1
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Tolerico M, Merscher S, Fornoni A. Normal and Dysregulated Sphingolipid Metabolism: Contributions to Podocyte Injury and Beyond. Cells 2024; 13:890. [PMID: 38891023 PMCID: PMC11171506 DOI: 10.3390/cells13110890] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/26/2024] [Revised: 05/09/2024] [Accepted: 05/16/2024] [Indexed: 06/20/2024] Open
Abstract
Podocyte health is vital for maintaining proper glomerular filtration in the kidney. Interdigitating foot processes from podocytes form slit diaphragms which regulate the filtration of molecules through size and charge selectivity. The abundance of lipid rafts, which are ordered membrane domains rich in cholesterol and sphingolipids, near the slit diaphragm highlights the importance of lipid metabolism in podocyte health. Emerging research shows the importance of sphingolipid metabolism to podocyte health through structural and signaling roles. Dysregulation in sphingolipid metabolism has been shown to cause podocyte injury and drive glomerular disease progression. In this review, we discuss the structure and metabolism of sphingolipids, as well as their role in proper podocyte function and how alterations in sphingolipid metabolism contributes to podocyte injury and drives glomerular disease progression.
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Affiliation(s)
| | - Sandra Merscher
- Peggy and Harold Katz Family Drug Discovery Center, Miller School of Medicine, University of Miami, Miami, FL 33136, USA;
| | - Alessia Fornoni
- Peggy and Harold Katz Family Drug Discovery Center, Miller School of Medicine, University of Miami, Miami, FL 33136, USA;
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2
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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: 3] [Impact Index Per Article: 3.0] [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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3
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Günther A, Hose M, Abberger H, Schumacher F, Veith Y, Kleuser B, Matuschewski K, Lang KS, Gulbins E, Buer J, Westendorf A, Hansen W. The acid ceramidase/ceramide axis controls parasitemia in Plasmodium yoelii-infected mice by regulating erythropoiesis. eLife 2022; 11:77975. [PMID: 36094170 PMCID: PMC9499531 DOI: 10.7554/elife.77975] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/17/2022] [Accepted: 09/09/2022] [Indexed: 11/13/2022] Open
Abstract
Acid ceramidase (Ac) is part of the sphingolipid metabolism and responsible for the degradation of ceramide. As bioactive molecule, ceramide is involved in the regulation of many cellular processes. However, the impact of cell-intrinsic Ac activity and ceramide on the course of Plasmodium infection remains elusive. Here, we use Ac-deficient mice with ubiquitously increased ceramide levels to elucidate the role of endogenous Ac activity in a murine malaria model. Interestingly, ablation of Ac leads to alleviated parasitemia associated with decreased T cell responses in the early phase of Plasmodium yoelii infection. Mechanistically, we identified dysregulated erythropoiesis with reduced numbers of reticulocytes, the preferred host cells of P. yoelii, in Ac-deficient mice. Furthermore, we demonstrate that administration of the Ac inhibitor carmofur to wildtype mice has similar effects on P. yoelii infection and erythropoiesis. Notably, therapeutic carmofur treatment after manifestation of P. yoelii infection is efficient in reducing parasitemia. Hence, our results provide evidence for the involvement of Ac and ceramide in controlling P. yoelii infection by regulating red blood cell development.
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Affiliation(s)
- Anne Günther
- Institute of Medical Microbiology, University of Duisburg-Essen, Essen, Germany
| | - Matthias Hose
- Institute of Medical Microbiology, University of Duisburg-Essen, Essen, Germany
| | - Hanna Abberger
- Institute of Medical Microbiology, University of Duisburg-Essen, Essen, Germany
| | | | - Ylva Veith
- Institute of Biology, Humboldt-Universität zu Berlin, Berlin, Germany
| | - Burkhard Kleuser
- Institute of Pharmacy, Freie Universität Berlin, Berlin, Germany
| | - Kai Matuschewski
- Institute of Biology, Humboldt-Universität zu Berlin, Berlin, Germany
| | | | - Erich Gulbins
- Institute of Molecular Biology, University of Duisburg-Essen, Essen, Germany
| | - Jan Buer
- Institute of Medical Microbiology, University of Duisburg-Essen, Essen, Germany
| | - Astrid Westendorf
- Institute of Medical Microbiology, University of Duisburg-Essen, Duisburg, Germany
| | - Wiebke Hansen
- Institute of Medical Microbiology, University of Duisburg-Essen, Essen, Germany
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4
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Hawkins CC, Ali T, Ramanadham S, Hjelmeland AB. Sphingolipid Metabolism in Glioblastoma and Metastatic Brain Tumors: A Review of Sphingomyelinases and Sphingosine-1-Phosphate. Biomolecules 2020; 10:E1357. [PMID: 32977496 PMCID: PMC7598277 DOI: 10.3390/biom10101357] [Citation(s) in RCA: 25] [Impact Index Per Article: 6.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/31/2020] [Revised: 09/18/2020] [Accepted: 09/20/2020] [Indexed: 01/05/2023] Open
Abstract
Glioblastoma (GBM) is a primary malignant brain tumor with a dismal prognosis, partially due to our inability to completely remove and kill all GBM cells. Rapid tumor recurrence contributes to a median survival of only 15 months with the current standard of care which includes maximal surgical resection, radiation, and temozolomide (TMZ), a blood-brain barrier (BBB) penetrant chemotherapy. Radiation and TMZ cause sphingomyelinases (SMase) to hydrolyze sphingomyelins to generate ceramides, which induce apoptosis. However, cells can evade apoptosis by converting ceramides to sphingosine-1-phosphate (S1P). S1P has been implicated in a wide range of cancers including GBM. Upregulation of S1P has been linked to the proliferation and invasion of GBM and other cancers that display a propensity for brain metastasis. To mediate their biological effects, SMases and S1P modulate signaling via phospholipase C (PLC) and phospholipase D (PLD). In addition, both SMase and S1P may alter the integrity of the BBB leading to infiltration of tumor-promoting immune populations. SMase activity has been associated with tumor evasion of the immune system, while S1P creates a gradient for trafficking of innate and adaptive immune cells. This review will explore the role of sphingolipid metabolism and pharmacological interventions in GBM and metastatic brain tumors with a focus on SMase and S1P.
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Affiliation(s)
- Cyntanna C. Hawkins
- Department of Cell, Developmental, and Integrative Biology, University of Birmingham at Alabama, Birmingham, AL 35233, USA; (C.C.H.); (S.R.)
| | - Tomader Ali
- Research Department, Imperial College London Diabetes Centre, Abu Dhabi P.O. Box 48338, UAE;
| | - Sasanka Ramanadham
- Department of Cell, Developmental, and Integrative Biology, University of Birmingham at Alabama, Birmingham, AL 35233, USA; (C.C.H.); (S.R.)
- Comprehensive Diabetes Center, University of Birmingham at Alabama, Birmingham, AL 35294, USA
| | - Anita B. Hjelmeland
- Department of Cell, Developmental, and Integrative Biology, University of Birmingham at Alabama, Birmingham, AL 35233, USA; (C.C.H.); (S.R.)
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5
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Casasampere M, Bielsa N, Riba D, Bassas L, Xu R, Mao C, Fabriàs G, Abad JL, Delgado A, Casas J. New fluorogenic probes for neutral and alkaline ceramidases. J Lipid Res 2019; 60:1174-1181. [PMID: 30926626 DOI: 10.1194/jlr.d092759] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/29/2019] [Revised: 03/27/2019] [Indexed: 12/20/2022] Open
Abstract
New fluorogenic ceramidase substrates derived from the N-acyl modification of our previously reported probes (RBM14) are reported. While none of the new probes were superior to the known RBM14C12 as acid ceramidase substrates, the corresponding nervonic acid amide (RBM14C24:1) is an efficient and selective substrate for the recombinant human neutral ceramidase, both in cell lysates and in intact cells. A second generation of substrates, incorporating the natural 2-(N-acylamino)-1,3-diol-4-ene framework (compounds RBM15) is also reported. Among them, the corresponding fatty acyl amides with an unsaturated N-acyl chain can be used as substrates to determine alkaline ceramidase (ACER)1 and ACER2 activities. In particular, compound RBM15C18:1 has emerged as the best fluorogenic probe reported so far to measure ACER1 and ACER2 activities in a 96-well plate format.
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Affiliation(s)
- Mireia Casasampere
- Spanish National Research Council (CSIC), Institute for Advanced Chemistry of Catalonia (IQAC-CSIC), Department of Biological Chemistry, Research Unit on Bioactive Molecules (RUBAM), 08034 Barcelona, Spain.,Faculty of Pharmacy and Food Sciences Department of Pharmacology, Toxicology, and Medicinal Chemistry, Unit of Pharmaceutical Chemistry (Associated Unit to CSIC), University of Barcelona, 08028 Barcelona, Spain
| | - Núria Bielsa
- Spanish National Research Council (CSIC), Institute for Advanced Chemistry of Catalonia (IQAC-CSIC), Department of Biological Chemistry, Research Unit on Bioactive Molecules (RUBAM), 08034 Barcelona, Spain.,Faculty of Pharmacy and Food Sciences Department of Pharmacology, Toxicology, and Medicinal Chemistry, Unit of Pharmaceutical Chemistry (Associated Unit to CSIC), University of Barcelona, 08028 Barcelona, Spain
| | - Daniel Riba
- Spanish National Research Council (CSIC), Institute for Advanced Chemistry of Catalonia (IQAC-CSIC), Department of Biological Chemistry, Research Unit on Bioactive Molecules (RUBAM), 08034 Barcelona, Spain
| | - Laura Bassas
- Spanish National Research Council (CSIC), Institute for Advanced Chemistry of Catalonia (IQAC-CSIC), Department of Biological Chemistry, Research Unit on Bioactive Molecules (RUBAM), 08034 Barcelona, Spain
| | - Ruijuan Xu
- Department of Medicine State University of New York at Stony Brook, Stony Brook, NY 11794-8155
| | - Cungui Mao
- Department of Medicine State University of New York at Stony Brook, Stony Brook, NY 11794-8155
| | - Gemma Fabriàs
- Spanish National Research Council (CSIC), Institute for Advanced Chemistry of Catalonia (IQAC-CSIC), Department of Biological Chemistry, Research Unit on Bioactive Molecules (RUBAM), 08034 Barcelona, Spain.,Centro de Investigación Biomédica en Red (CIBEREHD), 28029 Madrid, Spain
| | - José-Luis Abad
- Spanish National Research Council (CSIC), Institute for Advanced Chemistry of Catalonia (IQAC-CSIC), Department of Biological Chemistry, Research Unit on Bioactive Molecules (RUBAM), 08034 Barcelona, Spain
| | - Antonio Delgado
- Spanish National Research Council (CSIC), Institute for Advanced Chemistry of Catalonia (IQAC-CSIC), Department of Biological Chemistry, Research Unit on Bioactive Molecules (RUBAM), 08034 Barcelona, Spain .,Faculty of Pharmacy and Food Sciences Department of Pharmacology, Toxicology, and Medicinal Chemistry, Unit of Pharmaceutical Chemistry (Associated Unit to CSIC), University of Barcelona, 08028 Barcelona, Spain
| | - Josefina Casas
- Spanish National Research Council (CSIC), Institute for Advanced Chemistry of Catalonia (IQAC-CSIC), Department of Biological Chemistry, Research Unit on Bioactive Molecules (RUBAM), 08034 Barcelona, Spain .,Centro de Investigación Biomédica en Red (CIBEREHD), 28029 Madrid, Spain
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6
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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: 78] [Impact Index Per Article: 13.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [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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7
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Cozma C, Iurașcu MI, Eichler S, Hovakimyan M, Brandau O, Zielke S, Böttcher T, Giese AK, Lukas J, Rolfs A. C26-Ceramide as highly sensitive biomarker for the diagnosis of Farber Disease. Sci Rep 2017; 7:6149. [PMID: 28733637 PMCID: PMC5522391 DOI: 10.1038/s41598-017-06604-2] [Citation(s) in RCA: 24] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/24/2016] [Accepted: 06/15/2017] [Indexed: 12/31/2022] Open
Abstract
Farber disease (FD) is a rare autosomal recessive disease caused by mutations in the acid ceramidase gene (ASAH1). Low ceramidase activity results in the accumulation of fatty substances, mainly ceramides. Hallmark symptoms at clinical level are periarticular nodules, lipogranulomas, swollen and painful joints and a hoarse voice. FD phenotypes are heterogeneous varying from mild to very severe cases, with the patients not surviving past their first year of life. The diagnostic aspects of FD are poorly developed due to the rarity of the disease. In the present study, the screening for ceramides and related molecules was performed in Farber affected patients (n = 10), carriers (n = 11) and control individuals (n = 192). This study has the highest number of enrolled Farber patients and carriers reported to present. Liquid chromatography multiple reaction mass spectrometry (LC/MRM-MS) studies revealed that the ceramide C26:0 and especially its isoform 1 is a highly sensitive and specific biomarker for FD (p < 0.0001). The new biomarker can be determined directly in the dried blood spot extracts with low sample consumption. This allows for easy sample preparation, high reproducibility and use in high throughput screenings.
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Affiliation(s)
- Claudia Cozma
- Centogene AG, Schillingallee 68, 18057, Rostock, Germany.
| | | | | | | | - Oliver Brandau
- Centogene AG, Schillingallee 68, 18057, Rostock, Germany
| | - Susanne Zielke
- Albrecht-Kossel-Institute for Neurodegeneration, Rostock University Medical Centre, Gehlsheimerstraße 20, 18147, Rostock, Germany
| | - Tobias Böttcher
- Albrecht-Kossel-Institute for Neurodegeneration, Rostock University Medical Centre, Gehlsheimerstraße 20, 18147, Rostock, Germany
| | - Anne-Katrin Giese
- Albrecht-Kossel-Institute for Neurodegeneration, Rostock University Medical Centre, Gehlsheimerstraße 20, 18147, Rostock, Germany
| | - Jan Lukas
- Albrecht-Kossel-Institute for Neurodegeneration, Rostock University Medical Centre, Gehlsheimerstraße 20, 18147, Rostock, Germany
| | - Arndt Rolfs
- Centogene AG, Schillingallee 68, 18057, Rostock, Germany.,Albrecht-Kossel-Institute for Neurodegeneration, Rostock University Medical Centre, Gehlsheimerstraße 20, 18147, Rostock, Germany
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8
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Ortega JA, Arencibia JM, La Sala G, Borgogno M, Bauer I, Bono L, Braccia C, Armirotti A, Girotto S, Ganesan A, De Vivo M. Pharmacophore Identification and Scaffold Exploration to Discover Novel, Potent, and Chemically Stable Inhibitors of Acid Ceramidase in Melanoma Cells. J Med Chem 2017; 60:5800-5815. [PMID: 28603987 DOI: 10.1021/acs.jmedchem.7b00472] [Citation(s) in RCA: 14] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/20/2022]
Abstract
Acid ceramidase (AC) hydrolyzes ceramides, which are central lipid messengers for metabolism and signaling of sphingolipids. A growing body of evidence links deregulation of sphingolipids to several diseases, including cancer. Indeed, AC expression is abnormally high in melanoma cells. AC inhibition may thus be key to treating malignant melanoma. Here, we have used a systematic scaffold exploration to design a general pharmacophore for AC inhibition. This pharmacophore comprises a 6 + 5 fused ring heterocycle linked to an aliphatic substituent via a urea moiety. We have thus identified the novel benzimidazole derivatives 10, 21, 27, and 30, which are highly potent AC inhibitors. Their chemical and metabolic stabilities are comparable or superior to those of previously reported AC inhibitors. Moreover, they are potent against endogenous AC in intact melanoma cells. These novel inhibitors merit further characterization and can serve as a promising starting point for the discovery of new antimelanoma therapeutics.
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Affiliation(s)
- Jose Antonio Ortega
- Laboratory of Molecular Modeling & Drug Discovery, Istituto Italiano di Tecnologia , Via Morego 30, 16163 Genoa, Italy
| | - Jose M Arencibia
- Laboratory of Molecular Modeling & Drug Discovery, Istituto Italiano di Tecnologia , Via Morego 30, 16163 Genoa, Italy
| | - Giuseppina La Sala
- Laboratory of Molecular Modeling & Drug Discovery, Istituto Italiano di Tecnologia , Via Morego 30, 16163 Genoa, Italy
| | - Marco Borgogno
- Laboratory of Molecular Modeling & Drug Discovery, Istituto Italiano di Tecnologia , Via Morego 30, 16163 Genoa, Italy
| | - Inga Bauer
- CompuNet, Istituto Italiano di Tecnologia , Via Morego 30, 16163 Genoa, Italy
| | - Luca Bono
- D3-PharmaChemistry, Istituto Italiano di Tecnologia , Via Morego 30, 16163 Genoa, Italy
| | - Clarissa Braccia
- D3-PharmaChemistry, Istituto Italiano di Tecnologia , Via Morego 30, 16163 Genoa, Italy
| | - Andrea Armirotti
- D3-PharmaChemistry, Istituto Italiano di Tecnologia , Via Morego 30, 16163 Genoa, Italy
| | - Stefania Girotto
- CompuNet, Istituto Italiano di Tecnologia , Via Morego 30, 16163 Genoa, Italy
| | - Anand Ganesan
- Department of Dermatology and Biological Chemistry, University of California , 202 Sprague Hall, 92697-2400 Irvine, United States
| | - Marco De Vivo
- Laboratory of Molecular Modeling & Drug Discovery, Istituto Italiano di Tecnologia , Via Morego 30, 16163 Genoa, Italy.,IAS-5/INM-9 Computational Biomedicine Forschungszentrum Jülich , Wilhelm-Johnen-Straße, 52428 Jülich, Germany
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9
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Wang K, Xu R, Schrandt J, Shah P, Gong YZ, Preston C, Wang L, Yi JK, Lin CL, Sun W, Spyropoulos DD, Rhee S, Li M, Zhou J, Ge S, Zhang G, Snider AJ, Hannun YA, Obeid LM, Mao C. Alkaline Ceramidase 3 Deficiency Results in Purkinje Cell Degeneration and Cerebellar Ataxia Due to Dyshomeostasis of Sphingolipids in the Brain. PLoS Genet 2015; 11:e1005591. [PMID: 26474409 PMCID: PMC4608763 DOI: 10.1371/journal.pgen.1005591] [Citation(s) in RCA: 42] [Impact Index Per Article: 4.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/19/2015] [Accepted: 09/18/2015] [Indexed: 01/21/2023] Open
Abstract
Dyshomeostasis of both ceramides and sphingosine-1-phosphate (S1P) in the brain has been implicated in aging-associated neurodegenerative disorders in humans. However, mechanisms that maintain the homeostasis of these bioactive sphingolipids in the brain remain unclear. Mouse alkaline ceramidase 3 (Acer3), which preferentially catalyzes the hydrolysis of C18:1-ceramide, a major unsaturated long-chain ceramide species in the brain, is upregulated with age in the mouse brain. Acer3 knockout causes an age-dependent accumulation of various ceramides and C18:1-monohexosylceramide and abolishes the age-related increase in the levels of sphingosine and S1P in the brain; thereby resulting in Purkinje cell degeneration in the cerebellum and deficits in motor coordination and balance. Our results indicate that Acer3 plays critically protective roles in controlling the homeostasis of various sphingolipids, including ceramides, sphingosine, S1P, and certain complex sphingolipids in the brain and protects Purkinje cells from premature degeneration. Bioactive sphingolipids, such as ceramides and sphingosine-1-phosphates, have been implicated in neurodegenerative diseases. However, it remains unclear as to how the homeostasis of these bioactive lipids is sustained. Alkaline ceramidase 3 (ACER3) catalyzes the hydrolysis of saturated long-chain ceramides (C18:1-ceramide and C20:1-ceramide) to generate sphingosine (SPH), which is phosphorylated to form sphingosine-1-phosphate (S1P). In this study we found that Acer3 is upregulated with age in the mouse brain and blocking Acer3 upregulation elevates the levels of ceramides while reducing S1P levels in the brain, thereby resulting in Purkinje cell loss and cerebellar ataxia. This study not only offers novel insights into the role for the homeostasis of ceramides and their metabolites in regulating normal aging of the cerebellum, but also provides a useful genetic tool to dissect the mechanism by which an aberrant accumulation of ceramides results in age-related neurological disorders.
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Affiliation(s)
- Kai Wang
- Department of Medicine, Stony Brook University, Stony Brook, New York, United States of America
- Stony Brook Cancer Center, Stony Brook, New York, United States of America
- Department of Hepatobiliary Surgery, Nanfang Hospital, Southern Medical University, Guangzhou, China
| | - Ruijuan Xu
- Department of Medicine, Stony Brook University, Stony Brook, New York, United States of America
- Stony Brook Cancer Center, Stony Brook, New York, United States of America
| | - Jennifer Schrandt
- Department of Medicine, Stony Brook University, Stony Brook, New York, United States of America
- Stony Brook Cancer Center, Stony Brook, New York, United States of America
| | - Prithvi Shah
- Division of Rehabilitation Sciences, Department of Physical Therapy, School of Health Technology and Management, Stony Brook University, Stony Brook, New York, United States of America
- Department of Neurobiology and Behavior, Stony Brook University, Stony Brook, New York, United States of America
| | - Yong Z. Gong
- Medical University of South Carolina, Charleston, South Carolina, United States of America
| | - Chet Preston
- Division of Rehabilitation Sciences, Department of Physical Therapy, School of Health Technology and Management, Stony Brook University, Stony Brook, New York, United States of America
| | - Louis Wang
- Division of Rehabilitation Sciences, Department of Physical Therapy, School of Health Technology and Management, Stony Brook University, Stony Brook, New York, United States of America
| | - Jae Kyo Yi
- Department of Medicine, Stony Brook University, Stony Brook, New York, United States of America
- Stony Brook Cancer Center, Stony Brook, New York, United States of America
| | - Chih-Li Lin
- Department of Medicine, Stony Brook University, Stony Brook, New York, United States of America
- Stony Brook Cancer Center, Stony Brook, New York, United States of America
| | - Wei Sun
- Medical University of South Carolina, Charleston, South Carolina, United States of America
| | - Demetri D. Spyropoulos
- Medical University of South Carolina, Charleston, South Carolina, United States of America
| | - Soyoung Rhee
- Medical University of South Carolina, Charleston, South Carolina, United States of America
| | - Mingsong Li
- Department of Gastroenterology, Nanfang Hospital, Southern Medical University, Guangzhou, China
| | - Jie Zhou
- Department of Hepatobiliary Surgery, Nanfang Hospital, Southern Medical University, Guangzhou, China
| | - Shaoyu Ge
- Medical University of South Carolina, Charleston, South Carolina, United States of America
| | - Guofeng Zhang
- Biomedical Engineering and Physical Science Shared Resource, National Institute of Biomedical Imaging and Bioengineering, National Institute of Health, Bethesda, Maryland, United States of America
| | - Ashley J. Snider
- Department of Medicine, Stony Brook University, Stony Brook, New York, United States of America
- Stony Brook Cancer Center, Stony Brook, New York, United States of America
- Northport Veterans Affairs Medical Center, Northport, New York, United States of America
| | - Yusuf A. Hannun
- Department of Medicine, Stony Brook University, Stony Brook, New York, United States of America
- Stony Brook Cancer Center, Stony Brook, New York, United States of America
| | - Lina M. Obeid
- Department of Medicine, Stony Brook University, Stony Brook, New York, United States of America
- Stony Brook Cancer Center, Stony Brook, New York, United States of America
- Northport Veterans Affairs Medical Center, Northport, New York, United States of America
| | - Cungui Mao
- Department of Medicine, Stony Brook University, Stony Brook, New York, United States of America
- Stony Brook Cancer Center, Stony Brook, New York, United States of America
- * E-mail:
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10
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Abstract
The topic of ceramidases has experienced an enormous boost during the last few years. Ceramidases catalyze the degradation of ceramide to sphingosine and fatty acids. Ceramide is not only the central hub of sphingolipid biosynthesis and degradation, it is also a key molecule in sphingolipid signaling, promoting differentiation or apoptosis. Acid ceramidase inhibition sensitizes certain types of cancer to chemo- and radio-therapy and this is suggestive of a role of acid ceramidase inhibitors as chemo-sensitizers which can act synergistically with chemo-therapeutic drugs. In this review, we summarize the development of ceramide analogues as first-generation ceramidase inhibitors together with data on their activity in cells and disease models. Furthermore, we describe the recent developments that have led to highly potent second-generation ceramidase inhibitors that act at nanomolar concentrations. In the third part, various assays of ceramidases are described and their relevance for accurately measuring ceramidase activities and for the development of novel inhibitors is highlighted. Besides potential clinical implications, the recent improvements in ceramidase inhibition and assaying may help to better understand the mechanisms of ceramide biology.
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Affiliation(s)
- Essa M Saied
- Humboldt Universität zu Berlin, Institute for Chemistry, Berlin, Germany; Suez Canal University, Chemistry Department, Faculty of Science, Ismailia, Egypt
| | - Christoph Arenz
- Humboldt Universität zu Berlin, Institute for Chemistry, Berlin, Germany.
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11
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Mizutani N, Inoue M, Omori Y, Ito H, Tamiya-Koizumi K, Takagi A, Kojima T, Nakamura M, Iwaki S, Nakatochi M, Suzuki M, Nozawa Y, Murate T. Increased acid ceramidase expression depends on upregulation of androgen-dependent deubiquitinases, USP2, in a human prostate cancer cell line, LNCaP. J Biochem 2015; 158:309-19. [PMID: 25888580 DOI: 10.1093/jb/mvv039] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/27/2015] [Accepted: 03/25/2015] [Indexed: 01/03/2023] Open
Abstract
Acid ceramidase (ACDase) metabolizes ceramide to sphingosine, leading to sphingosine 1-phosphate production. Reportedly, ACDase has been upregulated in prostate cancer. However, its regulatory mechanism remains unclear. LNCaP (androgen-sensitive prostate cancer cell line) but not PC3 and DU-145, (androgen-unresponsive cell lines) exhibited the highest ACDase protein. Among three cell lines, ASAH1 mRNA level was not correlated with ACDase protein expression, and the 5'-promoter activity did not show androgen dependency, suggesting the post-transcriptional regulation of ACDase in LNCaP cells. Based on these results, LNCaP was analysed further. Casodex, androgen receptor antagonist, and charcoal-stripped FCS (CS-FCS) decreased ACDase protein and activity, whereas dihydrotestosterone in CS-FCS culture increased ACDase protein and enzyme activity. MG132, a proteasome inhibitor, prevented the decrease of ACDase protein when cultured in CS-FCS, suggesting the involvement of ubiquitin/proteasome system. Reportedly, USP2, a deubiquitinase, plays an important role in LNCaP cells. USP2 siRNA decreased ACDase protein, whereas USP2 overexpression increased ACDase protein of LNCaP cells. However, SKP2, an ubiquitin E3 ligase known to be active in prostate cancer, did not affect androgen-dependent ACDase expression in LNCaP cells. Thus, ACDase regulation by androgen in androgen-sensitive LNCaP cells is mainly due to its prolonged protein half-life by androgen-stimulated USP2 expression.
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Affiliation(s)
- Naoki Mizutani
- Department of Pathophysiological Laboratory Science, Nagoya University Graduate School of Medicine, Nagoya 461-8673
| | - Minami Inoue
- Department of Pathophysiological Laboratory Science, Nagoya University Graduate School of Medicine, Nagoya 461-8673
| | - Yukari Omori
- Department of Pathophysiological Laboratory Science, Nagoya University Graduate School of Medicine, Nagoya 461-8673
| | - Hiromi Ito
- Department of Pathophysiological Laboratory Science, Nagoya University Graduate School of Medicine, Nagoya 461-8673
| | - Keiko Tamiya-Koizumi
- Department of Pathophysiological Laboratory Science, Nagoya University Graduate School of Medicine, Nagoya 461-8673
| | - Akira Takagi
- Department of Pathophysiological Laboratory Science, Nagoya University Graduate School of Medicine, Nagoya 461-8673
| | - Tetsuhito Kojima
- Department of Pathophysiological Laboratory Science, Nagoya University Graduate School of Medicine, Nagoya 461-8673
| | - Mitsuhiro Nakamura
- Department of Drug Information, Gifu Pharmaceutical University, Gifu 501-1196
| | - Soichiro Iwaki
- Department of Molecular and Cellular Pathophysiology and Therapeutics, Graduate School of Pharmaceutical Science, Nagoya City University, Nagoya 467-8603
| | - Masahiro Nakatochi
- Bioinformatics Section, Center for Advanced Medicine and Clinical Research, Nagoya University Hospital, Nagoya 466-8550
| | - Motoshi Suzuki
- Division of Molecular Carcinogenesis, Nagoya University Graduate School of Medicine, Nagoya 466-8560; and
| | - Yoshinori Nozawa
- Department of Food and Health Science, Tokai Gakuin University, Kakamigahara 504-8511, Japan
| | - Takashi Murate
- Department of Pathophysiological Laboratory Science, Nagoya University Graduate School of Medicine, Nagoya 461-8673;
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12
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Carroll B, Donaldson JC, Obeid L. Sphingolipids in the DNA damage response. Adv Biol Regul 2014; 58:38-52. [PMID: 25434743 DOI: 10.1016/j.jbior.2014.11.001] [Citation(s) in RCA: 42] [Impact Index Per Article: 4.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/02/2014] [Revised: 11/06/2014] [Accepted: 11/07/2014] [Indexed: 12/16/2022]
Abstract
Recently, sphingolipid metabolizing enzymes have emerged as important targets of many chemotherapeutics and DNA damaging agents and therefore play significant roles in mediating the physiological response of the cell to DNA damage. In this review we will highlight points of connection between the DNA damage response (DDR) and sphingolipid metabolism; specifically how certain sphingolipid enzymes are regulated in response to DNA damage and how the bioactive lipids produced by these enzymes affect cell fate.
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Affiliation(s)
- Brittany Carroll
- Department of Medicine, Stony Brook University, Stony Brook, NY 11794, USA; Stony Brook Cancer Center, Stony Brook University, Stony Brook, NY 11794, USA
| | - Jane Catalina Donaldson
- Department of Medicine, Stony Brook University, Stony Brook, NY 11794, USA; Stony Brook Cancer Center, Stony Brook University, Stony Brook, NY 11794, USA
| | - Lina Obeid
- Northport VA Medical Center, Northport, NY 11768, USA; Department of Medicine, Stony Brook University, Stony Brook, NY 11794, USA; Stony Brook Cancer Center, Stony Brook University, Stony Brook, NY 11794, USA.
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13
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Signaling and regulatory functions of bioactive sphingolipids as therapeutic targets in multiple sclerosis. Neurochem Res 2012; 37:1154-69. [PMID: 22451227 DOI: 10.1007/s11064-012-0728-y] [Citation(s) in RCA: 24] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/22/2011] [Revised: 01/04/2012] [Accepted: 02/10/2012] [Indexed: 12/21/2022]
Abstract
Spingolipids (SLs) are an important component of central nervous system (CNS) myelin sheaths and affect the viability of brain cells (oligodendrocytes, neurons and astrocytes) that is determined by signaling mediated by bioactive sphingoids (lyso-SLs). Recent studies indicate that two lipids, ceramide and sphingosine 1-phosphate (S1P), are particularly involved in many human diseases including the autoimmune inflammatory demyelination of multiple sclerosis (MS). In this review we: (1) Discuss possible sources of ceramide in CNS; (2) Summarize the features of the metabolism of S1P and its downstream signaling through G-protein-coupled receptors; (3) Link perturbations in bioactive SLs metabolism to MS neurodegeneration and (4) Compile ceramide and S1P relationships to this process. In addition, we described recent preclinical and clinical trials of therapies targeting S1P signaling, including 2-amino-2-propane-1,3-diol hydrochloride (FTY720, fingolimod) as well as proposed intervention to specify critical SL levels that tilt balances of apoptotic/active ceramide versus anti-apoptotic/inactive dihydroceramide that may offer a novel and important therapeutic approach to MS.
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14
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Lucki NC, Bandyopadhyay S, Wang E, Merrill AH, Sewer MB. Acid ceramidase (ASAH1) is a global regulator of steroidogenic capacity and adrenocortical gene expression. Mol Endocrinol 2012; 26:228-43. [PMID: 22261821 PMCID: PMC3275158 DOI: 10.1210/me.2011-1150] [Citation(s) in RCA: 30] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/21/2011] [Accepted: 12/14/2011] [Indexed: 11/19/2022] Open
Abstract
In H295R human adrenocortical cells, ACTH rapidly activates ceramide (Cer) and sphingosine (SPH) turnover with a concomitant increase in SPH-1-phosphate secretion. These bioactive lipids modulate adrenocortical steroidogenesis, primarily by acting as second messengers in the protein kinase A/cAMP-dependent pathway. Acid ceramidase (ASAH1) directly regulates the intracellular balance of Cer, SPH, and SPH-1-phosphate by catalyzing the hydrolysis of Cer into SPH. ACTH/cAMP signaling stimulates ASAH1 transcription and activity, supporting a role for this enzyme in glucocorticoid production. Here, the role of ASAH1 in regulating steroidogenic capacity was examined using a tetracycline-inducible ASAH1 short hairpin RNA H295R human adrenocortical stable cell line. We show that ASAH1 suppression increases the transcription of multiple steroidogenic genes, including Cytochrome P450 monooxygenase (CYP)17A1, CYP11B1/2, CYP21A2, steroidogenic acute regulatory protein, hormone-sensitive lipase, 18-kDa translocator protein, and the melanocortin-2 receptor. Induced gene expression positively correlated with enhanced histone H3 acetylation at target promoters. Repression of ASAH1 expression also induced the expression of members of the nuclear receptor nuclear receptor subfamily 4 (NR4A) family while concomitantly suppressing the expression of dosage-sensitive sex reversal, adrenal hypoplasia critical region, on chromosome X, gene 1. ASAH1 knockdown altered the expression of genes involved in sphingolipid metabolism and changed the cellular amounts of distinct sphingolipid species. Finally, ASAH1 silencing increased basal and cAMP-dependent cortisol and dehydroepiandrosterone secretion, establishing ASAH1 as a pivotal regulator of steroidogenic capacity in the human adrenal cortex.
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Affiliation(s)
- Natasha C Lucki
- School of Biology, Georgia Institute of Technology, Atlanta, Georgia 30332-0230, USA
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15
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Bedia C, Camacho L, Abad JL, Fabriàs G, Levade T. A simple fluorogenic method for determination of acid ceramidase activity and diagnosis of Farber disease. J Lipid Res 2010; 51:3542-7. [PMID: 20871013 DOI: 10.1194/jlr.d010033] [Citation(s) in RCA: 50] [Impact Index Per Article: 3.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022] Open
Abstract
Acid ceramidase (aCDase) is one of several enzymes responsible for ceramide degradation within mammalian cells. As such, aCDase regulates the intracellular levels of the bioactive lipid ceramide. An inherited deficiency of aCDase activity results in Farber disease (FD), also called lipogranulomatosis, which is characterized by ceramide accumulation in the tissues of patients. Diagnosis of FD is confirmed by demonstration of a deficient aCDase activity and the subsequent storage of ceramide. Existing methods include extremely complex assays, many of them using radiolabeled compounds. Therefore, the aCDase assay and the in vitro enzymatic diagnosis of FD are still performed in only a very limited number of specialized laboratories. Here, the new fluorogenic substrate Rbm14-12 was synthesized and characterized as a new tool to determine aCDase activity. The resulting optimized assay was performed in 96-well plates, and different fibroblast and lymphoid cell lines derived from FD patients and controls were tested to measure aCDase activity. As a result, the activity in cells of FD patients was found to be very low or even null. This new fluorogenic method offers a very easy and rapid way for specific and accurate determination of aCDase activity and, consequently, for diagnosis of FD.
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16
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Mao Z, Sun W, Xu R, Novgorodov S, Szulc ZM, Bielawski J, Obeid LM, Mao C. Alkaline ceramidase 2 (ACER2) and its product dihydrosphingosine mediate the cytotoxicity of N-(4-hydroxyphenyl)retinamide in tumor cells. J Biol Chem 2010; 285:29078-90. [PMID: 20628055 PMCID: PMC2937939 DOI: 10.1074/jbc.m110.105296] [Citation(s) in RCA: 42] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/18/2010] [Revised: 07/09/2010] [Indexed: 11/06/2022] Open
Abstract
Increased generation of dihydrosphingosine (DHS), a bioactive sphingolipid, has been implicated in the cytotoxicity of the synthetic retinoid N-(4-hydroxyphenyl)retinamide (4-HPR) in tumor cells. However, how 4-HPR increases DHS remains unclear. Here we demonstrate that 4-HPR increases the expression of ACER2, which catalyzes the hydrolysis of dihydroceramides to generate DHS, and that ACER2 up-regulation plays a key role in mediating the 4-HPR-induced generation of DHS as well as the cytotoxicity of 4-HPR in tumor cells. Treatment with 4-HPR induced the accumulation of dihydroceramides (DHCs) in tumor cells by inhibiting dihydroceramide desaturase (DES) activity, which catalyzes the conversion of DHCs to ceramides. Treatment with 4-HPR also increased ACER2 expression through a retinoic acid receptor-independent and caspase-dependent manner. Overexpression of ACER2 augmented the 4-HPR-induced generation of DHS as well as 4-HPR cytotoxicity, and 4-HPR-induced death in tumor cells, whereas knocking down ACER2 had the opposite effects. ACER2 overexpression, along with treatment with GT11, another DES inhibitor, markedly increased cellular DHS, leading to tumor cell death, whereas ACER2 overexpression or GT11 treatment alone failed to do so, suggesting that both ACER2 up-regulation and DES inhibition are necessary and sufficient to mediate 4-HPR-induced DHS accumulation, cytotoxicity, and death in tumor cells. Taken together, these results suggest that up-regulation of the ACER2/DHS pathway mediates the cytotoxicity of 4-HPR in tumor cells and that up-regulating or activating ACER2 may improve the anti-cancer activity of 4-HRR and other DHC-inducing agents.
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Affiliation(s)
| | - Wei Sun
- From the Department of Medicine and
| | | | | | - Zdzislaw M. Szulc
- the Department of Biochemistry and Molecular Biology, Medical University of South Carolina and
| | - Jacek Bielawski
- the Department of Biochemistry and Molecular Biology, Medical University of South Carolina and
| | - Lina M. Obeid
- From the Department of Medicine and
- the Department of Biochemistry and Molecular Biology, Medical University of South Carolina and
- the Ralph H. Johnson Veterans Administration Hospital, Charleston, South Carolina 29425
| | - Cungui Mao
- From the Department of Medicine and
- the Department of Biochemistry and Molecular Biology, Medical University of South Carolina and
- the Ralph H. Johnson Veterans Administration Hospital, Charleston, South Carolina 29425
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17
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Xu R, Sun W, Jin J, Obeid LM, Mao C. Role of alkaline ceramidases in the generation of sphingosine and its phosphate in erythrocytes. FASEB J 2010; 24:2507-15. [PMID: 20207939 DOI: 10.1096/fj.09-153635] [Citation(s) in RCA: 37] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/09/2023]
Abstract
Plasma sphingosine-1-phosphate (S1P) has been suggested to mainly originate from erythrocytes; however, within the erythrocyte, how sphingosine (SPH) generation--the precursor to S1P--is controlled is unknown. SPH is only generated from the hydrolysis of ceramides via ceramidases. Five human ceramidases have been identified: 1 acid, 1 neutral, and 3 alkaline ceramidases (ACER1, ACER2, and ACER3). Here, we demonstrate that only alkaline ceramidase activity is expressed in erythrocytes and that it is instrumental for SPH generation. Erythrocytes have alkaline but not acid or neutral ceramidase activity on D-e-C(18:1)-ceramide, a common substrate of ceramidases. Not only alkaline ceramidase activity but also the generation of SPH and S1P are increased during erythroid differentiation in K562 erythroleukemic cells. Such SPH and S1P increases were inhibited by the alkaline ceramidase inhibitor D-e-MAPP, suggesting that alkaline ceramidases have a role in the generation of SPH and S1P in erythroid cells. Alkaline ceramidase activity is highly expressed in mouse erythrocytes, and intravenous administration of D-e-MAPP decreased both SPH and S1P in erythrocytes and plasma. Collectively, these results suggest that alkaline ceramidase activity is important for the generation of SPH, the S1P precursor in erythrocytes.
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Affiliation(s)
- Ruijuan Xu
- Department of Medicine, Medical University of South Carolina, Charleston, South Carolina, USA
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18
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Gangoiti P, Camacho L, Arana L, Ouro A, Granado MH, Brizuela L, Casas J, Fabriás G, Abad JL, Delgado A, Gómez-Muñoz A. Control of metabolism and signaling of simple bioactive sphingolipids: Implications in disease. Prog Lipid Res 2010; 49:316-34. [PMID: 20193711 DOI: 10.1016/j.plipres.2010.02.004] [Citation(s) in RCA: 108] [Impact Index Per Article: 7.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/15/2010] [Revised: 02/18/2010] [Accepted: 02/22/2010] [Indexed: 01/05/2023]
Abstract
Simple bioactive sphingolipids include ceramide, sphingosine and their phosphorylated forms sphingosine 1-phosphate and ceramide 1-phosphate. These molecules are crucial regulators of cell functions. In particular, they play important roles in the regulation of angiogenesis, apoptosis, cell proliferation, differentiation, migration, and inflammation. Decoding the mechanisms by which these cellular functions are regulated requires detailed understanding of the signaling pathways that are implicated in these processes. Most importantly, the development of inhibitors of the enzymes involved in their metabolism may be crucial for establishing new therapeutic strategies for treatment of disease.
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Affiliation(s)
- Patricia Gangoiti
- Department of Biochemistry and Molecular Biology, Faculty of Science and Technology, University of the Basque Country (UPV/EHU), Bilbao, Spain
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19
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Hu W, Xu R, Sun W, Szulc ZM, Bielawski J, Obeid LM, Mao C. Alkaline ceramidase 3 (ACER3) hydrolyzes unsaturated long-chain ceramides, and its down-regulation inhibits both cell proliferation and apoptosis. J Biol Chem 2010; 285:7964-76. [PMID: 20068046 DOI: 10.1074/jbc.m109.063586] [Citation(s) in RCA: 70] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/02/2023] Open
Abstract
Ceramides with different fatty acyl chains may vary in their physiological or pathological roles; however, it remains unclear how cellular levels of individual ceramide species are regulated. Here, we demonstrate that our previously cloned human alkaline ceramidase 3 (ACER3) specifically controls the hydrolysis of ceramides carrying unsaturated long acyl chains, unsaturated long-chain (ULC) ceramides. In vitro, ACER3 only hydrolyzed C(18:1)-, C(20:1)-, C(20:4)-ceramides, dihydroceramides, and phytoceramides. In cells, ACER3 overexpression decreased C(18:1)- and C(20:1)-ceramides and dihydroceramides, whereas ACER3 knockdown by RNA interference had the opposite effect, suggesting that ACER3 controls the catabolism of ULC ceramides and dihydroceramides. ACER3 knockdown inhibited cell proliferation and up-regulated the cyclin-dependent kinase inhibitor p21(CIP1/WAF1). Blocking p21(CIP1/WAF1) up-regulation attenuated the inhibitory effect of ACER3 knockdown on cell proliferation, suggesting that ACER3 knockdown inhibits cell proliferation because of p21(CIP1/WAF1) up-regulation. ACER3 knockdown inhibited cell apoptosis in response to serum deprivation. ACER3 knockdown up-regulated the expression of the alkaline ceramidase 2 (ACER2), and the ACER2 up-regulation decreased non-ULC ceramide species while increasing both sphingosine and its phosphate. Collectively, these data suggest that ACER3 catalyzes the hydrolysis of ULC ceramides and dihydroceramides and that ACER3 coordinates with ACER2 to regulate cell proliferation and survival.
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Affiliation(s)
- Wei Hu
- Departments of Medicine, Medical University of South Carolina, Charleston, South Carolina 29425, USA
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20
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Gault CR, Obeid LM, Hannun YA. An overview of sphingolipid metabolism: from synthesis to breakdown. ADVANCES IN EXPERIMENTAL MEDICINE AND BIOLOGY 2010; 688:1-23. [PMID: 20919643 DOI: 10.1007/978-1-4419-6741-1_1] [Citation(s) in RCA: 714] [Impact Index Per Article: 51.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/17/2022]
Abstract
Sphingolipids constitute a class of lipids defined by their eighteen carbon amino-alcohol backbones which are synthesized in the ER from nonsphingolipid precursors. Modification of this basic structure is what gives rise to the vast family of sphingolipids that play significant roles in membrane biology and provide many bioactive metabolites that regulate cell function. Despite the diversity of structure and function of sphingolipids, their creation and destruction are governed by common synthetic and catabolic pathways. In this regard, sphingolipid metabolism can be imagined as an array of interconnected networks that diverge from a single common entry point and converge into a single common breakdown pathway. In their simplest forms, sphingosine, phytosphingosine and dihydrosphingosine serve as the backbones upon which further complexity is achieved. For example, phosphorylation of the C1 hydroxyl group yields the final breakdown products and/or the important signaling molecules sphingosine-1-phosphate, phytosphingosine-1-phosphate and dihydrosphingosine-1-phosphate, respectively. On the other hand, acylation of sphingosine, phytosphingosine, or dihydrosphingosine with one of several possible acyl CoA molecules through the action of distinct ceramide synthases produces the molecules defined as ceramide, phytoceramide, or dihydroceramide. Ceramide, due to the differing acyl CoAs that can be used to produce it, is technically a class of molecules rather than a single molecule and therefore may have different biological functions depending on the acyl chain it is composed of. At the apex of complexity is the group of lipids known as glycosphingolipids (GSL) which contain dozens of different sphingolipid species differing by both the order and type of sugar residues attached to their headgroups. Since these molecules are produced from ceramide precursors, they too may have differences in their acyl chain composition, revealing an additional layer of variation. The glycosphingolipids are divided broadly into two categories: glucosphingolipids and galactosphingolipids. The glucosphingolipids depend initially on the enzyme glucosylceramide synthase (GCS) which attaches glucose as the first residue to the C1 hydroxyl position. Galactosphingolipids, on the other hand, are generated from galactosylceramide synthase (GalCerS), an evolutionarily dissimilar enzyme from GCS. Glycosphingolipids are further divided based upon further modification by various glycosyltransferases which increases the potential variation in lipid species by several fold. Far more abundant are the sphingomyelin species which are produced in parallel with glycosphingolipids, however they are defined by a phosphocholine headgroup rather than the addition of sugar residues. Although sphingomyelin species all share a common headgroup, they too are produced from a variety of ceramide species and therefore can have differing acyl chains attached to their C-2 amino groups. Whether or not the differing acyl chain lengths in SMs dictate unique functions or important biophysical distinctions has not yet been established. Understanding the function of all the existing glycosphingolipids and sphingomyelin species will be a major undertaking in the future since the tools to study and measure these species are only beginning to be developed (see Fig 1 for an illustrated depiction of the various sphingolipid structures). The simple sphingolipids serve both as the precursors and the breakdown products of the more complex ones. Importantly, in recent decades, these simple sphingolipids have gained attention for having significant signaling and regulatory roles within cells. In addition, many tools have emerged to measure the levels of simple sphingolipids and therefore have become the focus of even more intense study in recent years. With this thought in mind, this chapter will pay tribute to the complex sphingolipids, but focus on the regulation of simple sphingolipid metabolism.
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Affiliation(s)
- Christopher R Gault
- Department of Biochemistry, Medical University of South Carolina, Charleston, South Carolina 29425, USA
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21
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Wu BX, Zeidan YH, Hannun YA. Downregulation of neutral ceramidase by gemcitabine: Implications for cell cycle regulation. Biochim Biophys Acta Mol Cell Biol Lipids 2009; 1791:730-9. [PMID: 19345744 DOI: 10.1016/j.bbalip.2009.03.012] [Citation(s) in RCA: 31] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/19/2008] [Revised: 02/24/2009] [Accepted: 03/17/2009] [Indexed: 01/01/2023]
Abstract
Gemcitabine (GMZ) is a chemotherapeutic agent with well established effects on cell growth arrest and apoptosis. In this study, we investigated the potential roles of bioactive sphingolipids in mediating the growth suppressing effects of GMZ on a polyoma middle T transformed murine endothelial cell line. After 12-hour GMZ (0.6 microM) treatment, cell growth was arrested at the G(0)/G(1) phase as detected by flow cytometric cell cycle analysis and MTT cell viability analysis, and this was accompanied by dephosphorylation of the retinoblastoma protein (Rb). Furthermore, GMZ treatment resulted in increased levels of specifically the very long chain ceramides as determined by mass spectrometry. Mechanistically, GMZ did not appear to affect the activities of many enzymes of ceramide metabolism; however, GMZ caused a selective reduction in the protein levels of neutral ceramidase (NCDase), as indicated by Western blot analysis, with a concomitant decrease in NCDase activity. The significance of NCDase loss on cell cycle regulation was investigated by specific knockdown of the enzyme using small interfering RNA (siRNA). Interestingly, NCDase siRNA transfection was sufficient to induce a cell cycle arrest at G(0)/G(1) and an increase in total ceramide levels, with significant elevation in very long chain ceramides (C(24:1) and C(24:0)). NCDase siRNA also induced Rb dephosphorylation. These data provide evidence for a novel mechanism of action for GMZ and highlight downregulation of NCDase as a critical step in GMZ-mediated ceramide elevation and cell cycle arrest.
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Affiliation(s)
- Bill X Wu
- Department of Biochemistry and Molecular Biology, Medical University of South Carolina, Charleston, 29425, USA
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22
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Ceramidases: regulators of cellular responses mediated by ceramide, sphingosine, and sphingosine-1-phosphate. Biochim Biophys Acta Mol Cell Biol Lipids 2008; 1781:424-34. [PMID: 18619555 DOI: 10.1016/j.bbalip.2008.06.002] [Citation(s) in RCA: 300] [Impact Index Per Article: 18.8] [Reference Citation Analysis] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/02/2008] [Revised: 06/02/2008] [Accepted: 06/04/2008] [Indexed: 11/22/2022]
Abstract
Ceramidases catalyze hydrolysis of ceramides to generate sphingosine (SPH), which is phosphorylated to form sphingosine-1-phosphate (S1P). Ceramide, SPH, and S1P are bioactive lipids that mediate cell proliferation, differentiation, apoptosis, adhesion, and migration. Presently, 5 human ceramidases encoded by 5 distinct genes have been cloned: acid ceramidase (AC), neutral ceramidase (NC), alkaline ceramidase 1 (ACER1), alkaline ceramidase 2 (ACER2), and alkaline ceramidase 3 (ACER3). Each human ceramidase has a mouse counterpart. AC, NC, and ACER1-3 have maximal activities in acidic, neutral, and alkaline environments, respectively. ACER1-3 have similar protein sequences but no homology to AC and NC. AC and NC also have distinct protein sequences. The human AC (hAC) was implicated in Farber disease, and hAC may be important for cell survival. The mouse AC (mAC) is needed for early embryo survival. NC is protective against inflammatory cytokines, and the mouse NC (mNC) is required for the catabolism of ceramides in the digestive tract. ACER1 is critical in mediating cell differentiation by controlling the generation of SPH and S1P and that ACER2's role in cell proliferation and survival depends on its expression or the cell type in which it is found. Here, we discuss the role of each ceramidase in regulating cellular responses mediated by ceramides, SPH, and S1P.
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23
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Bedia C, Casas J, Garcia V, Levade T, Fabriàs G. Synthesis of a Novel Ceramide Analogue and its Use in a High-Throughput Fluorogenic Assay for Ceramidases. Chembiochem 2007; 8:642-8. [PMID: 17361980 DOI: 10.1002/cbic.200600533] [Citation(s) in RCA: 47] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/02/2023]
Abstract
Several investigations have shown that acid ceramidase inhibitors are potential antiproliferative and cytostatic drugs for cancer chemotherapy. The combinatorial chemistry approach for the discovery of acid ceramidase inhibitors requires the availability of a high-throughput enzyme assay. The synthesis of a novel fluorogenic ceramidase substrate, and its processing both in vitro and in cultured cells in a microtiter plate layout, are reported in this article. This coumarinic substrate was hydrolyzed in vitro (rat liver lysosomes) with Km and Vmax values of 113 microM and 3.6 pmol min-1 mg-1, respectively. Similarly, hydrolysis occurred in intact cultured cells that overexpressed acidic ceramidase. The assay was validated for the identification and characterization of acidic ceramidase inhibitors by using several alpha-ketoamide ceramide analogues, whose inhibitory activity had been previously described.
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Affiliation(s)
- Carmen Bedia
- Research Unit on BioActive Molecules, Departamento de Química Orgánica Biológica, Instituto de Investigaciones Químicas y Ambientales de Barcelona, CSIC, Jordi Girona 18, 08034 Barcelona, Spain
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24
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Houben E, Uchida Y, Nieuwenhuizen WF, De Paepe K, Vanhaecke T, Holleran WM, Rogiers V. Kinetic Characteristics of Acidic and Alkaline Ceramidase in Human Epidermis. Skin Pharmacol Physiol 2007; 20:187-94. [PMID: 17396053 DOI: 10.1159/000101388] [Citation(s) in RCA: 17] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/24/2006] [Accepted: 12/22/2006] [Indexed: 11/19/2022]
Abstract
It has recently become evident that at least five ceramidase (CDase) isoforms are present in human epidermis, and that specifically acidic CDase (aCDase) and alkaline CDase (alkCDase) activities increase during keratinocyte differentiation, and thus might play a pivotal role(s) in permeability barrier function. Prior to investigating their possible roles in the epidermal barrier function, it is necessary to characterize basic kinetic parameters for these enzymes, as well as to determine the effects of the established CDase inhibitors and their activities. In this study, assays for both aCDase and alkCDase activities in fully differentiated human epidermis were optimized using a radiolabeled substrate. These studies revealed that aCDase activity is substantially higher than alkCDase activity, and that both isoenzymes are inhibited by a CDase inhibitor N-oleylethanolamine. These findings were also confirmed using an in situ enzyme assay.
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Affiliation(s)
- E Houben
- Department of Toxicology, Dermato-Cosmetology and Pharmacognosy, Vrije Universiteit Brussel, Brussels, Belgium.
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25
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Choi MS, Anderson MA, Zhang Z, Zimonjic DB, Popescu N, Mukherjee AB. Neutral ceramidase gene: role in regulating ceramide-induced apoptosis. Gene 2003; 315:113-22. [PMID: 14557071 DOI: 10.1016/s0378-1119(03)00721-2] [Citation(s) in RCA: 27] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/17/2022]
Abstract
The sphingolipid, ceramide, is a natural dietary constituent and a potent mediator of apoptosis. If left undegraded, it may induce apoptosis and cause disruption of cellular integrity. A potential mechanism to prevent ceramide-induced apoptosis in various organs may involve ceramidases that facilitate the degradation of ceramide. In this study, we first isolated and characterized the murine neutral ceramidase (N-CDase) gene, mapped its chromosomal location and determined its developmental and organ-specific expression. Then we used cultured mesangial cells as our in vitro model and mouse gastrointestinal (GI) tract as the in vivo model to determine the effects of an inhibitor of N-CDase, D-erythro-MAPP, to delineate whether N-CDase plays a role in preventing ceramide-induced apoptosis. Our results show that: (i) the structure of the murine neutral ceramidase gene is virtually identical to that of the human gene; (ii) it is localized on chromosome 19 at bands C2-C3 that is syntenic to human chromosome 10q24-26; (iii) N-CDase expression is developmentally regulated and it is expressed at high levels in cultured mesangial cells and in specific regions of the mouse small intestine; (iv) inhibition of N-CDase by D-erythro-MAPP leads to increased ceramide levels and consequent apoptosis in cultured mesangial cells; (v) mice treated with D-erythro-MAPP alone also caused apoptosis in the small intestine; and (vi) mice treated with D-erythro-MAPP prior to feeding C2 ceramide manifest markedly elevated levels of apoptosis in the GI tract raising the possibility that neutral ceramidase plays a detoxifying role against inadvertent stimulation of ceramide-induced apoptosis in organs that come in contact with this sphingolipid. We propose that N-CDase is an essential component of an innate detoxifying mechanism to prevent ceramide-induced apoptosis.
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MESH Headings
- Amidohydrolases/antagonists & inhibitors
- Amidohydrolases/genetics
- Amidohydrolases/physiology
- Animals
- Apoptosis/drug effects
- Base Sequence
- Blotting, Northern
- Blotting, Western
- Cell Line
- Ceramidases
- Ceramides/metabolism
- Ceramides/pharmacology
- Chromosome Mapping
- Dose-Response Relationship, Drug
- Exons
- Gene Expression
- Gene Expression Regulation, Developmental
- Gene Expression Regulation, Enzymologic
- Genes/genetics
- Humans
- In Situ Hybridization, Fluorescence
- In Situ Nick-End Labeling
- Introns
- Male
- Mice
- Mice, Inbred C57BL
- Mitochondria/enzymology
- Molecular Sequence Data
- Myristates/pharmacology
- Neutral Ceramidase
- Propanolamines/pharmacology
- RNA, Messenger/genetics
- RNA, Messenger/metabolism
- Sequence Analysis, DNA
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Affiliation(s)
- Moonsuk S Choi
- Section on Developmental Genetics, Heritable Disorders Branch, The National Institute of Child Health and Human Development, The National Institutes of Health, Room 9S241, Building 10, Bethesda, MD 20892-1830, USA
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26
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Lundgren P, Nilsson A, Duan RD. Distribution and properties of neutral ceramidase activity in rat intestinal tract. Dig Dis Sci 2001; 46:765-72. [PMID: 11330410 DOI: 10.1023/a:1010792031910] [Citation(s) in RCA: 29] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 12/09/2022]
Abstract
Ceramide plays an important role in regulating cell proliferation and apoptosis. Recent studies indicate that generation of ceramide in the intestine from sphingomyelin hydrolysis may be implicated in colon cancer development. The enzymes that catalyze the further hydrolysis of ceramide in the intestine have, however, not been well investigated. Our data reveal the existence of a ceramidase (EC 3.5.1.23) in rat intestinal mucosa with an optimal pH of 7.0. One milligram of mucosal protein is able to hydrolyze 44.0+/-9.6 nmol of ceramide in 1 hr. The activity is low in the proximal duodenum and increases to a plateau in the proximal jejunum. The activity is then similar throughout the small intestine, until it declines in the distal part of ileum. Some activity is also detectable in the colon. The activity increases slightly in the presence of monomeric bile salt concentrations and sharply at the critical micellar concentration. Similar patterns were observed for both primary (taurocholate) and secondary (taurodeoxycholate) bile salts. The addition of Triton X-100 enhances the ceramidase activity at optimal bile salt concentration. The reaction is linear with time for the first 20 min and the hydrolytic rate declines slowly thereafter. Finally, the activity shows a considerable resistance against tryptic degradation, as 71% of the ceramidase activity remained when the homogenates were preincubated with high concentrations of trypsin. Intestinal mucosa also has a ceramide synthesis activity, with a distribution pattern generally paralleling ceramide hydrolysis activity. In conclusion, intestinal neutral ceramidase has a distinct distribution pattern and bile salt dependence, which enables it to collaborate with intestinal sphingomyelinase in hydrolysis of sphingomyelin.
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Affiliation(s)
- P Lundgren
- Department of Cell Biology 1, University Hospital of Lund, Sweden
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27
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Yeager AM, Uhas KA, Coles CD, Davis PC, Krause WL, Moser HW. Bone marrow transplantation for infantile ceramidase deficiency (Farber disease). Bone Marrow Transplant 2000; 26:357-63. [PMID: 10967581 DOI: 10.1038/sj.bmt.1702489] [Citation(s) in RCA: 61] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/09/2022]
Abstract
Infantile ceramidase deficiency (Farber disease) is an uncommon, progressive lysosomal storage disease characterized by multiple ceramide-containing nodules (lipogranulomata) in the subcutaneous tissue and upper aerodigestive tract, painful periarticular swelling, psychomotor retardation, and varying degrees of ocular, pulmonary or hepatic involvement. Management of Farber disease has been limited to symptomatic supportive care, and few affected infants survive beyond 5 years of age. We performed an allogeneic bone marrow transplant (BMT) from an HLA-identical heterozygous sister in a 9.5-month-old female with minimally symptomatic Farber disease who received a pre-transplant regimen of busulfan and cyclophosphamide. Ceramidase activity in peripheral blood leukocytes increased from 6% before transplant to 44% (donor heterozygote level) by 6 weeks after BMT. By 2 months after transplant, the patient's subcutaneous lipogranulomata, pain on joint motion, and hoarseness had resolved. Despite modest gains in cognitive and language development, hypotonia and delayed motor skills persisted. Gradual loss of circulating donor cells with autologous hematopoietic recovery occurred; VNTR analyses showed 50% donor DNA in peripheral blood cells at 8.5 months after BMT and only 1% at 21 months after transplant. Interestingly, leukocyte ceramidase activity consistently remained in the heterozygous range despite attrition of donor cells in peripheral blood. This novel observation indicates ongoing hydrolase production by non-circulating donor cells, possibly in the mononuclear phagocytic system, and uptake by recipient leukocytes. Although lipogranulomata and hoarseness did not recur, the patient's neurological and neurocognitive status progressively declined. She died 28 months after BMT (age 37.5 months) with pulmonary insufficiency caused by recurrent aspiration pneumonias. Allogeneic BMT improves the peripheral manifestations of infantile ceramidase deficiency, but may not prevent the progressive neurological deterioration, even when carried out in minimally symptomatic patients.
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Affiliation(s)
- A M Yeager
- Stem Cell Transplant Program, Department of Medicine, Winship Cancer Institute, Emory University School of Medicine, Atlanta, GA, USA
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28
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Augé N, Nègre-Salvayre A, Salvayre R, Levade T. Sphingomyelin metabolites in vascular cell signaling and atherogenesis. Prog Lipid Res 2000; 39:207-29. [PMID: 10799716 DOI: 10.1016/s0163-7827(00)00007-2] [Citation(s) in RCA: 83] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/10/2023]
Abstract
The atherosclerotic lesion most probably develops through a number of cellular events which implicate all vascular cell types and include synthesis of extracellular proteins, cell proliferation, differentiation and death. Sphingolipids and sphingolipid metabolizing enzymes may play important roles in atherogenesis, not only because of lipoprotein alterations but also by mediating a number of cellular events which are believed to be crucial in the development of the vascular lesions such as proliferation or cell death. Exogenous sphingolipids may mediate various biological effects such as apoptosis, mitogenesis or differentiation depending on the cell type. Moreover, several molecules present in the atherogenic lesion, such as oxidized LDL, growth factors or cytokines, which activate intracellular signaling pathways leading to vascular cell modifications, can stimulate sphingomyelin hydrolysis and generation of ceramide (and other metabolites as sphingosine-1-phosphate). Here we review the potential implication of the sphingomyelin/ceramide cycle in vascular cell signaling related to atherosclerosis, and more generally the role of sphingolipids in the events observed during the atherosclerotic process as cell differentiation, migration, adhesion, retraction, proliferation and death.
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Affiliation(s)
- N Augé
- Laboratoire de Biochimie, INSERM U. 466, "Maladies Métaboliques," Institut Louis Bugnard, Bât. Université Paul Sabatier, CHU Rangueil, 1 Avenue Jean Poulhès, F-31403, Toulouse, France.
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29
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Mao C, Xu R, Bielawska A, Obeid LM. Cloning of an alkaline ceramidase from Saccharomyces cerevisiae. An enzyme with reverse (CoA-independent) ceramide synthase activity. J Biol Chem 2000; 275:6876-84. [PMID: 10702247 DOI: 10.1074/jbc.275.10.6876] [Citation(s) in RCA: 132] [Impact Index Per Article: 5.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022] Open
Abstract
Ceramide is not only a core intermediate of sphingolipids but also an important modulator of many cellular events including apoptosis, cell cycle arrest, senescence, differentiation, and stress responses. Its turnover may be tightly regulated. However, little is known about the regulation of its metabolism because most enzymes responsible for its synthesis and breakdown have yet to be cloned. Here we report the cloning and characterization of the yeast gene YPC1 (YBR183w) by screening Saccharomyces cerevisiae genes whose overexpression bestows resistance to fumonisin B1. We demonstrate that the yeast gene YPC1 encodes an alkaline ceramidase activity responsible for the breakdown of dihydroceramide and phytoceramide but not unsaturated ceramide. YPC1 ceramidase activity was confirmed by in vitro studies using an Escherichia coli expression system. Importantly, YPC1p also has reverse activity, catalyzing synthesis of phytoceramide from palmitic acid and phytosphingosine. This ceramide synthase activity is CoA-independent and is resistant to fumonisin B1, thus explaining why YPC1 was cloned as a fumonisin B1-resistant gene.
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Affiliation(s)
- C Mao
- Division of General Internal Medicine at the Ralph H. Johnson Veterans Administration Hospital and the Departments of Medicine, Charleston, South Carolina 29425, USA
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30
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He X, Li CM, Park JH, Dagan A, Gatt S, Schuchman EH. A fluorescence-based high-performance liquid chromatographic assay to determine acid ceramidase activity. Anal Biochem 1999; 274:264-9. [PMID: 10527524 DOI: 10.1006/abio.1999.4284] [Citation(s) in RCA: 29] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022]
Abstract
Acid ceramidase (N-acylsphingosine amidohydrolase) is the lysosomal enzyme required to hydrolyze the N-acyl linkage between the fatty acid and sphingosine moieties in ceramide. A deficiency of acid ceramidase activity results in the lipid storage disorder, Farber disease. This study reports a new assay method to detect acid ceramidase activity in vitro using Bodipy or lissamine rhodamine-conjugated ceramide (C12 ceramide; dodecanoylsphingosine). Using mouse kidney extracts as the source of acid ceramidase activity, this new method was compared with an assay using radioactive C12 ceramide (N-[(14)C]-dodecanoylsphingosine) as a substrate. The Bodipy C12 ceramide substrate provided data very similar to those of the radioactive substrate, but under the experimental conditions tested, it was significantly more sensitive. Using Bodipy C12 ceramide, femtomole quantities of the product, Bodipy dodecanoic acid, could be detected, providing an accurate measure of acid ceramidase activity as low as 0.1 pmol/mg protein/h. Acid ceramidase activities in skin fibroblasts and EBV-transformed lymphoblasts from Farber disease patients were around 7.8 and 10% of those in normal cells, respectively, confirming the specificity of this new assay method. Based on these results, we suggest that this fluorescence-based, high-performance liquid chromatographic technique is a reliable, rapid, and highly sensitive method to determine acid ceramidase activity, and that it could be useful wherever the in vitro detection of acid ceramidase activity is of importance.
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Affiliation(s)
- X He
- Department of Human Genetics, Mount Sinai School of Medicine, New York, New York, 10029, USA
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31
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El Bawab S, Bielawska A, Hannun YA. Purification and characterization of a membrane-bound nonlysosomal ceramidase from rat brain. J Biol Chem 1999; 274:27948-55. [PMID: 10488143 DOI: 10.1074/jbc.274.39.27948] [Citation(s) in RCA: 77] [Impact Index Per Article: 3.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022] Open
Abstract
We have purified a membrane bound ceramidase 22,300-fold to apparent homogeneity. The purification scheme included Triton X-100 extraction of membranes followed by Q-Sepharose, blue Sepharose, phenyl-Sepharose, and MonoS column chromatography. The purified enzyme showed an apparent molecular mass of 90 kDa as estimated by SDS-polyacrylamide gel electrophoresis under reducing conditions and 95 kDa by chromatography on Superose 12. Using C(16)-ceramide as substrate, the enzyme showed a broad pH optimum in the neutral to alkaline range. A mixed micelle assay was developed, and using Triton X-100/ceramide mixed micelles, the enzyme exhibited classical Michaelis-Menten kinetics, with a K(m) of 1.29 mol % and a V(max) of 4.4 micromol/min/mg. When dihydroceramide was used as substrate, these values were 3.84 mol % and 1.2 micromol/min/mg, respectively, indicating that the enzyme hydrolyzes ceramides preferentially. The activity of the purified ceramidase did not require cations, and it was inhibited by reducing agents. Phosphatidylcholine and sphingomyelin were without effect on the enzyme activity, whereas phosphatidic acid and phosphatidylserine stimulated the activity 3-fold. Sphingosine acted as a competitive inhibitor with an IC(50) of 5-10 microM. These results indicate that the purified enzyme is a novel ceramidase.
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Affiliation(s)
- S El Bawab
- Department of Biochemistry and Molecular Biology, Medical University of South Carolina, Charleston, South Carolina 29425, USA
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32
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33
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Medin JA, Takenaka T, Carpentier S, Garcia V, Basile JP, Segui B, Andrieu-Abadie N, Auge N, Salvayre R, Levade T. Retrovirus-mediated correction of the metabolic defect in cultured Farber disease cells. Hum Gene Ther 1999; 10:1321-9. [PMID: 10365663 DOI: 10.1089/10430349950018003] [Citation(s) in RCA: 28] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/13/2022] Open
Abstract
Farber disease is a rare severe lysosomal storage disorder due to a deficient activity of the enzyme acid ceramidase (AC). Patients have granulomas along with lipid-laden macrophages that accumulate in a number of tissues, leading to multiple diverse clinical symptoms. There is no therapy for the disorder and most patients succumb to the disease in early childhood. The severity of the disease progression seems to correlate with the amount of the accumulated ceramide substrate. Since the cDNA for human AC has been elucidated we sought to establish if genetic transfer of this sequence would lead to enzymatic and, especially, functional correction of the catabolic defect in Farber patient cells. To do this, a novel amphotropic recombinant retrovirus was constructed that engineers transfer of the human AC cDNA. On infection of patient fibroblasts, AC enzyme activity in cell extracts was completely restored. Further, substrate-loading assays of intact living cells showed a fully normalized catabolism of lysosomal ceramide. Lastly, as reported for some other corrected enzymatic defects of lysosomes, metabolic cooperativity was seen, in that functionally corrected patient fibroblasts secreted AC that was taken up through the mannose 6-phosphate receptor and used by uncorrected fibroblasts as well as recipient Farber lymphoblastoid cells. This overall transduction and uptake scenario for Farber disease allows future treatment of this severe disorder to be envisioned using gene transfer approaches.
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Affiliation(s)
- J A Medin
- Department of Medicine, University of Illinois at Chicago, 60607-7173, USA.
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34
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van Echten-Deckert G, Klein A, Linke T, Heinemann T, Weisgerber J, Sandhoff K. Turnover of endogenous ceramide in cultured normal and Farber fibroblasts. J Lipid Res 1997. [DOI: 10.1016/s0022-2275(20)30041-9] [Citation(s) in RCA: 14] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/22/2022] Open
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35
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36
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Chatelut M, Feunteun J, Harzer K, Fensom AH, Basile JP, Salvayre R, Levade T. A simple method for screening for Farber disease on cultured skin fibroblasts. Clin Chim Acta 1996; 245:61-71. [PMID: 8646815 DOI: 10.1016/0009-8981(95)06173-8] [Citation(s) in RCA: 22] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/01/2023]
Abstract
Farber disease is an inborn lysosomal storage disorder characterized by accumulation of ceramide in the patient's tissues due to the deficient activity of acid ceramidase. Currently, confirmation of the diagnosis is performed in an extremely limited number of laboratories. We therefore developed a procedure which does not require any particular sphingolipid substrate and is based on the quantitation of ceramide levels in cultured skin fibroblasts. In the method we devised, the ceramide present in cellular lipid extracts subjected to mild alkaline hydrolysis was quantified using the commercially available diacylglycerol kinase kit. We show that both primary cultures of skin fibroblasts and SV40-transformed fibroblasts derived from a series of patients with Farber disease exhibit ceramide excess as compared to their normal counterparts (2345-17 153 pmol/mg cell protein in Farber cells vs. 432-1298 pmol/mg cell protein in controls). Use of this simple method should greatly facilitate the biochemical diagnosis of Farber disease.
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Affiliation(s)
- M Chatelut
- Laboratoire de Biochimie, CJF INSERM 9206. Toulouje, France
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37
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Affiliation(s)
- W J Johnson
- Department of Biochemistry, MCP Hahnemann School of Medicine, Allegheny University of the Health Sciences, Philadelphia, Pennsylvania 19129, USA
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38
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Nowaczyk MJ, Feigenbaum A, Silver MM, Callahan J, Levin A, Jay V. Bone marrow involvement and obstructive jaundice in Farber lipogranulomatosis: clinical and autopsy report of a new case. J Inherit Metab Dis 1996; 19:655-60. [PMID: 8892023 DOI: 10.1007/bf01799842] [Citation(s) in RCA: 15] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 02/02/2023]
Abstract
We report a case of Farber lipogranulomatosis in a girl with hepatosplenomegaly, macular cherry-red spot, and subcutaneous nodules who developed liver dysfunction with jaundice and ascites, and myelophthisic anaemia because of infiltration of bone marrow with storage cells. Acid ceramidase assay confirmed the diagnosis. We conclude that the bone marrow dysfunction and cherry-red spot are features of type IV Farber lipogranulomatosis that have not been previously recognized, and should be added to the clinical phenotypic description.
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Affiliation(s)
- M J Nowaczyk
- Division of Clinical Genetics, University of Toronto, Ontario, Canada
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39
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Levade T, Moser HW, Fensom AH, Harzer K, Moser AB, Salvayre R. Neurodegenerative course in ceramidase deficiency (Farber disease) correlates with the residual lysosomal ceramide turnover in cultured living patient cells. J Neurol Sci 1995; 134:108-14. [PMID: 8747852 DOI: 10.1016/0022-510x(95)00231-0] [Citation(s) in RCA: 54] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/02/2023]
Abstract
Farber's lipogranulomatosis is an inborn lipid storage disease characterized by tissue accumulation of ceramide due to deficient activity of lysosomal ceramidase. Symptoms include painful swelling of joints, subcutaneous nodules, a hoarse cry, hepatosplenomegaly and nervous system dysfunction of markedly variable degree. In most cases the neural dysfunction rather than the general dystrophy, seems to limit the duration of Farber disease. We examined whether the severity can be shown as a function of ceramide turnover by lysosomal ceramidase. The lysosomal degradation of sphingomyelin-derived ceramide was studied in situ in patient skin fibroblasts and lymphoid cells loaded with LDL-associated radioactive sphingomyelin. We could show for the first time a significant correlation between the ceramide accumulated in situ and the severity of Farber disease. Our method provides an alternative means for determining ceramide degradation by lysosomal ceramidase, but in intact cells. The relatively simple method is at least of the same diagnostic use for Farber disease as the in vitro assay of acid ceramidase using cell homogenates and may also have some prognostic use.
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Affiliation(s)
- T Levade
- CJF INSERM 9206, C.H.U. Rangueil, Toulouse, France
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40
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Levade T, Tempesta MC, Salvayre R. The in situ degradation of ceramide, a potential lipid mediator, is not completely impaired in Farber disease. FEBS Lett 1993; 329:306-12. [PMID: 8365472 DOI: 10.1016/0014-5793(93)80243-n] [Citation(s) in RCA: 24] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/30/2023]
Abstract
The time course of degradation of a radiolabelled natural ceramide has been studied in intact, living lymphoid cells and skin fibroblasts from normal individuals and from patients affected with Farber disease, an inborn disorder of ceramide metabolism due to deficient activity of lysosomal ceramidase. The hydrolysis of ceramide in lysosomes was selectively followed by examining the turnover of an LDL-associated radioactive sphingomyelin. This permitted to estimate accurately the effective lysosomal ceramidase activity and to demonstrate: (i) a very active catabolism of ceramide in normal cells; and (ii) the absence of a complete block of ceramide degradation in Farber cells. The possible implication of ceramide as a lipid mediator of the pathogenesis of Farber disease is discussed.
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Affiliation(s)
- T Levade
- Maladies Métaboliques, CJF INSERM 9206, Institut Louis Bugnard, CHU Rangueil, Toulouse, France
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41
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Zappatini-Tommasi L, Dumontel C, Guibaud P, Girod C. Farber disease: an ultrastructural study. Report of a case and review of the literature. VIRCHOWS ARCHIV. A, PATHOLOGICAL ANATOMY AND HISTOPATHOLOGY 1992; 420:281-90. [PMID: 1553820 DOI: 10.1007/bf01600282] [Citation(s) in RCA: 22] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/27/2022]
Abstract
A case of Farber disease is reported and the ultrastructural pathology of the disease is reviewed. The present case showed the typical clinical picture of Farber disease. Acid ceramidase deficiency was demonstrated biochemically. Ultrastructural features of one subcutaneous nodule and a skin biopsy are described. Three lysosomal inclusions characterize Farber disease: curvilinear tubular bodies observed mainly in the reticuloendothelial system, "banana bodies" recorded only in the peripheral nervous system and zebra-like bodies which are essentially a neuronal storage. The nature of each is discussed and the skin biopsy is emphasized for its important diagnostic interest.
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42
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Fujiwaki T, Hamanaka S, Koga M, Ishihara T, Nishikomori R, Kinoshita E, Furusho K. A case of Farber disease. ACTA PAEDIATRICA JAPONICA : OVERSEAS EDITION 1992; 34:72-9. [PMID: 1580156 DOI: 10.1111/j.1442-200x.1992.tb00928.x] [Citation(s) in RCA: 13] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/27/2022]
Abstract
We report a case of Farber disease (Farber lipogranulomatosis). The main features were a shrill voice, joint swelling, subcutaneous nodules and retarded psychomotor development. Cytological investigation revealed intracytoplasmic inclusion bodies characteristic of Farber disease. Lipid analysis of liver tissue indicated an accumulation of ceramide containing non-hydroxy fatty acids. It was found that the acid ceramidase activity in the liver was reduced to 31% of the control value. In this patient there was also persistent diarrhea, cholelithiasis, transient proteinuria and increased urinary total sialic acids. These features have not been noted in previously reported cases.
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Affiliation(s)
- T Fujiwaki
- Department of Pediatrics, Kokura Memorial Hospital, Japan
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43
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Abstract
This comprehensive review was necessitated by recent observations suggesting that sphingomyelin and derivatives may serve second messenger functions. It has attempted to remain true to the theme of cellular signalling. Hence, it has focussed on the lipids involved primarily with respect to their metabolism and properties in mammalian systems. The enzymology involved has been emphasized. An attempt was made to define directions in which signals may be flowing. However, the evidence presented to date is insufficient to conclusively designate the mechanisms of stimulated lipid metabolism. Hence, the proposed pathways must be viewed as preliminary. Further, the biologic functions of these lipids is for the most part uncertain. Thus, it is difficult to presently integrate this sphingomyelin pathway into the greater realm of cell biology. Nevertheless, the present evidence appears to suggest that a sphingomyelin pathway is likely to possess important bioregulatory functions. Hopefully, interest in this novel pathway will grow and allow a more complete understanding of the roles of these sphingolipids in physiology and pathology.
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Affiliation(s)
- R N Kolesnick
- Program of Molecular Pharmacology and Therapeutics, Memorial Sloan-Kettering Cancer Center, Cornell University Medical Center, New York, NY 10021
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44
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Al BJ, Tiffany CW, Gomes de Mesquita DS, Moser HW, Tager JM, Schram AW. Properties of acid ceramidase from human spleen. BIOCHIMICA ET BIOPHYSICA ACTA 1989; 1004:245-51. [PMID: 2526656 DOI: 10.1016/0005-2760(89)90274-9] [Citation(s) in RCA: 19] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/01/2023]
Abstract
We have characterised ceramidase activity in extracts of human spleen from control subjects and from patients with Gaucher disease. In Triton X-100 extracts of control spleens, a broad pH optimum of pH 3.5-5.0 was found; no ceramidase activity was detectable at neutral or alkaline pH. About 45-60% of acid ceramidase could be extracted from spleen without detergents, but for complete extraction, Triton X-100 was required. For the radiolabelled substrate oleoylsphingosine, a Km of 0.22 +/- 0.09 mM and a Vmax of 57 +/- 11 nmol/h per mg protein was calculated in spleen from a control subject. Flat-bed isoelectric focussing in the presence of Triton X-100 revealed a pI of 6.0-7.0 for acid ceramidase; similar values were found for sphingomyelinase and glucerebrosidase. HPLC-gel filtration indicated that in the presence of Triton X-100, acid ceramidase has an Mr of about 100 kDa. In the absence of detergents, the enzyme forms high-molecular-weight aggregates. Similar aggregation behaviour was observed for sphingomyelinase, while the elution of beta-hexosaminidase was not affected by detergents. The elution profile of glucocerebrosidase was only slightly altered by Triton X-100. There was no difference in the properties of acid ceramidase present in spleen from control subjects and from patients with type I Gaucher disease.
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Affiliation(s)
- B J Al
- Department of Biochemistry, Faculty of Medicine, University of Amsterdam, The Netherlands
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45
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Ben-Yoseph Y, Gagné R, Parvathy MR, Mitchell DA, Momoi T. Leukocyte and plasma N-laurylsphingosine deacylase (ceramidase) in Farber disease. Clin Genet 1989; 36:38-42. [PMID: 2504515 DOI: 10.1111/j.1399-0004.1989.tb03364.x] [Citation(s) in RCA: 20] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/01/2023]
Abstract
Severe deficiency of acid ceramidase activity (4-5% of normal) was demonstrated in cultured skin fibroblasts, leukocytes and plasma from a 1-year-old boy who was diagnosed as being affected with Farber disease. Determination of ceramidase activity in plasma was achieved by a highly sensitive assay employing a ceramide substrate containing radiolabeled C12 N-acyl moiety (N-lauryl). The enzyme activity in the parents' leukocytes and plasma was found to be reduced to 18-47% of the respective normal values, and that determined in a plasma specimen from a patient with I-cell disease was about 4 times elevated above the normal level.
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Affiliation(s)
- Y Ben-Yoseph
- C. S. Mott Center for Human Growth and Development, Wayne State University School of Medicine, Detroit, Michigan
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46
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Stein O, Oette K, Hollander G, Dabach Y, Ben-Naim M, Stein Y. Divergent fate of unsaturated and saturated ceramides and sphingomyelins in rat liver and cells in culture. BIOCHIMICA ET BIOPHYSICA ACTA 1989; 1003:175-82. [PMID: 2730890 DOI: 10.1016/0005-2760(89)90252-x] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/02/2023]
Abstract
The metabolism of sphingomyelins and ceramides with defined labeled fatty acids was compared after injection in vivo or incubation with cultured cells. The liver was the major site of uptake of sphingomyelins and ceramides with 18:2 or 16:0 fatty acids, but with both sphingolipids a higher recovery of radioactivity was found with 16:0 species. The distribution of radioactivity among liver lipids showed that 1.5 h after injection of 18:2 sphingomyelin, only 21% of the label was found as sphingomyelin, and this value was 37% in the case of 16:0 sphingomyelin. There was a very marked difference in the metabolism of 18:2 and 16:0 ceramides. After injection of 18:2 ceramide only 14% of the radioactivity was recovered as sphingomyelin, and this value was more than 50% with 16:0 ceramide. [14C]18:2 ceramide was converted also to glucoceramide and hydrolyzed more extensively than 16:0 ceramide. These observations were extended to sphingomyelins and ceramides with other fatty acids, using Hep-G2 cells in culture. Significantly more radioactivity was recovered as labeled sphingomyelin after incubation with 16:0, 18:0, 20:0 and 24:0 sphingomyelins than with 18:1 and 18:2 sphingomyelins, while more labeled phosphatidylcholine and phosphatidylethanolamine were found with the unsaturated sphingomyelins. In analogy to the findings in vivo, in the Hep-G2 cells more 16:0, 18:0 and 24:0 ceramides were converted to sphingomyelin than 18:1 or 18:2 ceramides. These differences were also seen with cultured macrophages, in which a more marked reutilization for sphingomyelin formation was found with the saturated ceramide series. The sphingomyelin liposomes were tested also for their capacity to mobilize cholesterol, and a rise in plasma unesterified cholesterol occurred after injection of 18:2 sphingomyelin. Marked enhancement of cholesterol efflux from cholesterol ester-loaded macrophages was also seen with 18:1 and 18:2, 20:0 sphingomyelin in the presence of delipidated high-density lipoprotein. The present results demonstrate that the metabolic fate of sphingolipids is related to their fatty acid composition. While ceramides with saturated fatty acids are predominantly reutilized for sphingomyelin formation, those with unsaturated fatty acids undergo probably more rapid hydrolysis with liberation of fatty acids and channeling into glycerolipids.
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Affiliation(s)
- O Stein
- Department of Experimental Medicine and Cancer Research, Hebrew University-Hadassah Medical School, Jerusalem, Israel
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47
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Mitsuo K, Kobayashi T, Shinnoh N, Goto I. A high-performance liquid chromatographic assay for acid ceramidase activity in cultured fibroblasts from patients with Farber's disease and from controls. Clin Chim Acta 1988; 173:281-7. [PMID: 3383428 DOI: 10.1016/0009-8981(88)90015-0] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/05/2023]
Abstract
The high-performance liquid chromatographic (HPLC) method we devised for assay of acid ceramidase activity involves coupling of a fluorescent probe to the enzymatically released sphingosine in the reaction mixture and detection of the fluorescent sphingosine derivative by reverse-phase HPLC. Using the method, acid ceramidase activity in fibroblast homogenates was accurately assayed, with or without the addition of exogenous ceramide, as the substrate, and the patients and carriers of Farber's disease could be readily diagnosed.
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Affiliation(s)
- K Mitsuo
- Department of Neurology, Faculty of Medicine, Kyushu University, Fukuoka, Japan
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48
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Abstract
A 1-week-old baby boy presented with hepatosplenomegaly, coarse facial features, and cloudy corneas. A metabolic storage disease was considered and he underwent cutaneous and liver biopsy. By light microscopy the skin was normal. Kupffer cells were enlarged and had foamy cytoplasm. Ultrastructural examination of skin and liver demonstrated features compatible with Farber's disease: curvilinear and "banana" bodies, zebra-like structures, and concentric lamellar bodies. A deficiency of lysosomal acid ceramidase was subsequently demonstrated in cultured fibroblasts and in liver tissue corroborating the ultrastructural findings.
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