1
|
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
|
2
|
Gaillard N, Sharma A, Abbaali I, Liu T, Shilliday F, Cook AD, Ehrhard V, Bangera M, Roberts AJ, Moores CA, Morrissette N, Steinmetz MO. Inhibiting parasite proliferation using a rationally designed anti-tubulin agent. EMBO Mol Med 2021; 13:e13818. [PMID: 34661376 PMCID: PMC8573600 DOI: 10.15252/emmm.202013818] [Citation(s) in RCA: 12] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/08/2020] [Revised: 09/17/2021] [Accepted: 09/29/2021] [Indexed: 11/09/2022] Open
Abstract
Infectious diseases caused by apicomplexan parasites remain a global public health threat. The presence of multiple ligand-binding sites in tubulin makes this protein an attractive target for anti-parasite drug discovery. However, despite remarkable successes as anti-cancer agents, the rational development of protozoan parasite-specific tubulin drugs has been hindered by a lack of structural and biochemical information on protozoan tubulins. Here, we present atomic structures for a protozoan tubulin and microtubule and delineate the architectures of apicomplexan tubulin drug-binding sites. Based on this information, we rationally designed the parasite-specific tubulin inhibitor parabulin and show that it inhibits growth of parasites while displaying no effects on human cells. Our work presents for the first time the rational design of a species-specific tubulin drug providing a framework to exploit structural differences between human and protozoa tubulin variants enabling the development of much-needed, novel parasite inhibitors.
Collapse
Affiliation(s)
- Natacha Gaillard
- Laboratory of Biomolecular ResearchDivision of Biology and ChemistryPaul Scherrer InstitutVilligenSwitzerland
| | - Ashwani Sharma
- Laboratory of Biomolecular ResearchDivision of Biology and ChemistryPaul Scherrer InstitutVilligenSwitzerland
| | - Izra Abbaali
- Department of Molecular Biology and BiochemistryUniversity of CaliforniaIrvineCaliforniaUSA
| | - Tianyang Liu
- Institute of Structural and Molecular BiologyBirkbeck, University of LondonLondonUK
| | - Fiona Shilliday
- Institute of Structural and Molecular BiologyBirkbeck, University of LondonLondonUK
| | - Alexander D Cook
- Institute of Structural and Molecular BiologyBirkbeck, University of LondonLondonUK
| | - Valentin Ehrhard
- Laboratory of Biomolecular ResearchDivision of Biology and ChemistryPaul Scherrer InstitutVilligenSwitzerland
| | - Mamata Bangera
- Institute of Structural and Molecular BiologyBirkbeck, University of LondonLondonUK
| | - Anthony J Roberts
- Institute of Structural and Molecular BiologyBirkbeck, University of LondonLondonUK
| | - Carolyn A Moores
- Institute of Structural and Molecular BiologyBirkbeck, University of LondonLondonUK
| | - Naomi Morrissette
- Department of Molecular Biology and BiochemistryUniversity of CaliforniaIrvineCaliforniaUSA
| | - Michel O Steinmetz
- Laboratory of Biomolecular ResearchDivision of Biology and ChemistryPaul Scherrer InstitutVilligenSwitzerland
- Biozentrum University of BaselBaselSwitzerland
| |
Collapse
|
3
|
McEwan T, Robinson PC. A systematic review of the infectious complications of colchicine and the use of colchicine to treat infections. Semin Arthritis Rheum 2020; 51:101-112. [PMID: 33360321 PMCID: PMC7832726 DOI: 10.1016/j.semarthrit.2020.11.007] [Citation(s) in RCA: 10] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/15/2020] [Revised: 10/23/2020] [Accepted: 11/02/2020] [Indexed: 02/06/2023]
Abstract
Objective Colchicine has been used historically as an anti-inflammatory agent for a wide range of diseases. Little is known regarding the relationship between colchicine use and infectious disease outcomes. The objective of this study was to systematically examine infectious adverse events associated with colchicine usage and the clinical use of colchicine for infectious diseases. Methods A systematic review was conducted in accordance with PRISMA methodology. PubMed, EMBASE, Scopus and Cochrane Library databases were searched (up to 12th October, 2020) for interventional and observational studies that included colchicine usage associated with infectious adverse events or infectious disease outcomes. Results A total of 9,237 studies were initially identified and after exclusions, 36 articles comprising 21 interventional studies and 15 observational studies were included in this systematic review. There were 19 studies that reported infectious adverse events and 17 studies that examined the efficacy of colchicine in treating infectious disease. Only two out of six studies reported a significant benefit using colchicine in the management of viral liver disease. There was some evidence colchicine is beneficial in managing COVID-19 by reducing time to deterioration, length of stay in hospital and mortality. Colchicine had some benefit in managing malaria, condyloma accuminata and verruca vulgaris, viral myocarditis and erythema nodosum leprosum based on case-series or small, pilot clinical studies. Two of the clinical trials and five of the observational studies reported significant associations between infections adverse events and colchicine usage. Risk of pneumonia was found in three studies and post-operative infections were reported in two studies. Risks of urinary tract infections, H. pylori and C.difficile were only reported by one study each. Conclusion There is a current lack of clinical evidence that colchicine has a role in treating or managing infectious diseases. Preliminary studies have demonstrated a possible role in the management of COVID-19 but results from more clinical trials are needed. There is inconclusive evidence that suggests colchicine is associated with increased risk of infections, particularly pneumonia.
Collapse
Affiliation(s)
- Timothy McEwan
- University of Queensland School of Clinical Medicine, Queensland, Australia
| | - Philip C Robinson
- University of Queensland School of Clinical Medicine, Queensland, Australia.
| |
Collapse
|
4
|
Tcherniuk SO, Chesnokova O, Oleinikov IV, Potopalsky AI, Oleinikov AV. Anti-malarial effect of semi-synthetic drug amitozyn. Malar J 2015; 14:425. [PMID: 26515752 PMCID: PMC4625481 DOI: 10.1186/s12936-015-0952-4] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/04/2015] [Accepted: 10/21/2015] [Indexed: 11/12/2022] Open
Abstract
Background Malaria caused by Plasmodium falciparum is the most virulent form of malaria, leading to approximately a half million deaths per year. Chemotherapy continues to be a key approach in malaria prevention and treatment. Due to widespread parasite drug resistance, identification and development of new anti-malarial compounds remains an important task of malarial parasitology. The semi-synthetic drug amitozyn, obtained through alkylation of major celandine (Chelidonium majus) alkaloids with N,N′N′-triethylenethiophosphoramide (ThioTEPA), is a widely used Eastern European folk medicine for the treatment of various tumours. However, its anti-malarial effect has never been studied. Methods The anti-malarial effects of amitozyn alone and in combination with chloroquine, pyrimethamine and artemisinin on the blood stages of P. falciparum were analysed. The cytostatic effects of amitozyn on parasites and various cancerous and non-cancerous human cells were compared and their toxic effects on unparasitized human red blood cells were analysed. Results Obtained results demonstrate that amitozyn effectively inhibits the growth of blood-stage parasites with IC50 9.6 ± 2, 11.3 ± 2.8 and 10.8 ± 1.8 μg/mL using CS2, 3G8 and NF54 parasite lines, respectively. The median IC50 for 14 tested human cell lines was 33–152 μg/mL. Treatment of uninfected red blood cells with a high dose of amitozyn (500 μg/mL) did not change cell morphology, demonstrating its non-toxicity for erythrocytes. The synergistic impact of the amitozyn/chloroquine combination was observed at growth inhibition levels of 10–80 %, while demonstrating a nearly additive effect at a growth inhibition level of 90 %. The combination of amitozyn with pyrimethamine has a synergistic effect at growth inhibition levels of 10–70 % and a nearly additive effect at a growth inhibition level of 90 %. The synergistic anti-malarial effect of the amitozyn/artemisinin combination was observed at growth inhibition levels of 10–40 % and a nearly additive effect at growth inhibition levels of 50–90 %. Conclusions These in vitro results suggest that the semi-synthetic drug amitozyn, typically used for the treatment of tumours, is a potential anti-malarial candidate and warrants more detailed laboratory and pre-clinical investigations. Electronic supplementary material The online version of this article (doi:10.1186/s12936-015-0952-4) contains supplementary material, which is available to authorized users.
Collapse
Affiliation(s)
- Sergey O Tcherniuk
- Department of Biomedical Science, Charles E Schmidt College of Medicine, Florida Atlantic University, Boca Raton, FL, USA. .,Department of Biological Sciences, Youth Academy of Sciences, Kiev, Ukraine.
| | - Olga Chesnokova
- Department of Biomedical Science, Charles E Schmidt College of Medicine, Florida Atlantic University, Boca Raton, FL, USA.
| | - Irina V Oleinikov
- Department of Biomedical Science, Charles E Schmidt College of Medicine, Florida Atlantic University, Boca Raton, FL, USA.
| | - Anatoly I Potopalsky
- Institute of Molecular Biology and Genetics, National Academy of Sciences of Ukraine, Kiev, Ukraine. .,Institute of Health Promotion and Rebirth of People of Ukraine, Kiev, Ukraine.
| | - Andrew V Oleinikov
- Department of Biomedical Science, Charles E Schmidt College of Medicine, Florida Atlantic University, Boca Raton, FL, USA.
| |
Collapse
|
5
|
Del Cacho E, Gallego M, Lillehoj HS, Quílez J, Lillehoj EP, Ramo A, Sánchez-Acedo C. IL-17A regulates Eimeria tenella schizont maturation and migration in avian coccidiosis. Vet Res 2014; 45:25. [PMID: 24571471 PMCID: PMC3975951 DOI: 10.1186/1297-9716-45-25] [Citation(s) in RCA: 26] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/25/2013] [Accepted: 02/12/2014] [Indexed: 11/29/2022] Open
Abstract
Although IL17A is associated with the immunological control of various infectious diseases, its role in host response to Eimeria infections is not well understood. In an effort to better dissect the role of IL17A in host-pathogen interactions in avian coccidiosis, a neutralizing antibody (Ab) to chicken IL17A was used to counteract IL17A bioactivity in vivo. Chickens infected with Eimeria tenella and treated intravenously with IL17A Ab, exhibited reduced intracellular schizont and merozoite development, diminished lesion score, compared with untreated controls. Immunohistological evaluation of cecal lesions in the parasitized tissues indicated reduced migration and maturation of second-generation schizonts and reduced lesions in lamina propria and submucosa. In contrast, untreated and infected chickens had epithelial cells harboring second-generation schizonts, which extend into the submucosa through muscularis mucosa disruptions, maturing into second generation merozoites. Furthermore, IL17A Ab treatment was associated with increased parameters of Th1 immunity (IL2- and IFNγ- producing cells), reduced levels of reactive oxygen species (ROS), and diminished levels of serum matrix metalloproteinase-9 (MMP-9). Finally, schizonts from untreated and infected chickens expressed S100, Wiskott-Aldrich syndrome protein family member 3 (WASF3), and heat shock protein-70 (HSP70) proteins as merozoites matured, whereas the expression of these proteins was absent in IL17A Ab-treated chickens. These results provide the first evidence that the administration of an IL17A neutralizing Ab to E. tenella-infected chickens inhibits the migration of parasitized epithelial cells, markedly reduces the production of ROS and MMP-9, and decreases cecal lesions, suggesting that IL17A might be a potential therapeutic target for coccidiosis control.
Collapse
Affiliation(s)
- Emilio Del Cacho
- Department of Animal Pathology, Faculty of Veterinary Sciences, University of Zaragoza, Zaragoza, Spain.
| | | | | | | | | | | | | |
Collapse
|
6
|
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.
Collapse
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
| |
Collapse
|
7
|
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.
Collapse
Affiliation(s)
- Biswa Prasun Chatterji
- Indian Institute of Technology Bombay, Department of Biosciences and Bioengineering, Powai, Mumbai-400076, India
| | | | | | | |
Collapse
|
8
|
Abstract
SUMMARYThe invasive blood stage of malaria parasites, merozoites, are complex entities specialized for the capture and entry of red blood cells. Their potential for vaccination and other anti-malaria strategies have attracted much research attention over the last 40 years, and there is now a considerable body of data relating to their biology. In this article some of the major advances over this period and remaining challenges are reviewed.
Collapse
|
9
|
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.
Collapse
Affiliation(s)
- Elijah K Githui
- Laboratory of Molecular Genetics, National Museums of Kenya, P.O. Box 40658, Nairobi, Kenya.
| | | | | |
Collapse
|
10
|
Enger A, Strand ØA, Ranheim T, Hellum KB. Exflagellation of microgametocytes in Plasmodium vivax malaria: a diagnostic conundrum. Med Princ Pract 2004; 13:298-300. [PMID: 15316267 DOI: 10.1159/000079533] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 02/15/2003] [Accepted: 07/05/2003] [Indexed: 11/19/2022] Open
Abstract
OBJECTIVE To present a clinical diagnostic conundrum of unidentified structures in a blood smear from a patient with Plasmodium vivax malaria. CLINICAL PRESENTATION AND INTERVENTION A 37-year-old Ethiopian male presented with a 4-month history of chills, chronic diarrhea and weight loss. He was diagnosed with P. vivax malaria, advanced HIV infection and Isospora belli enteritis. Unidentified structures initially confusing to the diagnosticians were seen in blood smears taken on admission. The structures were initially considered to represent atypical spirochetes, but were later identified as microgametes and other exflagellation forms of P. vivax. The patient recovered after receiving adequate treatment for his infections. CONCLUSION This case illustrates that exflagellation may be observed in blood smears from patients with P. vivax malaria. Size and morphological characteristics differentiate malaria microgametes and other exflagellation forms from microfilaria, spirochetes and trypanosomes.
Collapse
Affiliation(s)
- Asle Enger
- Department of Medicine, Akershus University Hospital, Nordbyhagen, Norway
| | | | | | | |
Collapse
|
11
|
Bannister LH, Hopkins JM, Dluzewski AR, Margos G, Williams IT, Blackman MJ, Kocken CH, Thomas AW, Mitchell GH. Plasmodium falciparum apical membrane antigen 1 (PfAMA-1) is translocated within micronemes along subpellicular microtubules during merozoite development. J Cell Sci 2003; 116:3825-34. [PMID: 12902400 DOI: 10.1242/jcs.00665] [Citation(s) in RCA: 126] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022] Open
Abstract
During the assembly of Plasmodium falciparum merozoites within the schizont stage, the parasite synthesizes and positions three sets of secretory vesicles (rhoptries, micronemes and dense granules) that are active during red cell invasion. There are up to 40 micronemes per merozoite, shaped like long-necked bottles, about 160 nm long and 65 nm at their widest diameter. On their external surfaces, they bear bristle-like filaments, each 3-4 nm thick and 25 nm long. Micronemes are translocated from a single Golgi-like cisterna near the nucleus along a band of two or three subpellicular microtubules to the merozoite apex, where they dock with the rhoptry tips. Dense granules are also formed around the periphery of the Golgi cisternae but their distribution is unrelated to microtubules. Three polyclonal antibodies raised against the recombinant PfAMA-1 ectodomain sequence recognizing both the 83 kDa and processed 66 kDa molecules label the peripheries of translocating and mature micronemes but do not label rhoptries significantly at any stage of merozoite development within schizonts. This result confirms that PfAMA-1 is a micronemal protein, and indicates that within the microneme it is located near or inserted into this organelle's boundary membrane.
Collapse
Affiliation(s)
- Lawrence H Bannister
- Department of Anatomy, Cell and Human Biology, Guy's, King's and St Thomas' School of Biomedical Science, Guy's Hospital, London SE1 1UL, UK.
| | | | | | | | | | | | | | | | | |
Collapse
|
12
|
Morrissette NS, Sibley LD. Disruption of microtubules uncouples budding and nuclear division inToxoplasma gondii. J Cell Sci 2002; 115:1017-25. [PMID: 11870220 DOI: 10.1242/jcs.115.5.1017] [Citation(s) in RCA: 116] [Impact Index Per Article: 5.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022] Open
Abstract
The tachyzoite stage of the protozoan parasite Toxoplasma gondiihas two populations of microtubules: spindle microtubules and subpellicular microtubules. To determine how these two microtubule populations are regulated, we investigated microtubule behavior during the cell cycle following treatment with microtubule-disrupting drugs. Previous work had established that the microtubule populations are individually nucleated by two distinct microtubule-organizing centers (MTOCs): the apical polar ring for the subpellicular microtubules and spindle pole plaques/centrioles for the spindle microtubules. When replicating tachyzoites were treated with 0.5 μM oryzalin or 1.0 mM colchicine they retained the capacity to form a spindle and undergo nuclear division. Although these parasites could complete budding,they lost the bulk of their subpellicular microtubules and the ability to reinvade host cells. Both nascent spindle and subpellicular microtubules were disrupted in 2.5 μM oryzalin or 5.0 mM colchicine. Under these conditions,parasites grew in size and replicated their genome but were incapable of nuclear division. After removal from 0.5 μM oryzalin, Toxoplasmatachyzoites were able to restore normal subpellicular microtubules and a fully invasive phenotype. When oryzalin was removed from Toxoplasmatachyzoites treated with 2.5 μM drug, the parasites attempted to bud as crescent-shaped tachyzoites. Because the polyploid nuclear mass could not be correctly segregated, many daughter parasites lacked nuclei altogether although budding and scission from the maternal mass was able to be completed. Multiple MTOCs permit Toxoplasma tachyzoites to control nuclear division independently from cell polarity and cytokinesis. This unusual situation grants greater cell cycle flexibility to these parasites but abolishes the checks for coregulation of nuclear division and cytokinesis found in other eukaryotes.
Collapse
Affiliation(s)
- Naomi S Morrissette
- Department of Molecular Microbiology, Washington University School of Medicine, St. Louis MO 63110, USA.
| | | |
Collapse
|
13
|
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.
Collapse
Affiliation(s)
- Naomi S Morrissette
- Department of Molecular Microbiology, Washington University School of Medicine, St. Louis, Missouri 63110, USA.
| | | |
Collapse
|
14
|
Fowler RE, Smith AM, Whitehorn J, Williams IT, Bannister LH, Mitchell GH. Microtubule associated motor proteins of Plasmodium falciparum merozoites. Mol Biochem Parasitol 2001; 117:187-200. [PMID: 11606229 DOI: 10.1016/s0166-6851(01)00351-6] [Citation(s) in RCA: 28] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/16/2022]
Abstract
We have studied the occurrence, stage specificity and cellular location of key molecules associated with microtubules in Plasmodium falciparum merozoites. Antibodies to gamma tubulin, conventional kinesin and cytoplasmic dynein were used to determine the polarity of merozoite microtubules (mt), the stage specificity of the motor proteins and their location during merozoite development. We conclude that the minus ends of the mts are located at their apical pole. Kinesin was present throughout the lifecycle, appearing as a distinct crescent at the apex of developing merozoites. The vast majority of cytoplasmic dynein reactivity occurred in late merogony, also appearing at the merozoite apex. Destruction of mt with dinitroanilines did not affect the cellular location of kinesin or dynein. In invasion assays, dynein inhibitors reduced the number of ring stage parasites. Our results show that both conventional kinesin and cytoplasmic dynein are abundant, located at the negative pole of the merozoite mt and, intriguingly, appear there only in very late merogony, prior to merozoite release and invasion.
Collapse
Affiliation(s)
- R E Fowler
- Malaria Laboratory, Department of Immunobiology, Guy's, King's and St Thomas' School of Medicine, KCL, Guy's Hospital, London Bridge, London, SE1 9RT, UK.
| | | | | | | | | | | |
Collapse
|
15
|
Kumar S. Some in vitro invasion inhibition of red cells by in vivo nonprotective anti-LDH antibodies of Plasmodium berghei. JOURNAL OF VETERINARY MEDICINE. B, INFECTIOUS DISEASES AND VETERINARY PUBLIC HEALTH 2000; 47:481-6. [PMID: 11048428 DOI: 10.1046/j.1439-0450.2000.00316.x] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 04/15/2023]
Abstract
In Plasmodium berghei, sephadex G-200 purified lactate dehydrogenase (LDH) fraction immunized mice did not exhibit protection when challenged with 1 x 10(6) P. berghei-parasitized erythrocytes. However, LDH immunized mice seroconverted and showed an antibody titre of 1:2048 by indirect haemagglutination (IHA) and 1:160 by indirect fluorescent antibody (IFA) assays. Fluorescence was distributed evenly on P. berghei-parasitized red cells showing no specific location of parasite LDH. Anti-LDH antibodies supplemented in 19 h in vitro culture of P. berghei exhibited 9.2% invasion inhibition into the fresh red cells.
Collapse
Affiliation(s)
- S Kumar
- Department of Veterinary Microbiology, Punjab Agricultural University, Ludhiana, India
| |
Collapse
|
16
|
Pinder J, Fowler R, Bannister L, Dluzewski A, Mitchell GH. Motile systems in malaria merozoites: how is the red blood cell invaded? PARASITOLOGY TODAY (PERSONAL ED.) 2000; 16:240-5. [PMID: 10827429 DOI: 10.1016/s0169-4758(00)01664-1] [Citation(s) in RCA: 46] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
Abstract
The ability of the malaria parasite to invade erythrocytes is central to the disease process, but is not thoroughly understood. In particular, little attention has been paid to the motor systems driving invasion. Here, Jennifer Pinder, Ruth Fowler and colleagues review motility in the merozoite. The components of an actomyosin motor are present, including a novel unconventional class XIV myosin, now called Pfmyo-A, which, because of its time of synthesis and location, is likely to generate the force required for invasion. In addition, there is a subpellicular microtubule assemblage in falciparum merozoites, the f-MAST, the integrity of which is necessary for invasion.
Collapse
Affiliation(s)
- J Pinder
- MRC Muscle and Cell Motility Unit, Randall Institute, KCL, 26-29 Drury Lane, London, UK WC2B 5RL
| | | | | | | | | |
Collapse
|
17
|
López-Bernad F, del Cacho E, Gallego M, Quílez J, Sánchez-Acedo C. Immunohistochemical study of S100-like protein in Eimeria brunetti and Eimeria acervulina. Vet Parasitol 2000; 88:1-6. [PMID: 10681017 DOI: 10.1016/s0304-4017(99)00199-5] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022]
Abstract
We have investigated the expression of a calcium-binding protein, the S100 protein, in Eimeria brunetti and Eimeria acervulina stages. For this purpose, paraffin sections of distal ileum and bursa of Fabricius or duodenum from experimentally infected chickens were treated with anti-alpha-S100 (anti-alpha subunit of S100 protein) and anti-beta-S100 (anti-beta subunit of S100 protein) monoclonal antibodies and anti-S100 whole molecule polyclonal antibody. The avidin-biotin peroxidase method was used to demonstrate immunoreactivity. In the ileum, our results reveal a positive immunoreaction for the beta subunit and S100 whole molecule within the macrogametes of E. brunetti, whereas they were devoid of immunostaining after treatment of the paraffin sections with the anti-alpha-S100 antiserum. Schizonts and oocysts of E. brunetti and all the E. acervulina stages gave a negative reaction after treatment with any of the three antiserum used in the study. This result indicated that the S100 protein molecules within these stages were not recognized by the antibodies, suggesting that these molecules are different from those identified in macrogametes of E. brunetti. By contrast, in the epithelial cells, lining the lumen of the bursa of Fabricius, macrogametes of E. brunetti were stained by the three antibodies used. These results may indicate the existence of metabolic adaptations that enable the parasite to invade tissue sites different from those where the parasite usually develops.
Collapse
Affiliation(s)
- F López-Bernad
- Department of Animal Pathology, Faculty of Veterinary Sciences, University of Zaragoza, Spain
| | | | | | | | | |
Collapse
|
18
|
Shaw MK. Theileria parva: sporozoite entry into bovine lymphocytes is not dependent on the parasite cytoskeleton. Exp Parasitol 1999; 92:24-31. [PMID: 10329362 DOI: 10.1006/expr.1998.4393] [Citation(s) in RCA: 15] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022]
Abstract
The main conclusion from the present study is that T. parva sporozoite entry is dependent on a functional host cell actin cytoskeleton and is not driven by the parasite. Treating lymphocytes with cytochalasin D resulted in a dose-dependent reduction in the levels of host cell infection. However, the primary effect was to block sporozoite binding and only at the highest concentration (20 microM) was sporozoite internalization significantly reduced. In fact at lower concentrations (1-10 microM) cytochalasin treatment lead to a relative increase in sporozoite internalization. The results are consistent with sporozoite entry being primarily a passive process and with a functional host cell actin cytoskeleton that is required only to maintain the molecular integrity of the surface membrane. Thus T. parva sporozoite entry differs from the process in other apicomplexans, although the results are consistent with a number of features of sporozoite biology. Treatment of lymphocytes with either the microtubule-destabilizing agent, nocodazole, or taxol, which induces microtubule polymerization, had no significant effect on sporozoite binding or entry. As both reagents had the expected effects on the lymphocyte microtubule system, it is unlikely that host cell microtubules are essential for successful sporozoite invasion or establishment.
Collapse
|
19
|
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.
Collapse
Affiliation(s)
- A Bell
- Department of Microbiology, Moyne Institute, Trinity College, Dublin 2, Ireland
| |
Collapse
|
20
|
Lingelbach K, Joiner KA. The parasitophorous vacuole membrane surrounding Plasmodium and Toxoplasma: an unusual compartment in infected cells. J Cell Sci 1998; 111 ( Pt 11):1467-75. [PMID: 9580555 DOI: 10.1242/jcs.111.11.1467] [Citation(s) in RCA: 198] [Impact Index Per Article: 7.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022] Open
Abstract
Plasmodium and Toxoplasma belong to a group of unicellular parasites which actively penetrate their respective mammalian host cells. During the process of invasion, they initiate the formation of a membrane, the so-called parasitophorous vacuolar membrane, which surrounds the intracellular parasite and which differs substantially from endosomal membranes or the membrane of phagolysosomes. The biogenesis and the maintenance of the vacuolar membrane are closely related to the peculiar cellular organization of these parasites and are unique phenomena in cell biology. Here we compare biological similarities and differences between the two parasites, with respect to: (i) the formation, (ii) the maintenance, and (iii) the biological role of the vacuolar membrane. We conclude that most differences between the organisms primarily reflect the different biosynthetic capacities of the host cells they invade.
Collapse
Affiliation(s)
- K Lingelbach
- FB Biology/Zoology, Philipps-University Marburg, Germany
| | | |
Collapse
|
21
|
Affiliation(s)
- M Hommel
- Liverpool School of Tropical Medicine, Liverpool, UK L3 5QA
| | | |
Collapse
|
22
|
Fowler RE, Fookes RE, Mitchell GH, Bannister LH. Malaria, Microtubules and Merozoite Invasion: Reply. ACTA ACUST UNITED AC 1998; 14:41. [PMID: 17040691 DOI: 10.1016/s0169-4758(97)01172-1] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/24/2022]
Affiliation(s)
- R E Fowler
- Malaria Laboratory, Department of Immunology, The Medical School, Guy's Hospital, London, UK SE1 9RT
| | | | | | | |
Collapse
|