1
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Risi G, Liu M, Vairoletti F, Quinn RJ, Salinas G. A Screening of 10,240 NatureBank Fractions Identifies Nematicidal Activity in Agelasine-Containing Extracts from Sponges. JOURNAL OF NATURAL PRODUCTS 2024; 87:1532-1539. [PMID: 38853528 DOI: 10.1021/acs.jnatprod.3c01212] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/11/2024]
Abstract
Nematode infections affect a fifth of the human population, livestock, and crops worldwide, imposing a burden to global public health and economies, particularly in developing nations. Resistance to commercial anthelmintics has increased over the years in livestock infections and driven the pursuit for new drugs. We herein present a rapid, cost-effective, and automated assay for nematicide discovery using the free-living nematode Caenorhabditis elegans to screen a highly diverse natural product library enriched in bioactive molecules. Screening of 10,240 fractions obtained from extracts of various biological sources allowed the identification of 7 promising hit fractions, all from marine sponges. These fractions were further assayed for nematicidal activity against the sheep nematode parasite Haemonchus contortus and for innocuity in zebrafish. The most active extracts against parasites and innocuous toward vertebrates belong to two chemotypes. High-performance liquid chromatography (HPLC) coupled with nuclear magnetic resonance (NMR) revealed that the most abundant compound in one chemotype is halaminol A, an aminoalcohol previously identified in a small screen against H. contortus. Terpene-nucleotide hybrids known as agelasines predominate in the other chemotype. This study reinforces the power of C. elegans for nematicide discovery from large collections and the potential of the chemical diversity derived from marine invertebrate biota.
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Affiliation(s)
- Gastón Risi
- Worm Biology Lab, Institut Pasteur de Montevideo, 11400 Montevideo, Uruguay
| | - Miaomiao Liu
- Griffith Institute for Drug Discovery, Griffith University, Brisbane, Queensland 4101, Australia
| | - Franco Vairoletti
- Worm Biology Lab, Institut Pasteur de Montevideo, 11400 Montevideo, Uruguay
- Laboratorio de Química Farmacéutica, Departamento de Química Orgánica, Facultad de Química, Universidad de la República, 11200 Montevideo, Uruguay
| | - Ronald J Quinn
- Griffith Institute for Drug Discovery, Griffith University, Brisbane, Queensland 4101, Australia
| | - Gustavo Salinas
- Worm Biology Lab, Institut Pasteur de Montevideo, 11400 Montevideo, Uruguay
- Departamento de Biociencias, Facultad de Química, Universidad de la República, 11200 Montevideo, Uruguay
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2
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Shanley HT, Taki AC, Nguyen N, Wang T, Byrne JJ, Ang CS, Leeming MG, Nie S, Williamson N, Zheng Y, Young ND, Korhonen PK, Hofmann A, Wells TNC, Jabbar A, Sleebs BE, Gasser RB. Structure activity relationship and target prediction for ABX464 analogues in Caenorhabditis elegans. Bioorg Med Chem 2024; 98:117540. [PMID: 38134663 DOI: 10.1016/j.bmc.2023.117540] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/01/2023] [Revised: 11/20/2023] [Accepted: 12/02/2023] [Indexed: 12/24/2023]
Abstract
Global challenges with treatment failures and/or widespread resistance in parasitic worms against commercially available anthelmintics lend impetus to the development of new anthelmintics with novel mechanism(s) of action. The free-living nematode Caenorhabditis elegans is an important model organism used for drug discovery, including the screening and structure-activity investigation of new compounds, and target deconvolution. Previously, we conducted a whole-organism phenotypic screen of the 'Pandemic Response Box' (from Medicines for Malaria Venture, MMV) and identified a hit compound, called ABX464, with activity against C. elegans and a related, parasitic nematode, Haemonchus contortus. Here, we tested a series of 44 synthesized analogues to explore the pharmacophore of activity on C. elegans and revealed five compounds whose potency was similar or greater than that of ABX464, but which were not toxic to human hepatoma (HepG2) cells. Subsequently, we employed thermal proteome profiling (TPP), protein structure prediction and an in silico-docking algorithm to predict ABX464-target candidates. Taken together, the findings from this study contribute significantly to the early-stage drug discovery of a new nematocide based on ABX464. Future work is aimed at validating the ABX464-protein interactions identified here, and at assessing ABX464 and associated analogues against a panel of parasitic nematodes, towards developing a new anthelmintic with a mechanism of action that is distinct from any of the compounds currently-available commercially.
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Affiliation(s)
- Harrison T Shanley
- Department of Veterinary Biosciences, Melbourne Veterinary School, Faculty of Science, The University of Melbourne, Parkville, Victoria 3010, Australia; Chemical Biology Division, Walter and Eliza Hall Institute of Medical Research, Parkville, Victoria 3052, Australia
| | - Aya C Taki
- Department of Veterinary Biosciences, Melbourne Veterinary School, Faculty of Science, The University of Melbourne, Parkville, Victoria 3010, Australia
| | - Nghi Nguyen
- Chemical Biology Division, Walter and Eliza Hall Institute of Medical Research, Parkville, Victoria 3052, Australia
| | - Tao Wang
- Department of Veterinary Biosciences, Melbourne Veterinary School, Faculty of Science, The University of Melbourne, Parkville, Victoria 3010, Australia
| | - Joseph J Byrne
- Department of Veterinary Biosciences, Melbourne Veterinary School, Faculty of Science, The University of Melbourne, Parkville, Victoria 3010, Australia
| | - Ching-Seng Ang
- Melbourne Mass Spectrometry and Proteomics Facility, The Bio21 Molecular Science and Biotechnology Institute, The University of Melbourne, Parkville, Victoria 3010, Australia
| | - Michael G Leeming
- Melbourne Mass Spectrometry and Proteomics Facility, The Bio21 Molecular Science and Biotechnology Institute, The University of Melbourne, Parkville, Victoria 3010, Australia
| | - Shuai Nie
- Melbourne Mass Spectrometry and Proteomics Facility, The Bio21 Molecular Science and Biotechnology Institute, The University of Melbourne, Parkville, Victoria 3010, Australia
| | - Nicholas Williamson
- Melbourne Mass Spectrometry and Proteomics Facility, The Bio21 Molecular Science and Biotechnology Institute, The University of Melbourne, Parkville, Victoria 3010, Australia
| | - Yuanting Zheng
- Department of Veterinary Biosciences, Melbourne Veterinary School, Faculty of Science, The University of Melbourne, Parkville, Victoria 3010, Australia
| | - Neil D Young
- Department of Veterinary Biosciences, Melbourne Veterinary School, Faculty of Science, The University of Melbourne, Parkville, Victoria 3010, Australia
| | - Pasi K Korhonen
- Department of Veterinary Biosciences, Melbourne Veterinary School, Faculty of Science, The University of Melbourne, Parkville, Victoria 3010, Australia
| | - Andreas Hofmann
- Department of Veterinary Biosciences, Melbourne Veterinary School, Faculty of Science, The University of Melbourne, Parkville, Victoria 3010, Australia; National Reference Centre for Authentic Food, Max Rubner-Institut, 95326 Kulmbach, Germany
| | - Tim N C Wells
- Medicines for Malaria Venture (MMV), 1215 Geneva, Switzerland
| | - Abdul Jabbar
- Department of Veterinary Biosciences, Melbourne Veterinary School, Faculty of Science, The University of Melbourne, Parkville, Victoria 3010, Australia
| | - Brad E Sleebs
- Department of Veterinary Biosciences, Melbourne Veterinary School, Faculty of Science, The University of Melbourne, Parkville, Victoria 3010, Australia; Chemical Biology Division, Walter and Eliza Hall Institute of Medical Research, Parkville, Victoria 3052, Australia.
| | - Robin B Gasser
- Department of Veterinary Biosciences, Melbourne Veterinary School, Faculty of Science, The University of Melbourne, Parkville, Victoria 3010, Australia.
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3
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Samee A, Usman F, Wani TA, Farooq M, Shah HS, Javed I, Ahmad H, Khan R, Zargar S, Kausar S. Sulconazole-Loaded Solid Lipid Nanoparticles for Enhanced Antifungal Activity: In Vitro and In Vivo Approach. Molecules 2023; 28:7508. [PMID: 38005230 PMCID: PMC10672792 DOI: 10.3390/molecules28227508] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/09/2023] [Revised: 10/28/2023] [Accepted: 11/06/2023] [Indexed: 11/26/2023] Open
Abstract
Solid lipid nanoparticles (SLNs) have the advantages of a cell-specific delivery and sustained release of hydrophobic drugs that can be exploited against infectious diseases. The topical delivery of hydrophobic drugs needs pharmaceutical strategies to enhance drug permeation, which is a challenge faced by conventional formulations containing a drug suspended in gel, creams or ointments. We report the fabrication and optimization of SLNs with sulconazole (SCZ) as a model hydrophobic drug and then a formulation of an SLN-based topical gel against fungal infections. The SLNs were optimized through excipients of glyceryl monostearate and Phospholipon® 90 H as lipids and tween 20 as a surfactant for its size, drug entrapment and sustained release and resistance against aggregation. The SCZ-SLNs were physically characterized for their particle size (89.81 ± 2.64), polydispersity index (0.311 ± 0.07), zeta potential (-26.98 ± 1.19) and encapsulation efficiency (86.52 ± 0.53). The SCZ-SLNs showed sustained release of 85.29% drug at the 12 h timepoint. The TEM results demonstrated spherical morphology, while DSC, XRD and FTIR showed the compatibility of the drug inside SLNs. SCZ-SLNs were incorporated into a gel using carbopol and were further optimized for their rheological behavior, pH, homogeneity and spreadability on the skin. The antifungal activity against Candida albicans and Trichophyton rubrum was increased in comparison to a SCZ carbopol-based gel. In vivo antifungal activity in rabbits presented faster healing of skin fungal infections. The histopathological examination of the treated skin from rabbits presented restoration of the dermal architecture. In summary, the approach of formulating SLNs into a topical gel presented an advantageous drug delivery system against mycosis.
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Affiliation(s)
- Ayesha Samee
- Department of Pharmaceutics, Faculty of Pharmacy, Bahauddin Zakariya University, Multan 66000, Pakistan; (A.S.); (S.K.)
| | - Faisal Usman
- Department of Pharmaceutics, Faculty of Pharmacy, Bahauddin Zakariya University, Multan 66000, Pakistan; (A.S.); (S.K.)
| | - Tanveer A. Wani
- Department of Pharmaceutical Chemistry, College of Pharmacy, King Saud University, P.O. Box 2457, Riyadh 11451, Saudi Arabia;
| | - Mudassir Farooq
- Department of Manufacturing Pharmacy, Faculty of Pharmacy, Mahidol University, Bangkok 10400, Thailand;
| | - Hamid Saeed Shah
- Institute of Pharmaceutical Sciences, University of Veterinary and Animal Sciences, Syed Abdul Qadir Jillani (Out Fall) Road, Lahore 54000, Pakistan
| | - Ibrahim Javed
- Center for Pharmaceutical Innovation, Clinical and Health Sciences, The University of South Australia, North Terrace, Adelaide 5000, Australia;
| | - Hassan Ahmad
- Faculty of Pharmaceutical Sciences, University of Central Punjab, 1-Khayaban.e. Jinnah Road, Johar Town, Lahore 54000, Pakistan;
| | - Riffat Khan
- College of Pharmacy, University of Sargodha, Sargodha 40100, Pakistan;
| | - Seema Zargar
- Department of Biochemistry, College of Sciences, King Saud University, P.O. Box 22452, Riyadh 11451, Saudi Arabia;
| | - Safina Kausar
- Department of Pharmaceutics, Faculty of Pharmacy, Bahauddin Zakariya University, Multan 66000, Pakistan; (A.S.); (S.K.)
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4
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Coghlan A, Partridge FA, Duque-Correa MA, Rinaldi G, Clare S, Seymour L, Brandt C, Mkandawire TT, McCarthy C, Holroyd N, Nick M, Brown AE, Tonitiwong S, Sattelle DB, Berriman M. A drug repurposing screen for whipworms informed by comparative genomics. PLoS Negl Trop Dis 2023; 17:e0011205. [PMID: 37669291 PMCID: PMC10503962 DOI: 10.1371/journal.pntd.0011205] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/01/2023] [Revised: 09/15/2023] [Accepted: 07/06/2023] [Indexed: 09/07/2023] Open
Abstract
Hundreds of millions of people worldwide are infected with the whipworm Trichuris trichiura. Novel treatments are urgently needed as current drugs, such as albendazole, have relatively low efficacy. We have investigated whether drugs approved for other human diseases could be repurposed as novel anti-whipworm drugs. In a previous comparative genomics analysis, we identified 409 drugs approved for human use that we predicted to target parasitic worm proteins. Here we tested these ex vivo by assessing motility of adult worms of Trichuris muris, the murine whipworm, an established model for human whipworm research. We identified 14 compounds with EC50 values of ≤50 μM against T. muris ex vivo, and selected nine for testing in vivo. However, the best worm burden reduction seen in mice was just 19%. The high number of ex vivo hits against T. muris shows that we were successful at predicting parasite proteins that could be targeted by approved drugs. In contrast, the low efficacy of these compounds in mice suggest challenges due to their chemical properties (e.g. lipophilicity, polarity, molecular weight) and pharmacokinetics (e.g. absorption, distribution, metabolism, and excretion) that may (i) promote absorption by the host gastrointestinal tract, thereby reducing availability to the worms embedded in the large intestine, and/or (ii) restrict drug uptake by the worms. This indicates that identifying structural analogues that have reduced absorption by the host, and increased uptake by worms, may be necessary for successful drug development against whipworms.
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Affiliation(s)
- Avril Coghlan
- Wellcome Sanger Institute, Cambridge, United Kingdom
| | - Frederick A. Partridge
- University College London, London, United Kingdom
- School of Life Sciences, University of Westminster, London, United Kingdom
| | | | | | - Simon Clare
- Wellcome Sanger Institute, Cambridge, United Kingdom
| | - Lisa Seymour
- Wellcome Sanger Institute, Cambridge, United Kingdom
| | | | | | | | - Nancy Holroyd
- Wellcome Sanger Institute, Cambridge, United Kingdom
| | - Marina Nick
- University College London, London, United Kingdom
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5
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Hubbard IC, Thompson JS, Else KJ, Shears RK. Another decade of Trichuris muris research: An update and application of key discoveries. ADVANCES IN PARASITOLOGY 2023; 121:1-63. [PMID: 37474238 DOI: 10.1016/bs.apar.2023.05.002] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 07/22/2023]
Abstract
The mouse whipworm, Trichuris muris, has been used for over 60 years as a tractable model for human trichuriasis, caused by the related whipworm species, T. trichiura. The history of T. muris research, from the discovery of the parasite in 1761 to understanding the lifecycle and outcome of infection with different doses (high versus low dose infection), as well as the immune mechanisms associated with parasite expulsion and chronic infection have been detailed in an earlier review published in 2013. Here, we review recent advances in our understanding of whipworm biology, host-parasite interactions and basic immunology brought about using the T. muris mouse model, focussing on developments from the last decade. In addition to the traditional high/low dose infection models that have formed the mainstay of T. muris research to date, novel models involving trickle (repeated low dose) infection in laboratory mice or infection in wild or semi-wild mice have led to important insights into how immunity develops in situ in a multivariate environment, while the use of novel techniques such as the development of caecal organoids (enabling the study of larval development ex vivo) promise to deliver important insights into host-parasite interactions. In addition, the genome and transcriptome analyses of T. muris and T. trichiura have proven to be invaluable tools, particularly in the context of vaccine development and identification of secreted products including proteins, extracellular vesicles and micro-RNAs, shedding further light on how these parasites communicate with their host and modulate the immune response to promote their own survival.
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Affiliation(s)
- Isabella C Hubbard
- Centre for Bioscience, Manchester Metropolitan University, Manchester, United Kingdom; Department of Life Sciences, Faculty of Science and Engineering, Manchester Metropolitan University, Manchester, United Kingdom
| | - Jacob S Thompson
- Lydia Becker Institute for Immunology and Inflammation, Faculty of Biology Medicine and Health, University of Manchester, Manchester, United Kingdom
| | - Kathryn J Else
- Lydia Becker Institute for Immunology and Inflammation, Faculty of Biology Medicine and Health, University of Manchester, Manchester, United Kingdom
| | - Rebecca K Shears
- Centre for Bioscience, Manchester Metropolitan University, Manchester, United Kingdom; Department of Life Sciences, Faculty of Science and Engineering, Manchester Metropolitan University, Manchester, United Kingdom.
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6
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Aderibigbe SA, Idowu SO, Olaniyi AA. Isotonic, aqueous-based media as simple and suitable test media for short-term Haemonchus placei adult worm motility assay. Exp Parasitol 2023; 249:108516. [PMID: 36967034 DOI: 10.1016/j.exppara.2023.108516] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/16/2022] [Revised: 03/21/2023] [Accepted: 03/21/2023] [Indexed: 04/08/2023]
Abstract
The solvating power of test media used in anthelmintic assays is critical to the validity of assay results, especially when evaluating plant extracts. High solutes in media lowers its solvating power, altering the range of concentrations available for investigation and assay performance. To identify simplified, well-tolerated media for adult Haemonchus placei with improved solvating power, we investigated the impact of varying solutions of pH (2.5-8.5), salinity (19-154 mM), and normal saline (NS) incorporating dissolution enhancers (acetone, propylene glycol, DMSO and Tween-80; 10-40% v/v) on the nematode over 3 h at room temperature. The performance of identified media, NS and 20% Tween-80 in NS, were evaluated by preparing sample extracts (acetone extract Sarcocephalus latifolius, AESL20&10; and chloroform extract Vernonia amygdalina, CEVA20&10) stock solutions (20 and 10 mg/mL) in them, assessed their apparent dissolution, and each highest stock solution that dissolves the extracts evaluated for anthelmintic activity against H. placei. We found isotonicity to be the critical-to-worm survival factor as H. placei survived 100% in pH solutions 3.5-8.5, and saline solutions 39-154 mM. The dissolution enhancers, at 40%, gave no survival. At 30% and 20%, only Tween-80 gave 92.5% and 100% survival, respectively. At 10%, Tween-80, acetone, DMSO and propylene glycol gave 100%, 100%, 87.5% and 0% survival, respectively. In 20% Tween-80 in NS, AESL20&10 and CEVA20&10 dissolved, furnishing wider concentration range (20-0 mg/mL); whereas only AESL10 dissolved in NS (narrower concentration range, 10-0 mg/mL). The LC50s (mg/mL) of 7.67 (AESL10, NS) and 7.48 (AESL20, Tween-80 in NS) were not significantly different (p > 0.05), while CEVA20 (Tween-80 in NS) gave 2.67. Our findings show that NS and 20% Tween-80 in NS, as isotonic, aqueous-based media, are suitable, and well-tolerated as test media for adult H. placei in a short-term motility assay. Up to 30% Tween-80 could be used to enhance dissolution where necessary.
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Affiliation(s)
- Segun A Aderibigbe
- Department of Pharmaceutical Chemistry, University of Ibadan, Ibadan, Nigeria.
| | - Sunday O Idowu
- Department of Pharmaceutical Chemistry, University of Ibadan, Ibadan, Nigeria.
| | - Ajibola A Olaniyi
- Department of Pharmaceutical Chemistry, University of Ibadan, Ibadan, Nigeria
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7
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Multivariate chemogenomic screening prioritizes new macrofilaricidal leads. Commun Biol 2023; 6:44. [PMID: 36639423 PMCID: PMC9839782 DOI: 10.1038/s42003-023-04435-8] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/27/2022] [Accepted: 01/05/2023] [Indexed: 01/15/2023] Open
Abstract
Development of direct acting macrofilaricides for the treatment of human filariases is hampered by limitations in screening throughput imposed by the parasite life cycle. In vitro adult screens typically assess single phenotypes without prior enrichment for chemicals with antifilarial potential. We developed a multivariate screen that identified dozens of compounds with submicromolar macrofilaricidal activity, achieving a hit rate of >50% by leveraging abundantly accessible microfilariae. Adult assays were multiplexed to thoroughly characterize compound activity across relevant parasite fitness traits, including neuromuscular control, fecundity, metabolism, and viability. Seventeen compounds from a diverse chemogenomic library elicited strong effects on at least one adult trait, with differential potency against microfilariae and adults. Our screen identified five compounds with high potency against adults but low potency or slow-acting microfilaricidal effects, at least one of which acts through a novel mechanism. We show that the use of microfilariae in a primary screen outperforms model nematode developmental assays and virtual screening of protein structures inferred with deep learning. These data provide new leads for drug development, and the high-content and multiplex assays set a new foundation for antifilarial discovery.
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8
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Harrington S, Knox JJ, Burns AR, Choo KL, Au A, Kitner M, Haeberli C, Pyche J, D'Amata C, Kim YH, Volpatti JR, Guiliani M, Snider J, Wong V, Palmeira BM, Redman EM, Vaidya AS, Gilleard JS, Stagljar I, Cutler SR, Kulke D, Dowling JJ, Yip CM, Keiser J, Zasada I, Lautens M, Roy PJ. Egg-laying and locomotory screens with C. elegans yield a nematode-selective small molecule stimulator of neurotransmitter release. Commun Biol 2022; 5:865. [PMID: 36002479 PMCID: PMC9402605 DOI: 10.1038/s42003-022-03819-6] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/16/2022] [Accepted: 08/08/2022] [Indexed: 12/05/2022] Open
Abstract
Nematode parasites of humans, livestock and crops dramatically impact human health and welfare. Alarmingly, parasitic nematodes of animals have rapidly evolved resistance to anthelmintic drugs, and traditional nematicides that protect crops are facing increasing restrictions because of poor phylogenetic selectivity. Here, we exploit multiple motor outputs of the model nematode C. elegans towards nematicide discovery. This work yielded multiple compounds that selectively kill and/or immobilize diverse nematode parasites. We focus on one compound that induces violent convulsions and paralysis that we call nementin. We find that nementin stimulates neuronal dense core vesicle release, which in turn enhances cholinergic signaling. Consequently, nementin synergistically enhances the potency of widely-used non-selective acetylcholinesterase (AChE) inhibitors, but in a nematode-selective manner. Nementin therefore has the potential to reduce the environmental impact of toxic AChE inhibitors that are used to control nematode infections and infestations. A C. elegans-based screening approach identifies nementin as a nematode-selective nematicide that can be used synergistically with acetylcholinesterase inhibitors
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Affiliation(s)
- Sean Harrington
- Department of Pharmacology and Toxicology, University of Toronto, Toronto, Canada.,The Donnelly Centre for Cellular and Biomolecular Research, University of Toronto, Toronto, Canada
| | - Jessica J Knox
- The Donnelly Centre for Cellular and Biomolecular Research, University of Toronto, Toronto, Canada.,Department of Molecular Genetics, University of Toronto, Toronto, Canada
| | - Andrew R Burns
- The Donnelly Centre for Cellular and Biomolecular Research, University of Toronto, Toronto, Canada.,Department of Molecular Genetics, University of Toronto, Toronto, Canada
| | - Ken-Loon Choo
- The Department of Chemistry, University of Toronto, Toronto, Canada
| | - Aaron Au
- The Donnelly Centre for Cellular and Biomolecular Research, University of Toronto, Toronto, Canada.,Institute of Biomaterials and Biomedical Engineering, University of Toronto, Toronto, Canada
| | - Megan Kitner
- USDA-ARS Horticultural Crops Research Laboratory, Corvallis, OR, USA
| | - Cecile Haeberli
- Department of Medical Parasitology and Infection Biology, Swiss-Tropical and Public Health Institute, (Swiss TPH), Basel, Switzerland.,Faculty of Science, University of Basel, Basel, Switzerland
| | - Jacob Pyche
- Department of Pharmacology and Toxicology, University of Toronto, Toronto, Canada.,The Donnelly Centre for Cellular and Biomolecular Research, University of Toronto, Toronto, Canada
| | - Cassandra D'Amata
- The Donnelly Centre for Cellular and Biomolecular Research, University of Toronto, Toronto, Canada
| | - Yong-Hyun Kim
- The Department of Chemistry, University of Toronto, Toronto, Canada
| | - Jonathan R Volpatti
- Program in Developmental and Stem Cell Biology, The Hospital for Sick Children, Toronto, Canada.,Program in Genetics and Genome Biology, The Hospital for Sick Children, Toronto, Canada
| | - Maximillano Guiliani
- The Donnelly Centre for Cellular and Biomolecular Research, University of Toronto, Toronto, Canada.,Institute of Biomaterials and Biomedical Engineering, University of Toronto, Toronto, Canada
| | - Jamie Snider
- The Donnelly Centre for Cellular and Biomolecular Research, University of Toronto, Toronto, Canada
| | - Victoria Wong
- The Donnelly Centre for Cellular and Biomolecular Research, University of Toronto, Toronto, Canada
| | - Bruna M Palmeira
- Department of Comparative Biology and Experimental Medicine, Host-Parasite Interactions (HPI) Program, Faculty of Veterinary Medicine, University of Calgary, Calgary, Canada
| | - Elizabeth M Redman
- Department of Comparative Biology and Experimental Medicine, Host-Parasite Interactions (HPI) Program, Faculty of Veterinary Medicine, University of Calgary, Calgary, Canada
| | - Aditya S Vaidya
- Institute for Integrative Genome Biology, University of California, Riverside, CA, USA.,Department of Botany and Plant Sciences, University of California, Riverside, CA, USA
| | - John S Gilleard
- Department of Comparative Biology and Experimental Medicine, Host-Parasite Interactions (HPI) Program, Faculty of Veterinary Medicine, University of Calgary, Calgary, Canada
| | - Igor Stagljar
- The Donnelly Centre for Cellular and Biomolecular Research, University of Toronto, Toronto, Canada.,Department of Molecular Genetics, University of Toronto, Toronto, Canada.,Department of Biochemistry, University of Toronto, Toronto, Canada.,Mediterranean Institute for Life Sciences, Split, Croatia.,School of Medicine, University of Split, Split, Croatia
| | - Sean R Cutler
- Institute for Integrative Genome Biology, University of California, Riverside, CA, USA.,Department of Botany and Plant Sciences, University of California, Riverside, CA, USA
| | - Daniel Kulke
- Research Parasiticides, Bayer Animal Health GmbH, Monheim, Germany.,Department of Biomedical Sciences, Iowa State University, Ames, IA, USA.,Global Innovation, Boehringer Ingelheim Vetmedica GmbH, Ingelheim am Rhein, Germany
| | - James J Dowling
- Program in Developmental and Stem Cell Biology, The Hospital for Sick Children, Toronto, Canada.,Program in Genetics and Genome Biology, The Hospital for Sick Children, Toronto, Canada
| | - Christopher M Yip
- The Donnelly Centre for Cellular and Biomolecular Research, University of Toronto, Toronto, Canada.,Institute of Biomaterials and Biomedical Engineering, University of Toronto, Toronto, Canada
| | - Jennifer Keiser
- Department of Medical Parasitology and Infection Biology, Swiss-Tropical and Public Health Institute, (Swiss TPH), Basel, Switzerland.,Faculty of Science, University of Basel, Basel, Switzerland
| | - Inga Zasada
- USDA-ARS Horticultural Crops Research Laboratory, Corvallis, OR, USA
| | - Mark Lautens
- The Department of Chemistry, University of Toronto, Toronto, Canada
| | - Peter J Roy
- Department of Pharmacology and Toxicology, University of Toronto, Toronto, Canada. .,The Donnelly Centre for Cellular and Biomolecular Research, University of Toronto, Toronto, Canada. .,Department of Molecular Genetics, University of Toronto, Toronto, Canada.
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9
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Hawryluk N, Zhiru L, Carlow C, Gokool S, Townson S, Kreiss T, Chojnowski A, Prorok M, Siekierka J, Ehrens A, Koschel M, Lhermitte-Vallarino N, Martin C, Hoerauf A, Hernandez G, Canan S, Khetani V, Zeldis J, Specht S, Hübner MP, Scandale I. Filarial nematode phenotypic screening cascade to identify compounds with anti-parasitic activity for drug discovery optimization. Int J Parasitol Drugs Drug Resist 2022; 19:89-97. [PMID: 35834918 PMCID: PMC9278491 DOI: 10.1016/j.ijpddr.2022.06.002] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/18/2021] [Revised: 06/13/2022] [Accepted: 06/13/2022] [Indexed: 11/18/2022]
Abstract
Filarial diseases, including lymphatic filariasis and onchocerciasis, are considered among the most devastating of all tropical diseases, affecting over 86 million people worldwide. To control and more rapidly eliminate onchocerciasis requires treatments that target the adult stage of the parasite. Drug discovery efforts are challenged by the lack of preclinical animal models using the human-pathogenic filariae, requiring the use of surrogate parasites for Onchocerca volvulus for both ex vivo and in vivo evaluation. Herein, we describe a platform utilizing phenotypic ex vivo assays consisting of the free-living nematode Caenorhabditis elegans, microfilariae and adult filariae of the bovine filariae Onchocerca lienalis and Onchocerca gutturosa, respectively, as well as microfilariae and adult filariae of the feline filariae Brugia pahangi, the rodent filariae Litomosoides sigmodontis and the human-pathogenic filariae Brugia malayi to assess activity across various surrogate parasites. Utilization of those surrogate nematodes for phenotypic ex vivo assays in order to assess activity across various parasites led to the successful establishment of a screening cascade and identification of multiple compounds with potential macrofilaricidal activity and desirable physicochemical, MW = 200-400 and low lipophilicity, logP <4, and pharmacokinetic properties, rat and human liver S9 stability of ≥70% remaining at 60 min, and AUC exposures above 3 μM h. This platform demonstrated the successful establishment of a screening cascade which resulted in the discovery of potential novel macrofilaricidal compounds for futher drug discovery lead optimization efforts. This screening cascade identified two distinct chemical series wherein one compound produced a significant 68% reduction of adult Litomosoides sigmodontis in the mouse model. Successful demonstration of efficacy prompted lead optimization medicinal chemistry efforts for this novel series.
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Affiliation(s)
| | - Li Zhiru
- New England Biolabs, Ipswich, MA, USA
| | | | - Suzanne Gokool
- Northwick Park Institute for Medical Research, London, UK
| | - Simon Townson
- Northwick Park Institute for Medical Research, London, UK
| | - Tamara Kreiss
- Sokol Institute of Pharmaceutical Life Sciences, Montclair State University, Montclair, NJ, USA
| | - Agnieszka Chojnowski
- Sokol Institute of Pharmaceutical Life Sciences, Montclair State University, Montclair, NJ, USA
| | - Monika Prorok
- Sokol Institute of Pharmaceutical Life Sciences, Montclair State University, Montclair, NJ, USA
| | - John Siekierka
- Sokol Institute of Pharmaceutical Life Sciences, Montclair State University, Montclair, NJ, USA
| | - Alexandra Ehrens
- Institute for Medical Microbiology, Immunology and Parasitology, University Hospital Bonn, Germany; German Center for Infection Research (DZIF), Partner Site Bonn-Cologne, Bonn, Germany
| | - Marianne Koschel
- Institute for Medical Microbiology, Immunology and Parasitology, University Hospital Bonn, Germany
| | | | - Coralie Martin
- Unité Molécules de Communication et Adaptation des Microorganismes (MCAM, UMR 7245), Muséum national d'Histoire naturelle, Paris, France
| | - Achim Hoerauf
- Institute for Medical Microbiology, Immunology and Parasitology, University Hospital Bonn, Germany; German Center for Infection Research (DZIF), Partner Site Bonn-Cologne, Bonn, Germany
| | | | | | | | | | - Sabine Specht
- Institute for Medical Microbiology, Immunology and Parasitology, University Hospital Bonn, Germany; Drugs for Neglected Diseases Initiative, Geneva, Switzerland
| | - Marc P Hübner
- Institute for Medical Microbiology, Immunology and Parasitology, University Hospital Bonn, Germany; German Center for Infection Research (DZIF), Partner Site Bonn-Cologne, Bonn, Germany
| | - Ivan Scandale
- Drugs for Neglected Diseases Initiative, Geneva, Switzerland
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10
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Zárate-Potes A, Ali I, Ribeiro Camacho M, Brownless H, Benedetto A. Meta-Analysis of Caenorhabditis elegans Transcriptomics Implicates Hedgehog-Like Signaling in Host-Microbe Interactions. Front Microbiol 2022; 13:853629. [PMID: 35620104 PMCID: PMC9127769 DOI: 10.3389/fmicb.2022.853629] [Citation(s) in RCA: 4] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/12/2022] [Accepted: 03/07/2022] [Indexed: 11/13/2022] Open
Abstract
Controlling nematode-caused diseases that affect cattle and crops world-wide remains a critical economic issue, owing to the lack of effective sustainable interventions. The interdependence of roundworms and their environmental microbes, including their microbiota, offers an opportunity for developing more targeted anthelminthic strategies. However, paucity of information and a currently narrow understanding of nematode-microbe interactions limited to specific infection contexts has precluded us from exploiting it. With the advent of omics approaches to map host-microbe genetic interactions, particularly in the model roundworm Caenorhabditis elegans, large datasets are now available across multiple models, that enable identification of nematode-microbe-specific pathways. In this work we collected 20 transcriptomic datasets documenting gene expression changes of C. elegans exposed to 20 different commensal and pathogenic microbes, performing gene enrichment analyses followed by functional testing using RNA interference directed toward genes of interest, before contrasting results from transcriptomic meta-analyses and phenomics. Differential expression analyses revealed a broad enrichment in signaling, innate immune response and (lipid) metabolism genes. Amongst signaling gene families, the nematode-divergent and expanded Hedgehog-like signaling (HHLS) pathway featured prominently. Indeed, 24/60 C. elegans Hedgehog-like proteins (HRPs) and 15/27 Patched-related receptors (PTRs) were differentially expressed in at least four microbial contexts, while up to 32/60 HRPs could be differentially expressed in a single context. interestingly, differentially expressed genes followed a microbe-specific pattern, suggestive of an adaptive microbe-specific response. To investigate this further, we knocked-down 96 individual HHLS genes by RNAi, using high-throughput assays to assess their impact on three worm-gut infection models (Pseudomonas aeruginosa, Staphylococcus aureus, and Enterococcus faecalis) and two worm-commensal paradigms (Comamonas sp., and Bacillus subtilis). We notably identified new putative infection response genes whose upregulation was required for normal pathogen resistance (i.e., grl-21 and ptr-18 protective against E. faecalis), as well as commensal-specific host-gene expression changes that are required for normal host stress handling. Importantly, interactions appeared more microbe-specific than shared. Our results thus implicate the Hedgehog-like signaling pathway in the modulation and possibly fine-tuning of nematode-microbe interactions and support the idea that interventions targeting this pathway may provide a new avenue for anthelmintic development.
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11
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Žofka M, Thuy Nguyen L, Mašátová E, Matoušková P. Image recognition based on deep learning in Haemonchus contortus motility assays. Comput Struct Biotechnol J 2022; 20:2372-2380. [PMID: 35664223 PMCID: PMC9127531 DOI: 10.1016/j.csbj.2022.05.014] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/04/2022] [Revised: 04/22/2022] [Accepted: 05/08/2022] [Indexed: 11/04/2022] Open
Abstract
Poor efficacy of some anthelmintics and rising concerns about the widespread drug resistance have highlighted the need for new drug discovery. The parasitic nematode Haemonchus contortus is an important model organism widely used for studies of drug resistance and drug screening with the current gold standard being the motility assay. We applied a deep learning approach Mask R-CNN for analysing motility videos containing varying rates of motile worms and compared it to other commonly used algorithms with different levels of complexity, namely the Wiggle Index and the Wide Field-of-View Nematode Tracking Platform. Mask R-CNN consistently outperformed the other algorithms in terms of the detection of worms as well as the precision of motility forecasts, having a mean absolute percentage error of 7.6% and a mean absolute error of 5.6% for the detection and motility forecasts, respectively. Using Mask R-CNN for motility assays confirmed the common problem with algorithms that use non-maximum suppression in detecting overlapping objects, which negatively impacts the overall precision. The use of intersect over union as a measure of the classification of motile / non-motile instances had an overall accuracy of 89%, indicating that it is a viable alternative to previously used methods based on movement characteristics, such as body bends. In comparison to the existing methods evaluated here, Mask R-CNN performed better and we anticipate that this method will broaden the number of possible approaches to video analysis of worm motility.
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12
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Chen W, Wang J, Huang D, Cheng W, Shao Z, Cai M, Zheng L, Yu Z, Zhang J. Volatile Organic Compounds from Bacillus aryabhattai MCCC 1K02966 with Multiple Modes against Meloidogyne incognita. MOLECULES (BASEL, SWITZERLAND) 2021; 27:molecules27010103. [PMID: 35011333 PMCID: PMC8747049 DOI: 10.3390/molecules27010103] [Citation(s) in RCA: 10] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 12/07/2021] [Revised: 12/21/2021] [Accepted: 12/22/2021] [Indexed: 11/16/2022]
Abstract
Plant-parasitic nematodes cause severe losses to crop production and economies all over the world. Bacillus aryabhattai MCCC 1K02966, a deep-sea bacterium, was obtained from the Southwest Indian Ocean and showed nematicidal and fumigant activities against Meloidogyne incognita in vitro. The nematicidal volatile organic compounds (VOCs) from the fermentation broth of B. aryabhattai MCCC 1K02966 were investigated further using solid-phase microextraction gas chromatography-mass spectrometry. Four VOCs, namely, pentane, 1-butanol, methyl thioacetate, and dimethyl disulfide, were identified in the fermentation broth. Among these VOCs, methyl thioacetate exhibited multiple nematicidal activities, including contact nematicidal, fumigant, and repellent activities against M. incognita. Methyl thioacetate showed a significant contact nematicidal activity with 87.90% mortality at 0.01 mg/mL by 72 h, fumigant activity in mortality 91.10% at 1 mg/mL by 48 h, and repellent activity at 0.01-10 mg/mL. In addition, methyl thioacetate exhibited 80-100% egg-hatching inhibition on the 7th day over the range of 0.5 mg/mL to 5 mg/mL. These results showed that methyl thioacetate from MCCC 1K02966 control M. incognita with multiple nematicidal modes and can be used as a potential biological control agent.
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Affiliation(s)
- Wen Chen
- State Key Laboratory of Agricultural Microbiology, National Engineering Research Center of Microbe Pesticides, College of Life Science and Technology, Huazhong Agricultural University, Wuhan 430070, China; (W.C.); (J.W.); (D.H.); (W.C.); (M.C.); (L.Z.); (Z.Y.)
| | - Jinping Wang
- State Key Laboratory of Agricultural Microbiology, National Engineering Research Center of Microbe Pesticides, College of Life Science and Technology, Huazhong Agricultural University, Wuhan 430070, China; (W.C.); (J.W.); (D.H.); (W.C.); (M.C.); (L.Z.); (Z.Y.)
| | - Dian Huang
- State Key Laboratory of Agricultural Microbiology, National Engineering Research Center of Microbe Pesticides, College of Life Science and Technology, Huazhong Agricultural University, Wuhan 430070, China; (W.C.); (J.W.); (D.H.); (W.C.); (M.C.); (L.Z.); (Z.Y.)
| | - Wanli Cheng
- State Key Laboratory of Agricultural Microbiology, National Engineering Research Center of Microbe Pesticides, College of Life Science and Technology, Huazhong Agricultural University, Wuhan 430070, China; (W.C.); (J.W.); (D.H.); (W.C.); (M.C.); (L.Z.); (Z.Y.)
| | - Zongze Shao
- Key Laboratory of Marine Biogenetic Resources, Third Institute of Oceanography, Ministry of Natural Resources, Xiamen 361005, China;
| | - Minmin Cai
- State Key Laboratory of Agricultural Microbiology, National Engineering Research Center of Microbe Pesticides, College of Life Science and Technology, Huazhong Agricultural University, Wuhan 430070, China; (W.C.); (J.W.); (D.H.); (W.C.); (M.C.); (L.Z.); (Z.Y.)
| | - Longyu Zheng
- State Key Laboratory of Agricultural Microbiology, National Engineering Research Center of Microbe Pesticides, College of Life Science and Technology, Huazhong Agricultural University, Wuhan 430070, China; (W.C.); (J.W.); (D.H.); (W.C.); (M.C.); (L.Z.); (Z.Y.)
| | - Ziniu Yu
- State Key Laboratory of Agricultural Microbiology, National Engineering Research Center of Microbe Pesticides, College of Life Science and Technology, Huazhong Agricultural University, Wuhan 430070, China; (W.C.); (J.W.); (D.H.); (W.C.); (M.C.); (L.Z.); (Z.Y.)
| | - Jibin Zhang
- State Key Laboratory of Agricultural Microbiology, National Engineering Research Center of Microbe Pesticides, College of Life Science and Technology, Huazhong Agricultural University, Wuhan 430070, China; (W.C.); (J.W.); (D.H.); (W.C.); (M.C.); (L.Z.); (Z.Y.)
- Correspondence: ; Tel.: +86-27-8728-7701; Fax: +86-27-8728-7254
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13
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Adegboye O, Field MA, Kupz A, Pai S, Sharma D, Smout MJ, Wangchuk P, Wong Y, Loiseau C. Natural-Product-Based Solutions for Tropical Infectious Diseases. Clin Microbiol Rev 2021; 34:e0034820. [PMID: 34494873 PMCID: PMC8673330 DOI: 10.1128/cmr.00348-20] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/22/2022] Open
Abstract
About half of the world's population and 80% of the world's biodiversity can be found in the tropics. Many diseases are specific to the tropics, with at least 41 diseases caused by endemic bacteria, viruses, parasites, and fungi. Such diseases are of increasing concern, as the geographic range of tropical diseases is expanding due to climate change, urbanization, change in agricultural practices, deforestation, and loss of biodiversity. While traditional medicines have been used for centuries in the treatment of tropical diseases, the active natural compounds within these medicines remain largely unknown. In this review, we describe infectious diseases specific to the tropics, including their causative pathogens, modes of transmission, recent major outbreaks, and geographic locations. We further review current treatments for these tropical diseases, carefully consider the biodiscovery potential of the tropical biome, and discuss a range of technologies being used for drug development from natural resources. We provide a list of natural products with antimicrobial activity, detailing the source organisms and their effectiveness as treatment. We discuss how technological advancements, such as next-generation sequencing, are driving high-throughput natural product screening pipelines to identify compounds with therapeutic properties. This review demonstrates the impact natural products from the vast tropical biome have in the treatment of tropical infectious diseases and how high-throughput technical capacity will accelerate this discovery process.
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Affiliation(s)
- Oyelola Adegboye
- Public Health and Tropical Medicine, College of Public Health, Medical and Veterinary Sciences, James Cook University, Townsville, QLD, Australia
- World Health Organization Collaborating Center for Vector-Borne and Neglected Tropical Diseases, College of Public Health, Medical and Veterinary Sciences, James Cook University, Townsville, QLD, Australia
- Australian Institute of Tropical Health and Medicine, James Cook University, Cairns, QLD, Australia
| | - Matt A. Field
- Australian Institute of Tropical Health and Medicine, James Cook University, Cairns, QLD, Australia
- Centre for Tropical Bioinformatics and Molecular Biology, James Cook University, Cairns, QLD, Australia
- Centre for Molecular Therapeutics, James Cook University, Cairns, QLD, Australia
- Garvin Institute of Medical Research, Darlinghurst, NSW, Australia
| | - Andreas Kupz
- Australian Institute of Tropical Health and Medicine, James Cook University, Cairns, QLD, Australia
- Centre for Molecular Therapeutics, James Cook University, Cairns, QLD, Australia
| | - Saparna Pai
- Australian Institute of Tropical Health and Medicine, James Cook University, Cairns, QLD, Australia
- Centre for Molecular Therapeutics, James Cook University, Cairns, QLD, Australia
| | - Dileep Sharma
- Australian Institute of Tropical Health and Medicine, James Cook University, Cairns, QLD, Australia
- College of Medicine & Dentistry, James Cook University, Cairns, QLD, Australia
| | - Michael J. Smout
- Australian Institute of Tropical Health and Medicine, James Cook University, Cairns, QLD, Australia
- Centre for Molecular Therapeutics, James Cook University, Cairns, QLD, Australia
| | - Phurpa Wangchuk
- Australian Institute of Tropical Health and Medicine, James Cook University, Cairns, QLD, Australia
- Centre for Molecular Therapeutics, James Cook University, Cairns, QLD, Australia
| | - Yide Wong
- Australian Institute of Tropical Health and Medicine, James Cook University, Cairns, QLD, Australia
- Centre for Tropical Bioinformatics and Molecular Biology, James Cook University, Cairns, QLD, Australia
- Centre for Molecular Therapeutics, James Cook University, Cairns, QLD, Australia
| | - Claire Loiseau
- Australian Institute of Tropical Health and Medicine, James Cook University, Cairns, QLD, Australia
- Centre for Molecular Therapeutics, James Cook University, Cairns, QLD, Australia
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14
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The yin and yang of human soil-transmitted helminth infections. Int J Parasitol 2021; 51:1243-1253. [PMID: 34774540 PMCID: PMC9145206 DOI: 10.1016/j.ijpara.2021.11.001] [Citation(s) in RCA: 26] [Impact Index Per Article: 8.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/08/2021] [Revised: 11/01/2021] [Accepted: 11/02/2021] [Indexed: 12/22/2022]
Abstract
The major soil-transmitted helminths that infect humans are the roundworms, whipworms and hookworms. Soil-transmitted helminth infections rank among the most important neglected tropical diseases in terms of morbidity, and almost one billion people are still infected with at least one species. While anthelmintic drugs are available, they do not offer long term protection against reinfection, precipitating the need for vaccines that provide long-term immunologic defense. Vaccine discovery and development is in advanced clinical development for hookworm infection, with a bivalent human hookworm vaccine in clinical trials in Brazil and Africa, but is in its infancy for both roundworm (ascariasis) and whipworm (trichuriasis) infections. One of the greatest hurdles to developing soil-transmitted helminth vaccines is the potent immunoregulatory properties of these helminths, creating a barrier to the induction of meaningful long-term protective immunity. While challenging for vaccinologists, this phenomenon presents unique opportunities to develop an entirely new class of anti-inflammatory drugs that capitalise on these immunomodulatory strategies. Epidemiologic studies and clinical trials employing experimental soil-transmitted helminth challenge models, when coupled with findings from animal models, show that at least some soil-transmitted helminth-derived molecules can protect against the onset of autoimmune, allergic and metabolic disorders, and several natural products with the desired bioactivity have been isolated and tested in pre-clinical settings. The yin and yang of soil-transmitted helminth infections reflect both the urgency for effective vaccines and the potential for new immunoregulatory molecules from parasite products.
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15
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Kropp PA, Bauer R, Zafra I, Graham C, Golden A. Caenorhabditis elegans for rare disease modeling and drug discovery: strategies and strengths. Dis Model Mech 2021; 14:dmm049010. [PMID: 34370008 PMCID: PMC8380043 DOI: 10.1242/dmm.049010] [Citation(s) in RCA: 15] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/14/2022] Open
Abstract
Although nearly 10% of Americans suffer from a rare disease, clinical progress in individual rare diseases is severely compromised by lack of attention and research resources compared to common diseases. It is thus imperative to investigate these diseases at their most basic level to build a foundation and provide the opportunity for understanding their mechanisms and phenotypes, as well as potential treatments. One strategy for effectively and efficiently studying rare diseases is using genetically tractable organisms to model the disease and learn about the essential cellular processes affected. Beyond investigating dysfunctional cellular processes, modeling rare diseases in simple organisms presents the opportunity to screen for pharmacological or genetic factors capable of ameliorating disease phenotypes. Among the small model organisms that excel in rare disease modeling is the nematode Caenorhabditis elegans. With a staggering breadth of research tools, C. elegans provides an ideal system in which to study human disease. Molecular and cellular processes can be easily elucidated, assayed and altered in ways that can be directly translated to humans. When paired with other model organisms and collaborative efforts with clinicians, the power of these C. elegans studies cannot be overstated. This Review highlights studies that have used C. elegans in diverse ways to understand rare diseases and aid in the development of treatments. With continuing and advancing technologies, the capabilities of this small round worm will continue to yield meaningful and clinically relevant information for human health.
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Affiliation(s)
| | | | | | | | - Andy Golden
- Laboratory of Biochemistry and Genetics, National Institute of Diabetes and Digestive and Kidney Diseases, National Institutes of Health, Bethesda, MD 20892, USA
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16
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High-content approaches to anthelmintic drug screening. Trends Parasitol 2021; 37:780-789. [PMID: 34092518 DOI: 10.1016/j.pt.2021.05.004] [Citation(s) in RCA: 6] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/02/2021] [Revised: 05/03/2021] [Accepted: 05/11/2021] [Indexed: 11/23/2022]
Abstract
Most anthelmintics were discovered through in vivo screens using animal models of infection. Developing in vitro assays for parasitic worms presents several challenges. The lack of in vitro life cycle culture protocols requires harvesting worms from vertebrate hosts or vectors, limiting assay throughput. Once worms are removed from the host environment, established anthelmintics often show no obvious phenotype - raising concerns about the predictive value of many in vitro assays. However, with recent progress in understanding how anthelmintics subvert host-parasite interactions, and breakthroughs in high-content imaging and machine learning, in vitro assays have the potential to discern subtle cryptic parasite phenotypes. These may prove better endpoints than conventional in vitro viability assays.
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17
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Partridge F, Bataille CJ, Forman R, Marriott AE, Forde-Thomas J, Häberli C, Dinsdale RL, O’Sullivan JD, Willis NJ, Wynne GM, Whiteland H, Archer J, Steven A, Keiser J, Turner JD, Hoffmann KF, Taylor MJ, Else KJ, Russell AJ, Sattelle DB. Structural Requirements for Dihydrobenzoxazepinone Anthelmintics: Actions against Medically Important and Model Parasites: Trichuris muris, Brugia malayi, Heligmosomoides polygyrus, and Schistosoma mansoni. ACS Infect Dis 2021; 7:1260-1274. [PMID: 33797218 PMCID: PMC8154432 DOI: 10.1021/acsinfecdis.1c00025] [Citation(s) in RCA: 7] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/15/2021] [Indexed: 02/07/2023]
Abstract
Nine hundred million people are infected with the soil-transmitted helminths Ascaris lumbricoides (roundworm), hookworm, and Trichuris trichiura (whipworm). However, low single-dose cure rates of the benzimidazole drugs, the mainstay of preventative chemotherapy for whipworm, together with parasite drug resistance, mean that current approaches may not be able to eliminate morbidity from trichuriasis. We are seeking to develop new anthelmintic drugs specifically with activity against whipworm as a priority and previously identified a hit series of dihydrobenzoxazepinone (DHB) compounds that block motility of ex vivo Trichuris muris. Here, we report a systematic investigation of the structure-activity relationship of the anthelmintic activity of DHB compounds. We synthesized 47 analogues, which allowed us to define features of the molecules essential for anthelmintic action as well as broadening the chemotype by identification of dihydrobenzoquinolinones (DBQs) with anthelmintic activity. We investigated the activity of these compounds against other parasitic nematodes, identifying DHB compounds with activity against Brugia malayi and Heligmosomoides polygyrus. We also demonstrated activity of DHB compounds against the trematode Schistosoma mansoni, a parasite that causes schistosomiasis. These results demonstrate the potential of DHB and DBQ compounds for further development as broad-spectrum anthelmintics.
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Affiliation(s)
- Frederick
A. Partridge
- Centre
for Respiratory Biology, UCL Respiratory, Division of Medicine, University College London, London WC1E 6JF, United Kingdom
| | - Carole J.R. Bataille
- Department
of Chemistry, Chemistry Research Laboratory, University of Oxford, Oxford OX1 3TA, United Kingdom
| | - Ruth Forman
- Lydia
Becker Institute of Immunology and Inflammation, Faculty of Biology,
Medicine and Health, University of Manchester, Manchester M13 9PT, United Kingdom
| | - Amy E. Marriott
- Centre
for Drugs and Diagnostics, Department of Tropical Disease Biology, Liverpool School of Tropical Medicine, Liverpool L3 5QA, United Kingdom
| | - Josephine Forde-Thomas
- Institute
of Biological, Environmental and Rural Sciences (IBERS), Aberystwyth University, Aberystwyth, Wales SY23 3DA, United Kingdom
| | - Cécile Häberli
- Department
of Medical Parasitology and Infection Biology, Swiss Tropical and Public Health Institute, Socinstrasse 57, Basel CH-4002, Switzerland
- University
of Basel, Petersplatz
1, Basel CH-4001, Switzerland
| | - Ria L. Dinsdale
- Department
of Chemistry, Chemistry Research Laboratory, University of Oxford, Oxford OX1 3TA, United Kingdom
| | - James D.B. O’Sullivan
- Lydia
Becker Institute of Immunology and Inflammation, Faculty of Biology,
Medicine and Health, University of Manchester, Manchester M13 9PT, United Kingdom
- Henry
Royce Institute, The University of Manchester, Oxford Road, Manchester M13 9PL, United
Kingdom
| | - Nicky J. Willis
- Department
of Chemistry, Chemistry Research Laboratory, University of Oxford, Oxford OX1 3TA, United Kingdom
- Alzheimer’s
Research UK UCL Drug Discovery Institute, University College London, Gower Street, London WC1E 6BT, United Kingdom
| | - Graham M. Wynne
- Department
of Chemistry, Chemistry Research Laboratory, University of Oxford, Oxford OX1 3TA, United Kingdom
| | - Helen Whiteland
- Institute
of Biological, Environmental and Rural Sciences (IBERS), Aberystwyth University, Aberystwyth, Wales SY23 3DA, United Kingdom
| | - John Archer
- Centre
for Drugs and Diagnostics, Department of Tropical Disease Biology, Liverpool School of Tropical Medicine, Liverpool L3 5QA, United Kingdom
| | - Andrew Steven
- Centre
for Drugs and Diagnostics, Department of Tropical Disease Biology, Liverpool School of Tropical Medicine, Liverpool L3 5QA, United Kingdom
| | - Jennifer Keiser
- Department
of Medical Parasitology and Infection Biology, Swiss Tropical and Public Health Institute, Socinstrasse 57, Basel CH-4002, Switzerland
- University
of Basel, Petersplatz
1, Basel CH-4001, Switzerland
| | - Joseph D. Turner
- Centre
for Drugs and Diagnostics, Department of Tropical Disease Biology, Liverpool School of Tropical Medicine, Liverpool L3 5QA, United Kingdom
- Centre
for Neglected Tropical Diseases, Liverpool
School of Tropical Medicine, Liverpool L3 5QA, United Kingdom
| | - Karl F. Hoffmann
- Institute
of Biological, Environmental and Rural Sciences (IBERS), Aberystwyth University, Aberystwyth, Wales SY23 3DA, United Kingdom
| | - Mark J. Taylor
- Centre
for Drugs and Diagnostics, Department of Tropical Disease Biology, Liverpool School of Tropical Medicine, Liverpool L3 5QA, United Kingdom
- Centre
for Neglected Tropical Diseases, Liverpool
School of Tropical Medicine, Liverpool L3 5QA, United Kingdom
| | - Kathryn J. Else
- Lydia
Becker Institute of Immunology and Inflammation, Faculty of Biology,
Medicine and Health, University of Manchester, Manchester M13 9PT, United Kingdom
| | - Angela J. Russell
- Department
of Chemistry, Chemistry Research Laboratory, University of Oxford, Oxford OX1 3TA, United Kingdom
- Department
of Pharmacology, University of Oxford, Mansfield Road, Oxford OX1 3QT, United
Kingdom
| | - David B. Sattelle
- Centre
for Respiratory Biology, UCL Respiratory, Division of Medicine, University College London, London WC1E 6JF, United Kingdom
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18
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Recombinant Paraprobiotics as a New Paradigm for Treating Gastrointestinal Nematode Parasites of Humans. Antimicrob Agents Chemother 2021; 65:AAC.01469-20. [PMID: 33318013 PMCID: PMC8092541 DOI: 10.1128/aac.01469-20] [Citation(s) in RCA: 7] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/10/2020] [Accepted: 12/08/2020] [Indexed: 12/11/2022] Open
Abstract
Gastrointestinal nematodes (GINs) of humans, e.g., hookworms, negatively impact childhood growth, cognition, nutrition, educational attainment, income, productivity, and pregnancy. Hundreds of millions of people are targeted with mass drug administration (MDA) of donated benzimidazole anthelmintics. Gastrointestinal nematodes (GINs) of humans, e.g., hookworms, negatively impact childhood growth, cognition, nutrition, educational attainment, income, productivity, and pregnancy. Hundreds of millions of people are targeted with mass drug administration (MDA) of donated benzimidazole anthelmintics. However, benzimidazole efficacy against GINs is suboptimal, and reduced/low efficacy has been seen. Developing an anthelmintic for human MDA is daunting: it must be safe, effective, inexpensive, stable without a cold chain, and massively scalable. Bacillus thuringiensis crystal protein 5B (Cry5B) has anthelmintic properties that could fill this void. Here, we developed an active pharmaceutical ingredient (API) containing B. thuringiensis Cry5B compatible with MDA. We expressed Cry5B in asporogenous B. thuringiensis during vegetative phase, forming cytosolic crystals. These bacteria with cytosolic crystals (BaCC) were rendered inviable (inactivated BaCC [IBaCC]) with food-grade essential oils. IBaCC potency was validated in vitro against nematodes. IBaCC was also potent in vivo against human hookworm infections in hamsters. IBaCC production was successfully scaled to 350 liters at a contract manufacturing facility. A simple fit-for-purpose formulation to protect against stomach digestion and powdered IBaCC were successfully made and used against GINs in hamsters and mice. A pilot histopathology study and blood chemistry workup showed that five daily consecutive doses of 200 mg/kg body weight Cry5B IBaCC (the curative single dose is 40 mg/kg) was nontoxic to hamsters and completely safe. IBaCC is a safe, inexpensive, highly effective, easy-to-manufacture, and scalable anthelmintic that is practical for MDA and represents a new paradigm for treating human GINs.
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Salikin NH, Nappi J, Majzoub ME, Egan S. Combating Parasitic Nematode Infections, Newly Discovered Antinematode Compounds from Marine Epiphytic Bacteria. Microorganisms 2020; 8:E1963. [PMID: 33322253 PMCID: PMC7764037 DOI: 10.3390/microorganisms8121963] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/04/2020] [Revised: 12/08/2020] [Accepted: 12/08/2020] [Indexed: 02/06/2023] Open
Abstract
Parasitic nematode infections cause debilitating diseases and impede economic productivity. Antinematode chemotherapies are fundamental to modern medicine and are also important for industries including agriculture, aquaculture and animal health. However, the lack of suitable treatments for some diseases and the rise of nematode resistance to many available therapies necessitates the discovery and development of new drugs. Here, marine epiphytic bacteria represent a promising repository of newly discovered antinematode compounds. Epiphytic bacteria are ubiquitous on marine surfaces where they are under constant pressure of grazing by bacterivorous predators (e.g., protozoans and nematodes). Studies have shown that these bacteria have developed defense strategies to prevent grazers by producing toxic bioactive compounds. Although several active metabolites against nematodes have been identified from marine bacteria, drug discovery from marine microorganisms remains underexplored. In this review, we aim to provide further insight into the need and potential for marine epiphytic bacteria to become a new source of antinematode drugs. We discuss current and emerging strategies, including culture-independent high throughput screening and the utilization of Caenorhabditis elegans as a model target organism, which will be required to advance antinematode drug discovery and development from marine microbial sources.
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Affiliation(s)
- Nor Hawani Salikin
- Centre for Marine Science and Innovation, School of Biological, Earth and Environmental Sciences, UNSW, Sydney, NSW 2052, Australia; (N.H.S.); (J.N.); (M.E.M.)
- School of Industrial Technology, Universiti Sains Malaysia, USM, 11800 Penang, Malaysia
| | - Jadranka Nappi
- Centre for Marine Science and Innovation, School of Biological, Earth and Environmental Sciences, UNSW, Sydney, NSW 2052, Australia; (N.H.S.); (J.N.); (M.E.M.)
| | - Marwan E. Majzoub
- Centre for Marine Science and Innovation, School of Biological, Earth and Environmental Sciences, UNSW, Sydney, NSW 2052, Australia; (N.H.S.); (J.N.); (M.E.M.)
| | - Suhelen Egan
- Centre for Marine Science and Innovation, School of Biological, Earth and Environmental Sciences, UNSW, Sydney, NSW 2052, Australia; (N.H.S.); (J.N.); (M.E.M.)
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Hahnel SR, Dilks CM, Heisler I, Andersen EC, Kulke D. Caenorhabditis elegans in anthelmintic research - Old model, new perspectives. INTERNATIONAL JOURNAL FOR PARASITOLOGY-DRUGS AND DRUG RESISTANCE 2020; 14:237-248. [PMID: 33249235 PMCID: PMC7704361 DOI: 10.1016/j.ijpddr.2020.09.005] [Citation(s) in RCA: 35] [Impact Index Per Article: 8.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 05/05/2020] [Revised: 09/25/2020] [Accepted: 09/26/2020] [Indexed: 12/13/2022]
Abstract
For more than four decades, the free-living nematode Caenorhabditis elegans has been extensively used in anthelmintic research. Classic genetic screens and heterologous expression in the C. elegans model enormously contributed to the identification and characterization of molecular targets of all major anthelmintic drug classes. Although these findings provided substantial insights into common anthelmintic mechanisms, a breakthrough in the treatment and control of parasitic nematodes is still not in sight. Instead, we are facing increasing evidence that the enormous diversity within the phylum Nematoda cannot be recapitulated by any single free-living or parasitic species and the development of novel broad-spectrum anthelmintics is not be a simple goal. In the present review, we summarize certain milestones and challenges of the C. elegans model with focus on drug target identification, anthelmintic drug discovery and identification of resistance mechanisms. Furthermore, we present new perspectives and strategies on how current progress in C. elegans research will support future anthelmintic research.
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Affiliation(s)
| | - Clayton M Dilks
- Northwestern University, Department of Molecular Biosciences, Evanston, IL, USA.
| | | | - Erik C Andersen
- Northwestern University, Department of Molecular Biosciences, Evanston, IL, USA.
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Partridge FA, Forman R, Bataille CJR, Wynne GM, Nick M, Russell AJ, Else KJ, Sattelle DB. Anthelmintic drug discovery: target identification, screening methods and the role of open science. Beilstein J Org Chem 2020; 16:1203-1224. [PMID: 32550933 PMCID: PMC7277699 DOI: 10.3762/bjoc.16.105] [Citation(s) in RCA: 20] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/30/2020] [Accepted: 05/12/2020] [Indexed: 12/13/2022] Open
Abstract
Helminths, including cestodes, nematodes and trematodes, are a huge global health burden, infecting hundreds of millions of people. In many cases, existing drugs such as benzimidazoles, diethylcarbamazine, ivermectin and praziquantel are insufficiently efficacious, contraindicated in some populations, or at risk of the development of resistance, thereby impeding progress towards World Health Organization goals to control or eliminate these neglected tropical diseases. However, there has been limited recent progress in developing new drugs for these diseases due to lack of commercial attractiveness, leading to the introduction of novel, more efficient models for drug innovation that attempt to reduce the cost of research and development. Open science aims to achieve this by encouraging collaboration and the sharing of data and resources between organisations. In this review we discuss how open science has been applied to anthelmintic drug discovery. Open resources, including genomic information from many parasites, are enabling the identification of targets for new antiparasitic agents. Phenotypic screening remains important, and there has been much progress in open-source systems for compound screening with parasites, including motility assays but also high content assays with more detailed investigation of helminth physiology. Distributed open science compound screening programs, such as the Medicines for Malaria Venture Pathogen Box, have been successful at facilitating screening in diverse assays against many different parasite pathogens and models. Of the compounds identified so far in these screens, tolfenpyrad, a repurposed insecticide, shows significant promise and there has been much progress in creating more potent and selective derivatives. This work exemplifies how open science approaches can catalyse drug discovery against neglected diseases.
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Affiliation(s)
- Frederick A Partridge
- Centre for Respiratory Biology, UCL Respiratory, Division of Medicine, University College London, Gower Street, London, WC1E 6BT, United Kingdom
| | - Ruth Forman
- The Lydia Becker Institute for Immunology and Inflammation, Faculty of Biology, Medicine and Health, University of Manchester, Oxford Road, Manchester, M13 9PL, United Kingdom
| | - Carole J R Bataille
- Department of Chemistry, Chemistry Research Laboratory, University of Oxford, 12 Mansfield Road, Oxford, OX1 3TA United Kingdom
| | - Graham M Wynne
- Department of Chemistry, Chemistry Research Laboratory, University of Oxford, 12 Mansfield Road, Oxford, OX1 3TA United Kingdom
| | - Marina Nick
- Centre for Respiratory Biology, UCL Respiratory, Division of Medicine, University College London, Gower Street, London, WC1E 6BT, United Kingdom
| | - Angela J Russell
- Department of Chemistry, Chemistry Research Laboratory, University of Oxford, 12 Mansfield Road, Oxford, OX1 3TA United Kingdom
- Department of Pharmacology, University of Oxford, Mansfield Road, Oxford, OX1 3QT, United Kingdom
| | - Kathryn J Else
- The Lydia Becker Institute for Immunology and Inflammation, Faculty of Biology, Medicine and Health, University of Manchester, Oxford Road, Manchester, M13 9PL, United Kingdom
| | - David B Sattelle
- Centre for Respiratory Biology, UCL Respiratory, Division of Medicine, University College London, Gower Street, London, WC1E 6BT, United Kingdom
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Sepúlveda-Crespo D, Reguera RM, Rojo-Vázquez F, Balaña-Fouce R, Martínez-Valladares M. Drug discovery technologies: Caenorhabditis elegans as a model for anthelmintic therapeutics. Med Res Rev 2020; 40:1715-1753. [PMID: 32166776 DOI: 10.1002/med.21668] [Citation(s) in RCA: 14] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/25/2019] [Revised: 12/10/2019] [Accepted: 02/26/2020] [Indexed: 12/16/2022]
Abstract
Helminthiasis is one of the gravest problems worldwide. There is a growing concern on less available anthelmintics and the emergence of resistance creating a major threat to human and livestock health resources. Novel and broad-spectrum anthelmintics are urgently needed. The free-living nematode Caenorhabditis elegans could address this issue through automated high-throughput technologies for the screening of large chemical libraries. This review discusses the strong advantages and limitations for using C elegans as a screening method for anthelmintic drug discovery. C elegans is the best model available for the validation of novel effective drugs in treating most, if not all, helminth infections, and for the elucidation the mode of action of anthelmintic candidates. This review also focuses on available technologies in the discovery of anthelmintics published over the last 15 years with particular attention to high-throughput technologies over conventional screens. On the other hand, this review highlights how combinatorial and nanomedicine strategies could prolong the use of anthelmintics and control resistance problems.
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Affiliation(s)
- Daniel Sepúlveda-Crespo
- Departamento de Ciencias Biomédicas, Facultad de Veterinaria, Universidad de León, León, Spain
| | - Rosa M Reguera
- Departamento de Ciencias Biomédicas, Facultad de Veterinaria, Universidad de León, León, Spain
| | - Francisco Rojo-Vázquez
- Instituto de Ganadería de Montaña (CSIC-Universidad de León), León, Spain.,Departamento de Sanidad Animal, Facultad de Veterinaria, Universidad de León, León, Spain
| | - Rafael Balaña-Fouce
- Departamento de Ciencias Biomédicas, Facultad de Veterinaria, Universidad de León, León, Spain
| | - María Martínez-Valladares
- Instituto de Ganadería de Montaña (CSIC-Universidad de León), León, Spain.,Departamento de Sanidad Animal, Facultad de Veterinaria, Universidad de León, León, Spain
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Liu M, Panda SK, Luyten W. Plant-Based Natural Products for the Discovery and Development of Novel Anthelmintics against Nematodes. Biomolecules 2020; 10:biom10030426. [PMID: 32182910 PMCID: PMC7175113 DOI: 10.3390/biom10030426] [Citation(s) in RCA: 35] [Impact Index Per Article: 8.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/21/2020] [Revised: 02/27/2020] [Accepted: 03/02/2020] [Indexed: 12/11/2022] Open
Abstract
Intestinal parasitic nematodes infect approximately two billion people worldwide. In the absence of vaccines for human intestinal nematodes, control of infections currently relies mainly on chemotherapy, but resistance is an increasing problem. Thus, there is an urgent need for the discovery and development of new anthelmintic drugs, especially ones with novel mechanisms of action. Medicinal plants hold great promise as a source of effective treatments, including anthelmintic therapy. They have been used traditionally for centuries and are mostly safe (if not, their toxicity is well-known). However, in most medicinal plants the compounds active against nematodes have not been identified thus far. The free-living nematode C. elegans was demonstrated to be an excellent model system for the discovery of new anthelmintics and for characterizing their mechanism of action or resistance. The compounds discussed in this review are of botanical origin and were published since 2002. Most of them need further studies of their toxicity, mechanisms and structure-activity relationship to assess more fully their potential as drugs.
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