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Falsaperla R, Sciacca M, Collotta AD, Tardino LG, Marino S, Marino SD, Privitera GF, Vitaliti G, Ruggieri M. PYRIDOXINE-dependent epilepsy (PDE): An observational study of neonatal cases on the role of pyridoxine in patients treated with standard anti-seizure medications. Seizure 2024; 118:156-163. [PMID: 38735085 DOI: 10.1016/j.seizure.2024.04.012] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/18/2023] [Revised: 04/09/2024] [Accepted: 04/12/2024] [Indexed: 05/14/2024] Open
Abstract
BACKGROUND The main objective of this study was to evaluate the neurological consequences of delayed pyridoxine administration in patients diagnosed with Pyridoxin Dependent Epilepsies (PDE). MATERIALS AND METHODS We reviewed 29 articles, comprising 52 genetically diagnosed PDE cases, ensuring data homogeneity. Three additional cases were included from the General Pediatric Operative Unit of San Marco Hospital. Data collection considered factors like age at the first seizure's onset, EEG reports, genetic analyses, and more. Based on the response to first-line antiseizure medications, patients were categorized into four distinct groups. Follow-up evaluations employed various scales to ascertain neurological, cognitive, and psychomotor developments. RESULTS Our study includes 55 patients (28 males and 27 females), among whom 15 were excluded for the lack of follow-up data. 21 patients were categorized as "Responder with Relapse", 11 as "Resistant", 6 as "Pyridoxine First Approach", and 2 as "Responders". The neurological outcome revealed 37,5 % with no neurological effects, 37,5 % showed complications in two developmental areas, 15 % in one, and 10 % in all areas. The statistical analysis highlighted a positive correlation between the time elapsed from the administration of pyridoxine after the first seizure and worse neurological outcomes. On the other hand, a significant association was found between an extended latency period (that is, the time that elapsed between the onset of the first seizure and its recurrence) and worse neurological outcomes in patients who received an unfavorable score on the neurological evaluation noted in a subsequent follow-up. CONCLUSIONS The study highlights the importance of early recognition and intervention in PDE. Existing medical protocols frequently overlook the timely diagnosis of PDE. Immediate administration of pyridoxine, guided by a swift diagnosis in the presence of typical symptoms, might improve long-term neurological outcomes, and further studies should evaluate the outcome of PDE neonates promptly treated with Pyridoxine.
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Affiliation(s)
- Raffaele Falsaperla
- General Pediatrics and Pediatric Emergency Department, "Policlinico G.Rodolico-San Marco" University Hospital, University of Catania, 95100 Catania, Italy; Unit of Neonatal Intensive Care and Neonatology, Policlinico "G. Rodolico-San Marco" University Hospital, University of Catania, 95100 Catania, Italy.
| | - Monica Sciacca
- General Pediatrics and Pediatric Emergency Department, "Policlinico G.Rodolico-San Marco" University Hospital, University of Catania, 95100 Catania, Italy
| | - Ausilia Desiree Collotta
- General Pediatrics and Pediatric Emergency Department, "Policlinico G.Rodolico-San Marco" University Hospital, University of Catania, 95100 Catania, Italy
| | - Lucia Giovanna Tardino
- General Pediatrics and Pediatric Emergency Department, "Policlinico G.Rodolico-San Marco" University Hospital, University of Catania, 95100 Catania, Italy
| | - Silvia Marino
- General Pediatrics and Pediatric Emergency Department, "Policlinico G.Rodolico-San Marco" University Hospital, University of Catania, 95100 Catania, Italy
| | - Simona Domenica Marino
- General Pediatrics and Pediatric Emergency Department, "Policlinico G.Rodolico-San Marco" University Hospital, University of Catania, 95100 Catania, Italy
| | - Greta Francesca Privitera
- Bioinformatics Unit, Department of Clinical and Experimental Medicine, University of Catania, Catania, Italy
| | - Giovanna Vitaliti
- General Pediatrics and Pediatric Emergency Department, "Policlinico G.Rodolico-San Marco" University Hospital, University of Catania, 95100 Catania, Italy.
| | - Martino Ruggieri
- Department of Child and Experimental Medicine, Section of Paediatrics and Child Neuropsychiatry, University of Catania, Italy
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Yan J, Wu J, Xu M, Wang M, Guo W. Disrupted de novo pyrimidine biosynthesis impairs adult hippocampal neurogenesis and cognition in pyridoxine-dependent epilepsy. SCIENCE ADVANCES 2024; 10:eadl2764. [PMID: 38579001 PMCID: PMC10997211 DOI: 10.1126/sciadv.adl2764] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/09/2023] [Accepted: 03/04/2024] [Indexed: 04/07/2024]
Abstract
Despite seizure control by early high-dose pyridoxine (vitamin B6) treatment, at least 75% of pyridoxine-dependent epilepsy (PDE) patients with ALDH7A1 mutation still suffer from intellectual disability. It points to a need for additional therapeutic interventions for PDE beyond pyridoxine treatment, which provokes us to investigate the mechanisms underlying the impairment of brain hemostasis by ALDH7A1 deficiency. In this study, we show that ALDH7A1-deficient mice with seizure control exhibit altered adult hippocampal neurogenesis and impaired cognitive functions. Mechanistically, ALDH7A1 deficiency leads to the accumulation of toxic lysine catabolism intermediates, α-aminoadipic-δ-semialdehyde and its cyclic form, δ-1-piperideine-6-carboxylate, which in turn impair de novo pyrimidine biosynthesis and inhibit NSC proliferation and differentiation. Notably, supplementation of pyrimidines rescues abnormal neurogenesis and cognitive impairment in ALDH7A1-deficient adult mice. Therefore, our findings not only define the important role of ALDH7A1 in the regulation of adult hippocampal neurogenesis but also provide a potential therapeutic intervention to ameliorate the defective mental capacities in PDE patients with seizure control.
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Affiliation(s)
- Jianfei Yan
- State Key Laboratory for Molecular and Developmental Biology, Institute of Genetics and Developmental Biology, Chinese Academy of Sciences, Beijing 100101, China
- University of Chinese Academy of Sciences, Beijing 100093, China
| | - Junjie Wu
- State Key Laboratory for Molecular and Developmental Biology, Institute of Genetics and Developmental Biology, Chinese Academy of Sciences, Beijing 100101, China
- University of Chinese Academy of Sciences, Beijing 100093, China
| | - Mingyue Xu
- State Key Laboratory for Molecular and Developmental Biology, Institute of Genetics and Developmental Biology, Chinese Academy of Sciences, Beijing 100101, China
- University of Chinese Academy of Sciences, Beijing 100093, China
| | - Min Wang
- State Key Laboratory for Molecular and Developmental Biology, Institute of Genetics and Developmental Biology, Chinese Academy of Sciences, Beijing 100101, China
| | - Weixiang Guo
- State Key Laboratory for Molecular and Developmental Biology, Institute of Genetics and Developmental Biology, Chinese Academy of Sciences, Beijing 100101, China
- University of Chinese Academy of Sciences, Beijing 100093, China
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Chang FM. Update current understanding of neurometabolic disorders related to lysine metabolism. Epilepsy Behav 2023; 146:109363. [PMID: 37499576 DOI: 10.1016/j.yebeh.2023.109363] [Citation(s) in RCA: 2] [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: 02/26/2023] [Revised: 07/14/2023] [Accepted: 07/14/2023] [Indexed: 07/29/2023]
Abstract
Lysine, as an essential amino acid, predominantly undergoes metabolic processes through the saccharopine pathway, whereas a smaller fraction follows the pipecolic acid pathway. Although the liver is considered the primary organ for lysine metabolism, it is worth noting that lysine catabolism also takes place in other tissues and organs throughout the body, including the brain. Enzyme deficiency caused by pathogenic variants in its metabolic pathway may lead to a series of neurometabolic diseases, among which glutaric aciduria type 1 and pyridoxine-dependent epilepsy have the most significant clinical manifestations. At present, through research, we have a deeper understanding of the multiple pathophysiological mechanisms related to these diseases, including intracerebral accumulation of neurotoxic metabolites, imbalance between GABAergic and glutamatergic neurotransmission, energy deprivation due to metabolites, and the dysfunction of antiquitin. Because of the complexity of these diseases, their clinical manifestations are also diverse. The early implementation of lysine-restricted diets and supplementation with arginine and carnitine has reported positive impacts on the neurodevelopmental outcomes of patients. Presently, there is more robust evidence supporting the effectiveness of these treatments in glutaric aciduria type 1 compared with pyridoxine-dependent epilepsy.
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Affiliation(s)
- Fu-Man Chang
- Department of Pediatrics, Taitung MacKay Memorial Hospital, Taitung, Taiwan.
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Mastrangelo M, Gasparri V, Bernardi K, Foglietta S, Ramantani G, Pisani F. Epilepsy Phenotypes of Vitamin B6-Dependent Diseases: An Updated Systematic Review. CHILDREN 2023; 10:children10030553. [PMID: 36980111 PMCID: PMC10047402 DOI: 10.3390/children10030553] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/30/2023] [Revised: 03/12/2023] [Accepted: 03/13/2023] [Indexed: 03/17/2023]
Abstract
Background: Vitamin B6-dependent epilepsies include treatable diseases responding to pyridoxine or pyridoxal-5Iphosphate (ALDH7A1 deficiency, PNPO deficiency, PLP binding protein deficiency, hyperprolinemia type II and hypophosphatasia and glycosylphosphatidylinositol anchor synthesis defects). Patients and methods: We conducted a systematic review of published pediatric cases with a confirmed molecular genetic diagnosis of vitamin B6-dependent epilepsy according to PRISMA guidelines. Data on demographic features, seizure semiology, EEG patterns, neuroimaging, treatment, and developmental outcomes were collected. Results: 497 published patients fulfilled the inclusion criteria. Seizure onset manifested at 59.8 ± 291.6 days (67.8% of cases in the first month of life). Clonic, tonic-clonic, and myoclonic seizures accounted for two-thirds of the cases, while epileptic spasms were observed in 7.6%. Burst-suppression/suppression-burst represented the most frequently reported specific EEG pattern (14.4%), mainly in PLPB, ALDH7A1, and PNPO deficiency. Pyridoxine was administered to 312 patients (18.5% intravenously, 76.9% orally, 4.6% not specified), and 180 also received antiseizure medications. Pyridoxine dosage ranged between 1 and 55 mg/kg/die. Complete seizure freedom was achieved in 160 patients, while a significant seizure reduction occurred in 38. PLP, lysine-restricted diet, and arginine supplementation were used in a small proportion of patients with variable efficacy. Global developmental delay was established in 30.5% of a few patients in whom neurocognitive tests were performed. Conclusions: Despite the wide variability, the most frequent hallmarks of the epilepsy phenotype in patients with vitamin B6-dependent seizures include generalized or focal motor seizure semiology and a burst suppression/suppression burst pattern in EEG.
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Affiliation(s)
- Mario Mastrangelo
- Child Neurology and Psychiatry Unit, Department of Human Neurosciences, Sapienza University of Rome, 00185 Rome, Italy
- Department of Neuroscience/Mental Health, Azienda Ospedaliero-Universitaria Policlinico Umberto I, 00161 Rome, Italy
- Correspondence:
| | - Valentina Gasparri
- Child Neurology and Psychiatry Unit, Department of Human Neurosciences, Sapienza University of Rome, 00185 Rome, Italy
| | - Katerina Bernardi
- Child Neurology and Psychiatry Unit, Department of Human Neurosciences, Sapienza University of Rome, 00185 Rome, Italy
| | - Silvia Foglietta
- Child Neurology and Psychiatry Unit, Department of Human Neurosciences, Sapienza University of Rome, 00185 Rome, Italy
| | - Georgia Ramantani
- Department of Neuropediatrics, University Children’s Hospital Zurich and University of Zurich, 8032 Zurich, Switzerland
| | - Francesco Pisani
- Child Neurology and Psychiatry Unit, Department of Human Neurosciences, Sapienza University of Rome, 00185 Rome, Italy
- Department of Neuroscience/Mental Health, Azienda Ospedaliero-Universitaria Policlinico Umberto I, 00161 Rome, Italy
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Beutler M, Harnischfeger J, Weber MHW, Hahnel SR, Quack T, Blohm A, Ueberall ME, Timm T, Lochnit G, Rennar GA, Gallinger TL, Houhou H, Rahlfs S, Falcone FH, Becker K, Schlitzer M, Haeberlein S, Czermak P, Salzig D, Grevelding CG. Identification and characterisation of the tegument-expressed aldehyde dehydrogenase SmALDH_312 of Schistosoma mansoni, a target of disulfiram. Eur J Med Chem 2023; 251:115179. [PMID: 36948075 DOI: 10.1016/j.ejmech.2023.115179] [Citation(s) in RCA: 3] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/22/2022] [Revised: 01/17/2023] [Accepted: 01/31/2023] [Indexed: 02/12/2023]
Abstract
Schistosomiasis is an infectious disease caused by blood flukes of the genus Schistosoma and affects approximately 200 million people worldwide. Since Praziquantel (PZQ) is the only drug for schistosomiasis, alternatives are needed. By a biochemical approach, we identified a tegumentally expressed aldehyde dehydrogenase (ALDH) of S. mansoni, SmALDH_312. Molecular analyses of adult parasites showed Smaldh_312 transcripts in both genders and different tissues. Physiological and cell-biological experiments exhibited detrimental effects of the drug disulfiram (DSF), a known ALDH inhibitor, on larval and adult schistosomes in vitro. DSF also reduced stem-cell proliferation and caused severe tegument damage in treated worms. In silico-modelling of SmALDH_312 and docking analyses predicted DSF binding, which we finally confirmed by enzyme assays with recombinant SmALDH_312. Furthermore, we identified compounds of the Medicine for Malaria Venture (MMV) pathogen box inhibiting SmALDH_312 activity. Our findings represent a promising starting point for further development towards new drugs for schistosomiasis.
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Affiliation(s)
- Mandy Beutler
- Institute of Parasitology, BFS, Justus Liebig University Giessen, Germany
| | - Julie Harnischfeger
- Institute of Bioprocess Engineering and Pharmaceutical Technology, University of Applied Sciences Mittelhessen, Giessen, Germany
| | - Michael H W Weber
- Institute of Parasitology, BFS, Justus Liebig University Giessen, Germany
| | - Steffen R Hahnel
- Institute of Parasitology, BFS, Justus Liebig University Giessen, Germany
| | - Thomas Quack
- Institute of Parasitology, BFS, Justus Liebig University Giessen, Germany
| | - Ariane Blohm
- Institute of Parasitology, BFS, Justus Liebig University Giessen, Germany
| | - Monique E Ueberall
- Institute of Parasitology, BFS, Justus Liebig University Giessen, Germany; Institute of Bioprocess Engineering and Pharmaceutical Technology, University of Applied Sciences Mittelhessen, Giessen, Germany
| | - Thomas Timm
- Protein Analytics, Institute of Biochemistry, Justus Liebig University Giessen, Germany
| | - Günter Lochnit
- Protein Analytics, Institute of Biochemistry, Justus Liebig University Giessen, Germany
| | - Georg A Rennar
- Department of Pharmaceutical Chemistry, Philipps Universität Marburg, Germany, Germany
| | - Tom L Gallinger
- Department of Pharmaceutical Chemistry, Philipps Universität Marburg, Germany, Germany
| | - Hicham Houhou
- Institute of Parasitology, BFS, Justus Liebig University Giessen, Germany
| | - Stefan Rahlfs
- Institute for Biochemistry and Molecular Biology, Interdisciplinary Research Centre, Justus Liebig University, Germany
| | - Franco H Falcone
- Institute of Parasitology, BFS, Justus Liebig University Giessen, Germany
| | - Katja Becker
- Institute for Biochemistry and Molecular Biology, Interdisciplinary Research Centre, Justus Liebig University, Germany
| | - Martin Schlitzer
- Department of Pharmaceutical Chemistry, Philipps Universität Marburg, Germany, Germany
| | - Simone Haeberlein
- Institute of Parasitology, BFS, Justus Liebig University Giessen, Germany
| | - Peter Czermak
- Institute of Bioprocess Engineering and Pharmaceutical Technology, University of Applied Sciences Mittelhessen, Giessen, Germany
| | - Denise Salzig
- Institute of Bioprocess Engineering and Pharmaceutical Technology, University of Applied Sciences Mittelhessen, Giessen, Germany
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Jiao X, Gong P, Niu Y, Zhang Y, Yang Z. A Rare Presentation Characterized by Epileptic Spasms in ALDH7A1, Pyridox(am)ine-5′-Phosphate Oxidase, and PLPBP Deficiency. Front Genet 2022; 13:804461. [PMID: 35495162 PMCID: PMC9039010 DOI: 10.3389/fgene.2022.804461] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/29/2021] [Accepted: 03/07/2022] [Indexed: 11/25/2022] Open
Abstract
Objective: To analyze the clinical feature, treatment, and prognosis of epileptic spasms (ES) in vitamin B6–dependent epilepsy, including patients with pyridoxine-dependent epilepsy (PDE) caused by ALDH7A1 mutation, pyridox(am)ine-5′-phosphate oxidase (PNPO) deficiency, and PLPBP deficiency. Methods: We analyzed data from a cohort of 54 cases with PDE, 13 cases with PNPO deficiency, and 2 cases with PLPBP deficiency and looked for the presentation of ES among them. Results: A total of 11 patients with the seizure presentation of ES have been collected. Among them, four patients carried mutations in ALDH7A1, six carried mutations in PNPO, and the remaining one carried mutation in PLPBP. The analysis of this cohort identified nine cases presenting as infantile spasms distributed in the three diseases and two cases presenting as Ohtahara syndrome diagnosed with PDE and PNPO deficiency, respectively. In the PDE and PLPBP deficiency groups, seizures were controlled by pyridoxine monotherapy, and the remaining one had refractory seizures due to secondary brain atrophy. In the groups with PNPO deficiency, one patient showed seizure-free when treated by PLP combined with valproic acid, three still had infrequent seizures treated by PLP monotherapy or pyridoxine or PLP combined with other antiseizure medications, and two died. In two cases presenting as Ohtahara syndrome, after regular treatment, one showed seizure-free, the others showed a marked decrease in seizure frequency, and they both showed an improvement in EEG. Significance: ES might be a common form of seizures in PNPO deficiency, and EEG presented as hypsarrhythmia or a burst suppression pattern. It is difficult for pyridoxine to control frequent seizures caused by secondary brain injury. In our PNPO deficiency cohort, patients with infantile spasms did not respond better to PLP than pyridoxine. Timely and correct treatment could prevent the transformation of the child’s disease from Ohtahara syndrome and infantile spasms to subsequent epileptic encephalopathy or refractory epilepsy.
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Zimmern V, Minassian B, Korff C. A Review of Targeted Therapies for Monogenic Epilepsy Syndromes. Front Neurol 2022; 13:829116. [PMID: 35250833 PMCID: PMC8891748 DOI: 10.3389/fneur.2022.829116] [Citation(s) in RCA: 2] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/04/2021] [Accepted: 01/13/2022] [Indexed: 11/15/2022] Open
Abstract
Genetic sequencing technologies have led to an increase in the identification and characterization of monogenic epilepsy syndromes. This increase has, in turn, generated strong interest in developing “precision therapies” based on the unique molecular genetics of a given monogenic epilepsy syndrome. These therapies include diets, vitamins, cell-signaling regulators, ion channel modulators, repurposed medications, molecular chaperones, and gene therapies. In this review, we evaluate these therapies from the perspective of their clinical validity and discuss the future of these therapies for individual syndromes.
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Affiliation(s)
- Vincent Zimmern
- Division of Child Neurology, University of Texas Southwestern, Dallas, TX, United States
- *Correspondence: Vincent Zimmern
| | - Berge Minassian
- Division of Child Neurology, University of Texas Southwestern, Dallas, TX, United States
| | - Christian Korff
- Pediatric Neurology Unit, University Hospitals, Geneva, Switzerland
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Pyridoxine-Dependent Epilepsy and Antiquitin Deficiency Resulting in Neonatal-Onset Refractory Seizures. Brain Sci 2021; 12:brainsci12010065. [PMID: 35053812 PMCID: PMC8773593 DOI: 10.3390/brainsci12010065] [Citation(s) in RCA: 8] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/06/2021] [Revised: 12/25/2021] [Accepted: 12/29/2021] [Indexed: 12/29/2022] Open
Abstract
Pyridoxine-dependent epilepsy (PDE) is an autosomal recessive neurometabolic disorder due to a deficiency of α-aminoadipic semialdehyde dehydrogenase (mutation in ALDH7A1 gene), more commonly known as antiquitin (ATQ). ATQ is one of the enzymes involved in lysine oxidation; thus, its deficiency leads to the accumulation of toxic metabolites in body fluids. PDE is characterized by persistent, recurrent neonatal seizures that cannot be well controlled by antiepileptic drugs but are responsive clinically and electrographically to daily pyridoxine (vitamin B6) supplementation. Although the phenotypic spectrum distinguishes between typical and atypical, pyridoxine-dependent is true for each. Diagnosis may pose a challenge mainly due to the rarity of the disorder and the fact that seizures may not occur until childhood or even late adolescence. Moreover, patients may not demonstrate an obvious clinical or electroencephalography response to the initial dose of pyridoxine. Effective treatment requires lifelong pharmacologic supplements of pyridoxine, and dietary lysine restriction and arginine enrichment should improve prognosis and avoid developmental delay and intellectual disability. The purpose of this review is to summarize briefly the latest reports on the etiology, clinical symptoms, diagnosis, and management of patients suffering from pyridoxine-dependent epilepsy.
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Clinical and biochemical outcome of a patient with pyridoxine-dependent epilepsy treated by triple therapy (pyridoxine supplementation, lysine-restricted diet, and arginine supplementation). Acta Neurol Belg 2021; 121:1669-1675. [PMID: 33113107 DOI: 10.1007/s13760-020-01467-3] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/01/2019] [Accepted: 08/05/2020] [Indexed: 10/23/2022]
Abstract
Pyridoxine-dependent epilepsy (PDE) is a recessive genetic disease characterized by epileptic encephalopathy with therapeutic response to pharmacological doses of pyridoxine and resistance to anti-epileptic treatments. The recent discovery in 2006 of the genetic defect antiquitin (ALDH7A1, OMIM #266100) has helped to understand the underlying mechanism, which is the accumulation of neurotoxic intermediates in the lysine catabolic pathway. The goal of the new therapeutic approach, termed triple therapy (TT) (pyridoxine, lysine-restricted diet and arginine supplementation), is to improve epilepsy control and neurocognitive development in patients with PDE. We present the 3-year treatment outcome for a child with PDE on pyridoxine treatment (started at age 5 months), lysine-restricted diet (started at age 17 months) and arginine supplementation therapy (started at age 19 months). The TT was well-tolerated with good compliance. No adverse events were reported. We observed a neurodevelopmental improvement, significantly fewer seizures, and a reduction of pipecolic acid (PA) as a biomarker of the illness. Our results show an improving clinical evolution, supporting and extending previous studies reporting efficacy of TT.
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Cognitive and neurological outcome of patients in the Dutch pyridoxine-dependent epilepsy (PDE-ALDH7A1) cohort, a cross-sectional study. Eur J Paediatr Neurol 2021; 33:112-120. [PMID: 34153871 DOI: 10.1016/j.ejpn.2021.06.001] [Citation(s) in RCA: 10] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 11/08/2020] [Revised: 05/14/2021] [Accepted: 06/02/2021] [Indexed: 11/24/2022]
Abstract
BACKGROUND Pyridoxine monotherapy in PDE-ALDH7A1 often results in adequate seizure control, but neurodevelopmental outcome varies. Detailed long-term neurological outcome is unknown. Here we present the cognitive and neurological features of the Dutch PDE-ALDH7A1 cohort. METHODS Neurological outcome was assessed in 24 patients (age 1-26 years); classified as normal, complex minor neurological dysfunction (complex MND) or abnormal. Intelligence quotient (IQ) was derived from standardized IQ tests with five severity levels of intellectual disability (ID). MRI's and treatments were assessed. RESULTS Ten patients (42%) showed unremarkable neurological examination, 11 (46%) complex MND, and 3 (12%) cerebral palsy (CP). Minor coordination problems were identified in 17 (71%), fine motor disability in 11 (46%), posture/muscle tone deviancies in 11 (46%) and abnormal reflexes in 8 (33%). Six patients (25%) had an IQ > 85, 7 (29%) borderline, 7 (29%) mild, 3 (13%) moderate, and 1 severe ID. Cerebral ventriculomegaly on MRI was progressive in 11. Three patients showed normal neurologic exam, IQ, and MRI. Eleven patients were treated with pyridoxine only and 13 by additional lysine reduction therapy (LRT). LRT started at age <3 years demonstrated beneficial effect on IQ results in 3 patients. DISCUSSION Complex MND and CP occurred more frequently in PDE-ALDH7A1 (46% and 12%) than in general population (7% and 0.2%, Peters et al., 2011, Schaefer et al., 2008). Twenty-five percent had a normal IQ. Although LRT shows potential to improve outcomes, data are heterogeneous in small patient numbers. More research with longer follow-up via the International PDE Registry (www.pdeonline.org) is needed.
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La Mendola FMC, Timpanaro T, Caruso D, Garozzo MT, Presti S, Romano C, Praticò ER, Lombardo G, Zanghì A, Falsaperla R. ALDH7A1 Gene and Its Related Pyridoxine-Dependent Epilepsy. JOURNAL OF PEDIATRIC NEUROLOGY 2021. [DOI: 10.1055/s-0041-1728686] [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
AbstractDespite being classically reported as caused by mutations in solute carriers genes (SLC2A1), it has been recently shown that also mutations in ALDH7A1 can cause pyridoxine-dependent epilepsy (PDE). ALDH7A1 is a gene encoding for the antiquitin, an enzyme that catalyzes the nicotinamide adenine dinucleotide-dependent dehydrogenation of L-α-aminoadipic semialdehyde/L-Δ1-piperideine 6-carboxylate. It is a highly treatable disorder, but nevertheless it is still not certain when to consider this diagnosis and how to test for it. It is possible to identify a classical form and an atypical one of PDE associated with more than 70 mutations of ALDH7A1 gene. The typical form is characterized by the onset of seizures within the first month of life and can be treated with pyridoxine in monotherapy, as they are not responsive to traditional anticonvulsant therapy. The atypical forms are equally pyridoxine-dependent, but are characterized by a later onset of seizures, sometimes up to the age of 3 years. Several brain abnormalities have been associated with ALDH7A1 mutations. Seizure control is achieved by the administration of high-dose pyridoxine, which must be started in the patient as soon as possible. However, it has been observed that pyridoxine therapy does not prevent developmental delay in most cases; in these cases, it can be recommended and useful to supplement arginine with pyridoxine therapy associated with a dietary restriction of lysine.
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Affiliation(s)
| | - Tiziana Timpanaro
- Pediatrics Postgraduate Residency Program, Section of Pediatrics and Child Neuropsychiatry, Department of Clinical and Experimental Medicine, University of Catania, Catania, Italy
| | - Daniela Caruso
- 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
| | - Santiago Presti
- Pediatrics Postgraduate Residency Program, Section of Pediatrics and Child Neuropsychiatry, Department of Clinical and Experimental Medicine, University of Catania, Catania, Italy
| | - Catia Romano
- Italian Blind Union, Catania section, Catania, Italy
| | | | - Giulia Lombardo
- Pediatrics Postgraduate Residency Program, Section of Pediatrics and Child Neuropsychiatry, Department of Clinical and Experimental Medicine, University of Catania, Catania, Italy
| | - Antonio Zanghì
- Department of Medical and Surgical Sciences and Advanced Technology “G.F. Ingrassia,” University of Catania, 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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Shortall K, Djeghader A, Magner E, Soulimane T. Insights into Aldehyde Dehydrogenase Enzymes: A Structural Perspective. Front Mol Biosci 2021; 8:659550. [PMID: 34055881 PMCID: PMC8160307 DOI: 10.3389/fmolb.2021.659550] [Citation(s) in RCA: 69] [Impact Index Per Article: 23.0] [Reference Citation Analysis] [Abstract] [Key Words] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/27/2021] [Accepted: 04/28/2021] [Indexed: 12/30/2022] Open
Abstract
Aldehyde dehydrogenases engage in many cellular functions, however their dysfunction resulting in accumulation of their substrates can be cytotoxic. ALDHs are responsible for the NAD(P)-dependent oxidation of aldehydes to carboxylic acids, participating in detoxification, biosynthesis, antioxidant and regulatory functions. Severe diseases, including alcohol intolerance, cancer, cardiovascular and neurological diseases, were linked to dysfunctional ALDH enzymes, relating back to key enzyme structure. An in-depth understanding of the ALDH structure-function relationship and mechanism of action is key to the understanding of associated diseases. Principal structural features 1) cofactor binding domain, 2) active site and 3) oligomerization mechanism proved critical in maintaining ALDH normal activity. Emerging research based on the combination of structural, functional and biophysical studies of bacterial and eukaryotic ALDHs contributed to the appreciation of diversity within the superfamily. Herewith, we discuss these studies and provide our interpretation for a global understanding of ALDH structure and its purpose–including correct function and role in disease. Our analysis provides a synopsis of a common structure-function relationship to bridge the gap between the highly studied human ALDHs and lesser so prokaryotic models.
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Affiliation(s)
- Kim Shortall
- Department of Chemical Sciences, Bernal Institute, University of Limerick, Limerick, Ireland
| | - Ahmed Djeghader
- Department of Chemical Sciences, Bernal Institute, University of Limerick, Limerick, Ireland
| | - Edmond Magner
- Department of Chemical Sciences, Bernal Institute, University of Limerick, Limerick, Ireland
| | - Tewfik Soulimane
- Department of Chemical Sciences, Bernal Institute, University of Limerick, Limerick, Ireland
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13
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Ghatge MS, Al Mughram M, Omar AM, Safo MK. Inborn errors in the vitamin B6 salvage enzymes associated with neonatal epileptic encephalopathy and other pathologies. Biochimie 2021; 183:18-29. [PMID: 33421502 DOI: 10.1016/j.biochi.2020.12.025] [Citation(s) in RCA: 10] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/18/2020] [Revised: 12/28/2020] [Accepted: 12/30/2020] [Indexed: 12/28/2022]
Abstract
Pyridoxal 5'-phosphate (PLP), the active cofactor form of vitamin B6 is required by over 160 PLP-dependent (vitamin B6) enzymes serving diverse biological roles, such as carbohydrates, amino acids, hemes, and neurotransmitters metabolism. Three key enzymes, pyridoxal kinase (PL kinase), pyridoxine 5'-phosphate oxidase (PNPO), and phosphatases metabolize and supply PLP to PLP-dependent enzymes through the salvage pathway. In born errors in the salvage enzymes are known to cause inadequate levels of PLP in the cell, particularly in neuronal cells. The resulting PLP deficiency is known to cause or implicated in several pathologies, most notably seizures. One such disorder, PNPO-dependent neonatal epileptic encephalopathy (NEE) results from natural mutations in PNPO and leads to null or reduced enzymatic activity. NEE does not respond to conventional antiepileptic drugs but may respond to treatment with the B6 vitamers PLP and/or pyridoxine (PN). In born errors that lead to PLP deficiency in cells have also been reported in PL kinase, however, to date none has been associated with epilepsy or seizure. One such pathology is polyneuropathy that responds to PLP therapy. Phosphatase deficiency or hypophosphatasia disorder due to pathogenic mutations in alkaline phosphatase is known to cause seizures that respond to PN therapy. In this article, we review the biochemical features of in born errors pertaining to the salvage enzyme's deficiency that leads to NEE and other pathologies. We also present perspective on vitamin B6 treatment for these disorders, along with attempts to develop zebrafish model to study the NEE syndrome in vivo.
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Affiliation(s)
- Mohini S Ghatge
- Department of Medicinal Chemistry, School of Pharmacy, Virginia Commonwealth University, Richmond, VA, 23298, USA; Institute for Structural Biology, Drug Discovery, and Development, School of Pharmacy, Virginia Commonwealth University, Richmond, VA, 23298, USA
| | - Mohammed Al Mughram
- Department of Medicinal Chemistry, School of Pharmacy, Virginia Commonwealth University, Richmond, VA, 23298, USA; Institute for Structural Biology, Drug Discovery, and Development, School of Pharmacy, Virginia Commonwealth University, Richmond, VA, 23298, USA
| | - Abdelsattar M Omar
- Department of Pharmaceutical Chemistry, Faculty of Pharmacy, King Abdulaziz University, Alsulaymanyah, Jeddah, 21589, Saudi Arabia; Department of Pharmaceutical Chemistry, Faculty of Pharmacy, Al-Azhar University, Cairo, 11884, Egypt
| | - Martin K Safo
- Department of Medicinal Chemistry, School of Pharmacy, Virginia Commonwealth University, Richmond, VA, 23298, USA; Institute for Structural Biology, Drug Discovery, and Development, School of Pharmacy, Virginia Commonwealth University, Richmond, VA, 23298, USA.
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14
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Jiao X, Gong P, Wu Y, Zhang Y, Yang Z. Analysis of the Phenotypic Variability as Well as Impact of Early Diagnosis and Treatment in Six Affected Families With ALDH7A1 Deficiency. Front Genet 2021; 12:644447. [PMID: 33868381 PMCID: PMC8047191 DOI: 10.3389/fgene.2021.644447] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/21/2020] [Accepted: 03/15/2021] [Indexed: 11/13/2022] Open
Abstract
Objective To describe the clinical characteristics of 12 patients from six families with pyridoxine-dependent epilepsy (PDE) carrying ALDH7A1 mutations, and analyze the impact of early diagnosis and treatment, as well as possible genotype–phenotype relationship. Methods Clinical and genetics data of 12 patients were collected. Results Family 1–3 presented with symptoms in the neonatal period, while family 4-6 presented during early infancy. In the same family, the age of onset was similar. The focal motor seizure appeared in all patients. The affected identical twins from family 4 were diagnosed with infantile spasms. Mutation analysis identified nine different ALDH7A1 mutations among six families. The neurodevelopment of siblings in family 1 was mild delay and normal separately due to the minor difference of delayed diagnosis time. Siblings in family 2 showed severely delayed and normal development respectively due to the significant difference of a delayed diagnosis for 4 years. In family 5, although the difference of the delayed diagnosis time is up to 7 years, the nearly normal psychomotor development in both patients might be due to infrequent seizures before the delayed diagnosis. A severe phenotype exhibited in family 3, 4, and 6. The survived affected patients presented with severe developmental delay or refractory seizures and their twins or older sisters presented a similar clinical history and died in the early days of life. Mutation analysis showed D511N and IVS11 + 1G > A in family 3, V188A and exon1 deletion in family 4, and Y354C and exon 8–13 deletion in family 6. Conclusion Patients from the same family often have the same phenotype, including onset age and seizure type. Early treatment with pyridoxine and infrequent seizures showed positive relationship with prognosis. The deletion of exon 1 and exon 8–13 might be associated with the severe phenotype.
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Affiliation(s)
- Xianru Jiao
- Department of Pediatrics, Peking University First Hospital, Beijing, China
| | - Pan Gong
- Department of Pediatrics, Peking University First Hospital, Beijing, China
| | - Ye Wu
- Department of Pediatrics, Peking University First Hospital, Beijing, China
| | - Yuehua Zhang
- Department of Pediatrics, Peking University First Hospital, Beijing, China
| | - Zhixian Yang
- Department of Pediatrics, Peking University First Hospital, Beijing, China
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15
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Chan F, Liu J. Molecular regulation of brain metabolism underlying circadian epilepsy. Epilepsia 2021; 62 Suppl 1:S32-S48. [PMID: 33395505 DOI: 10.1111/epi.16796] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/22/2020] [Revised: 12/01/2020] [Accepted: 12/01/2020] [Indexed: 12/13/2022]
Abstract
Extensive study has demonstrated that epilepsy occurs with greater frequency at certain times in the 24-h cycle. Although these findings implicate an overlap between the circadian rhythm and epilepsy, the molecular and cellular mechanisms underlying this circadian regulation are poorly understood. Because the 24-h rhythm is generated by the circadian molecular system, it is not surprising that this system comprised of many circadian genes is implicated in epilepsy. We summarized evidence in the literature implicating various circadian genes such as Clock, Bmal1, Per1, Rev-erb⍺, and Ror⍺ in epilepsy. In various animal models of epilepsy, the circadian oscillation and the steady-state level of these genes are disrupted. The downstream pathway of these genes involves a large number of metabolic pathways associated with epilepsy. These pathways include pyridoxal metabolism, the mammalian target of rapamycin pathway, and the regulation of redox state. We propose that disruption of these metabolic pathways could mediate the circadian regulation of epilepsy. A greater understanding of the cellular and molecular mechanism of circadian regulation of epilepsy would enable us to precisely target the circadian disruption in epilepsy for a novel therapeutic approach.
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Affiliation(s)
- Felix Chan
- Department of Molecular Biology, Cell Biology, and Biochemistry, Brown University, Providence, Rhode Island, USA
| | - Judy Liu
- Department of Molecular Biology, Cell Biology, and Biochemistry, Brown University, Providence, Rhode Island, USA.,Department of Neurology, Warren Alpert Medical School, Brown University, Providence, Rhode Island, USA
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16
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Coughlin CR, Tseng LA, Abdenur JE, Ashmore C, Boemer F, Bok LA, Boyer M, Buhas D, Clayton PT, Das A, Dekker H, Evangeliou A, Feillet F, Footitt EJ, Gospe SM, Hartmann H, Kara M, Kristensen E, Lee J, Lilje R, Longo N, Lunsing RJ, Mills P, Papadopoulou MT, Pearl PL, Piazzon F, Plecko B, Saini AG, Santra S, Sjarif DR, Stockler-Ipsiroglu S, Striano P, Van Hove JLK, Verhoeven-Duif NM, Wijburg FA, Zuberi SM, van Karnebeek CDM. Consensus guidelines for the diagnosis and management of pyridoxine-dependent epilepsy due to α-aminoadipic semialdehyde dehydrogenase deficiency. J Inherit Metab Dis 2021; 44:178-192. [PMID: 33200442 DOI: 10.1002/jimd.12332] [Citation(s) in RCA: 40] [Impact Index Per Article: 13.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 08/14/2020] [Revised: 10/21/2020] [Accepted: 11/13/2020] [Indexed: 12/19/2022]
Abstract
Pyridoxine-dependent epilepsy (PDE-ALDH7A1) is an autosomal recessive condition due to a deficiency of α-aminoadipic semialdehyde dehydrogenase, which is a key enzyme in lysine oxidation. PDE-ALDH7A1 is a developmental and epileptic encephalopathy that was historically and empirically treated with pharmacologic doses of pyridoxine. Despite adequate seizure control, most patients with PDE-ALDH7A1 were reported to have developmental delay and intellectual disability. To improve outcome, a lysine-restricted diet and competitive inhibition of lysine transport through the use of pharmacologic doses of arginine have been recommended as an adjunct therapy. These lysine-reduction therapies have resulted in improved biochemical parameters and cognitive development in many but not all patients. The goal of these consensus guidelines is to re-evaluate and update the two previously published recommendations for diagnosis, treatment, and follow-up of patients with PDE-ALDH7A1. Members of the International PDE Consortium initiated evidence and consensus-based process to review previous recommendations, new research findings, and relevant clinical aspects of PDE-ALDH7A1. The guideline development group included pediatric neurologists, biochemical geneticists, clinical geneticists, laboratory scientists, and metabolic dieticians representing 29 institutions from 16 countries. Consensus guidelines for the diagnosis and management of patients with PDE-ALDH7A1 are provided.
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Affiliation(s)
- Curtis R Coughlin
- Section of Clinical Genetics and Metabolism, Department of Pediatrics, University of Colorado Anschutz Medical Campus, Aurora, Colorado, USA
| | - Laura A Tseng
- Department of Pediatrics Emma Children's Hospital, Amsterdam University Medical Centre, Amsterdam, The Netherlands
| | - Jose E Abdenur
- Division of Metabolic Disorders, CHOC Children's Hospital, Orange, California, USA
| | - Catherine Ashmore
- Birmingham Women's and Children's NHS Foundation Trust, Birmingham, UK
| | - François Boemer
- Department of Human Genetics, Centre Hospitalier Universitaire Sart-Tilman, Liège, Belgium
| | - Levinus A Bok
- Department of Pediatrics and Neonatology, Máxima Medical Center, Veldhoven, The Netherlands
| | - Monica Boyer
- Division of Metabolic Disorders, CHOC Children's Hospital, Orange, California, USA
| | - Daniela Buhas
- Division of Medical Genetics, Department of Specialized Medicine, Montreal Children's Hospital, McGill University Health Centre, Québec, Canada
| | - Peter T Clayton
- Genetics and Genomic Medicine, UCL Great Ormond Street Institute of Child Health, London, UK
| | - Anibh Das
- Clinic for Paediatric Kidney, Liver, and Metabolic Diseases, Hannover Medical School, Hannover, Germany
| | - Hanka Dekker
- VKS: Dutch Patient Organization for Metabolic Diseases, Zwolle, The Netherlands
| | - Athanasios Evangeliou
- Division of Child Neurology and Inherited Metabolic Disorders, 4th Department of Pediatrics, Aristotle University of Thessaloniki, General Hospital Papageorgiou, Thessaloniki, Greece
| | - François Feillet
- Reference Center for Inborn Errors of Metabolism, Pediatric Unit, University Hospital of Nancy, Nancy, France
- INSERM UMR S 1256, Nutrition, Genetics, and Environmental Risk Exposure (NGERE), Faculty of Medicine of Nancy, University of Lorraine, Nancy, France
| | - Emma J Footitt
- Department of Metabolic Paediatrics, Great Ormond Street Hospital, London, UK
| | - Sidney M Gospe
- Division of Pediatric Neurology, Departments of Neurology and Pediatrics, University of Washington, Seattle, Washington, USA
- Department of Pediatrics, Duke University, Durham, North Carolina, USA
| | - Hans Hartmann
- Clinic for Paediatric Kidney, Liver, and Metabolic Diseases, Hannover Medical School, Hannover, Germany
| | - Majdi Kara
- Department of Pediatrics, University of Tripoli, Tripoli, Libya
| | - Erle Kristensen
- National Management of Newborn Screening and Advanced Laboratory Diagnostics in Inborn Errors of Metabolism, Department of Children and Adolescent Medicine, Oslo University Hospital, Oslo, Norway
| | - Joy Lee
- Department of Metabolic Medicine, The Royal Children's Hospital, Melbourne, Victoria, Australia
| | - Rina Lilje
- Department of Children and Adolescent Medicine, Oslo University Hospital, Oslo, Norway
| | - Nicola Longo
- Division of Medical Genetics, Department of Pediatrics, University of Utah, Salt Lake City, Utah, USA
| | - Roelineke J Lunsing
- Department of Neurology, University Medical Center Groningen, University of Groningen, Groningen, The Netherlands
| | - Philippa Mills
- Genetics and Genomic Medicine, UCL Great Ormond Street Institute of Child Health, London, UK
| | - Maria T Papadopoulou
- Division of Child Neurology and Inherited Metabolic Disorders, 4th Department of Pediatrics, Aristotle University of Thessaloniki, General Hospital Papageorgiou, Thessaloniki, Greece
| | - Phillip L Pearl
- Division of Epilepsy and Clinical Neurophysiology, Department of Neurology, Boston Children's Hospital, Harvard Medical School, Boston, Massachusetts, USA
| | - Flavia Piazzon
- Neurometabolic Clinic, Children's Institute, University of Sao Paulo, Brazil
| | - Barbara Plecko
- Division of General Pediatrics, Department of Pediatrics and Adolescent Medicine, Medical University of Graz, Graz, Austria
| | - Arushi G Saini
- Pediatric Neurology Unit, Department of Pediatrics, Postgraduate Institute of Medical Education and Research, Chandigarh, India
| | - Saikat Santra
- Birmingham Women's and Children's NHS Foundation Trust, Birmingham, UK
| | - Damayanti R Sjarif
- Department of Child Health, Faculty of Medicine, Universitas Indonesia, Jakarta, Indonesia
| | - Sylvia Stockler-Ipsiroglu
- Division of Biochemical Genetics, BC Children's Hospital, University of British Columbia, Vancouver, British Columbia, Canada
| | - Pasquale Striano
- Pediatric Neurology and Muscular Diseases Unit, IRCCS "G. Gaslini" Institute, Genoa, Italy
- Department of Neurosciences, Rehabilitation, Ophthalmology, Genetics, Maternal and Child Health, University of Genova, Genoa, Italy
| | - Johan L K Van Hove
- Section of Clinical Genetics and Metabolism, Department of Pediatrics, University of Colorado Anschutz Medical Campus, Aurora, Colorado, USA
| | | | - Frits A Wijburg
- Department of Pediatrics Emma Children's Hospital, Amsterdam University Medical Centre, Amsterdam, The Netherlands
| | - Sameer M Zuberi
- Paediatric Neurosciences Research Group, Royal Hospital for Children & School of Medicine, University of Glasgow, Glasgow, UK
| | - Clara D M van Karnebeek
- Department of Pediatrics Emma Children's Hospital, Amsterdam University Medical Centre, Amsterdam, The Netherlands
- Department of Pediatrics, Amalia Children's Hospital, Radboud Centre for Mitochondrial Medicine, Radboud University Medical Center, Nijmegen, The Netherlands
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17
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Bassi G, Favalli N, Vuk M, Catalano M, Martinelli A, Trenner A, Porro A, Yang S, Tham CL, Moroglu M, Yue WW, Conway SJ, Vogt PK, Sartori AA, Scheuermann J, Neri D. A Single-Stranded DNA-Encoded Chemical Library Based on a Stereoisomeric Scaffold Enables Ligand Discovery by Modular Assembly of Building Blocks. ADVANCED SCIENCE (WEINHEIM, BADEN-WURTTEMBERG, GERMANY) 2020; 7:2001970. [PMID: 33240760 PMCID: PMC7675038 DOI: 10.1002/advs.202001970] [Citation(s) in RCA: 29] [Impact Index Per Article: 7.3] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 05/26/2020] [Revised: 08/17/2020] [Indexed: 06/11/2023]
Abstract
A versatile and Lipinski-compliant DNA-encoded library (DEL), comprising 366 600 glutamic acid derivatives coupled to oligonucleotides serving as amplifiable identification barcodes is designed, constructed, and characterized. The GB-DEL library, constructed in single-stranded DNA format, allows de novo identification of specific binders against several pharmaceutically relevant proteins. Moreover, hybridization of the single-stranded DEL with a set of known protein ligands of low to medium affinity coupled to a complementary DNA strand results in self-assembled selectable chemical structures, leading to the identification of affinity-matured compounds.
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Affiliation(s)
- Gabriele Bassi
- Department of Chemistry and Applied BiosciencesETH ZürichZürich8092Switzerland
| | - Nicholas Favalli
- Department of Chemistry and Applied BiosciencesETH ZürichZürich8092Switzerland
| | - Miriam Vuk
- Department of Chemistry and Applied BiosciencesETH ZürichZürich8092Switzerland
| | - Marco Catalano
- Department of Chemistry and Applied BiosciencesETH ZürichZürich8092Switzerland
| | - Adriano Martinelli
- Department of Chemistry and Applied BiosciencesETH ZürichZürich8092Switzerland
| | - Anika Trenner
- Institute of Molecular Cancer ResearchUniversity of ZürichZürich8006Switzerland
| | - Antonio Porro
- Institute of Molecular Cancer ResearchUniversity of ZürichZürich8006Switzerland
| | - Su Yang
- Scripps Research InstituteDepartment of Molecular MedicineLa JollaCA92037USA
| | - Chuin Lean Tham
- Structural Genomic Consortium (SGC)Nuffield Department of MedicineUniversity of OxfordOxfordOX1 2JDUK
| | - Mustafa Moroglu
- Department of ChemistryChemistry Research LaboratoryUniversity of OxfordMansfield RoadOxfordOX1 3TAUK
| | - Wyatt W. Yue
- Structural Genomic Consortium (SGC)Nuffield Department of MedicineUniversity of OxfordOxfordOX1 2JDUK
| | - Stuart J. Conway
- Department of ChemistryChemistry Research LaboratoryUniversity of OxfordMansfield RoadOxfordOX1 3TAUK
| | - Peter K. Vogt
- Scripps Research InstituteDepartment of Molecular MedicineLa JollaCA92037USA
| | | | - Jörg Scheuermann
- Department of Chemistry and Applied BiosciencesETH ZürichZürich8092Switzerland
| | - Dario Neri
- Department of Chemistry and Applied BiosciencesETH ZürichZürich8092Switzerland
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18
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Korasick DA, Tanner JJ. Impact of missense mutations in the ALDH7A1 gene on enzyme structure and catalytic function. Biochimie 2020; 183:49-54. [PMID: 32956737 DOI: 10.1016/j.biochi.2020.09.016] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/24/2020] [Revised: 09/05/2020] [Accepted: 09/15/2020] [Indexed: 12/21/2022]
Abstract
Certain mutations in the ALDH7A1 gene cause pyridoxine-dependent epilepsy (PDE), an autosomal recessive metabolic disease characterized by seizures, and in some cases, intellectual disability. The mutational spectrum of PDE is vast and includes over 70 missense mutations. This review summarizes the current state of biochemical and biophysical research on the impact of PDE missense mutations on the structure and catalytic activity of ALDH7A1. Paradoxically, some mutations that target active site residues have a relatively modest impact on structure and function, while those remote from the active site can have profound effects. For example, missense mutations targeting remote residues in oligomer interfaces tend to strongly impact catalytic function by inhibiting formation of the active tetramer. These results shows that it remains very difficult to predict the impact of missense mutations, even when the structure of the wild-type enzyme is known. Additional biophysical analyses of many more disease-causing mutations are needed to develop the rules for predicting the impact of genetic mutations on enzyme structure and catalytic function.
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Affiliation(s)
- David A Korasick
- Department of Biochemistry, University of Missouri, Columbia, MO, 65211, United States
| | - John J Tanner
- Department of Biochemistry, University of Missouri, Columbia, MO, 65211, United States; Department of Chemistry, University of Missouri, Columbia, MO, 65211, United States.
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19
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Laciak AR, Korasick DA, Gates KS, Tanner JJ. Structural analysis of pathogenic mutations targeting Glu427 of ALDH7A1, the hot spot residue of pyridoxine-dependent epilepsy. J Inherit Metab Dis 2020; 43:635-644. [PMID: 31652343 PMCID: PMC7182499 DOI: 10.1002/jimd.12184] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 09/10/2019] [Revised: 10/17/2019] [Accepted: 10/23/2019] [Indexed: 12/11/2022]
Abstract
Certain loss-of-function mutations in the gene encoding the lysine catabolic enzyme aldehyde dehydrogenase 7A1 (ALDH7A1) cause pyridoxine-dependent epilepsy (PDE). Missense mutations of Glu427, especially Glu427Gln, account for ~30% of the mutated alleles in PDE patients, and thus Glu427 has been referred to as a mutation hot spot of PDE. Glu427 is invariant in the ALDH superfamily and forms ionic hydrogen bonds with the nicotinamide ribose of the NAD+ cofactor. Here we report the first crystal structures of ALDH7A1 containing pathogenic mutations targeting Glu427. The mutant enzymes E427Q, Glu427Asp, and Glu427Gly were expressed in Escherichia coli and purified. The recombinant enzymes displayed negligible catalytic activity compared to the wild-type enzyme. The crystal structures of the mutant enzymes complexed with NAD+ were determined to understand how the mutations impact NAD+ binding. In the E427Q and E427G structures, the nicotinamide mononucleotide is highly flexible and lacks a defined binding pose. In E427D, the bound NAD+ adopts a "retracted" conformation in which the nicotinamide ring is too far from the catalytic Cys residue for hydride transfer. Thus, the structures revealed a shared mechanism for loss of function: none of the variants are able to stabilise the nicotinamide of NAD+ in the pose required for catalysis. We also show that these mutations reduce the amount of active tetrameric ALDH7A1 at the concentration of NAD+ tested. Altogether, our results provide the three-dimensional molecular structural basis of the most common pathogenic variants of PDE and implicate strong (ionic) hydrogen bonds in the aetiology of a human disease.
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Affiliation(s)
- Adrian R. Laciak
- Department of Chemistry, University of Missouri, Columbia, Missouri
| | - David A. Korasick
- Department of Biochemistry, University of Missouri, Columbia, Missouri
| | - Kent S. Gates
- Department of Chemistry, University of Missouri, Columbia, Missouri
- Department of Biochemistry, University of Missouri, Columbia, Missouri
| | - John J. Tanner
- Department of Chemistry, University of Missouri, Columbia, Missouri
- Department of Biochemistry, University of Missouri, Columbia, Missouri
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20
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Contestabile R, di Salvo ML, Bunik V, Tramonti A, Vernì F. The multifaceted role of vitamin B 6 in cancer: Drosophila as a model system to investigate DNA damage. Open Biol 2020; 10:200034. [PMID: 32208818 PMCID: PMC7125957 DOI: 10.1098/rsob.200034] [Citation(s) in RCA: 10] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/15/2022] Open
Abstract
A perturbed uptake of micronutrients, such as minerals and vitamins, impacts on different human diseases, including cancer and neurological disorders. Several data converge towards a crucial role played by many micronutrients in genome integrity maintenance and in the establishment of a correct DNA methylation pattern. Failure in the proper accomplishment of these processes accelerates senescence and increases the risk of developing cancer, by promoting the formation of chromosome aberrations and deregulating the expression of oncogenes. Here, the main recent evidence regarding the impact of some B vitamins on DNA damage and cancer is summarized, providing an integrated and updated analysis, mainly centred on vitamin B6. In many cases, it is difficult to finely predict the optimal vitamin rate that is able to protect against DNA damage, as this can be influenced by a given individual's genotype. For this purpose, a precious resort is represented by model organisms which allow limitations imposed by more complex systems to be overcome. In this review, we show that Drosophila can be a useful model to deeply understand mechanisms underlying the relationship between vitamin B6 and genome integrity.
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Affiliation(s)
- Roberto Contestabile
- Istituto Pasteur Italia-Fondazione Cenci Bolognetti and Dipartimento di Scienze Biochimiche 'A. Rossi Fanelli', Sapienza Università di Roma, P.le A. Moro, 5, 00185, Roma, Italy
| | - Martino Luigi di Salvo
- Istituto Pasteur Italia-Fondazione Cenci Bolognetti and Dipartimento di Scienze Biochimiche 'A. Rossi Fanelli', Sapienza Università di Roma, P.le A. Moro, 5, 00185, Roma, Italy
| | - Victoria Bunik
- Belozersky Institute of Physico-Chemical Biology, Lomonosov Moscow State University, Moscow 119991, Russia.,Faculty of Bioengineering and Bioinformatics, Lomonosov Moscow State University, Moscow 119991, Russia.,Sechenov Medical University, Sechenov University, 119048 Moscow, Russia
| | - Angela Tramonti
- Istituto Pasteur Italia-Fondazione Cenci Bolognetti and Dipartimento di Scienze Biochimiche 'A. Rossi Fanelli', Sapienza Università di Roma, P.le A. Moro, 5, 00185, Roma, Italy.,Istituto di Biologia e Patologia Molecolari, Consiglio Nazionale delle Ricerche, Pl.e A. Moro, 5, 00185 Roma, Italy
| | - Fiammetta Vernì
- Dipartimento di Biologia e Biotecnologie 'Charles Darwin', Sapienza Università di Roma, Pl.e A. Moro, 5, 00185 Roma, Italy
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21
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Abstract
Introduction: Vitamin B6 dependent epilepsies are a group of treatable diseases (ALDH7A1 deficiency, PNPO deficiency, PLP binding protein deficiency, hyperprolinaemia type II and hypophosphatasia and glycosylphosphatidylinositol anchor synthesis defects) responding to pyridoxine or pyridoxal-5I-phosphate. Areas covered: A critical review was conducted on the therapeutic management of all the reported patients with genetically confirmed diagnoses of diseases affecting vitamin B6 metabolism and presenting with pyridoxine or pyridoxal-5I-phosphate dependent-seizures. Data about safety and efficacy were analyzed as well as the management of supplementation with pyridoxine or pyridoxal-5I-phosphate both in the acute phases and in the maintenance therapies. The authors also analyzed alternative therapeutic strategies for ALDH7A1 deficiency (lysine-restricted diet, arginine supplementation, oligonucleotide antisense therapy, upstream inhibition of aminoadipic semialdehyde synthase). Expert opinion: The administration of pyridoxine or pyridoxal-5I-phosphate should be considered in all intractable seizures also beyond the first year of life. Lysine restricted diet and arginine supplementation should be introduced in all the confirmed ALDH7A1 deficient patients. Pre or post-natal supplementation with pyridoxine should be given in familial cases until an eventual molecular genetic disconfirmation. Minor data about alternative therapies are available for other disorders of vitamin B6 metabolism.
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Affiliation(s)
- Mario Mastrangelo
- Division of Child Neurology and Infantile Psychiatry, Department of Human Neurosciences, Sapienza University of Rome , Roma , Italy
| | - Serena Cesario
- Division of Child Neurology and Infantile Psychiatry, Department of Human Neurosciences, Sapienza University of Rome , Roma , Italy
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22
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Coughlin CR, Swanson MA, Spector E, Meeks NJ, Kronquist KE, Aslamy M, Wempe MF, van Karnebeek CD, Gospe SM, Aziz VG, Tsai BP, Gao H, Nagy PL, Hyland K, van Dooren SJ, Salomons GS, Van Hove JL. The genotypic spectrum of ALDH7A1 mutations resulting in pyridoxine dependent epilepsy: A common epileptic encephalopathy. J Inherit Metab Dis 2019; 42:353-361. [PMID: 30043187 PMCID: PMC6345606 DOI: 10.1002/jimd.12045] [Citation(s) in RCA: 39] [Impact Index Per Article: 7.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/09/2022]
Abstract
Pyridoxine dependent epilepsy (PDE) is a treatable epileptic encephalopathy characterized by a positive response to pharmacologic doses of pyridoxine. Despite seizure control, at least 75% of individuals have intellectual disability and developmental delay. Current treatment paradigms have resulted in improved cognitive outcomes emphasizing the importance of an early diagnosis. As genetic testing is increasingly accepted as first tier testing for epileptic encephalopathies, we aimed to provide a comprehensive overview of ALDH7A1 mutations that cause PDE. The genotypes, ethnic origin and reported gender was collected from 185 subjects with a diagnosis of PDE. The population frequency for the variants in this report and the existing literature were reviewed in the Genome Aggregation Database (gnomAD). Novel variants identified in population databases were also evaluated through in silico prediction software and select variants were over-expressed in an E.coli-based expression system to measure α-aminoadipic semialdehyde dehydrogenase activity and production of α-aminoadipic acid. This study adds 47 novel variants to the literature resulting in a total of 165 reported pathogenic variants. Based on this report, in silico predictions, and general population data, we estimate an incidence of approximately 1:64,352 live births. This report provides a comprehensive overview of known ALDH7A1 mutations that cause PDE, and suggests that PDE may be more common than initially estimated. Due to the relative high frequency of the disease, the likelihood of under-diagnosis given the wide clinical spectrum and limited awareness among clinicians as well as the cognitive improvement noted with early treatment, newborn screening for PDE may be warranted.
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Affiliation(s)
- Curtis R. Coughlin
- Section of Clinical Genetics and Metabolism, Department of Pediatrics, University of Colorado School of Medicine, Aurora, CO, USA
- These authors contributed equally to the manuscript
- Correspondence: Curtis Coughlin II,
| | - Michael A. Swanson
- Section of Clinical Genetics and Metabolism, Department of Pediatrics, University of Colorado School of Medicine, Aurora, CO, USA
- These authors contributed equally to the manuscript
| | - Elaine Spector
- Section of Clinical Genetics and Metabolism, Department of Pediatrics, University of Colorado School of Medicine, Aurora, CO, USA
- Molecular Genetics Laboratory, Department of Pathology and Laboratory Medicine, Children’s Hospital Colorado, Aurora, CO 80045, USA
| | - Naomi J.L. Meeks
- Section of Clinical Genetics and Metabolism, Department of Pediatrics, University of Colorado School of Medicine, Aurora, CO, USA
- Molecular Genetics Laboratory, Department of Pathology and Laboratory Medicine, Children’s Hospital Colorado, Aurora, CO 80045, USA
| | - Kathryn E. Kronquist
- Section of Clinical Genetics and Metabolism, Department of Pediatrics, University of Colorado School of Medicine, Aurora, CO, USA
- Molecular Genetics Laboratory, Department of Pathology and Laboratory Medicine, Children’s Hospital Colorado, Aurora, CO 80045, USA
| | - Mezhgan Aslamy
- Section of Clinical Genetics and Metabolism, Department of Pediatrics, University of Colorado School of Medicine, Aurora, CO, USA
| | - Michael F. Wempe
- School of Pharmacy, Department of Pharmaceutical Sciences, University of Colorado, Anschutz Medical Campus, Aurora, CO 80045, USA
| | - Clara D.M. van Karnebeek
- Department of Pediatrics and Clinical Genetics, Academic Medical Centre, 1105 AZ Amsterdam, The Netherlands
- Department of Pediatrics, Centre for Molecular Medicine and Therapeutics, University of British Columbia, Vancouver BC V5Z4H4, Canada
| | - Sidney M. Gospe
- Division of Pediatric Neurology, Departments of Neurology and Pediatrics, University of Washington, Seattle, WA, USA
- Seattle Children’s Research Institute, Seattle, WA, USA
| | | | | | - Hanlin Gao
- Fulgent Genetics, Temple City, CA, 91780, USA
| | - Peter L. Nagy
- Medical Neurogenetics Laboratories, LLC, Atlanta, GA, USA
| | - Keith Hyland
- Medical Neurogenetics Laboratories, LLC, Atlanta, GA, USA
| | - Silvy J.M. van Dooren
- Department of Clinical Chemistry, Metabolic Unit, VU University Medical Center & Amsterdam Neuroscience, Amsterdam, The Netherlands
| | - Gajja S. Salomons
- Department of Clinical Chemistry, Metabolic Unit, VU University Medical Center & Amsterdam Neuroscience, Amsterdam, The Netherlands
| | - Johan L.K. Van Hove
- Section of Clinical Genetics and Metabolism, Department of Pediatrics, University of Colorado School of Medicine, Aurora, CO, USA
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Toldo I, Bonardi CM, Bettella E, Polli R, Talenti G, Burlina A, Sartori S, Murgia A. Brain malformations associated to Aldh7a1 gene mutations: Report of a novel homozygous mutation and literature review. Eur J Paediatr Neurol 2018; 22:1042-1053. [PMID: 30005813 DOI: 10.1016/j.ejpn.2018.06.010] [Citation(s) in RCA: 14] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 02/09/2018] [Revised: 06/20/2018] [Accepted: 06/27/2018] [Indexed: 01/27/2023]
Abstract
BACKGROUND The ALDH7A1 gene is known to be responsible for autosomal recessive pyridoxine-dependent epilepsy (OMIM 266100). The phenotypic spectrum of ALDH7A1 mutations is very heterogeneous ranging from refractory epilepsy and neurodevelopmental delay, to multisystem neonatal disorder. AIM The present study aims at describing the phenotype associated with a novel homozygous ALDH7A1 mutation and the spectrum of brain malformations associated with pyridoxine-dependent epilepsy. METHODS We conducted a literature review on the Internet database Pubmed (up to November 2017) searching for ALDH7A1 mutations associated with brain malformations and brain MRI findings. RESULTS We present the case of two siblings, children of related parents. The proband presented neonatal focal seizures not responding to conventional antiepileptic drugs. Electroencephalography showed a suppression burst pattern and several multifocal ictal patterns, responsive to pyridoxine. Brain MRI was normal. Molecular analysis by targeted next-generation sequencing panel for epileptic encephalopathy disclosed a homozygous missense mutation of ALDH7A1. The same mutation was then found in a stored sample of DNA from peripheral blood of an older sister dead 3 years earlier. This girl presented a complex brain malformation diagnosed with a foetal MRI and had neonatal refractory seizures with suppression burst pattern. She died at 6 months of age. LITERATURE REVIEW The brain abnormalities most frequently reported in pyridoxine-dependent epilepsy include: agenesia/hypoplasia of the corpus callosum, not specific white matter abnormalities, large cisterna magna, ventriculomegaly, haemorrhages, cerebellum hypoplasia/dysplasia, and, more rarely, dysplasia of the brainstem and hydrocephalus. DISCUSSION AND CONCLUSIONS ALDH7A1 mutations have been associated to different brain abnormalities, documented by MRI only in few cases. The study cases expand the clinical spectrum of ALDH7A1 associated conditions, suggesting to look for ALDH7A1 mutations not only in classical phenotypes but also in patients with brain malformations, mainly if there is a response to a pyridoxine trial.
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Affiliation(s)
- Irene Toldo
- Department of Woman's and Child's Health, University Hospital of Padua, Italy.
| | | | - Elisa Bettella
- Department of Woman's and Child's Health, University Hospital of Padua, Italy.
| | - Roberta Polli
- Department of Woman's and Child's Health, University Hospital of Padua, Italy.
| | - Giacomo Talenti
- Department of Neurosciences, University Hospital of Padua, Italy.
| | - Alberto Burlina
- Department of Woman's and Child's Health, University Hospital of Padua, Italy.
| | - Stefano Sartori
- Department of Woman's and Child's Health, University Hospital of Padua, Italy.
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24
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de Rooy RLP, Halbertsma FJ, Struijs EA, van Spronsen FJ, Lunsing RJ, Schippers HM, van Hasselt PM, Plecko B, Wohlrab G, Whalen S, Benoist JF, Valence S, Mills PB, Bok LA. Pyridoxine dependent epilepsy: Is late onset a predictor for favorable outcome? Eur J Paediatr Neurol 2018; 22:662-666. [PMID: 29661537 DOI: 10.1016/j.ejpn.2018.03.009] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 03/21/2017] [Revised: 03/06/2018] [Accepted: 03/25/2018] [Indexed: 10/17/2022]
Abstract
AIM In pyridoxine dependent epilepsy (PDE), patients usually present with neonatal seizures. A small subgroup is characterized by late-onset beyond 2 months of age. We aim to analyze the observation of relatively good cognitive outcome in this subgroup of late-onset PDE patients. METHODS We retrospectively analyzed data from four metabolically and genetically confirmed late-onset patients with PDE due to antiquitin (ALDH7A1) deficiency. Data were analyzed regarding ALDH7A1 mutations, alpha-Aminoadipic semialdehyde (α-AASA) and pipecolic acid (PA) levels, medication during pregnancy, delivery, treatment delay, amount of seizures, pyridoxine dose, adjuvant therapy and findings on brain MRI. RESULTS Results showed that three patients had relatively good outcome (IQ 80-97), while one patient did not undergo formal testing and was considered mildly delayed. We were unable to find a clear association between the above-mentioned variables and cognitive outcome, although a less severe genotype may be present in three patients, and maternal medication could be accountable for better outcome in two patients. INTERPRETATION We suggest that favorable outcome in late onset PDE might be explained by a combination of factors. A yet unknown protective factor, different genetic variations, functional variation and secondarily variation in treatment regimens and absence of neonatal seizure induced brain damage.
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Affiliation(s)
- R L P de Rooy
- Department of Pediatrics, Zuyderland Hospital, Heerlen, The Netherlands
| | - F J Halbertsma
- Department of Pediatrics, Màxima Medical Center, Veldhoven, The Netherlands
| | - E A Struijs
- Metabolic Unit, Department of Clinical Chemistry, VU University Medical Center, Amsterdam, The Netherlands
| | - F J van Spronsen
- Department of Metabolic Diseases, Beatrix Children's Hospital, University Medical Center Groningen, University of Groningen, Groningen, The Netherlands
| | - R J Lunsing
- Department of Child Neurology, University Medical Center Groningen, University of Groningen, Groningen, The Netherlands
| | - H M Schippers
- Department of Neurology, Sint Antonius Ziekenhuis, Nieuwegein, Utrecht, The Netherlands
| | - P M van Hasselt
- Department of Pediatric Metabolic Diseases, Wilhelmina Children's Hospital, University Medical Center (UMC) Utrecht, Utrecht, The Netherlands
| | - B Plecko
- Division of Neurology, Children's Hospital, University of Zurich, Zurich, Switzerland
| | - G Wohlrab
- Division of Neurology, Children's Hospital, University of Zurich, Zurich, Switzerland
| | - S Whalen
- UF de génétique clinique, APHP, Hôpital Armand Trousseau, Paris, France
| | - J F Benoist
- Centre de Référence des Maladies Héréditaires du Métabolisme, Service de Biochimie-Hormonologie, Hôpital Robert Debré, Paris, France
| | - S Valence
- Department of Child Neurology, APHP, Armand Trousseau Hospital, Paris, France
| | - P B Mills
- Clinical and Molecular Genetics Unit, UCL Institute of Child Health, London, United Kingdom
| | - L A Bok
- Department of Pediatrics, Màxima Medical Center, Veldhoven, The Netherlands.
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Abstract
West syndrome (WS) is an early life epileptic encephalopathy associated with infantile spasms, interictal electroencephalography (EEG) abnormalities including high amplitude, disorganized background with multifocal epileptic spikes (hypsarrhythmia), and often neurodevelopmental impairments. Approximately 64% of the patients have structural, metabolic, genetic, or infectious etiologies and, in the rest, the etiology is unknown. Here we review the contribution of etiologies due to various metabolic disorders in the pathology of WS. These may include metabolic errors in organic molecules involved in amino acid and glucose metabolism, fatty acid oxidation, metal metabolism, pyridoxine deficiency or dependency, or acidurias in organelles such as mitochondria and lysosomes. We discuss the biochemical, clinical, and EEG features of these disorders as well as the evidence of how they may be implicated in the pathogenesis and treatment of WS. The early recognition of these etiologies in some cases may permit early interventions that may improve the course of the disease.
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Affiliation(s)
- Seda Salar
- Laboratory of Developmental EpilepsySaul R. Korey Department of NeurologyMontefiore/Einstein Epilepsy CenterAlbert Einstein College of MedicineBronxNew YorkU.S.A.
| | - Solomon L. Moshé
- Laboratory of Developmental EpilepsySaul R. Korey Department of NeurologyMontefiore/Einstein Epilepsy CenterAlbert Einstein College of MedicineBronxNew YorkU.S.A.
- Dominick P. Purpura Department of NeuroscienceMontefiore/Einstein Epilepsy CenterAlbert Einstein College of MedicineBronxNew YorkU.S.A.
- Department of PediatricsMontefiore/Einstein Epilepsy CenterAlbert Einstein College of MedicineBronxNew YorkU.S.A.
| | - Aristea S. Galanopoulou
- Laboratory of Developmental EpilepsySaul R. Korey Department of NeurologyMontefiore/Einstein Epilepsy CenterAlbert Einstein College of MedicineBronxNew YorkU.S.A.
- Dominick P. Purpura Department of NeuroscienceMontefiore/Einstein Epilepsy CenterAlbert Einstein College of MedicineBronxNew YorkU.S.A.
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26
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Wang S, Sun J, Tu Y, Zhu L, Feng Z. Clinical and genetic characteristics of pyridoxine-dependent epilepsy: Case series report of three Chinese patients with phenotypic variability. Exp Ther Med 2017; 14:1989-1992. [PMID: 28962114 PMCID: PMC5609134 DOI: 10.3892/etm.2017.4735] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/08/2016] [Accepted: 04/28/2017] [Indexed: 11/26/2022] Open
Abstract
Pyridoxine-dependent epilepsy (PDE) is a rare disorder caused by aldehyde dehydrogenase 7 family member A1 (ALDH7A1) deficiency. The present study reported on three Chinese cases of PDE with phenotypic variability for providing further insight into this disease. All three patients presented with recurrent seizures and readily responded to treatment with pyridoxine, in line with the typical symptomology of PDE. The three cases varied in their clinical manifestations with regard to the time of onset, seizure type, EEG findings and mental development. Four ALDH7A1 mutations were identified in Case 1 (c.1008+1G>A and c.871+5G>A) and Case 2 (c.977A>G and c.1463A>G). To the best of our knowledge, the present study was the first to report on the mutations c.871+5G>A and c.1463A>G. Early definitive diagnosis and timely treatment with pyridoxine was the cornerstone of management of PDE. Timely treatment was associated with excellent prognosis. A high index of suspicion in cases and early genetic testing may facilitate early diagnosis of this rare disease.
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Affiliation(s)
- Sanmei Wang
- National Engineering Laboratory for Birth Defects Prevention and Control of Key Technology, Beijing Key Laboratory of Pediatric Organ Failure, Affiliated Bayi Children's Hospital, General Military Hospital of Beijing PLA, Beijing 100700, P.R. China
| | - Jing Sun
- National Engineering Laboratory for Birth Defects Prevention and Control of Key Technology, Beijing Key Laboratory of Pediatric Organ Failure, Affiliated Bayi Children's Hospital, General Military Hospital of Beijing PLA, Beijing 100700, P.R. China
| | - Yao Tu
- National Engineering Laboratory for Birth Defects Prevention and Control of Key Technology, Beijing Key Laboratory of Pediatric Organ Failure, Affiliated Bayi Children's Hospital, General Military Hospital of Beijing PLA, Beijing 100700, P.R. China
| | - Lina Zhu
- National Engineering Laboratory for Birth Defects Prevention and Control of Key Technology, Beijing Key Laboratory of Pediatric Organ Failure, Affiliated Bayi Children's Hospital, General Military Hospital of Beijing PLA, Beijing 100700, P.R. China
| | - Zhichun Feng
- National Engineering Laboratory for Birth Defects Prevention and Control of Key Technology, Beijing Key Laboratory of Pediatric Organ Failure, Affiliated Bayi Children's Hospital, General Military Hospital of Beijing PLA, Beijing 100700, P.R. China
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27
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Coci EG, Codutti L, Fink C, Bartsch S, Grüning G, Lücke T, Kurth I, Riedel J. Novel homozygous missense mutation in ALDH7A1 causes neonatal pyridoxine dependent epilepsy. Mol Cell Probes 2017; 32:18-23. [DOI: 10.1016/j.mcp.2016.11.002] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/24/2016] [Revised: 11/11/2016] [Accepted: 11/11/2016] [Indexed: 01/01/2023]
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28
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Korasick DA, Tanner JJ, Henzl MT. Impact of disease-Linked mutations targeting the oligomerization interfaces of aldehyde dehydrogenase 7A1. Chem Biol Interact 2017; 276:31-39. [PMID: 28087462 DOI: 10.1016/j.cbi.2017.01.002] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/19/2016] [Revised: 12/05/2016] [Accepted: 01/09/2017] [Indexed: 11/24/2022]
Abstract
Aldehyde dehydrogenase 7A1 (ALDH7A1) is involved in lysine catabolism, catalyzing the oxidation of α-aminoadipate semialdehyde to α-aminoadipate. Certain mutations in the ALDH7A1 gene, which are presumed to reduce catalytic activity, cause an autosomal recessive seizure disorder known as pyridoxine-dependent epilepsy (PDE). Although the genetic association between ALDH7A1 and PDE is well established, little is known about the impact of PDE-mutations on the structure and catalytic function of the enzyme. Herein we report the first study of the molecular consequences of PDE mutations using purified ALDH7A1 variants. Eight variants, with mutations in the oligomer interfaces, were expressed in Escherichia coli: P78L, G83E, A129P, G137V, G138V, A149E, G255D, and G263E. All but P78L and G83E were soluble and could be purified. All six soluble mutants were catalytically inactive. The impact of the mutations on oligomerization was assessed by analytical ultracentrifugation. Wild-type ALDH7A1 is shown to exist in a dimer-tetramer equilibrium with a dissociation constant of 16 μM. In contrast to the wild-type enzyme, the variants reside in monomer-dimer equilibria and are apparently incapable of forming a tetrameric species, even at high enzyme concentration. The available evidence suggests that they are misfolded assemblies lacking the three-dimensional structure required for catalysis.
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Affiliation(s)
- David A Korasick
- Department of Biochemistry, University of Missouri-Columbia, Columbia, MO 65211, USA
| | - John J Tanner
- Department of Biochemistry, University of Missouri-Columbia, Columbia, MO 65211, USA; Department of Chemistry, University of Missouri-Columbia, Columbia, MO 65211, USA.
| | - Michael T Henzl
- Department of Biochemistry, University of Missouri-Columbia, Columbia, MO 65211, USA.
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29
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Pena IA, MacKenzie A, Van Karnebeek CDM. Current knowledge for pyridoxine-dependent epilepsy: a 2016 update. Expert Rev Endocrinol Metab 2017; 12:5-20. [PMID: 30058881 DOI: 10.1080/17446651.2017.1273107] [Citation(s) in RCA: 15] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 01/05/2023]
Abstract
Pyridoxine-dependent epilepsy (PDE) is a rare genetic condition characterized by intractable and recurrent neonatal seizures that are uniquely alleviated by high doses of pyridoxine (vitamin B6). This recessive disease is caused by mutations in ALDH7A1, a gene encoding Antiquitin, an enzyme central to lysine degradation. This results in the pathogenic accumulation of the lysine intermediates Aminoadipate Semialdehyde (AASA) and its cyclic equilibrium form Piperideine-6-carboxylate (P6C) in body fluids; P6C reacts with pyridoxal-5'-phosphate (PLP, the active form of vitamin B6) causing its inactivation and leading to pyridoxine-dependent seizures. While PDE is responsive to pharmacological dosages of pyridoxine, despite lifelong supplementation, neurodevelopment delays are observed in >75% of PDE cases. Thus, adjunct treatment strategies are emerging to both improve seizure control and moderate the delays in cognition. These adjunctive therapies, lysine restriction and arginine supplementation, separately or in combination (with pyridoxine thus termed 'triple therapy'), have shown promising results and are recommended in all PDE patients. Other new therapeutic strategies currently in preclinical phase of study include antisense therapy and substrate reduction therapy. We present here a comprehensive review of current treatment options as well as PDE phenotype, differential diagnosis, current management and views upon the future of PDE research.
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Affiliation(s)
- Izabella Agostinho Pena
- a Children's Hospital of Eastern Ontario (CHEO) Research Institute , Ottawa , ON , Canada
- b Department of Cellular and Molecular Medicine , University of Ottawa , Ottawa , ON , Canada
| | - Alex MacKenzie
- a Children's Hospital of Eastern Ontario (CHEO) Research Institute , Ottawa , ON , Canada
- b Department of Cellular and Molecular Medicine , University of Ottawa , Ottawa , ON , Canada
| | - Clara D M Van Karnebeek
- c Department of Pediatrics, BC Children's Hospital Research Institute, Centre for Molecular Medicine and Therapeutics , University of British Columbia , Vancouver BC , Canada
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30
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Abstract
Inborn errors of metabolism (IEM) are rare conditions that represent more than 1000 diseases, with a global prevalence of approximately 1:2000 individuals. Approximately, 40%-60% of IEM may present with epilepsy as one of the main neurologic signs. Epilepsy in IEM may appear at any age (fetal, newborn, infant, adolescent, or even adult). Different pathophysiological mechanisms may be responsible for the clinical phenotype, such as disturbances in energy metabolism (mitochondrial and fatty oxidation disorders, GLUT-1, and cerebral creatine deficiency), accumulation of complex molecules (lysosomal storage disorders), toxic mechanisms (organic acidurias and urea cycle disorders), or impairment of neurotransmission. Early diagnosis and, in some cases, an effective treatment may result in an excellent evolution of the IEM, in particularly seizure control. This review attempts to delineate a summary of IEM that may present with seizures or epilepsy and emphasizes the management in treatable conditions.
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Affiliation(s)
- Jaume Campistol
- From the *Neurology Department, Hospital Sant Joan de Déu, Barcelona University, Barcelona, Spain; Center for Biomedical Research on Rare Diseases (CIBERER), Instituto de Salud Carlos III, Madrid, Spain; Institute of Pediatric Research, Sant Joan de Déu, Barcelona, Spain.
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31
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Yuzyuk T, Thomas A, Viau K, Liu A, De Biase I, Botto LD, Pasquali M, Longo N. Effect of dietary lysine restriction and arginine supplementation in two patients with pyridoxine-dependent epilepsy. Mol Genet Metab 2016; 118:167-172. [PMID: 27324284 DOI: 10.1016/j.ymgme.2016.04.015] [Citation(s) in RCA: 21] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 03/12/2016] [Revised: 04/27/2016] [Accepted: 04/28/2016] [Indexed: 12/27/2022]
Abstract
Pyridoxine-Dependent Epilepsy (PDE) is a recessive disorder caused by deficiency of α-aminoadipic semialdehyde dehydrogenase in the catabolic pathway of lysine. It is characterized by intractable seizures controlled by the administration of pharmacological doses of vitamin B6. Despite seizure control with pyridoxine, intellectual disability and developmental delays are still observed in some patients with PDE, likely due to the accumulation of toxic intermediates in the lysine catabolic pathway: alpha-aminoadipic semialdehyde (AASA), delta-1-piperideine-6-carboxylate (P6C), and pipecolic acid. Here we evaluate biochemical and clinical parameters in two PDE patients treated with a lysine-restricted diet and arginine supplementation (100-150mg/kg), aimed at reducing the levels of PDE biomarkers. Lysine restriction resulted in decreased accumulation of PDE biomarkers and improved development. Plasma lysine but not plasma arginine, directly correlated with plasma levels of AASA-P6C (p<0.001, r(2)=0.640) and pipecolic acid (p<0.01, r(2)=0.484). In addition, plasma threonine strongly correlated with the levels of AASA-P6C (p<0.0001, r(2)=0.732) and pipecolic acid (p<0.005, r(2)=0.527), suggesting extreme sensitivity of threonine catabolism to pyridoxine availability. Our results further support the use of dietary therapies in combination with pyridoxine for the treatment of PDE.
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Affiliation(s)
- Tatiana Yuzyuk
- Department of Pathology, University of Utah, Salt Lake City, UT, USA; ARUP Laboratories, Salt Lake City, UT, USA; ARUP Institute for Clinical and Experimental Pathology, Salt Lake City, UT, USA.
| | - Amanda Thomas
- Department of Pathology, University of Utah, Salt Lake City, UT, USA; ARUP Laboratories, Salt Lake City, UT, USA
| | - Krista Viau
- Department of Pediatrics, University of Utah, Salt Lake City, UT, USA
| | - Aiping Liu
- ARUP Institute for Clinical and Experimental Pathology, Salt Lake City, UT, USA
| | - Irene De Biase
- Department of Pathology, University of Utah, Salt Lake City, UT, USA; ARUP Laboratories, Salt Lake City, UT, USA; ARUP Institute for Clinical and Experimental Pathology, Salt Lake City, UT, USA
| | - Lorenzo D Botto
- Department of Pediatrics, University of Utah, Salt Lake City, UT, USA
| | - Marzia Pasquali
- Department of Pathology, University of Utah, Salt Lake City, UT, USA; ARUP Laboratories, Salt Lake City, UT, USA; ARUP Institute for Clinical and Experimental Pathology, Salt Lake City, UT, USA; Department of Pediatrics, University of Utah, Salt Lake City, UT, USA
| | - Nicola Longo
- Department of Pathology, University of Utah, Salt Lake City, UT, USA; ARUP Laboratories, Salt Lake City, UT, USA; ARUP Institute for Clinical and Experimental Pathology, Salt Lake City, UT, USA; Department of Pediatrics, University of Utah, Salt Lake City, UT, USA
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32
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Pyridoxine-Dependent Epilepsy: An Expanding Clinical Spectrum. Pediatr Neurol 2016; 59:6-12. [PMID: 26995068 DOI: 10.1016/j.pediatrneurol.2015.12.013] [Citation(s) in RCA: 115] [Impact Index Per Article: 14.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 08/04/2015] [Revised: 12/16/2015] [Accepted: 12/18/2015] [Indexed: 11/20/2022]
Abstract
BACKGROUND Pyridoxine-dependent epilepsy is a rare autosomal recessive epileptic encephalopathy caused by antiquitin (ALDH7A1) deficiency. In spite of adequate seizure control, 75% of patients suffer intellectual developmental disability. Antiquitin deficiency affects lysine catabolism resulting in accumulation of α-aminoadipic semialdehyde/pyrroline 6' carboxylate and pipecolic acid. Beside neonatal refractory epileptic encephalopathy, numerous neurological manifestations and metabolic/biochemical findings have been reported. METHODS AND RESULTS We present a phenotypic spectrum of antiquitin deficiency based on a literature review (2006 to 2015) of reports (n = 49) describing the clinical presentation of confirmed patients (n > 200) and a further six patient vignettes. Possible presentations include perinatal asphyxia; neonatal withdrawal syndrome; sepsis; enterocolitis; hypoglycemia; neuroimaging abnormalities (corpus callosum and cerebellar abnormalities, hemorrhage, white matter lesions); biochemical abnormalities (lactic acidosis, electrolyte disturbances, neurotransmitter abnormalities); and seizure response to pyridoxine, pyridoxal-phosphate, and folinic acid dietary interventions. DISCUSSION The phenotypic spectrum of pyridoxine-dependent epilepsy is wide, including a myriad of neurological and systemic symptoms. Its hallmark feature is refractory seizures during the first year of life. Given its amenability to treatment with lysine-lowering strategies in addition to pyridoxine supplementation for optimal seizure control and developmental outcomes, early diagnosis of pyridoxine-dependent epilepsy is essential. All infants presenting with unexplained seizures should be screened for antiquitin deficiency by determination of α-aminoadipic semialdehyde/pyrroline 6' carboxylate (in urine, plasma or cerebrospinal fluid) and ALDH7A1 molecular analysis.
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A cohort study of pyridoxine-dependent epilepsy and high prevalence of splice site IVS11+1G>A mutation in Chinese patients. Epilepsy Res 2015; 118:1-4. [PMID: 26555630 DOI: 10.1016/j.eplepsyres.2015.10.002] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/10/2015] [Revised: 09/28/2015] [Accepted: 10/16/2015] [Indexed: 11/22/2022]
Abstract
PURPOSE Pyridoxine-dependent epilepsy (PDE) is a rare autosomal recessive disorder caused by mutations of the ALDH7A1 gene. We aimed to analyze the relations between the clinical diagnosis and treatment of PDE and ALDH7A1 gene mutations in Chinese PDE patients. METHODS The clinical manifestations, diagnosis and treatment were observed in a cohort of PDE patients with early onset of seizure. Video-electroencephalogram (VEEG) and magnetic resonance imaging (MRI) were performed. The mutation of ALDH7A1 gene was analyzed. RESULTS Of eight patients, six were males and two were females. Age of seizure onset ranged from 1 to 100 days and 75% patients presented with seizures in the neonatal period. All patients showed different degrees of developmental delay. EEGs showed focal or multifocal discharges, or were normal. Molecular analysis revealed 10 ALDH7A1 mutations, including 2 splice site mutations. Five patients had mutation at IVS11+1G>A site, six patients had missense mutations, one with nonsense mutation and another patient had 9-bp genomic deletion mutation. Among them, two mutations were first time reported. CONCLUSIONS Seizure onset was in neonatal or early infantile period in our PDE patients. Early recognition and diagnosis of the disease is necessary for early intervention and improve cognitive development in the later life. In this study, on the molecular level, we also identified the splice site mutation IVS11+1G>A as a high prevalence mutation site with a frequency of 31.25% (5 of 16 alleles) in Chinese PDE patients.
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Abstract
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Aldehyde dehydrogenase 7A1 (ALDH7A1)
is part of lysine catabolism
and catalyzes the NAD+-dependent oxidation of α-aminoadipate
semialdehyde to α-aminoadipate. Herein, we describe a structural
study of human ALDH7A1 focused on substrate recognition. Five crystal
structures and small-angle X-ray scattering data are reported, including
the first crystal structure of any ALDH7 family member complexed with
α-aminoadipate. The product binds with the ε-carboxylate
in the oxyanion hole, the aliphatic chain packed into an aromatic
box, and the distal end of the product anchored by electrostatic interactions
with five conserved residues. This binding mode resembles that of
glutamate bound to the proline catabolic enzyme ALDH4A1. Analysis
of ALDH7A1 and ALDH4A1 structures suggests key interactions that underlie
substrate discrimination. Structures of apo ALDH7A1 reveal dramatic
conformational differences from the product complex. Product binding
is associated with a 16 Å movement of the C-terminus into the
active site, which stabilizes the active conformation of the aldehyde
substrate anchor loop. The fact that the C-terminus is part of the
active site was hitherto unknown. Interestingly, the C-terminus and
aldehyde anchor loop are disordered in a new tetragonal crystal form
of the apoenzyme, implying that these parts of the enzyme are highly
flexible. Our results suggest that the active site of ALDH7A1 is disassembled
when the aldehyde site is vacant, and the C-terminus is a mobile element
that forms quaternary structural interactions that aid aldehyde binding.
These results are relevant to the c.1512delG genetic deletion associated
with pyridoxine-dependent epilepsy, which alters the C-terminus of
ALDH7A1.
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Affiliation(s)
- Min Luo
- Department of Chemistry, University of Missouri-Columbia , Columbia, Missouri 65211, United States
| | - John J Tanner
- Department of Chemistry, University of Missouri-Columbia , Columbia, Missouri 65211, United States.,Department of Biochemistry, University of Missouri-Columbia , Columbia, Missouri 65211, United States
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Tincheva S, Todorov T, Todorova A, Georgieva R, Stamatov D, Yordanova I, Kadiyska T, Georgieva B, Bojidarova M, Tacheva G, Litvinenko I, Mitev V. First cases of pyridoxine-dependent epilepsy in Bulgaria: novel mutation in the ALDH7A1 gene. Neurol Sci 2015; 36:2209-12. [DOI: 10.1007/s10072-015-2338-3] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/04/2015] [Accepted: 07/10/2015] [Indexed: 11/29/2022]
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Mefford HC, Zemel M, Geraghty E, Cook J, Clayton PT, Paul K, Plecko B, Mills PB, Nordli DR, Gospe SM. Intragenic deletions of ALDH7A1 in pyridoxine-dependent epilepsy caused by Alu-Alu recombination. Neurology 2015. [PMID: 26224730 DOI: 10.1212/wnl.0000000000001883] [Citation(s) in RCA: 23] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/15/2022] Open
Abstract
OBJECTIVE To investigate the role of intragenic deletions of ALDH7A1 in patients with clinical and biochemical evidence of pyridoxine-dependent epilepsy but only a single identifiable mutation in ALDH7A1. METHODS We designed a custom oligonucleotide array with high-density probe coverage across the ALDH7A1 gene. We performed array comparative genomic hybridization in 6 patients with clinical and biochemical evidence of pyridoxine-dependent epilepsy but only a single detectable mutation in ALDH7A1 by sequence analysis. RESULTS We found partial deletions of ALDH7A1 in 5 of 6 patients. Breakpoint analysis reveals that the deletions are likely a result of Alu-Alu recombination in all cases. The density of Alu elements within introns of ALDH7A1 suggests susceptibility to recurrent rearrangement. CONCLUSION Patients with clinical pyridoxine-dependent epilepsy and a single identifiable mutation in ALDH7A1 warrant further investigation for copy number changes involving the ALHD7A1 gene.
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Affiliation(s)
- Heather C Mefford
- From the Department of Pediatrics, Division of Genetic Medicine (H.C.M., M.Z., E.G., J.C.), and the Departments of Neurology and Pediatrics, Division of Pediatric Neurology (S.M.G.), University of Washington, Seattle; the Division of Genetic Medicine (H.C.M.), Seattle Children's Hospital, WA; the Centre for Translational Omics, Genetics, and Genomic Medicine (P.T.C., P.B.M.), UCL Institute of Child Health, London, UK; the Department of Pediatrics (K.P., B.P.), Division of Child Neurology, University Hospital Graz, Austria; the Division of Child Neurology (B.P.), University Children's Hospital Zurich, University of Zurich, Switzerland; the Departments of Pediatrics and Neurology (D.R.N.), Northwestern University Feinberg School of Medicine, Evanston, IL; the Departments of Pediatrics and Neurology (D.R.N.), Ann & Robert H. Lurie Children's Hospital of Chicago, IL; and the Departments of Neurology and Pediatrics, Division of Pediatric Neurology (S.M.G.), Seattle Children's Hospital, WA.
| | - Matthew Zemel
- From the Department of Pediatrics, Division of Genetic Medicine (H.C.M., M.Z., E.G., J.C.), and the Departments of Neurology and Pediatrics, Division of Pediatric Neurology (S.M.G.), University of Washington, Seattle; the Division of Genetic Medicine (H.C.M.), Seattle Children's Hospital, WA; the Centre for Translational Omics, Genetics, and Genomic Medicine (P.T.C., P.B.M.), UCL Institute of Child Health, London, UK; the Department of Pediatrics (K.P., B.P.), Division of Child Neurology, University Hospital Graz, Austria; the Division of Child Neurology (B.P.), University Children's Hospital Zurich, University of Zurich, Switzerland; the Departments of Pediatrics and Neurology (D.R.N.), Northwestern University Feinberg School of Medicine, Evanston, IL; the Departments of Pediatrics and Neurology (D.R.N.), Ann & Robert H. Lurie Children's Hospital of Chicago, IL; and the Departments of Neurology and Pediatrics, Division of Pediatric Neurology (S.M.G.), Seattle Children's Hospital, WA
| | - Eileen Geraghty
- From the Department of Pediatrics, Division of Genetic Medicine (H.C.M., M.Z., E.G., J.C.), and the Departments of Neurology and Pediatrics, Division of Pediatric Neurology (S.M.G.), University of Washington, Seattle; the Division of Genetic Medicine (H.C.M.), Seattle Children's Hospital, WA; the Centre for Translational Omics, Genetics, and Genomic Medicine (P.T.C., P.B.M.), UCL Institute of Child Health, London, UK; the Department of Pediatrics (K.P., B.P.), Division of Child Neurology, University Hospital Graz, Austria; the Division of Child Neurology (B.P.), University Children's Hospital Zurich, University of Zurich, Switzerland; the Departments of Pediatrics and Neurology (D.R.N.), Northwestern University Feinberg School of Medicine, Evanston, IL; the Departments of Pediatrics and Neurology (D.R.N.), Ann & Robert H. Lurie Children's Hospital of Chicago, IL; and the Departments of Neurology and Pediatrics, Division of Pediatric Neurology (S.M.G.), Seattle Children's Hospital, WA
| | - Joseph Cook
- From the Department of Pediatrics, Division of Genetic Medicine (H.C.M., M.Z., E.G., J.C.), and the Departments of Neurology and Pediatrics, Division of Pediatric Neurology (S.M.G.), University of Washington, Seattle; the Division of Genetic Medicine (H.C.M.), Seattle Children's Hospital, WA; the Centre for Translational Omics, Genetics, and Genomic Medicine (P.T.C., P.B.M.), UCL Institute of Child Health, London, UK; the Department of Pediatrics (K.P., B.P.), Division of Child Neurology, University Hospital Graz, Austria; the Division of Child Neurology (B.P.), University Children's Hospital Zurich, University of Zurich, Switzerland; the Departments of Pediatrics and Neurology (D.R.N.), Northwestern University Feinberg School of Medicine, Evanston, IL; the Departments of Pediatrics and Neurology (D.R.N.), Ann & Robert H. Lurie Children's Hospital of Chicago, IL; and the Departments of Neurology and Pediatrics, Division of Pediatric Neurology (S.M.G.), Seattle Children's Hospital, WA
| | - Peter T Clayton
- From the Department of Pediatrics, Division of Genetic Medicine (H.C.M., M.Z., E.G., J.C.), and the Departments of Neurology and Pediatrics, Division of Pediatric Neurology (S.M.G.), University of Washington, Seattle; the Division of Genetic Medicine (H.C.M.), Seattle Children's Hospital, WA; the Centre for Translational Omics, Genetics, and Genomic Medicine (P.T.C., P.B.M.), UCL Institute of Child Health, London, UK; the Department of Pediatrics (K.P., B.P.), Division of Child Neurology, University Hospital Graz, Austria; the Division of Child Neurology (B.P.), University Children's Hospital Zurich, University of Zurich, Switzerland; the Departments of Pediatrics and Neurology (D.R.N.), Northwestern University Feinberg School of Medicine, Evanston, IL; the Departments of Pediatrics and Neurology (D.R.N.), Ann & Robert H. Lurie Children's Hospital of Chicago, IL; and the Departments of Neurology and Pediatrics, Division of Pediatric Neurology (S.M.G.), Seattle Children's Hospital, WA
| | - Karl Paul
- From the Department of Pediatrics, Division of Genetic Medicine (H.C.M., M.Z., E.G., J.C.), and the Departments of Neurology and Pediatrics, Division of Pediatric Neurology (S.M.G.), University of Washington, Seattle; the Division of Genetic Medicine (H.C.M.), Seattle Children's Hospital, WA; the Centre for Translational Omics, Genetics, and Genomic Medicine (P.T.C., P.B.M.), UCL Institute of Child Health, London, UK; the Department of Pediatrics (K.P., B.P.), Division of Child Neurology, University Hospital Graz, Austria; the Division of Child Neurology (B.P.), University Children's Hospital Zurich, University of Zurich, Switzerland; the Departments of Pediatrics and Neurology (D.R.N.), Northwestern University Feinberg School of Medicine, Evanston, IL; the Departments of Pediatrics and Neurology (D.R.N.), Ann & Robert H. Lurie Children's Hospital of Chicago, IL; and the Departments of Neurology and Pediatrics, Division of Pediatric Neurology (S.M.G.), Seattle Children's Hospital, WA
| | - Barbara Plecko
- From the Department of Pediatrics, Division of Genetic Medicine (H.C.M., M.Z., E.G., J.C.), and the Departments of Neurology and Pediatrics, Division of Pediatric Neurology (S.M.G.), University of Washington, Seattle; the Division of Genetic Medicine (H.C.M.), Seattle Children's Hospital, WA; the Centre for Translational Omics, Genetics, and Genomic Medicine (P.T.C., P.B.M.), UCL Institute of Child Health, London, UK; the Department of Pediatrics (K.P., B.P.), Division of Child Neurology, University Hospital Graz, Austria; the Division of Child Neurology (B.P.), University Children's Hospital Zurich, University of Zurich, Switzerland; the Departments of Pediatrics and Neurology (D.R.N.), Northwestern University Feinberg School of Medicine, Evanston, IL; the Departments of Pediatrics and Neurology (D.R.N.), Ann & Robert H. Lurie Children's Hospital of Chicago, IL; and the Departments of Neurology and Pediatrics, Division of Pediatric Neurology (S.M.G.), Seattle Children's Hospital, WA
| | - Philippa B Mills
- From the Department of Pediatrics, Division of Genetic Medicine (H.C.M., M.Z., E.G., J.C.), and the Departments of Neurology and Pediatrics, Division of Pediatric Neurology (S.M.G.), University of Washington, Seattle; the Division of Genetic Medicine (H.C.M.), Seattle Children's Hospital, WA; the Centre for Translational Omics, Genetics, and Genomic Medicine (P.T.C., P.B.M.), UCL Institute of Child Health, London, UK; the Department of Pediatrics (K.P., B.P.), Division of Child Neurology, University Hospital Graz, Austria; the Division of Child Neurology (B.P.), University Children's Hospital Zurich, University of Zurich, Switzerland; the Departments of Pediatrics and Neurology (D.R.N.), Northwestern University Feinberg School of Medicine, Evanston, IL; the Departments of Pediatrics and Neurology (D.R.N.), Ann & Robert H. Lurie Children's Hospital of Chicago, IL; and the Departments of Neurology and Pediatrics, Division of Pediatric Neurology (S.M.G.), Seattle Children's Hospital, WA
| | - Douglas R Nordli
- From the Department of Pediatrics, Division of Genetic Medicine (H.C.M., M.Z., E.G., J.C.), and the Departments of Neurology and Pediatrics, Division of Pediatric Neurology (S.M.G.), University of Washington, Seattle; the Division of Genetic Medicine (H.C.M.), Seattle Children's Hospital, WA; the Centre for Translational Omics, Genetics, and Genomic Medicine (P.T.C., P.B.M.), UCL Institute of Child Health, London, UK; the Department of Pediatrics (K.P., B.P.), Division of Child Neurology, University Hospital Graz, Austria; the Division of Child Neurology (B.P.), University Children's Hospital Zurich, University of Zurich, Switzerland; the Departments of Pediatrics and Neurology (D.R.N.), Northwestern University Feinberg School of Medicine, Evanston, IL; the Departments of Pediatrics and Neurology (D.R.N.), Ann & Robert H. Lurie Children's Hospital of Chicago, IL; and the Departments of Neurology and Pediatrics, Division of Pediatric Neurology (S.M.G.), Seattle Children's Hospital, WA
| | - Sidney M Gospe
- From the Department of Pediatrics, Division of Genetic Medicine (H.C.M., M.Z., E.G., J.C.), and the Departments of Neurology and Pediatrics, Division of Pediatric Neurology (S.M.G.), University of Washington, Seattle; the Division of Genetic Medicine (H.C.M.), Seattle Children's Hospital, WA; the Centre for Translational Omics, Genetics, and Genomic Medicine (P.T.C., P.B.M.), UCL Institute of Child Health, London, UK; the Department of Pediatrics (K.P., B.P.), Division of Child Neurology, University Hospital Graz, Austria; the Division of Child Neurology (B.P.), University Children's Hospital Zurich, University of Zurich, Switzerland; the Departments of Pediatrics and Neurology (D.R.N.), Northwestern University Feinberg School of Medicine, Evanston, IL; the Departments of Pediatrics and Neurology (D.R.N.), Ann & Robert H. Lurie Children's Hospital of Chicago, IL; and the Departments of Neurology and Pediatrics, Division of Pediatric Neurology (S.M.G.), Seattle Children's Hospital, WA.
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Cirillo M, Venkatesan C, Millichap JJ, Stack CV, Nordli DR. Case Report: Intravenous and Oral Pyridoxine Trial for Diagnosis of Pyridoxine-Dependent Epilepsy. Pediatrics 2015; 136:e257-61. [PMID: 26101365 DOI: 10.1542/peds.2014-2423] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/24/2022] Open
Abstract
Pyridoxine-dependent epilepsy is a rare, autosomal recessive, treatable cause of neonatal seizures. Genetic testing can confirm mutations in the ALDH7A1 gene, which encodes antiquitin. To avoid delays in initiating treatment while awaiting confirmatory genetic testing, it is recommended that all neonates with unexplained seizures should receive trial of intravenous (IV) pyridoxine to assess for responsiveness. However, oral pyridoxine is not commonly continued in the absence of the typical EEG changes. Two cases are presented that highlight the potential inadequacy of this single-step approach. One neonate ultimately diagnosed with pyridoxine-dependent seizures had no EEG changes after administration of IV pyridoxine. In contrast, another neonate who did not have this diagnosis had profound EEG changes after pyridoxine administration. We present 2 cases that highlight the difficulties in using initial EEG response to IV pyridoxine in establishing a diagnosis of pyridoxine-dependent seizures in the neonate. Given the availability of biochemical markers and gene testing, we suggest that oral pyridoxine treatment should be continued until biochemical and/or genetic testing has confirmed the presence or absence of pyridoxine-dependent epilepsy.
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Affiliation(s)
- Melissa Cirillo
- Division of Neurology, and Department of Pediatrics, Northwestern University Feinberg School of Medicine, Chicago, Illinois
| | - Charu Venkatesan
- Division of Neurology, and Department of Pediatrics, Northwestern University Feinberg School of Medicine, Chicago, Illinois
| | - John J Millichap
- Department of Pediatrics, Northwestern University Feinberg School of Medicine, Chicago, Illinois Epilepsy Center, Ann and Robert H. Lurie Children's Hospital of Chicago, Chicago, Illinois; and
| | - Cynthia V Stack
- Division of Neurology, and Department of Pediatrics, Northwestern University Feinberg School of Medicine, Chicago, Illinois
| | - Douglas R Nordli
- Department of Pediatrics, Northwestern University Feinberg School of Medicine, Chicago, Illinois Epilepsy Center, Ann and Robert H. Lurie Children's Hospital of Chicago, Chicago, Illinois; and
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Abstract
Inborn errors of metabolism (IEM) are individually rare but collectively common. Approximately 25% of IEMs can have manifestations in the neonatal period. Neonates with IEM are usually healthy at birth; however, in hours to days after birth they can develop nonspecific signs that are common to several other neonatal conditions. Therefore, maintaining a high index of suspicion is extremely important for early diagnosis and the institution of appropriate therapy, which are mandatory to prevent death and ameliorate complications from many IEMs.
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Affiliation(s)
- Ayman W El-Hattab
- Division of Clinical Genetics and Metabolic Disorders, Pediatric Department, Tawam Hospital, P.O. Box 15258, Al-Ain, United Arab Emirates.
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Nasr E, Mamak E, Feigenbaum A, Donner EJ, Mercimek-Mahmutoglu S. Long-term treatment outcome of two patients with pyridoxine-dependent epilepsy caused by ALDH7A1 mutations: normal neurocognitive outcome. J Child Neurol 2015; 30:648-53. [PMID: 24789515 DOI: 10.1177/0883073814531331] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/17/2022]
Abstract
Pyridoxine-dependent epilepsy is an autosomal recessively inherited disorder of lysine catabolism caused by mutations in the ALDH7A1 gene. We report 2 patients with normal neurocognitive outcome (full-scale IQ of 108 and 74) and their more than 10 years' treatment outcome on pyridoxine monotherapy. Both patients had specific borderline impairments in visual processing speed. More long-term treatment outcome reports will increase our knowledge about the natural history of the disease.
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Affiliation(s)
- Enas Nasr
- Division of Clinical and Metabolic Genetics, Department of Pediatrics, University of Toronto, The Hospital for Sick Children, Toronto, Canada
| | - Eva Mamak
- Department of Psychology, The Hospital for Sick Children, Toronto, Canada
| | - Anette Feigenbaum
- Division of Clinical and Metabolic Genetics, Department of Pediatrics, University of Toronto, The Hospital for Sick Children, Toronto, Canada Department of Pediatrics & Biochemical Genetics, Rady Children's Hospital-San Diego, University of California, San Diego, CA, USA
| | - Elizabeth J Donner
- Division of Neurology, Department of Pediatrics, University of Toronto, The Hospital for Sick Children, Toronto, Canada
| | - Saadet Mercimek-Mahmutoglu
- Division of Clinical and Metabolic Genetics, Department of Pediatrics, University of Toronto, The Hospital for Sick Children, Toronto, Canada Genetics and Genome Biology, Research Institute, The Hospital for Sick Children, Toronto, Canada
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van Karnebeek CDM, Jaggumantri S. Current treatment and management of pyridoxine-dependent epilepsy. Curr Treat Options Neurol 2015; 17:335. [PMID: 25639976 DOI: 10.1007/s11940-014-0335-0] [Citation(s) in RCA: 20] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/06/2023]
Abstract
OPINION STATEMENT Pyridoxine-dependent epilepsy (PDE) is a rare autosomal recessive disorder and is considered as a prototypical form of metabolic epilepsy. Characterized by recurrent seizures in the prenatal, neonatal, and/or postnatal periods that are resistant to conventional anti-epileptic drugs, PDE is responsive to pharmacological dosages of pyridoxine. Presently, however, there are no clear dose recommendations for long-term treatment. While pyridoxine supplementation is the first line of treatment and should be initiated in all confirmed PDE patients at an early age, various other treatment strategies are emerging. These include a lysine-restricted diet and arginine fortification. These will be discussed in light of current evidence, together with recommendations for best management of patients with this rare but treatable metabolic epilepsy, and future research and collaborative efforts, including the International PDE Consortium.
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Affiliation(s)
- Clara D M van Karnebeek
- Division of Biochemical Diseases, Department of Pediatrics, BC Children's Hospital, Rm K3-201, 4480 Oak Street, Vancouver, BC, V6H 3V4, Canada,
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Abstract
Medications are often first-line treatment for epilepsy in children. A detailed review of antiepileptic drugs and their application in various epilepsy syndromes is provided in the article "Antiepileptic Drugs--A Review" by Sankaraneni and Lachhwani (this issue). Here, we will focus on nonmedicinal approaches-some fairly longstanding and described since Biblical times such as the ketogenic diet while others are relatively new such as neurostimulation. Yet, others such as cannabinoids have been utilized for centuries for their medicinal properties, but we are just learning the scientific basis behind their efficacy. Families are often interested in nonmedicinal avenues of treatment, and knowledge of these options can empower a pediatrician to help families make choices that have scientific validity.
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Abstract
Background:Pyridoxine dependent epilepsy (PDE) is characterized by neonatal epileptic encepahalopathy responsive to pharmacological doses of vitamin B6. Recently an autosomal recessive deficiency in Antiquitin (ALDH7A1), a gene involved in the catabolism of lysine has been identified as the underlying cause.Case report:In 21 and 23 year-old sisters, who had presented with neonatal / early infantile onset seizures, PDE was confirmed by elevated urinary alpha aminoadipic- 6- semialdehyde (α-AASA) excretion and compound heterozygosity for two known ALDH7A1 missense mutations. Although epilepsy was well controlled upon treatment with pyridoxine, thiamine, phenytoin and carbamazepine since early infancy, both had developmental delay with prominent speech delay as children. As adults, despite the same genetic background and early treatment with pyridoxine, their degree of intellectual disability (ID) differed widely. While the older sister's cognitive functions were in the moderate ID range and she was not able to live unattended, the younger sister had only mild ID and was able to live independently.Conclusion:Although seizures are a defining feature of PDE, other disease manifestations can vary widely even within the same family. Adult neurologists should be aware that the diagnosis of PDE can be delayed and PDE should be considered in the differential diagnosis of adults with seizure disorders dating from childhood.
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Abstract
Neonatal seizures are the most important indicators of underlying brain injury. Seizures in a neonate are different from seizures in older children in many aspects including clinical presentation and etiology. The neonatal brain is immature and tends to have a decreased seizure threshold. Neonatal seizures are classified, based on their presentation as, clinical seizures, electroclinical seizures and electroencephalographic seizures; based on the pathophysiology as epileptic and nonepileptic seizures; and also on the basis of the etiology. Hypoxic ischemic encephalopathy is the leading cause of neonatal seizures, followed by intracranial hemorrhage, metabolic causes such as hypoglycemia and hypocalcemia, intracranial infections and strokes. Neonatal epilepsy syndromes are rare. Electroencephalography (EEG) is the gold standard for diagnosis. Amplitude integrated EEG (aEEG) is also used for continuous monitoring. The approach to management consists of initial stabilization of the neonate followed by treatment of potentially correctable injurious processes such as hypocalcemia, hypoglycemia and electrolyte disturbances, etiology specific therapies and antiepileptic drug (AED) therapy. Phenobarbital remains the first line AED therapy. Pharmacokinetic data on newer drugs is limited. Prognosis depends on the etiology, seizure type, neurological examination at discharge and EEG. Long term neurodevelopmental follow up is essential for babies with neonatal seizures.
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Affiliation(s)
- Sujata Kanhere
- Division of Pediatric Neurology, Department of Pediatrics & Neonatology, K.J. Somaiya Medical College, Hospital & Research Centre, Mumbai, Maharashtra, 400022, India,
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Abstract
Uveal coloboma is a potentially blinding congenital ocular malformation caused by failure of the optic fissure to close during development. Although mutations in numerous genes have been described, these account for a minority of cases, complicating molecular diagnosis and genetic counseling. Here we describe a key role of aldh7a1 as a gene necessary for normal eye development. We show that morpholino knockdown of aldh7a1 in zebrafish causes uveal coloboma and misregulation of nlz1, another known contributor to the coloboma phenotype, as well as skeletal abnormalities. Knockdown of aldh7a1 leads to reduced cell proliferation in the optic cup of zebrafish, delaying the approximation of the edges of the optic fissure. The aldh7a1 morphant phenotype is partially rescued by co-injection of nlz1 mRNA suggesting that nlz1 is functionally downstream of aldh7a1 in regulating cell proliferation in the optic cup. These results support a role of aldh7a1 in ocular development and skeletal abnormalities in zebrafish.
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Baumgart A, Spiczak SV, Verhoeven-Duif NM, Møller RS, Boor R, Muhle H, Jähn JA, Klitten LL, Hjalgrim H, Lindhout D, Stephani U, van Kempen MJA, Helbig I. Atypical vitamin B6 deficiency: a rare cause of unexplained neonatal and infantile epilepsies. J Child Neurol 2014; 29:704-7. [PMID: 24114605 DOI: 10.1177/0883073813505354] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/16/2022]
Abstract
ALDH7A1 and PNPO deficiencies are rare inborn errors of vitamin B6 metabolism causing perinatal seizure disorders. The phenotypic variability, however, is broad. To assess the frequency of these deficiencies in unexplained infantile epilepsy, we screened 113 patients for mutations in both genes. We identified 1 patient with an epilepsy phenotype resembling Dravet syndrome and likely pathogenic mutations in ALDH7A1. Presenting features were highly atypical of pyridoxine-dependent epilepsy, including febrile seizures, response to anticonvulsive drugs, and periods of seizure freedom without pyridoxine treatment. "Hidden" vitamin B6 deficiencies might be rare but treatable causes of unexplained epilepsy extending beyond the classical phenotypes.
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Affiliation(s)
- Anna Baumgart
- 1Department of Neuropediatrics, University Medical Center Schleswig-Holstein, Kiel, Germany
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Coulter-Mackie MB, Tiebout S, van Karnebeek C, Stockler S. Overexpression of recombinant human antiquitin in E. coli: partial enzyme activity in selected ALDH7A1 missense mutations associated with pyridoxine-dependent epilepsy. Mol Genet Metab 2014; 111:462-6. [PMID: 24613284 DOI: 10.1016/j.ymgme.2014.02.010] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 02/13/2014] [Accepted: 02/14/2014] [Indexed: 12/01/2022]
Abstract
Pyridoxine-dependent epilepsy (PDE) is an autosomal recessive disorder characterized by early onset seizures responsive to pyridoxine and caused by a defect in the α-aminoadipic semialdehyde dehydrogenase (antiquitin) gene (ALDH7A1). We selected four PDE-associated missense ALDH7A1 mutations, p.V367F, p.F410L, p.Q425R, and p.C450S, generated them in a recombinant human antiquitin cDNA with expression in E. coli at either 30°C or 37°C. One mutation, p.C450S, demonstrated substantial activity after expression at both temperatures, potentially contributing to milder biochemical and clinical phenotypes. The p.Q425R mutation yielded no activity at either temperature. The other two mutations yielded significant enzymatic activity at 30°C and markedly reduced activity at 37°C. For these latter three mutations, the markedly reduced or absent enzymatic activity resulting from expression at 37°C may be consistent with pathogenicity.
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Affiliation(s)
- Marion B Coulter-Mackie
- Department of Pediatrics, University of British Columbia, Vancouver, BC, Canada; Department of Pathology & Laboratory Medicine, University of British Columbia, Vancouver, BC, Canada.
| | - Sylvia Tiebout
- Department of Pediatrics, University of British Columbia, Vancouver, BC, Canada.
| | - Clara van Karnebeek
- Department of Pediatrics, University of British Columbia, Vancouver, BC, Canada; Centre for Molecular Medicine and Therapeutics, Vancouver, BC, Canada.
| | - Sylvia Stockler
- Department of Pediatrics, University of British Columbia, Vancouver, BC, Canada.
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Yang Z, Yang X, Wu Y, Wang J, Zhang Y, Xiong H, Jiang Y, Qin J. Clinical diagnosis, treatment, and ALDH7A1 mutations in pyridoxine-dependent epilepsy in three Chinese infants. PLoS One 2014; 9:e92803. [PMID: 24664145 PMCID: PMC3963937 DOI: 10.1371/journal.pone.0092803] [Citation(s) in RCA: 17] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/26/2013] [Accepted: 02/26/2014] [Indexed: 11/19/2022] Open
Abstract
Pyridoxine-dependent epilepsy (PDE) is a rare autosomal recessive disorder that causes seizures in neonates and infants. Mutations of the ALDH7A1 gene are now recognized as the molecular basis PDE and help to define this disease. Three Chinese children with PDE were clinically analyzed, followed by treatment and examination of the ALDH7A1 mutations. The seizures of the 3 patients were all resistant to multiple anticonvulsants (2 to 7 types). For case 1, onset of seizures was at the age of 2 months. His seizures were well controlled by intravenous pyridoxine for several days at the age of 3 months 20 days and recurred at intervals of 13, 14 and 38 days after pyridoxine withdrawn for 3 times. At the age of 7 months, symptoms of PDE appeared and uninterrupted oral pyridoxine started. For case 2, her seizures occurred at 8 days after birth. After administration of multiple antiepileptic drugs observed ineffective, high-dose pyridoxine continuous therapy was taken at the age of 10 months and the significant treatment effect induced a diagnostic PDE. Seizure onset in case 3 was at the first day of birth. He experienced inadvertently pyridoxine therapy several times (first time at 2 days after birth) and achieved good therapeutic effect, which was confirmed by physicians until 4 months 10 days. The treatment process in our 3 patients suggested that pyridoxine should be early and purposefully used in patients with early onset seizures. ALDH7A1 gene mutation analysis revealed compound heterozygous mutations in each case: heterozygous c.410G>A (p.G137E) and IVS11+1G>A in case 1, heterozygous c.952G>C (p.A318P) and heterozygous c.965C>T (p.A322V) in case 2, and heterozygous c.902A>T (p.N301I) and IVS11+1G>A in case 3. Only p.N301I was reported previously, all other mutations were novel. This is the first time to report cases of Chinese patients diagnosed with PDE by molecular genetic analysis.
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Affiliation(s)
- Zhixian Yang
- Department of Pediatrics, Peking University First Hospital, Xicheng District, Beijing, China
- * E-mail:
| | - Xiaoling Yang
- Department of Pediatrics, Peking University First Hospital, Xicheng District, Beijing, China
| | - Ye Wu
- Department of Pediatrics, Peking University First Hospital, Xicheng District, Beijing, China
| | - Jingmin Wang
- Department of Pediatrics, Peking University First Hospital, Xicheng District, Beijing, China
| | - Yuehua Zhang
- Department of Pediatrics, Peking University First Hospital, Xicheng District, Beijing, China
| | - Hui Xiong
- Department of Pediatrics, Peking University First Hospital, Xicheng District, Beijing, China
| | - Yuwu Jiang
- Department of Pediatrics, Peking University First Hospital, Xicheng District, Beijing, China
| | - Jiong Qin
- Department of Pediatrics, Peking University First Hospital, Xicheng District, Beijing, China
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Jansen LA, Hevner RF, Roden WH, Hahn SH, Jung S, Gospe SM. Glial localization of antiquitin: implications for pyridoxine-dependent epilepsy. Ann Neurol 2014; 75:22-32. [PMID: 24122892 DOI: 10.1002/ana.24027] [Citation(s) in RCA: 32] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/18/2013] [Revised: 08/26/2013] [Accepted: 09/10/2013] [Indexed: 11/10/2022]
Abstract
OBJECTIVE A high incidence of structural brain abnormalities has been reported in individuals with pyridoxine-dependent epilepsy (PDE). PDE is caused by mutations in ALDH7A1, also known as antiquitin. How antiquitin dysfunction leads to cerebral dysgenesis is unknown. In this study, we analyzed tissue from a child with PDE as well as control human and murine brain to determine the normal distribution of antiquitin, its distribution in PDE, and associated brain malformations. METHODS Formalin-fixed human brain sections were subjected to histopathology and fluorescence immunohistochemistry studies. Frozen brain tissue was utilized for measurement of PDE-associated metabolites and Western blot analysis. Comparative studies of antiquitin distribution were performed in developing mouse brain sections. RESULTS Histologic analysis of PDE cortex revealed areas of abnormal radial neuronal organization consistent with type Ia focal cortical dysplasia. Heterotopic neurons were identified in subcortical white matter, as was cortical astrogliosis, hippocampal sclerosis, and status marmoratus of the basal ganglia. Highly elevated levels of lysine metabolites were present in postmortem PDE cortex. In control human and developing mouse brain, antiquitin immunofluorescence was identified in radial glia, mature astrocytes, ependyma, and choroid plexus epithelium, but not in neurons. In PDE cortex, antiquitin immunofluorescence was greatly attenuated with evidence of perinuclear accumulation in astrocytes. INTERPRETATION Antiquitin is expressed within glial cells in the brain, and its dysfunction in PDE is associated with neuronal migration abnormalities and other structural brain defects. These malformations persist despite postnatal pyridoxine supplementation and likely contribute to neurodevelopmental impairments.
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Affiliation(s)
- Laura A Jansen
- Department of Neurology, University of Washington, Seattle, WA; Seattle Children's Research Institute, Seattle, WA
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Byeon JH, Shin E, Kim GH, Lee K, Hong YS, Lee JW, Eun BL. Application of array-based comparative genomic hybridization to pediatric neurologic diseases. Yonsei Med J 2014; 55:30-6. [PMID: 24339284 PMCID: PMC3874920 DOI: 10.3349/ymj.2014.55.1.30] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 01/13/2023] Open
Abstract
PURPOSE Array comparative genomic hybridization (array-CGH) is a technique used to analyze quantitative increase or decrease of chromosomes by competitive DNA hybridization of patients and controls. This study aimed to evaluate the benefits and yield of array-CGH in comparison with conventional karyotyping in pediatric neurology patients. MATERIALS AND METHODS We included 87 patients from the pediatric neurology clinic with at least one of the following features: developmental delay, mental retardation, dysmorphic face, or epilepsy. DNA extracted from patients and controls was hybridized on the Roche NimbleGen 135K oligonucleotide array and compared with G-band karyotyping. The results were analyzed with findings reported in recent publications and internet databases. RESULTS Chromosome imbalances, including 9 cases detected also by G-band karyotyping, were found in 28 patients (32.2%), and at least 19 of them seemed to be causally related to the abnormal phenotypes. Regarding each clinical symptom, 26.2% of 42 developmental delay patients, 44.4% of 18 mental retardation patients, 42.9% of 28 dysmorphic face patients, and 34.6% of 26 epilepsy patients showed abnormal array results. CONCLUSION Although there were relatively small number of tests in patients with pediatric neurologic disease, this study demonstrated that array-CGH is a very useful tool for clinical diagnosis of unknown genome abnormalities performed in pediatric neurology clinics.
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Affiliation(s)
- Jung Hye Byeon
- Department of Pediatrics, Korea University Guro Hospital, 148 Gurodong-ro, Guro-gu, Seoul 152-703, Korea.
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Papetti L, Parisi P, Leuzzi V, Nardecchia F, Nicita F, Ursitti F, Marra F, Paolino MC, Spalice A. Metabolic epilepsy: an update. Brain Dev 2013; 35:827-41. [PMID: 23273990 DOI: 10.1016/j.braindev.2012.11.010] [Citation(s) in RCA: 29] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 09/21/2011] [Revised: 10/23/2012] [Accepted: 11/25/2012] [Indexed: 10/27/2022]
Abstract
Inborn errors of metabolism comprise a large class of genetic diseases involving disorders of metabolism. Presentation is usually in the neonatal period or infancy but can occur at any time, even in adulthood. Seizures are frequent symptom in inborn errors of metabolism, with no specific seizure types or EEG signatures. The 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. However a specific diagnosis of metabolic disorders in epileptic patients may provide the possibility of specific treatments that can improve seizures. In a few metabolic diseases, epilepsy responds to specific treatments based on diet or supplementation of cofactors (vitamin-responsive epilepsies), but for most of them specific treatment is unfortunately not available, and conventional antiepileptic drugs must be used, often with no satisfactory success. In this review we present an overview of metabolic epilepsies based on various criteria such as treatability, age of onset, seizure type, and pathogenetic background.
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Affiliation(s)
- Laura Papetti
- Department of Pediatrics, Child Neurology Division, Sapienza University of Rome, Italy
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