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Vijayasurya, Gupta S, Shah S, Pappachan A. Drug repurposing for parasitic protozoan diseases. PROGRESS IN MOLECULAR BIOLOGY AND TRANSLATIONAL SCIENCE 2024; 207:23-58. [PMID: 38942539 DOI: 10.1016/bs.pmbts.2024.05.001] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/30/2024]
Abstract
Protozoan parasites are major hazards to human health, society, and the economy, especially in equatorial regions of the globe. Parasitic diseases, including leishmaniasis, malaria, and others, contribute towards majority of morbidity and mortality. Around 1.1 million people die from these diseases annually. The lack of licensed vaccinations worsens the worldwide impact of these diseases, highlighting the importance of safe and effective medications for their prevention and treatment. However, the appearance of drug resistance in parasites continuously affects the availability of medications. The demand for novel drugs motivates global antiparasitic drug discovery research, necessitating the implementation of many innovative ways to maintain a continuous supply of promising molecules. Drug repurposing has come out as a compelling tool for drug development, offering a cost-effective and efficient alternative to standard de novo approaches. A thorough examination of drug repositioning candidates revealed that certain drugs may not benefit significantly from their original indications. Still, they may exhibit more pronounced effects in other disorders. Furthermore, certain medications can produce a synergistic effect, resulting in enhanced therapeutic effectiveness when given together. In this chapter, we outline the approaches employed in drug repurposing (sometimes referred to as drug repositioning), propose novel strategies to overcome these hurdles and fully exploit the promise of drug repurposing. We highlight a few major human protozoan diseases and a range of exemplary drugs repurposed for various protozoan infections, providing excellent outcomes for each disease.
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Affiliation(s)
- Vijayasurya
- School of Life Sciences, Central University of Gujarat, Gandhinagar, Gujarat, India
| | - Swadha Gupta
- School of Life Sciences, Central University of Gujarat, Gandhinagar, Gujarat, India
| | - Smit Shah
- School of Life Sciences, Central University of Gujarat, Gandhinagar, Gujarat, India
| | - Anju Pappachan
- School of Life Sciences, Central University of Gujarat, Gandhinagar, Gujarat, India.
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Ullah W, Wu WF, Malak N, Nasreen N, Swelum AA, Marcelino LA, Niaz S, Khan A, Ben Said M, Chen CC. Computational investigation of turmeric phytochemicals targeting PTR1 enzyme of Leishmania species. Heliyon 2024; 10:e27907. [PMID: 38533011 PMCID: PMC10963314 DOI: 10.1016/j.heliyon.2024.e27907] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/15/2023] [Revised: 03/06/2024] [Accepted: 03/07/2024] [Indexed: 03/28/2024] Open
Abstract
In this study, we used in silico techniques to identify available parasite treatments, representing a promising therapeutic avenue. Building upon our computational initiatives aimed at discovering natural inhibitors for various target enzymes from parasites causing neglected tropical diseases (NTDs), we present novel findings on three turmeric-derived phytochemicals as inhibitors of Leishmania pteridine reductase I (PTR1) through in silico methodologies. PTR1, a crucial enzyme in the unique folate metabolism of trypanosomatid parasites, holds established therapeutic significance. Employing MOE software, a molecular docking analysis assesses the efficacy of turmeric phytochemicals against Leishmania PTR1. Validation of the docking protocol is confirmed with an RMSD value of 2. Post-docking, compounds displaying notable interactions with critical residues and binding affinities ranging between -6 and -8 kcal/mol are selected for interaction pattern exploration. Testing twelve turmeric phytochemicals, including curcumin, zingiberene, curcumol, curcumenol, eugenol, bisdemethoxycurcumin, tetrahydrocurcumin, tryethylcurcumin, turmerones, turmerin, demethoxycurcumin, and turmeronols, revealed binding affinities ranging from -5.5 to -8 kcal/mol. Notably, curcumin, demethoxycurcumin, and bisdemethoxycurcumin exhibit binding affinities within -6.5 to -8 kcal/mol and establish substantial interactions with catalytic residues. These phytochemicals hold promise as lead structures for rational drug design targeting Leishmania spp. PTR in future applications. This work underscores the potential of these identified phytochemicals in the development of more effective inhibitors, demonstrating their relevance in addressing neglected tropical diseases caused by parasites.
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Affiliation(s)
- Wasia Ullah
- Department of Zoology, Abdul Wali Khan University Mardan, Mardan, 23200, Pakistan
| | - Wen-Feng Wu
- Department of Radiology, Ditmanson Medical Foundation Chia-Yi Christian Hospital, Chiayi, 600, Taiwan
| | - Nosheen Malak
- Department of Zoology, Abdul Wali Khan University Mardan, Mardan, 23200, Pakistan
| | - Nasreen Nasreen
- Department of Zoology, Abdul Wali Khan University Mardan, Mardan, 23200, Pakistan
| | - Ayman A. Swelum
- Department of Animal Production, College of Food and Agriculture Sciences, King Saud University, Riyadh, 1451, Saudi Arabia
| | - Liliana Aguilar Marcelino
- National Center for Disciplinary Research in Animal Health and Safety (INIFAP), Km 11 Federal Road Cuernavaca-Cuautla, 62550, Jiutepec, Morelos, Mexico
| | - Sadaf Niaz
- Department of Zoology, Abdul Wali Khan University Mardan, Mardan, 23200, Pakistan
| | - Adil Khan
- Department of Zoology, Bacha Khan University Charsadda, Charsadda, 24420, Pakistan
- Department of Biology, Mount Allison University, Sackville, E4L 1G7, New Brunswick, Canada
| | - Mourad Ben Said
- Laboratory of Microbiology, National School of Veterinary Medicine of Sidi Thabet, University of Manouba, Manouba, 2010, Tunisia
- Department of Basic Sciences, Higher Institute of Biotechnology of Sidi Thabet, University of Manouba, Manouba, 2010, Tunisia
| | - Chien-Chin Chen
- Department of Biotechnology and Bioindustry Sciences, College of Bioscience and Biotechnology, National Cheng Kung University, Tainan, 701, Taiwan
- Department of Pathology, Ditmanson Medical Foundation Chia-Yi Christian Hospital, Chiayi, 600, Taiwan
- Department of Cosmetic Science, Chia Nan University of Pharmacy and Science, Tainan, 717, Taiwan
- Ph.D. Program in Translational Medicine, Rong Hsing Research Center for Translational Medicine, National Chung Hsing University, Taichung, 40227, Taiwan
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Imidazo[1,2-b]pyridazine as privileged scaffold in medicinal chemistry: An extensive review. Eur J Med Chem 2021; 226:113867. [PMID: 34607244 DOI: 10.1016/j.ejmech.2021.113867] [Citation(s) in RCA: 15] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/28/2021] [Revised: 09/09/2021] [Accepted: 09/20/2021] [Indexed: 01/03/2023]
Abstract
Imidazo[1,2-b]pyridazine scaffold represents an important class of heterocyclic nucleus which provides various bioactives molecules. Among them, the successful kinase inhibitor ponatinib led to a resurgence of interest in exploring new imidazo[1,2-b]pyridazine-containing derivatives for their putative therapeutic applications in medicine. This present review intends to provide a state-of-the-art of this framework in medicinal chemistry from 1966 to nowadays, unveiling different aspects of its structure-activity relationships (SAR). This extensive literature surveil may guide medicinal chemists for the quest of novel imidazo[1,2-b]pyridazine compounds with enhanced pharmacokinetics profile and efficiency.
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El Akkaoui A, Koubachi J, Guillaumet G, El Kazzouli S. Synthesis and Functionalization of Imidazo[1,2‐
b
]Pyridazine by Means of Metal‐Catalyzed Cross‐Coupling Reactions. ChemistrySelect 2021. [DOI: 10.1002/slct.202101636] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/07/2022]
Affiliation(s)
- Ahmed El Akkaoui
- Laboratory of Analytical and Molecular Chemistry (LCAM) Polydisciplinary Faculty of Safi Cadi Ayyad University, Sidi Bouzid, B.P. 4162 46000 Safi Morocco
| | - Jamal Koubachi
- Polydisciplinary Faculty of Taroudant Laboratory of Applied and Environmental Chemistry (LACAPE) Faculty of Sciences Ibn Zohr University of Agadir, B.P 271 83000 Taroudant Morocco
| | - Gérald Guillaumet
- Institute of Organic and Analytical Chemistry University of Orleans, UMR CNRS 7311, BP 6759 45067 Orleans Cedex 2 France
- Euromed Research Centre School of Engineering in Biomedical and Biotechnology Euromed University of Fes (UEMF) Route de Meknès 30000 Fez Morocco
| | - Saïd El Kazzouli
- Euromed Research Centre School of Engineering in Biomedical and Biotechnology Euromed University of Fes (UEMF) Route de Meknès 30000 Fez Morocco
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Khamesipour F, Razavi SM, Hejazi SH, Ghanadian SM. In vitro and in vivo Anti-Toxoplasma activity of Dracocephalum kotschyi essential oil. Food Sci Nutr 2021; 9:522-531. [PMID: 33473313 PMCID: PMC7802582 DOI: 10.1002/fsn3.2021] [Citation(s) in RCA: 11] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/12/2020] [Revised: 10/31/2020] [Accepted: 11/02/2020] [Indexed: 02/05/2023] Open
Abstract
Toxoplasma gondii is a zoonotic parasite of worldwide importance, responsible for toxoplasmosis in homeotherms. Although treatment options are readily available, most drugs often cause serious side effects. Extracts of Dracocephalum kotschyi (D. kotschyi) have shown significant pharmacological activity against various parasites, viruses, and bacteria. In this study, we evaluated the anti-T. gondii activity in vitro and in vivo of D. kotschyi essential oil. The thiazolyl blue tetrazolium bromide (MTT) method was used to assess the anti-T. gondii activity and cytotoxicity of the essential oil. The presence of T. gondii was observed by Giemsa staining, and the viability was evaluated by the trypan blue staining method. Furthermore, the survival rate of acutely infected mice was evaluated by intraperitoneal injecting of the essential oil (50, 100, and 200 mg kg-1 day-1) for five days after infection with 2 × 104 tachyzoites. Essential oil, negative, and positive controls that showed the best toxoplasmacidal activity were assayed in triplicate at each concentration. The essential oil exhibited the highest anti-Toxoplasma activity with a half-maximal inhibitory concentration (IC50) of 9.94 ± 0.38 µg, with a selectivity index of 2.463. On Vero cells, the CC50 of the oil was 24.49 ± 0.96 µg and exhibited a significant anti-Toxoplasma activity. Moreover, the treatment by essential oil significantly increased the survival rate compared to untreated infected control. In conclusion, the essential oil might be a useful compound, and with more testing, it may be an excellent alternative to standard chemical drugs in the treatment of toxoplasmosis.
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Affiliation(s)
- Faham Khamesipour
- Department of PathobiologySchool of Veterinary MedicineShiraz UniversityShirazIran
| | - Seyed Mostafa Razavi
- Department of PathobiologySchool of Veterinary MedicineShiraz UniversityShirazIran
| | - Seyed Hossein Hejazi
- Department of Parasitology and MycologySkin Diseases and Leishmaniasis Research CenterSchool of MedicineIsfahan University of Medical SciencesIsfahanIran
| | - Seyed Mustafa Ghanadian
- Department of PharmacognosyIsfahan Pharmaceutical Sciences Research CenterIsfahan University of Medical SciencesIsfahanIran
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Hulverson MA, Bruzual I, McConnell EV, Huang W, Vidadala RSR, Choi R, Arnold SLM, Whitman GR, McCloskey MC, Barrett LK, Rivas KL, Scheele S, DeRocher AE, Parsons M, Ojo KK, Maly DJ, Fan E, Van Voorhis WC, Doggett JS. Pharmacokinetics and In Vivo Efficacy of Pyrazolopyrimidine, Pyrrolopyrimidine, and 5-Aminopyrazole-4-Carboxamide Bumped Kinase Inhibitors against Toxoplasmosis. J Infect Dis 2020; 219:1464-1473. [PMID: 30423128 DOI: 10.1093/infdis/jiy664] [Citation(s) in RCA: 10] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/03/2018] [Accepted: 11/12/2018] [Indexed: 12/19/2022] Open
Abstract
Bumped kinase inhibitors (BKIs) have been shown to be potent inhibitors of Toxoplasma gondii calcium-dependent protein kinase 1. Pyrazolopyrimidine and 5-aminopyrazole-4-carboxamide scaffold-based BKIs are effective in acute and chronic experimental models of toxoplasmosis. Through further exploration of these 2 scaffolds and a new pyrrolopyrimidine scaffold, additional compounds have been identified that are extremely effective against acute experimental toxoplasmosis. The in vivo efficacy of these BKIs demonstrates that the cyclopropyloxynaphthyl, cyclopropyloxyquinoline, and 2-ethoxyquinolin-6-yl substituents are associated with efficacy across scaffolds. In addition, a broad range of plasma concentrations after oral dosing resulted from small structural changes to the BKIs. These select BKIs include anti-Toxoplasma compounds that are effective against acute experimental toxoplasmosis and are not toxic in human cell assays, nor to mice when administered for therapy. The BKIs described here are promising late leads for improving anti-Toxoplasma therapy.
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Affiliation(s)
- Matthew A Hulverson
- Department of Medicine, Division of Allergy and Infectious Diseases, Center for Emerging and Re-Emerging Infectious Diseases
| | - Igor Bruzual
- Veterans Affairs Portland Health Care System, Oregon
| | | | - Wenlin Huang
- Department of Biochemistry, University of Washington, Seattle
| | | | - Ryan Choi
- Department of Medicine, Division of Allergy and Infectious Diseases, Center for Emerging and Re-Emerging Infectious Diseases
| | - Samuel L M Arnold
- Department of Medicine, Division of Allergy and Infectious Diseases, Center for Emerging and Re-Emerging Infectious Diseases
| | - Grant R Whitman
- Department of Medicine, Division of Allergy and Infectious Diseases, Center for Emerging and Re-Emerging Infectious Diseases
| | - Molly C McCloskey
- Department of Medicine, Division of Allergy and Infectious Diseases, Center for Emerging and Re-Emerging Infectious Diseases
| | - Lynn K Barrett
- Department of Medicine, Division of Allergy and Infectious Diseases, Center for Emerging and Re-Emerging Infectious Diseases
| | - Kasey L Rivas
- Department of Medicine, Division of Allergy and Infectious Diseases, Center for Emerging and Re-Emerging Infectious Diseases
| | | | - Amy E DeRocher
- Center for Infectious Disease Research, Seattle, Washington
| | | | - Kayode K Ojo
- Department of Medicine, Division of Allergy and Infectious Diseases, Center for Emerging and Re-Emerging Infectious Diseases
| | - Dustin J Maly
- Department of Biochemistry, University of Washington, Seattle.,Department of Chemistry, University of Washington, Seattle
| | - Erkang Fan
- Department of Biochemistry, University of Washington, Seattle
| | - Wesley C Van Voorhis
- Department of Medicine, Division of Allergy and Infectious Diseases, Center for Emerging and Re-Emerging Infectious Diseases
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Deng Y, Wu T, Zhai SQ, Li CH. Recent progress on anti-Toxoplasma drugs discovery: Design, synthesis and screening. Eur J Med Chem 2019; 183:111711. [PMID: 31585276 DOI: 10.1016/j.ejmech.2019.111711] [Citation(s) in RCA: 20] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/09/2019] [Revised: 08/27/2019] [Accepted: 09/16/2019] [Indexed: 01/30/2023]
Abstract
Toxoplasma gondii severely threaten the health of immunocompromised patients and pregnant women as this parasite can cause several disease, including brain and eye disease. Current treatment for toxoplasmosis commonly have high cytotoxic side effects on host and require long durations ranging from one week to more than one year. The regiments lack efficacy to eradicate T. gondii tissue cysts to cure chromic infection results in the needs for long treatment and relapsing disease. In addition, there has not been approved drugs for treating the pregnant women infected by T. gondii. Moreover, Toxoplasma vaccine researches face a wide variety of challenges. Developing high efficient and low toxic agents against T. gondii is urgent and important. Over the last decade, tremendous progress have been made in identifying and developing novel compounds for the treatment of toxoplasmosis. This review summarized and discussed recent advances between 2009 and 2019 in exploring effective agents against T. gondii from five aspects of drug discovery.
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Affiliation(s)
- Yu Deng
- Institute of Veterinary Sciences & Pharmaceuticals, Chongqing Academy of Animal Sciences, Rongchang, 402460, China
| | - Tao Wu
- Institute of Veterinary Sciences & Pharmaceuticals, Chongqing Academy of Animal Sciences, Rongchang, 402460, China
| | - Shao-Qin Zhai
- Institute of Veterinary Sciences & Pharmaceuticals, Chongqing Academy of Animal Sciences, Rongchang, 402460, China
| | - Cheng-Hong Li
- Institute of Veterinary Sciences & Pharmaceuticals, Chongqing Academy of Animal Sciences, Rongchang, 402460, China.
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Lapinskas PJ, Ben-Harari RR. Perspective on current and emerging drugs in the treatment of acute and chronic toxoplasmosis. Postgrad Med 2019; 131:589-596. [PMID: 31399001 DOI: 10.1080/00325481.2019.1655258] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/15/2022]
Abstract
No new drugs for treatment of toxoplasmosis have been approved in over 60 years, despite the burden of toxoplasmosis on human society. The small selection of effective drugs is limited by important side effects, often limiting patient use. This perspective highlights promising late-stage drug candidates in the treatment of toxoplasmosis. Presently, drugs target the tachyzoite form of the parasite Toxoplasma gondii responsible for the acute infection but do not eradicate the tissue cyst form underlying chronic infection. Pyrimethamine - the first-line and only approved drug for treatment of toxoplasmosis in the United States - inhibits parasite DNA synthesis by inhibiting dihydrofolate reductase (DHFR). Two novel DHFR inhibitors with improved potency and selectivity for parasite DHFR over human DHFR are in clinical-stage development. One of the most advanced and promising therapeutic targets, demonstrating potential to treat both acute and chronic toxoplasmosis, is the calcium-dependent protein kinase 1 (CDPK1) which plays an essential role in the intracellular replicative cycle of the parasite, and has no direct mammalian homolog. Two CDPK1 inhibitor programs have identified potent and selective lead series, demonstrating acceptable systemic and CNS exposure, and in vivo efficacy in animal models of acute and chronic infection. Physicians need a better arsenal of parasiticidal drugs for the treatment of toxoplasmosis, particularly those active against tissue cysts.
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Cervantes-Valencia ME, Hermosilla C, Alcalá-Canto Y, Tapia G, Taubert A, Silva LMR. Antiparasitic Efficacy of Curcumin Against Besnoitia besnoiti Tachyzoites in vitro. Front Vet Sci 2019; 5:333. [PMID: 30687723 PMCID: PMC6336690 DOI: 10.3389/fvets.2018.00333] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/10/2018] [Accepted: 12/14/2018] [Indexed: 01/29/2023] Open
Abstract
Besnoitia besnoiti is the causative agent of bovine besnoitiosis. B. besnoiti infections lead to reduced fertility and productivity in cattle causing high economic losses, not only in Europe, but also in Asia and Africa. Mild to severe clinical signs, such as anasarca, oedema, orchitis, hyperkeratosis, and characteristic skin and mucosal cysts, are due to B. besnoiti tachyzoite and bradyzoite replication in intermediate host tissues. So far, there are no commercially available effective drugs against this parasite. Curcumin, a polyphenolic compound from Curcuma longa rhizome is well-known for its antioxidant, anti-inflammatory, immunomodulatory and also anti-protozoan effects. Hence, the objective of this study was to evaluate the effects of curcumin on viability, motility, invasive capacity, and proliferation of B. besnoiti tachyzoites replicating in primary bovine umbilical vein endothelial cells (BUVEC) in vitro. Functional inhibition assays revealed that curcumin treatments reduce tachyzoite viability and induce lethal effects in up to 57% of tachyzoites (IC50 in 5.93 μM). Referring to general motility, significant dose-dependent effects of curcumin treatments were observed. Interestingly, curcumin treatments only dampened helical gliding and twirling activities whilst longitudinal gliding motility was not significantly affected. In addition, curcumin pretreatments of tachyzoites resulted in a dose-dependent reduction of host cell invasion as detected by infections rates at 1 day p. i. These findings demonstrate feeding cattle with Curcuma longa rhizomes may represent a new strategy for besnoitiosis treatment.
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Affiliation(s)
- María Eugenia Cervantes-Valencia
- Graduate Program of Animal Health and Production, Facultad de Medicina Veterinaria y Zootecnia, Universidad Nacional Autónoma de México, Mexico City, Mexico
| | - Carlos Hermosilla
- Institute of Parasitology, Justus Liebig University Giessen, Giessen, Germany
| | - Yazmín Alcalá-Canto
- Department of Parasitology, Facultad de Medicina Veterinaria y Zootecnia, Universidad Nacional Autónoma de México, Mexico City, Mexico
| | - Graciela Tapia
- Department of Genetics and Biostatistics, Facultad de Medicina Veterinaria y Zootecnia, Universidad Nacional Autónoma de México, Mexico City, Mexico
| | - Anja Taubert
- Institute of Parasitology, Justus Liebig University Giessen, Giessen, Germany
| | - Liliana M. R. Silva
- Institute of Parasitology, Justus Liebig University Giessen, Giessen, Germany
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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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Montazeri M, Sharif M, Sarvi S, Mehrzadi S, Ahmadpour E, Daryani A. A Systematic Review of In vitro and In vivo Activities of Anti -Toxoplasma Drugs and Compounds (2006-2016). Front Microbiol 2017; 8:25. [PMID: 28163699 PMCID: PMC5247447 DOI: 10.3389/fmicb.2017.00025] [Citation(s) in RCA: 96] [Impact Index Per Article: 13.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/01/2016] [Accepted: 01/05/2017] [Indexed: 11/23/2022] Open
Abstract
The currently available anti-Toxoplasma agents have serious limitations. This systematic review was performed to evaluate drugs and new compounds used for the treatment of toxoplasmosis. Data was systematically collected from published papers on the efficacy of drugs/compounds used against Toxoplasma gondii (T. gondii) globally during 2006-2016. The searched databases were PubMed, Google Scholar, Science Direct, ISI Web of Science, EBSCO, and Scopus. One hundred and eighteen papers were eligible for inclusion in this systematic review, which were both in vitro and in vivo studies. Within this review, 80 clinically available drugs and a large number of new compounds with more than 39 mechanisms of action were evaluated. Interestingly, many of the drugs/compounds evaluated against T. gondii act on the apicoplast. Therefore, the apicoplast represents as a potential drug target for new chemotherapy. Based on the current findings, 49 drugs/compounds demonstrated in vitro half-maximal inhibitory concentration (IC50) values of below 1 μM, but most of them were not evaluated further for in vivo effectiveness. However, the derivatives of the ciprofloxacin, endochin-like quinolones and 1-[4-(4-nitrophenoxy) phenyl] propane-1-one (NPPP) were significantly active against T. gondii tachyzoites both in vitro and in vivo. Thus, these compounds are promising candidates for future studies. Also, compound 32 (T. gondii calcium-dependent protein kinase 1 inhibitor), endochin-like quinolones, miltefosine, rolipram abolish, and guanabenz can be repurposed into an effective anti-parasitic with a unique ability to reduce brain tissue cysts (88.7, 88, 78, 74, and 69%, respectively). Additionally, no promising drugs are available for congenital toxoplasmosis. In conclusion, as current chemotherapy against toxoplasmosis is still not satisfactory, development of well-tolerated and safe specific immunoprophylaxis in relaxing the need of dependence on chemotherapeutics is a highly valuable goal for global disease control. However, with the increasing number of high-risk individuals, and absence of a proper vaccine, continued efforts are necessary for the development of novel treatment options against T. gondii. Some of the novel compounds reviewed here may represent good starting points for the discovery of effective new drugs. In further, bioinformatic and in silico studies are needed in order to identify new potential toxoplasmicidal drugs.
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Affiliation(s)
- Mahbobeh Montazeri
- Toxoplasmosis Research Center, Mazandaran University of Medical SciencesSari, Iran
- Student Research Committee, Mazandaran University of Medical SciencesSari, Iran
| | - Mehdi Sharif
- Toxoplasmosis Research Center, Mazandaran University of Medical SciencesSari, Iran
- Department of Parasitology and Mycology, Sari Medical School, Mazandaran University of Medical SciencesSari, Iran
| | - Shahabeddin Sarvi
- Toxoplasmosis Research Center, Mazandaran University of Medical SciencesSari, Iran
- Department of Parasitology and Mycology, Sari Medical School, Mazandaran University of Medical SciencesSari, Iran
| | - Saeed Mehrzadi
- Department of Pharmacology, School of Medicine, Iran University of Medical Sciences TehranIran
| | - Ehsan Ahmadpour
- Drug Applied Research Center, Tabriz University of Medical SciencesTabriz, Iran
| | - Ahmad Daryani
- Toxoplasmosis Research Center, Mazandaran University of Medical SciencesSari, Iran
- Department of Parasitology and Mycology, Sari Medical School, Mazandaran University of Medical SciencesSari, Iran
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Chellan P, Sadler PJ, Land KM. Recent developments in drug discovery against the protozoal parasites Cryptosporidium and Toxoplasma. Bioorg Med Chem Lett 2017; 27:1491-1501. [PMID: 28242275 DOI: 10.1016/j.bmcl.2017.01.046] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/20/2016] [Revised: 01/12/2017] [Accepted: 01/13/2017] [Indexed: 11/19/2022]
Abstract
Apicomplexan parasites cause some of the most devastating human diseases, including malaria, toxoplasmosis, and cryptosporidiosis. New drug discovery is imperative in light of increased resistance. In this digest article, we briefly explore some of the recent and promising developments in new drug discovery against two apicomplexan parasites, Cryptosporidium and Toxoplasma.
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Affiliation(s)
- Prinessa Chellan
- Department of Chemistry, University of Warwick, Coventry, Warwickshire CV4 7AL, UK
| | - Peter J Sadler
- Department of Chemistry, University of Warwick, Coventry, Warwickshire CV4 7AL, UK
| | - Kirkwood M Land
- Department of Biological Sciences, University of the Pacific, Stockton, CA 95211, United States.
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Van Voorhis WC, Doggett JS, Parsons M, Hulverson MA, Choi R, Arnold SLM, Riggs MW, Hemphill A, Howe DK, Mealey RH, Lau AOT, Merritt EA, Maly DJ, Fan E, Ojo KK. Extended-spectrum antiprotozoal bumped kinase inhibitors: A review. Exp Parasitol 2017; 180:71-83. [PMID: 28065755 DOI: 10.1016/j.exppara.2017.01.001] [Citation(s) in RCA: 49] [Impact Index Per Article: 7.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/02/2016] [Revised: 01/02/2017] [Accepted: 01/04/2017] [Indexed: 01/08/2023]
Abstract
Many life-cycle processes in parasites are regulated by protein phosphorylation. Hence, disruption of essential protein kinase function has been explored for therapy of parasitic diseases. However, the difficulty of inhibiting parasite protein kinases to the exclusion of host orthologues poses a practical challenge. A possible path around this difficulty is the use of bumped kinase inhibitors for targeting calcium-dependent protein kinases that contain atypically small gatekeeper residues and are crucial for pathogenic apicomplexan parasites' survival and proliferation. In this article, we review efficacy against the kinase target, parasite growth in vitro, and in animal infection models, as well as the relevant pharmacokinetic and safety parameters of bumped kinase inhibitors.
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Affiliation(s)
- Wesley C Van Voorhis
- Department of Medicine, Division of Allergy and Infectious Diseases, Center for Emerging and Reemerging Infectious Diseases (CERID), University of Washington, Seattle, WA 98109, USA; Department of Global Health, University of Washington, Seattle, WA 98195, USA.
| | | | - Marilyn Parsons
- Department of Global Health, University of Washington, Seattle, WA 98195, USA; Center for Infectious Disease Research, Seattle, WA 98109, USA
| | - Matthew A Hulverson
- Department of Medicine, Division of Allergy and Infectious Diseases, Center for Emerging and Reemerging Infectious Diseases (CERID), University of Washington, Seattle, WA 98109, USA
| | - Ryan Choi
- Department of Medicine, Division of Allergy and Infectious Diseases, Center for Emerging and Reemerging Infectious Diseases (CERID), University of Washington, Seattle, WA 98109, USA
| | - Samuel L M Arnold
- Department of Medicine, Division of Allergy and Infectious Diseases, Center for Emerging and Reemerging Infectious Diseases (CERID), University of Washington, Seattle, WA 98109, USA
| | - Michael W Riggs
- School of Animal and Comparative Biomedical Sciences, College of Agriculture and Life Sciences, University of Arizona, Tucson, AZ 85721, USA
| | - Andrew Hemphill
- Institute of Parasitology, Vetsuisse Faculty, University of Bern, Berne, Switzerland
| | - Daniel K Howe
- Department of Veterinary Science, University of Kentucky, Lexington, KY 40546, USA
| | - Robert H Mealey
- Department of Veterinary Microbiology and Pathology, College of Veterinary Medicine, Washington State University, Pullman, WA 99164-7040, USA
| | - Audrey O T Lau
- The National Institutes of Health, NIAID, DEA, 5601 Fishers Lane, Rockville, MD 20892, USA
| | - Ethan A Merritt
- Department of Biochemistry, University of Washington, Seattle, WA 98195, USA
| | - Dustin J Maly
- Department of Chemistry, University of Washington, Seattle, WA 98195, USA
| | - Erkang Fan
- Department of Biochemistry, University of Washington, Seattle, WA 98195, USA
| | - Kayode K Ojo
- Department of Medicine, Division of Allergy and Infectious Diseases, Center for Emerging and Reemerging Infectious Diseases (CERID), University of Washington, Seattle, WA 98109, USA.
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14
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Review of Experimental Compounds Demonstrating Anti-Toxoplasma Activity. Antimicrob Agents Chemother 2016; 60:7017-7034. [PMID: 27600037 DOI: 10.1128/aac.01176-16] [Citation(s) in RCA: 28] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/11/2023] Open
Abstract
Toxoplasma gondii is a ubiquitous apicomplexan parasite capable of infecting humans and other animals. Current treatment options for T. gondii infection are limited and most have drawbacks, including high toxicity and low tolerability. Additionally, no FDA-approved treatments are available for pregnant women, a high-risk population due to transplacental infection. Therefore, the development of novel treatment options is needed. To aid this effort, this review highlights experimental compounds that, at a minimum, demonstrate inhibition of in vitro growth of T. gondii When available, host cell toxicity and in vivo data are also discussed. The purpose of this review is to facilitate additional development of anti-Toxoplasma compounds and potentially to extend our knowledge of the parasite.
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15
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Roslan II, Ng KH, Wu JE, Chuah GK, Jaenicke S. Synthesis of Disubstituted 3-Phenylimidazo[1,2-a]pyridines via a 2-Aminopyridine/CBrCl 3 α-Bromination Shuttle. J Org Chem 2016; 81:9167-9174. [PMID: 27606896 DOI: 10.1021/acs.joc.6b01714] [Citation(s) in RCA: 23] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/27/2023]
Abstract
A versatile protocol for the synthesis of disubstituted 3-phenylimidazo[1,2-a]pyridines by coupling 2-aminopyridine with phenylacetophenones, phenylacetones, or β-tetralone has been developed. Isolated yields of up to 97% were obtained at 80 °C within 5 h. The 2-aminopyridine/CBrCl3 system acts as an α-bromination shuttle by transferring Br from CBrCl3 to the α-carbon of the carbonyl moiety. This triggers a series of steps with double C-N/C-N bond formation to the final product. The distinct advantages of this protocol include the use of commercially available inexpensive substrates, simplicity of a metal-free one-pot synthesis, and ease of scale-up to multigram quantities.
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Affiliation(s)
- Irwan Iskandar Roslan
- Department of Chemistry, National University of Singapore , 3 Science Drive 3, Singapore, Singapore 117543
| | - Kian-Hong Ng
- Department of Chemistry, National University of Singapore , 3 Science Drive 3, Singapore, Singapore 117543
| | - Ji'-En Wu
- Department of Chemistry, National University of Singapore , 3 Science Drive 3, Singapore, Singapore 117543
| | - Gaik-Khuan Chuah
- Department of Chemistry, National University of Singapore , 3 Science Drive 3, Singapore, Singapore 117543
| | - Stephan Jaenicke
- Department of Chemistry, National University of Singapore , 3 Science Drive 3, Singapore, Singapore 117543
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16
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Abstract
INTRODUCTION Despite the fact that diseases caused by protozoan parasites represent serious challenges for public health, animal production and welfare, only a limited panel of drugs has been marketed for clinical applications. AREAS COVERED Herein, the authors investigate two strategies, namely whole organism screening and target-based drug design. The present pharmacopoeia has resulted from whole organism screening, and the mode of action and targets of selected drugs are discussed. However, the more recent extensive genome sequencing efforts and the development of dry and wet lab genomics and proteomics that allow high-throughput screening of interactions between micromolecules and recombinant proteins has resulted in target-based drug design as the predominant focus in anti-parasitic drug development. Selected examples of target-based drug design studies are presented, and calcium-dependent protein kinases, important drug targets in apicomplexan parasites, are discussed in more detail. EXPERT OPINION Despite the enormous efforts in target-based drug development, this approach has not yet generated market-ready antiprotozoal drugs. However, whole-organism screening approaches, comprising of both in vitro and in vivo investigations, should not be disregarded. The repurposing of already approved and marketed drugs could be a suitable strategy to avoid fastidious approval procedures, especially in the case of neglected or veterinary parasitoses.
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Affiliation(s)
- Joachim Müller
- a Institute of Parasitology, Vetsuisse Faculty , University of Bern , Bern , Switzerland
| | - Andrew Hemphill
- a Institute of Parasitology, Vetsuisse Faculty , University of Bern , Bern , Switzerland
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17
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Metabolic signatures of Besnoitia besnoiti-infected endothelial host cells and blockage of key metabolic pathways indicate high glycolytic and glutaminolytic needs of the parasite. Parasitol Res 2016; 115:2023-34. [PMID: 26852124 DOI: 10.1007/s00436-016-4946-0] [Citation(s) in RCA: 16] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/17/2015] [Accepted: 01/29/2016] [Indexed: 10/22/2022]
Abstract
Besnoitia besnoiti is an obligate intracellular and emerging coccidian parasite of cattle with a significant economic impact on cattle industry. During acute infection, fast-proliferating tachyzoites are continuously formed mainly in endothelial host cells of infected animals. Given that offspring formation is a highly energy and cell building block demanding process, the parasite needs to exploit host cellular metabolism to meet its metabolic demands. Here, we analyzed the metabolic signatures of B. besnoiti-infected endothelial host cells and aimed to influence parasite proliferation by inhibitors of specific metabolic pathways. The following inhibitors were tested: fluoro 2-deoxy-D-glucose and 2-deoxy-D-glucose (FDG, DG; inhibitors of glycolysis), 6-diazo-5-oxo-L-norleucin (DON; inhibitor of glutaminolysis), dichloroacetate (DCA; inhibitor of pyruvate dehydrogenase kinase which favorites channeling of glucose carbons into the TCA cycle) and adenosine-monophosphate (AMP; inhibitor of ribose 5-P synthesis). Overall, B. besnoiti infections of bovine endothelial cells induced a significant and infection rate-dependent increase of glucose, lactate, glutamine, glutamate, pyruvate, alanine, and serine conversion rates which together indicate a parasite-triggered up-regulation of glycolysis and glutaminolysis. Thus, addition of DON, FDG, and DG into the cultivation medium of B. besnoiti infected endothelial cells led to a dose-dependent inhibition of parasite replication (4 μM DON, 99.5 % inhibition; 2 mM FDG, 99.1 % inhibition; 2 mM DG, 93 % inhibition; and 8 mM DCA, 71.9 % inhibition). In contrast, AMP had no significant effects on total tachyzoite production up to a concentration of 20 mM. Together, these data may open new strategies for the development of therapeutics for B. besnoiti infections.
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18
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Silpa L, Niepceron A, Laurent F, Brossier F, Pénichon M, Enguehard-Gueiffier C, Abarbri M, Silvestre A, Petrignet J. Synthesis and evaluation of the anticoccidial activity of trifluoropyrido[1,2-a]pyrimidin-2-one derivatives. Bioorg Med Chem Lett 2016; 26:114-20. [DOI: 10.1016/j.bmcl.2015.11.018] [Citation(s) in RCA: 20] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/14/2015] [Revised: 11/04/2015] [Accepted: 11/06/2015] [Indexed: 11/26/2022]
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19
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Moine E, Dimier-Poisson I, Enguehard-Gueiffier C, Logé C, Pénichon M, Moiré N, Delehouzé C, Foll-Josselin B, Ruchaud S, Bach S, Gueiffier A, Debierre-Grockiego F, Denevault-Sabourin C. Development of new highly potent imidazo[1,2-b]pyridazines targeting Toxoplasma gondii calcium-dependent protein kinase 1. Eur J Med Chem 2015; 105:80-105. [PMID: 26479029 DOI: 10.1016/j.ejmech.2015.10.004] [Citation(s) in RCA: 22] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/17/2015] [Revised: 10/02/2015] [Accepted: 10/03/2015] [Indexed: 11/16/2022]
Abstract
Using a structure-based design approach, we have developed a new series of imidazo[1,2-b]pyridazines, targeting the calcium-dependent protein kinase-1 (CDPK1) from Toxoplasma gondii. Twenty derivatives were thus synthesized. Structure-activity relationships and docking studies confirmed the binding mode of these inhibitors within the ATP binding pocket of TgCDPK1. Two lead compounds (16a and 16f) were then identified, which were able to block TgCDPK1 enzymatic activity at low nanomolar concentrations, with a good selectivity profile against a panel of mammalian kinases. The potential of these inhibitors was confirmed in vitro on T. gondii growth, with EC50 values of 100 nM and 70 nM, respectively. These best candidates also displayed low toxicity to mammalian cells and were selected for further in vivo investigations on murine model of acute toxoplasmosis.
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Affiliation(s)
- Espérance Moine
- Université François-Rabelais de Tours, UMR1282 Infectiologie et Santé Publique, F-37000 Tours, France; INRA, UMR1282 Infectiologie et Santé Publique, F-37380 Nouzilly, France
| | - Isabelle Dimier-Poisson
- Université François-Rabelais de Tours, UMR1282 Infectiologie et Santé Publique, F-37000 Tours, France; INRA, UMR1282 Infectiologie et Santé Publique, F-37380 Nouzilly, France
| | - Cécile Enguehard-Gueiffier
- Université François-Rabelais de Tours, UMR1282 Infectiologie et Santé Publique, F-37000 Tours, France; INRA, UMR1282 Infectiologie et Santé Publique, F-37380 Nouzilly, France
| | - Cédric Logé
- Université de Nantes, Nantes Atlantique Universités, Laboratoire de Chimie Thérapeutique, Cibles et Médicaments des Infections et du Cancer, IICiMed-EA 1155, UFR de Sciences Pharmaceutiques et Biologiques, F-44035 Nantes, France
| | - Mélanie Pénichon
- Université François-Rabelais de Tours, UMR1282 Infectiologie et Santé Publique, F-37000 Tours, France; INRA, UMR1282 Infectiologie et Santé Publique, F-37380 Nouzilly, France
| | - Nathalie Moiré
- Université François-Rabelais de Tours, UMR1282 Infectiologie et Santé Publique, F-37000 Tours, France; INRA, UMR1282 Infectiologie et Santé Publique, F-37380 Nouzilly, France
| | - Claire Delehouzé
- USR3151 CNRS/UPMC, Plate-forme de Criblage KISSf (Kinase Inhibitor Specialized Screening Facility), Station Biologique de Roscoff, F-29688 Roscoff, France
| | - Béatrice Foll-Josselin
- USR3151 CNRS/UPMC, Plate-forme de Criblage KISSf (Kinase Inhibitor Specialized Screening Facility), Station Biologique de Roscoff, F-29688 Roscoff, France
| | - Sandrine Ruchaud
- USR3151 CNRS/UPMC, Plate-forme de Criblage KISSf (Kinase Inhibitor Specialized Screening Facility), Station Biologique de Roscoff, F-29688 Roscoff, France
| | - Stéphane Bach
- USR3151 CNRS/UPMC, Plate-forme de Criblage KISSf (Kinase Inhibitor Specialized Screening Facility), Station Biologique de Roscoff, F-29688 Roscoff, France
| | - Alain Gueiffier
- Université François-Rabelais de Tours, UMR1282 Infectiologie et Santé Publique, F-37000 Tours, France; INRA, UMR1282 Infectiologie et Santé Publique, F-37380 Nouzilly, France
| | - Françoise Debierre-Grockiego
- Université François-Rabelais de Tours, UMR1282 Infectiologie et Santé Publique, F-37000 Tours, France; INRA, UMR1282 Infectiologie et Santé Publique, F-37380 Nouzilly, France
| | - Caroline Denevault-Sabourin
- Université François-Rabelais de Tours, UMR1282 Infectiologie et Santé Publique, F-37000 Tours, France; INRA, UMR1282 Infectiologie et Santé Publique, F-37380 Nouzilly, France.
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20
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Lasch R, Heinrich MR. Zinc-Mediated Allylation and Benzylation of Phenylazocarboxylic Esters. J Org Chem 2015; 80:10412-20. [DOI: 10.1021/acs.joc.5b01978] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/19/2022]
Affiliation(s)
- Roman Lasch
- Department of Chemistry and
Pharmacy, Pharmaceutical Chemistry, Friedrich-Alexander-Universität Erlangen-Nürnberg, Schuhstraße 19, 91052 Erlangen, Germany
| | - Markus R. Heinrich
- Department of Chemistry and
Pharmacy, Pharmaceutical Chemistry, Friedrich-Alexander-Universität Erlangen-Nürnberg, Schuhstraße 19, 91052 Erlangen, Germany
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21
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Liénard E, Pop L, Prevot F, Grisez C, Mallet V, Raymond-Letron I, Bouhsira É, Franc M, Jacquiet P. Experimental infections of rabbits with proliferative and latent stages of Besnoitia besnoiti. Parasitol Res 2015; 114:3815-26. [PMID: 26143866 PMCID: PMC4562009 DOI: 10.1007/s00436-015-4612-y] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/14/2015] [Accepted: 06/25/2015] [Indexed: 11/26/2022]
Abstract
Cattle besnoitiosis due to Besnoitia besnoiti is spreading across Europe and is responsible for severe economic losses in newly infected herds. Experimentally speaking, rabbits have been found to be susceptible to this parasite. The adaptation of B. besnoiti to rabbits may offer a new, easier and cheaper model of investigation for this disease. This study compared the virulence between tachyzoites and bradyzoites of B. besnoiti in rabbits. Eighteen New Zealand rabbits were allocated into three groups of six animals each. The rabbits from the control (group C), "tachyzoite" (group T) and "bradyzoite" (group B) groups were subcutaneously injected in the right flank with 66 μg of ovalbumin, 6.10(6) tachyzoites (125th passage on Vero cells) and 6.10(6) bradyzoites (collected from a natural infected cow) of B. besnoiti, respectively. Clinical follow-up and blood sampling for serological survey and qPCR were performed during 10 weeks until euthanasia. Molecular and immunohistochemistry examination was achieved on 25 samples of tissue per rabbit. Seroconversion occurred in group T without any clinical signs. Rabbits of group B exhibited a febrile condition (temperature above 40 °C from day 8 to day 11 following injection) with positive qPCR in blood. Cysts of B. besnoiti were found on skin samples and organs of rabbits from group B in tissue explored with threshold cycle (Ct) values below 30. These results suggest a higher virulence of bradyzoites in rabbits than Vero cell-cultivated tachyzoites. The proposed model could be used to assess the in vivo effectiveness of vaccine or drugs against cattle besnoitiosis.
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Affiliation(s)
- Emmanuel Liénard
- UMR INRA/DGER 1225, INP - École Nationale Vétérinaire de Toulouse, Laboratoire de Parasitologie, 23 chemin des Capelles, F-31076, Toulouse, France,
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