1
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Petukhova VZ, Aboagye SY, Ardini M, Lullo RP, Fata F, Byrne ME, Gabriele F, Martin LM, Harding LNM, Gone V, Dangi B, Lantvit DD, Nikolic D, Ippoliti R, Effantin G, Ling WL, Johnson JJ, Thatcher GRJ, Angelucci F, Williams DL, Petukhov PA. Non-covalent inhibitors of thioredoxin glutathione reductase with schistosomicidal activity in vivo. Nat Commun 2023; 14:3737. [PMID: 37349300 PMCID: PMC10287695 DOI: 10.1038/s41467-023-39444-y] [Citation(s) in RCA: 3] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/28/2022] [Accepted: 06/12/2023] [Indexed: 06/24/2023] Open
Abstract
Only praziquantel is available for treating schistosomiasis, a disease affecting more than 200 million people. Praziquantel-resistant worms have been selected for in the lab and low cure rates from mass drug administration programs suggest that resistance is evolving in the field. Thioredoxin glutathione reductase (TGR) is essential for schistosome survival and a validated drug target. TGR inhibitors identified to date are irreversible and/or covalent inhibitors with unacceptable off-target effects. In this work, we identify noncovalent TGR inhibitors with efficacy against schistosome infections in mice, meeting the criteria for lead progression indicated by WHO. Comparisons with previous in vivo studies with praziquantel suggests that these inhibitors outperform the drug of choice for schistosomiasis against juvenile worms.
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Grants
- R33 AI127635 NIAID NIH HHS
- Division of Intramural Research, National Institute of Allergy and Infectious Diseases (Division of Intramural Research of the NIAID)
- Oncomelania hupensis subsp. hupensis, Chinese strain, infected with S. japonicum, Chinese strain, and Biomphalaria glabrata, strain NMRI, infected with S. mansoni, strain NMRI, were provided by the NIAID Schistosomiasis Resource Center for distribution through BEI Resources, NIAID, NIH. We are grateful to Dr. Guy Schoehn (Univ. Grenoble Alpes, CEA, CNRS, Institut de Biologie Structurale, Grenoble, France), Prof. Beatrice Vallone (Sapienza University of Rome, Italy) and Dr. Linda C. Montemiglio (IBPM, National Research Council, Italy) for helpful discussions of the cryo-EM studies. We acknowledge the Elettra-Sincrotrone Trieste (Italy) for support in X-ray data collections and the European Synchrotron Radiation Facility for provision of microscope time on CM01. The study was funded in part by US NIH/NIAID R33AI127635 to F.A., P.A.P., G.R.T. and D.L.W. This work benefited from access to Research Resources Centre and UICentre at University of Illinois at Chicago and used the platforms of the Grenoble Instruct-ERIC center (ISBG; UAR 3518 CNRS-CEA-UGA-EMBL) within the Grenoble Partnership for Structural Biology (PSB), supported by FRISBI (ANR-10-INBS-0005-02) and GRAL, financed within the University Grenoble Alpes graduate school (Ecoles Universitaires de Recherche) CBH-EUR-GS (ANR-17-EURE-0003). The IBS Electron Microscope facility is supported by the Auvergne Rhône-Alpes Region, the Fonds Feder, the Fondation pour la Recherche Médicale and GIS-IBiSA. The IBS acknowledges integration into the Interdisciplinary Research Institute of Grenoble (IRIG, CEA). M.A. has been supported by MIUR - Ministero dell'Istruzione Ministero dell'Università e della Ricerca (Ministry of Education, University and Research) under the national project FSE/FESR - PON Ricerca e Innovazione 2014-2020 (N° AIM1887574, CUP: E18H19000350007). We acknowledge OpenEye/Cadence for providing us with an academic license for the software used in these studies.
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Affiliation(s)
- Valentina Z Petukhova
- Department of Pharmaceutical Sciences, College of Pharmacy, University of Illinois at Chicago, Chicago, IL, USA
| | - Sammy Y Aboagye
- Department of Microbial Pathogens and Immunity, Rush University Medical Center, Chicago, IL, USA
| | - Matteo Ardini
- Department of Life, Health and Environmental Sciences, University of L'Aquila, L'Aquila, Italy
| | - Rachel P Lullo
- Department of Microbial Pathogens and Immunity, Rush University Medical Center, Chicago, IL, USA
| | - Francesca Fata
- Department of Life, Health and Environmental Sciences, University of L'Aquila, L'Aquila, Italy
| | - Margaret E Byrne
- Department of Microbial Pathogens and Immunity, Rush University Medical Center, Chicago, IL, USA
| | - Federica Gabriele
- Department of Life, Health and Environmental Sciences, University of L'Aquila, L'Aquila, Italy
| | - Lucy M Martin
- Department of Microbial Pathogens and Immunity, Rush University Medical Center, Chicago, IL, USA
| | - Luke N M Harding
- Department of Pharmaceutical Sciences, College of Pharmacy, University of Illinois at Chicago, Chicago, IL, USA
| | - Vamshikrishna Gone
- UICentre, Department of Pharmaceutical Sciences, College of Pharmacy, University of Illinois at Chicago, Chicago, IL, USA
| | - Bikash Dangi
- Department of Pharmacy Practice, College of Pharmacy, University of Illinois at Chicago, Chicago, IL, USA
| | - Daniel D Lantvit
- UICentre, Department of Pharmaceutical Sciences, College of Pharmacy, University of Illinois at Chicago, Chicago, IL, USA
| | - Dejan Nikolic
- Department of Pharmaceutical Sciences, College of Pharmacy, University of Illinois at Chicago, Chicago, IL, USA
| | - Rodolfo Ippoliti
- Department of Life, Health and Environmental Sciences, University of L'Aquila, L'Aquila, Italy
| | - Grégory Effantin
- University of Grenoble Alpes, CEA, CNRS, IBS, F-38000, Grenoble, France
| | - Wai Li Ling
- University of Grenoble Alpes, CEA, CNRS, IBS, F-38000, Grenoble, France
| | - Jeremy J Johnson
- Department of Pharmacy Practice, College of Pharmacy, University of Illinois at Chicago, Chicago, IL, USA
| | - Gregory R J Thatcher
- Department of Pharmacology & Toxicology, R. Ken Coit College of Pharmacy, University of Arizona, Tucson, AZ, USA
| | - Francesco Angelucci
- Department of Life, Health and Environmental Sciences, University of L'Aquila, L'Aquila, Italy.
| | - David L Williams
- Department of Microbial Pathogens and Immunity, Rush University Medical Center, Chicago, IL, USA.
| | - Pavel A Petukhov
- Department of Pharmaceutical Sciences, College of Pharmacy, University of Illinois at Chicago, Chicago, IL, USA.
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2
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Silveira GO, Coelho HS, Pereira ASA, Miyasato PA, Santos DW, Maciel LF, Olberg GGG, Tahira AC, Nakano E, Oliveira MLS, Amaral MS, Verjovski-Almeida S. Long non-coding RNAs are essential for Schistosoma mansoni pairing-dependent adult worm homeostasis and fertility. PLoS Pathog 2023; 19:e1011369. [PMID: 37146077 DOI: 10.1371/journal.ppat.1011369] [Citation(s) in RCA: 4] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/19/2022] [Revised: 05/17/2023] [Accepted: 04/18/2023] [Indexed: 05/07/2023] Open
Abstract
The trematode parasite Schistosoma mansoni causes schistosomiasis, which affects over 200 million people worldwide. Schistosomes are dioecious, with egg laying depending on the females' obligatory pairing with males. Long non-coding RNAs (lncRNAs) are transcripts longer than 200 nucleotides with low or no protein-coding potential that have been involved in other species with reproduction, stem cell maintenance, and drug resistance. In S. mansoni, we recently showed that the knockdown of one lncRNA affects the pairing status of these parasites. Here, we re-analyzed public RNA-Seq data from paired and unpaired adult male and female worms and their gonads, obtained from mixed-sex or single-sex cercariae infections, and found thousands of differentially expressed pairing-dependent lncRNAs among the 23 biological samples that were compared. The expression levels of selected lncRNAs were validated by RT-qPCR using an in vitro unpairing model. In addition, the in vitro silencing of three selected lncRNAs showed that knockdown of these pairing-dependent lncRNAs reduced cell proliferation in adult worms and their gonads, and are essential for female vitellaria maintenance, reproduction, and/or egg development. Remarkably, in vivo silencing of each of the three selected lncRNAs significantly reduced worm burden in infected mice by 26 to 35%. Whole mount in situ hybridization experiments showed that these pairing-dependent lncRNAs are expressed in reproductive tissues. These results show that lncRNAs are key components intervening in S. mansoni adult worm homeostasis, which affects pairing status and survival in the mammalian host, thus presenting great potential as new therapeutic target candidates.
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Affiliation(s)
- Gilbert O Silveira
- Laboratório de Ciclo Celular, Instituto Butantan, São Paulo, São Paulo, Brazil
- Instituto de Química, Universidade de São Paulo, São Paulo, São Paulo, Brazil
| | - Helena S Coelho
- Laboratório de Ciclo Celular, Instituto Butantan, São Paulo, São Paulo, Brazil
| | - Adriana S A Pereira
- Laboratório de Ciclo Celular, Instituto Butantan, São Paulo, São Paulo, Brazil
- Instituto de Química, Universidade de São Paulo, São Paulo, São Paulo, Brazil
| | - Patrícia A Miyasato
- Laboratório de Parasitologia, Instituto Butantan, São Paulo, São Paulo, Brazil
| | - Daisy W Santos
- Laboratório de Ciclo Celular, Instituto Butantan, São Paulo, São Paulo, Brazil
- Instituto de Química, Universidade de São Paulo, São Paulo, São Paulo, Brazil
| | - Lucas F Maciel
- Laboratório de Ciclo Celular, Instituto Butantan, São Paulo, São Paulo, Brazil
| | - Giovanna G G Olberg
- Laboratório de Ciclo Celular, Instituto Butantan, São Paulo, São Paulo, Brazil
| | - Ana C Tahira
- Laboratório de Ciclo Celular, Instituto Butantan, São Paulo, São Paulo, Brazil
| | - Eliana Nakano
- Laboratório de Parasitologia, Instituto Butantan, São Paulo, São Paulo, Brazil
| | | | - Murilo S Amaral
- Laboratório de Ciclo Celular, Instituto Butantan, São Paulo, São Paulo, Brazil
| | - Sergio Verjovski-Almeida
- Laboratório de Ciclo Celular, Instituto Butantan, São Paulo, São Paulo, Brazil
- Instituto de Química, Universidade de São Paulo, São Paulo, São Paulo, Brazil
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3
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Ravaynia PS, Biendl S, Grassi F, Keiser J, Hierlemann A, Modena MM. Real-time and automated monitoring of antischistosomal drug activity profiles for screening of compound libraries. iScience 2022; 25:104087. [PMID: 35378863 PMCID: PMC8976133 DOI: 10.1016/j.isci.2022.104087] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/08/2021] [Revised: 02/02/2022] [Accepted: 03/14/2022] [Indexed: 11/26/2022] Open
Abstract
Schistosomiasis is a neglected tropical disease that affects over 200 million people annually. As the antischistosomal drug pipeline is currently empty, repurposing of compound libraries has become a source for accelerating drug development, which demands the implementation of high-throughput and efficient screening strategies. Here, we present a parallelized impedance-based platform for continuous and automated viability evaluation of Schistosoma mansoni schistosomula in 128 microwells during 72 h to identify antischistosomal hits in vitro. By initially screening 57 repurposed compounds against larvae, five drugs are identified, which reduce parasite viability by more than 70%. The activity profiles of the selected drugs are then investigated via real-time dose-response monitoring, and four compounds reveal high potency and rapid action, which renders them suitable candidates for follow-up tests against adult parasites. The study shows that our device is a reliable tool for real-time drug screening analysis of libraries to identify new promising therapeutics against schistosomiasis. Scalable, plastic microwell chip with integrated platinum electrodes Automated impedance-based recording of 128 microwell units in parallel Continuous monitoring of in vitro drug library efficacy on schistosomula for 72 h Identification of four fast-acting antischistosomal drugs for in vivo testing
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Affiliation(s)
- Paolo S Ravaynia
- Bioengineering Laboratory, Department of Biosystems Science and Engineering, ETH Zürich, Mattenstrasse 26, 4058 Basel, Switzerland
| | - Stefan Biendl
- Swiss Tropical and Public Health Institute, Department of Medical Parasitology and Infection Biology, University of Basel, Socinstrasse 57, 4051 Basel, Switzerland
| | - Francesco Grassi
- Centre for Microsystems Technology, Department of Electronics and Information Systems, Ghent University, Technologiepark-Zwijnaarde 126, 9052 Gent, Belgium
| | - Jennifer Keiser
- Swiss Tropical and Public Health Institute, Department of Medical Parasitology and Infection Biology, University of Basel, Socinstrasse 57, 4051 Basel, Switzerland
| | - Andreas Hierlemann
- Bioengineering Laboratory, Department of Biosystems Science and Engineering, ETH Zürich, Mattenstrasse 26, 4058 Basel, Switzerland
| | - Mario M Modena
- Bioengineering Laboratory, Department of Biosystems Science and Engineering, ETH Zürich, Mattenstrasse 26, 4058 Basel, Switzerland
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4
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Ghazy E, Abdelsalam M, Robaa D, Pierce RJ, Sippl W. Histone Deacetylase (HDAC) Inhibitors for the Treatment of Schistosomiasis. Pharmaceuticals (Basel) 2022; 15:ph15010080. [PMID: 35056137 PMCID: PMC8779837 DOI: 10.3390/ph15010080] [Citation(s) in RCA: 4] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/20/2021] [Revised: 01/06/2022] [Accepted: 01/08/2022] [Indexed: 12/18/2022] Open
Abstract
Schistosomiasis is a major neglected parasitic disease that affects more than 240 million people worldwide and for which the control strategy consists of mass treatment with the only available drug, praziquantel. Schistosomes display morphologically distinct stages during their life cycle and the transformations between stages are controlled by epigenetic mechanisms. The targeting of epigenetic actors might therefore represent the parasites’ Achilles’ heel. Specifically, histone deacetylases have been recently characterized as drug targets for the treatment of schistosomiasis. This review focuses on the recent development of inhibitors for schistosome histone deacetylases. In particular, advances in the development of inhibitors of Schistosoma mansoni histone deacetylase 8 have indicated that targeting this enzyme is a promising approach for the treatment of this infection.
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Affiliation(s)
- Ehab Ghazy
- Department of Medicinal Chemistry, Institute of Pharmacy, Martin-Luther-University of Halle-Wittenberg, 06120 Halle (Saale), Germany; (E.G.); (M.A.); (D.R.)
- Department of Pharmaceutical Chemistry, Faculty of Pharmacy, Alexandria University, Alexandria 21521, Egypt
| | - Mohamed Abdelsalam
- Department of Medicinal Chemistry, Institute of Pharmacy, Martin-Luther-University of Halle-Wittenberg, 06120 Halle (Saale), Germany; (E.G.); (M.A.); (D.R.)
- Department of Pharmaceutical Chemistry, Faculty of Pharmacy, Alexandria University, Alexandria 21521, Egypt
| | - Dina Robaa
- Department of Medicinal Chemistry, Institute of Pharmacy, Martin-Luther-University of Halle-Wittenberg, 06120 Halle (Saale), Germany; (E.G.); (M.A.); (D.R.)
| | - Raymond J. Pierce
- Centre d’Infection et d’Immunité de Lille, U1019—UMR9017—CIIL, Institute Pasteur de Lille, CNRS, Inserm, CHU Lille, Univ. Lille, F-59000 Lille, France;
| | - Wolfgang Sippl
- Department of Medicinal Chemistry, Institute of Pharmacy, Martin-Luther-University of Halle-Wittenberg, 06120 Halle (Saale), Germany; (E.G.); (M.A.); (D.R.)
- Correspondence:
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5
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Moreira-Filho JT, Silva AC, Dantas RF, Gomes BF, Souza Neto LR, Brandao-Neto J, Owens RJ, Furnham N, Neves BJ, Silva-Junior FP, Andrade CH. Schistosomiasis Drug Discovery in the Era of Automation and Artificial Intelligence. Front Immunol 2021; 12:642383. [PMID: 34135888 PMCID: PMC8203334 DOI: 10.3389/fimmu.2021.642383] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/15/2020] [Accepted: 04/30/2021] [Indexed: 12/20/2022] Open
Abstract
Schistosomiasis is a parasitic disease caused by trematode worms of the genus Schistosoma and affects over 200 million people worldwide. The control and treatment of this neglected tropical disease is based on a single drug, praziquantel, which raises concerns about the development of drug resistance. This, and the lack of efficacy of praziquantel against juvenile worms, highlights the urgency for new antischistosomal therapies. In this review we focus on innovative approaches to the identification of antischistosomal drug candidates, including the use of automated assays, fragment-based screening, computer-aided and artificial intelligence-based computational methods. We highlight the current developments that may contribute to optimizing research outputs and lead to more effective drugs for this highly prevalent disease, in a more cost-effective drug discovery endeavor.
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Affiliation(s)
- José T. Moreira-Filho
- LabMol – Laboratory for Molecular Modeling and Drug Design, Faculdade de Farmácia, Universidade Federal de Goiás – UFG, Goiânia, Brazil
| | - Arthur C. Silva
- LabMol – Laboratory for Molecular Modeling and Drug Design, Faculdade de Farmácia, Universidade Federal de Goiás – UFG, Goiânia, Brazil
| | - Rafael F. Dantas
- LaBECFar – Laboratório de Bioquímica Experimental e Computacional de Fármacos, Instituto Oswaldo Cruz, Fundação Oswaldo Cruz, Rio de Janeiro, Brazil
| | - Barbara F. Gomes
- LaBECFar – Laboratório de Bioquímica Experimental e Computacional de Fármacos, Instituto Oswaldo Cruz, Fundação Oswaldo Cruz, Rio de Janeiro, Brazil
| | - Lauro R. Souza Neto
- LaBECFar – Laboratório de Bioquímica Experimental e Computacional de Fármacos, Instituto Oswaldo Cruz, Fundação Oswaldo Cruz, Rio de Janeiro, Brazil
| | - Jose Brandao-Neto
- Diamond Light Source Ltd., Didcot, United Kingdom
- Research Complex at Harwell, Didcot, United Kingdom
| | - Raymond J. Owens
- The Rosalind Franklin Institute, Harwell, United Kingdom
- Division of Structural Biology, The Wellcome Centre for Human Genetic, University of Oxford, Oxford, United Kingdom
| | - Nicholas Furnham
- Department of Infection Biology, Faculty of Infectious and Tropical Diseases, London School of Hygiene and Tropical Medicine, London, United Kingdom
| | - Bruno J. Neves
- LabMol – Laboratory for Molecular Modeling and Drug Design, Faculdade de Farmácia, Universidade Federal de Goiás – UFG, Goiânia, Brazil
| | - Floriano P. Silva-Junior
- LaBECFar – Laboratório de Bioquímica Experimental e Computacional de Fármacos, Instituto Oswaldo Cruz, Fundação Oswaldo Cruz, Rio de Janeiro, Brazil
| | - Carolina H. Andrade
- LabMol – Laboratory for Molecular Modeling and Drug Design, Faculdade de Farmácia, Universidade Federal de Goiás – UFG, Goiânia, Brazil
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Vejzagić N, Prodjinotho UF, El-Khafif N, Huang R, Simeonov A, Spangenberg T, Prazeres da Costa C. Identification of hit compounds with anti-schistosomal activity on in vitro generated juvenile worms in cell-free medium. PLoS Negl Trop Dis 2021; 15:e0009432. [PMID: 34033658 PMCID: PMC8191877 DOI: 10.1371/journal.pntd.0009432] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/23/2020] [Revised: 06/10/2021] [Accepted: 05/01/2021] [Indexed: 11/30/2022] Open
Abstract
Background Anthelminthic treatment options against schistosomiasis are limited. The current treatment relies almost exclusively on a single drug, praziquantel (PZQ). As a consequence, the development of resistance to PZQ and limited activity of PZQ against earlier development stages are respectively a risk and a limitation to achieving the goals of the new WHO roadmap towards elimination. For the discovery of new chemical starting points, the in vitro drug screening on Schistosoma mansoni (S. mansoni) against newly transformed schistosomula (NTS) is still the most predominant approach. The use of only NTS in the initial screening limits sensitivity to potential new compounds which are predominantly active in later developmental stages. Using our recently described highly standardized, straightforward and reliable culture method that generates high rates of juvenile worms, we aimed to repurpose a subset of the National Center for Advancing Translational Sciences (NCATS) Pharmaceutical Collection (340 compounds) to identify new hits with an in vitro worm culture assay. Methodology/Principal findings Cercariae were mechanically transformed into skin-stage (SkS) schistosomula and continuously cultured for 3–6 weeks to the liver stage (LiS). A commercial source of serum was identified, and decrease of NTS/well along with optimal drug testing conditions was established to test compounds on early and late LiS worms. The library was screened in 96-well format assays using praziquantel (PZQ) as a positive control. Primary screening allowed a 5.9% hit rate and generated two confirmed hits on adult worms; a prophylactic antianginal agent and an antihistaminic drug. Conclusion With this standardized and reliable in vitro assay, important S. mansoni developmental stages up to LiS worms can be generated and cultured over an extended period. When exposed to a subset of the NCATS Pharmaceutical Collection, 3 compounds yielded a defined anti-schistosomal phenotype on juvenile worms. Translation of activity on perfused adult S. mansoni worms was achieved only for perhexiline (a prophylactic antianginal agent) and astemizole (an antihistaminic drug). Schistosomiasis continues to be a major public health problem, mainly in developing countries. Although there have been some advances in finding new drugs, praziquantel is still the drug of choice. Certainly, one of the most important advances in the search for new treatments was the ability to in vitro transform cercariae and to grow schistosomula in culture. To reduce animal use in future drug discovery efforts (3Rs), we optimized a previously established reliable and robust in vitro cell-free culture system for the generation of liver-stage worms that we applied to the screening of a compound library stemming from the National Center for Advancing Translational Sciences (NCATS) Pharmaceutical Collection.
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Affiliation(s)
- Nermina Vejzagić
- Institute for Microbiology, Immunology and Hygiene, Technische Universität München, Munich, Germany
- Center for Global Health, TUM School of Medicine, Technische Universität München, Munich, Germany
| | - Ulrich Fabien Prodjinotho
- Institute for Microbiology, Immunology and Hygiene, Technische Universität München, Munich, Germany
- Center for Global Health, TUM School of Medicine, Technische Universität München, Munich, Germany
| | - Nagwa El-Khafif
- Theodor Bilharz Research Institute, Mahad Al Abhas Al Bahari, Warraq Al Arab, El Warraq, Giza Governorate, Egypt
| | - Ruili Huang
- Division of Pre-clinical Innovation, National Center for Advancing Translational Sciences, National Institutes of Health, Rockville, Maryland, United States of America
| | - Anton Simeonov
- Division of Pre-clinical Innovation, National Center for Advancing Translational Sciences, National Institutes of Health, Rockville, Maryland, United States of America
| | - Thomas Spangenberg
- Global Health Institute of Merck, Ares Trading S.A. (a subsidiary of Merck KGaA Darmstadt Germany), Eysins, Switzerland
| | - Clarissa Prazeres da Costa
- Institute for Microbiology, Immunology and Hygiene, Technische Universität München, Munich, Germany
- Center for Global Health, TUM School of Medicine, Technische Universität München, Munich, Germany
- * E-mail:
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7
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Zorn KM, Sun S, McConnon CL, Ma K, Chen EK, Foil DH, Lane TR, Liu LJ, El-Sakkary N, Skinner DE, Ekins S, Caffrey CR. A Machine Learning Strategy for Drug Discovery Identifies Anti-Schistosomal Small Molecules. ACS Infect Dis 2021; 7:406-420. [PMID: 33434015 PMCID: PMC7887754 DOI: 10.1021/acsinfecdis.0c00754] [Citation(s) in RCA: 12] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/08/2023]
Abstract
![]()
Schistosomiasis is a chronic and
painful disease of poverty caused
by the flatworm parasite Schistosoma. Drug discovery
for antischistosomal compounds predominantly employs in vitro whole organism (phenotypic) screens against two developmental stages
of Schistosoma mansoni, post-infective larvae (somules)
and adults. We generated two rule books and associated scoring systems
to normalize 3898 phenotypic data points to enable machine learning.
The data were used to generate eight Bayesian machine learning models
with the Assay Central software according to parasite’s developmental
stage and experimental time point (≤24, 48, 72, and >72
h).
The models helped predict 56 active and nonactive compounds from commercial
compound libraries for testing. When these were screened against S. mansoni in vitro, the prediction accuracy for active
and inactives was 61% and 56% for somules and adults, respectively;
also, hit rates were 48% and 34%, respectively, far exceeding the
typical 1–2% hit rate for traditional high throughput screens.
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Affiliation(s)
- Kimberley M. Zorn
- Collaborations Pharmaceuticals, 840 Main Campus Drive, Lab 3510, Raleigh, North Carolina 27606, United States
| | - Shengxi Sun
- Center for Discovery and Innovation in Parasitic Diseases, Skaggs School of Pharmacy and Pharmaceutical Sciences, University of California, San Diego, La Jolla, California 92093-0021, United States
| | - Cecelia L. McConnon
- Center for Discovery and Innovation in Parasitic Diseases, Skaggs School of Pharmacy and Pharmaceutical Sciences, University of California, San Diego, La Jolla, California 92093-0021, United States
| | - Kelley Ma
- Center for Discovery and Innovation in Parasitic Diseases, Skaggs School of Pharmacy and Pharmaceutical Sciences, University of California, San Diego, La Jolla, California 92093-0021, United States
| | - Eric K. Chen
- Center for Discovery and Innovation in Parasitic Diseases, Skaggs School of Pharmacy and Pharmaceutical Sciences, University of California, San Diego, La Jolla, California 92093-0021, United States
| | - Daniel H. Foil
- Collaborations Pharmaceuticals, 840 Main Campus Drive, Lab 3510, Raleigh, North Carolina 27606, United States
| | - Thomas R. Lane
- Collaborations Pharmaceuticals, 840 Main Campus Drive, Lab 3510, Raleigh, North Carolina 27606, United States
| | - Lawrence J. Liu
- Center for Discovery and Innovation in Parasitic Diseases, Skaggs School of Pharmacy and Pharmaceutical Sciences, University of California, San Diego, La Jolla, California 92093-0021, United States
| | - Nelly El-Sakkary
- Center for Discovery and Innovation in Parasitic Diseases, Skaggs School of Pharmacy and Pharmaceutical Sciences, University of California, San Diego, La Jolla, California 92093-0021, United States
| | - Danielle E. Skinner
- Center for Discovery and Innovation in Parasitic Diseases, Skaggs School of Pharmacy and Pharmaceutical Sciences, University of California, San Diego, La Jolla, California 92093-0021, United States
| | - Sean Ekins
- Collaborations Pharmaceuticals, 840 Main Campus Drive, Lab 3510, Raleigh, North Carolina 27606, United States
| | - Conor R. Caffrey
- Center for Discovery and Innovation in Parasitic Diseases, Skaggs School of Pharmacy and Pharmaceutical Sciences, University of California, San Diego, La Jolla, California 92093-0021, United States
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8
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Chen S, Suzuki BM, Dohrmann J, Singh R, Arkin MR, Caffrey CR. A multi-dimensional, time-lapse, high content screening platform applied to schistosomiasis drug discovery. Commun Biol 2020; 3:747. [PMID: 33349640 PMCID: PMC7752906 DOI: 10.1038/s42003-020-01402-5] [Citation(s) in RCA: 11] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/18/2020] [Accepted: 10/02/2020] [Indexed: 12/29/2022] Open
Abstract
Approximately 10% of the world's population is at risk of schistosomiasis, a disease of poverty caused by the Schistosoma parasite. To facilitate drug discovery for this complex flatworm, we developed an automated high-content screen to quantify the multidimensional responses of Schistosoma mansoni post-infective larvae (somules) to chemical insult. We describe an integrated platform to process worms at scale, collect time-lapsed, bright-field images, segment highly variable and touching worms, and then store, visualize, and query dynamic phenotypes. To demonstrate the methodology, we treated somules with seven drugs that generated diverse responses and evaluated 45 static and kinetic response descriptors relative to concentration and time. For compound screening, we used the Mahalanobis distance to compare multidimensional phenotypic effects induced by 1323 approved drugs. Overall, we characterize both known anti-schistosomals and identify new bioactives. Apart from facilitating drug discovery, the multidimensional quantification provided by this platform will allow mapping of chemistry to phenotype.
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Affiliation(s)
- Steven Chen
- Department of Pharmaceutical Chemistry and Small Molecule Discovery Center, University of California, San Francisco, CA, 94143, USA
| | - Brian M Suzuki
- Center for Discovery and Innovation in Parasitic Diseases, Department of Pathology, University of California, San Francisco, CA, 94158, USA
- Center for Discovery and Innovation in Parasitic Diseases, Skaggs School of Pharmacy and Pharmaceutical Sciences, University of California, San Diego, La Jolla, CA, 92093, USA
| | - Jakob Dohrmann
- Department of Computer Science, San Francisco State University, San Francisco, CA, 94132, USA
| | - Rahul Singh
- Department of Computer Science, San Francisco State University, San Francisco, CA, 94132, USA.
| | - Michelle R Arkin
- Department of Pharmaceutical Chemistry and Small Molecule Discovery Center, University of California, San Francisco, CA, 94143, USA.
| | - Conor R Caffrey
- Center for Discovery and Innovation in Parasitic Diseases, Department of Pathology, University of California, San Francisco, CA, 94158, USA.
- Center for Discovery and Innovation in Parasitic Diseases, Skaggs School of Pharmacy and Pharmaceutical Sciences, University of California, San Diego, La Jolla, CA, 92093, USA.
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9
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Long non-coding RNA levels can be modulated by 5-azacytidine in Schistosoma mansoni. Sci Rep 2020; 10:21565. [PMID: 33299037 PMCID: PMC7725772 DOI: 10.1038/s41598-020-78669-5] [Citation(s) in RCA: 8] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/27/2020] [Accepted: 11/27/2020] [Indexed: 02/06/2023] Open
Abstract
Schistosoma mansoni is a flatworm that causes schistosomiasis, a neglected tropical disease that affects more than 200 million people worldwide. There is only one drug indicated for treatment, praziquantel, which may lead to parasite resistance emergence. The ribonucleoside analogue 5-azacytidine (5-AzaC) is an epigenetic drug that inhibits S. mansoni oviposition and ovarian development through interference with parasite transcription, translation and stem cell activities. Therefore, studying the downstream pathways affected by 5-AzaC in S. mansoni may contribute to the discovery of new drug targets. Long non-coding RNAs (lncRNAs) are transcripts longer than 200 nucleotides with low or no protein coding potential that have been involved in reproduction, stem cell maintenance and drug resistance. We have recently published a catalog of lncRNAs expressed in S. mansoni life-cycle stages, tissues and single cells. However, it remains largely unknown if lncRNAs are responsive to epigenetic drugs in parasites. Here, we show by RNA-Seq re-analyses that hundreds of lncRNAs are differentially expressed after in vitro 5-AzaC treatment of S. mansoni females, including intergenic, antisense and sense lncRNAs. Many of these lncRNAs belong to co-expression network modules related to male metabolism and are also differentially expressed in unpaired compared with paired females and ovaries. Half of these lncRNAs possess histone marks at their genomic loci, indicating regulation by histone modification. Among a selected set of 8 lncRNAs, half of them were validated by RT-qPCR as differentially expressed in females, and some of them also in males. Interestingly, these lncRNAs are also expressed in other life-cycle stages. This study demonstrates that many lncRNAs potentially involved with S. mansoni reproductive biology are modulated by 5-AzaC and sheds light on the relevance of exploring lncRNAs in response to drug treatments in parasites.
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10
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Coutinho Carneiro V, de Abreu da Silva IC, Amaral MS, Pereira ASA, Silveira GO, Pires DDS, Verjovski-Almeida S, Dekker FJ, Rotili D, Mai A, Lopes-Torres EJ, Robaa D, Sippl W, Pierce RJ, Borrello MT, Ganesan A, Lancelot J, Thiengo S, Fernandez MA, Vicentino ARR, Mourão MM, Coelho FS, Fantappié MR. Pharmacological inhibition of lysine-specific demethylase 1 (LSD1) induces global transcriptional deregulation and ultrastructural alterations that impair viability in Schistosoma mansoni. PLoS Negl Trop Dis 2020; 14:e0008332. [PMID: 32609727 PMCID: PMC7329083 DOI: 10.1371/journal.pntd.0008332] [Citation(s) in RCA: 8] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/08/2019] [Accepted: 04/28/2020] [Indexed: 02/06/2023] Open
Abstract
Treatment and control of schistosomiasis still rely on only one effective drug, praziquantel (PZQ) and, due to mass treatment, the increasing risk of selecting for schistosome strains that are resistant to PZQ has alerted investigators to the urgent need to develop novel therapeutic strategies. The histone-modifying enzymes (HMEs) represent promising targets for the development of epigenetic drugs against Schistosoma mansoni. In the present study, we targeted the S. mansoni lysine-specific demethylase 1 (SmLSD1), a transcriptional corepressor, using a novel and selective synthetic inhibitor, MC3935, which was used to treat schistosomula and adult worms in vitro. By using cell viability assays and optical and electron microscopy, we showed that treatment with MC3935 affected parasite motility, egg-laying, tegument, and cellular organelle structures, culminating in the death of schistosomula and adult worms. In silico molecular modeling and docking analysis suggested that MC3935 binds to the catalytic pocket of SmLSD1. Western blot analysis revealed that MC3935 inhibited SmLSD1 demethylation activity of H3K4me1/2. Knockdown of SmLSD1 by RNAi recapitulated MC3935 phenotypes in adult worms. RNA-Seq analysis of MC3935-treated parasites revealed significant differences in gene expression related to critical biological processes. Collectively, our findings show that SmLSD1 is a promising drug target for the treatment of schistosomiasis and strongly support the further development and in vivo testing of selective schistosome LSD1 inhibitors.
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Affiliation(s)
- Vitor Coutinho Carneiro
- Instituto de Bioquímica Médica Leopoldo de Meis, Programa de Biologia Molecular e Biotecnologia, Centro de Ciências da Saúde, Universidade Federal do Rio de Janeiro, Rio de Janeiro, Brazil
| | - Isabel Caetano de Abreu da Silva
- Instituto de Bioquímica Médica Leopoldo de Meis, Programa de Biologia Molecular e Biotecnologia, Centro de Ciências da Saúde, Universidade Federal do Rio de Janeiro, Rio de Janeiro, Brazil
| | | | - Adriana S. A. Pereira
- Laboratório de Parasitologia, Instituto Butantan, São Paulo, Brazil
- Departamento de Bioquímica, Instituto de Química, Universidade de São Paulo, São Paulo, Brasil
| | - Gilbert Oliveira Silveira
- Laboratório de Parasitologia, Instituto Butantan, São Paulo, Brazil
- Departamento de Bioquímica, Instituto de Química, Universidade de São Paulo, São Paulo, Brasil
| | | | - Sergio Verjovski-Almeida
- Laboratório de Parasitologia, Instituto Butantan, São Paulo, Brazil
- Departamento de Bioquímica, Instituto de Química, Universidade de São Paulo, São Paulo, Brasil
| | - Frank J. Dekker
- Department of Chemical and Pharmaceutical Biology, University of Groningen, Antonius Deusinglaan, AV Groningen, Netherlands
| | - Dante Rotili
- Department of Drug Chemistry and Technologies, Sapienza University of Rome, Rome, Italy
| | - Antonello Mai
- Department of Drug Chemistry and Technologies, Sapienza University of Rome, Rome, Italy
| | - Eduardo José Lopes-Torres
- Laboratório de Helmintologia Romero Lascasas Porto, Faculdade de Ciências Médicas, Universidade do Estado do Rio de Janeiro, Rio de Janeiro, Brazil
| | - Dina Robaa
- Institute of Pharmacy, Martin Luther University of Halle-Wittenberg, Germany
| | - Wolfgang Sippl
- Institute of Pharmacy, Martin Luther University of Halle-Wittenberg, Germany
| | - Raymond J. Pierce
- Université de Lille, CNRS, Inserm, CHU Lille, Institut Pasteur de Lille, U1019—UMR 9017—CIIL—Centre d’Infection et d’Immunité de Lille, Lille, France
| | - M. Teresa Borrello
- Centre de Recherche en Cancérologie de Marseille (CRCM), INSERM U1068, CNRS UMR 7258, Aix-Marseille Université and Institut Paoli-Calmettes, Parc Scientifique et Technologique de Luminy, Marseille, France
| | - A. Ganesan
- School of Pharmacy, University of East Anglia, Norwich NR4 7TJ, United Kingdom
| | - Julien Lancelot
- Université de Lille, CNRS, Inserm, CHU Lille, Institut Pasteur de Lille, U1019—UMR 9017—CIIL—Centre d’Infection et d’Immunité de Lille, Lille, France
| | - Silvana Thiengo
- Laboratório de Malacologia, Fundação Oswaldo Cruz, Instituto Oswaldo Cruz, Rio de Janeiro, Brazil
| | - Monica Ammon Fernandez
- Laboratório de Malacologia, Fundação Oswaldo Cruz, Instituto Oswaldo Cruz, Rio de Janeiro, Brazil
| | - Amanda Roberta Revoredo Vicentino
- Instituto de Bioquímica Médica Leopoldo de Meis, Programa de Biologia Molecular e Biotecnologia, Centro de Ciências da Saúde, Universidade Federal do Rio de Janeiro, Rio de Janeiro, Brazil
| | - Marina Moraes Mourão
- Grupo de Helmintologia e Malacologia Médica, Instituto René Rachou, Fundação Oswaldo Cruz, Belo Horizonte, Brazil
| | - Fernanda Sales Coelho
- Grupo de Helmintologia e Malacologia Médica, Instituto René Rachou, Fundação Oswaldo Cruz, Belo Horizonte, Brazil
| | - Marcelo Rosado Fantappié
- Instituto de Bioquímica Médica Leopoldo de Meis, Programa de Biologia Molecular e Biotecnologia, Centro de Ciências da Saúde, Universidade Federal do Rio de Janeiro, Rio de Janeiro, Brazil
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11
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Duguet TB, Glebov A, Hussain A, Kulkarni S, Mochalkin I, Geary TG, Rashid M, Spangenberg T, Ribeiro P. Identification of annotated bioactive molecules that impair motility of the blood fluke Schistosoma mansoni. INTERNATIONAL JOURNAL FOR PARASITOLOGY-DRUGS AND DRUG RESISTANCE 2020; 13:73-88. [PMID: 32531750 PMCID: PMC7284125 DOI: 10.1016/j.ijpddr.2020.05.002] [Citation(s) in RCA: 8] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 01/24/2020] [Revised: 05/14/2020] [Accepted: 05/14/2020] [Indexed: 01/21/2023]
Abstract
Neglected tropical diseases are of growing worldwide concern and schistosomiasis, caused by parasitic flatworms, continues to be a major threat with more than 200 million people requiring preventive treatment. As praziquantel (PZQ) remains the treatment of choice, an urgent need for alternative treatments motivates research to identify new lead compounds that would complement PZQ by filling the therapeutic gaps associated with this treatment. Because impairing parasite neurotransmission remains a core strategy for control of parasitic helminths, we screened a library of 708 compounds with validated biological activity in humans on the blood fluke Schistosoma mansoni, measuring their effect on the motility on schistosomulae and adult worms. The primary phenotypic screen performed on schistosomulae identified 70 compounds that induced changes in viability and/or motility. Screening different concentrations and incubation times identified molecules with fast onset of activity on both life stages at low concentration (1 μM). To complement this study, similar assays were performed with chemical analogs of the cholinomimetic drug arecoline and the calcilytic molecule NPS-2143, two compounds that rapidly inhibited schistosome motility; 17 arecoline and 302 NPS-2143 analogs were tested to enlarge the pool of schistosomicidal molecules. Finally, validated hit compounds were tested on three functionally-validated neuroregulatory S. mansoni G-protein coupled receptors (GPCRs): Sm5HTR (serotonin-sensitive), SmGPR2 (histamine) and SmD2 (dopamine), revealing NPS-2143 and analogs as potent inhibitors of dopamine/epinine responses on both human and S. mansoni GPCRs. This study highlights the potential for repurposing known human therapeutic agents for potential schistosomicidal effects and expands the list of hits for further progression.
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Affiliation(s)
- Thomas B Duguet
- Institute of Parasitology, McGill University, Sainte-Anne-de-Bellevue, Quebec, Canada.
| | - Anastasia Glebov
- Institute of Parasitology, McGill University, Sainte-Anne-de-Bellevue, Quebec, Canada
| | - Asimah Hussain
- Institute of Parasitology, McGill University, Sainte-Anne-de-Bellevue, Quebec, Canada
| | | | - Igor Mochalkin
- EMD Serono Research and Development Institute, Billerica, MA, USA
| | - Timothy G Geary
- Institute of Parasitology, McGill University, Sainte-Anne-de-Bellevue, Quebec, Canada
| | - Mohammed Rashid
- Institute of Parasitology, McGill University, Sainte-Anne-de-Bellevue, Quebec, Canada
| | - Thomas Spangenberg
- Global Health Institute of Merck, Ares Trading S.A., a subsidiary of Merck KGaA (Darmstadt, Germany), Eysins, Switzerland.
| | - Paula Ribeiro
- Institute of Parasitology, McGill University, Sainte-Anne-de-Bellevue, Quebec, Canada
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12
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Lobo-Silva J, Cabral FJ, Amaral MS, Miyasato PA, de Freitas RP, Pereira ASA, Khouri MI, Barbosa MMF, Ramos PIP, Leite LCC, Asojo OA, Nakano E, Verjovski-Almeida S, Farias LP. The antischistosomal potential of GSK-J4, an H3K27 demethylase inhibitor: insights from molecular modeling, transcriptomics and in vitro assays. Parasit Vectors 2020; 13:140. [PMID: 32178714 PMCID: PMC7077139 DOI: 10.1186/s13071-020-4000-z] [Citation(s) in RCA: 13] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/25/2019] [Accepted: 02/26/2020] [Indexed: 12/20/2022] Open
Abstract
Background Schistosomiasis chemotherapy is largely based on praziquantel (PZQ). Although PZQ is very safe and tolerable, it does not prevent reinfection and emerging resistance is a primary concern. Recent studies have shown that the targeting of epigenetic machinery in Schistosoma mansoni may result in severe alterations in parasite development, leading to death. This new route for drug discovery in schistosomiasis has focused on classes of histone deacetylases (HDACs) and histone acetyltransferases (HATs) as epigenetic drug targets. Schistosoma histone demethylases also seem to be important in the transition of cercariae into schistosomula, as well as sexual differentiation in adult worms. Methods The Target-Pathogen database and molecular docking assays were used to prioritize the druggability of S. mansoni histone demethylases. The transcription profile of Smp_03400 was re-analyzed using available databases. The effect of GSK-J4 inhibitor in schistosomula and adult worms’ motility/viability/oviposition was assessed by in vitro assays. Ultrastructural analysis was performed on adult worms exposed to GSK-J4 by scanning electron microscopy, while internal structures and muscle fiber integrity was investigated by confocal microscopy after Langeronʼs carmine or phalloidin staining. Results The present evaluation of the potential druggability of 14 annotated S. mansoni demethylase enzymes identified the S. mansoni ortholog of human KDM6A/UTX (Smp_034000) as the most suitable druggable target. In silico analysis and molecular modeling indicated the potential for cofactor displacement by the chemical probe GSK-J4. Our re-analysis of transcriptomic data revealed that Smp_034000 expression peaks at 24 h in newly transformed schistosomula and 5-week-old adult worms. Moreover, this gene was highly expressed in the testes of mature male worms compared to the rest of the parasite body. In in vitro schistosome cultures, treatment with GSK-J4 produced striking effects on schistosomula mortality and adult worm motility and mortality, as well as egg oviposition, in a dose- and time-dependent manner. Unexpectedly, western blot assays did not demonstrate overall modulation of H3K27me3 levels in response to GSK-J4. Confocal and scanning electron microscopy revealed the loss of original features in muscle fibers and alterations in cell-cell contact following GSK-J4 treatment. Conclusions GSK-J4 presents promising potential for antischistosomal control; however, the underlying mechanisms warrant further investigation.![]()
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Affiliation(s)
- Jessica Lobo-Silva
- Laboratório de Biomarcadores e Inflamação, Instituto Gonçalo Moniz, Fundação Oswaldo Cruz, Salvador, Bahia, Brazil
| | - Fernanda J Cabral
- Departamento de Biologia Animal, Instituto de Biologia, Universidade Estadual de Campinas, Campinas, SP, Brazil
| | - Murilo S Amaral
- Laboratório de Expressão Gênica em Eucariotos, Instituto Butantan, São Paulo, SP, Brazil
| | | | | | - Adriana S A Pereira
- Laboratório de Expressão Gênica em Eucariotos, Instituto Butantan, São Paulo, SP, Brazil.,Departamento de Bioquímica, Instituto de Química, Universidade de São Paulo, São Paulo, Brazil
| | - Mariana I Khouri
- Laboratório de Biomarcadores e Inflamação, Instituto Gonçalo Moniz, Fundação Oswaldo Cruz, Salvador, Bahia, Brazil
| | - Mayra M F Barbosa
- Laboratório Especial de Desenvolvimento de Vacinas, Instituto Butantan, São Paulo, SP, Brazil
| | - Pablo I P Ramos
- Centro de Integração de Dados e Conhecimentos para Saúde (CIDACS), Instituto Gonçalo Moniz, Fundação Oswaldo Cruz, Salvador, Bahia, Brazil
| | - Luciana C C Leite
- Laboratório Especial de Desenvolvimento de Vacinas, Instituto Butantan, São Paulo, SP, Brazil
| | - Oluwatoyin A Asojo
- Department of Chemistry and Biochemistry, Hampton University, Hampton, VA, USA
| | - Eliana Nakano
- Laboratório de Parasitologia, Instituto Butantan, São Paulo, SP, Brazil
| | - Sergio Verjovski-Almeida
- Laboratório de Expressão Gênica em Eucariotos, Instituto Butantan, São Paulo, SP, Brazil.,Departamento de Bioquímica, Instituto de Química, Universidade de São Paulo, São Paulo, Brazil
| | - Leonardo P Farias
- Laboratório de Biomarcadores e Inflamação, Instituto Gonçalo Moniz, Fundação Oswaldo Cruz, Salvador, Bahia, Brazil.
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13
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Braun L, Hazell L, Webb AJ, Allan F, Emery AM, Templeton MR. Determining the viability of Schistosoma mansoni cercariae using fluorescence assays: An application for water treatment. PLoS Negl Trop Dis 2020; 14:e0008176. [PMID: 32214320 PMCID: PMC7138324 DOI: 10.1371/journal.pntd.0008176] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/11/2019] [Revised: 04/07/2020] [Accepted: 02/27/2020] [Indexed: 01/18/2023] Open
Abstract
BACKGROUND Schistosome cercariae are the human-infectious stage of the Schistosoma parasite. They are shed by snail intermediate hosts living in freshwater, and penetrate the skin of the human host to develop into schistosomes, resulting in schistosomiasis infection. Water treatment (e.g. filtration or chlorination) is one way of cutting disease transmission; it kills or removes cercariae to provide safe water for people to use for activities such as bathing or laundry as an alternative to infested lakes or rivers. At present, there is no standard method for assessing the effectiveness of water treatment processes on cercariae. Examining cercarial movement under a microscope is the most common method, yet it is subjective and time-consuming. Hence, there is a need to develop and verify accurate, high-throughput assays for quantifying cercarial viability. METHOD We tested two fluorescence assays for their ability to accurately determine cercarial viability in water samples, using S. mansoni cercariae released from infected snails in the Schistosomiasis Collection at the Natural History Museum, London. These assays consist of dual stains, namely a vital and non-vital dye; fluorescein diacetate (FDA) and Hoechst, and FDA and Propidium Iodide. We also compared the results of the fluorescence assays to the viability determined by microscopy. CONCLUSION Both fluorescence assays can detect the viability of cercariae to an accuracy of at least 92.2% ± 6.3%. Comparing the assays to microscopy, no statistically significant difference was found between the method's viability results. However, the fluorescence assays are less subjective and less time-consuming than microscopy, and therefore present a promising method for quantifying the viability of schistosome cercariae in water samples.
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Affiliation(s)
- Laura Braun
- Department of Civil and Environmental Engineering, Imperial College London, London, United Kingdom
| | - Lucinda Hazell
- Department of Civil and Environmental Engineering, Imperial College London, London, United Kingdom
| | - Alexander J Webb
- Section of Structural and Synthetic Biology, Department of Infectious Disease, Imperial College London, London, United Kingdom
| | - Fiona Allan
- Wolfson Wellcome Biomedical Laboratories, Department of Life Sciences, Natural History Museum, London, United Kingdom
| | - Aidan M Emery
- Wolfson Wellcome Biomedical Laboratories, Department of Life Sciences, Natural History Museum, London, United Kingdom
| | - Michael R Templeton
- Department of Civil and Environmental Engineering, Imperial College London, London, United Kingdom
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14
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Kalinin DV, Jana SK, Pfafenrot M, Chakrabarti A, Melesina J, Shaik TB, Lancelot J, Pierce RJ, Sippl W, Romier C, Jung M, Holl R. Structure-Based Design, Synthesis, and Biological Evaluation of Triazole-Based smHDAC8 Inhibitors. ChemMedChem 2020; 15:571-584. [PMID: 31816172 PMCID: PMC7187165 DOI: 10.1002/cmdc.201900583] [Citation(s) in RCA: 13] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/18/2019] [Indexed: 12/15/2022]
Abstract
Schistosomiasis is a neglected tropical disease caused by parasitic flatworms of the genus Schistosoma, which affects over 200 million people worldwide and leads to at least 300,000 deaths every year. In this study, initial screening revealed the triazole‐based hydroxamate 2 b (N‐hydroxy‐1‐phenyl‐1H‐1,2,3‐triazole‐4‐carboxamide) exhibiting potent inhibitory activity toward the novel antiparasitic target Schistosoma mansoni histone deacetylase 8 (smHDAC8) and promising selectivity over the major human HDACs. Subsequent crystallographic studies of the 2 b/smHDAC8 complex revealed key interactions between the inhibitor and the enzyme's active site, thus explaining the unique selectivity profile of the inhibitor. Further chemical modifications of 2 b led to the discovery of 4‐fluorophenoxy derivative 21 (1‐[5‐chloro‐2‐(4‐fluorophenoxy)phenyl]‐N‐hydroxy‐1H‐1,2,3‐triazole‐4‐carboxamide), a nanomolar smHDAC8 inhibitor (IC50=0.5 μM), exceeding the smHDAC8 inhibitory activity of 2 b and SAHA (vorinostat), while exhibiting an improved selectivity profile over the investigated human HDACs. Collectively, this study reveals specific interactions between smHDAC8 and the synthesized triazole‐based inhibitors and demonstrates that these small molecules represent promising lead structures, which could be further developed in the search for novel drugs for the treatment of schistosomiasis.
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Affiliation(s)
- Dmitrii V Kalinin
- Department of Chemistry Institute of Organic Chemistry, University of Hamburg, Martin-Luther-King-Platz 6, 20146, Hamburg, Germany.,German Center for Infection Research (DZIF) partner site Hamburg-Lübeck-Borstel-Riems.,Institute of Pharmaceutical and Medicinal Chemistry, University of Münster, Corrensstr. 48, 48149, Münster, Germany.,Cells-in-Motion Cluster of Excellence (EXC 1003 - CiM), University of Münster, Schlossplatz 4, 48149, Münster, Germany
| | - Sunit K Jana
- Institute of Pharmaceutical and Medicinal Chemistry, University of Münster, Corrensstr. 48, 48149, Münster, Germany.,NRW Graduate School of Chemistry, University of Münster, Wilhelm-Klemm-Str. 10, 48149, Münster, Germany
| | - Maxim Pfafenrot
- Institute of Pharmaceutical and Medicinal Chemistry, University of Münster, Corrensstr. 48, 48149, Münster, Germany
| | - Alokta Chakrabarti
- Institute of Pharmaceutical Sciences, Albert-Ludwigs-Universität Freiburg, Albertstr. 25, 79104, Freiburg, Germany
| | - Jelena Melesina
- Institute of Pharmacy, Martin Luther University of Halle-Wittenberg, Wolfgang-Langenbeck Str. 4, 06120, Halle/Saale, Germany
| | - Tajith B Shaik
- Département de Biologie Structurale Intégrative Institut de Génétique et Biologie Moléculaire et Cellulaire (IGBMC), Université de Strasbourg, CNRS, INSERM, 1 rue Laurent Fries, 67404, Illkirch Cedex, France
| | - Julien Lancelot
- Université de Lille, CNRS, Inserm, CHU Lille, Institut Pasteur de Lille U1019-UMR 8204-CIIL-Centre d'Infection et d'Immunité de Lille, 59000, Lille, France
| | - Raymond J Pierce
- Université de Lille, CNRS, Inserm, CHU Lille, Institut Pasteur de Lille U1019-UMR 8204-CIIL-Centre d'Infection et d'Immunité de Lille, 59000, Lille, France
| | - Wolfgang Sippl
- Institute of Pharmacy, Martin Luther University of Halle-Wittenberg, Wolfgang-Langenbeck Str. 4, 06120, Halle/Saale, Germany
| | - Christophe Romier
- Département de Biologie Structurale Intégrative Institut de Génétique et Biologie Moléculaire et Cellulaire (IGBMC), Université de Strasbourg, CNRS, INSERM, 1 rue Laurent Fries, 67404, Illkirch Cedex, France
| | - Manfred Jung
- Institute of Pharmaceutical Sciences, Albert-Ludwigs-Universität Freiburg, Albertstr. 25, 79104, Freiburg, Germany
| | - Ralph Holl
- Department of Chemistry Institute of Organic Chemistry, University of Hamburg, Martin-Luther-King-Platz 6, 20146, Hamburg, Germany.,German Center for Infection Research (DZIF) partner site Hamburg-Lübeck-Borstel-Riems
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15
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Pereira ASA, Silveira GO, Amaral MS, Almeida SMV, Oliveira JF, Lima MCA, Verjovski-Almeida S. In vitro activity of aryl-thiazole derivatives against Schistosoma mansoni schistosomula and adult worms. PLoS One 2019; 14:e0225425. [PMID: 31765429 PMCID: PMC6876889 DOI: 10.1371/journal.pone.0225425] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/26/2019] [Accepted: 11/05/2019] [Indexed: 12/30/2022] Open
Abstract
Schistosomiasis is caused by a trematode of the genus Schistosoma and affects over 200 million people worldwide. The only drug recommended by the World Health Organization for treatment and control of schistosomiasis is praziquantel. Development of new drugs is therefore of great importance. Thiazoles are regarded as privileged structures with a broad spectrum of activities and are potential sources of new drug prototypes, since they can act through interactions with DNA and inhibition of DNA synthesis. In this context, we report the synthesis of a series of thiazole derivatives and their in vitro schistosomicidal activity by testing eight molecules (NJ03-08; NJ11-12) containing thiazole structures. Parameters such as motility and mortality, egg laying, pairing and parasite viability by ATP quantification, which were influenced by these compounds, were evaluated during the assays. Scanning electron microscopy (SEM) was utilized for evaluation of morphological changes in the tegument. Schistosomula and adult worms were treated in vitro with different concentrations (6.25 to 50 μM) of the thiazoles for up to 5 and 3 days, respectively. After in vitro treatment for five days with 6.25 μM NJ05 or NJ07 separately, we observed a decrease of 30% in schistosomula viability, whilst treatment with NJ05+NJ07 lead to a reduction of 75% in viability measured by ATP quantitation and propidium iodide labeling. Adult worms’ treatment with 50 μM NJ05, NJ07 or NJ05 + NJ07 showed decreased motility to 30–50% compared with controls. Compound NJ05 was more effective than NJ07, and adult worm viability after three days was reduced to 25% in parasites treated with 50 μM NJ05, compared with a viability reduction to 40% with 50 μM NJ07. SEM analysis showed severe alterations in adult worms with formation of bulges and blisters throughout the dorsal region of parasites treated with NJ05 or NJ07. Oviposition was extremely affected by treatment with the NJ series compounds; at concentrations of 25 μM and 50 μM, oviposition reached almost zero with NJ05, NJ07 or NJ05 + NJ07 already at day one. Tested genes involved in egg biosynthesis were all confirmed by qPCR as downregulated in females treated with 25 μM NJ05 for 2 days, with a significant reduction in expression of p14, Tyrosinase 2, p48 and fs800. NJ05, NJ07 or NJ05+NJ07 treatment of HEK293 (human embryonic cell line) and HES (human epithelial cell line) showed EC50 in the range of 18.42 to 145.20 μM. Overall, our results demonstrate that those molecules are suitable targets for further development into new drugs for schistosomiasis treatment, although progress is needed to lessen the cytotoxic effects on human cells. According to the present study, thiazole derivatives have schistosomicidal activities and may be part of a possible new arsenal of compounds against schistosomiasis.
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Affiliation(s)
- Adriana S. A. Pereira
- Instituto Butantan, São Paulo, Brasil
- Departamento de Bioquímica, Instituto de Química, Universidade de São Paulo, São Paulo, Brasil
| | - Gilbert O. Silveira
- Instituto Butantan, São Paulo, Brasil
- Departamento de Bioquímica, Instituto de Química, Universidade de São Paulo, São Paulo, Brasil
| | | | - Sinara M. V. Almeida
- Universidade Federal de Pernambuco, Departamento de Antibióticos, Recife, Pernambuco, Brasil
- Universidade de Pernambuco, Campus Garanhuns, Garanhuns, Pernambuco, Brasil
| | - Jamerson F. Oliveira
- Universidade Federal de Pernambuco, Departamento de Antibióticos, Recife, Pernambuco, Brasil
| | - Maria C. A. Lima
- Universidade Federal de Pernambuco, Departamento de Antibióticos, Recife, Pernambuco, Brasil
| | - Sergio Verjovski-Almeida
- Instituto Butantan, São Paulo, Brasil
- Departamento de Bioquímica, Instituto de Química, Universidade de São Paulo, São Paulo, Brasil
- * E-mail:
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16
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Maccesi M, Aguiar PHN, Pasche V, Padilla M, Suzuki BM, Montefusco S, Abagyan R, Keiser J, Mourão MM, Caffrey CR. Multi-center screening of the Pathogen Box collection for schistosomiasis drug discovery. Parasit Vectors 2019; 12:493. [PMID: 31640761 PMCID: PMC6805474 DOI: 10.1186/s13071-019-3747-6] [Citation(s) in RCA: 16] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/12/2019] [Accepted: 10/11/2019] [Indexed: 12/24/2022] Open
Abstract
BACKGROUND Over the past five years, as a public service to encourage and accelerate drug discovery for diseases of poverty, the Medicines for Malaria Venture (MMV) has released box sets of 400 compounds named the Malaria, Pathogen and Stasis Boxes. Here, we screened the Pathogen Box against the post-infective larvae (schistosomula) of Schistosoma mansoni using assays particular to the three contributing institutions, namely, the University of California San Diego (UCSD) in the USA, the Swiss Tropical and Public Health Institute (Swiss TPH) in Switzerland, and the Fundação Oswaldo Cruz (FIOCRUZ) in Brazil. With the same set of compounds, the goal was to determine the degree of inter-assay variability and identify a core set of active compounds common to all three assays. New drugs for schistosomiasis would be welcome given that current treatment and control strategies rely on chemotherapy with just one drug, praziquantel. METHODS Both the UCSD and Swiss TPH assays utilize daily observational scoring methodologies over 72 h, whereas the FIOCRUZ assay employs XTT (2,3-bis(2-methoxy-4-nitro-5-sulfophenyl)-5-[(phenylamino)carbonyl]-2H-tetrazolium hydroxide) at 72 h to measure viability as a function of NAD+/NADH redox state. Raw and transformed data arising from each assay were assembled for comparative analysis. RESULTS For the UCSD and Swiss TPH assays, there was strong concordance of at least 87% in identifying active and inactive compounds on one or more of the three days. When all three assays were compared at 72 h, concordance remained a robust 74%. Further, robust Pearson's correlations (0.48-0.68) were measured between the assays. Of those actives at 72 h, the UCSD, Swiss TPH and FIOCRUZ assays identified 86, 103 and 66 compounds, respectively, of which 35 were common. Assay idiosyncrasies included the identification of unique compounds, the differential ability to identify known antischistosomal compounds and the concept that compounds of interest might include those that increase metabolic activity above baseline. CONCLUSIONS The inter-assay data generated were in good agreement, including with previously reported data. A common set of antischistosomal molecules for further exploration has been identified .
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Affiliation(s)
- Martina Maccesi
- Center for Discovery and Innovation in Parasitic Diseases, Skaggs School of Pharmacy and Pharmaceutical Sciences, University of California, San Diego, La Jolla, CA, USA
| | - Pedro H N Aguiar
- Laboratório de Helmintologia e Malacologia Médica, René Rachou Institute, FIOCRUZ, Belo Horizonte, Minas Gerais, Brazil
| | - Valérian Pasche
- Department of Medical Parasitology and Infection Biology, Swiss Tropical and Public Health Institute, P.O. Box, 4002, Basel, Switzerland.,University of Basel, P.O. Box, 4003, Basel, Switzerland
| | - Melody Padilla
- Center for Discovery and Innovation in Parasitic Diseases, Skaggs School of Pharmacy and Pharmaceutical Sciences, University of California, San Diego, La Jolla, CA, USA
| | - Brian M Suzuki
- Center for Discovery and Innovation in Parasitic Diseases, Skaggs School of Pharmacy and Pharmaceutical Sciences, University of California, San Diego, La Jolla, CA, USA
| | - Sandro Montefusco
- Center for Discovery and Innovation in Parasitic Diseases, Skaggs School of Pharmacy and Pharmaceutical Sciences, University of California, San Diego, La Jolla, CA, USA.,Telethon Institute of Genetics and Medicine (TIGEM), Pozzuoli, NA, Italy
| | - Ruben Abagyan
- Center for Discovery and Innovation in Parasitic Diseases, Skaggs School of Pharmacy and Pharmaceutical Sciences, University of California, San Diego, La Jolla, CA, USA
| | - Jennifer Keiser
- Department of Medical Parasitology and Infection Biology, Swiss Tropical and Public Health Institute, P.O. Box, 4002, Basel, Switzerland. .,University of Basel, P.O. Box, 4003, Basel, Switzerland.
| | - Marina M Mourão
- Laboratório de Helmintologia e Malacologia Médica, René Rachou Institute, FIOCRUZ, Belo Horizonte, Minas Gerais, Brazil.
| | - Conor R Caffrey
- Center for Discovery and Innovation in Parasitic Diseases, Skaggs School of Pharmacy and Pharmaceutical Sciences, University of California, San Diego, La Jolla, CA, USA.
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17
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Morales-Serna FN, Caña-Bozada VH, López-Moreno DG, Medina-Guerrero RM, Morales-Serna JA, Fajer-Ávila EJ. In vitro efficacy of two terpenes against ancyrocephalid monogeneans from Nile tilapia. J Parasit Dis 2019; 43:739-742. [PMID: 31749549 DOI: 10.1007/s12639-019-01150-2] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/02/2019] [Accepted: 08/11/2019] [Indexed: 12/01/2022] Open
Abstract
Terpenes are naturally produced compounds with a broad range of biological activities. Currently, there is limited information regarding the anthelminthic effect of terpenes against monogenean parasites of fish. The aim of this work was to evaluate the in vitro efficacy of two terpenes [α-terpinene and (+)-limonene oxide] against ancyrocephalid monogeneans found on farmed Nile tilapia (Oreochromis niloticus). (+)-Limonene oxide was more effective in killing these parasites than α-terpinene, with 86 and 90% mortality at concentrations of 36 and 55.4 mg/L, respectively, with a 5-h treatment. The estimated 5-h EC50 of (+)-limonene oxide was 4.8 mg/L. Even though this compound has the potential to be used as an anthelmintic compound in finfish aquaculture, before in vivo experiments are performed, additional studies are needed to find a more effective concentration, as well as to evaluate other terpenic compounds.
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Affiliation(s)
- Francisco N Morales-Serna
- 1CONACYT, Centro de Investigación en Alimentación y Desarrollo, A.C. Unidad Mazatlán en Acuicultura y Manejo Ambiental, 82112 Mazatlán, Sinaloa Mexico
| | - Víctor H Caña-Bozada
- 2Centro de Investigación en Alimentación y Desarrollo, A.C. Unidad Mazatlán en Acuicultura y Manejo Ambiental, 82112 Mazatlán, Sinaloa Mexico
| | - Dania G López-Moreno
- 2Centro de Investigación en Alimentación y Desarrollo, A.C. Unidad Mazatlán en Acuicultura y Manejo Ambiental, 82112 Mazatlán, Sinaloa Mexico
| | - Rosa M Medina-Guerrero
- 2Centro de Investigación en Alimentación y Desarrollo, A.C. Unidad Mazatlán en Acuicultura y Manejo Ambiental, 82112 Mazatlán, Sinaloa Mexico
| | - José A Morales-Serna
- 3Instituto de Química Aplicada, Universidad del Papaloapan, Tuxtepec, Oaxaca Mexico
| | - Emma J Fajer-Ávila
- 2Centro de Investigación en Alimentación y Desarrollo, A.C. Unidad Mazatlán en Acuicultura y Manejo Ambiental, 82112 Mazatlán, Sinaloa Mexico
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18
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Caffrey CR, El‐Sakkary N, Mäder P, Krieg R, Becker K, Schlitzer M, Drewry DH, Vennerstrom JL, Grevelding CG. Drug Discovery and Development for Schistosomiasis. ACTA ACUST UNITED AC 2019. [DOI: 10.1002/9783527808656.ch8] [Citation(s) in RCA: 11] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/19/2022]
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19
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Lombardo FC, Pasche V, Panic G, Endriss Y, Keiser J. Life cycle maintenance and drug-sensitivity assays for early drug discovery in Schistosoma mansoni. Nat Protoc 2019; 14:461-481. [PMID: 30610241 DOI: 10.1038/s41596-018-0101-y] [Citation(s) in RCA: 73] [Impact Index Per Article: 14.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/20/2022]
Abstract
Drug discovery for schistosomiasis is still limited to a handful of academic laboratories worldwide, with only a few novel antischistosomal lead compounds being actively researched. Despite recent international mobilization against the disease to stimulate and promote antischistosomal drug discovery, setting up a drug-screening flow with schistosome parasites remains challenging. Whereas numerous different protocols to obtain and cultivate schistosomes have been published, those describing the drug-screening process are scarce, and none gather together parasite cultivation and early drug discovery procedures. To help overcome this hurdle, we provide here a set of integrated methods either adapted from already-published protocols or based on our long-term experience in schistosomiasis research. Specifically, we detail the establishment and maintenance of the complex and several-week-long Schistosoma mansoni life cycle in a laboratory setting, as well as the means of retrieving and culturing the parasites at their relevant life stages. The in vitro and in vivo assays that are performed along the drug-screening cascade are also described. In these assays, which can be performed within 5 d, the effect of a drug is determined by phenotypic assessment of the parasites' viability and morphology, for which stage-specific scoring scales are proposed. Finally, the modalities for testing and evaluating a compound in vivo, constituting a procedure lasting up to 10 weeks, are presented in order to go from in vitro hit identification to the selection of early lead candidates.
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Affiliation(s)
- Flavio C Lombardo
- Department of Medical Parasitology and Infection Biology, Swiss Tropical and Public Health Institute, Basel, Switzerland.,University of Basel, Basel, Switzerland
| | - Valérian Pasche
- Department of Medical Parasitology and Infection Biology, Swiss Tropical and Public Health Institute, Basel, Switzerland.,University of Basel, Basel, Switzerland
| | - Gordana Panic
- Department of Medical Parasitology and Infection Biology, Swiss Tropical and Public Health Institute, Basel, Switzerland.,University of Basel, Basel, Switzerland
| | - Yvette Endriss
- Department of Medical Parasitology and Infection Biology, Swiss Tropical and Public Health Institute, Basel, Switzerland.,University of Basel, Basel, Switzerland
| | - Jennifer Keiser
- Department of Medical Parasitology and Infection Biology, Swiss Tropical and Public Health Institute, Basel, Switzerland. .,University of Basel, Basel, Switzerland.
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20
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Frahm S, Anisuzzaman A, Prodjinotho UF, Vejzagić N, Verschoor A, Prazeres da Costa C. A novel cell-free method to culture Schistosoma mansoni from cercariae to juvenile worm stages for in vitro drug testing. PLoS Negl Trop Dis 2019; 13:e0006590. [PMID: 30689639 PMCID: PMC6375649 DOI: 10.1371/journal.pntd.0006590] [Citation(s) in RCA: 21] [Impact Index Per Article: 4.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/04/2018] [Revised: 02/14/2019] [Accepted: 11/16/2018] [Indexed: 01/01/2023] Open
Abstract
Background The arsenal in anthelminthic treatment against schistosomiasis is limited and relies almost exclusively on a single drug, praziquantel (PZQ). Thus, resistance to PZQ could constitute a major threat. Even though PZQ is potent in killing adult worms, its activity against earlier stages is limited. Current in vitro drug screening strategies depend on newly transformed schistosomula (NTS) for initial hit identification, thereby limiting sensitivity to new compounds predominantly active in later developmental stages. Therefore, the aim of this study was to establish a highly standardized, straightforward and reliable culture method to generate and maintain advanced larval stages in vitro. We present here how this method can be a valuable tool to test drug efficacy at each intermediate larval stage, reducing the reliance on animal use (3Rs). Methodology/Principal findings Cercariae were mechanically transformed into skin-stage (SkS) schistosomula and successfully cultured for up to four weeks with no loss in viability in a commercially available medium. Under these serum- and cell-free conditions, development halted at the lung-stage (LuS). However, the addition of human serum (HSe) propelled further development into liver stage (LiS) worms within eight weeks. Skin and lung stages, as well as LiS, were submitted to 96-well drug screening assays using known anti-schistosomal compounds such as PZQ, oxamniquine (OXM), mefloquine (MFQ) and artemether (ART). Our findings showed stage-dependent differences in larval susceptibility to these compounds. Conclusion With this robust and highly standardized in vitro assay, important developmental stages of S. mansoni up to LiS worms can be generated and maintained over prolonged periods of time. The phenotype of LiS worms, when exposed to reference drugs, was comparable to most previously published works for ex vivo harvested adult worms. Therefore, this in vitro assay can help reduce reliance on animal experiments in search for new anti-schistosomal drugs. Schistosomiasis remains a major health threat, predominantly in developing countries. Even though there has been some progress in search of new drugs, praziquantel remains the only available drug. Probably the most important advance in the search for new drugs was in vitro transformation of cercariae and their subsequent culture. However, hit identification in compound screenings is exclusively tested in skin stage parasites and is only confirmed for more mature worms in a subsequent step. This is in part due to the lack of an easy culture system for advance-stage parasites. We present here a reliable and highly standardized way to generate LiS worms in vitro in a cell-free culture system. The inclusion of in vitro drug tests on advanced-stage parasites in initial hit identification will help to identify compounds that might otherwise be overlooked. Furthermore, the ability to continuously observe the parasite’s development in vitro will provide an important platform for a better understanding of its maturation in the human host. Taken together, this opens up new avenues to investigate the influence of specific cell types or host proteins on the development of Schistosoma mansoni and provides an additional tool to reduce animal use in future drug discovery efforts (3Rs).
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Affiliation(s)
- Sören Frahm
- Institute for Medical Microbiology, Immunology and Hygiene, Technische Universität München, Munich, Germany
| | - Anisuzzaman Anisuzzaman
- Institute for Medical Microbiology, Immunology and Hygiene, Technische Universität München, Munich, Germany
- Department of Parasitology, Bangladesh Agricultural University, Mymensingh, Bangladesh
| | - Ulrich Fabien Prodjinotho
- Institute for Medical Microbiology, Immunology and Hygiene, Technische Universität München, Munich, Germany
| | - Nermina Vejzagić
- Institute for Medical Microbiology, Immunology and Hygiene, Technische Universität München, Munich, Germany
| | - Admar Verschoor
- Institute for Systemic Inflammation Research, Universität zu Lübeck, Lübeck, Germany
| | - Clarissa Prazeres da Costa
- Institute for Medical Microbiology, Immunology and Hygiene, Technische Universität München, Munich, Germany
- * E-mail:
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21
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Chawla K, Modena MM, Ravaynia PS, Lombardo FC, Leonhardt M, Panic G, Bürgel SC, Keiser J, Hierlemann A. Impedance-Based Microfluidic Assay for Automated Antischistosomal Drug Screening. ACS Sens 2018; 3:2613-2620. [PMID: 30426744 PMCID: PMC6396876 DOI: 10.1021/acssensors.8b01027] [Citation(s) in RCA: 18] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/31/2022]
Abstract
Schistosomiasis is a neglected tropical disease, caused by parasitic worms, which affects almost 200 million people worldwide. For over 40 years, chemotherapeutic treatment has relied on the administration of praziquantel, an efficacious drug against schistosomiasis. However, concerns about developing drug resistance require the discovery of novel drug compounds. Currently, the drug-screening process is mostly based on the visual evaluation of drug effects on worm larvae in vitro by a trained operator. This manual process is extremely labor-intensive, has limited throughput, and may be affected by subjectivity of the operator evaluation. In this paper, we introduce a microfluidic platform with integrated electrodes for the automated detection of worm larvae viability using an impedance-based approach. The microfluidic analysis unit consists of two sets of electrodes and a channel of variable geometry to enable counting and size detection of single parasite larvae and the collective evaluation of the motility of the larvae as an unbiased estimator for their viability. The current platform also allows for multiplexing of the analysis units resulting in increased throughput. We used our platform to record size and motility variations of Schistosoma mansoni larvae exposed to different concentrations of mefloquine, a drug with established in vitro antischistosomal properties. The developed platform demonstrates the potential of integrated microfluidic platforms for high-throughput antischistosomal drug screening.
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Affiliation(s)
- Ketki Chawla
- ETH Zurich, Dept. of Biosystems Science and Engineering, Bio Engineering Laboratory, Basel, Switzerland
| | - Mario M. Modena
- ETH Zurich, Dept. of Biosystems Science and Engineering, Bio Engineering Laboratory, Basel, Switzerland
| | - Paolo S. Ravaynia
- ETH Zurich, Dept. of Biosystems Science and Engineering, Bio Engineering Laboratory, Basel, Switzerland
| | - Flavio C. Lombardo
- Swiss Tropical and Public Health Institute, Department of Medical Parasitology and Infection Biology, Basel, Switzerland
- University of Basel, Basel, Switzerland
| | - Martin Leonhardt
- ETH Zurich, Dept. of Biosystems Science and Engineering, Bio Engineering Laboratory, Basel, Switzerland
| | - Gordana Panic
- Swiss Tropical and Public Health Institute, Department of Medical Parasitology and Infection Biology, Basel, Switzerland
- University of Basel, Basel, Switzerland
| | - Sebastian C. Bürgel
- ETH Zurich, Dept. of Biosystems Science and Engineering, Bio Engineering Laboratory, Basel, Switzerland
| | - Jennifer Keiser
- Swiss Tropical and Public Health Institute, Department of Medical Parasitology and Infection Biology, Basel, Switzerland
- University of Basel, Basel, Switzerland
| | - Andreas Hierlemann
- ETH Zurich, Dept. of Biosystems Science and Engineering, Bio Engineering Laboratory, Basel, Switzerland
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22
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Hernandez HW, Soeung M, Zorn KM, Ashoura N, Mottin M, Andrade CH, Caffrey CR, de Siqueira-Neto JL, Ekins S. High Throughput and Computational Repurposing for Neglected Diseases. Pharm Res 2018; 36:27. [PMID: 30560386 PMCID: PMC6792295 DOI: 10.1007/s11095-018-2558-3] [Citation(s) in RCA: 28] [Impact Index Per Article: 4.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/26/2018] [Accepted: 12/09/2018] [Indexed: 12/21/2022]
Abstract
Purpose Neglected tropical diseases (NTDs) represent are a heterogeneous group of communicable diseases that are found within the poorest populations of the world. There are 23 NTDs that have been prioritized by the World Health Organization, which are endemic in 149 countries and affect more than 1.4 billion people, costing these developing economies billions of dollars annually. The NTDs result from four different causative pathogens: protozoa, bacteria, helminth and virus. The majority of the diseases lack effective treatments. Therefore, new therapeutics for NTDs are desperately needed. Methods We describe various high throughput screening and computational approaches that have been performed in recent years. We have collated the molecules identified in these studies and calculated molecular properties. Results Numerous global repurposing efforts have yielded some promising compounds for various neglected tropical diseases. These compounds when analyzed as one would expect appear drug-like. Several large datasets are also now in the public domain and this enables machine learning models to be constructed that then facilitate the discovery of new molecules for these pathogens. Conclusions In the space of a few years many groups have either performed experimental or computational repurposing high throughput screens against neglected diseases. These have identified compounds which in many cases are already approved drugs. Such approaches perhaps offer a more efficient way to develop treatments which are generally not a focus for global pharmaceutical companies because of the economics or the lack of a viable market. Other diseases could perhaps benefit from these repurposing approaches. Electronic supplementary material The online version of this article (10.1007/s11095-018-2558-3) contains supplementary material, which is available to authorized users.
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Affiliation(s)
| | - Melinda Soeung
- MD Anderson Cancer Center, University of Texas, Houston, Texas, USA
| | - Kimberley M Zorn
- Collaborations Pharmaceuticals Inc., 840 Main Campus Drive, Lab 3510, Raleigh, North Carolina, 27606, USA
| | | | - Melina Mottin
- LabMol - Laboratory for Molecular Modeling and Drug Design Faculdade de Farmacia, Universidade Federal de Goias - UFG, Goiânia, GO, 74605-170, Brazil
| | - Carolina Horta Andrade
- LabMol - Laboratory for Molecular Modeling and Drug Design Faculdade de Farmacia, Universidade Federal de Goias - UFG, Goiânia, GO, 74605-170, Brazil
| | - Conor R Caffrey
- Center for Discovery and Innovation in Parasitic Diseases, Skaggs School of Pharmacy and Pharmaceutical Sciences, University of California San Diego, San Diego, California, 92093, USA
| | - Jair Lage de Siqueira-Neto
- Center for Discovery and Innovation in Parasitic Diseases, Skaggs School of Pharmacy and Pharmaceutical Sciences, University of California San Diego, San Diego, California, 92093, USA
| | - Sean Ekins
- Collaborations Pharmaceuticals Inc., 840 Main Campus Drive, Lab 3510, Raleigh, North Carolina, 27606, USA.
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23
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Pereira ASA, Amaral MS, Vasconcelos EJR, Pires DS, Asif H, daSilva LF, Morales-Vicente DA, Carneiro VC, Angeli CB, Palmisano G, Fantappie MR, Pierce RJ, Setubal JC, Verjovski-Almeida S. Inhibition of histone methyltransferase EZH2 in Schistosoma mansoni in vitro by GSK343 reduces egg laying and decreases the expression of genes implicated in DNA replication and noncoding RNA metabolism. PLoS Negl Trop Dis 2018; 12:e0006873. [PMID: 30365505 PMCID: PMC6221359 DOI: 10.1371/journal.pntd.0006873] [Citation(s) in RCA: 23] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/10/2018] [Revised: 11/07/2018] [Accepted: 09/24/2018] [Indexed: 11/19/2022] Open
Abstract
Background The possibility of emergence of praziquantel-resistant Schistosoma parasites and the lack of other effective drugs demand the discovery of new schistosomicidal agents. In this context the study of compounds that target histone-modifying enzymes is extremely promising. Our aim was to investigate the effect of inhibition of EZH2, a histone methyltransferase that is involved in chromatin remodeling processes and gene expression control; we tested different developmental forms of Schistosoma mansoni using GKS343, a selective inhibitor of EZH2 in human cells. Methodology/Principal findings Adult male and female worms and schistosomula were treated with different concentrations of GSK343 for up to two days in vitro. Western blotting showed a decrease in the H3K27me3 histone mark in all three developmental forms. Motility, mortality, pairing and egg laying were employed as schistosomicidal parameters for adult worms. Schistosomula viability was evaluated with propidium iodide staining and ATP quantification. Adult worms showed decreased motility when exposed to GSK343. Also, an approximate 40% reduction of egg laying by GSK343-treated females was observed when compared with controls (0.1% DMSO). Scanning electron microscopy showed the formation of bulges and bubbles throughout the dorsal region of GSK343-treated adult worms. In schistosomula the body was extremely contracted with the presence of numerous folds, and growth was markedly slowed. RNA-seq was applied to identify the metabolic pathways affected by GSK343 sublethal doses. GSK343-treated adult worms showed significantly altered expression of genes related to transmembrane transport, cellular homeostasis and egg development. In females, genes related to DNA replication and noncoding RNA metabolism processes were downregulated. Schistosomula showed altered expression of genes related to cell adhesion and membrane synthesis pathways. Conclusions/Significance The results indicated that GSK343 presents in vitro activities against S. mansoni, and the characterization of EZH2 as a new potential molecular target establishes EZH2 inhibitors as part of a promising new group of compounds that could be used for the development of schistosomicidal agents. Schistosomiasis is a chronic and debilitating disease caused by a trematode of the genus Schistosoma. The current strategy for the control of the disease involves treatment with praziquantel, the only available drug. The development of new drugs is therefore a top priority. Drugs that inhibit histone modifying enzymes have been used in cancer, altering gene expression, replication, repair and DNA recombination. Schistosoma parasites have some characteristics similar to malignant tumors, such as intense cell division and high levels of metabolic activity. Here we evaluate in Schistosoma mansoni the effect of GSK343, an inhibitor of the histone methyltransferase EZH2 that had been shown to arrest or reduce the growth of human cancer cells. We show that GSK343 causes damage to the parasite tegument and reduces egg laying in vitro, concomitant with a decrease in levels of H3K27me3, the histone mark put in place by EZH2. RNA-seq and proteomic analyses of treated parasites showed changes in the expression of hundreds of genes involved in important metabolic processes. In females, a marked decrease was observed in the expression of genes related to processes such as DNA replication and noncoding RNA metabolism. In conclusion, the histone methyltransferase EZH2 seems to be a promising novel drug target against schistosomiasis.
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Affiliation(s)
- Adriana S. A. Pereira
- Laboratório de Parasitologia, Instituto Butantan, São Paulo, SP, Brasil
- Departamento de Bioquímica, Instituto de Química, Universidade de São Paulo, São Paulo, SP, Brasil
| | - Murilo S. Amaral
- Laboratório de Parasitologia, Instituto Butantan, São Paulo, SP, Brasil
| | - Elton J. R. Vasconcelos
- Laboratório de Parasitologia, Instituto Butantan, São Paulo, SP, Brasil
- Departamento de Bioquímica, Instituto de Química, Universidade de São Paulo, São Paulo, SP, Brasil
| | - David S. Pires
- Laboratório de Parasitologia, Instituto Butantan, São Paulo, SP, Brasil
| | - Huma Asif
- Laboratório de Parasitologia, Instituto Butantan, São Paulo, SP, Brasil
| | - Lucas F. daSilva
- Laboratório de Parasitologia, Instituto Butantan, São Paulo, SP, Brasil
- Departamento de Bioquímica, Instituto de Química, Universidade de São Paulo, São Paulo, SP, Brasil
| | - David A. Morales-Vicente
- Laboratório de Parasitologia, Instituto Butantan, São Paulo, SP, Brasil
- Departamento de Bioquímica, Instituto de Química, Universidade de São Paulo, São Paulo, SP, Brasil
| | - Vitor C. Carneiro
- Instituto de Bioquímica Médica Leopoldo de Meis, Universidade Federal do Rio de Janeiro, Rio de Janeiro, RJ, Brasil
| | - Claudia B. Angeli
- Instituto de Ciências Biomédicas, Departamento de Parasitologia, Laboratório de Glicoproteômica, Universidade de São Paulo, São Paulo, SP, Brasil
| | - Giuseppe Palmisano
- Instituto de Ciências Biomédicas, Departamento de Parasitologia, Laboratório de Glicoproteômica, Universidade de São Paulo, São Paulo, SP, Brasil
| | - Marcelo R. Fantappie
- Instituto de Bioquímica Médica Leopoldo de Meis, Universidade Federal do Rio de Janeiro, Rio de Janeiro, RJ, Brasil
| | - Raymond J. Pierce
- Centre d'Infection et d'Immunité de Lille, CNRS UMR 8204, Inserm U1019, CHU Lille, Institut Pasteur de Lille, Université de Lille, Lille, France
| | - João C. Setubal
- Departamento de Bioquímica, Instituto de Química, Universidade de São Paulo, São Paulo, SP, Brasil
| | - Sergio Verjovski-Almeida
- Laboratório de Parasitologia, Instituto Butantan, São Paulo, SP, Brasil
- Departamento de Bioquímica, Instituto de Química, Universidade de São Paulo, São Paulo, SP, Brasil
- * E-mail:
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24
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Bayer T, Chakrabarti A, Lancelot J, Shaik TB, Hausmann K, Melesina J, Schmidtkunz K, Marek M, Erdmann F, Schmidt M, Robaa D, Romier C, Pierce RJ, Jung M, Sippl W. Synthesis, Crystallization Studies, and in vitro Characterization of Cinnamic Acid Derivatives as SmHDAC8 Inhibitors for the Treatment of Schistosomiasis. ChemMedChem 2018; 13:1517-1529. [PMID: 29806110 DOI: 10.1002/cmdc.201800238] [Citation(s) in RCA: 17] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/11/2018] [Revised: 05/24/2018] [Indexed: 12/25/2022]
Abstract
Schistosomiasis is a neglected parasitic disease that affects more than 265 million people worldwide and for which the control strategy relies on mass treatment with only one drug: praziquantel. Based on the 3-chlorobenzothiophene-2-hydroxamic acid J1075, a series of hydroxamic acids with different scaffolds were prepared as potential inhibitors of Schistosoma mansoni histone deacetylase 8 (SmHDAC8). The crystal structures of SmHDAC8 with four inhibitors provided insight into the binding mode and orientation of molecules in the binding pocket as well as the orientation of its flexible amino acid residues. The compounds were evaluated in screens for inhibitory activity against schistosome and human HDACs. The most promising compounds were further investigated for their activity toward the major human HDAC isotypes. The most potent inhibitors were additionally screened for lethality against the schistosome larval stage using a fluorescence-based assay. Two of the compounds showed significant, dose-dependent killing of the schistosome larvae and markedly impaired egg laying of adult worm pairs maintained in culture.
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Affiliation(s)
- Theresa Bayer
- Institute of Pharmacy, Martin Luther University of Halle-Wittenberg, Wolfgang-Langenbeck-Str. 4, 06120, Halle/Saale, Germany
| | - Alokta Chakrabarti
- Institute of Pharmaceutical Sciences, University of Freiburg, 79104, Freiburg, Germany
| | - Julien Lancelot
- University of Lille, CNRS, Inserm, CHU Lille, Institut Pasteur de Lille, U1019-UMR 8204-CIIL-Centre d'Infection et d'Immunité de Lille, 59000, Lille, France
| | - Tajith B Shaik
- Département de Biologie Structurale Intégrative, Institut de Génétique et Biologie Moléculaire et Cellulaire (IGBMC), Université de Strasbourg, CNRS, INSERM, 67404, Illkirch Cedex, France
| | - Kristin Hausmann
- Institute of Pharmacy, Martin Luther University of Halle-Wittenberg, Wolfgang-Langenbeck-Str. 4, 06120, Halle/Saale, Germany
| | - Jelena Melesina
- Institute of Pharmacy, Martin Luther University of Halle-Wittenberg, Wolfgang-Langenbeck-Str. 4, 06120, Halle/Saale, Germany
| | - Karin Schmidtkunz
- Institute of Pharmaceutical Sciences, University of Freiburg, 79104, Freiburg, Germany
| | - Martin Marek
- Département de Biologie Structurale Intégrative, Institut de Génétique et Biologie Moléculaire et Cellulaire (IGBMC), Université de Strasbourg, CNRS, INSERM, 67404, Illkirch Cedex, France
| | - Frank Erdmann
- Institute of Pharmacy, Martin Luther University of Halle-Wittenberg, Wolfgang-Langenbeck-Str. 4, 06120, Halle/Saale, Germany
| | - Matthias Schmidt
- Institute of Pharmacy, Martin Luther University of Halle-Wittenberg, Wolfgang-Langenbeck-Str. 4, 06120, Halle/Saale, Germany
| | - Dina Robaa
- Institute of Pharmacy, Martin Luther University of Halle-Wittenberg, Wolfgang-Langenbeck-Str. 4, 06120, Halle/Saale, Germany
| | - Christophe Romier
- Département de Biologie Structurale Intégrative, Institut de Génétique et Biologie Moléculaire et Cellulaire (IGBMC), Université de Strasbourg, CNRS, INSERM, 67404, Illkirch Cedex, France
| | - Raymond J Pierce
- University of Lille, CNRS, Inserm, CHU Lille, Institut Pasteur de Lille, U1019-UMR 8204-CIIL-Centre d'Infection et d'Immunité de Lille, 59000, Lille, France
| | - Manfred Jung
- Institute of Pharmaceutical Sciences, University of Freiburg, 79104, Freiburg, Germany
| | - Wolfgang Sippl
- Institute of Pharmacy, Martin Luther University of Halle-Wittenberg, Wolfgang-Langenbeck-Str. 4, 06120, Halle/Saale, Germany
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Modena MM, Chawla K, Lombardo F, Bürgel SC, Panic G, Keiser J, Hierlemann A. Impedance-based detection of Schistosoma mansoni larvae viability for drug screening. IEEE BIOMEDICAL CIRCUITS AND SYSTEMS CONFERENCE : HEALTHCARE TECHNOLOGY : [PROCEEDINGS]. IEEE BIOMEDICAL CIRCUITS AND SYSTEMS CONFERENCE 2018; 2017. [PMID: 33409508 DOI: 10.1109/biocas.2017.8325227] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/16/2022]
Abstract
Human schistosomiasis is a neglected tropical disease caused by trematodes, affecting almost 250 million people worldwide. For the past 30 years, treatment has relied on the large-scale administration of praziquantel. However, concerns regarding the appearance of drug-resistance parasites require efforts in identifying novel classes of suitable drugs against schistosomiasis. The current drug screening system is manual, slow and subjective. We present here a microfluidic platform capable of detecting changes in viability of Schistosoma mansoni larvae (Newly Transformed Schistosomula, NTS). This platform could serve as a pre-screening tool for the identification of drug candidates. It is composed of a pair of coplanar electrodes integrated in a microfluidic channel for the detection and quantification of NTS motility. Comparison of viability detection by using our platform with the standard visual evaluation shows that our method is able to reliably detect viable and non-viable NTS at high sensitivity, also in case of low-motility parasites, while enabling a 10 fold decrease in sample consumption.
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Affiliation(s)
- Mario M Modena
- ETH Zurich, Dept. of Biosystems Science and Engineering, Bio Engineering Laboratory, Basel, Switzerland
| | - Ketki Chawla
- ETH Zurich, Dept. of Biosystems Science and Engineering, Bio Engineering Laboratory, Basel, Switzerland
| | - Flavio Lombardo
- Swiss Tropical and Public Health Institute, Department of Medical Parasitology and Infection Biology, Basel, Switzerland
| | - Sebastian C Bürgel
- ETH Zurich, Dept. of Biosystems Science and Engineering, Bio Engineering Laboratory, Basel, Switzerland
| | - Gordana Panic
- Swiss Tropical and Public Health Institute, Department of Medical Parasitology and Infection Biology, Basel, Switzerland
| | - Jennifer Keiser
- Swiss Tropical and Public Health Institute, Department of Medical Parasitology and Infection Biology, Basel, Switzerland
| | - Andreas Hierlemann
- ETH Zurich, Dept. of Biosystems Science and Engineering, Bio Engineering Laboratory, Basel, Switzerland
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Abstract
In the last 2 decades, renewed attention to neglected tropical diseases (NTDs) has spurred the development of antiparasitic agents, especially in light of emerging drug resistance. The need for new drugs has required in vitro screening methods using parasite culture. Furthermore, clinical laboratories sought to correlate in vitro susceptibility methods with treatment outcomes, most notably with malaria. Parasites with their various life cycles present greater complexity than bacteria, for which standardized susceptibility methods exist. This review catalogs the state-of-the-art methodologies used to evaluate the effects of drugs on key human parasites from the point of view of drug discovery as well as the need for laboratory methods that correlate with clinical outcomes.
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Bader C, Jesudoss Chelladurai J, Starling DE, Jones DE, Brewer MT. Assessment of in vitro killing assays for detecting praziquantel-induced death in Posthodiplostomum minimum metacercariae. Exp Parasitol 2017; 181:70-74. [PMID: 28760359 DOI: 10.1016/j.exppara.2017.07.008] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/08/2017] [Revised: 06/19/2017] [Accepted: 07/27/2017] [Indexed: 11/18/2022]
Abstract
Control of parasitic infections may be achieved by eliminating developmental stages present within intermediate hosts, thereby disrupting the parasite life cycle. For several trematodes relevant to human and veterinary medicine, this involves targeting the metacercarial stage found in fish intermediate hosts. Treatment of fish with praziquantel is one potential approach for targeting the metacercaria stage. To date, studies investigating praziquantel-induced metacercarial death in fish rely on counting parasites and visually assessing morphology or movement. In this study, we investigate quantitative methods for detecting praziquantel-induced death using a Posthodiplostomum minimum model. Our results revealed that propidium iodide staining accurately identified praziquantel-induced death and the level of staining was proportional to the concentration of praziquantel. In contrast, detection of ATP, resazurin metabolism, and trypan blue staining were poor indicators of metacercarial death. The propidium iodide method offers an advantage over simple visualization of parasite movement and could be used to determine EC50 values relevant for comparison of praziquantel sensitivity or resistance.
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Affiliation(s)
- Chris Bader
- Department of Veterinary Pathology, College of Veterinary Medicine, Iowa State University, Ames, Iowa, USA
| | - Jeba Jesudoss Chelladurai
- Department of Veterinary Pathology, College of Veterinary Medicine, Iowa State University, Ames, Iowa, USA
| | - David E Starling
- Department of Biomedical Sciences, College of Veterinary Medicine, Iowa State University, Ames, Iowa, USA
| | - Douglas E Jones
- Department of Veterinary Pathology, College of Veterinary Medicine, Iowa State University, Ames, Iowa, USA
| | - Matthew T Brewer
- Department of Veterinary Pathology, College of Veterinary Medicine, Iowa State University, Ames, Iowa, USA.
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Aguiar PHN, Fernandes NMGS, Zani CL, Mourão MM. A high-throughput colorimetric assay for detection of Schistosoma mansoni viability based on the tetrazolium salt XTT. Parasit Vectors 2017; 10:300. [PMID: 28637488 PMCID: PMC5480175 DOI: 10.1186/s13071-017-2240-3] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/23/2017] [Accepted: 06/11/2017] [Indexed: 11/17/2022] Open
Abstract
BACKGROUND Schistosoma mansoni is a trematode parasite that causes schistosomiasis, one of the most prevalent neglected tropical diseases, leading to the loss of 2.6 million disability-adjusted life years. Praziquantel is the only drug available, and new drugs are required. The most common strategy in schistosomiasis drug discovery is the use of the schistosomula larval-stage for a pre-screen in drug sensitivity assays. However, assessing schistosomula viability by microscopy has always been a limitation to the throughput of such assays. Hence, the development of validated, robust high-throughput in vitro assays for Schistosoma with simple readouts is needed. Here, we present a simple and affordable alternative to assess schistosomula viability. The method employed is based on the hydrosoluble tetrazolium salt XTT which has been widely used in other organisms but has never been used to drug screen in schistosomes. RESULTS We showed that schistosomula reduce XTT salt to a coloured formazan product and that absorbance levels reflected the viability and parasites number. This XTT viability assay was validated for high throughput screening of compounds in schistosomula, and dose-response curves of compounds could be reproduced. CONCLUSIONS We conclude that the XTT viability assay could be applied for the screening of large compounds collections in S. mansoni and accelerate the identification of novel antischistosomal compounds.
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Affiliation(s)
| | | | - Carlos Leomar Zani
- Laboratório de Química dos Produtos Naturais, René Rachou Research Center, FIOCRUZ, Belo Horizonte, Minas Gerais Brazil
| | - Marina Moraes Mourão
- Laboratório de Helmintologia e Malacologia Médica, René Rachou Research Center, FIOCRUZ, Belo Horizonte, Minas Gerais Brazil
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29
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Chua MJ, Arnold MSJ, Xu W, Lancelot J, Lamotte S, Späth GF, Prina E, Pierce RJ, Fairlie DP, Skinner-Adams TS, Andrews KT. Effect of clinically approved HDAC inhibitors on Plasmodium, Leishmania and Schistosoma parasite growth. INTERNATIONAL JOURNAL FOR PARASITOLOGY-DRUGS AND DRUG RESISTANCE 2016; 7:42-50. [PMID: 28107750 PMCID: PMC5241585 DOI: 10.1016/j.ijpddr.2016.12.005] [Citation(s) in RCA: 63] [Impact Index Per Article: 7.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 10/29/2016] [Revised: 12/21/2016] [Accepted: 12/22/2016] [Indexed: 12/11/2022]
Abstract
Malaria, schistosomiasis and leishmaniases are among the most prevalent tropical parasitic diseases and each requires new innovative treatments. Targeting essential parasite pathways, such as those that regulate gene expression and cell cycle progression, is a key strategy for discovering new drug leads. In this study, four clinically approved anti-cancer drugs (Vorinostat, Belinostat, Panobinostat and Romidepsin) that target histone/lysine deacetylase enzymes were examined for in vitro activity against Plasmodium knowlesi, Schistosoma mansoni, Leishmania amazonensis and L. donovani parasites and two for in vivo activity in a mouse malaria model. All four compounds were potent inhibitors of P. knowlesi malaria parasites (IC50 9-370 nM), with belinostat, panobinostat and vorinostat having 8-45 fold selectivity for the parasite over human neonatal foreskin fibroblast (NFF) or human embryonic kidney (HEK 293) cells, while romidepsin was not selective. Each of the HDAC inhibitor drugs caused hyperacetylation of P. knowlesi histone H4. None of the drugs was active against Leishmania amastigote or promastigote parasites (IC50 > 20 μM) or S. mansoni schistosomula (IC50 > 10 μM), however romidepsin inhibited S. mansoni adult worm parings and egg production (IC50 ∼10 μM). Modest in vivo activity was observed in P. berghei infected mice dosed orally with vorinostat or panobinostat (25 mg/kg twice daily for four days), with a significant reduction in parasitemia observed on days 4-7 and 4-10 after infection (P < 0.05), respectively.
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Affiliation(s)
- Ming Jang Chua
- Griffith Institute for Drug Discovery, Griffith University, Queensland, Australia
| | - Megan S J Arnold
- Griffith Institute for Drug Discovery, Griffith University, Queensland, Australia
| | - Weijun Xu
- Institute for Molecular Bioscience, The University of Queensland, Brisbane, 4072, Australia
| | - Julien Lancelot
- Univ. Lille, CNRS, Inserm, CHU Lille, Institut Pasteur de Lille, U1019 - UMR 8204- CIIL -Centre D'Infection et D'Immunité de Lille, F-59000 Lille, France
| | - Suzanne Lamotte
- Institut Pasteur and INSERM U1201, Unité de Parasitologie Moléculaire et Signalisation, Paris, France
| | - Gerald F Späth
- Institut Pasteur and INSERM U1201, Unité de Parasitologie Moléculaire et Signalisation, Paris, France
| | - Eric Prina
- Institut Pasteur and INSERM U1201, Unité de Parasitologie Moléculaire et Signalisation, Paris, France
| | - Raymond J Pierce
- Univ. Lille, CNRS, Inserm, CHU Lille, Institut Pasteur de Lille, U1019 - UMR 8204- CIIL -Centre D'Infection et D'Immunité de Lille, F-59000 Lille, France
| | - David P Fairlie
- Institute for Molecular Bioscience, The University of Queensland, Brisbane, 4072, Australia
| | - Tina S Skinner-Adams
- Griffith Institute for Drug Discovery, Griffith University, Queensland, Australia
| | - Katherine T Andrews
- Griffith Institute for Drug Discovery, Griffith University, Queensland, Australia.
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30
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Tekwu EM, Anyan WK, Boamah D, Baffour-Awuah KO, Keyetat Tekwu S, Penlap Beng V, Nyarko AK, Bosompem KM. Mechanically produced schistosomula as a higher-throughput tools for phenotypic pre-screening in drug sensitivity assays: current research and future trends. Biomark Res 2016; 4:21. [PMID: 27895916 PMCID: PMC5120492 DOI: 10.1186/s40364-016-0075-2] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/07/2016] [Accepted: 11/08/2016] [Indexed: 11/10/2022] Open
Abstract
It is crucial to develop new antischistosomal drugs since there is no vaccine and the whole world is relying on only a single drug for the treatment of schistosomiasis. One of the obstacles to the development of drugs is the absence of the high throughput objective screening methods to assess drug compounds efficacy. Thus for identification of new drug compounds candidates, fast and accurate in vitro assays are unavoidable and more research efforts in the field of drug discovery can target schistosomula. This review presents a substantial overview of the present state of in vitro drug sensitivity assays developed so far for the determination of anti-schistosomula activity of drug compounds, natural products and derivatives using newly transformed schistosomula (NTS). It highlights some of the challenges involved in in vitro compound screening using NTS and the way forward.
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Affiliation(s)
- Emmanuel Mouafo Tekwu
- Noguchi Memorial Institute for Medical Research (NMIMR), College of Health Sciences, University of Ghana, PO Box LG581 Legon, Accra, Ghana
- Laboratory for Tuberculosis Research and Pharmacology, Biotechnology Centre, Nkolbisson, University of Yaoundé 1, Yaoundé, Cameroon
| | - William Kofi Anyan
- Noguchi Memorial Institute for Medical Research (NMIMR), College of Health Sciences, University of Ghana, PO Box LG581 Legon, Accra, Ghana
| | - Daniel Boamah
- Centre for Plant Medicine Research (CPMR), Akwapim, Mampong, Ghana
| | - Kofi Owusu Baffour-Awuah
- Noguchi Memorial Institute for Medical Research (NMIMR), College of Health Sciences, University of Ghana, PO Box LG581 Legon, Accra, Ghana
| | | | - Veronique Penlap Beng
- Laboratory for Tuberculosis Research and Pharmacology, Biotechnology Centre, Nkolbisson, University of Yaoundé 1, Yaoundé, Cameroon
| | | | - Kwabena Mante Bosompem
- Noguchi Memorial Institute for Medical Research (NMIMR), College of Health Sciences, University of Ghana, PO Box LG581 Legon, Accra, Ghana
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31
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Neves BJ, Dantas RF, Senger MR, Melo-Filho CC, Valente WCG, de Almeida ACM, Rezende-Neto JM, Lima EFC, Paveley R, Furnham N, Muratov E, Kamentsky L, Carpenter AE, Braga RC, Silva-Junior FP, Andrade CH. Discovery of New Anti-Schistosomal Hits by Integration of QSAR-Based Virtual Screening and High Content Screening. J Med Chem 2016; 59:7075-88. [PMID: 27396732 PMCID: PMC5844225 DOI: 10.1021/acs.jmedchem.5b02038] [Citation(s) in RCA: 52] [Impact Index Per Article: 6.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/26/2022]
Abstract
Schistosomiasis is a debilitating neglected tropical disease, caused by flatworms of Schistosoma genus. The treatment relies on a single drug, praziquantel (PZQ), making the discovery of new compounds extremely urgent. In this work, we integrated QSAR-based virtual screening (VS) of Schistosoma mansoni thioredoxin glutathione reductase (SmTGR) inhibitors and high content screening (HCS) aiming to discover new antischistosomal agents. Initially, binary QSAR models for inhibition of SmTGR were developed and validated using the Organization for Economic Co-operation and Development (OECD) guidance. Using these models, we prioritized 29 compounds for further testing in two HCS platforms based on image analysis of assay plates. Among them, 2-[2-(3-methyl-4-nitro-5-isoxazolyl)vinyl]pyridine and 2-(benzylsulfonyl)-1,3-benzothiazole, two compounds representing new chemical scaffolds have activity against schistosomula and adult worms at low micromolar concentrations and therefore represent promising antischistosomal hits for further hit-to-lead optimization.
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Affiliation(s)
- Bruno J. Neves
- LabMol—Laboratory for Molecular Modeling and Drug Design, Faculdade de Farmácia, Universidade Federal de Goiás, Rua 240, Qd.87, Setor Leste Universitário, Goiânia 74605-510, Brazil
| | - Rafael F. Dantas
- LaBECFar—Laboratório de Bioquímica Experimental e Computacional de Fármacos, Instituto Oswaldo Cruz, Fundação Oswaldo Cruz, Av. Brasil, 4365, Rio de Janeiro 21040-900, Rio de Janeiro, Brazil
| | - Mario R. Senger
- LaBECFar—Laboratório de Bioquímica Experimental e Computacional de Fármacos, Instituto Oswaldo Cruz, Fundação Oswaldo Cruz, Av. Brasil, 4365, Rio de Janeiro 21040-900, Rio de Janeiro, Brazil
| | - Cleber C. Melo-Filho
- LabMol—Laboratory for Molecular Modeling and Drug Design, Faculdade de Farmácia, Universidade Federal de Goiás, Rua 240, Qd.87, Setor Leste Universitário, Goiânia 74605-510, Brazil
| | - Walter C. G. Valente
- LaBECFar—Laboratório de Bioquímica Experimental e Computacional de Fármacos, Instituto Oswaldo Cruz, Fundação Oswaldo Cruz, Av. Brasil, 4365, Rio de Janeiro 21040-900, Rio de Janeiro, Brazil
| | - Ana C. M. de Almeida
- LaBECFar—Laboratório de Bioquímica Experimental e Computacional de Fármacos, Instituto Oswaldo Cruz, Fundação Oswaldo Cruz, Av. Brasil, 4365, Rio de Janeiro 21040-900, Rio de Janeiro, Brazil
| | - João M. Rezende-Neto
- LaBECFar—Laboratório de Bioquímica Experimental e Computacional de Fármacos, Instituto Oswaldo Cruz, Fundação Oswaldo Cruz, Av. Brasil, 4365, Rio de Janeiro 21040-900, Rio de Janeiro, Brazil
| | - Elid F. C. Lima
- LaBECFar—Laboratório de Bioquímica Experimental e Computacional de Fármacos, Instituto Oswaldo Cruz, Fundação Oswaldo Cruz, Av. Brasil, 4365, Rio de Janeiro 21040-900, Rio de Janeiro, Brazil
| | - Ross Paveley
- Department of Infection and Immunity, London School of Hygiene and Tropical Medicine, London WC1E 7HT, United Kingdom
| | - Nicholas Furnham
- Department of Infection and Immunity, London School of Hygiene and Tropical Medicine, London WC1E 7HT, United Kingdom
| | - Eugene Muratov
- Laboratory for Molecular Modeling, Eshelman School of Pharmacy, University of North Carolina, Chapel Hill North Carolina 27955-7568, United States
| | - Lee Kamentsky
- Imaging Platform, Broad Institute of Massachusetts Institute of Technology and Harvard, Cambridge, Massachusetts 02142, United States
| | - Anne E. Carpenter
- Imaging Platform, Broad Institute of Massachusetts Institute of Technology and Harvard, Cambridge, Massachusetts 02142, United States
| | - Rodolpho C. Braga
- LabMol—Laboratory for Molecular Modeling and Drug Design, Faculdade de Farmácia, Universidade Federal de Goiás, Rua 240, Qd.87, Setor Leste Universitário, Goiânia 74605-510, Brazil
| | - Floriano P. Silva-Junior
- LaBECFar—Laboratório de Bioquímica Experimental e Computacional de Fármacos, Instituto Oswaldo Cruz, Fundação Oswaldo Cruz, Av. Brasil, 4365, Rio de Janeiro 21040-900, Rio de Janeiro, Brazil
| | - Carolina Horta Andrade
- LabMol—Laboratory for Molecular Modeling and Drug Design, Faculdade de Farmácia, Universidade Federal de Goiás, Rua 240, Qd.87, Setor Leste Universitário, Goiânia 74605-510, Brazil
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32
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Neves BJ, Muratov E, Machado RB, Andrade CH, Cravo PVL. Modern approaches to accelerate discovery of new antischistosomal drugs. Expert Opin Drug Discov 2016; 11:557-67. [PMID: 27073973 DOI: 10.1080/17460441.2016.1178230] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/13/2022]
Abstract
INTRODUCTION The almost exclusive use of only praziquantel for the treatment of schistosomiasis has raised concerns about the possible emergence of drug-resistant schistosomes. Consequently, there is an urgent need for new antischistosomal drugs. The identification of leads and the generation of high quality data are crucial steps in the early stages of schistosome drug discovery projects. AREAS COVERED Herein, the authors focus on the current developments in antischistosomal lead discovery, specifically referring to the use of automated in vitro target-based and whole-organism screens and virtual screening of chemical databases. They highlight the strengths and pitfalls of each of the above-mentioned approaches, and suggest possible roadmaps towards the integration of several strategies, which may contribute for optimizing research outputs and led to more successful and cost-effective drug discovery endeavors. EXPERT OPINION Increasing partnerships and access to funding for drug discovery have strengthened the battle against schistosomiasis in recent years. However, the authors believe this battle also includes innovative strategies to overcome scientific challenges. In this context, significant advances of in vitro screening as well as computer-aided drug discovery have contributed to increase the success rate and reduce the costs of drug discovery campaigns. Although some of these approaches were already used in current antischistosomal lead discovery pipelines, the integration of these strategies in a solid workflow should allow the production of new treatments for schistosomiasis in the near future.
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Affiliation(s)
- Bruno Junior Neves
- a LabMol - Laboratory for Molecular Modeling and Drug Design, Faculdade de Farmácia , Universidade Federal de Goiás , Goiânia , Brazil
| | - Eugene Muratov
- b Laboratory for Molecular Modeling, Eshelman School of Pharmacy , University of North Carolina , Chapel Hill , NC , USA
| | - Renato Beilner Machado
- c GenoBio - Laboratory of Genomics and Biotechnology, Instituto de Patologia Tropical e Saúde Pública , Universidade Federal de Goiás , Goiânia , Brazil
| | - Carolina Horta Andrade
- a LabMol - Laboratory for Molecular Modeling and Drug Design, Faculdade de Farmácia , Universidade Federal de Goiás , Goiânia , Brazil
| | - Pedro Vitor Lemos Cravo
- c GenoBio - Laboratory of Genomics and Biotechnology, Instituto de Patologia Tropical e Saúde Pública , Universidade Federal de Goiás , Goiânia , Brazil.,d Instituto de Higiene e Medicina Tropical , Universidade Nova de Lisboa , Lisbon , Portugal
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33
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Heimburg T, Chakrabarti A, Lancelot J, Marek M, Melesina J, Hauser AT, Shaik TB, Duclaud S, Robaa D, Erdmann F, Schmidt M, Romier C, Pierce RJ, Jung M, Sippl W. Structure-Based Design and Synthesis of Novel Inhibitors Targeting HDAC8 from Schistosoma mansoni for the Treatment of Schistosomiasis. J Med Chem 2016; 59:2423-35. [PMID: 26937828 DOI: 10.1021/acs.jmedchem.5b01478] [Citation(s) in RCA: 90] [Impact Index Per Article: 11.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/09/2023]
Abstract
Schistosomiasis is a major neglected parasitic disease that affects more than 265 million people worldwide and for which the control strategy consists of mass treatment with the only available drug, praziquantel. In this study, a series of new benzohydroxamates were prepared as potent inhibitors of Schistosoma mansoni histone deacetylase 8 (smHDAC8). Crystallographic analysis provided insights into the inhibition mode of smHDAC8 activity by these 3-amidobenzohydroxamates. The newly designed inhibitors were evaluated in screens for enzyme inhibitory activity against schistosome and human HDACs. Twenty-seven compounds were found to be active in the nanomolar range, and some of them showed selectivity toward smHDAC8 over the major human HDACs (1 and 6). The active benzohydroxamates were additionally screened for lethality against the schistosome larval stage using a fluorescence-based assay. Four of these showed significant dose-dependent killing of the schistosome larvae and markedly impaired egg laying of adult worm pairs maintained in culture.
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Affiliation(s)
- Tino Heimburg
- Institute of Pharmacy, Martin-Luther University of Halle-Wittenberg , 06120 Halle/Saale, Germany
| | - Alokta Chakrabarti
- Institute of Pharmaceutical Sciences, University of Freiburg , 79104 Freiburg, Germany
| | - Julien Lancelot
- Université de Lille, CNRS, Inserm , CHU Lille, Institut Pasteur de Lille, U1019 - UMR 8204 - CIIL - Centre d'Infection et d'Immunité de Lille, 59000 Lille, France
| | - Martin Marek
- Département de Biologie Structurale Intégrative, Institut de Génétique et Biologie Moléculaire et Cellulaire (IGBMC), Université de Strasbourg (UDS), CNRS, INSERM , 67404 Illkirch Cedex, France
| | - Jelena Melesina
- Institute of Pharmacy, Martin-Luther University of Halle-Wittenberg , 06120 Halle/Saale, Germany
| | | | - Tajith B Shaik
- Département de Biologie Structurale Intégrative, Institut de Génétique et Biologie Moléculaire et Cellulaire (IGBMC), Université de Strasbourg (UDS), CNRS, INSERM , 67404 Illkirch Cedex, France
| | - Sylvie Duclaud
- Département de Biologie Structurale Intégrative, Institut de Génétique et Biologie Moléculaire et Cellulaire (IGBMC), Université de Strasbourg (UDS), CNRS, INSERM , 67404 Illkirch Cedex, France
| | - Dina Robaa
- Institute of Pharmacy, Martin-Luther University of Halle-Wittenberg , 06120 Halle/Saale, Germany
| | - Frank Erdmann
- Institute of Pharmacy, Martin-Luther University of Halle-Wittenberg , 06120 Halle/Saale, Germany
| | - Matthias Schmidt
- Institute of Pharmacy, Martin-Luther University of Halle-Wittenberg , 06120 Halle/Saale, Germany
| | - Christophe Romier
- Département de Biologie Structurale Intégrative, Institut de Génétique et Biologie Moléculaire et Cellulaire (IGBMC), Université de Strasbourg (UDS), CNRS, INSERM , 67404 Illkirch Cedex, France
| | - Raymond J Pierce
- Université de Lille, CNRS, Inserm , CHU Lille, Institut Pasteur de Lille, U1019 - UMR 8204 - CIIL - Centre d'Infection et d'Immunité de Lille, 59000 Lille, France
| | - Manfred Jung
- Institute of Pharmaceutical Sciences, University of Freiburg , 79104 Freiburg, Germany
| | - Wolfgang Sippl
- Institute of Pharmacy, Martin-Luther University of Halle-Wittenberg , 06120 Halle/Saale, Germany
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Neves BJ, Dantas RF, Senger MR, Valente WCG, Rezende-Neto JDM, Chaves WT, Kamentsky L, Carpenter A, Silva-Junior FP, Andrade CH. The antidepressant drug paroxetine as a new lead candidate in schistosome drug discovery. MEDCHEMCOMM 2016. [DOI: 10.1039/c5md00596e] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
Abstract
Paroxetine is a new anti-schistosomal lead with potent activity against schistosomula and adult life stages of S. mansoni.
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