration was found in 5 (18.5%) and 2 patients (7.4%), respectively. Improvements and MRI recovery were first found in Chinese patients. Rate of seizures (45.5%), transient motor retrogress (45.5%) and unconsciousness (13.6%) after head trauma was much higher than that after fever (18.2%, 9.1%, 0%, respectively). Significance It’s a clinical and genetic analysis and a follow-up study for largest sample of Chinese MLC patients, identifying 10 novel mutations, expanding mutation spectrums and discovering clinical features of Chinese MLC patients.
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Affiliation(s)
- Binbin Cao
- Department of Pediatrics, Peking University First Hospital, Beijing 100034, China
| | - Huifang Yan
- Department of Pediatrics, Peking University First Hospital, Beijing 100034, China
| | - Mangmang Guo
- Department of Pediatrics, Peking University First Hospital, Beijing 100034, China
- Department of Pediatrics, Beijing Tian Tan Hospital, Capital Medical University Beijing 100050, China
| | - Han Xie
- Department of Pediatrics, Peking University First Hospital, Beijing 100034, China
| | - Ye Wu
- Department of Pediatrics, Peking University First Hospital, Beijing 100034, China
| | - Qiang Gu
- Department of Pediatrics, Peking University First Hospital, Beijing 100034, China
| | - Jiangxi Xiao
- Department of Radiology, Peking University First Hospital, Beijing 100034, China
| | - Jing Shang
- Department of Pediatrics, Peking University First Hospital, Beijing 100034, China
- Department of Neurology, Shanxi Dayi Hospital, Taiyuan 030000, Shanxi Province, China
| | - Yanling Yang
- Department of Pediatrics, Peking University First Hospital, Beijing 100034, China
| | - Hui Xiong
- Department of Pediatrics, Peking University First Hospital, Beijing 100034, China
| | - Zhengping Niu
- Department of Neurology, First Hospital of Shanxi Medical University, Taiyuan 030001, Shanxi Province, China
| | - Xiru Wu
- Department of Pediatrics, Peking University First Hospital, Beijing 100034, China
| | - Yuwu Jiang
- Department of Pediatrics, Peking University First Hospital, Beijing 100034, China
- * E-mail: (YWJ); (JMW)
| | - Jingmin Wang
- Department of Pediatrics, Peking University First Hospital, Beijing 100034, China
- * E-mail: (YWJ); (JMW)
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Moussa DM, El Nekeidy AA, Abougabal AM, Omar TI, Saleh TR. The role of MRI and MRS in the diagnosis of non hydrocephalic macrocrania in infancy and early childhood. THE EGYPTIAN JOURNAL OF RADIOLOGY AND NUCLEAR MEDICINE 2016. [DOI: 10.1016/j.ejrnm.2015.09.009] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022] Open
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48
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Lanciotti A, Brignone MS, Visentin S, De Nuccio C, Catacuzzeno L, Mallozzi C, Petrini S, Caramia M, Veroni C, Minnone G, Bernardo A, Franciolini F, Pessia M, Bertini E, Petrucci TC, Ambrosini E. Megalencephalic leukoencephalopathy with subcortical cysts protein-1 regulates epidermal growth factor receptor signaling in astrocytes. Hum Mol Genet 2016; 25:1543-58. [DOI: 10.1093/hmg/ddw032] [Citation(s) in RCA: 26] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/22/2015] [Accepted: 02/03/2016] [Indexed: 01/13/2023] Open
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49
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Labauge P, Ayrignac X, Carra-Dallière C, Menjot de Champfleur N. Leucodistrofie dell’adulto. Neurologia 2016. [DOI: 10.1016/s1634-7072(15)76144-1] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/16/2022] Open
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50
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Dahmoush HM, Melhem ER, Vossough A. Metabolic, endocrine, and other genetic disorders. HANDBOOK OF CLINICAL NEUROLOGY 2016; 136:1221-1259. [PMID: 27430466 DOI: 10.1016/b978-0-444-53486-6.00063-6] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/06/2023]
Abstract
Metabolic, endocrine, and genetic diseases of the brain include a very large array of disorders caused by a wide range of underlying abnormalities and involving a variety of brain structures. Often these disorders manifest as recognizable, though sometimes overlapping, patterns on neuroimaging studies that may enable a diagnosis based on imaging or may alternatively provide enough clues to direct further diagnostic evaluation. The diagnostic workup can include various biochemical laboratory or genetic studies. In this chapter, after a brief review of normal white-matter development, we will describe a variety of leukodystrophies resulting from metabolic disorders involving the brain, including mitochondrial and respiratory chain diseases. We will then describe various acidurias, urea cycle disorders, disorders related to copper and iron metabolism, and disorders of ganglioside and mucopolysaccharide metabolism. Lastly, various other hypomyelinating and dysmyelinating leukodystrophies, including vanishing white-matter disease, megalencephalic leukoencephalopathy with subcortical cysts, and oculocerebrorenal syndrome will be presented. In the following section on endocrine disorders, we will examine various disorders of the hypothalamic-pituitary axis, including developmental, inflammatory, and neoplastic diseases. Neonatal hypoglycemia will also be briefly reviewed. In the final section, we will review a few of the common genetic phakomatoses. Throughout the text, both imaging and brief clinical features of the various disorders will be discussed.
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Affiliation(s)
- Hisham M Dahmoush
- Department of Radiology, Children's Hospital of Philadelphia and University of Pennsylvania, Philadelphia, PA, USA
| | - Elias R Melhem
- Department of Diagnostic Radiology and Nuclear Medicine, University of Maryland, Baltimore, MD, USA
| | - Arastoo Vossough
- Department of Radiology, Children's Hospital of Philadelphia and University of Pennsylvania, Philadelphia, PA, USA.
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