1
|
Pan C, Mao S, Xiong Z, Chen Z, Xu N. Glutamate dehydrogenase: Potential therapeutic targets for neurodegenerative disease. Eur J Pharmacol 2023; 950:175733. [PMID: 37116563 DOI: 10.1016/j.ejphar.2023.175733] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/24/2022] [Revised: 03/31/2023] [Accepted: 04/17/2023] [Indexed: 04/30/2023]
Abstract
Glutamate dehydrogenase (GDH) is a key enzyme in mammalian glutamate metabolism. It is located at the intersection of multiple metabolic pathways and participates in a variety of cellular activities. GDH activity is strictly regulated by a variety of allosteric compounds. Here, we review the unique distribution and expressions of GDH in the brain nervous system. GDH plays an essential role in the glutamate-glutamine-GABA cycle between astrocytes and neurons. The dysfunction of GDH may induce the occurrence of many neurodegenerative diseases, such as Parkinson's disease, epilepsy, Alzheimer's disease, schizophrenia, and frontotemporal dementia. GDH activators and gene therapy have been found to protect neurons and improve motor disorders in neurodegenerative diseases caused by glutamate metabolism disorders. To date, no medicine has been discovered that specifically targets neurodegenerative diseases, although several potential medicines are used clinically. Targeting GDH to treat neurodegenerative diseases is expected to provide new insights and treatment strategies.
Collapse
Affiliation(s)
- Chuqiao Pan
- College of Pharmaceutical Science, Institute of Drug Development & Chemical Biology, Zhejiang University of Technology, Huzhou, 313200, Zhejiang, People's Republic of China
| | - Shijie Mao
- College of Pharmaceutical Science, Institute of Drug Development & Chemical Biology, Zhejiang University of Technology, Huzhou, 313200, Zhejiang, People's Republic of China
| | - Zeping Xiong
- Department of Collaborative Innovation Center of Yangtze River Delta Region Green Pharmaceuticals, Zhejiang University of Technology, Huzhou, 313200, Zhejiang, People's Republic of China
| | - Zhao Chen
- College of Pharmaceutical Science, Institute of Drug Development & Chemical Biology, Zhejiang University of Technology, Huzhou, 313200, Zhejiang, People's Republic of China
| | - Ning Xu
- College of Pharmaceutical Science, Institute of Drug Development & Chemical Biology, Zhejiang University of Technology, Huzhou, 313200, Zhejiang, People's Republic of China.
| |
Collapse
|
2
|
Aftab S, Gubaeva D, Houghton JAL, Dastamani A, Sotiridou E, Gilbert C, Flanagan SE, Tiulpakov A, Melikyan M, Shah P. Spectrum of neuro-developmental disorders in children with congenital hyperinsulinism due to activating mutations in GLUD1. Endocr Connect 2023; 12:e220008. [PMID: 35951311 PMCID: PMC10077222 DOI: 10.1530/ec-22-0008] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 06/25/2022] [Accepted: 08/11/2022] [Indexed: 11/08/2022]
Abstract
Background Hyperinsulinism/hyperammonemia (HI/HA) syndrome is the second most common type of congenital hyperinsulinism caused by an activating GLUD1 mutation. Objective The aim of this study was to determine the clinical profile and long-term neurological outcomes in children with HI/HA syndrome. Method This study is a retrospective review of patients with GLUD1 mutation, treated at two centers in the UK and Russia, over a 15-year period. Different risk factors for neuro-developmental disorders were analysed by Mann-Whitney U test and Fisher's exact P test. Results We identified 25 cases with GLUD1 mutations (12 males). Median age of presentation was 7 months (12 h-18 months). Hypoglycaemic seizures were the presenting feature in 24 (96%) cases. Twenty four cases responded to diazoxide and protein restriction whilst one patient underwent partial pancreatectomy. In total, 13 cases (52%) developed neurodevelopmental manifestations. Epilepsy (n = 9/25, 36%), learning difficulties (n = 8/25, 32%) and speech delay (n = 8/25, 32%) were the most common neurological manifestation. Median age of presentation for epilepsy was 12 months with generalised tonic-clonic seizures being the most common (n = 4/9, 44.4%) followed by absence seizures (n = 3/9, 33.3%). Early age of presentation (P = 0.02), diazoxide dose (P = 0.04) and a mutation in exon 11 or 12 (P = 0.01) were associated with neurological disorder. Conclusion HI/HA syndrome is associated with wide spectrum of neurological disorders. These neurological manifestations were more frequent in cases with mutations affecting the GTP-binding site of GLUD1 in our cohort.
Collapse
Affiliation(s)
- Sommayya Aftab
- Department of Paediatric Endocrinology, Great Ormond Street Hospital, London, UK
| | - Diliara Gubaeva
- Department of Paediatric Endocrinology, Endocrinology Research Centre, Moscow, Russia
| | - Jayne A L Houghton
- The Genomics Laboratory, Royal Devon & Exeter NHS Foundation Trust, Exeter, UK
| | - Antonia Dastamani
- Department of Paediatric Endocrinology, Great Ormond Street Hospital, London, UK
| | - Ellada Sotiridou
- Department of Paediatric Endocrinology, Great Ormond Street Hospital, London, UK
| | - Clare Gilbert
- Department of Paediatric Endocrinology, Great Ormond Street Hospital, London, UK
| | - Sarah E Flanagan
- Institute of Biomedical and Clinical Science, University of Exeter Medical School, Exeter, UK
| | - Anatoly Tiulpakov
- Department of Paediatric Endocrinology, Endocrinology Research Centre, Moscow, Russia
| | - Maria Melikyan
- Department of Paediatric Endocrinology, Endocrinology Research Centre, Moscow, Russia
| | - Pratik Shah
- Department of Paediatric Endocrinology, Great Ormond Street Hospital, London, UK
| |
Collapse
|
3
|
Feng Y, Zhang C, Wei Z, Li G, Gan Y, Liu C, Deng Y. Gene variations of glutamate metabolism pathway and epilepsy. ACTA EPILEPTOLOGICA 2022. [DOI: 10.1186/s42494-022-00103-2] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/10/2022] Open
Abstract
Abstract
Background
Epilepsy is a paroxysmal disorder of the brain, caused by an imbalance of neuronal excitation and inhibition. Glutamate is the most important excitatory neurotransmitter in the brain and plays an important role in epileptogenesis. Mutations in genes at any step/component of the glutamate metabolic pathway may lead to the development of epilepsy or epileptic encephalopathy.
Methods
Clinical history of 3 epilepsy patients with genetic variations of the glutamate metabolism pathway was collected. Electroencephalogram recording and magnetic resonance imaging were performed in each patient. We also reviewed recent literature for a variety of the genetic variations involved in epilepsy.
Results
Case 1 was a SLC1A2 mutation-carrier diagnosed with developmental and epileptic encephalopathy (DEE) 41, whose seizures decreased after start of the ketogenic diet. Case 2 carried a GRIN2A gene mutation and was seizure-free for three years after taking levetiracetam and vitamin B6. Case 3 was a GRIN2B mutation-carrier diagnosed with DEE 27, who seizures diminished after taking oxcarbazepine.
Conclusions
Preclinical and clinical evidence supports the therapeutic potential of glutamatergic signaling-targeting treatments for epilepsy. More studies are needed to discover novel DEE-related genetic mutations in the glutamate metabolic pathway.
Collapse
|
4
|
Rosenfeld E, Nanga RPR, Lucas A, Revell AY, Thomas A, Thomas NH, Roalf DR, Shinohara RT, Reddy R, Davis KA, De León DD. Characterizing the neurological phenotype of the hyperinsulinism hyperammonemia syndrome. Orphanet J Rare Dis 2022; 17:248. [PMID: 35752848 PMCID: PMC9233810 DOI: 10.1186/s13023-022-02398-3] [Citation(s) in RCA: 4] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/05/2022] [Accepted: 06/11/2022] [Indexed: 11/10/2022] Open
Abstract
BACKGROUND Hyperinsulinism hyperammonemia (HI/HA) syndrome is caused by activating mutations in GLUD1, encoding glutamate dehydrogenase (GDH). Atypical absence seizures and neuropsychological disorders occur at high rates in this form of hyperinsulinism. Dysregulated central nervous system (CNS) glutamate balance, due to GDH overactivity in the brain, has been hypothesized to play a role. This study aimed to describe the neurologic phenotype in HI/HA syndrome and investigate CNS glutamate levels using glutamate weighted chemical exchange saturation transfer magnetic resonance imaging (GluCEST MRI). In this cross-sectional study, 12 subjects with HI/HA syndrome had plasma ammonia measurement, self- or parent-completed neurocognitive assessments, electroencephalogram (EEG), and GluCEST MRI at 7 T performed. GluCEST MRI measures were compared to a historic reference population of 10 healthy adults. RESULTS Subjects were five males and seven females with median age of 25.5 years. Seventy-five percent of subjects reported a history of neurodevelopmental problems and 42% had neurocognitive assessment scores outside the normal range. Fifty percent had interictal EEG findings of generalized, irregular spike and wave discharges. Higher variability in hippocampal GluCEST asymmetry (p = 0.002), and in peak hippocampal GluCEST values (p = 0.008), was observed in HI/HA subjects (n = 9 with interpretable MRI) compared to the healthy reference population (n = 10). CONCLUSIONS The high prevalence of abnormal neurocognitive assessment scores and interictal EEG findings observed highlights the importance of longitudinal neuropsychological assessment for individuals with HI/HA syndrome. Our findings demonstrate the potential application of GluCEST to investigate persistent knowledge gaps in the mechanisms underlying the unique neurophenotype of this disorder.
Collapse
Affiliation(s)
- Elizabeth Rosenfeld
- Division of Endocrinology and Diabetes, Children's Hospital of Philadelphia, 3500 Civic Center Boulevard, Philadelphia, PA, 19140, USA. .,Congenital Hyperinsulinism Center, Children's Hospital of Philadelphia, Philadelphia, PA, USA. .,Department of Pediatrics, Perelman School of Medicine, University of Pennsylvania, Philadelphia, PA, USA.
| | - Ravi Prakash Reddy Nanga
- Center for Advanced Metabolic Imaging in Precision Medicine, Hospital of the University of Pennsylvania, Philadelphia, PA, USA
| | - Alfredo Lucas
- Penn Center for Neuroengineering and Therapeutics, University of Pennsylvania, Philadelphia, PA, USA
| | - Andrew Y Revell
- Penn Center for Neuroengineering and Therapeutics, University of Pennsylvania, Philadelphia, PA, USA
| | - Allison Thomas
- Behavioral Neuroscience Core, Center for Human Phenomic Science, Children's Hospital of Philadelphia, Philadelphia, PA, USA
| | - Nina H Thomas
- Behavioral Neuroscience Core, Center for Human Phenomic Science, Children's Hospital of Philadelphia, Philadelphia, PA, USA.,Department of Child and Adolescent Psychiatry and Behavioral Sciences, Children's Hospital of Philadelphia, Philadelphia, PA, USA.,Department of Psychiatry, University of Pennsylvania Perelman School of Medicine, Philadelphia, PA, USA
| | - David R Roalf
- Department of Psychiatry, University of Pennsylvania Perelman School of Medicine, Philadelphia, PA, USA
| | - Russel T Shinohara
- Penn Statistics in Imaging and Visualization Center, Department of Biostatistics, Epidemiology, and Informatics, University of Pennsylvania Perelman School of Medicine, Philadelphia, PA, USA.,Center for Biomedical Image Computing and Analytics, Department of Radiology, University of Pennsylvania Perelman School of Medicine, Philadelphia, PA, USA
| | - Ravinder Reddy
- Center for Advanced Metabolic Imaging in Precision Medicine, Hospital of the University of Pennsylvania, Philadelphia, PA, USA
| | - Kathryn A Davis
- Penn Center for Neuroengineering and Therapeutics, University of Pennsylvania, Philadelphia, PA, USA.,Department of Neurology, University of Pennsylvania Perelman School of Medicine, Philadelphia, PA, USA
| | - Diva D De León
- Division of Endocrinology and Diabetes, Children's Hospital of Philadelphia, 3500 Civic Center Boulevard, Philadelphia, PA, 19140, USA.,Congenital Hyperinsulinism Center, Children's Hospital of Philadelphia, Philadelphia, PA, USA.,Department of Pediatrics, Perelman School of Medicine, University of Pennsylvania, Philadelphia, PA, USA
| |
Collapse
|
5
|
Specchio N, Wirrell EC, Scheffer IE, Nabbout R, Riney K, Samia P, Guerreiro M, Gwer S, Zuberi SM, Wilmshurst JM, Yozawitz E, Pressler R, Hirsch E, Wiebe S, Cross HJ, Perucca E, Moshé SL, Tinuper P, Auvin S. International League Against Epilepsy classification and definition of epilepsy syndromes with onset in childhood: Position paper by the ILAE Task Force on Nosology and Definitions. Epilepsia 2022; 63:1398-1442. [PMID: 35503717 DOI: 10.1111/epi.17241] [Citation(s) in RCA: 220] [Impact Index Per Article: 110.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/24/2021] [Revised: 03/16/2022] [Accepted: 03/17/2022] [Indexed: 12/30/2022]
Abstract
The 2017 International League Against Epilepsy classification has defined a three-tier system with epilepsy syndrome identification at the third level. Although a syndrome cannot be determined in all children with epilepsy, identification of a specific syndrome provides guidance on management and prognosis. In this paper, we describe the childhood onset epilepsy syndromes, most of which have both mandatory seizure type(s) and interictal electroencephalographic (EEG) features. Based on the 2017 Classification of Seizures and Epilepsies, some syndrome names have been updated using terms directly describing the seizure semiology. Epilepsy syndromes beginning in childhood have been divided into three categories: (1) self-limited focal epilepsies, comprising four syndromes: self-limited epilepsy with centrotemporal spikes, self-limited epilepsy with autonomic seizures, childhood occipital visual epilepsy, and photosensitive occipital lobe epilepsy; (2) generalized epilepsies, comprising three syndromes: childhood absence epilepsy, epilepsy with myoclonic absence, and epilepsy with eyelid myoclonia; and (3) developmental and/or epileptic encephalopathies, comprising five syndromes: epilepsy with myoclonic-atonic seizures, Lennox-Gastaut syndrome, developmental and/or epileptic encephalopathy with spike-and-wave activation in sleep, hemiconvulsion-hemiplegia-epilepsy syndrome, and febrile infection-related epilepsy syndrome. We define each, highlighting the mandatory seizure(s), EEG features, phenotypic variations, and findings from key investigations.
Collapse
Affiliation(s)
- Nicola Specchio
- Rare and Complex Epilepsy Unit, Department of Neuroscience, Bambino Gesù Children's Hospital, Scientific Institute for Research and Health Care, Full Member of EpiCARE, Rome, Italy
| | - Elaine C Wirrell
- Divisions of Child and Adolescent Neurology and Epilepsy, Department of Neurology, Mayo Clinic, Rochester, Minnesota, USA
| | - Ingrid E Scheffer
- Austin Health and Royal Children's Hospital, Florey Institute, Murdoch Children's Research Institute, University of Melbourne, Melbourne, Victoria, Australia
| | - Rima Nabbout
- Reference Center for Rare Epilepsies, Department of Pediatric Neurology, Necker-Sick Children Hospital, Public Hospital Network of Paris, member of EpiCARE, Imagine Institute, National Institute of Health and Medical Research, Mixed Unit of Research 1163, University of Paris, Paris, France
| | - Kate Riney
- Neurosciences Unit, Queensland Children's Hospital, South Brisbane, Queensland, Australia.,Faculty of Medicine, University of Queensland, South Brisbane, Queensland, Australia
| | - Pauline Samia
- Department of Pediatrics and Child Health, Aga Khan University, Nairobi, Kenya
| | | | - Sam Gwer
- School of Medicine, Kenyatta University, and Afya Research Africa, Nairobi, Kenya
| | - Sameer M Zuberi
- Paediatric Neurosciences Research Group, Royal Hospital for Children and Institute of Health & Wellbeing, member of EpiCARE, University of Glasgow, Glasgow, UK
| | - Jo M Wilmshurst
- Department of Paediatric Neurology, Red Cross War Memorial Children's Hospital, Neuroscience Institute, University of Cape Town, Cape Town, South Africa
| | - Elissa Yozawitz
- Isabelle Rapin Division of Child Neurology of the Saul R. Korey Department of Neurology, Montefiore Medical Center, Bronx, New York, USA
| | - Ronit Pressler
- Programme of Developmental Neurosciences, University College London National Institute for Health Research Biomedical Research Centre Great Ormond Street Institute of Child Health, Department of Clinical Neurophysiology, Great Ormond Street Hospital for Children, London, UK
| | - Edouard Hirsch
- Neurology Epilepsy Units "Francis Rohmer", INSERM 1258, FMTS, Strasbourg University, Strasbourg, France
| | - Sam Wiebe
- Department of Clinical Neurosciences, University of Calgary, Calgary, Alberta, Canada
| | - Helen J Cross
- Programme of Developmental Neurosciences, University College London National Institute for Health Research Biomedical Research Centre Great Ormond Street Institute of Child Health, Great Ormond Street Hospital for Children, and Young Epilepsy Lingfield, London, UK
| | - Emilio Perucca
- Department of Neuroscience, Monash University, Melbourne, Victoria, Australia.,Department of Medicine, Austin Health, University of Melbourne, Heidelberg, Victoria, Australia
| | - Solomon L Moshé
- Isabelle Rapin Division of Child Neurology, Saul R. Korey Department of Neurology, and Departments of Neuroscience and Pediatrics, Albert Einstein College of Medicine and Montefiore Medical Center, Bronx, New York, USA
| | - Paolo Tinuper
- Department of Biomedical and Neuromotor Sciences, University of Bologna, Bologna, Italy.,Institute of Neurological Sciences, Scientific Institute for Research and Health Care, Bologna, Italy
| | - Stéphane Auvin
- Robert Debré Hospital, Public Hospital Network of Paris, NeuroDiderot, National Institute of Health and Medical Research, Department Medico-Universitaire Innovation Robert-Debré, Pediatric Neurology, University of Paris, Paris, France
| |
Collapse
|
6
|
Dehghan F, Zamani S, Barreiro C, Jami MS. Irisin injection mimics exercise effects on the brain proteome. Eur J Neurosci 2021; 54:7422-7441. [PMID: 34655501 DOI: 10.1111/ejn.15493] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/20/2021] [Revised: 09/30/2021] [Accepted: 10/02/2021] [Indexed: 12/13/2022]
Abstract
Physical inactivity can endanger human health and increase the incidence of neurodegenerative disease. Exercise has tremendous beneficial effects on brain health and cognitive function, especially in older adults. It also improves brain-related outcomes in depression, epilepsy and neurodegenerative disorders, such as Parkinson's disease and Alzheimer's disease. Irisin is a mediator of the beneficial effects of exercise. This study aimed to assess the proteome alterations in adult male National Maritime Research Institute (NMRI) mice brain tissue upon three different conditions including endurance exercise, resistance exercise and irisin injection. Quantification of irisin levels in blood was performed using irisin-ELISA Kit. Quantification and identification of proteins via two-dimensional gel electrophoresis and matrix-assisted laser desorption ionization time-of-flight (MALDI-TOF) mass spectrometry (MS)/MS showed the alteration of at least 21 proteins due to different treatments. Cellular pathway analysis revealed common beneficial effects of sole irisin treatment and different exercise procedures suggesting the capability of irisin injection to substitute the exercise when physical activity is not possible.
Collapse
Affiliation(s)
- Fariba Dehghan
- Cellular and Molecular Research Center, Basic Health Sciences Institute, Shahrekord University of Medical Sciences, Shahrekord, Iran
| | - Saeed Zamani
- Department of Anatomical Sciences, School of Medicine, Shahrekord University of Medical Sciences, Shahrekord, Iran.,Department of Anatomical Sciences, Isfahan University of Medical Sciences, Isfahan, Iran
| | - Carlos Barreiro
- INBIOTEC (Instituto de Biotecnología de León), León, Spain.,Biochemistry and Molecular Biology Area, Department of Molecular Biology, University of León, Vegazana Campus, León, Spain
| | - Mohammad-Saeid Jami
- Cellular and Molecular Research Center, Basic Health Sciences Institute, Shahrekord University of Medical Sciences, Shahrekord, Iran.,QIANBIOTEC, Research and Development Center for Biotechnology, Isfahan, Iran.,Department of Neurology, David Geffen School of Medicine, University of California Los Angeles (UCLA), Los Angeles, California, USA
| |
Collapse
|
7
|
Gobbo D, Scheller A, Kirchhoff F. From Physiology to Pathology of Cortico-Thalamo-Cortical Oscillations: Astroglia as a Target for Further Research. Front Neurol 2021; 12:661408. [PMID: 34177766 PMCID: PMC8219957 DOI: 10.3389/fneur.2021.661408] [Citation(s) in RCA: 9] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/30/2021] [Accepted: 05/11/2021] [Indexed: 12/21/2022] Open
Abstract
The electrographic hallmark of childhood absence epilepsy (CAE) and other idiopathic forms of epilepsy are 2.5-4 Hz spike and wave discharges (SWDs) originating from abnormal electrical oscillations of the cortico-thalamo-cortical network. SWDs are generally associated with sudden and brief non-convulsive epileptic events mostly generating impairment of consciousness and correlating with attention and learning as well as cognitive deficits. To date, SWDs are known to arise from locally restricted imbalances of excitation and inhibition in the deep layers of the primary somatosensory cortex. SWDs propagate to the mostly GABAergic nucleus reticularis thalami (NRT) and the somatosensory thalamic nuclei that project back to the cortex, leading to the typical generalized spike and wave oscillations. Given their shared anatomical basis, SWDs have been originally considered the pathological transition of 11-16 Hz bursts of neural oscillatory activity (the so-called sleep spindles) occurring during Non-Rapid Eye Movement (NREM) sleep, but more recent research revealed fundamental functional differences between sleep spindles and SWDs, suggesting the latter could be more closely related to the slow (<1 Hz) oscillations alternating active (Up) and silent (Down) cortical activity and concomitantly occurring during NREM. Indeed, several lines of evidence support the fact that SWDs impair sleep architecture as well as sleep/wake cycles and sleep pressure, which, in turn, affect seizure circadian frequency and distribution. Given the accumulating evidence on the role of astroglia in the field of epilepsy in the modulation of excitation and inhibition in the brain as well as on the development of aberrant synchronous network activity, we aim at pointing at putative contributions of astrocytes to the physiology of slow-wave sleep and to the pathology of SWDs. Particularly, we will address the astroglial functions known to be involved in the control of network excitability and synchronicity and so far mainly addressed in the context of convulsive seizures, namely (i) interstitial fluid homeostasis, (ii) K+ clearance and neurotransmitter uptake from the extracellular space and the synaptic cleft, (iii) gap junction mechanical and functional coupling as well as hemichannel function, (iv) gliotransmission, (v) astroglial Ca2+ signaling and downstream effectors, (vi) reactive astrogliosis and cytokine release.
Collapse
Affiliation(s)
- Davide Gobbo
- Molecular Physiology, Center for Integrative Physiology and Molecular Medicine (CIPMM), University of Saarland, Homburg, Germany
| | - Anja Scheller
- Molecular Physiology, Center for Integrative Physiology and Molecular Medicine (CIPMM), University of Saarland, Homburg, Germany
| | - Frank Kirchhoff
- Molecular Physiology, Center for Integrative Physiology and Molecular Medicine (CIPMM), University of Saarland, Homburg, Germany
| |
Collapse
|
8
|
Rumping L, Vringer E, Houwen RHJ, van Hasselt PM, Jans JJM, Verhoeven‐Duif NM. Inborn errors of enzymes in glutamate metabolism. J Inherit Metab Dis 2020; 43:200-215. [PMID: 31603991 PMCID: PMC7078983 DOI: 10.1002/jimd.12180] [Citation(s) in RCA: 11] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 03/14/2019] [Revised: 10/01/2019] [Accepted: 10/04/2019] [Indexed: 12/29/2022]
Abstract
Glutamate is involved in a variety of metabolic pathways. We reviewed the literature on genetic defects of enzymes that directly metabolise glutamate, leading to inborn errors of glutamate metabolism. Seventeen genetic defects of glutamate metabolising enzymes have been reported, of which three were only recently identified. These 17 defects affect the inter-conversion of glutamine and glutamate, amino acid metabolism, ammonia detoxification, and glutathione metabolism. We provide an overview of the clinical and biochemical phenotypes of these rare defects in an effort to ease their recognition. By categorising these by biochemical pathway, we aim to create insight into the contributing role of deviant glutamate and glutamine levels to the pathophysiology. For those disorders involving the inter-conversion of glutamine and glutamate, these deviant levels are postulated to play a pivotal pathophysiologic role. For the other IEM however-with the exception of urea cycle defects-abnormal glutamate and glutamine concentrations were rarely reported. To create insight into the clinical consequences of disturbed glutamate metabolism-rather than individual glutamate and glutamine levels-the prevalence of phenotypic abnormalities within the 17 IEM was compared to their prevalence within all Mendelian disorders and subsequently all disorders with metabolic abnormalities notated in the Human Phenotype Ontology (HPO) database. For this, a hierarchical database of all phenotypic abnormalities of the 17 defects in glutamate metabolism based on HPO was created. A neurologic phenotypic spectrum of developmental delay, ataxia, seizures, and hypotonia are common in the inborn errors of enzymes in glutamate metabolism. Additionally, ophthalmologic and skin abnormalities are often present, suggesting that disturbed glutamate homeostasis affects tissues of ectodermal origin: brain, eye, and skin. Reporting glutamate and glutamine concentrations in patients with inborn errors of glutamate metabolism would provide additional insight into the pathophysiology.
Collapse
Affiliation(s)
- Lynne Rumping
- Department of GeneticsUniversity Medical Center Utrecht, Utrecht UniversityUtrechtthe Netherlands
- Center for Molecular MedicineUniversity Medical Center Utrecht, Utrecht UniversityUtrechtthe Netherlands
- Department of PediatricsUniversity Medical Center Utrecht, Utrecht UniversityUtrechtthe Netherlands
| | - Esmee Vringer
- Department of GeneticsUniversity Medical Center Utrecht, Utrecht UniversityUtrechtthe Netherlands
| | - Roderick H. J. Houwen
- Department of PediatricsUniversity Medical Center Utrecht, Utrecht UniversityUtrechtthe Netherlands
| | - Peter M. van Hasselt
- Department of PediatricsUniversity Medical Center Utrecht, Utrecht UniversityUtrechtthe Netherlands
| | - Judith J. M. Jans
- Department of GeneticsUniversity Medical Center Utrecht, Utrecht UniversityUtrechtthe Netherlands
- Center for Molecular MedicineUniversity Medical Center Utrecht, Utrecht UniversityUtrechtthe Netherlands
| | - Nanda M. Verhoeven‐Duif
- Department of GeneticsUniversity Medical Center Utrecht, Utrecht UniversityUtrechtthe Netherlands
- Center for Molecular MedicineUniversity Medical Center Utrecht, Utrecht UniversityUtrechtthe Netherlands
| |
Collapse
|
9
|
Hiraide T, Hattori A, Ieda D, Hori I, Saitoh S, Nakashima M, Saitsu H. De novo variants in SETD1B cause intellectual disability, autism spectrum disorder, and epilepsy with myoclonic absences. Epilepsia Open 2019; 4:476-481. [PMID: 31440728 PMCID: PMC6698685 DOI: 10.1002/epi4.12339] [Citation(s) in RCA: 24] [Impact Index Per Article: 4.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/14/2019] [Revised: 04/27/2019] [Accepted: 05/09/2019] [Indexed: 02/02/2023] Open
Abstract
Epilepsy with myoclonic absences is a specific seizure type characterized by bilateral rhythmic clonic jerks with impairment of consciousness. Here, we report an individual with epilepsy with myoclonic absences, mild intellectual disabilities, language disorder, and autism spectrum disorder. His interictal electroencephalogram revealed a spike-and-slow wave complex dominant in the frontal area. His ictal polygraphic and video-electroencephalogram showed a characteristic diffuse synchronous 3-Hz spike-and-wave burst associated with bilateral upper limb myoclonic jerks with impairment of consciousness. Using whole-exome sequencing, we found a novel de novo variant, c.386T>G, p.(Val129Gly), in SETD1B (SET domain containing 1B). We previously reported that two individuals with a de novo SETD1B variant showed intellectual disability, epilepsy, and autism. Of note, one of those individuals and the present case showed epilepsy with myoclonic absences. Therefore, this report supports the indication that SETD1B may be a causative gene for neurodevelopmental disorders and suggests that epilepsy with myoclonic absences may be a characteristic feature of SETD1B-related disorders.
Collapse
Affiliation(s)
- Takuya Hiraide
- Department of BiochemistryHamamatsu University School of MedicineHamamatsuJapan
- Department of PediatricsHamamatsu University School of MedicineHamamatsuJapan
| | - Ayako Hattori
- Department of Pediatrics and NeonatologyNagoya City University, Graduate School of Medical SciencesAichiJapan
| | - Daisuke Ieda
- Department of Pediatrics and NeonatologyNagoya City University, Graduate School of Medical SciencesAichiJapan
| | - Ikumi Hori
- Department of Pediatrics and NeonatologyNagoya City University, Graduate School of Medical SciencesAichiJapan
| | - Shinji Saitoh
- Department of Pediatrics and NeonatologyNagoya City University, Graduate School of Medical SciencesAichiJapan
| | - Mitsuko Nakashima
- Department of BiochemistryHamamatsu University School of MedicineHamamatsuJapan
| | - Hirotomo Saitsu
- Department of BiochemistryHamamatsu University School of MedicineHamamatsuJapan
| |
Collapse
|
10
|
Kim AY, Baik EJ. Glutamate Dehydrogenase as a Neuroprotective Target Against Neurodegeneration. Neurochem Res 2018; 44:147-153. [PMID: 29357018 DOI: 10.1007/s11064-018-2467-1] [Citation(s) in RCA: 24] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/25/2017] [Revised: 01/03/2018] [Accepted: 01/05/2018] [Indexed: 10/18/2022]
Abstract
Regulation of glutamate metabolism via glutamate dehydrogenase (GDH) might be the promising therapeutic approach for treating neurodegenerative disorders. In the central nervous system, glutamate functions both as a major excitatory neurotransmitter and as a key intermediate metabolite for neurons. GDH converts glutamate to α-ketoglutarate, which serves as a TCA cycle intermediate. Dysregulated GDH activity in the central nervous system is highly correlated with neurological disorders. Indeed, studies conducted with mutant mice and allosteric drugs have shown that deficient or overexpressed GDH activity in the brain can regulate whole body energy metabolism and affect early onset of Parkinson's disease, Alzheimer's disease, temporal lobe epilepsy, and spinocerebellar atrophy. Moreover, in strokes with excitotoxicity as the main pathophysiology, mice that overexpressed GDH exhibited smaller ischemic lesion than mice with normal GDH expression. In additions, GDH activators improve lesions in vivo by increasing α-ketoglutarate levels. In neurons exposed to an insult in vitro, enhanced GDH activity increases ATP levels. Thus, in an energy crisis, neuronal mitochondrial activity is improved and excitotoxic risk is reduced. Consequently, modulating GDH activity in energy-depleted conditions could be a sound strategy for maintaining the mitochondrial factory in neurons, and thus, protect against metabolic failure.
Collapse
Affiliation(s)
- A Young Kim
- Department of Physiology, Ajou University School of Medicine, Suwon, 16499, South Korea.,Chronic Inflammatory Disease Research Center, Ajou University School of Medicine, Suwon, 16499, South Korea
| | - Eun Joo Baik
- Department of Physiology, Ajou University School of Medicine, Suwon, 16499, South Korea. .,Chronic Inflammatory Disease Research Center, Ajou University School of Medicine, Suwon, 16499, South Korea.
| |
Collapse
|
11
|
Abstract
OPINION STATEMENT In the absence of a culprit epileptogenic lesion, pharmacoresistant seizures should prompt the physician to consider potentially treatable metabolic epilepsies, especially in the presence of developmental delays. Even though the anti-seizure treatment of the epilepsies remains symptomatic and usually tailored to an electroclinical phenotype rather than to an underlying etiology, a thorough metabolic workup might reveal a disease with an etiology-specific treatment. Early diagnosis is essential in the case of treatable metabolic epilepsies allowing timely intervention. Despite the advances in genetic testing, biochemical testing including cerebrospinal fluid studies are still needed to expedite the diagnostic workup and potential therapeutic trials. The diagnostician should have a high index of suspicion despite potential clinical digressions from seminal publications describing the initial cases, as these index patients may represent the most severe form of the condition rather than its most common presenting form. The often gratifying developmental outcome and seizure control with early treatment calls for a prompt diagnostic consideration of treatable metabolic diseases; even though relatively rare or potentially only seemingly so.
Collapse
|
12
|
Myers KA, Scheffer IE. Myoclonic Absence Seizures in Dravet Syndrome. Pediatr Neurol 2017; 70:67-69. [PMID: 28233668 DOI: 10.1016/j.pediatrneurol.2017.01.004] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 12/24/2016] [Revised: 01/03/2017] [Accepted: 01/04/2017] [Indexed: 11/17/2022]
Abstract
BACKGROUND Dravet syndrome is a developmental and epileptic encephalopathy that occurs as a result of SCN1A mutations in more than 80% of affected individuals. The core clinical features of Dravet syndrome include febrile and afebrile seizures beginning before 12 months; multiple seizure types, usually medically refractory, including hemiclonic, generalized tonic-clonic, focal impaired awareness, myoclonic, and absence seizures; status epilepticus; and normal early development with plateau or regression by age two years. Myoclonic absence seizures have not previously been described. PATIENT DESCRIPTION This 20-year-old man had infantile-onset epilepsy with the classical clinical features of Dravet syndrome and a de novo A1326P SCN1A mutation. By five years of age, photosensitive myoclonic absence seizures had become his dominant seizure type, occurring up to 20 times per day. RESULTS The seizures were refractory to multiple antiepileptic medications and a vagus nerve stimulator. CONCLUSIONS Although photosensitivity is well recognized in Dravet syndrome, myoclonic absence seizures have not been previously reported. This rare seizure type may be underreported in Dravet syndrome, as the myoclonic features may be subtle and can be missed if thorough history taking and video recordings are not available.
Collapse
Affiliation(s)
- Kenneth A Myers
- Epilepsy Research Centre, Department of Medicine, The University of Melbourne, Austin Health, Heidelberg, VIC, Australia
| | - Ingrid E Scheffer
- Epilepsy Research Centre, Department of Medicine, The University of Melbourne, Austin Health, Heidelberg, VIC, Australia; Department of Paediatrics, The University of Melbourne, Parkville, VIC, Australia; The Florey Institute of Neuroscience and Mental Health, Heidelberg, VIC, Australia; Department of Neurology, Royal Children's Hospital, Parkville, VIC, Australia.
| |
Collapse
|
13
|
Ninković D, Sarnavka V, Bašnec A, Ćuk M, Ramadža DP, Fumić K, Kušec V, Santer R, Barić I. Hyperinsulinism-hyperammonemia syndrome: a de novo mutation of the GLUD1 gene in twins and a review of the literature. J Pediatr Endocrinol Metab 2016; 29:1083-8. [PMID: 27383869 DOI: 10.1515/jpem-2016-0086] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 03/12/2016] [Accepted: 05/09/2016] [Indexed: 01/25/2023]
Abstract
Hyperinsulinism-hyperammonemia (HI/HA) syndrome is a rare autosomal dominant disease characterized by recurrent hypoglycemia and persistent mild elevation of plasma ammonia. HI/HA syndrome is one of the more common forms of congenital hyperinsulinism (CHI), caused by activating mutations within the GLUD1 gene that encodes the mitochondrial enzyme glutamate dehydrogenase (GDH). We report here on monozygotic twin girls presented with fasting- and protein-induced hypoglycemia and mild persistent hyperammonemia. Genetic analysis revealed that both girls were heterozygous for a novel missense mutation within exon 11 [c.1499A>T, p.(R443W)] of the GLUD1 gene. Despite early treatment with diazoxide and a low protein diet, they both developed non-hypoglycemic seizures in early childhood followed by cognitive impairment. In addition to their clinical course, a review of the literature on HI/HA syndrome is provided.
Collapse
|
14
|
Sarajlija A, Milenkovic T, Djordjevic M, Mitrovic K, Todorovic S, Kecman B, Hussain K. Early Presentation of Hyperinsulinism/Hyperammonemia Syndrome in Three Serbian Patients. J Clin Res Pediatr Endocrinol 2016; 8:228-31. [PMID: 26759084 PMCID: PMC5096481 DOI: 10.4274/jcrpe.2436] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 01/08/2023] Open
Abstract
Hyperinsulinism/hyperammonemia (HI/HA) syndrome is considered as the second most common type of hereditary HI. Correlation of genotype and phenotype in HI/HA syndrome has been described in several studies. We present three Serbian patients with HI/HA syndrome with emphasis on a possible correlation between genotype and clinical manifestations. Patient 1 was heterozygous for a de novo mutation p.S445L in the GLUD1 gene, while patients 2 and 3 (son and mother) both carry the p.R221C mutation. Early onset of hypoglycaemia with generalized seizures was recorded in infancy in all three patients. The two male patients had mild developmental delay, while the female patient presented with epilepsy. Analysis of Serbian patients with HI/HA syndrome confirms the association of p.S445L and p.R221C mutations with hypoglycaemic seizures noted within the first three months of life and with subsequent risk for cognitive impairment and/or epilepsy.
Collapse
Affiliation(s)
- Adrijan Sarajlija
- Mother and Child Health Care Institute of Serbia "Dr Vukan Cupic", Department of Metabolism and Clinical Genetics, Belgrade, Serbia E-mail:
| | - Tatjana Milenkovic
- Mother and Child Health Care Institute of Serbia “Dr Vukan Cupic”, Department of Endocrinology, Belgrade, Serbia
| | - Maja Djordjevic
- Mother and Child Health Care Institute of Serbia “Dr Vukan Cupic”, Department of Metabolism and Clinical Genetics, Belgrade, Serbia
,
University of Belgrade Faculty of Medicine, Belgrade, Serbia
| | - Katarina Mitrovic
- Mother and Child Health Care Institute of Serbia “Dr Vukan Cupic”, Department of Endocrinology, Belgrade, Serbia
| | - Sladjana Todorovic
- Mother and Child Health Care Institute of Serbia “Dr Vukan Cupic”, Department of Endocrinology, Belgrade, Serbia
| | - Bozica Kecman
- Mother and Child Health Care Institute of Serbia “Dr Vukan Cupic”, Department of Metabolism and Clinical Genetics, Belgrade, Serbia
| | - Khalid Hussain
- Great Ormond Street Hospital for Children NHS Trust, Department of Pediatric Endocrinology, London, United Kingdom
,
University College London, Institute of Child Health, London, United Kingdom
| |
Collapse
|
15
|
Abstract
Transient multienzyme and/or multiprotein complexes (metabolons) direct substrates toward specific pathways and can significantly influence the metabolism of glutamate and glutamine in the brain. Glutamate is the primary excitatory neurotransmitter in brain. This neurotransmitter has essential roles in normal brain function including learning and memory. Metabolism of glutamate involves the coordinated activity of astrocytes and neurons and high affinity transporter proteins that are selectively distributed on these cells. This chapter describes known and possible metabolons that affect the metabolism of glutamate and related compounds in the brain, as well as some factors that can modulate the association and dissociation of such complexes, including protein modifications by acylation reactions (e.g., acetylation, palmitoylation, succinylation, SUMOylation, etc.) of specific residues. Development of strategies to modulate transient multienzyme and/or enzyme-protein interactions may represent a novel and promising therapeutic approach for treatment of diseases involving dysregulation of glutamate metabolism.
Collapse
|
16
|
Abstract
BACKGROUND Epilepsy with myoclonic absences (EMAs) is a distinct form of childhood epilepsy characterized by a peculiar seizure type that identifies this condition. PURPOSE To describe the clinical, electroencephalographic features, treatment strategies and outcome in this first case series of two siblings with normal intelligence presenting with EMAs. MATERIALS AND METHODS Both siblings underwent video-polygraphic investigations (simultaneous recording of electroencephalogram [EEG] and electromyogram [EMG] from deltoids), high-resolution magnetic resonance imaging (MRI), karyotyping, neuropsychological evaluation and language assessment. RESULTS Both the children had a mean age of onset of prototype seizures by 3.5 years. Myoclonic absences (MAs) were characterized by rhythmic, bilateral, synchronous, symmetric 3-Hz spike-wave discharges, associated with EMG myoclonic bursts at 3 Hz, superimposed on a progressively increasing tonic muscle contraction. The interictal EEG showed a normal background activity with bursts of generalized spike and waves (SWs) as well as rare focal SWs independently over bilateral temporal and frontal regions. Increase in the seizure frequency from 5 to 100/day was observed due to use of carbamazepine and phenobarbitone which decreased with its withdrawal and introduction of valproate. Though lamotrigine was given as an add on to valproate, it did not benefit them and was therefore replaced by topiramate at 3.5 mg/kg/day which has maintained them on remission at one year follow up. CONCLUSIONS Recognition of this ictal pattern allows identification and differentiation of EMAs from other seizure types. Idiopathic and symptomatic EMAs need to be differentiated from childhood absence epilepsy with myoclonia. MAs are worsened by drugs like carbamazepine while valproate either alone or in combination with topiramate (preferred to lamotrigine) gives excellent outcome.
Collapse
|
17
|
Chandran S, Yap F, Hussain K. Molecular mechanisms of protein induced hyperinsulinaemic hypoglycaemia. World J Diabetes 2014; 5:666-677. [PMID: 25317244 PMCID: PMC4138590 DOI: 10.4239/wjd.v5.i5.666] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 01/21/2014] [Revised: 04/23/2014] [Accepted: 05/29/2014] [Indexed: 02/05/2023] Open
Abstract
The interplay between glucose metabolism and that of the two other primary nutrient classes, amino acids and fatty acids is critical for regulated insulin secretion. Mitochondrial metabolism of glucose, amino acid and fatty acids generates metabolic coupling factors (such as ATP, NADPH, glutamate, long chain acyl-CoA and diacylglycerol) which trigger insulin secretion. The observation of protein induced hypoglycaemia in patients with mutations in GLUD1 gene, encoding the enzyme glutamate dehydrogenase (GDH) and HADH gene, encoding for the enzyme short-chain 3-hydroxyacyl-CoA dehydrogenase has provided new mechanistic insights into the regulation of insulin secretion by amino acid and fatty acid metabolism. Metabolic signals arising from amino acid and fatty acid metabolism converge on the enzyme GDH which integrates both signals from both pathways and controls insulin secretion. Hence GDH seems to play a pivotal role in regulating both amino acid and fatty acid metabolism.
Collapse
|
18
|
Dulac O, Plecko B, Gataullina S, Wolf NI. Occasional seizures, epilepsy, and inborn errors of metabolism. Lancet Neurol 2014; 13:727-39. [PMID: 24943345 DOI: 10.1016/s1474-4422(14)70110-3] [Citation(s) in RCA: 25] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/31/2022]
Abstract
Seizures are a common paediatric problem, with inborn errors of metabolism being a rare underlying aetiology. The clinical presentation of inborn errors of metabolism is often associated with other neurological symptoms, such as hypotonia, movement disorders, and cognitive disturbances. However, the occurrence of epilepsy associated with inborn errors of metabolism represents a major challenge that needs to be identified quickly; for some cases, specific treatments are available, metabolic decompensation might be avoided, and accurate counselling can be given about recurrence risk. Some clinical presentations are more likely than others to point to an inborn error of metabolism as the cause of seizures. Knowledge of important findings at examination, and appropriate biochemical investigation of children with seizures of uncertain cause, can aid the diagnosis of an inborn error of metabolism and ascertain whether or not the seizures are amenable to specific metabolic treatment.
Collapse
Affiliation(s)
- Olivier Dulac
- Paris Descartes University, Inserm U1129, Paris, France; CEA, Gif-sur-Yvette, France; Department of Paediatric Neurology, Hôpital Necker-Enfants Malades, AP-HP, Paris, France.
| | - Barbara Plecko
- Department of Child Neurology, University Children's Hospital, University of Zurich, Switzerland
| | | | - Nicole I Wolf
- Department of Child Neurology, VU University Medical Center, Amsterdam, Netherlands; Neuroscience Campus Amsterdam, Amsterdam, Netherlands
| |
Collapse
|
19
|
Kroczka S, Biedroń A, Kaciński M. Epilepsy and electrophysiological findings in polish twins with glycogenosis type IIIb. Clin EEG Neurosci 2014; 45:201-4. [PMID: 24357677 DOI: 10.1177/1550059413500276] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/15/2022]
Abstract
Glycogen storage diseases are rare genetic disorders, mostly autosomal recessively inherited. Abnormal accumulation is because of the lack of one of the enzymes involved in glycogen metabolism. Neurological manifestation of the diseases involves muscle weakness and hypoglycemia-induced seizures. In this article, we present a history of twin sisters with unusual coincidence of glycogenosis type IIIb and epilepsy. Hypoglycemic background of seizures and organic changes of the central nervous system were excluded. Since the introduction of antiepileptic treatment, the patients have been seizure-free; however, paroxysmal electroencephalographic (EEG) changes have persisted. A high-protein and low-carbohydrate diet has protected them against hypoglycemia.
Collapse
|
20
|
Yu JY, Pearl PL. Metabolic causes of epileptic encephalopathy. EPILEPSY RESEARCH AND TREATMENT 2013; 2013:124934. [PMID: 23762547 PMCID: PMC3674738 DOI: 10.1155/2013/124934] [Citation(s) in RCA: 21] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 02/22/2013] [Accepted: 04/16/2013] [Indexed: 12/31/2022]
Abstract
Epileptic encephalopathy can be induced by inborn metabolic defects that may be rare individually but in aggregate represent a substantial clinical portion of child neurology. These may present with various epilepsy phenotypes including refractory neonatal seizures, early myoclonic encephalopathy, early infantile epileptic encephalopathy, infantile spasms, and generalized epilepsies which in particular include myoclonic seizures. There are varying degrees of treatability, but the outcome if untreated can often be catastrophic. The importance of early recognition cannot be overemphasized. This paper provides an overview of inborn metabolic errors associated with persistent brain disturbances due to highly active clinical or electrographic ictal activity. Selected diseases are organized by the defective molecule or mechanism and categorized as small molecule disorders (involving amino and organic acids, fatty acids, neurotransmitters, urea cycle, vitamers and cofactors, and mitochondria) and large molecule disorders (including lysosomal storage disorders, peroxisomal disorders, glycosylation disorders, and leukodystrophies). Details including key clinical features, salient electrophysiological and neuroradiological findings, biochemical findings, and treatment options are summarized for prominent disorders in each category.
Collapse
Affiliation(s)
- Joe Yuezhou Yu
- Department of Neurology, Children's National Medical Center, 111 Michigan Avnue, Washington, DC 20010, USA
| | - Phillip L. Pearl
- Department of Neurology, Children's National Medical Center, 111 Michigan Avnue, Washington, DC 20010, USA
| |
Collapse
|
21
|
|
22
|
Abstract
Epilepsies associated with inborn errors of metabolism (IEM) represent a major challenge. Seizures rarely dominate the clinical presentation, which is more frequently associated with other neurological symptoms, such as hypotonia and/or cognitive disturbances. Although epilepsy in IEM can be classified in various ways according to pathogenesis, age of onset, or electroclinical presentation, the most pragmatic approach is determined by whether they are accessible to specific treatment or not. The main potentially treatable causes comprise vitamin B6 (pyridoxine deficiency), biotine, and GLUT1 deficiency (GLUT1DS) syndromes. Folinic acid-dependent seizures are allelic with pyridoxine dependency. Incompletely treatable IEMs include pyridoxal phosphate, serine, and creatine deficiencies. The main IEMs that present with epilepsy but offer no specific treatment are nonketotic hyperglycinemia, mitochondrial disorders, sulfite oxidase deficiency, ceroid-lipofuscinosis, Menkes disease, and peroxisomal disorders.
Collapse
Affiliation(s)
- Nadia Bahi-Buisson
- Department of Pediatric Neurology, Université Paris Descartes; Imaging Institute; INSERM U781, Paris, France.
| | | |
Collapse
|
23
|
Nakano K, Kobayashi K, Okano Y, Aso K, Ohtsuka Y. Intractable absence seizures in hyperinsulinism-hyperammonemia syndrome. Pediatr Neurol 2012; 47:119-22. [PMID: 22759688 DOI: 10.1016/j.pediatrneurol.2012.04.019] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 02/03/2012] [Accepted: 04/19/2012] [Indexed: 10/28/2022]
Abstract
A girl with intractable absence seizures and facial myoclonia at age 7 years was eventually diagnosed with hyperinsulinism-hyperammonemia syndrome because of hypoglycemia, hyperinsulinism, hyperammonemia, and the results of an oral l-leucine loading test. Her seizures occurred even during periods of relatively normal blood glucose levels, and were completely suppressed by diazoxide treatment only. Her diagnosis of hyperinsulinism-hyperammonemia syndrome was confirmed by a loss of sensitivity of glutamate dehydrogenase for guanosine 5'-triphosphate. Genetic studies identified the I444M mutation in the GLUD1 gene, which encodes glutamate dehydrogenase. This case illustrates the complex relationship between seizures and hypoglycemia in hyperinsulinism-hyperammonemia syndrome that can create diagnostic difficulties. The possibility of hyperinsulinism-hyperammonemia syndrome should be considered in patients with refractory absence seizures with myoclonia.
Collapse
Affiliation(s)
- Kousuke Nakano
- Department of Pediatrics, Matsuyama Red Cross Hospital, Matsuyama, Japan.
| | | | | | | | | |
Collapse
|
24
|
Yalçın O. Genes and molecular mechanisms involved in the epileptogenesis of idiopathic absence epilepsies. Seizure 2011; 21:79-86. [PMID: 22206818 DOI: 10.1016/j.seizure.2011.12.002] [Citation(s) in RCA: 66] [Impact Index Per Article: 5.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/10/2011] [Revised: 12/02/2011] [Accepted: 12/04/2011] [Indexed: 11/16/2022] Open
Abstract
Idiopathic absence epilepsies (IAE), that have high prevalence particularly among children and adolescents, are complex disorders mainly caused by genetic factors. Childhood absence epilepsy and juvenile absence epilepsy are among the most common subtypes of IAEs. While the role of ion channels has been the primary focus of epilepsy research, the analysis of mutation and association in both patients with absence epilepsies and animal models revealed the involvement of GABA receptors and calcium channels, but also of novel non-ion channel proteins in inducing spike wave discharges (SWD). Functional studies on a mutated variant of these proteins also support their role in the epileptogenesis of absence seizures. Studies in animal models point to both the thalamus and cortex as the origin of SWDs: the abnormalities in the components of these circuits leading to seizure activity. This review examines the current research on mutations and susceptibility alleles determined in the genes that code for the subunits of GABA receptors (GABRG2, GABRA1, GABRB3, GABRA5, GABA(B1) and GABA(B2)), calcium channels (CACNA1A, CACNA1G, CACNA1H, CACNA1I, CACNAB4, CACNAG2 and CACNG3), and novel non-ion channel proteins, taking into account the results of functional studies on these variants.
Collapse
Affiliation(s)
- Ozlem Yalçın
- Department of Molecular Biology and Genetics, T.C. Istanbul Arel University, Tepekent-Buyukcekmece, Istanbul, Turkey.
| |
Collapse
|
25
|
Pérez Errazquin F, Sempere Fernández J, García Martín G, Chamorro Muñoz M, Romero Acebal M. Síndrome de hiperinsulinismo-hiperamoniemia y epilepsia mioclónica grave de la infancia. Neurologia 2011; 26:248-52. [DOI: 10.1016/j.nrl.2010.09.024] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/13/2010] [Revised: 09/10/2010] [Accepted: 09/18/2010] [Indexed: 10/18/2022] Open
|
26
|
Yalçin O, Baykan B, Ağan K, Yapici Z, Yalçin D, Dizdarer G, Türkdoğan D, Ozkara C, Unalp A, Uludüz D, Gül G, Kuşcu D, Ayta S, Tutkavul K, Comu S, Tatli B, Meral C, Bebek N, Cağlayan SH. An association analysis at 2q36 reveals a new candidate susceptibility gene for juvenile absence epilepsy and/or absence seizures associated with generalized tonic-clonic seizures. Epilepsia 2011; 52:975-83. [PMID: 21320115 DOI: 10.1111/j.1528-1167.2010.02970.x] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Abstract
PURPOSE To further evaluate the previously shown linkage of absence epilepsy (AE) to 2q36, both in human and WAG/Rij absence rat models, a 160-kb region at 2q36 containing eight genes with expressions in the brain was targeted in a case-control association study involving 205 Turkish patients with AE and 219 controls. METHODS Haplotype block and case-control association analysis was carried out using HAPLOVIEW 4.0 and inhibin alpha subunit (INHA) gene analysis by DNA sequencing. KEY FINDINGS An association was found between the G allele of rs7588807 located in the INHA gene and juvenile absence epilepsy (JAE) syndrome and patients having generalized tonic-clonic seizures (GTCS) with p-values of 0.003 and 0.0002, respectively (uncorrected for multiple comparisons). DNA sequence analysis of the INHA gene in 110 JAE/GTCS patients revealed three point mutations with possible damaging effects on inhibin function in three patients and the presence of a common ACTC haplotype (H1) with a possible dominant protective role conferred by the T allele of rs7588807 with respective p-values of 0.0005 and 0.0014. SIGNIFICANCE The preceding findings suggest that INHA could be a novel candidate susceptibility gene involved in the pathogenesis of JAE or AE associated with GTCS.
Collapse
Affiliation(s)
- Ozlem Yalçin
- Molecular Biology and Genetics, Boğaziçi University, Istanbul, Turkey
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | |
Collapse
|
27
|
Ludwig A, Ziegenhorn K, Empting S, Meissner T, Marquard J, Holl R, Mohnike K. Glucose metabolism and neurological outcome in congenital hyperinsulinism. Semin Pediatr Surg 2011; 20:45-9. [PMID: 21186004 DOI: 10.1053/j.sempedsurg.2010.10.005] [Citation(s) in RCA: 31] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/11/2022]
Abstract
Advances in imaging and surgical techniques allow a complete cure for children with focal-type congenital hyperinsulinism (CHI). In contrast, management of diffuse-type CHI remains a matter of controversy. To prevent hypoglycemic brain damage, extensive surgery has been recommended in the past, resulting in diabetes. On the basis of 2 data sets of patients with congenital hyperinsulinism, the German registry for CHI with 235 patients (ages 1 day to 19 years) and the diabetes treatment register (Diabetes Patienten-Verlaufsdokumentationssystem initiative), a follow-up study was initiated for diabetes mellitus and the intellectual and physical development as well as motor function. In our ongoing study, we investigated 20 patients with CHI (12 male, mean ages 9.9 years). Six of 20 patients had undergone subtotal pancreatectomy. In early infantile development (0-3 years) we observed a trend to motor and speech delay. In early childhood (2.5-7 years) there appeared a trend to an advantage of results of nonverbal tasks compared with verbal tasks. Before 1990 most patients (∼75%) were treated by subtotal pancreatectomy; since 2000, a more conservative approach is obvious (4/68). All patients with diabetes (n = 25) developed the condition after undergoing subtotal pancreatectomy. No spontaneous manifestation of diabetes was noted before adulthood. There was a wide range of age (0-17.7 years) at manifestation indicating a long period during which glucose tolerance is compensated. Compared with >40.000 children with type 1 diabetes mellitus from the Diabetes Patienten-Verlaufsdokumentationssystem registry, we found significant differences with a tendency for being overweight as well as small stature. Mean daily insulin dose and HbA1c was comparable in both groups.
Collapse
Affiliation(s)
- Anja Ludwig
- Department of Pediatrics, O. v. Guericke University, Magdeburg, Germany.
| | | | | | | | | | | | | | | |
Collapse
|
28
|
Pérez Errazquin F, Sempere Fernández J, García Martín G, Chamorro Muñoz M, Romero Acebal M. Hyperinsulinism and hyperammonaemia syndrome and severe myoclonic epilepsy of infancy. NEUROLOGÍA (ENGLISH EDITION) 2011. [DOI: 10.1016/s2173-5808(11)70052-9] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/16/2022] Open
|
29
|
Abstract
The hyperinsulinism/hyperammonemia (HI/HA) syndrome is the second most common form of congenital hyperinsulinism (HI). Children affected by this syndrome have both fasting and protein sensitive hypoglycemia combined with persistently elevated ammonia levels. Gain of function mutations in the mitochondrial enzyme glutamate dehydrogenase (GDH) are responsible for the HI/HA syndrome. GDH is expressed in liver, kidney, brain, and pancreatic beta-cells. Patients with the HI/HA syndrome have an increased frequency of generalized seizures, especially absence-type seizures, in the absence of hypoglycemia. The hypoglycemia of the HI/HA syndrome is well controlled with diazoxide, a KATP channel agonist. GDH has also been implicated in another form of HI, short-chain 3-hydroxyacyl-CoA dehydrogenase (SCHAD) deficiency associated HI. The HI/HA syndrome provides a rare example of an inborn error of intermediary metabolism in which the effect of the mutation on enzyme activity is a gain of function.
Collapse
Affiliation(s)
- Andrew A Palladino
- The Children's Hospital of Philadelphia, Division of Endocrinology and Diabetes, University of Pennsylvania, School of Medicine, Philadelphia, PA 19104, USA.
| | | |
Collapse
|
30
|
Abstract
Epileptic encephalopathies presenting in early life present a diagnostic and therapeutic challenge. These disorders present with multiple seizure types that are treatment resistant and associated with significant abnormalities on electroencephalographic studies. The underlying etiology in many cases may be related to an inborn error of metabolism. Efforts to establish the specific diagnosis of a genetic defect or an inborn error of metabolism often results in requests for a vast array of biochemical and molecular tests leading to an expensive workup. In this review, we present the clinician with information that provides a rationale for a selective and nuanced approach to biochemical assays, and initial treatment strategies while waiting for a specific diagnosis to be established. A careful consideration of the presentation, identification of potentially treatable conditions, and consultation with the biochemical genetics laboratory can lead to a greater measure of success while limiting cost overruns. Such a targeted approach is hoped will lead to an early diagnosis and appropriate interventions.
Collapse
|
31
|
Kapoor RR, Flanagan SE, Fulton P, Chakrapani A, Chadefaux B, Ben-Omran T, Banerjee I, Shield JP, Ellard S, Hussain K. Hyperinsulinism-hyperammonaemia syndrome: novel mutations in the GLUD1 gene and genotype-phenotype correlations. Eur J Endocrinol 2009; 161:731-5. [PMID: 19690084 PMCID: PMC2761810 DOI: 10.1530/eje-09-0615] [Citation(s) in RCA: 63] [Impact Index Per Article: 4.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 07/20/2009] [Accepted: 08/09/2009] [Indexed: 12/14/2022]
Abstract
BACKGROUND Activating mutations in the GLUD1 gene (which encodes for the intra-mitochondrial enzyme glutamate dehydrogenase, GDH) cause the hyperinsulinism-hyperammonaemia (HI/HA) syndrome. Patients present with HA and leucine-sensitive hypoglycaemia. GDH is regulated by another intra-mitochondrial enzyme sirtuin 4 (SIRT4). Sirt4 knockout mice demonstrate activation of GDH with increased amino acid-stimulated insulin secretion. OBJECTIVES To study the genotype-phenotype correlations in patients with GLUD1 mutations. To report the phenotype and functional analysis of a novel mutation (P436L) in the GLUD1 gene associated with the absence of HA. Patients and methods Twenty patients with HI from 16 families had mutational analysis of the GLUD1 gene in view of HA (n=19) or leucine sensitivity (n=1). Patients negative for a GLUD1 mutation had sequence analysis of the SIRT4 gene. Functional analysis of the novel P436L GLUD1 mutation was performed. RESULTS Heterozygous missense mutations were detected in 15 patients with HI/HA, 2 of which are novel (N410D and D451V). In addition, a patient with a normal serum ammonia concentration (21 micromol/l) was heterozygous for a novel missense mutation P436L. Functional analysis of this mutation confirms that it is associated with a loss of GTP inhibition. Seizure disorder was common (43%) in our cohort of patients with a GLUD1 mutation. No mutations in the SIRT4 gene were identified. CONCLUSION Patients with HI due to mutations in the GLUD1 gene may have normal serum ammonia concentrations. Hence, GLUD1 mutational analysis may be indicated in patients with leucine sensitivity; even in the absence of HA. A high frequency of epilepsy (43%) was observed in our patients with GLUD1 mutations.
Collapse
Affiliation(s)
| | - Sarah E Flanagan
- Developmental Endocrinology Research Group, Molecular Genetics UnitLondon Centre for Paediatric Endocrinology and Metabolism, Great Ormond Street Hospital for Children NHS Trust, and The Institute of Child Health, University College London30 Guilford Street, London, WC1N 1EHUK
| | - Piers Fulton
- Developmental Endocrinology Research Group, Molecular Genetics UnitLondon Centre for Paediatric Endocrinology and Metabolism, Great Ormond Street Hospital for Children NHS Trust, and The Institute of Child Health, University College London30 Guilford Street, London, WC1N 1EHUK
| | - Anupam Chakrapani
- Peninsula Medical SchoolInstitute of Biomedical and Clinical ScienceExeter, EX2 5DWUK
| | - Bernadette Chadefaux
- Department of Inherited Metabolic DisordersBirmingham Children's HospitalBirmingham, B4 6NHUK
| | - Tawfeg Ben-Omran
- Metabolic Biochemistry Hôpital Necker –Enfants MaladesUniversité Paris DescartesParisFrance
| | - Indraneel Banerjee
- Clinical and Metabolic Genetics, Department of PediatricsHamad Medical Corporation and Weil-Cornell Medical CollegeDohaQatar
| | - Julian P Shield
- Department of Paediatric EndocrinologyRoyal Manchester Children's Hospital and Alder Hey Children's HospitalManchester, M27 4HAUK
| | - Sian Ellard
- Developmental Endocrinology Research Group, Molecular Genetics UnitLondon Centre for Paediatric Endocrinology and Metabolism, Great Ormond Street Hospital for Children NHS Trust, and The Institute of Child Health, University College London30 Guilford Street, London, WC1N 1EHUK
| | | |
Collapse
|
32
|
Wolf NI, García-Cazorla A, Hoffmann GF. Epilepsy and inborn errors of metabolism in children. J Inherit Metab Dis 2009; 32:609. [PMID: 19642011 DOI: 10.1007/s10545-009-1171-3] [Citation(s) in RCA: 25] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 02/12/2009] [Revised: 05/18/2009] [Accepted: 05/19/2009] [Indexed: 10/20/2022]
Abstract
Epilepsy is a frequent symptom in inborn errors of metabolism, with virtually no specific seizure types or EEG signatures. It is most important to look quickly for those few inborn errors of metabolism in which specific therapies such as supplementation of cofactors or diets can make all the difference. If these investigations remain negative, epilepsy has to be treated with conventional antiepileptic drugs. Still, epilepsy is a potentially treatable symptom of many inborn errors of metabolism, and optimal treatment is of great importance for patients and their families.
Collapse
Affiliation(s)
- N I Wolf
- Department of Child Neurology, VU University Medical Center (VUMC), Postbus 7057, 1007 MB, Amsterdam, The Netherlands.
| | - A García-Cazorla
- Department of Neurology, Hospital Sant Joan de Déu, Barcelona, and Centre for Biomedical Research on Rare Diseases (CIBER-ER), Instituto de Salud Carlos III, Barcelona, Spain
| | - G F Hoffmann
- University Children's Hospital Heidelberg, Heidelberg, Germany
| |
Collapse
|
33
|
Bahi-Buisson N, Roze E, Dionisi C, Escande F, Valayannopoulos V, Feillet F, Heinrichs C, Chadefaux-Vekemans B, Dan B, de Lonlay P. Neurological aspects of hyperinsulinism-hyperammonaemia syndrome. Dev Med Child Neurol 2008; 50:945-9. [PMID: 19046187 DOI: 10.1111/j.1469-8749.2008.03114.x] [Citation(s) in RCA: 75] [Impact Index Per Article: 4.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 01/25/2023]
Abstract
Hyperinsulinism-hyperammonaemia syndrome (HHS) is a rare cause of congenital hyperinsulinism, due to missense mutations in the GLUD1 gene, resulting in glutamate dehydrogenase (GDH) overactivity. The aim of this study was to document the spectrum of neurological disturbances associated with HHS and to identify possible phenotype-genotype correlations. We retrospectively analyzed the neurological outcomes of 22 consecutive patients (12 males, 10 females) aged from 18 months to 40 years and diagnosed with HHS. We analyzed demographic and clinical features and neuroradiological, biochemical, and genetic findings. Fourteen patients had childhood-onset epilepsy. Learning disability was found in 17 patients. Two patients had pyramidal involvement and one had generalized dystonia. Seizures were observed in 11 of 19 patients with documented GLUD1 mutations, and nine of these 11 patients had a mutation in the guanosine triphosphate (GTP) binding site. Our data demonstrate that neurological disorders in HHS are more frequent than previously thought and might suggest that mutations in the GTP binding site of GDH could be associated with more frequent epilepsy.
Collapse
Affiliation(s)
- Nadia Bahi-Buisson
- Department of Paediatric Neurology and Metabolic Diseases, Necker Children's Hospital, Paris V University, Paris, France.
| | | | | | | | | | | | | | | | | | | |
Collapse
|