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Ribeiro R, Costa L, Pinto E, Sousa E, Fernandes C. Therapeutic Potential of Marine-Derived Cyclic Peptides as Antiparasitic Agents. Mar Drugs 2023; 21:609. [PMID: 38132930 PMCID: PMC10745025 DOI: 10.3390/md21120609] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/02/2023] [Revised: 11/18/2023] [Accepted: 11/23/2023] [Indexed: 12/23/2023] Open
Abstract
Parasitic diseases still compromise human health. Some of the currently available therapeutic drugs have limitations considering their adverse effects, questionable efficacy, and long treatment, which have encouraged drug resistance. There is an urgent need to find new, safe, effective, and affordable antiparasitic drugs. Marine-derived cyclic peptides have been increasingly screened as candidates for developing new drugs. Therefore, in this review, a systematic analysis of the scientific literature was performed and 25 marine-derived cyclic peptides with antiparasitic activity (1-25) were found. Antimalarial activity is the most reported (51%), followed by antileishmanial (27%) and antitrypanosomal (20%) activities. Some compounds showed promising antiparasitic activity at the nM scale, being active against various parasites. The mechanisms of action and targets for some of the compounds have been investigated, revealing different strategies against parasites.
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Affiliation(s)
- Ricardo Ribeiro
- Laboratório de Química Orgânica e Farmacêutica, Departamento de Ciências Químicas, Faculdade de Farmácia, Universidade do Porto, Rua de Jorge Viterbo Ferreira, 228, 4050-313 Porto, Portugal; (R.R.); (L.C.); (E.S.)
- Interdisciplinary Centre of Marine and Environmental Research (CIIMAR), Edifício do Terminal de Cruzeiros do Porto de Leixões, Av. General Norton de Matos s/n, 4050-208 Matosinhos, Portugal;
| | - Lia Costa
- Laboratório de Química Orgânica e Farmacêutica, Departamento de Ciências Químicas, Faculdade de Farmácia, Universidade do Porto, Rua de Jorge Viterbo Ferreira, 228, 4050-313 Porto, Portugal; (R.R.); (L.C.); (E.S.)
| | - Eugénia Pinto
- Interdisciplinary Centre of Marine and Environmental Research (CIIMAR), Edifício do Terminal de Cruzeiros do Porto de Leixões, Av. General Norton de Matos s/n, 4050-208 Matosinhos, Portugal;
- Laboratório de Microbiologia, Departamento de Ciências Biológicas, Faculdade de Farmácia, Universidade do Porto, Rua de Jorge Viterbo Ferreira 228, 4050-313 Porto, Portugal
| | - Emília Sousa
- Laboratório de Química Orgânica e Farmacêutica, Departamento de Ciências Químicas, Faculdade de Farmácia, Universidade do Porto, Rua de Jorge Viterbo Ferreira, 228, 4050-313 Porto, Portugal; (R.R.); (L.C.); (E.S.)
- Interdisciplinary Centre of Marine and Environmental Research (CIIMAR), Edifício do Terminal de Cruzeiros do Porto de Leixões, Av. General Norton de Matos s/n, 4050-208 Matosinhos, Portugal;
| | - Carla Fernandes
- Laboratório de Química Orgânica e Farmacêutica, Departamento de Ciências Químicas, Faculdade de Farmácia, Universidade do Porto, Rua de Jorge Viterbo Ferreira, 228, 4050-313 Porto, Portugal; (R.R.); (L.C.); (E.S.)
- Interdisciplinary Centre of Marine and Environmental Research (CIIMAR), Edifício do Terminal de Cruzeiros do Porto de Leixões, Av. General Norton de Matos s/n, 4050-208 Matosinhos, Portugal;
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Wang QQ, He K, Aleem MT, Long S. Prenyl Transferases Regulate Secretory Protein Sorting and Parasite Morphology in Toxoplasma gondii. Int J Mol Sci 2023; 24:ijms24087172. [PMID: 37108334 PMCID: PMC10138696 DOI: 10.3390/ijms24087172] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/11/2023] [Revised: 04/01/2023] [Accepted: 04/07/2023] [Indexed: 04/29/2023] Open
Abstract
Protein prenylation is an important protein modification that is responsible for diverse physiological activities in eukaryotic cells. This modification is generally catalyzed by three types of prenyl transferases, which include farnesyl transferase (FT), geranylgeranyl transferase (GGT-1) and Rab geranylgeranyl transferase (GGT-2). Studies in malaria parasites showed that these parasites contain prenylated proteins, which are proposed to play multiple functions in parasites. However, the prenyl transferases have not been functionally characterized in parasites of subphylum Apicomplexa. Here, we functionally dissected functions of three of the prenyl transferases in the Apicomplexa model organism Toxoplasma gondii (T. gondii) using a plant auxin-inducible degron system. The homologous genes of the beta subunit of FT, GGT-1 and GGT-2 were endogenously tagged with AID at the C-terminus in the TIR1 parental line using a CRISPR-Cas9 approach. Upon depletion of these prenyl transferases, GGT-1 and GGT-2 had a strong defect on parasite replication. Fluorescent assay using diverse protein markers showed that the protein markers ROP5 and GRA7 were diffused in the parasites depleted with GGT-1 and GGT-2, while the mitochondrion was strongly affected in parasites depleted with GGT-1. Importantly, depletion of GGT-2 caused the stronger defect to the sorting of rhoptry protein and the parasite morphology. Furthermore, parasite motility was observed to be affected in parasites depleted with GGT-2. Taken together, this study functionally characterized the prenyl transferases, which contributed to an overall understanding of protein prenylation in T. gondii and potentially in other related parasites.
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Affiliation(s)
- Qiang-Qiang Wang
- National Key Laboratory of Veterinary Public Health Security, School of Veterinary Medicine, China Agricultural University, Beijing 100193, China
| | - Kai He
- National Key Laboratory of Veterinary Public Health Security, School of Veterinary Medicine, China Agricultural University, Beijing 100193, China
| | - Muhammad-Tahir Aleem
- Center for Gene Regulation in Health and Disease, Department of Biological, Geological and Environmental Sciences, College of Sciences and Health Professions, Cleveland State University, Cleveland, OH 44115, USA
| | - Shaojun Long
- National Key Laboratory of Veterinary Public Health Security, School of Veterinary Medicine, China Agricultural University, Beijing 100193, China
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Abstract
Purpose of Review Review building of programs to eliminate Toxoplasma infections. Recent Findings
Morbidity and mortality from toxoplasmosis led to programs in USA, Panama, and Colombia to facilitate understanding, treatment, prevention, and regional resources, incorporating student work. Summary Studies foundational for building recent, regional approaches/programs are reviewed. Introduction provides an overview/review of programs in Panamá, the United States, and other countries. High prevalence/risk of exposure led to laws mandating testing in gestation, reporting, and development of broad-based teaching materials about Toxoplasma. These were tested for efficacy as learning tools for high-school students, pregnant women, medical students, physicians, scientists, public health officials and general public. Digitized, free, smart phone application effectively taught pregnant women about toxoplasmosis prevention. Perinatal infection care programs, identifying true regional risk factors, and point-of-care gestational screening facilitate prevention and care. When implemented fully across all demographics, such programs present opportunities to save lives, sight, and cognition with considerable spillover benefits for individuals and societies. Supplementary Information The online version contains supplementary material available at 10.1007/s40124-022-00269-w.
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Building Programs to Eradicate Toxoplasmosis Part IV: Understanding and Development of Public Health Strategies and Advances “Take a Village”. CURRENT PEDIATRICS REPORTS 2022; 10:125-154. [PMID: 35991908 PMCID: PMC9379243 DOI: 10.1007/s40124-022-00268-x] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Accepted: 04/29/2022] [Indexed: 11/12/2022]
Abstract
Purpose of Review Review international efforts to build a global public health initiative focused on toxoplasmosis with spillover benefits to save lives, sight, cognition and motor function benefiting maternal and child health. Recent Findings Multiple countries’ efforts to eliminate toxoplasmosis demonstrate progress and context for this review and new work. Summary Problems with potential solutions proposed include accessibility of accurate, inexpensive diagnostic testing, pre-natal screening and facilitating tools, missed and delayed neonatal diagnosis, restricted access, high costs, delays in obtaining medicines emergently, delayed insurance pre-approvals and high medicare copays taking considerable physician time and effort, harmful shortcuts being taken in methods to prepare medicines in settings where access is restricted, reluctance to perform ventriculoperitoneal shunts promptly when needed without recognition of potential benefit, access to resources for care, especially for marginalized populations, and limited use of recent advances in management of neurologic and retinal disease which can lead to good outcomes. Supplementary Information The online version contains supplementary material available at 10.1007/s40124-022-00268-x.
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Wu L, Yang H, Wang J, Yu X, He Y, Chen S. A Novel Combined DNA Vaccine Encoding Toxoplasma gondii SAG1 and ROP18 Provokes Protective Immunity Against a Lethal Challenge in Mice. Acta Parasitol 2021; 66:1387-1395. [PMID: 34019277 DOI: 10.1007/s11686-021-00415-2] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/28/2020] [Accepted: 05/08/2021] [Indexed: 11/29/2022]
Abstract
PURPOSE Antigens expressed by Toxoplasma gondii (T. gondii) during its life cycle trigger various immune responses in the host. Recently, toxoplasma vaccine research focused on T. gondii surface antigen 1 (SAG1) and Rhoptry Protein 18 (ROP18) to establish a safe and efficacious DNA vaccine. METHOD We constructed two eukaryotic expression plasmids: p3 × FLAG-Myc-CMV™-24-SAG1 and p3 × FLAG-Myc-CMV™-24-ROP18. BALB/c mice were randomly divided into six groups and immunized with these DNA vaccines either separately or in combination. The combination vaccine was administered at either the full dose or at half-strength dose. Control mice were immunized with empty vector or with phosphate-buffered saline. RESULTS The frequency of CD4+ cells in the spleen was consistent among all groups, whereas that of CD8+ T cells was the highest in the group immunized with the combination vaccine at half-strength dose (p < 0.05). Importantly, the mRNA expression levels of interleukin-12 (IL-12) and interferon-gamma (INF-γ) were closely correlated (r = 0.6, p < 0.0001) and both were upregulated in the group that was immunized with the combination vaccine at half-strength dose (p < 0.0001). The survival time of the mice subjected to a lethal dose of toxoplasma was significantly extended by prior immunization with DNA vaccines expressing either SAG1 or ROP18 or a combination of both (p < 0.05). The group that was immunized with the combination vaccine at half-strength dose demonstrated the best efficacy (p < 0.05). CONCLUSION These results showed that the combination DNA vaccine provided better immune protection than the single gene vaccines, and that optimizing the dosing of the vaccine can improve the immune response.
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Affiliation(s)
- Lamei Wu
- Department of Clinical Laboratory, Anting Hospital, Jiading District, Shanghai, 201800, China
| | - Huijian Yang
- Department of Laboratory Medicine, Shanghai East Hospital, Tongji University School of Medicine, Shanghai, 200120, China
| | - Jianglin Wang
- Department of Clinical Laboratory, Jiading District Central Hospital Affiliated Shanghai University of Medicine and Health Sciences, Jiading District, Shanghai, 201800, China
| | - Xiuwen Yu
- Department of Clinical Laboratory, Jiading District Central Hospital Affiliated Shanghai University of Medicine and Health Sciences, Jiading District, Shanghai, 201800, China
| | - Yanhong He
- Department of Clinical Laboratory, Anting Hospital, Jiading District, Shanghai, 201800, China.
| | - Shenxia Chen
- Department of Microbiology, Medical College of Jiangsu University, ZhenJiang, 212013, China.
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Borkens Y. [Toxoplasma gondii-Current drugs and future vaccines against an underestimated protozoan infection]. Internist (Berl) 2021; 62:1123-1132. [PMID: 34467425 DOI: 10.1007/s00108-021-01155-1] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 08/23/2021] [Indexed: 12/01/2022]
Abstract
Toxoplasma gondii is a unicellular organism of the Apicomplexa that occurs worldwide and is therefore a close relative of the malaria pathogen Plasmodium. As T. gondii infests every warm-blooded vertebrate species as an intermediate host and has a very high prevalence worldwide, toxoplasmosis is one of the most important international foodborne diseases. Potential vaccines (human as well as veterinary) play a crucial role in controlling this disease.
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Affiliation(s)
- Yannick Borkens
- College of Public Health, Medical and Veterinary Science, James Cook University, 1 James Cook Drive, 4811, Townsville, Queensland, Australien.
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Smith NC, Goulart C, Hayward JA, Kupz A, Miller CM, van Dooren GG. Control of human toxoplasmosis. Int J Parasitol 2020; 51:95-121. [PMID: 33347832 DOI: 10.1016/j.ijpara.2020.11.001] [Citation(s) in RCA: 69] [Impact Index Per Article: 17.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/16/2020] [Revised: 11/12/2020] [Accepted: 11/15/2020] [Indexed: 12/21/2022]
Abstract
Toxoplasmosis is caused by Toxoplasma gondii, an apicomplexan parasite that is able to infect any nucleated cell in any warm-blooded animal. Toxoplasma gondii infects around 2 billion people and, whilst only a small percentage of infected people will suffer serious disease, the prevalence of the parasite makes it one of the most damaging zoonotic diseases in the world. Toxoplasmosis is a disease with multiple manifestations: it can cause a fatal encephalitis in immunosuppressed people; if first contracted during pregnancy, it can cause miscarriage or congenital defects in the neonate; and it can cause serious ocular disease, even in immunocompetent people. The disease has a complex epidemiology, being transmitted by ingestion of oocysts that are shed in the faeces of definitive feline hosts and contaminate water, soil and crops, or by consumption of intracellular cysts in undercooked meat from intermediate hosts. In this review we examine current and future approaches to control toxoplasmosis, which encompass a variety of measures that target different components of the life cycle of T. gondii. These include: education programs about the parasite and avoidance of contact with infectious stages; biosecurity and sanitation to ensure food and water safety; chemo- and immunotherapeutics to control active infections and disease; prophylactic options to prevent acquisition of infection by livestock and cyst formation in meat; and vaccines to prevent shedding of oocysts by definitive feline hosts.
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Affiliation(s)
- Nicholas C Smith
- School of Life Sciences, University of Technology Sydney, Ultimo, NSW 2007, Australia; Research School of Biology, Australian National University, Canberra, ACT 0200, Australia.
| | - Cibelly Goulart
- School of Life Sciences, University of Technology Sydney, Ultimo, NSW 2007, Australia; Research School of Biology, Australian National University, Canberra, ACT 0200, Australia
| | - Jenni A Hayward
- Research School of Biology, Australian National University, Canberra, ACT 0200, Australia
| | - Andreas Kupz
- Centre for Molecular Therapeutics, Australian Institute of Tropical Health and Medicine, James Cook University, Cairns, QLD 4878, Australia
| | - Catherine M Miller
- College of Public Health, Medical and Veterinary Science, James Cook University, Cairns, QLD 4878, Australia
| | - Giel G van Dooren
- Research School of Biology, Australian National University, Canberra, ACT 0200, Australia
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Remcho TP, Guggilapu SD, Cruz P, Nardone GA, Heffernan G, O'Connor RD, Bewley CA, Wellems TE, Lane KD. Regioisomerization of Antimalarial Drug WR99210 Explains the Inactivity of a Commercial Stock. Antimicrob Agents Chemother 2020; 65:e01385-20. [PMID: 33077647 PMCID: PMC7927815 DOI: 10.1128/aac.01385-20] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/02/2020] [Accepted: 10/09/2020] [Indexed: 11/20/2022] Open
Abstract
WR99210, a former antimalarial drug candidate now widely used for the selection of Plasmodium transfectants, selectively targets the parasite's dihydrofolate reductase thymidine synthase bifunctional enzyme (DHFR-TS) but not human DHFR, which is not fused with TS. Accordingly, WR99210 and plasmids expressing the human dhfr gene have become valued tools for the genetic modification of parasites in the laboratory. Concerns over the ineffectiveness of WR99210 from some sources encouraged us to investigate the biological and chemical differences of supplies from two different companies (compounds 1 and 2). Compound 1 proved effective at low nanomolar concentrations against Plasmodium falciparum parasites, whereas compound 2 was ineffective, even at micromolar concentrations. Intact and fragmented mass spectra indicated identical molecular formulae of the unprotonated (free base) structures of compounds 1 and 2; however, the compounds displayed differences by thin-layer chromatography, reverse-phase high-performance liquid chromatography, and UV-visible spectroscopy, indicating important isomeric differences. Structural evaluations by 1H, 13C, and 15N nuclear magnetic resonance spectroscopy confirmed compound 1 as WR99210 and compound 2 as a dihydrotriazine regioisomer. Induced fit computational docking models showed that compound 1 binds tightly and specifically in the P. falciparum DHFR active site, whereas compound 2 fits poorly to the active site in loose and varied orientations. Stocks and concentrates of WR99210 should be monitored for the presence of regioisomer 2, particularly when they are not supplied as the hydrochloride salt or are exposed to basic conditions that may promote rearrangement. Absorption spectroscopy can serve for assays of the unrearranged and rearranged triazines.
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Affiliation(s)
- T Parks Remcho
- Laboratory of Malaria and Vector Research, National Institute of Allergy and Infectious Diseases, National Institutes of Health, Rockville, Maryland, USA
| | - Sravanthi D Guggilapu
- Laboratory of Bioorganic Chemistry, National Institute of Diabetes and Digestive and Kidney Diseases, National Institutes of Health, Bethesda, Maryland, USA
| | - Phillip Cruz
- Office of Cyber Infrastructure and Computational Biology, National Institute of Allergy and Infectious Diseases, National Institutes of Health, Bethesda, Maryland, USA
| | - Glenn A Nardone
- Research Technologies Branch, National Institute of Allergy and Infectious Diseases, National Institutes of Health, Rockville, Maryland, USA
| | - Gavin Heffernan
- Jacobus Pharmaceutical Company, Inc., Princeton, New Jersey, USA
| | - Robert D O'Connor
- Laboratory of Bioorganic Chemistry, National Institute of Diabetes and Digestive and Kidney Diseases, National Institutes of Health, Bethesda, Maryland, USA
| | - Carole A Bewley
- Laboratory of Bioorganic Chemistry, National Institute of Diabetes and Digestive and Kidney Diseases, National Institutes of Health, Bethesda, Maryland, USA
| | - Thomas E Wellems
- Laboratory of Malaria and Vector Research, National Institute of Allergy and Infectious Diseases, National Institutes of Health, Rockville, Maryland, USA
| | - Kristin D Lane
- Laboratory of Malaria and Vector Research, National Institute of Allergy and Infectious Diseases, National Institutes of Health, Rockville, Maryland, USA
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Sander VA, Sánchez López EF, Mendoza Morales L, Ramos Duarte VA, Corigliano MG, Clemente M. Use of Veterinary Vaccines for Livestock as a Strategy to Control Foodborne Parasitic Diseases. Front Cell Infect Microbiol 2020; 10:288. [PMID: 32670892 PMCID: PMC7332557 DOI: 10.3389/fcimb.2020.00288] [Citation(s) in RCA: 24] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/21/2020] [Accepted: 05/14/2020] [Indexed: 12/19/2022] Open
Abstract
Foodborne diseases (FBDs) are a major concern worldwide since they are associated with high mortality and morbidity in the human population. Among the causative agents of FBDs, Taenia solium, Echinococcus granulosus, Toxoplasma gondii, Cryptosporidium spp., and Trichinella spiralis are listed in the top global risk ranking of foodborne parasites. One common feature between them is that they affect domestic livestock, encompassing an enormous risk to global food production and human health from farm to fork, infecting animals, and people either directly or indirectly. Several approaches have been employed to control FBDs caused by parasites, including veterinary vaccines for livestock. Veterinary vaccines against foodborne parasites not only improve the animal health by controlling animal infections but also contribute to increase public health by controlling an important source of FBDs. In the present review, we discuss the advances in the development of veterinary vaccines for domestic livestock as a strategy to control foodborne parasitic diseases.
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Affiliation(s)
| | | | | | | | | | - Marina Clemente
- Laboratorio de Molecular Farming y Vacunas, Unidad Biotecnológica 6-UB6, INTECH, UNSAM-CONICET, Chascomús, Argentina
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Abugri DA, Jaynes JM, Witola WH. Anti-Toxoplasma activity of Sorghum bicolor-derived lipophilic fractions. BMC Res Notes 2019; 12:688. [PMID: 31651353 PMCID: PMC6814109 DOI: 10.1186/s13104-019-4732-z] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/15/2019] [Accepted: 10/14/2019] [Indexed: 11/10/2022] Open
Abstract
Objective Toxoplasma gondii, an intracellular zoonotic parasite, infects approximately a third of the world population. Current drugs for treatment of T. gondii infection have been challenged with ineffectiveness and adverse side effects. This necessitates development of new anti-Toxoplasma drugs. Sorghum bicolor [Moench] leaf extract has been used in African traditional medicine for the management of anemia and treatment of infectious diseases. We tested the in vitro anti-Toxoplasma inhibitory activity of S. bicolor’s oil-like crude extracts and fractions against T. gondii and determined their cytotoxic effects on human host cells. Results Significant inhibitory activities against the growth of T. gondii tachyzoites were observed for the crude extract (IC50 = 3.65 µg/mL), the hexane-methanol fraction (IC50 = 2.74 µg/mL), and the hexane fraction (IC50 = 3.55 µg/mL) after 48 h of culture. The minimum cytotoxicity concentrations against HFF were 34.41, 16.92 and 7.23 µg/mL for crude extract, hexane-methanol and hexane fractions, respectively. The crude extract and fractions showed high antiparasitic effects with low cytotoxic effects. Further studies to determine synergistic activities and modes of action would provide impetus for the development of new toxoplasmosis drugs or nutraceuticals.
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Affiliation(s)
- Daniel A Abugri
- Department of Chemistry and Department of Biology, Laboratory of Ethnomedicine, Parasitology and Drug Discovery, College of Arts and Sciences, Tuskegee University, Tuskegee, AL, USA.
| | - Jesse M Jaynes
- Department of Agricultural and Environmental Sciences, College of Agriculture, Environment and Nutrition Sciences, Tuskegee University, Tuskegee, AL, 36088, USA
| | - William H Witola
- Department of Pathobiology, College of Veterinary Medicine, University of Illinois, Urbana-Champaign, IL, 61802, USA
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Lapinskas PJ, Ben-Harari RR. Perspective on current and emerging drugs in the treatment of acute and chronic toxoplasmosis. Postgrad Med 2019; 131:589-596. [PMID: 31399001 DOI: 10.1080/00325481.2019.1655258] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/15/2022]
Abstract
No new drugs for treatment of toxoplasmosis have been approved in over 60 years, despite the burden of toxoplasmosis on human society. The small selection of effective drugs is limited by important side effects, often limiting patient use. This perspective highlights promising late-stage drug candidates in the treatment of toxoplasmosis. Presently, drugs target the tachyzoite form of the parasite Toxoplasma gondii responsible for the acute infection but do not eradicate the tissue cyst form underlying chronic infection. Pyrimethamine - the first-line and only approved drug for treatment of toxoplasmosis in the United States - inhibits parasite DNA synthesis by inhibiting dihydrofolate reductase (DHFR). Two novel DHFR inhibitors with improved potency and selectivity for parasite DHFR over human DHFR are in clinical-stage development. One of the most advanced and promising therapeutic targets, demonstrating potential to treat both acute and chronic toxoplasmosis, is the calcium-dependent protein kinase 1 (CDPK1) which plays an essential role in the intracellular replicative cycle of the parasite, and has no direct mammalian homolog. Two CDPK1 inhibitor programs have identified potent and selective lead series, demonstrating acceptable systemic and CNS exposure, and in vivo efficacy in animal models of acute and chronic infection. Physicians need a better arsenal of parasiticidal drugs for the treatment of toxoplasmosis, particularly those active against tissue cysts.
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Konstantinovic N, Guegan H, Stäjner T, Belaz S, Robert-Gangneux F. Treatment of toxoplasmosis: Current options and future perspectives. Food Waterborne Parasitol 2019; 15:e00036. [PMID: 32095610 PMCID: PMC7033996 DOI: 10.1016/j.fawpar.2019.e00036] [Citation(s) in RCA: 87] [Impact Index Per Article: 17.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/12/2018] [Revised: 01/24/2019] [Accepted: 01/27/2019] [Indexed: 02/08/2023] Open
Abstract
Toxoplasmosis is a worldwide parasitic disease infecting about one third of humans, with possible severe outcomes in neonates and immunocompromised patients. Despite continuous and successful efforts to improve diagnosis, therapeutic schemes have barely evolved since many years. This article aims at reviewing the main clinical trials and current treatment practices, and at addressing future perspectives in the light of ongoing researches.
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Affiliation(s)
- Neda Konstantinovic
- National Reference Laboratory for Toxoplasmosis, Institute for Medical Research, University of Belgrade, 11129 Belgrade, Serbia
| | - Hélène Guegan
- Univ Rennes, CHU Rennes, Inserm, EHESP, Irset - UMR_S 1085, F-35000 Rennes, France
| | - Tijana Stäjner
- National Reference Laboratory for Toxoplasmosis, Institute for Medical Research, University of Belgrade, 11129 Belgrade, Serbia
| | - Sorya Belaz
- Univ Rennes, CHU Rennes, Inserm, EHESP, Irset - UMR_S 1085, F-35000 Rennes, France
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Lim SSY, Chua KH, Nölke G, Spiegel H, Goh WL, Chow SC, Kee BP, Fischer R, Schillberg S, Othman RY. Plant-derived chimeric antibodies inhibit the invasion of human fibroblasts by Toxoplasma gondii. PeerJ 2018; 6:e5780. [PMID: 30581655 PMCID: PMC6294049 DOI: 10.7717/peerj.5780] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/14/2017] [Accepted: 09/17/2018] [Indexed: 11/25/2022] Open
Abstract
The parasite Toxoplasma gondii causes an opportunistic infection, that is, particularly severe in immunocompromised patients, infants, and neonates. Current antiparasitic drugs are teratogenic and cause hypersensitivity-based toxic side effects especially during prolonged treatment. Furthermore, the recent emergence of drug-resistant toxoplasmosis has reduced the therapeutic impact of such drugs. In an effort to develop recombinant antibodies as a therapeutic alternative, a panel of affinity-matured, T. gondii tachyzoite-specific single-chain variable fragment (scFv) antibodies was selected by phage display and bioinformatic analysis. Further affinity optimization was attempted by introducing point mutations at hotspots within light chain complementarity-determining region 2. This strategy yielded four mutated scFv sequences and a parental scFv that were used to produce five mouse-human chimeric IgGs in Nicotiana benthamiana plants, with yields of 33-72 mg/kg of plant tissue. Immunological analysis confirmed the specific binding of these plant-derived antibodies to T. gondii tachyzoites, and in vitro efficacy was demonstrated by their ability to inhibit the invasion of human fibroblasts and impair parasite infectivity. These novel recombinant antibodies could therefore be suitable for the development of plant-derived immunotherapeutic interventions against toxoplasmosis.
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Affiliation(s)
| | - Kek Heng Chua
- Department of Biomedical Science, Faculty of Medicine, University of Malaya, Kuala Lumpur, Malaysia
| | - Greta Nölke
- Fraunhofer Institute for Molecular Biology and Applied Ecology IME, Aachen, Germany
| | - Holger Spiegel
- Fraunhofer Institute for Molecular Biology and Applied Ecology IME, Aachen, Germany
| | - Wai Leong Goh
- School of Science, Monash University Malaysia, Bandar Sunway, Selangor, Malaysia
| | - Sek Chuen Chow
- School of Science, Monash University Malaysia, Bandar Sunway, Selangor, Malaysia
| | - Boon Pin Kee
- Department of Biomedical Science, Faculty of Medicine, University of Malaya, Kuala Lumpur, Malaysia
| | - Rainer Fischer
- Fraunhofer Institute for Molecular Biology and Applied Ecology IME, Aachen, Germany
| | - Stefan Schillberg
- Fraunhofer Institute for Molecular Biology and Applied Ecology IME, Aachen, Germany
| | - Rofina Yasmin Othman
- Institute of Biological Sciences, University of Malaya, Kuala Lumpur, Malaysia
- Centre for Research in Biotechnology for Agriculture, University of Malaya, Kuala Lumpur, Malaysia
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Carradori S, Secci D, Bizzarri B, Chimenti P, De Monte C, Guglielmi P, Campestre C, Rivanera D, Bordón C, Jones-Brando L. Synthesis and biological evaluation of anti-Toxoplasma gondii activity of a novel scaffold of thiazolidinone derivatives. J Enzyme Inhib Med Chem 2017; 32:746-758. [PMID: 28537532 PMCID: PMC6445228 DOI: 10.1080/14756366.2017.1316494] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/02/2023] Open
Abstract
We designed and synthesised novel N-substituted 1,3-thiazolidin-4-one derivatives for the evaluation of their anti-Toxoplasma gondii efficacy. This scaffold was functionalised both at the N1-hydrazine portion with three structurally different moieties and at the lactam nitrogen with substituted benzyl groups selected on the basis of our previous structure-activity relationships studies. Using three different assay methods, the compounds were assessed in vitro to determine both the levels of efficacy against the tachyzoites of T. gondii (IC50 = 5-148 μM), as well as any evidence of cytotoxicity towards human host cells (TD50 = 68 to ≥320 μM). Results revealed that ferrocene-based thiazolidinones can possess potent anti-tachyzoite activity (TI =2-64).
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Affiliation(s)
- Simone Carradori
- a Department of Pharmacy , "G. D'Annunzio" University of Chieti-Pescara , Chieti , Italy
| | - Daniela Secci
- b Department of Drug Chemistry and Technologies , Sapienza University of Rome , Rome , Italy
| | - Bruna Bizzarri
- b Department of Drug Chemistry and Technologies , Sapienza University of Rome , Rome , Italy
| | - Paola Chimenti
- b Department of Drug Chemistry and Technologies , Sapienza University of Rome , Rome , Italy
| | - Celeste De Monte
- b Department of Drug Chemistry and Technologies , Sapienza University of Rome , Rome , Italy
| | - Paolo Guglielmi
- b Department of Drug Chemistry and Technologies , Sapienza University of Rome , Rome , Italy
| | - Cristina Campestre
- a Department of Pharmacy , "G. D'Annunzio" University of Chieti-Pescara , Chieti , Italy
| | - Daniela Rivanera
- c Department of Public Health and Infectious Diseases , Sapienza University of Rome , Rome , Italy
| | - Claudia Bordón
- d Stanley Division of Developmental Neurovirology , Johns Hopkins University School of Medicine , Baltimore , MD , USA
| | - Lorraine Jones-Brando
- d Stanley Division of Developmental Neurovirology , Johns Hopkins University School of Medicine , Baltimore , MD , USA
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15
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Alday PH, Doggett JS. Drugs in development for toxoplasmosis: advances, challenges, and current status. DRUG DESIGN DEVELOPMENT AND THERAPY 2017; 11:273-293. [PMID: 28182168 PMCID: PMC5279849 DOI: 10.2147/dddt.s60973] [Citation(s) in RCA: 181] [Impact Index Per Article: 25.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Indexed: 12/14/2022]
Abstract
Toxoplasma gondii causes fatal and debilitating brain and eye diseases. Medicines that are currently used to treat toxoplasmosis commonly have toxic side effects and require prolonged courses that range from weeks to more than a year. The need for long treatment durations and the risk of relapsing disease are in part due to the lack of efficacy against T. gondii tissue cysts. The challenges for developing a more effective treatment for toxoplasmosis include decreasing toxicity, achieving therapeutic concentrations in the brain and eye, shortening duration, eliminating tissue cysts from the host, safety in pregnancy, and creating a formulation that is inexpensive and practical for use in resource-poor areas of the world. Over the last decade, significant progress has been made in identifying and developing new compounds for the treatment of toxoplasmosis. Unlike clinically used medicines that were repurposed for toxoplasmosis, these compounds have been optimized for efficacy against toxoplasmosis during preclinical development. Medicines with enhanced efficacy as well as features that address the unique aspects of toxoplasmosis have the potential to greatly improve toxoplasmosis therapy. This review discusses the facets of toxoplasmosis that are pertinent to drug design and the advances, challenges, and current status of preclinical drug research for toxoplasmosis.
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Affiliation(s)
- P Holland Alday
- Division of Infectious Diseases, Oregon Health & Science University
| | - Joseph Stone Doggett
- Division of Infectious Diseases, Oregon Health & Science University; Portland Veterans Affairs Medical Center, Portland, OR, USA
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16
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Montazeri M, Sharif M, Sarvi S, Mehrzadi S, Ahmadpour E, Daryani A. A Systematic Review of In vitro and In vivo Activities of Anti -Toxoplasma Drugs and Compounds (2006-2016). Front Microbiol 2017; 8:25. [PMID: 28163699 PMCID: PMC5247447 DOI: 10.3389/fmicb.2017.00025] [Citation(s) in RCA: 96] [Impact Index Per Article: 13.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/01/2016] [Accepted: 01/05/2017] [Indexed: 11/23/2022] Open
Abstract
The currently available anti-Toxoplasma agents have serious limitations. This systematic review was performed to evaluate drugs and new compounds used for the treatment of toxoplasmosis. Data was systematically collected from published papers on the efficacy of drugs/compounds used against Toxoplasma gondii (T. gondii) globally during 2006-2016. The searched databases were PubMed, Google Scholar, Science Direct, ISI Web of Science, EBSCO, and Scopus. One hundred and eighteen papers were eligible for inclusion in this systematic review, which were both in vitro and in vivo studies. Within this review, 80 clinically available drugs and a large number of new compounds with more than 39 mechanisms of action were evaluated. Interestingly, many of the drugs/compounds evaluated against T. gondii act on the apicoplast. Therefore, the apicoplast represents as a potential drug target for new chemotherapy. Based on the current findings, 49 drugs/compounds demonstrated in vitro half-maximal inhibitory concentration (IC50) values of below 1 μM, but most of them were not evaluated further for in vivo effectiveness. However, the derivatives of the ciprofloxacin, endochin-like quinolones and 1-[4-(4-nitrophenoxy) phenyl] propane-1-one (NPPP) were significantly active against T. gondii tachyzoites both in vitro and in vivo. Thus, these compounds are promising candidates for future studies. Also, compound 32 (T. gondii calcium-dependent protein kinase 1 inhibitor), endochin-like quinolones, miltefosine, rolipram abolish, and guanabenz can be repurposed into an effective anti-parasitic with a unique ability to reduce brain tissue cysts (88.7, 88, 78, 74, and 69%, respectively). Additionally, no promising drugs are available for congenital toxoplasmosis. In conclusion, as current chemotherapy against toxoplasmosis is still not satisfactory, development of well-tolerated and safe specific immunoprophylaxis in relaxing the need of dependence on chemotherapeutics is a highly valuable goal for global disease control. However, with the increasing number of high-risk individuals, and absence of a proper vaccine, continued efforts are necessary for the development of novel treatment options against T. gondii. Some of the novel compounds reviewed here may represent good starting points for the discovery of effective new drugs. In further, bioinformatic and in silico studies are needed in order to identify new potential toxoplasmicidal drugs.
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Affiliation(s)
- Mahbobeh Montazeri
- Toxoplasmosis Research Center, Mazandaran University of Medical SciencesSari, Iran
- Student Research Committee, Mazandaran University of Medical SciencesSari, Iran
| | - Mehdi Sharif
- Toxoplasmosis Research Center, Mazandaran University of Medical SciencesSari, Iran
- Department of Parasitology and Mycology, Sari Medical School, Mazandaran University of Medical SciencesSari, Iran
| | - Shahabeddin Sarvi
- Toxoplasmosis Research Center, Mazandaran University of Medical SciencesSari, Iran
- Department of Parasitology and Mycology, Sari Medical School, Mazandaran University of Medical SciencesSari, Iran
| | - Saeed Mehrzadi
- Department of Pharmacology, School of Medicine, Iran University of Medical Sciences TehranIran
| | - Ehsan Ahmadpour
- Drug Applied Research Center, Tabriz University of Medical SciencesTabriz, Iran
| | - Ahmad Daryani
- Toxoplasmosis Research Center, Mazandaran University of Medical SciencesSari, Iran
- Department of Parasitology and Mycology, Sari Medical School, Mazandaran University of Medical SciencesSari, Iran
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17
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Welsch ME, Zhou J, Gao Y, Yan Y, Porter G, Agnihotri G, Li Y, Lu H, Chen Z, Thomas SB. Discovery of Potent and Selective Leads against Toxoplasma gondii Dihydrofolate Reductase via Structure-Based Design. ACS Med Chem Lett 2016; 7:1124-1129. [PMID: 27994750 DOI: 10.1021/acsmedchemlett.6b00328] [Citation(s) in RCA: 18] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/17/2016] [Accepted: 09/16/2016] [Indexed: 11/28/2022] Open
Abstract
Current treatment of toxoplasmosis targets the parasite's folate metabolism through inhibition of dihydrofolate reductase (DHFR). The most widely used DHFR antagonist, pyrimethamine, was introduced over 60 years ago and is associated with toxicity that can be largely attributed to a similar affinity for parasite and human DHFR. Computational analysis of biochemical differences between Toxoplasma gondii and human DHFR enabled the design of inhibitors with both improved potency and selectivity. The approach described herein yielded TRC-19, a promising lead with an IC50 of 9 nM and 89-fold selectivity in favor of Toxoplasma gondii DHFR, as well as crystallographic data to substantiate in silico methodology. Overall, 50% of synthesized in silico designs met hit threshold criteria of IC50 < 10 μM and >2-fold selectivity favoring Toxoplasma gondii, further demonstrating the efficiency of our structure-based drug design approach.
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Affiliation(s)
- Matthew E. Welsch
- Turing Pharmaceuticals AG, Research & Development, 1177 Avenue of the Americas, 39th Floor, New York, New York 10036, United States
| | - Jian Zhou
- WuXi AppTec, International Discovery Service Unit & Research Service Division, 288 Fute Zhong Road, Waigaoqiao Free Trade Zone, Shanghai 200131, China
| | - Yueqiang Gao
- WuXi AppTec, International Discovery Service Unit & Research Service Division, 288 Fute Zhong Road, Waigaoqiao Free Trade Zone, Shanghai 200131, China
| | - Yunqing Yan
- WuXi AppTec, International Discovery Service Unit & Research Service Division, 288 Fute Zhong Road, Waigaoqiao Free Trade Zone, Shanghai 200131, China
| | - Gene Porter
- WuXi AppTec, In Vitro Biology US, 107 Morgan Lane, Plainsborough, New Jersey 08536, United States
| | - Gautam Agnihotri
- WuXi AppTec, In Vitro Biology US, 107 Morgan Lane, Plainsborough, New Jersey 08536, United States
| | - Yingjie Li
- WuXi AppTec, International Discovery Service Unit & Research Service Division, 288 Fute Zhong Road, Waigaoqiao Free Trade Zone, Shanghai 200131, China
| | - Henry Lu
- WuXi AppTec, International Discovery Service Unit & Research Service Division, 288 Fute Zhong Road, Waigaoqiao Free Trade Zone, Shanghai 200131, China
| | - Zhongguo Chen
- WuXi AppTec, International Discovery Service Unit & Research Service Division, 288 Fute Zhong Road, Waigaoqiao Free Trade Zone, Shanghai 200131, China
| | - Stephen B. Thomas
- Turing Pharmaceuticals AG, Research & Development, 1177 Avenue of the Americas, 39th Floor, New York, New York 10036, United States
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18
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Review of Experimental Compounds Demonstrating Anti-Toxoplasma Activity. Antimicrob Agents Chemother 2016; 60:7017-7034. [PMID: 27600037 DOI: 10.1128/aac.01176-16] [Citation(s) in RCA: 28] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/11/2023] Open
Abstract
Toxoplasma gondii is a ubiquitous apicomplexan parasite capable of infecting humans and other animals. Current treatment options for T. gondii infection are limited and most have drawbacks, including high toxicity and low tolerability. Additionally, no FDA-approved treatments are available for pregnant women, a high-risk population due to transplacental infection. Therefore, the development of novel treatment options is needed. To aid this effort, this review highlights experimental compounds that, at a minimum, demonstrate inhibition of in vitro growth of T. gondii When available, host cell toxicity and in vivo data are also discussed. The purpose of this review is to facilitate additional development of anti-Toxoplasma compounds and potentially to extend our knowledge of the parasite.
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19
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McPhillie M, Zhou Y, El Bissati K, Dubey J, Lorenzi H, Capper M, Lukens AK, Hickman M, Muench S, Verma SK, Weber CR, Wheeler K, Gordon J, Sanders J, Moulton H, Wang K, Kim TK, He Y, Santos T, Woods S, Lee P, Donkin D, Kim E, Fraczek L, Lykins J, Esaa F, Alibana-Clouser F, Dovgin S, Weiss L, Brasseur G, Wirth D, Kent M, Hood L, Meunieur B, Roberts CW, Hasnain SS, Antonyuk SV, Fishwick C, McLeod R. New paradigms for understanding and step changes in treating active and chronic, persistent apicomplexan infections. Sci Rep 2016; 6:29179. [PMID: 27412848 PMCID: PMC4944145 DOI: 10.1038/srep29179] [Citation(s) in RCA: 29] [Impact Index Per Article: 3.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/01/2016] [Accepted: 05/31/2016] [Indexed: 12/24/2022] Open
Abstract
Toxoplasma gondii, the most common parasitic infection of human brain and eye, persists across lifetimes, can progressively damage sight, and is currently incurable. New, curative medicines are needed urgently. Herein, we develop novel models to facilitate drug development: EGS strain T. gondii forms cysts in vitro that induce oocysts in cats, the gold standard criterion for cysts. These cysts highly express cytochrome b. Using these models, we envisioned, and then created, novel 4-(1H)-quinolone scaffolds that target the cytochrome bc1 complex Qi site, of which, a substituted 5,6,7,8-tetrahydroquinolin-4-one inhibits active infection (IC50, 30 nM) and cysts (IC50, 4 μM) in vitro, and in vivo (25 mg/kg), and drug resistant Plasmodium falciparum (IC50, <30 nM), with clinically relevant synergy. Mutant yeast and co-crystallographic studies demonstrate binding to the bc1 complex Qi site. Our results have direct impact on improving outcomes for those with toxoplasmosis, malaria, and ~2 billion persons chronically infected with encysted bradyzoites.
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Affiliation(s)
| | | | | | | | | | | | - Amanda K Lukens
- Harvard School of Public Health, Boston, Massachusetts, USA
- The Broad Institute, Boston, Massachusetts, USA
| | - Mark Hickman
- Walter Reed Army Institute of Research, Silver Spring, Maryland, USA
| | | | | | | | | | | | | | | | - Kai Wang
- Institute for Systems Biology, Seattle, Washington, USA
| | - Taek-Kyun Kim
- Institute for Systems Biology, Seattle, Washington, USA
| | - Yuqing He
- Institute for Systems Biology, Seattle, Washington, USA
| | - Tatiana Santos
- Albert Einstein College of Medicine, Bronx, New York, USA
| | | | - Patty Lee
- Walter Reed Army Institute of Research, Silver Spring, Maryland, USA
| | - David Donkin
- Walter Reed Army Institute of Research, Silver Spring, Maryland, USA
| | - Eric Kim
- Walter Reed Army Institute of Research, Silver Spring, Maryland, USA
| | | | | | | | | | | | - Louis Weiss
- Albert Einstein College of Medicine, Bronx, New York, USA
| | | | - Dyann Wirth
- Harvard School of Public Health, Boston, Massachusetts, USA
- The Broad Institute, Boston, Massachusetts, USA
| | | | - Leroy Hood
- Institute for Systems Biology, Seattle, Washington, USA
| | - Brigitte Meunieur
- Institute for Integrative Biology of the Cell (12BC), Gif-sur-Yvette, France
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20
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Lim SSY, Othman RY. Recent advances in Toxoplasma gondii immunotherapeutics. THE KOREAN JOURNAL OF PARASITOLOGY 2014; 52:581-93. [PMID: 25548409 PMCID: PMC4277020 DOI: 10.3347/kjp.2014.52.6.581] [Citation(s) in RCA: 32] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 04/03/2014] [Revised: 08/21/2014] [Accepted: 08/22/2014] [Indexed: 12/11/2022]
Abstract
Toxoplasmosis is an opportunistic infection caused by the protozoan parasite Toxoplasma gondii. T. gondii is widespread globally and causes severe diseases in individuals with impaired immune defences as well as congenitally infected infants. The high prevalence rate in some parts of the world such as South America and Africa, coupled with the current drug treatments that trigger hypersensitivity reactions, makes the development of immunotherapeutics intervention a highly important research priority. Immunotherapeutics strategies could either be a vaccine which would confer a pre-emptive immunity to infection, or passive immunization in cases of disease recrudescence or recurrent clinical diseases. As the severity of clinical manifestations is often greater in developing nations, the development of well-tolerated and safe immunotherapeutics becomes not only a scientific pursuit, but a humanitarian enterprise. In the last few years, much progress has been made in vaccine research with new antigens, novel adjuvants, and innovative vaccine delivery such as nanoparticles and antigen encapsulations. A literature search over the past 5 years showed that most experimental studies were focused on DNA vaccination at 52%, followed by protein vaccination which formed 36% of the studies, live attenuated vaccinations at 9%, and heterologous vaccination at 3%; while there were few on passive immunization. Recent progress in studies on vaccination, passive immunization, as well as insights gained from these immunotherapeutics is highlighted in this review.
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Affiliation(s)
- Sherene Swee-Yin Lim
- Genetics and Molecular Biology Department, Institute of Biological Sciences, Faculty of Science, University of Malaya, 50603, Kuala Lumpur, Malaysia
| | - Rofina Yasmin Othman
- Genetics and Molecular Biology Department, Institute of Biological Sciences, Faculty of Science, University of Malaya, 50603, Kuala Lumpur, Malaysia. ; Centre for Research in Biotechnology for Agriculture, University of Malaya, 50603 Kuala Lumpur, Malaysia
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21
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Triclosan and triclosan-loaded liposomal nanoparticles in the treatment of acute experimental toxoplasmosis. Exp Parasitol 2014; 149:54-64. [PMID: 25499511 DOI: 10.1016/j.exppara.2014.12.007] [Citation(s) in RCA: 32] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/06/2014] [Revised: 11/26/2014] [Accepted: 12/04/2014] [Indexed: 11/21/2022]
Abstract
Efficacy of triclosan (TS) and TS-loaded liposomes against the virulent strain of Toxoplasma gondii (T. gondii) was evaluated. Swiss albino mice were intraperitoneally infected with 10(4) tachyzoites of RH HXGPRT(-) strain of T. gondii, then were orally treated with 150 mg/kg TS or 100 mg/kg TS liposomes twice daily for 4 days. Mice mortality, peritoneal and liver parasite burdens, viability, infectivity and ultrastructural changes of peritoneal tachyzoites of infected treated mice were studied, in comparison with those of infected non-treated controls. Drug safety was biochemically assessed by measuring liver enzymes and thyroxin. Both TS and TS liposomes induced significant reduction in mice mortality, parasite burden, viability and infectivity of tachyzoites harvested from infected treated mice. Scanning electron microscopy of treated tachyzoites showed distorted shapes, reduced sizes, irregularities, surface protrusions, erosions and peeling besides apical region distortion. Transmission electron microscopy showed that treated tachyzoites were intracellularly distorted, had cytoplasmic vacuolation, discontinuous plasma membranes, nuclear abnormalities and disrupted internal structures. Besides, in TS liposomes-treated subgroup, most tachyzoites were seen intracellularly with complete disintegration of the parasite plasma and nuclear membranes, with complete destruction of the internal structures. Biochemical safety of TS and TS liposomes was proven. Accordingly, TS can be considered as a promising alternative to the standard therapy for treating acute murine toxoplasmosis. Liposomal formulation of TS enhanced its efficacy and allowed its use in a lower dose.
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22
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Design, synthesis and biological characterization of thiazolidin-4-one derivatives as promising inhibitors of Toxoplasma gondii. Eur J Med Chem 2014; 86:17-30. [PMID: 25140751 DOI: 10.1016/j.ejmech.2014.08.046] [Citation(s) in RCA: 33] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/21/2014] [Revised: 08/13/2014] [Accepted: 08/14/2014] [Indexed: 11/21/2022]
Abstract
We designed and synthesized a large number of novel thiazolidin-4-one derivatives for the evaluation of their anti-Toxoplasma gondii activity. This scaffold was functionalized at the N1-hydrazine portion with aliphatic, cycloaliphatic and (hetero)aromatic moieties. Then, a benzyl pendant was introduced at the lactamic NH of the core nucleus to evaluate the influence of this chemical modification on biological activity. The compounds were subjected to several in vitro assays to assess their anti-parasitic efficacy, cytotoxicity on fibroblasts, inhibition of tachyzoite invasion/attachment and replication after treatment. Results showed that fourteen of these thiazole-based compounds compare favorably to control compound trimethoprim in terms of parasite growth inhibition.
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24
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Pop MS, Stransky N, Garvie CW, Theurillat JP, Hartman EC, Lewis TA, Zhong C, Culyba EK, Lin F, Daniels DS, Pagliarini R, Ronco L, Koehler AN, Garraway LA. A small molecule that binds and inhibits the ETV1 transcription factor oncoprotein. Mol Cancer Ther 2014; 13:1492-502. [PMID: 24737027 DOI: 10.1158/1535-7163.mct-13-0689] [Citation(s) in RCA: 41] [Impact Index Per Article: 4.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/16/2022]
Abstract
Members of the ETS transcription factor family have been implicated in several cancers, where they are often dysregulated by genomic derangement. ETS variant 1 (ETV1) is an ETS factor gene that undergoes chromosomal translocation in prostate cancers and Ewing sarcomas, amplification in melanomas, and lineage dysregulation in gastrointestinal stromal tumors. Pharmacologic perturbation of ETV1 would be appealing in these cancers; however, oncogenic transcription factors are often deemed "undruggable" by conventional methods. Here, we used small-molecule microarray screens to identify and characterize drug-like compounds that modulate the biologic function of ETV1. We identified the 1,3,5-triazine small molecule BRD32048 as a top candidate ETV1 perturbagen. BRD32048 binds ETV1 directly, modulating both ETV1-mediated transcriptional activity and invasion of ETV1-driven cancer cells. Moreover, BRD32048 inhibits p300-dependent acetylation of ETV1, thereby promoting its degradation. These results point to a new avenue for pharmacologic ETV1 inhibition and may inform a general means to discover small molecule perturbagens of transcription factor oncoproteins.
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Affiliation(s)
- Marius S Pop
- Authors' Affiliations: Dana Farber Cancer Institute, Boston; Broad Institute; Novartis Institute for Biomedical Research; Department of Biological Engineering; and Koch Institute for Integrative Cancer Research, MIT, Cambridge, MassachusettsAuthors' Affiliations: Dana Farber Cancer Institute, Boston; Broad Institute; Novartis Institute for Biomedical Research; Department of Biological Engineering; and Koch Institute for Integrative Cancer Research, MIT, Cambridge, Massachusetts
| | - Nicolas Stransky
- Authors' Affiliations: Dana Farber Cancer Institute, Boston; Broad Institute; Novartis Institute for Biomedical Research; Department of Biological Engineering; and Koch Institute for Integrative Cancer Research, MIT, Cambridge, Massachusetts
| | - Colin W Garvie
- Authors' Affiliations: Dana Farber Cancer Institute, Boston; Broad Institute; Novartis Institute for Biomedical Research; Department of Biological Engineering; and Koch Institute for Integrative Cancer Research, MIT, Cambridge, Massachusetts
| | - Jean-Philippe Theurillat
- Authors' Affiliations: Dana Farber Cancer Institute, Boston; Broad Institute; Novartis Institute for Biomedical Research; Department of Biological Engineering; and Koch Institute for Integrative Cancer Research, MIT, Cambridge, MassachusettsAuthors' Affiliations: Dana Farber Cancer Institute, Boston; Broad Institute; Novartis Institute for Biomedical Research; Department of Biological Engineering; and Koch Institute for Integrative Cancer Research, MIT, Cambridge, Massachusetts
| | - Emily C Hartman
- Authors' Affiliations: Dana Farber Cancer Institute, Boston; Broad Institute; Novartis Institute for Biomedical Research; Department of Biological Engineering; and Koch Institute for Integrative Cancer Research, MIT, Cambridge, Massachusetts
| | - Timothy A Lewis
- Authors' Affiliations: Dana Farber Cancer Institute, Boston; Broad Institute; Novartis Institute for Biomedical Research; Department of Biological Engineering; and Koch Institute for Integrative Cancer Research, MIT, Cambridge, Massachusetts
| | - Cheng Zhong
- Authors' Affiliations: Dana Farber Cancer Institute, Boston; Broad Institute; Novartis Institute for Biomedical Research; Department of Biological Engineering; and Koch Institute for Integrative Cancer Research, MIT, Cambridge, Massachusetts
| | - Elizabeth K Culyba
- Authors' Affiliations: Dana Farber Cancer Institute, Boston; Broad Institute; Novartis Institute for Biomedical Research; Department of Biological Engineering; and Koch Institute for Integrative Cancer Research, MIT, Cambridge, Massachusetts
| | - Fallon Lin
- Authors' Affiliations: Dana Farber Cancer Institute, Boston; Broad Institute; Novartis Institute for Biomedical Research; Department of Biological Engineering; and Koch Institute for Integrative Cancer Research, MIT, Cambridge, Massachusetts
| | - Douglas S Daniels
- Authors' Affiliations: Dana Farber Cancer Institute, Boston; Broad Institute; Novartis Institute for Biomedical Research; Department of Biological Engineering; and Koch Institute for Integrative Cancer Research, MIT, Cambridge, Massachusetts
| | - Raymond Pagliarini
- Authors' Affiliations: Dana Farber Cancer Institute, Boston; Broad Institute; Novartis Institute for Biomedical Research; Department of Biological Engineering; and Koch Institute for Integrative Cancer Research, MIT, Cambridge, Massachusetts
| | - Lucienne Ronco
- Authors' Affiliations: Dana Farber Cancer Institute, Boston; Broad Institute; Novartis Institute for Biomedical Research; Department of Biological Engineering; and Koch Institute for Integrative Cancer Research, MIT, Cambridge, Massachusetts
| | - Angela N Koehler
- Authors' Affiliations: Dana Farber Cancer Institute, Boston; Broad Institute; Novartis Institute for Biomedical Research; Department of Biological Engineering; and Koch Institute for Integrative Cancer Research, MIT, Cambridge, MassachusettsAuthors' Affiliations: Dana Farber Cancer Institute, Boston; Broad Institute; Novartis Institute for Biomedical Research; Department of Biological Engineering; and Koch Institute for Integrative Cancer Research, MIT, Cambridge, MassachusettsAuthors' Affiliations: Dana Farber Cancer Institute, Boston; Broad Institute; Novartis Institute for Biomedical Research; Department of Biological Engineering; and Koch Institute for Integrative Cancer Research, MIT, Cambridge, Massachusetts
| | - Levi A Garraway
- Authors' Affiliations: Dana Farber Cancer Institute, Boston; Broad Institute; Novartis Institute for Biomedical Research; Department of Biological Engineering; and Koch Institute for Integrative Cancer Research, MIT, Cambridge, MassachusettsAuthors' Affiliations: Dana Farber Cancer Institute, Boston; Broad Institute; Novartis Institute for Biomedical Research; Department of Biological Engineering; and Koch Institute for Integrative Cancer Research, MIT, Cambridge, Massachusetts
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25
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Spiroindolone that inhibits PfATPase4 is a potent, cidal inhibitor of Toxoplasma gondii tachyzoites in vitro and in vivo. Antimicrob Agents Chemother 2013; 58:1789-92. [PMID: 24366743 DOI: 10.1128/aac.02225-13] [Citation(s) in RCA: 22] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022] Open
Abstract
Here, we show that spiroindolone, an effective treatment for plasmodia, is also active against Toxoplasma gondii tachyzoites. In vitro, spiroindolone NITD609 is cidal for tachyzoites (50% inhibitory concentration [IC50], 1μM) and not toxic to human cells at ≥10μM. Two daily oral doses of 100 mg/kg of body weight reduced the parasite burden in mice by 90% (P=0.002), measured 3 days after the last dose. This inhibition of T. gondii tachyzoites in vitro and in vivo indicates that spiroindolone is a promising lead candidate for further medicine development.
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26
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Donor CD8+ T cells prevent Toxoplasma gondii de-encystation but fail to rescue the exhausted endogenous CD8+ T cell population. Infect Immun 2013; 81:3414-25. [PMID: 23817617 DOI: 10.1128/iai.00784-12] [Citation(s) in RCA: 21] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/07/2023] Open
Abstract
Functional exhaustion of CD8(+) T cells due to increased expression of inhibitory molecule PD-1 (Programmed Death-1) causes reactivation of latent disease during later phases of chronic toxoplasmosis. Onset of disease recrudescence results in decreased parasite cyst burden concomitant with parasites undergoing stage conversion from a primarily encysted, quiescent bradyzoite to a fast-replicating, highly motile tachyzoite. Thus, reduced cyst burden is one of the early hallmarks of disease recrudescence. This was further validated by depleting gamma interferon (IFN-γ), a cytokine known to control latent toxoplasmosis, in chronically infected prerecrudescent mice. Since CD8(+) T cells (an important source of IFN-γ) lose their functionality during the later phases of chronic toxoplasmosis, we next examined if adoptive transfer of functional CD8(+) T cells from acutely infected donors to the chronically infected prerecrudescent hosts could impede parasite de-encystation and rescue exhausted CD8(+) T cells. While the transfer of immune CD8(+) T cells temporarily restricted the breakdown of cysts, the exhausted endogenous CD8(+) T cell population was not rescued. Over time, the donor population got deleted, resulting in parasite de-encystation and host mortality. Considering that donor CD8(+) T cells fail to become long-lived, one of the cardinal features of memory CD8(+) T cells, it bears the implication that memory CD8 differentiation is impaired during chronic toxoplasmosis. Moreover, our data strongly suggest that while adoptive immunotherapy can prevent parasite de-encystation transiently, reduced antigen burden in the chronic phase by itself is insufficient for rescue of exhausted CD8(+) T cells. The conclusions of this study have profound ramifications in designing immunotherapeutics against chronic toxoplasmosis.
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Stec J, Fomovska A, Afanador GA, Muench SP, Zhou Y, Lai BS, El Bissati K, Hickman MR, Lee PJ, Leed SE, Auschwitz JM, Sommervile C, Woods S, Roberts CW, Rice D, Prigge ST, McLeod R, Kozikowski AP. Modification of triclosan scaffold in search of improved inhibitors for enoyl-acyl carrier protein (ACP) reductase in Toxoplasma gondii. ChemMedChem 2013; 8:1138-60. [PMID: 23776166 DOI: 10.1002/cmdc.201300050] [Citation(s) in RCA: 18] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/01/2013] [Revised: 04/26/2013] [Indexed: 11/08/2022]
Abstract
Through our focused effort to discover new and effective agents against toxoplasmosis, a structure-based drug design approach was used to develop a series of potent inhibitors of the enoyl-acyl carrier protein (ACP) reductase (ENR) enzyme in Toxoplasma gondii (TgENR). Modifications to positions 5 and 4' of the well-known ENR inhibitor triclosan afforded a series of 29 new analogues. Among the resulting compounds, many showed high potency and improved physicochemical properties in comparison with the lead. The most potent compounds 16 a and 16 c have IC50 values of 250 nM against Toxoplasma gondii tachyzoites without apparent toxicity to the host cells. Their IC50 values against recombinant TgENR were found to be 43 and 26 nM, respectively. Additionally, 11 other analogues in this series had IC50 values ranging from 17 to 130 nM in the enzyme-based assay. With respect to their excellent in vitro activity as well as improved drug-like properties, the lead compounds 16 a and 16 c are deemed to be excellent starting points for the development of new medicines to effectively treat Toxoplasma gondii infections.
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Affiliation(s)
- Jozef Stec
- Drug Discovery Program, Department of Medicinal Chemistry and Pharmacognosy, University of Illinois at Chicago, 833 South Wood Street, Chicago, IL 60612, USA
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Wallon M, Peyron F, Cornu C, Vinault S, Abrahamowicz M, Kopp CB, Binquet C. CongenitalToxoplasmaInfection: Monthly Prenatal Screening Decreases Transmission Rate and Improves Clinical Outcome at Age 3 Years. Clin Infect Dis 2013; 56:1223-31. [DOI: 10.1093/cid/cit032] [Citation(s) in RCA: 152] [Impact Index Per Article: 13.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/15/2022] Open
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Song T, Li X, Chang X, Liang X, Zhao Y, Wu G, Xie S, Su P, Wu Z, Feng Y, Zhang Z. 3-Thiomorpholin-8-oxo-8H-acenaphtho [1,2-b] pyrrole-9-carbonitrile (S1) derivatives as pan-Bcl-2-inhibitors of Bcl-2, Bcl-xL and Mcl-1. Bioorg Med Chem 2012. [PMID: 23206987 DOI: 10.1016/j.bmc.2012.11.008] [Citation(s) in RCA: 27] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/04/2023]
Abstract
Based on the binding mode of our previously discovered dual inhibitor of Bcl-2 and Mcl-1, 3-thiomorpholin-8-oxo-8H-acenaphtho[1,2-b]pyrrole-9-carbonitrile (3, S1), a library of 9-substituted 3 derivatives was synthesized to further probe the p4 pocket of the two targets. By NMR, structure-activity relationship study, and site-directed mutation, compound 6d (3-(4-aminophenylthio)-8-oxo-8H-acenaphtho[1,2-b]pyrrole-9-3-phenyl)propylamine) was identified to span p2-p4 pockets of Mcl-1, Bcl-2 and Bcl-x(L), and then exhibited 9- to 35-fold better affinity to the three targets than 3 (IC(50)=10, 20 and 18 nM, respectively), which led to greater activity in induction of apoptosis in multiple cancer cell lines. Different contribution of p4 pocket to binding Bcl-2 and Mcl-1 was also investigated by plotting the potency and the HAC of the derivatives.
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Affiliation(s)
- Ting Song
- State Key Laboratory of Fine Chemicals, School of Chemistry, Dalian University of Technology, Dalian 116012, People's Republic of China
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Novel N-benzoyl-2-hydroxybenzamide disrupts unique parasite secretory pathway. Antimicrob Agents Chemother 2012; 56:2666-82. [PMID: 22354304 DOI: 10.1128/aac.06450-11] [Citation(s) in RCA: 26] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/22/2023] Open
Abstract
Toxoplasma gondii is a protozoan parasite that can damage the human brain and eyes. There are no curative medicines. Herein, we describe our discovery of N-benzoyl-2-hydroxybenzamides as a class of compounds effective in the low nanomolar range against T. gondii in vitro and in vivo. Our lead compound, QQ-437, displays robust activity against the parasite and could be useful as a new scaffold for development of novel and improved inhibitors of T. gondii. Our genome-wide investigations reveal a specific mechanism of resistance to N-benzoyl-2-hydroxybenzamides mediated by adaptin-3β, a large protein from the secretory protein complex. N-Benzoyl-2-hydroxybenzamide-resistant clones have alterations of their secretory pathway, which traffics proteins to micronemes, rhoptries, dense granules, and acidocalcisomes/plant-like vacuole (PLVs). N-Benzoyl-2-hydroxybenzamide treatment also alters micronemes, rhoptries, the contents of dense granules, and, most markedly, acidocalcisomes/PLVs. Furthermore, QQ-437 is active against chloroquine-resistant Plasmodium falciparum. Our studies reveal a novel class of compounds that disrupts a unique secretory pathway of T. gondii, with the potential to be used as scaffolds in the search for improved compounds to treat the devastating diseases caused by apicomplexan parasites.
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Jin C, Jung SY, Kim SY, Song HO, Park H. Simple and efficient model systems of screening anti-Toxoplasmadrugsin vitro. Expert Opin Drug Discov 2012; 7:195-205. [DOI: 10.1517/17460441.2012.660479] [Citation(s) in RCA: 11] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/05/2022]
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Prediction of residues involved in inhibitor specificity in the dihydrofolate reductase family. BIOCHIMICA ET BIOPHYSICA ACTA-PROTEINS AND PROTEOMICS 2011; 1814:1870-9. [DOI: 10.1016/j.bbapap.2011.08.001] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/25/2011] [Revised: 07/29/2011] [Accepted: 08/01/2011] [Indexed: 12/11/2022]
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In vitro activity of JPC 2067 alone and in combination with sulfamethoxazole against nocardia species. Antimicrob Agents Chemother 2011; 56:1133-4. [PMID: 22106219 DOI: 10.1128/aac.05855-11] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022] Open
Abstract
JPC 2067 is a novel dihydrotriazine dihydrofolate reductase inhibitor that is being developed as an antimalarial therapeutic. We evaluated the in vitro activity of JPC 2067 alone and in combination with sulfamethoxazole (SMX) against a panel of nocardia isolates. The MIC(50)s and MIC(90)s for JPC 2067, SMX, and the combination were 0.125 μg/ml and 4 μg/ml, 16 μg/ml and 32 μg/ml, and 0.03 μg/ml and 2 μg/ml, respectively. JPC 2067 alone and in combination with SMX should be evaluated further to understand its clinical potential.
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Stillwaggon E, Carrier CS, Sautter M, McLeod R. Maternal serologic screening to prevent congenital toxoplasmosis: a decision-analytic economic model. PLoS Negl Trop Dis 2011; 5:e1333. [PMID: 21980546 PMCID: PMC3181241 DOI: 10.1371/journal.pntd.0001333] [Citation(s) in RCA: 72] [Impact Index Per Article: 5.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/12/2011] [Accepted: 08/10/2011] [Indexed: 11/19/2022] Open
Abstract
OBJECTIVE To determine a cost-minimizing option for congenital toxoplasmosis in the United States. METHODOLOGY/PRINCIPAL FINDINGS A decision-analytic and cost-minimization model was constructed to compare monthly maternal serological screening, prenatal treatment, and post-natal follow-up and treatment according to the current French (Paris) protocol, versus no systematic screening or perinatal treatment. Costs are based on published estimates of lifetime societal costs of developmental disabilities and current diagnostic and treatment costs. Probabilities are based on published results and clinical practice in the United States and France. One- and two-way sensitivity analyses are used to evaluate robustness of results. Universal monthly maternal screening for congenital toxoplasmosis with follow-up and treatment, following the French protocol, is found to be cost-saving, with savings of $620 per child screened. Results are robust to changes in test costs, value of statistical life, seroprevalence in women of childbearing age, fetal loss due to amniocentesis, and to bivariate analysis of test costs and incidence of primary T. gondii infection in pregnancy. Given the parameters in this model and a maternal screening test cost of $12, screening is cost-saving for rates of congenital infection above 1 per 10,000 live births. If universal testing generates economies of scale in diagnostic tools-lowering test costs to about $2 per test-universal screening is cost-saving at rates of congenital infection well below the lowest reported rates in the United States of 1 per 10,000 live births. CONCLUSION/SIGNIFICANCE Universal screening according to the French protocol is cost saving for the US population within broad parameters for costs and probabilities.
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Affiliation(s)
- Eileen Stillwaggon
- Department of Economics, Gettysburg College, Gettysburg, Pennsylvania, USA.
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Rapid discovery of inhibitors of Toxoplasma gondii using hybrid structure-based computational approach. J Comput Aided Mol Des 2011; 25:403-11. [DOI: 10.1007/s10822-011-9420-6] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/23/2010] [Accepted: 02/16/2011] [Indexed: 10/18/2022]
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Hutson SL, Mui E, Kinsley K, Witola WH, Behnke MS, El Bissati K, Muench SP, Rohrman B, Liu SR, Wollmann R, Ogata Y, Sarkeshik A, Yates JR, McLeod R. T. gondii RP promoters & knockdown reveal molecular pathways associated with proliferation and cell-cycle arrest. PLoS One 2010; 5:e14057. [PMID: 21124925 PMCID: PMC2989910 DOI: 10.1371/journal.pone.0014057] [Citation(s) in RCA: 20] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/03/2010] [Accepted: 10/25/2010] [Indexed: 01/16/2023] Open
Abstract
Molecular pathways regulating rapid proliferation and persistence are fundamental for pathogens but are not elucidated fully in Toxoplasma gondii. Promoters of T. gondii ribosomal proteins (RPs) were analyzed by EMSAs and ChIP. One RP promoter domain, known to bind an Apetela 2, bound to nuclear extract proteins. Promoter domains appeared to associate with histone acetyl transferases. To study effects of a RP gene's regulation in T. gondii, mutant parasites (Δrps13) were engineered with integration of tetracycline repressor (TetR) response elements in a critical location in the rps13 promoter and transfection of a yellow fluorescent-tetracycline repressor (YFP-TetR). This permitted conditional knockdown of rps13 expression in a tightly regulated manner. Δrps13 parasites were studied in the presence (+ATc) or absence of anhydrotetracycline (-ATc) in culture. -ATc, transcription of the rps13 gene and expression of RPS13 protein were markedly diminished, with concomitant cessation of parasite replication. Study of Δrps13 expressing Myc-tagged RPL22, -ATc, showed RPL22 diminished but at a slower rate. Quantitation of RNA showed diminution of 18S RNA. Depletion of RPS13 caused arrest of parasites in the G1 cell cycle phase, thereby stopping parasite proliferation. Transcriptional differences ±ATc implicate molecules likely to function in regulation of these processes. In vitro, -ATc, Δrps13 persists for months and the proliferation phenotype can be rescued with ATc. In vivo, however, Δrps13 could only be rescued when ATc was given simultaneously and not at any time after 1 week, even when L-NAME and ATc were administered. Immunization with Δrps13 parasites protects mice completely against subsequent challenge with wildtype clonal Type 1 parasites, and robustly protects mice against wildtype clonal Type 2 parasites. Our results demonstrate that G1 arrest by ribosomal protein depletion is associated with persistence of T. gondii in a model system in vitro and immunization with Δrps13 protects mice against subsequent challenge with wildtype parasites.
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Affiliation(s)
- Samuel L. Hutson
- Department of Surgery (Ophthalmology), The University of Chicago, Chicago, Illinois, United States of America
| | - Ernest Mui
- Department of Surgery (Ophthalmology), The University of Chicago, Chicago, Illinois, United States of America
| | - Karen Kinsley
- Department of Surgery (Ophthalmology), The University of Chicago, Chicago, Illinois, United States of America
| | - William H. Witola
- Department of Surgery (Ophthalmology), The University of Chicago, Chicago, Illinois, United States of America
| | - Michael S. Behnke
- Department of Veterinary Molecular Biology, Montana State University, Bozeman, Montana, United States of America
| | - Kamal El Bissati
- Department of Surgery (Ophthalmology), The University of Chicago, Chicago, Illinois, United States of America
| | - Stephen P. Muench
- Institute of Membrane and Systems Biology, University of Leeds, Leeds, United Kingdom
| | - Brittany Rohrman
- Department of Surgery (Ophthalmology), The University of Chicago, Chicago, Illinois, United States of America
| | - Susan R. Liu
- Department of Surgery (Ophthalmology), The University of Chicago, Chicago, Illinois, United States of America
| | - Robert Wollmann
- Department of Pathology, The University of Chicago, Chicago, Illinois, United States of America
| | - Yuko Ogata
- Seattle Biomedical Research Institute, Seattle, Washington, United States of America
| | - Ali Sarkeshik
- Department of Chemical Physiology, Scripps Research Institute, La Jolla, California, United States of America
| | - John R. Yates
- Department of Chemical Physiology, Scripps Research Institute, La Jolla, California, United States of America
| | - Rima McLeod
- Department of Surgery (Ophthalmology), The University of Chicago, Chicago, Illinois, United States of America
- Department of Pediatrics (Infectious Disease), The University of Chicago, Chicago, Illinois, United States of America
- Committees on Immunology, Molecular Medicine, and Genetics, Institute of Genomics and Systems Biology, The College, The University of Chicago, Chicago, Illinois, United States of America
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Hencken CP, Jones-Brando L, Bordón C, Stohler R, Mott BT, Yolken R, Posner GH, Woodard LE. Thiazole, oxadiazole, and carboxamide derivatives of artemisinin are highly selective and potent inhibitors of Toxoplasma gondii. J Med Chem 2010; 53:3594-601. [PMID: 20373807 DOI: 10.1021/jm901857d] [Citation(s) in RCA: 53] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Abstract
We have prepared 23 new dehydroartemisinin (DART) trioxane derivatives (11 thiazoles, 2 oxadiazoles, and 10 carboxamides) and have screened them for in vitro activity in the Toxoplasma lytic cycle. Fifteen (65%) of the derivatives were noncytotoxic to host cells (TD(50) > or = 320 microM). Eight thiazole derivatives and two carboxamide derivatives displayed effective inhibition of Toxoplasma growth (IC(50) = 0.25-0.42 microM), comparable in potency to artemether (IC(50) = 0.31 microM) and >100 times more inhibitory than the currently employed front-line drug trimethoprim (IC(50) = 46 microM). The thiazoles as a group were more effective than the other derivatives at inhibiting growth of extracellular as well as intracellular parasites. Unexpectedly, two thiazole trioxanes (5 and 6) were parasiticidal; both inhibited parasite replication irreversibly after parasite exposure to 10 microM of drug for 24 h, whereas the standard trioxane drugs artemisinin and artemether were not parasiticidal. Some of the new derivatives of artemisinin described here represent effective anti-Toxoplasma trioxanes as well as molecular probes for elucidating the mechanism of action of the DART class of artemisinin derivatives.
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Affiliation(s)
- Christopher P Hencken
- Department of Chemistry, The Johns Hopkins University, 3400 North Charles Street, Baltimore, Maryland 21218, USA.
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Adane L, Bharatam PV. Computer-aided molecular design of 1H-imidazole-2,4-diamine derivatives as potential inhibitors of Plasmodium falciparum DHFR enzyme. J Mol Model 2010; 17:657-67. [DOI: 10.1007/s00894-010-0756-y] [Citation(s) in RCA: 25] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/04/2010] [Accepted: 05/12/2010] [Indexed: 11/30/2022]
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Phenotypic and gene expression changes among clonal type I strains of Toxoplasma gondii. EUKARYOTIC CELL 2009; 8:1828-36. [PMID: 19801420 DOI: 10.1128/ec.00150-09] [Citation(s) in RCA: 52] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/20/2022]
Abstract
Toxoplasma gondii has an unusual population structure consisting of three clonal lineages that predominate in North America and Europe. This simple pattern has encouraged the use of only a few laboratory isolates that are representative of each lineage. Principle among these is the type I RH strain, originally isolated from a child with encephalitis some 70 years ago. Comparison of different passages of the RH strain that have been propagated differently over the intervening time period revealed that the commonly used clonal line called RH-ERP was not representative of natural isolates of the type I lineage. Notably, RH-ERP formed much larger plaques than other type 1 strains, including a separate, earlier derived isolate of the RH strain. The RH-ERP variant also showed enhanced extracellular survival, faster growth, and decreased differentiation compared to the prototype type I strain GT1. Comparison of gene expression differences in the RH-ERP line revealed that several ABC transporters were upregulated, which may provide a growth advantage in vitro. These findings illustrate that dramatic phenotypic changes can arise in laboratory strains, emphasizing the need for comparison with recent clinical isolates.
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McLeod R, Kieffer F, Sautter M, Hosten T, Pelloux H. Why prevent, diagnose and treat congenital toxoplasmosis? Mem Inst Oswaldo Cruz 2009; 104:320-44. [PMID: 19430661 PMCID: PMC2735102 DOI: 10.1590/s0074-02762009000200029] [Citation(s) in RCA: 109] [Impact Index Per Article: 7.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/10/2008] [Accepted: 10/20/2008] [Indexed: 11/21/2022] Open
Abstract
Evidence that prevention, diagnosis and treatment of toxoplasmosis is beneficial developed as follows: anti-parasitic agents abrogate Toxoplasma gondii tachyzoite growth, preventing destruction of infected, cultured, mammalian cells and cure active infections in experimental animals, including primates. They treat active infections in persons who are immune-compromised, limit destruction of retina by replicating parasites and thereby treat ocular toxoplasmosis and treat active infection in the fetus and infant. Outcomes of untreated congenital toxoplasmosis include adverse ocular and neurologic sequelae described in different countries and decades. Better outcomes are associated with treatment of infected infants throughout their first year of life. Shorter intervals between diagnosis and treatment in utero improve outcomes. A French approach for diagnosis and treatment of congenital toxoplasmosis in the fetus and infant can prevent toxoplasmosis and limit adverse sequelae. In addition, new data demonstrate that this French approach results in favorable outcomes with some early gestation infections. A standardized approach to diagnosis and treatment during gestation has not yet been applied generally in the USA. Nonetheless, a small, similar experience confirms that this French approach is feasible, safe, and results in favorable outcomes in the National Collaborative Chicago-based Congenital Toxoplasmosis Study cohort. Prompt diagnosis, prevention and treatment reduce adverse sequelae of congenital toxoplasmosis.
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Affiliation(s)
- Rima McLeod
- Department of Ophthalmology and Visual Sciences, Committees on Immunology, Genetics, Molecular Medicine, The College, University of Chicago, Chicago, IL 60637, USA.
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News updates. Lab Anim (NY) 2008. [DOI: 10.1038/laban0408-145] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/08/2022]
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