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Krishnan D, Pandey M, Nayak S, Ghosh SK. Novel Insights into the Wattle and Daub Model of Entamoeba Cyst Wall Formation and the Importance of Actin Cytoskeleton. Pathogens 2023; 13:20. [PMID: 38251328 PMCID: PMC10818507 DOI: 10.3390/pathogens13010020] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/16/2023] [Revised: 12/12/2023] [Accepted: 12/20/2023] [Indexed: 01/23/2024] Open
Abstract
The "Wattle and Daub" model of cyst wall formation in Entamoeba invadens has been used to explain encystment in Entamoeba histolytica, the causal agent of amoebiasis, and this process could be a potential target for new antiamoebic drugs. In this study, we studied the morphological stages of chitin wall formation in E. invadens in more detail using fluorescent chitin-binding dyes and the immunolocalization of cyst wall proteins. It was found that chitin deposition was mainly initiated on the cell surface at a specific point or at different points at the same time. The cystic wall grew outward and gradually covered the entire surface of the cyst over time, following the model of Wattle and Daub. The onset of chitin deposition was guided by the localization of chitin synthase 1 to the plasma membrane, occurring on the basis of the Jacob lectin in the cell membrane. During encystation, F-actin was reorganized into the cortical region within the early stages of encystation and remained intact until the completion of the chitin wall. The disruption of actin polymerization in the cortical region inhibited proper wall formation, producing wall-less cysts or cysts with defective chitin walls, indicating the importance of the cortical actin cytoskeleton for proper cyst wall formation.
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Affiliation(s)
| | | | | | - Sudip K. Ghosh
- Department of Bioscience and Biotechnology, Indian Institute of Technology Kharagpur, Kharagpur 721302, West Bengal, India; (D.K.); (M.P.); (S.N.)
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Hazra S, Kalyan Dinda S, Kumar Mondal N, Hossain SR, Datta P, Yasmin Mondal A, Malakar P, Manna D. Giant cells: multiple cells unite to survive. Front Cell Infect Microbiol 2023; 13:1220589. [PMID: 37790914 PMCID: PMC10543420 DOI: 10.3389/fcimb.2023.1220589] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/10/2023] [Accepted: 07/26/2023] [Indexed: 10/05/2023] Open
Abstract
Multinucleated Giant Cells (MGCs) are specialized cells that develop from the fusion of multiple cells, and their presence is commonly observed in human cells during various infections. However, MGC formation is not restricted to infections alone but can also occur through different mechanisms, such as endoreplication and abortive cell cycle. These processes lead to the formation of polyploid cells, eventually resulting in the formation of MGCs. In Entamoeba, a protozoan parasite that causes amoebic dysentery and liver abscesses in humans, the formation of MGCs is a unique phenomenon and not been reported in any other protozoa. This organism is exposed to various hostile environmental conditions, including changes in temperature, pH, and nutrient availability, which can lead to stress and damage to its cells. The formation of MGCs in Entamoeba is thought to be a survival strategy to cope with these adverse conditions. This organism forms MGCs through cell aggregation and fusion in response to osmotic and heat stress. The MGCs in Entamoeba are thought to have increased resistance to various stresses and can survive longer than normal cells under adverse conditions. This increased survival could be due to the presence of multiple nuclei, which could provide redundancy in case of DNA damage or mutations. Additionally, MGCs may play a role in the virulence of Entamoeba as they are found in the inflammatory foci of amoebic liver abscesses and other infections caused by Entamoeba. The presence of MGCs in these infections suggests that they may contribute to the pathogenesis of the disease. Overall, this article offers valuable insights into the intriguing phenomenon of MGC formation in Entamoeba. By unraveling the mechanisms behind this process and examining its implications, researchers can gain a deeper understanding of the complex biology of Entamoeba and potentially identify new targets for therapeutic interventions. The study of MGCs in Entamoeba serves as a gateway to exploring the broader field of cell fusion in various organisms, providing a foundation for future investigations into related cellular processes and their significance in health and disease.
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Affiliation(s)
- Shreyasee Hazra
- Department of Biomedical Science and Technology, School of Biological Sciences, Ramakrishna Mission Vivekananda Educational and Research Institute (RKMVERI), Kolkata, India
| | - Suman Kalyan Dinda
- Department of Biomedical Science and Technology, School of Biological Sciences, Ramakrishna Mission Vivekananda Educational and Research Institute (RKMVERI), Kolkata, India
| | - Naba Kumar Mondal
- Department of Biomedical Science and Technology, School of Biological Sciences, Ramakrishna Mission Vivekananda Educational and Research Institute (RKMVERI), Kolkata, India
| | - Sk Rajjack Hossain
- Department of Biomedical Science and Technology, School of Biological Sciences, Ramakrishna Mission Vivekananda Educational and Research Institute (RKMVERI), Kolkata, India
| | - Pratyay Datta
- Department of Biomedical Science and Technology, School of Biological Sciences, Ramakrishna Mission Vivekananda Educational and Research Institute (RKMVERI), Kolkata, India
| | - Afsana Yasmin Mondal
- Institute of Health Sciences, Presidency University, Kolkata, West Bengal, India
| | - Pushkar Malakar
- Department of Biomedical Science and Technology, School of Biological Sciences, Ramakrishna Mission Vivekananda Educational and Research Institute (RKMVERI), Kolkata, India
| | - Dipak Manna
- Department of Biomedical Science and Technology, School of Biological Sciences, Ramakrishna Mission Vivekananda Educational and Research Institute (RKMVERI), Kolkata, India
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Balbhim SS, Sarkar S, Vasudevan M, Ghosh SK. Three-amino acid loop extension homeodomain proteins regulate stress responses and encystation in Entamoeba. Mol Microbiol 2023. [PMID: 37424153 DOI: 10.1111/mmi.15121] [Citation(s) in RCA: 2] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/24/2022] [Revised: 06/22/2023] [Accepted: 06/26/2023] [Indexed: 07/11/2023]
Abstract
It is interesting to identify factors involved in the regulation of the encystation of Entamoeba histolytica that differentiate trophozoites into cysts. Evolutionarily conserved three amino acid loop extension (TALE) homeodomain proteins act as transcription factors and execute a variety of functions that are essential for life. A TALE homeodomain (EhHbox) protein-encoding gene has been identified in E. histolytica (Eh) that is highly upregulated during heat shock, glucose, and serum starvation. Its ortholog, EiHbox1, a putative homeobox protein in E. invadens (Ei), is also highly upregulated during the early hours of encystation, glucose starvation, and heat shock. They belong to the PBX family of TALE homeobox proteins and have conserved residues in the homeodomain that are essential for DNA binding. Both are localized in the nucleus during encystation and under different stress conditions. The electrophoretic mobility shift assay confirmed that the recombinant GST-EhHbox binds to the reported TGACAG and TGATTGAT motifs. Down-regulation of EiHbox1 by gene silencing reduced Chitin synthase, Jacob, and increased Jessie gene expression, resulting in defective cysts and decreased encystation efficiency and viability. Overall, our results suggest that the TALE homeobox family has been conserved during evolution and acts as a transcription factor to control the differentiation of Entamoeba by regulating the key encystation-induced genes.
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Affiliation(s)
- Sonar Shubham Balbhim
- Department of Biotechnology, Indian Institute of Technology Kharagpur, Kharagpur, India
| | - Shilpa Sarkar
- Department of Biotechnology, Indian Institute of Technology Kharagpur, Kharagpur, India
| | | | - Sudip K Ghosh
- Department of Biotechnology, Indian Institute of Technology Kharagpur, Kharagpur, India
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Wesel J, Ingram-Smith C. Glycogen Metabolism and Its Role in Growth and Encystation in Entamoeba histolytica. Life (Basel) 2023; 13:1529. [PMID: 37511904 PMCID: PMC10381564 DOI: 10.3390/life13071529] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/25/2023] [Revised: 07/03/2023] [Accepted: 07/06/2023] [Indexed: 07/30/2023] Open
Abstract
Entamoeba histolytica is a parasitic protozoan that causes diarrheal disease in approximately 100 million people worldwide every year. E. histolytica has two forms, the growing trophozoite and the infectious cyst. Trophozoites colonizing the large intestine form cysts that are released into the environment. The ingestion of the cysts in contaminated food and water continues the disease cycle. Here, we investigated the role of glycogen in trophozoite growth and encystation. Glycogen is thought to provide precursors for the synthesis of chitin, a major component of the protective cyst wall. We propose that glycogen also serves as an energy source during metabolic adaptation to different nutrient environments. We examined the role of glycogen in E. histolytica by analyzing the growth and encystation of RNAi strains with reduced expression of the single gene-encoding glycogen synthase (GYS) or two of three genes encoding glycogen phosphorylase (PYG). The GYS RNAi strain had a greatly reduced glycogen accumulation, and both the GYS and PYG RNAi strains exhibited reduced growth in the glucose-poor medium. Both RNAi strains also showed reduced cyst production. Our results suggest glycogen synthesis and degradation are vital to the growth and adaptation of E. histolytica to a low-glucose environment such as that encountered in the large intestine.
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Affiliation(s)
- Jordan Wesel
- Department of Genetics and Biochemistry, Clemson University, Clemson, SC 29634, USA
- Eukaryotic Pathogens Innovation Center, Clemson University, Clemson, SC 29634, USA
| | - Cheryl Ingram-Smith
- Department of Genetics and Biochemistry, Clemson University, Clemson, SC 29634, USA
- Eukaryotic Pathogens Innovation Center, Clemson University, Clemson, SC 29634, USA
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Becker C, Adam A, Dommisch H, Stach T, Schaefer AS. In vitro induction of Entamoeba gingivalis cyst-like structures from trophozoites in response to antibiotic treatment. Front Cell Infect Microbiol 2023; 13:1201394. [PMID: 37469604 PMCID: PMC10352839 DOI: 10.3389/fcimb.2023.1201394] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Grants] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/06/2023] [Accepted: 06/16/2023] [Indexed: 07/21/2023] Open
Abstract
Background Entamoeba gingivalis (E. gingivalis) is an anaerobic protozoan that is strongly associated with inflamed periodontal pockets. It is able to invade the mucosal epithelium of the human host, where it can feed on epithelial cells and elicit a severe innate immune response. Unlike other Entamoeba species, it is considered that E. gingivalis cannot form cysts, because it is a non-infectious protozoan. The lack of encystation capability would make it susceptible to periodontal treatment. However, it is not clear how the human host becomes infected with E. gingivalis trophozoites. We investigated the ability of E. gingivalis to encapsulate in response to an unfavorable environment in vitro. Methods Different strains of E. gingivalis, isolated from inflamed periodontal pocket samples, were cultured for 8 days in the presence or absence of the antimicrobials amoxycillin and metronidazole. To reveal cyst formation, we investigated the morphology and ultrastructure of the amoeba by light, fluorescence, transmission and scanning electron microscopy. We also used the fluorescent dye calcofluor white M2R to demonstrate chitin present in the cyst wall. Results We observed exocysts and an intra-cystic space separating the encapsulated trophozoite from the environment. Remarkably, cysts showed a smooth surface, polygonal edges and smaller size compared to free-living trophozoites. In addition, encapsulated trophozoites that detached from the cyst wall had a dense cytoplasma without phagocytic vesicles. The cyst walls consisted of chitin as in other Entamoba species. The encapsulated trophozoids were mononuclear after antibioticinduced encapsulation. Discussion We conclude that E. gingivalis cyst formation has significant implications for dissemination and infection and may explain why established treatment approaches often fail to halt periodontal tissue destruction during periodontitis and peri-implantitis.
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Affiliation(s)
- Christin Becker
- Molecular Genetics of Oral Inflammatory Diseases Group, Institute for Dental and Craniofacial Sciences, Department of Periodontology, Oral Medicine and Oral Surgery, Charité – University Medicine Berlin, Corporate Member of Freie Universität Berlin, Humboldt-Universität zu Berlin, and Berlin Institute of Health, Berlin, Germany
| | - Aysegül Adam
- Molecular Genetics of Oral Inflammatory Diseases Group, Institute for Dental and Craniofacial Sciences, Department of Periodontology, Oral Medicine and Oral Surgery, Charité – University Medicine Berlin, Corporate Member of Freie Universität Berlin, Humboldt-Universität zu Berlin, and Berlin Institute of Health, Berlin, Germany
| | - Henrik Dommisch
- Molecular Genetics of Oral Inflammatory Diseases Group, Institute for Dental and Craniofacial Sciences, Department of Periodontology, Oral Medicine and Oral Surgery, Charité – University Medicine Berlin, Corporate Member of Freie Universität Berlin, Humboldt-Universität zu Berlin, and Berlin Institute of Health, Berlin, Germany
| | - Thomas Stach
- Department of Molecular Parasitology, Institute of Biology, Humboldt-Universität zu Berlin, Berlin, Germany
| | - Arne S. Schaefer
- Molecular Genetics of Oral Inflammatory Diseases Group, Institute for Dental and Craniofacial Sciences, Department of Periodontology, Oral Medicine and Oral Surgery, Charité – University Medicine Berlin, Corporate Member of Freie Universität Berlin, Humboldt-Universität zu Berlin, and Berlin Institute of Health, Berlin, Germany
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Bhattacharya S. Episomal and chromosomal DNA replication and recombination in Entamoeba histolytica. Front Mol Biosci 2023; 10:1212082. [PMID: 37363402 PMCID: PMC10285105 DOI: 10.3389/fmolb.2023.1212082] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/25/2023] [Accepted: 05/26/2023] [Indexed: 06/28/2023] Open
Abstract
Entamoeba histolytica is the causative agent of amoebiasis. DNA replication studies in E. histolytica first started with the ribosomal RNA genes located on episomal circles. Unlike most plasmids, Entamoeba histolytica rDNA circles lacked a fixed origin. Replication initiated from multiple sites on the episome, and these were preferentially used under different growth conditions. In synchronized cells the early origins mapped within the rDNA transcription unit, while at later times an origin in the promoter-proximal upstream intergenic spacer was activated. This is reminiscent of eukaryotic chromosomal replication where multiple potential origins are used. Biochemical studies on replication and recombination proteins in Entamoeba histolytica picked up momentum once the genome sequence was available. Sequence search revealed homologs of DNA replication and recombination proteins, including meiotic genes. The replicative DNA polymerases identified included the α, δ, ε of polymerase family B; lesion repair polymerases Rev1 and Rev3; a translesion repair polymerase of family A, and five families of polymerases related to family B2. Biochemical analysis of EhDNApolA confirmed its polymerase activity with expected kinetic constants. It could perform strand displacement, and translesion synthesis. The purified EhDNApolB2 had polymerase and exonuclease activities, and could efficiently bypass some types of DNA lesions. The single DNA ligase (EhDNAligI) was similar to eukaryotic DNA ligase I. It was a high-fidelity DNA ligase, likely involved in both replication and repair. Its interaction with EhPCNA was also demonstrated. The recombination-related proteins biochemically characterized were EhRad51 and EhDmc1. Both shared the canonical properties of a recombinase and could catalyse strand exchange over long DNA stretches. Presence of Dmc1 indicates the likelihood of meiosis in this parasite. Direct evidence of recombination in Entamoeba histolytica was provided by use of inverted repeat sequences located on plasmids or chromosomes. In response to a variety of stress conditions, and during encystation in Entamoeba invadens, recombination-related genes were upregulated and homologous recombination was enhanced. These data suggest that homologous recombination could have critical roles in trophozoite growth and stage conversion. Availability of biochemically characterized replication and recombination proteins is an important resource for exploration of novel anti-amoebic drug targets.
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de Obeso Fernández Del Valle A, Scheckhuber CQ, Chavaro-Pérez DA, Ortega-Barragán E, Maciver SK. mRNA Sequencing Reveals Upregulation of Glutathione S-Transferase Genes during Acanthamoeba Encystation. Microorganisms 2023; 11:992. [PMID: 37110414 PMCID: PMC10142586 DOI: 10.3390/microorganisms11040992] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/22/2023] [Revised: 04/04/2023] [Accepted: 04/05/2023] [Indexed: 04/29/2023] Open
Abstract
Some members of the genus Acanthamoeba are facultative pathogens typically with a biphasic lifestyle: trophozoites and cysts. Acanthamoeba is capable of infecting the cornea, resulting in Acanthamoeba keratitis. The cyst is one of the key components for the persistence of infection. Gene expression during Acanthamoeba encystation showed an upregulation of glutathione S-transferase (GST) genes and other closely related proteins. mRNA sequencing showed GST, and five genes with similar sequences were upregulated after 24 h of inducing encystation. GST overexpression was verified with qPCR using the HPRT and the cyst-specific protein 21 genes as controls. The GST inhibitor ethacrynic acid was found to decrease cell viability by 70%. These results indicate a role of GST in successful encystation, possibly by maintaining redox balance. GST and associated processes could be targets for potential treatments alongside regular therapies to reduce relapses of Acanthamoeba infection.
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Affiliation(s)
- Alvaro de Obeso Fernández Del Valle
- Departamento de Bioingeniería, Escuela de Ingeniería y Ciencias, Tecnologico de Monterrey, Ave. Eugenio Garza Sada 2501, Monterrey 64849, Nuevo León, Mexico
| | - Christian Quintus Scheckhuber
- Departamento de Bioingeniería, Escuela de Ingeniería y Ciencias, Tecnologico de Monterrey, Ave. Eugenio Garza Sada 2501, Monterrey 64849, Nuevo León, Mexico
| | - David Armando Chavaro-Pérez
- Tecnologico de Monterrey, Escuela de Medicina y Ciencias de la Salud, Ave. Eugenio Garza Sada 2501, Monterrey 64849, Nuevo León, Mexico
| | - Erandi Ortega-Barragán
- Departamento de Bioingeniería, Escuela de Ingeniería y Ciencias, Tecnologico de Monterrey, Ave. Eugenio Garza Sada 2501, Monterrey 64849, Nuevo León, Mexico
| | - Sutherland K Maciver
- Centre for Discovery Brain Sciences, Edinburgh Medical School, Biomedical Sciences, University of Edinburgh, Hugh Robson Building, George Square, Edinburgh EH8 9XD, Scotland, UK
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Sharma M, Zhang H, Ehrenkaufer G, Singh U. Stress Response in Entamoeba histolytica Is Associated with Robust Processing of tRNA to tRNA Halves. mBio 2023;:e0345022. [PMID: 36809068 DOI: 10.1128/mbio.03450-22] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/23/2023] Open
Abstract
tRNA-derived fragments have been reported in many different organisms and have diverse cellular roles, such as regulating gene expression, inhibiting protein translation, silencing transposable elements, and modulating cell proliferation. In particular, tRNA halves, a class of tRNA fragments produced by the cleavage of tRNAs in the anti-codon loop, have been widely reported to accumulate under stress and regulate translation in cells. Here, we report the presence of tRNA-derived fragments in Entamoeba, with tRNA halves being the most abundant. We further established that tRNA halves accumulate in the parasites upon different stress stimuli such as oxidative stress, heat shock, and serum starvation. We also observed differential expression of tRNA halves during developmental changes of trophozoite-to-cyst conversion, with various tRNA halves accumulating during early encystation. In contrast to other systems, the stress response does not appear to be mediated by a few specific tRNA halves, as multiple tRNAs appear to be processed during the various stresses. Furthermore, we identified some tRNA-derived fragments associated with Entamoeba Argonaute proteins, EhAgo2-2 and EhAgo2-3, which have a preference for different tRNA-derived fragment species. Finally, we show that tRNA halves are packaged inside extracellular vesicles secreted by amoebas. The ubiquitous presence of tRNA-derived fragments, their association with the Argonaute proteins, and the accumulation of tRNA halves during multiple different stresses, including encystation, suggest a nuanced level of gene expression regulation mediated by different tRNA-derived fragments in Entamoeba. IMPORTANCE In the present study, we report for the first time the presence of tRNA-derived fragments in Entamoeba. tRNA-derived fragments were identified by bioinformatics analyses of small-RNA sequencing data sets from the parasites and also confirmed experimentally. We found that tRNA halves accumulated in parasites exposed to environmental stress or during the developmental process of encystation. We also found that shorter tRNA-derived fragments are bound to Entamoeba Argonaute proteins, indicating that they may have a potential role in the Argonaute-mediated RNA-interference pathway, which mediates robust gene silencing in Entamoeba. We noticed that in response to heat shock, the protein translation levels were elevated in the parasites. This effect was reversed in the presence of an analog of leucine, which also reduced the levels of the tRNA halves in the stressed cells. Our results suggest that tRNA-derived fragments in Entamoeba have a possible role in regulating gene expression during environmental stress.
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Akbar N, El-Gamal MI, Zaraei SO, Saeed BQ, Khan NA, Siddiqui R. Anti-amoebic activity of a series of benzofuran/benzothiophene derivatives against Acanthamoeba castellanii belonging to the T4 genotype. J Appl Microbiol 2023; 134:6947815. [PMID: 36626774 DOI: 10.1093/jambio/lxac030] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/01/2022] [Revised: 10/11/2022] [Accepted: 10/20/2022] [Indexed: 01/12/2023]
Abstract
AIMS To determine the anti-amoebic activity of benzofuran/benzothiophene-possessing compounds against Acanthamoeba castellanii of the T4 genotype. METHOD AND RESULTS A series of benzofuran/benzothiophene-possessing compounds were tested for their anti-amoebic activities, in particular, to block encystation and excystation processes in amoebae. Cytotoxicity of the compounds were evaluated using lactate dehydrogenase (LDH) assays. The amoebicidal assay results revealed significant anti-amoebic effects against A. castellanii. Compounds 1p and 1e showed the highest amoebicidal activity, eliminating 68% and 64% of the amoebae, respectively. These compounds remarkably repressed both the encystation and excystation processes in A. castellanii. Furthermore, the selected compounds presented minimal cytotoxic properties against human cells, as well as considerably abridged amoeba-mediated cytopathogenicity when compared to the amoebae alone. CONCLUSIONS Our findings show that benzofuran/benzothiophene derivatives depict potent anti-amoebic activities; thus these compounds should be used as promising and novel agents in the rationale development of therapeutic strategies against Acanthamoeba infections.
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Affiliation(s)
- Noor Akbar
- College of Arts and Sciences, American University of Sharjah, University City, Sharjah 26666, United Arab Emirates.,Sharjah Institute for Medical Research, University of Sharjah, Sharjah 27272, Unites Arab Emirates
| | - Mohammed I El-Gamal
- Sharjah Institute for Medical Research, University of Sharjah, Sharjah 27272, United Arab Emirates.,Department of Medicinal Chemistry, College of Pharmacy, University of Sharjah, Sharjah 27272, United Arab Emirates.,Department of Medicinal Chemistry, Faculty of Pharmacy, Mansoura University, Mansoura 35516, Egypt
| | - Seyed-Omar Zaraei
- Sharjah Institute for Medical Research, University of Sharjah, Sharjah 27272, United Arab Emirates
| | - Balsam Qubais Saeed
- Sharjah Institute for Medical Research, University of Sharjah, Sharjah 27272, United Arab Emirates.,Department of Clinical Sciences, College of Medicine, University of Sharjah, Sharjah 27272, United Arab Emirates
| | - Naveed Ahmed Khan
- Sharjah Institute for Medical Research, University of Sharjah, Sharjah 27272, United Arab Emirates.,Department of Medical Biology, Faculty of Medicine, Istinye University, Istanbul, 34010, Turkey
| | - Ruqaiyyah Siddiqui
- College of Arts and Sciences, American University of Sharjah, University City, Sharjah 26666, United Arab Emirates.,Department of Medical Biology, Faculty of Medicine, Istinye University, Istanbul, 34010, Turkey
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Du Q, Schaap P. Autophagy of the somatic stalk cells likely nurses the propagating spores of Dictyostelid social amoebas. Open Res Eur 2022; 2:104. [PMID: 36860212 PMCID: PMC7614253 DOI: 10.12688/openreseurope.14947.2] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Accepted: 11/14/2022] [Indexed: 11/24/2022]
Abstract
Background: Autophagy (self-feeding) assists survival of starving cells by partial self-digestion, while dormancy as cysts, spores or seeds enables long-term survival. Starving Dictyostelium amoebas construct multicellular fruiting bodies with spores and stalk cells, with many Dictyostelia still able to encyst individually like their single-celled ancestors. While autophagy mostly occurs in the somatic stalk cells, autophagy gene knock-outs in Dictyostelium discoideum ( D. discoideum) formed no spores and lacked cAMP induction of prespore gene expression. Methods: To investigate whether autophagy also prevents encystation, we knocked-out autophagy genes atg5 and atg7 in the dictyostelid Polysphondylium pallidum, which forms both spores and cysts. We measured spore and cyst differentiation and viability in the knock-out as well as stalk and spore gene expression and its regulation by cAMP. We tested a hypothesis that spores require materials derived from autophagy in stalk cells. Sporulation requires secreted cAMP acting on receptors and intracellular cAMP acting on PKA. We compared the morphology and viability of spores developed in fruiting bodies with spores induced from single cells by stimulation with cAMP and 8Br-cAMP, a membrane-permeant PKA agonist. Results: Loss of autophagy in P. pallidum reduced but did not prevent encystation. Stalk cells still differentiated but stalks were disorganised. However, no spores were formed at all and cAMP-induced prespore gene expression was lost. D. discoideum spores induced in vitro by cAMP and 8Br-cAMP were smaller and rounder than spores formed multicellularly and while they were not lysed by detergent they germinated not (strain Ax2) or poorly (strain NC4), unlike spores formed in fruiting bodies. Conclusions: The stringent requirement of sporulation on both multicellularity and autophagy, which occurs mostly in stalk cells, suggests that stalk cells nurse the spores through autophagy. This highlights autophagy as a major cause for somatic cell evolution in early multicellularity.
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Affiliation(s)
- Qingyou Du
- School of Life Sciences, University of Dundee, Dundee, Angus, DD15EH, UK
| | - Pauline Schaap
- School of Life Sciences, University of Dundee, Dundee, Angus, DD15EH, UK
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Nyonda MA, Kloehn J, Sosnowski P, Krishnan A, Lentini G, Maco B, Marq JB, Hannich JT, Hopfgartner G, Soldati-Favre D. Ceramide biosynthesis is critical for establishment of the intracellular niche of Toxoplasma gondii. Cell Rep 2022; 40:111224. [PMID: 35977499 PMCID: PMC9396527 DOI: 10.1016/j.celrep.2022.111224] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/23/2021] [Revised: 06/06/2022] [Accepted: 07/26/2022] [Indexed: 11/15/2022] Open
Abstract
Toxoplasma gondii possesses sphingolipid synthesis capabilities and is equipped to salvage lipids from its host. The contribution of these two routes of lipid acquisition during parasite development is unclear. As part of a complete ceramide synthesis pathway, T. gondii expresses two serine palmitoyltransferases (TgSPT1 and TgSPT2) and a dihydroceramide desaturase. After deletion of these genes, we determine their role in parasite development in vitro and in vivo during acute and chronic infection. Detailed phenotyping through lipidomic approaches reveal a perturbed sphingolipidome in these mutants, characterized by a drastic reduction in ceramides and ceramide phosphoethanolamines but not sphingomyelins. Critically, parasites lacking TgSPT1 display decreased fitness, marked by reduced growth rates and a selective defect in rhoptry discharge in the form of secretory vesicles, causing an invasion defect. Disruption of de novo ceramide synthesis modestly affects acute infection in vivo but severely reduces cyst burden in the brain of chronically infected mice. De novo sphingolipid synthesis is active at the ER of Toxoplasma gondii T. gondii scavenges sphingomyelins but synthesizes ceramide phosphoethanolamines TgSPT1 is required for establishment of the intracellular niche during invasion Defects in T. gondii sphingolipid synthesis affect chronic infection in vivo
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Affiliation(s)
- Mary Akinyi Nyonda
- Department of Microbiology and Molecular Medicine, University of Geneva, Geneva, Switzerland
| | - Joachim Kloehn
- Department of Microbiology and Molecular Medicine, University of Geneva, Geneva, Switzerland
| | - Piotr Sosnowski
- Life Sciences Mass Spectrometry, Department of Inorganic and Analytical Chemistry, University of Geneva, 24 Quai Ernest Ansermet, 1211 Geneva 4, Switzerland
| | - Aarti Krishnan
- Department of Microbiology and Molecular Medicine, University of Geneva, Geneva, Switzerland
| | - Gaëlle Lentini
- Department of Microbiology and Molecular Medicine, University of Geneva, Geneva, Switzerland
| | - Bohumil Maco
- Department of Microbiology and Molecular Medicine, University of Geneva, Geneva, Switzerland
| | - Jean-Baptiste Marq
- Department of Microbiology and Molecular Medicine, University of Geneva, Geneva, Switzerland
| | - J Thomas Hannich
- Department of Biochemistry, NCCR Chemical Biology, University of Geneva, Quai Ernest-Ansermet 30, Geneva, Switzerland
| | - Gerard Hopfgartner
- Life Sciences Mass Spectrometry, Department of Inorganic and Analytical Chemistry, University of Geneva, 24 Quai Ernest Ansermet, 1211 Geneva 4, Switzerland
| | - Dominique Soldati-Favre
- Department of Microbiology and Molecular Medicine, University of Geneva, Geneva, Switzerland.
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12
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Siddiqui R, Makhlouf Z, Akbar N, Khamis M, Ibrahim T, Khan AS, Khan NA. Antiamoebic properties of salicylic acid-based deep eutectic solvents for the development of contact lens disinfecting solutions against Acanthamoeba. Mol Biochem Parasitol 2022; 250:111493. [PMID: 35753525 DOI: 10.1016/j.molbiopara.2022.111493] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/01/2022] [Revised: 05/30/2022] [Accepted: 06/20/2022] [Indexed: 10/17/2022]
Abstract
Acanthamoeba castellanii is a protist pathogen that can cause sight-threatening keratitis and a fatal infection of the central nervous system, known as granulomatous amoebic encephalitis. In this study, effects of five malonic acid and salicylic acid-based deep eutectic solvents (DES) on A. castellanii were investigated. These are salicylic acid-trioctylphosphine (DES 1), salicylic acid- trihexylamine (DES 2), salicylic acid-trioctylamine (DES 3), malonic acid-trioctylphosphine (DES 4) and malonic acid-trihexylamine (DES 5). The experiments were done by performing amoebicidal, encystment, excystment, cytopathogenicity, and cytotoxicity assays. At micromolar dosage, the solvents DES 2 and DES 3 displayed significant amoebicidal effects (P<0.05), inhibited encystment and excystment, undermined the cell-mediated cytopathogenicity of A. castellanii, and also displayed minimal cytotoxicity to human cells. Conversely, the chemical components of these solvents: salicylic acid, trihexylamine, and trioctylamine showed minimal effects when tested individually. These results are very promising and to the best of our knowledge, are reported for the first time on the effects of deep eutectic solvents on amoebae. These results can be applied in the development of new formulations of novel contact lens disinfectants against Acanthamoeba castellanii.
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Affiliation(s)
- Ruqaiyyah Siddiqui
- College of Arts and Sciences, American University of Sharjah, University City, Sharjah 26666, United Arab Emirates
| | - Zinb Makhlouf
- College of Arts and Sciences, American University of Sharjah, University City, Sharjah 26666, United Arab Emirates
| | - Noor Akbar
- College of Arts and Sciences, American University of Sharjah, University City, Sharjah 26666, United Arab Emirates
| | - Mustafa Khamis
- College of Arts and Sciences, American University of Sharjah, University City, Sharjah 26666, United Arab Emirates
| | - Taleb Ibrahim
- Department of Chemical Engineering, College of Engineering, American University of Sharjah, P.O. Box 26666, Sharjah, United Arab Emirates
| | - Amir Sada Khan
- Department of Chemical Engineering, College of Engineering, American University of Sharjah, P.O. Box 26666, Sharjah, United Arab Emirates
| | - Naveed Ahmed Khan
- Department of Clinical Sciences, College of Medicine, University of Sharjah, University, City, Sharjah, 27272, United Arab Emirates.
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13
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Walters HA, Welter BH, Moss HC, Villano MA, Orobio-Hurtado R, Sullivan WJ Jr, Temesvari LA. Eukaryotic Initiation Factor 2α Kinases Regulate Virulence Functions, Stage Conversion, and the Stress Response in Entamoeba invadens. mSphere 2022;:e0013122. [PMID: 35638357 DOI: 10.1128/msphere.00131-22] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/28/2022] Open
Abstract
Entamoeba histolytica is a protozoan parasite that causes amoebic dysentery and liver abscess. This pathogen possesses a two-stage life cycle consisting of an environmentally stable cyst and a pathogenic amoeboid trophozoite. Since infection is acquired by ingestion of cysts from contaminated food and water, this parasite is prevalent in underdeveloped countries. A reptilian pathogen, Entamoeba invadens, which can encyst in culture, has long served as a surrogate to study stage conversion. In the host, Entamoeba species must manage stress, including nutrient deprivation and host immune pressure. In many systems, the stress response is characterized by downregulation of translation, which is initiated by the phosphorylation of eukaryotic initiation factor-2 alpha (eIF2α). In mammalian cells, this phosphorylation is carried out by a family of eIF2α kinases. A canonical eIF2α translational control system exists in Entamoeba species; however, no eIF2α kinases have been characterized. In this study, we identified two eIF2α kinases in E. invadens, EiIF2K-A and EiIF2K-B. Their identity as eIF2α kinases was validated using a heterologous yeast system. We used an RNA interference (RNAi) trigger-mediated silencing system to reduce expression of EiIF2K-A, which also reduced expression of EiIF2K-B. Parasites with decreased kinase expression exhibited decreased phosphorylation of eIF2α and increased sensitivity to oxidative stress. Diminished kinase expression also correlated with an increased rate of encystation, a decreased rate of excystation, and an increase in several virulence functions, erythrophagocytosis and adhesion to host cells. Taken together, these data suggest that EiIF2K-A and EiIF2K-B are authentic eIF2α kinases that may regulate the Entamoeba stress response. IMPORTANCEEntamoeba histolytica is a human pathogen that causes dysentery and affects millions of people worldwide. This parasite possesses a two-stage life cycle: an environmentally stable cyst and the pathogenic trophozoite. Cysts are ingested from contaminated food and water; thus, this parasite in prevalent in underdeveloped countries. Current therapies commonly cause adverse side effects; therefore, new treatments are needed. In the host, Entamoeba experiences stress brought on, in part, by the host immune system. Understanding stage conversion and the stress response of this pathogen may lead to new drug therapies. Using the model organism E. invadens, we identified two kinases similar to those involved in stress and stage conversion in other systems. We determined that these kinases may regulate the oxidative stress response, stage conversion, and virulence. This work is significant, as it will inform future studies on the life cycle and pathogenicity of Entamoeba species.
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14
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Shih HW, Alas GCM, Paredez AR. A cell-cycle-dependent GARP-like transcriptional repressor regulates the initiation of differentiation in Giardia lamblia. Proc Natl Acad Sci U S A 2022; 119:e2204402119. [PMID: 35613049 DOI: 10.1073/pnas.2204402119] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/18/2022] Open
Abstract
SignificanceTransition between life cycle stages is a common feature among parasitic pathogens, and its regulation must be optimized to balance persistence of infection with transmission. The early transcription factors (TFs) regulating commitment to differentiate are totally unknown in Giardia. In this work, we identified Golden2, ARR-B, Psr-1-like protein 1 (GARP)-like protein 4 (GLP4), a previously uncharacterized GARP-like TF, as an early-acting transcriptional repressor that inhibits G1+S cells from entering the encystation pathway. GLP4 is therefore a key regulator controlling the balance between proliferative growth and terminal differentiation into infective cysts.
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15
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Chu KB, Lee HA, Pflieger M, Fischer F, Asfaha Y, Alves Avelar LA, Skerhut A, Kassack MU, Hansen FK, Schöler A, Kurz T, Kim MJ, Moon EK, Quan FS. Antiproliferation and Anti encystation Effect of Class II Histone Deacetylase Inhibitors on Acanthamoeba castellanii. ACS Infect Dis 2022; 8:271-279. [PMID: 34994538 DOI: 10.1021/acsinfecdis.1c00390] [Citation(s) in RCA: 7] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/04/2023]
Abstract
Acanthamoeba is a ubiquitous and free-living protozoan pathogen responsible for causing Acanthamoeba keratitis (AK), a severe corneal infection inflicting immense pain that can result in permanent blindness. A drug-based treatment of AK has remained arduous because Acanthamoeba trophozoites undergo encystment to become highly drug-resistant cysts upon exposure to harsh environmental conditions such as amoebicidal agents (e.g., polyhexanide, chloroquine, and chlorohexidine). As such, drugs that block the Acanthamoeba encystation process could result in a successful AK treatment. Histone deacetylase inhibitors (HDACi) have recently emerged as novel therapeutic options for treating various protozoan and parasitic diseases. Here, we investigated whether novel HDACi suppress the proliferation and encystation of Acanthamoeba. Synthetic class II HDACi FFK29 (IIa selective) and MPK576 (IIb selective) dose-dependently decreased the viability of Acanthamoeba trophozoites. While these HDACi demonstrated a negligible effect on the viability of mature cysts, Acanthamoeba encystation was significantly inhibited by these HDACi. Apoptosis was slightly increased in trophozoites after a treatment with these HDACi, whereas cysts were unaffected by the HDACi exposure. The viability of human corneal cells was not affected by HDACi concentrations up to 10 μmol/L. In conclusion, these synthetic HDACi demonstrated potent amoebicidal effects and inhibited the growth and encystation of Acanthamoeba, thus highlighting their enormous potential for further development.
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Affiliation(s)
- Ki-Back Chu
- Department of Biomedical Science, Graduate School, Kyung Hee University, 02447 Seoul, South Korea
| | - Hae-Ahm Lee
- Medical Research Center for Bioreaction to Reactive Oxygen Species and Biomedical Science Institute, School of Medicine, Kyung Hee University, 02447 Seoul, South Korea
| | - Marc Pflieger
- Institute of Pharmaceutical and Medicinal Chemistry, Heinrich Heine University, 40225 Dusseldorf, Germany
| | - Fabian Fischer
- Institute of Pharmaceutical and Medicinal Chemistry, Heinrich Heine University, 40225 Dusseldorf, Germany
| | - Yodita Asfaha
- Institute of Pharmaceutical and Medicinal Chemistry, Heinrich Heine University, 40225 Dusseldorf, Germany
| | - Leandro A. Alves Avelar
- Institute of Pharmaceutical and Medicinal Chemistry, Heinrich Heine University, 40225 Dusseldorf, Germany
| | - Alexander Skerhut
- Institute of Pharmaceutical and Medicinal Chemistry, Heinrich Heine University, 40225 Dusseldorf, Germany
| | - Matthias U. Kassack
- Institute of Pharmaceutical and Medicinal Chemistry, Heinrich Heine University, 40225 Dusseldorf, Germany
| | - Finn K Hansen
- Pharmaceutical and Cell Biological Chemistry, Pharmaceutical Institute, University of Bonn, An der Immenburg 4, 53121 Bonn, Germany
| | - Andrea Schöler
- Institute for Drug Discovery, Medical Faculty, Leipzig University, Brüderstraße 34, 04103 Leipzig, Germany
| | - Thomas Kurz
- Institute of Pharmaceutical and Medicinal Chemistry, Heinrich Heine University, 40225 Dusseldorf, Germany
| | - Min-Jeong Kim
- Medical Research Center for Bioreaction to Reactive Oxygen Species and Biomedical Science Institute, School of Medicine, Kyung Hee University, 02447 Seoul, South Korea
| | - Eun-Kyung Moon
- Department of Medical Zoology, Kyung Hee University, School of Medicine, 02447 Seoul, South Korea
| | - Fu-Shi Quan
- Medical Research Center for Bioreaction to Reactive Oxygen Species and Biomedical Science Institute, School of Medicine, Kyung Hee University, 02447 Seoul, South Korea
- Department of Medical Zoology, Kyung Hee University, School of Medicine, 02447 Seoul, South Korea
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16
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Sama-ae I, Sangkanu S, Siyadatpanah A, Norouzi R, Chuprom J, Mitsuwan W, Surinkaew S, Boonhok R, Paul AK, Mahboob T, Abtahi NS, Jimoh TO, Oliveira SM, Gupta M, Sin C, de Lourdes Pereira M, Wilairatana P, Wiart C, Rahmatullah M, Dolma KG, Nissapatorn V. Targeting Acanthamoeba proteins interaction with flavonoids of Propolis extract by in vitro and in silico studies for promising therapeutic effects. F1000Res 2022; 11:1274. [PMID: 36936052 PMCID: PMC10015121 DOI: 10.12688/f1000research.126227.1] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Accepted: 10/25/2022] [Indexed: 11/09/2022] Open
Abstract
Background : Propolis is a natural resinous mixture produced by bees. It provides beneficial effects on human health in the treatment/management of many diseases. The present study was performed to demonstrate the anti- Acanthamoeba activity of ethanolic extracts of Propolis samples from Iran. The interactions of the compounds and essential proteins of Acanthamoeba were also visualized through docking simulation. Methods: The minimal inhibitory concentrations (MICs) of Propolis extract against Acanthamoeba trophozoites and cysts was determined in vitro. In addition, two-fold dilutions of each of the agents were tested for encystment, excystment and adhesion inhibitions. Three major compounds of Propolis extract such as chrysin, tectochrysin and pinocembrin have been selected in molecular docking approach to predict the compounds that might be responsible for encystment, excystment and adhesion inhibitions of A. castellanii. Furthermore, to confirm the docking results, molecular dynamics (MD) simulations were also carried out for the most promising two ligand-pocket complexes from docking studies. Results : The minimal inhibitory concentrations (MICs) 62.5 and 125 µg/mL of the most active Propolis extract were assessed in trophozoites stage of Acanthamoeba castellanii ATCC30010 and ATCC50739, respectively. At concentrations lower than their MICs values (1/16 MIC), Propolis extract revealed inhibition of encystation. However, at 1/2 MIC, it showed a potential inhibition of excystation and anti-adhesion. The molecular docking and dynamic simulation revealed the potential capability of Pinocembrin to form hydrogen bonds with A. castellanii Sir2 family protein (AcSir2), an encystation protein of high relevance for this process in Acanthamoeba. Conclusions : The results obtained provided a candidate for the development of therapeutic drugs against Acanthamoeba infection. In vivo experiments and clinical trials are necessary to support this claim.
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Affiliation(s)
- Imran Sama-ae
- Department of Medical Technology, School of Allied Health Sciences and Center of Excellence Research for Melioidosis and Microorganisms (CERMM), Walailak University, Nakhon Si Thammarat, Thailand
| | - Suthinee Sangkanu
- School of Allied Health Sciences, Southeast Asia Water Team (SEA Water Team) and World Union for Herbal Drug Discovery (WUHeDD), Walailak University, Nakhon Si Thammarat, Thailand
| | - Abolghasem Siyadatpanah
- Ferdows School of Paramedical and Health, Birjand University of Medical Sciences, Birjand, Iran
- Department of Microbiology, School of Medicine, Infectious Diseases Research Center, Gonabad University of Medical Sciences, Gonabad, Iran
| | - Roghayeh Norouzi
- Department of Pathobiology, Faculty of Veterinary Medicine, University of Tabriz, Tabriz, Iran
| | - Julalak Chuprom
- School of Allied Health Sciences, Southeast Asia Water Team (SEA Water Team) and World Union for Herbal Drug Discovery (WUHeDD), Walailak University, Nakhon Si Thammarat, Thailand
| | - Watcharapong Mitsuwan
- Akkhraratchakumari Veterinary College and Research Center of Excellence in Innovation of Essential Oil, Walailak University, Nakhon Si Thammarat, Thailand
| | - Sirirat Surinkaew
- Department of Medical Technology, School of Allied Health Sciences and Research Excellence Center for Innovation and Health Products (RECIHP), Walailak University, Nakhon Si Thammarat, Thailand
| | - Rachasak Boonhok
- Department of Medical Technology, School of Allied Health Sciences and Research Excellence Center for Innovation and Health Products (RECIHP), Walailak University, Nakhon Si Thammarat, Thailand
| | - Alok K. Paul
- School of Pharmacy and Pharmacology, University of Tasmania, TAS, Australia
| | - Tooba Mahboob
- School of Allied Health Sciences, Southeast Asia Water Team (SEA Water Team) and World Union for Herbal Drug Discovery (WUHeDD), Walailak University, Nakhon Si Thammarat, Thailand
| | - Najme Sadat Abtahi
- Department of Clinical Biochemistry, Faculty of Medicine International Campus, Shahid Sadoughi University of Medical Sciences, Yazd, Iran
| | - Tajudeen O. Jimoh
- Department of Pharmacognosy and Pharmaceutical Botany, Faculty of Pharmaceutical Sciences, Chulalongkorn University, Bangkok, Thailand
- Department of Biochemistry, Faculty of Health Sciences, Islamic University in Uganda, Kampala, Uganda
| | - Sónia M.R. Oliveira
- CICECO-Aveiro Institute of Materials, University of Aveiro, Aveiro, Portugal
- Hunter Medical Research Institute, NSW, Australia
| | - Madhu Gupta
- Department of Pharmaceutics, Delhi Pharmaceutical Sciences and Research University, New Delhi, India
| | - Chea Sin
- Faculty of Pharmacy, University of Puthisastra, Phnom Penh, Cambodia
| | - Maria de Lourdes Pereira
- CICECO-Aveiro Institute of Materials, University of Aveiro, Aveiro, Portugal
- Department of Medical Sciences, University of Aveiro, Aveiro, Portugal
| | - Polrat Wilairatana
- Department of Clinical Tropical Medicine, Faculty of Tropical Medicine, Mahidol University, Bangkok, Thailand
| | - Christophe Wiart
- Institute for Tropical Biology & Conservation, University Malaysia Sabah, Sabah, Malaysia
| | - Mohammed Rahmatullah
- Department of Biotechnology & Genetic Engineering, University of Development Alternative, Dhaka, Bangladesh
| | - Karma G. Dolma
- Department of Microbiology, Sikkim Manipal Institute of Medical Sciences, Sikkim Manipal University, Sikkim, India
| | - Veeranoot Nissapatorn
- School of Allied Health Sciences, Southeast Asia Water Team (SEA Water Team) and World Union for Herbal Drug Discovery (WUHeDD), Walailak University, Nakhon Si Thammarat, Thailand
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17
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Sama-ae I, Sangkanu S, Siyadatpanah A, Norouzi R, Chuprom J, Mitsuwan W, Surinkaew S, Boonhok R, Paul AK, Mahboob T, Abtahi NS, Jimoh TO, Oliveira SM, Gupta M, Sin C, de Lourdes Pereira M, Wilairatana P, Wiart C, Rahmatullah M, Dolma KG, Nissapatorn V. Targeting Acanthamoeba proteins interaction with flavonoids of Propolis extract by in vitro and in silico studies for promising therapeutic effects. F1000Res 2022; 11:1274. [PMID: 36936052 PMCID: PMC10015121.3 DOI: 10.12688/f1000research.126227.3] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Accepted: 03/15/2023] [Indexed: 03/29/2023] Open
Abstract
Background : Propolis is a natural resinous mixture produced by bees. It provides beneficial effects on human health in the treatment/management of many diseases. The present study was performed to demonstrate the anti- Acanthamoeba activity of ethanolic extracts of Propolis samples from Iran. The interactions of the compounds and essential proteins of Acanthamoeba were also visualized through docking simulation. Methods: The minimal inhibitory concentrations (MICs) of Propolis extract against Acanthamoeba trophozoites and cysts was determined in vitro. In addition, two-fold dilutions of each of agents were tested for encystment, excystment and adhesion inhibitions. Three major compounds of Propolis extract such as chrysin, tectochrysin and pinocembrin have been selected in molecular docking approach to predict the compounds that might be responsible for encystment, excystment and adhesion inhibitions of A. castellanii. Furthermore, to confirm the docking results, molecular dynamics (MD) simulations were also carried out for the most promising two ligand-pocket complexes from docking studies. Results : The minimal inhibitory concentrations (MICs) 62.5 and 125 µg/mL of the most active Propolis extract were assessed in trophozoites stage of Acanthamoeba castellanii ATCC30010 and ATCC50739, respectively. At concentrations lower than their MICs values (1/16 MIC), Propolis extract revealed inhibition of encystation. However, at 1/2 MIC, it showed a potential inhibition of excystation and anti-adhesion. The molecular docking and dynamic simulation revealed the potential capability of Pinocembrin to form hydrogen bonds with A. castellanii Sir2 family protein (AcSir2), an encystation protein of high relevance for this process in Acanthamoeba. Conclusions : The results provided a candidate for the development of therapeutic drugs against Acanthamoeba infection. In vivo experiments and clinical trials are necessary to support this claim.
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Affiliation(s)
- Imran Sama-ae
- Department of Medical Technology, School of Allied Health Sciences and Center of Excellence Research for Melioidosis and Microorganisms (CERMM), Walailak University, Nakhon Si Thammarat, Thailand
| | - Suthinee Sangkanu
- School of Allied Health Sciences, Southeast Asia Water Team (SEA Water Team) and World Union for Herbal Drug Discovery (WUHeDD), Walailak University, Nakhon Si Thammarat, Thailand
| | - Abolghasem Siyadatpanah
- Department of Microbiology, School of Medicine, Infectious Diseases Research Center, Gonabad University of Medical Sciences, Gonabad, Iran
- Ferdows School of Paramedical and Health, Birjand University of Medical Sciences, Birjand, Iran
| | - Roghayeh Norouzi
- Department of Pathobiology, Faculty of Veterinary Medicine, University of Tabriz, Tabriz, Iran
| | - Julalak Chuprom
- School of Allied Health Sciences, Southeast Asia Water Team (SEA Water Team) and World Union for Herbal Drug Discovery (WUHeDD), Walailak University, Nakhon Si Thammarat, Thailand
| | - Watcharapong Mitsuwan
- Akkhraratchakumari Veterinary College and Research Center of Excellence in Innovation of Essential Oil, Walailak University, Nakhon Si Thammarat, Thailand
| | - Sirirat Surinkaew
- Department of Medical Technology, School of Allied Health Sciences and Research Excellence Center for Innovation and Health Products (RECIHP), Walailak University, Nakhon Si Thammarat, Thailand
| | - Rachasak Boonhok
- Department of Medical Technology, School of Allied Health Sciences and Research Excellence Center for Innovation and Health Products (RECIHP), Walailak University, Nakhon Si Thammarat, Thailand
| | - Alok K. Paul
- School of Pharmacy and Pharmacology, University of Tasmania, TAS, Australia
| | - Tooba Mahboob
- School of Allied Health Sciences, Southeast Asia Water Team (SEA Water Team) and World Union for Herbal Drug Discovery (WUHeDD), Walailak University, Nakhon Si Thammarat, Thailand
| | - Najme Sadat Abtahi
- Department of Clinical Biochemistry, Faculty of Medicine International Campus, Shahid Sadoughi University of Medical Sciences, Yazd, Iran
| | - Tajudeen O. Jimoh
- Department of Pharmacognosy and Pharmaceutical Botany, Faculty of Pharmaceutical Sciences, Chulalongkorn University, Bangkok, Thailand
- Department of Biochemistry, Faculty of Health Sciences, Islamic University in Uganda, Kampala, Uganda
| | - Sónia M.R. Oliveira
- CICECO-Aveiro Institute of Materials, University of Aveiro, Aveiro, Portugal
- Hunter Medical Research Institute, NSW, Australia
| | - Madhu Gupta
- Department of Pharmaceutics, Delhi Pharmaceutical Sciences and Research University, New Delhi, India
| | - Chea Sin
- Faculty of Pharmacy, University of Puthisastra, Phnom Penh, Cambodia
| | - Maria de Lourdes Pereira
- CICECO-Aveiro Institute of Materials, University of Aveiro, Aveiro, Portugal
- Department of Medical Sciences, University of Aveiro, Aveiro, Portugal
| | - Polrat Wilairatana
- Department of Clinical Tropical Medicine, Faculty of Tropical Medicine, Mahidol University, Bangkok, Thailand
| | - Christophe Wiart
- Institute for Tropical Biology & Conservation, University Malaysia Sabah, Sabah, Malaysia
| | - Mohammed Rahmatullah
- Department of Biotechnology & Genetic Engineering, University of Development Alternative, Dhaka, Bangladesh
| | - Karma G. Dolma
- Department of Microbiology, Sikkim Manipal Institute of Medical Sciences, Sikkim Manipal University, Sikkim, India
| | - Veeranoot Nissapatorn
- School of Allied Health Sciences, Southeast Asia Water Team (SEA Water Team) and World Union for Herbal Drug Discovery (WUHeDD), Walailak University, Nakhon Si Thammarat, Thailand
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18
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Sama-ae I, Sangkanu S, Siyadatpanah A, Norouzi R, Chuprom J, Mitsuwan W, Surinkaew S, Boonhok R, Paul AK, Mahboob T, Abtahi NS, Jimoh TO, Oliveira SM, Gupta M, Sin C, de Lourdes Pereira M, Wilairatana P, Wiart C, Rahmatullah M, Dolma KG, Nissapatorn V. Targeting Acanthamoeba proteins interaction with flavonoids of Propolis extract by in vitro and in silico studies for promising therapeutic effects. F1000Res 2022; 11:1274. [PMID: 36936052 PMCID: PMC10015121 DOI: 10.12688/f1000research.126227.2] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Accepted: 01/31/2023] [Indexed: 02/10/2023] Open
Abstract
Background : Propolis is a natural resinous mixture produced by bees. It provides beneficial effects on human health in the treatment/management of many diseases. The present study was performed to demonstrate the anti- Acanthamoeba activity of ethanolic extracts of Propolis samples from Iran. The interactions of the compounds and essential proteins of Acanthamoeba were also visualized through docking simulation. Methods: The minimal inhibitory concentrations (MICs) of Propolis extract against Acanthamoeba trophozoites and cysts was determined in vitro. In addition, two-fold dilutions of each of agents were tested for encystment, excystment and adhesion inhibitions. Three major compounds of Propolis extract such as chrysin, tectochrysin and pinocembrin have been selected in molecular docking approach to predict the compounds that might be responsible for encystment, excystment and adhesion inhibitions of A. castellanii. Furthermore, to confirm the docking results, molecular dynamics (MD) simulations were also carried out for the most promising two ligand-pocket complexes from docking studies. Results : The minimal inhibitory concentrations (MICs) 62.5 and 125 µg/mL of the most active Propolis extract were assessed in trophozoites stage of Acanthamoeba castellanii ATCC30010 and ATCC50739, respectively. At concentrations lower than their MICs values (1/16 MIC), Propolis extract revealed inhibition of encystation. However, at 1/2 MIC, it showed a potential inhibition of excystation and anti-adhesion. The molecular docking and dynamic simulation revealed the potential capability of Pinocembrin to form hydrogen bonds with A. castellanii Sir2 family protein (AcSir2), an encystation protein of high relevance for this process in Acanthamoeba. Conclusions : The results provided a candidate for the development of therapeutic drugs against Acanthamoeba infection. In vivo experiments and clinical trials are necessary to support this claim.
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Affiliation(s)
- Imran Sama-ae
- Department of Medical Technology, School of Allied Health Sciences and Center of Excellence Research for Melioidosis and Microorganisms (CERMM), Walailak University, Nakhon Si Thammarat, Thailand
| | - Suthinee Sangkanu
- School of Allied Health Sciences, Southeast Asia Water Team (SEA Water Team) and World Union for Herbal Drug Discovery (WUHeDD), Walailak University, Nakhon Si Thammarat, Thailand
| | - Abolghasem Siyadatpanah
- Ferdows School of Paramedical and Health, Birjand University of Medical Sciences, Birjand, Iran
- Department of Microbiology, School of Medicine, Infectious Diseases Research Center, Gonabad University of Medical Sciences, Gonabad, Iran
| | - Roghayeh Norouzi
- Department of Pathobiology, Faculty of Veterinary Medicine, University of Tabriz, Tabriz, Iran
| | - Julalak Chuprom
- School of Allied Health Sciences, Southeast Asia Water Team (SEA Water Team) and World Union for Herbal Drug Discovery (WUHeDD), Walailak University, Nakhon Si Thammarat, Thailand
| | - Watcharapong Mitsuwan
- Akkhraratchakumari Veterinary College and Research Center of Excellence in Innovation of Essential Oil, Walailak University, Nakhon Si Thammarat, Thailand
| | - Sirirat Surinkaew
- Department of Medical Technology, School of Allied Health Sciences and Research Excellence Center for Innovation and Health Products (RECIHP), Walailak University, Nakhon Si Thammarat, Thailand
| | - Rachasak Boonhok
- Department of Medical Technology, School of Allied Health Sciences and Research Excellence Center for Innovation and Health Products (RECIHP), Walailak University, Nakhon Si Thammarat, Thailand
| | - Alok K. Paul
- School of Pharmacy and Pharmacology, University of Tasmania, TAS, Australia
| | - Tooba Mahboob
- School of Allied Health Sciences, Southeast Asia Water Team (SEA Water Team) and World Union for Herbal Drug Discovery (WUHeDD), Walailak University, Nakhon Si Thammarat, Thailand
| | - Najme Sadat Abtahi
- Department of Clinical Biochemistry, Faculty of Medicine International Campus, Shahid Sadoughi University of Medical Sciences, Yazd, Iran
| | - Tajudeen O. Jimoh
- Department of Pharmacognosy and Pharmaceutical Botany, Faculty of Pharmaceutical Sciences, Chulalongkorn University, Bangkok, Thailand
- Department of Biochemistry, Faculty of Health Sciences, Islamic University in Uganda, Kampala, Uganda
| | - Sónia M.R. Oliveira
- CICECO-Aveiro Institute of Materials, University of Aveiro, Aveiro, Portugal
- Hunter Medical Research Institute, NSW, Australia
| | - Madhu Gupta
- Department of Pharmaceutics, Delhi Pharmaceutical Sciences and Research University, New Delhi, India
| | - Chea Sin
- Faculty of Pharmacy, University of Puthisastra, Phnom Penh, Cambodia
| | - Maria de Lourdes Pereira
- CICECO-Aveiro Institute of Materials, University of Aveiro, Aveiro, Portugal
- Department of Medical Sciences, University of Aveiro, Aveiro, Portugal
| | - Polrat Wilairatana
- Department of Clinical Tropical Medicine, Faculty of Tropical Medicine, Mahidol University, Bangkok, Thailand
| | - Christophe Wiart
- Institute for Tropical Biology & Conservation, University Malaysia Sabah, Sabah, Malaysia
| | - Mohammed Rahmatullah
- Department of Biotechnology & Genetic Engineering, University of Development Alternative, Dhaka, Bangladesh
| | - Karma G. Dolma
- Department of Microbiology, Sikkim Manipal Institute of Medical Sciences, Sikkim Manipal University, Sikkim, India
| | - Veeranoot Nissapatorn
- School of Allied Health Sciences, Southeast Asia Water Team (SEA Water Team) and World Union for Herbal Drug Discovery (WUHeDD), Walailak University, Nakhon Si Thammarat, Thailand
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19
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Abstract
Entamoeba histolytica, a protozoan parasite, causes amoebiasis in humans. Amoebiasis transmission is solely mediated by chitin-walled cysts, which are produced in the large intestine of humans from proliferative trophozoites by a cell differentiation process called encystation. Resistance to environmental stresses, an essential characteristic for transmission, is attributed to the cyst wall, which is constructed from chitin and several protein components, including chitinase. Chitinase may play a key role in cyst wall formation; however, this has not been confirmed. Here, to elucidate the physiological role of chitinase during Entamoeba encystation, we identified a new chitinase inhibitor, 2,6-dichloro-4-[2-(1-piperazinyl)-4-pyridinyl]-N-(1,3,5-trimethyl-1H-pyrazol-4-yl)-benzenesulfonamide, by recombinant-Entamoeba chitinase-based screening of 400 Pathogen Box chemicals. This compound dose dependently inhibited native chitinase associated with Entamoeba invadens encystation, a model for E. histolytica encystation, with an 50% inhibitory concentration (IC50) of ∼0.6 μM, which is comparable to the IC50s (0.2 to 2.5 μM) for recombinant E. histolytica and E. invadens chitinases. Furthermore, the addition of this compound to E. invadens encystation-inducing cultures increased the generation of cyst walls with an abnormal shape, the most characteristic of which was a "pot-like structure." A similar structure also appeared in standard culture, but at a far lower frequency. These results indicate that chitinase inhibition increases the number of abnormal encysting cells, thereby significantly reducing the efficiency of cyst formation. Transmission electron microscopy showed that compound-treated encysting cells formed an abnormally loose cyst wall and an unusual gap between the cyst wall and cell membrane. Hence, Entamoeba chitinase is required for the formation of mature round cysts. IMPORTANCE Amoebiasis is caused by Entamoeba histolytica infection and is transmitted by dormant Entamoeba cells or cysts. Cysts need to be tolerant to severe environmental stresses faced outside and inside a human host. To confer this resistance, Entamoeba parasites synthesize a wall structure around the cell during cyst formation. This cyst wall consists of chitin and several protein components, including chitinase. The physiological roles of these components are not fully understood. Here, to elucidate the role of chitinase during cyst formation, we identified a new chitinase inhibitor by screening a library of 400 compounds. Using this inhibitor, we showed that chitinase inhibition causes the formation of abnormal cyst walls, the most characteristic of which is a "pot-like structure." This results in decreased production of mature cysts. Chitinase is therefore required for Entamoeba to produce mature cysts for transmission to a new host.
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20
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Boonhok R, Sangkanu S, Norouzi R, Siyadatpanah A, Mirzaei F, Mitsuwan W, Charong N, Wisessombat S, Pereira MDL, Rahmatullah M, Wilairatana P, Wiart C, Tabo HA, Dolma KG, Nissapatorn V. Amoebicidal activity of Cassia angustifolia extract and its effect on Acanthamoeba triangularis autophagy-related gene expression at the transcriptional level. Parasitology 2021; 148:1074-1082. [PMID: 33966667 PMCID: PMC11010062 DOI: 10.1017/s0031182021000718] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/16/2020] [Revised: 04/07/2021] [Accepted: 04/29/2021] [Indexed: 12/30/2022]
Abstract
Cassia angustifolia Vahl. plant is used for many therapeutic purposes, for example, in people with constipation, skin diseases, including helminthic and parasitic infections. In our study, we demonstrated an amoebicidal activity of C. angustifolia extract against Acanthamoeba triangularis trophozoite at a micromolar level. Scanning electron microscopy (SEM) images displayed morphological changes in the Acanthamoeba trophozoite, which included the formation of pores in cell membrane and the membrane rupture. In addition to the amoebicidal activity, effects of the extract on surviving trophozoites were observed, which included cyst formation and vacuolization by a microscope and transcriptional expression of Acanthamoeba autophagy in response to the stress by quantitative polymerase chain reaction. Our data showed that the surviving trophozoites were not transformed into cysts and the trophozoite number with enlarged vacuole was not significantly different from that of untreated control. Molecular analysis data demonstrated that the mRNA expression of AcATG genes was slightly changed. Interestingly, AcATG16 decreased significantly at 12 h post treatment, which may indicate a transcriptional regulation by the extract or a balance of intracellular signalling pathways in response to the stress, whereas AcATG3 and AcATG8b remained unchanged. Altogether, these data reveal the anti-Acanthamoeba activity of C. angustifolia extract and the autophagic response in the surviving trophozoites under the plant extract pressure, along with data on the formation of cysts. These represent a promising plant for future drug development. However, further isolation and purification of an active compound and cytotoxicity against human cells are needed, including a study on the autophagic response at the protein level.
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Affiliation(s)
- Rachasak Boonhok
- Department of Medical Technology, School of Allied Health Sciences, Walailak University, Nakhon Si Thammarat80160, Thailand
| | - Suthinee Sangkanu
- School of Allied Health Sciences, Southeast Asia Water Team (SEA Water Team) and World Union for Herbal Drug Discovery (WUHeDD), and Research Excellence Center for Innovation and Health Products, Walailak University, Nakhon Si Thammarat80160, Thailand
| | - Roghayeh Norouzi
- Department of Pathobiology, Faculty of Veterinary Medicine, University of Tabriz, Tabriz51664, Iran
| | - Abolghasem Siyadatpanah
- Ferdows School of Paramedical and Health, Birjand University of Medical Sciences, Birjand9717853577, Iran
| | - Farzaneh Mirzaei
- Department Parasitology and Mycology, School of Medicine, Shahid Sadoughi University of Medical Sciences, Yazd14188-15971, Iran
| | - Watcharapong Mitsuwan
- School of Allied Health Sciences, Southeast Asia Water Team (SEA Water Team) and World Union for Herbal Drug Discovery (WUHeDD), and Research Excellence Center for Innovation and Health Products, Walailak University, Nakhon Si Thammarat80160, Thailand
- Akkhraratchakumari Veterinary College, and Research Center of Excellence in Innovation of Essential Oil, Walailak University, Nakhon Si Thammarat80160, Thailand
| | - Nurdina Charong
- Department of Medical Technology, School of Allied Health Sciences, Walailak University, Nakhon Si Thammarat80160, Thailand
| | - Sueptrakool Wisessombat
- Department of Medical Technology, School of Allied Health Sciences, Walailak University, Nakhon Si Thammarat80160, Thailand
| | - Maria de Lourdes Pereira
- Department of Medical Sciences, CICECO-Aveiro Institute of Materials, University of Aveiro, Aveiro3810-193, Portugal
| | - Mohammed Rahmatullah
- Department of Biotechnology and Genetic Engineering, University of Development Alternative Lalmatia, Dhaka1209, Bangladesh
| | - Polrat Wilairatana
- Department of Clinical Tropical Medicine, Faculty of Tropical Medicine, Mahidol University, Bangkok10400, Thailand
| | - Christophe Wiart
- School of Pharmacy, University of Nottingham Malaysia Campus, Selangor43500, Malaysia
| | - Hazel Anne Tabo
- Biological Sciences Department, College of Science and Computer Studies, De La Salle University-Dasmarinas, Cavite4115, Philippines
| | - Karma G. Dolma
- Department of Microbiology, Sikkim Manipal Institute of Medical Sciences (SMIMS), Gangtok, Sikkim737102, India
| | - Veeranoot Nissapatorn
- Department of Medical Technology, School of Allied Health Sciences, Walailak University, Nakhon Si Thammarat80160, Thailand
- School of Allied Health Sciences, Southeast Asia Water Team (SEA Water Team) and World Union for Herbal Drug Discovery (WUHeDD), and Research Excellence Center for Innovation and Health Products, Walailak University, Nakhon Si Thammarat80160, Thailand
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21
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Boonhok R, Sangkanu S, Chuprom J, Srisuphanunt M, Norouzi R, Siyadatpanah A, Mirzaei F, Mitsuwan W, Wisessombat S, de Lourdes Pereira M, Rahmatullah M, Wilairatana P, Wiart C, Ling LC, Dolma KG, Nissapatorn V. Peganum harmala Extract Has Antiamoebic Activity to Acanthamoeba triangularis Trophozoites and Changes Expression of Autophagy-Related Genes. Pathogens 2021; 10:842. [PMID: 34357992 PMCID: PMC8308471 DOI: 10.3390/pathogens10070842] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/08/2021] [Revised: 07/02/2021] [Accepted: 07/02/2021] [Indexed: 02/03/2023] Open
Abstract
Peganum harmala, a well-known medicinal plant, has been used for several therapeutic purposes as it contains numerous pharmacological active compounds. Our study reported an anti-parasitic activity of P. harmala seed extract against Acanthamoeba triangularis. The stress induced by the extract on the surviving trophozoites for Acanthamoeba encystation and vacuolization was examined by microscopy, and transcriptional expression of Acanthamoeba autophagy-related genes was investigated by quantitative PCR. Our results showed that the surviving trophozoites were not transformed into cysts, and the number of trophozoites with enlarged vacuoles were not significantly different from that of untreated control. Molecular analysis data demonstrated that the mRNA expression of tested AcATG genes, i.e., ATG3, ATG8b, and ATG16, was at a basal level along the treatment. However, upregulation of AcATG16 at 24 h post treatment was observed, which may indicate an autophagic activity of this protein in response to the stress. Altogether, these data revealed the anti-Acanthamoeba activity of P. harmala extract and indicated the association of autophagy mRNA expression and cyst formation under the extract stress, representing a promising plant for future drug development. However, further identification of an active compound and a study of autophagy at the protein level are needed.
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Affiliation(s)
- Rachasak Boonhok
- Department of Medical Technology, School of Allied Health Sciences, Walailak University, Nakhon Si Thammarat 80160, Thailand; (R.B.); (M.S.); (S.W.)
| | - Suthinee Sangkanu
- Research Excellence Center for Innovation and Health Products (RECIHP), School of Allied Health Sciences, Southeast Asia Water Team (SEA Water Team) and World Union for Herbal Drug Discovery (WUHeDD), Walailak University, Nakhon Si Thammarat 80160, Thailand; (S.S.); (J.C.)
| | - Julalak Chuprom
- Research Excellence Center for Innovation and Health Products (RECIHP), School of Allied Health Sciences, Southeast Asia Water Team (SEA Water Team) and World Union for Herbal Drug Discovery (WUHeDD), Walailak University, Nakhon Si Thammarat 80160, Thailand; (S.S.); (J.C.)
| | - Mayuna Srisuphanunt
- Department of Medical Technology, School of Allied Health Sciences, Walailak University, Nakhon Si Thammarat 80160, Thailand; (R.B.); (M.S.); (S.W.)
| | - Roghayeh Norouzi
- Department of Pathobiology, Faculty of Veterinary Medicine, University of Tabriz, Tabriz 5166616471, Iran;
| | - Abolghasem Siyadatpanah
- Ferdows School of Paramedical and Health, Birjand University of Medical Sciences, Birjand 9717853577, Iran;
| | - Farzaneh Mirzaei
- Department Parasitology and Mycology, School of Medicine, Shahid Sadoughi University of Medical Sciences, Yazd 14188-15971, Iran;
| | - Watcharapong Mitsuwan
- Akkhraratchakumari Veterinary College and Research Center of Excellence in Innovation of Essential Oil, Walailak University, Nakhon Si Thammarat 80160, Thailand;
| | - Sueptrakool Wisessombat
- Department of Medical Technology, School of Allied Health Sciences, Walailak University, Nakhon Si Thammarat 80160, Thailand; (R.B.); (M.S.); (S.W.)
| | - Maria de Lourdes Pereira
- CICECO-Aveiro Institute of Materials and Department of Medical Sciences, University of Aveiro, 3810-193 Aveiro, Portugal;
| | - Mohammed Rahmatullah
- Department of Biotechnology and Genetic Engineering, University of Development Alternative, Lalmatia, Dhaka 1209, Bangladesh;
| | - Polrat Wilairatana
- Department of Clinical Tropical Medicine, Faculty of Tropical Medicine, Mahidol University, Bangkok 10400, Thailand
| | - Christophe Wiart
- School of Pharmacy, University of Nottingham Malaysia Campus, Selangor 43500, Malaysia;
| | - Lim Chooi Ling
- Division of Applied Biomedical Science and Biotechnology, School of Health Sciences, International Medical University, Kuala Lumpur 57000, Malaysia;
| | - Karma G. Dolma
- Department of Microbiology, Sikkim Manipal Institute of Medical Sciences (SMIMS), Sikkim 737102, India;
| | - Veeranoot Nissapatorn
- Department of Medical Technology, School of Allied Health Sciences, Walailak University, Nakhon Si Thammarat 80160, Thailand; (R.B.); (M.S.); (S.W.)
- Research Excellence Center for Innovation and Health Products (RECIHP), School of Allied Health Sciences, Southeast Asia Water Team (SEA Water Team) and World Union for Herbal Drug Discovery (WUHeDD), Walailak University, Nakhon Si Thammarat 80160, Thailand; (S.S.); (J.C.)
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22
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Affiliation(s)
- Naveed Ahmed Khan
- Department of Clinical Sciences, College of Medicine, University of Sharjah, University City, Sharjah, United Arab Emirates
| | - Jibran Sualeh Muhammad
- Department of Basic Medical Sciences, College of Medicine, University of Sharjah, University City, Sharjah, United Arab Emirates
| | - Ruqaiyyah Siddiqui
- College of Arts and Sciences, University of Sharjah, University City, Sharjah, United Arab Emirates
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23
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Thomas EB, Sutanto R, Johnson RS, Shih HW, Alas GCM, Krtková J, MacCoss MJ, Paredez AR. Staging Encystation Progression in Giardia lamblia Using Encystation-Specific Vesicle Morphology and Associating Molecular Markers. Front Cell Dev Biol 2021; 9:662945. [PMID: 33987184 PMCID: PMC8111296 DOI: 10.3389/fcell.2021.662945] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/01/2021] [Accepted: 03/15/2021] [Indexed: 01/24/2023] Open
Abstract
Differentiation into environmentally resistant cysts is required for transmission of the ubiquitous intestinal parasite Giardia lamblia. Encystation in Giardia requires the production, processing and transport of Cyst Wall Proteins (CWPs) in developmentally induced, Golgi-like, Encystation Specific Vesicles (ESVs). Progress through this trafficking pathway can be followed by tracking CWP localization over time. However, there is no recognized system to distinguish the advancing stages of this process which can complete at variable rates depending on how encystation is induced. Here, we propose a staging system for encysting Giardia based on the morphology of CWP1-stained ESVs. We demonstrate the molecular distinctiveness of maturing ESVs at these stages by following GlRab GTPases through encystation. Previously, we established that Giardia’s sole Rho family GTPase, GlRac, associates with ESVs and has a role in regulating their maturation and the secretion of their cargo. As a proof of principle, we delineate the relationship between GlRac and ESV stages. Through proteomic studies, we identify putative interactors of GlRac that could be used as additional ESV stage markers. This staging system provides a common descriptor of ESV maturation regardless of the source of encysting cells. Furthermore, the identified set of molecular markers for ESV stages will be a powerful tool for characterizing trafficking mutants that impair ESV maturation and morphology.
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Affiliation(s)
- Elizabeth B Thomas
- Department of Biology, University of Washington, Seattle, WA, United States
| | - Renaldo Sutanto
- Department of Biology, University of Washington, Seattle, WA, United States.,Department of Bioengineering and Therapeutic Sciences, University of California, San Francisco, San Francisco, CA, United States
| | - Richard S Johnson
- Department of Genome Sciences, University of Washington, Seattle, WA, United States
| | - Han-Wei Shih
- Department of Biology, University of Washington, Seattle, WA, United States
| | - Germain C M Alas
- Department of Biology, University of Washington, Seattle, WA, United States
| | - Jana Krtková
- Department of Experimental Plant Biology, Faculty of Science, Charles University, Prague, Czechia
| | - Michael J MacCoss
- Department of Genome Sciences, University of Washington, Seattle, WA, United States
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24
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Wesel J, Shuman J, Bastuzel I, Dickerson J, Ingram-Smith C. Encystation of Entamoeba histolytica in Axenic Culture. Microorganisms 2021; 9:873. [PMID: 33919506 PMCID: PMC8074197 DOI: 10.3390/microorganisms9040873] [Citation(s) in RCA: 14] [Impact Index Per Article: 4.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/09/2021] [Revised: 04/15/2021] [Accepted: 04/16/2021] [Indexed: 12/16/2022] Open
Abstract
Entamoeba histolytica is a parasitic protozoan that causes amoebic dysentery, which affects approximately 90 million people each year worldwide. E. histolytica is transmitted through ingestion of food and water contaminated with the cyst form, which undergoes excystation in the small intestine to the trophozoite form that colonizes the large intestine. The reptile pathogen Entamoeba invadens has served as a model for studying stage conversion between the trophozoite and cyst form due to lack of reproducible encystation of E. histolytica in the laboratory. Although much has been learned about encystation and excystation using E. invadens, the findings do not fully translate to E. histolytica due to the extensive genetic and host differences between these species. Here, we present the first reproducible encystation of E. histolytica in vitro. The cysts produced were viable and displayed the four characteristic hallmarks: round shape, chitinous cell wall, tetranucleation, and detergent resistance. Using flow cytometry analysis, glucose limitation and high cell density were key for encystation, as for E. invadens. Entry into encystation was enhanced by the short-chain fatty acids acetate and propionate, unlike for E. invadens. This new model will now allow the further study of E. histolytica stage conversion, transmission, and treatment.
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Affiliation(s)
- Jordan Wesel
- Department of Genetics and Biochemistry, Clemson University, Clemson, SC 29634, USA; (J.W.); (J.S.); (I.B.); (J.D.)
- Eukaryotic Pathogens Innovation Center, Clemson University, Clemson, SC 29634, USA
| | - Jennifer Shuman
- Department of Genetics and Biochemistry, Clemson University, Clemson, SC 29634, USA; (J.W.); (J.S.); (I.B.); (J.D.)
- Eukaryotic Pathogens Innovation Center, Clemson University, Clemson, SC 29634, USA
| | - Irem Bastuzel
- Department of Genetics and Biochemistry, Clemson University, Clemson, SC 29634, USA; (J.W.); (J.S.); (I.B.); (J.D.)
- Eukaryotic Pathogens Innovation Center, Clemson University, Clemson, SC 29634, USA
| | - Julie Dickerson
- Department of Genetics and Biochemistry, Clemson University, Clemson, SC 29634, USA; (J.W.); (J.S.); (I.B.); (J.D.)
- Eukaryotic Pathogens Innovation Center, Clemson University, Clemson, SC 29634, USA
| | - Cheryl Ingram-Smith
- Department of Genetics and Biochemistry, Clemson University, Clemson, SC 29634, USA; (J.W.); (J.S.); (I.B.); (J.D.)
- Eukaryotic Pathogens Innovation Center, Clemson University, Clemson, SC 29634, USA
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25
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Abstract
Multicellularity evolved repeatedly in the history of life, but how it unfolded varies greatly between different lineages. Dictyostelid social amoebas offer a good system to study the evolution of multicellular complexity, with a well-resolved phylogeny and molecular genetic tools being available. We compare the life cycles of the Dictyostelids with closely related amoebozoans to show that complex life cycles were already present in the unicellular common ancestor of Dictyostelids. We propose frost resistance as an early driver of multicellular evolution in Dictyostelids and show that the cell signalling pathways for differentiating spore and stalk cells evolved from that for encystation. The stalk cell differentiation program was further modified, possibly through gene duplication, to evolve a new cell type, cup cells, in Group 4 Dictyostelids. Studies in various multicellular organisms, including Dictyostelids, volvocine algae, and metazoans, suggest as a common principle in the evolution of multicellular complexity that unicellular regulatory programs for adapting to environmental change serve as "proto-cell types" for subsequent evolution of multicellular organisms. Later, new cell types could further evolve by duplicating and diversifying the "proto-cell type" gene regulatory networks.
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Affiliation(s)
- Koryu Kin
- School of Life Sciences, University of Dundee, Dundee DD1 5EH, UK;
- Institut de Biologia Evolutiva (CSIC-Universitat Pompeu Fabra), Passeig Marítim de la Barceloneta 37–49, 08003 Barcelona, Spain
| | - Pauline Schaap
- School of Life Sciences, University of Dundee, Dundee DD1 5EH, UK;
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26
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Lê HG, Ham AJ, Kang JM, Võ TC, Naw H, Sohn HJ, Shin HJ, Na BK. A Novel Cysteine Protease Inhibitor of Naegleria fowleri That Is Specifically Expressed during Encystation and at Mature Cysts. Pathogens 2021; 10:388. [PMID: 33804993 DOI: 10.3390/pathogens10040388] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/11/2021] [Revised: 03/21/2021] [Accepted: 03/22/2021] [Indexed: 11/26/2022] Open
Abstract
Naegleria fowleri is a free-living amoeba that is ubiquitous in diverse natural environments. It causes a fatal brain infection in humans known as primary amoebic meningoencephalitis. Despite the medical importance of the parasitic disease, there is a great lack of knowledge about the biology and pathogenicity of N. fowleri. In this study, we identified and characterized a novel cysteine protease inhibitor of N. fowleri (NfCPI). NfCPI is a typical cysteine protease inhibitor belonging to the cystatin family with a Gln-Val-Val-Ala-Gly (QVVAG) motif, a characteristic motif conserved in the cystatin family of proteins. Bacterially expressed recombinant NfCPI has a dimeric structure and exhibits inhibitory activity against several cysteine proteases including cathespin Bs of N. fowleri at a broad range of pH values. Expression profiles of nfcpi revealed that the gene was highly expressed during encystation and cyst of the amoeba. Western blot and immunofluorescence assays also support its high level of expression in cysts. These findings collectively suggest that NfCPI may play a critical role in encystation or cyst formation of N. fowleri by regulating cysteine proteases that may mediate encystation or mature cyst formation of the amoeba. More comprehensive studies to investigate the roles of NfCPI in encystation and its target proteases are necessary to elucidate the regulatory mechanism and the biological significance of NfCPI.
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27
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Mi-Ichi F, Ikeda K, Tsugawa H, Deloer S, Yoshida H, Arita M. Stage-Specific De Novo Synthesis of Very-Long-Chain Dihydroceramides Confers Dormancy to Entamoeba Parasites. mSphere 2021; 6:e00174-21. [PMID: 33731470 DOI: 10.1128/mSphere.00174-21] [Citation(s) in RCA: 7] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022] Open
Abstract
Amoebiasis is a parasitic disease caused by Entamoeba histolytica infection and is a serious public health problem worldwide due to ill-prepared preventive measures as well as its high morbidity and mortality rates. Amoebiasis transmission is solely mediated by cysts. Cysts are produced by the differentiation of proliferative trophozoites in a process termed "encystation." Entamoeba encystation is a fundamental cell differentiation process and proceeds with substantial changes in cell metabolites, components, and morphology, which occur sequentially in an orchestrated manner. Lipids are plausibly among these metabolites that function as key factors for encystation. However, a comprehensive lipid analysis has not been reported, and the involved lipid metabolic pathways remain largely unknown. Here, we exploited the state-of-the-art untargeted lipidomics and characterized 339 molecules of 17 lipid subclasses. Of these, dihydroceramide (Cer-NDS) was found to be among the most induced lipid species during encystation. Notably, in encysting cells, amounts of Cer-NDS containing very long N-acyl chains (≥26 carbon) were more than 30-fold induced as the terminal product of a de novo metabolic pathway. We also identified three ceramide synthase genes responsible for producing the very-long-chain Cer-NDS molecules. These genes were upregulated during encystation. Furthermore, these ceramide species were shown to be indispensable for generating membrane impermeability, a prerequisite for becoming dormant cyst that shows resistance to environmental assault inside and outside the host for transmission. Hence, the lipid subclass of Cer-NDS plays a crucial role for Entamoeba cell differentiation and morphogenesis by alternating the membrane properties.IMPORTANCE Entamoeba is a protozoan parasite that thrives in its niche by alternating its two forms between a proliferative trophozoite and dormant cyst. Cysts are the only form able to transmit to a new host and are differentiated from trophozoites in a process termed "encystation." During Entamoeba encystation, cell metabolites, components, and morphology drastically change, which occur sequentially in an orchestrated manner. Lipids are plausibly among these metabolites. However, the involved lipid species and their metabolic pathways remain largely unknown. Here, we identified dihydroceramides (Cer-NDSs) containing very long N-acyl chains (C26 to C30) as a key metabolite for Entamoeba encystation by our state-of-the-art untargeted lipidomics. We also showed that these Cer-NDSs are critical to generate the membrane impermeability, a prerequisite for this parasite to show dormancy as a cyst that repels substances and prevents water loss. Hence, ceramide metabolism is essential for Entamoeba to maintain the parasitic lifestyle.
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28
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Wang N, Sun H, Liu D, Jiang X, Zheng M, Zhu W, Liu Q, Zheng W, Feng X. Ac-HSP20 Is Associated With the Infectivity and Encystation of Acanthamoeba castellanii. Front Microbiol 2021; 11:595080. [PMID: 33510719 PMCID: PMC7835678 DOI: 10.3389/fmicb.2020.595080] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/15/2020] [Accepted: 12/01/2020] [Indexed: 11/15/2022] Open
Abstract
Acanthamoeba castellanii is a pathogenic and opportunistic free-living amoeba that causes Acanthamoeba keratitis (AK) and granulomatous amebic encephalitis (GAE) in immunocompromised individuals. The biological and pathogenic characterizations behind this opportunistic protozoan is not fully understood. This study aimed to determine the biological functions of heat shock protein (HSP)-20 of A. castellanii (Ac-HSP20) involved in the maintenance of life cycle and the infectivity of A. castellanii. Immunoscreening A. castellanii cDNA library with A. castellanii infected rabbit sera identified three positive clones, one of them was a putative heat shock protein (Ac-HSP20). The recombinant 23 kDa Ac-HSP20 protein (rAc-HSP20) was successfully expressed in Escherichia coli BL21 (DE3) and purified using metal affinity chromatography. The rabbits immunized with rAc-HSP20 produced high titer antibody (1:25,600). Immunolocalization with the antibody identified the expression of native Ac-HSP20 on the surface of both A. castellanii trophozoites and cysts. Further, Western blot with antibody identified that the expression of native Ac-HSP20 was 7.5 times higher in cysts than in trophozoites. Blocking Ac-HSP20 on the membrane of trophozoites with specific antibody or silencing Ac-hsp20 gene transcription by siRNA inhibited their transformation into cysts at the early stage but returned to normal at the late stage by stimulating the transcription of Ac-hsp20. Incubation of trophozoites with anti-Ac-HSP20 IgG increased macrophage-involved phagocytosis to the protozoa and inhibited trophozoite infectivity on the cornea of rabbits compared with that without antibody. Our study provides that Ac-HSP20 is a surface antigen involved in the encystation and infectivity of A. castellanii and thus an important target for vaccine and drug development.
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Affiliation(s)
- Ningning Wang
- Department of Pathogenic Biology, Jilin Medical University, Jilin City, China
| | - Hongyu Sun
- Department of Pathogenic Biology, Jilin Medical University, Jilin City, China
| | - Di Liu
- Department of Pathogenic Biology, Jilin Medical University, Jilin City, China
| | - Xiaoming Jiang
- Department of Pathogenic Biology, Jilin Medical University, Jilin City, China
| | - Meiyu Zheng
- Department of Pathogenic Biology, Jilin Medical University, Jilin City, China
| | - Wenhe Zhu
- Department of Pathogenic Biology, Jilin Medical University, Jilin City, China
| | - Quan Liu
- School of Life Sciences and Engineering, Foshan University, Foshan, China
| | - Wenyu Zheng
- Department of Microsurgery, Jilin City Central Hospital, Jilin City, China
| | - Xianmin Feng
- Department of Pathogenic Biology, Jilin Medical University, Jilin City, China
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Guillen N. Signals and signal transduction pathways in Entamoeba histolytica during the life cycle and when interacting with bacteria or human cells. Mol Microbiol 2020; 115:901-915. [PMID: 33249684 DOI: 10.1111/mmi.14657] [Citation(s) in RCA: 9] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/20/2020] [Revised: 11/22/2020] [Accepted: 11/23/2020] [Indexed: 01/17/2023]
Abstract
Entamoeba histolytica is the etiological agent of amebiasis in humans. This ameba parasite resides as a commensal in the intestine where it shares intestinal resources with the bacterial microbiome. In the intestinal ecosystem, the ameba encysts and eventually develops disease by invading the tissues. E. histolytica possesses cell surface receptors for the proper sensing of signals involved in encystation or sustaining parasite interaction with bacteria and human cells. Among those receptors are the Gal/GalNAc lectin, G protein-coupled receptors, and transmembrane kinases. In addition there are recently discovered, promising proteins, including orthologs of Toll-type receptors and β trefoil lectins. These proteins trigger a wide variety of signal transduction pathways; however, most of the players involved in the signaling pathways evoked in this parasite are unknown. This review provides an overview of amoebic receptors and their role in encystation, adherence to bacteria or human cells, as well as the reported intracellular signal transduction processes that they can trigger. This knowledge is essential for understanding the lifestyle of E. histolytica and its cytopathic effect on bacteria and human cells that are responsible for infection.
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Affiliation(s)
- Nancy Guillen
- Institut Pasteur, Centre National de la Recherche Scientifique, CNRS-ERL9195, Paris, France
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Sharma M, Morgado P, Zhang H, Ehrenkaufer G, Manna D, Singh U. Characterization of Extracellular Vesicles from Entamoeba histolytica Identifies Roles in Intercellular Communication That Regulates Parasite Growth and Development. Infect Immun 2020; 88:e00349-20. [PMID: 32719158 DOI: 10.1128/IAI.00349-20] [Citation(s) in RCA: 17] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/16/2020] [Accepted: 07/20/2020] [Indexed: 12/17/2022] Open
Abstract
Extracellular vesicles (EVs) secreted by eukaryotic and prokaryotic cells to transport lipids, proteins, and nucleic acids to the external environment have important roles in cell-cell communication through cargo transfer. We identified and characterized EVs from Entamoeba histolytica, a protozoan parasite and a human pathogen. Conditioned medium from amebic parasites contained particles consistent with the expected size and morphology of EVs. Mass spectrometry was used to characterize the EV proteome and showed that it was enriched in common exosome marker proteins, including proteins associated with vesicle formation, cell signaling, and metabolism, as well as cytoskeletal proteins. Additionally, the EVs were found to selectively package small RNAs (sRNA), which were protected within the vesicles against RNase treatment. Sequencing analysis of the sRNA contained in EVs revealed that the majority were 27 nucleotides (nt) in size and represented a subset of the cellular antisense small RNA population that has previously been characterized in Entamoeba RNA interference (RNAi) pathway proteins, including Argonaute, were also present in amebic EVs. Interestingly, we found that the amebic EVs impacted intercellular communication between parasites and altered encystation efficiency. EVs isolated from encysting parasites promoted encystation in other parasites, whereas EVs from metabolically active trophozoites impeded encystation. Overall, the data reveal that Entamoeba secrete EVs that are similar in size and shape to previously characterized exosomes from other organisms and that these EVs contain a defined protein and small RNA cargo and have roles in intercellular communication among parasites and influence growth kinetics.
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Krishnan D, Ghosh SK. Morphological and Motility Features of the Stable Bleb-Driven Monopodial Form of Entamoeba and Its Importance in Encystation. Infect Immun 2020; 88:e00903-19. [PMID: 32393510 DOI: 10.1128/IAI.00903-19] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/30/2019] [Accepted: 04/27/2020] [Indexed: 11/20/2022] Open
Abstract
Entamoeba histolytica and its reptilian counterpart and encystation model Entamoeba invadens formed a polarized monopodial morphology when treated with pentoxifylline. This morphology was propelled by retrograde flow of the cell surface resulting from a cyclic sol-gel conversion of cytoplasm and a stable bleb at the leading edge. Pentoxifylline treatment switched the unpolarized, adherent trophozoites to the nonadherent, stable bleb-driven form and altered the motility pattern from slow and random to fast, directionally persistent, and highly chemotactic. Interestingly, exogenously added adenosine produced multiple protrusions and random motility, an opposite phenotype to that of pentoxifylline. Thus, pentoxifylline, an adenosine antagonist, may be inducing the monopodial morphology by preventing lateral protrusions and restricting the leading edge to one site. The polarized form of E. invadens was aggregation competent, and time-lapse microscopy of encystation revealed its appearance during early hours, mediating the cell aggregation by directional cell migration. The addition of purine nucleotides to in vitro encystation culture prevented the formation of polarized morphology and inhibited the cell aggregation and, thus, the encystation, which further showed the importance of the polarized form in the Entamoeba life cycle. Cell polarity and motility are essential in the pathogenesis of Entamoeba parasites, and the stable bleb-driven polarized morphology of Entamoeba may also be important in invasive amoebiasis.
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Manna D, Lozano-Amado D, Ehrenkaufer G, Singh U. The NAD + Responsive Transcription Factor ERM-BP Functions Downstream of Cellular Aggregation and Is an Early Regulator of Development and Heat Shock Response in Entamoeba. Front Cell Infect Microbiol 2020; 10:363. [PMID: 32766170 PMCID: PMC7379229 DOI: 10.3389/fcimb.2020.00363] [Citation(s) in RCA: 8] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/09/2020] [Accepted: 06/11/2020] [Indexed: 12/20/2022] Open
Abstract
Entamoeba histolytica is a protozoan parasite and a major cause of dysentery and diarrheal disease in developing countries. Disease transmission from one host to another occurs via cysts which can survive in environmental extremes and are transmitted through contaminated food and water. Recent studies in our lab identified a novel transcription factor, Encystation Regulatory Motif- Binding Protein (ERM-BP), which is responsive to NAD+ and has an important role in encystation. The key residues important for ERM-BP function were demonstrated in vitro using recombinant protein. In this study we demonstrate the in vivo functional consequences of mutations in key domains and their impact on Entamoeba encystation. Our results show that mutations in the DNA binding domain (ERM-BP-DBM) and in the nicotinamidase domain (ERM-BP-C198A) lead to protein mis-localization in both trophozoites and cysts and significantly reduce encystation efficiency. Additionally, we showed that silencing of ERM-BP significantly decreased the size and number of multi-nucleated giant cells (MGC) that form during encystation, indicating that ERM-BP functions upstream of the cellular aggregation that precedes stage conversion. Dissection of epistatic interactions between ERM-BP and a second encystation-related transcription factor, NF-Y revealed that ERM-BP is upstream of NF-Y in controlling the developmental cascade and appears to be one of the earliest regulators of development identified to date in Entamoeba. We also demonstrated that ERM-BP is upregulated during heat stress in Entamoeba, another condition which increases intracellular NAD+ levels and that overexpression of ERM-BP makes E. histolytica and E. invadens parasites more resistant to heat stress. Overexpression of ERM-BP in E. histolytica also induced the formation of cyst-like quadrinucleated cells and formation of MGCs. Overall, our work has identified an important role of ERM-BP in Entamoeba stress response and links an NAD+-responsive transcription factor to both development and heat shock response. Characterization of stress and developmental cascades are important avenues to investigate for Entamoeba, an important human parasitic pathogen.
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Affiliation(s)
- Dipak Manna
- Division of Infectious Diseases, Stanford University School of Medicine, Stanford, CA, United States
| | - Daniela Lozano-Amado
- Division of Infectious Diseases, Stanford University School of Medicine, Stanford, CA, United States
| | - Gretchen Ehrenkaufer
- Division of Infectious Diseases, Stanford University School of Medicine, Stanford, CA, United States
| | - Upinder Singh
- Division of Infectious Diseases, Stanford University School of Medicine, Stanford, CA, United States
- Department of Microbiology and Immunology, Stanford University School of Medicine, Stanford, CA, United States
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Baig AM, Khan NA, Katyara P, Lalani S, Baig R, Nadeem M, Akbar N, Nazim F, Khaleeq A. 'Targeting the feast of a sleeping beast': Nutrient and mineral dependencies of encysted Acanthamoeba castellanii. Chem Biol Drug Des 2020; 97:18-27. [PMID: 32602961 DOI: 10.1111/cbdd.13755] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/16/2019] [Revised: 06/02/2020] [Accepted: 06/05/2020] [Indexed: 11/28/2022]
Abstract
Acanthamoeba spp. cause a corneal infection, Acanthamoeba keratitis (AK), and a cerebral infection, granulomatous amoebic encephalitis (GAE). Though aggressive chemotherapy has been able to kill the active trophozoite form of Acanthamoeba, the encysted form of this parasite has remained problematic to resist physiological concentrations of drugs. The emergence of encysted amoeba into active trophozoite form poses a challenge to eradicate this parasite. Acanthamoeba trophozoites have active metabolic machinery that furnishes energy in the form of ATPs by subjecting carbohydrates and lipids to undergo pathways including glycolysis and beta-oxidation of free fatty acids, respectively. However, very little is known about the metabolic preferences and dependencies of an encysted trophozoite on minerals or potential nutrients that it consumes to live in an encysted state. Here, we investigate the metabolic and nutrient preferences of the encysted trophozoite of Acanthamoeba castellanii and the possibility to target them by drugs that act on calcium ion dependencies of the encysted amoeba. The experimental assays, immunostaining coupled with bioinformatics tools show that the encysted Acanthamoeba uses diverse nutrient pathways to obtain energy in the quiescent encysted state. These findings highlight potential pathways that can be targeted in eradicating amoebae cysts successfully.
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Affiliation(s)
- Abdul Mannan Baig
- Department of Biological and Biomedical Sciences, Aga Khan University, Karachi, Pakistan
| | - Naveed Ahmed Khan
- Department of Biology, Chemistry and Environmental Sciences, College of Arts and Sciences, American University of Sharjah, Sharjah, United Arab Emirates
| | - Preet Katyara
- Department of Biological and Biomedical Sciences, Aga Khan University, Karachi, Pakistan
| | - Salima Lalani
- Department of Virus and Vaccine Research, Biological and Biomedical Sciences, Bandar Sunway, Malaysia
| | - Rozeena Baig
- Department of Biological and Biomedical Sciences, Aga Khan University, Karachi, Pakistan
| | - Mehdia Nadeem
- Department of Biological and Biomedical Sciences, Aga Khan University, Karachi, Pakistan
| | - Noor Akbar
- Department of Biology, Chemistry and Environmental Sciences, College of Arts and Sciences, American University of Sharjah, Sharjah, United Arab Emirates
| | - Fizza Nazim
- Department of Biological and Biomedical Sciences, Aga Khan University, Karachi, Pakistan
| | - Areeba Khaleeq
- Department of Biological and Biomedical Sciences, Aga Khan University, Karachi, Pakistan
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Rawat A, Singh P, Jyoti A, Kaushik S, Srivastava VK. Averting transmission: A pivotal target to manage amoebiasis. Chem Biol Drug Des 2020; 96:731-744. [PMID: 32356312 DOI: 10.1111/cbdd.13699] [Citation(s) in RCA: 9] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/03/2020] [Revised: 04/16/2020] [Accepted: 04/19/2020] [Indexed: 12/18/2022]
Abstract
Amoebiasis is a parasitic infectious disease caused by the enteric protozoan Entamoeba histolytica, a leading basis of deaths accounted to parasites, succeeding malaria and schistosomiasis. Conventional treatment methodologies used to deal with amoebiasis mainly rely on the administration of anti-amoebic compounds and vaccines but are often linked with substantial side-effects on the patient. Besides, cases of development of drug resistance in protozoans have been recorded, contributing further to the reduction in the efficiency of the treatment. Loopholes in the efficacious management of the disease call for the development of novel methodologies to manage amoebiasis. A way to achieve this is by targeting the essential metabolic processes of 'encystation' and 'excystation', and the associated biomolecules, thus interrupting the biphasic life cycle of the parasite. Technologies like the CRISPR-Cas9 system can efficiently be exploited to discover novel and essential molecules that regulate the protozoan's metabolism, while efficiently manipulating and managing the known drug targets, leading to an effective halt and forestall to the enteric infection. This review presents a perspective on these essential metabolic processes and the associated molecules that can be targeted efficaciously to prevent the transmission of amoebiasis, thus managing the disease and proving to be a fruitful endeavour.
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Affiliation(s)
- Aadish Rawat
- Amity Institute of Biotechnology, Amity University Rajasthan, Jaipur, India
| | - Parikshit Singh
- Amity Institute of Biotechnology, Amity University Rajasthan, Jaipur, India
| | - Anupam Jyoti
- Amity Institute of Biotechnology, Amity University Rajasthan, Jaipur, India
| | - Sanket Kaushik
- Amity Institute of Biotechnology, Amity University Rajasthan, Jaipur, India
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35
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Beri D, Yadav P, Devi HRN, Narayana C, Gadara D, Tatu U. Demonstration and Characterization of Cyst-Like Structures in the Life Cycle of Trichomonas vaginalis. Front Cell Infect Microbiol 2020; 9:430. [PMID: 32010634 PMCID: PMC6972724 DOI: 10.3389/fcimb.2019.00430] [Citation(s) in RCA: 12] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/03/2019] [Accepted: 12/02/2019] [Indexed: 12/14/2022] Open
Abstract
Trichomonas vaginalis is the parasitic protozoan residing in human urogenital tract causing trichomoniasis, which is the leading non-viral sexually transmitted disease. It has cosmopolitan distribution throughout the globe and affects both men and women. Lifecycle of the parasite has been traditionally described as consisting of motile and symptom-causing trophozoites. Chemical and temperature perturbations in trophozoites have been shown to aid conversion to pseudocysts, which is poorly investigated. In the current study, we show the formation of viable cyst-like structures (CLS) in stationary phase of T. vaginalis axenic culture. We used a fluorescent stain called calcofluor white, which specifically binds to chitin and cellulose-containing structures, to score for T. vaginalis CLS. Using flow cytometry, we demonstrated and quantitated the processes of encystation as well as excystation; thus, completing the parasite's lifecycle in vitro without any chemical/temperature alterations. Like cysts from other protozoan parasites such as Entamoeba histolytica and Giardia lamblia, T. vaginalis CLS appeared spherical, immotile, and resistant to osmotic lysis and detergent treatments. Ultrastructure of CLS demonstrated by Transmission Electron Microscopy showed a thick electron-dense deposition along its outer membrane. To probe the physiological role of CLS, we exposed parasites to vaginal pH and observed that trophozoites took this as a cue to convert to CLS. Further, upon co- culturing with cells of cervical origin, CLS rapidly excysted to form trophozoites which abrogated the cervical cell monolayer in a dose-dependent manner. To further corroborate the presence of two distinct forms in T. vaginalis, we performed two-dimensional gel electrophoresis and global, untargeted mass spectrometry to highlight differences in the proteome with trophozoites. Interestingly, CLS remained viable in chlorinated swimming pool water implicating the possibility of its role as environmentally resistant structures involved in non-sexual mode of parasite transmission. Finally, we showed that symptomatic human patient vaginal swabs had both T. vaginalis trophozoites and CLS; thus, highlighting its importance in clinical infections. Overall, our study highlights the plasticity of the pathogen and its rapid adaption when subjected to stressful environmental cues and suggests an important role of CLS in the parasite's life cycle, pathogenesis and transmission.
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Affiliation(s)
- Divya Beri
- Department of Biochemistry, Indian Institute of Science, Bangalore, India
| | - Priya Yadav
- Department of Biochemistry, Indian Institute of Science, Bangalore, India
| | | | - Chinmaya Narayana
- Department of Biochemistry, Indian Institute of Science, Bangalore, India
| | - Darshak Gadara
- Department of Biochemistry, Indian Institute of Science, Bangalore, India
| | - Utpal Tatu
- Department of Biochemistry, Indian Institute of Science, Bangalore, India
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Mi-Ichi F, Yoshida H. Unique Features of Entamoeba Sulfur Metabolism; Compartmentalization, Physiological Roles of Terminal Products, Evolution and Pharmaceutical Exploitation. Int J Mol Sci 2019; 20:ijms20194679. [PMID: 31546588 PMCID: PMC6801973 DOI: 10.3390/ijms20194679] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/30/2019] [Revised: 09/18/2019] [Accepted: 09/19/2019] [Indexed: 11/16/2022] Open
Abstract
Sulfur metabolism is essential for all living organisms. Recently, unique features of the Entamoeba metabolic pathway for sulfated biomolecules have been described. Entamoeba is a genus in the phylum Amoebozoa and includes the causative agent for amoebiasis, a global public health problem. This review gives an overview of the general features of the synthesis and degradation of sulfated biomolecules, and then highlights the characteristics that are unique to Entamoeba. Future biological and pharmaceutical perspectives are also discussed.
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Affiliation(s)
- Fumika Mi-Ichi
- Division of Molecular and Cellular Immunoscience, Department of Biomolecular Sciences, Faculty of Medicine, Saga University, 5-1-1 Nabeshima, Saga 849-8501, Japan.
| | - Hiroki Yoshida
- Division of Molecular and Cellular Immunoscience, Department of Biomolecular Sciences, Faculty of Medicine, Saga University, 5-1-1 Nabeshima, Saga 849-8501, Japan.
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Naiyer S, Bhattacharya A, Bhattacharya S. Advances in Entamoeba histolytica Biology Through Transcriptomic Analysis. Front Microbiol 2019; 10:1921. [PMID: 31481949 PMCID: PMC6710346 DOI: 10.3389/fmicb.2019.01921] [Citation(s) in RCA: 13] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/15/2019] [Accepted: 08/05/2019] [Indexed: 12/13/2022] Open
Abstract
A large number of transcriptome-level studies in Entamoeba histolytica, the protozoan parasite that causes amoebiasis, have investigated gene expression patterns to help understand the pathology and biology of the organism. They have compared virulent and avirulent strains in lab culture and after tissue invasion, cells grown under different stress conditions, response to anti-amoebic drug treatments, and gene expression changes during the process of encystation. These studies have revealed interesting molecules/pathways that will help increase our mechanistic understanding of differentially expressed genes during growth perturbations and tissue invasion. Some of the important insights obtained from transcriptome studies include the observations that regulation of carbohydrate metabolism may be an important determinant for tissue invasion, while the novel up-regulated genes during encystation include phospholipase D, and meiotic genes, suggesting the possibility of meiosis during the process. Classification of genes according to expression levels showed that amongst the highly transcribed genes in cultured E. histolytica trophozoites were some virulence factors, raising the question of the role of these factors in normal parasite growth. Promoter motifs associated with differential gene expression and regulation were identified. Some of these motifs associated with high gene expression were located downstream of start codon, and were required for efficient transcription. The listing of E. histolytica genes according to transcript expression levels will help us determine the scale of post-transcriptional regulation, and the possible roles of predicted promoter motifs. The small RNA transcriptome is a valuable resource for detailed structural and functional analysis of these molecules and their regulatory roles. These studies provide new drug targets and enhance our understanding of gene regulation in E. histolytica.
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Affiliation(s)
- Sarah Naiyer
- School of Environmental Sciences, Jawaharlal Nehru University, New Delhi, India
| | - Alok Bhattacharya
- School of Life Sciences, Jawaharlal Nehru University, New Delhi, India
| | - Sudha Bhattacharya
- School of Environmental Sciences, Jawaharlal Nehru University, New Delhi, India
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Duarte TT, Ellis CC, Grajeda BI, De Chatterjee A, Almeida IC, Das S. A Targeted Mass Spectrometric Analysis Reveals the Presence of a Reduced but Dynamic Sphingolipid Metabolic Pathway in an Ancient Protozoan, Giardia lamblia. Front Cell Infect Microbiol 2019; 9:245. [PMID: 31396488 PMCID: PMC6668603 DOI: 10.3389/fcimb.2019.00245] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/03/2019] [Accepted: 06/24/2019] [Indexed: 12/11/2022] Open
Abstract
Giardia lamblia, a single-celled eukaryote, colonizes and thrives in the small intestine of humans. Because of its compact and reduced genome, Giardia has adapted a “minimalistic” life style, as it becomes dependent on available resources of the small intestine. Because Giardia expresses fewer sphingolipid (SL) genes—and glycosphingolipids are critical for encystation—we investigated the SL metabolic cycle in this parasite. A tandem mass spectrometry (MS/MS) analysis reveals that major SLs in Giardia include sphingomyelins, sphingoid bases, ceramides, and glycosylceramides. Many of these lipids are obtained by Giardia from the growth medium, remodeled at their fatty acyl chains and end up in the spent medium. For instance, ceramide-1-phosphate, a proinflammatory molecule that is not present in the culture medium, is generated from sphingosine (abundant in the culture medium) possibly by remodeling reactions. It is then subsequently released into the spent medium. Thus, the secretion of ceramide-1-phospate and other SL derivatives by Giardia could be associated with inflammatory bowel disease observed in acute giardiasis. Additionally, we found that the levels of SLs increase in encysting Giardia and are differentially regulated throughout the encystation cycle. We propose that SL metabolism is important for this parasite and, could serve as potential targets for developing novel anti-giardial agents.
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Affiliation(s)
- Trevor T Duarte
- Department of Biological Sciences, Border Biomedical Research Center, University of Texas at El Paso, El Paso, TX, United States
| | - Cameron C Ellis
- Department of Biological Sciences, Border Biomedical Research Center, University of Texas at El Paso, El Paso, TX, United States
| | - Brian I Grajeda
- Department of Biological Sciences, Border Biomedical Research Center, University of Texas at El Paso, El Paso, TX, United States
| | - Atasi De Chatterjee
- Department of Biological Sciences, Border Biomedical Research Center, University of Texas at El Paso, El Paso, TX, United States
| | - Igor C Almeida
- Department of Biological Sciences, Border Biomedical Research Center, University of Texas at El Paso, El Paso, TX, United States.,Infectious Disease and Immunology Cluster, Border Biomedical Research Center, University of Texas at El Paso, El Paso, TX, United States
| | - Siddhartha Das
- Department of Biological Sciences, Border Biomedical Research Center, University of Texas at El Paso, El Paso, TX, United States.,Infectious Disease and Immunology Cluster, Border Biomedical Research Center, University of Texas at El Paso, El Paso, TX, United States
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Abstract
The human parasite Entamoeba histolytica is an important pathogen with significant global impact and is a leading cause of parasitic death in humans. Since only the cyst form can be transmitted, blocking encystation would prevent new infections, making the encystation pathway an attractive target for the development of new drugs. Identification of the genetic signals and transcriptional regulatory networks that control encystation would be an important advance in understanding the developmental cascade. We show that the Entamoeba NF-Y complex plays a crucial role in regulating the encystation process in Entamoeba. Nuclear factor Y (NF-Y) is a heterotrimeric transcription factor composed of three subunits, namely, NF-YA, NF-YB, and NF-YC, which are conserved throughout evolution. In higher eukaryotes, NF-Y plays important roles in several cellular processes (development, cell cycle regulation, apoptosis, and response to growth, stress, and DNA damage) by controlling gene expression through binding to a CCAAT promoter motif. We demonstrated that NF-Y subunits in the protist Entamoeba, while significantly divergent from those of higher eukaryotes, have well-conserved domains important for subunit interactions and DNA binding and that NF-YB and NF-YC are developmentally expressed during encystation. Electrophoretic mobility shift assays confirmed that the NF-Y protein(s) from Entamoeba cysts binds to a CCAAT motif. Consistent with a role as a transcription factor, the NF-Y proteins show nuclear localization during development. Additionally, we demonstrated that NF-YC localizes to the chromatoid body (an RNA processing center) during development, indicating that it may have a role in RNA processing. Finally, silencing of the NF-YC subunit resulted in reduced stability of the NF-Y complex and decreased encystation efficiency. We demonstrated that the NF-Y complex functions at a time point subsequent to the NAD+ flux and expression of the transcription factor encystation regulatory motif-binding protein, both of which are early regulators of Entamoeba development. Taken together, our results demonstrate that the NF-Y complex plays an important role in regulating encystation in Entamoeba and add to our understanding of the transcriptional networks and signals that control this essential developmental pathway in an important human pathogen.
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Hehmeyer J. Two potential evolutionary origins of the fruiting bodies of the dictyostelid slime moulds. Biol Rev Camb Philos Soc 2019; 94:1591-1604. [PMID: 30989827 DOI: 10.1111/brv.12516] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/03/2019] [Revised: 03/29/2019] [Accepted: 04/01/2019] [Indexed: 11/29/2022]
Abstract
Dictyostelium discoideum and the other dictyostelid slime moulds ('social amoebae') are popular model organisms best known for their demonstration of sorocarpic development. In this process, many cells aggregate to form a multicellular unit that ultimately becomes a fruiting body bearing asexual spores. Several other unrelated microorganisms undergo comparable processes, and in some it is evident that their multicellular development evolved from the differentiation process of encystation. While it has been argued that the dictyostelid fruiting body had similar origins, it has also been proposed that dictyostelid sorocarpy evolved from the unicellular fruiting process found in other amoebozoan slime moulds. This paper reviews the developmental biology of the dictyostelids and other relevant organisms and reassesses the two hypotheses on the evolutionary origins of dictyostelid development. Recent advances in phylogeny, genetics, and genomics and transcriptomics indicate that further research is necessary to determine whether or not the fruiting bodies of the dictyostelids and their closest relatives, the myxomycetes and protosporangids, are homologous.
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Manna D, Lentz CS, Ehrenkaufer GM, Suresh S, Bhat A, Singh U. An NAD +-dependent novel transcription factor controls stage conversion in Entamoeba. eLife 2018; 7:e37912. [PMID: 30375973 PMCID: PMC6207428 DOI: 10.7554/elife.37912] [Citation(s) in RCA: 17] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/26/2018] [Accepted: 10/17/2018] [Indexed: 12/22/2022] Open
Abstract
Developmental switching between life-cycle stages is a common feature among parasitic pathogens to facilitate disease transmission and pathogenesis. The protozoan parasite Entamoeba switches between invasive trophozoites and dormant cysts, but the encystation process remains poorly understood despite being central to amoebic biology. We identify a transcription factor, Encystation Regulatory Motif-Binding Protein (ERM-BP), that regulates encystation. Down-regulation of ERM-BP decreases encystation efficiency resulting in abnormal cysts with defective cyst walls. We demonstrate that direct binding of NAD+ to ERM-BP affects ERM-BP conformation and facilitates its binding to promoter DNA. Additionally, cellular NAD+ levels increase during encystation and exogenous NAD+ enhances encystation consistent with the role of carbon source depletion in triggering Entamoeba encystation. Furthermore, ERM-BP catalyzes conversion of nicotinamide to nicotinic acid, which might have second messenger effects on stage conversion. Our findings link the metabolic cofactors nicotinamide and NAD+ to transcriptional regulation via ERM-BP and provide the first mechanistic insights into Entamoeba encystation.
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Affiliation(s)
- Dipak Manna
- Division of Infectious Diseases, Department of Internal MedicineStanford University School of MedicineStanfordUnited States
| | | | - Gretchen Marie Ehrenkaufer
- Division of Infectious Diseases, Department of Internal MedicineStanford University School of MedicineStanfordUnited States
| | - Susmitha Suresh
- Division of Infectious Diseases, Department of Internal MedicineStanford University School of MedicineStanfordUnited States
| | - Amrita Bhat
- Division of Infectious Diseases, Department of Internal MedicineStanford University School of MedicineStanfordUnited States
| | - Upinder Singh
- Division of Infectious Diseases, Department of Internal MedicineStanford University School of MedicineStanfordUnited States
- Department of Microbiology and ImmunologyStanford University School of MedicineStanfordUnited States
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Mi-Ichi F, Miyake Y, Tam VK, Yoshida H. A Flow Cytometry Method for Dissecting the Cell Differentiation Process of Entamoeba Encystation. Front Cell Infect Microbiol 2018; 8:250. [PMID: 30087858 PMCID: PMC6066566 DOI: 10.3389/fcimb.2018.00250] [Citation(s) in RCA: 12] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/19/2018] [Accepted: 07/02/2018] [Indexed: 12/24/2022] Open
Abstract
Amoebiasis is caused by Entamoeba histolytica infection, a protozoan parasite belonging to the phylum Amoebozoa. This parasite undergoes a fundamental cell differentiation process from proliferative trophozoite to dormant cyst, termed “encystation.” The cysts formed by encystation are solely responsible for the transmission of amoebiasis; therefore, Entamoeba encystation is an important subject from both biological and medical perspectives. Here, we have established a flow cytometry strategy for not only determining the percentage of formed cysts but also for monitoring changes in cell populations during encystation. This strategy together with fluorescence microscopy enables visualization of the cell differentiation process of Entamoeba encystation. We also standardized another flow cytometry protocol for counting live trophozoites. These two different flow cytometry techniques could be integrated into 96-well plate-based bioassays for monitoring the processes of cyst formation and trophozoite proliferation, which are crucial to maintain the Entamoeba life cycle. The combined two systems enabled us to screen a chemical library, the Pathogen Box of the Medicine for Malaria Venture, to obtain compounds that inhibit either the formation of cysts or the proliferation of trophozoites, or both. This is a prerequisite for the development of new drugs against amoebiasis, a global public health problem. Collectively, the two different 96-well plate-based Entamoeba bioassay and flow cytometry analysis systems (cyst formation and trophozoite proliferation) provide a methodology that can not only overcome the limitations of standard microscopic counting but also is effective in applied as well as basic Entamoeba biology.
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Affiliation(s)
- Fumika Mi-Ichi
- Division of Molecular and Cellular Immunoscience, Department of Biomolecular Sciences, Faculty of Medicine, Saga University, Saga, Japan
| | - Yasunobu Miyake
- Division of Molecular and Cellular Immunoscience, Department of Biomolecular Sciences, Faculty of Medicine, Saga University, Saga, Japan
| | - Vo Kha Tam
- Division of Molecular and Cellular Immunoscience, Department of Biomolecular Sciences, Faculty of Medicine, Saga University, Saga, Japan
| | - Hiroki Yoshida
- Division of Molecular and Cellular Immunoscience, Department of Biomolecular Sciences, Faculty of Medicine, Saga University, Saga, Japan
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Sohn HJ, Kang H, Seo GE, Kim JH, Jung SY, Shin HJ. Efficient Liquid Media for Encystation of Pathogenic Free-Living Amoebae. Korean J Parasitol 2017; 55:233-238. [PMID: 28719947 PMCID: PMC5523890 DOI: 10.3347/kjp.2017.55.3.233] [Citation(s) in RCA: 19] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 02/15/2017] [Revised: 04/04/2017] [Accepted: 04/10/2017] [Indexed: 11/23/2022]
Abstract
Pathogenic Naegleria fowleri, Acanthamoeba castellanii, and Acanthamoeba polyphaga, are distributed worldwide. They are causative agents of primary amoebic meningoencephalitis or acanthamoebic keratitis in humans, respectively. Trophozoites encyst in unfavorable environments, such as exhausted food supply and desiccation. Until recently, the method of N. fowleri encystation used solid non-nutrient agar medium supplemented with heat-inactivated Escherichia coli; however, for the amoebic encystment of Acanthamoeba spp., a defined, slightly modified liquid media is used. In this study, in order to generate pure N. fowleri cysts, a liquid encystment medium (buffer 1) modified from Page’s amoeba saline was applied for encystation of N. fowleri. N. fowleri cysts were well induced after 24 hr with the above defined liquid encystment medium (buffer 1). This was confirmed by observation of a high expression of differential mRNA of nfa1 and actin genes in trophozoites. Thus, this liquid medium can replace the earlier non-nutrient agar medium for obtaining pure N. fowleri cysts. In addition, for cyst formation of Acanthamoeba spp., buffer 2 (adjusted to pH 9.0) was the more efficient medium. To summarize, these liquid encystment media may be useful for further studies which require axenic and pure amoebic cysts.
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Affiliation(s)
- Hae-Jin Sohn
- Department of Microbiology, Ajou University School of Medicine, and Department of Biomedical Science, Graduate School of Ajou University, Suwon 16499, Korea
| | - Heekyoung Kang
- Department of Microbiology, Ajou University School of Medicine, and Department of Biomedical Science, Graduate School of Ajou University, Suwon 16499, Korea
| | - Ga-Eun Seo
- Department of Microbiology, Ajou University School of Medicine, and Department of Biomedical Science, Graduate School of Ajou University, Suwon 16499, Korea
| | - Jong-Hyun Kim
- Institute of Animal Medicine, College of Veterinary Medicine, Gyeongsang National University, Jinju 52828, Korea
| | - Suk-Yul Jung
- Department of Biomedical Laboratory Science, Molecular Diagnostics Research Institute, School of Health and Medicine, Namseoul University, Cheonan 31020, Korea
| | - Ho-Joon Shin
- Department of Microbiology, Ajou University School of Medicine, and Department of Biomedical Science, Graduate School of Ajou University, Suwon 16499, Korea
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Barash NR, Nosala C, Pham JK, McInally SG, Gourguechon S, McCarthy-Sinclair B, Dawson SC. Giardia Colonizes and Encysts in High-Density Foci in the Murine Small Intestine. mSphere 2017; 2:e00343-16. [PMID: 28656177 DOI: 10.1128/mSphere.00343-16] [Citation(s) in RCA: 31] [Impact Index Per Article: 4.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/27/2016] [Accepted: 04/21/2017] [Indexed: 01/28/2023] Open
Abstract
Giardia is a single-celled parasite causing significant diarrheal disease in several hundred million people worldwide. Due to limited access to the site of infection in the gastrointestinal tract, our understanding of the dynamics of Giardia infections in the host has remained limited and largely inferred from laboratory culture. To better understand Giardia physiology and colonization in the host, we developed imaging methods to quantify Giardia expressing bioluminescent physiological reporters in two relevant animal models. We discovered that parasites primarily colonize and encyst in the proximal small intestine in discrete, high-density foci. We also show that high parasite density contributes to encystation initiation. Giardia lamblia is a highly prevalent yet understudied protistan parasite causing significant diarrheal disease worldwide. Hosts ingest Giardia cysts from contaminated sources. In the gastrointestinal tract, cysts excyst to become motile trophozoites, colonizing and attaching to the gut epithelium. Trophozoites later differentiate into infectious cysts that are excreted and contaminate the environment. Due to the limited accessibility of the gut, the temporospatial dynamics of giardiasis in the host are largely inferred from laboratory culture and thus may not mirror Giardia physiology in the host. Here, we have developed bioluminescent imaging (BLI) to directly interrogate and quantify the in vivo temporospatial dynamics of Giardia infection, thereby providing an improved murine model to evaluate anti-Giardia drugs. Using BLI, we determined that parasites primarily colonize the proximal small intestine nonuniformly in high-density foci. By imaging encystation-specific bioreporters, we show that encystation initiates shortly after inoculation and continues throughout the duration of infection. Encystation also initiates in high-density foci in the proximal small intestine, and high density contributes to the initiation of encystation in laboratory culture. We suggest that these high-density in vivo foci of colonizing and encysting Giardia likely result in localized disruption to the epithelium. This more accurate visualization of giardiasis redefines the dynamics of the in vivo Giardia life cycle, paving the way for future mechanistic studies of density-dependent parasitic processes in the host. IMPORTANCEGiardia is a single-celled parasite causing significant diarrheal disease in several hundred million people worldwide. Due to limited access to the site of infection in the gastrointestinal tract, our understanding of the dynamics of Giardia infections in the host has remained limited and largely inferred from laboratory culture. To better understand Giardia physiology and colonization in the host, we developed imaging methods to quantify Giardia expressing bioluminescent physiological reporters in two relevant animal models. We discovered that parasites primarily colonize and encyst in the proximal small intestine in discrete, high-density foci. We also show that high parasite density contributes to encystation initiation.
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Pham JK, Nosala C, Scott EY, Nguyen KF, Hagen KD, Starcevich HN, Dawson SC. Transcriptomic Profiling of High-Density Giardia Foci Encysting in the Murine Proximal Intestine. Front Cell Infect Microbiol 2017; 7:227. [PMID: 28620589 PMCID: PMC5450421 DOI: 10.3389/fcimb.2017.00227] [Citation(s) in RCA: 32] [Impact Index Per Article: 4.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/08/2017] [Accepted: 05/16/2017] [Indexed: 12/15/2022] Open
Abstract
Giardia is a highly prevalent, understudied protistan parasite causing significant diarrheal disease worldwide. Its life cycle consists of two stages: infectious cysts ingested from contaminated food or water sources, and motile trophozoites that colonize and attach to the gut epithelium, later encysting to form new cysts that are excreted into the environment. Current understanding of parasite physiology in the host is largely inferred from transcriptomic studies using Giardia grown axenically or in co-culture with mammalian cell lines. The dearth of information about the diversity of host-parasite interactions occurring within distinct regions of the gastrointestinal tract has been exacerbated by a lack of methods to directly and non-invasively interrogate disease progression and parasite physiology in live animal hosts. By visualizing Giardia infections in the mouse gastrointestinal tract using bioluminescent imaging (BLI) of tagged parasites, we recently showed that parasites colonize the gut in high-density foci. Encystation is initiated in these foci throughout the entire course of infection, yet how the physiology of parasites within high-density foci in the host gut differs from that of cells in laboratory culture is unclear. Here we use BLI to precisely select parasite samples from high-density foci in the proximal intestine to interrogate in vivo Giardia gene expression in the host. Relative to axenic culture, we noted significantly higher expression (>10-fold) of oxidative stress, membrane transporter, and metabolic and structural genes associated with encystation in the high-density foci. These differences in gene expression within parasite foci in the host may reflect physiological changes associated with high-density growth in localized regions of the gut. We also identified and verified six novel cyst-specific proteins, including new components of the cyst wall that were highly expressed in these foci. Our in vivo transcriptome data support an emerging view that parasites encyst early in localized regions in the gut, possibly as a consequence of nutrient limitation, and also impact local metabolism and physiology.
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Affiliation(s)
- Jonathan K Pham
- Department of Microbiology and Molecular Genetics, University of California, DavisDavis, CA, United States
| | - Christopher Nosala
- Department of Microbiology and Molecular Genetics, University of California, DavisDavis, CA, United States
| | - Erica Y Scott
- Department of Animal Science, University of California, DavisDavis, CA, United States
| | - Kristofer F Nguyen
- Department of Microbiology and Molecular Genetics, University of California, DavisDavis, CA, United States
| | - Kari D Hagen
- Department of Microbiology and Molecular Genetics, University of California, DavisDavis, CA, United States
| | - Hannah N Starcevich
- Department of Microbiology and Molecular Genetics, University of California, DavisDavis, CA, United States
| | - Scott C Dawson
- Department of Microbiology and Molecular Genetics, University of California, DavisDavis, CA, United States
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Moon EK, Hong Y, Lee HA, Quan FS, Kong HH. DNA Methylation of Gene Expression in Acanthamoeba castellanii Encystation. Korean J Parasitol 2017; 55:115-120. [PMID: 28506032 PMCID: PMC5450953 DOI: 10.3347/kjp.2017.55.2.115] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 02/21/2017] [Revised: 03/13/2017] [Accepted: 04/03/2017] [Indexed: 12/04/2022]
Abstract
Encystation mediating cyst specific cysteine proteinase (CSCP) of Acanthamoeba castellanii is expressed remarkably during encystation. However, the molecular mechanism involved in the regulation of CSCP gene expression remains unclear. In this study, we focused on epigenetic regulation of gene expression during encystation of Acanthamoeba. To evaluate methylation as a potential mechanism involved in the regulation of CSCP expression, we first investigated the correlation between promoter methylation status of CSCP gene and its expression. A 2,878 bp of promoter sequence of CSCP gene was amplified by PCR. Three CpG islands (island 1–3) were detected in this sequence using bioinformatics tools. Methylation of CpG island in trophozoites and cysts was measured by bisulfite sequence PCR. CSCP promoter methylation of CpG island 1 (1,633 bp) was found in 8.2% of trophozoites and 7.3% of cysts. Methylation of CpG island 2 (625 bp) was observed in 4.2% of trophozoites and 5.8% of cysts. Methylation of CpG island 3 (367 bp) in trophozoites and cysts was both 3.6%. These results suggest that DNA methylation system is present in CSCP gene expression of Acanthamoeba. In addition, the expression of encystation mediating CSCP is correlated with promoter CpG island 1 hypomethylation.
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Affiliation(s)
- Eun-Kyung Moon
- Department of Medical Zoology, Kyung Hee University School of Medicine, Seoul 02447, Korea
| | - Yeonchul Hong
- Department of Parasitology and Tropical Medicine, Kyungpook National University School of Medicine, Daegu 41944, Korea
| | - Hae-Ahm Lee
- Department of Pharmacology, Kyungpook National University School of Medicine, Daegu 41944, Korea
| | - Fu-Shi Quan
- Department of Medical Zoology, Kyung Hee University School of Medicine, Seoul 02447, Korea
| | - Hyun-Hee Kong
- Department of Parasitology, Dong-A University College of Medicine, Busan 49201, Korea
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Moon EK, Kong HH, Hong Y, Lee HA, Quan FS. Identification and Characterization of Protein Arginine Methyltransferase 1 in Acanthamoeba castellanii. Korean J Parasitol 2017; 55:109-114. [PMID: 28506031 PMCID: PMC5450952 DOI: 10.3347/kjp.2017.55.2.109] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 02/06/2017] [Revised: 04/05/2017] [Accepted: 04/08/2017] [Indexed: 01/19/2023]
Abstract
Protein arginine methyltransferase (PRMT) is an important epigenetic regulator in eukaryotic cells. During encystation, an essential process for Acanthamoeba survival, the expression of a lot of genes involved in the encystation process has to be regulated in order to be induced or inhibited. However, the regulation mechanism of these genes is yet unknown. In this study, the full-length 1,059 bp cDNA sequence of Acanthamoeba castellanii PRMT1 (AcPRMT1) was cloned for the first time. The AcPRMT1 protein comprised of 352 amino acids with a SAM-dependent methyltransferase PRMT-type domain. The expression level of AcPRMT1 was highly increased during encystation of A. castellanii. The EGFP-AcPRMT1 fusion protein was distributed over the cytoplasm, but it was mainly localized in the nucleus of Acanthamoeba. Knock down of AcPRMT1 by synthetic siRNA with a complementary sequence failed to form mature cysts. These findings suggested that AcPRMT1 plays a critical role in the regulation of encystation of A. castellanii. The target gene of AcPRMT1 regulation and the detailed mechanisms need to be investigated by further studies.
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Affiliation(s)
- Eun-Kyung Moon
- Department of Medical Zoology, Kyung Hee University School of Medicine, Seoul 02447, Korea
| | - Hyun-Hee Kong
- Department of Parasitology, Dong-A University College of Medicine, Busan 49201, Korea
| | - Yeonchul Hong
- Department of Parasitology and Tropical Medicine, Kyungpook National University School of Medicine, Daegu 41944, Korea
| | - Hae-Ahm Lee
- Department of Pharmacology, Kyungpook National University School of Medicine, Daegu 41944, Korea
| | - Fu-Shi Quan
- Department of Medical Zoology, Kyung Hee University School of Medicine, Seoul 02447, Korea
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Herrera-Martínez M, Hernández-Ramírez VI, Hernández-Carlos B, Chávez-Munguía B, Calderón-Oropeza MA, Talamás-Rohana P. Antiamoebic Activity of Adenophyllum aurantium (L.) Strother and Its Effect on the Actin Cytoskeleton of Entamoeba histolytica. Front Pharmacol 2016; 7:169. [PMID: 27445810 PMCID: PMC4922267 DOI: 10.3389/fphar.2016.00169] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/07/2016] [Accepted: 06/03/2016] [Indexed: 11/13/2022] Open
Abstract
In Mexico, the Adenophyllum aurantium (L.) Strother plant is consumed as an infusion to treat intestinal diseases such as amoebiasis, which is an endemic health problem in Mexico and other countries. However, the effect of A. aurantium on Entamoeba histolytica, the causative agent of amoebiasis, is unknown. An aerial part methanolic extract (AaMeA), a root methanolic extract (AaMeR) and a root ethyl acetate extract (AaEaR) were tested on E. histolytica trophozoites. AaMeA and AaMeR did not show antiproliferative activity; however, AaEaR exhibited an in vitro GI50 of 230 μg/ml, and it was able to inhibit the differentiation of Entamoeba invadens trophozoites into cysts. The intraperitoneal administration of AaEaR (2.5 or 5 mg) to hamsters that were infected with E. histolytica inhibited the development of amoebic liver abscesses in 48.5 or 89.0% of the animals, respectively. Adhesion to fibronectin and erythrophagocytosis were 28.7 and 37.5% inhibited by AaEaR, respectively. An ultrastructure analysis of AaEaR-treated trophozoites shows a decrease in the number of vacuoles but no apparent cell damage. Moreover, this extract affected the actin cytoskeleton structuration, and it prevented the formation of contractile rings by mechanism(s) that were independent of reactive oxygen species and RhoA activation pathways. (13)C NMR data showed that the major compounds in the AaEaR extract are thiophenes. Our results suggest that AaEaR may be effective in treatments against amoebiasis, nevertheless, detailed toxicity studies on thiophenes, contained in AaEaR, are required to avoid misuse of this vegetal species.
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Affiliation(s)
- Mayra Herrera-Martínez
- Departamento de Infectómica y Patogénesis Molecular, Centro de Investigación y de Estudios Avanzados del Instituto Politécnico NacionalCiudad de México, Mexico
| | - Verónica I. Hernández-Ramírez
- Departamento de Infectómica y Patogénesis Molecular, Centro de Investigación y de Estudios Avanzados del Instituto Politécnico NacionalCiudad de México, Mexico
| | | | - Bibiana Chávez-Munguía
- Departamento de Infectómica y Patogénesis Molecular, Centro de Investigación y de Estudios Avanzados del Instituto Politécnico NacionalCiudad de México, Mexico
| | | | - Patricia Talamás-Rohana
- Departamento de Infectómica y Patogénesis Molecular, Centro de Investigación y de Estudios Avanzados del Instituto Politécnico NacionalCiudad de México, Mexico
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Moon EK, Hong Y, Chung DI, Goo YK, Kong HH. Identification of Protein Arginine Methyltransferase 5 as a Regulator for Encystation of Acanthamoeba. Korean J Parasitol 2016; 54:133-8. [PMID: 27180570 PMCID: PMC4870982 DOI: 10.3347/kjp.2016.54.2.133] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 09/14/2015] [Revised: 12/10/2015] [Accepted: 12/29/2015] [Indexed: 11/23/2022]
Abstract
Encystation is an essential process for Acanthamoeba survival under nutrient-limiting conditions and exposure to drugs. The expression of several genes has been observed to increase or decrease during encystation. Epigenetic processes involved in regulation of gene expression have been shown to play a role in several pathogenic parasites. In the present study, we identified the protein arginine methyltransferase 5 (PRMT5), a known epigenetic regulator, in Acanthamoeba castellanii. PRMT5 of A. castellanii (AcPRMT5) contained domains found in S-adenosylmethionine-dependent methyltransferases and in PRMT5 arginine-N-methyltransferase. Expression levels of AcPRMT5 were increased during encystation of A. castellanii. The EGFP-PRMT5 fusion protein was mainly localized in the nucleus of trophozoites. A. castellanii transfected with siRNA designed against AcPRMT5 failed to form mature cysts. The findings of this study lead to a better understanding of epigenetic mechanisms behind the regulation of encystation in cyst-forming pathogenic protozoa.
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Affiliation(s)
- Eun-Kyung Moon
- Department of Medical Zoology, Kyung Hee University School of Medicine, Seoul 02447, Korea
| | - Yeonchul Hong
- Department of Parasitology and Tropical Medicine, Kyungpook National University School of Medicine, Daegu 41944, Korea
| | - Dong-Il Chung
- Department of Parasitology and Tropical Medicine, Kyungpook National University School of Medicine, Daegu 41944, Korea
| | - Youn-Kyoung Goo
- Department of Parasitology and Tropical Medicine, Kyungpook National University School of Medicine, Daegu 41944, Korea
| | - Hyun-Hee Kong
- Department of Parasitology, Dong-A University College of Medicine, Busan 49201, Korea
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50
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Abstract
Enteric protozoan Entamoeba histolytica is a major cause of debilitating diarrheal infection worldwide with high morbidity and mortality. Even though the clinical burden of this parasite is very high, this infection is categorized as a neglected disease. Parasite is transmitted through feco-oral route and exhibit two distinct stages namely – trophozoites and cysts. Mechanism and regulation of encystation is not clearly understood. Previous studies have established the role of Heat shock protein 90 (Hsp90) in regulating stage transition in various protozoan parasites like Giardia, Plasmodium, Leishmania, and Toxoplasma. Our study for the first time reports that Hsp90 plays a crucial role in life cycle of Entamoeba as well. We identify Hsp90 to be a negative regulator of encystation in Entamoeba. We also show that Hsp90 inhibition interferes with the process of phagocytosis in Entamoeba. Overall, we show that Hsp90 plays an important role in virulence and transmission of Entamoeba.
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Affiliation(s)
- Meetali Singh
- Department of Biochemistry, Indian Institute of Science Bangalore, India
| | - Shalini Sharma
- School of Life Sciences, Jawaharlal Nehru University New Delhi, India
| | - Alok Bhattacharya
- School of Life Sciences, Jawaharlal Nehru University New Delhi, India
| | - Utpal Tatu
- Department of Biochemistry, Indian Institute of Science Bangalore, India
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