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Quadri Z, Elsherbini A, Crivelli SM, El‐Amouri SS, Tripathi P, Zhu Z, Ren X, Zhang L, Spassieva SD, Nikolova‐Karakashian M, Bieberich E. Ceramide-mediated orchestration of oxidative stress response through filopodia-derived small extracellular vesicles. J Extracell Vesicles 2024; 13:e12477. [PMID: 38988257 PMCID: PMC11237349 DOI: 10.1002/jev2.12477] [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: 09/10/2023] [Revised: 05/14/2024] [Accepted: 06/18/2024] [Indexed: 07/12/2024] Open
Abstract
Extracellular vesicles (EVs) are shed from the plasma membrane, but the regulation and function of these EVs remain unclear. We found that oxidative stress induced by H2O2 in Hela cells stimulated filopodia formation and the secretion of EVs. EVs were small (150 nm) and labeled for CD44, indicating that they were derived from filopodia. Filopodia-derived small EVs (sEVs) were enriched with the sphingolipid ceramide, consistent with increased ceramide in the plasma membrane of filopodia. Ceramide was colocalized with neutral sphingomyelinase 2 (nSMase2) and acid sphingomyelinase (ASM), two sphingomyelinases generating ceramide at the plasma membrane. Inhibition of nSMase2 and ASM prevented oxidative stress-induced sEV shedding but only nSMase2 inhibition prevented filopodia formation. nSMase2 was S-palmitoylated and interacted with ASM in filopodia to generate ceramide for sEV shedding. sEVs contained nSMase2 and ASM and decreased the level of these two enzymes in oxidatively stressed Hela cells. A novel metabolic labeling technique for EVs showed that oxidative stress induced secretion of fluorescent sEVs labeled with NBD-ceramide. NBD-ceramide-labeled sEVs transported ceramide to mitochondria, ultimately inducing cell death in a proportion of neuronal (N2a) cells. In conclusion, using Hela cells we provide evidence that oxidative stress induces interaction of nSMase2 and ASM at filopodia, which leads to shedding of ceramide-rich sEVs that target mitochondria and propagate cell death.
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Affiliation(s)
- Zainuddin Quadri
- Department of PhysiologyUniversity of Kentucky College of MedicineLexingtonKentuckyUSA
| | - Ahmed Elsherbini
- Department of PhysiologyUniversity of Kentucky College of MedicineLexingtonKentuckyUSA
| | - Simone M. Crivelli
- Department of PhysiologyUniversity of Kentucky College of MedicineLexingtonKentuckyUSA
| | - Salim S. El‐Amouri
- Department of PhysiologyUniversity of Kentucky College of MedicineLexingtonKentuckyUSA
| | - Priyanka Tripathi
- Department of PhysiologyUniversity of Kentucky College of MedicineLexingtonKentuckyUSA
| | - Zhihui Zhu
- Department of PhysiologyUniversity of Kentucky College of MedicineLexingtonKentuckyUSA
| | - Xiaojia Ren
- Department of PhysiologyUniversity of Kentucky College of MedicineLexingtonKentuckyUSA
| | - Liping Zhang
- Department of PhysiologyUniversity of Kentucky College of MedicineLexingtonKentuckyUSA
| | - Stefka D. Spassieva
- Department of PhysiologyUniversity of Kentucky College of MedicineLexingtonKentuckyUSA
| | | | - Erhard Bieberich
- Department of PhysiologyUniversity of Kentucky College of MedicineLexingtonKentuckyUSA
- Veterans Affairs Medical CenterLexingtonKentuckyUSA
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2
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Jamjoum R, Majumder S, Issleny B, Stiban J. Mysterious sphingolipids: metabolic interrelationships at the center of pathophysiology. Front Physiol 2024; 14:1229108. [PMID: 38235387 PMCID: PMC10791800 DOI: 10.3389/fphys.2023.1229108] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/05/2023] [Accepted: 11/27/2023] [Indexed: 01/19/2024] Open
Abstract
Metabolic pathways are complex and intertwined. Deficiencies in one or more enzymes in a given pathway are directly linked with genetic diseases, most of them having devastating manifestations. The metabolic pathways undertaken by sphingolipids are diverse and elaborate with ceramide species serving as the hubs of sphingolipid intermediary metabolism and function. Sphingolipids are bioactive lipids that serve a multitude of cellular functions. Being pleiotropic in function, deficiency or overproduction of certain sphingolipids is associated with many genetic and chronic diseases. In this up-to-date review article, we strive to gather recent scientific evidence about sphingolipid metabolism, its enzymes, and regulation. We shed light on the importance of sphingolipid metabolism in a variety of genetic diseases and in nervous and immune system ailments. This is a comprehensive review of the state of the field of sphingolipid biochemistry.
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Affiliation(s)
- Rama Jamjoum
- Department of Pharmacy, Birzeit University, West Bank, Palestine
| | - Saurav Majumder
- National Institute of Allergy and Infectious Diseases (NIAID), National Institutes of Health, Rockville, MD, United States
| | - Batoul Issleny
- Department of Pharmacy, Birzeit University, West Bank, Palestine
| | - Johnny Stiban
- Department of Biology and Biochemistry, Birzeit University, West Bank, Palestine
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3
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Alizadeh J, da Silva Rosa SC, Weng X, Jacobs J, Lorzadeh S, Ravandi A, Vitorino R, Pecic S, Zivkovic A, Stark H, Shojaei S, Ghavami S. Ceramides and ceramide synthases in cancer: Focus on apoptosis and autophagy. Eur J Cell Biol 2023; 102:151337. [PMID: 37392580 DOI: 10.1016/j.ejcb.2023.151337] [Citation(s) in RCA: 13] [Impact Index Per Article: 13.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/31/2022] [Revised: 05/18/2023] [Accepted: 06/23/2023] [Indexed: 07/03/2023] Open
Abstract
Different studies corroborate a role for ceramide synthases and their downstream products, ceramides, in modulation of apoptosis and autophagy in the context of cancer. These mechanisms of regulation, however, appear to be context dependent in terms of ceramides' fatty acid chain length, subcellular localization, and the presence or absence of their downstream targets. Our current understanding of the role of ceramide synthases and ceramides in regulation of apoptosis and autophagy could be harnessed to pioneer the development of new treatments to activate or inhibit a single type of ceramide synthase, thereby regulating the apoptosis induction or cross talk of apoptosis and autophagy in cancer cells. Moreover, the apoptotic function of ceramide suggests that ceramide analogues can pave the way for the development of novel cancer treatments. Therefore, in the current review paper we discuss the impact of ceramide synthases and ceramides in regulation of apoptosis and autophagy in context of different types of cancers. We also briefly introduce the latest information on ceramide synthase inhibitors, their application in diseases including cancer therapy, and discuss approaches for drug discovery in the field of ceramide synthase inhibitors. We finally discussed strategies for developing strategies to use lipids and ceramides analysis in biological fluids for developing early biomarkers for cancer.
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Affiliation(s)
- Javad Alizadeh
- Department of Human Anatomy and Cell Science, Max Rady College of Medicine, Rady Faculty of Health Sciences, University of Manitoba, Winnipeg, MB R3T 2N2, Canada
| | - Simone C da Silva Rosa
- Department of Human Anatomy and Cell Science, Max Rady College of Medicine, Rady Faculty of Health Sciences, University of Manitoba, Winnipeg, MB R3T 2N2, Canada
| | - Xiaohui Weng
- Department of Chemistry & Biochemistry, California State University, Fullerton, 800 N. State College, Fullerton, CA 92834, United States
| | - Joadi Jacobs
- Department of Human Anatomy and Cell Science, Max Rady College of Medicine, Rady Faculty of Health Sciences, University of Manitoba, Winnipeg, MB R3T 2N2, Canada
| | - Shahrokh Lorzadeh
- Department of Human Anatomy and Cell Science, Max Rady College of Medicine, Rady Faculty of Health Sciences, University of Manitoba, Winnipeg, MB R3T 2N2, Canada
| | - Amir Ravandi
- Department of Physiology and Pathophysiology, Rady Faculty of Health Sciences, University of Manitoba, 66 Chancellors Cir, Winnipeg, MB R3T 2N2, Canada
| | - Rui Vitorino
- UnIC, Department of Surgery and Physiology, Faculty of Medicine, University of Porto, 4200-319 Porto, Portugal; Department of Medical Sciences, Institute of Biomedicine iBiMED, University of Aveiro, 3810-193 Aveiro, Portugal
| | - Stevan Pecic
- Department of Chemistry & Biochemistry, California State University, Fullerton, 800 N. State College, Fullerton, CA 92834, United States
| | - Aleksandra Zivkovic
- Institute of Pharmaceutical and Medicinal Chemistry, Heinrich Heine University Düsseldorf, Universitaetstrasse 1, 40225 Duesseldorf, Germany
| | - Holger Stark
- Institute of Pharmaceutical and Medicinal Chemistry, Heinrich Heine University Düsseldorf, Universitaetstrasse 1, 40225 Duesseldorf, Germany
| | - Shahla Shojaei
- Department of Human Anatomy and Cell Science, Max Rady College of Medicine, Rady Faculty of Health Sciences, University of Manitoba, Winnipeg, MB R3T 2N2, Canada
| | - Saeid Ghavami
- Department of Human Anatomy and Cell Science, Max Rady College of Medicine, Rady Faculty of Health Sciences, University of Manitoba, Winnipeg, MB R3T 2N2, Canada; Faculty of Medicine in Zabrze, University of Technology in Katowice, 41-800 Zabrze, Poland; Research Institute of Oncology and Hematology, Cancer Care Manitoba, University of Manitoba, Winnipeg, MB R3T 2N2, Canada.
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4
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Issleny BM, Jamjoum R, Majumder S, Stiban J. Sphingolipids: From structural components to signaling hubs. Enzymes 2023; 54:171-201. [PMID: 37945171 DOI: 10.1016/bs.enz.2023.07.003] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/12/2023]
Abstract
In late November 2019, Prof. Lina M. Obeid passed away from cancer, a disease she spent her life researching and studying its intricate molecular underpinnings. Along with her husband, Prof. Yusuf A. Hannun, Obeid laid down the foundations of sphingolipid biochemistry and oversaw its remarkable evolution over the years. Lipids are a class of macromolecules that are primarily associated with cellular architecture. In fact, lipids constitute the perimeter of the cell in such a way that without them, there cannot be cells. Hence, much of the early research on lipids identified the function of this class of biological molecules as merely structural. Nevertheless, unlike proteins, carbohydrates, and nucleic acids, lipids are elaborately diverse as they are not made up of monomers in polymeric forms. This diversity in structure is clearly mirrored by functional pleiotropy. In this chapter, we focus on a major subset of lipids, sphingolipids, and explore their historic rise from merely inert structural components of plasma membranes to lively and necessary signaling molecules that transmit various signals and control many cellular processes. We will emphasize the works of Lina Obeid since she was an integral pillar of the sphingolipid research world.
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Affiliation(s)
- Batoul M Issleny
- Department of Pharmacy, Birzeit University, West Bank, Palestine
| | - Rama Jamjoum
- Department of Pharmacy, Birzeit University, West Bank, Palestine
| | | | - Johnny Stiban
- Department of Biology and Biochemistry, Birzeit University, West Bank, Palestine.
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5
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Contribution of specific ceramides to obesity-associated metabolic diseases. Cell Mol Life Sci 2022; 79:395. [PMID: 35789435 PMCID: PMC9252958 DOI: 10.1007/s00018-022-04401-3] [Citation(s) in RCA: 33] [Impact Index Per Article: 16.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/28/2020] [Revised: 05/20/2022] [Accepted: 05/26/2022] [Indexed: 12/04/2022]
Abstract
Ceramides are a heterogeneous group of bioactive membrane sphingolipids that play specialized regulatory roles in cellular metabolism depending on their characteristic fatty acyl chain lengths and subcellular distribution. As obesity progresses, certain ceramide molecular species accumulate in metabolic tissues and cause cell-type-specific lipotoxic reactions that disrupt metabolic homeostasis and lead to the development of cardiometabolic diseases. Several mechanisms for ceramide action have been inferred from studies in vitro, but only recently have we begun to better understand the acyl chain length specificity of ceramide-mediated signaling in the context of physiology and disease in vivo. New discoveries show that specific ceramides affect various metabolic pathways and that global or tissue-specific reduction in selected ceramide pools in obese rodents is sufficient to improve metabolic health. Here, we review the tissue-specific regulation and functions of ceramides in obesity, thus highlighting the emerging concept of selectively inhibiting production or action of ceramides with specific acyl chain lengths as novel therapeutic strategies to ameliorate obesity-associated diseases.
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6
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Lee WK, Maaß M, Quach A, Poscic N, Prangley H, Pallott EC, Kim JL, Pierce JS, Ogretmen B, Futerman AH, Thévenod F. Dependence of ABCB1 transporter expression and function on distinct sphingolipids generated by ceramide synthases-2 and -6 in chemoresistant renal cancer. J Biol Chem 2021; 298:101492. [PMID: 34915026 PMCID: PMC8804196 DOI: 10.1016/j.jbc.2021.101492] [Citation(s) in RCA: 7] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/01/2021] [Accepted: 12/07/2021] [Indexed: 11/18/2022] Open
Abstract
Oncogenic multidrug resistance is commonly intrinsic to renal cancer based on the physiological expression of detoxification transporters, particularly ABCB1, thus hampering chemotherapy. ABCB1 activity is directly dependent on its lipid microenvironment, localizing to cholesterol- and sphingomyelin (SM)-rich domains. As ceramides are the sole source for SMs, we hypothesized that ceramide synthase (CerS)-derived ceramides regulate ABCB1 activity. Using data from RNA-Seq databases, we found that patient kidney tumors exhibited increased CerS2 mRNA, which was inversely correlated with CerS6 mRNA in ABCB1+ clear cell carcinomas. Endogenous elevated CerS2 and lower CerS5/6 mRNA and protein resulted in disproportionately higher CerS2 to CerS5/6 activities (approximately twofold) in chemoresistant ABCB1high (A498, Caki-1) compared with chemosensitive ABCB1low (ACHN, normal human proximal convoluted tubule cell) cells. In addition, lipidomics analyses by HPLC–MS/MS showed bias toward CerS2-associated C20:0/C20:1-ceramides compared with CerS5/6-associated C14:0/C16:0-ceramides (2:1). SMs were similarly altered. We demonstrated that chemoresistance to doxorubicin in ABCB1high cells was partially reversed by inhibitors of de novo ceramide synthesis (l-cycloserine) and CerS (fumonisin B1) in cell viability assays. Downregulation of CerS2/6, but not CerS5, attenuated ABCB1 mRNA, protein, plasma membrane localization, rhodamine 123+ efflux transport activity, and doxorubicin resistance. Similar findings were observed with catalytically inactive CerS6-H212A. Furthermore, CerS6-targeting siRNA shifted ceramide and SM composition to ultra long-chain species (C22–C26). Inhibitors of endoplasmic reticulum–associated degradation (eeyarestatin I) and the proteasome (MG132, bortezomib) prevented ABCB1 loss induced by CerS2/6 downregulation. We conclude that a critical balance in ceramide/SM species is prerequisite to ABCB1 expression and functionalization, which could be targeted to reverse multidrug resistance in renal cancers.
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Affiliation(s)
- Wing-Kee Lee
- Institute for Physiology, Pathophysiology and Toxicology, ZBAF, Witten/Herdecke University, Germany; Physiology & Pathophysiology of Cells and Membranes, Medical School OWL, Bielefeld University, Germany.
| | - Michelle Maaß
- Institute for Physiology, Pathophysiology and Toxicology, ZBAF, Witten/Herdecke University, Germany
| | - Amy Quach
- Institute for Physiology, Pathophysiology and Toxicology, ZBAF, Witten/Herdecke University, Germany; Faculty of Life Sciences, University of Manchester, UK
| | - Nataliya Poscic
- Institute for Physiology, Pathophysiology and Toxicology, ZBAF, Witten/Herdecke University, Germany
| | - Holly Prangley
- Institute for Physiology, Pathophysiology and Toxicology, ZBAF, Witten/Herdecke University, Germany; Faculty of Life Sciences, University of Manchester, UK
| | - Erin-Claire Pallott
- Institute for Physiology, Pathophysiology and Toxicology, ZBAF, Witten/Herdecke University, Germany; Faculty of Life Sciences, University of Manchester, UK
| | - Jiyoon L Kim
- Department of Biomolecular Sciences, Weizmann Institute of Science, Israel
| | - Jason S Pierce
- Lipidomics Shared Resource, Medical University of South Carolina, USA
| | - Besim Ogretmen
- Lipidomics Shared Resource, Medical University of South Carolina, USA; Department of Biochemistry and Molecular Biology, Medical University of South Carolina, USA
| | - Anthony H Futerman
- Department of Biomolecular Sciences, Weizmann Institute of Science, Israel
| | - Frank Thévenod
- Institute for Physiology, Pathophysiology and Toxicology, ZBAF, Witten/Herdecke University, Germany
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7
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Sousa C, Santos FC, Bento-Oliveira A, Mestre B, Silva LC, de Almeida RFM. Biophysical Analysis of Lipid Domains in Mammalian and Yeast Membranes by Fluorescence Spectroscopy. Methods Mol Biol 2021; 2187:247-269. [PMID: 32770511 DOI: 10.1007/978-1-0716-0814-2_14] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 06/11/2023]
Abstract
The use of steady-state and time-resolved fluorescence spectroscopy to study sterol and sphingolipid-enriched lipid domains as diverse as the ones found in mammalian and fungal membranes is herein described. We first address how to prepare liposomes that mimic raft-containing membranes of mammalian cells and how to use fluorescence spectroscopy to characterize the biophysical properties of these membrane model systems. We further illustrate the application of Förster resonance energy transfer (FRET) to study nanodomain reorganization upon interaction with small bioactive molecules, phenolic acids, an important group of phytochemical compounds. This methodology overcomes the resolution limits of conventional fluorescence microscopy allowing for the identification and characterization of lipid domains at the nanoscale.We continue by showing how to use fluorescence spectroscopy in the biophysical analysis of more complex biological systems, namely the plasma membrane of Saccharomyces cerevisiae yeast cells and the necessary adaptations to the filamentous fungus Neurospora crassa , evaluating the global order of the membrane, sphingolipid-enriched domains rigidity and abundance, and ergosterol-dependent properties.
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Affiliation(s)
- Carla Sousa
- Research Institute for medicines (iMed.ULisboa), Faculdade de Farmácia, Universidade de Lisboa, Lisbon, Portugal
| | - Filipa C Santos
- Centro de Química e Bioquímica, Centro de Química Estrutural, Faculdade de Ciências, Universidade de Lisboa, Lisbon, Portugal
| | - Andreia Bento-Oliveira
- Centro de Química e Bioquímica, Centro de Química Estrutural, Faculdade de Ciências, Universidade de Lisboa, Lisbon, Portugal
| | - Beatriz Mestre
- Research Institute for medicines (iMed.ULisboa), Faculdade de Farmácia, Universidade de Lisboa, Lisbon, Portugal
| | - Liana C Silva
- Research Institute for medicines (iMed.ULisboa), Faculdade de Farmácia, Universidade de Lisboa, Lisbon, Portugal
| | - Rodrigo F M de Almeida
- Centro de Química e Bioquímica, Centro de Química Estrutural, Faculdade de Ciências, Universidade de Lisboa, Lisbon, Portugal.
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8
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Ventura A, Varela A, Dingjan T, Santos T, Fedorov A, Futerman A, Prieto M, Silva L. Lipid domain formation and membrane shaping by C24-ceramide. BIOCHIMICA ET BIOPHYSICA ACTA-BIOMEMBRANES 2020; 1862:183400. [DOI: 10.1016/j.bbamem.2020.183400] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/26/2020] [Revised: 06/05/2020] [Accepted: 06/15/2020] [Indexed: 01/29/2023]
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9
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Crivelli SM, Giovagnoni C, Visseren L, Scheithauer AL, de Wit N, den Hoedt S, Losen M, Mulder MT, Walter J, de Vries HE, Bieberich E, Martinez-Martinez P. Sphingolipids in Alzheimer's disease, how can we target them? Adv Drug Deliv Rev 2020; 159:214-231. [PMID: 31911096 DOI: 10.1016/j.addr.2019.12.003] [Citation(s) in RCA: 44] [Impact Index Per Article: 11.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/19/2019] [Revised: 10/09/2019] [Accepted: 12/31/2019] [Indexed: 01/06/2023]
Abstract
Altered levels of sphingolipids and their metabolites in the brain, and the related downstream effects on neuronal homeostasis and the immune system, provide a framework for understanding mechanisms in neurodegenerative disorders and for developing new intervention strategies. In this review we will discuss: the metabolites of sphingolipids that function as second messengers; and functional aberrations of the pathway resulting in Alzheimer's disease (AD) pathophysiology. Focusing on the central product of the sphingolipid pathway ceramide, we describ approaches to pharmacologically decrease ceramide levels in the brain and we argue on how the sphingolipid pathway may represent a new framework for developing novel intervention strategies in AD. We also highlight the possible use of clinical and non-clinical drugs to modulate the sphingolipid pathway and sphingolipid-related biological cascades.
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10
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Isokawa M, Sassa T, Hattori S, Miyakawa T, Kihara A. Reduced chain length in myelin sphingolipids and poorer motor coordination in mice deficient in the fatty acid elongase Elovl1. FASEB Bioadv 2019; 1:747-759. [PMID: 32123819 PMCID: PMC6996318 DOI: 10.1096/fba.2019-00067] [Citation(s) in RCA: 16] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/14/2019] [Revised: 08/14/2019] [Accepted: 10/30/2019] [Indexed: 11/23/2022] Open
Abstract
Very-long-chain fatty acids, with a chain length of >C20, are abundant in myelin sphingolipids. Recently, a de novo mutation in the ELOVL1 gene, which encodes fatty acid elongase, was identified in patients with neurocutaneous disorders involving skin ichthyosis and multiple neurological abnormalities, including hypomyelination, spastic paraplegia, and high-frequency deafness. However, the consequences of ELOVL1 deficiency for lipid composition and detailed pathological changes in the brain remain unclear. Here, we analyzed Elovl1 mutant mice as a model of human ELOVL1 deficiency. The mice exhibited a decreased postnatal survival rate, and some died of startle epilepsy. The acyl chain length of sphingolipids such as galactosylceramides, sulfatides, sphingomyelins, and ceramides in the brains of these mice was markedly shortened. Moreover, the mice exhibited reduced levels of galactosylceramides, which are important for myelin formation and stability. Electron microscope analysis of the corpus callosum in Elovl1 mutant mice revealed modest hypomyelination, especially in large-diameter axons. Furthermore, behavioral testing of the mice revealed deficits such as poorer motor coordination and reduced acoustic startle response to high-intensity stimulus. These findings provide clues to the molecular mechanism of the neurological symptoms of patients with the ELOVL1 mutation.
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Affiliation(s)
- Masashi Isokawa
- Laboratory of BiochemistryFaculty of Pharmaceutical SciencesHokkaido UniversitySapporoJapan
| | - Takayuki Sassa
- Laboratory of BiochemistryFaculty of Pharmaceutical SciencesHokkaido UniversitySapporoJapan
| | - Satoko Hattori
- Division of Systems Medical ScienceInstitute for Comprehensive Medical ScienceFujita Health UniversityToyoakeJapan
| | - Tsuyoshi Miyakawa
- Division of Systems Medical ScienceInstitute for Comprehensive Medical ScienceFujita Health UniversityToyoakeJapan
| | - Akio Kihara
- Laboratory of BiochemistryFaculty of Pharmaceutical SciencesHokkaido UniversitySapporoJapan
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Abstract
Long chain base (LCB) is a unique building block found in sphingolipids. The initial step of LCB biosynthesis stems from serine:palmitoyl-CoA transferase enzyme, producing 3-ketodihydrosphingosine with multiple regulatory proteins including small subunit SPT a/b and orosomucoid-like protein1-3. 3-Ketodihydrosphingosine reductase and sphingolipid Δ4-desaturase, both of them poorly characterized mammalian enzymes, play key roles for neurological homeostasis based on their pathogenic mutation in humans. Ceramide synthase in mammals has six isoforms with distinct phenotype in each knockout mouse. In plants and fungi, sphingolipids also contain phytosphingosine due to sphingolipid C4-hydroxylase. In contrast to previous notion that dietary intake might be its major route in animals, emerging evidences suggested that phytosphingosine biosynthesis does occur in some tissues such as the skin by mammalian C4-hydroxylase activity of the DEGS2 gene. This short review summarizes LCB biosynthesis with their associating metabolic pathways in animals, plants and fungi. Sphingolipid is a group of lipids that contains a unique building block known as long chain base (LCB). LCB is susceptible to various biosynthetic reactions such as unsaturation, hydroxylation and methylation. A failure of these enzymatic reactions leads to the pathogenesis in humans with an elevation of LCB-derived specific biomarkers. Herein, we summarized emerging evidences in mammalian LCB biosynthesis in sphingolipids. Some unique metabolic pathways in plants and fungi were also discussed.
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Ceramide Domains in Health and Disease: A Biophysical Perspective. ADVANCES IN EXPERIMENTAL MEDICINE AND BIOLOGY 2019; 1159:79-108. [DOI: 10.1007/978-3-030-21162-2_6] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/12/2022]
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13
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Garić D, De Sanctis JB, Shah J, Dumut DC, Radzioch D. Biochemistry of very-long-chain and long-chain ceramides in cystic fibrosis and other diseases: The importance of side chain. Prog Lipid Res 2019:100998. [PMID: 31445070 DOI: 10.1016/j.plipres.2019.100998] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/25/2019] [Revised: 03/01/2019] [Accepted: 03/10/2019] [Indexed: 12/18/2022]
Abstract
Ceramides, the principal building blocks of all sphingolipids, have attracted the attention of many scientists around the world interested in developing treatments for cystic fibrosis, the most common genetic disease of Caucasians. Many years of fruitful research in this field have produced some fundamentally important, yet controversial results. Here, we aimed to summarize the current knowledge on the role of long- and very-long- chain ceramides, the most abundant species of ceramides in animal cells, in cystic fibrosis and other diseases. We also aim to explain the importance of the length of their side chain in the context of stability of transmembrane proteins through a concise synthesis of their biophysical chemistry, cell biology, and physiology. This review also addresses several remaining riddles in this field. Finally, we discuss the technical challenges associated with the analysis and quantification of ceramides. We provide the evaluation of the antibodies used for ceramide quantification and we demonstrate their lack of specificity. Results and discussion presented here will be of interest to anyone studying these enigmatic lipids.
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Affiliation(s)
- Dušan Garić
- Department of Human Genetics, McGill University, Montreal, QC, Canada
| | - Juan B De Sanctis
- Institute of Molecular and Translational Medicine, Faculty of Medicine and Dentistry, Palacky University, Olomouc, Czech Republic
| | - Juhi Shah
- Department of Pharmacology and Experimental Therapeutics, McGill University, Montreal, QC, Canada
| | - Daciana Catalina Dumut
- Department of Medicine, Division of Experimental Medicine, McGill University, Montreal, QC, Canada
| | - Danuta Radzioch
- Department of Human Genetics, McGill University, Montreal, QC, Canada; Institute of Molecular and Translational Medicine, Faculty of Medicine and Dentistry, Palacky University, Olomouc, Czech Republic; Department of Medicine, Division of Experimental Medicine, McGill University, Montreal, QC, Canada.
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14
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Brachtendorf S, El-Hindi K, Grösch S. WITHDRAWN: Ceramide synthases in cancer therapy and chemoresistance. Prog Lipid Res 2019:100992. [PMID: 31442523 DOI: 10.1016/j.plipres.2019.100992] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/05/2019] [Revised: 04/02/2019] [Accepted: 04/02/2019] [Indexed: 10/26/2022]
Affiliation(s)
- Sebastian Brachtendorf
- Institute of Clinical Pharmacology, Faculty of Medicine, Goethe University Frankfurt, Theodor-Stern Kai 7, Frankfurt 60590, Germany
| | - Khadija El-Hindi
- Institute of Clinical Pharmacology, Faculty of Medicine, Goethe University Frankfurt, Theodor-Stern Kai 7, Frankfurt 60590, Germany
| | - Sabine Grösch
- Institute of Clinical Pharmacology, Faculty of Medicine, Goethe University Frankfurt, Theodor-Stern Kai 7, Frankfurt 60590, Germany
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15
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Brachtendorf S, El-Hindi K, Grösch S. Ceramide synthases in cancer therapy and chemoresistance. Prog Lipid Res 2019; 74:160-185. [DOI: 10.1016/j.plipres.2019.04.002] [Citation(s) in RCA: 35] [Impact Index Per Article: 7.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/05/2019] [Revised: 04/02/2019] [Accepted: 04/02/2019] [Indexed: 12/24/2022]
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16
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Garić D, De Sanctis JB, Shah J, Dumut DC, Radzioch D. Biochemistry of very-long-chain and long-chain ceramides in cystic fibrosis and other diseases: The importance of side chain. Prog Lipid Res 2019; 74:130-144. [PMID: 30876862 DOI: 10.1016/j.plipres.2019.03.001] [Citation(s) in RCA: 17] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/25/2019] [Revised: 03/01/2019] [Accepted: 03/10/2019] [Indexed: 12/19/2022]
Abstract
Ceramides, the principal building blocks of all sphingolipids, have attracted the attention of many scientists around the world interested in developing treatments for cystic fibrosis, the most common genetic disease of Caucasians. Many years of fruitful research in this field have produced some fundamentally important, yet controversial results. Here, we aimed to summarize the current knowledge on the role of long- and very-long- chain ceramides, the most abundant species of ceramides in animal cells, in cystic fibrosis and other diseases. We also aim to explain the importance of the length of their side chain in the context of stability of transmembrane proteins through a concise synthesis of their biophysical chemistry, cell biology, and physiology. This review also addresses several remaining riddles in this field. Finally, we discuss the technical challenges associated with the analysis and quantification of ceramides. We provide the evaluation of the antibodies used for ceramide quantification and we demonstrate their lack of specificity. Results and discussion presented here will be of interest to anyone studying these enigmatic lipids.
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Affiliation(s)
- Dušan Garić
- Department of Human Genetics, McGill University, Montreal, QC, Canada
| | - Juan B De Sanctis
- Institute of Molecular and Translational Medicine, Faculty of Medicine and Dentistry, Palacky University, Olomouc, Czech Republic
| | - Juhi Shah
- Department of Pharmacology and Experimental Therapeutics, McGill University, Montreal, QC, Canada
| | - Daciana Catalina Dumut
- Department of Medicine, Division of Experimental Medicine, McGill University, Montreal, QC, Canada
| | - Danuta Radzioch
- Department of Human Genetics, McGill University, Montreal, QC, Canada; Institute of Molecular and Translational Medicine, Faculty of Medicine and Dentistry, Palacky University, Olomouc, Czech Republic; Department of Medicine, Division of Experimental Medicine, McGill University, Montreal, QC, Canada.
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17
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Zelnik ID, Rozman B, Rosenfeld-Gur E, Ben-Dor S, Futerman AH. A Stroll Down the CerS Lane. ADVANCES IN EXPERIMENTAL MEDICINE AND BIOLOGY 2019; 1159:49-63. [DOI: 10.1007/978-3-030-21162-2_4] [Citation(s) in RCA: 18] [Impact Index Per Article: 3.6] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/05/2023]
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18
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Albeituni S, Stiban J. Roles of Ceramides and Other Sphingolipids in Immune Cell Function and Inflammation. ADVANCES IN EXPERIMENTAL MEDICINE AND BIOLOGY 2019; 1161:169-191. [PMID: 31562630 DOI: 10.1007/978-3-030-21735-8_15] [Citation(s) in RCA: 63] [Impact Index Per Article: 12.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/13/2022]
Abstract
Ceramides are bioactive sphingolipids that support the structure of the plasma membrane and mediate numerous cell-signaling events in eukaryotic cells. The finding that ceramides act as second messengers transducing cellular signals has attracted substantial attention in several fields of Biology. Since all cells contain lipid plasma membranes, the impact of various ceramides, ceramide synthases, ceramide metabolites, and other sphingolipids has been implicated in a vast range of cellular functions including, migration, proliferation, response to external stimuli, and death. The roles of lipids in these functions widely differ among the diverse cell types. Herein, we discuss the roles of ceramides and other sphingolipids in mediating the function of various immune cells; particularly dendritic cells, neutrophils, and macrophages. In addition, we highlight the main studies describing effects of ceramides in inflammation, specifically in various inflammatory settings including insulin resistance, graft-versus-host disease, immune suppression in cancer, multiple sclerosis, and inflammatory bowel disease.
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Affiliation(s)
- Sabrin Albeituni
- Department of Oncology, St. Jude Children's Research Hospital, Memphis, TN, USA
| | - Johnny Stiban
- Department of Biology and Biochemistry, Birzeit University, West Bank, Palestine.
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19
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Wang G, Bieberich E. Sphingolipids in neurodegeneration (with focus on ceramide and S1P). Adv Biol Regul 2018; 70:51-64. [PMID: 30287225 PMCID: PMC6251739 DOI: 10.1016/j.jbior.2018.09.013] [Citation(s) in RCA: 58] [Impact Index Per Article: 9.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/06/2018] [Revised: 09/20/2018] [Accepted: 09/21/2018] [Indexed: 04/14/2023]
Abstract
For many decades, research on sphingolipids associated with neurodegenerative disease focused on alterations in glycosphingolipids, particularly glycosylceramides (cerebrosides), sulfatides, and gangliosides. This seemed quite natural since many of these glycolipids are constituents of myelin and accumulated in lipid storage diseases (sphingolipidoses) resulting from enzyme deficiencies in glycolipid metabolism. With the advent of recognizing ceramide and its derivative, sphingosine-1-phosphate (S1P), as key players in lipid cell signaling and regulation of cell death and survival, research focus shifted toward these two sphingolipids. Ceramide and S1P are invoked in a plethora of cell biological processes participating in neurodegeneration such as ER stress, autophagy, dysregulation of protein and lipid transport, exosome secretion and neurotoxic protein spreading, neuroinflammation, and mitochondrial dysfunction. Hence, it is timely to discuss various functions of ceramide and S1P in neurodegenerative disease and to define sphingolipid metabolism and cell signaling pathways as potential targets for therapy.
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Affiliation(s)
- Guanghu Wang
- Department of Physiology, University of Kentucky, Lexington, KY, USA
| | - Erhard Bieberich
- Department of Physiology, University of Kentucky, Lexington, KY, USA.
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20
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Bieberich E. Sphingolipids and lipid rafts: Novel concepts and methods of analysis. Chem Phys Lipids 2018; 216:114-131. [PMID: 30194926 PMCID: PMC6196108 DOI: 10.1016/j.chemphyslip.2018.08.003] [Citation(s) in RCA: 133] [Impact Index Per Article: 22.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/19/2018] [Revised: 08/20/2018] [Accepted: 08/25/2018] [Indexed: 12/12/2022]
Abstract
About twenty years ago, the functional lipid raft model of the plasma membrane was published. It took into account decades of research showing that cellular membranes are not just homogenous mixtures of lipids and proteins. Lateral anisotropy leads to assembly of membrane domains with specific lipid and protein composition regulating vesicular traffic, cell polarity, and cell signaling pathways in a plethora of biological processes. However, what appeared to be a clearly defined entity of clustered raft lipids and proteins became increasingly fluid over the years, and many of the fundamental questions about biogenesis and structure of lipid rafts remained unanswered. Experimental obstacles in visualizing lipids and their interactions hampered progress in understanding just how big rafts are, where and when they are formed, and with which proteins raft lipids interact. In recent years, we have begun to answer some of these questions and sphingolipids may take center stage in re-defining the meaning and functional significance of lipid rafts. In addition to the archetypical cholesterol-sphingomyelin raft with liquid ordered (Lo) phase and the liquid-disordered (Ld) non-raft regions of cellular membranes, a third type of microdomains termed ceramide-rich platforms (CRPs) with gel-like structure has been identified. CRPs are "ceramide rafts" that may offer some fresh view on the membrane mesostructure and answer several critical questions for our understanding of lipid rafts.
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Affiliation(s)
- Erhard Bieberich
- Department of Physiology at the University of Kentucky, Lexington, KY, United States.
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21
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Bialik S, Dasari SK, Kimchi A. Autophagy-dependent cell death – where, how and why a cell eats itself to death. J Cell Sci 2018; 131:131/18/jcs215152. [DOI: 10.1242/jcs.215152] [Citation(s) in RCA: 170] [Impact Index Per Article: 28.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/13/2022] Open
Abstract
ABSTRACT
Autophagy as a means of cell killing was first advanced by Clark's phenotypic description of ‘Type II autophagic cell death’ in 1990. However, this phenomenon later came into question, because the presence of autophagosomes in dying cells does not necessarily signify that autophagy is the cause of demise, but rather may reflect the efforts of the cell to prevent it. Resolution of this issue comes from a more careful definition of autophagy-dependent cell death (ADCD) as a regulated cell death that is shown experimentally to require different components of the autophagy machinery without involvement of alternative cell death pathways. Following these strict criteria, ADCD has been validated in both lower model organisms and mammalian cells, highlighting its importance for developmental and pathophysiological cell death. Recently, researchers have defined additional morphological criteria that characterize ADCD and begun to explore how the established, well-studied autophagy pathway is subverted from a survival to a death function. This Review explores validated models of ADCD and focuses on the current understanding of the mechanisms by which autophagy can kill a cell.
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Affiliation(s)
- Shani Bialik
- Department of Molecular Genetics, Weizmann Institute of Science, Rehovot 76100, Israel
| | - Santosh K. Dasari
- Department of Molecular Genetics, Weizmann Institute of Science, Rehovot 76100, Israel
| | - Adi Kimchi
- Department of Molecular Genetics, Weizmann Institute of Science, Rehovot 76100, Israel
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22
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Metcalfe LK, Smith GC, Turner N. Defining lipid mediators of insulin resistance - controversies and challenges. J Mol Endocrinol 2018; 62:JME-18-0023. [PMID: 30068522 DOI: 10.1530/jme-18-0023] [Citation(s) in RCA: 17] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 01/23/2018] [Revised: 07/04/2018] [Accepted: 07/31/2018] [Indexed: 12/31/2022]
Abstract
Essential elements of all cells, lipids play important roles in energy production, signalling and as structural components. Despite these critical functions, excessive availability and intracellular accumulation of lipid is now recognised as a major factor contributing to many human diseases, including obesity and diabetes. In the context of these metabolic disorders, ectopic deposition of lipid has been proposed to have deleterious effects of insulin action. While this relationship has been recognised for some time now, there is currently no unifying mechanism to explain how lipids precipitate the development of insulin resistance. This review summarises the evidence linking specific lipid molecules to the induction of insulin resistance, describing some of the current controversies and challenges for future studies in this field.
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Affiliation(s)
- Louise K Metcalfe
- L Metcalfe, Department of Pharmacology, School of Medical Sciences, UNSW Australia, Kensington, Australia
| | - Greg C Smith
- G Smith, Department of Pharmacology, School of Medical Sciences, UNSW Australia, Kensington, Australia
| | - Nigel Turner
- N Turner, Department of Pharmacology, School of Medical Sciences, University of New South Wales, Sydney, Australia
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23
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Abstract
Exosomes are secreted extracellular vesicles (EVs) that carry micro RNAs and other factors to reprogram cancer cells and tissues affected by cancer. Exosomes are exchanged between cancer cells and other tissues, often to prepare a premetastatic niche, escape immune surveillance, or spread multidrug resistance. Only a few studies investigated the function of lipids in exosomes although their lipid composition is different from that of the secreting cells. Ceramide is one of the lipids critical for exosome formation, and it is also enriched in these EVs. New research suggests that lipids in the exosomal membrane may organize and transmit "mobile rafts" that turn exosomes into extracellular signalosomes spreading activation of cell signaling pathways in oncogenesis and metastasis. Ceramide may modulate the function of mobile rafts and their effect on these cell signaling pathways. The critical role of lipids and, in particular, ceramide for formation, secretion, and function of exosomes may lead to a radically new understanding of cancer biology and therapy.
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Affiliation(s)
- Ahmed Elsherbini
- Department of Physiology, University of Kentucky, Lexington, KY, United States
| | - Erhard Bieberich
- Department of Physiology, University of Kentucky, Lexington, KY, United States
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24
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Abstract
Ceramides are sphingolipids containing a sphingosine or a related base, to which a fatty acid is linked through an amide bond. When incorporated into a lipid bilayer, ceramides exhibit a number of properties not shared by almost any other membrane lipid: Ceramides ( a) are extremely hydrophobic and thus cannot exist in suspension in aqueous media; ( b) increase the molecular order (rigidity) of phospholipids in membranes; ( c) give rise to lateral phase separation and domain formation in phospholipid bilayers; ( d) possess a marked intrinsic negative curvature that facilitates formation of inverted hexagonal phases; ( e) make bilayers and cell membranes permeable to small and large (i.e., protein-size) solutes; and ( f) promote transmembrane (flip-flop) lipid motion. Unfortunately, there is hardly any link between the physical studies reviewed here and the mass of biological and clinical studies on the effects of ceramides in health and disease.
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Affiliation(s)
- Alicia Alonso
- Instituto Biofisika [University of the Basque Country and Spanish National Research Council (CSIC)], 48940 Leioa, Spain
- Department of Biochemistry and Molecular Biology, University of the Basque Country, 48940 Leioa, Spain;,
| | - Félix M. Goñi
- Instituto Biofisika [University of the Basque Country and Spanish National Research Council (CSIC)], 48940 Leioa, Spain
- Department of Biochemistry and Molecular Biology, University of the Basque Country, 48940 Leioa, Spain;,
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25
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Olsen ASB, Færgeman NJ. Sphingolipids: membrane microdomains in brain development, function and neurological diseases. Open Biol 2018; 7:rsob.170069. [PMID: 28566300 PMCID: PMC5451547 DOI: 10.1098/rsob.170069] [Citation(s) in RCA: 201] [Impact Index Per Article: 33.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/21/2017] [Accepted: 04/30/2017] [Indexed: 12/11/2022] Open
Abstract
Sphingolipids are highly enriched in the nervous system where they are pivotal constituents of the plasma membranes and are important for proper brain development and functions. Sphingolipids are not merely structural elements, but are also recognized as regulators of cellular events by their ability to form microdomains in the plasma membrane. The significance of such compartmentalization spans broadly from being involved in differentiation of neurons and synaptic transmission to neuronal–glial interactions and myelin stability. Thus, perturbations of the sphingolipid metabolism can lead to rearrangements in the plasma membrane, which has been linked to the development of various neurological diseases. Studying microdomains and their functions has for a long time been synonymous with studying the role of cholesterol. However, it is becoming increasingly clear that microdomains are very heterogeneous, which among others can be ascribed to the vast number of sphingolipids. In this review, we discuss the importance of microdomains with emphasis on sphingolipids in brain development and function as well as how disruption of the sphingolipid metabolism (and hence microdomains) contributes to the pathogenesis of several neurological diseases.
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Affiliation(s)
- Anne S B Olsen
- Villum Center for Bioanalytical Sciences, Department of Biochemistry and Molecular Biology, University of Southern Denmark, 5230 Odense M, Denmark
| | - Nils J Færgeman
- Villum Center for Bioanalytical Sciences, Department of Biochemistry and Molecular Biology, University of Southern Denmark, 5230 Odense M, Denmark
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26
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Abstract
Gangliosides are sialic acid containing glycosphingolipids, which are abundant in mammalian brain tissue. Several fatal human diseases are caused by defects in glycolipid metabolism. Defects in their degradation lead to an accumulation of metabolites upstream of the defective reactions, whereas defects in their biosynthesis lead to diverse problems in a large number of organs.Gangliosides are primarily positioned with their ceramide anchor in the neuronal plasma membrane and the glycan head group exposed on the cell surface. Their biosynthesis starts in the endoplasmic reticulum with the formation of the ceramide anchor, followed by sequential glycosylation reactions, mainly at the luminal surface of Golgi and TGN membranes, a combinatorial process, which is catalyzed by often promiscuous membrane-bound glycosyltransferases.Thereafter, the gangliosides are transported to the plasma membrane by exocytotic membrane flow. After endocytosis, they are degraded within the endolysosomal compartments by a complex machinery of degrading enzymes, lipid-binding activator proteins, and negatively charged lipids.
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Affiliation(s)
- Bernadette Breiden
- LIMES Institute, Membrane Biology & Lipid Biochemistry Unit, Kekulé-Institut für Organische Chemie und Biochemie, Universität Bonn, Bonn, Germany
| | - Konrad Sandhoff
- LIMES Institute, Membrane Biology & Lipid Biochemistry Unit, Kekulé-Institut für Organische Chemie und Biochemie, Universität Bonn, Bonn, Germany.
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27
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Saroha A, Pewzner-Jung Y, Ferreira NS, Sharma P, Jouan Y, Kelly SL, Feldmesser E, Merrill AH, Trottein F, Paget C, Lang KS, Futerman AH. Critical Role for Very-Long Chain Sphingolipids in Invariant Natural Killer T Cell Development and Homeostasis. Front Immunol 2017; 8:1386. [PMID: 29163475 PMCID: PMC5672022 DOI: 10.3389/fimmu.2017.01386] [Citation(s) in RCA: 15] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [Key Words] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/28/2017] [Accepted: 10/09/2017] [Indexed: 12/14/2022] Open
Abstract
The role of sphingolipids (SLs) in the immune system has come under increasing scrutiny recently due to the emerging contributions that these important membrane components play in regulating a variety of immunological processes. The acyl chain length of SLs appears particularly critical in determining SL function. Here, we show a role for very-long acyl chain SLs (VLC-SLs) in invariant natural killer T (iNKT) cell maturation in the thymus and homeostasis in the liver. Ceramide synthase 2-null mice, which lack VLC-SLs, were susceptible to a hepatotropic strain of lymphocytic choriomeningitis virus, which is due to a reduction in the number of iNKT cells. Bone marrow chimera experiments indicated that hematopoietic-derived VLC-SLs are essential for maturation of iNKT cells in the thymus, whereas parenchymal-derived VLC-SLs are crucial for iNKT cell survival and maintenance in the liver. Our findings suggest a critical role for VLC-SL in iNKT cell physiology.
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Affiliation(s)
- Ashish Saroha
- Department of Biomolecular Sciences, Weizmann Institute of Science, Rehovot, Israel
| | - Yael Pewzner-Jung
- Department of Biomolecular Sciences, Weizmann Institute of Science, Rehovot, Israel
| | - Natalia S Ferreira
- Department of Biomolecular Sciences, Weizmann Institute of Science, Rehovot, Israel
| | - Piyush Sharma
- Medical Faculty, Institute of Immunology, University Duisburg-Essen, Essen, Germany
| | - Youenn Jouan
- INSERM U1100, Centre d'Etude des Pathologies Respiratoires, Faculté de Médecine, Tours, France
| | - Samuel L Kelly
- School of Biology and Petit Institute for Bioengineering and Bioscience, Georgia Institute of Technology, Atlanta, GA, United States
| | - Ester Feldmesser
- Life Science Core Facilities, Weizmann Institute of Science, Rehovot, Israel
| | - Alfred H Merrill
- School of Biology and Petit Institute for Bioengineering and Bioscience, Georgia Institute of Technology, Atlanta, GA, United States
| | - François Trottein
- Centre d'Infection et d'Immunité de Lille, INSERM U1019, CNRS UMR 8204, University of Lille, CHU Lille- Institut Pasteur de Lille, Lille, France
| | - Christophe Paget
- INSERM U1100, Centre d'Etude des Pathologies Respiratoires, Faculté de Médecine, Tours, France.,Centre d'Infection et d'Immunité de Lille, INSERM U1019, CNRS UMR 8204, University of Lille, CHU Lille- Institut Pasteur de Lille, Lille, France
| | - Karl S Lang
- Medical Faculty, Institute of Immunology, University Duisburg-Essen, Essen, Germany
| | - Anthony H Futerman
- Department of Biomolecular Sciences, Weizmann Institute of Science, Rehovot, Israel
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28
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Lee WK, Kolesnick RN. Sphingolipid abnormalities in cancer multidrug resistance: Chicken or egg? Cell Signal 2017; 38:134-145. [PMID: 28687494 DOI: 10.1016/j.cellsig.2017.06.017] [Citation(s) in RCA: 30] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/08/2017] [Revised: 06/25/2017] [Accepted: 06/25/2017] [Indexed: 12/12/2022]
Abstract
The cancer multidrug resistance (MDR) phenotype encompasses a myriad of molecular, genetic and cellular alterations resulting from progressive oncogenic transformation and selection. Drug efflux transporters, in particular the MDR P-glycoprotein ABCB1, play an important role in MDR but cannot confer the complete phenotype alone indicating parallel alterations are prerequisite. Sphingolipids are essential constituents of lipid raft domains and directly participate in functionalization of transmembrane proteins, including providing an optimal lipid microenvironment for multidrug transporters, and are also perturbed in cancer. Here we postulate that increased sphingomyelin content, developing early in some cancers, recruits and functionalizes plasma membrane ABCB1 conferring a state of partial MDR, which is completed by glycosphingolipid disturbance and the appearance of intracellular vesicular ABCB1. In this review, the independent and interdependent roles of sphingolipid alterations and ABCB1 upregulation during the transformation process and resultant conferment of partial and complete MDR phenotypes are discussed.
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Affiliation(s)
- Wing-Kee Lee
- Laboratory of Signal Transduction, Sloan Kettering Institute for Cancer Research, Memorial Sloan-Kettering Cancer Center, New York, United States; Institute for Physiology, Pathophysiology and Toxicology, Centre for Biomedical Education and Research (ZBAF), Witten/Herdecke University, Witten, Germany.
| | - Richard N Kolesnick
- Laboratory of Signal Transduction, Sloan Kettering Institute for Cancer Research, Memorial Sloan-Kettering Cancer Center, New York, United States
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29
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Rodriguez-Cuenca S, Pellegrinelli V, Campbell M, Oresic M, Vidal-Puig A. Sphingolipids and glycerophospholipids - The "ying and yang" of lipotoxicity in metabolic diseases. Prog Lipid Res 2017; 66:14-29. [PMID: 28104532 DOI: 10.1016/j.plipres.2017.01.002] [Citation(s) in RCA: 94] [Impact Index Per Article: 13.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/16/2016] [Revised: 11/30/2016] [Accepted: 01/05/2017] [Indexed: 12/14/2022]
Abstract
Sphingolipids in general and ceramides in particular, contribute to pathophysiological mechanisms by modifying signalling and metabolic pathways. Here, we present the available evidence for a bidirectional homeostatic crosstalk between sphingolipids and glycerophospholipids, whose dysregulation contributes to lipotoxicity induced metabolic stress. The initial evidence for this crosstalk originates from simulated models designed to investigate the biophysical properties of sphingolipids in plasma membrane representations. In this review, we reinterpret some of the original findings and conceptualise them as a sort of "ying/yang" interaction model of opposed/complementary forces, which is consistent with the current knowledge of lipid homeostasis and pathophysiology. We also propose that the dysregulation of the balance between sphingolipids and glycerophospholipids results in a lipotoxic insult relevant in the pathophysiology of common metabolic diseases, typically characterised by their increased ceramide/sphingosine pools.
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Affiliation(s)
- S Rodriguez-Cuenca
- Metabolic Research Laboratories, Wellcome Trust MRC Institute of Metabolic Science, Addenbrooke's Hospital, University of Cambridge. Cambridge, UK.
| | - V Pellegrinelli
- Metabolic Research Laboratories, Wellcome Trust MRC Institute of Metabolic Science, Addenbrooke's Hospital, University of Cambridge. Cambridge, UK
| | - M Campbell
- Metabolic Research Laboratories, Wellcome Trust MRC Institute of Metabolic Science, Addenbrooke's Hospital, University of Cambridge. Cambridge, UK
| | - M Oresic
- Turku Centre for Biotechnology, University of Turku and Åbo Akademi University, FI -20520 Turku, Finland
| | - A Vidal-Puig
- Metabolic Research Laboratories, Wellcome Trust MRC Institute of Metabolic Science, Addenbrooke's Hospital, University of Cambridge. Cambridge, UK; Wellcome Trust Sanger Institute, Hinxton, UK.
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30
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Volpert G, Ben-Dor S, Tarcic O, Duan J, Saada A, Merrill AH, Pewzner-Jung Y, Futerman AH. Oxidative stress elicited by modifying the ceramide acyl chain length reduces the rate of clathrin-mediated endocytosis. J Cell Sci 2017; 130:1486-1493. [PMID: 28280117 DOI: 10.1242/jcs.199968] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/21/2016] [Accepted: 02/28/2017] [Indexed: 12/11/2022] Open
Abstract
Sphingolipids modulate clathrin-mediated endocytosis (CME) by altering the biophysical properties of membranes. We now examine CME in astrocytes cultured from ceramide synthase 2 (CerS2) null mice, which have an altered sphingolipid acyl chain composition. The rate of endocytosis of low-density lipoprotein and transferrin, which are internalized via CME, was reduced in CerS2 null astrocytes, although the rate of caveolin-mediated endocytosis was unaltered. Levels of clathrin heavy chain were increased, which was due to decreased levels of Hsc70 (also known as HSPA8), a protein involved in clathrin uncoating. Hsc70 levels were decreased because of lower levels of binding of Sp1 to position -68 in the Hsc70 promoter. Levels of Sp1 were downregulated due to oxidative stress, which was elevated fourfold in CerS2 null astrocytes. Furthermore, induction of oxidative stress in wild-type astrocytes decreased the rate of CME, whereas amelioration of oxidative stress in CerS2 null astrocytes reversed the decrease. Our data are consistent with the notion that sphingolipids not only change membrane biophysical properties but also that changes in their composition can result in downstream effects that indirectly impinge upon a number of cellular pathways, such as CME.
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Affiliation(s)
- Giora Volpert
- Department of Biomolecular Sciences, Weizmann Institute of Science, Rehovot 76100, Israel
| | - Shifra Ben-Dor
- Department of Biological Services, Weizmann Institute of Science, Rehovot 76100, Israel
| | - Ohad Tarcic
- Department of Molecular Cell Biology, Weizmann Institute of Science, Rehovot 76100, Israel
| | - Jingjing Duan
- School of Biology and Petit Institute for Bioengineering and Bioscience, Georgia Institute of Technology, Atlanta, GA 30332-0230, USA
| | - Ann Saada
- Monique and Jacques Roboh Department of Genetic Research, Hadassah-Hebrew University Hospital, Jerusalem 91120, Israel.,The Department of Genetic and Metabolic Diseases, Hadassah-Hebrew University Hospital, Jerusalem 91120, Israel
| | - Alfred H Merrill
- School of Biology and Petit Institute for Bioengineering and Bioscience, Georgia Institute of Technology, Atlanta, GA 30332-0230, USA
| | - Yael Pewzner-Jung
- Department of Biomolecular Sciences, Weizmann Institute of Science, Rehovot 76100, Israel
| | - Anthony H Futerman
- Department of Biomolecular Sciences, Weizmann Institute of Science, Rehovot 76100, Israel
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31
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Abstract
The sphingolipid family of lipids modulate several cellular processes, including proliferation, cell cycle regulation, inflammatory signaling pathways, and cell death. Several members of the sphingolipid pathway have opposing functions and thus imbalances in sphingolipid metabolism result in deregulated cellular processes, which cause or contribute to diseases and disorders in humans. A key cellular process regulated by sphingolipids is apoptosis, or programmed cell death. Sphingolipids play an important role in both extrinsic and intrinsic apoptotic pathways depending on the stimuli, cell type and cellular response to the stress. During mitochondrial-mediated apoptosis, multiple pathways converge on mitochondria and induce mitochondrial outer membrane permeabilization (MOMP). MOMP results in the release of intermembrane space proteins such as cytochrome c and Apaf1 into the cytosol where they activate the caspases and DNases that execute cell death. The precise molecular components of the pore(s) responsible for MOMP are unknown, but sphingolipids are thought to play a role. Here, we review evidence for a role of sphingolipids in the induction of mitochondrial-mediated apoptosis with a focus on potential underlying molecular mechanisms by which altered sphingolipid metabolism indirectly or directly induce MOMP. Data available on these mechanisms is reviewed, and the focus and limitations of previous and current studies are discussed to present important unanswered questions and potential future directions.
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Affiliation(s)
- Gauri A Patwardhan
- Department of Pharmacology and Toxicology, University of Louisville, Louisville, KY, 40202, USA
| | - Levi J Beverly
- Department of Pharmacology and Toxicology, University of Louisville, Louisville, KY, 40202, USA.,Department of Medicine, University of Louisville, Louisville, KY, 40202, USA.,James Graham Brown Cancer Center, University of Louisville, 505 South Hancock Street, Clinical and Translational Research Building, Room 203, Louisville, KY, 40202, USA
| | - Leah J Siskind
- Department of Pharmacology and Toxicology, University of Louisville, Louisville, KY, 40202, USA. .,James Graham Brown Cancer Center, University of Louisville, 505 South Hancock Street, Clinical and Translational Research Building, Room 203, Louisville, KY, 40202, USA.
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1-Deoxysphingolipid-induced neurotoxicity involves N-methyl-d-aspartate receptor signaling. Neuropharmacology 2016; 110:211-222. [DOI: 10.1016/j.neuropharm.2016.03.033] [Citation(s) in RCA: 26] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/24/2015] [Revised: 03/11/2016] [Accepted: 03/22/2016] [Indexed: 11/17/2022]
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Increased Plasma Levels of Select Deoxy-ceramide and Ceramide Species are Associated with Increased Odds of Diabetic Neuropathy in Type 1 Diabetes: A Pilot Study. Neuromolecular Med 2016; 19:46-56. [PMID: 27388466 DOI: 10.1007/s12017-016-8423-9] [Citation(s) in RCA: 17] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/30/2016] [Accepted: 06/30/2016] [Indexed: 12/14/2022]
Abstract
Plasma deoxy-sphingoid bases are elevated in type 2 diabetes patients and correlate with the stage of diabetic distal sensorimotor polyneuropathy; however, associations between deoxy-sphingolipids (DSL) and neuropathy in type 1 diabetes have not been examined. The primary aim of this exploratory pilot study was to assess the associations between multiple sphingolipid species including DSL and free amino acids and the presence of symptomatic neuropathy in a DCCT/EDIC type 1 diabetes subcohort. Using mass spectroscopy, plasma levels of DSL and free amino acids in DCCT/EDIC type 1 diabetes participants (n = 80), with and without symptoms of neuropathy, were investigated. Patient-determined neuropathy was based on 15-item self-administered questionnaire (Michigan Neuropathy Screening Instrument) developed to assess distal symmetrical peripheral neuropathy in diabetes. Patients who scored ≥4, or reported inability to sense their feet during walking or to distinguish hot from cold water while bathing were considered neuropathic. Plasma levels of ceramide, sphingomyelin, hexosyl- and lactosylceramide species, and amino acids were measured and analyzed relative to neuropathy status in the patient. Deoxy-C24-ceramide, C24- and C26-ceramide were higher in patients with neuropathy than those without neuropathy. Cysteine was higher in patients with neuropathy. No differences in other sphingolipids or amino acids were detected. The covariate-adjusted Odds Ratios of positive patient-reported neuropathy was associated with increased levels of deoxy-C24-, and deoxy-C24:1-ceramide; C22-, C24-, and C26-ceramide; and cysteine. Plasma deoxy-ceramide and ceramide species may have potential diagnostic and prognostic significance in diabetic neuropathy.
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Glycosphingolipid analysis in a naturally occurring ovine model of acute neuronopathic Gaucher disease. Neurobiol Dis 2016; 91:143-54. [DOI: 10.1016/j.nbd.2016.03.011] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/13/2015] [Revised: 01/18/2016] [Accepted: 03/10/2016] [Indexed: 01/06/2023] Open
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Yoshizaki H, Ogiso H, Okazaki T, Kiyokawa E. Comparative lipid analysis in the normal and cancerous organoids of MDCK cells. J Biochem 2016; 159:573-84. [PMID: 26783265 DOI: 10.1093/jb/mvw001] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/07/2015] [Accepted: 12/06/2015] [Indexed: 11/14/2022] Open
Abstract
Epithelial organs are made of a well-polarized monolayer of epithelial cells, and their morphology is maintained strictly for their proper functioning. The roles of lipids are not only to generate the membrane, but also to provide the specific domains for signal transduction, or to transmit signals as second messengers. By using a liquid chromatography-electrospray ionization mass spectrometry (LC-MS)/MS method, we here analyzed sphingolipids in MDCK cysts under various conditions. Our result showed that, compared to the three-dimensional cyst, the two-dimensional MDCK sheet is relatively enriched in sphingolipids. During cystogenesis, the contents of sphingomyelin (SM) and lactocylceramide (LacCer)-but, none those of ceramide, hexocylceramide, or GM3-are altered depending on their acyl chains. While the total SM is decreased more efficiently by SMS-1 knockdown than by SMS-2 knockdown, depletion of SMS-2, but not SMS-1, inhibits cyst growth. Finally upon the switching on of activated K-Ras expression which induces luminal cell filling, ceramide and LacCer are increased. Our parallel examinations of the microarray data for mRNA of sphingolipid metabolic enzymes failed to fully explain the remodelling of the sphingolipids of MDCK cysts. However, these results should be useful to investigate the cell-type- and structure-specific lipid metabolism.
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Affiliation(s)
| | - Hideo Ogiso
- Department of Hematology/Immunology, Kanazawa Medical University, Ishikawa 920-0293, Japan
| | - Toshiro Okazaki
- Department of Hematology/Immunology, Kanazawa Medical University, Ishikawa 920-0293, Japan
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Choi S, Kim JA, Kim TH, Li H, Shin K, Lee Y, Oh S, Pewzner‐Jung Y, Futerman AH, Suh SH. Altering sphingolipid composition with aging induces contractile dysfunction of gastric smooth muscle via K(Ca) 1.1 upregulation. Aging Cell 2015; 14:982-94. [PMID: 26288989 PMCID: PMC4693452 DOI: 10.1111/acel.12388] [Citation(s) in RCA: 18] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 07/19/2015] [Indexed: 01/16/2023] Open
Abstract
KCa1.1 regulates smooth muscle contractility by modulating membrane potential, and age‐associated changes in KCa1.1 expression may contribute to the development of motility disorders of the gastrointestinal tract. Sphingolipids (SLs) are important structural components of cellular membranes whose altered composition may affect KCa1.1 expression. Thus, in this study, we examined whether altered SL composition due to aging may affect the contractility of gastric smooth muscle (GSM). We studied changes in ceramide synthases (CerS) and SL levels in the GSM of mice of varying ages and compared them with those in young CerS2‐null mice. The levels of C16‐ and C18‐ceramides, sphinganine, sphingosine, and sphingosine 1‐phosphate were increased, and levels of C22, C24:1 and C24 ceramides were decreased in the GSM of both aged wild‐type and young CerS2‐null mice. The altered SL composition upregulated KCa1.1 and increased KCa1.1 currents, while no change was observed in KCa1.1 channel activity. The upregulation of KCa1.1 impaired intracellular Ca2+ mobilization and decreased phosphorylated myosin light chain levels, causing GSM contractile dysfunction. Additionally, phosphoinositide 3‐kinase, protein kinase Cζ, c‐Jun N‐terminal kinases, and nuclear factor kappa‐B were found to be involved in KCa1.1 upregulation. Our findings suggest that age‐associated changes in SL composition or CerS2 ablation upregulate KCa1.1 via the phosphoinositide 3‐kinase/protein kinase Cζ/c‐Jun N‐terminal kinases/nuclear factor kappa‐B‐mediated pathway and impair Ca2+ mobilization, which thereby induces the contractile dysfunction of GSM. CerS2‐null mice exhibited similar effects to aged wild‐type mice; therefore, CerS2‐null mouse models may be utilized for investigating the pathogenesis of aging‐associated motility disorders.
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Affiliation(s)
- Shinkyu Choi
- Department of Physiology Medical School Ewha Womans University Seoul Korea
| | - Ji Aee Kim
- Department of Physiology Medical School Ewha Womans University Seoul Korea
| | - Tae Hun Kim
- Department of Internal Medicine Medical School Ewha Womans University Seoul Korea
| | - Hai‐yan Li
- Department of Physiology Medical School Ewha Womans University Seoul Korea
| | - Kyong‐Oh Shin
- College of Pharmacy and MRC Chungbuk National University Chongju Korea
| | - Yong‐Moon Lee
- College of Pharmacy and MRC Chungbuk National University Chongju Korea
| | - Seikwan Oh
- Department of Molecular Medicine Medical School Ewha Womans University Seoul Korea
| | - Yael Pewzner‐Jung
- Department of Biological Chemistry Weizmann Institute of Science Rehovot Israel
| | - Anthony H. Futerman
- Department of Biological Chemistry Weizmann Institute of Science Rehovot Israel
| | - Suk Hyo Suh
- Department of Physiology Medical School Ewha Womans University Seoul Korea
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Ali M, Saroha A, Pewzner-Jung Y, Futerman AH. LPS-mediated septic shock is augmented in ceramide synthase 2 null mice due to elevated activity of TNFα-converting enzyme. FEBS Lett 2015; 589:2213-7. [PMID: 26183206 DOI: 10.1016/j.febslet.2015.06.045] [Citation(s) in RCA: 20] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/20/2015] [Revised: 06/10/2015] [Accepted: 06/30/2015] [Indexed: 12/21/2022]
Abstract
Tumor necrosis factor α (TNFα) is an inflammatory cytokine that plays an intimate role in septic shock. Injection of high levels of lipopolysaccharide induces septic shock and death in mice within 30 h, whereas ceramide synthase 2 (CerS2) null mice, defective in the synthesis of very-long acyl chain ceramides, die within ∼10 h. The augmented rate of death of CerS2 null mice is due to elevated levels of TNFα secretion as a result of enhanced activity of TNFα-converting enzyme (TACE). We discuss the relationship between the sphingolipid acyl chain length and TACE activity and the relevance of this data to septic shock.
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Affiliation(s)
- Mohammad Ali
- Department of Biological Chemistry, Weizmann Institute of Science, Rehovot 76100, Israel
| | - Ashish Saroha
- Department of Biological Chemistry, Weizmann Institute of Science, Rehovot 76100, Israel
| | - Yael Pewzner-Jung
- Department of Biological Chemistry, Weizmann Institute of Science, Rehovot 76100, Israel
| | - Anthony H Futerman
- Department of Biological Chemistry, Weizmann Institute of Science, Rehovot 76100, Israel.
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Orchestration of membrane receptor signaling by membrane lipids. Biochimie 2015; 113:111-24. [DOI: 10.1016/j.biochi.2015.04.005] [Citation(s) in RCA: 23] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/03/2014] [Accepted: 04/05/2015] [Indexed: 12/20/2022]
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Hepatic fatty acid uptake is regulated by the sphingolipid acyl chain length. Biochim Biophys Acta Mol Cell Biol Lipids 2015; 1841:1754-66. [PMID: 25241943 DOI: 10.1016/j.bbalip.2014.09.009] [Citation(s) in RCA: 40] [Impact Index Per Article: 4.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/10/2014] [Revised: 09/08/2014] [Accepted: 09/11/2014] [Indexed: 12/19/2022]
Abstract
Ceramide synthase 2 (CerS2) null mice cannot synthesize very-long acyl chain (C22-C24) ceramides resulting in significant alterations in the acyl chain composition of sphingolipids. We now demonstrate that hepatic triacylglycerol (TG) levels are reduced in the liver but not in the adipose tissue or skeletal muscle of the CerS2 null mouse, both before and after feeding with a high fat diet (HFD), where no weight gain was observed and large hepatic nodules appeared. Uptake of both BODIPY-palmitate and [VH]-palmitate was also abrogated in the hepa- tocytes and liver. The role of a number of key proteins involved in fatty acid uptake was examined, including FATP5, CD36/FAT, FABPpm and cytoplasmic FABP1. Levels of FATP5 and FABP1 were decreased in the CerS2 null mouse liver, whereas CD36/FAT levels were significantly elevated and CD36/FAT was also mislocalized upon insulin treatment. Moreover, treatment of hepatocytes with C22-C24-ceramides down-regulated CD36/FAT levels. Infection of CerS2 null mice with recombinant adeno-associated virus (rAAV)-CerS2 restored normal TG levels and corrected the mislocalization of CD36/FAT, but had no effect on the intracellular localization or levels of FATP5 or FABP1. Together, these results demonstrate that hepatic fatty acid uptake via CD36/FAT can be regulated by altering the acyl chain composition of sphingolipids.
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Regulation of ceramide channel formation and disassembly: Insights on the initiation of apoptosis. Saudi J Biol Sci 2015; 22:760-72. [PMID: 26587005 PMCID: PMC4625378 DOI: 10.1016/j.sjbs.2015.03.005] [Citation(s) in RCA: 30] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/21/2015] [Revised: 03/12/2015] [Accepted: 03/15/2015] [Indexed: 01/04/2023] Open
Abstract
Sphingolipid research has surged in the past two decades and has produced a wide variety of evidence supporting the role of this class of molecules in mediating cellular growth, differentiation, senescence, and apoptosis. Ceramides are a subgroup of sphingolipids (SLs) that are directly involved in the process of initiation of apoptosis. We, and others, have recently shown that ceramides are capable of the formation of protein-permeable channels in mitochondrial outer membranes under physiological conditions. These pores are indeed good candidates for the pathway of release of pro-apoptotic proteins from the mitochondrial intermembrane space (IMS) into the cytosol to initiate intrinsic apoptosis. Here, we review recent findings on the regulation of ceramide channel formation and disassembly, highlighting possible implications on the initiation of the intrinsic apoptotic pathway.
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Key Words
- Apoptosis
- Assembly and disassembly
- Bcl-2 family proteins
- Bcl-2, B cell CLL/lymphoma-2
- Cer, ceramide
- CerS, ceramide synthase
- Ceramide channels
- Chain length
- DES, dihydroceramide desaturase
- DHCer, dihydroceramide
- ER, endoplasmic reticulum
- IMS, intermembrane space
- KSR, 3-ketosphinganine reductase
- MOMP, mitochondrial outer membrane permeability
- Mitochondria
- SLs, sphingolipids
- SM, sphingomyelin
- SPT, serine palmitoyl transferase
- So, sphingosine
- Sphingolipids
- de novo synthesis
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Rodriguez-Cuenca S, Barbarroja N, Vidal-Puig A. Dihydroceramide desaturase 1, the gatekeeper of ceramide induced lipotoxicity. Biochim Biophys Acta Mol Cell Biol Lipids 2015; 1851:40-50. [DOI: 10.1016/j.bbalip.2014.09.021] [Citation(s) in RCA: 51] [Impact Index Per Article: 5.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/24/2014] [Revised: 09/24/2014] [Accepted: 09/25/2014] [Indexed: 12/25/2022]
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Abbott SK, Li H, Muñoz SS, Knoch B, Batterham M, Murphy KE, Halliday GM, Garner B. Altered ceramide acyl chain length and ceramide synthase gene expression in Parkinson’s disease. Mov Disord 2014; 29:518-26. [PMID: 24822250 DOI: 10.1002/mds.25729] [Citation(s) in RCA: 99] [Impact Index Per Article: 9.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/04/2023] Open
Abstract
Genetic studies have provided increasing evidence that ceramide homeostasis plays a role in neurodegenerative diseases including Parkinson’s disease (PD). It is known that the relative amounts of different ceramide molecular species, as defined by their fatty acyl chain length, regulate ceramide function in lipid membranes and in signaling pathways. In the present study we used a comprehensive sphingolipidomic case-control approach to determine the effects of PD on ceramide composition in postmortem brain tissue from the anterior cingulate cortex (a region with significant PD pathology) and the occipital cortex (spared in PD), also assessing mRNA expression of the major ceramide synthase genes that regulate ceramide acyl chain composition in the same tissue using quantitative PCR. In PD anterior cingulate cortex but not occipital cortex, total ceramide and sphingomyelin levels were reduced from control levels by 53% (P < 0.001) and 42% (P < 0.001), respectively. Of the 13 ceramide and 15 sphingomyelin molecular lipid species identified and quantified, there was a significant shift in the ceramide acyl chain composition toward shorter acyl chain length in the PD anterior cingulate cortex. This PD-associated change in ceramide acyl chain composition was accompanied by an upregulation of ceramide synthase-1 gene expression, which we consider may represent a response to reduced ceramide levels. These data suggest a significant shift in ceramide function in lipid membranes and signaling pathways occurs in regions with PD pathology. Identifying the regulatory mechanisms precipitating this change may provide novel targets for future therapeutics.
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Stiban J, Perera M. Very long chain ceramides interfere with C16-ceramide-induced channel formation: A plausible mechanism for regulating the initiation of intrinsic apoptosis. BIOCHIMICA ET BIOPHYSICA ACTA-BIOMEMBRANES 2014; 1848:561-7. [PMID: 25462172 DOI: 10.1016/j.bbamem.2014.11.018] [Citation(s) in RCA: 83] [Impact Index Per Article: 8.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/12/2014] [Revised: 11/13/2014] [Accepted: 11/17/2014] [Indexed: 12/29/2022]
Abstract
Mitochondria mediate both cell survival and death. The intrinsic apoptotic pathway is initiated by the permeabilization of the mitochondrial outer membrane to pro-apoptotic inter-membrane space (IMS) proteins. Many pathways cause the egress of IMS proteins. Of particular interest is the ability of ceramide to self-assemble into dynamic water-filled channels. The formation of ceramide channels is regulated extensively by Bcl-2 family proteins and dihydroceramide. Here, we show that the chain length of biologically active ceramides serves as an important regulatory factor. Ceramides are synthesized by a family of six mammalian ceramide synthases (CerS) each of which produces a subset of ceramides that differ in their fatty acyl chain length. Various ceramides permeabilize mitochondria differentially. Interestingly, the presence of very long chain ceramides reduces the potency of C16-mediated mitochondrial permeabilization indicating that the intercalation of the lipids in the dynamic channel has a destabilizing effect, reminiscent of dihydroceramide inhibition of ceramide channel formation (Stiban et al., 2006). Moreover, mitochondria isolated from cells overexpressing the ceramide synthase responsible for the production of C16-ceramide (CerS5) are permeabilized faster upon the exogenous addition of C16-ceramide whereas they are resistant to permeabilization with added C24-ceramide. On the other hand mitochondria isolated from CerS2-overexpressing cells show the opposite pattern, indicating that the product of CerS2 inhibits C16-channel formation ex vivo and vice versa. This interplay between different ceramide metabolic enzymes and their products adds a new dimension to the complexity of mitochondrial-mediated apoptosis, and emphasizes its role as a key regulatory step that commits cells to life or death.
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Affiliation(s)
- Johnny Stiban
- Department of Biology and Biochemistry, Birzeit University, P.O. Box 14, West Bank 627, Palestine.
| | - Meenu Perera
- Department of Biology, University of Maryland, College Park, MD 20742, USA.
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Alexaki A, Gupta SD, Majumder S, Kono M, Tuymetova G, Harmon JM, Dunn TM, Proia RL. Autophagy regulates sphingolipid levels in the liver. J Lipid Res 2014; 55:2521-31. [PMID: 25332431 DOI: 10.1194/jlr.m051862] [Citation(s) in RCA: 37] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/21/2022] Open
Abstract
Sphingolipid levels are tightly regulated to maintain cellular homeostasis. During pathologic conditions such as in aging, inflammation, and metabolic and neurodegenerative diseases, levels of some sphingolipids, including the bioactive metabolite ceramide, are elevated. Sphingolipid metabolism has been linked to autophagy, a critical catabolic process in both normal cell function and disease; however, the in vivo relevance of the interaction is not well-understood. Here, we show that blocking autophagy in the liver by deletion of the Atg7 gene, which is essential for autophagosome formation, causes an increase in sphingolipid metabolites including ceramide. We also show that overexpression of serine palmitoyltransferase to elevate de novo sphingolipid biosynthesis induces autophagy in the liver. The results reveal autophagy as a process that limits excessive ceramide levels and that is induced by excessive elevation of de novo sphingolipid synthesis in the liver. Dysfunctional autophagy may be an underlying mechanism causing elevations in ceramide that may contribute to pathogenesis in diseases.
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Affiliation(s)
- Aikaterini Alexaki
- Genetics of Development and Disease Branch, National Institute of Diabetes and Digestive and Kidney Diseases, National Institutes of Health, Bethesda, MD 20892
| | - Sita D Gupta
- Departments of Biochemistry Uniformed Services University of the Health Sciences, Bethesda, MD 20184
| | - Saurav Majumder
- Genetics of Development and Disease Branch, National Institute of Diabetes and Digestive and Kidney Diseases, National Institutes of Health, Bethesda, MD 20892
| | - Mari Kono
- Genetics of Development and Disease Branch, National Institute of Diabetes and Digestive and Kidney Diseases, National Institutes of Health, Bethesda, MD 20892
| | - Galina Tuymetova
- Genetics of Development and Disease Branch, National Institute of Diabetes and Digestive and Kidney Diseases, National Institutes of Health, Bethesda, MD 20892
| | - Jeffrey M Harmon
- Molecular Biology and Pharmacology, Uniformed Services University of the Health Sciences, Bethesda, MD 20184
| | - Teresa M Dunn
- Departments of Biochemistry Uniformed Services University of the Health Sciences, Bethesda, MD 20184
| | - Richard L Proia
- Genetics of Development and Disease Branch, National Institute of Diabetes and Digestive and Kidney Diseases, National Institutes of Health, Bethesda, MD 20892
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LU XIAODONG, CHEN YUANYUAN, ZENG TIANTIAN, CHEN LUFANG, SHAO QIXIANG, QIN WENXIN. Knockout of the HCC suppressor gene Lass2 downregulates the expression level of miR-694. Oncol Rep 2014; 32:2696-702. [DOI: 10.3892/or.2014.3527] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/14/2014] [Accepted: 09/02/2014] [Indexed: 11/06/2022] Open
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Klein RL, Hammad SM, Baker NL, Hunt KJ, Al Gadban MM, Cleary PA, Virella G, Lopes-Virella MF. Decreased plasma levels of select very long chain ceramide species are associated with the development of nephropathy in type 1 diabetes. Metabolism 2014; 63:1287-95. [PMID: 25088746 PMCID: PMC5894336 DOI: 10.1016/j.metabol.2014.07.001] [Citation(s) in RCA: 56] [Impact Index Per Article: 5.6] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 03/28/2014] [Revised: 06/25/2014] [Accepted: 07/01/2014] [Indexed: 11/20/2022]
Abstract
OBJECTIVE Sphingolipid metabolism is altered in diabetes and we analyzed the plasma concentrations of sphingolipid species to investigate their association with the development of albuminuria in type 1 patients with diabetes. MATERIALS AND METHODS Samples were collected from 497 type 1 diabetic patients during their enrollment into the Diabetes Control and Complications Trial (DCCT). We determined plasma concentrations of multiple ceramide species and individual sphingoid bases and their phosphates using high performance liquid chromatography-tandem mass spectrometry and investigated their association with the development of albuminuria during 14-20 years of follow-up. RESULTS Patients exhibited normal albumin excretion rates (AER <40 mg/24h) at the time of plasma sampling. Although the majority of patients (N = 291; 59%) exhibited normal levels of albuminuria throughout follow-up, 141 patients (28%) progressed to microalbuminuria (40 mg/24h ≤ AER<300 mg/24h), while 65 (13%) progressed to macroalbuminuria (AER ≥ 300 mg/24h). To test the association of log transformed plasma sphingolipid level with the development of albuminuria, generalized logistic regression models were used where normal, micro- and macroalbuminuria were the outcomes of interest. Models were adjusted for DCCT treatment group, baseline retinopathy, gender, baseline HbA1c %, age, AER, lipid levels, diabetes duration, and the use of ACE/ARB drugs. Increased plasma levels of very long, but not long chain ceramide species measured at DCCT baseline were associated with decreased odds to develop macroalbuminuria during the subsequent nineteen years (DCCT Baseline to EDIC year 8). CONCLUSION These studies demonstrate, prospectively, that decreased plasma levels of select ceramide species are associated with the development of macroalbuminuria in type 1 diabetes.
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Affiliation(s)
- Richard L Klein
- Division of Endocrinology, Metabolism, and Medical Genetics, Department of Medicine, Medical University of South Carolina, Charleston, SC, USA; Research Service, Ralph H. Johnson Department of Veterans Affairs Medical Center, Charleston, SC, USA.
| | - Samar M Hammad
- Department of Regenerative Medicine and Cell Biology, Medical University of South Carolina, Charleston, SC, USA.
| | - Nathaniel L Baker
- Department of Public Health Sciences, Medical University of South Carolina, Charleston, SC, USA
| | - Kelly J Hunt
- Research Service, Ralph H. Johnson Department of Veterans Affairs Medical Center, Charleston, SC, USA; Department of Public Health Sciences, Medical University of South Carolina, Charleston, SC, USA
| | - Mohammed M Al Gadban
- Department of Regenerative Medicine and Cell Biology, Medical University of South Carolina, Charleston, SC, USA
| | - Patricia A Cleary
- The Biostatistics Center, George Washington University, Washington, DC, USA
| | - Gabriel Virella
- Department of Microbiology and Immunology, Medical University of South Carolina, Charleston, SC, USA
| | - Maria F Lopes-Virella
- Division of Endocrinology, Metabolism, and Medical Genetics, Department of Medicine, Medical University of South Carolina, Charleston, SC, USA; Research Service, Ralph H. Johnson Department of Veterans Affairs Medical Center, Charleston, SC, USA
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Sassa T, Kihara A. Metabolism of very long-chain Fatty acids: genes and pathophysiology. Biomol Ther (Seoul) 2014; 22:83-92. [PMID: 24753812 PMCID: PMC3975470 DOI: 10.4062/biomolther.2014.017] [Citation(s) in RCA: 179] [Impact Index Per Article: 17.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/10/2014] [Accepted: 03/03/2014] [Indexed: 01/19/2023] Open
Abstract
Fatty acids (FAs) are highly diverse in terms of carbon (C) chain-length and number of double bonds. FAs with C>20 are called very long-chain fatty acids (VLCFAs). VLCFAs are found not only as constituents of cellular lipids such as sphingolipids and glycerophospholipids but also as precursors of lipid mediators. Our understanding on the function of VLCFAs is growing in parallel with the identification of enzymes involved in VLCFA synthesis or degradation. A variety of inherited diseases, such as ichthyosis, macular degeneration, myopathy, mental retardation, and demyelination, are caused by mutations in the genes encoding VLCFA metabolizing enzymes. In this review, we describe mammalian VLCFAs by highlighting their tissue distribution and metabolic pathways, and we discuss responsible genes and enzymes with reference to their roles in pathophysiology.
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Affiliation(s)
- Takayuki Sassa
- Laboratory of Biochemistry, Faculty of Pharmaceutical Sciences, Hokkaido University, Kita-ku, Sapporo 060-0812, Japan
| | - Akio Kihara
- Laboratory of Biochemistry, Faculty of Pharmaceutical Sciences, Hokkaido University, Kita-ku, Sapporo 060-0812, Japan
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Downregulation of ceramide synthase-6 during epithelial-to-mesenchymal transition reduces plasma membrane fluidity and cancer cell motility. Oncogene 2014; 34:996-1005. [PMID: 24632610 DOI: 10.1038/onc.2014.55] [Citation(s) in RCA: 63] [Impact Index Per Article: 6.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/19/2013] [Revised: 01/13/2014] [Accepted: 01/20/2014] [Indexed: 01/28/2023]
Abstract
Epithelial-to-mesenchymal transition (EMT) promotes cell motility, which is important for the metastasis of malignant cells, and blocks CD95-mediated apoptotic signaling triggered by immune cells and chemotherapeutic regimens. CD95L, the cognate ligand of CD95, can be cleaved by metalloproteases and released as a soluble molecule (cl-CD95L). Unlike transmembrane CD95L, cl-CD95L does not induce apoptosis but triggers cell motility. Electron paramagnetic resonance was used to show that EMT and cl-CD95L treatment both led to augmentation of plasma membrane fluidity that was instrumental in inducing cell migration. Compaction of the plasma membrane is modulated, among other factors, by the ratio of certain lipids such as sphingolipids in the membrane. An integrative analysis of gene expression in NCI tumor cell lines revealed that expression of ceramide synthase-6 (CerS6) decreased during EMT. Furthermore, pharmacological and genetic approaches established that modulation of CerS6 expression/activity in cancer cells altered the level of C16-ceramide, which in turn influenced plasma membrane fluidity and cell motility. Therefore, this study identifies CerS6 as a novel EMT-regulated gene that has a pivotal role in the regulation of cell migration.
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Mosbech MB, Olsen ASB, Neess D, Ben-David O, Klitten LL, Larsen J, Sabers A, Vissing J, Nielsen JE, Hasholt L, Klein AD, Tsoory MM, Hjalgrim H, Tommerup N, Futerman AH, Møller RS, Færgeman NJ. Reduced ceramide synthase 2 activity causes progressive myoclonic epilepsy. Ann Clin Transl Neurol 2014; 1:88-98. [PMID: 25356388 PMCID: PMC4212479 DOI: 10.1002/acn3.28] [Citation(s) in RCA: 44] [Impact Index Per Article: 4.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/04/2013] [Accepted: 12/04/2013] [Indexed: 12/19/2022] Open
Abstract
Objective Ceramides are precursors of complex sphingolipids (SLs), which are important for normal functioning of both the developing and mature brain. Altered SL levels have been associated with many neurodegenerative disorders, including epilepsy, although few direct links have been identified between genes involved in SL metabolism and epilepsy. Methods We used quantitative real-time PCR, Western blotting, and enzymatic assays to determine the mRNA, protein, and activity levels of ceramide synthase 2 (CERS2) in fiibroblasts isolated from parental control subjects and from a patient diagnosed with progressive myoclonic epilepsy (PME). Mass spectrometry and fluorescence microscopy were used to examine the effects of reduced CERS2 activity on cellular lipid composition and plasma membrane functions. Results We identify a novel 27 kb heterozygous deletion including the CERS2 gene in a proband diagnosed with PME. Compared to parental controls, levels of CERS2 mRNA, protein, and activity were reduced by ˜50% in fibroblasts isolated from this proband, resulting in significantly reduced levels of ceramides and sphingomyelins containing the very long-chain fatty acids C24:0 and C26:0. The change in SL composition was also reflected in a reduction in cholera toxin B immunofluorescence, indicating that membrane composition and function are altered. Interpretation We propose that reduced levels of CERS2, and consequently diminished levels of ceramides and SLs containing very long-chain fatty acids, lead to development of PME.
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Affiliation(s)
- Mai-Britt Mosbech
- Department of Biochemistry and Molecular Biology, University of Southern Denmark Odense M, DK-5230, Denmark
| | - Anne S B Olsen
- Department of Biochemistry and Molecular Biology, University of Southern Denmark Odense M, DK-5230, Denmark
| | - Ditte Neess
- Department of Biochemistry and Molecular Biology, University of Southern Denmark Odense M, DK-5230, Denmark
| | - Oshrit Ben-David
- Department of Biological Chemistry, Weizmann Institute of Science Rehovot, 76100, Israel
| | - Laura L Klitten
- The Danish Epilepsy Centre, Filadelfia Dianalund, DK-4293, Denmark
| | - Jan Larsen
- The Danish Epilepsy Centre, Filadelfia Dianalund, DK-4293, Denmark ; Department of Cellular and Molecular Medicine, The Panum Institute, University of Copenhagen Copenhagen, DK-2100, Denmark
| | - Anne Sabers
- Department of Neurology, Rigshospitalet, University of Copenhagen Copenhagen, DK-2100, Denmark
| | - John Vissing
- Department of Neurology, Rigshospitalet, University of Copenhagen Copenhagen, DK-2100, Denmark
| | - Jørgen E Nielsen
- Neurogenetics Clinic, Danish Dementia Research Centre, Department of Neurology, Rigshospitalet, Copenhagen University Hospital Copenhagen, DK-2100, Denmark
| | - Lis Hasholt
- Department of Cellular and Molecular Medicine, The Panum Institute, University of Copenhagen Copenhagen, DK-2100, Denmark
| | - Andres D Klein
- Department of Biological Chemistry, Weizmann Institute of Science Rehovot, 76100, Israel
| | - Michael M Tsoory
- Behavioral and Physiological Phenotyping Unit, Department of Veterinary Resources, Weizmann Institute of Science Rehovot, 76100, Israel
| | - Helle Hjalgrim
- The Danish Epilepsy Centre, Filadelfia Dianalund, DK-4293, Denmark ; Institute for Regional Health Services, University of Southern Denmark Odense, Denmark
| | - Niels Tommerup
- Department of Cellular and Molecular Medicine, The Panum Institute, University of Copenhagen Copenhagen, DK-2100, Denmark
| | - Anthony H Futerman
- Department of Biological Chemistry, Weizmann Institute of Science Rehovot, 76100, Israel
| | - Rikke S Møller
- The Danish Epilepsy Centre, Filadelfia Dianalund, DK-4293, Denmark ; Institute for Regional Health Services, University of Southern Denmark Odense, Denmark
| | - Nils J Færgeman
- Department of Biochemistry and Molecular Biology, University of Southern Denmark Odense M, DK-5230, Denmark
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Altering the sphingolipid acyl chain composition prevents LPS/GLN-mediated hepatic failure in mice by disrupting TNFR1 internalization. Cell Death Dis 2013; 4:e929. [PMID: 24263103 PMCID: PMC3847327 DOI: 10.1038/cddis.2013.451] [Citation(s) in RCA: 34] [Impact Index Per Article: 3.1] [Reference Citation Analysis] [Abstract] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/26/2013] [Revised: 10/08/2013] [Accepted: 10/10/2013] [Indexed: 01/20/2023]
Abstract
The involvement of ceramide in death receptor-mediated apoptosis has been widely examined with most studies focusing on the role of ceramide generated from sphingomyelin hydrolysis. We now analyze the effect of the ceramide acyl chain length by studying tumor necrosis factor α receptor-1 (TNFR1)-mediated apoptosis in a ceramide synthase 2 (CerS2) null mouse, which cannot synthesize very-long acyl chain ceramides. CerS2 null mice were resistant to lipopolysaccharide/galactosamine-mediated fulminant hepatic failure even though TNFα secretion from macrophages was unaffected. Cultured hepatocytes were also insensitive to TNFα-mediated apoptosis. In addition, in both liver and in hepatocytes, caspase activities were not elevated, consistent with inhibition of TNFR1 pro-apoptotic signaling. In contrast, Fas receptor activation resulted in the death of CerS2 null mice. Caspase activation was blocked because of the inability of CerS2 null mice to internalize the TNFR1; whereas Fc-TNFα was internalized to a perinuclear region in hepatocytes from wild-type mice, no internalization was detected in CerS2 null mice. Our results indicate that altering the acyl chain composition of sphingolipids inhibits TNFR1 internalization and inhibits selective pro-apoptotic downstream signaling for apoptosis.
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