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Kumari G, Jain R, Kumar Sah R, Kalia I, Vashistha M, Singh P, Prasad Singh A, Samby K, Burrows J, Singh S. Multistage and transmission-blocking tubulin targeting potent antimalarial discovered from the open access MMV pathogen box. Biochem Pharmacol 2022; 203:115154. [PMID: 35798201 DOI: 10.1016/j.bcp.2022.115154] [Citation(s) in RCA: 4] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/23/2022] [Revised: 06/08/2022] [Accepted: 06/23/2022] [Indexed: 11/28/2022]
Abstract
The development of resistance to current antimalarial therapies remains a significant source of concern. To address this risk,newdrugswithnoveltargetsin distinct developmental stages ofPlasmodiumparasites are required. In the current study,we have targetedP. falciparumTubulin(PfTubulin)proteins which represent some of thepotentialdrug targetsfor malaria chemotherapy. PlasmodialMicrotubules (MTs) play a crucial role during parasite proliferation, growth, and transmission, which render them highlydesirabletargets for the development ofnext-generation chemotherapeutics. Towards this,we have evaluated the antimalarial activity ofTubulintargetingcompounds received from theMedicines for Malaria Venture (MMV)"Pathogen Box"against the human malaria parasite,P. falciparumincluding 3D7 (chloroquine and artemisinin sensitive strain), RKL-9 (chloroquine-resistant strain), and R539T (artemisinin-resistant strain). At nanomolar concentrations, the filtered-out compounds exhibitedpronouncedmultistage antimalarialeffects across the parasite life cycle, including intra-erythrocytic blood stages, liver stage parasites, gametocytes, and ookinetes. Concomitantly, these compoundswere found toimpedemale gamete ex-flagellation, thus showingtheir transmission-blocking potential. Target mining of these potent compounds, by combining in silico, biochemical and biophysical assays,implicatedPfTubulinas their moleculartarget, which may possibly act bydisruptingMT assembly dynamics by binding at the interface of α-βTubulin-dimer.Further, the promising ADME profile of the parent scaffold supported its consideration as a lead compound for further development.Thus, our work highlights the potential of targetingPfTubulin proteins in discovering and developing next-generation, multistage antimalarial agents against Multi-Drug Resistant (MDR) malaria parasites.
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Affiliation(s)
- Geeta Kumari
- Special Centre for Molecular Medicine, Jawaharlal Nehru University, New Delhi 110067, India
| | - Ravi Jain
- Special Centre for Molecular Medicine, Jawaharlal Nehru University, New Delhi 110067, India
| | - Raj Kumar Sah
- Special Centre for Molecular Medicine, Jawaharlal Nehru University, New Delhi 110067, India
| | | | - Manu Vashistha
- Advanced Instrumentation Research Facility, Jawaharlal Nehru University, New Delhi 110067, India
| | - Pooja Singh
- National Institute of Immunology, New Delhi 110067, India
| | | | | | | | - Shailja Singh
- Special Centre for Molecular Medicine, Jawaharlal Nehru University, New Delhi 110067, India.
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2
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Singh V, Hada RS, Jain R, Vashistha M, Kumari G, Singh S, Sharma N, Bansal M, Poonam, Zoltner M, Caffrey CR, Rathi B, Singh S. Designing and development of phthalimides as potent anti-tubulin hybrid molecules against malaria. Eur J Med Chem 2022; 239:114534. [PMID: 35749989 DOI: 10.1016/j.ejmech.2022.114534] [Citation(s) in RCA: 5] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/13/2021] [Revised: 06/06/2022] [Accepted: 06/11/2022] [Indexed: 11/03/2022]
Abstract
Constant emergence of drug-resistant Plasmodium falciparum warrants urgent need for effective and inexpensive drugs. Herein, phthalimide (Pht) analogs possessing the bioactive scaffolds, benzimidazole and 1,2,3-triazole, were evaluated for in vitro and in vivo anti-plasmodial activity without any apparent hemolysis, or cytotoxicity. Analogs 4(a-e) inhibited the growth of 3D7 and RKL-9 strains at submicromolar concentrations. Defects were observed during parasite egress from or invasion of the red blood cells. Mitochondrial membrane depolarization was measured as one of the causes of cell death. Phts 4(a-e) in combination with artemisinin exhibited two-to three-fold increased efficacy. Biophysical and biochemical analysis suggest that Pht analogs mediate plasmodial growth inhibition by interacting with tubulin protein of the parasite. Lastly, Phts 4(a-e) significantly decreased parasitemia and extended host survival in murine model Plasmodium berghei ANKA infection. Combined, the data indicate that Pht analogs should be further explored, which could offer novel value to the antimalarial drug development pipeline.
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Affiliation(s)
- Vigyasa Singh
- Special Centre for Molecular Medicine, Jawaharlal Nehru University, New Delhi, 110067, India
| | - Rahul Singh Hada
- Department of Life Sciences, Shiv Nadar University, Gautam Buddha Nagar, UP, 201314, India
| | - Ravi Jain
- Special Centre for Molecular Medicine, Jawaharlal Nehru University, New Delhi, 110067, India
| | - Manu Vashistha
- Advanced Instrumentation Research Facility, Jawaharlal Nehru University, New Delhi, 110067, India
| | - Geeta Kumari
- Special Centre for Molecular Medicine, Jawaharlal Nehru University, New Delhi, 110067, India
| | - Snigdha Singh
- Laboratory for Translational Chemistry and Drug Discovery, Department of Chemistry, Hansraj College, University of Delhi, Delhi, 110007, India
| | - Neha Sharma
- Laboratory for Translational Chemistry and Drug Discovery, Department of Chemistry, Hansraj College, University of Delhi, Delhi, 110007, India
| | - Meenakshi Bansal
- Laboratory for Translational Chemistry and Drug Discovery, Department of Chemistry, Hansraj College, University of Delhi, Delhi, 110007, India
| | - Poonam
- Department of Chemistry, Miranda House, University of Delhi, Delhi, 110007, India; Delhi School of Public Health, Institute of Eminence, University of Delhi, Delhi, 110007, India
| | - Martin Zoltner
- Drug Discovery and Evaluation Unit, Department of Parasitology, Faculty of Science, Charles University, BIOCEV, Vestec, Czech Republic
| | - Conor R Caffrey
- Center for Discovery and Innovation in Parasitic Diseases, Skaggs School of Pharmacy and Pharmaceutical Sciences, University of California San Diego, 9500 Gilman Drive, La Jolla, CA, 92093, USA
| | - Brijesh Rathi
- Laboratory for Translational Chemistry and Drug Discovery, Department of Chemistry, Hansraj College, University of Delhi, Delhi, 110007, India; Delhi School of Public Health, Institute of Eminence, University of Delhi, Delhi, 110007, India.
| | - Shailja Singh
- Special Centre for Molecular Medicine, Jawaharlal Nehru University, New Delhi, 110067, India.
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Nwonuma CO, Atanu FO, Okonkwo NC, Egharevba GO, Udofia IA, Evbuomwan IO, Alejolowo OO, Osemwegie OO, Adelani-Akande T, Dogunro FA. Evaluation of anti-malarial activity and GC–MS finger printing of cannabis: An in-vivo and in silico approach. SCIENTIFIC AFRICAN 2022. [DOI: 10.1016/j.sciaf.2022.e01108] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022] Open
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4
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Hirst WG, Fachet D, Kuropka B, Weise C, Saliba KJ, Reber S. Purification of functional Plasmodium falciparum tubulin allows for the identification of parasite-specific microtubule inhibitors. Curr Biol 2022; 32:919-926.e6. [PMID: 35051355 DOI: 10.1016/j.cub.2021.12.049] [Citation(s) in RCA: 14] [Impact Index Per Article: 7.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/27/2021] [Revised: 11/08/2021] [Accepted: 12/17/2021] [Indexed: 12/21/2022]
Abstract
Cytoskeletal proteins are essential for parasite proliferation, growth, and transmission, and therefore have the potential to serve as drug targets.1-5 While microtubules and their molecular building block αβ-tubulin are established drug targets in a variety of cancers,6,7 we still lack sufficient knowledge of the biochemistry of parasite tubulins to exploit the structural divergence between parasite and human tubulins. For example, it remains to be determined whether compounds of interest can specifically target parasite microtubules without affecting the host cell cytoskeleton. Such mechanistic insights have been limited by the lack of functional parasite tubulin. In this study, we report the purification and characterization of tubulin from Plasmodium falciparum, the causative agent of malaria. We show that the highly purified tubulin is fully functional, as it efficiently assembles into microtubules with specific parameters of dynamic instability. There is a high degree of amino-acid conservation between human and P. falciparum α- and β-tubulin, sharing approximately 83.7% and 88.5% identity, respectively. However, Plasmodium tubulin is more similar to plant than to mammalian tubulin, raising the possibility of identifying compounds that would selectively disrupt parasite microtubules without affecting the host cell cytoskeleton. As a proof of principle, we describe two compounds that exhibit selective toxicity toward parasite tubulin. Thus, the ability to specifically disrupt protozoan microtubule growth without affecting human microtubules provides an exciting opportunity for the development of novel antimalarials.
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Affiliation(s)
- William G Hirst
- IRI Life Sciences, Humboldt-Universität zu Berlin, 10115 Berlin, Germany; Research School of Biology, The Australian National University, Canberra, ACT 2601, Australia
| | - Dominik Fachet
- IRI Life Sciences, Humboldt-Universität zu Berlin, 10115 Berlin, Germany; Research School of Biology, The Australian National University, Canberra, ACT 2601, Australia
| | - Benno Kuropka
- Freie Universität Berlin, Institute of Chemistry and Biochemistry, Core Facility BioSupraMol, 14195 Berlin, Germany
| | - Christoph Weise
- Freie Universität Berlin, Institute of Chemistry and Biochemistry, Core Facility BioSupraMol, 14195 Berlin, Germany
| | - Kevin J Saliba
- Research School of Biology, The Australian National University, Canberra, ACT 2601, Australia
| | - Simone Reber
- IRI Life Sciences, Humboldt-Universität zu Berlin, 10115 Berlin, Germany; University of Applied Sciences Berlin, 13353 Berlin, Germany.
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Spreng B, Fleckenstein H, Kübler P, Di Biagio C, Benz M, Patra P, Schwarz US, Cyrklaff M, Frischknecht F. Microtubule number and length determine cellular shape and function in Plasmodium. EMBO J 2019; 38:e100984. [PMID: 31368598 PMCID: PMC6669926 DOI: 10.15252/embj.2018100984] [Citation(s) in RCA: 33] [Impact Index Per Article: 6.6] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/22/2018] [Revised: 04/12/2019] [Accepted: 04/26/2019] [Indexed: 11/27/2022] Open
Abstract
Microtubules are cytoskeletal filaments essential for many cellular processes, including establishment and maintenance of polarity, intracellular transport, division and migration. In most metazoan cells, the number and length of microtubules are highly variable, while they can be precisely defined in some protozoan organisms. However, in either case the significance of these two key parameters for cells is not known. Here, we quantitatively studied the impact of modulating microtubule number and length in Plasmodium, the protozoan parasite causing malaria. Using a gene deletion and replacement strategy targeting one out of two α-tubulin genes, we show that chromosome segregation proceeds in the oocysts even in the absence of microtubules. However, fewer and shorter microtubules severely impaired the formation, motility and infectivity of Plasmodium sporozoites, the forms transmitted by the mosquito, which usually contain 16 microtubules. We found that α-tubulin expression levels directly determined the number of microtubules, suggesting a high nucleation barrier as supported by a mathematical model. Infectious sporozoites were only formed in parasite lines featuring at least 10 microtubules, while parasites with 9 or fewer microtubules failed to transmit.
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Affiliation(s)
- Benjamin Spreng
- Integrative ParasitologyCenter for Infectious DiseasesHeidelberg University Medical SchoolHeidelbergGermany
| | - Hannah Fleckenstein
- Integrative ParasitologyCenter for Infectious DiseasesHeidelberg University Medical SchoolHeidelbergGermany
| | - Patrick Kübler
- Integrative ParasitologyCenter for Infectious DiseasesHeidelberg University Medical SchoolHeidelbergGermany
| | - Claudia Di Biagio
- Integrative ParasitologyCenter for Infectious DiseasesHeidelberg University Medical SchoolHeidelbergGermany
| | - Madlen Benz
- Integrative ParasitologyCenter for Infectious DiseasesHeidelberg University Medical SchoolHeidelbergGermany
| | - Pintu Patra
- Institute for Theoretical Physics and BioquantHeidelberg UniversityHeidelbergGermany
| | - Ulrich S Schwarz
- Institute for Theoretical Physics and BioquantHeidelberg UniversityHeidelbergGermany
| | - Marek Cyrklaff
- Integrative ParasitologyCenter for Infectious DiseasesHeidelberg University Medical SchoolHeidelbergGermany
| | - Friedrich Frischknecht
- Integrative ParasitologyCenter for Infectious DiseasesHeidelberg University Medical SchoolHeidelbergGermany
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Hallée S, Counihan NA, Matthews K, Koning‐Ward TF, Richard D. The malaria parasite
Plasmodium falciparum
Sortilin is essential for merozoite formation and apical complex biogenesis. Cell Microbiol 2018; 20:e12844. [DOI: 10.1111/cmi.12844] [Citation(s) in RCA: 16] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/22/2018] [Revised: 02/22/2018] [Accepted: 03/17/2018] [Indexed: 12/25/2022]
Affiliation(s)
- Stéphanie Hallée
- Centre de recherche en infectiologieCHU de Québec‐Université Laval Quebec City QC Canada
| | | | - Kathryn Matthews
- School of MedicineDeakin University Waurn Ponds 3216 VIC Australia
| | | | - Dave Richard
- Centre de recherche en infectiologieCHU de Québec‐Université Laval Quebec City QC Canada
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Johnson-Ajinwo OR, Ullah I, Mbye H, Richardson A, Horrocks P, Li WW. The synthesis and evaluation of thymoquinone analogues as anti-ovarian cancer and antimalarial agents. Bioorg Med Chem Lett 2018. [DOI: 10.1016/j.bmcl.2018.02.051] [Citation(s) in RCA: 31] [Impact Index Per Article: 5.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/06/2023]
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8
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Chasombat J, Nagai T, Parnpai R, Vongpralub T. Pretreatment of in vitro matured bovine oocytes with docetaxel before vitrification: Effects on cytoskeleton integrity and developmental ability after warming. Cryobiology 2015; 71:216-23. [PMID: 26192345 DOI: 10.1016/j.cryobiol.2015.07.002] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/28/2015] [Revised: 06/16/2015] [Accepted: 07/09/2015] [Indexed: 10/23/2022]
Abstract
The stabilization of spindle fibersis important for successful vitrification of bovine oocytes because microtubules and other cytoskeleton fibers (CSF) can be damaged during vitrification, resulting in failure of fertilization after thawing. Docetaxel, a stabilizing agent, could potentially reduce CSF damage of bovine oocytes induced during vitrification. However, there have been no reports on the effects of docetaxel on their vitrification. Experiment 1 was conducted to investigate the effects of various doses of docetaxel (0.0, 0.05, 0.5, 5.0 and 50 μM) in preincubation medium of in vitro matured (IVM) bovine oocytes on their developmental ability after in vitro fertilization (IVF). The results show that 0.05 μM docetaxel had no adverse effect on embryo development, while docetaxel at a concentration of ⩾0.5 μM inhibited development. Experiments 2 and 3 were conducted to investigate the effects of preincubation of IVM bovine oocytes with 0.05 μM docetaxel for 30 min prior to vitrification-warming on CSF integrity (Experiment 2), and on oocyte survival and viability after IVF (Experiment 3). When preincubated with 0.05 μM docetaxel for 30 min before vitrification, post-thawed oocytes had less CSF damage and higher survival rates compared with those untreated with docetaxel before vitrification. Surviving oocytes also had higher rates of cleavage and development to the blastocyst stage after IVF. In conclusion, preincubation of IVM bovine oocytes with 0.05 μM docetaxel for 30 min before vitrification was effective at preventing CSF damage during vitrification, and improving oocyte viability after warming and subsequent cleavage and blastocyst formation after IVF.
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Affiliation(s)
- Jakkhaphan Chasombat
- Department of Animal Science, Faculty of Agriculture, Khon Kaen University, Khon Kaen 40002, Thailand
| | - Takashi Nagai
- Food and Fertilizer Technology Center, Taipei 10648, Taiwan; NARO Institute of Livestock and Grassland Science, Tsukuba, Japan
| | - Rangsun Parnpai
- Embryo Technology and Stem Cell Research Center and School of Biotechnology, Suranaree University of Technology, Nakhon Ratchasima 30000, Thailand
| | - Thevin Vongpralub
- Department of Animal Science, Faculty of Agriculture, Khon Kaen University, Khon Kaen 40002, Thailand.
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9
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Mwande Maguene G, Lekana-Douki JB, Mouray E, Bousquet T, Grellier P, Pellegrini S, Toure Ndouo FS, Lebibi J, Pélinski L. Synthesis and in vitro antiplasmodial activity of ferrocenyl aminoquinoline derivatives. Eur J Med Chem 2015; 90:519-25. [DOI: 10.1016/j.ejmech.2014.11.065] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/26/2014] [Revised: 10/30/2014] [Accepted: 11/30/2014] [Indexed: 11/26/2022]
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10
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Chakrabarti R, Rawat PS, Cooke BM, Coppel RL, Patankar S. Cellular effects of curcumin on Plasmodium falciparum include disruption of microtubules. PLoS One 2013; 8:e57302. [PMID: 23505424 PMCID: PMC3591428 DOI: 10.1371/journal.pone.0057302] [Citation(s) in RCA: 42] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/01/2012] [Accepted: 01/21/2013] [Indexed: 12/17/2022] Open
Abstract
Curcumin has been widely investigated for its myriad cellular effects resulting in reduced proliferation of various eukaryotic cells including cancer cells and the human malaria parasite Plasmodium falciparum. Studies with human cancer cell lines HT-29, Caco-2, and MCF-7 suggest that curcumin can bind to tubulin and induce alterations in microtubule structure. Based on this finding, we investigated whether curcumin has any effect on P. falciparum microtubules, considering that mammalian and parasite tubulin are 83% identical. IC50 of curcumin was found to be 5 µM as compared to 20 µM reported before. Immunofluorescence images of parasites treated with 5 or 20 µM curcumin showed a concentration-dependent effect on parasite microtubules resulting in diffuse staining contrasting with the discrete hemispindles and subpellicular microtubules observed in untreated parasites. The effect on P. falciparum microtubules was evident only in the second cycle for both concentrations tested. This diffuse pattern of tubulin fluorescence in curcumin treated parasites was similar to the effect of a microtubule destabilizing drug vinblastine on P. falciparum. Molecular docking predicted the binding site of curcumin at the interface of alpha and beta tubulin, similar to another destabilizing drug colchicine. Data from predicted drug binding is supported by results from drug combination assays showing antagonistic interactions between curcumin and colchicine, sharing a similar binding site, and additive/synergistic interactions of curcumin with paclitaxel and vinblastine, having different binding sites. This evidence suggests that cellular effects of curcumin are at least, in part, due to its perturbing effect on P. falciparum microtubules. The action of curcumin, both direct and indirect, on P. falciparum microtubules is discussed.
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Affiliation(s)
- Rimi Chakrabarti
- Department of Biosciences and Bioengineering, Indian Institute of Technology Bombay (IITB), Mumbai, India
- Department of Microbiology, Monash University, Melbourne, Victoria, Australia
- IITB-Monash Research Academy, IIT Bombay, Mumbai, Maharashtra, India
| | - Parkash S. Rawat
- Department of Biosciences and Bioengineering, Indian Institute of Technology Bombay (IITB), Mumbai, India
| | - Brian M. Cooke
- Department of Microbiology, Monash University, Melbourne, Victoria, Australia
| | - Ross L. Coppel
- Department of Microbiology, Monash University, Melbourne, Victoria, Australia
| | - Swati Patankar
- Department of Biosciences and Bioengineering, Indian Institute of Technology Bombay (IITB), Mumbai, India
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11
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From a cytotoxic agent to the discovery of a novel antimalarial agent. Bioorg Med Chem Lett 2013; 23:584-7. [DOI: 10.1016/j.bmcl.2012.10.126] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/19/2012] [Revised: 10/26/2012] [Accepted: 10/29/2012] [Indexed: 11/24/2022]
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12
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Das S, Basu H, Korde R, Tewari R, Sharma S. Arrest of nuclear division in Plasmodium through blockage of erythrocyte surface exposed ribosomal protein P2. PLoS Pathog 2012; 8:e1002858. [PMID: 22912579 PMCID: PMC3415463 DOI: 10.1371/journal.ppat.1002858] [Citation(s) in RCA: 21] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/14/2012] [Accepted: 06/27/2012] [Indexed: 12/24/2022] Open
Abstract
Malaria parasites reside inside erythrocytes and the disease manifestations are linked to the growth inside infected erythrocytes (IE). The growth of the parasite is mostly confined to the trophozoite stage during which nuclear division occurs followed by the formation of cell bodies (schizogony). The mechanism and regulation of schizogony are poorly understood. Here we show a novel role for a Plasmodium falciparum 60S stalk ribosomal acidic protein P2 (PfP2) (PFC0400w), which gets exported to the IE surface for 6-8 hrs during early schizogony, starting around 26-28 hrs post-merozoite invasion. The surface exposure is demonstrated using multiple PfP2-specific monoclonal antibodies, and is confirmed through transfection using PfP2-GFP. The IE surface-exposed PfP2-protein occurs mainly as SDS-resistant P2-homo-tetramers. Treatment with anti-PfP2 monoclonals causes arrest of IEs at the first nuclear division. Upon removal of the antibodies, about 80-85% of synchronized parasites can be released even after 24 hrs of antibody treatment. It has been reported that a tubovesicular network (TVN) is set up in early trophozoites which is used for nutrient import. Anti-P2 monoclonal antibodies cause a complete fragmentation of TVN by 36 hrs, and impairs lipid import in IEs. These may be downstream causes for the cell-cycle arrest. Upon antibody removal, the TVN is reconstituted, and the cell division progresses. Each of the above properties is observed in the rodent malaria parasite species P. yoelii and P. berghei. The translocation of the P2 protein to the IE surface is therefore likely to be of fundamental importance in Plasmodium cell division.
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Affiliation(s)
- Sudipta Das
- Department of Biological Sciences, Tata Institute of Fundamental Research, Mumbai, India
| | - Himanish Basu
- Department of Biological Sciences, Tata Institute of Fundamental Research, Mumbai, India
| | - Reshma Korde
- Department of Biological Sciences, Tata Institute of Fundamental Research, Mumbai, India
| | - Rita Tewari
- Centre for Genetics and Genomics, Queen's Medical Centre, The University of Nottingham, Nottingham, United Kingdom
| | - Shobhona Sharma
- Department of Biological Sciences, Tata Institute of Fundamental Research, Mumbai, India
- * E-mail:
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13
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Chatterji BP, Jindal B, Srivastava S, Panda D. Microtubules as antifungal and antiparasitic drug targets. Expert Opin Ther Pat 2011; 21:167-86. [PMID: 21204724 DOI: 10.1517/13543776.2011.545349] [Citation(s) in RCA: 29] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/05/2022]
Abstract
INTRODUCTION Diseases caused by fungi and parasites are major illnesses in humans as well as in animals. Microtubule-targeted drugs are highly effective for the treatment of fungal and parasitic infections; however, several human parasitic infections such as malaria, trypanosomiasis and leishmaniasis do not have effective remedial drugs. In addition, the emergence of drug-resistant fungi and parasites makes the discovery of new drugs imperative. AREAS COVERED This article describes similarities and dissimilarities between parasitic, fungal and mammalian tubulins and focuses on microtubule-targeting agents and therapeutic approaches for the treatment of fungal and parasitic diseases. New microtubule-targeted antileishmanial, antimalarial and antifungal drugs, with structures, biological activities and related patents, are described. The potential of dsRNA against tubulin to inhibit proliferation of protozoan and helminthic parasites is also discussed. Patent documents up to 2010 have been searched on USPTO, Patentscope, and Espacenet resources. EXPERT OPINION The article suggests that vaccination with tubulin may offer novel opportunities for the antiparasitic treatment. Native or recombinant tubulin used as antigen has been shown to elicit immune response and cure infection partially or fully in animals upon challenge by protozoan parasites and helminths, thus indicating the suitability of tubulin as a vaccine against parasitic diseases.
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Affiliation(s)
- Biswa Prasun Chatterji
- Indian Institute of Technology Bombay, Department of Biosciences and Bioengineering, Powai, Mumbai-400076, India
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14
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Arnot DE, Ronander E, Bengtsson DC. The progression of the intra-erythrocytic cell cycle of Plasmodium falciparum and the role of the centriolar plaques in asynchronous mitotic division during schizogony. Int J Parasitol 2010; 41:71-80. [PMID: 20816844 DOI: 10.1016/j.ijpara.2010.07.012] [Citation(s) in RCA: 86] [Impact Index Per Article: 6.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/22/2010] [Revised: 07/22/2010] [Accepted: 07/23/2010] [Indexed: 12/11/2022]
Abstract
The cell division cycle and mitosis of intra-erythrocytic (IE) Plasmodium falciparum are poorly understood aspects of parasite development which affect malaria molecular pathogenesis. Specifically, the timing of the multiple gap (G), DNA synthesis (S) and chromosome separation (M) phases of parasite mitosis are not well defined, nor whether genome divisions are immediately followed by cleavage of the nuclear envelope. Curiously, daughter merozoite numbers do not follow the geometric expansion expected from equal numbers of binary divisions, an outcome difficult to explain using the standard model of cell cycle regulation. Using controlled synchronisation techniques, confocal microscopy to visualise key organelles and fluorescence in situ hybridization (FISH) to follow the movements and replication of genes and telomeres, we have re-analysed the timing and progression of mitotic events. The asynchronous duplications of the P. falciparum centrosome equivalents, the centriolar plaques, are established and these are correlated with chromosome and nuclear divisions in a new model of P. falciparum schizogony. Our results improve the resolution of the cell cycle and its phases during P. falciparum IE development, showing that asynchronous, independent nuclear division occurs during schizogony, with the centriolar plaques playing a major role in regulating mitotic progression.
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Affiliation(s)
- David E Arnot
- Centre for Medical Parasitology, Department of International Health, Immunology and Microbiology, Faculty of Health Sciences, University of Copenhagen, 1014 København K, Denmark.
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15
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Nzila A, Okombo J, Becker RP, Chilengi R, Lang T, Niehues T. Anticancer agents against malaria: time to revisit? Trends Parasitol 2010; 26:125-9. [PMID: 20056487 PMCID: PMC2927876 DOI: 10.1016/j.pt.2009.12.002] [Citation(s) in RCA: 22] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/24/2009] [Revised: 10/23/2009] [Accepted: 12/11/2009] [Indexed: 11/17/2022]
Abstract
The emergence of artemisinin resistance could adversely impact the current strategy for malaria treatment; thus, new drugs are urgently needed. A possible approach to developing new antimalarials is to find new uses for old drugs. Some anticancer agents such as methotrexate and trimetrexate are active against malaria. However, they are commonly perceived to be toxic and thus not suitable for malaria treatment. In this opinion article, we examine how the toxicity of anticancer agents is just a matter of dose or ‘only dose makes the poison’, as coined in Paracelsus’ law. Thus, the opportunity exists to discover new antimalarials using the anticancer pharmacopoeia.
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Affiliation(s)
- Alexis Nzila
- Kenya Medical Research Institute (KEMRI)/Wellcome Trust Collaborative Research Programme, Kilifi, Kenya.
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16
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Madelaine C, Buriez O, Crousse B, Florent I, Grellier P, Retailleau P, Six Y. Aminocyclopropanes as precursors of endoperoxides with antimalarial activity. Org Biomol Chem 2010; 8:5591-601. [DOI: 10.1039/c0ob00308e] [Citation(s) in RCA: 23] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
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17
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Accumulation of the antimalarial microtubule inhibitors trifluralin and vinblastine by Plasmodium falciparum. Biochem Pharmacol 2008; 75:1580-7. [DOI: 10.1016/j.bcp.2008.01.002] [Citation(s) in RCA: 13] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/08/2007] [Revised: 01/02/2008] [Accepted: 01/04/2008] [Indexed: 11/23/2022]
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18
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Isotype expression, post-translational modification and stage-dependent production of tubulins in erythrocytic Plasmodium falciparum. Int J Parasitol 2008; 38:527-39. [DOI: 10.1016/j.ijpara.2007.09.005] [Citation(s) in RCA: 31] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/09/2007] [Revised: 08/02/2007] [Accepted: 09/17/2007] [Indexed: 11/17/2022]
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19
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Githui EK, De Villiers EP, McArthur AG. Plasmodium possesses dynein light chain classes that are unique and conserved across species. INFECTION GENETICS AND EVOLUTION 2008; 9:337-43. [PMID: 18467191 DOI: 10.1016/j.meegid.2008.03.002] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/15/2007] [Revised: 03/09/2008] [Accepted: 03/16/2008] [Indexed: 10/22/2022]
Abstract
Plasmodium belongs to the phylum Apicomplexa. Within the Apicomplexa, Plasmodium, Toxoplasma and Cryptosporidium are parasites of considerable medical importance while Theileria and Eimeria are animal pathogens. P. falciparum is particularly important as it causes malaria, resulting in more than 1 million deaths each year. The malaria parasite actively invades the host cell in which it propagates and several proteins associated with the apical organelles have been implicated to be crucial in the invasion process. The biogenesis of the apical organelles is not well understood, but several studies indicate that microtubule-based vesicular transport is involved. Vesicular transport proteins are also present in Plasmodium and are presumed to be involved in transcellular transport in infected erythrocytes. Dynein is a multi-subunit motor protein involved in microtubule-based vesicular transport. In this study, we analyzed the cytoplasmic dynein light chains (Dlcs) of P. falciparum since they provide adaptor surface to the cargoes and are likely to be involved in differential transport. Dlcs consist of three different families: TcTex1/2, LC8 and LC7/roadblock. The data presented demonstrate that P. falciparum Dlcs sequences and functional domains show high sequence similarity within the species, but that only the Dlc group 1 (LC8) has a high similarity to human orthologues. TcTex1 and LC7/roadblock have low similarity to human orthologues. This sequence variation could be targeted for vaccine or drug development.
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Affiliation(s)
- Elijah K Githui
- Laboratory of Molecular Genetics, National Museums of Kenya, P.O. Box 40658, Nairobi, Kenya.
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20
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Olagnier D, Costes P, Berry A, Linas MD, Urrutigoity M, Dechy-Cabaret O, Benoit-Vical F. Modifications of the chemical structure of terpenes in antiplasmodial and antifungal drug research. Bioorg Med Chem Lett 2007; 17:6075-8. [PMID: 17904365 DOI: 10.1016/j.bmcl.2007.09.056] [Citation(s) in RCA: 29] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/31/2007] [Revised: 09/13/2007] [Accepted: 09/13/2007] [Indexed: 10/22/2022]
Abstract
Pure natural monoterpenes were evaluated in vitro for their antiplasmodial activities against Plasmodium falciparum. Chemically modified terpenes were also tested to see whether the introduction of an alkyne, a cyclopropane, a diene, or a cyclopentenone moiety had an influence on the biological activity. The IC(50) obtained on a chloroquine-resistant strain of Plasmodium (FcM29-Cameroon) showed moderate activity, but with the alkyne and the cyclopentenone derivatives showing a promising enhancement of activity compared with the parent molecules. On the contrary, no antifungal activity was found in vitro using Candida albicans. Given the observed antiplasmodial activity of some of these modified monoterpenes, new monoterpene derivatives could be the basis for new antimalarial drugs to be researched.
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Affiliation(s)
- David Olagnier
- Service de Parasitologie-Mycologie, CHU Rangueil, Toulouse 9, France
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21
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Abstract
The spread of parasitic resistance has necessitated the development of new drugs and drug targets for the treatment of malaria. Microtubules, which have gained outstanding importance as target molecules for the development of anticancer drugs, are likely to be potent antimalarial targets. The clinical implementation of microtubule inhibitors has given rise to a detailed mechanistic understanding of their interaction with tubulin on the molecular level and their effects on the cellular level. By comparison, our knowledge on Plasmodium falciparum, the causative agent of the most severe form of malaria, is rather poor. This article gives an overview on the microtubule inhibitors that have been explored in the parasite, reviews their effects on parasite growth and assesses their potential as novel antimalarials.
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Affiliation(s)
- Barbara Kappes
- Universitätsklinikum Heidelberg, Abteilung für Parasitologie, Im Neuenheimer Feld 324, Heidelberg, Germany.
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22
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Fennell BJ, Naughton JA, Dempsey E, Bell A. Cellular and molecular actions of dinitroaniline and phosphorothioamidate herbicides on Plasmodium falciparum: Tubulin as a specific antimalarial target. Mol Biochem Parasitol 2006; 145:226-38. [PMID: 16406111 DOI: 10.1016/j.molbiopara.2005.08.020] [Citation(s) in RCA: 68] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/13/2005] [Revised: 08/02/2005] [Accepted: 08/30/2005] [Indexed: 11/21/2022]
Abstract
Microtubules play important roles in cell division, motility and structural integrity of malarial parasites. Some microtubule inhibitors disrupt parasite development at very low concentrations, but most of them also kill mammalian cells. However, the dinitroaniline family of herbicides, which bind specifically to plant tubulin, have inhibitory activity on plant cells but are relatively non-toxic to human cells. Certain dinitroanilines are also inhibitory to various protozoal parasites including Plasmodium. Here we demonstrate that the dinitroanilines trifluralin and oryzalin inhibited progression of erythrocytic Plasmodium falciparum through schizogony, blocked mitotic division, and caused accumulation of abnormal microtubular structures. Moreover, radiolabelled trifluralin interacted with purified, recombinant parasite tubulins but to a much lesser extent with bovine tubulins. The phosphorothioamidate herbicide amiprophos-methyl, which has the same herbicidal mechanism as dinitroanilines, also had antimalarial activity and a similar action on schizogony. These data suggest that P. falciparum tubulin contains a dinitroaniline/phosphorothioamidate-binding site that is not conserved in humans and might be a target for new antimalarial drugs.
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Affiliation(s)
- Brian J Fennell
- Department of Microbiology, Moyne Institute of Preventive Medicine, The University of Dublin-Trinity College, Dublin, Ireland
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23
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Abstract
The Apicomplexa are a phylum of diverse obligate intracellular parasites including Plasmodium spp., the cause of malaria; Toxoplasma gondii and Cryptosporidium parvum, opportunistic pathogens of immunocompromised individuals; and Eimeria spp. and Theileria spp., parasites of considerable agricultural importance. These protozoan parasites share distinctive morphological features, cytoskeletal organization, and modes of replication, motility, and invasion. This review summarizes our current understanding of the cytoskeletal elements, the properties of cytoskeletal proteins, and the role of the cytoskeleton in polarity, motility, invasion, and replication. We discuss the unusual properties of actin and myosin in the Apicomplexa, the highly stereotyped microtubule populations in apicomplexans, and a network of recently discovered novel intermediate filament-like elements in these parasites.
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Affiliation(s)
- Naomi S Morrissette
- Department of Molecular Microbiology, Washington University School of Medicine, St. Louis, Missouri 63110, USA.
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24
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Rafatro H, Ramanitrahasimbola D, Rasoanaivo P, Ratsimamanga-Urverg S, Rakoto-Ratsimamanga A, Frappier F. Reversal activity of the naturally occurring chemosensitizer malagashanine in Plasmodium malaria. Biochem Pharmacol 2000; 59:1053-61. [PMID: 10704934 DOI: 10.1016/s0006-2952(99)00400-1] [Citation(s) in RCA: 22] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/27/2022]
Abstract
Malagashanine (MG) is the parent compound of a new type of indole alkaloids, the N(b)C(21)-secocuran, isolated so far from the Malagasy Strychnos species traditionally used as chloroquine adjuvants in the treatment of chronic malaria. Previously, it was shown to have weak in vitro intrinsic antiplasmodial activity (IC(50) = 146.5 +/- 0.2 microM), but did display marked in vitro chloroquine-potentiating action against the FcM29 chloroquine-resistant strain of Plasmodium falciparum. The purpose of the present study was to further investigate its reversal activity. Thus, the previous in vitro results were tested in vivo. The interaction of MG with several antimalarials against various strains of P. falciparum was also assessed. As expected, MG enhanced the effect of chloroquine against the resistant strain W2, but had no action on the susceptible strain 3D7 and two sensitive isolates. Interestingly, MG was found to exhibit significant chloroquine-potentiating action against the FcB1 strain formerly described as a resistant strain but one which has since lost its resistance for unknown reasons. One other relevant result that arose from our study was the observation of the selective enhancing action of MG on quinolines (chloroquine, quinine, and mefloquine), aminoacridines (quinacrine and pyronaridine), and a structurally unrelated drug (halofantrine), all of which are believed to exert their antimalarial effect by binding with haematin. MG was finally found to specifically act with chloroquine on the old trophozoite stage of the P. falciparum cycle. Similarities and differences between verapamil and MG reversal activity are briefly presented.
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Affiliation(s)
- H Rafatro
- Institut Malgache de Recherches Appliquées, B.P. 3833, 101, Antananarivo, Madagascar
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25
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Abstract
The need for new antimalarials comes from the widespread resistance to those in current use. New antimalarial targets are required to allow the discovery of chemically diverse, effective drugs. The search for such new targets and new drug chemotypes will likely be helped by the advent of functional genomics and structure-based drug design. After validation of the putative targets as those capable of providing effective and safe drugs, targets can be used as the basis for screening compounds in order to identify new leads, which, in turn, will qualify for lead optimization work. The combined use of combinatorial chemistry--to generate large numbers of structurally diverse compounds--and of high throughput screening systems--to speed up the testing of compounds--hopefully will help to optimize the process. Potential chemotherapeutic targets in the malaria parasite can be broadly classified into three categories: those involved in processes occurring in the digestive vacuole, enzymes involved in macromolecular and metabolite synthesis, and those responsible for membrane processes and signalling. The processes occurring in the digestive vacuole include haemoglobin digestion, redox processes and free radical formation, and reactions accompanying haem release followed by its polymerization into haemozoin. Many enzymes in macromolecular and metabolite synthesis are promising potential targets, some of which have been established in other microorganisms, although not yet validated for Plasmodium, with very few exceptions (such as dihydrofolate reductase). Proteins responsible for membrane processes, including trafficking and drug transport and signalling, are potentially important also to identify compounds to be used in combination with antimalarial drugs to combat resistance.
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Affiliation(s)
- P L Olliaro
- UNDP/World Bank/WHO Special Programme for Research and Training in Tropical Diseases, Geneva, Switzerland
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26
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Abstract
The Steering Committee on Drugs for Malaria (CHEMAL) of the UNDP/World Bank/WHO Special Programme for Research and Training in Tropical Diseases (TDR) has identified tubulin as a potential drug target, but one that is not yet ;validated'. Several inhibitors of tubulins, the principal proteins of microtubules, are potent inhibitors of the development and multiplication of malarial parasites in culture and in vivo. However, most of these compounds are also inhibitors of mammalian cell proliferation. Here, Angus Bell reviews the structure and properties of microtubules, their roles in Plasmodium cells, and the effects of various microtubule inhibitors on the parasite. He argues that microtubule inhibitors are not equally toxic to all proliferating cells but, by virtue of differential tubulin binding, show selective toxicity that might allow their use as antimalarial drugs.
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Affiliation(s)
- A Bell
- Department of Microbiology, Moyne Institute, Trinity College, Dublin 2, Ireland
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27
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Doherty TM, Sher A, Vogel SN. Paclitaxel (Taxol)-induced killing of Leishmania major in murine macrophages. Infect Immun 1998; 66:4553-6. [PMID: 9712819 PMCID: PMC108557 DOI: 10.1128/iai.66.9.4553-4556.1998] [Citation(s) in RCA: 16] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/23/1998] [Accepted: 06/16/1998] [Indexed: 11/20/2022] Open
Abstract
The antitumor drug paclitaxel (Taxol) has been demonstrated to be a lipopolysaccharide mimetic in murine macrophages. In this study, the capacity of paclitaxel to activate macrophages to become microbicidal for Leishmania major was examined. Paclitaxel and gamma interferon synergized to kill intracellular L. major in Lpsn, but not Lpsd, macrophages by a nitric oxide (NO.)-dependent mechanism.
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MESH Headings
- Animals
- Antigens, CD/genetics
- Antigens, CD/physiology
- Antiprotozoal Agents/pharmacology
- Cells, Cultured
- Female
- Interferon-gamma/pharmacology
- Leishmania major/drug effects
- Lipopolysaccharides/pharmacology
- Macrophages/metabolism
- Macrophages/parasitology
- Male
- Mice
- Mice, Inbred C3H
- Mice, Inbred C57BL
- Mice, Knockout
- Nitric Oxide/metabolism
- Nitric Oxide Synthase/genetics
- Nitric Oxide Synthase/physiology
- Nitric Oxide Synthase Type II
- Paclitaxel/pharmacology
- Receptors, Tumor Necrosis Factor/genetics
- Receptors, Tumor Necrosis Factor/physiology
- Receptors, Tumor Necrosis Factor, Type I
- Receptors, Tumor Necrosis Factor, Type II
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Affiliation(s)
- T M Doherty
- Immunobiology Section, Laboratory of Parasitic Diseases, National Institute of Allergy and Infectious Diseases, National Institutes of Health, Bethesda, Maryland 20892, USA
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28
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Sinou V, Boulard Y, Grellier P, Schrevel J. Host cell and malarial targets for docetaxel (Taxotere) during the erythrocytic development of Plasmodium falciparum. J Eukaryot Microbiol 1998; 45:171-83. [PMID: 9561771 DOI: 10.1111/j.1550-7408.1998.tb04522.x] [Citation(s) in RCA: 18] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Abstract
The microtubular stabilizing agent docetaxel (Taxotere) is known to inhibit the intraerythrocytic development of Plasmodium falciparum. To investigate the mechanism(s) of inhibition, we analyzed the structural organization of the mitotic spindle by immunofluorescence and electron microscopy. When 30 microM docetaxel was applied for five hours on ring forms, alterations in the mitotic spindles leading to abnormal nuclear divisions were observed. At the trophozoite- and schizont-stage, docetaxel pulses prevent mitosis by stabilizing microtubular structures associated with the mitotic apparatus, giving abnormal spindles. However, this inhibition did not interfere with parasite DNA synthesis indicating the absence of a checkpoint that couples exit from mitosis with proper spindle assembly as observed in higher eukaryotic cells. In parallel, intraerythrocytic concentration of docetaxel was measured in parasitized erythrocytes, after incubation of cells with 3H-docetaxel for five hours. It was found to be 14-fold increased at the ring-stage of infected erythrocytes compared to normal ones, 170-fold increased at the trophozoite-stage and 1,500-fold increased at the schizont-stage. Our data show that, even though the overall intracellular concentration of docetaxel is low in docetaxel-pulsed rings, the agent might be sufficient to disturb the spindle organization. However, the existence of targets for docetaxel other than mitotic spindle microtubules, i.e. erythrocyte membrane components could interfere with mitotic spindle formation.
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Affiliation(s)
- V Sinou
- Laboratoire de Biologie Parasitaire et Chimiothérapie, ERS-CNRS 156, Muséum National d'Histoire Naturelle, Paris, France
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29
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Taraschi TF, Trelka D, Schneider T, Matthews I. Plasmodium falciparum: characterization of organelle migration during merozoite morphogenesis in asexual malaria infections. Exp Parasitol 1998; 88:184-93. [PMID: 9562421 DOI: 10.1006/expr.1998.4254] [Citation(s) in RCA: 25] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022]
Abstract
Treatment of asexual Plasmodium falciparum infections with the microtubule stabilizing agents Taxol or epothilone A prevents the depolymerization of nuclear microtubules. Serial thin sectioning of treated parasites revealed the presence of polymerized nuclear microtubule assemblies extending from spindle pole bodies into the forming merozoites in late stage infections. This organization prevented daughter merozoites from pinching off the mother schizont during merogony. An electron-dense collar was apparent at the junction of the budding parasites and the schizont plasma membrane, suggesting the presence of a contractile, actin-myosin ring. Examination of Taxol or EpA arrested parasites provided new information about the merogonic process and the control of organelle migration. Drug treatment did not affect the migration or polarity of the rhoptries and micronemes. Ultrastructural characterization of drug-treated trophozoites identified an assembly of smooth vesicles and short tubules adjacent to the parasite nuclei. During merogony, these membranes were observed as flattened cisternae with dilated rims that appeared to be coated. The morphology and location of these membranes suggest that they may be the parasite Golgi apparatus. This investigation reveals that the antimalarial activity of microtubule stabilizing agents is due to their inhibition of merozoite formation.
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Affiliation(s)
- T F Taraschi
- Department of Pathology, Anatomy, and Cell Biology, Jefferson Medical College, Philadelphia, Pennsylvania 19107, USA.
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30
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Affiliation(s)
- M Hommel
- Liverpool School of Tropical Medicine, Liverpool, UK L3 5QA
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31
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Sinou V, Grellier P, Schrevel J. In vitro and in vivo inhibition of erythrocytic development of malarial parasites by docetaxel. Antimicrob Agents Chemother 1996; 40:358-61. [PMID: 8834880 PMCID: PMC163116 DOI: 10.1128/aac.40.2.358] [Citation(s) in RCA: 15] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/02/2023] Open
Abstract
The stage-dependent susceptibility of Plasmodium falciparum to a short exposure to docetaxel (Taxotere) was evaluated by subjecting ring-infected, trophozoite-infected, and schizont-infected erythrocytes to a 5-h exposure to various concentrations of the drug. The schizont stage was shown to be the most sensitive stage; an inhibition of more than 60% of parasite development was observed at 10 nM. At this drug concentration, the development of the younger ring and trophozoite forms was unaffected. The in vivo antimalarial activity of docetaxel against the development in blood of old trophozoites of a species that causes malaria in rodents, Plasmodium vinckei petteri, was evaluated in IOPS-OF1 mice. Two tests were performed: the 4-day suppressive test, as described by Peters (W. Peters, p. 145-273, in Chemotherapy, and Drug Resistance in Malaria, vol. 1, 1987), and the effects of a single injection of docetaxel after inoculation of the parasites. A single injection of docetaxel at 40 mg/kg of body weight was sufficient to reduce drastically the level of parasitemia; 90% inhibition of the development of parasites in blood was observed 5 days after drug injection. This program avoided the toxicity observed when mice were treated with four injections of docetaxel. The possibility of using a single bolus of taxoids to treat malaria infections is discussed.
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Affiliation(s)
- V Sinou
- Laboratoire de Biologie Parasitaire, Muséum National d'Histoire Naturelle, Paris, France
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