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Carnero LCG, Dos Reis TF, Diehl C, de Castro PA, Pontes L, Pinzan CF, Goldman GH. Milteforan, a promising veterinary commercial product against feline sporotrichosis. BIORXIV : THE PREPRINT SERVER FOR BIOLOGY 2024:2024.02.14.580352. [PMID: 38405873 PMCID: PMC10888911 DOI: 10.1101/2024.02.14.580352] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 02/27/2024]
Abstract
Sporotrichosis, the cutaneous mycosis most commonly reported in Latin America, is caused by the Sporothrix clinical clade species, including Sporothrix brasiliensis and Sporothrix schenckii sensu stricto. In Brazil, S. brasiliensis represents a vital health threat to humans and domestic animals due to its zoonotic transmission. Itraconazole, terbinafine, and amphotericin B are the most used antifungals for treating sporotrichosis. However, many strains of S. brasiliensis and S. schenckii have shown resistance to these agents, highlighting the importance of finding new therapeutic options. Here, we demonstrate that milteforan, a commercial veterinary product against dog leishmaniasis whose active principle is miltefosine, is a possible therapeutic alternative for the treatment of sporotrichosis, as observed by its fungicidal activity in vitro against different strains of S. brasiliensis and S. schenckii, and by its antifungal activity when used to treat infected epithelial cells and macrophages. Our results suggest milteforan as a possible alternative to treat feline sporotrichosis.
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Affiliation(s)
- Laura C García Carnero
- Faculdade de Ciências Farmacêuticas de Ribeirão Preto, Universidade de São Paulo, Ribeirão Preto, Brazil
| | - Thaila F Dos Reis
- Faculdade de Ciências Farmacêuticas de Ribeirão Preto, Universidade de São Paulo, Ribeirão Preto, Brazil
| | - Camila Diehl
- Faculdade de Ciências Farmacêuticas de Ribeirão Preto, Universidade de São Paulo, Ribeirão Preto, Brazil
| | - Patricia Alves de Castro
- Faculdade de Ciências Farmacêuticas de Ribeirão Preto, Universidade de São Paulo, Ribeirão Preto, Brazil
| | - Lais Pontes
- Faculdade de Ciências Farmacêuticas de Ribeirão Preto, Universidade de São Paulo, Ribeirão Preto, Brazil
| | - Camila Figueiredo Pinzan
- Faculdade de Ciências Farmacêuticas de Ribeirão Preto, Universidade de São Paulo, Ribeirão Preto, Brazil
| | - Gustavo H Goldman
- Faculdade de Ciências Farmacêuticas de Ribeirão Preto, Universidade de São Paulo, Ribeirão Preto, Brazil
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Criscuolo E, De Sciscio ML, De Cristofaro A, Nicoara C, Maccarrone M, Fezza F. Computational and Experimental Drug Repurposing of FDA-Approved Compounds Targeting the Cannabinoid Receptor CB1. Pharmaceuticals (Basel) 2023; 16:1678. [PMID: 38139805 PMCID: PMC10747202 DOI: 10.3390/ph16121678] [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: 10/31/2023] [Revised: 11/25/2023] [Accepted: 11/30/2023] [Indexed: 12/24/2023] Open
Abstract
The cannabinoid receptor 1 (CB1R) plays a pivotal role in regulating various physiopathological processes, thus positioning itself as a promising and sought-after therapeutic target. However, the search for specific and effective CB1R ligands has been challenging, prompting the exploration of drug repurposing (DR) strategies. In this study, we present an innovative DR approach that combines computational screening and experimental validation to identify potential Food and Drug Administration (FDA)-approved compounds that can interact with the CB1R. Initially, a large-scale virtual screening was conducted using molecular docking simulations, where a library of FDA-approved drugs was screened against the CB1R's three-dimensional structures. This in silico analysis allowed us to prioritize compounds based on their binding affinity through two different filters. Subsequently, the shortlisted compounds were subjected to in vitro assays using cellular and biochemical models to validate their interaction with the CB1R and determine their functional impact. Our results reveal FDA-approved compounds that exhibit promising interactions with the CB1R. These findings open up exciting opportunities for DR in various disorders where CB1R signaling is implicated. In conclusion, our integrated computational and experimental approach demonstrates the feasibility of DR for discovering CB1R modulators from existing FDA-approved compounds. By leveraging the wealth of existing pharmacological data, this strategy accelerates the identification of potential therapeutics while reducing development costs and timelines. The findings from this study hold the potential to advance novel treatments for a range of CB1R -associated diseases, presenting a significant step forward in drug discovery research.
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Affiliation(s)
- Emanuele Criscuolo
- Department of Experimental Medicine, Tor Vergata University of Rome, Via Montpellier 1, 00121 Rome, Italy; (E.C.); (C.N.)
| | - Maria Laura De Sciscio
- Department of Medicine, Campus Bio-Medico University of Rome, Via Alvaro del Portillo 21, 00128 Rome, Italy; (M.L.D.S.); (A.D.C.)
| | - Angela De Cristofaro
- Department of Medicine, Campus Bio-Medico University of Rome, Via Alvaro del Portillo 21, 00128 Rome, Italy; (M.L.D.S.); (A.D.C.)
| | - Catalin Nicoara
- Department of Experimental Medicine, Tor Vergata University of Rome, Via Montpellier 1, 00121 Rome, Italy; (E.C.); (C.N.)
| | - Mauro Maccarrone
- Department of Biotechnological and Applied Clinical Sciences, University of L’Aquila, Via Vetoio, Coppito, 67100 L’Aquila, Italy
- European Center for Brain Research/Santa Lucia Foundation IRCCS, Via Del Fosso di Fiorano 64, 00143 Rome, Italy
| | - Filomena Fezza
- Department of Experimental Medicine, Tor Vergata University of Rome, Via Montpellier 1, 00121 Rome, Italy; (E.C.); (C.N.)
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Krause BM, Bauer B, Neudörfl JM, Wieder T, Schmalz HG. ItaCORMs: conjugation with a CO-releasing unit greatly enhances the anti-inflammatory activity of itaconates. RSC Med Chem 2021; 12:2053-2059. [PMID: 35024614 PMCID: PMC8672850 DOI: 10.1039/d1md00163a] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/08/2021] [Accepted: 10/11/2021] [Indexed: 12/22/2022] Open
Abstract
Endogenous itaconate as well as the gasotransmitter CO have recently been described as powerful anti-inflammatory and immunomodulating agents. However, each of the two agents comes along with a major drawback: Whereas itaconates only exert beneficial effects at high concentrations above 100 μM, the uncontrolled application of CO has strong toxic effects. To solve these problems, we designed hybrid prodrugs, i.e. itaconates that are conjugated with an esterase-triggered CO-releasing acyloxycyclohexadiene-Fe(CO)3 unit (ItaCORMs). Here, we describe the synthesis of different ItaCORMs and demonstrate their anti-inflammatory potency in cellular assays of primary murine immune cells in the low μmolar range (<10 μM). Thus, ItaCORMs represent a promising new class of hybrid compounds with high clinical potential as anti-inflammatory agents.
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Affiliation(s)
- Bernhard M Krause
- University of Cologne, Department of Chemistry Greinstr. 4 5939 Köln Germany
| | - Britta Bauer
- University Medical Center Tübingen, Department of Dermatology Liebermeisterstr. 25 72076 Tübingen Germany
| | | | - Thomas Wieder
- University Medical Center Tübingen, Department of Dermatology Liebermeisterstr. 25 72076 Tübingen Germany.,Physiologisches Institut, Abteilung für Vegetative und Klinische Physiologie, Eberhard-Karls-Universität Tübingen Wilhelmstr. 56 72074 Tübingen Germany
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Hopff SM, Wang Q, Frias C, Ahrweiler M, Wilke N, Wilke N, Berkessel A, Prokop A. A metal-free salalen ligand with anti-tumor and synergistic activity in resistant leukemia and solid tumor cells via mitochondrial pathway. J Cancer Res Clin Oncol 2021; 147:2591-2607. [PMID: 34213662 PMCID: PMC8310854 DOI: 10.1007/s00432-021-03679-3] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/03/2020] [Accepted: 05/27/2021] [Indexed: 12/15/2022]
Abstract
PURPOSE Since the discovery of the well-known cis-platin, transition metal complexes are highly recognized as cytostatic agents. However, toxic side effects of the metal ions present in the complexes may pose significant problems for their future development. Therefore, we investigated the metal-free salalen ligand WQF 044. METHODS DNA fragmentations in leukemia (Nalm6) and solid tumor cells (BJAB, MelHO, MCF-7, RM82) proved the apoptotic effects of WQF 044, its overcoming of resistances and the cellular pathways that are affected by the substance. The apoptotic mechanisms finding were supported by western blot analysis, measurement of the mitochondrial membrane potential and polymerase chain reactions. RESULTS A complex intervention in the mitochondrial pathway of apoptosis with a Bcl-2 and caspase dependence was observed. Additionally, a wide range of tumors were affected by the ligand in a low micromolar range in-vitro. The compound overcame multidrug resistances in P-gp over-expressed acute lymphoblastic leukemia and CD95-downregulated Ewing's sarcoma cells. Quite remarkable synergistic effects with vincristine were observed in Burkitt-like lymphoma cells. CONCLUSION The investigation of a metal-free salalen ligand as a potential anti-cancer drug revealed in promising results for a future clinical use.
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Affiliation(s)
- Sina M Hopff
- Department of Pediatric Hematology/Oncology, Municipal Clinics of Cologne, Children's Hospital of the City Cologne, Amsterdamer Straße 59, 50735, Cologne, Germany.
| | - Qifang Wang
- Department of Chemistry, University of Cologne, Greinstraße 4, 50939, Cologne, Germany
| | - Corazon Frias
- Department of Pediatric Hematology/Oncology, Municipal Clinics of Cologne, Children's Hospital of the City Cologne, Amsterdamer Straße 59, 50735, Cologne, Germany
| | - Marie Ahrweiler
- Department of Pediatric Hematology/Oncology, Municipal Clinics of Cologne, Children's Hospital of the City Cologne, Amsterdamer Straße 59, 50735, Cologne, Germany
| | - Nicola Wilke
- Department of Pediatric Hematology/Oncology, Municipal Clinics of Cologne, Children's Hospital of the City Cologne, Amsterdamer Straße 59, 50735, Cologne, Germany
| | - Nathalie Wilke
- Department of Pediatric Hematology/Oncology, Municipal Clinics of Cologne, Children's Hospital of the City Cologne, Amsterdamer Straße 59, 50735, Cologne, Germany
| | - Albrecht Berkessel
- Department of Chemistry, University of Cologne, Greinstraße 4, 50939, Cologne, Germany
| | - Aram Prokop
- Department of Pediatric Hematology/Oncology, Municipal Clinics of Cologne, Children's Hospital of the City Cologne, Amsterdamer Straße 59, 50735, Cologne, Germany
- Department of Pediatric Hematology/Oncology, Helios Clinic Schwerin, Wismarsche Straße 393-397, 19055, Schwerin, Germany
- Medical School Hamburg (MSH), University of Applied Sciences and Medical University, Am Kaiserkai 1, 20457, Hamburg, Germany
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Bioactive Ether Lipids: Primordial Modulators of Cellular Signaling. Metabolites 2021; 11:metabo11010041. [PMID: 33430006 PMCID: PMC7827237 DOI: 10.3390/metabo11010041] [Citation(s) in RCA: 20] [Impact Index Per Article: 6.7] [Reference Citation Analysis] [Abstract] [Key Words] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/30/2020] [Revised: 01/01/2021] [Accepted: 01/03/2021] [Indexed: 12/14/2022] Open
Abstract
The primacy of lipids as essential components of cellular membranes is conserved across taxonomic domains. In addition to this crucial role as a semi-permeable barrier, lipids are also increasingly recognized as important signaling molecules with diverse functional mechanisms ranging from cell surface receptor binding to the intracellular regulation of enzymatic cascades. In this review, we focus on ether lipids, an ancient family of lipids having ether-linked structures that chemically differ from their more prevalent acyl relatives. In particular, we examine ether lipid biosynthesis in the peroxisome of mammalian cells, the roles of selected glycerolipids and glycerophospholipids in signal transduction in both prokaryotes and eukaryotes, and finally, the potential therapeutic contributions of synthetic ether lipids to the treatment of cancer.
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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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Tzoneva R, Stoyanova T, Petrich A, Popova D, Uzunova V, Momchilova A, Chiantia S. Effect of Erufosine on Membrane Lipid Order in Breast Cancer Cell Models. Biomolecules 2020; 10:E802. [PMID: 32455962 PMCID: PMC7277205 DOI: 10.3390/biom10050802] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/02/2020] [Revised: 05/15/2020] [Accepted: 05/19/2020] [Indexed: 12/11/2022] Open
Abstract
Alkylphospholipids are a novel class of antineoplastic drugs showing remarkable therapeutic potential. Among them, erufosine (EPC3) is a promising drug for the treatment of several types of tumors. While EPC3 is supposed to exert its function by interacting with lipid membranes, the exact molecular mechanisms involved are not known yet. In this work, we applied a combination of several fluorescence microscopy and analytical chemistry approaches (i.e., scanning fluorescence correlation spectroscopy, line-scan fluorescence correlation spectroscopy, generalized polarization imaging, as well as thin layer and gas chromatography) to quantify the effect of EPC3 in biophysical models of the plasma membrane, as well as in cancer cell lines. Our results indicate that EPC3 affects lipid-lipid interactions in cellular membranes by decreasing lipid packing and increasing membrane disorder and fluidity. As a consequence of these alterations in the lateral organization of lipid bilayers, the diffusive dynamics of membrane proteins are also significantly increased. Taken together, these findings suggest that the mechanism of action of EPC3 could be linked to its effects on fundamental biophysical properties of lipid membranes, as well as on lipid metabolism in cancer cells.
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Affiliation(s)
- Rumiana Tzoneva
- Bulgarian Academy of Sciences, Institute of Biophysics and Biomedical Engineering, 1113 Sofia, Bulgaria; (R.T.); (T.S.); (D.P.); (V.U.); (A.M.)
| | - Tihomira Stoyanova
- Bulgarian Academy of Sciences, Institute of Biophysics and Biomedical Engineering, 1113 Sofia, Bulgaria; (R.T.); (T.S.); (D.P.); (V.U.); (A.M.)
| | - Annett Petrich
- Institute of Biochemistry and Biology, University of Potsdam, Karl-Liebknecht-Street 24-25, 14476 Potsdam, Germany;
| | - Desislava Popova
- Bulgarian Academy of Sciences, Institute of Biophysics and Biomedical Engineering, 1113 Sofia, Bulgaria; (R.T.); (T.S.); (D.P.); (V.U.); (A.M.)
| | - Veselina Uzunova
- Bulgarian Academy of Sciences, Institute of Biophysics and Biomedical Engineering, 1113 Sofia, Bulgaria; (R.T.); (T.S.); (D.P.); (V.U.); (A.M.)
| | - Albena Momchilova
- Bulgarian Academy of Sciences, Institute of Biophysics and Biomedical Engineering, 1113 Sofia, Bulgaria; (R.T.); (T.S.); (D.P.); (V.U.); (A.M.)
| | - Salvatore Chiantia
- Institute of Biochemistry and Biology, University of Potsdam, Karl-Liebknecht-Street 24-25, 14476 Potsdam, Germany;
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The effect of edelfosine on GRA1 and MIC3 expressions in acute toxoplasmosis. Parasitol Res 2020; 119:1371-1380. [PMID: 31970471 DOI: 10.1007/s00436-020-06601-x] [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: 11/12/2019] [Accepted: 01/06/2020] [Indexed: 10/25/2022]
Abstract
Phosphoinositide-dependent phospholipase-C (PI-PLC) triggers the calcium signaling pathway which plays an important role in dense granule and microneme secretion and pathogenesis of Toxoplasma gondii (T. gondii). There are limited data about the effects of phospholipid analogues against T. gondii. The current study assessed the effect of edelfosine, as a phospholipid analogue, on GRA1 and MIC3 expressions using in vitro and in vivo models of acute toxoplasmosis. Infected Vero cells were treated by edelfosine in two subgroups: 24 h following the cell infection and treatment at the same time of cell infection. Animal study was performed on forty mice in four groups including non-infected, infected untreated, infected edelfosine-treated, and infected pyrimethamine-treated. Gene and protein expression analyses were done using quantitative real-time PCR and western blot, respectively. Edelfosine significantly reduced the GRA1 (P < 0.01) and MIC3 (P < 0.01) mRNA and protein expressions in 24 h following the cell infection and at the same time of cell infection groups. In vivo study showed that the edelfosine significantly reduced the GRA1 expression in eye, and MIC3 expression in brain and liver. Moreover, the edelfosine-treated infected mice had significant higher survival rate compared with uninfected mice. The reducing effect of edelfosine on GRA1 and MIC3 mRNA and protein levels 24 h following the cell infection was more than treatment at the same time of cell infection group. Moreover, the effect of edelfosine on GRA1 and MIC3 expression in animal tissues was variable. These data showed that the edelfosine may decrease the T. gondii excretory/secretory antigens through inhibition of PI-PLC.
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Braga SS. Multi-target drugs active against leishmaniasis: A paradigm of drug repurposing. Eur J Med Chem 2019; 183:111660. [PMID: 31514064 DOI: 10.1016/j.ejmech.2019.111660] [Citation(s) in RCA: 41] [Impact Index Per Article: 8.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/29/2019] [Revised: 08/27/2019] [Accepted: 08/28/2019] [Indexed: 11/17/2022]
Abstract
This mini-review focuses on leishmanicidal drugs that were sourced from small molecules previously approved for other diseases. The mechanisms of action of these molecules are herein explored, to probe the origins of their inter-species growth inhibitory activities. It is shown how the transversal action of the azoles - fluconazole, posaconazole and itraconazole - in both fungi and Leishmania is due to the occurrence of the same target, lanosterol 14-α-demethylase, in these two groups of species. In turn, the drugs miltefosine and amphotericin B are presented as truly multi-target agents, acting on small molecules, proteins, genes and even organelles. Steps towards future leishmanicidal drug candidates based on the multi-target strategy and on drug repurposing are also briefly presented.
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Affiliation(s)
- Susana Santos Braga
- QOPNA & LAQV/REQUIMTE, Department of Chemistry, University of Aveiro, 3810-193, Aveiro, Portugal.
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Synthesis and biological evaluation of new long-chain squaramides as anti-chagasic agents in the BALB/c mouse model. Bioorg Med Chem 2019; 27:865-879. [PMID: 30728107 DOI: 10.1016/j.bmc.2019.01.033] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/03/2018] [Revised: 01/25/2019] [Accepted: 01/28/2019] [Indexed: 12/28/2022]
Abstract
Chagas Disease is caused by infection with the insect-transmitted protozoan Trypanosoma cruzi and affects more than 10 million people. It is a paradigmatic example of a chronic disease without an effective treatment in Latin America where the current therapies, based on Benznidazole and Nifurtimox, are characterised by limited efficacy, toxic side-effects and frequent failures in the treatment. We present a series of new long-chain squaramides, identified based on their 1H and 13C NMR spectra, and their trypanocidal activity and cytotoxicity were tested in vitro through the determination of IC50 values. Compounds 4 and 7 were more active and less toxic than the reference drug Benznidazole, and these results were the basis of promoting in vivo assays, where parasitaemia levels, assignment of cure, reactivation of parasitaemia and others parameters were determined in mice treated in both the acute and chronic phases. Finally, the mechanisms of action were elucidated at metabolic and mitochondrial levels and superoxide dismutase inhibition. The experiments allowed us to select compound 7 as a promising candidate for treating Chagas Disease, where the activity, stability and low cost make long-chain squaramides appropriate molecules for the development of an affordable anti-chagasic agent versus current treatments.
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Phokrai P, Poolsri W, Suwankulanan S, Phakdeeto N, Kaewkong W, Pekthong D, Richert L, Srisawang P. Suppressed de novo lipogenesis by plasma membrane citrate transporter inhibitor promotes apoptosis in HepG2 cells. FEBS Open Bio 2018; 8:986-1000. [PMID: 29928578 PMCID: PMC5986055 DOI: 10.1002/2211-5463.12435] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/17/2017] [Revised: 04/03/2018] [Accepted: 04/18/2018] [Indexed: 01/02/2023] Open
Abstract
Suppression of the expression or activities of enzymes that are involved in the synthesis of de novo lipogenesis (DNL) in cancer cells triggers cell death via apoptosis. The plasma membrane citrate transporter (PMCT) is the initial step that translocates citrate from blood circulation into the cytoplasm for de novo long-chain fatty acids synthesis. This study investigated the antitumor effect of the PMCT inhibitor (PMCTi) in inducing apoptosis by inhibiting the DNL pathway in HepG2 cells. The present findings showed that PMCTi reduced cell viability and enhanced apoptosis through decreased intracellular citrate levels, which consequently caused inhibition of fatty acid and triacylglycerol productions. Thus, as a result of the reduction in fatty acid synthesis, the activity of carnitine palmitoyl transferase-1 (CPT-1) was suppressed. Decreased CPT-1 activity also facilitated the disruption of mitochondrial membrane potential (ΔΨm) leading to stimulation of apoptosis. Surprisingly, primary human hepatocytes were not affected by PMCTi. Increased caspase-8 activity as a consequence of reduction in fatty acid synthesis was also found to cause disruption of ΔΨm. In addition, apoptosis induction by PMCTi was associated with an enhanced reactive oxygen species generation. Taken together, we suggest that inhibition of the DNL pathway following reduction in citrate levels is an important regulator of apoptosis in HepG2 cells via suppression of CPT-1 activity. Thus, targeting the DNL pathway mediating CPT-1 activity by PMCTi may be a selective potential anticancer therapy.
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Affiliation(s)
- Phornpun Phokrai
- Department of Medical TechnologyFaculty of Science and TechnologyBansomdejchaopraya Rajabhat UniversityBangkokThailand
| | - Wan‐angkan Poolsri
- Department of PhysiologyFaculty of Medical ScienceNaresuan UniversityPhitsanulokThailand
| | - Somrudee Suwankulanan
- Department of PhysiologyFaculty of Medical ScienceNaresuan UniversityPhitsanulokThailand
| | - Narinthorn Phakdeeto
- Department of PhysiologyFaculty of Medical ScienceNaresuan UniversityPhitsanulokThailand
| | - Worasak Kaewkong
- Department of BiochemistryFaculty of Medical ScienceNaresuan UniversityPhitsanulokThailand
| | - Dumrongsak Pekthong
- Department of Pharmacy PracticeFaculty of Pharmaceutical SciencesNaresuan UniversityPhitsanulokThailand
| | | | - Piyarat Srisawang
- Department of PhysiologyFaculty of Medical ScienceNaresuan UniversityPhitsanulokThailand
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Metal-free salan-type compound induces apoptosis and overcomes multidrug resistance in leukemic and lymphoma cells in vitro. J Cancer Res Clin Oncol 2018; 144:685-695. [PMID: 29374786 DOI: 10.1007/s00432-018-2592-x] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/27/2017] [Accepted: 01/19/2018] [Indexed: 12/12/2022]
Abstract
PURPOSE We report on our preclinical findings of a simple salicylic diamine compound (THG 1213) which has yielded exceptional results as a potential chemotherapeutic drug. THG 1213 is an easy to synthesize chiral and metal-free salan compound. METHODS THG 1213 was tested on several leukemia, lymphoma and solid tumor cell lines in vitro. The effects have been studied by LDH release essay, FACS flow cytometry, photometric cell count, immunoblotting, and NMR spectroscopy. RESULTS THG 1213 selectively inhibits proliferation and induces apoptosis in leukemia, lymphoma and solid tumor cell lines. Necrosis or effects on healthy leucocytes could not be detected. Apoptosis is induced via the intrinsic and extrinsic pathways. The salan THG 1213 overcomes multidrug resistance in tumor cells and acts synergistically with vincristine and daunorubicin. CONCLUSIONS THG 1213 displays remarkable antitumor properties. In particular, the lack of metallic components of THG 1213 could prove to be beneficial in future clinical trials, as metal-containing drugs are known to show severe side effects.
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Mechanism of Action of Miltefosine on Leishmania donovani Involves the Impairment of Acidocalcisome Function and the Activation of the Sphingosine-Dependent Plasma Membrane Ca 2+ Channel. Antimicrob Agents Chemother 2017; 62:AAC.01614-17. [PMID: 29061745 DOI: 10.1128/aac.01614-17] [Citation(s) in RCA: 56] [Impact Index Per Article: 8.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/04/2017] [Accepted: 10/12/2017] [Indexed: 11/20/2022] Open
Abstract
Leishmania donovani is the causing agent of visceral leishmaniasis, a common infection that affects millions of people from the most underdeveloped countries. Miltefosine is the only oral drug to treat infections caused by L. donovani Nevertheless, its mechanism of action is not well understood. While miltefosine inhibits the synthesis of phosphatidylcholine and also affects the parasite mitochondrion, inhibiting the cytochrome c oxidase, it is to be expected that this potent drug also produces its effect through other targets. In this context, it has been reported that the disruption of the intracellular Ca2+ homeostasis represents an important object for the action of drugs in trypanosomatids. Recently, we have described a plasma membrane Ca2+ channel in Leishmania mexicana, which is similar to the L-type voltage-gated Ca2+ channel (VGCC) present in humans. Remarkably, the parasite Ca2+ channel is activated by sphingosine, while the L-type VGCC is not affected by this sphingolipid. In the present work we demonstrated that, similarly to sphingosine, miltefosine is able to activate the plasma membrane Ca2+ channel from L. donovani Interestingly, nifedipine, the classical antagonist of the human channel, was not able to fully block the parasite plasma membrane Ca2+ channel, indicating that the mechanism of interaction is not identical to that of sphingosine. In this work we also show that miltefosine is able to strongly affect the acidocalcisomes from L. donovani, inducing the rapid alkalinization of these important organelles. In conclusion, we demonstrate two new mechanisms of action of miltefosine in L. donovani, both related to disruption of parasite Ca2+ homeostasis.
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Arachidonic acid: Physiological roles and potential health benefits - A review. J Adv Res 2017; 11:33-41. [PMID: 30034874 PMCID: PMC6052655 DOI: 10.1016/j.jare.2017.11.004] [Citation(s) in RCA: 321] [Impact Index Per Article: 45.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/26/2017] [Revised: 11/16/2017] [Accepted: 11/17/2017] [Indexed: 12/17/2022] Open
Abstract
It is time to shift the arachidonic acid (ARA) paradigm from a harm-generating molecule to its status of polyunsaturated fatty acid essential for normal health. ARA is an integral constituent of biological cell membrane, conferring it with fluidity and flexibility, so necessary for the function of all cells, especially in nervous system, skeletal muscle, and immune system. Arachidonic acid is obtained from food or by desaturation and chain elongation of the plant-rich essential fatty acid, linoleic acid. Free ARA modulates the function of ion channels, several receptors and enzymes, via activation as well as inhibition. That explains its fundamental role in the proper function of the brain and muscles and its protective potential against Schistosoma mansoni and S. haematobium infection and tumor initiation, development, and metastasis. Arachidonic acid in cell membranes undergoes reacylation/deacylation cycles, which keep the concentration of free ARA in cells at a very low level and limit ARA availability to oxidation. Metabolites derived from ARA oxidation do not initiate but contribute to inflammation and most importantly lead to the generation of mediators responsible for resolving inflammation and wound healing. Endocannabinoids are oxidation-independent ARA derivatives, critically important for brain reward signaling, motivational processes, emotion, stress responses, pain, and energy balance. Free ARA and metabolites promote and modulate type 2 immune responses, which are critically important in resistance to parasites and allergens insult, directly via action on eosinophils, basophils, and mast cells and indirectly by binding to specific receptors on innate lymphoid cells. In conclusion, the present review advocates the innumerable ARA roles and considerable importance for normal health.
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Wieder T, Brenner E, Braumüller H, Bischof O, Röcken M. Cytokine-induced senescence for cancer surveillance. Cancer Metastasis Rev 2017; 36:357-365. [DOI: 10.1007/s10555-017-9667-z] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 12/13/2022]
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Ríos-Marco P, Marco C, Gálvez X, Jiménez-López JM, Carrasco MP. Alkylphospholipids: An update on molecular mechanisms and clinical relevance. BIOCHIMICA ET BIOPHYSICA ACTA-BIOMEMBRANES 2017; 1859:1657-1667. [PMID: 28238819 DOI: 10.1016/j.bbamem.2017.02.016] [Citation(s) in RCA: 47] [Impact Index Per Article: 6.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/17/2016] [Revised: 02/20/2017] [Accepted: 02/21/2017] [Indexed: 11/16/2022]
Abstract
Alkylphospholipids (APLs) represent a new class of drugs which do not interact directly with DNA but act on the cell membrane where they accumulate and interfere with lipid metabolism and signalling pathways. This review summarizes the mode of action at the molecular level of these compounds. In this sense, a diversity of mechanisms has been suggested to explain the actions of clinically-relevant APLs, in particular, in cancer treatment. One consistently reported finding is that APLs reduce the biosynthesis of phosphatidylcholine (PC) by inhibiting the rate-limiting enzyme CTP:phosphocholine cytidylyltransferase (CT). APLs also alter intracellular cholesterol traffic and metabolism in human tumour-cell lines, leading to an accumulation of cholesterol inside the cell. An increase in cholesterol biosynthesis associated with a decrease in the synthesis of choline-containing phospholipids and cholesterol esterification leads to a change in the free-cholesterol:PC ratio in cells exposed to APLs. Akt phosphorylation status after APL exposure shows that this critical regulator for cell survival is modulated by changes in cholesterol levels induced in the plasma membrane by these lipid analogues. Furthermore, APLs produce cell ultrastructural alterations with an abundant autophagic vesicles and autolysosomes in treated cells, indicating an interference of autophagy process after APL exposure. Thus, antitumoural APLs interfere with the proliferation of tumour cells via a complex mechanism involving phospholipid and cholesterol metabolism, interfere with lipid-dependent survival-signalling pathways and autophagy. Although APLs also exert antiparasitic, antibacterial, and antifungal effects, in this review we provide a summary of the antileishmanial activity of these lipid analogues. This article is part of a Special Issue entitled: Membrane Lipid Therapy: Drugs Targeting Biomembranes edited by Pablo V. Escribá.
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Affiliation(s)
- Pablo Ríos-Marco
- Department of Biochemistry and Molecular Biology I, Faculty of Sciences, University of Granada, Av. Fuentenueva s/n, Granada 18001, Spain
| | - Carmen Marco
- Department of Biochemistry and Molecular Biology I, Faculty of Sciences, University of Granada, Av. Fuentenueva s/n, Granada 18001, Spain
| | - Xiomara Gálvez
- Department of Biochemistry and Molecular Biology I, Faculty of Sciences, University of Granada, Av. Fuentenueva s/n, Granada 18001, Spain
| | - José M Jiménez-López
- Department of Biochemistry and Molecular Biology I, Faculty of Sciences, University of Granada, Av. Fuentenueva s/n, Granada 18001, Spain.
| | - María P Carrasco
- Department of Biochemistry and Molecular Biology I, Faculty of Sciences, University of Granada, Av. Fuentenueva s/n, Granada 18001, Spain.
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Fang R, Zhu X, Zhu Y, Tong X, Li K, Bai H, Li X, Ben J, Zhang H, Yang Q, Chen Q. Miltefosine Suppresses Hepatic Steatosis by Activating AMPK Signal Pathway. PLoS One 2016; 11:e0163667. [PMID: 27681040 PMCID: PMC5040442 DOI: 10.1371/journal.pone.0163667] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/13/2016] [Accepted: 09/12/2016] [Indexed: 12/14/2022] Open
Abstract
BACKGROUND AND PURPOSE It has been accepted that AMPK (Adenosine monophosphate-activated protein kinase) activation exhibits many beneficial effects on glucolipid metabolism. Lysophosphatidylcholine (LPC) is an important lysophospholipid which can improve blood glucose levels in diabetic mice and attenuate inflammation by activating AMPK signal pathway in macrophages. Synthetic alkylphospholipids (ALPs), such as miltefosine, is used as an alternate of LPC for the clinical application. Here, we investigated whether miltefosine could have an impact on hepatic steatosis and related metabolic disorders. EXPERIMENTAL APPROACH Mice were fed with high fat diet (HFD) for 16 weeks to generate an obese model. Next, the obese mice were randomly divided into three groups: saline-treated and miltefosine-treated (2.5 or 5 mg/kg/d) groups. Miltefosine was intraperitoneally administrated into mice for additional 4 weeks plus HFD treatment. KEY RESULTS It was shown that miltefosine treatment could substantially improve glucose metabolism, prevented hepatic lipid accumulation, and inhibited liver inflammation in HFD-fed mice by activating AMPK signal pathway. In vitro, miltefosine stimulated AMPKα phosphorylation both in time and dose dependent manner and decreased lipid accumulation in liver cells. When a specific AMPK inhibitor compound C was used to treat mice, the antagonistic effects of miltefosine on HFD-induced mouse hyperlipidaemia and liver steatosis were abolished. Treatment with miltefosine also dramatically inhibited the HFD-induced liver inflammation in mice. CONCLUSIONS AND IMPLICATIONS Here we demonstrated that miltefosine might be a new activator of AMPK signal pathway in vivo and in vitro and be useful for treatment of hepatic steatosis and related metabolic disorders.
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Affiliation(s)
- Ru Fang
- Atherosclerosis Research Center, Key Laboratory of Cardiovascular Disease and Molecular Intervention, Nanjing Medical University, Nanjing 210029, People’s Republic of China
| | - Xudong Zhu
- Atherosclerosis Research Center, Key Laboratory of Cardiovascular Disease and Molecular Intervention, Nanjing Medical University, Nanjing 210029, People’s Republic of China
| | - Yaqin Zhu
- Atherosclerosis Research Center, Key Laboratory of Cardiovascular Disease and Molecular Intervention, Nanjing Medical University, Nanjing 210029, People’s Republic of China
| | - Xing Tong
- Atherosclerosis Research Center, Key Laboratory of Cardiovascular Disease and Molecular Intervention, Nanjing Medical University, Nanjing 210029, People’s Republic of China
| | - Kexue Li
- Atherosclerosis Research Center, Key Laboratory of Cardiovascular Disease and Molecular Intervention, Nanjing Medical University, Nanjing 210029, People’s Republic of China
| | - Hui Bai
- Atherosclerosis Research Center, Key Laboratory of Cardiovascular Disease and Molecular Intervention, Nanjing Medical University, Nanjing 210029, People’s Republic of China
| | - Xiaoyu Li
- Atherosclerosis Research Center, Key Laboratory of Cardiovascular Disease and Molecular Intervention, Nanjing Medical University, Nanjing 210029, People’s Republic of China
| | - Jingjing Ben
- Atherosclerosis Research Center, Key Laboratory of Cardiovascular Disease and Molecular Intervention, Nanjing Medical University, Nanjing 210029, People’s Republic of China
| | - Hanwen Zhang
- Atherosclerosis Research Center, Key Laboratory of Cardiovascular Disease and Molecular Intervention, Nanjing Medical University, Nanjing 210029, People’s Republic of China
| | - Qing Yang
- Atherosclerosis Research Center, Key Laboratory of Cardiovascular Disease and Molecular Intervention, Nanjing Medical University, Nanjing 210029, People’s Republic of China
| | - Qi Chen
- Atherosclerosis Research Center, Key Laboratory of Cardiovascular Disease and Molecular Intervention, Nanjing Medical University, Nanjing 210029, People’s Republic of China
- * E-mail:
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Ahlberg S, Meinke MC, Werner L, Epple M, Diendorf J, Blume-Peytavi U, Lademann J, Vogt A, Rancan F. Comparison of silver nanoparticles stored under air or argon with respect to the induction of intracellular free radicals and toxic effects toward keratinocytes. Eur J Pharm Biopharm 2014; 88:651-7. [DOI: 10.1016/j.ejpb.2014.07.012] [Citation(s) in RCA: 26] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/13/2014] [Revised: 07/15/2014] [Accepted: 07/21/2014] [Indexed: 10/24/2022]
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Bibis SS, Dahlstrom K, Zhu T, Zufferey R. Characterization of Leishmania major phosphatidylethanolamine methyltransferases LmjPEM1 and LmjPEM2 and their inhibition by choline analogs. Mol Biochem Parasitol 2014; 196:90-9. [PMID: 25176160 PMCID: PMC4252796 DOI: 10.1016/j.molbiopara.2014.08.005] [Citation(s) in RCA: 17] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/03/2014] [Revised: 08/21/2014] [Accepted: 08/24/2014] [Indexed: 11/19/2022]
Abstract
Phosphatidylcholine (PC) is the most abundant phospholipid in the membranes of the human parasite Leishmania. It is synthesized via two metabolic routes, the de novo pathway that starts with the uptake of choline, and the threefold methylation of phosphatidylethanolamine. Choline was shown to be dispensable for Leishmania; thus, the methylation pathway likely represents the primary route for PC production. Here, we have identified and characterized two phosphatidylethanolamine methyltransferases, LmjPEM1 and LmjPEM2. Both enzymes are expressed in promastigotes as well as in the vertebrate form amastigotes, suggesting that these methyltransferases are important for the development of the parasite throughout its life cycle. These enzymes are maximally expressed during the log phase of growth which correlates with the demand of PC synthesis during cell multiplication. Immunofluorescence studies combined with cell fractionation have shown that both methyltransferases are localized at the endoplasmic reticulum membrane. Heterologous expression in yeast has demonstrated that LmjPEM1 and LmjPEM2 complement the choline auxotrophy phenotype of a yeast double null mutant lacking phosphatidylethanolamine methyltransferase activity. LmjPEM1 catalyzes the first, and to a lesser extent, the second methylation reaction. In contrast, LmjPEM2 has the capacity to add the second and third methyl group onto phosphatidylethanolamine to yield (lyso)PC; it can also add the first methyl group, albeit with very low efficiency. Finally, we have demonstrated using inhibition studies with choline analogs that miltefosine and octadecyltrimethylammonium bromide are potent inhibitors of this metabolic pathway.
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Affiliation(s)
- Stergios S Bibis
- Department of Biological Sciences, St John's University, 8000 Utopia Parkway, Jamaica, NY 11439, USA
| | - Kelly Dahlstrom
- Department of Biochemistry, Kansas State University, Manhattan, KS 66506, USA
| | - Tongtong Zhu
- Department of Biological Sciences, St John's University, 8000 Utopia Parkway, Jamaica, NY 11439, USA
| | - Rachel Zufferey
- Department of Biological Sciences, St John's University, 8000 Utopia Parkway, Jamaica, NY 11439, USA; Department of Biochemistry, Kansas State University, Manhattan, KS 66506, USA.
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20
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Gontijo VS, Oliveira MÉ, Resende RJ, Fonseca AL, Nunes RR, Júnior MC, Taranto AG, Torres NMPO, Viana GHR, Silva LM, Alves RB, Varotti FP, Freitas RP. Long-chain alkyltriazoles as antitumor agents: synthesis, physicochemical properties, and biological and computational evaluation. Med Chem Res 2014. [DOI: 10.1007/s00044-014-1137-3] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/03/2023]
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Verhaar AP, Wildenberg ME, Peppelenbosch MP, Hommes DW, van den Brink GR. Repurposing miltefosine for the treatment of immune-mediated disease? J Pharmacol Exp Ther 2014; 350:189-95. [PMID: 24833702 DOI: 10.1124/jpet.113.212654] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/28/2022] Open
Abstract
Miltefosine is an ether lipid that was initially developed for cancer treatment in the early 1980s. Miltefosine largely failed development for oncology, although it was approved for the topical treatment of breast cancer metastasis. It was subsequently discovered that miltefosine is a highly effective treatment of visceral Leishmaniasis, a parasitic disease that affects millions worldwide and causes an estimated 30,000 fatalities each year. Oral treatment with miltefosine is generally well tolerated and has relatively few adverse effects. The exact mechanism of action of miltefosine treatment is still under investigation. Its close resemblance to phospholipids allows it to be quickly taken up by cell membranes and affect related processes, such as lipid metabolism and signaling through lipid rafts. These processes play an important role in the immune response and it comes as no surprise that miltefosine has been successfully tested for the treatment of a number of immune-mediated diseases in preclinical models of disease. Drug repurposing of miltefosine for immune-mediated diseases may provide an opportunity to expand the limited number of drugs that are currently available for therapeutic use.
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Affiliation(s)
- Auke P Verhaar
- Department of Gastroenterology and Hepatology, Tytgat Institute for Liver and Intestinal Research, Academic Medical Center, Amsterdam, The Netherlands (A.P.V., M.E.W., G.R.v.d.B.); Department of Gastroenterology and Hepatology, Leiden University Medical Center, Leiden, The Netherlands (A.P.V., D.W.H.); Department of Gastroenterology and Hepatology, Erasmus University Medical Center, Rotterdam, The Netherlands (M.P.P.); and Center for Inflammatory Bowel Diseases, University of California Los Angeles, Los Angeles, California (D.W.H.)
| | - Manon E Wildenberg
- Department of Gastroenterology and Hepatology, Tytgat Institute for Liver and Intestinal Research, Academic Medical Center, Amsterdam, The Netherlands (A.P.V., M.E.W., G.R.v.d.B.); Department of Gastroenterology and Hepatology, Leiden University Medical Center, Leiden, The Netherlands (A.P.V., D.W.H.); Department of Gastroenterology and Hepatology, Erasmus University Medical Center, Rotterdam, The Netherlands (M.P.P.); and Center for Inflammatory Bowel Diseases, University of California Los Angeles, Los Angeles, California (D.W.H.)
| | - Maikel P Peppelenbosch
- Department of Gastroenterology and Hepatology, Tytgat Institute for Liver and Intestinal Research, Academic Medical Center, Amsterdam, The Netherlands (A.P.V., M.E.W., G.R.v.d.B.); Department of Gastroenterology and Hepatology, Leiden University Medical Center, Leiden, The Netherlands (A.P.V., D.W.H.); Department of Gastroenterology and Hepatology, Erasmus University Medical Center, Rotterdam, The Netherlands (M.P.P.); and Center for Inflammatory Bowel Diseases, University of California Los Angeles, Los Angeles, California (D.W.H.)
| | - Daniel W Hommes
- Department of Gastroenterology and Hepatology, Tytgat Institute for Liver and Intestinal Research, Academic Medical Center, Amsterdam, The Netherlands (A.P.V., M.E.W., G.R.v.d.B.); Department of Gastroenterology and Hepatology, Leiden University Medical Center, Leiden, The Netherlands (A.P.V., D.W.H.); Department of Gastroenterology and Hepatology, Erasmus University Medical Center, Rotterdam, The Netherlands (M.P.P.); and Center for Inflammatory Bowel Diseases, University of California Los Angeles, Los Angeles, California (D.W.H.)
| | - Gijs R van den Brink
- Department of Gastroenterology and Hepatology, Tytgat Institute for Liver and Intestinal Research, Academic Medical Center, Amsterdam, The Netherlands (A.P.V., M.E.W., G.R.v.d.B.); Department of Gastroenterology and Hepatology, Leiden University Medical Center, Leiden, The Netherlands (A.P.V., D.W.H.); Department of Gastroenterology and Hepatology, Erasmus University Medical Center, Rotterdam, The Netherlands (M.P.P.); and Center for Inflammatory Bowel Diseases, University of California Los Angeles, Los Angeles, California (D.W.H.)
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Hirschhäuser C, Velcicky J, Schlawe D, Hessler E, Majdalani A, Neudörfl JM, Prokop A, Wieder T, Schmalz HG. Nucleoside analogues with a 1,3-diene-Fe(CO)3 substructure: stereoselective synthesis, configurational assignment, and apoptosis-inducing activity. Chemistry 2013; 19:13017-29. [PMID: 23934861 DOI: 10.1002/chem.201301672] [Citation(s) in RCA: 17] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/01/2013] [Indexed: 01/09/2023]
Abstract
The synthesis and stereochemical assignment of two classes of iron-containing nucleoside analogues, both of which contain a butadiene-Fe(CO)3 substructure, is described. The first type of compounds are Fe(CO)3-complexed 3'-alkenyl-2',3'-dideoxy-2',3'-dehydro nucleosides (2,5-dihydrofuran derivatives), from which the second class of compounds is derived by formal replacement of the ring oxygen atom by a CH2 group (carbocyclic nucleoside analogues). These compounds were prepared in a stereoselective manner through the metal-assisted introduction of the nucleobase. Whilst the furanoid intermediates were prepared from carbohydrates (such as methyl-glucopyranoside), the carbocyclic compounds were obtained by using an intramolecular Pauson-Khand reaction. Stereochemical assignments based on NMR and CD spectroscopy were confirmed by X-ray structural analysis. Biological investigations revealed that several of the complexes exhibited pronounced apoptosis-inducing properties (through an unusual caspase 3-independent but ROS-dependent pathway). Furthermore, some structure-activity relationships were identified, also as a precondition for the design and synthesis of fluorescent and biotin-labeled conjugates.
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Affiliation(s)
- Christoph Hirschhäuser
- Department of Chemistry, University of Cologne, Greinstrasse 4, 50939 Köln (Germany), Fax: (+49) 221-470-3064
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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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Thakur A, Joshi N, Shanmugam T, Banerjee R. Proapoptotic miltefosine nanovesicles show synergism with paclitaxel: Implications for glioblastoma multiforme therapy. Cancer Lett 2012; 334:274-83. [PMID: 22935677 DOI: 10.1016/j.canlet.2012.08.022] [Citation(s) in RCA: 20] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/20/2012] [Revised: 08/13/2012] [Accepted: 08/20/2012] [Indexed: 11/19/2022]
Abstract
Hexadecylphosphocholine (HePC) or miltefosine based proapoptotic lipid nanovesicles encapsulating paclitaxel for synergistic anticancer effect of paclitaxel and miltefosine in chemoresistant human glioblastoma multiforme (U-87 MG) overexpressing multidrug resistance 1 (MDR1) gene product P-glycoprotein (P-gp), were developed in this study. The nanovesicles had 100-200nm size and a negative zeta potential (∼-25mV) and optimized for miltefosine content based on their physiochemical properties. With a high encapsulation efficiency of 94%, the nanovesicles showed sustained release of paclitaxel in nasal fluid and triggered release in the cerebrospinal fluid. Synergistic action of paclitaxel and miltefosine was observed with a low IC50 of 162±5nM. The nanovesicle also overcame drug resistance and showed ATP dependent uptake via clathrin mediated pathway in glioblastoma cells. An improved therapeutic efficacy in comparison to Taxol®, the current clinical formulation of paclitaxel was observed. Efficient brain uptake of the nanovesicles upon intranasal administration was observed in vivo and the nanovesicles were also found to be able to cross blood brain barrier. These studies therefore suggest the therapeutic potential of proapoptotic lipid nanovesicles and their feasibility for intranasal administration in the treatment of chemoresistant glioblastoma.
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Affiliation(s)
- Ankita Thakur
- WRCBB, Department of Biosciences and Bioengineering, Indian Institute of Technology Bombay, Powai, Mumbai 400 076, India
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Ultrastructural analysis of miltefosine-induced surface membrane damage in adult Schistosoma mansoni BH strain worms. Parasitol Res 2012; 110:2465-73. [DOI: 10.1007/s00436-011-2786-5] [Citation(s) in RCA: 37] [Impact Index Per Article: 3.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/31/2011] [Accepted: 12/13/2011] [Indexed: 02/07/2023]
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Wargo MJ, Gross MJ, Rajamani S, Allard JL, Lundblad LKA, Allen GB, Vasil ML, Leclair LW, Hogan DA. Hemolytic phospholipase C inhibition protects lung function during Pseudomonas aeruginosa infection. Am J Respir Crit Care Med 2011; 184:345-54. [PMID: 21562128 DOI: 10.1164/rccm.201103-0374oc] [Citation(s) in RCA: 59] [Impact Index Per Article: 4.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/31/2023] Open
Abstract
RATIONALE The opportunistic pathogen Pseudomonas aeruginosa causes both acute and chronic lung infections and is particularly problematic in patients with cystic fibrosis and those undergoing mechanical ventilation. Decreased lung function contributes significantly to morbidity and mortality during P. aeruginosa infection, and damage inflicted by P. aeruginosa virulence factors contributes to lung function decline. OBJECTIVES We sought to describe direct contribution of a bacterial phospholipase C/sphingomyelinase, PlcHR, to alteration of host lung physiology and characterize a potential therapeutic for protection of lung function. METHODS We infected C57Bl/6 mice with P. aeruginosa wild-type or isogenic plcHR deletion strains and measured lung function using computer-controlled ventilators. For in vivo testing, miltefosine was delivered intraperitoneally 1 hour after infection. Infection and respiratory endpoints were at 24 hours after infection. MEASUREMENTS AND MAIN RESULTS P. aeruginosa wild-type infection caused significant lung function impairment, whereas the effects of a ΔplcHR strain infection were much less severe. Surfactometry analysis of bronchoalveolar lavage fluid indicated that PlcHR decreased pulmonary surfactant function. Miltefosine has structural similarity to the PC and sphingomyelin substrates of PlcHR, and we found that it inhibits the cleavage of these choline-containing lipids in vitro. Miltefosine administration after P. aeruginosa infection limited the negative effects of PlcHR activity on lung function. CONCLUSIONS We have directly linked production of a single virulence factor in P. aeruginosa with effects on lung function, and demonstrated that the inhibitor miltefosine protects lung function from PlcHR-dependent surfactant dysfunction.
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Affiliation(s)
- Matthew J Wargo
- Department of Microbiology and Molecular Genetics, University of Vermont College of Medicine, Burlington, VT 05405, USA.
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von Haefen C, Wendt J, Semini G, Sifringer M, Belka C, Radetzki S, Reutter W, Daniel PT, Danker K. Synthetic glycosidated phospholipids induce apoptosis through activation of FADD, caspase-8 and the mitochondrial death pathway. Apoptosis 2011; 16:636-51. [DOI: 10.1007/s10495-011-0592-2] [Citation(s) in RCA: 19] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/27/2022]
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Lee SY, Peckermann I, Abinet E, Okuda J, Henze G, Prokop A. The rare-earth yttrium complex [YR(mtbmp)(thf)] triggers apoptosis via the extrinsic pathway and overcomes multiple drug resistance in leukemic cells. Med Oncol 2010; 29:235-42. [PMID: 21191668 DOI: 10.1007/s12032-010-9787-6] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/20/2010] [Accepted: 12/15/2010] [Indexed: 01/14/2023]
Abstract
A major problem in treating patients with acute lymphoblastic leukemia is the development of drug resistance. In the current study, we investigated the anticancer properties of the novel rare-earth yttrium complex [YR(mtbmp)(thf)] in various established cell lines, and moreover, we identified the involved apoptotic pathway. Further aim was to investigate whether synergistic effects could be reached in combination with the conventional drug vincristine. We used the yttrium complex [YR(mtbmp)(thf)] in cells of leukemia (Nalm-6) and lymphoma (BJAB) and identified the main mechanism of the apoptosis induction by measuring the amount of hypodiploid DNA via FACS Scan analysis. Exposure of BJAB cells to [YR(mtbmp)(thf)] led to a death receptor-mediated reduction of cell viability and induction of apoptosis. The independence of Bcl-2 expression supports the suggestion that the [YR(mtbmp)(thf)]-induced apoptosis is mainly mediated via the extrinsic pathway. The extensive anti-tumor activity of [YR(mtbmp)(thf)] could be underlined by its capability to overcome multiple drug resistance in leukemic cells (Nalm-6) that are characterized by an overexpression of P-glycoprotein. [YR(mtbmp)(thf)] in combination with the conventional drug vincristine displayed impressive synergistic effects. We demonstrate in vitro efficiency of [YR(mtbmp)(thf)] in cells of hematological malignancies and reveal its ability to be a possible agent for polychemotherapy.
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Affiliation(s)
- Soo-Young Lee
- Department of Pediatric Oncology/Hematology, University Medical Center Charité Berlin, 13353 Berlin, Germany.
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Onambele LA, Koth D, Czaplewska JA, Schubert US, Görls H, Yano S, Obata M, Gottschaldt M, Prokop A. Mitochondrial Mode of Action of a Thymidine-Based Cisplatin Analogue Breaks Resistance in Cancer Cells. Chemistry 2010; 16:14498-505. [DOI: 10.1002/chem.201000785] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/07/2022]
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Kater B, Hunold A, Schmalz HG, Kater L, Bonitzki B, Jesse P, Prokop A. Iron containing anti-tumoral agents: unexpected apoptosis-inducing activity of a ferrocene amino acid derivative. J Cancer Res Clin Oncol 2010; 137:639-49. [DOI: 10.1007/s00432-010-0924-6] [Citation(s) in RCA: 20] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/02/2010] [Accepted: 05/21/2010] [Indexed: 10/19/2022]
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Cakir Z, Saydam G, Sahin F, Baran Y. The roles of bioactive sphingolipids in resveratrol-induced apoptosis in HL60: acute myeloid leukemia cells. J Cancer Res Clin Oncol 2010; 137:279-86. [PMID: 20401667 DOI: 10.1007/s00432-010-0884-x] [Citation(s) in RCA: 31] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/24/2010] [Accepted: 03/22/2010] [Indexed: 12/28/2022]
Abstract
PURPOSE Acute promyelocytic leukemia results from a translocation between 15 and 17 chromosomes that produce PML/RARα fusion protein. PML/RARα inhibits differentiation of myeloid precursor cells at stem cell level. Resveratrol is a phytoalexin that exerts cytotoxic effects on cancer cells. Ceramides have crucial roles in cell growth, proliferation, differentiation, drug resistance, and apoptosis. In this study, we examined the possible cytotoxic effects of resveratrol on acute myeloid leukemia cells and determined the roles of ceramide-metabolizing genes in resveratrol-induced apoptosis, in addition to investigating the possibility of increasing the sensitivity of HL60 cells to resveratrol by manipulating sphingolipids. METHODS Cytotoxic effects of resveratrol, C8:ceramide, PDMP, and SK-1 inhibitor were determined by XTT cell proliferation assay. Changes in caspase-3 enzyme activity and mitochondrial membrane potential (MMP) were measured using caspase-3 colorimetric assay and JC-1 MMP detection kit. Expression levels of ceramide-metabolizing genes were examined by RT-PCR. RESULTS The results revealed that manipulations of ceramide metabolism toward generation or accumulation of apoptotic ceramides increased apoptotic effects of resveratrol in HL60 cells, synergistically. More importantly, gene expression analyses revealed that resveratrol-induced apoptosis via increasing expression levels of ceramide-generating genes and decreasing expression levels of antiapoptotic sphingosine kinase-1 and glucosylceramide synthase genes. CONCLUSION These results showed for the first time that increasing intracellular levels of ceramides by biochemical approaches has also increased sensitivity of HL60 cells to resveratrol. We also showed that resveratrol induces apoptosis through manipulating ceramide-metabolizing genes that resulted in the accumulation of ceramides in HL60 cells.
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Affiliation(s)
- Zeynep Cakir
- Department of Molecular Biology and Genetics, Faculty of Science, Izmir Institute of Technology, Gulbahce Campus, 35430 Urla, Izmir, Turkey
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Jiménez-López JM, Ríos-Marco P, Marco C, Segovia JL, Carrasco MP. Alterations in the homeostasis of phospholipids and cholesterol by antitumor alkylphospholipids. Lipids Health Dis 2010; 9:33. [PMID: 20338039 PMCID: PMC2859738 DOI: 10.1186/1476-511x-9-33] [Citation(s) in RCA: 34] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/09/2010] [Accepted: 03/25/2010] [Indexed: 11/15/2022] Open
Abstract
The alkylphospholipid analog miltefosine (hexadecylphosphocholine) is a membrane-directed antitumoral and antileishmanial drug belonging to the alkylphosphocholines, a group of synthetic antiproliferative agents that are promising candidates in anticancer therapy. A variety of mechanisms have been suggested to explain the actions of these compounds, which can induce apoptosis and/or cell growth arrest. In this review, we focus on recent advances in our understanding of the actions of miltefosine and other alkylphospholipids on the human hepatoma HepG2 cell line, with a special emphasis on lipid metabolism. Results obtained in our laboratory indicate that miltefosine displays cytostatic activity and causes apoptosis in HepG2 cells. Likewise, treatment with miltefosine produces an interference with the biosynthesis of phosphatidylcholine via both CDP-choline and phosphatidylethanolamine methylation. With regard to sphingolipid metabolism, miltefosine hinders the formation of sphingomyelin, which promotes intracellular accumulation of ceramide. We have demonstrated for the first time that treatment with miltefosine strongly impedes the esterification of cholesterol and that this effect is accompanied by a considerable increase in the synthesis of cholesterol, which leads to higher levels of cholesterol in the cells. Indeed, miltefosine early impairs cholesterol transport from the plasma membrane to the endoplasmic reticulum, causing a deregulation of cholesterol homeostasis. Similar to miltefosine, other clinically-relevant synthetic alkylphospholipids such as edelfosine, erucylphosphocholine and perifosine show growth inhibitory effects on HepG2 cells. All the tested alkylphospholipids also inhibit the arrival of plasma-membrane cholesterol to the endoplasmic reticulum, which induces a significant cholesterogenic response in these cells, involving an increased gene expression and higher levels of several proteins related to the pathway of biosynthesis as well as the receptor-mediated uptake of cholesterol. Thus, membrane-targeted alkylphospholipids exhibit a common mechanism of action through disruption of cholesterol homeostasis. The accumulation of cholesterol within the cell and the reduction in phosphatidylcholine and sphingomyelin biosyntheses certainly alter the ratio of choline-bearing phospholipids to cholesterol, which is critical for the integrity and functionality of specific membrane microdomains such as lipid rafts. Alkylphospholipid-induced alterations in lipid homeostasis with probable disturbance of the native membrane structure could well affect signaling processes vital to cell survival and growth.
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Affiliation(s)
- José M Jiménez-López
- Department of Biochemistry and Molecular Biology I, Faculty of Sciences, University of Granada, Av, Fuentenueva s/n, Granada, Spain
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Danker K, Reutter W, Semini G. Glycosidated phospholipids: uncoupling of signalling pathways at the plasma membrane. Br J Pharmacol 2010; 160:36-47. [PMID: 20331609 DOI: 10.1111/j.1476-5381.2009.00626.x] [Citation(s) in RCA: 25] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022] Open
Abstract
Cell expansion and metastasis are considered hallmarks of tumour progression. Therefore, efforts have been made to develop novel anti-cancer drugs that inhibit both the proliferation and the motility of tumour cells. Synthetic alkylphospholipids, compounds with aliphatic side chains that are ether linked to a glycerol backbone, are structurally derived from platelet-activating factor and represent a new class of drugs with anti-proliferative properties in tumour cells. These compounds do not interfere with the DNA or mitotic spindle apparatus of the cell. Instead, they are incorporated into cell membranes, where they accumulate and interfere with lipid metabolism and lipid-dependent signalling pathways. Recently, it has been shown that the most commonly studied alkylphospholipids inhibit proliferation by inducing apoptosis in malignant cells while leaving normal cells unaffected. This review focuses on a novel group of synthetic alkylphospholipids, the glycosidated phospholipids, which contain carbohydrates or carbohydrate-related molecules at the sn-2 position of the glycerol backbone. Members of this subfamily also exhibit anti-proliferative capacity and modulate the cell adhesion, differentiation, and migration of tumour cells. Among this group, Ino-C2-PAF shows the highest efficacy and low cytotoxicity. Apart from its anti-proliferative effect, Ino-C2-PAF strongly reduces cell motility via its inhibitory effect on the phosphorylation of the cytosolic tyrosine kinases FAK and Src. Signalling pathways under the control of the FAK/Src complex are normally required for both migration and proliferation and play a prominent role in tumour progression. We intend to highlight the potential of glycosidated phospholipids, especially Ino-C2-PAF, as a promising new group of drugs for the treatment of hyperproliferative and migration-based skin diseases.
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Affiliation(s)
- Kerstin Danker
- Charité-Universitaetsmedizin Berlin, Campus Mitte, Institut fuer Biochemie, Monbijoustr, Berlin.
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Gatidis S, Borst O, Föller M, Lang F. Effect of osmotic shock and urea on phosphatidylserine scrambling in thrombocyte cell membranes. Am J Physiol Cell Physiol 2010; 299:C111-8. [PMID: 20237147 DOI: 10.1152/ajpcell.00477.2009] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/13/2022]
Abstract
Blood passing the renal medulla enters a strongly hypertonic environment challenging functional properties and survival of blood cells. In erythrocytes, exposure to hyperosmotic shock stimulates Ca(2+) entry and ceramide formation with subsequent cell membrane scrambling, an effect partially reversed by high concentrations of Cl(-) or urea. Cell membrane scrambling with phosphatidylserine exposure is part of the procoagulant phenotype of platelets. Coagulation in the hypertonic renal medulla would jeopardize blood flow in the vasa recta. The present study thus explored whether hypertonic environment and urea modify phosphatidylserine exposure of human platelets. FACS analysis was employed to estimate cytosolic Ca(2+) activity with Fluo3 fluorescence, ceramide formation, P-selectin, and glycoprotein IIb/IIIa activation with fluorescent antibodies and phosphatidylserine exposure with annexin V-binding. The spontaneous platelet aggregation was measured by impedance aggregometry. Hyperosmotic shock (addition of 500 mM sucrose or 250 mM NaCl) significantly enhanced cytosolic Ca(2+) activity, ceramide formation, phosphatidylserine exposure, platelet degranulation, and aggregability. Addition of 500 mM urea to isotonic saline did not significantly modify cytosolic Ca(2+) activity, ceramide abundance, or annexin V-binding but significantly blunted the respective effects of hypertonic shock following addition of 500 mM sucrose. In isotonic solutions, both ceramide (20 microM) and Ca(2+) ionophore ionomycin (0.5 microM) increased annexin V-binding, effects again significantly blunted by 500 mM urea. Moreover, oxidative stress by addition of 0.5 mM peroxynitrite increased cytosolic Ca(2+) activity and triggered annexin V-binding, effects again blunted in the presence of 500 mM urea. The observations reveal that hyperosmotic shock and oxidative stress trigger a procoagulant platelet phenotype, an effect blunted by the presence of high urea concentrations.
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Affiliation(s)
- Sergios Gatidis
- Department of Physiology, University of Tübingen, Tübingen, Germany
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Dobroschke M, Geldmacher Y, Ott I, Harlos M, Kater L, Wagner L, Gust R, Sheldrick W, Prokop A. Cytotoxic Rhodium(III) and Iridium(III) Polypyridyl Complexes: Structure-Activity Relationships, Antileukemic Activity, and Apoptosis Induction. ChemMedChem 2009; 4:177-87. [DOI: 10.1002/cmdc.200800311] [Citation(s) in RCA: 49] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/10/2022]
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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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Hexadecylphosphocholine alters nonvesicular cholesterol traffic from the plasma membrane to the endoplasmic reticulum and inhibits the synthesis of sphingomyelin in HepG2 cells. Int J Biochem Cell Biol 2008; 41:1296-303. [PMID: 19084611 DOI: 10.1016/j.biocel.2008.11.004] [Citation(s) in RCA: 21] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/25/2008] [Revised: 11/11/2008] [Accepted: 11/11/2008] [Indexed: 01/05/2023]
Abstract
The synthetic lipid analogue, hexadecylphosphocholine is an antitumoral and antileishmanial agent that acts on cell membranes and can induce apoptosis. We have previously investigated the effect of hexadecylphosphocholine on the biosynthesis and intracellular transport of cholesterol in the human hepatoma HepG2 cell line. Here we show that the traffic of endocytosed-cholesterol from LDL to the plasma membrane and the transport of newly synthesized cholesterol from the endoplasmic reticulum to the plasma membrane were unaffected by alkylphosphocholine exposure. On the contrary, cholesterol traffic from the plasma membrane to the endoplasmic reticulum was drastically interrupted after 1 h of cell exposition to HePC and, consequently, the intracellular esterification of cholesterol was substantially decreased. Our results also demonstrate that this alkylphosphocholine exclusively affected the nonvesicular, energy-independent cholesterol traffic, without altering the vesicular transport. In addition, hydrolysis of plasma membrane sphingomyelin by exogenously added sphingomyelinase resulted in enhanced plasma-membrane cholesterol esterification, but sphingomyelinase treatment did not prevent the inhibition in cholesteryl ester formation caused by hexadecylphosphocholine. We also found that sphingomyelin synthesis was significantly inhibited in HepG2 cells after exposure to hexadecylphosphocholine. Since sphingomyelin and cholesterol are major lipid constituents of membrane raft microdomains, these results suggest that hexadecylphosphocholine could disturb membrane raft integrity and thence its functionality.
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Carrasco MP, Jiménez-López JM, Segovia JL, Marco C. Hexadecylphosphocholine interferes with the intracellular transport of cholesterol in HepG2 cells. FEBS J 2008; 275:1675-86. [DOI: 10.1111/j.1742-4658.2008.06322.x] [Citation(s) in RCA: 14] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/26/2022]
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Azzouz S, Maache M, Sánchez-Moreno M, Petavy AF, Osuna A. Effect of alkyl-lysophospholipids on some aspects of the metabolism of Leishmania donovani. J Parasitol 2008; 93:1202-7. [PMID: 18163358 DOI: 10.1645/ge-1086r1.1] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/10/2022] Open
Abstract
Alkyl-lysophospholipids (ALPs), developed initially to be antitumor agents, have proved highly effective in the treatment of visceral leishmaniasis, a disease caused by the species making up the protozoan complex Leishmania donovani. Although their effectiveness is known, the mode of action against this parasite is not completely understood. In the present work, we have studied the effect of 3 derivatives, edelfosine, miltefosine, and ilmofosine. Using nuclear magnetic resonance spectroscopy ('H-NMR), we have examined the excreted catabolites from glucose metabolism in the promastigote forms treated with these compounds. The ALPs at concentrations of 19 and 38 microM inhibit the excretion of acetate, succinate, and pyruvate. The effect of edelfosine, miltefosine, and ilmofosine on the activity of the enzymes hexokinase, glycerolkinase 3-PD, phosphoglucose isomerase, superoxide dismutase, and phospholipase C were also examined. Glycerolkinase 3-PD and phosphoglucose isomerase are generally insensitive to the compounds, whereas hexokinase and superoxide dismutase are inhibited by miltefosine and ilmofosine. The ALPs exhibited an activated effect against the phospholipase C activity. Alkyl-lysophospholipids were shown to have a significant effect on several enzymes in important biochemical pathways indispensable for the survival of L. donovani promasigotes.
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Affiliation(s)
- S Azzouz
- Institute of Biotechnology, Department of Parasitology, Faculty of Sciences Campus Fuentenueva CP, Granada, Spain
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40
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Obando D, Widmer F, Wright LC, Sorrell TC, Jolliffe KA. Synthesis, antifungal and antimicrobial activity of alkylphospholipids. Bioorg Med Chem 2007; 15:5158-65. [PMID: 17532639 DOI: 10.1016/j.bmc.2007.05.028] [Citation(s) in RCA: 25] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/11/2006] [Revised: 04/26/2007] [Accepted: 05/10/2007] [Indexed: 10/23/2022]
Abstract
The antifungal, antibacterial and haemolytic activity of a series of alkylphosphocholines (e.g., miltefosine) and alkylglycerophosphocholines (e.g., edelfosine) has been investigated. These compound classes exhibit significant antifungal and moderate antibacterial activities. Several new alkylphosphocholine derivatives with amide or ester bonds in the alkyl chain have been synthesised. These compounds show much lower haemolytic activity than miltefosine. Alkylphosphocholines and alkylglycerophosphocholines show significant promise as novel orally available antifungal and antibacterial therapeutics.
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Affiliation(s)
- Daniel Obando
- School of Chemistry, The University of Sydney, NSW, Australia
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41
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Paris C, Bertoglio J, Bréard J. Lysosomal and mitochondrial pathways in miltefosine-induced apoptosis in U937 cells. Apoptosis 2007; 12:1257-67. [PMID: 17347868 DOI: 10.1007/s10495-007-0052-1] [Citation(s) in RCA: 55] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/01/2022]
Abstract
Hexadecylphosphocholine (HePC) is an anticancer agent whose effect has been shown to involve apoptosis induction but the signaling pathways leading to apoptosis remain to be elucidated. We show here that HePC induces activation of caspase-9, -3, and -8 via the intrinsic pathway, release of cytochrome c, activation and relocation of Bax to the mitochondria as well as the cleavage of Bid. Moreover, a lysosomal pathway characterized by partial lysosomal rupture, cathepsin B activation and relocation from lysosomes to the cytosol, is involved in HePC-induced apoptosis. A cathepsin B/L inhibitor partially suppresses caspase activation and apoptosis induction, indicating signaling between lysosomes and mitochondria. Conversely, the pancaspase inhibitor Q-VD-OPH inhibits lysosomal rupture, but only at early time points, suggesting that immediate lysosomal rupture involves caspases. Overexpression of Bcl-2, an anti-apoptotic protein known to prevent mitochondrial dysfunction, totally abrogates lysosomal destabilization and cell death.
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Affiliation(s)
- Caroline Paris
- INSERM U749, Faculté de Pharmacie Paris-Sud. 5, rue Jean-Baptiste Clément 92290, Châtenay-Malabry, France
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42
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Seumois G, Fillet M, Gillet L, Faccinetto C, Desmet C, François C, Dewals B, Oury C, Vanderplasschen A, Lekeux P, Bureau F. De novo C16- and C24-ceramide generation contributes to spontaneous neutrophil apoptosis. J Leukoc Biol 2007; 81:1477-86. [PMID: 17329567 DOI: 10.1189/jlb.0806529] [Citation(s) in RCA: 59] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/24/2022] Open
Abstract
Neutrophils rapidly undergo spontaneous apoptosis following their release from the bone marrow. Although central to leukocyte homeostasis, the mechanisms that regulate neutrophil apoptosis remain poorly understood. We show here that apoptosis of cultured neutrophils is preceded by a substantial increase in the intracellular levels of 16 and 24 carbon atom (C(16)- and C(24))-ceramides, which are lipid second messengers of apoptosis and stress signaling. Treatment of neutrophils with fumonisin B(2), a selective inhibitor of the de novo pathway of ceramide synthesis, prevented accumulation of C(16)- and C(24)-ceramides. Moreover, fumonisin B(2) significantly reduced caspase-3, -8, and -9 activation and apoptosis in these cells. Conversely, 3-O-methylsphingomyelin and fantofarone, which are specific inhibitors of neutral and acid sphingomyelinases, respectively, neither inhibited C(16)- and C(24)-ceramide production nor decreased the apoptosis rate in neutrophils, indicating that in these cells, ceramides are not generated from membrane sphingomyelin. Further experiments showed that increasing endogenous C(16)- and C(24)-ceramide levels by using DL-threo-1-phenyl-2-palmitoylamino-3-morpholino-1-propanol and (1S,2R)-D-erythro-2-(N-myristoylamino)-1-phenyl-1-propanol, two inhibitors of ceramide metabolism, enhances caspase-3, -8, and -9 activity and increases neutrophil apoptosis. Similarly, apoptosis was induced rapidly when synthetic C(16)- and/or C(24)-ceramides were added to neutrophil cultures. Finally, GM-CSF, a cytokine that delays neutrophil apoptosis, abrogated C(16)- and C(24)-ceramide accumulation totally in cultured neutrophils, whereas Fas ligation accelerated apoptosis in these cells without affecting de novo ceramide production. We conclude that de novo generation of C(16)- and C(24)-ceramides contributes to spontaneous neutrophil apoptosis via caspase activation and that GM-CSF exerts its antiapoptotic effects on neutrophils, at least partly through inhibition of ceramide accumulation.
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Affiliation(s)
- Grégory Seumois
- Department of Physiology, University of Liège, Boulevard de Colonster, Bâtiment B42, Sart-Tilman, B-4000, Liège, Belgium
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Takeda S, Mitsutake S, Tsuji K, Igarashi Y. Apoptosis occurs via the ceramide recycling pathway in human HaCaT keratinocytes. J Biochem 2007; 139:255-62. [PMID: 16452313 DOI: 10.1093/jb/mvj026] [Citation(s) in RCA: 32] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/12/2022] Open
Abstract
Keratinocytes contain abundant ceramides compared to other cells. However, studies on these cells have mainly focused on the barrier function of ceramide, while their other roles, such as those in apoptosis or cell cycle arrest, have not been well addressed. In this study, we investigated the apoptosis-inducing effect of exogenously added cell-permeable ceramides in HaCaT keratinocytes. We found that N-hexanoyl sphingosine (C6-ceramide) induced apoptosis efficiently through the accumulation of long chain ceramides. On the other hand, N-acetyl sphingosine (C2-ceramide) induced neither apoptosis nor accumulation of long chain ceramides. We also found that exogenously added C6-ceramide was hydrolyzed to sphingosine and then reacylated in long chain ceramides (ceramide recycling pathway), but that C2-ceramide was not hydrolyzed and thus not recycled. We propose that this is the basis for the chain length-specific heterogeneity observed in ceramide-induced apoptosis in these cells. These results also imply that keratinocytes utilize exogenous sphingolipids or ceramides to coordinate their own ceramide compositions.
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Affiliation(s)
- Saeko Takeda
- Department of Biomembrane and Biofunctional Chemistry, Graduate School of Pharmaceutical Sciences, Hokkaido University, Sapporo 060-0812, Japan
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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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Curfman CL, Kirkland K, Merrill AH. Recent anticancer agents targeting sphingolipid pathways. Expert Opin Ther Pat 2006. [DOI: 10.1517/13543776.16.8.1129] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/05/2022]
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Abstract
Suicidal death of erythrocytes (eryptosis) is characterized by cell shrinkage, membrane blebbing, activation of proteases, and phosphatidylserine exposure at the outer membrane leaflet. Exposed phosphatidylserine is recognized by macrophages that engulf and degrade the affected cells. Eryptosis is triggered by erythrocyte injury after several stressors, including oxidative stress. Besides caspase activation after oxidative stress, two signaling pathways converge to trigger eryptosis: (a) formation of prostaglandin E(2) leads to activation of Ca(2+)-permeable cation channels, and (b) the phospholipase A(2)-mediated release of platelet-activating factor activates a sphingomyelinase, leading to formation of ceramide. Increased cytosolic Ca(2+) activity and enhanced ceramide levels lead to membrane scrambling with subsequent phosphatidylserine exposure. Moreover, Ca(2+) activates Ca(2+)-sensitive K(2+) channels, leading to cellular KCl loss and cell shrinkage. In addition, Ca(2+) stimulates the protease calpain, resulting in degradation of the cytoskeleton. Eryptosis is inhibited by erythropoietin, which thus extends the life span of circulating erythrocytes. Eryptosis may be a mechanism of defective erythrocytes to escape hemolysis. Conversely, excessive eryptosis favors the development of anemia. Conditions with excessive eryptosis include iron deficiency, lead or mercury intoxication, sickle cell anemia, thalassemia, glucose 6- phosphate dehydrogenase deficiency, malaria, and infection with hemolysin-forming pathogens.
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Affiliation(s)
- Florian Lang
- Department of Physiology, Eberhard-Karls-University of Tübingen, Germany.
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Choubey V, Guha M, Maity P, Kumar S, Raghunandan R, Maulik PR, Mitra K, Halder UC, Bandyopadhyay U. Molecular characterization and localization of Plasmodium falciparum choline kinase. Biochim Biophys Acta Gen Subj 2006; 1760:1027-38. [PMID: 16626864 DOI: 10.1016/j.bbagen.2006.03.003] [Citation(s) in RCA: 30] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/14/2005] [Revised: 02/24/2006] [Accepted: 03/01/2006] [Indexed: 10/24/2022]
Abstract
Generation of phosphocholine by choline kinase is important for phosphatidylcholine biosynthesis via Kennedy pathway and phosphatidylcholine biosynthesis is essential for intraerythrocytic growth of malaria parasite. A putative gene (Gene ID PF14_0020) in chromosome 14, having highest sequence homology with choline kinase, has been identified by BLAST searches from P. falciparum genome sequence database. This gene has been PCR amplified, cloned, over-expressed and characterized. Choline kinase activity of the recombinant protein (PfCK) was validated as it catalyzed the formation of phosphocholine from choline in presence of ATP. The K(m) values for choline and ATP are found to be 145+/-20 microM and 2.5+/-0.3 mM, respectively. PfCK can phosphorylate choline efficiently but not ethanolamine. Southern blotting indicates that PfCK is a single copy gene and it is a cytosolic protein as evidenced by Western immunoblotting and confocal microscopy. A model structure of PfCK was constructed based on the crystal structure of choline kinase of C. elegans to search the structural homology. Consistent with the homology modeling predictions, CD analysis indicates that the alpha and beta content of PfCK are 33% and 14%, respectively. Since choline kinase plays a vital role for growth and multiplication of P. falciparum during intraerythrocytic stages, we can suggest that this well characterized PfCK may be exploited in the screening of new choline kinase inhibitors to evaluate their antimalarial activity.
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Affiliation(s)
- Vinay Choubey
- Division of Drug Target Discovery and Development, Central Drug Research Institute, Chatter Manzil Palace, Mahatma Gandhi Marg, Lucknow-226001, Uttar Pradesh, India
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Fischer A, Müller D, Zimmermann-Kordmann M, Kleuser B, Mickeleit M, Laabs S, Löwe W, Cantagrel F, Reutter W, Danker K. The ether lipid inositol-C2-PAF is a potent inhibitor of cell proliferation in HaCaT cells. Chembiochem 2006; 7:441-9. [PMID: 16453359 DOI: 10.1002/cbic.200500336] [Citation(s) in RCA: 17] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/10/2022]
Abstract
The search for specific anticancer drugs that do not interfere with DNA synthesis or influence the cytoskeleton has led to the development of modified phospholipids with antiproliferative properties. These compounds cause remodeling of the structure and function of plasma membranes. Recently, we described novel compounds, the glycosidated phospholipids, that surprisingly inhibit cell proliferation. These compounds contain alpha-D-glucose in the sn-2 position of the glycerol backbone of phosphatidylcholine (PC) and platelet-activating factor (PAF), which gives rise to 2-glucophosphatidylcholine (Glc-PC) and 1-O-octadecyl-2-O-alpha-d-glucopyranosyl-sn-2-glycero-3-phosphatidylcholine (Glc-PAF), respectively. Glc-PC and Glc-PAF inhibit the growth of HaCaT cells at nontoxic concentrations. Here we report the introduction of myo-inositol, in place of alpha-D-glucose, in the sn-2 position of the glycerol backbone; this leads to two diastereomeric 1-O-octadecyl-2-O-(2-(myo-inositolyl)-ethyl)-sn-glycero-3-(R/S)-phosphatidylcholines (Ino-C2-PAF). The inositol-containing PAF enhances the antiproliferative capacity (IC(50)=1.8 microM) and reduces the cytotoxicity relative to Glc-PAF (LC(50)=15 microM). Through biological assays, we showed that, in HaCaT cells, Ino-C2-PAF causes upregulation of the keratinocyte-specific differentiation marker involucrin, increases the activity of the differentiation marker transglutaminase, and induces apoptosis at nontoxic concentrations. Ino-C2-PAF therefore seems to be a promising candidate for development as an antiproliferative drug for the treatment of hyperproliferative diseases of the skin.
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Affiliation(s)
- Annette Fischer
- Charité-Universitätsmedizin Berlin, Campus Benjamin Franklin, Institut für Biochemie und Molekularbiologie, Arnimallee 22, 14195 Berlin-Dahlem, Germany
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Heczková B, Slotte JP. Effect of anti-tumor ether lipids on ordered domains in model membranes. FEBS Lett 2006; 580:2471-6. [PMID: 16638573 DOI: 10.1016/j.febslet.2006.03.079] [Citation(s) in RCA: 35] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/06/2006] [Revised: 03/21/2006] [Accepted: 03/21/2006] [Indexed: 11/29/2022]
Abstract
1-O-octadecyl-2-O-methyl-sn-glycero-3-phosphocholine (OMPC, edelfosine) and 1-hexadecylphosphocholine (HePC, miltefosine) represent two groups of synthetic ether lipid analogues with anti-tumor activity. Because of their hydrophobic nature, they may become incorporated into plasma membranes of cells, and it has been argued that they may act via association with lipid rafts. With the quenching of steady-state fluorescence of probes preferentially partitioning into sterol-rich ordered domains (cholestatrienol and trans-parinaric acid), we showed that OMPC and HePC by themselves did not form sterol-rich domains in fluid model membranes, in contrast to the two chain ether lipid 1,2-O-dihexadecyl-sn-glycero-3-phosphocholine. Nevertheless, all three ether lipids significantly stabilized palmitoyl-sphingomyelin/cholesterol-rich domains against temperature induced melting. In conclusion, this study shows that anti-tumor ether lipids are likely to affect the properties of cholesterol-sphingomyelin domains (i.e., lipid rafts) when incorporated into cell membranes.
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Affiliation(s)
- Bohdana Heczková
- Department of Biochemistry and Pharmacy, Abo Akademi University, Tykistokatu 6A, 20520 Turku, Finland.
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Sarri E, Garcia-Dorado D, Abellan A, Soler-Soler J. Effects of hypoxia, glucose deprivation and acidosis on phosphatidylcholine synthesis in HL-1 cardiomyocytes. CTP:phosphocholine cytidylyltransferase activity correlates with sarcolemmal disruption. Biochem J 2006; 394:325-34. [PMID: 16236026 PMCID: PMC1386031 DOI: 10.1042/bj20050834] [Citation(s) in RCA: 13] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/17/2022]
Abstract
A decrease in [3H]Cho (choline) incorporation in to PtdCho (phos-phatidylcholine) preceded the onset of LDH (lactate dehydrogenase) release in HL-1 cardiomyocytes submitted to simulated ischaemia. This observation led us to examine the role of PtdCho synthesis in sarcolemmal disruption in HL-1 cardiomyocytes. To address this objective we analysed the individual effects of hypoxia, glucose deprivation and acidosis, three prominent components of ischaemia, on the different steps of the Kennedy pathway for the synthesis of PtdCho. Pulse and pulse-chase experiments with [3H]Cho, performed in whole HL-1 cells submitted to hypoxia or normoxia, in the presence or absence of glucose at different pHs indicated first, that CK (choline kinase) was inhibited by hypoxia and acidosis, whereas glucose deprivation exacerbated the inhibition caused by hypoxia. Second, the rate-limiting reaction in PtdCho synthesis, catalysed by CCT (CTP:phosphocholine cytidylyltransferase), was inhibited by hypoxia and glucose deprivation, but unexpectedly activated by acidosis. In cellfree system assays, acidosis inhibited both CK and CCT. In experiments performed in whole cells, the effect of acidosis was likely to be direct on CK, but indirect or intact-cell-dependent on CCT. Since hypoxia and glucose deprivation favoured membrane disruption, but acidosis prevented it, we hypothesized that the modulation of CCT could be an important determinant of cell survival. Supporting this hypothesis, we show that CCT activity in whole-cell experiments clearly correlated with LDH release, but not with ATP concentration. Altogether our results suggest a significant role for CCT activity in sarcolemmal disruption during ischaemia.
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Affiliation(s)
- Elisabet Sarri
- Cardiology Service, Institut de Recerca Hospital Universitari Vall d'Hebron, Pg. Vall d'Hebron 119-129, 08035 Barcelona, Spain
| | - David Garcia-Dorado
- Cardiology Service, Institut de Recerca Hospital Universitari Vall d'Hebron, Pg. Vall d'Hebron 119-129, 08035 Barcelona, Spain
- To whom correspondence should be addressed (email )
| | - Arancha Abellan
- Cardiology Service, Institut de Recerca Hospital Universitari Vall d'Hebron, Pg. Vall d'Hebron 119-129, 08035 Barcelona, Spain
| | - Jordi Soler-Soler
- Cardiology Service, Institut de Recerca Hospital Universitari Vall d'Hebron, Pg. Vall d'Hebron 119-129, 08035 Barcelona, Spain
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