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Schneider Alves AC, Cardoso RS, de Oliveira Neto XA, Kawano DF. Uncovering the Potential of Lipid Drugs: A Focus on Transient Membrane Microdomain-Targeted Lipid Therapeutics. Mini Rev Med Chem 2022; 22:2318-2331. [PMID: 35264091 DOI: 10.2174/1389557522666220309162203] [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: 10/04/2021] [Revised: 10/27/2021] [Accepted: 01/27/2022] [Indexed: 11/22/2022]
Abstract
Membrane lipids are generally viewed as inert physical barriers, but many vital cellular processes greatly rely on the interaction with these structures, as expressed by the membrane hypothesis that explain the genesis of schizophrenia, Alzheimer's and autoimmune diseases, chronic fatigue or cancer, among others. The concept that the cell membrane displays transient membrane microdomains with distinct lipid composition provide the basis for the development of selective lipid-targeted therapies, the membrane-lipid therapies (MLTs). In this concern, medicinal chemists may design therapeutically valuable compounds 1) with a higher affinity for the lipids in these microdomains to restore the normal physiological conditions, 2) that can directly or 3) indirectly (via enzyme inhibition/activation) replace damaged lipids or restore the regular lipid levels in the whole membrane or microdomain, 4) that alter the expression of genes related to lipid genesis/metabolism or 5) that modulate the pathways related to the membrane binding affinity of lipid-anchored proteins. In this context, this mini-review aims to explore the structural diversity and clinical applications of some of the main membrane and microdomain-targeted lipid drugs.
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Affiliation(s)
- Anna Carolina Schneider Alves
- Faculty of Pharmaceutical Sciences, University of Campinas - UNICAMP 200 Cândido Portinari Street, Campinas, SP 13083871. Brazil
| | - Raquel Soares Cardoso
- Faculty of Pharmaceutical Sciences, University of Campinas - UNICAMP. 200 Cândido Portinari Street, Campinas, SP 13083871. Brazil
| | - Xisto Antonio de Oliveira Neto
- Faculty of Pharmaceutical Sciences, University of Campinas - UNICAMP. 200 Cândido Portinari Street, Campinas, SP 13083871. Brazil
| | - Daniel Fábio Kawano
- Faculty of Pharmaceutical Sciences, University of Campinas - UNICAMP. 200 Cândido Portinari Street, Campinas, SP 13083871. Brazil
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2
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Molecular Docking Reveals the Binding Modes of Anticancer Alkylphospholipids and Lysophosphatidylcholine within the Catalytic Domain of Cytidine Triphosphate: Phosphocholine Cytidyltransferase. EUR J LIPID SCI TECH 2020. [DOI: 10.1002/ejlt.201900422] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/26/2022]
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3
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Barrias E, Reignault LC, Calogeropoulou T, de Souza W. In vitro activities of adamantylidene-substituted alkylphosphocholine TCAN26 against Trypanosoma cruzi: Antiproliferative and ultrastructural effects. Exp Parasitol 2019; 206:107730. [PMID: 31494215 DOI: 10.1016/j.exppara.2019.107730] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/11/2018] [Revised: 07/09/2019] [Accepted: 07/22/2019] [Indexed: 01/17/2023]
Abstract
Phospholipids are the main component of membranes and are responsible for cell integrity. Alkylphospholipid analogues (APs) were first designed as antitumoral agents and were later tested against different cell types. Trypanosoma cruzi, the Chagas disease etiological agent, is sensitive to APs (edelfosine, miltefosine and ilmofosine) in vitro. We investigated the effect of synthetic ring substituted AP against epimastigotes, amastigotes and trypomastigotes. TCAN26, could inhibit the in vitro growth of epimastigotes and amastigotes with the 50% inhibitory concentrations (IC50) in the nanomolar range. Trypomastigotes lysis was also induced with 24-h treatment and a LC50 of 2.3 μM. Ultrastructural analysis by electron microscopy demonstrated that TCAN26 mainly affected the parasite's membranes leading to mitochondrial and Golgi cisternae swelling, membrane blebs, and autophagic figures in the different parasite developmental stages. While the Golgi of the parasites was significantly affected, the Golgi complex of the host cells remained normal suggesting a specific mechanism of action. In summary, our results suggest that TCAN 26 is a potent and selective inhibitor of T. cruzi growth probably due to disturbances of phospholipid biosynthesis.
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Affiliation(s)
- Emile Barrias
- Laboratório de Microscopia Aplicada a Ciencias da Vida, Diretoria de Metrologia Aplicada a Ciências da Vida, Instituto Nacional de Metrologia, Qualidade e Tecnologia -INMETRO, Xerém, Avenida Nossa Senhora das Graças, 50/ 27, 25250- 020, Duque de Caxias, Rio de Janeiro, Brazil
| | - Lissa Catherine Reignault
- Instituto Nacional de Ciência e Tecnologia em Biologia Estrutural e Bioimagens, Bloco K, 21944-970, Rio de Janeiro, Brazil; Laboratório de Ultraestrutura Celular Hertha Meyer, Instituto de Biofísica Carlos Chagas Filho, CCS, UFRJ, Av. Carlos Chagas 373, CCS, Ilha do Fundão, Rio de Janeiro, 21941-902, Brazil
| | - Theodora Calogeropoulou
- Institute of Biology, Medicinal Chemistry and Biotechnology, National Hellenic Research Foundation, 48 Vassileos Constantinou Avenue, 11635, Athens, Greece
| | - Wanderley de Souza
- Instituto Nacional de Ciência e Tecnologia em Biologia Estrutural e Bioimagens, Bloco K, 21944-970, Rio de Janeiro, Brazil; Laboratório de Ultraestrutura Celular Hertha Meyer, Instituto de Biofísica Carlos Chagas Filho, CCS, UFRJ, Av. Carlos Chagas 373, CCS, Ilha do Fundão, Rio de Janeiro, 21941-902, Brazil.
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Anticancer mechanisms and clinical application of alkylphospholipids. Biochim Biophys Acta Mol Cell Biol Lipids 2012; 1831:663-74. [PMID: 23137567 DOI: 10.1016/j.bbalip.2012.10.008] [Citation(s) in RCA: 105] [Impact Index Per Article: 8.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/08/2012] [Revised: 10/28/2012] [Accepted: 10/29/2012] [Indexed: 11/20/2022]
Abstract
Synthetic alkylphospholipids (ALPs), such as edelfosine, miltefosine, perifosine, erucylphosphocholine and erufosine, represent a relatively new class of structurally related antitumor agents that act on cell membranes rather than on DNA. They selectively target proliferating (tumor) cells, inducing growth arrest and apoptosis, and are potent sensitizers of conventional chemo- and radiotherapy. ALPs easily insert in the outer leaflet of the plasma membrane and cross the membrane via an ATP-dependent CDC50a-containing 'flippase' complex (in carcinoma cells), or are internalized by lipid raft-dependent endocytosis (in lymphoma/leukemic cells). ALPs resist catabolic degradation, therefore accumulate in the cell and interfere with lipid-dependent survival signaling pathways, notably PI3K-Akt and Raf-Erk1/2, and de novo phospholipid biosynthesis. At the same time, stress pathways (e.g. stress-activated protein kinase/JNK) are activated to promote apoptosis. In many preclinical and clinical studies, perifosine was the most effective ALP, mainly because it inhibits Akt activity potently and consistently, also in vivo. This property is successfully exploited clinically in highly malignant tumors, such as multiple myeloma and neuroblastoma, in which a tyrosine kinase receptor/Akt pathway is amplified. In such cases, perifosine therapy is most effective in combination with conventional anticancer regimens or with rapamycin-type mTOR inhibitors, and may overcome resistance to these agents. This article is part of a Special Issue entitled Phospholipids and Phospholipid Metabolism.
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de Freitas-Junior PRG, Catta-Preta CMC, Andrade IDS, Cavalcanti DP, de Souza W, Einicker-Lamas M, Motta MCM. Effects of miltefosine on the proliferation, ultrastructure, and phospholipid composition of Angomonas deanei, a trypanosomatid protozoan that harbors a symbiotic bacterium. FEMS Microbiol Lett 2012; 333:129-37. [PMID: 22651853 DOI: 10.1111/j.1574-6968.2012.02607.x] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/27/2012] [Revised: 05/22/2012] [Accepted: 05/22/2012] [Indexed: 11/28/2022] Open
Abstract
Some trypanosomatids, such as Angomonas deanei formerly named as Crithidia deanei, present an obligatory intracellular bacterium, which maintains a mutualistic relationship with the host. Phosphatidylcholine (PC) is the major phospholipid in eukaryotes and an essential component of cell membranes playing structural, biochemical, and physiological roles. However, in prokaryotes, PC is present only in those species closely associated with eukaryotes, either in symbiotic or pathogenic interactions. In trypanosomatids, the endosymbiont envelope is composed by a reduced cell wall and by two membrane units that lack sterols and present cardiolipin (CL) and PC as the major phospholipids. In this study, we tested the effects of miltefosine in A. deanei proliferation, as well as, on the ultrastrucuture and phospholipid composition considering that this drug inhibits the CTP-phosphocholine cytidyltransferase (CCT), a key enzyme in the PC biosynthesis. Besides the low effect of miltefosine in cellular proliferation, treated protozoa presented ultrastructural alterations such as plasma membrane shedding and blebbing, mitochondrial swelling, and convolutions of the endosymbiont envelope. The use of (32) Pi as a tracer revealed that the production of PC, CL, and phosphatidylethanolamine decreased while phosphatidylinositol production remained stable. Mitochondrion and symbiont fractions obtained from protozoa treated with miltefosine also presented a decrease in phospholipid production, reinforcing the idea that an intensive metabolic exchange occurs between the host trypanosomatid and structures of symbiotic origin.
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Affiliation(s)
- Paulo R G de Freitas-Junior
- Laboratório de Ultraestrutura Celular Hertha Meyer, Instituto de Biofísica Carlos Chagas Filho, Universidade Federal do Rio de Janeiro, Rio de Janeiro, RJ, Brazil
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González-Bulnes P, Bobenchik AM, Augagneur Y, Cerdan R, Vial HJ, Llebaria A, Ben Mamoun C. PG12, a phospholipid analog with potent antimalarial activity, inhibits Plasmodium falciparum CTP:phosphocholine cytidylyltransferase activity. J Biol Chem 2011; 286:28940-28947. [PMID: 21705805 DOI: 10.1074/jbc.m111.268946] [Citation(s) in RCA: 17] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022] Open
Abstract
In the human malaria parasite Plasmodium falciparum, the synthesis of the major and essential membrane phospholipid, phosphatidylcholine, occurs via the CDP-choline and the serine decarboxylase phosphoethanolamine methylation (SDPM) pathways, which are fueled by host choline, serine, and fatty acids. Both pathways share the final two steps catalyzed by two essential enzymes, P. falciparum CTP:phosphocholine cytidylyltransferase (PfCCT) and choline-phosphate transferase (PfCEPT). We identified a novel class of phospholipid mimetics, which inhibit the growth of P. falciparum as well as Leishmania and Trypanosoma species. Metabolic analyses showed that one of these compounds, PG12, specifically blocks phosphatidylcholine biosynthesis from both the CDP-choline and SDPM pathways via inhibition of PfCCT. In vitro studies using recombinant PfCCT showed a dose-dependent inhibition of the enzyme by PG12. The potent antimalarial of this compound, its low cytotoxicity profile, and its established mode of action make it an excellent lead to advance for further drug development and efficacy in vivo.
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Affiliation(s)
- Patricia González-Bulnes
- Research Unit on BioActive Molecules (RUBAM), Departament de Química Biomèdica, Instituto de Química Avanzada de Cataluña IQAC, CSIC, Jordi Girona 18-26, 08034 Barcelona, Spain
| | - April M Bobenchik
- Department of Internal Medicine, Yale University School of Medicine, New Haven, Connecticut 06520, and
| | - Yoann Augagneur
- Department of Internal Medicine, Yale University School of Medicine, New Haven, Connecticut 06520, and
| | - Rachel Cerdan
- Dynamique des Interactions Membranaires Normales et Pathologiques, CNRS UMR 5235, Universite Montpellier II, 34095 Montpellier, France
| | - Henri J Vial
- Dynamique des Interactions Membranaires Normales et Pathologiques, CNRS UMR 5235, Universite Montpellier II, 34095 Montpellier, France
| | - Amadeu Llebaria
- Research Unit on BioActive Molecules (RUBAM), Departament de Química Biomèdica, Instituto de Química Avanzada de Cataluña IQAC, CSIC, Jordi Girona 18-26, 08034 Barcelona, Spain,.
| | - Choukri Ben Mamoun
- Department of Internal Medicine, Yale University School of Medicine, New Haven, Connecticut 06520, and.
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Different cell death pathways induced by drugs in Trypanosoma cruzi: An ultrastructural study. Micron 2009; 40:157-68. [DOI: 10.1016/j.micron.2008.08.003] [Citation(s) in RCA: 115] [Impact Index Per Article: 7.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/26/2008] [Accepted: 08/26/2008] [Indexed: 11/23/2022]
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Dymond M, Attard G, Postle AD. Testing the hypothesis that amphiphilic antineoplastic lipid analogues act through reduction of membrane curvature elastic stress. J R Soc Interface 2008; 5:1371-86. [PMID: 18426775 DOI: 10.1098/rsif.2008.0041] [Citation(s) in RCA: 21] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/12/2022] Open
Abstract
The alkyllysophospholipid (ALP) analogues Mitelfosine and Edelfosine are anticancer drugs whose mode of action is still the subject of debate. It is agreed that the primary interaction of these compounds is with cellular membranes. Furthermore, the membrane-associated protein CTP: phosphocholine cytidylyltransferase (CCT) has been proposed as the critical target. We present the evaluation of our hypothesis that ALP analogues disrupt membrane curvature elastic stress and inhibit membrane-associated protein activity (e.g. CCT), ultimately resulting in apoptosis. This hypothesis was tested by evaluating structure-activity relationships of ALPs from the literature. In addition we characterized the lipid typology, cytotoxicity and critical micelle concentration of novel ALP analogues that we synthesized. Overall we find the literature data and our experimental data provide excellent support for the hypothesis, which predicts that the most potent ALP analogues will be type I lipids.
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Affiliation(s)
- Marcus Dymond
- School of Chemistry, University of Southampton, Highfield, UK
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Rakotomanga M, Blanc S, Gaudin K, Chaminade P, Loiseau PM. Miltefosine affects lipid metabolism in Leishmania donovani promastigotes. Antimicrob Agents Chemother 2007; 51:1425-30. [PMID: 17242145 PMCID: PMC1855451 DOI: 10.1128/aac.01123-06] [Citation(s) in RCA: 114] [Impact Index Per Article: 6.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022] Open
Abstract
Miltefosine (hexadecylphosphocholine [HePC]) is the first orally active antileishmanial drug. Transient HePC treatment of Leishmania donovani promastigotes at 10 microM significantly reduced the phosphatidylcholine content and enhanced the phosphatidylethanolamine (PE) content in parasite membranes, suggesting a partial inactivation of PE-N-methyltransferase. Phospholipase D activity did not seem to be affected by HePC. In addition, the enhancement of the lysophosphatidylcholine content could be ascribed to phospholipase A2 activation. Moreover, transient HePC treatment had no effect on the fatty acid alkyl chain length or the fatty acid unsaturation rate. Concerning sterols, we found a strong reduction of the C24 alkylated sterol content, and the enhancement of the cholesterol content could be the result of the HePC condensation effect with sterols. Because some of the effects observed after transient HePC treatment were different from those previously observed in HePC-resistant parasites, it could be hypothesized that continuous in vitro drug pressure induces the mechanisms of regulation in Leishmania lipid metabolism.
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Affiliation(s)
- M Rakotomanga
- Chimiothérapie Antiparasitaire, UMR 8076 CNRS, Faculté de Pharmacie, Université Paris-Sud XI, F-92290 Châtenay-Malabry, France
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10
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Urbina JA. Mechanisms of action of lysophospholipid analogues against trypanosomatid parasites. Trans R Soc Trop Med Hyg 2006; 100 Suppl 1:S9-S16. [PMID: 16930650 DOI: 10.1016/j.trstmh.2006.03.010] [Citation(s) in RCA: 31] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/02/2005] [Revised: 02/18/2006] [Accepted: 03/09/2006] [Indexed: 10/24/2022] Open
Abstract
Lysophospholipid analogues (LPAs) comprise a class of metabolically stable compounds that have been developed as anticancer agents for over two decades, but which have also potent and selective antiparasitic activity, particularly against trypanosomatid parasites such as Leishmania and Trypanosoma cruzi, both in vitro and in vivo. The in vivo activities of LPAs result from direct effects on their target cells and are not dependent on a functional immune system. Because of their chemical nature, LPAs have a potential for interaction with a variety of subcellular structures and biochemical pathways. However, in mammalian cells LPA-induced growth inhibition and programmed cell death is usually associated with a blockade of phosphatidylcholine (PC) biosynthesis at the level of CTP: phosphocholine citidyltransferase, probably through an increase of cellular ceramide levels due to depressed sphingomyelin synthesis. Although in trypanosomatid parasites much less information is available, inhibition of PC biosynthesis by LPA has also been documented but at the level of phosphatidylethanolamine N-methyl-transferase, as well as LPA-induced classical apoptotic phenomena. The higher activity of LPAs as inhibitors of PC biosynthesis in parasites than in mammalian cells, probably due to different biochemical pathways involved in the two types of cells, could explain their selective antiparasitic action in vivo.
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Affiliation(s)
- Julio A Urbina
- Laboratorio de Química Biológica, Centro de Biofísica y Bioquímica, Instituto Venezolano de Investigaciones Cientificas, Apartado 21827, Caracas 1020A, Venezuela.
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11
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Lira R, Contreras LM, Rita RM, Urbina JA. Mechanism of action of anti-proliferative lysophospholipid analogues against the protozoan parasite Trypanosoma cruzi: potentiation of in vitro activity by the sterol biosynthesis inhibitor ketoconazole. J Antimicrob Chemother 2001; 47:537-46. [PMID: 11328763 DOI: 10.1093/jac/47.5.537] [Citation(s) in RCA: 61] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/14/2022] Open
Abstract
We investigated the mechanism of action of metabolically stable lysophospholipid analogues (LPAs), with potent anti-tumour and anti-protozoal activity against Trypanosoma cruzi, the causative agent of Chagas' disease. Against the axenically grown epimastigote form of the parasite, the IC(50)s after 120 h for ET-18-OCH(3), miltefosine and ilmofosine were 3, 1 and 3 microM, respectively; at higher concentrations immediate lytic effects were observed. Eradication of the intracellular amastigote, grown inside Vero cells, was achieved at 0.1, 0.1 and 1 microM for ET-18-OCH(3), miltefosine and ilmofosine, respectively. Analysis of the lipid composition of epimastigotes exposed to LPAs at their IC(50) for 120 h showed that the ratio of phosphatidyl-choline (PC) to phosphatidylethanolamine (PE) changed from 1.5 in control cells to c. 0.67 in those treated with the analogues. A significant increase in the content of phosphatidylserine was also observed in treated cells. Intact epimastigotes efficiently incorporated radioactivity from L-[methyl-(14)C]methionine into PC, but not from [methyl-(14)C]choline. ET-18-OCH(3) inhibited the incorporation of L-[methyl-(14)C]methionine into PC with an IC(50) of 2 microM, suggesting that inhibition of the de novo synthesis through the Greenberg's pathway was a primary effect underlying the selective anti-parasitic activity of this compound. Antiproliferative synergism was observed as a consequence of combined treatment of epimastigotes with ET-18-OCH(3) and ketoconazole, a sterol biosynthesis inhibitor, probably due to the fact that a secondary effect of the latter is also a blockade of PC synthesis at the level of PE-PC-N-methyl-transferase.
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Affiliation(s)
- R Lira
- Laboratorio de Química Biológica, Centro de Biofísica y Bioquímica, Instituto Venezolano de Investigaciones Científicas, Apartado 21827, Caracas 1020A, Venezuela
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12
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Lykidis A, Jackowski S. Regulation of mammalian cell membrane biosynthesis. PROGRESS IN NUCLEIC ACID RESEARCH AND MOLECULAR BIOLOGY 2000; 65:361-93. [PMID: 11008493 DOI: 10.1016/s0079-6603(00)65010-9] [Citation(s) in RCA: 89] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 10/26/2022]
Abstract
This review explores current information on the interrelationship between phospholipid biochemistry and cell biology. Phosphatidylcholine is the most abundant phospholipid and it biosynthesis has been studied extensively. The choline cytidylyltransferase regulates phosphatidylcholine production, and recent advances in our understanding of the mechanisms that govern cytidylyltransferase include the discovery of multiple isoforms and a more complete understanding of the lipid regulation of enzyme activity. Similarities between phosphatidylcholine formation and the phosphatidylethanolamine and phosphatidylinositol biosynthetic pathways are discussed, together with current insight into control mechanisms. Membrane phospholipid doubling during cell cycle progression is a function of periodic biosynthesis and degradation. Membrane homeostasis is maintained by a phospholipase A-mediated degradation of excess phospholipid, whereas insufficient phosphatidylcholine triggers apoptosis in cells.
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Affiliation(s)
- A Lykidis
- Department of Biochemistry, St. Jude Children's Research Hospital, Memphis, Tennessee 38105, USA
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13
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Santa-Rita RM, Santos Barbosa H, Meirelles MN, de Castro SL. Effect of the alkyl-lysophospholipids on the proliferation and differentiation of Trypanosoma cruzi. Acta Trop 2000; 75:219-28. [PMID: 10708662 DOI: 10.1016/s0001-706x(00)00052-8] [Citation(s) in RCA: 55] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Abstract
Alkyl-lysophospholipids (ALPs), designed as potential immunomodulators, have been shown to be cytotoxic for a variety of tumour cells and are under clinical studies for cancer chemotherapy. ET-18-OCH(3), hexadecylphosphocholine and ilmofosine were assayed against the three forms of Trypanosoma cruzi. Incubation with bloodstream trypomastigotes resulted, under different experimental conditions, in higher activity of the compounds in comparison with crystal violet. The ED(50)/24 h values were 13.4+/-2.8 microM and 11. 7+/-0.6 microM for amastigotes and epimastigotes, respectively. ET-18-OCH(3) (0.3 and 0.6 microM) inhibited the differentiation of epimastigotes to trypomastigotes (Dm28C clone) in the range 40-57%. This drug (3.75-15 microM) also caused a time- and dose-dependent inhibition of the intracellular proliferation of amastigotes in heart muscle cells with ED(50) values of 14.3+/-4.2, 8.9+/-1.9 and 6. 8+/-0.4 microM, after 1, 2 and 3 days of treatment. Pre-treatment of the parasite with this drug inhibited its interiorization into the host cell. Interestingly, the intracellular differentiation of amastigotes to trypomastigotes was not hampered by the drug. The present results demonstrate the lytic effect of ALPs on the three forms of T. cruzi, as well as the inhibition of both the differentiation to the infective form and the proliferation of parasites interiorized in heart cells. Ultrastructural analysis of epimastigotes treated with the three ALPs showed extensive blebing of the flagellar membrane. As described in tumour cells, the membrane seems to be a primary target of the drugs.
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Affiliation(s)
- R M Santa-Rita
- Laboratório de Biologia Celular, DUBC, Instituto Oswaldo Cruz, Fundação Oswaldo Cruz, CP 926, 21045-900, Rio de Janeiro, Brazil
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Wieder T, Reutter W, Orfanos CE, Geilen CC. Mechanisms of action of phospholipid analogs as anticancer compounds. Prog Lipid Res 1999; 38:249-59. [PMID: 10664795 DOI: 10.1016/s0163-7827(99)00004-1] [Citation(s) in RCA: 42] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/26/2022]
Affiliation(s)
- T Wieder
- Department of Dermatology, University Medical Center Benjamin Franklin, Free University of Berlin, Berlin-Steglitz, Germany
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15
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Wieder T, Orfanos CE, Geilen CC. Induction of ceramide-mediated apoptosis by the anticancer phospholipid analog, hexadecylphosphocholine. J Biol Chem 1998; 273:11025-31. [PMID: 9556584 DOI: 10.1074/jbc.273.18.11025] [Citation(s) in RCA: 127] [Impact Index Per Article: 4.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022] Open
Abstract
The prototype of a new class of antiproliferative phospholipid analogs, hexadecylphosphocholine (HePC), has been shown to inhibit tumor growth and is currently used for the treatment of cutaneous metastases of mammary carcinomas. Although several cellular targets of HePC, e.g. protein kinase C and CTP:phosphocholine cytidylyltransferase, have been proposed, the mechanisms of HePC-induced anticancer activity are still unclear. Considering that the antiproliferative effect of HePC correlates with inhibition of phosphatidylcholine biosynthesis, which is tightly coupled to sphingomyelin biosynthesis, we tested the hypothesis that treatment of cells with the anticancer drug leads to increased cellular ceramide and subsequently to apoptotic cell death. In the present study, we showed that 25 micromol/liter HePC induced apoptosis. In further experiments, we demonstrated that HePC inhibited the incorporation of radiolabeled choline into phosphatidylcholine and at a later time point into sphingomyelin. This was confirmed by metabolic labeling of the lipid backbone using radiolabeled serine, and it was shown that HePC decreased the incorporation of serine into sphingomyelin by 35% and simultaneously increased the incorporation of serine into ceramide by 70%. Determination of the amount of ceramide revealed an increase of 53% in HePC-treated cells compared with controls. In accordance with the hypothesis that elevated ceramide levels may be the missing link between the metabolic effects of HePC and its proapoptotic properties, HePC-induced apoptosis was blocked by fumonisin B1, an inhibitor of ceramide synthesis. Furthermore, we found that membrane-permeable ceramides additively increased the apoptotic effect of HePC.
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Affiliation(s)
- T Wieder
- Department of Dermatology, University Medical Center Benjamin Franklin, The Free University of Berlin, 12200 Berlin, Germany
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16
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Arthur G, Bittman R. The inhibition of cell signaling pathways by antitumor ether lipids. BIOCHIMICA ET BIOPHYSICA ACTA 1998; 1390:85-102. [PMID: 9487143 DOI: 10.1016/s0005-2760(97)00163-x] [Citation(s) in RCA: 65] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 02/06/2023]
Affiliation(s)
- G Arthur
- Department of Biochemistry and Molecular Biology, University of Manitoba, Winnipeg, Manitoba R3E 0W3, Canada
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