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Zimmern V, Minassian B. Progressive Myoclonus Epilepsy: A Scoping Review of Diagnostic, Phenotypic and Therapeutic Advances. Genes (Basel) 2024; 15:171. [PMID: 38397161 PMCID: PMC10888128 DOI: 10.3390/genes15020171] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/02/2024] [Revised: 01/23/2024] [Accepted: 01/26/2024] [Indexed: 02/25/2024] Open
Abstract
The progressive myoclonus epilepsies (PME) are a diverse group of disorders that feature both myoclonus and seizures that worsen gradually over a variable timeframe. While each of the disorders is individually rare, they collectively make up a non-trivial portion of the complex epilepsy and myoclonus cases that are seen in tertiary care centers. The last decade has seen substantial progress in our understanding of the pathophysiology, diagnosis, prognosis, and, in select disorders, therapies of these diseases. In this scoping review, we examine English language publications from the past decade that address diagnostic, phenotypic, and therapeutic advances in all PMEs. We then highlight the major lessons that have been learned and point out avenues for future investigation that seem promising.
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Affiliation(s)
- Vincent Zimmern
- Division of Child Neurology, University of Texas Southwestern, Dallas, TX 75390, USA;
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2
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Cameron JM, Ellis CA, Berkovic SF. ILAE Genetics Literacy series: Progressive myoclonus epilepsies. Epileptic Disord 2023; 25:670-680. [PMID: 37616028 PMCID: PMC10947580 DOI: 10.1002/epd2.20152] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/24/2023] [Revised: 07/21/2023] [Accepted: 08/19/2023] [Indexed: 08/25/2023]
Abstract
Progressive Myoclonus Epilepsy (PME) is a rare epilepsy syndrome characterized by the development of progressively worsening myoclonus, ataxia, and seizures. A molecular diagnosis can now be established in approximately 80% of individuals with PME. Almost fifty genetic causes of PME have now been established, although some remain extremely rare. Herein, we provide a review of clinical phenotypes and genotypes of the more commonly encountered PMEs. Using an illustrative case example, we describe appropriate clinical investigation and therapeutic strategies to guide the management of this often relentlessly progressive and devastating epilepsy syndrome. This manuscript in the Genetic Literacy series maps to Learning Objective 1.2 of the ILAE Curriculum for Epileptology (Epileptic Disord. 2019;21:129).
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Affiliation(s)
- Jillian M. Cameron
- Epilepsy Research Centre, Department of MedicineUniversity of MelbourneAustin HealthMelbourneVictoriaAustralia
| | - Colin A. Ellis
- Department of NeurologyUniversity of Pennsylvania Perelman School of MedicinePhiladelphiaPennsylvaniaUSA
| | - Samuel F. Berkovic
- Epilepsy Research Centre, Department of MedicineUniversity of MelbourneAustin HealthMelbourneVictoriaAustralia
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Nagree MS, Rybova J, Kleynerman A, Ahrenhoerster CJ, Saville JT, Xu T, Bachochin M, McKillop WM, Lawlor MW, Pshezhetsky AV, Isaeva O, Budde MD, Fuller M, Medin JA. Spinal muscular atrophy-like phenotype in a mouse model of acid ceramidase deficiency. Commun Biol 2023; 6:560. [PMID: 37231125 DOI: 10.1038/s42003-023-04932-w] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/29/2022] [Accepted: 05/12/2023] [Indexed: 05/27/2023] Open
Abstract
Mutations in ASAH1 have been linked to two allegedly distinct disorders: Farber disease (FD) and spinal muscular atrophy with progressive myoclonic epilepsy (SMA-PME). We have previously reported FD-like phenotypes in mice harboring a single amino acid substitution in acid ceramidase (ACDase), P361R, known to be pathogenic in humans (P361R-Farber). Here we describe a mouse model with an SMA-PME-like phenotype (P361R-SMA). P361R-SMA mice live 2-3-times longer than P361R-Farber mice and have different phenotypes including progressive ataxia and bladder dysfunction, which suggests neurological dysfunction. We found profound demyelination, loss of axons, and altered sphingolipid levels in P361R-SMA spinal cords; severe pathology was restricted to the white matter. Our model can serve as a tool to study the pathological effects of ACDase deficiency on the central nervous system and to evaluate potential therapies for SMA-PME.
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Affiliation(s)
- Murtaza S Nagree
- Department of Medical Biophysics, University of Toronto, Toronto, M5G 1L7, ON, Canada
- Department of Pediatrics, Medical College of Wisconsin, Milwaukee, WI, 53226, USA
| | - Jitka Rybova
- Department of Pediatrics, Medical College of Wisconsin, Milwaukee, WI, 53226, USA
| | - Annie Kleynerman
- Department of Pediatrics, Medical College of Wisconsin, Milwaukee, WI, 53226, USA
| | | | - Jennifer T Saville
- Genetics and Molecular Pathology, SA Pathology at Women's and Children's Hospital, and Adelaide Medical School, University of Adelaide, Adelaide, SA, 5006, Australia
| | - TianMeng Xu
- CHU Sainte-Justine, Université de Montréal, Montréal, QC, H3T 1C5, Canada
| | | | - William M McKillop
- Department of Pediatrics, Medical College of Wisconsin, Milwaukee, WI, 53226, USA
| | - Michael W Lawlor
- Department of Pathology and Neuroscience Research Center, Medical College of Wisconsin, Milwaukee, WI, 53226, USA
| | | | - Olena Isaeva
- Department of Cell Biology, Neurobiology and Anatomy, Medical College of Wisconsin, Milwaukee, WI, 53226, USA
| | - Matthew D Budde
- Clement J. Zablocki Veteran's Affairs Medical Center, Milwaukee, WI, 53295, USA
- Department of Neurosurgery, Medical College of Wisconsin, Milwaukee, WI, 53226, USA
| | - Maria Fuller
- Genetics and Molecular Pathology, SA Pathology at Women's and Children's Hospital, and Adelaide Medical School, University of Adelaide, Adelaide, SA, 5006, Australia
- Adelaide Medical School, University of Adelaide, Adelaide, SA, 5005, Australia
| | - Jeffrey A Medin
- Department of Medical Biophysics, University of Toronto, Toronto, M5G 1L7, ON, Canada.
- Department of Pediatrics, Medical College of Wisconsin, Milwaukee, WI, 53226, USA.
- Department of Biochemistry, Medical College of Wisconsin, Milwaukee, WI, 53226, USA.
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Kleynerman A, Rybova J, Faber ML, McKillop WM, Levade T, Medin JA. Acid Ceramidase Deficiency: Bridging Gaps between Clinical Presentation, Mouse Models, and Future Therapeutic Interventions. Biomolecules 2023; 13:biom13020274. [PMID: 36830643 PMCID: PMC9953133 DOI: 10.3390/biom13020274] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/09/2023] [Revised: 01/25/2023] [Accepted: 01/27/2023] [Indexed: 02/04/2023] Open
Abstract
Farber disease (FD) and spinal muscular atrophy with progressive myoclonic epilepsy (SMA-PME) are ultra-rare, autosomal-recessive, acid ceramidase (ACDase) deficiency disorders caused by ASAH1 gene mutations. Currently, 73 different mutations in the ASAH1 gene have been described in humans. These mutations lead to reduced ACDase activity and ceramide (Cer) accumulation in many tissues. Presenting as divergent clinical phenotypes, the symptoms of FD vary depending on central nervous system (CNS) involvement and severity. Classic signs of FD include, but are not limited to, a hoarse voice, distended joints, and lipogranulomas found subcutaneously and in other tissues. Patients with SMA-PME lack the most prominent clinical signs seen in FD. Instead, they demonstrate muscle weakness, tremors, and myoclonic epilepsy. Several ACDase-deficient mouse models have been developed to help elucidate the complex consequences of Cer accumulation. In this review, we compare clinical reports on FD patients and experimental descriptions of ACDase-deficient mouse models. We also discuss clinical presentations, potential therapeutic strategies, and future directions for the study of FD and SMA-PME.
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Affiliation(s)
- Annie Kleynerman
- Department of Pediatrics, Medical College of Wisconsin, Milwaukee, WI 53226, USA
| | - Jitka Rybova
- Department of Pediatrics, Medical College of Wisconsin, Milwaukee, WI 53226, USA
| | - Mary L. Faber
- Department of Pediatrics, Medical College of Wisconsin, Milwaukee, WI 53226, USA
| | - William M. McKillop
- Department of Pediatrics, Medical College of Wisconsin, Milwaukee, WI 53226, USA
| | - Thierry Levade
- Laboratoire de Biochimie Métabolique, CHU Toulouse, and INSERM U1037, Centre de Recherches en Cancérologie de Toulouse, Université Paul Sabatier, 31062 Toulouse, France
| | - Jeffrey A. Medin
- Department of Pediatrics, Medical College of Wisconsin, Milwaukee, WI 53226, USA
- Department of Biochemistry, Medical College of Wisconsin, Milwaukee, WI 53226, USA
- Correspondence: ; Tel.: +1-414-955-4118
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Lee MM, McDowell GSV, De Vivo DC, Friedman D, Berkovic SF, Spanou M, Dinopoulos A, Grand K, Sanchez‐Lara PA, Allen‐Sharpley M, Warman‐Chardon J, Solyom A, Levade T, Schuchman EH, Bennett SAL, Dyment DA, Pearson TS. The clinical spectrum of SMA-PME and in vitro normalization of its cellular ceramide profile. Ann Clin Transl Neurol 2022; 9:1941-1952. [PMID: 36325744 PMCID: PMC9735369 DOI: 10.1002/acn3.51687] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/05/2022] [Revised: 10/12/2022] [Accepted: 10/14/2022] [Indexed: 11/06/2022] Open
Abstract
OBJECTIVE The objectives of this study were to define the clinical and biochemical spectrum of spinal muscular atrophy with progressive myoclonic epilepsy (SMA-PME) and to determine if aberrant cellular ceramide accumulation could be normalized by enzyme replacement. METHODS Clinical features of 6 patients with SMA-PME were assessed by retrospective chart review, and a literature review of 24 previously published cases was performed. Leukocyte enzyme activity of acid ceramidase was assessed with a fluorescence-based assay. Skin fibroblast ceramide content and was assessed by high performance liquid chromatography, electrospray ionization tandem mass spectroscopy. Enzyme replacement was assessed using recombinant human acid ceramidase (rhAC) in vitro. RESULTS The six new patients showed the hallmark features of SMA-PME, with variable initial symptom and age of onset. Five of six patients carried at least one of the recurrent SMA-PME variants observed in two specific codons of ASAH1. A review of 30 total cases revealed that patients who were homozygous for the most common c.125C > T variant presented in the first decade of life with limb-girdle weakness as the initial symptom. Sensorineural hearing loss was associated with the c.456A > C variant. Leukocyte acid ceramidase activity varied from 4.1%-13.1% of controls. Ceramide species in fibroblasts were detected and total cellular ceramide content was elevated by 2 to 9-fold compared to controls. Treatment with rhAC normalized ceramide profiles in cultured fibroblasts to control levels within 48 h. INTERPRETATION This study details the genotype-phenotype correlations observed in SMA-PME and shows the impact of rhAC to correct the abnormal cellular ceramide profile in cells.
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Affiliation(s)
- Michelle M. Lee
- Department of NeurologyWashington University School of MedicineSt. LouisMissouriUSA
| | - Graeme S. V. McDowell
- Neural Regeneration Laboratory, Ottawa Institute of Systems Biology, Department of Biochemistry, Microbiology and ImmunologyUniversity of OttawaOttawaOntarioCanada
| | - Darryl C. De Vivo
- Departments of Neurology and PediatricsColumbia University Irving Medical CenterNew YorkNew YorkUSA
| | - Daniel Friedman
- Department of NeurologyNYU Grossman School of MedicineNew YorkNew YorkUSA
| | - Samuel F. Berkovic
- Epilepsy Research Centre, Department of MedicineUniversity of MelbourneHeidelbergVictoriaAustralia
| | - Maria Spanou
- Pediatric Neurology Division, 3rd Department of PediatricsAttikon University HospitalAthensGreece
| | - Argirios Dinopoulos
- Pediatric Neurology Division, 3rd Department of PediatricsAttikon University HospitalAthensGreece
| | - Katheryn Grand
- Department of PediatricsCedars‐Sinai Medical CenterLos AngelesCaliforniaUSA
| | | | | | - Jodi Warman‐Chardon
- Department of Medicine (Neurology)Ottawa Hospital Research InstituteOttawaOntarioCanada,Children's Hospital of Eastern Ontario Research InstituteOttawaOntarioCanada
| | | | - Thierry Levade
- Laboratoire de Biochimie MétaboliqueCHU Toulouse, INSERM U1037, Centre de Recherches en Cancérologie de Toulouse, Université Paul Sabatier ToulouseToulouseFrance
| | - Edward H. Schuchman
- Department of Genetics and Genomic SciencesIcahn School of Medicine at Mount SinaiNew YorkNYUSA
| | - Steffany A. L. Bennett
- Neural Regeneration Laboratory, Ottawa Institute of Systems Biology, Department of Biochemistry, Microbiology and ImmunologyUniversity of OttawaOttawaOntarioCanada
| | - David A. Dyment
- Children's Hospital of Eastern Ontario Research InstituteOttawaOntarioCanada
| | - Toni S. Pearson
- Department of NeurologyWashington University School of MedicineSt. LouisMissouriUSA,Departments of Neurology and PediatricsColumbia University Irving Medical CenterNew YorkNew YorkUSA
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Niu Y, Gong P, Jiao X, Xu Z, Zhang Y, Yang Z. Genetic and phenotypic spectrum of Chinese patients with epilepsy and photosensitivity. Front Neurol 2022; 13:907228. [PMID: 36034301 PMCID: PMC9416002 DOI: 10.3389/fneur.2022.907228] [Citation(s) in RCA: 4] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/21/2022] [Accepted: 07/08/2022] [Indexed: 11/13/2022] Open
Abstract
Objective To determine the contribution of genetic etiologies in epilepsy with photosensitivity. Methods A total of 35 epileptic patients with genetic photosensitivity from January 2019 to May 2021 were analyzed. Results Pathogenic variants were identified in 35 patients, including SCN1A(7) CHD2(6), TPP1(3), SYNGAP1(3), GABRA1(2), GABRG2(1), KCTD7(1), MFSD8(1), KCNC1(1) GBA(1), CACNA1A(1), KCNMA1(1), FLNA(1), SZT2(1), SLC2A1(1), 5q33.2-34del(1), and mitochondrial variants(3). The predominant epileptic syndrome was progressive myoclonus epilepsy (PME) and Dravet syndrome, while the most common seizure type in both spontaneous seizures and photoconvulsive response (PCR) was myoclonic seizures. The abnormal EEG background and brain MRI were mainly seen in the PME patients. In PME, initial low-frequencies (1–6 Hz) photosensitivity was observed in 70% (7/10) of patients. Among the other patients, 12 patients (48.0%, 12/25) had photosensitivity at initial low -frequencies and 12 patients (48.0%, 12/25) had photosensitivity at initial middle frequencies (6–20 Hz). At the 1-year follow-up, 77.7% (21/27) still remained photosensitive. Conclusion The most common genes for epilepsy with genetic photosensitivity are SCN1A and CHD2, and the most common syndromes are PME and Dravet syndrome. MFSD8, KCNMA1, SZT2, FLNA, and SLC2A1 variants might be candidate genes for photosensitivity. PPRs at initial low-frequencies may be a marker of PME, and the most typical feature of genetic photosensitivity may be low- or middle- frequencies induced PPRs. Photosensitivity in epilepsy with genetic photosensitivity may be difficult to disappear in a short period of time.
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Affiliation(s)
- Yue Niu
- Department of Pediatrics, Peking University First Hospital, Beijing, China
| | - Pan Gong
- Department of Pediatrics, Peking University First Hospital, Beijing, China
| | - Xianru Jiao
- Department of Pediatrics, Peking University First Hospital, Beijing, China
| | - Zhao Xu
- 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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7
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Five patients with Spinal muscular atrophy-progressive myoclonic epilepsy (SMA-PME): a novel pathogenic variant, treatment and review of the literature. Neuromuscul Disord 2022; 32:806-810. [DOI: 10.1016/j.nmd.2022.08.002] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/15/2022] [Revised: 08/02/2022] [Accepted: 08/05/2022] [Indexed: 11/18/2022]
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Consequences of excessive glucosylsphingosine in glucocerebrosidase-deficient zebrafish. J Lipid Res 2022; 63:100199. [PMID: 35315333 PMCID: PMC9058576 DOI: 10.1016/j.jlr.2022.100199] [Citation(s) in RCA: 2] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/04/2021] [Revised: 02/26/2022] [Accepted: 03/08/2022] [Indexed: 12/01/2022] Open
Abstract
In Gaucher disease (GD), the deficiency of glucocerebrosidase causes lysosomal accumulation of glucosylceramide (GlcCer), which is partly converted by acid ceramidase to glucosylsphingosine (GlcSph) in the lysosome. Chronically elevated blood and tissue GlcSph is thought to contribute to symptoms in GD patients as well as to increased risk for Parkinson’s disease. On the other hand, formation of GlcSph may be beneficial since the water soluble sphingoid base is excreted via urine and bile. To study the role of excessive GlcSph formation during glucocerebrosidase deficiency, we studied zebrafish that have two orthologs of acid ceramidase, Asah1a and Asah1b. Only the latter is involved in the formation of GlcSph in glucocerebrosidase-deficient zebrafish as revealed by knockouts of Asah1a or Asah1b with glucocerebrosidase deficiency (either pharmacologically induced or genetic). Comparison of zebrafish with excessive GlcSph (gba1-/- fish) and without GlcSph (gba1-/-:asah1b-/- fish) allowed us to study the consequences of chronic high levels of GlcSph. Prevention of excessive GlcSph in gba1-/-:asah1b-/- fish did not restrict storage cells, GlcCer accumulation, or neuroinflammation. However, GD fish lacking excessive GlcSph show an ameliorated course of disease reflected by significantly increased lifespan, delayed locomotor abnormality, and delayed development of an abnormal curved back posture. The loss of tyrosine hydroxylase 1 (th1) mRNA, a marker of dopaminergic neurons, is slowed down in brain of GD fish lacking excessive GlcSph. In conclusion, in the zebrafish GD model, excess GlcSph has little impact on (neuro)inflammation or the presence of GlcCer-laden macrophages but rather seems harmful to th1-positive dopaminergic neurons.
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van Eijk M, Ferraz MJ, Boot RG, Aerts JMFG. Lyso-glycosphingolipids: presence and consequences. Essays Biochem 2020; 64:565-578. [PMID: 32808655 PMCID: PMC7517347 DOI: 10.1042/ebc20190090] [Citation(s) in RCA: 20] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/05/2020] [Revised: 07/14/2020] [Accepted: 07/17/2020] [Indexed: 12/12/2022]
Abstract
Lyso-glycosphingolipids are generated in excess in glycosphingolipid storage disorders. In the course of these pathologies glycosylated sphingolipid species accumulate within lysosomes due to flaws in the respective lipid degrading machinery. Deacylation of accumulating glycosphingolipids drives the formation of lyso-glycosphingolipids. In lysosomal storage diseases such as Gaucher Disease, Fabry Disease, Krabbe disease, GM1 -and GM2 gangliosidosis, Niemann Pick type C and Metachromatic leukodystrophy massive intra-lysosomal glycosphingolipid accumulation occurs. The lysosomal enzyme acid ceramidase generates the deacylated lyso-glycosphingolipid species. This review discusses how the various lyso-glycosphingolipids are synthesized, how they may contribute to abnormal immunity in glycosphingolipid storing lysosomal diseases and what therapeutic opportunities exist.
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Affiliation(s)
- Marco van Eijk
- Leiden Institute of Chemistry, Leiden University, Einsteinweg 55, 2300 RA, Leiden, The Netherlands
| | - Maria J Ferraz
- Leiden Institute of Chemistry, Leiden University, Einsteinweg 55, 2300 RA, Leiden, The Netherlands
| | - Rolf G Boot
- Leiden Institute of Chemistry, Leiden University, Einsteinweg 55, 2300 RA, Leiden, The Netherlands
| | - Johannes M F G Aerts
- Leiden Institute of Chemistry, Leiden University, Einsteinweg 55, 2300 RA, Leiden, The Netherlands
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Duarte C, Akkaoui J, Yamada C, Ho A, Mao C, Movila A. Elusive Roles of the Different Ceramidases in Human Health, Pathophysiology, and Tissue Regeneration. Cells 2020; 9:cells9061379. [PMID: 32498325 PMCID: PMC7349419 DOI: 10.3390/cells9061379] [Citation(s) in RCA: 18] [Impact Index Per Article: 4.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/18/2020] [Revised: 05/25/2020] [Accepted: 05/27/2020] [Indexed: 12/29/2022] Open
Abstract
Ceramide and sphingosine are important interconvertible sphingolipid metabolites which govern various signaling pathways related to different aspects of cell survival and senescence. The conversion of ceramide into sphingosine is mediated by ceramidases. Altogether, five human ceramidases—named acid ceramidase, neutral ceramidase, alkaline ceramidase 1, alkaline ceramidase 2, and alkaline ceramidase 3—have been identified as having maximal activities in acidic, neutral, and alkaline environments, respectively. All five ceramidases have received increased attention for their implications in various diseases, including cancer, Alzheimer’s disease, and Farber disease. Furthermore, the potential anti-inflammatory and anti-apoptotic effects of ceramidases in host cells exposed to pathogenic bacteria and viruses have also been demonstrated. While ceramidases have been a subject of study in recent decades, our knowledge of their pathophysiology remains limited. Thus, this review provides a critical evaluation and interpretive analysis of existing literature on the role of acid, neutral, and alkaline ceramidases in relation to human health and various diseases, including cancer, neurodegenerative diseases, and infectious diseases. In addition, the essential impact of ceramidases on tissue regeneration, as well as their usefulness in enzyme replacement therapy, is also discussed.
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Affiliation(s)
- Carolina Duarte
- Department of Periodontology, College of Dental Medicine, Nova Southeastern University, Fort Lauderdale, FL 33324, USA; (J.A.); (C.Y.); (A.H.)
- Correspondence: (C.D.); (A.M.); Tel.: +1-954-262-7306 (A.M.)
| | - Juliet Akkaoui
- Department of Periodontology, College of Dental Medicine, Nova Southeastern University, Fort Lauderdale, FL 33324, USA; (J.A.); (C.Y.); (A.H.)
| | - Chiaki Yamada
- Department of Periodontology, College of Dental Medicine, Nova Southeastern University, Fort Lauderdale, FL 33324, USA; (J.A.); (C.Y.); (A.H.)
| | - Anny Ho
- Department of Periodontology, College of Dental Medicine, Nova Southeastern University, Fort Lauderdale, FL 33324, USA; (J.A.); (C.Y.); (A.H.)
| | - Cungui Mao
- Department of Medicine, The State University of New York at Stony Brook, Stony Brook, NY 11794, USA;
- Cancer Center, The State University of New York at Stony Brook, Stony Brook, NY 11794, USA
| | - Alexandru Movila
- Department of Periodontology, College of Dental Medicine, Nova Southeastern University, Fort Lauderdale, FL 33324, USA; (J.A.); (C.Y.); (A.H.)
- Institute for Neuro-Immune Medicine, Nova Southeastern University, Fort Lauderdale, FL 33324, USA
- Correspondence: (C.D.); (A.M.); Tel.: +1-954-262-7306 (A.M.)
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Elsea SH, Solyom A, Martin K, Harmatz P, Mitchell J, Lampe C, Grant C, Selim L, Mungan NO, Guelbert N, Magnusson B, Sundberg E, Puri R, Kapoor S, Arslan N, DiRocco M, Zaki M, Ozen S, Mahmoud IG, Ehlert K, Hahn A, Gokcay G, Torcoletti M, Ferreira CR. ASAH1 pathogenic variants associated with acid ceramidase deficiency: Farber disease and spinal muscular atrophy with progressive myoclonic epilepsy. Hum Mutat 2020; 41:1469-1487. [PMID: 32449975 DOI: 10.1002/humu.24056] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/26/2019] [Revised: 04/28/2020] [Accepted: 05/16/2020] [Indexed: 11/12/2022]
Abstract
Farber disease and spinal muscular atrophy with progressive myoclonic epilepsy are a spectrum of rare lysosomal storage disorders characterized by acid ceramidase deficiency (ACD), resulting from pathogenic variants in N-acylsphingosine amidohydrolase 1 (ASAH1). Other than simple listings provided in literature reviews, a curated, comprehensive list of ASAH1 mutations associated with ACD clinical phenotypes has not yet been published. This publication includes mutations in ASAH1 collected through the Observational and Cross-Sectional Cohort Study of the Natural History and Phenotypic Spectrum of Farber Disease (NHS), ClinicalTrials.gov identifier NCT03233841, in combination with an up-to-date curated list of published mutations. The NHS is the first to collect retrospective and prospective data on living and deceased patients with ACD presenting as Farber disease, who had or had not undergone hematopoietic stem cell transplantation. Forty-five patients representing the known clinical spectrum of Farber disease (living patients aged 1-28 years) were enrolled. The curation of known ASAH1 pathogenic variants using a single reference transcript includes 10 previously unpublished from the NHS and 63 that were previously reported. The publication of ASAH1 variants will be greatly beneficial to patients undergoing genetic testing in the future by providing a significantly expanded reference list of disease-causing variants.
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Affiliation(s)
- Sarah H Elsea
- Molecular and Human Genetics, Baylor College of Medicine, Houston, Texas
| | | | - Kirt Martin
- Molecular and Human Genetics, Baylor College of Medicine, Houston, Texas
| | - Paul Harmatz
- Pediatric Gastroenterolgy and Nutrition, UCSF Benioff Children's Hospital Oakland, Oakland, California
| | | | | | | | - Laila Selim
- Cairo University Children's Hospital, Cairo, Egypt
| | | | | | - Bo Magnusson
- Karolinska University Hospital, Stockholm, Sweden
| | | | - Ratna Puri
- Sir Ganga Ram Hospital, New Delhi, India
| | - Seema Kapoor
- Lok Nayak Hospital and Maulana Azad Medical College, New Delhi, India
| | - Nur Arslan
- Dokuz Eylul University Hospital, Izmir, Turkey
| | - Maja DiRocco
- Metabolic Diseases, Istituto Giannina Gaslini, Genoa, Italy
| | - Maha Zaki
- Clinical Genetics Department, National Research Center, Cairo, Egypt
| | - Seza Ozen
- Pediatric Rheumatology, Hacettepe University Hospital, Ankara, Turkey
| | | | | | - Andreas Hahn
- UKGM Universitätsklinikum Giessen, Giessen, Germany
| | | | | | - Carlos R Ferreira
- National Human Genome Research Institute, National Institutes of Health, Bethesda, Maryland
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12
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Kyriakou K, W. Lederer C, Kleanthous M, Drousiotou A, Malekkou A. Acid Ceramidase Depletion Impairs Neuronal Survival and Induces Morphological Defects in Neurites Associated with Altered Gene Transcription and Sphingolipid Content. Int J Mol Sci 2020; 21:E1607. [PMID: 32111095 PMCID: PMC7084529 DOI: 10.3390/ijms21051607] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/27/2020] [Revised: 02/22/2020] [Accepted: 02/22/2020] [Indexed: 12/11/2022] Open
Abstract
The ASAH1 gene encodes acid ceramidase (AC), an enzyme that is implicated in the metabolism of ceramide (Cer). Mutations in the ASAH1 gene cause two different disorders, Farber disease (FD), a rare lysosomal storage disorder, and a rare form of spinal muscular atrophy combined with progressive myoclonic epilepsy (SMA-PME). In the absence of human in vitro neuronal disease models and to gain mechanistic insights into pathological effects of ASAH1 deficiency, we established and characterized a stable ASAH1 knockdown (ASAH1KD) SH-SY5Y cell line. ASAH1KD cells displayed reduced proliferation due to elevated apoptosis and G1/S cell cycle arrest. Distribution of LAMP1-positive lysosomes towards the cell periphery and significantly shortened and less branched neurites upon differentiation, implicate AC for lysosome positioning and neuronal development, respectively. Lipidomic analysis revealed changes in the intracellular levels of distinct sphingolipid species, importantly without Cer accumulation, in line with altered gene transcription within the sphingolipid pathway. Additionally, the transcript levels for Rho GTPases (RhoA, Rac1, and Cdc42), which are key regulators of axonal orientation, neurite branching and lysosome positioning were found to be dysregulated. This study shows the critical role of AC in neurons and suggests how AC depletion leads to defects seen in neuropathology of SMA-PME and FD.
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Affiliation(s)
- Kalia Kyriakou
- Cyprus School of Molecular Medicine, P.O. Box 23462, 1683 Nicosia, Cyprus; (K.K.); (C.W.L.); (M.K.); (A.D.)
- Biochemical Genetics Department, The Cyprus Institute of Neurology and Genetics, P.O. Box 23462, 1683 Nicosia, Cyprus
| | - Carsten W. Lederer
- Cyprus School of Molecular Medicine, P.O. Box 23462, 1683 Nicosia, Cyprus; (K.K.); (C.W.L.); (M.K.); (A.D.)
- Molecular Genetics Thalassaemia Department, The Cyprus Institute of Neurology and Genetics, P.O. Box 23462, 1683 Nicosia, Cyprus
| | - Marina Kleanthous
- Cyprus School of Molecular Medicine, P.O. Box 23462, 1683 Nicosia, Cyprus; (K.K.); (C.W.L.); (M.K.); (A.D.)
- Molecular Genetics Thalassaemia Department, The Cyprus Institute of Neurology and Genetics, P.O. Box 23462, 1683 Nicosia, Cyprus
| | - Anthi Drousiotou
- Cyprus School of Molecular Medicine, P.O. Box 23462, 1683 Nicosia, Cyprus; (K.K.); (C.W.L.); (M.K.); (A.D.)
- Biochemical Genetics Department, The Cyprus Institute of Neurology and Genetics, P.O. Box 23462, 1683 Nicosia, Cyprus
| | - Anna Malekkou
- Cyprus School of Molecular Medicine, P.O. Box 23462, 1683 Nicosia, Cyprus; (K.K.); (C.W.L.); (M.K.); (A.D.)
- Biochemical Genetics Department, The Cyprus Institute of Neurology and Genetics, P.O. Box 23462, 1683 Nicosia, Cyprus
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13
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The best evidence for progressive myoclonic epilepsy: A pathway to precision therapy. Seizure 2019; 71:247-257. [PMID: 31476531 DOI: 10.1016/j.seizure.2019.08.012] [Citation(s) in RCA: 46] [Impact Index Per Article: 9.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/16/2019] [Revised: 08/21/2019] [Accepted: 08/23/2019] [Indexed: 12/13/2022] Open
Abstract
Progressive Myoclonus Epilepsies (PMEs) are a group of uncommon clinically and genetically heterogeneous disorders characterised by myoclonus, generalized epilepsy, and neurological deterioration, including dementia and ataxia. PMEs may have infancy, childhood, juvenile or adult onset, but usually present in late childhood or adolescence, at variance from epileptic encephalopathies, which start with polymorphic seizures in early infancy. Neurophysiologic recordings are suited to describe faithfully the time course of the shock-like muscle contractions which characterize myoclonus. A combination of positive and negative myoclonus is typical of PMEs. The gene defects for most PMEs (Unverricht-Lundborg disease, Lafora disease, several forms of neuronal ceroid lipofuscinoses, myoclonus epilepsy with ragged-red fibers [MERRF], and type 1 and 2 sialidoses) have been identified. PMEs are uncommon disorders, difficult to diagnose in the absence of extensive experience. Thus, aetiology is undetermined in many patients, despite the advance in molecular medicine. Treatment of PMEs remains essentially symptomaticof seizures and myoclonus, together with palliative, supportive, and rehabilitative measures. The response to therapy may initially be relatively favourable, afterwards however, seizures may become more frequent, and progressive neurologic decline occurs. The prognosis of a PME depends on the specific disease. The history of PMEs revealed that the international collaboration and sharing experience is the right way to proceed. This emerging picture and biological insights will allow us to find ways to provide the patients with meaningful treatment.
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14
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Shervin Badv R, Nilipour Y, Rahimi-Dehgolan S, Rashidi-Nezhad A, Ghahvechi Akbari M. A novel case report of spinal muscular atrophy with progressive myoclonic epilepsy from Iran. Int Med Case Rep J 2019; 12:155-159. [PMID: 31213928 PMCID: PMC6549484 DOI: 10.2147/imcrj.s202046] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/18/2019] [Accepted: 04/09/2019] [Indexed: 11/23/2022] Open
Abstract
Spinal muscular atrophy (SMA) is a disorder characterized by decreased motor function due to the muscle atrophy in the background of degenerated anterior horn cells and motor cells of lower cranial nerves nuclei. The most frequent form is inherited as an autosomal recessive trait resulting from mutations in the survival motor neuron gene (SMN-1). On the other hand, a rare variant of this condition, named progressive myoclonic epilepsy subtype (SMA-PME) occurs in the result of a mutation in N-acylsphingosine amidohydrolase-1 gene (ASAH-1). The latter gene is responsible for lysosomal acid-ceramidase production. SMA-PME has been characterized by a progressive muscle weakness from ages 3–7 years, accompanied by epilepsy, an intractable seizure, and sometimes sensorineural hearing loss. In this report, we have presented a 15-year old female patient with SMA-PME that was attended to neurology clinic for a new onset tremor, seizure and proximal weakness in all limbs. We identified a homozygous mutation in exon II on her ASAH-1 gene [c.173C>T (p. Thr58Met)]. Also, a modest reduction was found in ceramidase-activity. As was expected patient`s seizures did not respond to conventional therapies.
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Affiliation(s)
- Reza Shervin Badv
- Children's Medical Center, Pediatrics Center of Excellence, Tehran University of Medical Sciences (TUMS), Tehran, Iran
| | - Yalda Nilipour
- Pediatric Pathology Research center, Research Institute for Children Health, Mofid Hospital, Shahid Beheshti University of Medical Sciences, Tehran, Iran
| | - Shahram Rahimi-Dehgolan
- Physical Medicine and Rehabilitation Department, Imam Khomeini Hospital Complex (IKHC), Tehran University of Medical Sciences (TUMS), Tehran, Iran
| | - Ali Rashidi-Nezhad
- Maternal, Fetal and Neonatal Research Center, Imam khomeini Hospital Complex, Tehran University of Medical Sciences, Tehran, Iran
| | - Masood Ghahvechi Akbari
- Physical Medicine and Rehabilitation Department, Children's Medical Center, Tehran University of Medical Sciences (TUMS), Tehran, Iran
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15
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A new case of SMA phenotype without epilepsy due to biallelic variants in ASAH1. Eur J Hum Genet 2018; 27:337-339. [PMID: 30291339 DOI: 10.1038/s41431-018-0250-z] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/18/2018] [Revised: 08/03/2018] [Accepted: 08/09/2018] [Indexed: 11/08/2022] Open
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16
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Yu FPS, Amintas S, Levade T, Medin JA. Acid ceramidase deficiency: Farber disease and SMA-PME. Orphanet J Rare Dis 2018; 13:121. [PMID: 30029679 PMCID: PMC6053731 DOI: 10.1186/s13023-018-0845-z] [Citation(s) in RCA: 65] [Impact Index Per Article: 10.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/19/2018] [Accepted: 06/14/2018] [Indexed: 12/29/2022] Open
Abstract
Acid ceramidase (ACDase) deficiency is a spectrum of disorders that includes a rare lysosomal storage disorder called Farber disease (FD) and a rare epileptic disorder called spinal muscular atrophy with progressive myoclonic epilepsy (SMA-PME). Both disorders are caused by mutations in the ASAH1 gene that encodes the lysosomal hydrolase that breaks down the bioactive lipid ceramide. To date, there have been fewer than 200 reported cases of FD and SMA-PME in the literature. Typical textbook manifestations of classical FD include the formation of subcutaneous nodules, accumulation of joint contractures, and development of a hoarse voice. In reality, however, the clinical presentation is much broader. Patients may develop severe pathologies leading to death in infancy or may develop attenuated forms of the disorder wherein they are often misdiagnosed or not diagnosed until adulthood. A clinical variability also exists for SMA-PME, in which patients develop progressive muscle weakness and seizures. Currently, there is no known cure for FD or for SMA-PME. The main treatment is symptom management. In rare cases, treatment may include surgery or hematopoietic stem cell transplantation. Research using disease models has provided insights into the pathology as well as the role of ACDase in the development of these conditions. Recent studies have highlighted possible biomarkers for an effective diagnosis of ACDase deficiency. Ongoing work is being conducted to evaluate the use of recombinant human ACDase (rhACDase) for the treatment of FD. Finally, gene therapy strategies for the treatment of ACDase deficiency are actively being pursued. This review highlights the broad clinical definition and outlines key studies that have improved our understanding of inherited ACDase deficiency-related conditions.
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Affiliation(s)
- Fabian P S Yu
- Institute of Medical Science, University of Toronto, Toronto, ON, Canada
| | - Samuel Amintas
- Laboratoire de Biochimie Métabolique, Institut Fédératif de Biologie, CHU Purpan, Toulouse, France
| | - Thierry Levade
- Laboratoire de Biochimie Métabolique, Institut Fédératif de Biologie, CHU Purpan, Toulouse, France. .,INSERM UMR1037 CRCT, Université de Toulouse, Toulouse, France.
| | - Jeffrey A Medin
- Institute of Medical Science, University of Toronto, Toronto, ON, Canada. .,Departments of Pediatrics and Biochemistry, Medical College of Wisconsin, Milwaukee, WI, USA.
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17
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Nardone R, Versace V, Höller Y, Sebastianelli L, Brigo F, Lochner P, Golaszewski S, Saltuari L, Trinka E. Transcranial magnetic stimulation in myoclonus of different aetiologies. Brain Res Bull 2018; 140:258-269. [DOI: 10.1016/j.brainresbull.2018.05.016] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/22/2018] [Revised: 05/12/2018] [Accepted: 05/18/2018] [Indexed: 12/29/2022]
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18
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Awaguni H, Shinozuka J, Tanaka SI, Kadowaki S, Makino S, Maruyama R, Shigematsu Y, Hamaoka K, Imashuku S. Acute encephalopathy with biphasic seizures and late reduced diffusion associated with Streptococcus sanguinis sepsis. Pediatr Rep 2018; 10:7424. [PMID: 29721246 PMCID: PMC5907728 DOI: 10.4081/pr.2018.7424] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 09/29/2017] [Revised: 01/20/2018] [Accepted: 02/12/2018] [Indexed: 11/22/2022] Open
Abstract
Acute encephalopathy with biphasic seizures and late reduced diffusion (AESD) develops in association with systemic as well as central nervous system (CNS) viral or bacterial infections. AESD is most often noted with influenza or human herpesvirus 6 infection in previously healthy infants. However, AESD has also been reported in an infant with developmental retardation and in a mentally and motor-disabled adolescent. Here, we report the case of a 4- year-old female with significant development delay due to spinal muscular atrophy, who developed AESD during Streptococcus sanguinis sepsis with no apparent CNS infection. Although the patient had extremely high serum procalcitonin (45.84 ng/mL, reference; <0.4) on admission indicating a poor prognosis, she was successfully managed for sepsis and AESD.
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Affiliation(s)
- Hitoshi Awaguni
- Division of Pediatrics, Uji-Tokushukai Medical Center, Uji, Kyoto, Japan
| | - Jun Shinozuka
- Division of Pediatrics, Uji-Tokushukai Medical Center, Uji, Kyoto, Japan
| | - Shin-Ichiro Tanaka
- Division of Pediatrics, Uji-Tokushukai Medical Center, Uji, Kyoto, Japan
| | - Sayaka Kadowaki
- Division of Pediatrics, Uji-Tokushukai Medical Center, Uji, Kyoto, Japan
| | - Shigeru Makino
- Division of Pediatrics, Uji-Tokushukai Medical Center, Uji, Kyoto, Japan
| | - Rikken Maruyama
- Division of Pediatrics, Uji-Tokushukai Medical Center, Uji, Kyoto, Japan
| | - Yosuke Shigematsu
- Division of Pediatrics, Uji-Tokushukai Medical Center, Uji, Kyoto, Japan
| | - Kenji Hamaoka
- Division of Pediatrics, Uji-Tokushukai Medical Center, Uji, Kyoto, Japan
| | - Shinsaku Imashuku
- Division of Pediatrics, Uji-Tokushukai Medical Center, Uji, Kyoto, Japan
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19
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Olsen ASB, Færgeman NJ. Sphingolipids: membrane microdomains in brain development, function and neurological diseases. Open Biol 2018; 7:rsob.170069. [PMID: 28566300 PMCID: PMC5451547 DOI: 10.1098/rsob.170069] [Citation(s) in RCA: 193] [Impact Index Per Article: 32.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/21/2017] [Accepted: 04/30/2017] [Indexed: 12/11/2022] Open
Abstract
Sphingolipids are highly enriched in the nervous system where they are pivotal constituents of the plasma membranes and are important for proper brain development and functions. Sphingolipids are not merely structural elements, but are also recognized as regulators of cellular events by their ability to form microdomains in the plasma membrane. The significance of such compartmentalization spans broadly from being involved in differentiation of neurons and synaptic transmission to neuronal–glial interactions and myelin stability. Thus, perturbations of the sphingolipid metabolism can lead to rearrangements in the plasma membrane, which has been linked to the development of various neurological diseases. Studying microdomains and their functions has for a long time been synonymous with studying the role of cholesterol. However, it is becoming increasingly clear that microdomains are very heterogeneous, which among others can be ascribed to the vast number of sphingolipids. In this review, we discuss the importance of microdomains with emphasis on sphingolipids in brain development and function as well as how disruption of the sphingolipid metabolism (and hence microdomains) contributes to the pathogenesis of several neurological diseases.
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Affiliation(s)
- Anne S B Olsen
- Villum Center for Bioanalytical Sciences, Department of Biochemistry and Molecular Biology, University of Southern Denmark, 5230 Odense M, Denmark
| | - Nils J Færgeman
- Villum Center for Bioanalytical Sciences, Department of Biochemistry and Molecular Biology, University of Southern Denmark, 5230 Odense M, Denmark
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20
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de Souza PVS, Bortholin T, Naylor FGM, Chieia MAT, de Rezende Pinto WBV, Oliveira ASB. Motor neuron disease in inherited neurometabolic disorders. Rev Neurol (Paris) 2017; 174:115-124. [PMID: 29128155 DOI: 10.1016/j.neurol.2017.06.020] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/18/2017] [Revised: 04/29/2017] [Accepted: 06/15/2017] [Indexed: 01/18/2023]
Abstract
Inherited neurometabolic disorders represent a growing group of inborn errors of metabolism that present with major neurological symptoms or a complex spectrum of symptoms dominated by central or peripheral nervous system dysfunction. Many neurological presentations may arise from the same metabolic defect, especially in autosomal-recessive inherited disorders. Motor neuron disease (MND), mainly represented by amyotrophic lateral sclerosis, may also result from various inborn errors of metabolism, some of which may represent potentially treatable conditions, thereby emphasizing the importance of recognizing such diseases. The present review discusses the most important neurometabolic disorders presenting with motor neuron (lower and/or upper) dysfunction as the key clinical and neuropathological feature.
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Affiliation(s)
- P Victor Sgobbi de Souza
- Division of Neuromuscular Diseases, Department of Neurology and Neurosurgery, Federal University of São Paulo (UNIFESP), São Paulo, SP, Brazil
| | - T Bortholin
- Division of Neuromuscular Diseases, Department of Neurology and Neurosurgery, Federal University of São Paulo (UNIFESP), São Paulo, SP, Brazil
| | - F George Monteiro Naylor
- Division of Neuromuscular Diseases, Department of Neurology and Neurosurgery, Federal University of São Paulo (UNIFESP), São Paulo, SP, Brazil
| | - M Antônio Troccoli Chieia
- Division of Neuromuscular Diseases, Department of Neurology and Neurosurgery, Federal University of São Paulo (UNIFESP), São Paulo, SP, Brazil
| | - W Bocca Vieira de Rezende Pinto
- Division of Neuromuscular Diseases, Department of Neurology and Neurosurgery, Federal University of São Paulo (UNIFESP), São Paulo, SP, Brazil.
| | - A Souza Bulle Oliveira
- Division of Neuromuscular Diseases, Department of Neurology and Neurosurgery, Federal University of São Paulo (UNIFESP), São Paulo, SP, Brazil
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21
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Dodge JC. Lipid Involvement in Neurodegenerative Diseases of the Motor System: Insights from Lysosomal Storage Diseases. Front Mol Neurosci 2017; 10:356. [PMID: 29163032 PMCID: PMC5675881 DOI: 10.3389/fnmol.2017.00356] [Citation(s) in RCA: 25] [Impact Index Per Article: 3.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/21/2017] [Accepted: 10/19/2017] [Indexed: 12/11/2022] Open
Abstract
Lysosomal storage diseases (LSDs) are a heterogeneous group of rare inherited metabolic diseases that are frequently triggered by the accumulation of lipids inside organelles of the endosomal-autophagic-lysosomal system (EALS). There is now a growing realization that disrupted lysosomal homeostasis (i.e., lysosomal cacostasis) also contributes to more common neurodegenerative disorders such as Parkinson disease (PD). Lipid deposition within the EALS may also participate in the pathogenesis of some additional neurodegenerative diseases of the motor system. Here, I will highlight the lipid abnormalities and clinical manifestations that are common to LSDs and several diseases of the motor system, including amyotrophic lateral sclerosis (ALS), atypical forms of spinal muscular atrophy, Charcot-Marie-Tooth disease (CMT), hereditary spastic paraplegia (HSP), multiple system atrophy (MSA), PD and spinocerebellar ataxia (SCA). Elucidating the underlying basis of intracellular lipid mislocalization as well as its consequences in each of these disorders will likely provide innovative targets for therapeutic research.
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Affiliation(s)
- James C Dodge
- Neuroscience Therapeutic Area, Sanofi, Framingham, MA, United States
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22
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Schuchman EH, Mitchell J, Solyom A. Morbidity and mortality associated with Farber disease and prospects for therapy. Expert Opin Orphan Drugs 2017. [DOI: 10.1080/21678707.2017.1359086] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 01/21/2023]
Affiliation(s)
- Edward H. Schuchman
- Genetic Disease Foundation-Francis Crick Professor, Department of Genetics & Genomic Sciences, Icahn School of Medicine, New York, NY, USA
| | - John Mitchell
- Division of Pediatric Endocrinology, Montreal Children’s Hospital, Montreal, QC, Canada
| | - Alex Solyom
- Clinical Research & Patient Affairs, Enzyvant, Basel, Switzerland
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23
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Abstract
Genetic and acquired motor-neuron-disorders (MNDs) may undergo acute deterioration resulting in various emergency situations. This literature review aims at summarising and discussing current knowledge about emergencies in MNDs. Emergencies that have been reported in MND patients include: respiratory, bulbar, cardiac, septic, epileptic, psychiatric, pain-related, and traumatic emergencies. Emergencies due to respiratory insufficiency have the strongest impact on morbidity and mortality in MNDs. To optimise the management of emergencies in MNDs, it is recommended to discuss these topics with the patient prior to their occurrence. After informed consent, patients may indicate their decision by signing an advance directive as to how such emergencies should be managed in case they arise. Generally, treatment of emergencies in MNDs is not at variance from treatment of similar emergencies due to other causes, but some peculiarities need to be pointed out. It is concluded that patients with MNDs may experience various emergencies during the disease course. Management of these conditions should be discussed with the patient prior to their appearance. Management of these emergencies follows general guidelines, which widely vary between countries, and depend on the availability of a patient's advance directive.
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Affiliation(s)
- Josef Finsterer
- Krankenanstalt Rudolfstiftung, Postfach 20, 1180, Vienna, Austria.
| | - Claudia Stöllberger
- 2nd Medical Department with Cardiology and Intensive Care Medicine, Krankenanstalt Rudolfstiftung, Vienna, Austria
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24
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Abstract
Paediatric motor neuron diseases encompass a group of neurodegenerative diseases characterised by the onset of muscle weakness and atrophy before the age of 18 years, attributable to motor neuron loss across various neuronal networks in the brain and spinal cord. While the genetic underpinnings are diverse, advances in next generation sequencing have transformed diagnostic paradigms. This has reinforced the clinical phenotyping and molecular genetic expertise required to navigate the complexities of such diagnoses. In turn, improved genetic technology and subsequent gene identification have enabled further insights into the mechanisms of motor neuron degeneration and how these diseases form part of a neurodegenerative disorder spectrum. Common pathophysiologies include abnormalities in axonal architecture and function, RNA processing, and protein quality control. This review incorporates an overview of the clinical manifestations, genetics, and pathophysiology of inherited paediatric motor neuron disorders beyond classic SMN1-related spinal muscular atrophy and describes recent advances in next generation sequencing and its clinical application. Specific disease-modifying treatment is becoming a clinical reality in some disorders of the motor neuron highlighting the importance of a timely and specific diagnosis.
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25
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Sikora J, Dworski S, Jones EE, Kamani MA, Micsenyi MC, Sawada T, Le Faouder P, Bertrand-Michel J, Dupuy A, Dunn CK, Xuan ICY, Casas J, Fabrias G, Hampson DR, Levade T, Drake RR, Medin JA, Walkley SU. Acid Ceramidase Deficiency in Mice Results in a Broad Range of Central Nervous System Abnormalities. THE AMERICAN JOURNAL OF PATHOLOGY 2017; 187:864-883. [PMID: 28342444 DOI: 10.1016/j.ajpath.2016.12.005] [Citation(s) in RCA: 32] [Impact Index Per Article: 4.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/09/2016] [Revised: 12/02/2016] [Accepted: 12/08/2016] [Indexed: 12/30/2022]
Abstract
Farber disease is a rare autosomal recessive disorder caused by acid ceramidase deficiency that usually presents as early-onset progressive visceral and neurologic disease. To understand the neurologic abnormality, we investigated behavioral, biochemical, and cellular abnormalities in the central nervous system of Asah1P361R/P361R mice, which serve as a model of Farber disease. Behaviorally, the mutant mice had reduced voluntary locomotion and exploration, increased thigmotaxis, abnormal spectra of basic behavioral activities, impaired muscle grip strength, and defects in motor coordination. A few mutant mice developed hydrocephalus. Mass spectrometry revealed elevations of ceramides, hydroxy-ceramides, dihydroceramides, sphingosine, dihexosylceramides, and monosialodihexosylganglioside in the brain. The highest accumulation was in hydroxy-ceramides. Storage compound distribution was analyzed by mass spectrometry imaging and morphologic analyses and revealed involvement of a wide range of central nervous system cell types (eg, neurons, endothelial cells, and choroid plexus cells), most notably microglia and/or macrophages. Coalescing and mostly perivascular granuloma-like accumulations of storage-laden CD68+ microglia and/or macrophages were seen as early as 3 weeks of age and located preferentially in white matter, periventricular zones, and meninges. Neurodegeneration was also evident in specific cerebral areas in late disease. Overall, our central nervous system studies in Asah1P361R/P361R mice substantially extend the understanding of human Farber disease and suggest that this model can be used to advance therapeutic approaches for this currently untreatable disorder.
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Affiliation(s)
- Jakub Sikora
- Dominick P. Purpura Department of Neuroscience, Rose F. Kennedy Intellectual and Developmental Disabilities Research Center, Albert Einstein College of Medicine, Bronx, New York; Institute of Inherited Metabolic Disorders, Charles University, 1st Faculty of Medicine, Prague, Czech Republic; Institute of Pathology, Charles University, 1st Faculty of Medicine, Prague, Czech Republic
| | - Shaalee Dworski
- Institute of Medical Science, University of Toronto, Toronto, Ontario, Canada
| | - E Ellen Jones
- Department of Cell and Molecular Pharmacology, Medical University of South Carolina, Charleston, South Carolina
| | | | - Matthew C Micsenyi
- Dominick P. Purpura Department of Neuroscience, Rose F. Kennedy Intellectual and Developmental Disabilities Research Center, Albert Einstein College of Medicine, Bronx, New York
| | - Tomo Sawada
- Dominick P. Purpura Department of Neuroscience, Rose F. Kennedy Intellectual and Developmental Disabilities Research Center, Albert Einstein College of Medicine, Bronx, New York
| | - Pauline Le Faouder
- MetaToul-Lipidomic Facility-MetaboHUB, INSERM UMR1048, Institute of Cardiovascular and Metabolic Diseases, Université Paul Sabatier-Toulouse III, Toulouse, France
| | - Justine Bertrand-Michel
- MetaToul-Lipidomic Facility-MetaboHUB, INSERM UMR1048, Institute of Cardiovascular and Metabolic Diseases, Université Paul Sabatier-Toulouse III, Toulouse, France
| | - Aude Dupuy
- MetaToul-Lipidomic Facility-MetaboHUB, INSERM UMR1048, Institute of Cardiovascular and Metabolic Diseases, Université Paul Sabatier-Toulouse III, Toulouse, France
| | | | - Ingrid Cong Yang Xuan
- Department of Pharmaceutical Sciences, University of Toronto, Toronto, Ontario, Canada
| | - Josefina Casas
- Research Unit on Bioactive Molecules, Department of Biomedicinal Chemistry, Institute for Advanced Chemistry of Catalonia, Spanish National Research Council, Barcelona, Spain
| | - Gemma Fabrias
- Research Unit on Bioactive Molecules, Department of Biomedicinal Chemistry, Institute for Advanced Chemistry of Catalonia, Spanish National Research Council, Barcelona, Spain
| | - David R Hampson
- Department of Pharmaceutical Sciences, University of Toronto, Toronto, Ontario, Canada
| | - Thierry Levade
- INSERM UMR1037, Cancer Research Center of Toulouse, Universite Toulouse III Paul-Sabatier, Toulouse, France; Metabolic Biochemistry Laboratory, Federative Institute of Biology, Centre Hospitalier Universitaire de Toulouse, Toulouse, France
| | - Richard R Drake
- Department of Cell and Molecular Pharmacology, Medical University of South Carolina, Charleston, South Carolina
| | - Jeffrey A Medin
- Institute of Medical Science, University of Toronto, Toronto, Ontario, Canada; University Health Network, Toronto, Ontario, Canada; Department of Medical Biophysics, University of Toronto, Toronto, Ontario, Canada; Medical College of Wisconsin, Milwaukee, Wisconsin.
| | - Steven U Walkley
- Dominick P. Purpura Department of Neuroscience, Rose F. Kennedy Intellectual and Developmental Disabilities Research Center, Albert Einstein College of Medicine, Bronx, New York.
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26
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Dworski S, Lu P, Khan A, Maranda B, Mitchell JJ, Parini R, Di Rocco M, Hugle B, Yoshimitsu M, Magnusson B, Makay B, Arslan N, Guelbert N, Ehlert K, Jarisch A, Gardner-Medwin J, Dagher R, Terreri MT, Lorenco CM, Barillas-Arias L, Tanpaiboon P, Solyom A, Norris JS, He X, Schuchman EH, Levade T, Medin JA. Acid Ceramidase Deficiency is characterized by a unique plasma cytokine and ceramide profile that is altered by therapy. Biochim Biophys Acta Mol Basis Dis 2016; 1863:386-394. [PMID: 27915031 DOI: 10.1016/j.bbadis.2016.11.031] [Citation(s) in RCA: 30] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/07/2016] [Revised: 11/17/2016] [Accepted: 11/30/2016] [Indexed: 12/21/2022]
Abstract
Acid Ceramidase Deficiency (Farber disease, FD) is an ultra-rare Lysosomal Storage Disorder that is poorly understood and often misdiagnosed as Juvenile Idiopathic Arthritis (JIA). Hallmarks of FD are accumulation of ceramides, widespread macrophage infiltration, splenomegaly, and lymphocytosis. The cytokines involved in this abnormal hematopoietic state are unknown. There are dozens of ceramide species and derivatives, but the specific ones that accumulate in FD have not been investigated. We used a multiplex assay to analyze cytokines and mass spectrometry to analyze ceramides in plasma from patients and mice with FD, controls, Farber patients treated by hematopoietic stem cell transplantation (HSCT), JIA patients, and patients with Gaucher disease. KC, MIP-1α, and MCP-1 were sequentially upregulated in plasma from FD mice. MCP-1, IL-10, IL-6, IL-12, and VEGF levels were elevated in plasma from Farber patients but not in control or JIA patients. C16-Ceramide (C16-Cer) and dhC16-Cer were upregulated in plasma from FD mice. a-OH-C18-Cer, dhC12-Cer, dhC24:1-Cer, and C22:1-Cer-1P accumulated in plasma from patients with FD. Most cytokines and only a-OH-C18-Cer returned to baseline levels in HSCT-treated Farber patients. Sphingosines were not altered. Chitotriosidase activity was also relatively low. A unique cytokine and ceramide profile was seen in the plasma of Farber patients that was not observed in plasma from HSCT-treated Farber patients, JIA patients, or Gaucher patients. The cytokine profile can potentially be used to prevent misdiagnosis of Farber as JIA and to monitor the response to treatment. Further understanding of why these signaling molecules and lipids are elevated can lead to better understanding of the etiology and pathophysiology of FD and inform development of future treatments.
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Affiliation(s)
- Shaalee Dworski
- Institute of Medical Science, University of Toronto, Toronto M5G 1L7, Canada
| | - Ping Lu
- Department of Microbiology and Immunology, Hollings Cancer Center, Medical University of South Carolina, Charleston, SC 29425-5040, USA
| | - Aneal Khan
- Medical Genetics and Pediatrics, University of Calgary, Alberta Children's Hospital, Calgary T3B 6A8, Canada
| | - Bruno Maranda
- Department of Genetics, Centre Hospitalier Universitaire de Sherbrooke, Sherbrooke J1G 2E8, Canada
| | - John J Mitchell
- Department of Medical Genetics, McGill University, Montréal H3A 0G4, Canada; Department of Pediatrics, McGill University, Montréal H3A 0G4, Canada
| | - Rossella Parini
- Pediatric Department, University Milano Bicocca, San Gerardo Hospital, Monza 20126, Italy
| | | | - Boris Hugle
- German Center for Paediatric and Adolescent Rheumatology, Garmisch-Partenkirchen 82467, Germany
| | - Makoto Yoshimitsu
- Division of Hematology and Immunology, Center for Chronic Viral Diseases, Graduate School of Medical and Dental Sciences, Kagoshima University, Kagoshima 890-8544, Japan
| | - Bo Magnusson
- Pediatric Rheumatology, Karolinska University Hospital, Stockholm 171 76, Sweden
| | - Balahan Makay
- Pediatric Rheumatology, Dokuz Eylul University, Izmir 35210, Turkey
| | - Nur Arslan
- Gastroenterology and Metabolic Diseases, Dokuz Eylul University, Izmir 35210, Turkey
| | | | - Karoline Ehlert
- Department of Paediatric Oncology and Haematology, Medical University of Greifswald, Greifswald 17475, Germany
| | - Andrea Jarisch
- Department of Paediatric Oncology and Haematology, Goethe University, Frankfurt 60323, Germany
| | - Janet Gardner-Medwin
- Pediatric Rheumatology, University of Glasgow, Glasgow G12 8QQ, Scotland, United Kingdom
| | - Rawane Dagher
- Pediatric Rheumatology, Notre Dame De Secours University Hospital, Byblos, Lebanon
| | - Maria Teresa Terreri
- Pediatric Rheumatology, Federal University of Sao Paulo, Sao Paulo 04023-900, Brazil
| | - Charles Marques Lorenco
- Neurogenetics, Hospital of Ribeirao Preto, University of Sao Paulo, Sao Paulo 04023-900, Brazil
| | - Lilianna Barillas-Arias
- Pediatric Rheumatology, Bernard & Millie Duker Children's Hospital, Albany Medical Center, Albany, NY 12208, USA
| | - Pranoot Tanpaiboon
- Metabolic Diseases, Children's National Health System, Washington, DC 20010, USA
| | | | - James S Norris
- Department of Microbiology and Immunology, Hollings Cancer Center, Medical University of South Carolina, Charleston, SC 29425-5040, USA
| | - Xingxuan He
- Department of Genetics and Genomic Sciences, Icahn School of Medicine at Mount Sinai, New York, NY 10029-6574, USA
| | - Edward H Schuchman
- Plexcera Therapeutics, New York, NY 10029-6574, USA; Department of Genetics and Genomic Sciences, Icahn School of Medicine at Mount Sinai, New York, NY 10029-6574, USA
| | - Thierry Levade
- Laboratoire de Biochimie Métabolique, Institut Fédératif de Biologie, CHU Purpan, and INSERM UMR1037 CRCT, Toulouse 31037 Cedex 1, France
| | - Jeffrey A Medin
- Institute of Medical Science, University of Toronto, Toronto M5G 1L7, Canada; Department of Medical Biophysics, University of Toronto, Toronto M5G 1L7, Canada; University Health Network, Toronto M5G 1L7, Canada; Medical College of Wisconsin, Milwaukee, WI 53226, USA.
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27
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Schuchman EH. Acid ceramidase and the treatment of ceramide diseases: The expanding role of enzyme replacement therapy. Biochim Biophys Acta Mol Basis Dis 2016; 1862:1459-71. [PMID: 27155573 DOI: 10.1016/j.bbadis.2016.05.001] [Citation(s) in RCA: 32] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/17/2016] [Revised: 04/18/2016] [Accepted: 05/03/2016] [Indexed: 01/20/2023]
Abstract
Ceramides are a diverse group of sphingolipids that play important roles in many biological processes. Acid ceramidase (AC) is one key enzyme that regulates ceramide metabolism. Early research on AC focused on the fact that it is the enzyme deficient in the rare genetic disorder, Farber Lipogranulomatosis. Recent research has revealed that deficiency of the same enzyme is responsible for a rare form of spinal muscular atrophy associated with myoclonic epilepsy (SMA-PME). Due to their diverse role in biology, accumulation of ceramides also has been implicated in the pathobiology of many other common diseases, including infectious lung diseases, diabetes, cancers and others. This has revealed the potential of AC as a therapy for many of these diseases. This review will focus on the biology of AC and the potential role of this enzyme in the treatment of human disease.
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Affiliation(s)
- Edward H Schuchman
- Department of Genetics and Genomic Sciences, Icahn School of Medicine at Mount Sinai, New York, NY, USA.
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28
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Filosto M, Aureli M, Castellotti B, Rinaldi F, Schiumarini D, Valsecchi M, Lualdi S, Mazzotti R, Pensato V, Rota S, Gellera C, Filocamo M, Padovani A. ASAH1 variant causing a mild SMA phenotype with no myoclonic epilepsy: a clinical, biochemical and molecular study. Eur J Hum Genet 2016; 24:1578-1583. [PMID: 27026573 DOI: 10.1038/ejhg.2016.28] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/30/2015] [Revised: 02/03/2016] [Accepted: 03/01/2016] [Indexed: 11/09/2022] Open
Abstract
ASAH1 gene encodes for acid ceramidase that is involved in the degradation of ceramide into sphingosine and free fatty acids within lysosomes. ASAH1 variants cause both the severe and early-onset Farber disease and rare cases of spinal muscular atrophy (SMA) with progressive myoclonic epilepsy (SMA-PME), phenotypically characterized by childhood onset of proximal muscle weakness and atrophy due to spinal motor neuron degeneration followed by occurrence of severe and intractable myoclonic seizures and death in the teenage years. We studied two subjects, a 30-year-old pregnant woman and her 17-year-old sister, affected with a very slowly progressive non-5q SMA since childhood. No history of seizures or myoclonus has been reported and EEG was unremarkable. The molecular study of ASAH1 gene showed the presence of the homozygote nucleotide variation c.124A>G (r.124a>g) that causes the amino acid substitution p.Thr42Ala. Biochemical evaluation of cultured fibroblasts showed both reduction in ceramidase activity and accumulation of ceramide compared with the normal control. This study describes for the first time the association between ASAH1 variants and an adult SMA phenotype with no myoclonic epilepsy nor death in early age, thus expanding the phenotypic spectrum of ASAH1-related SMA. ASAH1 molecular analysis should be considered in the diagnostic testing of non-5q adult SMA patients.
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Affiliation(s)
- Massimiliano Filosto
- Clinical Neurology, Section for Neuromuscular Diseases and Neuropathies, University Hospital 'Spedali Civili', Brescia, Italy
| | - Massimo Aureli
- Department of Medical Biotechnology and Translational Medicine, University of Milan, Milan, Italy
| | - Barbara Castellotti
- Unit of Genetics of Neurodegenerative and Metabolic Diseases, Fondazione IRCCS Istituto Neurologico 'Carlo Besta', Milan, Italy
| | - Fabrizio Rinaldi
- Clinical Neurology, Section for Neuromuscular Diseases and Neuropathies, University Hospital 'Spedali Civili', Brescia, Italy
| | - Domitilla Schiumarini
- Department of Medical Biotechnology and Translational Medicine, University of Milan, Milan, Italy
| | - Manuela Valsecchi
- Department of Medical Biotechnology and Translational Medicine, University of Milan, Milan, Italy
| | - Susanna Lualdi
- Centro di Diagnostica Genetica e Biochimica delle Malattie Metaboliche, Istituto Giannina Gaslini, Genova, Italy
| | - Raffaella Mazzotti
- Centro di Diagnostica Genetica e Biochimica delle Malattie Metaboliche, Istituto Giannina Gaslini, Genova, Italy
| | - Viviana Pensato
- Unit of Genetics of Neurodegenerative and Metabolic Diseases, Fondazione IRCCS Istituto Neurologico 'Carlo Besta', Milan, Italy
| | - Silvia Rota
- Clinical Neurology, Section for Neuromuscular Diseases and Neuropathies, University Hospital 'Spedali Civili', Brescia, Italy
| | - Cinzia Gellera
- Unit of Genetics of Neurodegenerative and Metabolic Diseases, Fondazione IRCCS Istituto Neurologico 'Carlo Besta', Milan, Italy
| | - Mirella Filocamo
- Centro di Diagnostica Genetica e Biochimica delle Malattie Metaboliche, Istituto Giannina Gaslini, Genova, Italy
| | - Alessandro Padovani
- Clinical Neurology, Section for Neuromuscular Diseases and Neuropathies, University Hospital 'Spedali Civili', Brescia, Italy
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29
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Acid ceramidase deficiency associated with spinal muscular atrophy with progressive myoclonic epilepsy. Neuromuscul Disord 2015; 25:959-63. [PMID: 26526000 DOI: 10.1016/j.nmd.2015.09.007] [Citation(s) in RCA: 27] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/26/2015] [Revised: 09/03/2015] [Accepted: 09/07/2015] [Indexed: 11/22/2022]
Abstract
Spinal muscular atrophy with progressive myoclonic epilepsy (SMA-PME) is an extremely rare disorder related to the lysosomal storage disease, Farber lipogranulomatosis. Both disorders are autosomal recessive conditions caused by mutations in the ASAH1 gene encoding acid ceramidase. Farber disease is associated with joint deformities, lipomatous skin nodules, and often is fatal by 2-3 years of age; while SMA-PME is characterized by childhood-onset motor neuron disease and progressive myoclonic epilepsy. We report a case of SMA-PME with a novel mutation in the ASAH1 gene encoding acid ceramidase. The proband presented with childhood-onset of diffuse muscle atrophy and hypotonia. He also had diffuse weakness with greater proximal than distal involvement. Tongue fasciculations were present and his reflexes were either diminished or absent. He ambulated with an unsteady and hesitant gait. He subsequently developed myoclonic epilepsy along with other associated features including tremor, polymyoclonus, and sensorineural hearing loss. Neurophysiological studies revealed a motor neuron disorder and generalized epilepsy. Exome sequencing analysis identified compound heterozygous variants and biochemical analysis indicated acid ceramidase activity was approximately 12 percent of normal controls. Our proband was phenotypically similar to other cases of SMA-PME, albeit with somewhat lesser severity, slower progression, and greater longevity. As lysosomal disorders are sometimes amendable to early interventions, it is important to make early diagnoses in these cases. The combination of motor neuron disease and progressive myoclonic epilepsy should prompt genetic evaluation of ASAH1.
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