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Ali O, Szabó A. Fumonisin distorts the cellular membrane lipid profile: A mechanistic insight. Toxicology 2024; 506:153860. [PMID: 38871209 DOI: 10.1016/j.tox.2024.153860] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/18/2024] [Revised: 06/04/2024] [Accepted: 06/06/2024] [Indexed: 06/15/2024]
Abstract
Monitoring modifications in membrane lipids in association with external stimuli/agents, including fumonisins (FUMs), is a widely employed approach to assess cellular metabolic response/status. FUMs are prevalent fusariotoxins worldwide that have diverse structures with varying toxicity across species; nevertheless, they can induce metabolic disturbances and disease, including cancer. The capacity of FUMs to disrupt membrane lipids, demonstrated across numerous species and organs/tissues, is ascribed to a multitude of factors/events, which range from direct to indirect effects. Certain events are well established, whereas the potential consequences of others remain speculative. The most notable effect is their resemblance to sphingoid bases, which impacts the synthesis of ceramides leading to numerous changes in lipids' composition that are not limited to sphingolipids' composition of the membranes. The next plausible scenario involves the induction of oxidative stress, which is considered an indirect/secondary effect of FUMs. Additional modes of action include modifications of enzyme activities and nuclear signals related to lipid metabolism, although these are likely not yet fully comprehended. This review provides in-depth insight into the current state of these events and their potential mechanistic actions in modifying membrane lipids, with a focus on long-chain fatty acids. This paper also presents a detailed description of the reported modifications to membrane lipids by FUMs.
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Affiliation(s)
- Omeralfaroug Ali
- Agribiotechnology and Precision Breeding for Food Security National Laboratory, Institute of Physiology and Animal Nutrition, Department of Animal Physiology and Health, Hungarian University of Agriculture and Life Sciences, Guba Sándor Str. 40, Kaposvár 7400, Hungary.
| | - András Szabó
- Agribiotechnology and Precision Breeding for Food Security National Laboratory, Institute of Physiology and Animal Nutrition, Department of Animal Physiology and Health, Hungarian University of Agriculture and Life Sciences, Guba Sándor Str. 40, Kaposvár 7400, Hungary; HUN-REN-MATE Mycotoxins in the Food Chain Research Group, Hungarian University of Agriculture and Life Sciences, Guba Sándor Str. 40, Kaposvár 7400, Hungary
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2
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Mu Y, Wang Z, Song L, Ma K, Chen Y, Li P, Yan Z. Modulating lipid bilayer permeability and structure: Impact of hydrophobic chain length, C-3 hydroxyl group, and double bond in sphingosine. J Colloid Interface Sci 2024; 674:513-526. [PMID: 38943912 DOI: 10.1016/j.jcis.2024.06.171] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/19/2024] [Revised: 06/14/2024] [Accepted: 06/23/2024] [Indexed: 07/01/2024]
Abstract
Sphingosine, an amphiphilic molecule, plays a pivotal role as the core structure of sphingolipids, essential constituents of cell membranes. Its unique capability to enhance the permeability of lipid membranes profoundly influences crucial life processes. The molecular structure of sphingosine dictates its mode of entry into lipid bilayers and governs its interactions with lipids, thereby determining membrane permeability. However, the incomplete elucidation of the relationship between the molecular structure of sphingosine and the permeability of lipid membranes persists due to challenges associated with synthesizing sphingosine molecules. A series of sphingosine-derived molecules, featuring diverse hydrophobic chain lengths and distinct headgroup structure, were meticulously designed and successfully synthesized. These molecules were employed to investigate the permeability of large unilamellar vesicles, functioning as model lipid bilayers. With a decrease in the hydrophobic chain length of sphingosine from C15 to C11, the transient leakage ratio of vesicle contents escalated from ∼ 13 % to ∼ 28 %. Although the presence of double bond did not exert a pronounced influence on transient leakage, it significantly affected the continuous leakage ratio. Conversely, modifying the chirality of the C-3 hydroxyl group gives the opposite result. Notably, methylation at the C-3 hydroxyl significantly elevates transient leakage while suppressing the continuous leakage ratio. Additionally, sphingosines that significantly affect vesicle permeability tend to have a more pronounced impact on cell viability. Throughout this leakage process, the charge state of sphingosine-derived molecule aggregates in the solution emerged as a pivotal factor influencing vesicle permeability. Fluorescence lifetime experiments further revealed discernible variations in the effect of sphingosine molecular structure on the mobility of hydrophobic regions within lipid bilayers. These observed distinctions emphasize the impact of molecular structure on intermolecular interactions, extending to the microscopic architecture of membranes, and underscore the significance of subtle alterations in molecular structure and their associated aggregation behaviors in governing membrane permeability.
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Affiliation(s)
- Yonghang Mu
- State Key Laboratory of Heavy Oil Processing, College of Chemistry and Chemical Engineering, China University of Petroleum, Qingdao 266580, China
| | - Zi Wang
- State Key Laboratory of Heavy Oil Processing, College of Chemistry and Chemical Engineering, China University of Petroleum, Qingdao 266580, China.
| | - Linhua Song
- State Key Laboratory of Heavy Oil Processing, College of Chemistry and Chemical Engineering, China University of Petroleum, Qingdao 266580, China
| | - Kun Ma
- ISIS Facility, Rutherford Appleton Laboratory, STFC, Chilton, Didcot, Oxon OX11 0QX, UK
| | - Yao Chen
- ISIS Facility, Rutherford Appleton Laboratory, STFC, Chilton, Didcot, Oxon OX11 0QX, UK
| | - Peixun Li
- ISIS Facility, Rutherford Appleton Laboratory, STFC, Chilton, Didcot, Oxon OX11 0QX, UK
| | - Zifeng Yan
- State Key Laboratory of Heavy Oil Processing, College of Chemistry and Chemical Engineering, China University of Petroleum, Qingdao 266580, China.
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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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4
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Means RE, Katz SG. Balancing life and death: BCL-2 family members at diverse ER-mitochondrial contact sites. FEBS J 2022; 289:7075-7112. [PMID: 34668625 DOI: 10.1111/febs.16241] [Citation(s) in RCA: 18] [Impact Index Per Article: 9.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/23/2021] [Revised: 10/11/2021] [Accepted: 10/19/2021] [Indexed: 01/13/2023]
Abstract
The outer mitochondrial membrane is a busy place. One essential activity for cellular survival is the regulation of membrane integrity by the BCL-2 family of proteins. Another critical facet of the outer mitochondrial membrane is its close approximation with the endoplasmic reticulum. These mitochondrial-associated membranes (MAMs) occupy a significant fraction of the mitochondrial surface and serve as key signaling hubs for multiple cellular processes. Each of these pathways may be considered as forming their own specialized MAM subtype. Interestingly, like membrane permeabilization, most of these pathways play critical roles in regulating cellular survival and death. Recently, the pro-apoptotic BCL-2 family member BOK has been found within MAMs where it plays important roles in their structure and function. This has led to a greater appreciation that multiple BCL-2 family proteins, which are known to participate in numerous functions throughout the cell, also have roles within MAMs. In this review, we evaluate several MAM subsets, their role in cellular homeostasis, and the contribution of BCL-2 family members to their functions.
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Affiliation(s)
- Robert E Means
- Department of Pathology, Yale University School of Medicine, New Haven, CT, USA
| | - Samuel G Katz
- Department of Pathology, Yale University School of Medicine, New Haven, CT, USA
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McGurk KA, Keavney BD, Nicolaou A. Circulating ceramides as biomarkers of cardiovascular disease: Evidence from phenotypic and genomic studies. Atherosclerosis 2021; 327:18-30. [PMID: 34004484 DOI: 10.1016/j.atherosclerosis.2021.04.021] [Citation(s) in RCA: 31] [Impact Index Per Article: 10.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 02/28/2021] [Revised: 04/25/2021] [Accepted: 04/30/2021] [Indexed: 12/20/2022]
Abstract
There is a need for new biomarkers of atherosclerotic cardiovascular disease (ACVD), the main cause of death globally. Ceramides, a class of potent bioactive lipid mediators, have signalling roles in apoptosis, cellular stress and inflammation. Recent studies have highlighted circulating ceramides as novel biomarkers of coronary artery disease, type-2 diabetes and insulin resistance. Ceramides are highly regulated by enzymatic reactions throughout the body in terms of their activity and metabolism, including production, degradation and transport. The genetic studies that have been completed to date on the main ceramide species found in circulation are described, highlighting the importance of DNA variants in genes involved in ceramide biosynthesis as key influencers of heritable, circulating ceramide levels. We also review studies of disease associations with ceramides and discuss mechanistic insights deriving from recent genomic studies. The signalling activities of ceramides in vascular inflammation and apoptosis, associations between circulating ceramides and coronary artery disease risk, type-2 diabetes and insulin resistance, and the potential importance of ceramides with regard to ACVD risk factors, such as blood pressure, lipoproteins and lifestyle factors, are also discussed.
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Affiliation(s)
- Kathryn A McGurk
- Division of Cardiovascular Sciences, Faculty of Biology, Medicine and Health, Manchester Academic Health Science Centre, University of Manchester, UK; Laboratory for Lipidomics and Lipid Research, Division of Pharmacy and Optometry, Faculty of Biology, Medicine and Health, Manchester Academic Health Science Centre, University of Manchester, UK
| | - Bernard D Keavney
- Division of Cardiovascular Sciences, Faculty of Biology, Medicine and Health, Manchester Academic Health Science Centre, University of Manchester, UK; Manchester Heart Centre, Manchester University NHS Foundation Trust, UK
| | - Anna Nicolaou
- Laboratory for Lipidomics and Lipid Research, Division of Pharmacy and Optometry, Faculty of Biology, Medicine and Health, Manchester Academic Health Science Centre, University of Manchester, UK; Lydia Becker Institute of Immunology and Inflammation, Faculty of Biology, Medicine and Health, The University of Manchester, Manchester Academic Health Science Centre, Manchester, UK.
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6
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Giamogante F, Poggio E, Barazzuol L, Covallero A, Calì T. Apoptotic signals at the endoplasmic reticulum-mitochondria interface. ADVANCES IN PROTEIN CHEMISTRY AND STRUCTURAL BIOLOGY 2021; 126:307-343. [PMID: 34090618 DOI: 10.1016/bs.apcsb.2021.02.007] [Citation(s) in RCA: 16] [Impact Index Per Article: 5.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/12/2022]
Abstract
The maintenance of cellular homeostasis involves the participation of multiple organelles, such as the endoplasmic reticulum (ER) and mitochondria. Specifically, ER plays a key role in calcium (Ca2+) storage, lipid synthesis, protein folding, and assembly, while mitochondria are the "energy factories" and provide energy to drive intracellular processes. Hence, alteration in ER or mitochondrial homeostasis has detrimental effects on cell survival, being linked to the triggering of apoptosis, a programmed form of cell death. Besides, ER stress conditions affect mitochondria functionality and vice-versa, as ER and mitochondria communicate via mitochondria-associated ER membranes (MAMs) to carry out a number of fundamental cellular functions. It is not surprising, thus, that also MAMs perturbations are involved in the regulation of apoptosis. This chapter intends to accurately discuss the involvement of MAMs in apoptosis, highlighting their crucial role in controlling this delicate cellular process.
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Affiliation(s)
- Flavia Giamogante
- Department of Biomedical Sciences, University of Padova, Padova, Italy
| | - Elena Poggio
- Department of Biomedical Sciences, University of Padova, Padova, Italy
| | - Lucia Barazzuol
- Department of Biomedical Sciences, University of Padova, Padova, Italy
| | - Alberto Covallero
- Department of Biomedical Sciences, University of Padova, Padova, Italy
| | - Tito Calì
- Department of Biomedical Sciences, University of Padova, Padova, Italy.
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Hadas Y, Vincek AS, Youssef E, Żak MM, Chepurko E, Sultana N, Sharkar MTK, Guo N, Komargodski R, Kurian AA, Kaur K, Magadum A, Fargnoli A, Katz MG, Hossain N, Kenigsberg E, Dubois NC, Schadt E, Hajjar R, Eliyahu E, Zangi L. Altering Sphingolipid Metabolism Attenuates Cell Death and Inflammatory Response After Myocardial Infarction. Circulation 2020; 141:916-930. [PMID: 31992066 PMCID: PMC7135928 DOI: 10.1161/circulationaha.119.041882] [Citation(s) in RCA: 89] [Impact Index Per Article: 22.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 05/21/2019] [Accepted: 02/06/2020] [Indexed: 12/28/2022]
Abstract
BACKGROUND Sphingolipids have recently emerged as a biomarker of recurrence and mortality after myocardial infarction (MI). The increased ceramide levels in mammalian heart tissues during acute MI, as demonstrated by several groups, is associated with higher cell death rates in the left ventricle and deteriorated cardiac function. Ceramidase, the only enzyme known to hydrolyze proapoptotic ceramide, generates sphingosine, which is then phosphorylated by sphingosine kinase to produce the prosurvival molecule sphingosine-1-phosphate. We hypothesized that Acid Ceramidase (AC) overexpression would counteract the negative effects of elevated ceramide and promote cell survival, thereby providing cardioprotection after MI. METHODS We performed transcriptomic, sphingolipid, and protein analyses to evaluate sphingolipid metabolism and signaling post-MI. We investigated the effect of altering ceramide metabolism through a loss (chemical inhibitors) or gain (modified mRNA [modRNA]) of AC function post hypoxia or MI. RESULTS We found that several genes involved in de novo ceramide synthesis were upregulated and that ceramide (C16, C20, C20:1, and C24) levels had significantly increased 24 hours after MI. AC inhibition after hypoxia or MI resulted in reduced AC activity and increased cell death. By contrast, enhancing AC activity via AC modRNA treatment increased cell survival after hypoxia or MI. AC modRNA-treated mice had significantly better heart function, longer survival, and smaller scar size than control mice 28 days post-MI. We attributed the improvement in heart function post-MI after AC modRNA delivery to decreased ceramide levels, lower cell death rates, and changes in the composition of the immune cell population in the left ventricle manifested by lowered abundance of proinflammatory detrimental neutrophils. CONCLUSIONS Our findings suggest that transiently altering sphingolipid metabolism through AC overexpression is sufficient and necessary to induce cardioprotection post-MI, thereby highlighting the therapeutic potential of AC modRNA in ischemic heart disease.
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Affiliation(s)
- Yoav Hadas
- Cardiovascular Research Center, Icahn School of Medicine at Mount Sinai, New York, NY, USA
- Department of Genetics and Genomic Sciences, Icahn School of Medicine at Mount Sinai, New York, NY, USA
- Black Family Stem Cell Institute, Icahn School of Medicine at Mount Sinai, New York, NY, USA
| | - Adam S. Vincek
- Department of Genetics and Genomic Sciences, Icahn School of Medicine at Mount Sinai, New York, NY, USA
| | - Elias Youssef
- Cardiovascular Research Center, Icahn School of Medicine at Mount Sinai, New York, NY, USA
- Department of Genetics and Genomic Sciences, Icahn School of Medicine at Mount Sinai, New York, NY, USA
- Black Family Stem Cell Institute, Icahn School of Medicine at Mount Sinai, New York, NY, USA
| | - Magdalena M. Żak
- Cardiovascular Research Center, Icahn School of Medicine at Mount Sinai, New York, NY, USA
- Department of Genetics and Genomic Sciences, Icahn School of Medicine at Mount Sinai, New York, NY, USA
- Black Family Stem Cell Institute, Icahn School of Medicine at Mount Sinai, New York, NY, USA
| | - Elena Chepurko
- Cardiovascular Research Center, Icahn School of Medicine at Mount Sinai, New York, NY, USA
- Department of Genetics and Genomic Sciences, Icahn School of Medicine at Mount Sinai, New York, NY, USA
- Black Family Stem Cell Institute, Icahn School of Medicine at Mount Sinai, New York, NY, USA
| | - Nishat Sultana
- Cardiovascular Research Center, Icahn School of Medicine at Mount Sinai, New York, NY, USA
- Department of Genetics and Genomic Sciences, Icahn School of Medicine at Mount Sinai, New York, NY, USA
- Black Family Stem Cell Institute, Icahn School of Medicine at Mount Sinai, New York, NY, USA
| | - Mohammad Tofael Kabir Sharkar
- Cardiovascular Research Center, Icahn School of Medicine at Mount Sinai, New York, NY, USA
- Department of Genetics and Genomic Sciences, Icahn School of Medicine at Mount Sinai, New York, NY, USA
- Black Family Stem Cell Institute, Icahn School of Medicine at Mount Sinai, New York, NY, USA
| | - Ningning Guo
- Department of Genetics and Genomic Sciences, Icahn School of Medicine at Mount Sinai, New York, NY, USA
| | - Rinat Komargodski
- Cardiovascular Research Center, Icahn School of Medicine at Mount Sinai, New York, NY, USA
- Department of Genetics and Genomic Sciences, Icahn School of Medicine at Mount Sinai, New York, NY, USA
- Black Family Stem Cell Institute, Icahn School of Medicine at Mount Sinai, New York, NY, USA
| | - Ann Anu Kurian
- Cardiovascular Research Center, Icahn School of Medicine at Mount Sinai, New York, NY, USA
- Department of Genetics and Genomic Sciences, Icahn School of Medicine at Mount Sinai, New York, NY, USA
- Black Family Stem Cell Institute, Icahn School of Medicine at Mount Sinai, New York, NY, USA
| | - Keerat Kaur
- Cardiovascular Research Center, Icahn School of Medicine at Mount Sinai, New York, NY, USA
- Department of Genetics and Genomic Sciences, Icahn School of Medicine at Mount Sinai, New York, NY, USA
- Black Family Stem Cell Institute, Icahn School of Medicine at Mount Sinai, New York, NY, USA
| | - Ajit Magadum
- Cardiovascular Research Center, Icahn School of Medicine at Mount Sinai, New York, NY, USA
- Department of Genetics and Genomic Sciences, Icahn School of Medicine at Mount Sinai, New York, NY, USA
- Black Family Stem Cell Institute, Icahn School of Medicine at Mount Sinai, New York, NY, USA
| | - Anthony Fargnoli
- Cardiovascular Research Center, Icahn School of Medicine at Mount Sinai, New York, NY, USA
| | - Michael G. Katz
- Cardiovascular Research Center, Icahn School of Medicine at Mount Sinai, New York, NY, USA
| | - Nadia Hossain
- Cardiovascular Research Center, Icahn School of Medicine at Mount Sinai, New York, NY, USA
- Department of Genetics and Genomic Sciences, Icahn School of Medicine at Mount Sinai, New York, NY, USA
- Black Family Stem Cell Institute, Icahn School of Medicine at Mount Sinai, New York, NY, USA
| | - Ephraim Kenigsberg
- Department of Genetics and Genomic Sciences, Icahn School of Medicine at Mount Sinai, New York, NY, USA
| | - Nicole C. Dubois
- Department of Developmental and Regenerative Biology and The Mindich Child Health and Development Institute, Icahn School of Medicine at Mount Sinai, New York, NY, USA
- Black Family Stem Cell Institute, Icahn School of Medicine at Mount Sinai, New York, NY, USA
| | - Eric Schadt
- Department of Genetics and Genomic Sciences, Icahn School of Medicine at Mount Sinai, New York, NY, USA
- Multiscale Biology Institute, Icahn School of Medicine at Mount Sinai, New York, NY, USA
| | - Roger Hajjar
- Phospholamban Foundation, Amsterdam, Netherlands
| | - Efrat Eliyahu
- Department of Genetics and Genomic Sciences, Icahn School of Medicine at Mount Sinai, New York, NY, USA
- Multiscale Biology Institute, Icahn School of Medicine at Mount Sinai, New York, NY, USA
| | - Lior Zangi
- Cardiovascular Research Center, Icahn School of Medicine at Mount Sinai, New York, NY, USA
- Department of Genetics and Genomic Sciences, Icahn School of Medicine at Mount Sinai, New York, NY, USA
- Black Family Stem Cell Institute, Icahn School of Medicine at Mount Sinai, New York, NY, USA
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Gutiérrez-Nájera NA, Saucedo-García M, Noyola-Martínez L, Vázquez-Vázquez C, Palacios-Bahena S, Carmona-Salazar L, Plasencia J, El-Hafidi M, Gavilanes-Ruiz M. Sphingolipid Effects on the Plasma Membrane Produced by Addition of Fumonisin B1 to Maize Embryos. PLANTS (BASEL, SWITZERLAND) 2020; 9:E150. [PMID: 31979343 PMCID: PMC7076497 DOI: 10.3390/plants9020150] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 12/31/2019] [Revised: 01/13/2020] [Accepted: 01/15/2020] [Indexed: 12/15/2022]
Abstract
Fumonisin B1 is a mycotoxin produced by Fusarium verticillioides that modifies the membrane properties from animal cells and inhibits complex sphingolipids synthesis through the inhibition of ceramide synthase. The aim of this work was to determine the effect of Fumonisin B1 on the plant plasma membrane when the mycotoxin was added to germinating maize embryos. Fumonisin B1 addition to the embryos diminished plasma membrane fluidity, increased electrolyte leakage, caused a 7-fold increase of sphinganine and a small decrease in glucosylceramide in the plasma membrane, without affecting phytosphingosine levels or fatty acid composition. A 20%-30% inhibition of the plasma membrane H+-ATPase activity was observed when embryos were germinated in the presence of the mycotoxin. Such inhibition was only associated to the decrease in glucosylceramide and the addition of exogenous ceramide to the embryos relieved the inhibition of Fumonisin B1. These results indicate that exposure of the maize embryos for 24 h to Fumonisin B1 allowed the mycotoxin to target ceramide synthase at the endoplasmic reticulum, eliciting an imbalance of endogenous sphingolipids. The latter disrupted membrane properties and inhibited the plasma membrane H+-ATPase activity. Altogether, these results illustrate the mode of action of the pathogen and a plant defense strategy.
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Affiliation(s)
- Nora A. Gutiérrez-Nájera
- Instituto Nacional de Medicina Genómica. Periférico Sur 4124, Torre 2, 5° piso. Álvaro Obregón 01900, Cd. de México, Mexico;
| | - Mariana Saucedo-García
- Instituto de Ciencias Agropecuarias, Universidad Autónoma del Estado de Hidalgo, Avenida Universidad Km. 1, Rancho Universitario, Tulancingo-Santiago, Tulantepec, Tulancingo 43600, Hidalgo, Mexico;
| | - Liliana Noyola-Martínez
- Departamento de Bioquímica, Facultad de Química, UNAM. Cd. Universitaria. Coyoacán 04510, Cd. de México, Mexico; (L.N.-M.); (C.V.-V.); (S.P.-B.); (L.C.-S.); (J.P.)
| | - Christian Vázquez-Vázquez
- Departamento de Bioquímica, Facultad de Química, UNAM. Cd. Universitaria. Coyoacán 04510, Cd. de México, Mexico; (L.N.-M.); (C.V.-V.); (S.P.-B.); (L.C.-S.); (J.P.)
| | - Silvia Palacios-Bahena
- Departamento de Bioquímica, Facultad de Química, UNAM. Cd. Universitaria. Coyoacán 04510, Cd. de México, Mexico; (L.N.-M.); (C.V.-V.); (S.P.-B.); (L.C.-S.); (J.P.)
| | - Laura Carmona-Salazar
- Departamento de Bioquímica, Facultad de Química, UNAM. Cd. Universitaria. Coyoacán 04510, Cd. de México, Mexico; (L.N.-M.); (C.V.-V.); (S.P.-B.); (L.C.-S.); (J.P.)
| | - Javier Plasencia
- Departamento de Bioquímica, Facultad de Química, UNAM. Cd. Universitaria. Coyoacán 04510, Cd. de México, Mexico; (L.N.-M.); (C.V.-V.); (S.P.-B.); (L.C.-S.); (J.P.)
| | - Mohammed El-Hafidi
- Departamento de Bioquímica. Instituto Nacional de Cardiología “Ignacio Chávez”. Juan Badiano 1. Tlalpan 14080, Cd. de México, Mexico;
| | - Marina Gavilanes-Ruiz
- Departamento de Bioquímica, Facultad de Química, UNAM. Cd. Universitaria. Coyoacán 04510, Cd. de México, Mexico; (L.N.-M.); (C.V.-V.); (S.P.-B.); (L.C.-S.); (J.P.)
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Prokaryotic and Mitochondrial Lipids: A Survey of Evolutionary Origins. ADVANCES IN EXPERIMENTAL MEDICINE AND BIOLOGY 2019. [PMID: 31502197 DOI: 10.1007/978-3-030-21162-2_2] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 03/28/2024]
Abstract
Mitochondria and bacteria share a myriad of properties since it is believed that the powerhouses of the eukaryotic cell have evolved from a prokaryotic origin. Ribosomal RNA sequences, DNA architecture and metabolism are strikingly similar in these two entities. Proteins and nucleic acids have been a hallmark for comparison between mitochondria and prokaryotes. In this chapter, similarities (and differences) between mitochondrial and prokaryotic membranes are addressed with a focus on structure-function relationship of different lipid classes. In order to be suitable for the theme of the book, a special emphasis is reserved to the effects of bioactive sphingolipids, mainly ceramide, on mitochondrial membranes and their roles in initiating programmed cell death.
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10
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Development of lysosome-mimicking vesicles to study the effect of abnormal accumulation of sphingosine on membrane properties. Sci Rep 2017. [PMID: 28638081 PMCID: PMC5479847 DOI: 10.1038/s41598-017-04125-6] [Citation(s) in RCA: 22] [Impact Index Per Article: 3.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/09/2023] Open
Abstract
Synthetic systems are widely used to unveil the molecular mechanisms of complex cellular events. Artificial membranes are key examples of models employed to address lipid-lipid and lipid-protein interactions. In this work, we developed a new synthetic system that more closely resembles the lysosome – the lysosome-mimicking vesicles (LMVs) – displaying stable acid-to-neutral pH gradient across the membrane. To evaluate the advantages of this synthetic system, we assessed the distinct effects of sphingosine (Sph) accumulation in membrane structure and biophysical properties of standard liposomes (no pH gradient) and in LMVs with lipid composition tuned to mimic physiological- or NPC1-like lysosomes. Ternary 1-palmitoyl-2-oleoyl-sn-glycero-3-phosphocholine (POPC)/Sphingomyelin (SM)/Cholesterol (Chol) mixtures with, respectively, low and high Chol/SM levels were prepared. The effect of Sph on membrane permeability and biophysical properties was evaluated by fluorescence spectroscopy, electrophoretic and dynamic light scattering. The results showed that overall Sph has the ability to cause a shift in vesicle surface charge, increase membrane order and promote a rapid increase in membrane permeability. These effects are enhanced in NPC1- LMVs. The results suggest that lysosomal accumulation of these lipids, as observed under pathological conditions, might significantly affect lysosomal membrane structure and integrity, and therefore contribute to the impairment of cell function.
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11
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Cell membrane modulation as adjuvant in cancer therapy. Cancer Treat Rev 2016; 52:48-57. [PMID: 27889637 DOI: 10.1016/j.ctrv.2016.10.008] [Citation(s) in RCA: 235] [Impact Index Per Article: 29.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/23/2016] [Revised: 10/24/2016] [Accepted: 10/27/2016] [Indexed: 12/25/2022]
Abstract
Cancer is a complex disease involving numerous biological processes, which can exist in parallel, can be complementary, or are engaged when needed and as such can replace each other. This redundancy in possibilities cancer cells have, are fundamental to failure of therapy. However, intrinsic features of tumor cells and tumors as a whole provide also opportunities for therapy. Here we discuss the unique and specific makeup and arrangement of cell membranes of tumor cells and how these may help treatment. Interestingly, knowledge on cell membranes and associated structures is present already for decades, while application of membrane modification and manipulation as part of cancer therapy is lagging. Recent developments of scientific tools concerning lipids and lipid metabolism, opened new and previously unknown aspects of tumor cells and indicate possible differences in lipid composition and membrane function of tumor cells compared to healthy cells. This field, coined Lipidomics, demonstrates the importance of lipid components in cell membrane in several illnesses. Important alterations in cancer, and specially in resistant cancer cells compared to normal cells, opened the door to new therapeutic strategies. Moreover, the ability to modulate membrane components and/or properties has become a reality. Here, developments in cancer-related Lipidomics and strategies to interfere specifically with cancer cell membranes and how these affect cancer treatment are discussed. We hypothesize that combination of lipid or membrane targeted strategies with available care to improve chemotherapy, radiotherapy and immunotherapy will bring the much needed change in treatment in the years to come.
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12
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Colombini M. Ceramide channels and mitochondrial outer membrane permeability. J Bioenerg Biomembr 2016; 49:57-64. [PMID: 26801188 DOI: 10.1007/s10863-016-9646-z] [Citation(s) in RCA: 59] [Impact Index Per Article: 7.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/25/2015] [Accepted: 01/13/2016] [Indexed: 02/07/2023]
Abstract
Among the permeability pathways in the mitochondrial outer membrane (MOM), whose elucidation was pioneered by Kathleen Kinnally, there is one formed by the lipid, ceramide. Electron microscopic visualization shows that ceramide channels are large cylindrical structures of varying pore size, with a most frequent size of 10 nm in diameter, large enough to allow all soluble proteins to translocate between the cytosol and the mitochondrial intermembrane space. Similar results were obtained with electrophysiological measurements. Studies of the dynamics of the channels are consistent with a right cylinder. Ceramide channels form at mole fractions of ceramide that are found in the MOM early in the apoptotic process, before or at the time of protein release from mitochondria. That these channels are good candidates for the protein release pathway is supported by the fact that channel formation is inhibited by anti-apoptotic proteins and favored by Bax. Bcl-xL inhibits ceramide channel formation by binding to the apolar ceramide tails using its hydrophobic grove. Bax interaction with the polar regions of ceramide results in MOM permeabilization through synergy with ceramide. Evidence that ceramide channels actually function to favor apoptosis in vivo is supported by the expression of Bcl-xL containing point mutations in cells induced to undergo apoptosis. The Bcl-xL mutants inhibit differentially Bax and ceramide channels and thus tease apart, to some extent, these two modes of MOM permeabilization. Ceramide channels have the right properties and appropriate regulation to be key players in the induction of apoptosis.
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Affiliation(s)
- Marco Colombini
- Department of Biology, University of Maryland, College Park, MD, 20742, USA.
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13
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Teixeira V, Costa V. Unraveling the role of the Target of Rapamycin signaling in sphingolipid metabolism. Prog Lipid Res 2015; 61:109-33. [PMID: 26703187 DOI: 10.1016/j.plipres.2015.11.001] [Citation(s) in RCA: 31] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/10/2015] [Revised: 11/04/2015] [Accepted: 11/09/2015] [Indexed: 02/06/2023]
Abstract
Sphingolipids are important bioactive molecules that regulate basic aspects of cellular metabolism and physiology, including cell growth, adhesion, migration, senescence, apoptosis, endocytosis, and autophagy in yeast and higher eukaryotes. Since they have the ability to modulate the activation of several proteins and signaling pathways, variations in the relative levels of different sphingolipid species result in important changes in overall cellular functions and fate. Sphingolipid metabolism and their route of synthesis are highly conserved from yeast to mammalian cells. Studies using the budding yeast Saccharomyces cerevisiae have served in many ways to foster our understanding of sphingolipid dynamics and their role in the regulation of cellular processes. In the past decade, studies in S. cerevisiae have unraveled a functional association between the Target of Rapamycin (TOR) pathway and sphingolipids, showing that both TOR Complex 1 (TORC1) and TOR Complex 2 (TORC2) branches control temporal and spatial aspects of sphingolipid metabolism in response to physiological and environmental cues. In this review, we report recent findings in this emerging and exciting link between the TOR pathway and sphingolipids and implications in human health and disease.
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Affiliation(s)
- Vitor Teixeira
- Instituto de Investigação e Inovação em Saúde, Universidade do Porto, Rua Alfredo Allen, 208, 4200-135 Porto, Portugal; IBMC, Instituto de Biologia Molecular e Celular, Porto, Portugal; ICBAS, Instituto de Ciências Biomédicas Abel Salazar, Departamento de Biologia Molecular, Universidade do Porto, Rua de Jorge Viterbo Ferreira, 228, 4050-313 Porto, Portugal
| | - Vítor Costa
- Instituto de Investigação e Inovação em Saúde, Universidade do Porto, Rua Alfredo Allen, 208, 4200-135 Porto, Portugal; IBMC, Instituto de Biologia Molecular e Celular, Porto, Portugal; ICBAS, Instituto de Ciências Biomédicas Abel Salazar, Departamento de Biologia Molecular, Universidade do Porto, Rua de Jorge Viterbo Ferreira, 228, 4050-313 Porto, Portugal.
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14
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Zhou K, Blom T. Trafficking and Functions of Bioactive Sphingolipids: Lessons from Cells and Model Membranes. Lipid Insights 2015; 8:11-20. [PMID: 26715852 PMCID: PMC4685176 DOI: 10.4137/lpi.s31615] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/02/2015] [Revised: 11/08/2015] [Accepted: 11/10/2015] [Indexed: 12/15/2022] Open
Abstract
Ceramide and sphingosine and their phosphorylated counterparts are recognized as "bioactive sphingolipids" and modulate membrane integrity, the activity of enzymes, or act as ligands of G protein-coupled receptors. The subcellular distribution of the bioactive sphingolipids is central to their function as the same lipid can mediate diametrically opposite effects depending on its location. To ensure that these lipids are present in the right amount and in the appropriate organelles, cells employ selective lipid transport and compartmentalize sphingolipid-metabolizing enzymes to characteristic subcellular sites. Our knowledge of key mechanisms involved in sphingolipid signaling and trafficking has increased substantially in the past decades-thanks to advances in biochemical and cell biological methods. In this review, we focus on the bioactive sphingolipids and discuss how the combination of studies in cells and in model membranes have contributed to our understanding of how they behave and function in living organisms.
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Affiliation(s)
- Kecheng Zhou
- Department of Anatomy, Faculty of Medicine, University of Helsinki, Helsinki, Finland
| | - Tomas Blom
- Department of Anatomy, Faculty of Medicine, University of Helsinki, Helsinki, Finland
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15
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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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16
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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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Jiménez-Rojo N, Sot J, Viguera AR, Collado MI, Torrecillas A, Gómez-Fernández JC, Goñi FM, Alonso A. Membrane permeabilization induced by sphingosine: effect of negatively charged lipids. Biophys J 2015; 106:2577-84. [PMID: 24940775 DOI: 10.1016/j.bpj.2014.04.038] [Citation(s) in RCA: 16] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/28/2014] [Revised: 04/14/2014] [Accepted: 04/23/2014] [Indexed: 10/25/2022] Open
Abstract
Sphingosine [(2S, 3R, 4E)-2-amino-4-octadecen-1, 3-diol] is the most common sphingoid long chain base in sphingolipids. It is the precursor of important cell signaling molecules, such as ceramides. In the last decade it has been shown to act itself as a potent metabolic signaling molecule, by activating a number of protein kinases. Moreover, sphingosine has been found to permeabilize phospholipid bilayers, giving rise to vesicle leakage. The present contribution intends to analyze the mechanism by which this bioactive lipid induces vesicle contents release, and the effect of negatively charged bilayers in the release process. Fluorescence lifetime measurements and confocal fluorescence microscopy have been applied to observe the mechanism of sphingosine efflux from large and giant unilamellar vesicles; a graded-release efflux has been detected. Additionally, stopped-flow measurements have shown that the rate of vesicle permeabilization increases with sphingosine concentration. Because at the physiological pH sphingosine has a net positive charge, its interaction with negatively charged phospholipids (e.g., bilayers containing phosphatidic acid together with sphingomyelins, phosphatidylethanolamine, and cholesterol) gives rise to a release of vesicular contents, faster than with electrically neutral bilayers. Furthermore, phosphorous 31-NMR and x-ray data show the capacity of sphingosine to facilitate the formation of nonbilayer (cubic phase) intermediates in negatively charged membranes. The data might explain the pathogenesis of Niemann-Pick type C1 disease.
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Affiliation(s)
- Noemi Jiménez-Rojo
- Unidad de Biofísica (CSIC, UPV/EHU) and Departamento de Bioquímica, Universidad del País Vasco, Bilbao, Spain
| | - Jesús Sot
- Unidad de Biofísica (CSIC, UPV/EHU) and Departamento de Bioquímica, Universidad del País Vasco, Bilbao, Spain
| | - Ana R Viguera
- Unidad de Biofísica (CSIC, UPV/EHU) and Departamento de Bioquímica, Universidad del País Vasco, Bilbao, Spain
| | - M Isabel Collado
- Servicio General de Resonancia Magnética Nuclear, Universidad del País Vasco, Bilbao, Spain
| | - Alejandro Torrecillas
- Sección de Biología Molecular, Servicio de Apoyo a la Investigación, Universidad de Murcia
| | - J C Gómez-Fernández
- Departamento de Bioquímica y Biología Molecular-A, Facultad de Veterinaria, Universidad de Murcia, Regional Campus of International Excellence "Campus Mare Nostrum", Murcia, Spain
| | - Félix M Goñi
- Unidad de Biofísica (CSIC, UPV/EHU) and Departamento de Bioquímica, Universidad del País Vasco, Bilbao, Spain
| | - Alicia Alonso
- Unidad de Biofísica (CSIC, UPV/EHU) and Departamento de Bioquímica, Universidad del País Vasco, Bilbao, Spain.
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18
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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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Short-chain glycoceramides promote intracellular mitoxantrone delivery from novel nanoliposomes into breast cancer cells. Pharm Res 2014; 32:1354-67. [PMID: 25319103 DOI: 10.1007/s11095-014-1539-4] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/24/2014] [Accepted: 09/29/2014] [Indexed: 12/20/2022]
Abstract
PURPOSE To improve therapeutic activity of mitoxantrone (MTO)-based chemotherapy by reducing toxicity through encapsulation in nanoliposomes and enhancing intracellular drug delivery using short-chain sphingolipid (SCS) mediated tumor cell membrane permeabilization. METHODS Standard (MTOL) and nanoliposomes enriched with the SCS, C8-Glucosylceramide or C8-Galactosylceramide (SCS-MTOL) were loaded by a transmembrane ammonium sulphate gradient and characterized by DLS and cryo-TEM. Intracellular MTO delivery was measured by flow cytometry and imaged by fluorescence microscopy. In vitro cytotoxicity was studied in breast carcinoma cell lines. Additionally, live cell confocal microscopy addressed the drug delivery mechanism by following the intracellular fate of the nanoliposomes, the SCS and MTO. Intratumoral MTO localization in relation to CD31-positive tumor vessels and CD11b positive cells was studied in an orthotopic MCF-7 breast cancer xenograft. RESULTS Stable SCS-MTOL were developed increasing MTO delivery and cytotoxicity to tumor cells compared to standard MTOL. This effect was much less pronounced in normal cells. The drug delivery mechanism involved a transfer of SCS to the cell membrane, independently of drug transfer and not involving nanoliposome internalization. MTO was detected intratumorally upon MTOL and SCS-MTOL treatment, but not after free MTO, suggesting an important improvement in tumor drug delivery by nanoliposomal formulation. Nanoliposomal MTO delivery and cellular uptake was heterogeneous throughout the tumor and clearly correlated with CD31-positive tumor vessels. Yet, MTO uptake by CD11b positive cells in tumor stroma was minor. CONCLUSIONS Nanoliposomal encapsulation improves intratumoral MTO delivery over free drug. Liposome bilayer-incorporated SCS preferentially permeabilize tumor cell membranes enhancing intracellular MTO delivery.
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20
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Lysosomotropic agents: impact on lysosomal membrane permeabilization and cell death. Biochem Soc Trans 2014; 42:1460-4. [DOI: 10.1042/bst20140145] [Citation(s) in RCA: 87] [Impact Index Per Article: 8.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/17/2022]
Abstract
Lysosomes are acidic organelles essential for degradation, signalling and cell homoeostasis. In addition, they play a key role in cell death. Permeabilization of the lysosomal membrane and release of hydrolytic enzymes to the cytosol accompanies apoptosis signalling in several systems. The regulatory mechanism of lysosomal stability is, however, poorly understood. Lipophilic or amphiphilic compounds with a basic moiety will become protonated and trapped within lysosomes, and such lysosomotropic behaviour is also found in many pharmacological drugs. The natural sphingolipid sphingosine exhibits lysosomotropic detergent ability and is an endogenous candidate for controlling lysosomal membrane permeabilization. The lysosomotropic properties of certain detergents might be of use in lysosome-targeting anticancer drugs and drug delivery system in the future. The present review summarizes the current knowledge on the targeting and permeabilizing properties of lysosomotropic detergents from a cellular and physicochemical perspective.
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21
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Biophysical properties of sphingosine, ceramides and other simple sphingolipids. Biochem Soc Trans 2014; 42:1401-8. [DOI: 10.1042/bst20140159] [Citation(s) in RCA: 34] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/17/2022]
Abstract
Some of the simplest sphingolipids, namely sphingosine, ceramide and their phosphorylated compounds [sphingosine 1-phosphate (Sph-1-P) and ceramide 1-phosphate (Cer-1-P)], are potent metabolic regulators. Each of these lipids modifies in marked and specific ways the physical properties of the cell membranes, in what can be the basis for some of their physiological actions. The present paper is an overview of the mechanisms by which these sphingolipid signals, sphingosine and ceramide, in particular, are able to modify the properties of cell membranes.
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22
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Zupancic E, Carreira AC, de Almeida RFM, Silva LC. Biophysical Implications of Sphingosine Accumulation in Membrane Properties at Neutral and Acidic pH. J Phys Chem B 2014; 118:4858-66. [DOI: 10.1021/jp501167f] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Affiliation(s)
- Eva Zupancic
- iMed.UL
- Research Institute for Medicines and Pharmaceutical Sciences, Faculdade de Farmácia da Universidade de Lisboa, 1649-003 Lisboa, Portugal
| | - Ana C. Carreira
- iMed.UL
- Research Institute for Medicines and Pharmaceutical Sciences, Faculdade de Farmácia da Universidade de Lisboa, 1649-003 Lisboa, Portugal
- Centro
de Química e Bioquímica, DQB, Faculdade de Ciências da Universidade de Lisboa, Campo Grande, 1749-016 Lisboa, Portugal
| | - Rodrigo F. M. de Almeida
- Centro
de Química e Bioquímica, DQB, Faculdade de Ciências da Universidade de Lisboa, Campo Grande, 1749-016 Lisboa, Portugal
| | - Liana C. Silva
- iMed.UL
- Research Institute for Medicines and Pharmaceutical Sciences, Faculdade de Farmácia da Universidade de Lisboa, 1649-003 Lisboa, Portugal
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Truman JP, García-Barros M, Obeid LM, Hannun YA. Evolving concepts in cancer therapy through targeting sphingolipid metabolism. Biochim Biophys Acta Mol Cell Biol Lipids 2013; 1841:1174-88. [PMID: 24384461 DOI: 10.1016/j.bbalip.2013.12.013] [Citation(s) in RCA: 74] [Impact Index Per Article: 6.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/27/2013] [Revised: 12/18/2013] [Accepted: 12/21/2013] [Indexed: 12/29/2022]
Abstract
Traditional methods of cancer treatment are limited in their efficacy due to both inherent and acquired factors. Many different studies have shown that the generation of ceramide in response to cytotoxic therapy is generally an important step leading to cell death. Cancer cells employ different methods to both limit ceramide generation and to remove ceramide in order to become resistant to treatment. Furthermore, sphingosine kinase activity, which phosphorylates sphingosine the product of ceramide hydrolysis, has been linked to multidrug resistance, and can act as a strong survival factor. This review will examine several of the most frequently used cancer therapies and their effect on both ceramide generation and the mechanisms employed to remove it. The development and use of inhibitors of sphingosine kinase will be focused upon as an example of how targeting sphingolipid metabolism may provide an effective means to improve treatment response rates and reduce associated treatment toxicity. This article is part of a Special Issue entitled Tools to study lipid functions.
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Affiliation(s)
- Jean-Philip Truman
- Health Science Center, Stony Brook University, 100 Nicolls Road, T15, 023, 11794 Stony Brook, NY, USA.
| | - Mónica García-Barros
- Health Science Center, Stony Brook University, 100 Nicolls Road, T15, 023, 11794 Stony Brook, NY, USA.
| | - Lina M Obeid
- Northport Veterans Affairs Medical Center, Northport, NY 11768, USA; Health Science Center, Stony Brook University, 100 Nicolls Road, L4, 178, 11794 Stony Brook, NY, USA.
| | - Yusuf A Hannun
- Department of Medicine and the Stony Brook Cancer Center, Health Science Center, Stony Brook University, 100 Nicolls Road, L4, 178, 11794 Stony Brook, NY, USA.
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Andrographolide, a Novel NF- κ B Inhibitor, Induces Vascular Smooth Muscle Cell Apoptosis via a Ceramide-p47phox-ROS Signaling Cascade. EVIDENCE-BASED COMPLEMENTARY AND ALTERNATIVE MEDICINE 2013; 2013:821813. [PMID: 24489592 PMCID: PMC3893871 DOI: 10.1155/2013/821813] [Citation(s) in RCA: 27] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 10/30/2013] [Accepted: 12/04/2013] [Indexed: 12/15/2022]
Abstract
Atherosclerosis is linked with the development of many cardiovascular complications. Abnormal proliferation of vascular smooth muscle cells (VSMCs) plays a crucial role in the development of atherosclerosis. Accordingly, the apoptosis of VSMCs, which occurs in the progression of vascular proliferation, may provide a beneficial strategy for managing cardiovascular diseases. Andrographolide, a novel nuclear factor-κB inhibitor, is the most active and critical constituent isolated from the leaves of Andrographis paniculata. Recent studies have indicated that andrographolide is a potential therapeutic agent for treating cancer through the induction of apoptosis. In this study, the apoptosis-inducing activity and mechanisms in andrographolide-treated rat VSMCs were characterized. Andrographolide significantly induced reactive oxygen species (ROS) formation, p53 activation, Bax, and active caspase-3 expression, and these phenomena were suppressed by pretreating the cells with N-acetyl-L-cysteine, a ROS scavenger, or diphenylene iodonium, a nicotinamide adenine dinucleotide phosphate (NADPH) oxidase (Nox) inhibitor. Furthermore, p47phox, a Nox subunit protein, was phosphorylated in andrographolide-treated rat VSMCs. However, pretreatment with 3-O-methyl-sphingomyelin, a neutral sphingomyelinase inhibitor, significantly inhibited andrographolide-induced p47phox phosphorylation as well as Bax and active caspase-3 expression. Our results collectively demonstrate that andrographolide-reduced cell viability can be attributed to apoptosis in VSMCs, and this apoptosis-inducing activity was associated with the ceramide-p47phox-ROS signaling cascade.
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25
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Emerging roles of lipids in BCL-2 family-regulated apoptosis. Biochim Biophys Acta Mol Cell Biol Lipids 2013; 1831:1542-54. [DOI: 10.1016/j.bbalip.2013.03.001] [Citation(s) in RCA: 53] [Impact Index Per Article: 4.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/01/2013] [Revised: 02/28/2013] [Accepted: 03/02/2013] [Indexed: 01/06/2023]
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26
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Improving intracellular doxorubicin delivery through nanoliposomes equipped with selective tumor cell membrane permeabilizing short-chain sphingolipids. Pharm Res 2013; 30:1883-95. [PMID: 23666266 DOI: 10.1007/s11095-013-1031-6] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/01/2012] [Accepted: 03/12/2013] [Indexed: 10/26/2022]
Abstract
PURPOSE To improve nanoliposomal-doxorubicin (DoxNL) delivery in tumor cells using liposome membrane-incorporated short-chain sphingolipids (SCS) with selective membrane-permeabilizing properties. DoxNL bilayers contained synthetic short-chain derivatives of known membrane microdomain-forming sphingolipids; C₈-glucosylceramide (C₈-GluCer), C₈-galactosylceramide (C₈-GalCer) or C₈-lactosylceramide (C₈-LacCer). METHODS DoxNL enriched with C₈-GluCer or C₈-GalCer were developed, optimized and characterized with regard to size, stability and drug retention. In vitro cytotoxic activity was studied in a panel of human tumor cell lines and normal cells. Intracellular Dox delivery was measured by flow cytometry and visualized by fluorescence microscopy. For a further understanding of the involved drug delivery mechanism confocal microscopy studies addressed the cellular fate of the nanoliposomes, the SCS and Dox in living cells. RESULTS C₈-LacCer-DoxNL aggregated upon Dox loading. In tumor cell lines SCS-DoxNL with C₈-GluCer or C₈-GalCer demonstrated strongly increased Dox delivery and cytotoxicity compared to standard DoxNL. Surprisingly, this effect was much less pronounced in normal cells. Nanoliposomes were not internalized, SCS however transfered from the nanoliposomal bilayer to the cell membrane and preceded cellular uptake and subsequent nuclear localization of Dox. CONCLUSION C₈-GluCer or C₈-GalCer incorporated in DoxNL selectively improved intracellular drug delivery upon transfer to tumor cell membranes by local enhancement of cell membrane permeability.
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27
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Rego A, Costa M, Chaves SR, Matmati N, Pereira H, Sousa MJ, Moradas-Ferreira P, Hannun YA, Costa V, Côrte-Real M. Modulation of mitochondrial outer membrane permeabilization and apoptosis by ceramide metabolism. PLoS One 2012; 7:e48571. [PMID: 23226203 PMCID: PMC3511487 DOI: 10.1371/journal.pone.0048571] [Citation(s) in RCA: 47] [Impact Index Per Article: 3.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/23/2012] [Accepted: 09/28/2012] [Indexed: 01/28/2023] Open
Abstract
The yeast Saccharomyces cerevisiae undergoes a mitochondrial-dependent programmed cell death in response to different stimuli, such as acetic acid, with features similar to those of mammalian apoptosis. However, the upstream signaling events in this process, including those leading to mitochondrial membrane permeabilization, are still poorly characterized. Changes in sphingolipid metabolism have been linked to modulation of apoptosis in both yeast and mammalian cells, and ceramides have been detected in mitochondria upon apoptotic stimuli. In this study, we aimed to characterize the contribution of enzymes involved in ceramide metabolism to apoptotic cell death induced by acetic acid. We show that isc1Δ and lag1Δ mutants, lacking inositol phosphosphingolipid phospholipase C and ceramide synthase, respectively, exhibited a higher resistance to acetic acid that was associated with lower levels of some phytoceramide species. Consistently, these mutant cells displayed lower levels of ROS production and reduced mitochondrial alterations, such as mitochondrial fragmentation and degradation, and decreased translocation of cytochrome c into the cytosol in response to acetic acid. These results suggest that ceramide production contributes to cell death induced by acetic acid, especially through hydrolysis of complex sphingolipids catalyzed by Isc1p and de novo synthesis catalyzed by Lag1p, and provide the first in vivo indication of its involvement in mitochondrial outer membrane permeabilization in yeast.
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Affiliation(s)
- António Rego
- Departamento de Biologia, Centro de Biologia Molecular e Ambiental, Universidade do Minho, Braga, Portugal
- Instituto de Biologia Molecular e Celular, Universidade do Porto, Porto, Portugal
| | - Margarida Costa
- Instituto de Biologia Molecular e Celular, Universidade do Porto, Porto, Portugal
- Departamento de Biologia Molecular, Instituto de Ciências Biomédicas Abel Salazar, Universidade do Porto, Porto, Portugal
| | - Susana Rodrigues Chaves
- Departamento de Biologia, Centro de Biologia Molecular e Ambiental, Universidade do Minho, Braga, Portugal
| | - Nabil Matmati
- Stony Brook Cancer Center, Stony Brook University, Health Science Center, Stony Brook, New York, United States of America
| | - Helena Pereira
- Departamento de Biologia, Centro de Biologia Molecular e Ambiental, Universidade do Minho, Braga, Portugal
| | - Maria João Sousa
- Departamento de Biologia, Centro de Biologia Molecular e Ambiental, Universidade do Minho, Braga, Portugal
| | - Pedro Moradas-Ferreira
- Instituto de Biologia Molecular e Celular, Universidade do Porto, Porto, Portugal
- Departamento de Biologia Molecular, Instituto de Ciências Biomédicas Abel Salazar, Universidade do Porto, Porto, Portugal
| | - Yusuf A. Hannun
- Stony Brook Cancer Center, Stony Brook University, Health Science Center, Stony Brook, New York, United States of America
| | - Vítor Costa
- Instituto de Biologia Molecular e Celular, Universidade do Porto, Porto, Portugal
- Departamento de Biologia Molecular, Instituto de Ciências Biomédicas Abel Salazar, Universidade do Porto, Porto, Portugal
- * E-mail: (VC); (MCR)
| | - Manuela Côrte-Real
- Departamento de Biologia, Centro de Biologia Molecular e Ambiental, Universidade do Minho, Braga, Portugal
- * E-mail: (VC); (MCR)
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Young MM, Kester M, Wang HG. Sphingolipids: regulators of crosstalk between apoptosis and autophagy. J Lipid Res 2012; 54:5-19. [PMID: 23152582 DOI: 10.1194/jlr.r031278] [Citation(s) in RCA: 265] [Impact Index Per Article: 22.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/23/2022] Open
Abstract
Apoptosis and autophagy are two evolutionarily conserved processes that maintain homeostasis during stress. Although the two pathways utilize fundamentally distinct machinery, apoptosis and autophagy are highly interconnected and share many key regulators. The crosstalk between apoptosis and autophagy is complex, as autophagy can function to promote cell survival or cell death under various cellular conditions. The molecular mechanisms of crosstalk are beginning to be elucidated and have critical implications for the treatment of various diseases, such as cancer. Sphingolipids are a class of bioactive lipids that mediate many key cellular processes, including apoptosis and autophagy. By targeting several of the shared regulators, sphingolipid metabolites differentially regulate the induction of apoptosis and autophagy. Importantly, individual sphingolipid species appear to "switch" autophagy toward cell survival (e.g., sphingosine-1-phosphate) or cell death (e.g., ceramide, gangliosides). This review assesses the current understanding of sphingolipid-induced apoptosis and autophagy to address how sphingolipids mediate the "switch" between the cell survival and cell death. As sphingolipid metabolism is frequently dysregulated in cancer, sphingolipid-modulating agents, or sphingomimetics, have emerged as a novel chemotherapeutic strategy. Ultimately, a greater understanding of sphingolipid-mediated crosstalk between apoptosis and autophagy may be critical for enhancing the chemotherapeutic efficacy of these agents.
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Affiliation(s)
- Megan M Young
- Department of Pharmacology and Penn State Hershey Cancer Institute, Pennsylvania State University College of Medicine, Hershey, PA, USA
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29
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Affiliation(s)
- Marco Colombini
- Department of Biology,
University of Maryland, College
Park, Maryland 20742, United States
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30
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Shao C, Sun B, DeVoe DL, Colombini M. Dynamics of ceramide channels detected using a microfluidic system. PLoS One 2012; 7:e43513. [PMID: 22984432 PMCID: PMC3440423 DOI: 10.1371/journal.pone.0043513] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/28/2012] [Accepted: 07/25/2012] [Indexed: 01/15/2023] Open
Abstract
Ceramide, a proapoptotic sphingolipid, has been shown to form channels, in mitochondrial outer membranes, large enough to translocate proteins. In phospholipid membranes, electrophysiological studies and electron microscopic visualization both report that these channels form in a range of sizes with a modal value of 10 nm in diameter. A hydrogen bonded barrel-like structure consisting of hundreds of ceramide molecules has been proposed for the structure of the channel and this is supported by electrophysiological studies and molecular dynamic simulations. To our knowledge, the mechanical strength and deformability of such a large diameter but extremely thin cylindrical structure has never been reported. Here we present evidence for a reversible mechanical distortion of the cylinder following the addition of La3+. A microfluidic system was used to repeatedly lower and then restore the conductance by alternatively perfusing La3+ and EDTA. Although aspects of the kinetics of conductance drop and recovery are consistent with a disassembly/diffusion/reassembly model, others are inconsistent with the expected time scale of lateral diffusion of disassembled channel fragments in the membrane. The presence of a residual conductance following La3+ treatment and the relationship between the residual conductance and the initial conductance were both indicative of a distortion/recovery process in analogy with a pressure-induced distortion of a flexible cylinder.
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Affiliation(s)
- Chenren Shao
- Department of Mechanical Engineering, University of Maryland, College Park, Maryland, United States of America
| | - Bing Sun
- Department of Biology, University of Maryland, College Park, Maryland, United States of America
| | - Don L. DeVoe
- Department of Mechanical Engineering, University of Maryland, College Park, Maryland, United States of America
| | - Marco Colombini
- Department of Biology, University of Maryland, College Park, Maryland, United States of America
- * E-mail:
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31
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Laub KR, Witschas K, Blicher A, Madsen SB, Lückhoff A, Heimburg T. Comparing ion conductance recordings of synthetic lipid bilayers with cell membranes containing TRP channels. BIOCHIMICA ET BIOPHYSICA ACTA-BIOMEMBRANES 2012; 1818:1123-34. [PMID: 22305677 DOI: 10.1016/j.bbamem.2012.01.014] [Citation(s) in RCA: 23] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/14/2011] [Revised: 12/23/2011] [Accepted: 01/17/2012] [Indexed: 10/14/2022]
Abstract
In this article we compare electrical conductance events from single channel recordings of three TRP channel proteins (TRPA1, TRPM2 and TRPM8) expressed in human embryonic kidney cells with channel events recorded on synthetic lipid membranes close to melting transitions. Ion channels from the TRP family are involved in a variety of sensory processes including thermo- and mechano-reception. Synthetic lipid membranes close to phase transitions display channel-like events that respond to stimuli related to changes in intensive thermodynamic variables such as pressure and temperature. TRP channel activity is characterized by typical patterns of current events dependent on the type of protein expressed. Synthetic lipid bilayers show a wide spectrum of electrical phenomena that are considered typical for the activity of protein ion channels. We find unitary currents, burst behavior, flickering, multistep-conductances, and spikes behavior in both preparations. Moreover, we report conductances and lifetimes for lipid channels as described for protein channels. Non-linear and asymmetric current-voltage relationships are seen in both systems. Without further knowledge of the recording conditions, no easy decision can be made whether short current traces originate from a channel protein or from a pure lipid membrane.
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Affiliation(s)
- Katrine R Laub
- Membrane Biophysics Group, Niels Bohr Institute, University of Copenhagen, Denmark
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32
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Shao C, Sun B, Colombini M, Devoe DL. Rapid microfluidic perfusion enabling kinetic studies of lipid ion channels in a bilayer lipid membrane chip. Ann Biomed Eng 2011; 39:2242-51. [PMID: 21556947 DOI: 10.1007/s10439-011-0323-4] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/15/2011] [Accepted: 05/02/2011] [Indexed: 01/23/2023]
Abstract
There is growing recognition that lipids play key roles in ion channel physiology, both through the dynamic formation and dissolution of lipid ion channels and by indirect regulation of protein ion channels. Because existing technologies cannot rapidly modulate the local (bio)chemical conditions at artificial bilayer lipid membranes used in ion channel studies, the ability to elucidate the dynamics of these lipid-lipid and lipid-protein interactions has been limited. Here we demonstrate a microfluidic system supporting exceptionally rapid perfusion of reagents to an on-chip bilayer lipid membrane, enabling the responses of lipid ion channels to dynamic changes in membrane boundary conditions to be probed. The thermoplastic microfluidic system allows initial perfusion of reagents to the membrane in less than 1 s, and enables kinetic behaviors with time constants below 10 s to be directly measured. Application of the platform is demonstrated toward kinetic studies of ceramide, a biologically important lipid known to self-assemble into transmembrane ion channels, in response to dynamic treatments of small ions (La(3+)) and proteins (Bcl-x(L) mutant). The results reveal the broader potential of the technology for studies of membrane biophysics, including lipid ion channel dynamics, lipid-protein interactions, and the regulation of protein ion channels by lipid micro domains.
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Affiliation(s)
- Chenren Shao
- Department of Mechanical Engineering, University of Maryland, College Park, MD 20742, USA
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33
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Ma R, Hopp EA, Decker NM, Loucks A, Johnson JR, Moskal J, Basu M, Banerjee S, Basu S. Regulation of Glycosyltransferase Genes in Apoptotic Breast Cancer Cells Induced by l-PPMP and Cisplatin. ADVANCES IN EXPERIMENTAL MEDICINE AND BIOLOGY 2011; 705:621-42. [DOI: 10.1007/978-1-4419-7877-6_33] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 02/10/2023]
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Parent N, Scherer M, Liebisch G, Schmitz G, Bertrand R. Protein kinase C-δ isoform mediates lysosome labilization in DNA damage-induced apoptosis. Int J Oncol 2010; 38:313-24. [PMID: 21174057 DOI: 10.3892/ijo.2010.881] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/22/2010] [Accepted: 11/05/2010] [Indexed: 11/05/2022] Open
Abstract
A lysosomal pathway, characterized by the partial rupture or labilization of lysosomal membranes (LLM) and cathepsin release into the cytosol, is evoked during the early events of 20-S-camptothecin lactone (CPT)-induced apoptosis in human cancer cells, including human histiocytic lymphoma U-937 cells. These lysosomal events begin rapidly and simultaneously with mitochondrial permeabilization and caspase activation within 3 h after drug treatment. Recently, in a comparative proteomics analysis performed on highly-enriched lysosomal extracts, we identified proteins whose translocation to lysosomes correlated with LLM induction after CPT treatment, including protein kinase C-δ (PKC-δ). In this study, we show that the PKC-δ translocation to lysosomes is required for LLM, as silencing its expression with RNA interference or suppressing its activity with the inhibitor, rottlerin, prevents CPT-induced LLM. PKC-δ translocation to lysosomes is associated with lysosomal acidic sphingomyelinase (ASM) phosphorylation and activation, which in turn leads to an increase in ceramide (CER) content in lysosomes. The accumulation of endogenous CER in lysosomes is a critical event for CPT-induced LLM as suppressing PKC-δ or ASM activity reduces both the CPT-mediated CER generation in lysosomes and CPT-induced LLM. These findings reveal a novel mechanism by which PKC-δ mediates ASM phosphorylation/activation and CER accumulation in lysosomes in CPT-induced LLM, rapidly activating the lysosomal pathway of apoptosis after CPT treatment.
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Affiliation(s)
- Nicolas Parent
- Centre de Recherche du Centre Hospitalier de l'Université de Montréal, Hôpital Notre-Dame and Institut du Cancer de Montréal, Montreal, QC H2L 4M1, Canada
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35
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Lummel M, Blitterswijk WJ, Vink SR, Veldman RJ, Valk MA, Schipper D, Dicheva BM, Eggermont AMM, Hagen TLMT, Verheij M, Koning GA. Enriching lipid nanovesicles with short‐chain glucosylceramide improves doxorubicin delivery and efficacy in solid tumors. FASEB J 2010; 25:280-9. [DOI: 10.1096/fj.10-163709] [Citation(s) in RCA: 46] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/04/2023]
Affiliation(s)
- Menno Lummel
- Department of Cellular BiochemistryThe Netherlands Cancer Institute‐Antoni van Leeuwenhoek HospitalAmsterdamThe Netherlands
| | - Wim J. Blitterswijk
- Department of Cellular BiochemistryThe Netherlands Cancer Institute‐Antoni van Leeuwenhoek HospitalAmsterdamThe Netherlands
| | - Stefan R. Vink
- Department of Cellular BiochemistryThe Netherlands Cancer Institute‐Antoni van Leeuwenhoek HospitalAmsterdamThe Netherlands
| | - Robert Jan Veldman
- Department of Cellular BiochemistryThe Netherlands Cancer Institute‐Antoni van Leeuwenhoek HospitalAmsterdamThe Netherlands
| | - Martin A. Valk
- Laboratory of Experimental Animal PathologyThe Netherlands Cancer Institute‐Antoni van Leeuwenhoek HospitalAmsterdamThe Netherlands
| | - Debby Schipper
- Laboratory of Experimental Surgical OncologySection of Surgical OncologyDepartment of SurgeryErasmus Medical CenterRotterdamThe Netherlands
| | - Bilyana M. Dicheva
- Laboratory of Experimental Surgical OncologySection of Surgical OncologyDepartment of SurgeryErasmus Medical CenterRotterdamThe Netherlands
| | - Alexander M. M. Eggermont
- Laboratory of Experimental Surgical OncologySection of Surgical OncologyDepartment of SurgeryErasmus Medical CenterRotterdamThe Netherlands
| | - Timo L. M. ten Hagen
- Laboratory of Experimental Surgical OncologySection of Surgical OncologyDepartment of SurgeryErasmus Medical CenterRotterdamThe Netherlands
| | - Marcel Verheij
- Department of Cellular BiochemistryThe Netherlands Cancer Institute‐Antoni van Leeuwenhoek HospitalAmsterdamThe Netherlands
- Department of Radiation OncologyThe Netherlands Cancer Institute‐Antoni van Leeuwenhoek HospitalAmsterdamThe Netherlands
| | - Gerben A. Koning
- Laboratory of Experimental Surgical OncologySection of Surgical OncologyDepartment of SurgeryErasmus Medical CenterRotterdamThe Netherlands
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36
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Ganesan V, Colombini M. Regulation of ceramide channels by Bcl-2 family proteins. FEBS Lett 2010; 584:2128-34. [PMID: 20159016 DOI: 10.1016/j.febslet.2010.02.032] [Citation(s) in RCA: 39] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/06/2010] [Revised: 02/09/2010] [Accepted: 02/10/2010] [Indexed: 02/05/2023]
Abstract
Mitochondrial outer membrane permeabilization to proteins, an irreversible step in apoptosis by which critical proteins are released, is tightly regulated by Bcl-2 family proteins. The exact nature of the release pathway is still undefined. Ceramide is an important sphingolipid, involved in various cellular processes including apoptosis. Here we describe the structural properties of ceramide channels and their regulation by the anti-apoptotic and pro-apoptotic proteins of the Bcl-2 family. The evolutionarily conserved regulation of ceramide channels by Bcl-2 family proteins, consistent with their role in apoptosis, lends credibility to the notion that ceramide channels constitute the protein release pathway.
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37
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Ganesan V, Perera MN, Colombini D, Datskovskiy D, Chadha K, Colombini M. Ceramide and activated Bax act synergistically to permeabilize the mitochondrial outer membrane. Apoptosis 2010; 15:553-62. [DOI: 10.1007/s10495-009-0449-0] [Citation(s) in RCA: 100] [Impact Index Per Article: 7.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/19/2022]
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38
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Ceramide channels and their role in mitochondria-mediated apoptosis. BIOCHIMICA ET BIOPHYSICA ACTA-BIOENERGETICS 2010; 1797:1239-44. [PMID: 20100454 DOI: 10.1016/j.bbabio.2010.01.021] [Citation(s) in RCA: 89] [Impact Index Per Article: 6.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/23/2009] [Revised: 01/07/2010] [Accepted: 01/14/2010] [Indexed: 11/20/2022]
Abstract
A key, decision-making step in apoptosis is the release of proteins from the mitochondrial intermembrane space. Ceramide can self-assemble in the mitochondrial outer membrane to form large stable channels capable of releasing said proteins. Ceramide levels measured in mitochondria early in apoptosis are sufficient to form ceramide channels in the outer membrane. The channels are in dynamic equilibrium with non-conducting forms of ceramide in the membrane. This equilibrium can be strongly influenced by other sphingolipids and Bcl-2 family proteins. The properties of ceramide channels formed in a defined system, planar phospholipid membranes, demonstrate that proteins are not required for channel formation. In addition, experiments in the defined system reveal structural information. The results indicated that the channels are barrel-like structures whose staves are ceramide columns that span the membrane. Ceramide channels are good candidates for the protein release pathway that initiates the execution phase of apoptosis.
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39
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Lipid oversupply, selective insulin resistance, and lipotoxicity: molecular mechanisms. Biochim Biophys Acta Mol Cell Biol Lipids 2009; 1801:252-65. [PMID: 19796706 DOI: 10.1016/j.bbalip.2009.09.015] [Citation(s) in RCA: 125] [Impact Index Per Article: 8.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/08/2009] [Revised: 09/16/2009] [Accepted: 09/17/2009] [Indexed: 12/15/2022]
Abstract
The accumulation of fat in tissues not suited for lipid storage has deleterious consequences on organ function, leading to cellular damage that underlies diabetes, heart disease, and hypertension. To combat these lipotoxic events, several therapeutics improve insulin sensitivity and/or ameliorate features of metabolic disease by limiting the inappropriate deposition of fat in peripheral tissues (i.e. thiazolidinediones, metformin, and statins). Recent advances in genomics and lipidomics have accelerated progress towards understanding the pathogenic events associated with the excessive production, underutilization, or inefficient storage of fat. Herein we review studies applying pharmacological or genetic strategies to manipulate the expression or activity of enzymes controlling lipid deposition, in order to gain a clearer understanding of the molecular mechanisms by which fatty acids contribute to metabolic disease.
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40
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Quijano JC, Lemeshko VV. Hemoglobin precipitation by polyethylene glycols leads to underestimation of membrane pore sizes. BIOCHIMICA ET BIOPHYSICA ACTA-BIOMEMBRANES 2008; 1778:2775-80. [DOI: 10.1016/j.bbamem.2008.07.009] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/07/2008] [Revised: 07/12/2008] [Accepted: 07/15/2008] [Indexed: 11/17/2022]
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41
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Holland WL, Summers SA. Sphingolipids, insulin resistance, and metabolic disease: new insights from in vivo manipulation of sphingolipid metabolism. Endocr Rev 2008; 29:381-402. [PMID: 18451260 PMCID: PMC2528849 DOI: 10.1210/er.2007-0025] [Citation(s) in RCA: 428] [Impact Index Per Article: 26.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 12/12/2022]
Abstract
Obesity and dyslipidemia are risk factors for metabolic disorders including diabetes and cardiovascular disease. Sphingolipids such as ceramide and glucosylceramides, while being a relatively minor component of the lipid milieu in most tissues, may be among the most pathogenic lipids in the onset of the sequelae associated with excess adiposity. Circulating factors associated with obesity (e.g., saturated fatty acids, inflammatory cytokines) selectively induce enzymes that promote sphingolipid synthesis, and lipidomic profiling reveals relationships between tissue sphingolipid levels and certain metabolic diseases. Moreover, studies in cultured cells and isolated tissues implicate sphingolipids in certain cellular events associated with diabetes and cardiovascular disease, including insulin resistance, pancreatic beta-cell failure, cardiomyopathy, and vascular dysfunction. However, definitive evidence that sphingolipids contribute to insulin resistance, diabetes, and atherosclerosis has come only recently, as researchers have found that pharmacological inhibition or genetic ablation of enzymes controlling sphingolipid synthesis in rodents ameliorates each of these conditions. Herein we will review the role of ceramide and other sphingolipid metabolites in insulin resistance, beta-cell failure, cardiomyopathy, and vascular dysfunction, focusing on these in vivo studies that identify enzymes controlling sphingolipid metabolism as therapeutic targets for combating metabolic disease.
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Affiliation(s)
- William L Holland
- Division of Endocrinology, Metabolism, and Diabetes, Department of Internal Medicine, University of Utah, Salt Lake City, Utah 84132, USA
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42
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Abstract
Sphingolipids (SLs) have been considered for many years as predominant building blocks of biological membranes with key structural functions and little relevance in cellular signaling. However, this view has changed dramatically in recent years with the recognition that certain SLs such as ceramide, sphingosine 1-phosphate and gangliosides, participate actively in signal transduction pathways, regulating many different cell functions such as proliferation, differentiation, adhesion and cell death. In particular, ceramide has attracted considerable attention in cell biology and biophysics due to its key role in the modulation of membrane physical properties, signaling and cell death regulation. This latter function is largely exerted by the ability of ceramide to activate the major pathways governing cell death such as the endoplasmic reticulum and mitochondria. Overall, the evidence so far indicates a key function of SLs in disease pathogenesis and hence their regulation may be of potential therapeutic relevance in different pathologies including liver diseases, neurodegeneration and cancer biology and therapy.
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Affiliation(s)
- Albert Morales
- Liver Unit and Centro de Investigaciones Biomédicas Esther Koplowitz, IMDiM, Hospital, Clínic i Provincial, Instituto Investigaciones Biomédicas August Pi i Sunyer (IDIBAPS), 08036 Barcelona, Spain
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43
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Stiban J, Caputo L, Colombini M. Ceramide synthesis in the endoplasmic reticulum can permeabilize mitochondria to proapoptotic proteins. J Lipid Res 2007; 49:625-34. [PMID: 18073406 DOI: 10.1194/jlr.m700480-jlr200] [Citation(s) in RCA: 114] [Impact Index Per Article: 6.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022] Open
Abstract
Increased mitochondrial ceramide levels are associated with the initiation of apoptosis. There is evidence that ceramide is causal. Thus, the conversion of the precursor, dihydroceramide, to ceramide by the enzyme dihydroceramide desaturase may be important in preparing the cell for apoptosis. Ceramide can initiate apoptosis by permeabilizing the mitochondrial outer membrane to apoptosis-inducing proteins. However, the mitochondrion's ability to produce ceramide may be limited by its proteome. Here, we show that ceramide synthesized in isolated mammalian endoplasmic reticulum (ER) vesicles from either C8-dihydroceramide or sphingosine to produce long-chain ceramide can transfer to isolated mitochondria. The rate of transfer is consistent with a simple collision model. The transfer of the long-chain ceramide is faster than expected for an uncatalyzed process. Sufficient ceramide is transferred to permeabilize the outer membrane to cytochrome c and adenylate kinase. The mitochondria-associated membranes, ER-like membranes that are tightly associated with isolated mitochondria, can produce enough ceramide to permeabilize the outer membrane transiently. Thus, this ceramide exchange obviates the need for a complete ceramide de novo pathway in mitochondria to increase ceramide levels to the critical value required for functional changes, such as ceramide channel self-assembly followed by protein release.
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Affiliation(s)
- Johnny Stiban
- Department of Biology, University of Maryland, College Park, MD 20742, USA
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44
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Leroux ME, Auzenne E, Evans R, Hail N, Spohn W, Ghosh SC, Farquhar D, McDonnell T, Klostergaard J. Sphingolipids and the sphingosine kinase inhibitor, SKI II, induce BCL-2-independent apoptosis in human prostatic adenocarcinoma cells. Prostate 2007; 67:1699-717. [PMID: 17879964 DOI: 10.1002/pros.20645] [Citation(s) in RCA: 29] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 01/23/2023]
Abstract
BACKGROUND Elevated BCL-2 is one mechanism of therapeutic resistance in prostate cancer (PC), and new approaches are needed to overcome such resistance. METHODS We evaluated the effects of BCL-2 over-expression in human prostatic adenocarcinoma cells on their susceptibility to sphingolipids (SLs) and to the sphingosine kinase (SpK) inhibitor, SKI II. RESULTS In survival assays, no significant differences were observed in the responses to sphingosine or ceramide among parental PC-3 cells lacking detectable BCL-2 and BCL-2 over-expressing PC-3 transfectants; similarly, the responses to dimethyl-sphingosine (DMSP) of parental LNCaP cells and a BCL-2 over-expressing LNCaP transfectant were equivalent. SKI II induced protracted, BCL-2-independent survival loss in both PC-3 and LNCaP parental/transfectant pairs; in contrast, DMSP induced rapid cell shrinkage, caspase activation and caspase-dependent DNA fragmentation. DMSP-induced DNA fragmentation and loss of mitochondrial membrane potential were equivalent in BCL-2 transfectants and parental PC-3 cells and were not associated with BCL-2 downregulation. DMSP-mediated cytotoxicity was not associated with the enhanced production of reactive oxygen intermediates. SL analyses of parental and transfectant PC-3 cells did not reveal increased levels of sphingosine-1-phosphate in the BCL-2 transfectants; further, there only a modest early shift, corresponding to apoptotic onset, in pro- versus anti-apoptotic SLs in response to DMSP treatment. CONCLUSIONS Thus, in contrast to the inhibitory effects of BCL-2 on apoptosis induced by various agents in tumor cells, SKI II and selected pro-apoptotic SLs appear atypical in their independence from such inhibition, and may have merits as new candidates for treatment of AI PC.
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Affiliation(s)
- M E Leroux
- Department of Molecular and Cellular Oncology, The University of Texas, MD Anderson Cancer Center, Houston, TX 77030, USA
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45
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Abstract
Ceramides are ubiquitous lipids that have important functions integral to apoptotic signaling. Several therapeutic agents currently exist that induce ceramide-dependent apoptosis in cancerous cells, and a number of enzymes involved in ceramide metabolism are beginning to be recognized as potential targets for cancer therapy. Recent research shows that evasion of ceramide-dependent apoptosis is essential at the earliest stages of embryonic development and is an important mechanism of multidrug resistance. Although ceramide-based strategies for treating cancer are promising, current data about ceramide-resistant tumors require further understanding of the role of ceramide in apoptosis.
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Affiliation(s)
- Iaroslav A Savtchouk
- Department of Biology, Pennsylvania State University, University Park, PA 16802, USA.
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46
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Skommer J, Wlodkowic D, Deptala A. Larger than life: Mitochondria and the Bcl-2 family. Leuk Res 2007; 31:277-86. [PMID: 16911824 DOI: 10.1016/j.leukres.2006.06.027] [Citation(s) in RCA: 65] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/03/2006] [Revised: 06/04/2006] [Accepted: 06/16/2006] [Indexed: 01/09/2023]
Abstract
The intrinsic pathway of apoptosis relies on mitochondrial membrane permeabilization, with Bcl-2 proteins serving as its master regulators. They form a complex network of interactions both within the family and with multiple cellular factors outside the family. The understanding of the processes that regulate mitochondrial breach, and mechanisms that direct the pro- and anti-apoptotic functions of Bcl-2 proteins, should assist the development of novel anticancer therapies. Thus, it is of no surprise that research in the field is gaining momentum. In this review we outline the current concepts on regulatory circuits governing mitochondrial rupture and action of Bcl-2 proteins during cell death, and how this burgeoning knowledge is being translated into the clinics with the hope to combat cancer.
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Affiliation(s)
- Joanna Skommer
- Department of Clinical Sciences, University of Kuopio, Harjulantie 1 C, 70211 Kuopio, Finland.
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Goñi FM, Alonso A. Biophysics of sphingolipids I. Membrane properties of sphingosine, ceramides and other simple sphingolipids. BIOCHIMICA ET BIOPHYSICA ACTA-BIOMEMBRANES 2006; 1758:1902-21. [PMID: 17070498 DOI: 10.1016/j.bbamem.2006.09.011] [Citation(s) in RCA: 206] [Impact Index Per Article: 11.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Subscribe] [Scholar Register] [Received: 06/09/2006] [Revised: 09/15/2006] [Accepted: 09/18/2006] [Indexed: 12/16/2022]
Abstract
Some of the simplest sphingolipids, namely sphingosine, ceramide, some closely related molecules (eicosasphingosine, phytosphingosine), and their phosphorylated compounds (sphingosine-1-phosphate, ceramide-1-phosphate), are potent metabolic regulators. Each of these lipids modifies in marked and specific ways the physical properties of the cell membranes, in what can be the basis for some of their physiological actions. This paper reviews the mechanisms by which these sphingolipid signals, sphingosine and ceramide in particular, are able to modify the properties of cell membranes.
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Affiliation(s)
- Félix M Goñi
- Unidad de Biofísica (Centro Mixto CSIC-UPV/EHU), Departamento de Bioquímica, Universidad del País Vasco, Aptdo. 644, 48080 Bilbao, Spain.
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Zheng W, Kollmeyer J, Symolon H, Momin A, Munter E, Wang E, Kelly S, Allegood JC, Liu Y, Peng Q, Ramaraju H, Sullards MC, Cabot M, Merrill AH. Ceramides and other bioactive sphingolipid backbones in health and disease: lipidomic analysis, metabolism and roles in membrane structure, dynamics, signaling and autophagy. BIOCHIMICA ET BIOPHYSICA ACTA-BIOMEMBRANES 2006; 1758:1864-84. [PMID: 17052686 DOI: 10.1016/j.bbamem.2006.08.009] [Citation(s) in RCA: 421] [Impact Index Per Article: 23.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Subscribe] [Scholar Register] [Received: 07/27/2006] [Accepted: 08/16/2006] [Indexed: 12/14/2022]
Abstract
Sphingolipids are comprised of a backbone sphingoid base that may be phosphorylated, acylated, glycosylated, bridged to various headgroups through phosphodiester linkages, or otherwise modified. Organisms usually contain large numbers of sphingolipid subspecies and knowledge about the types and amounts is imperative because they influence membrane structure, interactions with the extracellular matrix and neighboring cells, vesicular traffic and the formation of specialized structures such as phagosomes and autophagosomes, as well as participate in intracellular and extracellular signaling. Fortunately, "sphingolipidomic" analysis is becoming feasible (at least for important subsets such as all of the backbone "signaling" subspecies: ceramides, ceramide 1-phosphates, sphingoid bases, sphingoid base 1-phosphates, inter alia) using mass spectrometry, and these profiles are revealing many surprises, such as that under certain conditions cells contain significant amounts of "unusual" species: N-mono-, di-, and tri-methyl-sphingoid bases (including N,N-dimethylsphingosine); 3-ketodihydroceramides; N-acetyl-sphingoid bases (C2-ceramides); and dihydroceramides, in the latter case, in very high proportions when cells are treated with the anticancer drug fenretinide (4-hydroxyphenylretinamide). The elevation of DHceramides by fenretinide is befuddling because the 4,5-trans-double bond of ceramide has been thought to be required for biological activity; however, DHceramides induce autophagy and may be important in the regulation of this important cellular process. The complexity of the sphingolipidome is hard to imagine, but one hopes that, when partnered with other systems biology approaches, the causes and consequences of the complexity will explain how these intriguing compounds are involved in almost every aspect of cell behavior and the malfunctions of many diseases.
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Affiliation(s)
- Wenjing Zheng
- School of Biology, Chemistry and Biochemistry, Petit Institute of Bioengineering and Bioscience, Georgia Institute of Technology, Atlanta, GA 30332-0230, USA
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Elrick MJ, Fluss S, Colombini M. Sphingosine, a product of ceramide hydrolysis, influences the formation of ceramide channels. Biophys J 2006; 91:1749-56. [PMID: 16782799 PMCID: PMC1544278 DOI: 10.1529/biophysj.106.088443] [Citation(s) in RCA: 32] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/19/2022] Open
Abstract
Ceramides are known to have a regulatory function in apoptosis, including the release of cytochrome c and other proapoptotic factors from the mitochondrial intermembrane space. Ceramides can form large, stable channels in the outer mitochondrial membrane, leading to the proposal that ceramide channels are the pathway through which these proteins are released. Here, we report that sphingosine, a product of ceramide hydrolysis by ceramidase, is capable of destabilizing ceramide channels, leading to their disassembly. Sphingosine is directly responsible for the disassembly of ceramide channels in planar membrane experiments and markedly reduces the ability of ceramide to induce the release of intermembrane space proteins from mitochondria in vitro. Low concentrations of both L and D sphingosine potentiate the release of intermembrane space proteins by long-chain ceramide and channel formation in liposomes. These results provide evidence for a mechanism by which the disassembly of ceramide channels, as initiated by ceramidase, could be accelerated by the direct interaction of the hydrolysis product with the ceramide channels themselves. This mechanism therefore could form a positive feedback loop for rapid shut-down of ceramide channels. However, potentiation of ceramide channel formation is also possible and thus both effects could influence the propensity for mitochondria-mediated apoptosis.
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Affiliation(s)
- Matthew J Elrick
- Department of Biology, University of Maryland, College Park, Maryland 20742, USA
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Abstract
This critical review covers synthetic ion channels and pores created between January 2004 and December 2005 comprehensively. The discussion of a rich collection of structural motifs may particularly appeal to organic, biological, supramolecular and polymer chemists. Functions addressed include ion selectivity and molecular recognition, as well as responsiveness to light, heat, voltage and membrane composition. The practical applications involved concern certain topics in medicinal chemistry (antibiotics, drug delivery), catalysis and sensing. An introduction to principles and methods is provided for the non-specialist; some new sources of inspiration from fields beyond chemistry are highlighted.
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Affiliation(s)
- Adam L Sisson
- Department of Organic Chemistry, University of Geneva, Geneva, Switzerland
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