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Wendo JK, Mbaria JM, Nyariki JN, Isaac AO. Ginkgo biloba attenuated detrimental inflammatory and oxidative events due to Trypanosoma brucei rhodesiense in mice treated with melarsoprol. PLoS Negl Trop Dis 2024; 18:e0012103. [PMID: 38620045 PMCID: PMC11045140 DOI: 10.1371/journal.pntd.0012103] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/06/2023] [Revised: 04/25/2024] [Accepted: 03/25/2024] [Indexed: 04/17/2024] Open
Abstract
BACKGROUND The severe late stage Human African Trypanosomiasis (HAT) caused by Trypanosoma brucei rhodesiense (T.b.r) is characterized by damage to the blood brain barrier, severe brain inflammation, oxidative stress and organ damage. Melarsoprol (MelB) is currently the only treatment available for this disease. MelB use is limited by its lethal neurotoxicity due to post-treatment reactive encephalopathy. This study sought to assess the potential of Ginkgo biloba (GB), a potent anti-inflammatory and antioxidant, to protect the integrity of the blood brain barrier and ameliorate detrimental inflammatory and oxidative events due to T.b.r in mice treated with MelB. METHODOLOGY Group one constituted the control; group two was infected with T.b.r; group three was infected with T.b.r and treated with 2.2 mg/kg melarsoprol for 10 days; group four was infected with T.b.r and administered with GB 80 mg/kg for 30 days; group five was given GB 80mg/kg for two weeks before infection with T.b.r, and continued thereafter and group six was infected with T.b.r, administered with GB and treated with MelB. RESULTS Co-administration of MelB and GB improved the survival rate of infected mice. When administered separately, MelB and GB protected the integrity of the blood brain barrier and improved neurological function in infected mice. Furthermore, the administration of MelB and GB prevented T.b.r-induced microcytic hypochromic anaemia and thrombocytopenia, as well as T.b.r-driven downregulation of total WBCs. Glutathione analysis showed that co-administration of MelB and GB prevented T.b.r-induced oxidative stress in the brain, spleen, heart and lungs. Notably, GB averted peroxidation and oxidant damage by ameliorating T.b.r and MelB-driven elevation of malondialdehyde (MDA) in the brain, kidney and liver. In fact, the co-administered group for the liver, registered the lowest MDA levels for infected mice. T.b.r-driven elevation of serum TNF-α, IFN-γ, uric acid and urea was abrogated by MelB and GB. Co-administration of MelB and GB was most effective in stabilizing TNFα levels. GB attenuated T.b.r and MelB-driven up-regulation of nitrite. CONCLUSION Utilization of GB as an adjuvant therapy may ameliorate detrimental effects caused by T.b.r infection and MelB toxicity during late stage HAT.
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Affiliation(s)
- Janet Khatenje Wendo
- The University of Nairobi, Department of Public Health, Pharmacology and Toxicology, Kangemi (Nairobi), Kenya
- The Technical University of Kenya, Department of Pharmaceutical Sciences and Technology, Nairobi, Kenya
| | - James Mucunu Mbaria
- The University of Nairobi, Department of Public Health, Pharmacology and Toxicology, Kangemi (Nairobi), Kenya
| | - James Nyabuga Nyariki
- The Technical University of Kenya, Department of Biochemistry and Biotechnology, Nairobi, Kenya
| | - Alfred Orina Isaac
- The Technical University of Kenya, Department of Pharmaceutical Sciences and Technology, Nairobi, Kenya
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Abdel-Baki PM, El-Sherei MM, Khaleel AE, Abdel-Sattar E, Salem MA, Okba MM. Correlation between secondary metabolites of Iris confusa Sealy and Iris pseudacorus L. and their newly explored antiprotozoal potentials. BMC Complement Med Ther 2023; 23:465. [PMID: 38104072 PMCID: PMC10725014 DOI: 10.1186/s12906-023-04294-0] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/19/2023] [Accepted: 12/05/2023] [Indexed: 12/19/2023] Open
Abstract
BACKGROUND In the last few decades, the use of plant extracts and their phytochemicals as candidates for the management of parasitic diseases has increased tremendously. Irises are aromatic and medicinal plants that have long been employed in the treatment of different infectious diseases by traditional healers in many cultures. This study aims to explore the potential of three common Iris species (I. confusa Sealy, I. pseudacorus L. and I. germanica L.) against infectious diseases. Their in vitro antiprotozoal potency against Plasmodium falciparum, Trypanosoma brucei brucei, T. b. rhodesiense, T. cruzi and Leishmania infantum beside their cytotoxicity on MRC-5 fibroblasts and primary peritoneal murine macrophages were examined. METHODS The secondary metabolites of the tested extracts were characterized by UPLC-HRMS/MS and Pearsons correlation was used to correlate them with the antiprotozoal activity. RESULTS Overall, the non-polar fractions (NPF) showed a significant antiprotozoal activity (score: sc 2 to 5) in contrast to the polar fractions (PF). I. confusa NPF was the most active extract against P. falciparum [IC50 of 1.08 μg/mL, selectivity index (S.I. 26.11) and sc 5] and L. infantum (IC50 of 12.7 μg/mL, S.I. 2.22 and sc 2). I. pseudacorus NPF was the most potent fraction against T. b. rhodesiense (IC50 of 8.17 μg/mL, S.I. 3.67 and sc 3). Monogalactosyldiacylglycerol glycolipid (18:3/18:3), triaceylglycerol (18:2/18:2/18:3), oleic acid, and triterpenoid irridals (spirioiridoconfal C and iso-iridobelamal A) were the top positively correlated metabolites with antiplasmodium and antileishmanial activities of I. confusa NPF. Tumulosic acid, ceramide sphingolipids, corosolic, maslinic, moreollic acids, pheophytin a, triaceylglycerols, mono- and digalactosyldiacylglycerols, phosphatidylglycerol (22:6/18:3), phosphatidylcholines (18:1/18:2), and triterpenoid irridal iso-iridobelamal A, were highly correlated to I. pseudacorus NPF anti- T. b. rhodesiense activity. The ADME study revealed proper drug likeness properties for certain highly corelated secondary metabolites. CONCLUSION This study is the sole map correlating I. confusa and I. pseudacorus secondary metabolites to their newly explored antiprotozoal activity.
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Affiliation(s)
- Passent M Abdel-Baki
- Department of Pharmacognosy, Faculty of Pharmacy, Cairo University, Kasr-El-Ainy Street, Cairo, 11562, Egypt.
| | - Moshera M El-Sherei
- Department of Pharmacognosy, Faculty of Pharmacy, Cairo University, Kasr-El-Ainy Street, Cairo, 11562, Egypt
| | - Amal E Khaleel
- Department of Pharmacognosy, Faculty of Pharmacy, Cairo University, Kasr-El-Ainy Street, Cairo, 11562, Egypt
| | - Essam Abdel-Sattar
- Department of Pharmacognosy, Faculty of Pharmacy, Cairo University, Kasr-El-Ainy Street, Cairo, 11562, Egypt
| | - Mohamed A Salem
- Department of Pharmacognosy, Faculty of Pharmacy, Menoufia University, Gamal Abd El Nasr St., Shibin Elkom, 32511, Menoufia, Egypt
| | - Mona M Okba
- Department of Pharmacognosy, Faculty of Pharmacy, Cairo University, Kasr-El-Ainy Street, Cairo, 11562, Egypt
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Pépin J. Sleeping sickness: time for dreaming. THE LANCET. INFECTIOUS DISEASES 2023; 23:387-388. [PMID: 36460028 DOI: 10.1016/s1473-3099(22)00686-7] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/06/2022] [Accepted: 10/06/2022] [Indexed: 12/03/2022]
Affiliation(s)
- Jacques Pépin
- Department of Microbiology and Infectious Diseases, Faculty of Medicine and Health Sciences, Université de Sherbrooke, Sherbrooke, QC J1H 5N4, Canada.
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Abstract
PURPOSE OF REVIEW Gambiense human African trypanosomiasis (gHAT), a disease that has killed hundreds of thousands as recently as the 1990s, could be on the verge of elimination or even eradication. This review describes recent developments that give us reasons for optimism as well as some caveats. RECENT FINDINGS New developments in diagnostic and vector control tools, and especially in treatment, make it possible to strive for elimination of transmission of gHAT by 2030, perhaps even eradication. SUMMARY Gambiense human African trypanosomiasis is a deadly infectious disease affecting West and Central Africa, South Sudan and Uganda, and transmitted between humans by tsetse flies. The disease has caused several major epidemics, the latest one in the 1990s. Thanks to recent innovations such as rapid diagnostic tests for population screening, a single-dose oral treatment and a highly efficient vector control strategy, interruption of transmission of the causative parasite is now within reach. If indeed gHAT has an exclusively human reservoir, this could even result in eradication of the disease. Even if there were an animal reservoir, on the basis of epidemiological data, it plays a limited role. Maintaining adequate postelimination surveillance in known historic foci, using the newly developed tools, should be sufficient to prevent any future resurgence.
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Lu Z, Wu D, Wang Z, Zhang H, Du Y, Wang G. Diminazene aceturate mitigates cardiomyopathy by interfering with renin-angiotensin system in a septic rat model. BMC Pharmacol Toxicol 2022; 23:44. [PMID: 35787308 PMCID: PMC9251020 DOI: 10.1186/s40360-022-00584-4] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/17/2021] [Accepted: 06/27/2022] [Indexed: 11/19/2022] Open
Abstract
Background There were limited studies investigating treatments of septic cardiomyopathy (SCM), which is a common complication during sepsis. A septic rat model created by cecal ligation and puncture (CLP) was used to investigate the effects of diminazene aceturate (DIZE) in SCM. Methods A total of 151 Wistar rats were randomly assigned into the sham, CLP, or CLP + DIZE group. Data evaluated postoperatively at 6, 12, 24, and 48 hours included: cardiac function; plasma concentrations of tumor necrosis factor-alpha (TNF-α), interleukin-6, angiotensin-(1–7) [Ang-(1–7)], angiotensin II (AngII), troponin I, and brain natriuretic peptide; expression levels of myocardial Ang-(1–7), angiotensin-converting enzyme (ACE), ACE2, and angiotensin type 1 and Mas receptors; and histological changes. Results We found that the CLP + DIZE group had a lower mortality compared to the CLP group (38.5% versus 61.5%) within 48 h postoperatively, although without statistical significance. In contrast to the sham group, the CLP group had decreased cardiac functions, increased myocardial injuries, and higher TNF-α levels, which were ameliorated in the CLP + DIZE group. Furthermore, administration of DIZE could reverse the decreases of myocardial Ang-(1–7) and ACE2 expressions in the CLP group, which finally minimized the myocardial microstructure disruptions. Conclusions It was concluded that DIZE could mitigate the development of SCM and preserve cardiac function during sepsis possibly by interfering with the renin-angiotensin system through promoting myocardial ACE2 expression and restoring local Ang-(1–7) levels. Supplementary Information The online version contains supplementary material available at 10.1186/s40360-022-00584-4.
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Affiliation(s)
- Zhaoqing Lu
- Department of Emergency Medicine, Beijing Friendship Hospital, Capital Medical University, Beijing, 100050, China
| | - Di Wu
- Department of Emergency Medicine, Beijing Friendship Hospital, Capital Medical University, Beijing, 100050, China
| | - Zheng Wang
- Department of Emergency Medicine, Beijing Friendship Hospital, Capital Medical University, Beijing, 100050, China
| | - Hanyu Zhang
- Department of Emergency Medicine, Beijing Friendship Hospital, Capital Medical University, Beijing, 100050, China
| | - Yufan Du
- Department of Emergency Medicine, Beijing Friendship Hospital, Capital Medical University, Beijing, 100050, China
| | - Guoxing Wang
- Department of Emergency Medicine, Beijing Friendship Hospital, Capital Medical University, Beijing, 100050, China.
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Ferreira TN, Brazil RP, McDowell MA, Cunha-Júnior EF, Costa PRR, Netto CD, Santos ECT, Genta FA. Effects of anti-Leishmania compounds in the behavior of the sand fly vector Lutzomyia longipalpis. PEST MANAGEMENT SCIENCE 2022; 78:2792-2805. [PMID: 35411662 DOI: 10.1002/ps.6900] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/14/2021] [Revised: 03/25/2022] [Accepted: 04/12/2022] [Indexed: 06/14/2023]
Abstract
BACKGROUND Leishmaniasis is an infectious parasitic disease caused by pathogens of the genus Leishmania transmitted through the bite of adult female sand flies. To reduce case numbers, it is necessary to combine different control approaches, especially those aimed at the sand fly vectors. Innovative forms of control with the use of attractive sugar baits explored the fact that adult sand flies need to feed on sugars of plant origin. Leishmania parasites develop in the gut of sand flies, interacting with the sugars in the diet of adults. Recent studies have shown that sugar baits containing plant-derived compounds can reduce sand fly survival, the number of parasites per gut, and the percentage of infected sand flies. Several synthetic compounds produced from naphthoquinones and pterocarpans have anti-parasitic activity on Leishmania amazonensis and/or Leishmania infantum in cell culture. This work aimed to assess the inclusion of these compounds in sugar baits for blocking transmission, targeting the development of the Leishmania parasite inside the sand fly vector. RESULTS We evaluated the attractant or repellent properties of these compounds, as well as of the reference compound N,N'-diethyl-m-toluamide (DEET), in sugar baits. We also observed changes in feeding preference caused by these compounds, looking for anti-feeding or stimulation of ingestion. Pterocarpanquinone L4 and pentamidine showed attractant and repellent properties, respectively. CONCLUSION Based on the effects in feeding preference and intake volume, pterocarpanquinone L6, and the pyrazole-derived compound P8 were chosen as the most promising compounds for the future development of anti-Leishmania sugar baits. © 2022 The Authors. Pest Management Science published by John Wiley & Sons Ltd on behalf of Society of Chemical Industry.
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Affiliation(s)
- Tainá Neves Ferreira
- Laboratório de Bioquímica e Fisiologia de Insetos, Instituto Oswaldo Cruz, Fiocruz, Rio de Janeiro, Brazil
| | - Reginaldo Peçanha Brazil
- Laboratório de Doenças Parasitárias, Instituto Oswaldo Cruz, Fiocruz, Rio de Janeiro, Brazil
- Instituto Nacional de Ciência e Tecnologia em Entomologia Molecular, Rio de Janeiro, Brazil
| | - Mary Ann McDowell
- Eck Institute for Global Health, Department of Biological Sciences, University of Notre Dame, Notre Dame, IN, USA
| | - Edézio Ferreira Cunha-Júnior
- Laboratório de Imunoparasitologia, Unidade Integrada de Pesquisa em Produtos Bioativos e Biociências, Universidade Federal do Rio de Janeiro, Campus UFRJ-Macaé, Macaé, Brazil
| | - Paulo Roberto Ribeiro Costa
- Laboratório de Química Bioorgânica, Instituto de Pesquisas de Produtos Naturais, Universidade Federal do Rio de Janeiro, Rio de Janeiro, Brazil
| | - Chaquip Daher Netto
- Laboratório de Química, Universidade Federal do Rio de Janeiro, Macaé, Brazil
| | - Eduardo Caio Torres Santos
- Laboratório de Bioquímica de Tripanossomatídeos, Instituto Oswaldo Cruz, Fiocruz, Rio de Janeiro, Brazil
| | - Fernando Ariel Genta
- Laboratório de Bioquímica e Fisiologia de Insetos, Instituto Oswaldo Cruz, Fiocruz, Rio de Janeiro, Brazil
- Instituto Nacional de Ciência e Tecnologia em Entomologia Molecular, Rio de Janeiro, Brazil
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Idro R, Ogwang R, Barragan A, Raimondo JV, Masocha W. Neuroimmunology of Common Parasitic Infections in Africa. Front Immunol 2022; 13:791488. [PMID: 35222377 PMCID: PMC8866860 DOI: 10.3389/fimmu.2022.791488] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/08/2021] [Accepted: 01/18/2022] [Indexed: 11/13/2022] Open
Abstract
Parasitic infections of the central nervous system are an important cause of morbidity and mortality in Africa. The neurological, cognitive, and psychiatric sequelae of these infections result from a complex interplay between the parasites and the host inflammatory response. Here we review some of the diseases caused by selected parasitic organisms known to infect the nervous system including Plasmodium falciparum, Toxoplasma gondii, Trypanosoma brucei spp., and Taenia solium species. For each parasite, we describe the geographical distribution, prevalence, life cycle, and typical clinical symptoms of infection and pathogenesis. We pay particular attention to how the parasites infect the brain and the interaction between each organism and the host immune system. We describe how an understanding of these processes may guide optimal diagnostic and therapeutic strategies to treat these disorders. Finally, we highlight current gaps in our understanding of disease pathophysiology and call for increased interrogation of these often-neglected disorders of the nervous system.
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Affiliation(s)
- Richard Idro
- College of Health Sciences, Makerere University, Kampala, Uganda.,Centre of Tropical Neuroscience, Kitgum, Uganda.,Nuffield Department of Medicine, Centre for Tropical Medicine and Global Health, University of Oxford, Oxford, United Kingdom
| | - Rodney Ogwang
- College of Health Sciences, Makerere University, Kampala, Uganda.,Centre of Tropical Neuroscience, Kitgum, Uganda.,Kenya Medical Research Institute (KEMRI) - Wellcome Trust Research Programme, Nairobi, Kenya
| | - Antonio Barragan
- Department of Molecular Biosciences, The Wenner-Gren Institute, Stockholm University, Stockholm, Sweden
| | - Joseph Valentino Raimondo
- Division of Cell Biology, Department of Human Biology, Neuroscience Institute and Institute of Infectious Disease and Molecular Medicine, Faculty of Health Sciences, University of Cape Town, Cape Town, South Africa
| | - Willias Masocha
- Department of Pharmacology and Therapeutics, Faculty of Pharmacy, Kuwait University, Safat, Kuwait
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Li M, Gaussmann S, Tippler B, Ott J, Popowicz GM, Schliebs W, Sattler M, Erdmann R, Kalel VC. Novel Trypanocidal Inhibitors that Block Glycosome Biogenesis by Targeting PEX3-PEX19 Interaction. Front Cell Dev Biol 2022; 9:737159. [PMID: 34988071 PMCID: PMC8721105 DOI: 10.3389/fcell.2021.737159] [Citation(s) in RCA: 2] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/06/2021] [Accepted: 11/15/2021] [Indexed: 12/02/2022] Open
Abstract
Human pathogenic trypanosomatid parasites harbor a unique form of peroxisomes termed glycosomes that are essential for parasite viability. We and others previously identified and characterized the essential Trypanosoma brucei ortholog TbPEX3, which is the membrane-docking factor for the cytosolic receptor PEX19 bound to the glycosomal membrane proteins. Knockdown of TbPEX3 expression leads to mislocalization of glycosomal membrane and matrix proteins, and subsequent cell death. As an early step in glycosome biogenesis, the PEX3–PEX19 interaction is an attractive drug target. We established a high-throughput assay for TbPEX3–TbPEX19 interaction and screened a compound library for small-molecule inhibitors. Hits from the screen were further validated using an in vitro ELISA assay. We identified three compounds, which exhibit significant trypanocidal activity but show no apparent toxicity to human cells. Furthermore, we show that these compounds lead to mislocalization of glycosomal proteins, which is toxic to the trypanosomes. Moreover, NMR-based experiments indicate that the inhibitors bind to PEX3. The inhibitors interfering with glycosomal biogenesis by targeting the TbPEX3–TbPEX19 interaction serve as starting points for further optimization and anti-trypanosomal drug development.
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Affiliation(s)
- Mengqiao Li
- Department of Systems Biochemistry, Faculty of Medicine, Institute of Biochemistry and Pathobiochemistry, Ruhr University Bochum, Bochum, Germany
| | - Stefan Gaussmann
- Institute of Structural Biology, Helmholtz Zentrum München, Neuherberg, Germany.,Department of Chemistry, Bavarian NMR Center, Technical University of Munich, Garching, Germany
| | - Bettina Tippler
- Department of Systems Biochemistry, Faculty of Medicine, Institute of Biochemistry and Pathobiochemistry, Ruhr University Bochum, Bochum, Germany
| | - Julia Ott
- Department of Systems Biochemistry, Faculty of Medicine, Institute of Biochemistry and Pathobiochemistry, Ruhr University Bochum, Bochum, Germany
| | - Grzegorz M Popowicz
- Institute of Structural Biology, Helmholtz Zentrum München, Neuherberg, Germany.,Department of Chemistry, Bavarian NMR Center, Technical University of Munich, Garching, Germany
| | - Wolfgang Schliebs
- Department of Systems Biochemistry, Faculty of Medicine, Institute of Biochemistry and Pathobiochemistry, Ruhr University Bochum, Bochum, Germany
| | - Michael Sattler
- Institute of Structural Biology, Helmholtz Zentrum München, Neuherberg, Germany.,Department of Chemistry, Bavarian NMR Center, Technical University of Munich, Garching, Germany
| | - Ralf Erdmann
- Department of Systems Biochemistry, Faculty of Medicine, Institute of Biochemistry and Pathobiochemistry, Ruhr University Bochum, Bochum, Germany
| | - Vishal C Kalel
- Department of Systems Biochemistry, Faculty of Medicine, Institute of Biochemistry and Pathobiochemistry, Ruhr University Bochum, Bochum, Germany
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Zuma AA, Teixeira de Macedo-Silva S, Achari A, Vinayagam J, Bhattacharjee P, Chatterjee S, Gupta VK, Cristina de Sousa Leite A, Souza de Castro L, Jaisankar P, de Souza W. Furan derivatives impair proliferation and affect ultrastructural organization of Trypanosoma cruzi and Leishmania amazonensis. Exp Parasitol 2021; 224:108100. [PMID: 33744229 DOI: 10.1016/j.exppara.2021.108100] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/21/2020] [Revised: 02/26/2021] [Accepted: 03/08/2021] [Indexed: 11/17/2022]
Abstract
Chagas disease and leishmaniasis are neglected diseases caused by parasites of the Trypanosomatidae family and together they affect millions of people in the five continents. The treatment of Chagas disease is based on benznidazole, whereas for leishmaniasis few drugs are available, such as amphotericin B and miltefosine. In both cases, the current treatment is not entirely efficient due to toxicity or side effects. Encouraged by the need to discover valid targets and new treatment options, we evaluated 8 furan compounds against Trypanosoma cruzi and Leishmania amazonensis, considering their effects against proliferation, infection, and ultrastructure. Many of them were able to impair T. cruzi and L. amazonensis proliferation, as well as cause ultrastructural alterations, such as Golgi apparatus disorganization, autophagosome formation, and mitochondrial swelling. Taken together, the results obtained so far make these compounds eligible for further steps of chemotherapy study.
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Affiliation(s)
- Aline Araujo Zuma
- Laboratório de Ultraestrutura Celular Hertha Meyer, Instituto de Biofísica Carlos Chagas Filho Universidade Federal do Rio de Janeiro, Av. Carlos Chagas Filho, 373, Cidade Universitária, Rio de Janeiro, CEP 21941-902, Brazil; Instituto Nacional de Ciência e Tecnologia de Biologia Estrutural e Bioimagem, Av. Carlos Chagas Filho, 373, Cidade Universitária, Rio de Janeiro, CEP 21941-902, Brazil
| | - Sara Teixeira de Macedo-Silva
- Laboratório de Ultraestrutura Celular Hertha Meyer, Instituto de Biofísica Carlos Chagas Filho Universidade Federal do Rio de Janeiro, Av. Carlos Chagas Filho, 373, Cidade Universitária, Rio de Janeiro, CEP 21941-902, Brazil; Instituto Nacional de Ciência e Tecnologia de Biologia Estrutural e Bioimagem, Av. Carlos Chagas Filho, 373, Cidade Universitária, Rio de Janeiro, CEP 21941-902, Brazil
| | - Anushree Achari
- Organic & Medicinal Chemistry Division, CSIR-Indian Institute of Chemical Biology, 4, Raja S. C. Mullick Road, Kolkata, 700 032, India
| | - Jayaraman Vinayagam
- Organic & Medicinal Chemistry Division, CSIR-Indian Institute of Chemical Biology, 4, Raja S. C. Mullick Road, Kolkata, 700 032, India
| | - Pinaki Bhattacharjee
- Organic & Medicinal Chemistry Division, CSIR-Indian Institute of Chemical Biology, 4, Raja S. C. Mullick Road, Kolkata, 700 032, India
| | - Sourav Chatterjee
- Organic & Medicinal Chemistry Division, CSIR-Indian Institute of Chemical Biology, 4, Raja S. C. Mullick Road, Kolkata, 700 032, India
| | - Vivek Kumar Gupta
- Organic & Medicinal Chemistry Division, CSIR-Indian Institute of Chemical Biology, 4, Raja S. C. Mullick Road, Kolkata, 700 032, India
| | - Amanda Cristina de Sousa Leite
- Laboratório de Ultraestrutura Celular Hertha Meyer, Instituto de Biofísica Carlos Chagas Filho Universidade Federal do Rio de Janeiro, Av. Carlos Chagas Filho, 373, Cidade Universitária, Rio de Janeiro, CEP 21941-902, Brazil; Instituto Nacional de Ciência e Tecnologia de Biologia Estrutural e Bioimagem, Av. Carlos Chagas Filho, 373, Cidade Universitária, Rio de Janeiro, CEP 21941-902, Brazil
| | - Lucas Souza de Castro
- Laboratório de Ultraestrutura Celular Hertha Meyer, Instituto de Biofísica Carlos Chagas Filho Universidade Federal do Rio de Janeiro, Av. Carlos Chagas Filho, 373, Cidade Universitária, Rio de Janeiro, CEP 21941-902, Brazil; Instituto Nacional de Ciência e Tecnologia de Biologia Estrutural e Bioimagem, Av. Carlos Chagas Filho, 373, Cidade Universitária, Rio de Janeiro, CEP 21941-902, Brazil
| | - Parasuraman Jaisankar
- Organic & Medicinal Chemistry Division, CSIR-Indian Institute of Chemical Biology, 4, Raja S. C. Mullick Road, Kolkata, 700 032, India.
| | - Wanderley de Souza
- Laboratório de Ultraestrutura Celular Hertha Meyer, Instituto de Biofísica Carlos Chagas Filho Universidade Federal do Rio de Janeiro, Av. Carlos Chagas Filho, 373, Cidade Universitária, Rio de Janeiro, CEP 21941-902, Brazil; Instituto Nacional de Ciência e Tecnologia de Biologia Estrutural e Bioimagem, Av. Carlos Chagas Filho, 373, Cidade Universitária, Rio de Janeiro, CEP 21941-902, Brazil.
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A phase 1 trial of 4-(N-(S-penicillaminylacetyl)amino)-phenylarsonous acid (PENAO) in patients with advanced solid tumours. Cancer Chemother Pharmacol 2021; 87:613-620. [PMID: 33496801 DOI: 10.1007/s00280-020-04225-7] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/11/2020] [Accepted: 12/28/2020] [Indexed: 10/22/2022]
Abstract
PURPOSE This phase I study was conducted to evaluate the safety and Maximum Tolerated Dose of PENAO (4-(N-(S-penicillaminylacetyl)amino)-phenylarsonous acid), a second-generation organic arsenical with anti-mitochondrial activity, when given as a continuous intravenous infusion (CIVI), in patients with advanced solid tumours. METHODS Eligibility criteria for this trial included age ≥ 18 years, advanced solid tumour, ECOG Performance Status ≤ 1 and adequate organ function. PENAO was administered by CIVI, with dose levels initially increased by infusion duration in a 21-day cycle at a fixed daily dose and then increased daily dose. Standard dose-limiting toxicity (DLT) definitions were used in a "3 + 3" design. Patients had regular monitoring of toxicity and efficacy. Pharmacokinetic assays of serum and urine As were performed. RESULTS Twenty-six patients were treated across 8 dose levels. The only dose-limiting toxicity (DLT) observed was fatigue, that occurred in one patient treated at the highest dose level of 9 mg/m2/day. No significant organ toxicity or objective responses were observed, although there were two patients with stable disease lasting up to 7 months. Pharmacokinetic analysis unexpectedly indicated a half-life of 9-19 days, invalidating the CIVI dosing resulting in discontinuation of the study before the RP2D was defined. CONCLUSIONS PENAO was administered by CIVI at dose levels up to 9 mg/m2/day with only one DLT noted. Pharmacokinetic studies invalidated the rationale for continuous dosing and led to discontinuation of the trial without defining a RP2D. Future clinical development of PENAO will use intermittent dosing schedule, alone and in combination with rapamycin.
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Johé P, Jaenicke E, Neuweiler H, Schirmeister T, Kersten C, Hellmich UA. Structure, interdomain dynamics, and pH-dependent autoactivation of pro-rhodesain, the main lysosomal cysteine protease from African trypanosomes. J Biol Chem 2021; 296:100565. [PMID: 33745969 PMCID: PMC8080524 DOI: 10.1016/j.jbc.2021.100565] [Citation(s) in RCA: 7] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/19/2020] [Revised: 02/18/2021] [Accepted: 03/17/2021] [Indexed: 02/06/2023] Open
Abstract
Rhodesain is the lysosomal cathepsin L-like cysteine protease of Trypanosoma brucei rhodesiense, the causative agent of Human African Trypanosomiasis. The enzyme is essential for the proliferation and pathogenicity of the parasite as well as its ability to overcome the blood-brain barrier of the host. Lysosomal cathepsins are expressed as zymogens with an inactivating prodomain that is cleaved under acidic conditions. A structure of the uncleaved maturation intermediate from a trypanosomal cathepsin L-like protease is currently not available. We thus established the heterologous expression of T. brucei rhodesiense pro-rhodesain in Escherichia coli and determined its crystal structure. The trypanosomal prodomain differs from nonparasitic pro-cathepsins by a unique, extended α-helix that blocks the active site and whose side-chain interactions resemble those of the antiprotozoal inhibitor K11777. Interdomain dynamics between pro- and core protease domain as observed by photoinduced electron transfer fluorescence correlation spectroscopy increase at low pH, where pro-rhodesain also undergoes autocleavage. Using the crystal structure, molecular dynamics simulations, and mutagenesis, we identify a conserved interdomain salt bridge that prevents premature intramolecular cleavage at higher pH values and may thus present a control switch for the observed pH sensitivity of proenzyme cleavage in (trypanosomal) CathL-like proteases.
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Affiliation(s)
- Patrick Johé
- Institute of Pharmaceutical and Biomedical Sciences, Johannes Gutenberg-University, Mainz, Germany
| | - Elmar Jaenicke
- Institute for Molecular Physiology, Johannes Gutenberg-University, Mainz, Germany
| | - Hannes Neuweiler
- Department for Biotechnology and Biophysics, Julius-Maximilians-University, Würzburg, Germany
| | - Tanja Schirmeister
- Institute of Pharmaceutical and Biomedical Sciences, Johannes Gutenberg-University, Mainz, Germany
| | - Christian Kersten
- Institute of Pharmaceutical and Biomedical Sciences, Johannes Gutenberg-University, Mainz, Germany.
| | - Ute A Hellmich
- Department of Chemistry, Biochemistry Division, Johannes Gutenberg-University, Mainz, Germany; Centre for Biomolecular Magnetic Resonance (BMRZ), Goethe University, Frankfurt, Germany.
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Muraca G, Berti IR, Sbaraglini ML, Fávaro WJ, Durán N, Castro GR, Talevi A. Trypanosomatid-Caused Conditions: State of the Art of Therapeutics and Potential Applications of Lipid-Based Nanocarriers. Front Chem 2020; 8:601151. [PMID: 33324615 PMCID: PMC7726426 DOI: 10.3389/fchem.2020.601151] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/31/2020] [Accepted: 10/19/2020] [Indexed: 11/13/2022] Open
Abstract
Trypanosomatid-caused conditions (African trypanosomiasis, Chagas disease, and leishmaniasis) are neglected tropical infectious diseases that mainly affect socioeconomically vulnerable populations. The available therapeutics display substantial limitations, among them limited efficacy, safety issues, drug resistance, and, in some cases, inconvenient routes of administration, which made the scenarios with insufficient health infrastructure settings inconvenient. Pharmaceutical nanocarriers may provide solutions to some of these obstacles, improving the efficacy-safety balance and tolerability to therapeutic interventions. Here, we overview the state of the art of therapeutics for trypanosomatid-caused diseases (including approved drugs and drugs undergoing clinical trials) and the literature on nanolipid pharmaceutical carriers encapsulating approved and non-approved drugs for these diseases. Numerous studies have focused on the obtention and preclinical assessment of lipid nanocarriers, particularly those addressing the two currently most challenging trypanosomatid-caused diseases, Chagas disease, and leishmaniasis. In general, in vitro and in vivo studies suggest that delivering the drugs using such type of nanocarriers could improve the efficacy-safety balance, diminishing cytotoxicity and organ toxicity, especially in leishmaniasis. This constitutes a very relevant outcome, as it opens the possibility to extended treatment regimens and improved compliance. Despite these advances, last-generation nanosystems, such as targeted nanocarriers and hybrid systems, have still not been extensively explored in the field of trypanosomatid-caused conditions and represent promising opportunities for future developments. The potential use of nanotechnology in extended, well-tolerated drug regimens is particularly interesting in the light of recent descriptions of quiescent/dormant stages of Leishmania and Trypanosoma cruzi, which have been linked to therapeutic failure.
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Affiliation(s)
- Giuliana Muraca
- Laboratory of Bioactive Research and Development (LIDeB), Department of Biological Sciences, Faculty of Exact Sciences, University of La Plata (UNLP), La Plata, Argentina
- Administración Nacional de Medicamentos, Alimentos y Tecnología Médica (ANMAT), Buenos Aires, Argentina
| | - Ignacio Rivero Berti
- Laboratorio de Nanobiomateriales, Centro de Investigación y Desarrollo en Fermentaciones Industriales (CINDEFI), Departamento de Química, Facultad de Ciencias Exactas, Universidad Nacional de La Plata (UNLP) -CONICET (CCT La Plata), La Plata, Argentina
| | - María L. Sbaraglini
- Laboratory of Bioactive Research and Development (LIDeB), Department of Biological Sciences, Faculty of Exact Sciences, University of La Plata (UNLP), La Plata, Argentina
| | - Wagner J. Fávaro
- Laboratory of Urogenital Carcinogenesis and Immunotherapy, Department of Structural and Functional Biology, Institute of Biology, University of Campinas (UNICAMP), Campinas, Brazil
| | - Nelson Durán
- Laboratory of Urogenital Carcinogenesis and Immunotherapy, Department of Structural and Functional Biology, Institute of Biology, University of Campinas (UNICAMP), Campinas, Brazil
- Nanomedicine Research Unit (Nanomed), Federal University of ABC (UFABC), Santo André, Brazil
| | - Guillermo R. Castro
- Laboratorio de Nanobiomateriales, Centro de Investigación y Desarrollo en Fermentaciones Industriales (CINDEFI), Departamento de Química, Facultad de Ciencias Exactas, Universidad Nacional de La Plata (UNLP) -CONICET (CCT La Plata), La Plata, Argentina
| | - Alan Talevi
- Laboratory of Bioactive Research and Development (LIDeB), Department of Biological Sciences, Faculty of Exact Sciences, University of La Plata (UNLP), La Plata, Argentina
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Therapeutic Effect of Diminazene Aceturate on Parasitic Blood Fluke Schistosoma mansoni Infection. Antimicrob Agents Chemother 2020; 64:AAC.01372-20. [PMID: 32816737 DOI: 10.1128/aac.01372-20] [Citation(s) in RCA: 15] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/29/2020] [Accepted: 08/13/2020] [Indexed: 01/30/2023] Open
Abstract
Praziquantel is currently the only drug available to treat schistosomiasis, a disease of enormous public health significance caused by a blood fluke of the genus Schistosoma Diminazene, a drug approved by the FDA, has been successfully used to treat diseases caused by blood protozoan parasites. In this study, we evaluated the antiparasitic properties of diminazene against Schistosoma mansoni ex vivo and in mice harboring either chronic or early S. mansoni infections. In vitro, we monitored phenotypic and tegumental changes as well as the effects of the drug on pairing and egg production. In mice infected with either adult (chronic infection) or immature (early infection) worms, diminazene was administered intraperitoneally (10 to 100 mg/kg of body weight) or by oral gavage (100 to 400 mg/kg), and we studied the influence of the drug on worm burden and egg production. Liver and spleen pathologies and serum aminotransferase levels were also analyzed. In vitro, 50% effective concentrations (EC50) and EC90 revealed that diminazene is able to kill both immature and adult parasites, and its effect was time and concentration dependent. In addition, confocal laser scanning microscopy showed morphological alterations in the teguments of schistosomes. In an animal model, the influence of the drug on worm burden, egg production, hepatomegaly, and splenomegaly depended on the dosing regimen applied and the route of administration. Diminazene also caused a significant reduction in aminotransferase levels. Comparatively, diminazene treatment was more effective in chronic infection than in early infection. In tandem, our study revealed that diminazene possesses anthelmintic properties and inhibits liver injury caused by Schistosoma eggs.
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Impact of diminazene aceturate on renin-angiotensin system, infectious myocarditis and skeletal myositis in mice: An in vitro and in vivo study. Life Sci 2020; 257:118067. [PMID: 32652140 DOI: 10.1016/j.lfs.2020.118067] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/24/2020] [Revised: 06/26/2020] [Accepted: 07/05/2020] [Indexed: 12/27/2022]
Abstract
Although renin-angiotensin system (RAS) imbalance is manifested in cardiomyopathies with different etiologies, the impact of RAS effectors on Chagas cardiomyopathy and skeletal myositis is poorly understood. Given that diminazene aceturate (DMZ) shares trypanocidal, angiotensin-converting enzyme 2 (ACE2) and angiotensin-(1-7) stimulatory effects, we investigated the impact of DMZ on cardiomyocytes infection in vitro, renin-angiotensin system, Chagas cardiomyopathy and skeletal myositis in vivo. Cardiomyocytes and T. cruzi were used to evaluate DMZ toxicity in vitro. The impact of 20-days DMZ treatment (1 mg/kg) was also investigated in uninfected and T. cruzi-infected mice as follows: control uninfected and untreated, uninfected treated with DMZ, infected untreated and infected treated with DMZ. DMZ had low toxicity on cardiomyocytes, induced dose-dependent antiparasitic activity on T. cruzi trypomastigotes, and reduced parasite load but not infection rates in cardiomyocytes. DMZ increased ACE2 activity and angiotensin-(1-7) plasma levels but exerted no interference on angiotensin-converting enzyme (ACE) activity, ACE, ACE2 and angiotensin II levels in uninfected and infected mice. DMZ treatment also reduced IFN-γ and IL-2 circulating levels but was ineffective in attenuating parasitemia, MCP-1, IL-10, anti-T. cruzi IgG, nitrite/nitrate and malondialdehyde production, myocarditis and skeletal myositis compared to infected untreated animals. As the antiparasitic effect of DMZ in vitro did not manifest in vivo, this drug exhibited limited relevance to the treatment of Chagas disease. Although DMZ is effective in upregulating angiotensin-(1-7) levels, this molecule does not act as a potent modulator of T. cruzi infection, which can establish heart and skeletal muscle parasitism, lipid oxidation and inflammatory damage, even in the presence of high concentrations of this RAS effector.
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Canever MF, Miletti LC. Screening and Identification of Pathogen Box® Compounds with anti-Trypanosoma evansi Activity. Acta Trop 2020; 206:105421. [PMID: 32112721 DOI: 10.1016/j.actatropica.2020.105421] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/01/2019] [Revised: 02/06/2020] [Accepted: 02/24/2020] [Indexed: 11/18/2022]
Abstract
The development of new drugs targeting neglected animal diseases is imperative. In Asia and South America, Trypanosoma evansi is a pathogen that affects horses and other species, causing economic losses associated with reduced animal productivity and death. In order to accelerate the identification of drugs with activity against neglected diseases, Medicines for Malaria Venture has developed Pathogen Box®, a library of 400 different molecules. The present work aimed to identify compounds present in the Pathogen Box® library, measuring in vitro activity against T. evansi. Among the 400 compounds, 5 showed anti-T.evansi activity: pentamidine, MMV688410, MMV687273, MMV022478 and auranofin. Suramin, a trypanocidal activity molecule present on the Pathogen Box® reference compound list, demonstrated no anti-T. evansi activity in the in vitro assays. MMV688410 is the most promising candidate because it induces death and reduces the number of parasites in cell culture, and mainly because its mechanism of action is probably associated with inhibition of trypanosomal reductase enzyme, an exclusive target of trypanosomatides. Further in vitro and in vivo assays are needed to determine the efficacy of the compounds identified in this work, especially by associating tissue distribution and the ability of drugs to cross the blood brain barrier, as T. evansi is able to invade the central nervous system.
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Affiliation(s)
- Mariana Feltrin Canever
- Departamento de Produção Animal e Alimentos, Centro de Ciências Agroveterinárias (CAV), Universidade do Estado de Santa Catarina (UDESC), Av. Luís de Camões, 2090, Lages, SC 88520-000 Brazil
| | - Luiz Claudio Miletti
- Departamento de Produção Animal e Alimentos, Centro de Ciências Agroveterinárias (CAV), Universidade do Estado de Santa Catarina (UDESC), Av. Luís de Camões, 2090, Lages, SC 88520-000 Brazil.
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16
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Ehrenkaufer G, Li P, Stebbins EE, Kangussu-Marcolino MM, Debnath A, White CV, Moser MS, DeRisi J, Gisselberg J, Yeh E, Wang SC, Company AH, Monti L, Caffrey CR, Huston CD, Wang B, Singh U. Identification of anisomycin, prodigiosin and obatoclax as compounds with broad-spectrum anti-parasitic activity. PLoS Negl Trop Dis 2020; 14:e0008150. [PMID: 32196500 PMCID: PMC7112225 DOI: 10.1371/journal.pntd.0008150] [Citation(s) in RCA: 12] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/25/2019] [Revised: 04/01/2020] [Accepted: 02/18/2020] [Indexed: 01/20/2023] Open
Abstract
Parasitic infections are a major source of human suffering, mortality, and economic loss, but drug development for these diseases has been stymied by the significant expense involved in bringing a drug though clinical trials and to market. Identification of single compounds active against multiple parasitic pathogens could improve the economic incentives for drug development as well as simplifying treatment regimens. We recently performed a screen of repurposed compounds against the protozoan parasite Entamoeba histolytica, causative agent of amebic dysentery, and identified four compounds (anisomycin, prodigiosin, obatoclax and nithiamide) with low micromolar potency and drug-like properties. Here, we extend our investigation of these drugs. We assayed the speed of killing of E. histolytica trophozoites and found that all four have more rapid action than the current drug of choice, metronidazole. We further established a multi-institute collaboration to determine whether these compounds may have efficacy against other parasites and opportunistic pathogens. We found that anisomycin, prodigiosin and obatoclax all have broad-spectrum antiparasitic activity in vitro, including activity against schistosomes, T. brucei, and apicomplexan parasites. In several cases, the drugs were found to have significant improvements over existing drugs. For instance, both obatoclax and prodigiosin were more efficacious at inhibiting the juvenile form of Schistosoma than the current standard of care, praziquantel. Additionally, low micromolar potencies were observed against pathogenic free-living amebae (Naegleria fowleri, Balamuthia mandrillaris and Acanthamoeba castellanii), which cause CNS infection and for which there are currently no reliable treatments. These results, combined with the previous human use of three of these drugs (obatoclax, anisomycin and nithiamide), support the idea that these compounds could serve as the basis for the development of broad-spectrum anti-parasitic drugs.
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Affiliation(s)
- Gretchen Ehrenkaufer
- Division of Infectious Diseases, Department of Internal Medicine, Stanford University, Stanford, CA, United States of America
| | - Pengyang Li
- Department of Bioengineering, Stanford University, Stanford, CA, United States of America
| | - Erin E. Stebbins
- Department of Medicine, University of Vermont Larner College of Medicine, Burlington, Vermont, United States of America
| | - Monica M. Kangussu-Marcolino
- Division of Infectious Diseases, Department of Internal Medicine, Stanford University, Stanford, CA, United States of America
| | - Anjan Debnath
- Center for Discovery and Innovation in Parasitic Diseases, Skaggs School of Pharmacy and Pharmaceutical Sciences, University of California, San Diego, La Jolla, CA, United States of America
| | - Corin V. White
- Department of Biochemistry and Biophysics, University of California, San Francisco, San Francisco, California, United States of America
| | - Matthew S. Moser
- Department of Biochemistry and Biophysics, University of California, San Francisco, San Francisco, California, United States of America
| | - Joseph DeRisi
- Department of Biochemistry and Biophysics, University of California, San Francisco, San Francisco, California, United States of America
| | - Jolyn Gisselberg
- Department of Biochemistry, Stanford Medical School, Stanford University, Stanford, CA, United States of America
| | - Ellen Yeh
- Department of Biochemistry, Stanford Medical School, Stanford University, Stanford, CA, United States of America
- Department of Microbiology and Immunology, Stanford University, Stanford, CA, United States of America
- Department of Pathology, Stanford University, Stanford, CA, United States of America
| | - Steven C. Wang
- Center for Discovery and Innovation in Parasitic Diseases, Skaggs School of Pharmacy and Pharmaceutical Sciences, University of California, San Diego, La Jolla, CA, United States of America
| | - Ana Hervella Company
- Center for Discovery and Innovation in Parasitic Diseases, Skaggs School of Pharmacy and Pharmaceutical Sciences, University of California, San Diego, La Jolla, CA, United States of America
| | - Ludovica Monti
- Center for Discovery and Innovation in Parasitic Diseases, Skaggs School of Pharmacy and Pharmaceutical Sciences, University of California, San Diego, La Jolla, CA, United States of America
| | - Conor R. Caffrey
- Center for Discovery and Innovation in Parasitic Diseases, Skaggs School of Pharmacy and Pharmaceutical Sciences, University of California, San Diego, La Jolla, CA, United States of America
| | - Christopher D. Huston
- Department of Medicine, University of Vermont Larner College of Medicine, Burlington, Vermont, United States of America
| | - Bo Wang
- Department of Bioengineering, Stanford University, Stanford, CA, United States of America
- Department of Developmental Biology, Stanford University School of Medicine, Stanford, CA, United States of America
| | - Upinder Singh
- Division of Infectious Diseases, Department of Internal Medicine, Stanford University, Stanford, CA, United States of America
- Department of Microbiology and Immunology, Stanford University, Stanford, CA, United States of America
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P De Koning H. The Drugs of Sleeping Sickness: Their Mechanisms of Action and Resistance, and a Brief History. Trop Med Infect Dis 2020; 5:E14. [PMID: 31963784 PMCID: PMC7157662 DOI: 10.3390/tropicalmed5010014] [Citation(s) in RCA: 43] [Impact Index Per Article: 10.8] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/19/2019] [Revised: 01/15/2020] [Accepted: 01/16/2020] [Indexed: 12/17/2022] Open
Abstract
With the incidence of sleeping sickness in decline and genuine progress being made towards the WHO goal of eliminating sleeping sickness as a major public health concern, this is a good moment to evaluate the drugs that 'got the job done': their development, their limitations and the resistance that the parasites developed against them. This retrospective looks back on the remarkable story of chemotherapy against trypanosomiasis, a story that goes back to the very origins and conception of chemotherapy in the first years of the 20 century and is still not finished today.
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Affiliation(s)
- Harry P De Koning
- Institute of Infection, Immunity and Inflammation, University of Glasgow, Glasgow G12 8TA, UK
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18
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Neopterin and CXCL-13 in Diagnosis and Follow-Up of Trypanosoma brucei gambiense Sleeping Sickness: Lessons from the Field in Angola. BIOMED RESEARCH INTERNATIONAL 2019; 2019:6070176. [PMID: 31886231 PMCID: PMC6914994 DOI: 10.1155/2019/6070176] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 04/24/2019] [Revised: 09/10/2019] [Accepted: 10/08/2019] [Indexed: 11/26/2022]
Abstract
Human African Trypanosomiasis may become manageable in the next decade with fexinidazole. However, currently stage diagnosis remains difficult to implement in the field and requires a lumbar puncture. Our study of an Angolan cohort of T. b. gambiense-infected patients used other staging criteria than those recommended by the WHO. We compared WHO criteria (cell count and parasite identification in the CSF) with two biomarkers (neopterin and CXCL-13) which have proven potential to diagnose disease stage or relapse. Biological, clinical, and neurological data were analysed from a cohort of 83 patients. A neopterin concentration below 15.5 nmol/L in the CSF denoted patients with stage 1 disease, and a concentration above 60.31 nmol/L characterized patients with advanced stage 2 (trypanosomes in CSF and/or cytorachia higher than 20 cells) disease. CXCL-13 levels below 91.208 pg/mL denoted patients with stage 1 disease, and levels of CXCL-13 above 395.45 pg/mL denoted patients with advanced stage 2 disease. Values between these cut-offs may represent patients with intermediate stage disease. Our work supports the existence of an intermediate stage in HAT, and CXCL-13 and neopterin levels may help to characterize it.
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Onyilagha C, Kuriakose S, Ikeogu N, Kung SKP, Uzonna JE. NK Cells Are Critical for Optimal Immunity to Experimental Trypanosoma congolense Infection. THE JOURNAL OF IMMUNOLOGY 2019; 203:964-971. [PMID: 31243088 DOI: 10.4049/jimmunol.1900103] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/28/2019] [Accepted: 06/10/2019] [Indexed: 02/07/2023]
Abstract
NK cells are key innate immune cells that play critical roles in host defense. Although NK cells have been shown to regulate immunity to some infectious diseases, their role in immunity to Trypanosoma congolense has not been investigated. NK cells are vital sources of IFN-γ and TNF-α; two key cytokines that are known to play important roles in resistance to African trypanosomes. In this article, we show that infection with T. congolense leads to increased levels of activated and functional NK cells in multiple tissue compartments. Systemic depletion of NK cells with anti-NK1.1 mAb led to increased parasitemia, which was accompanied by significant reduction in IFN-γ production by immune cells in the spleens and liver of infected mice. Strikingly, infected NFIL3-/- mice (which genetically lack NK cell development and function) on the normally resistant background were highly susceptible to T. congolense infection. These mice developed fulminating and uncontrolled parasitemia and died significantly earlier (13 ± 1 d) than their wild-type control mice (106 ± 26 d). The enhanced susceptibility of NFIL3-/- mice to infection was accompanied by significantly impaired cytokine (IFN-γ and TNF-α) response by CD3+ T cells in the spleens and liver. Adoptive transfer of NK cells into NFIL3-/- mice before infection rescued them from acute death in a perforin-dependent manner. Collectively, these studies show that NK cells are critical for optimal resistance to T. congolense, and its deficiency leads to enhanced susceptibility in infected mice.
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Affiliation(s)
- Chukwunonso Onyilagha
- Department of Immunology, Max Rady College of Medicine, Rady Faculty of Health Sciences, University of Manitoba, Winnipeg, Manitoba R3E 0T5, Canada; and
| | - Shiby Kuriakose
- Department of Immunology, Max Rady College of Medicine, Rady Faculty of Health Sciences, University of Manitoba, Winnipeg, Manitoba R3E 0T5, Canada; and
| | - Nnamdi Ikeogu
- Department of Immunology, Max Rady College of Medicine, Rady Faculty of Health Sciences, University of Manitoba, Winnipeg, Manitoba R3E 0T5, Canada; and
| | - Sam K P Kung
- Department of Immunology, Max Rady College of Medicine, Rady Faculty of Health Sciences, University of Manitoba, Winnipeg, Manitoba R3E 0T5, Canada; and
| | - Jude E Uzonna
- Department of Immunology, Max Rady College of Medicine, Rady Faculty of Health Sciences, University of Manitoba, Winnipeg, Manitoba R3E 0T5, Canada; and .,Department of Medical Microbiology, Max Rady College of Medicine, Rady Faculty of Health Sciences, University of Manitoba, Winnipeg, Manitoba R3E 0J9, Canada
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20
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In vitro antiprotozoal activity of some medicinal plants against sleeping sickness, Chagas disease and leishmaniasis. Future Med Chem 2018; 10:2607-2617. [PMID: 30511591 DOI: 10.4155/fmc-2018-0180] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/17/2022] Open
Abstract
AIM Antiprotozoal activity of 36 medicinal plants was evaluated. MATERIALS & METHODS In vitro potency against Trypanosoma brucei brucei, T. b. rhodesiense, T. cruzi and Leishmania infantum beside cytotoxicity on MRC-5 fibroblasts were determined. RESULTS & CONCLUSION Maytenus parviflora showed the highest activity against T. b. brucei (IC50 of 0.6 μg/ml) and T. b. rhodesiense (IC50 of 0.5 μg/ml) with low cytotoxicity (CC50 of 30 μg/ml). Saussurea costus and Commiphora wightii, showed pronounced potency against T. cruzi with an IC50 of 3.6 and 2.5 μg/ml, respectively. Jatropha pelargonifolia and Solanum villosum exhibited pronounced activity toward L. infantum with an IC50 of 3.2 and 2.0 μg/ml, respectively. M. parviflora, S. costus, C. wightii, J. pelargonifolia and S. villosum showed relevant selectivity.
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21
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Monti L, Wang SC, Oukoloff K, Smith AB, Brunden KR, Caffrey CR, Ballatore C. Brain-Penetrant Triazolopyrimidine and Phenylpyrimidine Microtubule Stabilizers as Potential Leads to Treat Human African Trypanosomiasis. ChemMedChem 2018; 13:1751-1754. [PMID: 29969537 DOI: 10.1002/cmdc.201800404] [Citation(s) in RCA: 15] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/14/2018] [Indexed: 11/07/2022]
Abstract
In vitro whole-organism screens of Trypanosoma brucei with representative examples of brain-penetrant microtubule (MT)-stabilizing agents identified lethal triazolopyrimidines and phenylpyrimidines with sub-micromolar potency. In mammalian cells, these antiproliferative compounds disrupt MT integrity and decrease total tubulin levels. Their parasiticidal potency, combined with their generally favorable pharmacokinetic properties, which include oral bioavailability and brain penetration, suggest that these compounds are potential leads against human African trypanosomiasis.
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Affiliation(s)
- Ludovica Monti
- Center for Discovery and Innovation in Parasitic Diseases, Skaggs School of Pharmacy and Pharmaceutical Sciences, University of California San Diego, 9500 Gilman Drive, La Jolla, CA, 92093, USA
| | - Steven C Wang
- Center for Discovery and Innovation in Parasitic Diseases, Skaggs School of Pharmacy and Pharmaceutical Sciences, University of California San Diego, 9500 Gilman Drive, La Jolla, CA, 92093, USA
| | - Killian Oukoloff
- Center for Discovery and Innovation in Parasitic Diseases, Skaggs School of Pharmacy and Pharmaceutical Sciences, University of California San Diego, 9500 Gilman Drive, La Jolla, CA, 92093, USA
| | - Amos B Smith
- Department of Chemistry, School of Arts and Sciences, University of Pennsylvania, 231 South 34th Street, Philadelphia, PA, 19104-6323, USA
| | - Kurt R Brunden
- Center for Neurodegenerative Disease Research, Perelman School of Medicine, University of Pennsylvania, 3600 Spruce Street, Philadelphia, PA, 19104-6323, USA
| | - Conor R Caffrey
- Center for Discovery and Innovation in Parasitic Diseases, Skaggs School of Pharmacy and Pharmaceutical Sciences, University of California San Diego, 9500 Gilman Drive, La Jolla, CA, 92093, USA
| | - Carlo Ballatore
- Center for Discovery and Innovation in Parasitic Diseases, Skaggs School of Pharmacy and Pharmaceutical Sciences, University of California San Diego, 9500 Gilman Drive, La Jolla, CA, 92093, USA
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22
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Onyilagha C, Kuriakose S, Ikeogu N, Jia P, Uzonna J. Myeloid-Derived Suppressor Cells Contribute to Susceptibility to Trypanosoma congolense Infection by Suppressing CD4 + T Cell Proliferation and IFN-γ Production. THE JOURNAL OF IMMUNOLOGY 2018; 201:507-515. [PMID: 29898961 DOI: 10.4049/jimmunol.1800180] [Citation(s) in RCA: 12] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/12/2018] [Accepted: 05/14/2018] [Indexed: 01/07/2023]
Abstract
Myeloid-derived suppressor cells (MDSCs) are a heterogeneous population of bone marrow-derived myeloid cells that have immune-suppressive activities. These cells have been reported to suppress T cell immunity against tumors as well as in some parasitic and bacterial infections. However, their role during Trypanosoma congolense infection has not been studied. Given that immunosuppression is a hallmark of African trypanosomiasis, we investigated the role of MDSCs in immunity to T. congolense infection. We found increased numbers of MDSCs in the spleen and liver of infected mice, which correlated with increased parasitemia. Depletion of MDSCs significantly increased the percentage of proliferating and IFN-γ-producing CD4+ T cells from the spleen of T. congolense-infected mice. Furthermore, MDSCs from T. congolense-infected mice directly suppressed CD4+ T cell proliferation in a coculture setting. This suppressive effect was abolished by the arginase-1 inhibitor, Nω-hydroxy-nor-l-arginine (nor-NOHA), indicating that MDSCs suppress CD4+ T cell proliferation and function in an arginase-1-dependent manner. Indeed, depletion of MDSCs during infection led to control of the first wave of parasitemia and prolonged survival of infected mice. This was also associated with increased CD4+ T cell proliferation and IFN-γ production. Taken together, our findings identify an important role of MDSCs in the pathogenesis of experimental T. congolense infection via suppression of T cell proliferative and effector cytokine responses in an arginase-1-dependent manner.
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Affiliation(s)
- Chukwunonso Onyilagha
- Department of Immunology, Max Rady College of Medicine, Rady Faculty of Health Sciences, University of Manitoba, Winnipeg, Manitoba R3E 0T5, Canada; and
| | - Shiby Kuriakose
- Department of Immunology, Max Rady College of Medicine, Rady Faculty of Health Sciences, University of Manitoba, Winnipeg, Manitoba R3E 0T5, Canada; and
| | - Nnamdi Ikeogu
- Department of Immunology, Max Rady College of Medicine, Rady Faculty of Health Sciences, University of Manitoba, Winnipeg, Manitoba R3E 0T5, Canada; and
| | - Ping Jia
- Department of Immunology, Max Rady College of Medicine, Rady Faculty of Health Sciences, University of Manitoba, Winnipeg, Manitoba R3E 0T5, Canada; and
| | - Jude Uzonna
- Department of Immunology, Max Rady College of Medicine, Rady Faculty of Health Sciences, University of Manitoba, Winnipeg, Manitoba R3E 0T5, Canada; and .,Department of Medical Microbiology and Infectious Diseases, Max Rady College of Medicine, Rady Faculty of Health Sciences, University of Manitoba, Winnipeg, Manitoba R3E 0J9, Canada
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23
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Steketee PC, Vincent IM, Achcar F, Giordani F, Kim DH, Creek DJ, Freund Y, Jacobs R, Rattigan K, Horn D, Field MC, MacLeod A, Barrett MP. Benzoxaborole treatment perturbs S-adenosyl-L-methionine metabolism in Trypanosoma brucei. PLoS Negl Trop Dis 2018; 12:e0006450. [PMID: 29758036 PMCID: PMC5976210 DOI: 10.1371/journal.pntd.0006450] [Citation(s) in RCA: 25] [Impact Index Per Article: 4.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/01/2017] [Revised: 05/30/2018] [Accepted: 04/15/2018] [Indexed: 11/21/2022] Open
Abstract
The parasitic protozoan Trypanosoma brucei causes Human African Trypanosomiasis and Nagana in other mammals. These diseases present a major socio-economic burden to large areas of sub-Saharan Africa. Current therapies involve complex and toxic regimens, which can lead to fatal side-effects. In addition, there is emerging evidence for drug resistance. AN5568 (SCYX-7158) is a novel benzoxaborole class compound that has been selected as a lead compound for the treatment of HAT, and has demonstrated effective clearance of both early and late stage trypanosomiasis in vivo. The compound is currently awaiting phase III clinical trials and could lead to a novel oral therapeutic for the treatment of HAT. However, the mode of action of AN5568 in T. brucei is unknown. This study aimed to investigate the mode of action of AN5568 against T. brucei, using a combination of molecular and metabolomics-based approaches.Treatment of blood-stage trypanosomes with AN5568 led to significant perturbations in parasite metabolism. In particular, elevated levels of metabolites involved in the metabolism of S-adenosyl-L-methionine, an essential methyl group donor, were found. Further comparative metabolomic analyses using an S-adenosyl-L-methionine-dependent methyltransferase inhibitor, sinefungin, showed the presence of several striking metabolic phenotypes common to both treatments. Furthermore, several metabolic changes in AN5568 treated parasites resemble those invoked in cells treated with a strong reducing agent, dithiothreitol, suggesting redox imbalances could be involved in the killing mechanism.
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Affiliation(s)
- Pieter C. Steketee
- Wellcome Centre for Molecular Parasitology, Institute of Infection, Immunity and Inflammation, College of Medical, Veterinary and Life Sciences, University of Glasgow, Glasgow, United Kingdom
| | - Isabel M. Vincent
- Wellcome Centre for Molecular Parasitology, Institute of Infection, Immunity and Inflammation, College of Medical, Veterinary and Life Sciences, University of Glasgow, Glasgow, United Kingdom
| | - Fiona Achcar
- Wellcome Centre for Molecular Parasitology, Institute of Infection, Immunity and Inflammation, College of Medical, Veterinary and Life Sciences, University of Glasgow, Glasgow, United Kingdom
| | - Federica Giordani
- Wellcome Centre for Molecular Parasitology, Institute of Infection, Immunity and Inflammation, College of Medical, Veterinary and Life Sciences, University of Glasgow, Glasgow, United Kingdom
| | - Dong-Hyun Kim
- Centre for Analytical Bioscience, Division of Molecular and Cellular Sciences, School of Pharmacy, The University of Nottingham, Nottingham, United Kingdom
| | - Darren J. Creek
- Department of Biochemistry and Molecular Biology, Drug Delivery Disposition and Dynamics, Monash Institute of Pharmaceutical Sciences, Monash University, Parkville, Victoria, Australia
| | - Yvonne Freund
- Anacor Pharmaceuticals, Inc., Palo Alto, California, United States of America
| | - Robert Jacobs
- Anacor Pharmaceuticals, Inc., Palo Alto, California, United States of America
| | - Kevin Rattigan
- Wellcome Centre for Molecular Parasitology, Institute of Infection, Immunity and Inflammation, College of Medical, Veterinary and Life Sciences, University of Glasgow, Glasgow, United Kingdom
| | - David Horn
- Wellcome Centre for Anti-Infectives Research, School of Life Sciences, University of Dundee, Dundee, United Kingdom
| | - Mark C. Field
- Wellcome Centre for Anti-Infectives Research, School of Life Sciences, University of Dundee, Dundee, United Kingdom
| | - Annette MacLeod
- Wellcome Centre for Molecular Parasitology, Institute of Infection, Immunity and Inflammation, College of Medical, Veterinary and Life Sciences, University of Glasgow, Glasgow, United Kingdom
| | - Michael P. Barrett
- Wellcome Centre for Molecular Parasitology, Institute of Infection, Immunity and Inflammation, College of Medical, Veterinary and Life Sciences, University of Glasgow, Glasgow, United Kingdom
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24
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West RA, Cunningham T, Pennicott LE, Rao SPS, Ward SE. Toward More Drug Like Inhibitors of Trypanosome Alternative Oxidase. ACS Infect Dis 2018; 4:592-604. [PMID: 29353481 DOI: 10.1021/acsinfecdis.7b00218] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Abstract
New tools are required to ensure the adequate control of the neglected tropical disease human African trypanosomiasis. Annual reports of infection have recently fallen to fewer than 5000 cases per year; however, current therapies are hard to administer and have safety concerns and, hence, are far from ideal. Trypanosome alternative oxidase is an exciting target for controlling the infection; it is unique to the parasite, and inhibition of this enzyme with the natural product ascofuranone has shown to clear in vivo infections. We report the synthesis and associated structure activity relationships of inhibitors based upon this natural product with correlation to T. b. brucei growth inhibition in an attempt to generate molecules that possess improved physicochemical properties and potential for use as new treatments for human African trypanosomiasis.
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Affiliation(s)
- Ryan A. West
- Sussex Drug Discovery Centre, University of Sussex, Brighton, BN1 9QJ, United Kingdom
| | - Thomas Cunningham
- Sussex Drug Discovery Centre, University of Sussex, Brighton, BN1 9QJ, United Kingdom
| | - Lewis E. Pennicott
- Sussex Drug Discovery Centre, University of Sussex, Brighton, BN1 9QJ, United Kingdom
| | - Srinivasa P. S. Rao
- Novartis Institutes for Tropical Diseases, 5300 Chiron Way, Emeryville, California 94608-2916, United States
| | - Simon E. Ward
- Sussex Drug Discovery Centre, University of Sussex, Brighton, BN1 9QJ, United Kingdom
- Medicines Discovery Institute, Cardiff University, Park Place, Cardiff, CF10 3AT, United Kingdom
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25
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Alderton S, Macleod ET, Anderson NE, Palmer G, Machila N, Simuunza M, Welburn SC, Atkinson PM. An agent-based model of tsetse fly response to seasonal climatic drivers: Assessing the impact on sleeping sickness transmission rates. PLoS Negl Trop Dis 2018; 12:e0006188. [PMID: 29425200 PMCID: PMC5806852 DOI: 10.1371/journal.pntd.0006188] [Citation(s) in RCA: 12] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/17/2017] [Accepted: 12/22/2017] [Indexed: 11/18/2022] Open
Abstract
BACKGROUND This paper presents the development of an agent-based model (ABM) to incorporate climatic drivers which affect tsetse fly (G. m. morsitans) population dynamics, and ultimately disease transmission. The model was used to gain a greater understanding of how tsetse populations fluctuate seasonally, and investigate any response observed in Trypanosoma brucei rhodesiense human African trypanosomiasis (rHAT) disease transmission, with a view to gaining a greater understanding of disease dynamics. Such an understanding is essential for the development of appropriate, well-targeted mitigation strategies in the future. METHODS The ABM was developed to model rHAT incidence at a fine spatial scale along a 75 km transect in the Luangwa Valley, Zambia. The model incorporates climatic factors that affect pupal mortality, pupal development, birth rate, and death rate. In combination with fine scale demographic data such as ethnicity, age and gender for the human population in the region, as well as an animal census and a sample of daily routines, we create a detailed, plausible simulation model to explore tsetse population and disease transmission dynamics. RESULTS The seasonally-driven model suggests that the number of infections reported annually in the simulation is likely to be a reasonable representation of reality, taking into account the high levels of under-detection observed. Similar infection rates were observed in human (0.355 per 1000 person-years (SE = 0.013)), and cattle (0.281 per 1000 cattle-years (SE = 0.025)) populations, likely due to the sparsity of cattle close to the tsetse interface. The model suggests that immigrant tribes and school children are at greatest risk of infection, a result that derives from the bottom-up nature of the ABM and conditioning on multiple constraints. This result could not be inferred using alternative population-level modelling approaches. CONCLUSIONS In producing a model which models the tsetse population at a very fine resolution, we were able to analyse and evaluate specific elements of the output, such as pupal development and the progression of the teneral population, allowing the development of our understanding of the tsetse population as a whole. This is an important step in the production of a more accurate transmission model for rHAT which can, in turn, help us to gain a greater understanding of the transmission system as a whole.
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Affiliation(s)
- Simon Alderton
- Geography and Environment, Faculty of Social and Human Sciences, University of Southampton, Southampton, United Kingdom
- Lancaster Environment Centre, Lancaster University, Lancaster, United Kingdom
- Centre for Health Informatics, Computing and Statistics (CHICAS), Lancaster Medical School, Lancaster University, Lancaster, United Kingdom
- * E-mail:
| | - Ewan T. Macleod
- Division of Infection and Pathway Medicine, Biomedical Sciences, Edinburgh Medical School, College of Medicine and Veterinary Medicine, The University of Edinburgh, Edinburgh, United Kingdom
| | - Neil E. Anderson
- The Royal (Dick) School of Veterinary Studies and the Roslin Institute, University of Edinburgh, Roslin, United Kingdom
| | - Gwen Palmer
- Independent Researcher, Leyland, Lancashire, United Kingdom
| | - Noreen Machila
- Division of Infection and Pathway Medicine, Biomedical Sciences, Edinburgh Medical School, College of Medicine and Veterinary Medicine, The University of Edinburgh, Edinburgh, United Kingdom
- Department of Disease Control, School of Veterinary Medicine, University of Zambia, Lusaka, Zambia
| | - Martin Simuunza
- Department of Disease Control, School of Veterinary Medicine, University of Zambia, Lusaka, Zambia
| | - Susan C. Welburn
- Division of Infection and Pathway Medicine, Biomedical Sciences, Edinburgh Medical School, College of Medicine and Veterinary Medicine, The University of Edinburgh, Edinburgh, United Kingdom
| | - Peter M. Atkinson
- Geography and Environment, Faculty of Social and Human Sciences, University of Southampton, Southampton, United Kingdom
- Lancaster Environment Centre, Lancaster University, Lancaster, United Kingdom
- Centre for Health Informatics, Computing and Statistics (CHICAS), Lancaster Medical School, Lancaster University, Lancaster, United Kingdom
- School of Geography, Archaeology and Palaeoecology, Queen's University Belfast, Northern Ireland, United Kingdom
- State Key Laboratory of Resources and Environmental Information System, Institute of Geographic Sciences and Natural Resources Research, Chinese Academy of Sciences, Beijing, China
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26
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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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27
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Wiedemar N, Graf FE, Zwyer M, Ndomba E, Kunz Renggli C, Cal M, Schmidt RS, Wenzler T, Mäser P. Beyond immune escape: a variant surface glycoprotein causes suramin resistance in Trypanosoma brucei. Mol Microbiol 2017; 107:57-67. [PMID: 28963732 DOI: 10.1111/mmi.13854] [Citation(s) in RCA: 19] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 09/27/2017] [Indexed: 11/27/2022]
Abstract
Suramin is one of the first drugs developed in a medicinal chemistry program (Bayer, 1916), and it is still the treatment of choice for the hemolymphatic stage of African sleeping sickness caused by Trypanosoma brucei rhodesiense. Cellular uptake of suramin occurs by endocytosis, and reverse genetic studies with T. b. brucei have linked downregulation of the endocytic pathway to suramin resistance. Here we show that forward selection for suramin resistance in T. brucei spp. cultures is fast, highly reproducible and linked to antigenic variation. Bloodstream-form trypanosomes are covered by a dense coat of variant surface glycoprotein (VSG), which protects them from their mammalian hosts' immune defenses. Each T. brucei genome contains over 2000 different VSG genes, but only one is expressed at a time. An expression switch to one particular VSG, termed VSGSur , correlated with suramin resistance. Reintroduction of the originally expressed VSG gene in resistant T. brucei restored suramin susceptibility. This is the first report of a link between antigenic variation and drug resistance in African trypanosomes.
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Affiliation(s)
- Natalie Wiedemar
- Swiss Tropical and Public Health Institute, Basel CH-4002, Switzerland.,University of Basel, Basel CH-4001, Switzerland
| | - Fabrice E Graf
- Swiss Tropical and Public Health Institute, Basel CH-4002, Switzerland.,University of Basel, Basel CH-4001, Switzerland
| | - Michaela Zwyer
- Swiss Tropical and Public Health Institute, Basel CH-4002, Switzerland.,University of Basel, Basel CH-4001, Switzerland
| | - Emiliana Ndomba
- Swiss Tropical and Public Health Institute, Basel CH-4002, Switzerland.,University of Basel, Basel CH-4001, Switzerland
| | - Christina Kunz Renggli
- Swiss Tropical and Public Health Institute, Basel CH-4002, Switzerland.,University of Basel, Basel CH-4001, Switzerland
| | - Monica Cal
- Swiss Tropical and Public Health Institute, Basel CH-4002, Switzerland.,University of Basel, Basel CH-4001, Switzerland
| | - Remo S Schmidt
- Swiss Tropical and Public Health Institute, Basel CH-4002, Switzerland.,University of Basel, Basel CH-4001, Switzerland
| | - Tanja Wenzler
- Swiss Tropical and Public Health Institute, Basel CH-4002, Switzerland.,University of Basel, Basel CH-4001, Switzerland
| | - Pascal Mäser
- Swiss Tropical and Public Health Institute, Basel CH-4002, Switzerland.,University of Basel, Basel CH-4001, Switzerland
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28
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Abstract
In the last 2 decades, renewed attention to neglected tropical diseases (NTDs) has spurred the development of antiparasitic agents, especially in light of emerging drug resistance. The need for new drugs has required in vitro screening methods using parasite culture. Furthermore, clinical laboratories sought to correlate in vitro susceptibility methods with treatment outcomes, most notably with malaria. Parasites with their various life cycles present greater complexity than bacteria, for which standardized susceptibility methods exist. This review catalogs the state-of-the-art methodologies used to evaluate the effects of drugs on key human parasites from the point of view of drug discovery as well as the need for laboratory methods that correlate with clinical outcomes.
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29
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Ettari R, Previti S, Cosconati S, Maiorana S, Schirmeister T, Grasso S, Zappalà M. Development of novel 1,4-benzodiazepine-based Michael acceptors as antitrypanosomal agents. Bioorg Med Chem Lett 2016; 26:3453-6. [DOI: 10.1016/j.bmcl.2016.06.047] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/26/2016] [Revised: 06/15/2016] [Accepted: 06/16/2016] [Indexed: 10/21/2022]
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30
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Sun YN, No JH, Lee GY, Li W, Yang SY, Yang G, Schmidt TJ, Kang JS, Kim YH. Phenolic Constituents of Medicinal Plants with Activity against Trypanosoma brucei. Molecules 2016; 21:480. [PMID: 27077842 PMCID: PMC6273235 DOI: 10.3390/molecules21040480] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/24/2016] [Revised: 04/01/2016] [Accepted: 04/01/2016] [Indexed: 11/24/2022] Open
Abstract
Neglected tropical diseases (NTDs) affect over one billion people all over the world. These diseases are classified as neglected because they impact populations in areas with poor financial conditions and hence do not attract sufficient research investment. Human African Trypanosomiasis (HAT or sleeping sickness), caused by the parasite Trypanosoma brucei, is one of the NTDs. The current therapeutic interventions for T. brucei infections often have toxic side effects or require hospitalization so that they are not available in the rural environments where HAT occurs. Furthermore, parasite resistance is increasing, so that there is an urgent need to identify novel lead compounds against this infection. Recognizing the wide structural diversity of natural products, we desired to explore and identify novel antitrypanosomal chemotypes from a collection of natural products obtained from plants. In this study, 440 pure compounds from various medicinal plants were tested against T. brucei by in a screening using whole cell in vitro assays. As the result, twenty-two phenolic compounds exhibited potent activity against cultures of T. brucei. Among them, eight compounds—4, 7, 11, 14, 15, 18, 20, and 21—showed inhibitory activity against T. brucei, with IC50 values below 5 µM, ranging from 0.52 to 4.70 μM. Based on these results, we attempt to establish some general trends with respect to structure-activity relationships, which indicate that further investigation and optimization of these derivatives might enable the preparation of potentially useful compounds for treating HAT.
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Affiliation(s)
- Ya Nan Sun
- College of Pharmacy, Chungnam National University, Daejeon 305-764, Korea.
| | - Joo Hwan No
- Leishmania Research Laboratory, Institut Pasteur Korea, 696 Sampyeong-dong, Bundang-gu, Seongnam-si, Gyeonggi 463-400, Korea.
| | - Ga Young Lee
- College of Pharmacy, Chungnam National University, Daejeon 305-764, Korea.
| | - Wei Li
- School of Biotechnology, Yeungnam University, Gyeongsan, Gyeongbuk 712-749, Korea.
| | - Seo Young Yang
- College of Pharmacy, Chungnam National University, Daejeon 305-764, Korea.
| | - Gyongseon Yang
- Leishmania Research Laboratory, Institut Pasteur Korea, 696 Sampyeong-dong, Bundang-gu, Seongnam-si, Gyeonggi 463-400, Korea.
| | - Thomas J Schmidt
- Institute of Pharmaceutical Biology and Phytochemistry (IPBP), University of Münster, PharmaCampus, Corrensstrasse 48, D-48149 Münster, Germany.
| | - Jong Seong Kang
- College of Pharmacy, Chungnam National University, Daejeon 305-764, Korea.
| | - Young Ho Kim
- College of Pharmacy, Chungnam National University, Daejeon 305-764, Korea.
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31
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In Silico Investigation of Flavonoids as Potential Trypanosomal Nucleoside Hydrolase Inhibitors. Adv Bioinformatics 2015; 2015:826047. [PMID: 26640486 PMCID: PMC4660014 DOI: 10.1155/2015/826047] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/27/2015] [Revised: 10/17/2015] [Accepted: 10/20/2015] [Indexed: 11/24/2022] Open
Abstract
Human African Trypanosomiasis is endemic to 37 countries of sub-Saharan Africa. It is caused by two related species of Trypanosoma brucei. Current therapies suffer from resistance and public accessibility of expensive medicines. Finding safer and effective therapies of natural origin is being extensively explored worldwide. Pentamidine is the only available therapy for inhibiting the P2 adenosine transporter involved in the purine salvage pathway of the trypanosomatids. The objective of the present study is to use computational studies for the investigation of the probable trypanocidal mechanism of flavonoids. Docking experiments were carried out on eight flavonoids of varying level of hydroxylation, namely, flavone, 5-hydroxyflavone, 7-hydroxyflavone, chrysin, apigenin, kaempferol, fisetin, and quercetin. Using AutoDock 4.2, these compounds were tested for their affinity towards inosine-adenosine-guanosine nucleoside hydrolase and the inosine-guanosine nucleoside hydrolase, the major enzymes of the purine salvage pathway. Our results showed that all of the eight tested flavonoids showed high affinities for both hydrolases (lowest free binding energy ranging from −10.23 to −7.14 kcal/mol). These compounds, especially the hydroxylated derivatives, could be further studied as potential inhibitors of the nucleoside hydrolases.
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32
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Keating J, Yukich JO, Sutherland CS, Woods G, Tediosi F. Human African trypanosomiasis prevention, treatment and control costs: a systematic review. Acta Trop 2015; 150:4-13. [PMID: 26056739 DOI: 10.1016/j.actatropica.2015.06.003] [Citation(s) in RCA: 33] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/31/2015] [Revised: 06/02/2015] [Accepted: 06/03/2015] [Indexed: 11/18/2022]
Abstract
The control and eventual elimination of human African trypanosomiasis (HAT) requires the expansion of current control and surveillance activities. A systematic review of the published literature on the costs of HAT prevention, treatment, and control, in addition to the economic burden, was conducted. All studies that contained primary or secondary data on costs of prevention, treatment and control were considered, resulting in the inclusion of 42 papers. The geographically focal nature of the disease and a lack of standardization in the cost data limit the usefulness of the available information for making generalizations across diverse settings. More recent information on the costs of treatment and control interventions for HAT is needed to provide accurate information for analyses and planning. The cost information contained herein can be used to inform rational decision making in control and elimination programs, and to assess potential synergies with existing vector-borne disease control programs, but programs would benefit significantly from new cost data collection.
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Affiliation(s)
- Joseph Keating
- Center for Applied Malaria Research and Evaluation, Tulane University School of Public Health and Tropical Medicine, 1440 Canal Street, Suite 2200, New Orleans, LA 70112, USA; Department of Tropical Medicine, Tulane University School of Public Health and Tropical Medicine, 1440 Canal Street, Suite 2309, New Orleans, LA 70112, USA.
| | - Joshua O Yukich
- Center for Applied Malaria Research and Evaluation, Tulane University School of Public Health and Tropical Medicine, 1440 Canal Street, Suite 2200, New Orleans, LA 70112, USA; Department of Tropical Medicine, Tulane University School of Public Health and Tropical Medicine, 1440 Canal Street, Suite 2309, New Orleans, LA 70112, USA.
| | - C Simone Sutherland
- Department of Epidemiologyand Public Health, Swiss Tropicaland Public Health Institute, Socinstrasse 57, 4002 Basel, Switzerland; University of Basel, Switzerland.
| | - Geordie Woods
- Sightsavers, 35 Perrymount Road, Haywards Heath, West Sussex, RH16 3BW, UK.
| | - Fabrizio Tediosi
- Department of Epidemiologyand Public Health, Swiss Tropicaland Public Health Institute, Socinstrasse 57, 4002 Basel, Switzerland; University of Basel, Switzerland; Centre for Research on Health and Social Care Management (CERGAS), UniversitàBocconi, Milan, Italy.
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33
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Alderton S, Noble J, Schaten K, Welburn SC, Atkinson PM. Exploiting Human Resource Requirements to Infer Human Movement Patterns for Use in Modelling Disease Transmission Systems: An Example from Eastern Province, Zambia. PLoS One 2015; 10:e0139505. [PMID: 26421926 PMCID: PMC4589342 DOI: 10.1371/journal.pone.0139505] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/04/2015] [Accepted: 09/12/2015] [Indexed: 11/18/2022] Open
Abstract
In this research, an agent-based model (ABM) was developed to generate human movement routes between homes and water resources in a rural setting, given commonly available geospatial datasets on population distribution, land cover and landscape resources. ABMs are an object-oriented computational approach to modelling a system, focusing on the interactions of autonomous agents, and aiming to assess the impact of these agents and their interactions on the system as a whole. An A* pathfinding algorithm was implemented to produce walking routes, given data on the terrain in the area. A* is an extension of Dijkstra’s algorithm with an enhanced time performance through the use of heuristics. In this example, it was possible to impute daily activity movement patterns to the water resource for all villages in a 75 km long study transect across the Luangwa Valley, Zambia, and the simulated human movements were statistically similar to empirical observations on travel times to the water resource (Chi-squared, 95% confidence interval). This indicates that it is possible to produce realistic data regarding human movements without costly measurement as is commonly achieved, for example, through GPS, or retrospective or real-time diaries. The approach is transferable between different geographical locations, and the product can be useful in providing an insight into human movement patterns, and therefore has use in many human exposure-related applications, specifically epidemiological research in rural areas, where spatial heterogeneity in the disease landscape, and space-time proximity of individuals, can play a crucial role in disease spread.
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Affiliation(s)
- Simon Alderton
- Institute of Complex System Simulation, School of Electronics and Computer Science, University of Southampton, Southampton, United Kingdom
- Geography and Environment, Faculty of Social and Human Sciences, University of Southampton, Southampton, United Kingdom
- * E-mail:
| | - Jason Noble
- Institute of Complex System Simulation, School of Electronics and Computer Science, University of Southampton, Southampton, United Kingdom
| | - Kathrin Schaten
- Division of Pathway Medicine and Centre for Infectious Diseases, School of Biomedical Sciences, College of Medicine and Veterinary Medicine, The University of Edinburgh, Edinburgh, United Kingdom
| | - Susan C. Welburn
- Division of Pathway Medicine and Centre for Infectious Diseases, School of Biomedical Sciences, College of Medicine and Veterinary Medicine, The University of Edinburgh, Edinburgh, United Kingdom
| | - Peter M. Atkinson
- Faculty of Science and Technology, Engineering Building, Lancaster University, Lancaster, United Kingdom
- Faculty of Geosciences, University of Utrecht, Heidelberglaan 2, 3584 CS Utrecht, The Netherlands
- School of Geography, Archaeology and Palaeoecology, Queen’s University Belfast, Northern Ireland, United Kingdom
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Mpanya A, Hendrickx D, Baloji S, Lumbala C, da Luz RI, Boelaert M, Lutumba P. From health advice to taboo: community perspectives on the treatment of sleeping sickness in the Democratic Republic of Congo, a qualitative study. PLoS Negl Trop Dis 2015; 9:e0003686. [PMID: 25856578 PMCID: PMC4391751 DOI: 10.1371/journal.pntd.0003686] [Citation(s) in RCA: 16] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/20/2014] [Accepted: 03/07/2015] [Indexed: 12/14/2022] Open
Abstract
Background Socio-cultural and economic factors constitute real barriers for uptake of screening and treatment of Human African Trypanosomiasis (HAT) in the Democratic Republic of Congo (DRC). Better understanding and addressing these barriers may enhance the effectiveness of HAT control. Methods We performed a qualitative study consisting of semi-structured interviews and focus group discussions in the Bandundu and Kasaï Oriental provinces, two provinces lagging behind in the HAT elimination effort. Our study population included current and former HAT patients, as well as healthcare providers and program managers of the national HAT control program. All interviews and discussions were voice recorded on a digital device and data were analysed with the ATLAS.ti software. Findings Health workers and community members quoted a number of prohibitions that have to be respected for six months after HAT treatment: no work, no sexual intercourse, no hot food, not walking in the sun. Violating these restrictions is believed to cause serious, and sometimes deadly, complications. These strong prohibitions are well-known by the community and lead some people to avoid HAT screening campaigns, for fear of having to observe such taboos in case of diagnosis. Discussion The restrictions originally aimed to mitigate the severe adverse effects of the melarsoprol regimen, but are not evidence-based and became obsolete with the new safer drugs. Correct health information regarding HAT treatment is essential. Health providers should address the perspective of the community in a constant dialogue to keep abreast of unintended transformations of meaning. The principal strategy for the control of HAT is based on early detection and prompt treatment of identified cases. A range of taboos are associated with HAT treatment in DRC. The origin of these taboos is not well understood. These taboos constitute major issues for patients and their families, lead to huge social pressure from the community on HAT patients and add in themselves to the burden caused by the disease itself. The aim of this study is to document the origin of these taboos and other cultural factors that are associated with HAT treatment, since an improved understanding of these factors and their implications may lead to strategies for improved community adherence to HAT screening and treatment. We found that the taboos are associated with the melarsoprol toxicity and have been established empirically following past interactions between healthcare providers and communities. The prohibitions started as simple instructions provided by healthcare providers about the management of HAT cases, but over time evolved into the community-based taboos we observe now. Use of less toxic treatment alternatives for HAT, dissemination of correct information regarding HAT treatment regimens, possible occurrence of adverse events and their cause would be beneficial to HAT control.
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Affiliation(s)
- Alain Mpanya
- Programme National de Lutte contre la Trypanosomiase Humaine Africaine, Kinshasa, Democratic Republic of Congo
- Institute of Tropical Medicine, Antwerp, Belgium
- * E-mail:
| | - David Hendrickx
- Institute of Tropical Medicine, Antwerp, Belgium
- Telethon Kids Institute, University of Western Australia, Perth, Western Australia, Australia
| | - Sylvain Baloji
- Programme National de Lutte contre la Trypanosomiase Humaine Africaine, Kinshasa, Democratic Republic of Congo
- Université Pédagogique Nationale, Kinshasa, Democratic Republic of Congo
| | - Crispin Lumbala
- Programme National de Lutte contre la Trypanosomiase Humaine Africaine, Kinshasa, Democratic Republic of Congo
| | | | | | - Pascal Lutumba
- Institut National de Recherche Biomédicale, Kinshasa, Democratic Republic of Congo
- Université de Kinshasa, Kinshasa, Democratic Republic of Congo
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Eperon G, Balasegaram M, Potet J, Mowbray C, Valverde O, Chappuis F. Treatment options for second-stage gambiense human African trypanosomiasis. Expert Rev Anti Infect Ther 2014; 12:1407-17. [PMID: 25204360 PMCID: PMC4743611 DOI: 10.1586/14787210.2014.959496] [Citation(s) in RCA: 75] [Impact Index Per Article: 7.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/19/2023]
Abstract
Treatment of second-stage gambiense human African trypanosomiasis relied on toxic arsenic-based derivatives for over 50 years. The availability and subsequent use of eflornithine, initially in monotherapy and more recently in combination with nifurtimox (NECT), has drastically improved the prognosis of treated patients. However, NECT logistic and nursing requirements remain obstacles to its deployment and use in peripheral health structures in rural sub-Saharan Africa. Two oral compounds, fexinidazole and SCYX-7158, are currently in clinical development. The main scope of this article is to discuss the potential impact of new oral therapies to improve diagnosis-treatment algorithms and patients' access to treatment, and to contribute to reach the objectives of the recently launched gambiense human African trypanosomiasis elimination program.
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Affiliation(s)
| | | | - Julien Potet
- Geneva University Hospitals,
Geneva, Switzerland
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Kryshchyshyn A, Kaminskyy D, Grellier P, Lesyk R. Trends in research of antitrypanosomal agents among synthetic heterocycles. Eur J Med Chem 2014; 85:51-64. [DOI: 10.1016/j.ejmech.2014.07.092] [Citation(s) in RCA: 24] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/06/2014] [Revised: 07/23/2014] [Accepted: 07/24/2014] [Indexed: 12/18/2022]
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Tung NH, Suzuki M, Uto T, Morinaga O, Kwofie KD, Ammah N, Koram KA, Aboagye F, Edoh D, Yamashita T, Yamaguchi Y, Setsu T, Yamaoka S, Ohta N, Shoyama Y. Anti-Trypanosomal Activity of Diarylheptanoids Isolated from the Bark ofAlnus japonica. THE AMERICAN JOURNAL OF CHINESE MEDICINE 2014; 42:1245-60. [DOI: 10.1142/s0192415x14500785] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/18/2022]
Abstract
The crude extract of Alnus japonica bark exhibited a strong effect on the growth of Trypanosoma brucei. Subsequent chromatographic separation resulted in the isolation of two novel diarylheptanoids, known as alnuside C (2) and alnuside D (3), and three known compounds, 1-(3,4-dihydroxyphenyl)-7-(4-hydroxyphenyl)-heptan-3(R)-O-β-D-glucopyranoside (1), oregonin (4) and hirsutanone (5). The structures of the isolates were elucidated based on the use of extensive spectroscopic and chemical methods. Among the isolated diarylheptanoids, oregonin (4) (a major component of plant bark) and hirsutanone (5) exhibited potent in vitro inhibitory activity against T. brucei growth in the bloodstream with IC50values of 1.14 and 1.78 μM, respectively. We confirmed that oregonin (4) and hirsutanone (5) were not toxic to human normal skin fibroblast cells (NB1RGB) and colon cancer cells (HCT-15) at a concentration of 50 μM; however, lower levels of toxicity were observed for leukemia cells. To determine the structure activity relationships of the isolated components, we performed Conformation Search and found that the 3-oxo function of the heptane chain in the diarylheptanoid molecule is required for their trypanocidal activity.
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Affiliation(s)
- Nguyen Huu Tung
- Faculty of Pharmaceutical Sciences, Nagasaki International University, Sasebo, Nagasaki 859-3298, Japan
| | - Mitsuko Suzuki
- Noguchi Memorial Institute for Medical Research, University of Ghana, Legon LG 581, Ghana
- Section of Environmental Parasitology, Faculty of Medicine, Tokyo Medical and Dental University, Bunkyo-ku, Tokyo 113-8510, Japan
| | - Takuhiro Uto
- Faculty of Pharmaceutical Sciences, Nagasaki International University, Sasebo, Nagasaki 859-3298, Japan
| | - Osamu Morinaga
- Faculty of Pharmaceutical Sciences, Nagasaki International University, Sasebo, Nagasaki 859-3298, Japan
| | - Kofi D. Kwofie
- Noguchi Memorial Institute for Medical Research, University of Ghana, Legon LG 581, Ghana
| | - Naa Ammah
- Noguchi Memorial Institute for Medical Research, University of Ghana, Legon LG 581, Ghana
| | - Kwadwo A. Koram
- Noguchi Memorial Institute for Medical Research, University of Ghana, Legon LG 581, Ghana
| | - Frederic Aboagye
- Center for Scientific Research into Plant Medicine, Mampong-Akuapem 73, Ghana
| | - Dominic Edoh
- Center for Scientific Research into Plant Medicine, Mampong-Akuapem 73, Ghana
| | - Taizo Yamashita
- Faculty of Pharmaceutical Sciences, Nagasaki International University, Sasebo, Nagasaki 859-3298, Japan
| | - Yasuchika Yamaguchi
- Faculty of Pharmaceutical Sciences, Nagasaki International University, Sasebo, Nagasaki 859-3298, Japan
| | - Takao Setsu
- University Forest, Kyushu University, Kasuya, Fukuoka 811-2415, Japan
| | - Shoji Yamaoka
- Section of Environmental Parasitology, Faculty of Medicine, Tokyo Medical and Dental University, Bunkyo-ku, Tokyo 113-8510, Japan
| | - Nobuo Ohta
- Section of Environmental Parasitology, Faculty of Medicine, Tokyo Medical and Dental University, Bunkyo-ku, Tokyo 113-8510, Japan
| | - Yukihiro Shoyama
- Faculty of Pharmaceutical Sciences, Nagasaki International University, Sasebo, Nagasaki 859-3298, Japan
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Sekhar GN, Watson CP, Fidanboylu M, Sanderson L, Thomas SA. Delivery of antihuman African trypanosomiasis drugs across the blood-brain and blood-CSF barriers. ADVANCES IN PHARMACOLOGY (SAN DIEGO, CALIF.) 2014; 71:245-75. [PMID: 25307219 DOI: 10.1016/bs.apha.2014.06.003] [Citation(s) in RCA: 17] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/13/2022]
Abstract
Human African trypanosomiasis (HAT or sleeping sickness) is a potentially fatal disease caused by the parasite, Trypanosoma brucei sp. The parasites are transmitted by the bite of insect vectors belonging to the genus Glossina (tsetse flies) and display a life cycle strategy that is equally spread between human and insect hosts. T.b. gambiense is found in western and central Africa whereas, T.b. rhodesiense is found in eastern and southern Africa. The disease has two clinical stages: a blood stage after the bite of an infected tsetse fly, followed by a central nervous system (CNS) stage where the parasite penetrates the brain; causing death if left untreated. The blood-brain barrier (BBB) makes the CNS stage difficult to treat because it prevents 98% of all known compounds from entering the brain, including some anti-HAT drugs. Those that do enter the brain are toxic compounds in their own right and have serious side effects. There are only a few drugs available to treat HAT and those that do are stage specific. This review summarizes the incidence, diagnosis, and treatment of HAT and provides a close examination of the BBB transport of anti-HAT drugs and an overview of the latest drugs in development.
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Affiliation(s)
- Gayathri N Sekhar
- King's College London, Institute of Pharmaceutical Sciences, London, United Kingdom
| | - Christopher P Watson
- King's College London, Institute of Pharmaceutical Sciences, London, United Kingdom
| | - Mehmet Fidanboylu
- King's College London, Institute of Pharmaceutical Sciences, London, United Kingdom
| | - Lisa Sanderson
- King's College London, Institute of Pharmaceutical Sciences, London, United Kingdom
| | - Sarah A Thomas
- King's College London, Institute of Pharmaceutical Sciences, London, United Kingdom.
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Characterization of a melamino nitroheterocycle as a potential lead for the treatment of human african trypanosomiasis. Antimicrob Agents Chemother 2014; 58:5747-57. [PMID: 25022590 DOI: 10.1128/aac.01449-13] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022] Open
Abstract
This paper reports an evaluation of a melamino nitroheterocycle, a potential lead for further development as an agent against human African trypanosomiasis (HAT). Studies on its efficacy, physicochemical and biopharmaceutical properties, and potential for toxicity are described. The compound previously had been shown to possess exceptional activity against Trypanosoma brucei in in vitro assays comparable to that of melarsoprol. Here, we demonstrate that the compound also was curative in the stringent acute mouse model T. brucei rhodesiense STIB 900 when given intraperitoneally at 40 mg/kg of body weight. Nevertheless, activity was only moderate when the oral route was used, and no cure was obtained when the compound was tested in a stage 2 rodent model of infection. Genotoxic profiling revealed that the compound induces DNA damage by a mechanism apparently independent from nitroreduction and involving the introduction of base pair substitutions (Ames test), possibly caused by oxidative damage of the DNA (comet test). No significant genotoxicity was observed at the chromosome level (micronucleus assay). The lack of suitable properties for oral and central nervous system uptake and the genotoxic liabilities prevent the progression of this melamine nitroheterocycle as a drug candidate for HAT. Further modification of the compound is required to improve the pharmacokinetic properties of the molecule and to separate the trypanocidal activity from the toxic potential.
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Nasimolo J, Kiama SG, Gathumbi PK, Makanya AN, Kagira JM. Erythrina abyssinica prevents meningoencephalitis in chronic Trypanosoma brucei brucei mouse model. Metab Brain Dis 2014; 29:509-19. [PMID: 24452611 DOI: 10.1007/s11011-014-9488-5] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 09/27/2013] [Accepted: 01/13/2014] [Indexed: 10/25/2022]
Abstract
Human African trypanosomiasis is prevalent in Sub-sahara African countries that lie between 14° North and 29° south of the equator. Sixty million people are at risk of infection. Trypanosoma brucei gambesience occurs in West and Central Africa while Trypanosoma brucei rhodesience occurs in East and Southern Africa. The neurological stage of the disease is characterized by neuroinflammation. About 10% of patients treated with the recommended drug, melarsoprol develop post treatment reactive encephalopathy, which is fatal in 50% of these patients, thus melarsoprol is fatal in 5% of all treated patients. This study was aimed at establishing the potential activity of Erythrina abyssinica in reducing neuroinflammation following infection with Trypanosoma brucei brucei. Swiss white mice were divided into ten groups, two control groups and eight infected groups. Infected mice received either methanol or water extract of Erythrina abyssinica at 12.5, 25, 50 or 100 mg/kg body weight. Parasite counts were monitored in peripheral circulation from the third day post infection up to the end of the study. Brains were processed for histology, immunohistochemistry scanning and transmission electron microscopy. Following infection, trypanosomes were observed in circulation 3 days post-infection, with the parasitaemia occurring in waves. In the cerebrum, typical brain pathology of chronic trypanosomiasis was reproduced. This was exhibited as astrocytosis, perivascular cuffing and infiltration of inflammatory cells into the neuropil. However, mice treated with Erythrina abyssinica water extract exhibited significant reduction in perivascular cuffing, lymphocytic infiltration and astrocytosis in the cerebrum. The methanol extract did not have a significant difference compared to the non-treated group. This study provides evidence of anti-inflammatory properties of Erythrina abyssinica and may support its wide use as a medicinal plant by various communities in Kenya.
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Affiliation(s)
- Johnson Nasimolo
- Department of Veterinary Anatomy and Physiology, University of Nairobi, Nairobi, Kenya,
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41
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Rashad AA, Jones AJ, Avery VM, Baell J, Keller PA. Facile Synthesis and Preliminary Structure-Activity Analysis of New Sulfonamides Against Trypanosoma brucei. ACS Med Chem Lett 2014; 5:496-500. [PMID: 24900868 DOI: 10.1021/ml400487t] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/26/2013] [Accepted: 03/10/2014] [Indexed: 12/17/2022] Open
Abstract
The high throughput screening of a library of over 87,000 drug-like compounds against the African sleeping sickness parasite resulted in the discovery of hits with a wide range of molecular diversity. We report here the medicinal chemistry development of one such hit, a tetrahydroisoquinoline disulfonamide, with the synthesis and testing of 26 derivatives against the trypanosome subspecies. Activities in the 2-4 μM range were revealed with a selectivity index suitable for further development.
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Affiliation(s)
- Adel A. Rashad
- School
of Chemistry, University of Wollongong, Wollongong 2522, Australia
| | - Amy J. Jones
- Eskitis
Institute for Drug Discovery, Griffith University, Brisbane Innovation Park, Don Young
Road, Nathan 4111, Australia
| | - Vicky M. Avery
- Eskitis
Institute for Drug Discovery, Griffith University, Brisbane Innovation Park, Don Young
Road, Nathan 4111, Australia
| | - Jonathan Baell
- Medicinal
Chemistry, Monash Institute of Pharmaceutical Sciences, Monash University, 381 Royal Parade, Parkville 3052, Australia
| | - Paul A. Keller
- School
of Chemistry, University of Wollongong, Wollongong 2522, Australia
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Patterson S, Wyllie S. Nitro drugs for the treatment of trypanosomatid diseases: past, present, and future prospects. Trends Parasitol 2014; 30:289-98. [PMID: 24776300 PMCID: PMC4045206 DOI: 10.1016/j.pt.2014.04.003] [Citation(s) in RCA: 218] [Impact Index Per Article: 21.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/11/2014] [Revised: 04/01/2014] [Accepted: 04/02/2014] [Indexed: 02/07/2023]
Abstract
Two nitro drugs are currently used in the treatment of trypanosomatid diseases. Several new nitroaromatics are being developed against the trypanosomatid diseases. Many nitro drugs and drug candidates act as prodrugs which require bioactivation. Nitroaromatics can have disparate mechanisms of action in trypanosomatid parasites.
There is an urgent need for new, safer, and effective treatments for the diseases caused by the protozoan parasites Trypanosoma brucei, Trypanosoma cruzi, and Leishmania spp. In the search for more effective drugs to treat these ‘neglected diseases’ researchers have chosen to reassess the therapeutic value of nitroaromatic compounds. Previously avoided in drug discovery programs owing to potential toxicity issues, a nitro drug is now being used successfully as part of a combination therapy for human African trypanosomiasis. We describe here the rehabilitation of nitro drugs for the treatment of trypanosomatid diseases and discuss the future prospects for this compound class.
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Affiliation(s)
- Stephen Patterson
- Division of Biological Chemistry and Drug Discovery, Sir James Black Centre, College of Life Sciences, University of Dundee, Dundee, UK.
| | - Susan Wyllie
- Division of Biological Chemistry and Drug Discovery, Wellcome Trust Biocentre, College of Life Sciences, University of Dundee, Dundee, UK.
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Andrews KT, Fisher G, Skinner-Adams TS. Drug repurposing and human parasitic protozoan diseases. INTERNATIONAL JOURNAL FOR PARASITOLOGY-DRUGS AND DRUG RESISTANCE 2014; 4:95-111. [PMID: 25057459 PMCID: PMC4095053 DOI: 10.1016/j.ijpddr.2014.02.002] [Citation(s) in RCA: 223] [Impact Index Per Article: 22.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 12/09/2013] [Revised: 02/17/2014] [Accepted: 02/27/2014] [Indexed: 12/30/2022]
Abstract
Parasitic diseases have an enormous health, social and economic impact and are a particular problem in tropical regions of the world. Diseases caused by protozoa and helminths, such as malaria and schistosomiasis, are the cause of most parasite related morbidity and mortality, with an estimated 1.1 million combined deaths annually. The global burden of these diseases is exacerbated by the lack of licensed vaccines, making safe and effective drugs vital to their prevention and treatment. Unfortunately, where drugs are available, their usefulness is being increasingly threatened by parasite drug resistance. The need for new drugs drives antiparasitic drug discovery research globally and requires a range of innovative strategies to ensure a sustainable pipeline of lead compounds. In this review we discuss one of these approaches, drug repurposing or repositioning, with a focus on major human parasitic protozoan diseases such as malaria, trypanosomiasis, toxoplasmosis, cryptosporidiosis and leishmaniasis.
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Affiliation(s)
- Katherine T Andrews
- Eskitis Institute for Drug Discovery, Griffith University, Nathan, Queensland, Australia
| | - Gillian Fisher
- Eskitis Institute for Drug Discovery, Griffith University, Nathan, Queensland, Australia
| | - Tina S Skinner-Adams
- Eskitis Institute for Drug Discovery, Griffith University, Nathan, Queensland, Australia
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Paul M, Stefaniak J, Smuszkiewicz P, Van Esbroeck M, Geysen D, Clerinx J. Outcome of acute East African trypanosomiasis in a Polish traveller treated with pentamidine. BMC Infect Dis 2014; 14:111. [PMID: 24571399 PMCID: PMC3941560 DOI: 10.1186/1471-2334-14-111] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/21/2013] [Accepted: 02/14/2014] [Indexed: 11/10/2022] Open
Abstract
Background African trypanosomiasis is a parasitic infection sporadically imported to Europe by tourists or immigrants returning from endemic areas. We present the first and an unusual case of East African trypanosomiasis imported to Poland by a patient returning from a tourist trip to Uganda and Rwanda, which was successfully treated with pentamidine. Case presentation A 61-year-old Polish man was admitted to the Department because of high-grade fever and multi-organ dysfunction after a tourist trip to East Africa. He experienced a single tsetse fly bite during a safari trip to the Queen Elizabeth National Park in Uganda. On admission, his clinical status was severe, with high fever of 41ºC, preceded by chills, bleeding from the gums and oral mucosa, haemorrhages at the sites of venipuncture, numerous ecchymoses, fine-spotted skin rash, tachycardia, hepatosplenomegaly, dehydration, jaundice, dyspnoea, hypoxaemia, generalised oedema and oliguria. There was a typical non-painful trypanosomal chancre with central necrosis and peripheral erythema on his left arm. Laboratory investigations showed leucopenia, thrombocytopenia, haemolytic anaemia, hyperbilirubinaemia, hypoglycaemia, elevated creatinine and urea, high activity of aminotransferases, elevated levels of inflammatory markers, hypoproteinaemia, proteinuria, abnormal clotting and bleeding times, low fibrinogen level, metabolic acidosis, and electrolyte disturbances. A peripheral blood smear showed numerous Trypanosoma brucei trypomastigotes with a massive parasitaemia of 100,000/μl. T. brucei rhodesiense subspecies was finally identified on the basis of the characteristic serum resistance-associated gene using a polymerase chain reaction, and a seroconversion of specific immunoglobulin M and G antibodies in the peripheral blood by enzyme-linked immunosorbent assay. Serological tests for T. brucei gambiense subspecies were negative. A severe clinical course of acute rhodesiense trypanosomiasis with renal failure, respiratory distress, disseminated intravascular coagulation syndrome, haemolysis, liver insufficiency and myocarditis was confirmed. Intensive anti-parasitic and symptomatic treatment was immediately instituted, including intravenous pentamidine, plasmaphereses, oxygen therapy, blood transfusion, catecholamine administration, and fluid infusions, as well as haemostatic, hepatoprotective, anti-inflammatory, antipyretic and diuretic drugs. The final outcome was a full recovery with no late sequelae. Conclusion Sleeping sickness should always be considered in the differential diagnosis of fever in people returning from safari trips to the national parks or nature reserves of sub-Saharan Africa.
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Affiliation(s)
- Małgorzata Paul
- Department and Clinic of Tropical and Parasitic Diseases, University of Medical Sciences, Przybyszewskiego 49, Poznań, Poland.
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Kenyan purple tea anthocyanins and coenzyme-Q10 ameliorate post treatment reactive encephalopathy associated with cerebral human African trypanosomiasis in murine model. Parasitol Int 2014; 63:417-26. [PMID: 24440762 DOI: 10.1016/j.parint.2014.01.001] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/13/2013] [Revised: 12/20/2013] [Accepted: 01/06/2014] [Indexed: 02/08/2023]
Abstract
Human African trypanosomiasis (HAT) is a tropical disease caused by two subspecies of Trypanosoma brucei, the East African variant T. b. rhodesiense and the West African variant T. b. gambiense. Melarsoprol, an organic arsenical, is the only drug used to treat late stage T. b. rhodesiense infection. Unfortunately, this drug induces an extremely severe post treatment reactive encephalopathy (PTRE) in up to 10% of treated patients, half of whom die from this complication. A highly reproducible mouse model was adapted to assess the use of Kenyan purple tea anthocyanins and/or coenzyme-Q10 in blocking the occurrence of PTRE. Female Swiss white mice were inoculated intraperitoneally with approximately 10(4) trypanosome isolate T. b. rhodesiense KETRI 2537 and treated sub-curatively 21days post infection with 5mg/kg diminazene aceturate (DA) daily for 3days to induce severe late CNS infection that closely mirrors PTRE in human subjects. Thereafter mice were monitored for relapse of parasitemia after which they were treated with melarsoprol at a dosage of 3.6mg/kg body weight for 4days and sacrificed 24h post the last dosage to obtain brain samples. Brain sections from mice with PTRE that did not receive any antioxidant treatment showed a more marked presence of inflammatory cells, microglial activation and disruption of the brain parenchyma when compared to PTRE mice supplemented with either coenzyme-Q10, purple tea anthocyanins or a combination of the two. The mice group that was treated with coenzyme-Q10 or purple tea anthocyanins had higher levels of GSH and aconitase-1 in the brain compared to untreated groups, implying a boost in brain antioxidant capacity. Overall, coenzyme-Q10 treatment produced more beneficial effects compared to anthocyanin treatment. These findings demonstrate that therapeutic intervention with coenzyme-Q10 and/or purple tea anthocyanins can be used in an experimental mouse model to ameliorate PTRE associated with cerebral HAT.
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Canning P, Rea D, Morty RE, Fülöp V. Crystal structures of Trypanosoma brucei oligopeptidase B broaden the paradigm of catalytic regulation in prolyl oligopeptidase family enzymes. PLoS One 2013; 8:e79349. [PMID: 24265767 PMCID: PMC3827171 DOI: 10.1371/journal.pone.0079349] [Citation(s) in RCA: 27] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/17/2013] [Accepted: 09/27/2013] [Indexed: 11/18/2022] Open
Abstract
Oligopeptidase B cleaves after basic amino acids in peptides up to 30 residues. As a virulence factor in bacteria and trypanosomatid pathogens that is absent in higher eukaryotes, this is a promising drug target. Here we present ligand-free open state and inhibitor-bound closed state crystal structures of oligopeptidase B from Trypanosoma brucei, the causative agent of African sleeping sickness. These (and related) structures show the importance of structural dynamics, governed by a fine enthalpic and entropic balance, in substrate size selectivity and catalysis. Peptides over 30 residues cannot fit the enzyme cavity, preventing the complete domain closure required for a key propeller Asp/Glu to fix the catalytic His and Arg in the catalytically competent conformation. This size exclusion mechanism protects larger peptides and proteins from degradation. Similar bacterial prolyl endopeptidase and archael acylaminoacyl peptidase structures demonstrate this mechanism is conserved among oligopeptidase family enzymes across all three domains of life.
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Affiliation(s)
- Peter Canning
- School of Life Sciences, University of Warwick, Coventry, United Kingdom
| | - Dean Rea
- School of Life Sciences, University of Warwick, Coventry, United Kingdom
| | - Rory E. Morty
- Department of Lung Development and Remodelling, Max Planck Institute for Heart and Lung Research, Bad Nauheim, Germany
| | - Vilmos Fülöp
- School of Life Sciences, University of Warwick, Coventry, United Kingdom
- * E-mail:
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Jones AJ, Grkovic T, Sykes ML, Avery VM. Trypanocidal activity of marine natural products. Mar Drugs 2013; 11:4058-82. [PMID: 24152565 PMCID: PMC3826150 DOI: 10.3390/md11104058] [Citation(s) in RCA: 30] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/16/2013] [Revised: 10/09/2013] [Accepted: 10/10/2013] [Indexed: 12/21/2022] Open
Abstract
Marine natural products are a diverse, unique collection of compounds with immense therapeutic potential. This has resulted in these molecules being evaluated for a number of different disease indications including the neglected protozoan diseases, human African trypanosomiasis and Chagas disease, for which very few drugs are currently available. This article will review the marine natural products for which activity against the kinetoplastid parasites; Trypanosoma brucei brucei, T.b. rhodesiense and T. cruzi has been reported. As it is important to know the selectivity of a compound when evaluating its trypanocidal activity, this article will only cover molecules which have simultaneously been tested for cytotoxicity against a mammalian cell line. Compounds have been grouped according to their chemical structure and representative examples from each class were selected for detailed discussion.
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Affiliation(s)
- Amy J Jones
- Eskitis Institute for Drug Discovery, Griffith University, Nathan, Brisbane 4111, Australia.
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Myburgh E, Coles JA, Ritchie R, Kennedy PGE, McLatchie AP, Rodgers J, Taylor MC, Barrett MP, Brewer JM, Mottram JC. In vivo imaging of trypanosome-brain interactions and development of a rapid screening test for drugs against CNS stage trypanosomiasis. PLoS Negl Trop Dis 2013; 7:e2384. [PMID: 23991236 PMCID: PMC3749981 DOI: 10.1371/journal.pntd.0002384] [Citation(s) in RCA: 53] [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: 01/18/2013] [Accepted: 07/13/2013] [Indexed: 11/18/2022] Open
Abstract
HUMAN AFRICAN TRYPANOSOMIASIS (HAT) MANIFESTS IN TWO STAGES OF DISEASE: firstly, haemolymphatic, and secondly, an encephalitic phase involving the central nervous system (CNS). New drugs to treat the second-stage disease are urgently needed, yet testing of novel drug candidates is a slow process because the established animal model relies on detecting parasitemia in the blood as late as 180 days after treatment. To expedite compound screening, we have modified the GVR35 strain of Trypanosoma brucei brucei to express luciferase, and have monitored parasite distribution in infected mice following treatment with trypanocidal compounds using serial, non-invasive, bioluminescence imaging. Parasites were detected in the brains of infected mice following treatment with diminazene, a drug which cures stage 1 but not stage 2 disease. Intravital multi-photon microscopy revealed that trypanosomes enter the brain meninges as early as day 5 post-infection but can be killed by diminazene, whereas those that cross the blood-brain barrier and enter the parenchyma by day 21 survived treatment and later caused bloodstream recrudescence. In contrast, all bioluminescent parasites were permanently eliminated by treatment with melarsoprol and DB829, compounds known to cure stage 2 disease. We show that this use of imaging reduces by two thirds the time taken to assess drug efficacy and provides a dual-modal imaging platform for monitoring trypanosome infection in different areas of the brain.
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Affiliation(s)
- Elmarie Myburgh
- Wellcome Trust Centre for Molecular Parasitology, College of Medical, Veterinary and Life Sciences, University of Glasgow, Glasgow, United Kingdom
- Institute of Infection, Immunity and Inflammation, College of Medical, Veterinary and Life Sciences, University of Glasgow, Glasgow, United Kingdom
| | - Jonathan A. Coles
- Wellcome Trust Centre for Molecular Parasitology, College of Medical, Veterinary and Life Sciences, University of Glasgow, Glasgow, United Kingdom
- Institute of Infection, Immunity and Inflammation, College of Medical, Veterinary and Life Sciences, University of Glasgow, Glasgow, United Kingdom
| | - Ryan Ritchie
- Wellcome Trust Centre for Molecular Parasitology, College of Medical, Veterinary and Life Sciences, University of Glasgow, Glasgow, United Kingdom
- Institute of Infection, Immunity and Inflammation, College of Medical, Veterinary and Life Sciences, University of Glasgow, Glasgow, United Kingdom
| | - Peter G. E. Kennedy
- Institute of Infection, Immunity and Inflammation, College of Medical, Veterinary and Life Sciences, University of Glasgow, Glasgow, United Kingdom
| | - Alex P. McLatchie
- Faculty of Infectious and Tropical Diseases, London School of Hygiene and Tropical Medicine, London, United Kingdom
| | - Jean Rodgers
- Institute of Infection, Immunity and Inflammation, College of Medical, Veterinary and Life Sciences, University of Glasgow, Glasgow, United Kingdom
| | - Martin C. Taylor
- Faculty of Infectious and Tropical Diseases, London School of Hygiene and Tropical Medicine, London, United Kingdom
| | - Michael P. Barrett
- Wellcome Trust Centre for Molecular Parasitology, College of Medical, Veterinary and Life Sciences, University of Glasgow, Glasgow, United Kingdom
- Institute of Infection, Immunity and Inflammation, College of Medical, Veterinary and Life Sciences, University of Glasgow, Glasgow, United Kingdom
- * E-mail:
| | - James M. Brewer
- Wellcome Trust Centre for Molecular Parasitology, College of Medical, Veterinary and Life Sciences, University of Glasgow, Glasgow, United Kingdom
- Institute of Infection, Immunity and Inflammation, College of Medical, Veterinary and Life Sciences, University of Glasgow, Glasgow, United Kingdom
| | - Jeremy C. Mottram
- Wellcome Trust Centre for Molecular Parasitology, College of Medical, Veterinary and Life Sciences, University of Glasgow, Glasgow, United Kingdom
- Institute of Infection, Immunity and Inflammation, College of Medical, Veterinary and Life Sciences, University of Glasgow, Glasgow, United Kingdom
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Bukachi SA, Wandibba S, Nyamongo IK. The treatment pathways followed by cases of human African trypanosomiasis in western Kenya and eastern Uganda. ANNALS OF TROPICAL MEDICINE AND PARASITOLOGY 2013; 103:211-20. [DOI: 10.1179/136485909x398230] [Citation(s) in RCA: 17] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/28/2022]
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Abstract
BACKGROUND Human African trypanosomiasis, or sleeping sickness, is a painful and protracted disease affecting people in the poorest parts of Africa and is fatal without treatment. Few drugs are currently available for second-stage sleeping sickness, with considerable adverse events and variable efficacy. OBJECTIVES To evaluate the effectiveness and safety of drugs for treating second-stage human African trypanosomiasis. SEARCH METHODS We searched the Cochrane Infectious Diseases Group Specialized Register (January 2013), CENTRAL (The Cochrane Library Issue 12 2012) , MEDLINE (1966 to January 2013), EMBASE (1974 to January 2013), LILACS (1982 to January 2013 ), BIOSIS (1926-January 2013), mRCT (January 2013) and reference lists. We contacted researchers working in the field and organizations. SELECTION CRITERIA Randomized and quasi-randomized controlled trials including adults and children with second-stage HAT, treated with anti-trypanosomal drugs. DATA COLLECTION AND ANALYSIS Two authors (VL and AK) extracted data and assessed methodological quality; a third author (JS) acted as an arbitrator. Included trials only reported dichotomous outcomes, and we present these as risk ratio (RR) with 95% confidence intervals (CI). MAIN RESULTS Nine trials with 2577 participants, all with Trypansoma brucei gambiense HAT, were included. Seven trials tested currently available drugs: melarsoprol, eflornithine, nifurtimox, alone or in combination; one trial tested pentamidine, and one trial assessed the addition of prednisolone to melarsoprol. The frequency of death and number of adverse events were similar between patients treated with fixed 10-day regimens of melarsoprol or 26-days regimens. Melarsoprol monotherapy gave fewer relapses than pentamidine or nifurtimox, but resulted in more adverse events.Later trials evaluate nifurtimox combined with eflornithine (NECT), showing this gives few relapses and is well tolerated. It also has practical advantages in reducing the frequency and number of eflornithine slow infusions to twice a day, thus easing the burden on health personnel and patients. AUTHORS' CONCLUSIONS Choice of therapy for second stage Gambiense HAT will continue to be determined by what is locally available, but eflornithine and NECT are likely to replace melarsoprol, with careful parasite resistance monitoring. We need research on reducing adverse effects of currently used drugs, testing different regimens, and experimental and clinical studies of new compounds, effective for both stages of the disease.
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Affiliation(s)
- Vittoria Lutje
- Department of Clinical Sciences, Liverpool School of Tropical Medicine, Liverpool, UK.
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