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Mohammad Rahimi H, Hesari Z, Mirsamadi ES, Nemati S, Mirjalali H. Anti- Toxoplasma gondii activity of rose hip oil-solid lipid nanoparticles. Food Sci Nutr 2024; 12:3725-3734. [PMID: 38726453 PMCID: PMC11077205 DOI: 10.1002/fsn3.4043] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/05/2023] [Revised: 01/23/2024] [Accepted: 02/04/2024] [Indexed: 05/12/2024] Open
Abstract
Toxoplasma gondii is a highly prevalent pathogen, reported from almost all geographical regions of the world. Current anti-T. gondii drugs are not effective enough in immunocompromised patients, encephalitis, chorioretinitis, and congenital toxoplasmosis. Therefore, the prescription of these drugs has been limited. Rose hip oil (RhO) is a natural plant compound, which shows antibacterial, anticancer, and anti-inflammatory activities. In the current study, the anti-T. gondii and cell toxicity effects of solid lipid nanoparticles (SLNs) loaded by RhO (RhO-SLNs) were evaluated. Emulsification sonicated-homogenization method was used to prepare SLNs. RhO-SLNs were characterized, and their anti-T. gondii and cell toxicity effects were evaluated using in vitro analyses. The particle size and the zeta potential of the nanoparticles were 152.09 nm and -15.3 mV nm, respectively. The entrapment efficiency percentage was 79.1%. In the present study, the inhibitory concentration (IC)50 against T. gondii was >1 μg/mL (p-value <.0001). The cell toxicity assay showed cytotoxicity concentration (CC)50 >10 mg/mL (p-value = .017). In addition, at least 75% of T. gondii-infected Vero cells remained alive at concentrations >10 mg/mL. The concentration of 1 mg/mL showed highest anti-Toxoplasma activity and lowest cell toxicity against the Vero cell. Our findings suggest that carrying natural plant compounds with SLNs could be considered an effective option for treatment strategies against T. gondii infections.
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Affiliation(s)
- Hanieh Mohammad Rahimi
- Foodborne and Waterborne Diseases Research CenterResearch Institute for Gastroenterology and Liver Diseases, Shahid Beheshti University of Medical SciencesTehranIran
| | - Zahra Hesari
- Department of PharmaceuticsSchool of Pharmacy, Guilan University of Medical SciencesRashtIran
| | - Elnaz Sadat Mirsamadi
- Department of Microbiology, Faculty of MedicineTehran Medical Sciences, Islamic Azad UniversityTehranIran
| | - Sara Nemati
- Foodborne and Waterborne Diseases Research CenterResearch Institute for Gastroenterology and Liver Diseases, Shahid Beheshti University of Medical SciencesTehranIran
| | - Hamed Mirjalali
- Foodborne and Waterborne Diseases Research CenterResearch Institute for Gastroenterology and Liver Diseases, Shahid Beheshti University of Medical SciencesTehranIran
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2
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Tajeri S, Chattopadhyay D, Langsley G, Nijhof AM. A Theileria annulata parasite with a single mutation, methionine 128 to isoleucine (M128I), in cytochrome B is resistant to buparvaquone. PLoS One 2024; 19:e0299002. [PMID: 38626086 PMCID: PMC11020719 DOI: 10.1371/journal.pone.0299002] [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: 11/13/2023] [Accepted: 02/04/2024] [Indexed: 04/18/2024] Open
Abstract
Tropical theileriosis is a fatal leukemic-like disease of cattle caused by the tick-transmitted protozoan parasite Theileria annulata. The economics of cattle meat and milk production is severely affected by theileriosis in endemic areas. The hydroxynaphtoquinone buparvaquone (BPQ) is the only available drug currently used to treat clinical theileriosis, whilst BPQ resistance is emerging and spreading in endemic areas. Here, we chronically exposed T. annulata-transformed macrophages in vitro to BPQ and monitored the emergence of drug-resistant parasites. Surviving parasites revealed a significant increase in BPQ IC50 compared to the wild type parasites. Drug resistant parasites from two independent cloned lines had an identical single mutation, M128I, in the gene coding for T. annulata cytochrome B (Tacytb). This in vitro generated mutation has not been reported in resistant field isolates previously, but is reminiscent of the methionine to isoleucine mutation in atovaquone-resistant Plasmodium and Babesia. The M128I mutation did not appear to exert any deleterious effect on parasite fitness (proliferation and differentiation to merozoites). To gain insight into whether drug-resistance could have resulted from altered drug binding to TaCytB we generated in silico a 3D-model of wild type TaCytB and docked BPQ to the predicted 3D-structure. Potential binding sites cluster in four areas of the protein structure including the Q01 site. The bound drug in the Q01 site is expected to pack against an alpha helix, which included M128, suggesting that the change in amino acid in this position may alter drug-binding. The in vitro generated BPQ resistant T. annulata is a useful tool to determine the contribution of the various predicted docking sites to BPQ resistance and will also allow testing novel drugs against theileriosis for their potential to overcome BPQ resistance.
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Affiliation(s)
- Shahin Tajeri
- Institute for Parasitology and Tropical Veterinary Medicine, Freie Universität Berlin, Berlin, Germany
- Veterinary Centre for Resistance Research, Freie Universität Berlin, Berlin, Germany
| | - Debasish Chattopadhyay
- Department of Medicine, University of Alabama at Birmingham, Birmingham, Alabama, United States of America
| | - Gordon Langsley
- Inserm U1016-CNRS UMR8104, Institut Cochin, Paris, France
- Laboratoire de Biologie Comparative des Apicomplexes, Faculté de Médecine, Université Paris Descartes—Sorbonne Paris Cité, Paris, France
| | - Ard M. Nijhof
- Institute for Parasitology and Tropical Veterinary Medicine, Freie Universität Berlin, Berlin, Germany
- Veterinary Centre for Resistance Research, Freie Universität Berlin, Berlin, Germany
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3
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Tetzlaff S, Hillebrand A, Drakoulis N, Gluhic Z, Maschmann S, Lyko P, Wicke S, Schmitz-Linneweber C. Small RNAs from mitochondrial genome recombination sites are incorporated into T. gondii mitoribosomes. eLife 2024; 13:e95407. [PMID: 38363119 PMCID: PMC10948144 DOI: 10.7554/elife.95407] [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: 12/29/2023] [Accepted: 01/23/2024] [Indexed: 02/17/2024] Open
Abstract
The mitochondrial genomes of apicomplexans comprise merely three protein-coding genes, alongside a set of thirty to forty genes encoding small RNAs (sRNAs), many of which exhibit homologies to rRNA from E. coli. The expression status and integration of these short RNAs into ribosomes remains unclear and direct evidence for active ribosomes within apicomplexan mitochondria is still lacking. In this study, we conducted small RNA sequencing on the apicomplexan Toxoplasma gondii to investigate the occurrence and function of mitochondrial sRNAs. To enhance the analysis of sRNA sequencing outcomes, we also re-sequenced the T. gondii mitochondrial genome using an improved organelle enrichment protocol and Nanopore sequencing. It has been established previously that the T. gondii genome comprises 21 sequence blocks that undergo recombination among themselves but that their order is not entirely random. The enhanced coverage of the mitochondrial genome allowed us to characterize block combinations at increased resolution. Employing this refined genome for sRNA mapping, we find that many small RNAs originated from the junction sites between protein-coding blocks and rRNA sequence blocks. Surprisingly, such block border sRNAs were incorporated into polysomes together with canonical rRNA fragments and mRNAs. In conclusion, apicomplexan ribosomes are active within polysomes and are indeed assembled through the integration of sRNAs, including previously undetected sRNAs with merged mRNA-rRNA sequences. Our findings lead to the hypothesis that T. gondii's block-based genome organization enables the dual utilization of mitochondrial sequences as both messenger RNAs and ribosomal RNAs, potentially establishing a link between the regulation of rRNA and mRNA expression.
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Affiliation(s)
| | | | | | - Zala Gluhic
- Molecular Genetics, Humboldt University BerlinBerlinGermany
| | | | - Peter Lyko
- Biodiversity and Evolution, Humboldt University BerlinBerlinGermany
| | - Susann Wicke
- Biodiversity and Evolution, Humboldt University BerlinBerlinGermany
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4
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Alfei S. Shifting from Ammonium to Phosphonium Salts: A Promising Strategy to Develop Next-Generation Weapons against Biofilms. Pharmaceutics 2024; 16:80. [PMID: 38258091 PMCID: PMC10819902 DOI: 10.3390/pharmaceutics16010080] [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: 11/24/2023] [Revised: 01/03/2024] [Accepted: 01/04/2024] [Indexed: 01/24/2024] Open
Abstract
Since they are difficult and sometimes impossible to treat, infections sustained by multidrug-resistant (MDR) pathogens, emerging especially in nosocomial environments, are an increasing global public health concern, translating into high mortality and healthcare costs. In addition to having acquired intrinsic abilities to resist available antibiotic treatments, MDR bacteria can transmit genetic material encoding for resistance to non-mutated bacteria, thus strongly decreasing the number of available effective antibiotics. Moreover, several pathogens develop resistance by forming biofilms (BFs), a safe and antibiotic-resistant home for microorganisms. BFs are made of well-organized bacterial communities, encased and protected in a self-produced extracellular polymeric matrix, which impedes antibiotics' ability to reach bacteria, thus causing them to lose efficacy. By adhering to living or abiotic surfaces in healthcare settings, especially in intensive care units where immunocompromised older patients with several comorbidities are hospitalized BFs cause the onset of difficult-to-eradicate infections. In this context, recent studies have demonstrated that quaternary ammonium compounds (QACs), acting as membrane disruptors and initially with a low tendency to develop resistance, have demonstrated anti-BF potentialities. However, a paucity of innovation in this space has driven the emergence of QAC resistance. More recently, quaternary phosphonium salts (QPSs), including tri-phenyl alkyl phosphonium derivatives, achievable by easy one-step reactions and well known as intermediates of the Wittig reaction, have shown promising anti-BF effects in vitro. Here, after an overview of pathogen resistance, BFs, and QACs, we have reviewed the QPSs developed and assayed to this end, so far. Finally, the synthetic strategies used to prepare QPSs have also been provided and discussed to spur the synthesis of novel compounds of this class. We think that the extension of the knowledge about these materials by this review could be a successful approach to finding effective weapons for treating chronic infections and device-associated diseases sustained by BF-producing MDR bacteria.
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Affiliation(s)
- Silvana Alfei
- Department of Pharmacy, University of Genoa, Viale Cembrano, 4, 16148 Genova, Italy
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5
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Rodriguez JB, Szajnman SH. An updated review of chemical compounds with anti-Toxoplasma gondii activity. Eur J Med Chem 2023; 262:115885. [PMID: 37871407 DOI: 10.1016/j.ejmech.2023.115885] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/24/2023] [Revised: 09/30/2023] [Accepted: 10/15/2023] [Indexed: 10/25/2023]
Abstract
The opportunistic apicomplexan parasite Toxoplasma gondii is the etiologic agent for toxoplasmosis, which can infect a widespread range of hosts, particularly humans and warm-blooded animals. The present chemotherapy to treat or prevent toxoplasmosis is deficient and is based on diverse drugs such as atovaquone, trimethoprim, spiramycine, which are effective in acute toxoplasmosis. Therefore, a safe chemotherapy is required for toxoplasmosis considering that its responsible agent, T. gondii, provokes severe illness and death in pregnant women and immunodeficient patients. A certain disadvantage of the available treatments is the lack of effectiveness against the tissue cyst of the parasite. A safe chemotherapy to combat toxoplasmosis should be based on the metabolic differences between the parasite and the mammalian host. This article covers different relevant molecular targets to combat this disease including the isoprenoid pathway (farnesyl diphosphate synthase, squalene synthase), dihydrofolate reductase, calcium-dependent protein kinases, histone deacetylase, mitochondrial electron transport chain, etc.
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Affiliation(s)
- Juan B Rodriguez
- Departamento de Química Orgánica, Facultad de Ciencias Exactas y Naturales, Universidad de Buenos Aires, Ciudad Universitaria, Pabellón 2, C1428EHA, Buenos Aires, Argentina; CONICET-Universidad de Buenos Aires, Unidad de Microanálisis y Métodos Físicos en Química Orgánica (UMYMFOR), C1428EHA, Buenos Aires, Argentina.
| | - Sergio H Szajnman
- Departamento de Química Orgánica, Facultad de Ciencias Exactas y Naturales, Universidad de Buenos Aires, Ciudad Universitaria, Pabellón 2, C1428EHA, Buenos Aires, Argentina; CONICET-Universidad de Buenos Aires, Unidad de Microanálisis y Métodos Físicos en Química Orgánica (UMYMFOR), C1428EHA, Buenos Aires, Argentina
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6
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Lamb IM, Okoye IC, Mather MW, Vaidya AB. Unique Properties of Apicomplexan Mitochondria. Annu Rev Microbiol 2023; 77:541-560. [PMID: 37406344 DOI: 10.1146/annurev-micro-032421-120540] [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] [Indexed: 07/07/2023]
Abstract
Apicomplexan parasites constitute more than 6,000 species infecting a wide range of hosts. These include important pathogens such as those causing malaria and toxoplasmosis. Their evolutionary emergence coincided with the dawn of animals. Mitochondrial genomes of apicomplexan parasites have undergone dramatic reduction in their coding capacity, with genes for only three proteins and ribosomal RNA genes present in scrambled fragments originating from both strands. Different branches of the apicomplexans have undergone rearrangements of these genes, with Toxoplasma having massive variations in gene arrangements spread over multiple copies. The vast evolutionary distance between the parasite and the host mitochondria has been exploited for the development of antiparasitic drugs, especially those used to treat malaria, wherein inhibition of the parasite mitochondrial respiratory chain is selectively targeted with little toxicity to the host mitochondria. We describe additional unique characteristics of the parasite mitochondria that are being investigated and provide greater insights into these deep-branching eukaryotic pathogens.
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Affiliation(s)
- Ian M Lamb
- Center for Molecular Parasitology, Department of Microbiology and Immunology, Drexel University College of Medicine, Philadelphia, Pennsylvania, USA;
| | - Ijeoma C Okoye
- Center for Molecular Parasitology, Department of Microbiology and Immunology, Drexel University College of Medicine, Philadelphia, Pennsylvania, USA;
| | - Michael W Mather
- Center for Molecular Parasitology, Department of Microbiology and Immunology, Drexel University College of Medicine, Philadelphia, Pennsylvania, USA;
| | - Akhil B Vaidya
- Center for Molecular Parasitology, Department of Microbiology and Immunology, Drexel University College of Medicine, Philadelphia, Pennsylvania, USA;
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7
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Hayward JA, Makota FV, Cihalova D, Leonard RA, Rajendran E, Zwahlen SM, Shuttleworth L, Wiedemann U, Spry C, Saliba KJ, Maier AG, van Dooren GG. A screen of drug-like molecules identifies chemically diverse electron transport chain inhibitors in apicomplexan parasites. PLoS Pathog 2023; 19:e1011517. [PMID: 37471441 PMCID: PMC10403144 DOI: 10.1371/journal.ppat.1011517] [Citation(s) in RCA: 2] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/18/2022] [Revised: 08/04/2023] [Accepted: 06/28/2023] [Indexed: 07/22/2023] Open
Abstract
Apicomplexans are widespread parasites of humans and other animals, and include the causative agents of malaria (Plasmodium species) and toxoplasmosis (Toxoplasma gondii). Existing anti-apicomplexan therapies are beset with issues around drug resistance and toxicity, and new treatment options are needed. The mitochondrial electron transport chain (ETC) is one of the few processes that has been validated as a drug target in apicomplexans. To identify new inhibitors of the apicomplexan ETC, we developed a Seahorse XFe96 flux analyzer approach to screen the 400 compounds contained within the Medicines for Malaria Venture 'Pathogen Box' for ETC inhibition. We identified six chemically diverse, on-target inhibitors of the ETC in T. gondii, at least four of which also target the ETC of Plasmodium falciparum. Two of the identified compounds (MMV024937 and MMV688853) represent novel ETC inhibitor chemotypes. MMV688853 belongs to a compound class, the aminopyrazole carboxamides, that were shown previously to target a kinase with a key role in parasite invasion of host cells. Our data therefore reveal that MMV688853 has dual targets in apicomplexans. We further developed our approach to pinpoint the molecular targets of these inhibitors, demonstrating that all target Complex III of the ETC, with MMV688853 targeting the ubiquinone reduction (Qi) site of the complex. Most of the compounds we identified remain effective inhibitors of parasites that are resistant to Complex III inhibitors that are in clinical use or development, indicating that they could be used in treating drug resistant parasites. In sum, we have developed a versatile, scalable approach to screen for compounds that target the ETC in apicomplexan parasites, and used this to identify and characterize novel inhibitors.
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Affiliation(s)
- Jenni A. Hayward
- Research School of Biology, Australian National University, Canberra, Australia
| | - F. Victor Makota
- Research School of Biology, Australian National University, Canberra, Australia
| | - Daniela Cihalova
- Research School of Biology, Australian National University, Canberra, Australia
| | - Rachel A. Leonard
- Research School of Biology, Australian National University, Canberra, Australia
| | - Esther Rajendran
- Research School of Biology, Australian National University, Canberra, Australia
| | - Soraya M. Zwahlen
- Research School of Biology, Australian National University, Canberra, Australia
| | - Laura Shuttleworth
- Research School of Biology, Australian National University, Canberra, Australia
| | - Ursula Wiedemann
- Research School of Biology, Australian National University, Canberra, Australia
| | - Christina Spry
- Research School of Biology, Australian National University, Canberra, Australia
| | - Kevin J. Saliba
- Research School of Biology, Australian National University, Canberra, Australia
| | - Alexander G. Maier
- Research School of Biology, Australian National University, Canberra, Australia
| | - Giel G. van Dooren
- Research School of Biology, Australian National University, Canberra, Australia
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8
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Eid RK, Arafa MF, Ashour DS, Essa EA, El-Wakil ES, Younis SS, El Maghraby GM. Surfactant vesicles for enhanced antitoxoplasmic effect of norfloxacin: in vitro and in vivo evaluations. Int J Pharm 2023; 638:122912. [PMID: 37015296 DOI: 10.1016/j.ijpharm.2023.122912] [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: 02/02/2023] [Revised: 03/27/2023] [Accepted: 03/29/2023] [Indexed: 04/06/2023]
Abstract
The goal was to scrutinize niosomes as potential carriers for enhanced efficacy of norfloxacin against Toxoplasma gondii RH strain. This was assessed in vitro and in vivo. Standard niosomes of Span 60 and cholesterol were prepared. Gelucire 48/16 or Tween 80 was incorporated as hydrophilic fluidizer. The prepared vesicles were characterized for shape, size, viscosity and norfloxacin release. The in vitro anti-Toxoplasma was assessed by monitoring tachyzoites viability after incubation with niosomes. In vivo efficacy of niosomes encapsulated norfloxacin was evaluated on infected mice. Transmission electron micrographs showed nano-sized spherical vesicles. Norfloxacin release varied with niosomal composition to show faster liberation in presence of fluidizing agent. The half maximum effective concentration of norfloxacin against tachyzoites (EC50) was significantly reduced after niosomal encapsulation compared with simple drug solution with no significant difference between vesicular formulations. Tachyzoite count in the peritoneal fluid of infected mice was reduced by 45.2, 90.8, 88.3 and 84% after treatment with simple drug dispersion, standard niosomes, Gelucire containing and Tween containing vesicles, respectively compared to infected untreated mice. These results correlate with the in vitro data and reflects the efficacy of niosomes. The study introduced surfactant vesicles as a tool for enhanced efficacy of norfloxacin against toxoplasma.
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Affiliation(s)
- Rania K Eid
- Department of Pharmaceutical Technology, Faculty of Pharmacy, Tanta University, Tanta, Egypt.
| | - Mona F Arafa
- Department of Pharmaceutical Technology, Faculty of Pharmacy, Tanta University, Tanta, Egypt.
| | - Dalia S Ashour
- Department of Parasitology, Faculty of Medicine, Tanta University, Tanta, Egypt.
| | - Ebtessam A Essa
- Department of Pharmaceutical Technology, Faculty of Pharmacy, Tanta University, Tanta, Egypt.
| | - Eman S El-Wakil
- Department of Parasitology, Theodor Bilharz Research Institute, Kornaish El-Nile, Warrak El-Hadar, Imbaba (P.O. 30), Giza, 12411, Egypt.
| | - Salwa S Younis
- Medical Parasitology Department, Faculty of Medicine, Alexandria University, Egypt.
| | - Gamal M El Maghraby
- Department of Pharmaceutical Technology, Faculty of Pharmacy, Tanta University, Tanta, Egypt.
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Maclean AE, Hayward JA, Huet D, van Dooren GG, Sheiner L. The mystery of massive mitochondrial complexes: the apicomplexan respiratory chain. Trends Parasitol 2022; 38:1041-1052. [PMID: 36302692 PMCID: PMC10434753 DOI: 10.1016/j.pt.2022.09.008] [Citation(s) in RCA: 8] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/06/2022] [Revised: 09/21/2022] [Accepted: 09/23/2022] [Indexed: 11/05/2022]
Abstract
The mitochondrial respiratory chain is an essential pathway in most studied eukaryotes due to its roles in respiration and other pathways that depend on mitochondrial membrane potential. Apicomplexans are unicellular eukaryotes whose members have an impact on global health. The respiratory chain is a drug target for some members of this group, notably the malaria-causing Plasmodium spp. This has motivated studies of the respiratory chain in apicomplexan parasites, primarily Toxoplasma gondii and Plasmodium spp. for which experimental tools are most advanced. Studies of the respiratory complexes in these organisms revealed numerous novel features, including expansion of complex size. The divergence of apicomplexan mitochondria from commonly studied models highlights the diversity of mitochondrial form and function across eukaryotic life.
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Affiliation(s)
- Andrew E Maclean
- Wellcome Centre for Integrative Parasitology, University of Glasgow, Glasgow, UK
| | - Jenni A Hayward
- Research School of Biology, Australian National University, Canberra, Australia
| | - Diego Huet
- Center for Tropical & Emerging Diseases, University of Georgia, Athens, GA, USA; Department of Pharmaceutical and Biomedical Sciences, University of Georgia, Athens, GA, USA
| | - Giel G van Dooren
- Research School of Biology, Australian National University, Canberra, Australia
| | - Lilach Sheiner
- Wellcome Centre for Integrative Parasitology, University of Glasgow, Glasgow, UK.
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10
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Multiple point mutations in cytochrome b gene of Babesia gibsoni – A possible cause for buparvaquone resistance. Vet Parasitol 2022; 312:109823. [DOI: 10.1016/j.vetpar.2022.109823] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/20/2022] [Revised: 10/13/2022] [Accepted: 10/17/2022] [Indexed: 11/29/2022]
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11
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Ali Q, Zahid O, Mhadhbi M, Jones B, Darghouth MA, Raynes G, Afshan K, Birtles R, Sargison ND, Betson M, Chaudhry U. Genetic characterisation of the Theileria annulata cytochrome b locus and its impact on buparvaquone resistance in bovine. Int J Parasitol Drugs Drug Resist 2022; 20:65-75. [PMID: 36183440 PMCID: PMC9529669 DOI: 10.1016/j.ijpddr.2022.08.004] [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: 07/11/2022] [Revised: 08/11/2022] [Accepted: 08/21/2022] [Indexed: 12/14/2022]
Abstract
Control of tropical theileriosis, caused by the apicomplexan Theileria annulata, depends on the use of a single drug, buparvaquone, the efficacy of which is compromised by the emergence of resistance. The present study was undertaken to improve understanding of the role of mutations conferring buparvaquone resistance in T. annulata, and the effects of selection pressures on their emergence and spread. First, we investigated genetic characteristics of the cytochrome b locus associated with buparvaquone resistance in 10 susceptible and 7 resistant T. annulata isolates. The 129G (GGC) mutation was found in the Q01 binding pocket and 253S (TCT) and 262S (TCA) mutations were identified within the Q02 binding pocket. Next, we examined field isolates and identified cytochrome b mutations 129G (GGC), 253S (TCT) and 262S (TCA) in 21/75 buffalo-derived and 19/119 cattle-derived T. annulata isolates, providing evidence of positive selection pressure. Both hard and soft selective sweeps were identified, with striking differences between isolates. For example, 19 buffalo-derived and 7 cattle-derived isolates contained 129G (GGC) and 253S (TCT) resistance haplotypes at a high frequency, implying the emergence of resistance by a single mutation. Two buffalo-derived and 12 cattle-derived isolates contained equally high frequencies of 129G (GGC), 253S (TCT), 129G (GGC)/253S (TCT) and 262S (TCA) resistance haplotypes, implying the emergence of resistance by pre-existing or recurrent mutations. Phylogenetic analysis further revealed that 9 and 21 unique haplotypes in buffalo and cattle-derived isolates were present in a single lineage, suggesting a single origin. We propose that animal migration between farms is an important factor in the spread of buparvaquone resistance in endemic regions of Pakistan. The overall outcomes will be useful in understanding how drug resistance emerges and spreads, and this information will help design strategies to optimise the use and lifespan of the single most drug use to control tropical theileriosis.
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Affiliation(s)
- Qasim Ali
- Faculty of Veterinary and Animal Sciences, University of Agriculture, Dera Ismail Khan, Pakistan
| | - Osama Zahid
- Royal (Dick) School of Veterinary Studies, University of Edinburgh, UK
| | - Moez Mhadhbi
- Laboratoire de Parasitologie, École Nationale de Médecine Vétérinaire, Université de La Manouba, Sidi Thabet, Tunisia
| | - Ben Jones
- School of Veterinary Medicine, University of Surrey, UK
| | - Mohamed Aziz Darghouth
- Laboratoire de Parasitologie, École Nationale de Médecine Vétérinaire, Université de La Manouba, Sidi Thabet, Tunisia
| | - George Raynes
- Royal (Dick) School of Veterinary Studies, University of Edinburgh, UK
| | - Kiran Afshan
- Department of Zoology, Faculty of Biological Sciences, Quaid-i-Azam University, Islamabad, Pakistan
| | - Richard Birtles
- School of Science, Engineering and Environment, University of Salford, UK
| | - Neil D. Sargison
- Royal (Dick) School of Veterinary Studies, University of Edinburgh, UK
| | - Martha Betson
- School of Veterinary Medicine, University of Surrey, UK
| | - Umer Chaudhry
- School of Veterinary Medicine, University of Surrey, UK,Corresponding author. School of Veterinary Medicine, University of Surrey, GU2 7AL, UK.
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12
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Zhang H, Yan X, Zhang Y, Bao C, Li C. An oxygen-economical nano-photosensitizer with a high photodynamic therapeutic outcome via simultaneous reduction of the cellular respiration and oxygen depletion of PDT. J Mater Chem B 2022; 10:4623-4631. [PMID: 35647782 DOI: 10.1039/d2tb00309k] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
Abstract
The development of photodynamic nanomedicines that can alleviate intratumoral oxygen deficiency during photodynamic therapy (PDT) is of great significance for improving the therapeutic outcome of solid tumors characterized by severe hypoxia. Massive oxygen consumption due to vigorous cellular respiration, i.e., mitochondrial-associated oxidative phosphorylation (OXPHOS), is another major cause of severe tumor hypoxia in addition to insufficient oxygen supply. Moreover, oxygen depletion during PDT further exacerbates the shortage of intratumoral oxygen. In this work, we engineered a novel oxygen-economical nano-photosensitizer via co-encapsulation of an OXPHOS inhibitor (ATO) and a newly developed type-I photosensitizer (IPS) into a polymeric micelle of PEG-b-PCL. By controlling the length of hydrophobic PCL segments, we successfully optimized the micelle size to around 30 nm for enhanced tumor penetration. The orchestration of the two functional components, ATO and IPS, can simultaneously hinder the two major tumor oxygen-consuming pathways, where ATO targets mitochondrial complex III to inhibit cellular respiration, while IPS generates ROS through a low oxygen-consuming type-I photochemical pathway, enabling remarkable PDT efficacies in both hypoxic cells and a 4T1 tumor-bearing BALB/c mouse model. This work sheds new light on the construction of nano-photosensitizers to rejuvenate PDT against hypoxic solid tumors.
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Affiliation(s)
- Hao Zhang
- School of Material Science and Engineering, Tiangong University, No. 399 BinShuiXi Road, Tianjin 300387, China.
| | - Xiaosa Yan
- State Key Laboratory of Medicinal Chemical Biology, Nankai University, Tianjin 300071, China.
| | - Yongkang Zhang
- State Key Laboratory of Medicinal Chemical Biology, Nankai University, Tianjin 300071, China.
| | - Chenlu Bao
- School of Material Science and Engineering, Tiangong University, No. 399 BinShuiXi Road, Tianjin 300387, China.
| | - Changhua Li
- State Key Laboratory of Medicinal Chemical Biology, Nankai University, Tianjin 300071, China.
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13
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Bicyclic azetidines target acute and chronic stages of Toxoplasma gondii by inhibiting parasite phenylalanyl t-RNA synthetase. Nat Commun 2022; 13:459. [PMID: 35075105 PMCID: PMC8786932 DOI: 10.1038/s41467-022-28108-y] [Citation(s) in RCA: 7] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/03/2021] [Accepted: 01/10/2022] [Indexed: 11/24/2022] Open
Abstract
Toxoplasma gondii commonly infects humans and while most infections are controlled by the immune response, currently approved drugs are not capable of clearing chronic infection in humans. Hence, approximately one third of the world’s human population is at risk of reactivation, potentially leading to severe sequelae. To identify new candidates for treating chronic infection, we investigated a series of compounds derived from diversity-oriented synthesis. Bicyclic azetidines are potent low nanomolar inhibitors of phenylalanine tRNA synthetase (PheRS) in T. gondii, with excellent selectivity. Biochemical and genetic studies validate PheRS as the primary target of bicyclic azetidines in T. gondii, providing a structural basis for rational design of improved analogs. Favorable pharmacokinetic properties of a lead compound provide excellent protection from acute infection and partial protection from chronic infection in an immunocompromised mouse model of toxoplasmosis. Collectively, PheRS inhibitors of the bicyclic azetidine series offer promise for treatment of chronic toxoplasmosis. Current treatments for toxoplasmosis are limited by adverse reactions and inability to cure chronic infections dominated by semi-dormant cyst forms. Here the authors demonstrate the potential of small molecule inhibitors of PheRS for controlling acute and chronic toxoplasmosis.
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14
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Multidrug resistance crisis during COVID-19 pandemic: Role of anti-microbial peptides as next-generation therapeutics. Colloids Surf B Biointerfaces 2021; 211:112303. [PMID: 34952285 PMCID: PMC8685351 DOI: 10.1016/j.colsurfb.2021.112303] [Citation(s) in RCA: 16] [Impact Index Per Article: 5.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/26/2021] [Revised: 12/03/2021] [Accepted: 12/16/2021] [Indexed: 02/07/2023]
Abstract
The decreasing effectiveness of conventional drugs due to multidrug-resistance is a major challenge for the scientific community, necessitating development of novel antimicrobial agents. In the present era of coronavirus 2 (COVID-19) pandemic, patients are being widely exposed to antimicrobial drugs and hence the problem of multidrug-resistance shall be aggravated in the days to come. Consequently, revisiting the phenomena of multidrug resistance leading to formulation of effective antimicrobial agents is the need of the hour. As a result, this review sheds light on the looming crisis of multidrug resistance in wake of the COVID-19 pandemic. It highlights the problem, significance and approaches for tackling microbial resistance with special emphasis on anti-microbial peptides as next-generation therapeutics against multidrug resistance associated diseases. Antimicrobial peptides exhibit exceptional mechanism of action enabling rapid killing of microbes at low concentration, antibiofilm activity, immunomodulatory properties along with a low tendency for resistance development providing them an edge over conventional antibiotics. The review is unique as it discusses the mode of action, pharmacodynamic properties and application of antimicrobial peptides in areas ranging from therapeutics to agriculture.
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15
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Elmehankar MS, Elhenawy AA, Aboukamar WA, Elzoheiry MA, Nabih N. Histopathological and ultrastructural assessment of atovaquone-proguanil hydrochloride combination in chronic murine toxoplasmosis. Ultrastruct Pathol 2021; 45:376-383. [PMID: 34595988 DOI: 10.1080/01913123.2021.1984349] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/20/2022]
Abstract
Over one billion people worldwide are expected to have Toxoplasma gondii infection with anonymous health problems. Available therapies are ineffective for persistent chronic toxoplasmosis. So, there is an imperative need for effective therapies to eliminate chronic tissue stage. In this study, we aimed to assess the effect of a drug combination of atovaquone and proguanil hydrochloride in the treatment of experimental chronic toxoplasmosis. Fifty Swiss Webster mice were used in the study. Forty mice were infected with Me49 type II cystogenic Toxoplasma gondii strain and allocated into four groups: infected untreated (vehicle-administered), infected and treated with cotrimoxazole (CTX) 370 mg/kg/day, infected and treated with atovaquone (ATV) 100 mg/kg/day, and infected and treated with atovaquone/proguanil (ATV/PROG) 50 mg/kg/day. An additional group of uninfected mice was used as an uninfected control group. Drug treatment was initiated 8 weeks post-infection and continued for two weeks. All mice were sacrificed 12 weeks post-infection. Parasitological and histopathological parameters were assessed. Toxoplasma gondii cysts recovered from brain tissue homogenates of both infected untreated and ATV/PROG-treated groups were examined by scanning electron microscopy. Combined ATV/PROG treatment demonstrated a significant reduction of Toxoplasma gondii cyst count in brain tissue (a reduction rate of 84.87%) compared to untreated group (P < .001). Brain tissues obtained from ATV/PROG treated group showed reduction of inflammatory infiltrate and marked attenuation and deformation of recovered Toxoplasma gondii cysts. We conclude that ATV/PROG drug combination could offer a potential drug therapy for Toxoplasma gondii chronic cystic stage.
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Affiliation(s)
- Manar S Elmehankar
- Department of Medical Parasitology, Faculty of Medicine, Mansoura University, Mansoura, Egypt
| | - Abeer A Elhenawy
- Department of Medical Parasitology, Faculty of Medicine, Mansoura University, Mansoura, Egypt
| | - Wafaa A Aboukamar
- Department of Medical Parasitology, Faculty of Medicine, Mansoura University, Mansoura, Egypt
| | - Manal A Elzoheiry
- Department of Medical Parasitology, Faculty of Medicine, Mansoura University, Mansoura, Egypt
| | - Nairmen Nabih
- Department of Medical Parasitology, Faculty of Medicine, Mansoura University, Mansoura, Egypt
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16
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da Silva M, Teixeira C, Gomes P, Borges M. Promising Drug Targets and Compounds with Anti- Toxoplasma gondii Activity. Microorganisms 2021; 9:1960. [PMID: 34576854 PMCID: PMC8471693 DOI: 10.3390/microorganisms9091960] [Citation(s) in RCA: 15] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/29/2021] [Revised: 09/09/2021] [Accepted: 09/10/2021] [Indexed: 12/25/2022] Open
Abstract
Toxoplasmosis is a parasitic disease caused by the globally distributed protozoan parasite Toxoplasma gondii, which infects around one-third of the world population. This disease may result in serious complications for fetuses, newborns, and immunocompromised individuals. Current treatment options are old, limited, and possess toxic side effects. Long treatment durations are required since the current therapeutic system lacks efficiency against T. gondii tissue cysts, promoting the establishment of latent infection. This review highlights the most promising drug targets involved in anti-T. gondii drug discovery, including the mitochondrial electron transport chain, microneme secretion pathway, type II fatty acid synthesis, DNA synthesis and replication and, DNA expression as well as others. A description of some of the most promising compounds demonstrating antiparasitic activity, developed over the last decade through drug discovery and drug repurposing, is provided as a means of giving new perspectives for future research in this field.
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Affiliation(s)
- Marco da Silva
- Departamento de Ciências Biológicas, Faculdade de Farmácia da Universidade do Porto, 4050-313 Porto, Portugal;
| | - Cátia Teixeira
- LAQV-REQUIMTE, Departamento de Química e Bioquímica, Faculdade de Ciências da Universidade do Porto, 4169-007 Porto, Portugal; (C.T.); (P.G.)
| | - Paula Gomes
- LAQV-REQUIMTE, Departamento de Química e Bioquímica, Faculdade de Ciências da Universidade do Porto, 4169-007 Porto, Portugal; (C.T.); (P.G.)
| | - Margarida Borges
- Associate Laboratory i4HB—Institute for Health and Bioeconomy, Faculty of Pharmacy, University of Porto, 4050-313 Porto, Portugal
- UCIBIO/REQUIMTE, Laboratory of Toxicology, Department of Biological Sciences, Faculty of Pharmacy, University of Porto, 4050-313 Porto, Portugal
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17
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Alomar ML, Yañuk JG, Angel SO, Gonzalez MM, Cabrerizo FM. In vitro Effect of Harmine Alkaloid and Its N-Methyl Derivatives Against Toxoplasma gondii. Front Microbiol 2021; 12:716534. [PMID: 34421876 PMCID: PMC8375385 DOI: 10.3389/fmicb.2021.716534] [Citation(s) in RCA: 6] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/28/2021] [Accepted: 07/07/2021] [Indexed: 11/22/2022] Open
Abstract
Toxoplasmosis is one of the most prevalent and neglected zoonotic global diseases caused by Toxoplasma gondii. The current pharmacological treatments show clinical limitations, and therefore, the search for new drugs is an urgent need in order to eradicate this infection. Due to their intrinsic biological activities, β-carboline (βC) alkaloids might represent a good alternative that deserves further investigations. In this context, the in vitro anti-T. gondii activity of three βCs, harmine (1), 2-methyl-harminium (2), and 9-methyl-harmine (3), was evaluated herein. Briefly, the three alkaloids exerted direct effects on the parasite invasion and/or replication capability. Replication rates of intracellular treated tachyzoites were also affected in a dose-dependent manner, at noncytotoxic concentrations for host cells. Additionally, cell cycle analysis revealed that both methyl-derivatives 2 and 3 induce parasite arrest in S/M phases. Compound 3 showed the highest irreversible parasite growth inhibition, with a half maximal inhibitory concentration (IC50) value of 1.8 ± 0.2 μM and a selectivity index (SI) of 17.2 at 4 days post infection. Due to high replication rates, tachyzoites are frequently subjected to DNA double-strand breaks (DSBs). This highly toxic lesion triggers a series of DNA damage response reactions, starting with a kinase cascade that phosphorylates a large number of substrates, including the histone H2A.X to lead the early DSB marker γH2A.X. Western blot studies showed that basal expression of γH2A.X was reduced in the presence of 3. Interestingly, the typical increase in γH2A.X levels produced by camptothecin (CPT), a drug that generates DSB, was not observed when CPT was co-administered with 3. These findings suggest that 3 might disrupt Toxoplasma DNA damage response.
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Affiliation(s)
- Maria L Alomar
- Laboratorio de Fotoquímica y Fotobiología Molecular, Instituto Tecnológico de Chascomús (INTECH), Universidad Nacional de San Martín (UNSAM) - Consejo Nacional de Investigaciones Científicas y Técnicas (CONICET), Chascomús, Argentina
| | - Juan G Yañuk
- Laboratorio de Fotoquímica y Fotobiología Molecular, Instituto Tecnológico de Chascomús (INTECH), Universidad Nacional de San Martín (UNSAM) - Consejo Nacional de Investigaciones Científicas y Técnicas (CONICET), Chascomús, Argentina
| | - Sergio O Angel
- Laboratorio de Parasitología Molecular, INTECH, UNSAM - CONICET, Chascomús, Argentina
| | - M Micaela Gonzalez
- Laboratorio de Fotoquímica y Fotobiología Molecular, Instituto Tecnológico de Chascomús (INTECH), Universidad Nacional de San Martín (UNSAM) - Consejo Nacional de Investigaciones Científicas y Técnicas (CONICET), Chascomús, Argentina
| | - Franco M Cabrerizo
- Laboratorio de Fotoquímica y Fotobiología Molecular, Instituto Tecnológico de Chascomús (INTECH), Universidad Nacional de San Martín (UNSAM) - Consejo Nacional de Investigaciones Científicas y Técnicas (CONICET), Chascomús, Argentina
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18
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Namasivayam S, Baptista RP, Xiao W, Hall EM, Doggett JS, Troell K, Kissinger JC. A novel fragmented mitochondrial genome in the protist pathogen Toxoplasma gondii and related tissue coccidia. Genome Res 2021; 31:852-865. [PMID: 33906963 PMCID: PMC8092004 DOI: 10.1101/gr.266403.120] [Citation(s) in RCA: 9] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/24/2020] [Accepted: 03/09/2021] [Indexed: 12/19/2022]
Abstract
Mitochondrial genome content and structure vary widely across the eukaryotic tree of life, with protists displaying extreme examples. Apicomplexan and dinoflagellate protists have evolved highly reduced mitochondrial genome sequences, mtDNA, consisting of only three cytochrome genes and fragmented rRNA genes. Here, we report the independent evolution of fragmented cytochrome genes in Toxoplasma and related tissue coccidia and evolution of a novel genome architecture consisting minimally of 21 sequence blocks (SBs) totaling 5.9 kb that exist as nonrandom concatemers. Single-molecule Nanopore reads consisting entirely of SBs ranging from 0.1 to 23.6 kb reveal both whole and fragmented cytochrome genes. Full-length cytochrome transcripts including a divergent coxIII are detected. The topology of the mitochondrial genome remains an enigma. Analysis of a cob point mutation reveals that homoplasmy of SBs is maintained. Tissue coccidia are important pathogens of man and animals, and the mitochondrion represents an important therapeutic target. The mtDNA sequence has been elucidated, but a definitive genome architecture remains elusive.
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Affiliation(s)
- Sivaranjani Namasivayam
- Department of Genetics, University of Georgia, Athens, Georgia 30602, USA.,Center for Tropical and Emerging Global Diseases, University of Georgia, Athens, Georgia 30602, USA
| | - Rodrigo P Baptista
- Center for Tropical and Emerging Global Diseases, University of Georgia, Athens, Georgia 30602, USA.,Institute of Bioinformatics, University of Georgia, Athens, Georgia 30602, USA
| | - Wenyuan Xiao
- Department of Genetics, University of Georgia, Athens, Georgia 30602, USA.,Center for Tropical and Emerging Global Diseases, University of Georgia, Athens, Georgia 30602, USA
| | - Erica M Hall
- Department of Genetics, University of Georgia, Athens, Georgia 30602, USA
| | - Joseph S Doggett
- Division of Infectious Diseases, Oregon Health Sciences University, Portland, Oregon 97239, USA.,Division of Infectious Diseases, Veterans Affairs Portland Health Care System, Portland, Oregon 97239, USA
| | - Karin Troell
- Department of Microbiology, National Veterinary Institute, SE-751 89 Uppsala, Sweden
| | - Jessica C Kissinger
- Department of Genetics, University of Georgia, Athens, Georgia 30602, USA.,Center for Tropical and Emerging Global Diseases, University of Georgia, Athens, Georgia 30602, USA.,Institute of Bioinformatics, University of Georgia, Athens, Georgia 30602, USA
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19
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Ma CI, Tirtorahardjo JA, Jan S, Schweizer SS, Rosario SAC, Du Y, Zhang JJ, Morrissette NS, Andrade RM. Auranofin Resistance in Toxoplasma gondii Decreases the Accumulation of Reactive Oxygen Species but Does Not Target Parasite Thioredoxin Reductase. Front Cell Infect Microbiol 2021; 11:618994. [PMID: 33816332 PMCID: PMC8017268 DOI: 10.3389/fcimb.2021.618994] [Citation(s) in RCA: 7] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/19/2020] [Accepted: 01/07/2021] [Indexed: 12/12/2022] Open
Abstract
Auranofin, a reprofiled FDA-approved drug originally designed to treat rheumatoid arthritis, has emerged as a promising anti-parasitic drug. It induces the accumulation of reactive oxygen species (ROS) in parasites, including Toxoplasma gondii. We generated auranofin resistant T. gondii lines through chemical mutagenesis to identify the molecular target of this drug. Resistant clones were confirmed with a competition assay using wild-type T. gondii expressing yellow fluorescence protein (YFP) as a reference strain. The predicted auranofin target, thioredoxin reductase, was not mutated in any of our resistant lines. Subsequent whole genomic sequencing analysis (WGS) did not reveal a consensus resistance locus, although many have point mutations in genes encoding redox-relevant proteins such as superoxide dismutase (TgSOD2) and ribonucleotide reductase. We investigated the SOD2 L201P mutation and found that it was not sufficient to confer resistance when introduced into wild-type parasites. Resistant clones accumulated less ROS than their wild type counterparts. Our results demonstrate that resistance to auranofin in T. gondii enhances its ability to abate oxidative stress through diverse mechanisms. This evidence supports a hypothesized mechanism of auranofin anti-parasitic activity as disruption of redox homeostasis.
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Affiliation(s)
- Christopher I. Ma
- Division of Infectious Diseases, Department of Medicine, University of California Irvine, Irvine, CA, United States
| | - James A. Tirtorahardjo
- Department of Microbiology and Molecular Genetics, University of California Irvine, Irvine, CA, United States
| | - Sharon Jan
- Department of Microbiology and Molecular Genetics, University of California Irvine, Irvine, CA, United States
| | - Sakura S. Schweizer
- Division of Infectious Diseases, Department of Medicine, University of California Irvine, Irvine, CA, United States
- School of Biological Sciences, University of California Irvine, Irvine, CA, United States
| | - Shawn A. C. Rosario
- School of Biological Sciences, University of California Irvine, Irvine, CA, United States
| | - Yanmiao Du
- School of Biological Sciences, University of California Irvine, Irvine, CA, United States
| | - Jerry J. Zhang
- Division of Infectious Diseases, Department of Medicine, University of California Irvine, Irvine, CA, United States
| | - Naomi S. Morrissette
- Department of Molecular Biology and Biochemistry, University of California Irvine, Irvine, CA, United States
| | - Rosa M. Andrade
- Division of Infectious Diseases, Department of Medicine, University of California Irvine, Irvine, CA, United States
- Department of Microbiology and Molecular Genetics, University of California Irvine, Irvine, CA, United States
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20
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Elsheikha HM, Marra CM, Zhu XQ. Epidemiology, Pathophysiology, Diagnosis, and Management of Cerebral Toxoplasmosis. Clin Microbiol Rev 2021; 34:e00115-19. [PMID: 33239310 PMCID: PMC7690944 DOI: 10.1128/cmr.00115-19] [Citation(s) in RCA: 70] [Impact Index Per Article: 23.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/06/2023] Open
Abstract
Toxoplasma gondii is known to infect a considerable number of mammalian and avian species and a substantial proportion of the world's human population. The parasite has an impressive ability to disseminate within the host's body and employs various tactics to overcome the highly regulatory blood-brain barrier and reside in the brain. In healthy individuals, T. gondii infection is largely tolerated without any obvious ill effects. However, primary infection in immunosuppressed patients can result in acute cerebral or systemic disease, and reactivation of latent tissue cysts can lead to a deadly outcome. It is imperative that treatment of life-threatening toxoplasmic encephalitis is timely and effective. Several therapeutic and prophylactic regimens have been used in clinical practice. Current approaches can control infection caused by the invasive and highly proliferative tachyzoites but cannot eliminate the dormant tissue cysts. Adverse events and other limitations are associated with the standard pyrimethamine-based therapy, and effective vaccines are unavailable. In this review, the epidemiology, economic impact, pathophysiology, diagnosis, and management of cerebral toxoplasmosis are discussed, and critical areas for future research are highlighted.
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Affiliation(s)
- Hany M Elsheikha
- Faculty of Medicine and Health Sciences, School of Veterinary Medicine and Science, University of Nottingham, Loughborough, United Kingdom
| | - Christina M Marra
- Departments of Neurology and Medicine, University of Washington School of Medicine, Seattle, Washington, USA
| | - Xing-Quan Zhu
- State Key Laboratory of Veterinary Etiological Biology, Key Laboratory of Veterinary Parasitology of Gansu Province, Lanzhou Veterinary Research Institute, Chinese Academy of Agricultural Sciences, Lanzhou, Gansu Province, People's Republic of China
- College of Veterinary Medicine, Shanxi Agricultural University, Taigu, Shanxi Province, People's Republic of China
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21
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Hayward JA, Rajendran E, Zwahlen SM, Faou P, van Dooren GG. Divergent features of the coenzyme Q:cytochrome c oxidoreductase complex in Toxoplasma gondii parasites. PLoS Pathog 2021; 17:e1009211. [PMID: 33524071 PMCID: PMC7877769 DOI: 10.1371/journal.ppat.1009211] [Citation(s) in RCA: 15] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/19/2020] [Revised: 02/11/2021] [Accepted: 12/03/2020] [Indexed: 11/19/2022] Open
Abstract
The mitochondrion is critical for the survival of apicomplexan parasites. Several major anti-parasitic drugs, such as atovaquone and endochin-like quinolones, act through inhibition of the mitochondrial electron transport chain at the coenzyme Q:cytochrome c oxidoreductase complex (Complex III). Despite being an important drug target, the protein composition of Complex III of apicomplexan parasites has not been elucidated. Here, we undertake a mass spectrometry-based proteomic analysis of Complex III in the apicomplexan Toxoplasma gondii. Along with canonical subunits that are conserved across eukaryotic evolution, we identify several novel or highly divergent Complex III components that are conserved within the apicomplexan lineage. We demonstrate that one such subunit, which we term TgQCR11, is critical for parasite proliferation, mitochondrial oxygen consumption and Complex III activity, and establish that loss of this protein leads to defects in Complex III integrity. We conclude that the protein composition of Complex III in apicomplexans differs from that of the mammalian hosts that these parasites infect.
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Affiliation(s)
- Jenni A. Hayward
- Research School of Biology, Australian National University, Canberra, Australia
| | - Esther Rajendran
- Research School of Biology, Australian National University, Canberra, Australia
| | - Soraya M. Zwahlen
- Research School of Biology, Australian National University, Canberra, Australia
| | - Pierre Faou
- Department of Biochemistry and Genetics, La Trobe Institute for Molecular Science, La Trobe University, Melbourne, Australia
| | - Giel G. van Dooren
- Research School of Biology, Australian National University, Canberra, Australia
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22
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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: 78] [Impact Index Per Article: 19.5] [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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23
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El-Shafey AAM, Hegab MHA, Seliem MME, Barakat AMA, Mostafa NE, Abdel-Maksoud HA, Abdelhameed RM. Curcumin@metal organic frameworks nano-composite for treatment of chronic toxoplasmosis. JOURNAL OF MATERIALS SCIENCE. MATERIALS IN MEDICINE 2020; 31:90. [PMID: 33089411 DOI: 10.1007/s10856-020-06429-y] [Citation(s) in RCA: 18] [Impact Index Per Article: 4.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/04/2019] [Accepted: 09/24/2020] [Indexed: 06/11/2023]
Abstract
Toxoplasmosis is a zoonotic protozoal disease caused by Toxoplasma gondii, an intracellular opportunistic protozoan parasite that can infect any warm-blooded vertebrate cell. In this study, zirconium, and iron-based metal-organic framework was prepared according to the solvothermal method. New nanocomposite (Curcumin@MOFs) was prepared by reacting curcumin with amino-functionalized metal-organic frameworks (Fe-MOF and UiO-66-NH2). Besides characterizations of the composite by powder X-ray diffraction and scanning electron microscope, nano-Curcumin@MOFs was used as a new novel structure as atrial for treatment of chronic toxoplasmosis. Results showed a reduced number of brain cysts, high levels of serum Toxo IgG, and normal histo-morphology with preserved parenchymal, and stromal tissues in rats groups treated with curcumin and Curcumin@MOFs nanocomposite.
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Affiliation(s)
| | - Mohammed H A Hegab
- Medical Parasitology Department, Faculty of Medicine, Zagazig University, Zagazig, Egypt
| | | | - Ashraf M A Barakat
- Zoonotic Diseases Department, National Research Centre, 33 Bohouth str. Dokki, Giza, Egypt
| | - Nahed E Mostafa
- Medical Parasitology Department, Faculty of Medicine, Zagazig University, Zagazig, Egypt
| | - Hanem A Abdel-Maksoud
- Medical Parasitology Department, Faculty of Medicine, Zagazig University, Zagazig, Egypt
| | - Reda M Abdelhameed
- Applied Organic Chemistry Department, Chemical Industries Research Division, National Research Centre, 33 Bohouth str. Dokki, Giza, Egypt.
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24
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Orally Bioavailable Endochin-Like Quinolone Carbonate Ester Prodrug Reduces Toxoplasma gondii Brain Cysts. Antimicrob Agents Chemother 2020; 64:AAC.00535-20. [PMID: 32540978 DOI: 10.1128/aac.00535-20] [Citation(s) in RCA: 11] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/19/2020] [Accepted: 06/03/2020] [Indexed: 11/20/2022] Open
Abstract
Toxoplasmosis is a potentially fatal infection for immunocompromised people and the developing fetus. Current medicines for toxoplasmosis have high rates of adverse effects that interfere with therapeutic and prophylactic regimens. Endochin-like quinolones (ELQs) are potent inhibitors of Toxoplasma gondii proliferation in vitro and in animal models of acute and latent infection. ELQ-316, in particular, was found to be effective orally against acute toxoplasmosis in mice and highly selective for T. gondii cytochrome b over human cytochrome b Despite its oral efficacy, the high crystallinity of ELQ-316 limits oral absorption, plasma concentrations, and therapeutic potential. A carbonate ester prodrug of ELQ-316, ELQ-334, was created to decrease crystallinity and increase oral bioavailability, which resulted in a 6-fold increase in both the maximum plasma concentration (C max) and the area under the curve (AUC) of ELQ-316. The increased bioavailability of ELQ-316, when administered as ELQ-334, resulted in efficacy against acute toxoplasmosis greater than that of an equivalent dose of ELQ-316 and had efficacy against latent toxoplasmosis similar to that of ELQ-316 administered intraperitoneally. Treatment with carbonate ester prodrugs is a successful strategy to overcome the limited oral bioavailability of ELQs for the treatment of toxoplasmosis.
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Hatton O, Stitzlein L, Dudley RW, Charvat RA. Evaluating the Antiparasitic Activity of Novel BPZ Derivatives Against Toxoplasma gondii. Microorganisms 2020; 8:microorganisms8081159. [PMID: 32751616 PMCID: PMC7466062 DOI: 10.3390/microorganisms8081159] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/30/2020] [Revised: 07/26/2020] [Accepted: 07/27/2020] [Indexed: 11/16/2022] Open
Abstract
Prevalence studies revealed that one-third of the human population is chronically infected with Toxoplasma gondii. Presently, such infections are without medical treatment that effectively eradicates the parasite once it is in its latent form. Moreover, the therapeutics used to treat acute infections are poorly tolerated by patients and also cause the parasite to convert into long-lasting tissue cysts. Hence, there is a dire need for compounds with antiparasitic activity against all forms of T. gondii. This study examines the antiparasitic capacity of nine novel bisphenol Z (BPZ) derivatives to determine whether they possessed any activity that prevented T. gondii replication. To begin assessing the efficacy of the novel derivatives, parasites were treated with increasing concentrations of the compounds, then doubling assays and MitoTracker staining were performed. Three of the nine compounds demonstrated strong inhibitory activity, i.e., parasite replication significantly decreased with higher concentrations. Additionally, many of the treated parasites exhibited decreases in fluorescent signaling and disruption of mitochondrial morphology. These findings suggest that bisphenol Z compounds disrupt mitochondrial function to inhibit parasite replication and may provide a foundation for the development of new and effective treatment modalities against T. gondii.
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Affiliation(s)
- Olivia Hatton
- Department of Biology, University of Findlay, Findlay, OH 45840, USA;
| | - Lea Stitzlein
- College of Pharmacy, University of Findlay, Findlay, OH 45840, USA; (L.S.); (R.W.D.)
| | - Richard W. Dudley
- College of Pharmacy, University of Findlay, Findlay, OH 45840, USA; (L.S.); (R.W.D.)
| | - Robert A. Charvat
- Department of Biology, University of Findlay, Findlay, OH 45840, USA;
- Correspondence: ; Tel.: +1-419-434-5746
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Hines SA, Brandvold J, Mealey RH, Call DR, Graça T. Exposure to ambient air causes degradation and decreased in vitro potency of buparvaquone and parvaquone. Vet Parasitol 2020; 277S:100023. [PMID: 32904749 PMCID: PMC7458381 DOI: 10.1016/j.vpoa.2020.100023] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/31/2019] [Revised: 02/04/2020] [Accepted: 02/05/2020] [Indexed: 02/04/2023]
Abstract
Buparvaquone and parvaquone are used to treat livestock infected with Theileria spp. Air exposure had a significant impact on the stability of buparvaquone and parvaquone. Parvaquone was more stable than buparvaquone. Drug degradation was related with loss of potency by an in vitro viability assay.
Buparvaquone and parvaquone are hydroxynaphthoquinone compounds commonly used to treat livestock infected with Theileria species such as T. parva and T. annulata. In many (sub)tropical regions, chromatic changes in medicines can result from extreme environmental conditions and improper drug storage or handling, raising the possibility of drug degradation and loss of potency. We evaluated the effects of UV light, elevated temperature, and atmospheric air on the stability and potency of both buparvaquone and parvaquone by using a combination of high performance liquid chromatography (HPLC) and a T. equi based in vitro parasite growth inhibition assay (to measure potency). Aliquots (1 ml; 3 replicates per treatment) of each compound were subjected to a variety of treatments that varied in duration and intensity followed by HPLC and potency assays. Exposure to ambient air for 50 days was correlated with a significant loss of potency for both buparvaquone (4535%, P < 0.05) and parvaquone (247%, P < 0.05), while elevated temperature (37°C) and UV light exposure (24 h) had no significant impact (P > 0.05). The decrease in potency of both buparvaquone and parvaquone correlated with drug degradation (r = -0.74 and -0.88, respectively) as measured by HPLC. In practice, if there is headspace present in the vial, then ambient air will invariably enter the vial and contribute to degradation of these compounds. Such degradation may contribute to increasing drug resistance, economic losses for farmers, and animal welfare concerns for animals that are treated for Theileria infections.
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Affiliation(s)
- Siddra A Hines
- Department of Veterinary Microbiology and Pathology, Pullman, WA 99164-7090, USA
| | - Jacob Brandvold
- Paul G. Allen School for Global Animal Health, Washington State University, Pullman, WA 99164-7090, USA
| | - Robert H Mealey
- Department of Veterinary Microbiology and Pathology, Pullman, WA 99164-7090, USA
| | - Douglas R Call
- Department of Veterinary Microbiology and Pathology, Pullman, WA 99164-7090, USA; Paul G. Allen School for Global Animal Health, Washington State University, Pullman, WA 99164-7090, USA
| | - Telmo Graça
- Paul G. Allen School for Global Animal Health, Washington State University, Pullman, WA 99164-7090, USA.
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Verdaguer IB, Zafra CA, Crispim M, Sussmann RA, Kimura EA, Katzin AM. Prenylquinones in Human Parasitic Protozoa: Biosynthesis, Physiological Functions, and Potential as Chemotherapeutic Targets. Molecules 2019; 24:molecules24203721. [PMID: 31623105 PMCID: PMC6832408 DOI: 10.3390/molecules24203721] [Citation(s) in RCA: 8] [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: 08/05/2019] [Revised: 09/25/2019] [Accepted: 10/01/2019] [Indexed: 12/19/2022] Open
Abstract
Human parasitic protozoa cause a large number of diseases worldwide and, for some of these diseases, there are no effective treatments to date, and drug resistance has been observed. For these reasons, the discovery of new etiological treatments is necessary. In this sense, parasitic metabolic pathways that are absent in vertebrate hosts would be interesting research candidates for the identification of new drug targets. Most likely due to the protozoa variability, uncertain phylogenetic origin, endosymbiotic events, and evolutionary pressure for adaptation to adverse environments, a surprising variety of prenylquinones can be found within these organisms. These compounds are involved in essential metabolic reactions in organisms, for example, prevention of lipoperoxidation, participation in the mitochondrial respiratory chain or as enzymatic cofactors. This review will describe several prenylquinones that have been previously characterized in human pathogenic protozoa. Among all existing prenylquinones, this review is focused on ubiquinone, menaquinone, tocopherols, chlorobiumquinone, and thermoplasmaquinone. This review will also discuss the biosynthesis of prenylquinones, starting from the isoprenic side chains to the aromatic head group precursors. The isoprenic side chain biosynthesis maybe come from mevalonate or non-mevalonate pathways as well as leucine dependent pathways for isoprenoid biosynthesis. Finally, the isoprenic chains elongation and prenylquinone aromatic precursors origins from amino acid degradation or the shikimate pathway is reviewed. The phylogenetic distribution and what is known about the biological functions of these compounds among species will be described, as will the therapeutic strategies associated with prenylquinone metabolism in protozoan parasites.
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Affiliation(s)
- Ignasi B. Verdaguer
- Department of Parasitology, Institute of Biomedical Sciences, University of São Paulo, São Paulo 05508000, Brazil; (I.B.V.); (C.A.Z.); (M.C.); (E.A.K.)
| | - Camila A. Zafra
- Department of Parasitology, Institute of Biomedical Sciences, University of São Paulo, São Paulo 05508000, Brazil; (I.B.V.); (C.A.Z.); (M.C.); (E.A.K.)
| | - Marcell Crispim
- Department of Parasitology, Institute of Biomedical Sciences, University of São Paulo, São Paulo 05508000, Brazil; (I.B.V.); (C.A.Z.); (M.C.); (E.A.K.)
| | - Rodrigo A.C. Sussmann
- Department of Parasitology, Institute of Biomedical Sciences, University of São Paulo, São Paulo 05508000, Brazil; (I.B.V.); (C.A.Z.); (M.C.); (E.A.K.)
- Centro de Formação em Ciências Ambientais, Universidade Federal do Sul da Bahia, Porto Seguro 45810-000 Bahia, Brazil
| | - Emília A. Kimura
- Department of Parasitology, Institute of Biomedical Sciences, University of São Paulo, São Paulo 05508000, Brazil; (I.B.V.); (C.A.Z.); (M.C.); (E.A.K.)
| | - Alejandro M. Katzin
- Department of Parasitology, Institute of Biomedical Sciences, University of São Paulo, São Paulo 05508000, Brazil; (I.B.V.); (C.A.Z.); (M.C.); (E.A.K.)
- Correspondence: ; Tel.: +55-11-3091-7330; Fax: +5511-3091-7417
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Barrett MP, Kyle DE, Sibley LD, Radke JB, Tarleton RL. Protozoan persister-like cells and drug treatment failure. Nat Rev Microbiol 2019; 17:607-620. [PMID: 31444481 PMCID: PMC7024564 DOI: 10.1038/s41579-019-0238-x] [Citation(s) in RCA: 77] [Impact Index Per Article: 15.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 07/03/2019] [Indexed: 01/01/2023]
Abstract
Antimicrobial treatment failure threatens our ability to control infections. In addition to antimicrobial resistance, treatment failures are increasingly understood to derive from cells that survive drug treatment without selection of genetically heritable mutations. Parasitic protozoa, such as Plasmodium species that cause malaria, Toxoplasma gondii and kinetoplastid protozoa, including Trypanosoma cruzi and Leishmania spp., cause millions of deaths globally. These organisms can evolve drug resistance and they also exhibit phenotypic diversity, including the formation of quiescent or dormant forms that contribute to the establishment of long-term infections that are refractory to drug treatment, which we refer to as 'persister-like cells'. In this Review, we discuss protozoan persister-like cells that have been linked to persistent infections and discuss their impact on therapeutic outcomes following drug treatment.
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Affiliation(s)
- Michael P Barrett
- Wellcome Centre for Integrative Parasitology, Institute of Infection, Immunity and Inflammation, University of Glasgow, Glasgow, UK.
| | - Dennis E Kyle
- Center for Tropical and Emerging Global Diseases, University of Georgia, Athens, GA, USA
| | - L David Sibley
- Department of Molecular Microbiology, Washington University School of Medicine, St Louis, MO, USA
| | - Joshua B Radke
- Department of Molecular Microbiology, Washington University School of Medicine, St Louis, MO, USA
| | - Rick L Tarleton
- Center for Tropical and Emerging Global Diseases, University of Georgia, Athens, GA, USA
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Same same, but different: Uncovering unique features of the mitochondrial respiratory chain of apicomplexans. Mol Biochem Parasitol 2019; 232:111204. [DOI: 10.1016/j.molbiopara.2019.111204] [Citation(s) in RCA: 21] [Impact Index Per Article: 4.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/02/2019] [Revised: 07/19/2019] [Accepted: 08/01/2019] [Indexed: 01/08/2023]
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30
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Simon MS, Westblade LF, Dziedziech A, Visone JE, Furman RR, Jenkins SG, Schuetz AN, Kirkman LA. Clinical and Molecular Evidence of Atovaquone and Azithromycin Resistance in Relapsed Babesia microti Infection Associated With Rituximab and Chronic Lymphocytic Leukemia. Clin Infect Dis 2019; 65:1222-1225. [PMID: 28541469 DOI: 10.1093/cid/cix477] [Citation(s) in RCA: 46] [Impact Index Per Article: 9.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/07/2017] [Accepted: 05/22/2017] [Indexed: 11/15/2022] Open
Abstract
Babesiosis treatment failures with standard therapy have been reported, but the molecular mechanisms are not well understood. We describe the emergence of atovaquone and azithromycin resistance associated with mutations in the binding regions of the target proteins of both drugs during treatment of an immunosuppressed patient with relapsing babesiosis.
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Affiliation(s)
| | | | | | | | - Richard R Furman
- Department of Medicine, Division of Hematology Oncology, Weill Cornell Medicine,New York, New York; and
| | | | - Audrey N Schuetz
- Mayo Clinic, Department of Laboratory Medicine and Pathology, Rochester, Minnesota
| | - Laura A Kirkman
- Department of Medicine, Division of Infectious Diseases
- Department of Microbiology and Immunology, and
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31
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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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32
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Sánchez-Sánchez R, Vázquez P, Ferre I, Ortega-Mora LM. Treatment of Toxoplasmosis and Neosporosis in Farm Ruminants: State of Knowledge and Future Trends. Curr Top Med Chem 2019; 18:1304-1323. [PMID: 30277158 PMCID: PMC6340160 DOI: 10.2174/1568026618666181002113617] [Citation(s) in RCA: 30] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/01/2018] [Revised: 08/03/2018] [Accepted: 09/13/2018] [Indexed: 12/17/2022]
Abstract
Toxoplasmosis and neosporosis are closely related protozoan diseases that lead to important economic impacts in farm ruminants. Toxoplasma gondii infection mainly causes reproductive failure in small ruminants and is a widespread zoonosis, whereas Neospora caninum infection is one of the most important causes of abortion in cattle worldwide. Vaccination has been considered the most economic measure for controlling these diseases. However, despite vaccine development efforts, only a live-attenuated T. gondii vaccine has been licensed for veterinary use, and no promising vaccines against ne-osporosis have been developed; therefore, vaccine development remains a key goal. Additionally, drug therapy could be a valuable strategy for disease control in farm ruminants, as several drugs that limit T. gondii and N. caninum proliferation and dissemination have been evaluated. This approach may also be relevant to performing an initial drug screening for potential human therapy for zoonotic parasites. Treat-ments can be applied against infections in adult ruminants to minimize the outcomes of a primo-infection or the reactivation of a chronic infection during gestation or in newborn ruminants to avoid infection chronification. In this review, the current status of drug development against toxoplasmosis and neosporo-sis in farm ruminants is presented, and in an effort to promote additional treatment options, prospective drugs that have shown efficacy in vitro and in laboratory animal models of toxoplasmosis and neosporosis are examined
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Affiliation(s)
- Roberto Sánchez-Sánchez
- SALUVET, Animal Health Department, Faculty of Veterinary Sciences, Complutense University of Madrid, Ciudad Universitaria s/n, 28040, Madrid, Spain
| | - Patricia Vázquez
- SALUVET, Animal Health Department, Faculty of Veterinary Sciences, Complutense University of Madrid, Ciudad Universitaria s/n, 28040, Madrid, Spain
| | - Ignacio Ferre
- SALUVET, Animal Health Department, Faculty of Veterinary Sciences, Complutense University of Madrid, Ciudad Universitaria s/n, 28040, Madrid, Spain
| | - Luis Miguel Ortega-Mora
- SALUVET, Animal Health Department, Faculty of Veterinary Sciences, Complutense University of Madrid, Ciudad Universitaria s/n, 28040, Madrid, Spain
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33
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Pramanik PK, Alam MN, Roy Chowdhury D, Chakraborti T. Drug Resistance in Protozoan Parasites: An Incessant Wrestle for Survival. J Glob Antimicrob Resist 2019; 18:1-11. [PMID: 30685461 DOI: 10.1016/j.jgar.2019.01.023] [Citation(s) in RCA: 26] [Impact Index Per Article: 5.2] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/30/2018] [Revised: 01/04/2019] [Accepted: 01/15/2019] [Indexed: 11/19/2022] Open
Abstract
Nowadays, drug resistance in parasites is considered to be one of the foremost concerns in health and disease management. It is interconnected worldwide and undermines the health of millions of people, threatening to grow worse. Unfortunately, it does not receive serious attention from every corner of society. Consequently, drug resistance in parasites is gradually complicating and challenging the treatment of parasitic diseases. In this context, we have dedicated ourselves to review the incidence of drug resistance in the protozoan parasites Plasmodium, Leishmania, Trypanosoma, Entamoeba and Toxoplasma gondii. Moreover, understanding the role of ATP-binding cassette (ABC) transporters in drug resistance is essential in the control of parasitic diseases. Therefore, we also focused on the involvement of ABC transporters in drug resistance, which will be a superior approach to find ways for better regulation of diseases caused by parasitic infections.
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Affiliation(s)
- Pijush Kanti Pramanik
- Department of Biochemistry and Biophysics, University of Kalyani, Kalyani 741235, West Bengal, India
| | - Md Nur Alam
- Department of Biochemistry and Biophysics, University of Kalyani, Kalyani 741235, West Bengal, India
| | - Dibyapriya Roy Chowdhury
- Department of Biochemistry and Biophysics, University of Kalyani, Kalyani 741235, West Bengal, India
| | - Tapati Chakraborti
- Department of Biochemistry and Biophysics, University of Kalyani, Kalyani 741235, West Bengal, India.
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34
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Vetrivel U, Nagarajan H. Deciphering ophthalmic adaptive inhibitors targeting RON4 of Toxoplasma gondii: An integrative in silico approach. Life Sci 2018; 213:82-93. [DOI: 10.1016/j.lfs.2018.10.022] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/21/2018] [Revised: 10/09/2018] [Accepted: 10/11/2018] [Indexed: 02/06/2023]
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35
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Montazeri M, Mehrzadi S, Sharif M, Sarvi S, Tanzifi A, Aghayan SA, Daryani A. Drug Resistance in Toxoplasma gondii. Front Microbiol 2018; 9:2587. [PMID: 30420849 PMCID: PMC6215853 DOI: 10.3389/fmicb.2018.02587] [Citation(s) in RCA: 102] [Impact Index Per Article: 17.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/30/2017] [Accepted: 10/10/2018] [Indexed: 12/12/2022] Open
Abstract
Toxoplasma gondii (T. gondii) is a global protozoan parasite infecting up to one-third of the world population. Pyrimethamine (PYR) and sulfadiazine (SDZ) are the most widely used drugs for treatment of toxoplasmosis; however, several failure cases have been recorded as well; suggesting the existence of drug resistant strains. This review aims to give a systematic and comprehensive understanding of drug resistance in T. gondii including mechanisms of resistance and sites of drug action in parasite. Analogous amino acid substitutions in the Toxoplasma enzyme were identified to confer PYR resistance. Moreover, resistance to clindamycin, spiramycin, and azithromycin is encoded in the rRNA genes of T. gondii. However, T. gondii SDZ resistance mechanism has not been proved yet. Recently there has been a slight increase in SDZ resistance. That is why the majority of studies were carried out using SDZ. Six strains resistant to SDZ were found in clinical cases between 2013 and 2017 which among Brazilian T. gondii isolates, TgCTBr11, Ck3, and Pg1 were identified in human toxoplasmosis, as well as in livestock intended for human consumption. In conclusion, recent experimental studies in clinical cases have clearly shown that drug resistance in Toxoplasma is ongoing. Thus, establishing a more effective therapeutic scheme in the treatment of toxoplasmosis is critically needed. The emergence of T. gondii strains resistant to current drugs, reviewed here, represents a concern not only for treatment failure but also for increased clinical severity in immunocompromised patients. To improve the therapeutic outcome in patients, a greater understanding of the exact mechanisms of drug resistance in T. gondii should be developed. Thus, monitoring the presence of resistant parasites, in food products, would seem a prudent public health program.
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Affiliation(s)
- Mahbobeh Montazeri
- Toxoplasmosis Research Center, Mazandaran University of Medical Sciences, Sari, Iran.,Student Research Committee, Mazandaran University of Medical Sciences, Sari, Iran
| | - Saeed Mehrzadi
- Razi Drug Research Center, Iran University of Medical Sciences, Tehran, Iran
| | - Mehdi Sharif
- Toxoplasmosis Research Center, Mazandaran University of Medical Sciences, Sari, Iran.,Department of Parasitology, School of Medicine, Sari Branch, Islamic Azad University, Sari, Iran
| | - Shahabeddin Sarvi
- Toxoplasmosis Research Center, Mazandaran University of Medical Sciences, Sari, Iran.,Department of Parasitology, Sari Medical School, Mazandaran University of Medical Sciences, Sari, Iran
| | - Asal Tanzifi
- Toxoplasmosis Research Center, Mazandaran University of Medical Sciences, Sari, Iran.,Student Research Committee, Mazandaran University of Medical Sciences, Sari, Iran
| | - Sargis A Aghayan
- Laboratory of Zoology, Research Institute of Biology, Yerevan State University, Yerevan, Armenia
| | - Ahmad Daryani
- Toxoplasmosis Research Center, Mazandaran University of Medical Sciences, Sari, Iran.,Department of Parasitology, Sari Medical School, Mazandaran University of Medical Sciences, Sari, Iran
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36
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Shukla A, Olszewski KL, Llinás M, Rommereim LM, Fox BA, Bzik DJ, Xia D, Wastling J, Beiting D, Roos DS, Shanmugam D. Glycolysis is important for optimal asexual growth and formation of mature tissue cysts by Toxoplasma gondii. Int J Parasitol 2018; 48:955-968. [PMID: 30176233 DOI: 10.1016/j.ijpara.2018.05.013] [Citation(s) in RCA: 31] [Impact Index Per Article: 5.2] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/20/2018] [Revised: 05/28/2018] [Accepted: 05/31/2018] [Indexed: 12/31/2022]
Abstract
Toxoplasma gondii can grow and replicate using either glucose or glutamine as the major carbon source. Here, we have studied the essentiality of glycolysis in the tachyzoite and bradyzoite stages of T. gondii, using transgenic parasites that lack a functional hexokinase gene (Δhk) in RH (Type-1) and Prugniaud (Type-II) strain parasites. Tachyzoite stage Δhk parasites exhibit a fitness defect similar to that reported previously for the major glucose transporter mutant, and remain virulent in mice. However, although Prugniaud strain Δhk tachyzoites were capable of transforming into bradyzoites in vitro, they were severely compromised in their ability to make mature bradyzoite cysts in the brain tissue of mice. Isotopic labelling studies reveal that glucose-deprived tacyzoites utilise glutamine to replenish glycolytic and pentose phosphate pathway intermediates via gluconeogenesis. Interestingly, while glutamine-deprived intracellular Δhk tachyzoites continued to replicate, extracellular parasites were unable to efficiently invade host cells. Further, studies on mutant tachyzoites lacking a functional phosphoenolpyruvate carboxykinase (Δpepck1) revealed that glutaminolysis is the sole source of gluconeogenic flux in glucose-deprived parasites. In addition, glutaminolysis is essential for sustaining oxidative phosphorylation in Δhk parasites, while wild type (wt) and Δpepck1 parasites can obtain ATP from either glycolysis or oxidative phosphorylation. This study provides insights into the role of nutrient metabolism during asexual propagation and development of T. gondii, and validates the versatile nature of central carbon and energy metabolism in this parasite.
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Affiliation(s)
- Anurag Shukla
- Biochemical Sciences Division, CSIR-National Chemical Laboratory, Pune, India
| | | | - Manuel Llinás
- Department of Biochemistry and Molecular Biology and Department of Chemistry, Huck Center for Malaria Research, The Pennsylvania State University, W126 Millennium Science Complex, University Park, PA, USA
| | - Leah M Rommereim
- Department of Microbiology and Immunology, Geisel School of Medicine at Dartmouth, Lebanon, NH, USA
| | - Barbara A Fox
- Department of Microbiology and Immunology, Geisel School of Medicine at Dartmouth, Lebanon, NH, USA
| | - David J Bzik
- Department of Microbiology and Immunology, Geisel School of Medicine at Dartmouth, Lebanon, NH, USA
| | - Dong Xia
- The Royal Veterinary College, London NW1 0TU, UK
| | - Jonathan Wastling
- Faculty of Natural Sciences, Keele University, Keele, Staffordshire, ST5 5BG, UK
| | - Daniel Beiting
- School of Veterinary Medicine, Dept. of Pathobiology, University of Pennsylvania, Philadelphia, PA, USA
| | - David S Roos
- Department of Biology and Penn Genome Frontiers Institute, University of Pennsylvania, Philadelphia, PA, USA.
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37
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Radke JB, Burrows JN, Goldberg DE, Sibley LD. Evaluation of Current and Emerging Antimalarial Medicines for Inhibition of Toxoplasma gondii Growth in Vitro. ACS Infect Dis 2018; 4:1264-1274. [PMID: 29998728 PMCID: PMC6093624 DOI: 10.1021/acsinfecdis.8b00113] [Citation(s) in RCA: 30] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/21/2022]
Abstract
Toxoplasma gondii is a common zoonotic infection of humans, and estimates indicate that 1-2 billion people are chronically infected. Although largely asymptomatic, chronic infection poses risk of serious disease due to reactivation should immunity decline. Current therapies for toxoplasmosis only control acute infection caused by actively proliferating tachyzoites but do not eradicate the chronic tissue cyst stages. As well, there are considerable adverse side effects of the most commonly used therapy of combined sulfadiazine and pyrimethamine. Targeting the folate pathway is also an effective treatment for malaria, caused by the related parasites Plasmodium spp., suggesting common agents might be used to treat both infections. Here, we evaluated currently approved and newly emerging medicines for malaria to determine if such compounds might also prove useful for treating toxoplasmosis. Surprisingly, the majority of antimalarial compounds being used currently or in development for treatment of malaria were only modestly effective at inhibiting in vitro growth of T. gondii tachyzoites. These findings suggest that many essential processes in P. falciparum that are targeted by antimalarial compounds are either divergent or nonessential in T. gondii, thus limiting options for repurposing of current antimalarial medicines for toxoplasmosis.
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Affiliation(s)
- Joshua B. Radke
- Department of Molecular Microbiology, Washington University Sch. Med., 600 S. Euclid Ave., St Louis, MO 63110
| | - Jeremy N. Burrows
- Medicines for Malaria Venture, ICC, Route de Pré3Bois 20, 1215 Geneva, Switzerland
| | - Daniel E. Goldberg
- Departments of Medicine and Molecular Microbiology, Washington University Sch. Med., 660 S. Euclid Ave., St Louis, MO 63110
| | - L. David Sibley
- Department of Molecular Microbiology, Washington University Sch. Med., 600 S. Euclid Ave., St Louis, MO 63110
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38
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Dard C, Marty P, Brenier-Pinchart MP, Garnaud C, Fricker-Hidalgo H, Pelloux H, Pomares C. Management of toxoplasmosis in transplant recipients: an update. Expert Rev Anti Infect Ther 2018; 16:447-460. [DOI: 10.1080/14787210.2018.1483721] [Citation(s) in RCA: 39] [Impact Index Per Article: 6.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/28/2022]
Affiliation(s)
- Céline Dard
- Laboratoire de Parasitologie-Mycologie, Centre Hospitalier Universitaire Grenoble Alpes, Grenoble Cedex France
- Institute for Advanced Biosciences (IAB), Team Host-Pathogen Interactions and Immunity to Infection, INSERM U1209 - CNRS UMR5309, Université Grenoble Alpes, Grenoble France
| | - Pierre Marty
- Faculté de Médecine, Laboratoire de Parasitologie-Mycologie, Centre Hospitalier Universitaire de Nice, 06202 Nice, France Université de la Côte d’Azur, Nice, France
- 38043, INSERM U1065, Centre Méditerranéen de Médecine Moléculaire, C3M, Nice, France
| | - Marie-Pierre Brenier-Pinchart
- Laboratoire de Parasitologie-Mycologie, Centre Hospitalier Universitaire Grenoble Alpes, Grenoble Cedex France
- Institute for Advanced Biosciences (IAB), Team Host-Pathogen Interactions and Immunity to Infection, INSERM U1209 - CNRS UMR5309, Université Grenoble Alpes, Grenoble France
| | - Cécile Garnaud
- Laboratoire de Parasitologie-Mycologie, Centre Hospitalier Universitaire Grenoble Alpes, Grenoble Cedex France
| | - Hélène Fricker-Hidalgo
- Laboratoire de Parasitologie-Mycologie, Centre Hospitalier Universitaire Grenoble Alpes, Grenoble Cedex France
| | - Hervé Pelloux
- Laboratoire de Parasitologie-Mycologie, Centre Hospitalier Universitaire Grenoble Alpes, Grenoble Cedex France
- Institute for Advanced Biosciences (IAB), Team Host-Pathogen Interactions and Immunity to Infection, INSERM U1209 - CNRS UMR5309, Université Grenoble Alpes, Grenoble France
| | - Christelle Pomares
- Faculté de Médecine, Laboratoire de Parasitologie-Mycologie, Centre Hospitalier Universitaire de Nice, 06202 Nice, France Université de la Côte d’Azur, Nice, France
- 38043, INSERM U1065, Centre Méditerranéen de Médecine Moléculaire, C3M, Nice, France
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39
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Salunke R, Mourier T, Banerjee M, Pain A, Shanmugam D. Highly diverged novel subunit composition of apicomplexan F-type ATP synthase identified from Toxoplasma gondii. PLoS Biol 2018; 16:e2006128. [PMID: 30005062 PMCID: PMC6059495 DOI: 10.1371/journal.pbio.2006128] [Citation(s) in RCA: 30] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/22/2018] [Revised: 07/25/2018] [Accepted: 06/22/2018] [Indexed: 12/18/2022] Open
Abstract
The mitochondrial F-type ATP synthase, a multisubunit nanomotor, is critical for maintaining cellular ATP levels. In T. gondii and other apicomplexan parasites, many subunit components necessary for proper assembly and functioning of this enzyme appear to be missing. Here, we report the identification of 20 novel subunits of T. gondii F-type ATP synthase from mass spectrometry analysis of partially purified monomeric (approximately 600 kDa) and dimeric (>1 MDa) forms of the enzyme. Despite extreme sequence diversification, key FO subunits a, b, and d can be identified from conserved structural features. Orthologs for these proteins are restricted to apicomplexan, chromerid, and dinoflagellate species. Interestingly, their absence in ciliates indicates a major diversion, with respect to subunit composition of this enzyme, within the alveolate clade. Discovery of these highly diversified novel components of the apicomplexan F-type ATP synthase complex could facilitate the development of novel antiparasitic agents. Structural and functional characterization of this unusual enzyme complex will advance our fundamental understanding of energy metabolism in apicomplexan species.
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Affiliation(s)
- Rahul Salunke
- Biochemical Sciences Division, CSIR-National Chemical Laboratory, Pune, Maharashtra, India
| | - Tobias Mourier
- Pathogen Genomics Laboratory, BESE Division, King Abdullah University of Science and Technology (KAUST), Thuwal, Saudi Arabia
| | - Manidipa Banerjee
- Kusuma School of Biological Sciences, Indian Institute of Technology-Delhi, Hauz Khas, New Delhi, India
| | - Arnab Pain
- Pathogen Genomics Laboratory, BESE Division, King Abdullah University of Science and Technology (KAUST), Thuwal, Saudi Arabia
| | - Dhanasekaran Shanmugam
- Biochemical Sciences Division, CSIR-National Chemical Laboratory, Pune, Maharashtra, India
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40
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Meier A, Erler H, Beitz E. Targeting Channels and Transporters in Protozoan Parasite Infections. Front Chem 2018; 6:88. [PMID: 29637069 PMCID: PMC5881087 DOI: 10.3389/fchem.2018.00088] [Citation(s) in RCA: 19] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/03/2018] [Accepted: 03/12/2018] [Indexed: 12/25/2022] Open
Abstract
Infectious diseases caused by pathogenic protozoa are among the most significant causes of death in humans. Therapeutic options are scarce and massively challenged by the emergence of resistant parasite strains. Many of the current anti-parasite drugs target soluble enzymes, generate unspecific oxidative stress, or act by an unresolved mechanism within the parasite. In recent years, collections of drug-like compounds derived from large-scale phenotypic screenings, such as the malaria or pathogen box, have been made available to researchers free of charge boosting the identification of novel promising targets. Remarkably, several of the compound hits have been found to inhibit membrane proteins at the periphery of the parasites, i.e., channels and transporters for ions and metabolites. In this review, we will focus on the progress made on targeting channels and transporters at different levels and the potential for use against infections with apicomplexan parasites mainly Plasmodium spp. (malaria) and Toxoplasma gondii (toxoplasmosis), with kinetoplastids Trypanosoma brucei (sleeping sickness), Trypanosoma cruzi (Chagas disease), and Leishmania ssp. (leishmaniasis), and the amoeba Entamoeba histolytica (amoebiasis).
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Affiliation(s)
- Anna Meier
- Department of Pharmaceutical and Medicinal Chemistry, Christian-Albrechts-University of Kiel, Kiel, Germany
| | - Holger Erler
- Department of Pharmaceutical and Medicinal Chemistry, Christian-Albrechts-University of Kiel, Kiel, Germany
| | - Eric Beitz
- Department of Pharmaceutical and Medicinal Chemistry, Christian-Albrechts-University of Kiel, Kiel, Germany
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41
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Song Z, Iorga BI, Mounkoro P, Fisher N, Meunier B. The antimalarial compound
ELQ
‐400 is an unusual inhibitor of the
bc
1
complex, targeting both
Q
o
and
Q
i
sites. FEBS Lett 2018; 592:1346-1356. [DOI: 10.1002/1873-3468.13035] [Citation(s) in RCA: 25] [Impact Index Per Article: 4.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/20/2018] [Revised: 03/07/2018] [Accepted: 03/08/2018] [Indexed: 11/08/2022]
Affiliation(s)
- Zehua Song
- Translational Research Institute Henan Provincial People's Hospital School of Medicine Henan University Zhengzhou China
- Institute for Integrative Biology of the Cell (I2BC) CEA CNRS Université Paris‐Sud Université Paris‐Saclay Gif‐sur‐Yvette France
| | - Bogdan I. Iorga
- Institut de Chimie des Substances Naturelles CNRS UPR 2301 Labex LERMIT Université Paris‐Saclay Gif‐sur‐Yvette France
| | - Pierre Mounkoro
- Institute for Integrative Biology of the Cell (I2BC) CEA CNRS Université Paris‐Sud Université Paris‐Saclay Gif‐sur‐Yvette France
| | - Nicholas Fisher
- MSU‐DOE Plant Research Laboratory Michigan State University East Lansing MI USA
| | - Brigitte Meunier
- Institute for Integrative Biology of the Cell (I2BC) CEA CNRS Université Paris‐Sud Université Paris‐Saclay Gif‐sur‐Yvette France
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42
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Amporndanai K, Johnson RM, O’Neill PM, Fishwick CWG, Jamson AH, Rawson S, Muench SP, Hasnain SS, Antonyuk SV. X-ray and cryo-EM structures of inhibitor-bound cytochrome bc1 complexes for structure-based drug discovery. IUCRJ 2018; 5:200-210. [PMID: 29765610 PMCID: PMC5947725 DOI: 10.1107/s2052252518001616] [Citation(s) in RCA: 15] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/04/2017] [Accepted: 01/26/2018] [Indexed: 05/10/2023]
Abstract
Cytochrome bc1, a dimeric multi-subunit electron-transport protein embedded in the inner mitochondrial membrane, is a major drug target for the treatment and prevention of malaria and toxoplasmosis. Structural studies of cytochrome bc1 from mammalian homologues co-crystallized with lead compounds have underpinned structure-based drug design to develop compounds with higher potency and selectivity. However, owing to the limited amount of cytochrome bc1 that may be available from parasites, all efforts have been focused on homologous cytochrome bc1 complexes from mammalian species, which has resulted in the failure of some drug candidates owing to toxicity in the host. Crystallographic studies of the native parasite proteins are not feasible owing to limited availability of the proteins. Here, it is demonstrated that cytochrome bc1 is highly amenable to single-particle cryo-EM (which uses significantly less protein) by solving the apo and two inhibitor-bound structures to ∼4.1 Å resolution, revealing clear inhibitor density at the binding site. Therefore, cryo-EM is proposed as a viable alternative method for structure-based drug discovery using both host and parasite enzymes.
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Affiliation(s)
- Kangsa Amporndanai
- Molecular Biophysics Group, Institute of Integrative Biology, Faculty of Health and Life Sciences, University of Liverpool, Liverpool L69 7ZB, England
| | - Rachel M. Johnson
- School of Biomedical Sciences, Faculty of Biological Sciences, University of Leeds, Leeds LS2 9JT, England
- Astbury Centre for Structural and Molecular Biology, University of Leeds, Leeds LS2 9JT, England
- School of Chemistry, University of Leeds, Leeds LS2 9JT, England
| | - Paul M. O’Neill
- Department of Chemistry, University of Liverpool, Liverpool L69 7ZD, England
| | - Colin W. G. Fishwick
- Astbury Centre for Structural and Molecular Biology, University of Leeds, Leeds LS2 9JT, England
- School of Chemistry, University of Leeds, Leeds LS2 9JT, England
| | - Alexander H. Jamson
- School of Biomedical Sciences, Faculty of Biological Sciences, University of Leeds, Leeds LS2 9JT, England
- Astbury Centre for Structural and Molecular Biology, University of Leeds, Leeds LS2 9JT, England
| | - Shaun Rawson
- School of Biomedical Sciences, Faculty of Biological Sciences, University of Leeds, Leeds LS2 9JT, England
- Astbury Centre for Structural and Molecular Biology, University of Leeds, Leeds LS2 9JT, England
| | - Stephen P. Muench
- School of Biomedical Sciences, Faculty of Biological Sciences, University of Leeds, Leeds LS2 9JT, England
- Astbury Centre for Structural and Molecular Biology, University of Leeds, Leeds LS2 9JT, England
| | - S. Samar Hasnain
- Molecular Biophysics Group, Institute of Integrative Biology, Faculty of Health and Life Sciences, University of Liverpool, Liverpool L69 7ZB, England
| | - Svetlana V. Antonyuk
- Molecular Biophysics Group, Institute of Integrative Biology, Faculty of Health and Life Sciences, University of Liverpool, Liverpool L69 7ZB, England
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43
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Lack of mitochondrial MutS homolog 1 in Toxoplasma gondii disrupts maintenance and fidelity of mitochondrial DNA and reveals metabolic plasticity. PLoS One 2017; 12:e0188040. [PMID: 29141004 PMCID: PMC5687708 DOI: 10.1371/journal.pone.0188040] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/16/2017] [Accepted: 10/31/2017] [Indexed: 11/19/2022] Open
Abstract
The importance of maintaining the fidelity of the mitochondrial genome is underscored by the presence of various repair pathways within this organelle. Presumably, the repair of mitochondrial DNA would be of particular importance in organisms that possess only a single mitochondrion, like the human pathogens Plasmodium falciparum and Toxoplasma gondii. Understanding the machinery that maintains mitochondrial DNA in these parasites is of particular relevance, as mitochondrial function is a validated and effective target for anti-parasitic drugs. We previously determined that the Toxoplasma MutS homolog TgMSH1 localizes to the mitochondrion. MutS homologs are key components of the nuclear mismatch repair system in mammalian cells, and both yeast and plants possess MutS homologs that localize to the mitochondria where they regulate DNA stability. Here we show that the lack of TgMSH1 results in accumulation of single nucleotide variations in mitochondrial DNA and a reduction in mitochondrial DNA content. Additionally, parasites lacking TgMSH1 function can survive treatment with the cytochrome b inhibitor atovaquone. While the Tgmsh1 knockout strain has several missense mutations in cytochrome b, none affect amino acids known to be determinants of atovaquone sensitivity and atovaquone is still able to inhibit electron transport in the Tgmsh1 mutants. Furthermore, culture of Tgmsh1 mutant in the presence atovaquone leads to parasites with enhanced atovaquone resistance and complete shutdown of respiration. Thus, parasites lacking TgMSH1 overcome the disruption of mitochondrial DNA by adapting their physiology allowing them to forgo the need for oxidative phosphorylation. Consistent with this idea, the Tgmsh1 mutant is resistant to mitochondrial inhibitors with diverse targets and exhibits reduced ability to grow in the absence of glucose. This work shows TgMSH1 as critical for the maintenance and fidelity of the mitochondrial DNA in Toxoplasma, reveals a novel mechanism for atovaquone resistance, and exposes the physiological plasticity of this important human pathogen.
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44
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Identification of a New Isoindole-2-yl Scaffold as a Qo and Qi Dual Inhibitor of Cytochrome bc 1 Complex: Virtual Screening, Synthesis, and Biochemical Assay. Interdiscip Sci 2017; 10:781-791. [PMID: 28921079 DOI: 10.1007/s12539-017-0241-8] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/27/2016] [Revised: 05/13/2017] [Accepted: 05/22/2017] [Indexed: 10/18/2022]
Abstract
Respiratory chain ubiquinol-cytochrome (cyt) c oxidoreductase (cyt bc 1 or complex III) has been demonstrated as a promising target for numerous antibiotics and fungicide applications. In this study, a virtual screening of NCI diversity database was carried out in order to find novel Qo/Qi cyt bc 1 complex inhibitors. Structure-based virtual screening and molecular docking methodology were employed to further screen compounds with inhibition activity against cyt bc 1 complex after extensive reliability validation protocol with cross-docking method and identification of the best score functions. Subsequently, the application of rational filtering procedure over the target database resulted in the elucidation of a novel class of cyt bc 1 complex potent inhibitors with comparable binding energies and biological activities to those of the standard inhibitor, antimycin.
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45
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Characterization of the Activities of Dinuclear Thiolato-Bridged Arene Ruthenium Complexes against Toxoplasma gondii. Antimicrob Agents Chemother 2017; 61:AAC.01031-17. [PMID: 28652238 DOI: 10.1128/aac.01031-17] [Citation(s) in RCA: 30] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/17/2017] [Accepted: 06/22/2017] [Indexed: 12/13/2022] Open
Abstract
The in vitro effects of 18 dinuclear thiolato-bridged arene ruthenium complexes (1 monohiolato compound, 4 dithiolato compounds, and 13 trithiolato compounds), originally designed as anticancer agents, on the apicomplexan parasite Toxoplasma gondii grown in human foreskin fibroblast (HFF) host cells were studied. Some trithiolato compounds exhibited antiparasitic efficacy at concentrations of 250 nM and below. Among those, complex 1 and complex 2 inhibited T. gondii proliferation with 50% inhibitory concentrations (IC50s) of 34 and 62 nM, respectively, and they did not affect HFFs at dosages of 200 μM or above, resulting in selectivity indices of >23,000. The IC50s of complex 9 were 1.2 nM for T. gondii and above 5 μM for HFFs. Transmission electron microscopy detected ultrastructural alterations in the matrix of the parasite mitochondria at the early stages of treatment, followed by a more pronounced destruction of tachyzoites. However, none of the three compounds applied at 250 nM for 15 days was parasiticidal. By affinity chromatography using complex 9 coupled to epoxy-activated Sepharose followed by mass spectrometry, T. gondii translation elongation factor 1α and two ribosomal proteins, RPS18 and RPL27, were identified to be potential binding proteins. In conclusion, organometallic ruthenium complexes exhibit promising activities against Toxoplasma, and the potential mechanisms of action of these compounds as well as their prospective applications for the treatment of toxoplasmosis are discussed.
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46
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Alday PH, Bruzual I, Nilsen A, Pou S, Winter R, Ben Mamoun C, Riscoe MK, Doggett JS. Genetic Evidence for Cytochrome b Qi Site Inhibition by 4(1H)-Quinolone-3-Diarylethers and Antimycin in Toxoplasma gondii. Antimicrob Agents Chemother 2017; 61:e01866-16. [PMID: 27919897 PMCID: PMC5278733 DOI: 10.1128/aac.01866-16] [Citation(s) in RCA: 43] [Impact Index Per Article: 6.1] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/25/2016] [Accepted: 11/29/2016] [Indexed: 11/20/2022] Open
Abstract
Toxoplasma gondii is an apicomplexan parasite that causes fatal and debilitating brain and eye disease. Endochinlike quinolones (ELQs) are preclinical compounds that are efficacious against apicomplexan-caused diseases, including toxoplasmosis, malaria, and babesiosis. Of the ELQs, ELQ-316 has demonstrated the greatest efficacy against acute and chronic experimental toxoplasmosis. Although genetic analyses in other organisms have highlighted the importance of the cytochrome bc1 complex Qi site for ELQ sensitivity, the mechanism of action of ELQs against T. gondii and the specific mechanism of ELQ-316 remain unknown. Here, we describe the selection and genetic characterization of T. gondii clones resistant to ELQ-316. A T. gondii strain selected under ELQ-316 drug pressure was found to possess a Thr222-Pro amino acid substitution that confers 49-fold resistance to ELQ-316 and 19-fold resistance to antimycin, a well-characterized Qi site inhibitor. These findings provide further evidence for ELQ Qi site inhibition in T. gondii and greater insight into the interactions of Qi site inhibitors with the apicomplexan cytochrome bc1 complex.
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Affiliation(s)
- P Holland Alday
- Division of Infectious Diseases, Oregon Health & Science University, Portland, Oregon, USA
| | - Igor Bruzual
- Department of Research and Development, Portland VA Medical Center, Portland, Oregon, USA
| | - Aaron Nilsen
- Department of Research and Development, Portland VA Medical Center, Portland, Oregon, USA
| | - Sovitj Pou
- Department of Research and Development, Portland VA Medical Center, Portland, Oregon, USA
| | - Rolf Winter
- Department of Research and Development, Portland VA Medical Center, Portland, Oregon, USA
| | - Choukri Ben Mamoun
- Department of Internal Medicine, Section of Infectious Diseases, Yale School of Medicine, New Haven, Connecticut, USA
| | - Michael K Riscoe
- Department of Research and Development, Portland VA Medical Center, Portland, Oregon, USA
| | - J Stone Doggett
- Division of Infectious Diseases, Oregon Health & Science University, Portland, Oregon, USA
- Department of Research and Development, Portland VA Medical Center, Portland, Oregon, USA
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47
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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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48
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Lemieux JE, Tran AD, Freimark L, Schaffner SF, Goethert H, Andersen KG, Bazner S, Li A, McGrath G, Sloan L, Vannier E, Milner D, Pritt B, Rosenberg E, Telford S, Bailey JA, Sabeti PC. A global map of genetic diversity in Babesia microti reveals strong population structure and identifies variants associated with clinical relapse. Nat Microbiol 2016; 1:16079. [PMID: 27572973 DOI: 10.1038/nmicrobiol.2016.79] [Citation(s) in RCA: 64] [Impact Index Per Article: 8.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/16/2015] [Accepted: 04/28/2016] [Indexed: 11/09/2022]
Abstract
Human babesiosis caused by Babesia microti is an emerging tick-borne zoonosis of increasing importance due to its rising incidence and expanding geographic range(1). Infection with this organism, an intraerythrocytic parasite of the phylum Apicomplexa, causes a febrile syndrome similar to malaria(2). Relapsing disease is common among immunocompromised and asplenic individuals(3,4) and drug resistance has recently been reported(5). To investigate the origin and genetic diversity of this parasite, we sequenced the complete genomes of 42 B. microti samples from around the world, including deep coverage of clinical infections at endemic sites in the continental USA. Samples from the continental USA segregate into a Northeast lineage and a Midwest lineage, with subsequent divergence of subpopulations along geographic lines. We identify parasite variants that associate with relapsing disease, including amino acid substitutions in the atovaquone-binding regions of cytochrome b (cytb) and the azithromycin-binding region of ribosomal protein subunit L4 (rpl4). Our results shed light on the origin, diversity and evolution of B. microti, suggest possible mechanisms for clinical relapse, and create the foundation for further research on this emerging pathogen.
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Affiliation(s)
- Jacob E Lemieux
- The Broad Institute of MIT Division of Health Sciences and and MIT, Cambridge 02142, Massachusetts, USA.,Department of Medicine, Massachusetts General Hospital, Boston, Massachusetts 02114, USA
| | - Alice D Tran
- Program in Bioinformatics and Integrative Biology, University of Massachusetts Medical School, Worcester, Massachusetts 01605, USA
| | - Lisa Freimark
- The Broad Institute of MIT Division of Health Sciences and and MIT, Cambridge 02142, Massachusetts, USA
| | - Stephen F Schaffner
- The Broad Institute of MIT Division of Health Sciences and and MIT, Cambridge 02142, Massachusetts, USA
| | - Heidi Goethert
- Tufts School of Veterinary Medicine, North Grafton, Massachusetts 01536, USA
| | - Kristian G Andersen
- The Broad Institute of MIT Division of Health Sciences and and MIT, Cambridge 02142, Massachusetts, USA.,The Scripps Research Institute, La Jolla, California 92037, USA
| | - Suzane Bazner
- Department of Medicine, Massachusetts General Hospital, Boston, Massachusetts 02114, USA
| | - Amy Li
- Koch Institute for Integrative Cancer Research at MIT, Cambridge, Massachusetts 02142, USA
| | - Graham McGrath
- Department of Medicine, Massachusetts General Hospital, Boston, Massachusetts 02114, USA
| | - Lynne Sloan
- Department of Pathology, The Mayo Clinic, Rochester, Minnesota 55905, USA
| | - Edouard Vannier
- Division of Geographic Medicine and Infectious Disease, Tufts Medical Center, Boston, Massachusetts 02111, USA
| | - Dan Milner
- Department of Pathology, Brigham and Women's Hospital, Boston, Massachusetts 02115, USA
| | - Bobbi Pritt
- Department of Pathology, The Mayo Clinic, Rochester, Minnesota 55905, USA
| | - Eric Rosenberg
- Department of Medicine, Massachusetts General Hospital, Boston, Massachusetts 02114, USA.,Department of Pathology, Massachusetts General Hospital, Boston, Massachusetts 02114, USA
| | - Sam Telford
- Tufts School of Veterinary Medicine, North Grafton, Massachusetts 01536, USA
| | - Jeffrey A Bailey
- Program in Bioinformatics and Integrative Biology, University of Massachusetts Medical School, Worcester, Massachusetts 01605, USA.,Department of Medicine, University of Massachusetts Medical School, Worcester, Massachusetts 01655, USA
| | - Pardis C Sabeti
- The Broad Institute of MIT Division of Health Sciences and and MIT, Cambridge 02142, Massachusetts, USA.,Department of Evolutionary and Organismic Biology, MIT Division of Health Sciences and University, Cambridge, Massachusetts 02138, USA
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49
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Gajurel K, Gomez C, Dhakal R, Vogel H, Montoya J. Failure of primary atovaquone prophylaxis for prevention of toxoplasmosis in hematopoietic cell transplant recipients. Transpl Infect Dis 2016; 18:446-452. [DOI: 10.1111/tid.12532] [Citation(s) in RCA: 16] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/23/2015] [Revised: 11/10/2015] [Accepted: 01/31/2016] [Indexed: 11/29/2022]
Affiliation(s)
- K. Gajurel
- Division of Infectious Diseases and Geographic Medicine; School of Medicine; Stanford University; Stanford California USA
| | - C.A. Gomez
- Division of Infectious Diseases and Geographic Medicine; School of Medicine; Stanford University; Stanford California USA
| | - R. Dhakal
- Toxoplasma Serology Laboratory; National Reference Center for the Study and Diagnosis of Toxoplasmosis; Palo Alto California USA
| | - H. Vogel
- Department of Pathology; School of Medicine; Stanford University; Stanford California USA
| | - J.G. Montoya
- Division of Infectious Diseases and Geographic Medicine; School of Medicine; Stanford University; Stanford California USA
- Toxoplasma Serology Laboratory; National Reference Center for the Study and Diagnosis of Toxoplasmosis; Palo Alto California USA
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50
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Drug Repurposing Screening Identifies Novel Compounds That Effectively Inhibit Toxoplasma gondii Growth. mSphere 2016; 1:mSphere00042-15. [PMID: 27303726 PMCID: PMC4894684 DOI: 10.1128/msphere.00042-15] [Citation(s) in RCA: 57] [Impact Index Per Article: 7.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/28/2015] [Accepted: 02/11/2016] [Indexed: 01/16/2023] Open
Abstract
The urgent need to develop new antimicrobial therapies has spawned the development of repurposing screens in which well-studied drugs and other types of compounds are tested for potential off-label uses. As a proof-of-principle screen to identify compounds effective against Toxoplasma gondii, we screened a collection of 1,120 compounds for the ability to significantly reduce Toxoplasma replication. A total of 94 compounds blocked parasite replication with 50% inhibitory concentrations of <5 µM. A significant number of these compounds are established inhibitors of dopamine or estrogen signaling. Follow-up experiments with the dopamine receptor inhibitor pimozide revealed that the drug impacted both parasite invasion and replication but did so independently of inhibition of dopamine or other neurotransmitter receptor signaling. Tamoxifen, which is an established inhibitor of the estrogen receptor, also reduced parasite invasion and replication. Even though Toxoplasma can activate the estrogen receptor, tamoxifen inhibits parasite growth independently of this transcription factor. Tamoxifen is also a potent inducer of autophagy, and we find that the drug stimulates recruitment of the autophagy marker light chain 3-green fluorescent protein onto the membrane of the vacuolar compartment in which the parasite resides and replicates. In contrast to other antiparasitic drugs, including pimozide, tamoxifen treatment of infected cells leads to a time-dependent elimination of intracellular parasites. Taken together, these data suggest that tamoxifen restricts Toxoplasma growth by inducing xenophagy or autophagic destruction of this obligate intracellular parasite. IMPORTANCE There is an urgent need to develop new therapies to treat microbial infections, and the repurposing of well-characterized compounds is emerging as one approach to achieving this goal. Using the protozoan parasite Toxoplasma gondii, we screened a library of 1,120 compounds and identified several compounds with significant antiparasitic activities. Among these were pimozide and tamoxifen, which are well-characterized drugs prescribed to treat patients with psychiatric disorders and breast cancer, respectively. The mechanisms by which these compounds target these disorders are known, but we show here that these drugs kill Toxoplasma through novel pathways, highlighting the potential utility of off-target effects in the treatment of infectious diseases.
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