1
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Zhang D, Hua Z, Li Z. The role of glutamate and glutamine metabolism and related transporters in nerve cells. CNS Neurosci Ther 2024; 30:e14617. [PMID: 38358002 PMCID: PMC10867874 DOI: 10.1111/cns.14617] [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: 10/19/2023] [Revised: 12/15/2023] [Accepted: 01/10/2024] [Indexed: 02/16/2024] Open
Abstract
BACKGROUND Glutamate and glutamine are the most abundant amino acids in the blood and play a crucial role in cell survival in the nervous system. Various transporters found in cell and mitochondrial membranes, such as the solute carriers (SLCs) superfamily, are responsible for maintaining the balance of glutamate and glutamine in the synaptic cleft and within cells. This balance affects the metabolism of glutamate and glutamine as non-essential amino acids. AIMS This review aims to provide an overview of the transporters and enzymes associated with glutamate and glutamine in neuronal cells. DISCUSSION We delve into the function of glutamate and glutamine in the nervous system by discussing the transporters involved in the glutamate-glutamine cycle and the key enzymes responsible for their mutual conversion. Additionally, we highlight the role of glutamate and glutamine as carbon and nitrogen donors, as well as their significance as precursors for the synthesis of reduced glutathione (GSH). CONCLUSION Glutamate and glutamine play a crucial role in the brain due to their special effects. It is essential to focus on understanding glutamate and glutamine metabolism to comprehend the physiological behavior of nerve cells and to treat nervous system disorders and cancer.
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Affiliation(s)
- Dongyang Zhang
- Department of PediatricsShengjing Hospital of China Medical UniversityShenyangLiaoningChina
- Medical Research Center, Liaoning Key Laboratory of Research and Application of Animal Models for Environment and Metabolic DiseasesShengjing Hospital of China Medical UniversityShenyangLiaoningChina
| | - Zhongyan Hua
- Department of PediatricsShengjing Hospital of China Medical UniversityShenyangLiaoningChina
- Medical Research Center, Liaoning Key Laboratory of Research and Application of Animal Models for Environment and Metabolic DiseasesShengjing Hospital of China Medical UniversityShenyangLiaoningChina
| | - Zhijie Li
- Department of PediatricsShengjing Hospital of China Medical UniversityShenyangLiaoningChina
- Medical Research Center, Liaoning Key Laboratory of Research and Application of Animal Models for Environment and Metabolic DiseasesShengjing Hospital of China Medical UniversityShenyangLiaoningChina
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2
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Shevlyakov AD, Kolesnikova TO, de Abreu MS, Petersen EV, Yenkoyan KB, Demin KA, Kalueff AV. Forward Genetics-Based Approaches to Understanding the Systems Biology and Molecular Mechanisms of Epilepsy. Int J Mol Sci 2023; 24:ijms24065280. [PMID: 36982355 PMCID: PMC10049737 DOI: 10.3390/ijms24065280] [Citation(s) in RCA: 5] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/31/2022] [Revised: 02/28/2023] [Accepted: 03/03/2023] [Indexed: 03/12/2023] Open
Abstract
Epilepsy is a highly prevalent, severely debilitating neurological disorder characterized by seizures and neuronal hyperactivity due to an imbalanced neurotransmission. As genetic factors play a key role in epilepsy and its treatment, various genetic and genomic technologies continue to dissect the genetic causes of this disorder. However, the exact pathogenesis of epilepsy is not fully understood, necessitating further translational studies of this condition. Here, we applied a computational in silico approach to generate a comprehensive network of molecular pathways involved in epilepsy, based on known human candidate epilepsy genes and their established molecular interactors. Clustering the resulting network identified potential key interactors that may contribute to the development of epilepsy, and revealed functional molecular pathways associated with this disorder, including those related to neuronal hyperactivity, cytoskeletal and mitochondrial function, and metabolism. While traditional antiepileptic drugs often target single mechanisms associated with epilepsy, recent studies suggest targeting downstream pathways as an alternative efficient strategy. However, many potential downstream pathways have not yet been considered as promising targets for antiepileptic treatment. Our study calls for further research into the complexity of molecular mechanisms underlying epilepsy, aiming to develop more effective treatments targeting novel putative downstream pathways of this disorder.
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Affiliation(s)
- Anton D. Shevlyakov
- Graduate Program in Bioinformatics and Genomics, Sirius University of Science and Technology, 354340 Sochi, Russia
- Neuroscience Program, Sirius University of Science and Technology, 354340 Sochi, Russia
| | | | | | | | - Konstantin B. Yenkoyan
- Neuroscience Laboratory of COBRAIN Center for Fundamental Brain Research, and Biochemistry Department, Yerevan State Medical University named after M. Heratsi, Yerevan 0025, Armenia
| | - Konstantin A. Demin
- Institute of Translational Biomedicine, St. Petersburg State University, 199034 St. Petersburg, Russia
- Institute of Experimental Medicine, Almazov National Medical Research Centre, Ministry of Healthcare of Russian Federation, 194021 St. Petersburg, Russia
- Correspondence: (K.A.D.); (A.V.K.); Tel.: +7-240-899-9571 (A.V.K.)
| | - Allan V. Kalueff
- Neuroscience Program, Sirius University of Science and Technology, 354340 Sochi, Russia
- Neuroscience Laboratory of COBRAIN Center for Fundamental Brain Research, and Biochemistry Department, Yerevan State Medical University named after M. Heratsi, Yerevan 0025, Armenia
- Institute of Translational Biomedicine, St. Petersburg State University, 199034 St. Petersburg, Russia
- Institute of Experimental Medicine, Almazov National Medical Research Centre, Ministry of Healthcare of Russian Federation, 194021 St. Petersburg, Russia
- Laboratory of Preclinical Bioscreening, Granov Russian Research Center of Radiology and Surgical Technologies, Ministry of Healthcare of Russian Federation, 197758 Pesochny, Russia
- Neuroscience Group, Ural Federal University, 620002 Ekaterinburg, Russia
- Laboratory of Biopsychiatry, Scientific Research Institute of Physiology and Basic Medicine, 630117 Novosibirsk, Russia
- Correspondence: (K.A.D.); (A.V.K.); Tel.: +7-240-899-9571 (A.V.K.)
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3
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Gan Y, Wei Z, Liu C, Li G, Feng Y, Deng Y. Solute carrier transporter disease and developmental and epileptic encephalopathy. Front Neurol 2022; 13:1013903. [PMID: 36419532 PMCID: PMC9676364 DOI: 10.3389/fneur.2022.1013903] [Citation(s) in RCA: 4] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/08/2022] [Accepted: 09/07/2022] [Indexed: 09/14/2023] Open
Abstract
The International League Against Epilepsy officially revised its classification in 2017, which amended "epileptic encephalopathy" to "developmental and epileptic encephalopathy". With the development of genetic testing technology, an increasing number of genes that cause developmental and epileptic encephalopathies are being identified. Among these, solute transporter dysfunction is part of the etiology of developmental and epileptic encephalopathies. Solute carrier transporters play an essential physiological function in the human body, and their dysfunction is associated with various human diseases. Therefore, in-depth studies of developmental and epileptic encephalopathies caused by solute carrier transporter dysfunction can help develop new therapeutic modalities to facilitate the treatment of refractory epilepsy and improve patient prognosis. In this article, the concept of transporter protein disorders is first proposed, and nine developmental and epileptic encephalopathies caused by solute carrier transporter dysfunction are described in detail in terms of pathogenesis, clinical manifestations, ancillary tests, and precise treatment to provide ideas for the precise treatment of epilepsy.
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Affiliation(s)
- Yajing Gan
- Department of Neurology, Epilepsy Center of Xijing Hospital, Fourth Military Medical University, Xi'an, China
| | - Zihan Wei
- Department of Neurology, Epilepsy Center of Xijing Hospital, Fourth Military Medical University, Xi'an, China
| | - Chao Liu
- Department of Neurology, Epilepsy Center of Xijing Hospital, Fourth Military Medical University, Xi'an, China
| | - Guoyan Li
- Department of Neurology, Epilepsy Center of Xijing Hospital, Fourth Military Medical University, Xi'an, China
| | - Yan Feng
- Department of Neurology, Epilepsy Center of Xijing Hospital, Fourth Military Medical University, Xi'an, China
| | - Yanchun Deng
- Department of Neurology, Epilepsy Center of Xijing Hospital, Fourth Military Medical University, Xi'an, China
- Xijing Institute of Epilepsy and Encephalopathy, Xi'an, China
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4
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Monné M, Marobbio CMT, Agrimi G, Palmieri L, Palmieri F. Mitochondrial transport and metabolism of the major methyl donor and versatile cofactor S-adenosylmethionine, and related diseases: A review †. IUBMB Life 2022; 74:573-591. [PMID: 35730628 DOI: 10.1002/iub.2658] [Citation(s) in RCA: 8] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/04/2022] [Accepted: 05/19/2022] [Indexed: 11/08/2022]
Abstract
S-adenosyl-L-methionine (SAM) is a coenzyme and the most commonly used methyl-group donor for the modification of metabolites, DNA, RNA and proteins. SAM biosynthesis and SAM regeneration from the methylation reaction product S-adenosyl-L-homocysteine (SAH) take place in the cytoplasm. Therefore, the intramitochondrial SAM-dependent methyltransferases require the import of SAM and export of SAH for recycling. Orthologous mitochondrial transporters belonging to the mitochondrial carrier family have been identified to catalyze this antiport transport step: Sam5p in yeast, SLC25A26 (SAMC) in humans, and SAMC1-2 in plants. In mitochondria SAM is used by a vast number of enzymes implicated in the following processes: the regulation of replication, transcription, translation, and enzymatic activities; the maturation and assembly of mitochondrial tRNAs, ribosomes and protein complexes; and the biosynthesis of cofactors, such as ubiquinone, lipoate, and molybdopterin. Mutations in SLC25A26 and mitochondrial SAM-dependent enzymes have been found to cause human diseases, which emphasizes the physiological importance of these proteins.
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Affiliation(s)
- Magnus Monné
- Department of Biosciences, Biotechnologies and Biopharmaceutics, University of Bari, Bari, Italy.,Department of Sciences, University of Basilicata, Potenza, Italy
| | - Carlo M T Marobbio
- Department of Biosciences, Biotechnologies and Biopharmaceutics, University of Bari, Bari, Italy
| | - Gennaro Agrimi
- Department of Biosciences, Biotechnologies and Biopharmaceutics, University of Bari, Bari, Italy
| | - Luigi Palmieri
- Department of Biosciences, Biotechnologies and Biopharmaceutics, University of Bari, Bari, Italy.,CNR Institute of Biomembranes, Bioenergetics and Molecular Biotechnologies (IBIOM), Bari, Italy
| | - Ferdinando Palmieri
- Department of Biosciences, Biotechnologies and Biopharmaceutics, University of Bari, Bari, Italy.,CNR Institute of Biomembranes, Bioenergetics and Molecular Biotechnologies (IBIOM), Bari, Italy
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5
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Miniero DV, Monné M, Di Noia MA, Palmieri L, Palmieri F. Evidence for Non-Essential Salt Bridges in the M-Gates of Mitochondrial Carrier Proteins. Int J Mol Sci 2022; 23:ijms23095060. [PMID: 35563451 PMCID: PMC9104175 DOI: 10.3390/ijms23095060] [Citation(s) in RCA: 4] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/28/2022] [Revised: 04/28/2022] [Accepted: 04/29/2022] [Indexed: 01/05/2023] Open
Abstract
Mitochondrial carriers, which transport metabolites, nucleotides, and cofactors across the mitochondrial inner membrane, have six transmembrane α-helices enclosing a translocation pore with a central substrate binding site whose access is controlled by a cytoplasmic and a matrix gate (M-gate). The salt bridges formed by the three PX[DE]XX[RK] motifs located on the odd-numbered transmembrane α-helices greatly contribute to closing the M-gate. We have measured the transport rates of cysteine mutants of the charged residue positions in the PX[DE]XX[RK] motifs of the bovine oxoglutarate carrier, the yeast GTP/GDP carrier, and the yeast NAD+ transporter, which all lack one of these charged residues. Most single substitutions, including those of the non-charged and unpaired charged residues, completely inactivated transport. Double mutations of charged pairs showed that all three carriers contain salt bridges non-essential for activity. Two double substitutions of these non-essential charge pairs exhibited higher transport rates than their corresponding single mutants, whereas swapping the charged residues in these positions did not increase activity. The results demonstrate that some of the residues in the charged residue positions of the PX[DE]XX[KR] motifs are important for reasons other than forming salt bridges, probably for playing specific roles related to the substrate interaction-mediated conformational changes leading to the M-gate opening/closing.
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Affiliation(s)
- Daniela Valeria Miniero
- Department of Biosciences, Biotechnologies and Biopharmaceutics, University of Bari, Via E. Orabona 4, 70125 Bari, Italy; (D.V.M.); (M.M.); (M.A.D.N.)
| | - Magnus Monné
- Department of Biosciences, Biotechnologies and Biopharmaceutics, University of Bari, Via E. Orabona 4, 70125 Bari, Italy; (D.V.M.); (M.M.); (M.A.D.N.)
- Department of Sciences, University of Basilicata, Via Ateneo Lucano 10, 85100 Potenza, Italy
| | - Maria Antonietta Di Noia
- Department of Biosciences, Biotechnologies and Biopharmaceutics, University of Bari, Via E. Orabona 4, 70125 Bari, Italy; (D.V.M.); (M.M.); (M.A.D.N.)
| | - Luigi Palmieri
- Department of Biosciences, Biotechnologies and Biopharmaceutics, University of Bari, Via E. Orabona 4, 70125 Bari, Italy; (D.V.M.); (M.M.); (M.A.D.N.)
- CNR Institute of Biomembranes, Bioenergetics and Molecular Biotechnologies (IBIOM), 70126 Bari, Italy
- Correspondence: (L.P.); (F.P.)
| | - Ferdinando Palmieri
- Department of Biosciences, Biotechnologies and Biopharmaceutics, University of Bari, Via E. Orabona 4, 70125 Bari, Italy; (D.V.M.); (M.M.); (M.A.D.N.)
- CNR Institute of Biomembranes, Bioenergetics and Molecular Biotechnologies (IBIOM), 70126 Bari, Italy
- Correspondence: (L.P.); (F.P.)
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6
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Song J, Yang X, Zhang M, Wang C, Chen L. Glutamate Metabolism in Mitochondria is Closely Related to Alzheimer's Disease. J Alzheimers Dis 2021; 84:557-578. [PMID: 34602474 DOI: 10.3233/jad-210595] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/23/2022]
Abstract
Glutamate is the main excitatory neurotransmitter in the brain, and its excitatory neurotoxicity is closely related to the occurrence and development of Alzheimer's disease. However, increasing evidence shows that in the process of Alzheimer's disease, glutamate is not only limited to its excitotoxicity as a neurotransmitter but also related to the disorder of its metabolic balance. The balance of glutamate metabolism in the brain is an important determinant of central nervous system health, and the maintenance of this balance is closely related to glutamate uptake, glutamate circulation, intracellular mitochondrial transport, and mitochondrial metabolism. In this paper, we intend to elaborate the key role of mitochondrial glutamate metabolism in the pathogenesis of Alzheimer's disease and review glutamate metabolism in mitochondria as a potential target in the treatment of Alzheimer's disease.
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Affiliation(s)
- Jiayi Song
- Department of Pharmacology, Basic College of Medicine, Jilin University, Changchun, People's Republic of China.,Cadre's Ward, The First Hospital of Jilin University, Changchun, People's Republic of China
| | - Xuehan Yang
- Department of Pharmacology, Basic College of Medicine, Jilin University, Changchun, People's Republic of China
| | - Ming Zhang
- Department of Pharmacology, Basic College of Medicine, Jilin University, Changchun, People's Republic of China
| | - Chunyan Wang
- Cadre's Ward, The First Hospital of Jilin University, Changchun, People's Republic of China
| | - Li Chen
- Department of Pharmacology, Basic College of Medicine, Jilin University, Changchun, People's Republic of China
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7
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New avenues in molecular genetics for the diagnosis and application of therapeutics to the epilepsies. Epilepsy Behav 2021; 121:106428. [PMID: 31400936 DOI: 10.1016/j.yebeh.2019.07.029] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 05/05/2019] [Revised: 06/14/2019] [Accepted: 07/06/2019] [Indexed: 11/22/2022]
Abstract
Genetic epidemiology studies have shown that most epilepsies involve some genetic cause. In addition, twin studies have helped strengthen the hypothesis that in most patients with epilepsy, a complex inheritance is involved. More recently, with the development of high-density single-nucleotide polymorphism (SNP) microarrays and next-generation sequencing (NGS) technologies, the discovery of genes related to the epilepsies has accelerated tremendously. Especially, the use of whole exome sequencing (WES) has had a considerable impact on the identification of rare genetic variants with large effect sizes, including inherited or de novo mutations in severe forms of childhood epilepsies. The identification of pathogenic variants in patients with these childhood epilepsies provides many benefits for patients and families, such as the confirmation of the genetic nature of the diseases. This process will allow for better genetic counseling, more accurate therapy decisions, and a significant positive emotional impact. However, to study the genetic component of the more common forms of epilepsy, the use of high-density SNP arrays in genome-wide association studies (GWAS) seems to be the strategy of choice. As such, researchers can identify loci containing genetic variants associated with the common forms of epilepsy. The knowledge generated over the past two decades about the effects of the mutations that cause the monogenic epilepsy is tremendous; however, the scientific community is just starting to apply this information in order to generate better target treatments.
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8
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Kunji ERS, King MS, Ruprecht JJ, Thangaratnarajah C. The SLC25 Carrier Family: Important Transport Proteins in Mitochondrial Physiology and Pathology. Physiology (Bethesda) 2021; 35:302-327. [PMID: 32783608 PMCID: PMC7611780 DOI: 10.1152/physiol.00009.2020] [Citation(s) in RCA: 77] [Impact Index Per Article: 25.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/17/2022] Open
Abstract
Members of the mitochondrial carrier family (SLC25) transport a variety of compounds across the inner membrane of mitochondria. These transport steps provide building blocks for the cell and link the pathways of the mitochondrial matrix and cytosol. An increasing number of diseases and pathologies has been associated with their dysfunction. In this review, the molecular basis of these diseases is explained based on our current understanding of their transport mechanism.
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Affiliation(s)
- Edmund R S Kunji
- Medical Research Council Mitochondrial Biology Unit, University of Cambridge, Cambridge, United Kingdom
| | - Martin S King
- Medical Research Council Mitochondrial Biology Unit, University of Cambridge, Cambridge, United Kingdom
| | - Jonathan J Ruprecht
- Medical Research Council Mitochondrial Biology Unit, University of Cambridge, Cambridge, United Kingdom
| | - Chancievan Thangaratnarajah
- Groningen Biomolecular Sciences and Biotechnology Institute, Membrane Enzymology, University of Groningen, Groningen, The Netherlands
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9
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Pasquadibisceglie A, Polticelli F. Computational studies of the mitochondrial carrier family SLC25. Present status and future perspectives. BIO-ALGORITHMS AND MED-SYSTEMS 2021. [DOI: 10.1515/bams-2021-0018] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/04/2023]
Abstract
Abstract
The members of the mitochondrial carrier family, also known as solute carrier family 25 (SLC25), are transmembrane proteins involved in the translocation of a plethora of small molecules between the mitochondrial intermembrane space and the matrix. These transporters are characterized by three homologous domains structure and a transport mechanism that involves the transition between different conformations. Mutations in regions critical for these transporters’ function often cause several diseases, given the crucial role of these proteins in the mitochondrial homeostasis. Experimental studies can be problematic in the case of membrane proteins, in particular concerning the characterization of the structure–function relationships. For this reason, computational methods are often applied in order to develop new hypotheses or to support/explain experimental evidence. Here the computational analyses carried out on the SLC25 members are reviewed, describing the main techniques used and the outcome in terms of improved knowledge of the transport mechanism. Potential future applications on this protein family of more recent and advanced in silico methods are also suggested.
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Affiliation(s)
| | - Fabio Polticelli
- Department of Sciences , Roma Tre University , Rome , Italy
- National Institute of Nuclear Physics, Roma Tre Section , Rome , Italy
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10
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Patanè F, Pasquetti E, Sullo F, Tosto M, Sciuto L, Garozzo MT, Praticò ER, Falsaperla R. SLC25A22 and Its Related Epileptic Encephalopathies. JOURNAL OF PEDIATRIC NEUROLOGY 2021. [DOI: 10.1055/s-0041-1728685] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/21/2022]
Abstract
AbstractEpileptic encephalopathy is a condition in which seizures, electroencephalographic epileptiform abnormalities lead to a progressive deterioration of brain functions causing a significant psychomotor delay. One of the typical features of this heterogeneous and large group of severe disorders is the extremely early onset of seizures. The main causes of the epileptic encephalopathies include structural brain defects, inherited metabolic disorders; in this aspect, more than 100 genetic defects, including mutations in the solute carrier family 25 (SLC25A22) gene which encodes a mitochondrial glutamate carrier. To date, the main clinical phenotypes related to mutations of this gene are Ohtahara syndrome (or early infantile epileptic encephalopathy), early myoclonic encephalopathy and migrating partial seizures in infancy. In all the cases, prognosis is poor and no disease-modifying treatment is available in the present days.
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Affiliation(s)
- Francesca Patanè
- Pediatrics Postgraduate Residency Program, Section of Pediatrics and Child Neuropsychiatry, Department of Clinical and Experimental Medicine, University of Catania, Catania, Italy
| | - Elisa Pasquetti
- Pediatrics Postgraduate Residency Program, Section of Pediatrics and Child Neuropsychiatry, Department of Clinical and Experimental Medicine, University of Catania, Catania, Italy
| | - Federica Sullo
- Pediatrics Postgraduate Residency Program, Section of Pediatrics and Child Neuropsychiatry, Department of Clinical and Experimental Medicine, University of Catania, Catania, Italy
| | - Monica Tosto
- Pediatrics Postgraduate Residency Program, Section of Pediatrics and Child Neuropsychiatry, Department of Clinical and Experimental Medicine, University of Catania, Catania, Italy
| | - Laura Sciuto
- Pediatrics Postgraduate Residency Program, Section of Pediatrics and Child Neuropsychiatry, Department of Clinical and Experimental Medicine, University of Catania, Catania, Italy
| | - Maria Teresa Garozzo
- Unit of Pediatric and Pediatric Emergency, Hospital “Cannizzaro,” Catania, Italy
| | | | - Raffaele Falsaperla
- Unit of Pediatrics and Pediatric Emergency, University Hospital “Policlinico Rodolico-San Marco,” Catania, Italy
- Unit of Neonatal Intensive Care and Neonatology, University Hospital “Policlinico Rodolico-San Marco,” Catania, Italy
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11
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Nicotera AG, Dicanio D, Pironti E, Bonsignore M, Cafeo A, Efthymiou S, Mondello P, Salpietro V, Houlden H, Di Rosa G. De novo mutation in SLC25A22 gene: expansion of the clinical and electroencephalographic phenotype. J Neurogenet 2021; 35:67-73. [PMID: 33821742 DOI: 10.1080/01677063.2021.1892094] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/13/2022]
Abstract
The SLC25A22 (Solute Carrier Family 25, Member 22) gene encodes for a mitochondrial glutamate/H+ symporter and is involved in the mitochondrial transport of metabolites across the mitochondrial membrane. We hereby report a 12-year-old girl presenting with early-onset epileptic encephalopathy, hypotonia, and global developmental delay. Whole exome sequencing identified a novel homozygous missense mutation in SLC25A22 gene (c.97A>G; p.Lys33Glu), as the likely cause of the disease. The phenotype of our patient and EEG recordings do not completely overlap with the phenotypes previously described, leading to a new and more complex form of disease associated with SLC25A22 variants, characterized by dyskinetic movements and oculogyric crisis.
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Affiliation(s)
- Antonio Gennaro Nicotera
- Department of Human Pathology of the Adult and Developmental Age "Gaetano Barresi", Unit of Child Neurology and Psychiatry, University of Messina, Messina, Italy
| | - Daniela Dicanio
- Department of Human Pathology of the Adult and Developmental Age "Gaetano Barresi", Unit of Child Neurology and Psychiatry, University of Messina, Messina, Italy
| | - Erica Pironti
- Department of Human Pathology of the Adult and Developmental Age "Gaetano Barresi", Unit of Child Neurology and Psychiatry, University of Messina, Messina, Italy
| | - Maria Bonsignore
- Department of Human Pathology of the Adult and Developmental Age "Gaetano Barresi", Unit of Child Neurology and Psychiatry, University of Messina, Messina, Italy
| | - Anna Cafeo
- Department of Human Pathology of the Adult and Developmental Age "Gaetano Barresi", Unit of Child Neurology and Psychiatry, University of Messina, Messina, Italy
| | - Stephanie Efthymiou
- Department of Neuromuscular Disorders, Institute of Neurology, University College London, London, UK
| | - Patrizia Mondello
- Division of Hematology, Department of Human Pathology in Adulthood and Childhood "Gaetano Barresi", University of Messina, Messina, Italy
| | - Vincenzo Salpietro
- Department of Neuromuscular Disorders, Institute of Neurology, University College London, London, UK
| | - Henry Houlden
- Department of Neuromuscular Disorders, Institute of Neurology, University College London, London, UK
| | - Gabriella Di Rosa
- Department of Human Pathology of the Adult and Developmental Age "Gaetano Barresi", Unit of Child Neurology and Psychiatry, University of Messina, Messina, Italy
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12
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El Halabi T, Dirani M, Hotait M, Nasreddine W, Beydoun A. A novel possible familial cause of epilepsy of infancy with migrating focal seizures related to SZT2 gene variant. Epilepsia Open 2021; 6:73-78. [PMID: 33681650 PMCID: PMC7918305 DOI: 10.1002/epi4.12451] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/31/2020] [Revised: 11/10/2020] [Accepted: 11/22/2020] [Indexed: 12/31/2022] Open
Abstract
Seizure threshold-2 (SZT2) gene variants have been associated with a decrease in seizure threshold resulting in variable phenotypic expressions ranging from mild-moderate intellectual disabilities without seizures, to an early-onset epileptic encephalopathy with severe cognitive impairment. In addition, hypotonia and distinctive facial dysmorphism, including a high forehead and to a lesser extent ptosis and down-slanting palpebral fissures, were present in the majority. We herein report a novel SZT2 variant in one of two siblings both diagnosed with epilepsy of infancy with migrating focal seizures (EIMFS). This report is the fourth to document a possible familial case in EIMFS, a condition that was not previously associated with SZT2 variant. This report expands the phenotypic expression of SZT2, corroborates the importance of genetic counseling in some cases of EIMFS, and highlights the efficacy of potassium bromide in controlling the seizures associated with this condition.
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Affiliation(s)
- Tarek El Halabi
- Neurology DepartmentAmerican University of Beirut Medical CenterBeirutLebanon
| | - Maya Dirani
- Neurology DepartmentAmerican University of Beirut Medical CenterBeirutLebanon
| | - Mostafa Hotait
- Neurology DepartmentAmerican University of Beirut Medical CenterBeirutLebanon
| | - Wassim Nasreddine
- Neurology DepartmentAmerican University of Beirut Medical CenterBeirutLebanon
| | - Ahmad Beydoun
- Neurology DepartmentAmerican University of Beirut Medical CenterBeirutLebanon
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13
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Mastrangelo M. Epilepsy in inherited neurotransmitter disorders: Spotlights on pathophysiology and clinical management. Metab Brain Dis 2021; 36:29-43. [PMID: 33095372 DOI: 10.1007/s11011-020-00635-x] [Citation(s) in RCA: 6] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 04/23/2020] [Accepted: 10/16/2020] [Indexed: 01/02/2023]
Abstract
Inborn errors of neurotransmitter metabolism are ultrarare disorders affecting neurotransmitter biosynthesis, breakdown or transport or their essential cofactors. Neurotransmitter dysfunctions could also result from the impairment of neuronal receptors, intracellular signaling, vesicle release or other synaptic abnormalities. Epilepsy is the main clinical hallmark in some of these diseases (e.g. disorders of GABA metabolism, glycine encephalopathy) while it is infrequent in others (e.g. all the disorders of monoamine metabolism in exception for dihydropteridine reductase deficiency). This review analyzes the epileptogenic mechanisms, the epilepsy phenotypes and the principle for the clinical management of epilepsy in primary and secondary inherited disorders of neurotransmitter metabolism (disorders of GABA, serine and glycine metabolism, disorders of neurotransmitter receptors and secondary neurotransmitter diseases).
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Affiliation(s)
- Mario Mastrangelo
- Child Neurology and Psychiatry Unit-Department of Human Neuroscience, Sapienza Università di Roma-Umberto I Policlinico di Roma, Via dei Sabelli, 108 - 00141, Roma, Italy.
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14
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André MV, Cacciagli P, Cano A, Vaugier L, Roussel M, Girard N, Chabrol B, Villard L, Milh M. The phenotype caused by recessive variations in SLC25A22: Report of a new case and literature review. Arch Pediatr 2020; 28:87-92. [PMID: 33342683 DOI: 10.1016/j.arcped.2020.10.015] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/25/2018] [Revised: 07/20/2020] [Accepted: 10/31/2020] [Indexed: 10/22/2022]
Abstract
We describe the clinical, electroencephalography (EEG), and developmental features of a patient with developmental and epileptic encephalopathy due to a homozygous pathogenic variation of mitochondrial glutamate/H+ symporter SLC25A22. Epilepsy began during the first week of life with focal onset seizures. Interictal EEG revealed a suppression-burst pattern with extensive periods of non-activity. The prospective follow-up confirmed developmental encephalopathy as well as ongoing active epilepsy and almost no sign of development at 8 years of age. We confirm in the following paper that SLC25A22 recessive variations may cause a severe developmental and epileptic encephalopathy characterized by a suppression-burst pattern. On the basis of an in-depth literature review, we also provide an overview of this rare genetic cause of neonatal onset epilepsy.
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Affiliation(s)
- M-V André
- Department of pediatric neurology, hôpital de la Timone, AP-HM, 13085 Marseille, France.
| | - P Cacciagli
- Inserm, GMGF, UMR_S 910, faculté de médecine, Aix-Marseille university, 13085 Marseille, France; Department of medical genetics, hôpital de La Timone, AP-HM, 13085 Marseille, France
| | - A Cano
- Department of pediatric neurology, hôpital de la Timone, AP-HM, 13085 Marseille, France
| | - L Vaugier
- Department of clinical neurophysiology, hôpital de la Timone, AP-HM, 13085 Marseille, France
| | - M Roussel
- Department of clinical neurophysiologie, hôpital Nord, AP-HM, 13015 Marseille, France
| | - N Girard
- Department of Neuroradiology, Aix-Marseille University, AP-HM, 13085 Marseille, France
| | - B Chabrol
- Department of pediatric neurology, hôpital de la Timone, AP-HM, 13085 Marseille, France
| | - L Villard
- Inserm, GMGF, UMR_S 910, faculté de médecine, Aix-Marseille university, 13085 Marseille, France; Department of medical genetics, hôpital de La Timone, AP-HM, 13085 Marseille, France
| | - M Milh
- Department of pediatric neurology, hôpital de la Timone, AP-HM, 13085 Marseille, France; Inserm, GMGF, UMR_S 910, faculté de médecine, Aix-Marseille university, 13085 Marseille, France
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15
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Russo GL, Sonsalla G, Natarajan P, Breunig CT, Bulli G, Merl-Pham J, Schmitt S, Giehrl-Schwab J, Giesert F, Jastroch M, Zischka H, Wurst W, Stricker SH, Hauck SM, Masserdotti G, Götz M. CRISPR-Mediated Induction of Neuron-Enriched Mitochondrial Proteins Boosts Direct Glia-to-Neuron Conversion. Cell Stem Cell 2020; 28:524-534.e7. [PMID: 33202244 PMCID: PMC7939544 DOI: 10.1016/j.stem.2020.10.015] [Citation(s) in RCA: 38] [Impact Index Per Article: 9.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/05/2019] [Revised: 08/11/2020] [Accepted: 08/20/2020] [Indexed: 12/17/2022]
Abstract
Astrocyte-to-neuron conversion is a promising avenue for neuronal replacement therapy. Neurons are particularly dependent on mitochondrial function, but how well mitochondria adapt to the new fate is unknown. Here, we determined the comprehensive mitochondrial proteome of cortical astrocytes and neurons, identifying about 150 significantly enriched mitochondrial proteins for each cell type, including transporters, metabolic enzymes, and cell-type-specific antioxidants. Monitoring their transition during reprogramming revealed late and only partial adaptation to the neuronal identity. Early dCas9-mediated activation of genes encoding mitochondrial proteins significantly improved conversion efficiency, particularly for neuron-enriched but not astrocyte-enriched antioxidant proteins. For example, Sod1 not only improves the survival of the converted neurons but also elicits a faster conversion pace, indicating that mitochondrial proteins act as enablers and drivers in this process. Transcriptional engineering of mitochondrial proteins with other functions improved reprogramming as well, demonstrating a broader role of mitochondrial proteins during fate conversion. Mitochondrial proteomes of cortical astrocytes and neurons are distinct Astrocyte-enriched mitochondrial proteins are downregulated late in neuronal conversion Neuron-enriched mitochondrial proteins are upregulated late in neuronal conversion Early induction of neuronal mitochondrial proteins improves neuronal reprogramming
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Affiliation(s)
- Gianluca L Russo
- Physiological Genomics, Biomedical Center (BMC), Ludwig-Maximilians-Universität (LMU), Planegg-Martinsried, Germany; Institute for Stem Cell Research, Helmholtz Center Munich, BMC LMU, Planegg-Martinsried, Germany; Graduate School of Systemic Neurosciences, BMC, LMU, Planegg-Martinsried, Germany
| | - Giovanna Sonsalla
- Physiological Genomics, Biomedical Center (BMC), Ludwig-Maximilians-Universität (LMU), Planegg-Martinsried, Germany; Institute for Stem Cell Research, Helmholtz Center Munich, BMC LMU, Planegg-Martinsried, Germany; Graduate School of Systemic Neurosciences, BMC, LMU, Planegg-Martinsried, Germany
| | - Poornemaa Natarajan
- Physiological Genomics, Biomedical Center (BMC), Ludwig-Maximilians-Universität (LMU), Planegg-Martinsried, Germany; Institute for Stem Cell Research, Helmholtz Center Munich, BMC LMU, Planegg-Martinsried, Germany; Graduate School of Systemic Neurosciences, BMC, LMU, Planegg-Martinsried, Germany
| | - Christopher T Breunig
- MCN Junior Research Group, Munich Center for Neurosciences, BMC, LMU, Planegg-Martinsried, Germany; Epigenetic Engineering, Institute of Stem Cell Research, Helmholtz Zentrum, Planegg-Martinsried, Germany
| | - Giorgia Bulli
- Physiological Genomics, Biomedical Center (BMC), Ludwig-Maximilians-Universität (LMU), Planegg-Martinsried, Germany; Institute for Stem Cell Research, Helmholtz Center Munich, BMC LMU, Planegg-Martinsried, Germany
| | - Juliane Merl-Pham
- Research Unit Protein Science, Helmholtz Center Munich, Neuherberg, Germany
| | - Sabine Schmitt
- Institute of Toxicology and Environmental Hygiene, School of Medicine, Technical University Munich (TUM), Munich, Germany
| | | | - Florian Giesert
- Institute of Developmental Genetics, Helmholtz Center Munich, Neuherberg, Germany; Developmental Genetics, TUM, Munich-Weihenstephan, Germany
| | - Martin Jastroch
- Department of Molecular Biosciences, The Wenner-Gren Institute, The Arrhenius Laboratories F3, Stockholm University, Stockholm, Sweden
| | - Hans Zischka
- Institute of Toxicology and Environmental Hygiene, School of Medicine, Technical University Munich (TUM), Munich, Germany; Institute of Molecular Toxicology and Pharmacology, Helmholtz Center Munich, Neuherberg, Germany
| | - Wolfgang Wurst
- Institute of Developmental Genetics, Helmholtz Center Munich, Neuherberg, Germany; Developmental Genetics, TUM, Munich-Weihenstephan, Germany; German Center for Neurodegenerative Diseases (DZNE) Site Munich, Munich, Germany
| | - Stefan H Stricker
- MCN Junior Research Group, Munich Center for Neurosciences, BMC, LMU, Planegg-Martinsried, Germany; Epigenetic Engineering, Institute of Stem Cell Research, Helmholtz Zentrum, Planegg-Martinsried, Germany
| | - Stefanie M Hauck
- Research Unit Protein Science, Helmholtz Center Munich, Neuherberg, Germany
| | - Giacomo Masserdotti
- Physiological Genomics, Biomedical Center (BMC), Ludwig-Maximilians-Universität (LMU), Planegg-Martinsried, Germany; Institute for Stem Cell Research, Helmholtz Center Munich, BMC LMU, Planegg-Martinsried, Germany
| | - Magdalena Götz
- Physiological Genomics, Biomedical Center (BMC), Ludwig-Maximilians-Universität (LMU), Planegg-Martinsried, Germany; Institute for Stem Cell Research, Helmholtz Center Munich, BMC LMU, Planegg-Martinsried, Germany; Excellence Cluster of Systems Neurology (SYNERGY), Munich, Germany.
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16
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Scheffer IE, Boysen KE, Schneider AL, Myers CT, Mehaffey MG, Rochtus AM, Yuen YP, Ronen GM, Chak WK, Gill D, Poduri A, Mefford HC. BRAT1 encephalopathy: a recessive cause of epilepsy of infancy with migrating focal seizures. Dev Med Child Neurol 2020; 62:1096-1099. [PMID: 31868227 DOI: 10.1111/dmcn.14428] [Citation(s) in RCA: 14] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Accepted: 11/04/2019] [Indexed: 01/03/2023]
Abstract
Epilepsy of infancy with migrating focal seizures (EIMFS), one of the most severe developmental and epileptic encephalopathy syndromes, is characterized by seizures that migrate from one hemisphere to the other. EIMFS is genetically heterogeneous with 33 genes. We report five patients with EIMFS caused by recessive BRAT1 variants, identified via next generation sequencing. Recessive pathogenic variants in BRAT1 cause the rigidity and multifocal seizure syndrome, lethal neonatal with hypertonia, microcephaly, and intractable multifocal seizures. The epileptology of BRAT1 encephalopathy has not been well described. All five patients were profoundly impaired with seizure onset in the first week of life and focal seizure migration between hemispheres. We show that BRAT1 is an important recessive cause of EIMFS with onset in the first week of life, profound impairment, and early death. Early recognition of this genetic aetiology will inform management and reproductive counselling.
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Affiliation(s)
- Ingrid E Scheffer
- Epilepsy Research Centre, Department of Medicine, Austin Health, University of Melbourne, Heidelberg, Victoria, Australia.,Florey Institute of Neuroscience and Mental Health, Heidelberg, Victoria, Australia.,Murdoch Children's Research Institute, Parkville, Victoria, Australia.,Department of Paediatrics, Royal Children's Hospital, Parkville, Victoria, Australia
| | - Katja E Boysen
- Epilepsy Research Centre, Department of Medicine, Austin Health, University of Melbourne, Heidelberg, Victoria, Australia
| | - Amy L Schneider
- Epilepsy Research Centre, Department of Medicine, Austin Health, University of Melbourne, Heidelberg, Victoria, Australia
| | - Candace T Myers
- Division of Genetic Medicine, Department of Pediatrics, University of Washington, Seattle, WA, USA
| | - Michele G Mehaffey
- Division of Genetic Medicine, Department of Pediatrics, University of Washington, Seattle, WA, USA
| | - Anne M Rochtus
- Epilepsy Genetics Program, Department of Neurology, Boston Children's Hospital, Boston, MA, USA.,Department of Neurology, Harvard Medical School, Boston, MA, USA
| | | | - Gabriel M Ronen
- Department of Pediatrics, McMaster University, Hamilton, Ontario, Canada
| | - Wai Km Chak
- Tuen Mun Hospital, New Territories, West Cluster, Hong Kong
| | - Deepak Gill
- T. Y. Nelson Department of Neurology and Neurosurgery, The Children's Hospital at Westmead, Sydney, New South Wales, Australia
| | - Annapurna Poduri
- Epilepsy Genetics Program, Department of Neurology, Boston Children's Hospital, Boston, MA, USA.,Department of Neurology, Harvard Medical School, Boston, MA, USA
| | - Heather C Mefford
- Division of Genetic Medicine, Department of Pediatrics, University of Washington, Seattle, WA, USA
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17
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Hillen AEJ, Heine VM. Glutamate Carrier Involvement in Mitochondrial Dysfunctioning in the Brain White Matter. Front Mol Biosci 2020; 7:151. [PMID: 32793632 PMCID: PMC7385250 DOI: 10.3389/fmolb.2020.00151] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/14/2020] [Accepted: 06/18/2020] [Indexed: 11/24/2022] Open
Abstract
Glutamate homeostasis is an important determinant of health of the central nervous system (CNS). Mitochondria play crucial roles in glutamate metabolism, especially in processes with a high energy demand such as action potential generation. Mitochondrial glutamate carriers (GCs) and aspartate-GCs (AGCs) regulate the transport of glutamate from the cytoplasm across the mitochondrial membrane, which is needed to control energy demand, lipid metabolism, and metabolic activity including oxidative phosphorylation and glycolysis. Dysfunction in these carriers are associated with seizures, spasticity, and/or myelin deficits, all of which are associated with inherited metabolic disorders. Since solute carrier functioning and associated processes are cell type- and context-specific, selective vulnerability to glutamate excitotoxicity and mitochondrial dysfunctioning is expected. Understanding this could offer important insights into the pathomechanisms of associated disorders. This perspective aims to explore the link between functions of both AGCs and GCs and their role in metabolic disorders, with a focus on a subclass of lysosomal storage disorders called leukodystrophies (LDs).
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Affiliation(s)
- Anne E J Hillen
- Pediatric Neurology, Emma Children's Hospital, Amsterdam UMC, Amsterdam Neuroscience, Vrije Universiteit Amsterdam, Amsterdam, Netherlands
| | - Vivi M Heine
- Child and Youth Psychiatry, Emma Children's Hospital, Amsterdam UMC, Amsterdam Neuroscience, Vrije Universiteit Amsterdam, Amsterdam, Netherlands.,Department of Complex Trait Genetics, Center for Neurogenomics and Cognitive Research, Amsterdam Neuroscience, Vrije Universiteit Amsterdam, Amsterdam, Netherlands
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18
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Palmieri F, Scarcia P, Monné M. Diseases Caused by Mutations in Mitochondrial Carrier Genes SLC25: A Review. Biomolecules 2020; 10:biom10040655. [PMID: 32340404 PMCID: PMC7226361 DOI: 10.3390/biom10040655] [Citation(s) in RCA: 71] [Impact Index Per Article: 17.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/27/2020] [Revised: 04/15/2020] [Accepted: 04/17/2020] [Indexed: 12/13/2022] Open
Abstract
In the 1980s, after the mitochondrial DNA (mtDNA) had been sequenced, several diseases resulting from mtDNA mutations emerged. Later, numerous disorders caused by mutations in the nuclear genes encoding mitochondrial proteins were found. A group of these diseases are due to defects of mitochondrial carriers, a family of proteins named solute carrier family 25 (SLC25), that transport a variety of solutes such as the reagents of ATP synthase (ATP, ADP, and phosphate), tricarboxylic acid cycle intermediates, cofactors, amino acids, and carnitine esters of fatty acids. The disease-causing mutations disclosed in mitochondrial carriers range from point mutations, which are often localized in the substrate translocation pore of the carrier, to large deletions and insertions. The biochemical consequences of deficient transport are the compartmentalized accumulation of the substrates and dysfunctional mitochondrial and cellular metabolism, which frequently develop into various forms of myopathy, encephalopathy, or neuropathy. Examples of diseases, due to mitochondrial carrier mutations are: combined D-2- and L-2-hydroxyglutaric aciduria, carnitine-acylcarnitine carrier deficiency, hyperornithinemia-hyperammonemia-homocitrillinuria (HHH) syndrome, early infantile epileptic encephalopathy type 3, Amish microcephaly, aspartate/glutamate isoform 1 deficiency, congenital sideroblastic anemia, Fontaine progeroid syndrome, and citrullinemia type II. Here, we review all the mitochondrial carrier-related diseases known until now, focusing on the connections between the molecular basis, altered metabolism, and phenotypes of these inherited disorders.
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Affiliation(s)
- Ferdinando Palmieri
- Department of Biosciences, Biotechnologies and Biopharmaceutics, Laboratory of Biochemistry and Molecular Biology, University of Bari Aldo Moro, via E. Orabona 4, 70125 Bari, Italy;
- Correspondence: (F.P.); (M.M.); Tel.: +39-0805443323 (F.P.)
| | - Pasquale Scarcia
- Department of Biosciences, Biotechnologies and Biopharmaceutics, Laboratory of Biochemistry and Molecular Biology, University of Bari Aldo Moro, via E. Orabona 4, 70125 Bari, Italy;
| | - Magnus Monné
- Department of Biosciences, Biotechnologies and Biopharmaceutics, Laboratory of Biochemistry and Molecular Biology, University of Bari Aldo Moro, via E. Orabona 4, 70125 Bari, Italy;
- Department of Sciences, University of Basilicata, via Ateneo Lucano 10, 85100 Potenza, Italy
- Correspondence: (F.P.); (M.M.); Tel.: +39-0805443323 (F.P.)
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19
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Burgess R, Wang S, McTague A, Boysen KE, Yang X, Zeng Q, Myers KA, Rochtus A, Trivisano M, Gill D, Sadleir LG, Specchio N, Guerrini R, Marini C, Zhang YH, Mefford HC, Kurian MA, Poduri AH, Scheffer IE. The Genetic Landscape of Epilepsy of Infancy with Migrating Focal Seizures. Ann Neurol 2020; 86:821-831. [PMID: 31618474 DOI: 10.1002/ana.25619] [Citation(s) in RCA: 77] [Impact Index Per Article: 19.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/03/2019] [Revised: 08/30/2019] [Accepted: 10/06/2019] [Indexed: 12/29/2022]
Abstract
OBJECTIVE Epilepsy of infancy with migrating focal seizures (EIMFS) is one of the most severe developmental and epileptic encephalopathies. We delineate the genetic causes and genotype-phenotype correlations of a large EIMFS cohort. METHODS Phenotypic and molecular data were analyzed on patients recruited through an international collaborative study. RESULTS We ascertained 135 patients from 128 unrelated families. Ninety-three of 135 (69%) had causative variants (42/55 previously reported) across 23 genes, including 9 novel EIMFS genes: de novo dominant GABRA1, GABRB1, ATP1A3; X-linked CDKL5, PIGA; and recessive ITPA, AIMP1, KARS, WWOX. The most frequently implicated genes were KCNT1 (36/135, 27%) and SCN2A (10/135, 7%). Mosaicism occurred in 2 probands (SCN2A, GABRB3) and 3 unaffected mothers (KCNT1). Median age at seizure onset was 4 weeks, with earlier onset in the SCN2A, KCNQ2, and BRAT1 groups. Epileptic spasms occurred in 22% patients. A total of 127 patients had severe to profound developmental impairment. All but 7 patients had ongoing seizures. Additional features included microcephaly, movement disorders, spasticity, and scoliosis. Mortality occurred in 33% at median age 2 years 7 months. INTERPRETATION We identified a genetic cause in 69% of patients with EIMFS. We highlight the genetic heterogeneity of EIMFS with 9 newly implicated genes, bringing the total number to 33. Mosaicism was observed in probands and parents, carrying critical implications for recurrence risk. EIMFS pathophysiology involves diverse molecular processes from gene and protein regulation to ion channel function and solute trafficking. ANN NEUROL 2019;86:821-831.
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Affiliation(s)
- Rosemary Burgess
- Epilepsy Research Centre, Department of Medicine, University of Melbourne, Austin Health, Melbourne, Victoria, Australia
| | - Shuyu Wang
- Epilepsy Research Centre, Department of Medicine, University of Melbourne, Austin Health, Melbourne, Victoria, Australia.,School of Clinical Sciences, Monash University, Monash Health, Melbourne, Victoria, Australia
| | - Amy McTague
- Molecular Neurosciences, Developmental Neurosciences, University College London Great Ormond Street Institute of Child Health, London, United Kingdom
| | - Katja E Boysen
- Epilepsy Research Centre, Department of Medicine, University of Melbourne, Austin Health, Melbourne, Victoria, Australia
| | - Xiaoling Yang
- Department of Pediatrics, Peking University First Hospital, Beijing, China
| | - Qi Zeng
- Department of Pediatrics, Peking University First Hospital, Beijing, China
| | - Kenneth A Myers
- Epilepsy Research Centre, Department of Medicine, University of Melbourne, Austin Health, Melbourne, Victoria, Australia.,Research Institute of the McGill University Health Centre; Montreal, Quebec, Canada.,Division of Neurology, Department of Pediatrics, Montreal Children's Hospital, McGill University Health Centre, Montreal, Quebec, Canada
| | - Anne Rochtus
- Epilepsy Genetics Program, Boston Children's Hospital, Boston, MA
| | - Marina Trivisano
- Rare and Complex Epilepsies Unit, Department of Neuroscience, Bambino Gesù Children's Hospital, Scientific Institute for Research and Health Care, Rome, Italy
| | - Deepak Gill
- T. Y. Nelson Department of Neurology and Neurosurgery, Children's Hospital at Westmead, Sydney, New South Wales, Australia
| | | | - Lynette G Sadleir
- Department of Paediatrics and Child Health, University of Otago Wellington, Wellington, New Zealand
| | - Nicola Specchio
- Rare and Complex Epilepsies Unit, Department of Neuroscience, Bambino Gesù Children's Hospital, Scientific Institute for Research and Health Care, Rome, Italy
| | - Renzo Guerrini
- Pediatric Neurology, Neurogenetics, and Neurobiology Unit and Laboratories, Children's Hospital A. Meyer-University of Florence, Florence, Italy
| | - Carla Marini
- Pediatric Neurology, Neurogenetics, and Neurobiology Unit and Laboratories, Children's Hospital A. Meyer-University of Florence, Florence, Italy
| | - Yue-Hua Zhang
- Department of Pediatrics, Peking University First Hospital, Beijing, China
| | - Heather C Mefford
- Department of Pediatrics, Division of Genetic Medicine, University of Washington, Seattle, WA
| | - Manju A Kurian
- Molecular Neurosciences, Developmental Neurosciences, University College London Great Ormond Street Institute of Child Health, London, United Kingdom.,Department of Neurology, Great Ormond Street Hospital for Children National Health Service Foundation Trust, London, United Kingdom
| | - Annapurna H Poduri
- Epilepsy Genetics Program, Boston Children's Hospital, Boston, MA.,Department of Neurology, Harvard Medical School, Boston, MA
| | - Ingrid E Scheffer
- Epilepsy Research Centre, Department of Medicine, University of Melbourne, Austin Health, Melbourne, Victoria, Australia.,Florey Institute for Neuroscience and Mental Health, Melbourne, Victoria, Australia.,Department of Neurology, Royal Children's Hospital, Department of Paediatrics, University of Melbourne, Melbourne, Victoria, Australia.,Murdoch Children's Research Institute, Melbourne, Victoria, Australia
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20
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Tan TY, Sedmík J, Fitzgerald MP, Halevy RS, Keegan LP, Helbig I, Basel-Salmon L, Cohen L, Straussberg R, Chung WK, Helal M, Maroofian R, Houlden H, Juusola J, Sadedin S, Pais L, Howell KB, White SM, Christodoulou J, O'Connell MA. Bi-allelic ADARB1 Variants Associated with Microcephaly, Intellectual Disability, and Seizures. Am J Hum Genet 2020; 106:467-483. [PMID: 32220291 DOI: 10.1016/j.ajhg.2020.02.015] [Citation(s) in RCA: 25] [Impact Index Per Article: 6.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/12/2019] [Accepted: 02/26/2020] [Indexed: 11/15/2022] Open
Abstract
The RNA editing enzyme ADAR2 is essential for the recoding of brain transcripts. Impaired ADAR2 editing leads to early-onset epilepsy and premature death in a mouse model. Here, we report bi-allelic variants in ADARB1, the gene encoding ADAR2, in four unrelated individuals with microcephaly, intellectual disability, and epilepsy. In one individual, a homozygous variant in one of the double-stranded RNA-binding domains (dsRBDs) was identified. In the others, variants were situated in or around the deaminase domain. To evaluate the effects of these variants on ADAR2 enzymatic activity, we performed in vitro assays with recombinant proteins in HEK293T cells and ex vivo assays with fibroblasts derived from one of the individuals. We demonstrate that these ADAR2 variants lead to reduced editing activity on a known ADAR2 substrate. We also demonstrate that one variant leads to changes in splicing of ADARB1 transcript isoforms. These findings reinforce the importance of RNA editing in brain development and introduce ADARB1 as a genetic etiology in individuals with intellectual disability, microcephaly, and epilepsy.
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Affiliation(s)
- Tiong Yang Tan
- Victorian Clinical Genetics Services, Melbourne 3052, Australia; Murdoch Children's Research Institute, Melbourne 3052, Australia; Department of Pediatrics, University of Melbourne, Melbourne 3052, Australia.
| | - Jiří Sedmík
- Central European Institute of Technology, Masaryk University, Kamenice 735/5, A35, Brno 62500, Czech Republic
| | - Mark P Fitzgerald
- Division of Neurology, Departments of Neurology and Pediatrics, The Children's Hospital of Philadelphia and the Perelman School of Medicine at the University of Pennsylvania, Philadelphia, PA 19104, USA; The Epilepsy NeuroGenetics Initiative, Children's Hospital of Philadelphia, Philadelphia, PA 19104, USA
| | - Rivka Sukenik Halevy
- Raphael Recanati Genetic Institute, Rabin Medical Center-Beilinson Hospital, Petah Tikva 49100, Israel; Sackler Faculty of Medicine, Tel Aviv University, Tel Aviv 6997801, Israel
| | - Liam P Keegan
- Central European Institute of Technology, Masaryk University, Kamenice 735/5, A35, Brno 62500, Czech Republic
| | - Ingo Helbig
- Division of Neurology, Departments of Neurology and Pediatrics, The Children's Hospital of Philadelphia and the Perelman School of Medicine at the University of Pennsylvania, Philadelphia, PA 19104, USA; The Epilepsy NeuroGenetics Initiative, Children's Hospital of Philadelphia, Philadelphia, PA 19104, USA
| | - Lina Basel-Salmon
- Raphael Recanati Genetic Institute, Rabin Medical Center-Beilinson Hospital, Petah Tikva 49100, Israel; Sackler Faculty of Medicine, Tel Aviv University, Tel Aviv 6997801, Israel; Felsenstein Medical Research Center, Petah Tikva 49100, Israel
| | - Lior Cohen
- Pediatric Genetics Unit, Schneider Children's Medical Center of Israel, Petah Tikva 49100, Israel
| | - Rachel Straussberg
- Sackler Faculty of Medicine, Tel Aviv University, Tel Aviv 6997801, Israel; Pediatric Neurology Unit, Schneider Children's Medical Center of Israel, Petah Tikva 49100, Israel
| | - Wendy K Chung
- Department of Pediatrics, Columbia University Medical Center, New York, NY 10032, USA
| | - Mayada Helal
- Department of Pediatrics, Columbia University Medical Center, New York, NY 10032, USA
| | - Reza Maroofian
- Department of Neuromuscular Disorders, University College London Queen Square Institute of Neurology, London WC1N 3BG, UK
| | - Henry Houlden
- Department of Neuromuscular Disorders, University College London Queen Square Institute of Neurology, London WC1N 3BG, UK
| | | | - Simon Sadedin
- Victorian Clinical Genetics Services, Melbourne 3052, Australia; Murdoch Children's Research Institute, Melbourne 3052, Australia
| | - Lynn Pais
- Broad Center for Mendelian Genomics, Broad Institute of MIT and Harvard, Cambridge, MA 02142, USA
| | - Katherine B Howell
- Murdoch Children's Research Institute, Melbourne 3052, Australia; Department of Pediatrics, University of Melbourne, Melbourne 3052, Australia; Department of Neurology, Royal Children's Hospital, Parkville 3052, Australia
| | - Susan M White
- Victorian Clinical Genetics Services, Melbourne 3052, Australia; Murdoch Children's Research Institute, Melbourne 3052, Australia; Department of Pediatrics, University of Melbourne, Melbourne 3052, Australia
| | - John Christodoulou
- Victorian Clinical Genetics Services, Melbourne 3052, Australia; Murdoch Children's Research Institute, Melbourne 3052, Australia; Department of Pediatrics, University of Melbourne, Melbourne 3052, Australia
| | - Mary A O'Connell
- Central European Institute of Technology, Masaryk University, Kamenice 735/5, A35, Brno 62500, Czech Republic.
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21
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Poisson K, Wong M, Lee C, Cilio MR. Response to cannabidiol in epilepsy of infancy with migrating focal seizures associated with KCNT1 mutations: An open-label, prospective, interventional study. Eur J Paediatr Neurol 2020; 25:77-81. [PMID: 31926846 DOI: 10.1016/j.ejpn.2019.12.024] [Citation(s) in RCA: 11] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 06/17/2019] [Revised: 10/25/2019] [Accepted: 12/29/2019] [Indexed: 02/04/2023]
Abstract
Epilepsy of Infancy with Migrating Focal Seizures (EIMFS) is a rare, developmental and epileptic encephalopathy most commonly associated with mutations in KCNT1, a potassium channel. Polymorphous migrating focal seizures begin within 6 months of life and are pharmacoresistant to standard anticonvulsants. Additional therapies are needed to decrease seizure frequency and subsequent developmental deterioration associated with EIMFS. Cannabidiol (CBD) has recently arisen in public interest due to its potential in treatment-resistant epilepsies as demonstrated in randomized controlled trials for Dravet Syndrome and Lennox-Gastaut Syndrome. Here we evaluate the response of three patients, all diagnosed with EIMFS secondary to KCNT1 mutations, to pharmaceutical grade CBD. Two patients showed no benefit and have since voluntarily stopped CBD. One patient showed no overall reduction in seizure frequency, however showed a notable reduction in seizure intensity with possible developmental progression. Further studies are needed to assess the potential benefit of CBD in treatment-resistant epilepsies such as EIMFS, with a focus on early identification and intervention.
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Affiliation(s)
- Kelsey Poisson
- Division of Neurology, Department of Pediatrics, Cincinnati Children's Hospital Medical Center and University of Cincinnati, Cincinnati, OH, 45229, USA; Department of Neurology, Wake Forest Baptist Medical Center, 1 Medical Center Blvd, Winston Salem, NC, 27157, USA.
| | - Matthew Wong
- Department of Neurology, Wake Forest Baptist Medical Center, 1 Medical Center Blvd, Winston Salem, NC, 27157, USA
| | - Chon Lee
- Department of Neurology, Wake Forest Baptist Medical Center, 1 Medical Center Blvd, Winston Salem, NC, 27157, USA; Department of Neurology, University of North Carolina Medical Center, 170 Manning Dr, Chapel Hill, NC, 27599, USA
| | - Maria Roberta Cilio
- Department of Neurology, Benioff Children's Hospital, University of California San Francisco, 1975 4th St, San Francisco, CA, USA, 94118; Department of Pediatrics and Institute of Clinical and Experimental Research, University Hospital Saint-Luc, University of Louvain, Avenue Hippocrate 10, 1200, Bruxelles, Belgium
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22
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Mao X, Bruneau N, Gao Q, Becq H, Jia Z, Xi H, Shu L, Wang H, Szepetowski P, Aniksztejn L. The Epilepsy of Infancy With Migrating Focal Seizures: Identification of de novo Mutations of the KCNT2 Gene That Exert Inhibitory Effects on the Corresponding Heteromeric K Na1.1/K Na1.2 Potassium Channel. Front Cell Neurosci 2020; 14:1. [PMID: 32038177 PMCID: PMC6992647 DOI: 10.3389/fncel.2020.00001] [Citation(s) in RCA: 9] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/11/2019] [Accepted: 01/06/2020] [Indexed: 12/21/2022] Open
Abstract
The epilepsy of infancy with migrating focal seizures (EIMFS; previously called Malignant migrating partial seizures of infancy) are early-onset epileptic encephalopathies (EOEE) that associate multifocal ictal discharges and profound psychomotor retardation. EIMFS have a genetic origin and are mostly caused by de novo mutations in the KCNT1 gene, and much more rarely in the KCNT2 gene. KCNT1 and KCNT2 respectively encode the KNa1.1 (Slack) and KNa1.2 (Slick) subunits of the sodium-dependent voltage-gated potassium channel KNa. Functional analyses of the corresponding mutant homomeric channels in vitro suggested gain-of-function effects. Here, we report two novel, de novo truncating mutations of KCNT2: one mutation is frameshift (p.L48Qfs43), is situated in the N-terminal domain, and was found in a patient with EOEE (possibly EIMFS); the other mutation is nonsense (p.K564*), is located in the C-terminal region, and was found in a typical EIMFS patient. Using whole-cell patch-clamp recordings, we have analyzed the functional consequences of those two novel KCNT2 mutations on reconstituted KNa1.2 homomeric and KNa1.1/KNa1.2 heteromeric channels in transfected chinese hamster ovary (CHO) cells. We report that both mutations significantly impacted on KNa function; notably, they decreased the global current density of heteromeric channels by ~25% (p.K564*) and ~55% (p.L48Qfs43). Overall our data emphasize the involvement of KCNT2 in EOEE and provide novel insights into the role of heteromeric KNa channel in the severe KCNT2-related epileptic phenotypes. This may have important implications regarding the elaboration of future treatment.
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Affiliation(s)
- Xiao Mao
- Hunan Provincial Maternal and Child Health Care Hospital, Changsha, China
- NHC Key Laboratory of Birth Defects Research, Prevention and Treatment, Changsha, China
| | - Nadine Bruneau
- INSERM, Aix-Marseille University, INMED, UMR1249, Marseille, France
| | - Quwen Gao
- Department of Epilepsy, General Hospital of Southern Theater Command, Guangzhou, China
| | - Hélène Becq
- INSERM, Aix-Marseille University, INMED, UMR1249, Marseille, France
| | - Zhengjun Jia
- Hunan Provincial Maternal and Child Health Care Hospital, Changsha, China
- NHC Key Laboratory of Birth Defects Research, Prevention and Treatment, Changsha, China
| | - Hui Xi
- Hunan Provincial Maternal and Child Health Care Hospital, Changsha, China
- NHC Key Laboratory of Birth Defects Research, Prevention and Treatment, Changsha, China
| | - Li Shu
- Hunan Provincial Maternal and Child Health Care Hospital, Changsha, China
- NHC Key Laboratory of Birth Defects Research, Prevention and Treatment, Changsha, China
| | - Hua Wang
- Hunan Provincial Maternal and Child Health Care Hospital, Changsha, China
- NHC Key Laboratory of Birth Defects Research, Prevention and Treatment, Changsha, China
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23
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Yahyaoui R, Pérez-Frías J. Amino Acid Transport Defects in Human Inherited Metabolic Disorders. Int J Mol Sci 2019; 21:ijms21010119. [PMID: 31878022 PMCID: PMC6981491 DOI: 10.3390/ijms21010119] [Citation(s) in RCA: 28] [Impact Index Per Article: 5.6] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/26/2019] [Revised: 12/12/2019] [Accepted: 12/18/2019] [Indexed: 02/07/2023] Open
Abstract
Amino acid transporters play very important roles in nutrient uptake, neurotransmitter recycling, protein synthesis, gene expression, cell redox balance, cell signaling, and regulation of cell volume. With regard to transporters that are closely connected to metabolism, amino acid transporter-associated diseases are linked to metabolic disorders, particularly when they involve different organs, cell types, or cell compartments. To date, 65 different human solute carrier (SLC) families and more than 400 transporter genes have been identified, including 11 that are known to include amino acid transporters. This review intends to summarize and update all the conditions in which a strong association has been found between an amino acid transporter and an inherited metabolic disorder. Many of these inherited disorders have been identified in recent years. In this work, the physiological functions of amino acid transporters will be described by the inherited diseases that arise from transporter impairment. The pathogenesis, clinical phenotype, laboratory findings, diagnosis, genetics, and treatment of these disorders are also briefly described. Appropriate clinical and diagnostic characterization of the underlying molecular defect may give patients the opportunity to avail themselves of appropriate therapeutic options in the future.
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Affiliation(s)
- Raquel Yahyaoui
- Laboratory of Metabolic Disorders and Newborn Screening Center of Eastern Andalusia, Málaga Regional University Hospital, 29011 Málaga, Spain
- Grupo Endocrinología y Nutrición, Diabetes y Obesidad, Instituto de Investigación Biomédica de Málaga-IBIMA, 29010 Málaga, Spain
- Correspondence:
| | - Javier Pérez-Frías
- Grupo Multidisciplinar de Investigación Pediátrica, Instituto de Investigación Biomédica de Málaga-IBIMA, 29010 Málaga, Spain;
- Departamento de Farmacología y Pediatría, Facultad de Medicina, Universidad de Málaga, 29010 Málaga, Spain
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24
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Mitochondrial Carriers for Aspartate, Glutamate and Other Amino Acids: A Review. Int J Mol Sci 2019; 20:ijms20184456. [PMID: 31510000 PMCID: PMC6769469 DOI: 10.3390/ijms20184456] [Citation(s) in RCA: 31] [Impact Index Per Article: 6.2] [Reference Citation Analysis] [Abstract] [Key Words] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/25/2019] [Revised: 09/05/2019] [Accepted: 09/06/2019] [Indexed: 12/19/2022] Open
Abstract
Members of the mitochondrial carrier (MC) protein family transport various molecules across the mitochondrial inner membrane to interlink steps of metabolic pathways and biochemical processes that take place in different compartments; i.e., are localized partly inside and outside the mitochondrial matrix. MC substrates consist of metabolites, inorganic anions (such as phosphate and sulfate), nucleotides, cofactors and amino acids. These compounds have been identified by in vitro transport assays based on the uptake of radioactively labeled substrates into liposomes reconstituted with recombinant purified MCs. By using this approach, 18 human, plant and yeast MCs for amino acids have been characterized and shown to transport aspartate, glutamate, ornithine, arginine, lysine, histidine, citrulline and glycine with varying substrate specificities, kinetics, influences of the pH gradient, and capacities for the antiport and uniport mode of transport. Aside from providing amino acids for mitochondrial translation, the transport reactions catalyzed by these MCs are crucial in energy, nitrogen, nucleotide and amino acid metabolism. In this review we dissect the transport properties, phylogeny, regulation and expression levels in different tissues of MCs for amino acids, and summarize the main structural aspects known until now about MCs. The effects of their disease-causing mutations and manipulation of their expression levels in cells are also considered as clues for understanding their physiological functions.
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25
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Severe early-onset developmental and epileptic encephalopathy (DEE) associated with novel compound heterozygous pathogenic variants in SLC25A22: Case report and literature review. Seizure 2019; 70:56-58. [DOI: 10.1016/j.seizure.2019.06.029] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/03/2019] [Revised: 06/03/2019] [Accepted: 06/24/2019] [Indexed: 11/18/2022] Open
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26
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Lemattre C, Imbert-Bouteille M, Gatinois V, Benit P, Sanchez E, Guignard T, Tran Mau-Them F, Haquet E, Rivier F, Carme E, Roubertie A, Boland A, Lechner D, Meyer V, Thevenon J, Duffourd Y, Rivière JB, Deleuze JF, Wells C, Molinari F, Rustin P, Blanchet P, Geneviève D. Report on three additional patients and genotype-phenotype correlation in SLC25A22-related disorders group. Eur J Hum Genet 2019; 27:1692-1700. [PMID: 31285529 DOI: 10.1038/s41431-019-0433-2] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/26/2018] [Revised: 05/06/2019] [Accepted: 05/14/2019] [Indexed: 12/12/2022] Open
Abstract
Early infantile epileptic encephalopathy (EIEE) is a heterogeneous group of severe forms of age-related developmental and epileptic encephalopathies with onset during the first weeks or months of life. The interictal electroencephalogram (EEG) shows a "suppression burst" (SB) pattern. The prognosis is usually poor and most children die within the first two years or survive with very severe intellectual disabilities. EIEE type 3 is caused by variants affecting function, in SLC25A22, which is also responsible for epilepsy of infancy with migrating focal seizures (EIMFS). We report a family with a less severe phenotype of EIEE type 3. We performed exome sequencing and identified two unreported variants in SLC25A22 in the compound heterozygous state: NM_024698.4: c.[813_814delTG];[818 G>A] (p.[Ala272Glnfs*144];[Arg273Lys]). Functional studies in cultured skin fibroblasts from a patient showed that glutamate oxidation was strongly defective, based on a literature review. We clustered the 18 published patients (including those from this family) into three groups according to the severity of the SLC25A22-related disorders. In an attempt to identify genotype-phenotype correlations, we compared the variants according to the location depending on the protein domains. We observed that patients with two variants located in helical transmembrane domains presented a severe phenotype, whereas patients with at least one variant outside helical transmembrane domains presented a milder phenotype. These data are suggestive of a continuum of disorders related to SLC25A22 that could be called SLC25A22-related disorders. This might be a first clue to enable geneticists to outline a prognosis based on genetic molecular data regarding the SLC25A22 gene.
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Affiliation(s)
- Camille Lemattre
- Département de Génétique Médicale, Maladies Rares et Médecine Personnalisée, Centre de Référence Anomalies du Développement et Syndromes Malformatifs, Université de Montpellier, CHU de Montpellier, France
| | - Marion Imbert-Bouteille
- Département de Génétique Médicale, Maladies Rares et Médecine Personnalisée, Centre de Référence Anomalies du Développement et Syndromes Malformatifs, Université de Montpellier, CHU de Montpellier, France
| | - Vincent Gatinois
- Département de Génétique Médicale, Maladies Rares et Médecine Personnalisée, Centre de Référence Anomalies du Développement et Syndromes Malformatifs, Université de Montpellier, CHU de Montpellier, France
| | - Paule Benit
- Inserm UMR 1141 - PROTECT, Hôpital Robert Debré, 48, Boulevard Sérurier, 75019, Paris, France
| | - Elodie Sanchez
- Département de Génétique Médicale, Maladies Rares et Médecine Personnalisée, Centre de Référence Anomalies du Développement et Syndromes Malformatifs, Université de Montpellier, CHU de Montpellier, France.,Unité Inserm, U1183, CHU de Montpellier, France
| | - Thomas Guignard
- Département de Génétique Médicale, Maladies Rares et Médecine Personnalisée, Centre de Référence Anomalies du Développement et Syndromes Malformatifs, Université de Montpellier, CHU de Montpellier, France
| | - Frédéric Tran Mau-Them
- Département de Génétique Médicale, Maladies Rares et Médecine Personnalisée, Centre de Référence Anomalies du Développement et Syndromes Malformatifs, Université de Montpellier, CHU de Montpellier, France.,Laboratoire de Génétique Moléculaire, Plateau Technique de Biologie, Université de Bourgogne, CHRU Dijon, France
| | - Emmanuelle Haquet
- Département de Génétique Médicale, Maladies Rares et Médecine Personnalisée, Centre de Référence Anomalies du Développement et Syndromes Malformatifs, Université de Montpellier, CHU de Montpellier, France
| | - François Rivier
- Service de Neuropédiatrie, Université de Montpellier, CHU de Montpellier, France
| | - Emilie Carme
- Service de Neuropédiatrie, Université de Montpellier, CHU de Montpellier, France
| | - Agathe Roubertie
- Service de Neuropédiatrie, Université de Montpellier, CHU de Montpellier, France
| | - Anne Boland
- Centre National de Recherche en Génomique Humaine (CNRGH), Institut de Biologie François Jacob, CEA, Université Paris-Saclay, F-91057, Evry, France
| | - Doris Lechner
- Centre National de Recherche en Génomique Humaine (CNRGH), Institut de Biologie François Jacob, CEA, Université Paris-Saclay, F-91057, Evry, France
| | - Vincent Meyer
- Centre National de Recherche en Génomique Humaine (CNRGH), Institut de Biologie François Jacob, CEA, Université Paris-Saclay, F-91057, Evry, France
| | - Julien Thevenon
- Département de Génétique et Procréation, Hôpital Couple-Enfant, Université de Grenoble, CHU de Grenoble, France
| | - Yannis Duffourd
- Laboratoire de Génétique Moléculaire, Plateau Technique de Biologie, Université de Bourgogne, CHRU Dijon, France
| | - Jean-Baptiste Rivière
- Laboratoire de Génétique Moléculaire, Plateau Technique de Biologie, Université de Bourgogne, CHRU Dijon, France
| | - Jean-François Deleuze
- Centre National de Recherche en Génomique Humaine (CNRGH), Institut de Biologie François Jacob, CEA, Université Paris-Saclay, F-91057, Evry, France
| | - Constance Wells
- Département de Génétique Médicale, Maladies Rares et Médecine Personnalisée, Centre de Référence Anomalies du Développement et Syndromes Malformatifs, Université de Montpellier, CHU de Montpellier, France
| | | | - Pierre Rustin
- Inserm UMR 1141 - PROTECT, Hôpital Robert Debré, 48, Boulevard Sérurier, 75019, Paris, France
| | - Patricia Blanchet
- Département de Génétique Médicale, Maladies Rares et Médecine Personnalisée, Centre de Référence Anomalies du Développement et Syndromes Malformatifs, Université de Montpellier, CHU de Montpellier, France
| | - David Geneviève
- Département de Génétique Médicale, Maladies Rares et Médecine Personnalisée, Centre de Référence Anomalies du Développement et Syndromes Malformatifs, Université de Montpellier, CHU de Montpellier, France. .,Unité Inserm, U1183, CHU de Montpellier, France.
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27
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Oses JP, Müller AP, Strogulski NR, Moreira JD, Böhmer AE, Hansel G, Carteri RB, Busnello JV, Kopczynski A, Rodolphi MS, Souza DO, Portela LV. Sustained elevation of cerebrospinal fluid glucose and lactate after a single seizure does not parallel with mitochondria energy production. Epilepsy Res 2019; 152:35-41. [PMID: 30875635 DOI: 10.1016/j.eplepsyres.2019.03.007] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/27/2018] [Revised: 02/18/2019] [Accepted: 03/09/2019] [Indexed: 12/22/2022]
Abstract
Generalized seizures trigger excessive neuronal firing that imposes large demands on the brain glucose/lactate availability and utilization, which synchronization requires an integral mitochondrial oxidative capability. We investigated whether a single convulsive crisis affects brain glucose/lactate availability and mitochondrial energy production. Adult male Wistar rats received a single injection of pentylentetrazol (PTZ, 60 mg/kg, i.p.) or saline. The cerebrospinal fluid (CSF) levels of glucose and lactate, mitochondrial respirometry, [14C]-2-deoxy-D-glucose uptake, glycogen content and cell viability in hippocampus were measured. CSF levels of glucose and lactate (mean ± SD) in control animals were 68.08 ± 11.62 mg/dL and 1.17 ± 0.32 mmol/L, respectively. Tonic-clonic seizures increased glucose levels at 10 min (96.25 ± 13.19) peaking at 60 min (113.03 ± 16.34) returning to control levels at 24 h (50.12 ± 12.81), while lactate increased at 10 min (3.23 ± 1.57) but returned to control levels at 360 min after seizures (1.58 ± 0.21). The hippocampal [14C]-2-deoxy-D-glucose uptake, glycogen content, and cell viability decreased up to 60 min after the seizures onset. Also, an uncoupling between mitochondrial oxygen consumption and ATP synthesis via FoF1-ATP synthase was observed at 10 min, 60 min and 24 h after seizures. In summary, after a convulsive seizure glucose and lactate levels immediately rise within the brain, however, considering the acute impact of this metabolic crisis, mitochondria are not able to increase energy production thereby affecting cell viability.
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Affiliation(s)
- Jean Pierre Oses
- Programa de Pós-graduação em Ciências Biológicas, Bioquímica, Laboratório de Neurotrauma e Biomarcadores, Departamento de Bioquímica, Instituto de Ciências Básicas da Saúde, Universidade Federal do Rio Grande do Sul, Porto Alegre, Brazil
| | - Alexandre Pastoris Müller
- Unidade de Ciências da Saúde, Laboratório de Bioquímica e Fisiologia do Exercício Universidade do Extremo Sul Catarinense-UNESC, Av. Universitária, 1105 - Bairro Universitário, CEP 88806-000, Criciúma, Santa Catarina, Brazil
| | - Nathan Ryzewski Strogulski
- Programa de Pós-graduação em Ciências Biológicas, Bioquímica, Laboratório de Neurotrauma e Biomarcadores, Departamento de Bioquímica, Instituto de Ciências Básicas da Saúde, Universidade Federal do Rio Grande do Sul, Porto Alegre, Brazil
| | - Julia D Moreira
- Programa de Pós-graduação em Ciências Biológicas, Bioquímica, Laboratório de Neurotrauma e Biomarcadores, Departamento de Bioquímica, Instituto de Ciências Básicas da Saúde, Universidade Federal do Rio Grande do Sul, Porto Alegre, Brazil; Departamento de Nutrição, Universidade Federal de Santa Catarina, Florianópolis, Brazil
| | - Ana Elisa Böhmer
- Programa de Pós-graduação em Ciências Biológicas, Bioquímica, Laboratório de Neurotrauma e Biomarcadores, Departamento de Bioquímica, Instituto de Ciências Básicas da Saúde, Universidade Federal do Rio Grande do Sul, Porto Alegre, Brazil
| | - Gisele Hansel
- Programa de Pós-graduação em Ciências Biológicas, Bioquímica, Laboratório de Neurotrauma e Biomarcadores, Departamento de Bioquímica, Instituto de Ciências Básicas da Saúde, Universidade Federal do Rio Grande do Sul, Porto Alegre, Brazil
| | - Randhall Bruce Carteri
- Programa de Pós-graduação em Ciências Biológicas, Bioquímica, Laboratório de Neurotrauma e Biomarcadores, Departamento de Bioquímica, Instituto de Ciências Básicas da Saúde, Universidade Federal do Rio Grande do Sul, Porto Alegre, Brazil
| | - João Vicente Busnello
- Department of Psychiatry and Behavioral Neuroscience, University of Chicago, Chicago, IL, USA
| | - Afonso Kopczynski
- Programa de Pós-graduação em Ciências Biológicas, Bioquímica, Laboratório de Neurotrauma e Biomarcadores, Departamento de Bioquímica, Instituto de Ciências Básicas da Saúde, Universidade Federal do Rio Grande do Sul, Porto Alegre, Brazil
| | - Marcelo Salimen Rodolphi
- Programa de Pós-graduação em Ciências Biológicas, Bioquímica, Laboratório de Neurotrauma e Biomarcadores, Departamento de Bioquímica, Instituto de Ciências Básicas da Saúde, Universidade Federal do Rio Grande do Sul, Porto Alegre, Brazil
| | - Diogo Onofre Souza
- Programa de Pós-graduação em Ciências Biológicas, Bioquímica, Laboratório de Neurotrauma e Biomarcadores, Departamento de Bioquímica, Instituto de Ciências Básicas da Saúde, Universidade Federal do Rio Grande do Sul, Porto Alegre, Brazil
| | - Luis Valmor Portela
- Programa de Pós-graduação em Ciências Biológicas, Bioquímica, Laboratório de Neurotrauma e Biomarcadores, Departamento de Bioquímica, Instituto de Ciências Básicas da Saúde, Universidade Federal do Rio Grande do Sul, Porto Alegre, Brazil.
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Chen MW, Wu XJ. SLC25A22 Promotes Proliferation and Metastasis of Osteosarcoma Cells via the PTEN Signaling Pathway. Technol Cancer Res Treat 2019; 17:1533033818811143. [PMID: 30482097 PMCID: PMC6259056 DOI: 10.1177/1533033818811143] [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] [Subscribe] [Scholar Register] [Indexed: 12/25/2022] Open
Abstract
Osteosarcoma is a highly malignant bone tumor. However, due to the high complexity of the occurrence and metastasis of osteosarcoma, the exact mechanism promoting its development and progression remains to be elucidated. This study highlights the causal link between solute carrier family 25 member 22 (SLC25A22) and the development, progression, and metastasis of osteosarcoma. SLC25A22 is upregulated in human osteosarcoma and predicts a poor prognosis. The upregulation of SLC25A22 in osteosarcoma tissues was significantly associated with cell proliferation, invasion, and metastasis. Studies of functional gain (overexpression) and loss (knockdown) showed that SLC25A22 significantly increases the ability of osteosarcoma cells to proliferate, as well as invade and metastasize in vitro. At the same time, the expression of SLC25A22 promoted the progression of the cellcycle of osteosarcoma cell lines and inhibited the apoptosis of osteosarcoma cells. Analysis using a mouse xenograft model showed that xenografts of SLC25A22 stable overexpressing osteosarcoma cells had a significant increase in tumor volume and weight compared to the control group. Lung metastasis models in mice showed that expression of SLC25A22 promoted lung metastasis of osteosarcoma in vivo. Furthermore, SLC25A22 inhibited phosphatase and tensin homolog expression and increased phosphorylation of protein kinase b (Akt) and Focal Adhesion Kinase (FAK) in the phosphatase and tensin homolog signaling pathway. In summary, SLC25A22 is highly expressed in osteosarcoma, promoting osteosarcoma cell proliferation and invasion by inhibiting the phosphatase and tensin homolog signaling pathway.
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Affiliation(s)
- Ming-Wei Chen
- 1 Orthopedics department, The First Affiliated Hospital of Zhengzhou University, Zhengzhou, Henan province, China
| | - Xue-Jian Wu
- 1 Orthopedics department, The First Affiliated Hospital of Zhengzhou University, Zhengzhou, Henan province, China
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29
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Du P, Liang H, Fu X, Wu P, Wang C, Chen H, Zheng B, Zhang J, Hu S, Zeng R, Liang B, Fang L. SLC25A22 promotes proliferation and metastasis by activating MAPK/ERK pathway in gallbladder cancer. Cancer Cell Int 2019; 19:33. [PMID: 30814911 PMCID: PMC6376740 DOI: 10.1186/s12935-019-0746-9] [Citation(s) in RCA: 15] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/30/2018] [Accepted: 02/04/2019] [Indexed: 02/06/2023] Open
Abstract
Background SLC25A22, a member of mitochondrial carrier system (MCS) family encoding a mitochondrial glutamate transporter, has been reported to have vital roles in promoting proliferation and migration in cancer. Gallbladder cancer (GBC) is the most common biliary tract malignancy and has a poor prognosis. We aimed to determine the expression and function of SLC25A22 in GBC. Methods Immunohistochemistry (IHC) staining analysis and quantitative real-time PCR (qRT-PCR) were conducted to determine the expression of SLC25A22 in GBC tissues. Human NOZ and GBC-SD cells were used to perform the experiments. The protein expression was detected by western-blot analysis. Cell viability was evaluated via CCK-8 assay and colony formation assay. Cell migration and invasion in vitro were investigated by wound healing and transwell assay. Annexin V/PI staining assay for apoptosis were measured by flow cytometry. The effect of SLC25A22 in vivo was conducted with subcutaneous xenograft. Results We indicated that the expression of SLC25A22 was significantly upregulated in GBC tumor tissues as well as cell lines. Downregulation of SLC25A22 inhibited GBC cell growth and proliferation in vitro and in vivo and also had an effect on metastasis of GBC cells through the EMT processes. In addition, inhibition of SLC25A22 promoted mitochondrial apoptosis via downregulating BCL-2 and upregulating cleaved PARP, Cytochrome-c, and BAX mediated by MAPK/ERK pathway. Conclusions Our study identified that SLC25A22 promoted development of GBC activating MAPK/ERK pathway. SLC25A22 has a potential to be used as a target for cancer diagnosis of GBC and related therapies.
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Affiliation(s)
- Pengcheng Du
- 1Department of General Surgery, Second Affiliated Hospital of Nanchang University, No. 1 Minde Road, Nanchang, 330006 China.,Jiangxi Province Key Laboratory of Molecular Medicine, No. 1 Minde Road, Nanchang, 330006 China
| | - Haibin Liang
- 3Department of General Surgery, Xinhua Hospital Affiliated to Shanghai Jiao Tong University School of Medicine, No. 1665 Kongjiang Road, Shanghai, 200092 China
| | - Xiaowei Fu
- 4Department of General Surgery, First Affiliated Hospital of Nanchang University, No. 17 Yongwai Main Street, Nanchang, 330006 China
| | - Peng Wu
- 1Department of General Surgery, Second Affiliated Hospital of Nanchang University, No. 1 Minde Road, Nanchang, 330006 China
| | - Chao Wang
- 1Department of General Surgery, Second Affiliated Hospital of Nanchang University, No. 1 Minde Road, Nanchang, 330006 China
| | - Haimin Chen
- 1Department of General Surgery, Second Affiliated Hospital of Nanchang University, No. 1 Minde Road, Nanchang, 330006 China
| | - Bingbing Zheng
- 1Department of General Surgery, Second Affiliated Hospital of Nanchang University, No. 1 Minde Road, Nanchang, 330006 China
| | - Jun Zhang
- 1Department of General Surgery, Second Affiliated Hospital of Nanchang University, No. 1 Minde Road, Nanchang, 330006 China
| | - Shuanghui Hu
- 1Department of General Surgery, Second Affiliated Hospital of Nanchang University, No. 1 Minde Road, Nanchang, 330006 China
| | - Rengui Zeng
- 1Department of General Surgery, Second Affiliated Hospital of Nanchang University, No. 1 Minde Road, Nanchang, 330006 China
| | - Bo Liang
- 1Department of General Surgery, Second Affiliated Hospital of Nanchang University, No. 1 Minde Road, Nanchang, 330006 China
| | - Lu Fang
- 1Department of General Surgery, Second Affiliated Hospital of Nanchang University, No. 1 Minde Road, Nanchang, 330006 China.,Jiangxi Province Key Laboratory of Molecular Medicine, No. 1 Minde Road, Nanchang, 330006 China
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30
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Ogunbona OB, Claypool SM. Emerging Roles in the Biogenesis of Cytochrome c Oxidase for Members of the Mitochondrial Carrier Family. Front Cell Dev Biol 2019; 7:3. [PMID: 30766870 PMCID: PMC6365663 DOI: 10.3389/fcell.2019.00003] [Citation(s) in RCA: 11] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/01/2018] [Accepted: 01/10/2019] [Indexed: 12/11/2022] Open
Abstract
The mitochondrial carrier family (MCF) is a group of transport proteins that are mostly localized to the inner mitochondrial membrane where they facilitate the movement of various solutes across the membrane. Although these carriers represent potential targets for therapeutic application and are repeatedly associated with human disease, research on the MCF has not progressed commensurate to their physiologic and pathophysiologic importance. Many of the 53 MCF members in humans are orphans and lack known transport substrates. Even for the relatively well-studied members of this family, such as the ADP/ATP carrier and the uncoupling protein, there exist fundamental gaps in our understanding of their biological roles including a clear rationale for the existence of multiple isoforms. Here, we briefly review this important family of mitochondrial carriers, provide a few salient examples of their diverse metabolic roles and disease associations, and then focus on an emerging link between several distinct MCF members, including the ADP/ATP carrier, and cytochrome c oxidase biogenesis. As the ADP/ATP carrier is regarded as the paradigm of the entire MCF, its newly established role in regulating translation of the mitochondrial genome highlights that we still have a lot to learn about these metabolite transporters.
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Affiliation(s)
- Oluwaseun B. Ogunbona
- Department of Physiology, School of Medicine, Johns Hopkins University, Baltimore, MD, United States
- Department of Pathology & Laboratory Medicine, School of Medicine, Emory University, Atlanta, GA, United States
| | - Steven M. Claypool
- Department of Physiology, School of Medicine, Johns Hopkins University, Baltimore, MD, United States
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31
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Kholin AA, Zavadenko NN, Fedonyuk ID, Antonets AV, Mukhin KY, Malov AG, Vshivkov MI, Anisimov GV, Il'ina ES. Early infantile epileptic encephalopathy type 14: three cases of epilepsy in infancy with migrating focal seizures due to KCNT1 mutations. Zh Nevrol Psikhiatr Im S S Korsakova 2019. [DOI: 10.17116/jnevro201911907274] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/17/2022]
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32
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Lesca G. Aspetti genetici delle epilessie. Neurologia 2018. [DOI: 10.1016/s1634-7072(18)41286-x] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/27/2022] Open
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33
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Myers CT, Stong N, Mountier EI, Helbig KL, Freytag S, Sullivan JE, Ben Zeev B, Nissenkorn A, Tzadok M, Heimer G, Shinde DN, Rezazadeh A, Regan BM, Oliver KL, Ernst ME, Lippa NC, Mulhern MS, Ren Z, Poduri A, Andrade DM, Bird LM, Bahlo M, Berkovic SF, Lowenstein DH, Scheffer IE, Sadleir LG, Goldstein DB, Mefford HC, Heinzen EL. De Novo Mutations in PPP3CA Cause Severe Neurodevelopmental Disease with Seizures. Am J Hum Genet 2017; 101:516-524. [PMID: 28942967 DOI: 10.1016/j.ajhg.2017.08.013] [Citation(s) in RCA: 35] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/21/2017] [Accepted: 08/10/2017] [Indexed: 12/30/2022] Open
Abstract
Exome sequencing has readily enabled the discovery of the genetic mutations responsible for a wide range of diseases. This success has been particularly remarkable in the severe epilepsies and other neurodevelopmental diseases for which rare, often de novo, mutations play a significant role in disease risk. Despite significant progress, the high genetic heterogeneity of these disorders often requires large sample sizes to identify a critical mass of individuals with disease-causing mutations in a single gene. By pooling genetic findings across multiple studies, we have identified six individuals with severe developmental delay (6/6), refractory seizures (5/6), and similar dysmorphic features (3/6), each harboring a de novo mutation in PPP3CA. PPP3CA encodes the alpha isoform of a subunit of calcineurin. Calcineurin encodes a calcium- and calmodulin-dependent serine/threonine protein phosphatase that plays a role in a wide range of biological processes, including being a key regulator of synaptic vesicle recycling at nerve terminals. Five individuals with de novo PPP3CA mutations were identified among 4,760 trio probands with neurodevelopmental diseases; this is highly unlikely to occur by chance (p = 1.2 × 10-8) given the size and mutability of the gene. Additionally, a sixth individual with a de novo mutation in PPP3CA was connected to this study through GeneMatcher. Based on these findings, we securely implicate PPP3CA in early-onset refractory epilepsy and further support the emerging role for synaptic dysregulation in epilepsy.
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Affiliation(s)
- Candace T Myers
- Division of Genetic Medicine, Department of Pediatrics, University of Washington, Seattle, WA 98195, USA
| | - Nicholas Stong
- Institute for Genomic Medicine, Columbia University Medical Center, New York, NY 10032, USA
| | - Emily I Mountier
- Department of Paediatrics and Child Health, University of Otago, Wellington 6242, New Zealand
| | | | - Saskia Freytag
- The Walter and Eliza Hall Institute of Medical Research, Parkville, VIC 3052, Australia; Department of Medical Biology, The University of Melbourne, Parkville, VIC 3050, Australia
| | - Joseph E Sullivan
- Department of Neurology & Pediatrics, University of California, San Francisco, San Francisco, CA 94143, USA
| | - Bruria Ben Zeev
- Sheba Medical Center, Ramat Gan, Israel, Sackler School of Medicine, Tel Aviv University, Tel Aviv 6997801, Israel
| | - Andreea Nissenkorn
- Sheba Medical Center, Ramat Gan, Israel, Sackler School of Medicine, Tel Aviv University, Tel Aviv 6997801, Israel
| | - Michal Tzadok
- Sheba Medical Center, Ramat Gan, Israel, Sackler School of Medicine, Tel Aviv University, Tel Aviv 6997801, Israel
| | - Gali Heimer
- Sheba Medical Center, Ramat Gan, Israel, Sackler School of Medicine, Tel Aviv University, Tel Aviv 6997801, Israel
| | | | - Arezoo Rezazadeh
- Division of Neurology, Epilepsy Genetics Research Program, Toronto Western Hospital, Krembil Neuroscience Centre, University of Toronto, Toronto, ON M5T 2S8, Canada
| | - Brigid M Regan
- Division of Neurology, Epilepsy Genetics Research Program, Toronto Western Hospital, Krembil Neuroscience Centre, University of Toronto, Toronto, ON M5T 2S8, Canada
| | - Karen L Oliver
- The Walter and Eliza Hall Institute of Medical Research, Parkville, VIC 3052, Australia; Epilepsy Research Centre, Department of Medicine, Austin Health, The University of Melbourne, Heidelberg, VIC 3084, Australia
| | - Michelle E Ernst
- Institute for Genomic Medicine, Columbia University Medical Center, New York, NY 10032, USA
| | - Natalie C Lippa
- Institute for Genomic Medicine, Columbia University Medical Center, New York, NY 10032, USA
| | - Maureen S Mulhern
- Institute for Genomic Medicine, Columbia University Medical Center, New York, NY 10032, USA
| | - Zhong Ren
- Institute for Genomic Medicine, Columbia University Medical Center, New York, NY 10032, USA
| | - Annapurna Poduri
- Epilepsy Genetics Program, Department of Neurology, Boston Children's Hospital and Department of Neurology, Harvard Medical School, Boston, MA 02115, USA
| | - Danielle M Andrade
- Division of Neurology, Epilepsy Genetics Research Program, Toronto Western Hospital, Krembil Neuroscience Centre, University of Toronto, Toronto, ON M5T 2S8, Canada
| | - Lynne M Bird
- Department of Pediatrics, University of California, San Diego, San Diego, CA 92037, USA; Rady Children's Hospital, San Diego, CA 92037, USA
| | - Melanie Bahlo
- The Walter and Eliza Hall Institute of Medical Research, Parkville, VIC 3052, Australia; Department of Medical Biology, The University of Melbourne, Parkville, VIC 3050, Australia
| | - Samuel F Berkovic
- Epilepsy Research Centre, Department of Medicine, Austin Health, The University of Melbourne, Heidelberg, VIC 3084, Australia
| | - Daniel H Lowenstein
- Department of Neurology, University of California, San Francisco, San Francisco, CA 94143, USA
| | - Ingrid E Scheffer
- Epilepsy Research Centre, Department of Medicine, Austin Health, The University of Melbourne, Heidelberg, VIC 3084, Australia; Florey Institute of Neuroscience and Mental Health, The University of Melbourne, Parkville, VIC 3010, Australia; Department of Paediatrics, Royal Children's Hospital, The University of Melbourne, Parkville, VIC 3050, Australia
| | - Lynette G Sadleir
- Department of Paediatrics and Child Health, University of Otago, Wellington 6242, New Zealand
| | - David B Goldstein
- Institute for Genomic Medicine, Columbia University Medical Center, New York, NY 10032, USA
| | - Heather C Mefford
- Division of Genetic Medicine, Department of Pediatrics, University of Washington, Seattle, WA 98195, USA.
| | - Erin L Heinzen
- Institute for Genomic Medicine, Columbia University Medical Center, New York, NY 10032, USA; Department of Pathology and Cell Biology, Columbia University Medical Center, New York, NY 10032, USA.
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Li X, Chung ACK, Li S, Wu L, Xu J, Yu J, Wong C, Cai Z. LC-MS-based metabolomics revealed SLC25A22 as an essential regulator of aspartate-derived amino acids and polyamines in KRAS-mutant colorectal cancer. Oncotarget 2017; 8:101333-101344. [PMID: 29254168 PMCID: PMC5731878 DOI: 10.18632/oncotarget.21093] [Citation(s) in RCA: 14] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/27/2017] [Accepted: 09/04/2017] [Indexed: 01/06/2023] Open
Abstract
SLC25A22, which encodes the mitochondrial glutamate transporter, is overexpressed in colorectal cancer (CRC) and is essential for the proliferation of CRC cells harboring KRAS mutations. However, the role of SLC25A22 on metabolic regulation in KRAS-mutant CRC cells has not been comprehensively characterized. We performed non-targeted metabolomics, targeted metabolomics and isotope kinetic analysis of KRAS-mutant DLD1 cells with or without SLC25A22 knockdown using ultra-high-performance liquid chromatography (UHPLC) coupled to Orbitrap mass spectrometry (MS) or tandem MS (MS/MS). Global metabolomics analysis identified 35 altered metabolites, which were attributed to alanine, aspartate and glutamate metabolism, urea cycle and polyamine metabolism. Targeted metabolomics including 24 metabolites revealed that most tricarboxylic acid (TCA) cycle intermediates, aspartate-derived asparagine, alanine and ornithine-derived polyamines were strongly down-regulated in SLC25A22 knockdown cells. Moreover, targeted kinetic isotope analysis showed that most of the 13C-labeled ornithine-derived polyamines were significantly decreased in SLC25A22 knockdown cells and culture medium. Exogenous addition of polyamines could significantly promote cell proliferation in DLD1 cells, highlighting their potential role as oncogenic metabolites that function downstream of SLC25A22-mediated glutamine metabolism. Collectively, SLC25A22 acts as an essential metabolic regulator during CRC progression as it promotes the synthesis of aspartate-derived amino acids and polyamines in KRAS mutant CRC cells.
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Affiliation(s)
- Xiaona Li
- State Key Laboratory of Environmental and Biological Analysis, Department of Chemistry, Hong Kong Baptist University, Hong Kong, China
| | - Arthur C K Chung
- State Key Laboratory of Environmental and Biological Analysis, Department of Chemistry, Hong Kong Baptist University, Hong Kong, China
| | - Shangfu Li
- State Key Laboratory of Environmental and Biological Analysis, Department of Chemistry, Hong Kong Baptist University, Hong Kong, China
| | - Lilan Wu
- State Key Laboratory of Environmental and Biological Analysis, Department of Chemistry, Hong Kong Baptist University, Hong Kong, China.,Guangdong Provincial Academy of Chinese Medical Sciences, The Second Affiliated Hospital of Guangzhou University of Chinese Medicine, Guangdong, China
| | - Jiaying Xu
- Institute of Digestive Disease and Department of Medicine and Therapeutics, State Key Laboratory of Digestive Disease, Li Ka Shing Institute of Health Sciences, Chinese University of Hong Kong, Hong Kong, China
| | - Jun Yu
- Institute of Digestive Disease and Department of Medicine and Therapeutics, State Key Laboratory of Digestive Disease, Li Ka Shing Institute of Health Sciences, Chinese University of Hong Kong, Hong Kong, China.,Shenzhen Research Institute, The Chinese University of Hong Kong, Guangdong, China
| | - Chichun Wong
- Institute of Digestive Disease and Department of Medicine and Therapeutics, State Key Laboratory of Digestive Disease, Li Ka Shing Institute of Health Sciences, Chinese University of Hong Kong, Hong Kong, China.,Shenzhen Research Institute, The Chinese University of Hong Kong, Guangdong, China
| | - Zongwei Cai
- State Key Laboratory of Environmental and Biological Analysis, Department of Chemistry, Hong Kong Baptist University, Hong Kong, China
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Goubert E, Mircheva Y, Lasorsa FM, Melon C, Profilo E, Sutera J, Becq H, Palmieri F, Palmieri L, Aniksztejn L, Molinari F. Inhibition of the Mitochondrial Glutamate Carrier SLC25A22 in Astrocytes Leads to Intracellular Glutamate Accumulation. Front Cell Neurosci 2017; 11:149. [PMID: 28620281 PMCID: PMC5449474 DOI: 10.3389/fncel.2017.00149] [Citation(s) in RCA: 40] [Impact Index Per Article: 5.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/02/2016] [Accepted: 05/09/2017] [Indexed: 12/16/2022] Open
Abstract
The solute carrier family 25 (SLC25) drives the import of a large diversity of metabolites into mitochondria, a key cellular structure involved in many metabolic functions. Mutations of the mitochondrial glutamate carrier SLC25A22 (also named GC1) have been identified in early epileptic encephalopathy (EEE) and migrating partial seizures in infancy (MPSI) but the pathophysiological mechanism of GC1 deficiency is still unknown, hampered by the absence of an in vivo model. This carrier is mainly expressed in astrocytes and is the principal gate for glutamate entry into mitochondria. A sufficient supply of energy is essential for the proper function of the brain and mitochondria have a pivotal role in maintaining energy homeostasis. In this work, we wanted to study the consequences of GC1 absence in an in vitro model in order to understand if glutamate catabolism and/or mitochondrial function could be affected. First, short hairpin RNA (shRNA) designed to specifically silence GC1 were validated in rat C6 glioma cells. Silencing GC1 in C6 resulted in a reduction of the GC1 mRNA combined with a decrease of the mitochondrial glutamate carrier activity. Then, primary astrocyte cultures were prepared and transfected with shRNA-GC1 or mismatch-RNA (mmRNA) constructs using the Neon® Transfection System in order to target a high number of primary astrocytes, more than 64%. Silencing GC1 in primary astrocytes resulted in a reduced nicotinamide adenine dinucleotide (Phosphate) (NAD(P)H) formation upon glutamate stimulation. We also observed that the mitochondrial respiratory chain (MRC) was functional after glucose stimulation but not activated by glutamate, resulting in a lower level of cellular adenosine triphosphate (ATP) in silenced astrocytes compared to control cells. Moreover, GC1 inactivation resulted in an intracellular glutamate accumulation. Our results show that mitochondrial glutamate transport via GC1 is important in sustaining glutamate homeostasis in astrocytes. Main Points:The mitochondrial respiratory chain is functional in absence of GC1 Lack of glutamate oxidation results in a lower global ATP level Lack of mitochondrial glutamate transport results in intracellular glutamate accumulation
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Affiliation(s)
| | - Yanina Mircheva
- INMED, INSERM, Aix-Marseille UniversitéMarseille, France.,Centre De Recherche De L'Institut Universitaire En Santé Mentale de QuébecQuebec City, QC, Canada
| | - Francesco M Lasorsa
- Department of Biosciences, Biotechnologies and Biopharmaceutics, University of Bari, and CNR Institute of Biomembranes, Bioenergetics and Molecular BiotechnologiesBari, Italy
| | | | - Emanuela Profilo
- Department of Biosciences, Biotechnologies and Biopharmaceutics, University of Bari, and CNR Institute of Biomembranes, Bioenergetics and Molecular BiotechnologiesBari, Italy
| | - Julie Sutera
- INMED, INSERM, Aix-Marseille UniversitéMarseille, France
| | - Hélène Becq
- INMED, INSERM, Aix-Marseille UniversitéMarseille, France
| | - Ferdinando Palmieri
- Department of Biosciences, Biotechnologies and Biopharmaceutics, University of Bari, and CNR Institute of Biomembranes, Bioenergetics and Molecular BiotechnologiesBari, Italy
| | - Luigi Palmieri
- Department of Biosciences, Biotechnologies and Biopharmaceutics, University of Bari, and CNR Institute of Biomembranes, Bioenergetics and Molecular BiotechnologiesBari, Italy
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36
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Reid ES, Williams H, Anderson G, Benatti M, Chong K, James C, Ocaka L, Hemingway C, Little D, Brown R, Parker A, Holden S, Footitt E, Rahman S, Gissen P, Mills PB, Clayton PT. Mutations in SLC25A22: hyperprolinaemia, vacuolated fibroblasts and presentation with developmental delay. J Inherit Metab Dis 2017; 40:385-394. [PMID: 28255779 PMCID: PMC5393281 DOI: 10.1007/s10545-017-0025-7] [Citation(s) in RCA: 14] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 11/15/2016] [Revised: 01/07/2017] [Accepted: 02/03/2017] [Indexed: 12/19/2022]
Abstract
Mutations in SLC25A22 are known to cause neonatal epileptic encephalopathy and migrating partial seizures in infancy. Using whole exome sequencing we identified four novel SLC25A22 mutations in six children from three families. Five patients presented clinical features similar to those in the literature including hypotonia, refractory neonatal-onset seizures and developmental delay. However, the sixth patients presented atypically with isolated developmental delay, developing late-onset (absence) seizures only at 7 years of age. Abnormal metabolite levels have not been documented in the nine patients described previously. One patient in our series was referred to the metabolic clinic because of persistent hyperprolinaemia and another three had raised plasma proline when tested. Analysis of the post-prandial plasma amino acid response in one patient showed abnormally high concentrations of several amino acids. This suggested that, in the fed state, when amino acids are the preferred fuel for the liver, trans-deamination of amino acids requires transportation of glutamate into liver mitochondria by SLC25A22 for deamination by glutamate dehydrogenase; SLC25A22 is an important mitochondrial glutamate transporter in liver as well as in brain. Electron microscopy of patient fibroblasts demonstrated widespread vacuolation containing neutral and phospho-lipids as demonstrated by Oil Red O and Sudan Black tinctorial staining; this might be explained by impaired activity of the proline/pyrroline-5-carboxylate (P5C) shuttle if SLC25A22 transports pyrroline-5-carboxylate/glutamate-γ-semialdehyde as well as glutamate.
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Affiliation(s)
- Emma S Reid
- Centre for Translational Omics, Genetics and Genomic Medicine, UCL Great Ormond Street Institute of Child Health, 30 Guilford Street, London, WC1N 1EH, UK
| | - Hywel Williams
- Centre for Translational Omics, Genetics and Genomic Medicine, UCL Great Ormond Street Institute of Child Health, 30 Guilford Street, London, WC1N 1EH, UK
| | - Glenn Anderson
- Histopathology Department, Great Ormond Street Hospital NHS Foundation Trust, Great Ormond Street, London, WC1N 3JH, UK
| | - Malika Benatti
- Histopathology Department, Great Ormond Street Hospital NHS Foundation Trust, Great Ormond Street, London, WC1N 3JH, UK
| | - Kling Chong
- Radiology Department, Great Ormond Street Hospital NHS Foundation Trust, Great Ormond Street, London, WC1N 3JH, UK
| | - Chela James
- Centre for Translational Omics, Genetics and Genomic Medicine, UCL Great Ormond Street Institute of Child Health, 30 Guilford Street, London, WC1N 1EH, UK
| | - Louise Ocaka
- Centre for Translational Omics, Genetics and Genomic Medicine, UCL Great Ormond Street Institute of Child Health, 30 Guilford Street, London, WC1N 1EH, UK
| | - Cheryl Hemingway
- Neurology Department, Great Ormond Street Hospital NHS Foundation Trust, Great Ormond Street, London, WC1N 3JH, UK
| | - Daniel Little
- Centre for Translational Omics, Genetics and Genomic Medicine, UCL Great Ormond Street Institute of Child Health, 30 Guilford Street, London, WC1N 1EH, UK
- The Medical Research Council Laboratory for Molecular Cell Biology, University College London, Gower Street, London, WC1E 6BT, UK
| | - Richard Brown
- Peterborough and Stamford Hospitals NHS Foundation Trust, Edith Cavell Campus, Bretton Gate, Peterborough, PE3 9GZ, UK
| | - Alasdair Parker
- Child Development Centre, Addenbrooke's Hospital, Cambridge, CB2 0QQ, UK
| | - Simon Holden
- Clinical Genetics, Addenbrooke's Hospital, Cambridge, CB2 0QQ, UK
| | - Emma Footitt
- Metabolic Medicine Department, Great Ormond Street Hospital NHS Foundation Trust, Great Ormond Street, London, WC1N 3JH, UK
| | - Shamima Rahman
- Metabolic Medicine Department, Great Ormond Street Hospital NHS Foundation Trust, Great Ormond Street, London, WC1N 3JH, UK
- Mitochondrial Research Group, Genetics and Genomic Medicine, UCL Great Ormond Street Institute of Child Health, 30 Guilford Street, London, WC1N 1EH, UK
| | - Paul Gissen
- Centre for Translational Omics, Genetics and Genomic Medicine, UCL Great Ormond Street Institute of Child Health, 30 Guilford Street, London, WC1N 1EH, UK
- The Medical Research Council Laboratory for Molecular Cell Biology, University College London, Gower Street, London, WC1E 6BT, UK
- Metabolic Medicine Department, Great Ormond Street Hospital NHS Foundation Trust, Great Ormond Street, London, WC1N 3JH, UK
| | - Philippa B Mills
- Centre for Translational Omics, Genetics and Genomic Medicine, UCL Great Ormond Street Institute of Child Health, 30 Guilford Street, London, WC1N 1EH, UK
| | - Peter T Clayton
- Centre for Translational Omics, Genetics and Genomic Medicine, UCL Great Ormond Street Institute of Child Health, 30 Guilford Street, London, WC1N 1EH, UK.
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Shen D, Hernandez CC, Shen W, Hu N, Poduri A, Shiedley B, Rotenberg A, Datta AN, Leiz S, Patzer S, Boor R, Ramsey K, Goldberg E, Helbig I, Ortiz-Gonzalez XR, Lemke JR, Marsh ED, Macdonald RL. De novo GABRG2 mutations associated with epileptic encephalopathies. Brain 2017; 140:49-67. [PMID: 27864268 PMCID: PMC5226060 DOI: 10.1093/brain/aww272] [Citation(s) in RCA: 74] [Impact Index Per Article: 10.6] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/10/2016] [Revised: 09/05/2016] [Accepted: 09/10/2016] [Indexed: 12/17/2022] Open
Abstract
Epileptic encephalopathies are a devastating group of severe childhood onset epilepsies with medication-resistant seizures and poor developmental outcomes. Many epileptic encephalopathies have a genetic aetiology and are often associated with de novo mutations in genes mediating synaptic transmission, including GABAA receptor subunit genes. Recently, we performed next generation sequencing on patients with a spectrum of epileptic encephalopathy phenotypes, and we identified five novel (A106T, I107T, P282S, R323W and F343L) and one known (R323Q) de novo GABRG2 pathogenic variants (mutations) in eight patients. To gain insight into the molecular basis for how these mutations contribute to epileptic encephalopathies, we compared the effects of the mutations on the properties of recombinant α1β2γ2L GABAA receptors transiently expressed in HEK293T cells. Using a combination of patch clamp recording, immunoblotting, confocal imaging and structural modelling, we characterized the effects of these GABRG2 mutations on GABAA receptor biogenesis and channel function. Compared with wild-type α1β2γ2L receptors, GABAA receptors containing a mutant γ2 subunit had reduced cell surface expression with altered subunit stoichiometry or decreased GABA-evoked whole-cell current amplitudes, but with different levels of reduction. While a causal role of these mutations cannot be established directly from these results, the functional analysis together with the genetic information suggests that these GABRG2 variants may be major contributors to the epileptic encephalopathy phenotypes. Our study further expands the GABRG2 phenotypic spectrum and supports growing evidence that defects in GABAergic neurotransmission participate in the pathogenesis of genetic epilepsies including epileptic encephalopathies.
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Affiliation(s)
- Dingding Shen
- 1 The Graduate Program of Neuroscience, Vanderbilt University, Nashville, TN 37232, USA
| | - Ciria C Hernandez
- 2 Department of Neurology, Vanderbilt University, Nashville, TN 37240, USA
| | - Wangzhen Shen
- 2 Department of Neurology, Vanderbilt University, Nashville, TN 37240, USA
| | - Ningning Hu
- 2 Department of Neurology, Vanderbilt University, Nashville, TN 37240, USA
| | - Annapurna Poduri
- 3 Epilepsy Genetics Program and the Department of Neurology, Boston Children's Hospital, Boston, MA 02115, USA
- 4 Harvard Medical School, Boston, MA 02115, USA
| | - Beth Shiedley
- 3 Epilepsy Genetics Program and the Department of Neurology, Boston Children's Hospital, Boston, MA 02115, USA
| | - Alex Rotenberg
- 3 Epilepsy Genetics Program and the Department of Neurology, Boston Children's Hospital, Boston, MA 02115, USA
| | - Alexandre N Datta
- 5 Division of Pediatric Neurology and Developmental Medicine, University of Basel Children's Hospital, Basel 4056, Switzerland
| | - Steffen Leiz
- 6 Clinic for Children and Adolescents Dritter Orden, Divison of Neuropediatrics, München, 80638 Germany
| | - Steffi Patzer
- 7 Clinic for Children and Adolescents, Halle/Saale, 06097 Germany
| | - Rainer Boor
- 8 Department of Pediatric Neurology, Kiel University, Kiel 24118 Germany; Northern German Epilepsy Centre for Children and Adolescents, Schwentinental - Raisdorf, 24223 Germany
| | - Kerri Ramsey
- 9 Center for Rare Childhood Disorders, Translational Genomics Research Institute, Phoenix, 85004 AZ, USA
| | - Ethan Goldberg
- 10 Departments of Neurology and Paediatrics, Division of Child Neurology, Perelman School of Medicine at the University of Pennsylvania, Philadelphia, PA 19104, USA
- 11 Children's Hospital of Philadelphia, Philadelphia, PA 19104, USA
| | - Ingo Helbig
- 10 Departments of Neurology and Paediatrics, Division of Child Neurology, Perelman School of Medicine at the University of Pennsylvania, Philadelphia, PA 19104, USA
- 11 Children's Hospital of Philadelphia, Philadelphia, PA 19104, USA
| | - Xilma R Ortiz-Gonzalez
- 10 Departments of Neurology and Paediatrics, Division of Child Neurology, Perelman School of Medicine at the University of Pennsylvania, Philadelphia, PA 19104, USA
- 11 Children's Hospital of Philadelphia, Philadelphia, PA 19104, USA
| | - Johannes R Lemke
- 12 Institute of Human Genetics, University of Leipzig Hospitals and Clinics, Leipzig, 04103 Germany
| | - Eric D Marsh
- 10 Departments of Neurology and Paediatrics, Division of Child Neurology, Perelman School of Medicine at the University of Pennsylvania, Philadelphia, PA 19104, USA
- 11 Children's Hospital of Philadelphia, Philadelphia, PA 19104, USA
| | - Robert L Macdonald
- 2 Department of Neurology, Vanderbilt University, Nashville, TN 37240, USA
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38
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Shbarou R. Current Treatment Options for Early-Onset Pediatric Epileptic Encephalopathies. Curr Treat Options Neurol 2016; 18:44. [DOI: 10.1007/s11940-016-0428-z] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/21/2022]
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39
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Itakura A, Saito Y, Nishimura Y, Okazaki T, Ohno K, Sejima H, Yamamoto T, Maegaki Y. Successful treatment of migrating partial seizures in Wolf-Hirschhorn syndrome with bromide. Brain Dev 2016; 38:658-62. [PMID: 26797656 DOI: 10.1016/j.braindev.2016.01.001] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 10/15/2015] [Revised: 12/26/2015] [Accepted: 01/04/2016] [Indexed: 11/19/2022]
Abstract
A girl with mild psychomotor developmental delay developed right or left hemiclonic convulsion at 10months of age. One month later, clusters of hemiclonic or bilateral tonic seizures with eyelid twitching emerged, resulting in status epilepticus. Treatment with phenobarbital and potassium bromide completely terminated the seizures within 10days. Ictal electroencephalography revealed a migrating focus of rhythmic 3-4Hz waves from the right temporal to right frontal regions and then to the left frontal regions. Genetic analysis was conducted based on the characteristic facial appearance of the patient, which identified a 2.1-Mb terminal deletion on chromosome 4p. This is the first case of Wolf-Hirschhorn syndrome complicated by epilepsy with migrating partial seizures.
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Affiliation(s)
- Ayako Itakura
- Division of Child Neurology, Department of Brain and Neurosciences, Faculty of Medicine, Tottori University, Yonago, Japan
| | - Yoshiaki Saito
- Division of Child Neurology, Department of Brain and Neurosciences, Faculty of Medicine, Tottori University, Yonago, Japan.
| | - Yoko Nishimura
- Division of Child Neurology, Department of Brain and Neurosciences, Faculty of Medicine, Tottori University, Yonago, Japan
| | - Tetsuya Okazaki
- Division of Child Neurology, Department of Brain and Neurosciences, Faculty of Medicine, Tottori University, Yonago, Japan
| | - Koyo Ohno
- Division of Child Neurology, Department of Brain and Neurosciences, Faculty of Medicine, Tottori University, Yonago, Japan
| | - Hitoshi Sejima
- Department of Pediatrics, Matsue Red-Cross Hospital, Matsue, Japan
| | - Toshiyuki Yamamoto
- Tokyo Women's Medical University Institute for Integrated Medical Sciences, Tokyo, Japan
| | - Yoshihiro Maegaki
- Division of Child Neurology, Department of Brain and Neurosciences, Faculty of Medicine, Tottori University, Yonago, Japan
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40
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Saitsu H, Watanabe M, Akita T, Ohba C, Sugai K, Ong WP, Shiraishi H, Yuasa S, Matsumoto H, Beng KT, Saitoh S, Miyatake S, Nakashima M, Miyake N, Kato M, Fukuda A, Matsumoto N. Impaired neuronal KCC2 function by biallelic SLC12A5 mutations in migrating focal seizures and severe developmental delay. Sci Rep 2016; 6:30072. [PMID: 27436767 PMCID: PMC4951812 DOI: 10.1038/srep30072] [Citation(s) in RCA: 67] [Impact Index Per Article: 8.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/05/2016] [Accepted: 06/28/2016] [Indexed: 11/09/2022] Open
Abstract
Epilepsy of infancy with migrating focal seizures (EIMFS) is one of the early-onset epileptic syndromes characterized by migrating polymorphous focal seizures. Whole exome sequencing (WES) in ten sporadic and one familial case of EIMFS revealed compound heterozygous SLC12A5 (encoding the neuronal K(+)-Cl(-) co-transporter KCC2) mutations in two families: c.279 + 1G > C causing skipping of exon 3 in the transcript (p.E50_Q93del) and c.572 C >T (p.A191V) in individuals 1 and 2, and c.967T > C (p.S323P) and c.1243 A > G (p.M415V) in individual 3. Another patient (individual 4) with migrating multifocal seizures and compound heterozygous mutations [c.953G > C (p.W318S) and c.2242_2244del (p.S748del)] was identified by searching WES data from 526 patients and SLC12A5-targeted resequencing data from 141 patients with infantile epilepsy. Gramicidin-perforated patch-clamp analysis demonstrated strongly suppressed Cl(-) extrusion function of E50_Q93del and M415V mutants, with mildly impaired function of A191V and S323P mutants. Cell surface expression levels of these KCC2 mutants were similar to wildtype KCC2. Heterologous expression of two KCC2 mutants, mimicking the patient status, produced a significantly greater intracellular Cl(-) level than with wildtype KCC2, but less than without KCC2. These data clearly demonstrated that partially disrupted neuronal Cl(-) extrusion, mediated by two types of differentially impaired KCC2 mutant in an individual, causes EIMFS.
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Affiliation(s)
- Hirotomo Saitsu
- Department of Human Genetics, Graduate School of Medicine, Yokohama City University, 3-9 Fukuura, Yokohama 236-0004, Japan
| | - Miho Watanabe
- Department of Neurophysiology, Hamamatsu University School of Medicine, 1-20-1 Handayama, Hamamatsu 431-3192, Japan
| | - Tenpei Akita
- Department of Neurophysiology, Hamamatsu University School of Medicine, 1-20-1 Handayama, Hamamatsu 431-3192, Japan
| | - Chihiro Ohba
- Department of Human Genetics, Graduate School of Medicine, Yokohama City University, 3-9 Fukuura, Yokohama 236-0004, Japan
| | - Kenji Sugai
- Department of Child Neurology, National Center Hospital, National Center of Neurology and Psychiatry, 4-1-1 Ogawahigashi-cho, Kodaira, Tokyo 187-8551, Japan
| | - Winnie Peitee Ong
- Department of Genetics, Hospital Kuala Lumpur, Jalan Pahang, Kuala Lumpur 50586, Malaysia
| | - Hideaki Shiraishi
- Department of Pediatrics, Hokkaido University Graduate School of Medicine, North 15 West 7, Sapporo 060-8638, Japan
| | - Shota Yuasa
- Department of Child Neurology, National Center Hospital, National Center of Neurology and Psychiatry, 4-1-1 Ogawahigashi-cho, Kodaira, Tokyo 187-8551, Japan
| | - Hiroshi Matsumoto
- Department of Pediatrics, National Defense Medical College, 3-2 Namiki, Tokorozawa, Saitama 359-8513, Japan
| | - Khoo Teik Beng
- Department of Pediatrics, Institute of Pediatrics, Hospital Kuala Lumpur, Jalan Pahang, Kuala Lumpur 50586, Malaysia
| | - Shinji Saitoh
- Department of Pediatrics and Neonatology, Nagoya City University Graduate School of Medical Sciences, 1 Kawasumi, Mizuho-Cho, Nagoya 467-8601, Japan
| | - Satoko Miyatake
- Department of Human Genetics, Graduate School of Medicine, Yokohama City University, 3-9 Fukuura, Yokohama 236-0004, Japan
| | - Mitsuko Nakashima
- Department of Human Genetics, Graduate School of Medicine, Yokohama City University, 3-9 Fukuura, Yokohama 236-0004, Japan
| | - Noriko Miyake
- Department of Human Genetics, Graduate School of Medicine, Yokohama City University, 3-9 Fukuura, Yokohama 236-0004, Japan
| | - Mitsuhiro Kato
- Department of Pediatrics, Showa University School of Medicine, 1-5-8 Hatanodai, Tokyo 142-8666, Japan
| | - Atsuo Fukuda
- Department of Neurophysiology, Hamamatsu University School of Medicine, 1-20-1 Handayama, Hamamatsu 431-3192, Japan
| | - Naomichi Matsumoto
- Department of Human Genetics, Graduate School of Medicine, Yokohama City University, 3-9 Fukuura, Yokohama 236-0004, Japan
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41
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Mirza N, Vasieva O, Appleton R, Burn S, Carr D, Crooks D, du Plessis D, Duncan R, Farah JO, Josan V, Miyajima F, Mohanraj R, Shukralla A, Sills GJ, Marson AG, Pirmohamed M. An integrative in silico system for predicting dysregulated genes in the human epileptic focus: Application to SLC transporters. Epilepsia 2016; 57:1467-74. [PMID: 27421837 DOI: 10.1111/epi.13473] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 06/20/2016] [Indexed: 11/29/2022]
Abstract
OBJECTIVE Many different gene families are currently being investigated for their potential role in epilepsy and in the response to antiepileptic drugs. A common research challenge is identifying the members of a gene family that are most significantly dysregulated within the human epileptic focus, before taking them forward for resource-intensive functional studies. Published data about transcriptomic changes within the human epileptic focus remains incomplete. A need exists for an accurate in silico system for the prediction of dysregulated genes within the epileptic focus. We present such a bioinformatic system. We demonstrate the validity of our approach by applying it to the solute carrier (SLC) gene family. There are >400 known SLCs. SLCs have never been systematically studied in epilepsy. METHODS Using our in silico system, we predicted the SLCs likely to be dysregulated in the epileptic focus. We validated our in silico predictions by identifying ex vivo the SLCs dysregulated in epileptic foci, and determining the overlap between our in silico and ex vivo results. For the ex vivo analysis, we used a custom oligonucleotide microarray containing exon probes for all known SLCs to analyze 24 hippocampal samples obtained from surgery for pharmacoresistant mesial temporal lobe epilepsy and 24 hippocampal samples from normal postmortem controls. RESULTS There was a highly significant (p < 9.99 × 10(-7) ) overlap between the genes identified by our in silico and ex vivo strategies. The SLCs identified were either metal ion exchangers or neurotransmitter transporters, which are likely to play a part in epilepsy by influencing neuronal excitability. SIGNIFICANCE The identified SLCs are most likely to mediate pharmacoresistance in epilepsy by enhancing the intrinsic severity of epilepsy, but further functional work will be needed to fully evaluate their role. Our successful in silico strategy can be adapted in order to prioritize genes relevant to epilepsy from other gene families.
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Affiliation(s)
- Nasir Mirza
- Department of Molecular & Clinical Pharmacology, University of Liverpool, Liverpool, United Kingdom
| | - Olga Vasieva
- Institute of Integrative Biology, University of Liverpool, Liverpool, United Kingdom
| | - Richard Appleton
- The Roald Dahl EEG Unit, Paediatric Neurosciences Foundation, Alder Hey Children's NHS Foundation Trust, Liverpool, United Kingdom
| | - Sasha Burn
- Department of Neurosurgery, Alder Hey Children's NHS Foundation Trust, Liverpool, United Kingdom
| | - Daniel Carr
- Department of Molecular & Clinical Pharmacology, University of Liverpool, Liverpool, United Kingdom
| | - Daniel Crooks
- Department of Neuropathology, The Walton Centre NHS Foundation Trust, Liverpool, United Kingdom
| | - Daniel du Plessis
- Department of Cellular Pathology, Salford Royal NHS Foundation Trust, Salford, United Kingdom
| | - Roderick Duncan
- Department of Neurology, Christchurch Hospital, Christchurch, New Zealand
| | - Jibril Osman Farah
- Department of Neurosurgery, The Walton Centre NHS Foundation Trust, Liverpool, United Kingdom
| | - Vivek Josan
- Department of Neurosurgery, Salford Royal NHS Foundation Trust, Salford, United Kingdom
| | - Fabio Miyajima
- Department of Molecular & Clinical Pharmacology, University of Liverpool, Liverpool, United Kingdom
| | - Rajiv Mohanraj
- Department of Neurology, Salford Royal NHS Foundation Trust, Salford, United Kingdom
| | - Arif Shukralla
- Department of Neurology, Salford Royal NHS Foundation Trust, Salford, United Kingdom
| | - Graeme J Sills
- Department of Molecular & Clinical Pharmacology, University of Liverpool, Liverpool, United Kingdom
| | - Anthony G Marson
- Department of Molecular & Clinical Pharmacology, University of Liverpool, Liverpool, United Kingdom
| | - Munir Pirmohamed
- Department of Molecular & Clinical Pharmacology, University of Liverpool, Liverpool, United Kingdom
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42
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Characteristic Features of the Interictal EEG Background in 2 Patients With Malignant Migrating Partial Epilepsy in Infancy. J Clin Neurophysiol 2016; 32:e23-9. [PMID: 25839129 DOI: 10.1097/wnp.0000000000000178] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/27/2022] Open
Abstract
PURPOSE To describe chronological electrographic features of the interictal EEG background observed in two patients with malignant migrating partial epilepsy in infancy from neonatal to early infantile period. METHODS EEGs of two patients who fulfilled diagnostic criteria for malignant migrating partial epilepsy in infancy were acquired over the period of 6 months to monitor treatment efficacy and characterize seizures and other paroxysmal events. RESULTS Both patients followed a similar sequential pattern. A distinctive evolution from a dysmature term neonatal EEG pattern to an asynchronous suppression burst pattern was observed before the interictal background becoming continuous. CONCLUSIONS Physicians providing care to infants with intractable epilepsy and burst suppression EEG pattern should be alert to the possibility of malignant migrating partial epilepsy in infancy. An earlier diagnosis of malignant migrating partial epilepsy in infancy would help to guide diagnostic workup including genetic testing.
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43
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Shbarou R, Mikati MA. The Expanding Clinical Spectrum of Genetic Pediatric Epileptic Encephalopathies. Semin Pediatr Neurol 2016; 23:134-42. [PMID: 27544470 DOI: 10.1016/j.spen.2016.06.002] [Citation(s) in RCA: 18] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Abstract
Pediatric epileptic encephalopathies represent a clinically challenging and often devastating group of disorders that affect children at different stages of infancy and childhood. With the advances in genetic testing and neuroimaging, the etiologies of these epileptic syndromes are now better defined. The various encephalopathies that are reviewed in this article include the following: early infantile epileptic encephalopathy or Ohtahara syndrome, early myoclonic encephalopathy, epilepsy of infancy with migrating focal seizures, West syndrome, severe myoclonic epilepsy in infancy (Dravet syndrome), Landau-Kleffner syndrome, Lennox-Gastaut syndrome, and epileptic encephalopathy with continuous spike-and-wave during sleep. Their clinical features, prognosis as well as underlying genetic etiologies are presented and updated.
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Affiliation(s)
- Rolla Shbarou
- Department of Pediatrics and Adolescent Medicine, American University of Beirut, Lebanon
| | - Mohamad A Mikati
- Division of Pediatric Neurology, Children's Health Center, Duke University Medical Center, Durham, NC.
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44
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Abstract
While genetic causes of epilepsy have been hypothesized from the time of Hippocrates, the advent of new genetic technologies has played a tremendous role in elucidating a growing number of specific genetic causes for the epilepsies. This progress has contributed vastly to our recognition of the epilepsies as a diverse group of disorders, the genetic mechanisms of which are heterogeneous. Genotype-phenotype correlation, however, is not always clear. Nonetheless, the developments in genetic diagnosis raise the promise of a future of personalized medicine. Multiple genetic tests are now available, but there is no one test for all possible genetic mutations, and the balance between cost and benefit must be weighed. A genetic diagnosis, however, can provide valuable information regarding comorbidities, prognosis, and even treatment, as well as allow for genetic counseling. In this review, we will discuss the genetic mechanisms of the epilepsies as well as the specifics of particular genetic epilepsy syndromes. We will include an overview of the available genetic testing methods, the application of clinical knowledge into the selection of genetic testing, genotype-phenotype correlations of epileptic disorders, and therapeutic advances as well as a discussion of the importance of genetic counseling.
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Affiliation(s)
- Christelle M El Achkar
- Division of Epilepsy, Department of Neurology, Boston Children's Hospital, and Harvard Medical School, Fegan 9, 300 Longwood Ave, Boston, MA, 02115, USA,
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45
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Palmieri F, Monné M. Discoveries, metabolic roles and diseases of mitochondrial carriers: A review. BIOCHIMICA ET BIOPHYSICA ACTA-MOLECULAR CELL RESEARCH 2016; 1863:2362-78. [PMID: 26968366 DOI: 10.1016/j.bbamcr.2016.03.007] [Citation(s) in RCA: 159] [Impact Index Per Article: 19.9] [Reference Citation Analysis] [Abstract] [Key Words] [Subscribe] [Scholar Register] [Received: 12/18/2015] [Revised: 02/29/2016] [Accepted: 03/01/2016] [Indexed: 12/25/2022]
Abstract
Mitochondrial carriers (MCs) are a superfamily of nuclear-encoded proteins that are mostly localized in the inner mitochondrial membrane and transport numerous metabolites, nucleotides, cofactors and inorganic anions. Their unique sequence features, i.e., a tripartite structure, six transmembrane α-helices and a three-fold repeated signature motif, allow MCs to be easily recognized. This review describes how the functions of MCs from Saccharomyces cerevisiae, Homo sapiens and Arabidopsis thaliana (listed in the first table) were discovered after the genome sequence of S. cerevisiae was determined in 1996. In the genomic era, more than 50 previously unknown MCs from these organisms have been identified and characterized biochemically using a method consisting of gene expression, purification of the recombinant proteins, their reconstitution into liposomes and transport assays (EPRA). Information derived from studies with intact mitochondria, genetic and metabolic evidence, sequence similarity, phylogenetic analysis and complementation of knockout phenotypes have guided the choice of substrates that were tested in the transport assays. In addition, the diseases associated to defects of human MCs have been briefly reviewed. This article is part of a Special Issue entitled: Mitochondrial Channels edited by Pierre Sonveaux, Pierre Maechler and Jean-Claude Martinou.
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Affiliation(s)
- Ferdinando Palmieri
- Department of Biosciences, Biotechnologies and Biopharmaceutics, University of Bari, Via E. Orabona 4, 70125 Bari, Italy.
| | - Magnus Monné
- Department of Biosciences, Biotechnologies and Biopharmaceutics, University of Bari, Via E. Orabona 4, 70125 Bari, Italy; Department of Sciences, University of Basilicata, Via Ateneo Lucano 10, 85100 Potenza, Italy
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46
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Lim CX, Ricos MG, Dibbens LM, Heron SE. KCNT1mutations in seizure disorders: the phenotypic spectrum and functional effects. J Med Genet 2016; 53:217-25. [DOI: 10.1136/jmedgenet-2015-103508] [Citation(s) in RCA: 67] [Impact Index Per Article: 8.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/09/2015] [Accepted: 12/06/2015] [Indexed: 01/01/2023]
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47
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Myers C, Mefford H. Genetic investigations of the epileptic encephalopathies. PROGRESS IN BRAIN RESEARCH 2016; 226:35-60. [DOI: 10.1016/bs.pbr.2016.04.006] [Citation(s) in RCA: 18] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/26/2022]
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48
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Kearney JA. Locus Heterogeneity in Epilepsy of Infancy with Migrating Focal Seizures. Epilepsy Curr 2016; 16:43-5. [PMID: 26900380 PMCID: PMC4749118 DOI: 10.5698/1535-7597-16.1.43] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/18/2022] Open
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49
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Hardies K, Weckhuysen S, De Jonghe P, Suls A. Lessons learned from gene identification studies in Mendelian epilepsy disorders. Eur J Hum Genet 2015; 24:961-7. [PMID: 26603999 DOI: 10.1038/ejhg.2015.251] [Citation(s) in RCA: 18] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/27/2015] [Revised: 10/05/2015] [Accepted: 10/29/2015] [Indexed: 01/23/2023] Open
Abstract
Next-generation sequencing (NGS) technologies are now routinely used for gene identification in Mendelian disorders. Setting up cost-efficient NGS projects and managing the large amount of variants remains, however, a challenging job. Here we provide insights in the decision-making processes before and after the use of NGS in gene identification studies. Genetic factors are thought to have a role in ~70% of all epilepsies, and a variety of inheritance patterns have been described for seizure-associated gene defects. We therefore chose epilepsy as disease model and selected 35 NGS studies that focused on patients with a Mendelian epilepsy disorder. The strategies used for gene identification and their respective outcomes were reviewed. High-throughput NGS strategies have led to the identification of several new epilepsy-causing genes, enlarging our knowledge on both known and novel pathomechanisms. NGS findings have furthermore extended the awareness of phenotypical and genetic heterogeneity. By discussing recent studies we illustrate: (I) the power of NGS for gene identification in Mendelian disorders, (II) the accelerating pace in which this field evolves, and (III) the considerations that have to be made when performing NGS studies. Nonetheless, the enormous rise in gene discovery over the last decade, many patients and families included in gene identification studies still remain without a molecular diagnosis; hence, further genetic research is warranted. On the basis of successful NGS studies in epilepsy, we discuss general approaches to guide human geneticists and clinicians in setting up cost-efficient gene identification NGS studies.
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Affiliation(s)
- Katia Hardies
- VIB-Department of Molecular Genetics, Neurogenetics Group, University of Antwerp, Antwerp, Belgium.,Laboratory of Neurogenetics, Institute Born-Bunge, University of Antwerp, Antwerp, Belgium
| | - Sarah Weckhuysen
- VIB-Department of Molecular Genetics, Neurogenetics Group, University of Antwerp, Antwerp, Belgium.,Laboratory of Neurogenetics, Institute Born-Bunge, University of Antwerp, Antwerp, Belgium
| | - Peter De Jonghe
- VIB-Department of Molecular Genetics, Neurogenetics Group, University of Antwerp, Antwerp, Belgium.,Laboratory of Neurogenetics, Institute Born-Bunge, University of Antwerp, Antwerp, Belgium.,Division of Neurology, Antwerp University Hospital, Antwerp, Belgium
| | - Arvid Suls
- VIB-Department of Molecular Genetics, Neurogenetics Group, University of Antwerp, Antwerp, Belgium.,Laboratory of Neurogenetics, Institute Born-Bunge, University of Antwerp, Antwerp, Belgium
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50
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Zsurka G, Kunz WS. Mitochondrial dysfunction and seizures: the neuronal energy crisis. Lancet Neurol 2015; 14:956-66. [PMID: 26293567 DOI: 10.1016/s1474-4422(15)00148-9] [Citation(s) in RCA: 151] [Impact Index Per Article: 16.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/19/2015] [Revised: 06/19/2015] [Accepted: 06/24/2015] [Indexed: 12/21/2022]
Abstract
Seizures are often the key manifestation of neurological diseases caused by pathogenic mutations in 169 of the genes that have so far been identified to affect mitochondrial function. Mitochondria are the main producers of ATP needed for normal electrical activities of neurons and synaptic transmission. Additionally, they have a central role in neurotransmitter synthesis, calcium homoeostasis, redox signalling, production and modulation of reactive oxygen species, and neuronal death. Hypotheses link mitochondrial failure to seizure generation through changes in calcium homoeostasis, oxidation of ion channels and neurotransmitter transporters by reactive oxygen species, a decrease in neuronal plasma membrane potential, and reduced network inhibition due to interneuronal dysfunction. Seizures, irrespective of their origin, represent an excessive acute energy demand in the brain. Accordingly, secondary mitochondrial dysfunction has been described in various epileptic disorders, including disorders that are mainly of non-mitochondrial origin. An understanding of the reciprocal relation between mitochondrial dysfunction and epilepsy is crucial to select appropriate anticonvulsant treatment and has the potential to open up new therapeutic approaches in the subset of epileptic disorders caused by mitochondrial dysfunction.
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Affiliation(s)
- Gábor Zsurka
- Division of Neurochemistry, Department of Epileptology, and Life & Brain Center, University of Bonn, Bonn, Germany
| | - Wolfram S Kunz
- Division of Neurochemistry, Department of Epileptology, and Life & Brain Center, University of Bonn, Bonn, Germany.
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