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Ungogo MA, de Koning HP. Drug resistance in animal trypanosomiases: Epidemiology, mechanisms and control strategies. Int J Parasitol Drugs Drug Resist 2024; 25:100533. [PMID: 38555795 PMCID: PMC10990905 DOI: 10.1016/j.ijpddr.2024.100533] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/18/2023] [Revised: 03/13/2024] [Accepted: 03/15/2024] [Indexed: 04/02/2024]
Abstract
Animal trypanosomiasis (AT) is a complex of veterinary diseases known under various names such as nagana, surra, dourine and mal de caderas, depending on the country, the infecting trypanosome species and the host. AT is caused by parasites of the genus Trypanosoma, and the main species infecting domesticated animals are T. brucei brucei, T. b. rhodesiense, T. congolense, T. simiae, T. vivax, T. evansi and T. equiperdum. AT transmission, again depending on species, is through tsetse flies or common Stomoxys and tabanid flies or through copulation. Therefore, the geographical spread of all forms of AT together is not restricted to the habitat of a single vector like the tsetse fly and currently includes almost all of Africa, and most of South America and Asia. The disease is a threat to millions of companion and farm animals in these regions, creating a financial burden in the billions of dollars to developing economies as well as serious impacts on livestock rearing and food production. Despite the scale of these impacts, control of AT is neglected and under-resourced, with diagnosis and treatments being woefully inadequate and not improving for decades. As a result, neither the incidence of the disease, nor the effectiveness of treatment is documented in most endemic countries, although it is clear that there are serious issues of resistance to the few old drugs that are available. In this review we particularly look at the drugs, their application to the various forms of AT, and their mechanisms of action and resistance. We also discuss the spread of veterinary trypanocide resistance and its drivers, and highlight current and future strategies to combat it.
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Affiliation(s)
- Marzuq A Ungogo
- The Roslin Institute, Royal (Dick) School of Veterinary Studies, University of Edinburgh, Edinburgh, United Kingdom; School of Infection and Immunity, College of Medical, Veterinary and Life Sciences, University of Glasgow, Glasgow, United Kingdom
| | - Harry P de Koning
- School of Infection and Immunity, College of Medical, Veterinary and Life Sciences, University of Glasgow, Glasgow, United Kingdom.
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2
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Urbaniak MD, Gadelha C. A transferrin receptor's guide to African trypanosomes. Cell Surf 2023; 9:100100. [PMID: 37396714 PMCID: PMC10311239 DOI: 10.1016/j.tcsw.2023.100100] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/05/2023] [Revised: 01/25/2023] [Accepted: 01/25/2023] [Indexed: 01/29/2023] Open
Affiliation(s)
- Michael D. Urbaniak
- Division of Biomedical and Life Sciences, Faculty of Health and Medicine, Lancaster University, Lancaster LA1 4YG, United Kingdom
| | - Catarina Gadelha
- School of Life Sciences, University of Nottingham, Nottingham NG7 2UH, United Kingdom
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3
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Albisetti A, Hälg S, Zoltner M, Mäser P, Wiedemar N. Suramin action in African trypanosomes involves a RuvB-like DNA helicase. Int J Parasitol Drugs Drug Resist 2023; 23:44-53. [PMID: 37757728 PMCID: PMC10520940 DOI: 10.1016/j.ijpddr.2023.09.003] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/04/2023] [Revised: 09/15/2023] [Accepted: 09/19/2023] [Indexed: 09/29/2023]
Abstract
Suramin is one of the oldest drugs in use today. It is still the treatment of choice for the hemolymphatic stage of African sleeping sickness caused by Trypanosoma brucei rhodesiense, and it is also used for surra in camels caused by Trypanosoma evansi. Yet despite one hundred years of use, suramin's mode of action is not fully understood. Suramin is a polypharmacological molecule that inhibits diverse proteins. Here we demonstrate that a DNA helicase of the pontin/ruvB-like 1 family, termed T. brucei RuvBL1, is involved in suramin resistance in African trypanosomes. Bloodstream-form T. b. rhodesiense under long-term selection for suramin resistance acquired a homozygous point mutation, isoleucine-312 to valine, close to the ATP binding site of T. brucei RuvBL1. The introduction of this missense mutation, by reverse genetics, into drug-sensitive trypanosomes significantly decreased their sensitivity to suramin. Intriguingly, the corresponding residue of T. evansi RuvBL1 was found mutated in a suramin-resistant field isolate, in that case to a leucine. RuvBL1 (Tb927.4.1270) is predicted to build a heterohexameric complex with RuvBL2 (Tb927.4.2000). RNAi-mediated silencing of gene expression of either T. brucei RuvBL1 or RuvBL2 caused cell death within 72 h. At 36 h after induction of RNAi, bloodstream-form trypanosomes exhibited a cytokinesis defect resulting in the accumulation of cells with two nuclei and two or more kinetoplasts. Taken together, these data indicate that RuvBL1 DNA helicase is involved in suramin action in African trypanosomes.
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Affiliation(s)
- Anna Albisetti
- Swiss Tropical and Public Health Institute, Kreuzstrasse 2, 4123, Allschwil, Switzerland; University of Basel, Petersplatz 1, 4001, Basel, Switzerland
| | - Silvan Hälg
- Swiss Tropical and Public Health Institute, Kreuzstrasse 2, 4123, Allschwil, Switzerland; University of Basel, Petersplatz 1, 4001, Basel, Switzerland
| | - Martin Zoltner
- Department of Parasitology, Faculty of Science, Charles University in Prague, Biocev, Vestec, Czech Republic
| | - Pascal Mäser
- Swiss Tropical and Public Health Institute, Kreuzstrasse 2, 4123, Allschwil, Switzerland; University of Basel, Petersplatz 1, 4001, Basel, Switzerland
| | - Natalie Wiedemar
- Swiss Tropical and Public Health Institute, Kreuzstrasse 2, 4123, Allschwil, Switzerland; University of Basel, Petersplatz 1, 4001, Basel, Switzerland.
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Jamabo M, Mahlalela M, Edkins AL, Boshoff A. Tackling Sleeping Sickness: Current and Promising Therapeutics and Treatment Strategies. Int J Mol Sci 2023; 24:12529. [PMID: 37569903 PMCID: PMC10420020 DOI: 10.3390/ijms241512529] [Citation(s) in RCA: 2] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/13/2023] [Revised: 07/27/2023] [Accepted: 08/03/2023] [Indexed: 08/13/2023] Open
Abstract
Human African trypanosomiasis is a neglected tropical disease caused by the extracellular protozoan parasite Trypanosoma brucei, and targeted for eradication by 2030. The COVID-19 pandemic contributed to the lengthening of the proposed time frame for eliminating human African trypanosomiasis as control programs were interrupted. Armed with extensive antigenic variation and the depletion of the B cell population during an infectious cycle, attempts to develop a vaccine have remained unachievable. With the absence of a vaccine, control of the disease has relied heavily on intensive screening measures and the use of drugs. The chemotherapeutics previously available for disease management were plagued by issues such as toxicity, resistance, and difficulty in administration. The approval of the latest and first oral drug, fexinidazole, is a major chemotherapeutic achievement for the treatment of human African trypanosomiasis in the past few decades. Timely and accurate diagnosis is essential for effective treatment, while poor compliance and resistance remain outstanding challenges. Drug discovery is on-going, and herein we review the recent advances in anti-trypanosomal drug discovery, including novel potential drug targets. The numerous challenges associated with disease eradication will also be addressed.
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Affiliation(s)
- Miebaka Jamabo
- Biotechnology Innovation Centre, Rhodes University, Makhanda 6139, South Africa; (M.J.); (M.M.)
| | - Maduma Mahlalela
- Biotechnology Innovation Centre, Rhodes University, Makhanda 6139, South Africa; (M.J.); (M.M.)
| | - Adrienne L. Edkins
- Department of Biochemistry and Microbiology, Biomedical Biotechnology Research Centre (BioBRU), Rhodes University, Makhanda 6139, South Africa;
| | - Aileen Boshoff
- Biotechnology Innovation Centre, Rhodes University, Makhanda 6139, South Africa; (M.J.); (M.M.)
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Makarov A, Began J, Mautone IC, Pinto E, Ferguson L, Zoltner M, Zoll S, Field MC. The role of invariant surface glycoprotein 75 in xenobiotic acquisition by African trypanosomes. MICROBIAL CELL (GRAZ, AUSTRIA) 2023; 10:18-35. [PMID: 36789350 PMCID: PMC9896412 DOI: 10.15698/mic2023.02.790] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 08/19/2022] [Revised: 01/02/2023] [Accepted: 01/13/2023] [Indexed: 02/05/2023]
Abstract
The surface proteins of parasitic protozoa mediate functions essential to survival within a host, including nutrient accumulation, environmental sensing and immune evasion. Several receptors involved in nutrient uptake and defence from the innate immune response have been described in African trypanosomes and, together with antigenic variation, contribute towards persistence within vertebrate hosts. Significantly, a superfamily of invariant surface glycoproteins (ISGs) populates the trypanosome surface, one of which, ISG75, is implicated in uptake of the century-old drug suramin. By CRISPR/Cas9 knockout and biophysical analysis, we show here that ISG75 directly binds suramin and mediates uptake of additional naphthol-related compounds, making ISG75 a conduit for entry of at least one structural class of trypanocidal compounds. However, ISG75 null cells present only modest attenuation of suramin sensitivity, have unaltered viability in vivo and in vitro and no alteration to suramin-invoked proteome responses. While ISG75 is demonstrated as a valid suramin cell entry pathway, we suggest the presence of additional mechanisms for suramin accumulation, further demonstrating the complexity of trypanosomatid drug interactions and potential for evolution of resistance.
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Affiliation(s)
- Alexandr Makarov
- School of Life Sciences, University of Dundee, Dundee, DD1 5EH, UK
| | - Jakub Began
- Laboratory of Structural Parasitology, Institute of Organic Chemistry and Biochemistry, Czech Academy of Sciences, 16610 Prague 6, Czech Republic
| | - Ileana Corvo Mautone
- School of Life Sciences, University of Dundee, Dundee, DD1 5EH, UK
- Laboratorio de Moléculas Bioactivas, Departamento de Ciencias Biológicas, Universidad de la República, Paysandú 60000, Uruguay
| | - Erika Pinto
- School of Life Sciences, University of Dundee, Dundee, DD1 5EH, UK
| | - Liam Ferguson
- School of Life Sciences, University of Dundee, Dundee, DD1 5EH, UK
| | - Martin Zoltner
- School of Life Sciences, University of Dundee, Dundee, DD1 5EH, UK
- Charles University, Faculty of Science, Department of Parasitology, Vestec, Czech Republic
| | - Sebastian Zoll
- Laboratory of Structural Parasitology, Institute of Organic Chemistry and Biochemistry, Czech Academy of Sciences, 16610 Prague 6, Czech Republic
| | - Mark C. Field
- School of Life Sciences, University of Dundee, Dundee, DD1 5EH, UK
- Institute of Parasitology, Biology Centre, Czech Academy of Sciences, 37005 Ceske Budejovice, Czech Republic
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Kasozi KI, MacLeod ET, Welburn SC. Systematic Review and Meta-Analysis on Human African Trypanocide Resistance. Pathogens 2022; 11:pathogens11101100. [PMID: 36297157 PMCID: PMC9612373 DOI: 10.3390/pathogens11101100] [Citation(s) in RCA: 6] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/24/2022] [Revised: 09/14/2022] [Accepted: 09/20/2022] [Indexed: 11/16/2022] Open
Abstract
Background Human African trypanocide resistance (HATr) is a challenge for the eradication of Human African Trypansomiaisis (HAT) following the widespread emergence of increased monotherapy drug treatment failures against Trypanosoma brucei gambiense and T. b. rhodesiense that are associated with changes in pathogen receptors. Methods: Electronic searches of 12 databases and 3 Google search websites for human African trypanocide resistance were performed using a keyword search criterion applied to both laboratory and clinical studies. Fifty-one publications were identified and included in this study using the PRISMA checklist. Data were analyzed using RevMan and random effect sizes were computed for the statistics at the 95% confidence interval. Results: Pentamidine/melarsoprol/nifurtimox cross-resistance is associated with loss of the T. brucei adenosine transporter 1/purine 2 gene (TbAT1/P2), aquaglyceroporins (TbAQP) 2 and 3, followed by the high affinity pentamidine melarsoprol transporter (HAPT) 1. In addition, the loss of the amino acid transporter (AAT) 6 is associated with eflornithine resistance. Nifurtimox/eflornithine combination therapy resistance is associated with AAT6 and nitroreductase loss, and high resistance and parasite regrowth is responsible for treatment relapse. In clinical studies, the TbAT1 proportion of total random effects was 68% (95% CI: 38.0−91.6); I2 = 96.99% (95% CI: 94.6−98.3). Treatment failure rates were highest with melarsoprol followed by eflornithine at 41.49% (95% CI: 24.94−59.09) and 6.56% (3.06−11.25) respectively. HATr-resistant phenotypes used in most laboratory experiments demonstrated significantly higher pentamidine resistance than other trypanocides. Conclusion: The emergence of drug resistance across the spectrum of trypanocidal agents that are used to treat HAT is a major threat to the global WHO target to eliminate HAT by 2030. T. brucei strains were largely resistant to diamidines and the use of high trypanocide concentrations in clinical studies have proved fatal in humans. Studies to develop novel chemotherapeutical agents and identify alternative protein targets could help to reduce the emergence and spread of HATr.
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Affiliation(s)
- Keneth Iceland Kasozi
- Infection Medicine, Deanery of Biomedical Sciences, Edinburgh Medical School, College of Medicine and Veterinary Medicine, The University of Edinburgh, Edinburgh EH8 9JZ, UK
- School of Medicine, Kabale University, Kabale P.O. Box 317, Uganda
- Correspondence: (K.I.K.); (S.C.W.)
| | - Ewan Thomas MacLeod
- Infection Medicine, Deanery of Biomedical Sciences, Edinburgh Medical School, College of Medicine and Veterinary Medicine, The University of Edinburgh, Edinburgh EH8 9JZ, UK
| | - Susan Christina Welburn
- Infection Medicine, Deanery of Biomedical Sciences, Edinburgh Medical School, College of Medicine and Veterinary Medicine, The University of Edinburgh, Edinburgh EH8 9JZ, UK
- Zhejiang University-University of Edinburgh Joint Institute, Zhejiang University, International Campus, 718 East Haizhou Road, Haining 314400, China
- Correspondence: (K.I.K.); (S.C.W.)
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Beilstein S, El Phil R, Sahraoui SS, Scapozza L, Kaiser M, Mäser P. Laboratory Selection of Trypanosomatid Pathogens for Drug Resistance. Pharmaceuticals (Basel) 2022; 15:ph15020135. [PMID: 35215248 PMCID: PMC8879015 DOI: 10.3390/ph15020135] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/23/2021] [Revised: 01/13/2022] [Accepted: 01/14/2022] [Indexed: 11/16/2022] Open
Abstract
The selection of parasites for drug resistance in the laboratory is an approach frequently used to investigate the mode of drug action, estimate the risk of emergence of drug resistance, or develop molecular markers for drug resistance. Here, we focused on the How rather than the Why of laboratory selection, discussing different experimental set-ups based on research examples with Trypanosoma brucei, Trypanosoma cruzi, and Leishmania spp. The trypanosomatids are particularly well-suited to illustrate different strategies of selecting for drug resistance, since it was with African trypanosomes that Paul Ehrlich performed such an experiment for the first time, more than a century ago. While breakthroughs in reverse genetics and genome editing have greatly facilitated the identification and validation of candidate resistance mutations in the trypanosomatids, the forward selection of drug-resistant mutants still relies on standard in vivo models and in vitro culture systems. Critical questions are: is selection for drug resistance performed in vivo or in vitro? With the mammalian or with the insect stages of the parasites? Under steady pressure or by sudden shock? Is a mutagen used? While there is no bona fide best approach, we think that a methodical consideration of these questions provides a helpful framework for selection of parasites for drug resistance in the laboratory.
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Affiliation(s)
- Sabina Beilstein
- Department Medical Parasitology and Infection Biology, Swiss Tropical and Public Health Institute, 4051 Basel, Switzerland; (S.B.); (M.K.)
- Swiss TPH, University of Basel, Petersplatz 1, 4002 Basel, Switzerland
| | - Radhia El Phil
- School of Pharmaceutical Sciences, University of Geneva, 1205 Geneva, Switzerland; (R.E.P.); (S.S.S.); (L.S.)
- Institute of Pharmaceutical Sciences of Western Switzerland, University of Geneva, 1211 Geneva, Switzerland
| | - Suzanne Sherihan Sahraoui
- School of Pharmaceutical Sciences, University of Geneva, 1205 Geneva, Switzerland; (R.E.P.); (S.S.S.); (L.S.)
- Institute of Pharmaceutical Sciences of Western Switzerland, University of Geneva, 1211 Geneva, Switzerland
| | - Leonardo Scapozza
- School of Pharmaceutical Sciences, University of Geneva, 1205 Geneva, Switzerland; (R.E.P.); (S.S.S.); (L.S.)
- Institute of Pharmaceutical Sciences of Western Switzerland, University of Geneva, 1211 Geneva, Switzerland
| | - Marcel Kaiser
- Department Medical Parasitology and Infection Biology, Swiss Tropical and Public Health Institute, 4051 Basel, Switzerland; (S.B.); (M.K.)
- Swiss TPH, University of Basel, Petersplatz 1, 4002 Basel, Switzerland
| | - Pascal Mäser
- Department Medical Parasitology and Infection Biology, Swiss Tropical and Public Health Institute, 4051 Basel, Switzerland; (S.B.); (M.K.)
- Swiss TPH, University of Basel, Petersplatz 1, 4002 Basel, Switzerland
- Correspondence: ; Tel.: +41-61-284-8338
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Silva Pereira S, Jackson AP, Figueiredo LM. Evolution of the variant surface glycoprotein family in African trypanosomes. Trends Parasitol 2021; 38:23-36. [PMID: 34376326 DOI: 10.1016/j.pt.2021.07.012] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/28/2021] [Revised: 07/21/2021] [Accepted: 07/22/2021] [Indexed: 01/22/2023]
Abstract
An intriguing and remarkable feature of African trypanosomes is their antigenic variation system, mediated by the variant surface glycoprotein (VSG) family and fundamental to both immune evasion and disease epidemiology within host populations. Recent studies have revealed that the VSG repertoire has a complex evolutionary history. Sequence diversity, genomic organization, and expression patterns are species-specific, which may explain other variations in parasite virulence and disease pathology. Evidence also shows that we may be underestimating the extent to what VSGs are repurposed beyond their roles as variant antigens, establishing a need to examine VSG functionality more deeply. Here, we review sequence variation within the VSG gene family, and highlight the many opportunities to explore their likely diverse contributions to parasite survival.
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Affiliation(s)
- Sara Silva Pereira
- Instituto de Medicina Molecular - João Lobo Antunes, Faculdade de Medicina, Universidade de Lisboa, Lisbon, Portugal
| | - Andrew P Jackson
- Institute of Infection, Veterinary and Ecological Sciences, University of Liverpool, Liverpool L3 5RF, UK
| | - Luísa M Figueiredo
- Instituto de Medicina Molecular - João Lobo Antunes, Faculdade de Medicina, Universidade de Lisboa, Lisbon, Portugal.
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Mutuku CN, Bateta R, Rono MK, Njunge JM, Awuoche EO, Ndung'u K, Mang'era CM, Akoth MO, Adung'a VO, Ondigo BN, Mireji PO. Physiological and proteomic profiles of Trypanosoma brucei rhodesiense parasite isolated from suramin responsive and non-responsive HAT patients in Busoga, Uganda. Int J Parasitol Drugs Drug Resist 2021; 15:57-67. [PMID: 33588295 PMCID: PMC7895675 DOI: 10.1016/j.ijpddr.2021.02.001] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/24/2020] [Revised: 02/02/2021] [Accepted: 02/02/2021] [Indexed: 11/17/2022]
Abstract
Human African Trypanosomiasis (HAT) is a disease of major economic importance in Sub-Saharan Africa. The HAT is caused by Trypanosoma brucei rhodesiense (Tbr) parasite in eastern and southern Africa, with suramin as drug of choice for treatment of early stage of the disease. Suramin treatment failures has been observed among HAT patients in Tbr foci in Uganda. In this study, we assessed Tbr parasite strains isolated from HAT patients responsive (Tbr EATRO-232) and non-responsive (Tbr EATRO-734) to suramin treatment in Busoga, Uganda for 1) putative role of suramin resistance in the treatment failure 2) correlation of suramin resistance with Tbr pathogenicity and 3) proteomic pathways underpinning the potential suramin resistance phenotype in vivo. We first assessed suramin response in each isolate by infecting male Swiss white mice followed by treatment using a series of suramin doses. We then assessed relative pathogenicity of the two Tbr isolates by assessing changes pathogenicity indices (prepatent period, survival and mortality). We finally isolated proteins from mice infected by the isolates, and assessed their proteomic profiles using mass spectrometry. We established putative resistance to 2.5 mg/kg suramin in the parasite Tbr EATRO-734. We established that Tbr EATRO-734 proliferated slower and has significantly enriched pathways associated with detoxification and metabolism of energy and drugs relative to Tbr EATRO-232. The Tbr EATRO-734 also has more abundantly expressed mitochondrion proteins and enzymes than Tbr EATRO-232. The suramin treatment failure may be linked to the relatively higher resistance to suramin in Tbr EATRO-734 than Tbr EATRO-232, among other host and parasite specific factors. However, the Tbr EATRO-734 appears to be less pathogenic than Tbr EATRO-232, as evidenced by its lower rate of parasitaemia. The Tbr EATRO-734 putatively surmount suramin challenges through induction of energy metabolism pathways. These cellular and molecular processes may be involved in suramin resistance in Tbr.
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Affiliation(s)
- Catherine N Mutuku
- Biotechnology Research Institute, Kenya Agricultural and Livestock Research Organization, P.O. Box 362, Kikuyu, Kenya; Department of Biochemistry and Molecular Biology, Egerton University, P.O. Box 536, Njoro, Kenya
| | - Rosemary Bateta
- Biotechnology Research Institute, Kenya Agricultural and Livestock Research Organization, P.O. Box 362, Kikuyu, Kenya.
| | - Martin K Rono
- Centre for Geographic Medicine Research - Coast, Kenya Medical Research Institute, PO Box 230-80108 Kilifi, Kenya
| | - James M Njunge
- Centre for Geographic Medicine Research - Coast, Kenya Medical Research Institute, PO Box 230-80108 Kilifi, Kenya
| | - Erick O Awuoche
- Department of Biological Sciences, School of Pure and Applied Science, Meru University of Science and Technology, Meru, Kenya
| | - Kariuki Ndung'u
- Biotechnology Research Institute, Kenya Agricultural and Livestock Research Organization, P.O. Box 362, Kikuyu, Kenya
| | - Clarence M Mang'era
- Department of Biochemistry and Molecular Biology, Egerton University, P.O. Box 536, Njoro, Kenya
| | - Modesta O Akoth
- Biotechnology Research Institute, Kenya Agricultural and Livestock Research Organization, P.O. Box 362, Kikuyu, Kenya; Department of Biochemistry and Molecular Biology, Egerton University, P.O. Box 536, Njoro, Kenya
| | - Vincent O Adung'a
- Department of Biochemistry and Molecular Biology, Egerton University, P.O. Box 536, Njoro, Kenya
| | - Bartholomew N Ondigo
- Department of Biochemistry and Molecular Biology, Egerton University, P.O. Box 536, Njoro, Kenya
| | - Paul O Mireji
- Biotechnology Research Institute, Kenya Agricultural and Livestock Research Organization, P.O. Box 362, Kikuyu, Kenya; Centre for Geographic Medicine Research - Coast, Kenya Medical Research Institute, PO Box 230-80108 Kilifi, Kenya.
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10
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Structure of trypanosome coat protein VSGsur and function in suramin resistance. Nat Microbiol 2021; 6:392-400. [PMID: 33462435 PMCID: PMC7116837 DOI: 10.1038/s41564-020-00844-1] [Citation(s) in RCA: 11] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/05/2020] [Accepted: 11/30/2020] [Indexed: 01/28/2023]
Abstract
Suramin has been a primary early-stage treatment for African trypanosomiasis for nearly 100 yr. Recent studies revealed that trypanosome strains that express the variant surface glycoprotein (VSG) VSGsur possess heightened resistance to suramin. Here, we show that VSGsur binds tightly to suramin but other VSGs do not. By solving high-resolution crystal structures of VSGsur and VSG13, we also demonstrate that these VSGs define a structurally divergent subgroup of the coat proteins. The co-crystal structure of VSGsur with suramin reveals that the chemically symmetric drug binds within a large cavity in the VSG homodimer asymmetrically, primarily through contacts of its central benzene rings. Structure-based, loss-of-contact mutations in VSGsur significantly decrease the affinity to suramin and lead to a loss of the resistance phenotype. Altogether, these data show that the resistance phenotype is dependent on the binding of suramin to VSGsur, establishing that the VSG proteins can possess functionality beyond their role in antigenic variation.
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11
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Lam NS, Long X, Su XZ, Lu F. Melaleuca alternifolia (tea tree) oil and its monoterpene constituents in treating protozoan and helminthic infections. Biomed Pharmacother 2020; 130:110624. [DOI: 10.1016/j.biopha.2020.110624] [Citation(s) in RCA: 18] [Impact Index Per Article: 4.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/23/2020] [Revised: 08/03/2020] [Accepted: 08/05/2020] [Indexed: 02/08/2023] Open
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Van den Kerkhof M, Sterckx YGJ, Leprohon P, Maes L, Caljon G. Experimental Strategies to Explore Drug Action and Resistance in Kinetoplastid Parasites. Microorganisms 2020; 8:E950. [PMID: 32599761 PMCID: PMC7356981 DOI: 10.3390/microorganisms8060950] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/31/2020] [Accepted: 06/22/2020] [Indexed: 12/17/2022] Open
Abstract
Kinetoplastids are the causative agents of leishmaniasis, human African trypanosomiasis, and American trypanosomiasis. They are responsible for high mortality and morbidity in (sub)tropical regions. Adequate treatment options are limited and have several drawbacks, such as toxicity, need for parenteral administration, and occurrence of treatment failure and drug resistance. Therefore, there is an urgency for the development of new drugs. Phenotypic screening already allowed the identification of promising new chemical entities with anti-kinetoplastid activity potential, but knowledge on their mode-of-action (MoA) is lacking due to the generally applied whole-cell based approach. However, identification of the drug target is essential to steer further drug discovery and development. Multiple complementary techniques have indeed been used for MoA elucidation. In this review, the different 'omics' approaches employed to define the MoA or mode-of-resistance of current reference drugs and some new anti-kinetoplastid compounds are discussed.
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Affiliation(s)
- Magali Van den Kerkhof
- Laboratory of Microbiology, Parasitology and Hygiene (LMPH), University of Antwerp, 2610 Wilrijk, Belgium; (M.V.d.K.); (L.M.)
| | - Yann G.-J. Sterckx
- Laboratory of Medical Biochemistry (LMB), University of Antwerp, 2610 Wilrijk, Belgium;
| | - Philippe Leprohon
- Centre de Recherche en Infectiologie du Centre de Recherche du Centre Hospitalier Universitaire de Québec, Université Laval, Québec, QC G1V 0A6, Canada;
| | - Louis Maes
- Laboratory of Microbiology, Parasitology and Hygiene (LMPH), University of Antwerp, 2610 Wilrijk, Belgium; (M.V.d.K.); (L.M.)
| | - Guy Caljon
- Laboratory of Microbiology, Parasitology and Hygiene (LMPH), University of Antwerp, 2610 Wilrijk, Belgium; (M.V.d.K.); (L.M.)
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Zoltner M, Campagnaro GD, Taleva G, Burrell A, Cerone M, Leung KF, Achcar F, Horn D, Vaughan S, Gadelha C, Zíková A, Barrett MP, de Koning HP, Field MC. Suramin exposure alters cellular metabolism and mitochondrial energy production in African trypanosomes. J Biol Chem 2020; 295:8331-8347. [PMID: 32354742 PMCID: PMC7294092 DOI: 10.1074/jbc.ra120.012355] [Citation(s) in RCA: 18] [Impact Index Per Article: 4.5] [Reference Citation Analysis] [Abstract] [Key Words] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/09/2020] [Revised: 04/21/2020] [Indexed: 12/27/2022] Open
Abstract
Introduced about a century ago, suramin remains a frontline drug for the management of early-stage East African trypanosomiasis (sleeping sickness). Cellular entry into the causative agent, the protozoan parasite Trypanosoma brucei, occurs through receptor-mediated endocytosis involving the parasite's invariant surface glycoprotein 75 (ISG75), followed by transport into the cytosol via a lysosomal transporter. The molecular basis of the trypanocidal activity of suramin remains unclear, but some evidence suggests broad, but specific, impacts on trypanosome metabolism (i.e. polypharmacology). Here we observed that suramin is rapidly accumulated in trypanosome cells proportionally to ISG75 abundance. Although we found little evidence that suramin disrupts glycolytic or glycosomal pathways, we noted increased mitochondrial ATP production, but a net decrease in cellular ATP levels. Metabolomics highlighted additional impacts on mitochondrial metabolism, including partial Krebs' cycle activation and significant accumulation of pyruvate, corroborated by increased expression of mitochondrial enzymes and transporters. Significantly, the vast majority of suramin-induced proteins were normally more abundant in the insect forms compared with the blood stage of the parasite, including several proteins associated with differentiation. We conclude that suramin has multiple and complex effects on trypanosomes, but unexpectedly partially activates mitochondrial ATP-generating activity. We propose that despite apparent compensatory mechanisms in drug-challenged cells, the suramin-induced collapse of cellular ATP ultimately leads to trypanosome cell death.
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Affiliation(s)
- Martin Zoltner
- School of Life Sciences, University of Dundee, Dundee, Scotland, United Kingdom
| | - Gustavo D Campagnaro
- Institute for Infection, Immunity, and Inflammation, College of Medical, Veterinary and Life Sciences, University of Glasgow, Glasgow, United Kingdom
| | - Gergana Taleva
- Institute of Parasitology, Biology Centre, Czech Academy of Sciences, Institute of Parasitology, Faculty of Science, University of South Bohemia, České Budějovice, Czech Republic
| | - Alana Burrell
- Department of Biological and Medical Sciences, Oxford Brookes University, Oxford, United Kingdom
| | - Michela Cerone
- Institute for Infection, Immunity, and Inflammation, College of Medical, Veterinary and Life Sciences, University of Glasgow, Glasgow, United Kingdom
| | - Ka-Fai Leung
- Department of Pathology, University of Cambridge, Cambridge, United Kingdom
| | - Fiona Achcar
- Wellcome Centre for Integrative Parasitology and Glasgow Polyomics, University of Glasgow, Glasgow, United Kingdom
| | - David Horn
- School of Life Sciences, University of Dundee, Dundee, Scotland, United Kingdom
| | - Sue Vaughan
- Department of Biological and Medical Sciences, Oxford Brookes University, Oxford, United Kingdom
| | - Catarina Gadelha
- School of Life Sciences, University of Nottingham, Nottingham, United Kingdom
| | - Alena Zíková
- Institute of Parasitology, Biology Centre, Czech Academy of Sciences, Institute of Parasitology, Faculty of Science, University of South Bohemia, České Budějovice, Czech Republic
| | - Michael P Barrett
- Wellcome Centre for Integrative Parasitology and Glasgow Polyomics, University of Glasgow, Glasgow, United Kingdom
| | - Harry P de Koning
- Institute for Infection, Immunity, and Inflammation, College of Medical, Veterinary and Life Sciences, University of Glasgow, Glasgow, United Kingdom
| | - Mark C Field
- School of Life Sciences, University of Dundee, Dundee, Scotland, United Kingdom .,Institute of Parasitology, Biology Centre, Czech Academy of Sciences, Institute of Parasitology, Faculty of Science, University of South Bohemia, České Budějovice, Czech Republic
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14
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Silva Pereira S, Heap J, Jones AR, Jackson AP. VAPPER: High-throughput variant antigen profiling in African trypanosomes of livestock. Gigascience 2020; 8:5556439. [PMID: 31494667 PMCID: PMC6735694 DOI: 10.1093/gigascience/giz091] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/03/2018] [Revised: 06/17/2019] [Accepted: 07/09/2019] [Indexed: 11/14/2022] Open
Abstract
BACKGROUND Analysing variant antigen gene families on a population scale is a difficult challenge for conventional methods of read mapping and variant calling due to the great variability in sequence, copy number, and genomic loci. In African trypanosomes, hemoparasites of humans and animals, this is complicated by variant antigen repertoires containing hundreds of genes subject to various degrees of sequence recombination. FINDINGS We introduce Variant Antigen Profiler (VAPPER), a tool that allows automated analysis of the variant surface glycoprotein repertoires of the most prevalent livestock African trypanosomes. VAPPER produces variant antigen profiles for any isolate of the veterinary pathogens Trypanosoma congolense and Trypanosoma vivax from genomic and transcriptomic sequencing data and delivers publication-ready figures that show how the queried isolate compares with a database of existing strains. VAPPER is implemented in Python. It can be installed to a local Galaxy instance from the ToolShed (https://toolshed.g2.bx.psu.edu/) or locally on a Linux platform via the command line (https://github.com/PGB-LIV/VAPPER). The documentation, requirements, examples, and test data are provided in the Github repository. CONCLUSION By establishing two different, yet comparable methodologies, our approach is the first to allow large-scale analysis of African trypanosome variant antigens, large multi-copy gene families that are otherwise refractory to high-throughput analysis.
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Affiliation(s)
- Sara Silva Pereira
- Department of Infection Biology, Institute of Infection and Global Health, University of Liverpool, Liverpool Science Park Ic2, 146 Brownlow Hill, Liverpool L3 5RF, UK
- Correspondence addres. Sara Silva Pereira, E-mail:
| | - John Heap
- Computational Biology Facility, University of Liverpool, Liverpool L69 7ZB, UK
| | - Andrew R Jones
- Institute of Integrative Biology, University of Liverpool, Liverpool L69 7ZB, UK
| | - Andrew P Jackson
- Department of Infection Biology, Institute of Infection and Global Health, University of Liverpool, Liverpool Science Park Ic2, 146 Brownlow Hill, Liverpool L3 5RF, UK
- Correspondence addres. Andrew P. Jackson, E-mail:
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15
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Capela R, Moreira R, Lopes F. An Overview of Drug Resistance in Protozoal Diseases. Int J Mol Sci 2019; 20:E5748. [PMID: 31731801 PMCID: PMC6888673 DOI: 10.3390/ijms20225748] [Citation(s) in RCA: 78] [Impact Index Per Article: 15.6] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/08/2019] [Revised: 11/11/2019] [Accepted: 11/13/2019] [Indexed: 01/14/2023] Open
Abstract
Protozoan diseases continue to be a worldwide social and economic health problem. Increased drug resistance, emerging cross resistance, and lack of new drugs with novel mechanisms of action significantly reduce the effectiveness of current antiprotozoal therapies. While drug resistance associated to anti-infective agents is a reality, society seems to remain unaware of its proportions and consequences. Parasites usually develops ingenious and innovative mechanisms to achieve drug resistance, which requires more research and investment to fight it. In this review, drug resistance developed by protozoan parasites Plasmodium, Leishmania, and Trypanosoma will be discussed.
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Affiliation(s)
- Rita Capela
- Instituto de Investigação do Medicamento (iMed.ULisboa), Faculdade de Farmácia, Universidade de Lisboa, Av. Prof. Gama Pinto, 1649-003 Lisboa, Portugal; (R.M.); (F.L.)
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16
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Wiedemar N, Zwyer M, Zoltner M, Cal M, Field MC, Mäser P. Expression of a specific variant surface glycoprotein has a major impact on suramin sensitivity and endocytosis in Trypanosoma brucei. FASEB Bioadv 2019; 1:595-608. [PMID: 32123811 PMCID: PMC6996322 DOI: 10.1096/fba.2019-00033] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/17/2019] [Revised: 04/17/2019] [Accepted: 07/25/2019] [Indexed: 11/11/2022] Open
Abstract
Suramin was introduced into the clinic a century ago and is still used to treat the first stage of acute human sleeping sickness. Due to its size and sixfold negative charge, uptake is mediated through endocytosis and the suramin receptor in trypanosomes is thought to be the invariant surface glycoprotein 75 (ISG75). Nevertheless, we recently identified a variant surface glycoprotein (VSGSur) that confers strong in vitro resistance to suramin in a Trypanosoma brucei rhodesiense line. In this study, we introduced VSGSur into the active bloodstream expression site of a T. b. brucei line. This caused suramin resistance and cross resistance to trypan blue. We quantified the endocytosis of different substrates by flow cytometry and showed that the expression of VSGSur strongly impairs the uptake of low-density lipoprotein (LDL) and transferrin, both imported by receptor-mediated endocytosis. However, bulk endocytosis and endocytosis of the trypanolytic factor were not affected, and the VSGSur -expressors did not exhibit a growth phenotype in the absence of suramin. Knockdown of ISG75 was synergistic with VSGSur expression, indicating that these two proteins are mediating distinct suramin resistance pathways. In conclusion, VSGSur causes suramin resistance in T. brucei bloodstream forms by decreasing specific, receptor-mediated endocytosis pathways.
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Affiliation(s)
- Natalie Wiedemar
- Swiss Tropical and Public Health InstituteBaselSwitzerland
- University of BaselBaselSwitzerland
| | - Michaela Zwyer
- Swiss Tropical and Public Health InstituteBaselSwitzerland
- University of BaselBaselSwitzerland
| | - Martin Zoltner
- School of Life SciencesUniversity of DundeeDundeeUnited Kingdom
| | - Monica Cal
- Swiss Tropical and Public Health InstituteBaselSwitzerland
- University of BaselBaselSwitzerland
| | - Mark C. Field
- School of Life SciencesUniversity of DundeeDundeeUnited Kingdom
| | - Pascal Mäser
- Swiss Tropical and Public Health InstituteBaselSwitzerland
- University of BaselBaselSwitzerland
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17
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Akazue PI, Ebiloma GU, Ajibola O, Isaac C, Onyekwelu K, Ezeh CO, Eze AA. Sustainable Elimination (Zero Cases) of Sleeping Sickness: How Far Are We from Achieving This Goal? Pathogens 2019; 8:E135. [PMID: 31470522 PMCID: PMC6789789 DOI: 10.3390/pathogens8030135] [Citation(s) in RCA: 10] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/09/2019] [Revised: 08/26/2019] [Accepted: 08/26/2019] [Indexed: 01/02/2023] Open
Abstract
The recent massive reduction in the numbers of fresh Human African Trypanosomiasis (HAT) infection has presented an opportunity for the global elimination of this disease. To prevent a possible resurgence, as was the case after the reduced transmission of the 1960s, surveillance needs to be sustained and the necessary tools for detection and treatment of cases need to be made available at the points of care. In this review, we examine the available resources and make recommendations for improvement to ensure the sustenance of the already achieved gains to keep the trend moving towards elimination.
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Affiliation(s)
- Pearl Ihuoma Akazue
- Department of Biochemistry, Faculty of Life Sciences, University of Benin, Benin City 300283, Nigeria
| | - Godwin U Ebiloma
- Institute of Infection, Immunity and Inflammation, College of Medical, Veterinary and Life Sciences, University of Glasgow, Glasgow G12 8TA, UK
| | - Olumide Ajibola
- Medical Research Council Unit The Gambia at London School of Hygiene and Tropical Medicine, Banjul PO Box 273, The Gambia
| | - Clement Isaac
- Department of Zoology, Faculty of Life Sciences, Ambrose Alli University, Ekpoma 310101, Nigeria
| | - Kenechukwu Onyekwelu
- Department of Medical Biochemistry, Faculty of Basic Medical Sciences, University of Nigeria, Enugu Campus, Enugu 410001, Nigeria
| | - Charles O Ezeh
- Department of Medical Biochemistry, Faculty of Basic Medical Sciences, University of Nigeria, Enugu Campus, Enugu 410001, Nigeria
| | - Anthonius Anayochukwu Eze
- Department of Medical Biochemistry, Faculty of Basic Medical Sciences, University of Nigeria, Enugu Campus, Enugu 410001, Nigeria.
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18
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Paulson CN, John K, Baxley RM, Kurniawan F, Orellana K, Francis R, Sobeck A, Eichman BF, Chazin WJ, Aihara H, Georg GI, Hawkinson JE, Bielinsky AK. The anti-parasitic agent suramin and several of its analogues are inhibitors of the DNA binding protein Mcm10. Open Biol 2019; 9:190117. [PMID: 31409229 PMCID: PMC6731595 DOI: 10.1098/rsob.190117] [Citation(s) in RCA: 11] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/06/2023] Open
Abstract
Minichromosome maintenance protein 10 (Mcm10) is essential for DNA unwinding by the replisome during S phase. It is emerging as a promising anti-cancer target as MCM10 expression correlates with tumour progression and poor clinical outcomes. Here we used a competition-based fluorescence polarization (FP) high-throughput screening (HTS) strategy to identify compounds that inhibit Mcm10 from binding to DNA. Of the five active compounds identified, only the anti-parasitic agent suramin exhibited a dose-dependent decrease in replication products in an in vitro replication assay. Structure–activity relationship evaluation identified several suramin analogues that inhibited ssDNA binding by the human Mcm10 internal domain and full-length Xenopus Mcm10, including analogues that are selective for Mcm10 over human RPA. Binding of suramin analogues to Mcm10 was confirmed by surface plasmon resonance (SPR). SPR and FP affinity determinations were highly correlated, with a similar rank between affinity and potency for killing colon cancer cells. Suramin analogue NF157 had the highest human Mcm10 binding affinity (FP Ki 170 nM, SPR KD 460 nM) and cell activity (IC50 38 µM). Suramin and its analogues are the first identified inhibitors of Mcm10 and probably block DNA binding by mimicking the DNA sugar phosphate backbone due to their extended, polysulfated anionic structures.
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Affiliation(s)
- Carolyn N Paulson
- Department of Medicinal Chemistry and Institute for Therapeutics Discovery & Development, College of Pharmacy, University of Minnesota, Minneapolis, MN 55414, USA
| | - Kristen John
- Department of Medicinal Chemistry and Institute for Therapeutics Discovery & Development, College of Pharmacy, University of Minnesota, Minneapolis, MN 55414, USA
| | - Ryan M Baxley
- Department of Biochemistry, Molecular Biology and Biophysics, College of Biological Sciences, University of Minnesota, Minneapolis, MN 55455, USA
| | - Fredy Kurniawan
- Department of Biochemistry, Molecular Biology and Biophysics, College of Biological Sciences, University of Minnesota, Minneapolis, MN 55455, USA
| | - Kayo Orellana
- Department of Biochemistry, Molecular Biology and Biophysics, College of Biological Sciences, University of Minnesota, Minneapolis, MN 55455, USA
| | - Rawle Francis
- Department of Medicinal Chemistry and Institute for Therapeutics Discovery & Development, College of Pharmacy, University of Minnesota, Minneapolis, MN 55414, USA
| | - Alexandra Sobeck
- Department of Biochemistry, Molecular Biology and Biophysics, College of Biological Sciences, University of Minnesota, Minneapolis, MN 55455, USA
| | - Brandt F Eichman
- Departments of Biological Sciences and Biochemistry, Center for Structural Biology, Vanderbilt University, Nashville, TN 37232, USA
| | - Walter J Chazin
- Departments of Biochemistry and Chemistry, Center for Structural Biology, Vanderbilt University, Nashville, TN 37240, USA
| | - Hideki Aihara
- Department of Biochemistry, Molecular Biology and Biophysics, College of Biological Sciences, University of Minnesota, Minneapolis, MN 55455, USA
| | - Gunda I Georg
- Department of Medicinal Chemistry and Institute for Therapeutics Discovery & Development, College of Pharmacy, University of Minnesota, Minneapolis, MN 55414, USA
| | - Jon E Hawkinson
- Department of Medicinal Chemistry and Institute for Therapeutics Discovery & Development, College of Pharmacy, University of Minnesota, Minneapolis, MN 55414, USA
| | - Anja-Katrin Bielinsky
- Department of Biochemistry, Molecular Biology and Biophysics, College of Biological Sciences, University of Minnesota, Minneapolis, MN 55455, USA
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19
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Thomas JA, Baker N, Hutchinson S, Dominicus C, Trenaman A, Glover L, Alsford S, Horn D. Insights into antitrypanosomal drug mode-of-action from cytology-based profiling. PLoS Negl Trop Dis 2018; 12:e0006980. [PMID: 30475806 PMCID: PMC6283605 DOI: 10.1371/journal.pntd.0006980] [Citation(s) in RCA: 29] [Impact Index Per Article: 4.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/25/2018] [Revised: 12/06/2018] [Accepted: 11/07/2018] [Indexed: 12/31/2022] Open
Abstract
Chemotherapy continues to have a major impact on reducing the burden of disease caused by trypanosomatids. Unfortunately though, the mode-of-action (MoA) of antitrypanosomal drugs typically remains unclear or only partially characterised. This is the case for four of five current drugs used to treat Human African Trypanosomiasis (HAT); eflornithine is a specific inhibitor of ornithine decarboxylase. Here, we used a panel of T. brucei cellular assays to probe the MoA of the current HAT drugs. The assays included DNA-staining followed by microscopy and quantitative image analysis, or flow cytometry; terminal dUTP nick end labelling to monitor mitochondrial (kinetoplast) DNA replication; antibody-based detection of sites of nuclear DNA damage; and fluorescent dye-staining of mitochondria or lysosomes. We found that melarsoprol inhibited mitosis; nifurtimox reduced mitochondrial protein abundance; pentamidine triggered progressive loss of kinetoplast DNA and disruption of mitochondrial membrane potential; and suramin inhibited cytokinesis. Thus, current antitrypanosomal drugs perturb distinct and specific cellular compartments, structures or cell cycle phases. Further exploiting the findings, we show that putative mitogen-activated protein-kinases contribute to the melarsoprol-induced mitotic defect, reminiscent of the mitotic arrest associated signalling cascade triggered by arsenicals in mammalian cells, used to treat leukaemia. Thus, cytology-based profiling can rapidly yield novel insight into antitrypanosomal drug MoA.
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Affiliation(s)
- James A. Thomas
- London School of Hygiene & Tropical Medicine, Keppel Street, London, United Kingdom
| | - Nicola Baker
- The Centre for Immunology and Infection, University of York, Heslington, York, United Kingdom
| | | | | | - Anna Trenaman
- Wellcome Trust Centre for Anti-Infectives Research, School of Life Sciences, University of Dundee, Dundee, United Kingdom
| | | | - Sam Alsford
- London School of Hygiene & Tropical Medicine, Keppel Street, London, United Kingdom
| | - David Horn
- Wellcome Trust Centre for Anti-Infectives Research, School of Life Sciences, University of Dundee, Dundee, United Kingdom
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20
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Silva Pereira S, Casas-Sánchez A, Haines LR, Ogugo M, Absolomon K, Sanders M, Kemp S, Acosta-Serrano Á, Noyes H, Berriman M, Jackson AP. Variant antigen repertoires in Trypanosoma congolense populations and experimental infections can be profiled from deep sequence data using universal protein motifs. Genome Res 2018; 28:1383-1394. [PMID: 30006414 PMCID: PMC6120623 DOI: 10.1101/gr.234146.118] [Citation(s) in RCA: 13] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/03/2018] [Accepted: 07/12/2018] [Indexed: 11/25/2022]
Abstract
African trypanosomes are vector-borne hemoparasites of humans and animals. In the mammal, parasites evade the immune response through antigenic variation. Periodic switching of the variant surface glycoprotein (VSG) coat covering their cell surface allows sequential expansion of serologically distinct parasite clones. Trypanosome genomes contain many hundreds of VSG genes, subject to rapid changes in nucleotide sequence, copy number, and chromosomal position. Thus, analyzing, or even quantifying, VSG diversity over space and time presents an enormous challenge to conventional techniques. Indeed, previous population genomic studies have overlooked this vital aspect of pathogen biology for lack of analytical tools. Here we present a method for analyzing population-scale VSG diversity in Trypanosoma congolense from deep sequencing data. Previously, we suggested that T. congolense VSGs segregate into defined “phylotypes” that do not recombine. In our data set comprising 41 T. congolense genome sequences from across Africa, these phylotypes are universal and exhaustive. Screening sequence contigs with diagnostic protein motifs accurately quantifies relative phylotype frequencies, providing a metric of VSG diversity, called the “variant antigen profile.” We applied our metric to VSG expression in the tsetse fly, showing that certain, rare VSG phylotypes may be preferentially expressed in infective, metacyclic-stage parasites. Hence, variant antigen profiling accurately and rapidly determines the T. congolense VSG gene and transcript repertoire from sequence data, without need for manual curation or highly contiguous sequences. It offers a tractable approach to measuring VSG diversity across strains and during infections, which is imperative to understanding the host–parasite interaction at population and individual scales.
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Affiliation(s)
- Sara Silva Pereira
- Department of Infection Biology, Institute of Infection and Global Health, University of Liverpool, Liverpool L3 5RF, United Kingdom
| | - Aitor Casas-Sánchez
- Department of Parasitology, Liverpool School of Tropical Medicine, Liverpool L3 5QA, United Kingdom
| | - Lee R Haines
- Department of Vector Biology, Liverpool School of Tropical Medicine, Liverpool L3 5QA, United Kingdom
| | - Moses Ogugo
- International Livestock Research Institute, Nairobi 00100, Kenya
| | - Kihara Absolomon
- International Livestock Research Institute, Nairobi 00100, Kenya
| | - Mandy Sanders
- Wellcome Trust Sanger Institute, Wellcome Genome Campus, Hinxton CB10 1SA, United Kingdom
| | - Steve Kemp
- International Livestock Research Institute, Nairobi 00100, Kenya
| | - Álvaro Acosta-Serrano
- Department of Parasitology, Liverpool School of Tropical Medicine, Liverpool L3 5QA, United Kingdom.,Department of Vector Biology, Liverpool School of Tropical Medicine, Liverpool L3 5QA, United Kingdom
| | - Harry Noyes
- Institute of Integrative Biology, University of Liverpool, Liverpool L69 7ZB, United Kingdom
| | - Matthew Berriman
- Wellcome Trust Sanger Institute, Wellcome Genome Campus, Hinxton CB10 1SA, United Kingdom
| | - Andrew P Jackson
- Department of Infection Biology, Institute of Infection and Global Health, University of Liverpool, Liverpool L3 5RF, United Kingdom
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21
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Franco J, Scarone L, Comini MA. Drugs and Drug Resistance in African and American Trypanosomiasis. ANNUAL REPORTS IN MEDICINAL CHEMISTRY 2018. [DOI: 10.1016/bs.armc.2018.08.003] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/18/2022]
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