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Leach J, Suber HN, Banks E, Kaskocsak A, Valencia H, Hames B, Rivera R, Colette S, Kendall RJ. In Vitro Lethality of Fenbendazole to the Eyeworm Oxyspirura petrowi. Animals (Basel) 2024; 14:1659. [PMID: 38891706 PMCID: PMC11171062 DOI: 10.3390/ani14111659] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/11/2024] [Revised: 04/12/2024] [Accepted: 04/18/2024] [Indexed: 06/21/2024] Open
Abstract
Oxyspirura petrowi is a heteroxenous nematode that infects the harderian gland and other ocular tissues in birds. High-intensity infections often cause damage to the infected tissues. Due to the nature of the infection sites, treatment of O. petrowi in these hosts can be difficult. Fenbendazole (FBZ) is a common anthelmintic used to treat birds for helminth infections; however, little information exists as to the efficacy of the drug on O. petrowi infections. The present study aims to estimate lethal concentrations of FBZ to O. petrowi. Adult O. petrowi were maintained in vitro and exposed to doses of 5, 50, 100, and 200 µM concentrations of FBZ and included both negative and vehicle controls. Exposure lasted 7.5 days and lethality was determined for each treatment. Negative and vehicle controls did not differ, and both had 75% survival at the end of the treatment period. The percentage survivorship in ascending order of concentration, corrected for the controls, was 66.67%, 44.44%, 33.33%, and 0%. LC10, LC50, and LC90 estimates were 7.5 ± 0.26, 49.1 ± 1.69, and 163.2 ± 5.63 µM, respectively. In the context of known pharmacokinetics of FBZ in birds, a single oral dose of FBZ can achieve exposure levels that are lethal to O. petrowi, but the drug does not stay in the system long enough. Thus, treatment of O. petrowi infections will require multiple oral doses over several days.
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Affiliation(s)
| | | | | | | | | | | | | | | | - Ronald J. Kendall
- Wildlife Toxicology Laboratory, Texas Tech University, 1234 Davis Dr., Lubbock, TX 79416, USA
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2
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Tyagi R, Rosa BA, Swain A, Artyomov MN, Jasmer DP, Mitreva M. Intestinal cell diversity and treatment responses in a parasitic nematode at single cell resolution. BMC Genomics 2024; 25:341. [PMID: 38575858 PMCID: PMC10996262 DOI: 10.1186/s12864-024-10203-7] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/08/2023] [Accepted: 03/08/2024] [Indexed: 04/06/2024] Open
Abstract
BACKGROUND Parasitic nematodes, significant pathogens for humans, animals, and plants, depend on diverse organ systems for intra-host survival. Understanding the cellular diversity and molecular variations underlying these functions holds promise for developing novel therapeutics, with specific emphasis on the neuromuscular system's functional diversity. The nematode intestine, crucial for anthelmintic therapies, exhibits diverse cellular phenotypes, and unraveling this diversity at the single-cell level is essential for advancing knowledge in anthelmintic research across various organ systems. RESULTS Here, using novel single-cell transcriptomics datasets, we delineate cellular diversity within the intestine of adult female Ascaris suum, a parasitic nematode species that infects animals and people. Gene transcripts expressed in individual nuclei of untreated intestinal cells resolved three phenotypic clusters, while lower stringency resolved additional subclusters and more potential diversity. Clusters 1 and 3 phenotypes displayed variable congruence with scRNA phenotypes of C. elegans intestinal cells, whereas the A. suum cluster 2 phenotype was markedly unique. Distinct functional pathway enrichment characterized each A. suum intestinal cell cluster. Cluster 2 was distinctly enriched for Clade III-associated genes, suggesting it evolved within clade III nematodes. Clusters also demonstrated differential transcriptional responsiveness to nematode intestinal toxic treatments, with Cluster 2 displaying the least responses to short-term intra-pseudocoelomic nematode intestinal toxin treatments. CONCLUSIONS This investigation presents advances in knowledge related to biological differences among major cell populations of adult A. suum intestinal cells. For the first time, diverse nematode intestinal cell populations were characterized, and associated biological markers of these cells were identified to support tracking of constituent cells under experimental conditions. These advances will promote better understanding of this and other parasitic nematodes of global importance, and will help to guide future anthelmintic treatments.
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Affiliation(s)
- Rahul Tyagi
- Division of Infectious Diseases, Department of Internal Medicine, Washington University School of Medicine, 63110, St. Louis, MO, USA
| | - Bruce A Rosa
- Division of Infectious Diseases, Department of Internal Medicine, Washington University School of Medicine, 63110, St. Louis, MO, USA
| | - Amanda Swain
- Department of Pathology and Immunology, Washington University School of Medicine, 63110, Saint Louis, MO, USA
| | - Maxim N Artyomov
- Department of Pathology and Immunology, Washington University School of Medicine, 63110, Saint Louis, MO, USA
| | - Douglas P Jasmer
- Department of Veterinary Microbiology and Pathology, Washington State University, 99164, Pullman, WA, USA.
| | - Makedonka Mitreva
- Division of Infectious Diseases, Department of Internal Medicine, Washington University School of Medicine, 63110, St. Louis, MO, USA.
- Department of Genetics, Washington University School of Medicine, 63110, St. Louis, MO, USA.
- McDonnell Genome Institute, Washington University School of Medicine, 63110, St Louis, MO, USA.
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3
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Gibson SB, Ness-Cohn E, Andersen EC. Benzimidazoles cause lethality by inhibiting the function of Caenorhabditis elegans neuronal beta-tubulin. Int J Parasitol Drugs Drug Resist 2022; 20:89-96. [PMID: 36332489 PMCID: PMC9771835 DOI: 10.1016/j.ijpddr.2022.10.004] [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: 07/19/2022] [Revised: 10/17/2022] [Accepted: 10/18/2022] [Indexed: 11/08/2022]
Abstract
Parasitic nematode infections cause an enormous global burden to both humans and livestock. Resistance to the limited arsenal of anthelmintic drugs used to combat these infections is widespread, including benzimidazole (BZ) compounds. Previous studies using the free-living nematode Caenorhabditis elegans to model parasitic nematode resistance have shown that loss-of-function mutations in the beta-tubulin gene ben-1 confer resistance to BZ drugs. However, the mechanism of resistance and the tissue-specific susceptibility are not well known in any nematode species. To identify in which tissue(s) ben-1 function underlies BZ susceptibility, transgenic strains that express ben-1 in different tissues, including hypodermis, muscles, neurons, intestine, and ubiquitous expression were generated. High-throughput fitness assays were performed to measure and compare the quantitative responses to BZ compounds among different transgenic lines. Significant BZ susceptibility was observed in animals expressing ben-1 in neurons, comparable to expression using the ben-1 promoter. This result suggests that ben-1 function in neurons underlies susceptibility to BZ. Subsetting neuronal expression of ben-1 based on the neurotransmitter system further restricted ben-1 function in cholinergic neurons to cause BZ susceptibility. These results better inform our current understanding of the cellular mode of action of BZs and also suggest additional treatments that might potentiate the effects of BZs in neurons.
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Affiliation(s)
- Sophia B. Gibson
- Department of Molecular Biosciences, Northwestern University, Evanston, IL, 60208, USA
| | - Elan Ness-Cohn
- Department of Molecular Biosciences, Northwestern University, Evanston, IL, 60208, USA,Driskill Graduate Program in Life Sciences, Northwestern University, Chicago, IL, 60611, USA
| | - Erik C. Andersen
- Department of Molecular Biosciences, Northwestern University, Evanston, IL, 60208, USA,Corresponding author. Department of Molecular Biosciences Northwestern University 4619 Silverman Hall 2205 Tech Drive Evanston, IL, 60208, USA.
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4
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Doyle SR, Laing R, Bartley D, Morrison A, Holroyd N, Maitland K, Antonopoulos A, Chaudhry U, Flis I, Howell S, McIntyre J, Gilleard JS, Tait A, Mable B, Kaplan R, Sargison N, Britton C, Berriman M, Devaney E, Cotton JA. Genomic landscape of drug response reveals mediators of anthelmintic resistance. Cell Rep 2022; 41:111522. [PMID: 36261007 PMCID: PMC9597552 DOI: 10.1016/j.celrep.2022.111522] [Citation(s) in RCA: 15] [Impact Index Per Article: 7.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/18/2022] [Revised: 07/11/2022] [Accepted: 09/26/2022] [Indexed: 11/18/2022] Open
Abstract
Like other pathogens, parasitic helminths can rapidly evolve resistance to drug treatment. Understanding the genetic basis of anthelmintic drug resistance in parasitic nematodes is key to tracking its spread and improving the efficacy and sustainability of parasite control. Here, we use an in vivo genetic cross between drug-susceptible and multi-drug-resistant strains of Haemonchus contortus in a natural host-parasite system to simultaneously map resistance loci for the three major classes of anthelmintics. This approach identifies new alleles for resistance to benzimidazoles and levamisole and implicates the transcription factor cky-1 in ivermectin resistance. This gene is within a locus under selection in ivermectin-resistant populations worldwide; expression analyses and functional validation using knockdown experiments support that cky-1 is associated with ivermectin survival. Our work demonstrates the feasibility of high-resolution forward genetics in a parasitic nematode and identifies variants for the development of molecular diagnostics to combat drug resistance in the field.
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Affiliation(s)
- Stephen R Doyle
- Wellcome Sanger Institute, Hinxton, Cambridgeshire CB10 1SA, UK.
| | - Roz Laing
- Institute of Biodiversity Animal Health and Comparative Medicine, College of Medical, Veterinary and Life Sciences, University of Glasgow, Glasgow G61 1QH, UK.
| | - David Bartley
- Moredun Research Institute, Penicuik, Midlothian EH26 0PZ, UK
| | - Alison Morrison
- Moredun Research Institute, Penicuik, Midlothian EH26 0PZ, UK
| | - Nancy Holroyd
- Wellcome Sanger Institute, Hinxton, Cambridgeshire CB10 1SA, UK
| | - Kirsty Maitland
- Institute of Biodiversity Animal Health and Comparative Medicine, College of Medical, Veterinary and Life Sciences, University of Glasgow, Glasgow G61 1QH, UK
| | - Alistair Antonopoulos
- Institute of Biodiversity Animal Health and Comparative Medicine, College of Medical, Veterinary and Life Sciences, University of Glasgow, Glasgow G61 1QH, UK
| | - Umer Chaudhry
- Royal (Dick) School of Veterinary Studies, University of Edinburgh, Edinburgh EH25 9RG, UK
| | - Ilona Flis
- Institute of Biodiversity Animal Health and Comparative Medicine, College of Medical, Veterinary and Life Sciences, University of Glasgow, Glasgow G61 1QH, UK
| | - Sue Howell
- Department of Infectious Diseases, College of Veterinary Medicine, University of Georgia, Athens, GA 30602, USA
| | - Jennifer McIntyre
- Institute of Biodiversity Animal Health and Comparative Medicine, College of Medical, Veterinary and Life Sciences, University of Glasgow, Glasgow G61 1QH, UK
| | - John S Gilleard
- Department of Comparative Biology and Experimental Medicine, Host-Parasite Interactions Program, Faculty of Veterinary Medicine, University of Calgary, Calgary T2N 1N4, Canada
| | - Andy Tait
- Institute of Biodiversity Animal Health and Comparative Medicine, College of Medical, Veterinary and Life Sciences, University of Glasgow, Glasgow G61 1QH, UK
| | - Barbara Mable
- Institute of Biodiversity Animal Health and Comparative Medicine, College of Medical, Veterinary and Life Sciences, University of Glasgow, Glasgow G61 1QH, UK
| | - Ray Kaplan
- Department of Infectious Diseases, College of Veterinary Medicine, University of Georgia, Athens, GA 30602, USA
| | - Neil Sargison
- Royal (Dick) School of Veterinary Studies, University of Edinburgh, Edinburgh EH25 9RG, UK
| | - Collette Britton
- Institute of Biodiversity Animal Health and Comparative Medicine, College of Medical, Veterinary and Life Sciences, University of Glasgow, Glasgow G61 1QH, UK
| | | | - Eileen Devaney
- Institute of Biodiversity Animal Health and Comparative Medicine, College of Medical, Veterinary and Life Sciences, University of Glasgow, Glasgow G61 1QH, UK
| | - James A Cotton
- Wellcome Sanger Institute, Hinxton, Cambridgeshire CB10 1SA, UK
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5
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Chen C, Ding Y, Liu H, Sun M, Wang H, Wu D. Flubendazole Plays an Important Anti-Tumor Role in Different Types of Cancers. Int J Mol Sci 2022; 23:ijms23010519. [PMID: 35008943 PMCID: PMC8745596 DOI: 10.3390/ijms23010519] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/29/2021] [Revised: 12/30/2021] [Accepted: 01/01/2022] [Indexed: 02/01/2023] Open
Abstract
Flubendazole, belonging to benzimidazole, is a broad-spectrum insect repellent and has been repurposed as a promising anticancer drug. In recent years, many studies have shown that flubendazole plays an anti-tumor role in different types of cancers, including breast cancer, melanoma, prostate cancer, colorectal cancer, and lung cancer. Although the anti-tumor mechanism of flubendazole has been studied, it has not been fully understood. In this review, we summarized the recent studies regarding the anti-tumor effects of flubendazole in different types of cancers and analyzed the related mechanisms, in order to provide the theoretical reference for further studies in the future.
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Affiliation(s)
- Chaoran Chen
- Institute of Nursing and Health, School of Nursing and Health, Henan University, Jinming Avenue, Kaifeng 475004, China; (C.C.); (Y.D.)
| | - Yueming Ding
- Institute of Nursing and Health, School of Nursing and Health, Henan University, Jinming Avenue, Kaifeng 475004, China; (C.C.); (Y.D.)
| | - Huiyang Liu
- Henan International Joint Laboratory of Nuclear Protein Regulation, School of Basic Medical Sciences, Henan University, Kaifeng 475004, China;
| | - Mengyao Sun
- School of Clinical Medicine, Henan University, Kaifeng 475004, China;
| | - Honggang Wang
- Henan International Joint Laboratory of Nuclear Protein Regulation, School of Basic Medical Sciences, Henan University, Kaifeng 475004, China;
- Correspondence: (H.W.); (D.W.)
| | - Dongdong Wu
- Henan International Joint Laboratory of Nuclear Protein Regulation, School of Basic Medical Sciences, Henan University, Kaifeng 475004, China;
- School of Stomatology, Henan University, Kaifeng 475004, China
- Correspondence: (H.W.); (D.W.)
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6
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Jasmer DP, Rosa BA, Tyagi R, Mitreva M. Rapid determination of nematode cell and organ susceptibility to toxic treatments. INTERNATIONAL JOURNAL FOR PARASITOLOGY-DRUGS AND DRUG RESISTANCE 2020; 14:167-182. [PMID: 33125935 PMCID: PMC7593349 DOI: 10.1016/j.ijpddr.2020.10.007] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 08/07/2020] [Revised: 10/16/2020] [Accepted: 10/19/2020] [Indexed: 12/28/2022]
Abstract
In research focused on the intestine of parasitic nematodes, we recently identified small molecule inhibitors toxic to intestinal cells of larval Ascaris suum (nematode intestinal toxins/toxicants; “NITs”). Some NITs had anthelmintic activity across the phylogenetic diversity of the Nematoda. The whole-worm motility inhibition assay quantified anthelmintic activity, but worm responses to NITs in relation to pathology or affected molecular pathways was not acquired. In this study we extended this research to more comprehensively determine in whole larval A. suum the cells, organ systems, molecular targets, and potential cellular pathways involved in mechanisms of toxicity leading to cell death. The experimental system utilized fluorescent nuclear probes (bisbenzimide, propidium iodide), NITs, an A. suum larval parasite culture system and transcriptional responses (RNA-seq) to NITs. The approach provides for rapid resolution of NIT-induced cell death among organ systems (e.g. intestine, excretory, esophagus, hypodermis and seam cells, and nervous), discriminates among NITs based on cell death profiles, and identifies cells and organ systems with the greatest NIT sensitivity (e.g. intestine and apparent neuronal cells adjacent to the nerve ring). Application was extended to identify cells and organs sensitive to several existing anthelmintics. This approach also resolved intestinal cell death and irreparable damage induced in adult A. suum by two NITs, establishing a new model to elucidate relevant pathologic mechanisms in adult worms. RNA-seq analysis resolved A. suum genes responsive to treatments with three NITs, identifying dihydroorotate dehydrogenase (uridine synthesis) and RAB GTPase(s) (vesicle transport) as potential targets/pathways leading to cell death. A set of genes induced by all three NITs tested suggest common stress or survival responses activated by NITs. Beyond the presented specific lines of research, elements of the overall experimental system presented in this study have broad application toward systematic development of new anthelmintics. A unique rapid cell death assay was developed for parasitic nematodes. Multiple drug-like molecules cause widespread cell death in many organs of A. suum. Multiple cell and organ systems were validated as targets for anthelmintics. Potential drug targets/pathways were implicated in activating cell death processes.
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Affiliation(s)
- Douglas P Jasmer
- Department of Veterinary Microbiology and Pathology, Washington State University, Pullman, WA, 99164, USA
| | - Bruce A Rosa
- Division of Infectious Diseases, Department of Medicine, Washington University School of Medicine, St. Louis, MO, 63110, USA
| | - Rahul Tyagi
- Division of Infectious Diseases, Department of Medicine, Washington University School of Medicine, St. Louis, MO, 63110, USA
| | - Makedonka Mitreva
- Division of Infectious Diseases, Department of Medicine, Washington University School of Medicine, St. Louis, MO, 63110, USA; Department of Genetics, Washington University School of Medicine, St. Louis, MO 63110, St. Louis, MO, 63110, USA; McDonnell Genome Institute, Washington University School of Medicine, St. Louis, Missouri, 63108, USA.
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7
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Albendazole-Induced SIRT3 Upregulation Protects Human Leukemia K562 Cells from the Cytotoxicity of MCL1 Suppression. Int J Mol Sci 2020; 21:ijms21113907. [PMID: 32486166 PMCID: PMC7312678 DOI: 10.3390/ijms21113907] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/24/2020] [Revised: 05/20/2020] [Accepted: 05/29/2020] [Indexed: 12/20/2022] Open
Abstract
Previous studies have shown that MCL1 stabilization confers cancer cells resistance to microtubule targeting agents (MTAs) and functionally extends the lifespan of MTA-triggered mitotically arrested cells. Albendazole (ABZ), a benzimidazole anthelmintic, shows microtubule-destabilizing activity and has been repositioned for cancer therapies. To clarify the role of MCL1 in ABZ-induced apoptosis, we investigated the cytotoxicity of ABZ on human leukemia K562 cells. Treatment with ABZ for 24 h did not appreciably induce apoptosis or mitochondrial depolarization in K562 cells, though it caused the mitotic arrest of K562 cells. ABZ-evoked p38 MAPK activation concurrently suppressed Sp1-mediated MCL1 expression and increased SIRT3 mRNA stability and protein expression. ABZ and A-1210477 (an MCL1 inhibitor) enhanced the cytotoxicity of ABT-263 (a BCL2/BCL2L1 inhibitor) to their effect on MCL1 suppression. Unlike ABZ, A-1210477 did not affect SIRT3 expression and reduced the survival of K562 cells. Overexpression of SIRT3 attenuated the A-1210477 cytotoxicity on K562 cells. ABZ treatment elicited marked apoptosis and ΔΨm loss in ABT-263-resistant K562 (K562/R) cells, but did not alter SIRT3 expression. Ectopic expression of SIRT3 alleviated the cytotoxicity of ABZ on K562/R cells. Collectively, our data demonstrate that ABZ-induced SIRT3 upregulation delays the apoptosis-inducing effect of MCL1 suppression on apoptosis induction in K562 cells.
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8
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Jasmer DP, Rosa BA, Tyagi R, Bulman CA, Beerntsen B, Urban JF, Sakanari J, Mitreva M. De novo identification of toxicants that cause irreparable damage to parasitic nematode intestinal cells. PLoS Negl Trop Dis 2020; 14:e0007942. [PMID: 32453724 PMCID: PMC7274465 DOI: 10.1371/journal.pntd.0007942] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/13/2019] [Revised: 06/05/2020] [Accepted: 05/04/2020] [Indexed: 02/06/2023] Open
Abstract
Efforts to identify new drugs for therapeutic and preventive treatments against parasitic nematodes have gained increasing interest with expanding pathogen omics databases and drug databases from which new anthelmintic compounds might be identified. Here, a novel approach focused on integrating a pan-Nematoda multi-omics data targeted to a specific nematode organ system (the intestinal tract) with evidence-based filtering and chemogenomic screening was undertaken. Based on de novo computational target prioritization of the 3,564 conserved intestine genes in A. suum, exocytosis was identified as a high priority pathway, and predicted inhibitors of exocytosis were tested using the large roundworm (Ascaris suum larval stages), a filarial worm (Brugia pahangi adult and L3), a whipworm (Trichuris muris adult), and the non-parasitic nematode Caenorhabditis elegans. 10 of 13 inhibitors were found to cause rapid immotility in A. suum L3 larvae, and five inhibitors were effective against the three phylogenetically diverse parasitic nematode species, indicating potential for a broad spectrum anthelmintics. Several distinct pathologic phenotypes were resolved related to molting, motility, or intestinal cell and tissue damage using conventional and novel histologic methods. Pathologic profiles characteristic for each inhibitor will guide future research to uncover mechanisms of the anthelmintic effects and improve on drug designs. This progress firmly validates the focus on intestinal cell biology as a useful resource to develop novel anthelmintic strategies.
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Affiliation(s)
- Douglas P Jasmer
- Department of Veterinary Microbiology and Pathology, Washington State University, Pullman, Washington, United States of America
| | - Bruce A Rosa
- Division of Infectious Diseases, Department of Medicine, Washington University School of Medicine, St. Louis, Missouri, United States of America
| | - Rahul Tyagi
- McDonnell Genome Institute, Washington University School of Medicine, St. Louis, Missouri, United States of America
| | - Christina A Bulman
- Department of Pharmaceutical Chemistry, University of California San Francisco, San Francisco, California, United States of America
| | - Brenda Beerntsen
- Department of Veterinary Pathobiology, University of Missouri, Columbia, Missouri, United States of America
| | - Joseph F Urban
- U.S. Department of Agriculture, Northeast Area, Agricultural Research Service, Beltsville Agricultural Research Center, Animal Parasite Diseases Laboratory and Beltsville Human Nutrition Research Center, Diet Genomics and Immunology Laboratory, Beltsville, Maryland, United States of America
| | - Judy Sakanari
- Department of Pharmaceutical Chemistry, University of California San Francisco, San Francisco, California, United States of America
| | - Makedonka Mitreva
- Division of Infectious Diseases, Department of Medicine, Washington University School of Medicine, St. Louis, Missouri, United States of America.,McDonnell Genome Institute, Washington University School of Medicine, St. Louis, Missouri, United States of America
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9
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Zuo M, Guo W, Pang Y, Guo R, Hou C, Sun S, Wu H, Sun Z, Chu W. Direct synthesis of 2-substituted benzimidazoles via dehydrogenative coupling of aromatic-diamine and primary alcohol catalyzed by a Co complex. NEW J CHEM 2020. [DOI: 10.1039/d0nj03619f] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/19/2022]
Abstract
A Co(ii) complex was synthesized and used as catalyst to synthesize a series of 2-substituted benzimidazoles with o-phenylenediamines and primary alcohol as the substrates under mild reaction conditions.
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Affiliation(s)
- Minghui Zuo
- School of Chemistry and Materials Science
- Heilongjiang University
- Harbin 150080
- P. R. China
- Key Laboratory of Chemical Engineering Process and Technology for High-efficiency Conversion
| | - Weihao Guo
- School of Chemistry and Materials Science
- Heilongjiang University
- Harbin 150080
- P. R. China
- Key Laboratory of Chemical Engineering Process and Technology for High-efficiency Conversion
| | - Yucheng Pang
- School of Chemistry and Materials Science
- Heilongjiang University
- Harbin 150080
- P. R. China
- Key Laboratory of Chemical Engineering Process and Technology for High-efficiency Conversion
| | - Rui Guo
- School of Chemistry and Materials Science
- Heilongjiang University
- Harbin 150080
- P. R. China
- Key Laboratory of Chemical Engineering Process and Technology for High-efficiency Conversion
| | - Chuanfu Hou
- School of Chemistry and Materials Science
- Heilongjiang University
- Harbin 150080
- P. R. China
- Key Laboratory of Chemical Engineering Process and Technology for High-efficiency Conversion
| | - Shouneng Sun
- School of Chemistry and Materials Science
- Heilongjiang University
- Harbin 150080
- P. R. China
- Key Laboratory of Chemical Engineering Process and Technology for High-efficiency Conversion
| | - Hongfeng Wu
- School of Chemistry and Materials Science
- Heilongjiang University
- Harbin 150080
- P. R. China
- Key Laboratory of Chemical Engineering Process and Technology for High-efficiency Conversion
| | - Zhizhong Sun
- School of Chemistry and Materials Science
- Heilongjiang University
- Harbin 150080
- P. R. China
- Key Laboratory of Chemical Engineering Process and Technology for High-efficiency Conversion
| | - Wenyi Chu
- School of Chemistry and Materials Science
- Heilongjiang University
- Harbin 150080
- P. R. China
- Key Laboratory of Chemical Engineering Process and Technology for High-efficiency Conversion
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10
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Adamu M, Mukandiwa L, Awouafack MD, Ahmed AS, Eloff JN, Naidoo V. Ultrastructure changes induced by the phloroglucinol derivative agrimol G isolated from Leucosidea sericea in Haemonchus contortus. Exp Parasitol 2019; 207:107780. [PMID: 31629699 DOI: 10.1016/j.exppara.2019.107780] [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: 07/03/2019] [Revised: 09/12/2019] [Accepted: 10/14/2019] [Indexed: 10/25/2022]
Abstract
Plant extracts used for the treatment of helminth infections in sheep are an alternative to chemical anthelmintic drugs. Previous studies have reported the anthelmintic activity of acetone leaf extracts of Leucosidea sericea. For this study, we evaluate the ultrastructure changes induced by the acetone leaf extract of L. sericea and the component agrimol G (AG) that was isolated for the first time on adult haemonchus parasites. Adult haemonchus parasites harvested from sheep were incubated with the plant extract and AG for 3 h and evaluated by both scanning and transmission electron microscopy in comparison and in combination with albendazole or ivermectin. In all cases the method of evaluation shows ultrastructural changes, with albendazole inducing mitochondrial damage and ivermectin inducing muscle degeneration, both as previously described. Incubation with the plant extract and AG resulted in the formation of numerous non-membrane bound multi-vesicular like bodies and evenly spread disruptions/erosion in the epicuticle. Combining AG with ivermectin or albendazole resulted in an absence of effect of AG. Based on the structural changes induced by AG, together with the absence of an effect in combination with ivermectin and albendazole would suggest a disrupted microtubular network. The latter does however require biochemical confirmation.
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Affiliation(s)
- M Adamu
- Department of Paraclinical Sciences, Faculty of Veterinary Science, University of Pretoria, South Africa
| | - L Mukandiwa
- Department of Paraclinical Sciences, Faculty of Veterinary Science, University of Pretoria, South Africa; Biomedical Research Centre, Faculty of Veterinary Science, University of Pretoria, South Africa
| | - M D Awouafack
- Department of Paraclinical Sciences, Faculty of Veterinary Science, University of Pretoria, South Africa
| | - A S Ahmed
- Department of Paraclinical Sciences, Faculty of Veterinary Science, University of Pretoria, South Africa
| | - J N Eloff
- Department of Paraclinical Sciences, Faculty of Veterinary Science, University of Pretoria, South Africa
| | - V Naidoo
- Department of Paraclinical Sciences, Faculty of Veterinary Science, University of Pretoria, South Africa; Biomedical Research Centre, Faculty of Veterinary Science, University of Pretoria, South Africa.
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11
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Jasmer DP, Rosa BA, Tyagi R, Mitreva M. Omics Driven Understanding of the Intestines of Parasitic Nematodes. Front Genet 2019; 10:652. [PMID: 31402928 PMCID: PMC6669237 DOI: 10.3389/fgene.2019.00652] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/06/2019] [Accepted: 06/19/2019] [Indexed: 01/25/2023] Open
Abstract
The biological and molecular complexity of nematodes has impeded research on development of new therapies for treatment and control. We have focused on the versatility of the nematode intestine as a target for new therapies. To that end, it is desirable to establish a broad and deep understanding of the molecular architecture underlying intestinal cell functions at the pan-Nematoda level. Multiomics data were generated to uncover the evolutionary principles underlying both conserved and adaptable features of the nematode intestine. Whole genomes were used to reveal the functional potential of the nematodes, tissue-specific transcriptomes provided a deep assessment of genes that are expressed in the adult nematode intestine, and comparison of selected core species was used to determine a first approximation of the pan-Nematoda intestinal transcriptome. Differentially expressed transcripts were also identified among intestinal regions, with the largest number expressed at significantly higher levels in the anterior region, identifying this region as the most functionally unique compared to middle and posterior regions. Profiling intestinal miRNAs targeting these genes identified the conserved intestinal miRNAs. Proteomics of intestinal cell compartments assigned proteins to several different intestinal cell compartments (intestinal tissue, the integral and peripheral intestinal membranes, and the intestinal lumen). Finally, advanced bioinformatic approaches were used to predict intestinal cell functional categories of seminal importance to parasite survival, which can now be experimentally tested and validated. The data provide the most comprehensive compilation of constitutively and differentially expressed genes, predicted gene regulators, and proteins of the nematode intestine. The information provides knowledge that is essential to understand molecular features of nematode intestinal cells and functions of fundamental importance to the intestine of many, if not all, parasitic nematodes.
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Affiliation(s)
- Douglas P Jasmer
- Department of Veterinary Microbiology and Pathology, Washington State University, Pullman, WA, United States
| | - Bruce A Rosa
- McDonnell Genome Institute, Washington University, St. Louis, St. Louis, MI, United States
| | - Rahul Tyagi
- McDonnell Genome Institute, Washington University, St. Louis, St. Louis, MI, United States
| | - Makedonka Mitreva
- McDonnell Genome Institute, Washington University, St. Louis, St. Louis, MI, United States.,Department of Internal Medicine, Washington University School of Medicine, St. Louis, MI, United States
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12
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In vitro efficacies of solubility-improved mebendazole derivatives against Echinococcus multilocularis. Parasitology 2019; 146:1256-1262. [DOI: 10.1017/s0031182019000386] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/03/2023]
Abstract
AbstractRecently, we introduced an epoxy group to mebendazole by a reaction with epichlorohydrin and obtained two isoforms, mebendazole C1 (M-C1) and mebendazole C2 (M-C2). The in vitro effects of mebendazole derivatives at different concentrations on Echinococcus multilocularis protoscoleces and metacestodes as well as cytotoxicity in rat hepatoma (RH) cells were examined. The results demonstrated that the solubility of the two derivatives was greatly improved compared to mebendazole. The mortality of protoscoleces in vitro reached to 70–80% after 7 days of exposure to mebendazole or M-C2, and M-C2 showed higher parasiticidal effects than mebendazole (P > 0.05). The parasiticidal effect of M-C1 was low, even at a concentration of 30 µm. The percentage of damaged metacestodes that were treated with mebendazole and M-C2 in vitro at different concentrations were similar, and M-C1 exhibited insignificant effects on metacestodes. Significant morphological changes on protoscoleces and metacestodes were observed after treatment with mebendazole and M-C2. In addition, the introduction of an epoxy group to mebendazole also reduced its cytotoxicity in RH cells. Our results demonstrate that the introduction of an epoxy group not only improved the solubility of mebendazole, but also increased its parasiticidal effects on E. multilocularis and reduced its cytotoxicity in RH cells.
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13
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Non-mitotic effect of albendazole triggers apoptosis of human leukemia cells via SIRT3/ROS/p38 MAPK/TTP axis-mediated TNF-α upregulation. Biochem Pharmacol 2019; 162:154-168. [DOI: 10.1016/j.bcp.2018.11.003] [Citation(s) in RCA: 30] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/16/2018] [Accepted: 11/05/2018] [Indexed: 12/27/2022]
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Carneiro MB, Avelar BR, Archanjo AB, Martins IVF, Nunes LDC, Scott FB. Microscopic alterations in Fasciola hepatica from sheep treated with albendazole. ACTA ACUST UNITED AC 2019; 28:33-39. [PMID: 30785554 DOI: 10.1590/s1984-296120180095] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/27/2018] [Accepted: 11/26/2018] [Indexed: 11/22/2022]
Abstract
Currently, albendazole is one of the most commonly used drugs because of its affordability. The objective was to evaluate the histopathology of Fasciola hepatica specimens. For this, the efficacy test was performed on sheep treated with albendazole at the dose recommended for F. hepatica, in which the helminths recovered at necropsy were counted and separated for histology. Spermatogenic cells from parasites recovered from treated and control sheep were examined by microscopy. The fecal egg-count reduction test revealed 97.06% efficacy of albendazole in the treatment of F. hepatica. Changes in testicular tubule cells started 48 hours after treatment and became evident within 72 hours, at which point it became difficult to identify cell types. Primary and secondary spermatogonia became increasingly rare and intercellular vacuolization was more evident. Signs of apoptosis, with pycnotic nuclei and evidence of keriorrexia were observed at all times. Cell debris was identified 96 hours after treatment. The results indicated that parasitic spermatogenesis was severely affected by albendazole and demonstrated the importance of the use of histopathology for the diagnosis of therapeutic efficacy in field strains.
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Affiliation(s)
- Milena Batista Carneiro
- Programa de Pós-graduação em Ciências Veterinárias, Universidade Federal Rural do Rio de Janeiro - UFRRJ, Seropédica, RJ, Brasil
| | - Barbara Rauta Avelar
- Programa de Pós-graduação em Ciências Veterinárias, Universidade Federal do Espírito Santo - UFES, Alegre, ES, Brasil
| | - Anderson Barros Archanjo
- Programa de Pós-graduação em Biotecnologia, Universidade Federal do Espírito Santo - UFES, Vitória, ES, Brasil
| | - Isabella Vilhena Freire Martins
- Departamento de Medicina Veterinária, Centro de Ciências Agrárias e Engenharias, Universidade Federal do Espírito Santo - UFES, Alegre, ES, Brasil
| | - Louisiane de Carvalho Nunes
- Laboratório de Patologia Animal, Departamento de Medicina Veterinária, Universidade Federal do Espírito Santo - UFES, Alegre, ES, Brasil
| | - Fabio Barbour Scott
- Departamento de Parasitologia Animal, Instituto de Veterinária, Universidade Federal Rural do Rio de Janeiro - UFRRJ, Seropédica, RJ, Brasil
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Raisová Stuchlíková L, Králová V, Lněničková K, Zárybnický T, Matoušková P, Hanušová V, Ambrož M, Šubrt Z, Skálová L. The metabolism of flubendazole in human liver and cancer cell lines. Drug Test Anal 2018; 10:1139-1146. [PMID: 29426058 DOI: 10.1002/dta.2369] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/09/2017] [Revised: 01/29/2018] [Accepted: 01/30/2018] [Indexed: 11/06/2022]
Abstract
Flubendazole (FLU), a benzimidazole anthelmintic drug widely used in veterinary medicine, has been approved for the treatment of gut-residing nematodes in humans. In addition, FLU is now considered a promising anti-cancer agent. Despite this, information about biotransformation of this compound in human is lacking. Moreover, there is no information regarding whether cancer cells are able to metabolize FLU in order to deactivate it. For these reasons, the present study was designed to identify all metabolites of Phase I and Phase II of FLU in human liver and in various cancer cells using ultra high-performance liquid chromatography-tandem mass spectrometry (UHPLC-MS/MS) analysis. Precision-cut human liver slices and 9 cell lines of different origin (breast, colon, oral cavity) were used as in vitro model systems. Our study showed that FLU with a reduced carbonyl group (FLUR) is the only FLU metabolite formed in the human liver. All human cancer cell lines were able to form FLUR. In addition, methylated FLUR was detected in breast cells MCF7 and intestinal SW480 cells. The accumulation of FLU and its reduction to FLUR markedly differed among cells. The extent of FLU reduction was in a good correlation with the detected expression level of carbonyl reductase 1. In most cases, FLU entered in a higher amount and was reduced to a lesser extent in proliferating (metastatic) cells than in differentiated (non-cancerous, non-metastatic) ones. These results support the promising potential of FLU in anti-cancer therapy.
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Affiliation(s)
- Lucie Raisová Stuchlíková
- Department of Biochemical Sciences, Faculty of Pharmacy, Charles University, Hradec Králové, Czech Republic
| | - Věra Králová
- Department of Biology, Faculty of Medicine, Charles University, Hradec Králové, Czech Republic
| | - Kateřina Lněničková
- Department of Biochemical Sciences, Faculty of Pharmacy, Charles University, Hradec Králové, Czech Republic
| | - Tomáš Zárybnický
- Department of Biochemical Sciences, Faculty of Pharmacy, Charles University, Hradec Králové, Czech Republic
| | - Petra Matoušková
- Department of Biochemical Sciences, Faculty of Pharmacy, Charles University, Hradec Králové, Czech Republic
| | - Veronika Hanušová
- Department of Biology, Faculty of Medicine, Charles University, Hradec Králové, Czech Republic
| | - Martin Ambrož
- Department of Biochemical Sciences, Faculty of Pharmacy, Charles University, Hradec Králové, Czech Republic
| | - Zdeněk Šubrt
- Department of Surgery, Faculty of Medicine, Charles University, Hradec Králové, Czech Republic
| | - Lenka Skálová
- Department of Biochemical Sciences, Faculty of Pharmacy, Charles University, Hradec Králové, Czech Republic
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Rosa BA, McNulty SN, Mitreva M, Jasmer DP. Direct experimental manipulation of intestinal cells in Ascaris suum, with minor influences on the global transcriptome. Int J Parasitol 2017; 47:271-279. [PMID: 28223178 DOI: 10.1016/j.ijpara.2016.12.005] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/02/2016] [Revised: 12/16/2016] [Accepted: 12/21/2016] [Indexed: 12/24/2022]
Abstract
Ascaris suum provides a powerful model for studying parasitic nematodes, including individual tissues such as the intestine, an established target for anthelmintic treatments. Here, we add a valuable experimental component to our existing functional, proteomic, transcriptomic and phylogenomic studies of the Ascaris suum intestine, by developing a method to manipulate intestinal cell functions via direct delivery of experimental treatments (in this case, double-stranded (ds)RNA) to the apical intestinal membrane. We developed an intestinal perfusion method for direct, controlled delivery of dsRNA/heterogeneous small interfering (hsi) RNA into the intestinal lumen for experimentation. RNA-Seq (22 samples) was used to assess influences of the method on global intestinal gene expression. Successful mRNA-specific knockdown in intestinal cells of adult A. suum was accomplished with this new experimental method. Global transcriptional profiling confirmed that targeted transcripts were knocked down more significantly than any others, with only 12 (0.07% of all genes) or 238 (1.3%) off-target gene transcripts consistently differentially regulated by dsRNA treatment or the perfusion experimental design, respectively (after 24h). The system supports controlled, effective delivery of treatments (dsRNA/hsiRNA) to the apical intestinal membrane with relatively minor off-target effects, and builds on our experimental model to dissect A. suum intestinal cell functions with broad relevance to parasitic nematodes.
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Affiliation(s)
- Bruce A Rosa
- The McDonnell Genome Institute, Washington University School of Medicine, St. Louis, MO 63108, USA
| | - Samantha N McNulty
- The McDonnell Genome Institute, Washington University School of Medicine, St. Louis, MO 63108, USA
| | - Makedonka Mitreva
- The McDonnell Genome Institute, Washington University School of Medicine, St. Louis, MO 63108, USA; Department of Medicine, Division of Infectious Diseases, Washington University School of Medicine, St. Louis, MO 63110, USA; Department of Genetics, Washington University School of Medicine, St. Louis, MO 63108, USA
| | - Douglas P Jasmer
- Department of Veterinary Microbiology and Pathology, Washington State University, Pullman, WA 99164, USA.
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17
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Loos JA, Dávila VA, Rodrígues CR, Petrigh R, Zoppi JA, Crocenzi FA, Cumino AC. Metformin exhibits preventive and therapeutic efficacy against experimental cystic echinococcosis. PLoS Negl Trop Dis 2017; 11:e0005370. [PMID: 28182659 PMCID: PMC5321462 DOI: 10.1371/journal.pntd.0005370] [Citation(s) in RCA: 15] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/27/2016] [Revised: 02/22/2017] [Accepted: 01/29/2017] [Indexed: 12/16/2022] Open
Abstract
Metformin (Met) is an anti-hyperglycemic and potential anti-cancer agent which may exert its anti-proliferative effects via the induction of energetic stress. In this study we investigated the in vitro and in vivo efficacy of Met against the larval stage of Echinococcus granulosus. Metformin showed significant dose- and time-dependent killing effects on in vitro cultured protoscoleces and metacestodes. Notably, the combination of Met together with the minimum effective concentration of ABZSO had a synergistic effect after days 3 and 12 on metacestodes and protoscoleces, respectively. Oral administration of Met (50 mg/kg/day) in E. granulosus-infected mice was highly effective in reducing the weight and number of parasite cysts, yet its combination with the lowest recommended dose of ABZ (5 mg/kg/day) was even more effective. Coincidentally, intracystic Met accumulation was higher in animals treated with both drugs compared to those administered Met alone. Furthermore, the safe plant-derived drug Met exhibited remarkable chemopreventive properties against secondary hydatidosis in mice. In conclusion, based on our experimental data, Met emerges as a promising anti-echinococcal drug as it has proven to efficiently inhibit the development and growth of the E. granulosus larval stage and its combination with ABZ may improve the current anti-parasitic therapy.
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Affiliation(s)
- Julia A. Loos
- Laboratorio de Zoonosis Parasitarias, Departamento de Biología, Facultad de Ciencias Exactas y Naturales, Universidad Nacional de Mar del Plata (UNMdP), Funes 3350, Nivel Cero, Mar del Plata, Argentina
- Consejo Nacional de Investigaciones Científicas y Técnicas (CONICET), Buenos Aires, Argentina
| | - Valeria A. Dávila
- Laboratorio de Zoonosis Parasitarias, Departamento de Biología, Facultad de Ciencias Exactas y Naturales, Universidad Nacional de Mar del Plata (UNMdP), Funes 3350, Nivel Cero, Mar del Plata, Argentina
- Consejo Nacional de Investigaciones Científicas y Técnicas (CONICET), Buenos Aires, Argentina
| | - Christian R. Rodrígues
- Consejo Nacional de Investigaciones Científicas y Técnicas (CONICET), Buenos Aires, Argentina
- Departamento de Química, Facultad de Ciencias Exactas y Naturales, Universidad Nacional de Mar del Plata (UNMdP), Funes 3350, Nivel 2, Mar del Plata, Argentina
| | - Romina Petrigh
- Laboratorio de Zoonosis Parasitarias, Departamento de Biología, Facultad de Ciencias Exactas y Naturales, Universidad Nacional de Mar del Plata (UNMdP), Funes 3350, Nivel Cero, Mar del Plata, Argentina
- Consejo Nacional de Investigaciones Científicas y Técnicas (CONICET), Buenos Aires, Argentina
| | - Jorge A. Zoppi
- Servicio de Patología, Hospital Privado de Comunidad (HPC), Córdoba 4545, Nivel 3, Mar del Plata, Argentina
| | - Fernando A. Crocenzi
- Consejo Nacional de Investigaciones Científicas y Técnicas (CONICET), Buenos Aires, Argentina
- Instituto de Fisiología Experimental (IFISE), Universidad Nacional de Rosario (UNR), Suipacha 570, Rosario, Argentina
| | - Andrea C. Cumino
- Laboratorio de Zoonosis Parasitarias, Departamento de Biología, Facultad de Ciencias Exactas y Naturales, Universidad Nacional de Mar del Plata (UNMdP), Funes 3350, Nivel Cero, Mar del Plata, Argentina
- Consejo Nacional de Investigaciones Científicas y Técnicas (CONICET), Buenos Aires, Argentina
- Departamento de Química, Facultad de Ciencias Exactas y Naturales, Universidad Nacional de Mar del Plata (UNMdP), Funes 3350, Nivel 2, Mar del Plata, Argentina
- * E-mail: (ACC)
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18
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Gao X, Tyagi R, Magrini V, Ly A, Jasmer DP, Mitreva M. Compartmentalization of functions and predicted miRNA regulation among contiguous regions of the nematode intestine. RNA Biol 2016; 14:1335-1352. [PMID: 27002534 DOI: 10.1080/15476286.2016.1166333] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/20/2022] Open
Abstract
The intestine of parasitic nematodes has proven an important target for therapies aimed at prevention and treatment of diseases caused by these pathogens in humans, animals and plants. We have developed a unique research model with the intestine of Ascaris suum, the large round worm of swine and humans, that will enhance biological research on this tissue. To expand utility of this model, we quantitatively compared expression of 15,382 coding RNAs and 277 noncoding, micro RNAs (miRNAs) among 3 contiguous regions of the adult A. suum intestine. Differentially expressed transcripts were identified among regions, with the largest number expressed at significantly higher levels in the anterior region, identifying this region as the most functionally unique compared to middle and posterior regions. We further identified 64 exon splice variants (from 47 genes) that are differentially expressed among these regions. A total of 2,063 intestinal mRNA transcripts were predicted to be targeted by intestinal miRNA, and negative correlation coefficients for miRNA:mRNA abundances predicted 22 likely influential miRNAs and 503 likely associated miRNA:mRNA pairs. A. suum intestinal miRNAs were identified that are conserved with intestinal miRNAs from C. elegans (10 mature sequences and 13 seed sequences conserved), and prospective intestinal miRNAs from the murine gastrointestinal nematode, Heligmosomoides polygyrus (5 mature and 11 seeds). Most of the conserved intestinal miRNAs were also high abundance miRNAs. The data provide the most comprehensive compilation of constitutively and differentially expressed genes along the length of the intestine for any nematode species. The information will guide prospective development of many hypotheses on nematode intestinal functions encoded by mRNAs, miRNAs and interactions between these RNA populations.
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Affiliation(s)
- Xin Gao
- a McDonnell Genome Institute, Washington University in St. Louis , St. Louis , MO , USA
| | - Rahul Tyagi
- a McDonnell Genome Institute, Washington University in St. Louis , St. Louis , MO , USA
| | - Vincent Magrini
- a McDonnell Genome Institute, Washington University in St. Louis , St. Louis , MO , USA
| | - Amy Ly
- a McDonnell Genome Institute, Washington University in St. Louis , St. Louis , MO , USA
| | - Douglas P Jasmer
- b Department of Veterinary Microbiology and Pathology , Washington State University , Pullman , WA , USA
| | - Makedonka Mitreva
- a McDonnell Genome Institute, Washington University in St. Louis , St. Louis , MO , USA.,c Department of Internal Medicine , Washington University School of Medicine , St. Louis , MO , USA
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Wang Q, Rosa BA, Jasmer DP, Mitreva M. Pan-Nematoda Transcriptomic Elucidation of Essential Intestinal Functions and Therapeutic Targets With Broad Potential. EBioMedicine 2015; 2:1079-89. [PMID: 26501106 PMCID: PMC4587998 DOI: 10.1016/j.ebiom.2015.07.030] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/06/2015] [Revised: 07/22/2015] [Accepted: 07/22/2015] [Indexed: 01/22/2023] Open
Abstract
The nematode intestine is continuous with the outside environment, making it easily accessible to anthelmintics for parasite control, but the development of new therapeutics is impeded by limited knowledge of nematode intestinal cell biology. We established the most comprehensive nematode intestinal functional database to date by generating transcriptional data from the dissected intestines of three parasitic nematodes spanning the phylum, and integrating the results with the whole proteomes of 10 nematodes (including 9 pathogens of humans or animals) and 3 host species and 2 outgroup species. We resolved 10,772 predicted nematode intestinal protein families (IntFams), and studied their presence and absence within the different lineages (births and deaths) among nematodes. Conserved intestinal cell functions representing ancestral functions of evolutionary importance were delineated, and molecular features useful for selective therapeutic targeting were identified. Molecular patterns conserved among IntFam proteins demonstrated large potential as therapeutic targets to inhibit intestinal cell functions with broad applications towards treatment and control of parasitic nematodes.
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Affiliation(s)
- Qi Wang
- McDonnell Genome Institute, Washington University School of Medicine, St. Louis, MO, USA
| | - Bruce A. Rosa
- McDonnell Genome Institute, Washington University School of Medicine, St. Louis, MO, USA
| | - Douglas P. Jasmer
- Department of Veterinary Microbiology and Pathology, Washington State University, Pullman, WA, USA
| | - Makedonka Mitreva
- McDonnell Genome Institute, Washington University School of Medicine, St. Louis, MO, USA
- Division of Infectious Disease, Department of Internal Medicine, Washington University School of Medicine, St. Louis, MO, USA
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20
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O'Neill M, Geary JF, Agnew DW, Mackenzie CD, Geary TG. In vitro flubendazole-induced damage to vital tissues in adult females of the filarial nematode Brugia malayi. INTERNATIONAL JOURNAL FOR PARASITOLOGY-DRUGS AND DRUG RESISTANCE 2015; 5:135-40. [PMID: 26288741 PMCID: PMC4534755 DOI: 10.1016/j.ijpddr.2015.06.002] [Citation(s) in RCA: 20] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 04/24/2015] [Revised: 06/17/2015] [Accepted: 06/19/2015] [Indexed: 11/26/2022]
Abstract
The use of a microfilaricidal drug for the control of onchocerciasis and lymphatic filariasis necessitates prolonged yearly dosing. Prospects for elimination or eradication of these diseases would be enhanced by availability of a macrofilaricidal drug. Flubendazole (FLBZ), a benzimidazole anthelmintic, is an appealing candidate macrofilaricide. FLBZ has demonstrated profound and potent macrofilaricidal effects in a number of experimental filarial rodent models and one human trial. Unfortunately, FLBZ was deemed unsatisfactory for use in mass drug administration (MDA) campaigns due to its markedly limited oral bioavailability. However, a new formulation that provided sufficient bioavailability following oral administration could render FLBZ an effective treatment for onchocerciasis and LF. This study characterized the effects of FLBZ and its reduced metabolite (FLBZ-R) on filarial nematodes in vitro to determine the exposure profile which results in demonstrable damage. Adult female Brugia malayi were exposed to varying concentrations of FLBZ or FLBZ-R (100 nM–10 μM) for up to five days, after which worms were fixed for histology. Morphological damage following exposure to FLBZ was observed prominently in the hypodermis and developing embryos at concentrations as low as 100 nM following 24 h exposure. The results indicate that damage to tissues required for reproduction and survival can be achieved at pharmacologically relevant concentrations. Detrimental effects observed in tissues required for development and survival. Damage occurs at concentrations ≥100 nM. Hypodermal and embryonic tissues exhibited the most severe damage. Oocytes and early morula are the most affected embryonic tissues.
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Affiliation(s)
- Maeghan O'Neill
- Institute of Parasitology and Centre for Host-Parasite Interactions, McGill University, Ste-Anne-de-Bellevue, QC H9X 3V9, Canada
| | - James F Geary
- Department of Pathobiology and Diagnostic Investigation, Michigan State University, East Lansing, MI 48824, USA
| | - Dalen W Agnew
- Department of Pathobiology and Diagnostic Investigation, Michigan State University, East Lansing, MI 48824, USA
| | - Charles D Mackenzie
- Department of Pathobiology and Diagnostic Investigation, Michigan State University, East Lansing, MI 48824, USA
| | - Timothy G Geary
- Institute of Parasitology and Centre for Host-Parasite Interactions, McGill University, Ste-Anne-de-Bellevue, QC H9X 3V9, Canada
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21
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Jasmer DP, Rosa BA, Mitreva M. Peptidases compartmentalized to the Ascaris suum intestinal lumen and apical intestinal membrane. PLoS Negl Trop Dis 2015; 9:e3375. [PMID: 25569475 PMCID: PMC4287503 DOI: 10.1371/journal.pntd.0003375] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/26/2014] [Accepted: 10/27/2014] [Indexed: 11/17/2022] Open
Abstract
The nematode intestine is a tissue of interest for developing new methods of therapy and control of parasitic nematodes. However, biological details of intestinal cell functions remain obscure, as do the proteins and molecular functions located on the apical intestinal membrane (AIM), and within the intestinal lumen (IL) of nematodes. Accordingly, methods were developed to gain a comprehensive identification of peptidases that function in the intestinal tract of adult female Ascaris suum. Peptidase activity was detected in multiple fractions of the A. suum intestine under pH conditions ranging from 5.0 to 8.0. Peptidase class inhibitors were used to characterize these activities. The fractions included whole lysates, membrane enriched fractions, and physiological- and 4 molar urea-perfusates of the intestinal lumen. Concanavalin A (ConA) was confirmed to bind to the AIM, and intestinal proteins affinity isolated on ConA-beads were compared to proteins from membrane and perfusate fractions by mass spectrometry. Twenty-nine predicted peptidases were identified including aspartic, cysteine, and serine peptidases, and an unexpectedly high number (16) of metallopeptidases. Many of these proteins co-localized to multiple fractions, providing independent support for localization to specific intestinal compartments, including the IL and AIM. This unique perfusion model produced the most comprehensive view of likely digestive peptidases that function in these intestinal compartments of A. suum, or any nematode. This model offers a means to directly determine functions of these proteins in the A. suum intestine and, more generally, deduce the wide array functions that exist in these cellular compartments of the nematode intestine. Past research has demonstrated that the nematode intestine has value for developing new methods of therapy and control of parasitic nematodes, as related to both vaccines and other anthelmintics. Yet, information related to basic intestinal cell biology is very limited. Research progress reported here moves towards the comprehensive identification of proteins (peptidases and others), and hence functions, that are sited on the apical intestinal membrane and within the intestinal lumen of adult female Ascaris suum. These advances provide an unprecedented research model to determine critical functions sited at these locations and to develop approaches to inhibit those functions. Comparative analysis among diverse parasitic species raises expectations that the results from A. suum can be applied to many parasitic nematodes for which similar research is technically impossible to perform.
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Affiliation(s)
- Douglas P Jasmer
- Department of Veterinary Microbiology and Pathology, Washington State University, Pullman, Washington, United States of America
| | - Bruce A Rosa
- The Genome Institute, Washington University School of Medicine, St. Louis, Missouri, United States of America
| | - Makedonka Mitreva
- The Genome Institute, Washington University School of Medicine, St. Louis, Missouri, United States of America; Department of Medicine and Department of Genetics, Washington University School of Medicine, St. Louis, Missouri, United States of America
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Antiproliferative effect of benzimidazole anthelmintics albendazole, ricobendazole, and flubendazole in intestinal cancer cell lines. Anticancer Drugs 2014; 24:911-9. [PMID: 23884106 DOI: 10.1097/cad.0b013e3283648c69] [Citation(s) in RCA: 45] [Impact Index Per Article: 4.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/27/2022]
Abstract
This study aimed to test the antiproliferative effect of three benzimidazole anthelmintics in intestinal cancer cells and to investigate whether these drugs, which inhibit tubulin polymerization, can potentiate the efficacy of the microtubule-stabilizing drug paclitaxel (PTX). Four intestinal cancer cell lines, SW480, SW620, HCT8, and Caco2, with different origins and growth characteristics were used. The antiproliferative effect of albendazole (ABZ), ricobendazole (RBZ), flubendazole (FLU), and their combinations with PTX was tested using three different end-point viability assays, cell cycle distribution analysis, and the x-CELLigence System for real-time cell analysis. ABZ and FLU inhibited cell proliferation significantly in a concentration-dependent and time-dependent manner through cell arrest in the G2/M phase. RBZ was not effective at any concentration tested. The cell lines differed in sensitivity to FLU and ABZ, with HCT8 being the most sensitive, showing IC₅₀ values for ABZ and FLU that reached 0.3 and 0.9 μmol/l, respectively. Combinations of PTX+ABZ and PTX+FLU decreased cell viability more effectively when compared with treatment with individual drugs alone. The anthelmintic benzimidazole drugs ABZ and FLU show a significant cytostatic effect and potentiate the efficacy of PTX in intestinal cancer cells.
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Taylor CM, Wang Q, Rosa BA, Huang SCC, Powell K, Schedl T, Pearce EJ, Abubucker S, Mitreva M. Discovery of anthelmintic drug targets and drugs using chokepoints in nematode metabolic pathways. PLoS Pathog 2013; 9:e1003505. [PMID: 23935495 PMCID: PMC3731235 DOI: 10.1371/journal.ppat.1003505] [Citation(s) in RCA: 59] [Impact Index Per Article: 5.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/28/2013] [Accepted: 06/03/2013] [Indexed: 12/19/2022] Open
Abstract
Parasitic roundworm infections plague more than 2 billion people (1/3 of humanity) and cause drastic losses in crops and livestock. New anthelmintic drugs are urgently needed as new drug resistance and environmental concerns arise. A “chokepoint reaction” is defined as a reaction that either consumes a unique substrate or produces a unique product. A chokepoint analysis provides a systematic method of identifying novel potential drug targets. Chokepoint enzymes were identified in the genomes of 10 nematode species, and the intersection and union of all chokepoint enzymes were found. By studying and experimentally testing available compounds known to target proteins orthologous to nematode chokepoint proteins in public databases, this study uncovers features of chokepoints that make them successful drug targets. Chemogenomic screening was performed on drug-like compounds from public drug databases to find existing compounds that target homologs of nematode chokepoints. The compounds were prioritized based on chemical properties frequently found in successful drugs and were experimentally tested using Caenorhabditis elegans. Several drugs that are already known anthelmintic drugs and novel candidate targets were identified. Seven of the compounds were tested in Caenorhabditis elegans and three yielded a detrimental phenotype. One of these three drug-like compounds, Perhexiline, also yielded a deleterious effect in Haemonchus contortus and Onchocerca lienalis, two nematodes with divergent forms of parasitism. Perhexiline, known to affect the fatty acid oxidation pathway in mammals, caused a reduction in oxygen consumption rates in C. elegans and genome-wide gene expression profiles provided an additional confirmation of its mode of action. Computational modeling of Perhexiline and its target provided structural insights regarding its binding mode and specificity. Our lists of prioritized drug targets and drug-like compounds have potential to expedite the discovery of new anthelmintic drugs with broad-spectrum efficacy. The World Health Organization estimates that 2.9 million people are infected with parasitic roundworms, causing high-morbidity and mortality rates, developmental delays in children, and low productivity of affected individuals. The agricultural industry experiences drastic losses in crop and livestock due to parasitic worm infections. Therefore, there is an urgent need to identify new targets and drugs to fight parasitic nematode infection. This study identified metabolic chokepoint compounds that were either produced or consumed by a single reaction and elucidated the chokepoint enzyme that drives the reaction. If the enzyme that catalyzes that reaction is blocked, a toxic build-up of a compound or lack of compound necessary for subsequent reaction will occur, potentially causing adverse effects to the parasite organism. Compounds that target some of the chokepoint enzymes were tested in C. elegans and several compounds showed efficacy. One drug-like compound, Perhexiline, showed efficacy in two different parasitic worms and yielded expected physiological effects, indicating that this drug-like compound may have efficacy on a pan-phylum level through the predicted mode of action. The methodology to find and prioritize metabolic chokepoint targets and prioritize compounds could be applied to other parasites.
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Affiliation(s)
- Christina M. Taylor
- The Genome Institute, Washington University School of Medicine, St. Louis, Missouri, United States of America
| | - Qi Wang
- The Genome Institute, Washington University School of Medicine, St. Louis, Missouri, United States of America
| | - Bruce A. Rosa
- The Genome Institute, Washington University School of Medicine, St. Louis, Missouri, United States of America
| | - Stanley Ching-Cheng Huang
- Department of Pathology and Immunology, Washington University School of Medicine, St. Louis, Missouri, United States of America
| | - Kerrie Powell
- SCYNEXIS, Inc, Research Triangle Park, North Carolina, United States of America
| | - Tim Schedl
- Department of Genetics, Washington University School of Medicine, St. Louis, Missouri, United States of America
| | - Edward J. Pearce
- Department of Pathology and Immunology, Washington University School of Medicine, St. Louis, Missouri, United States of America
| | - Sahar Abubucker
- The Genome Institute, Washington University School of Medicine, St. Louis, Missouri, United States of America
| | - Makedonka Mitreva
- The Genome Institute, Washington University School of Medicine, St. Louis, Missouri, United States of America
- Department of Genetics, Washington University School of Medicine, St. Louis, Missouri, United States of America
- Division of Infectious Diseases, Department of Internal Medicine, Genetics, Washington University School of Medicine, St. Louis, Missouri, United States of America
- * E-mail:
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Gene expression analysis distinguishes tissue-specific and gender-related functions among adult Ascaris suum tissues. Mol Genet Genomics 2013; 288:243-60. [PMID: 23572074 DOI: 10.1007/s00438-013-0743-y] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/31/2012] [Accepted: 03/19/2013] [Indexed: 12/15/2022]
Abstract
Over a billion people are infected by Ascaris spp. intestinal parasites. To clarify functional differences among tissues of adult A. suum, we compared gene expression by various tissues of these worms by expression microarray methods. The A. suum genome was sequenced and assembled to allow generation of microarray elements. Expression of over 40,000 60-mer elements was investigated in a variety of tissues from both male and female adult worms. Nearly 50 percent of the elements for which signal was detected exhibited differential expression among different tissues. The unique profile of transcripts identified for each tissue clarified functional distinctions among tissues, such as chitin binding in the ovary and peptidase activity in the intestines. Interestingly, hundreds of gender-specific elements were characterized in multiple non-reproductive tissues of female or male worms, with most prominence of gender differences in intestinal tissue. A. suum genes from the same family were frequently expressed differently among tissues. Transcript abundance for genes specific to A. suum, by comparison to Caenorhabditis elegans, varied to a greater extent among tissues than for genes conserved between A. suum and C. elegans. Analysis using C. elegans protein interaction data identified functional modules conserved between these two nematodes, resulting in identification of functional predictions of essential subnetworks of protein interactions and how these networks may vary among nematode tissues. A notable finding was very high module similarity between adult reproductive tissues and intestine. Our results provide the most comprehensive assessment of gene expression among tissues of a parasitic nematode to date.
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Using existing drugs as leads for broad spectrum anthelmintics targeting protein kinases. PLoS Pathog 2013; 9:e1003149. [PMID: 23459584 PMCID: PMC3573124 DOI: 10.1371/journal.ppat.1003149] [Citation(s) in RCA: 34] [Impact Index Per Article: 3.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/02/2012] [Accepted: 11/29/2012] [Indexed: 01/22/2023] Open
Abstract
As one of the largest protein families, protein kinases (PKs) regulate nearly all processes within the cell and are considered important drug targets. Much research has been conducted on inhibitors for PKs, leading to a wealth of compounds that target PKs that have potential to be lead anthelmintic drugs. Identifying compounds that have already been developed to treat neglected tropical diseases is an attractive way to obtain lead compounds inexpensively that can be developed into much needed drugs, especially for use in developing countries. In this study, PKs from nematodes, hosts, and DrugBank were identified and classified into kinase families and subfamilies. Nematode proteins were placed into orthologous groups that span the phylum Nematoda. A minimal kinome for the phylum Nematoda was identified, and properties of the minimal kinome were explored. Orthologous groups from the minimal kinome were prioritized for experimental testing based on RNAi phenotype of the Caenorhabditis elegans ortholog, transcript expression over the life-cycle and anatomic expression patterns. Compounds linked to targets in DrugBank belonging to the same kinase families and subfamilies in the minimal nematode kinome were extracted. Thirty-five compounds were tested in the non-parasitic C. elegans and active compounds progressed to testing against nematode species with different modes of parasitism, the blood-feeding Haemonchus contortus and the filarial Brugia malayi. Eighteen compounds showed efficacy in C. elegans, and six compounds also showed efficacy in at least one of the parasitic species. Hypotheses regarding the pathway the compounds may target and their molecular mechanism for activity are discussed. Parasitic nematode infection is a large global health and economic problem, infecting around 2 billion people and costing $100 billion in crops and livestock. People in developing countries often live on one dollar per day, so treatments cannot be expensive, therefore using pre-existing drugs as lead compounds provides an economical way to begin to develop affordable treatments. Protein kinases were chosen as the focus of this work due to the large number of pre-existing drugs that target them and their important role in regulating almost all activities in the cell. Herein we describe a set of protein kinases conserved in diverse nematode species and experimental screening results of pre-existing drugs that target these kinases. The compounds that show in vitro efficacy in both C. elegans and parasitic nematodes, H. contortus or B. malayi have potential to be optimized further. These compounds have potential to provide accessible treatment to people in developing countries, as well as improving the health of livestock and boosting food production globally.
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Britton C, Samarasinghe B, Knox DP. Ups and downs of RNA interference in parasitic nematodes. Exp Parasitol 2012; 132:56-61. [DOI: 10.1016/j.exppara.2011.08.002] [Citation(s) in RCA: 23] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/10/2011] [Revised: 07/27/2011] [Accepted: 08/03/2011] [Indexed: 01/06/2023]
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Synthesis and biological evaluation of some novel 2-phenyl benzimidazole-1-acetamide derivatives as potential anthelmintic agents. ACTA PHARMACEUTICA 2011; 61:353-61. [PMID: 21945914 DOI: 10.2478/v10007-011-0029-z] [Citation(s) in RCA: 25] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/20/2022]
Abstract
The present study describes synthesis of a series of 2-phenyl benzimidazole-1-acetamide derivatives and their evaluation for anthelmintic activity using Indian adult earthworms, Pheretima posthuma. The structure of the title compounds was elucidated by elemental analysis and spectral data. The compounds 4-({[2-(4-nitrophenyl)-1H-benzimidazol-1-yl]acetyl}amino) benzoic acid (3a), N-ethyl-2-[2-(4-nitrophenyl)-1H-benzimidazol-1-yl] acetamide (3c), N-benzyl-2-[2-(4-nitrophenyl)-1H-benzimidazol-1-yl] acetamide (3d), N-(4-hydroxyphenyl)-2-[2-(4-nitrophenyl)-1H-benzimidazol-1-yl] acetamide (3f), 2-[2-(4-nitrophenyl)-1H-benzimidazol-1-yl]-N-phenyl acetamide (3h), 2-[2-(4-chlorophenyl)-1H-benzimidazol-1-yl]-N'-phenylacetohydrazide (3k), 2-[2-(4-chlorophenyl)-1H-benzimidazol-1-yl]-N-(4-nitrophenyl) acetamide (3n) and 2-[2-(4-chlorophenyl)-1H-benzimidazol-1-yl]-N-phenyl acetamide (3q) were found better to paralyze worms whereas N-ethyl-2-[2-(4-nitrophenyl)-1H-benzimidazol-1-yl] acetamide (3c), N-(4-nitrophenyl)-2-[2-(4-nitrophenyl)-1H-benzimidazol-1-yl] acetamide (3e), 4-({[2-(4-chlorophenyl)-1H-benzimidazol-1-yl] acetyl}amino) benzoic acid (3j), 2-[2-(4-chlorophenyl)-1H-benzimidazol-1-yl]-N-ethyl acetamide (31) and 2-[2-(4-chlorophenyl)-1H-benzimidazol-1-yl]-N-phenyl acetamide (3q) were better to cause death of worms compared to the anthelmintic drug albendazole.
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Characteristics of DNase activities in excretory/secretory products of infective larvae ofHaemonchus contortus. J Helminthol 2011; 86:363-7. [DOI: 10.1017/s0022149x11000496] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/07/2022]
Abstract
AbstractWhile multiple DNase activities occur in the excretory/secretory products (ESPs) of the adultHaemonchus contortus, the DNase activities in ESPs of the infective larvae (L3) have not been studied. Thus, the DNase activities in ESPs ofH. contortusL3 were investigated and compared to those of adults for developmental stage-specific analysis. The DNase activities had relative molecular masses (Mrs) of 34 and 36 kDa upon zymographic analysis at pH 5.0 and 7.0 when the larvae were incubated for over 48 h. The 34 and 36 kDa DNases of L3 ESPs were also detected in adult ESPs with similar characteristics. However, the 37 and 38.5 kDa DNases of the adult ESPs were not detected in the L3 ESPs. Since the 37 and 38.5 kDa DNase activities were mainly detected in adult ESPs, these activities appear to be specific to the adult stage whereas the other ESP DNase activities appear to be expressed during multiple stages of the parasite's life cycle. While the difference in DNase activities of L3 and adults remains obscure, the role of DNase in larval development should be further clarified and the identification of stage-specific developmental markers will lead to the discovery of specific factors that stimulate larval development.
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Fractionation of DNases Specific toHaemonchus contortusIntestine by Phenyl Sepharose Column. Lab Anim Res 2010. [DOI: 10.5625/lar.2010.26.2.139] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022] Open
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Yin Y, Martin J, Abubucker S, Wang Z, Wyrwicz L, Rychlewski L, McCarter JP, Wilson RK, Mitreva M. Molecular determinants archetypical to the phylum Nematoda. BMC Genomics 2009; 10:114. [PMID: 19296854 PMCID: PMC2666764 DOI: 10.1186/1471-2164-10-114] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/15/2008] [Accepted: 03/18/2009] [Indexed: 11/10/2022] Open
Abstract
Background Nematoda diverged from other animals between 600–1,200 million years ago and has become one of the most diverse animal phyla on earth. Most nematodes are free-living animals, but many are parasites of plants and animals including humans, posing major ecological and economical challenges around the world. Results We investigated phylum-specific molecular characteristics in Nematoda by exploring over 214,000 polypeptides from 32 nematode species including 27 parasites. Over 50,000 nematode protein families were identified based on primary sequence, including ~10% with members from at least three different species. Nearly 1,600 of the multi-species families did not share homology to Pfam domains, including a total of 758 restricted to Nematoda. Majority of the 462 families that were conserved among both free-living and parasitic species contained members from multiple nematode clades, yet ~90% of the 296 parasite-specific families originated only from a single clade. Features of these protein families were revealed through extrapolation of essential functions from observed RNAi phenotypes in C. elegans, bioinformatics-based functional annotations, identification of distant homology based on protein folds, and prediction of expression at accessible nematode surfaces. In addition, we identified a group of nematode-restricted sequence features in energy-generating electron transfer complexes as potential targets for new chemicals with minimal or no toxicity to the host. Conclusion This study identified and characterized the molecular determinants that help in defining the phylum Nematoda, and therefore improved our understanding of nematode protein evolution and provided novel insights for the development of next generation parasite control strategies.
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Affiliation(s)
- Yong Yin
- The Genome Center, Department of Genetics, Washington University School of Medicine, St Louis, Missouri, USA.
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Advances in the sequencing of the genome of the adenophorean nematode Trichinella spiralis. Parasitology 2008; 135:869-80. [PMID: 18598573 DOI: 10.1017/s0031182008004472] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/05/2022]
Abstract
The adenophorean nematodes are evolutionarily distant from other species in the phylum Nematoda. Interspecific comparisons of predicted proteins have supported such an ancient divergence. Accordingly, Trichinella spiralis represents a basal nematode representative for genome sequencing focused on gaining a deeper insight into the evolutionary biology of nematodes. In addition, molecular characteristics that are conserved across the phylum could be of great value for control strategies with broad application. In this review, we describe and summarize progress that has been made on the sequencing and analysis of the T. spiralis genome. The genome sequence was used in preliminary analyses for the investigation of specific questions relating to the biology of T. spiralis and, more generally, to parasitic nematodes. For instance, we evaluated an unusually large DNase II-like protein family, predicted proteins of prospective interest in the parasite-host muscle cell interaction, anthelmintic targets and prospective intestinal genes, the encoded proteins (potentially) linked to immunological control against other nematodes. The results are discussed in relation to characteristics that are broadly conserved among evolutionary distant nematodes. The results lead to expectations that this genome sequence will contribute to advances in research on T. spiralis and other parasitic nematodes.
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Yin Y, Martin J, Abubucker S, Scott AL, McCarter JP, Wilson RK, Jasmer DP, Mitreva M. Intestinal transcriptomes of nematodes: comparison of the parasites Ascaris suum and Haemonchus contortus with the free-living Caenorhabditis elegans. PLoS Negl Trop Dis 2008; 2:e269. [PMID: 18682827 PMCID: PMC2483350 DOI: 10.1371/journal.pntd.0000269] [Citation(s) in RCA: 36] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/09/2008] [Accepted: 07/02/2008] [Indexed: 11/18/2022] Open
Abstract
Background The nematode intestine is a major organ responsible for nutrient digestion and absorption; it is also involved in many other processes, such as reproduction, innate immunity, stress responses, and aging. The importance of the intestine as a target for the control of parasitic nematodes has been demonstrated. However, the lack of detailed knowledge on the molecular and cellular functions of the intestine and the level of its conservation across nematodes has impeded breakthroughs in this application. Methods and Findings As part of an extensive effort to investigate various transcribed genomes from Ascaris suum and Haemonchus contortus, we generated a large collection of intestinal sequences from parasitic nematodes by identifying 3,121 A. suum and 1,755 H. contortus genes expressed in the adult intestine through the generation of expressed sequence tags. Cross-species comparisons to the intestine of the free-living C. elegans revealed substantial diversification in the adult intestinal transcriptomes among these species, suggesting lineage- or species-specific adaptations during nematode evolution. In contrast, significant conservation of the intestinal gene repertories was also evident, despite the evolutionary distance of ∼350 million years separating them. A group of 241 intestinal protein families (IntFam-241), each containing members from all three species, was identified based on sequence similarities. These conserved proteins accounted for ∼20% of the sampled intestinal transcriptomes from the three nematodes and are proposed to represent conserved core functions in the nematode intestine. Functional characterizations of the IntFam-241 suggested important roles in molecular functions such as protein kinases and proteases, and biological pathways of carbohydrate metabolism, energy metabolism, and translation. Conservation in the core protein families was further explored by extrapolating observable RNA interference phenotypes in C. elegans to their parasitic counterparts. Conclusions Our study has provided novel insights into the nematode intestine and lays foundations for further comparative studies on biology, parasitism, and evolution within the phylum Nematoda. Biological properties of the nematode intestine warrant in-depth investigation, the results of which can be utilized in the control of parasitic nematodes that infect humans, livestock, and plants. Both the importance of intestinal antigens from Haemonchus contortus in immunity and the damage to H. contortus intestine by anthelmintic fenbendazole have highlighted the versatility of the intestine as an emerging target. However, biological information regarding fundamental intestinal cell functions and mechanisms is currently limited. Conserved intestinal genes across nematode pathogens could offer molecular targets for broad parasite control. Furthermore, qualitative and quantitative comparisons on intestinal gene expression among species and lineages can identify basic adaptations relative to a critical selective force, the nutrient acquisition. This study begins to identify intestinal cell characteristics that are conserved across representatives of two clades of nematodes (V and III) and further clarifies diversities that likely reflect species- or lineage-specific adaptations. Results consistent with functional data on digestive enzymes from H. contortus and RNAi in Caenorhabditis elegans, as examples, support the potential for the comparative genomics approach to produce practical applications. This study provides a platform on which extensive investigation of intestinal genes and a more comprehensive understanding of the Nematoda can be gained.
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Affiliation(s)
- Yong Yin
- Genome Sequencing Center, Department of Genetics, Washington University School of Medicine, St. Louis, Missouri, United States of America.
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Smith WD. Attempts to detect synergy between vaccination and anthelmintic against a drug resistant isolate of Haemonchus contortus. Vet Parasitol 2007; 148:356-9. [PMID: 17643823 DOI: 10.1016/j.vetpar.2007.06.027] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/16/2007] [Revised: 06/20/2007] [Accepted: 06/21/2007] [Indexed: 11/15/2022]
Abstract
An experiment was conducted to determine whether any synergistic activity could be detected between an experimental vaccine and anthelmintic treatment against a drug resistant strain of Haemonchus contortus, i.e. would the combined effect of both interventions be greater than the sum of either alone. Two groups of 14 worm-free sheep were immunised twice, either with Haemonchus galactose containing glycoprotein complex (H-gal-GP) in QuilA as adjuvant or with adjuvant alone. All were challenged with 5000 Haemonchus L3 from the White River isolate which were resistant to ivermectin and fenbendazole. By 26 days post-challenge the H-gal-GP vaccinated sheep had shed 89% fewer nematode eggs than the adjuvant only controls, indicating that this antigen did indeed protect against the anthelmintic resistant isolate. Twenty six days after challenge seven vaccinates and seven control sheep were drenched with ivermectin, but over the next 11 days the mean egg count of either group did not differ significantly from those of the corresponding untreated groups of sheep. On day 37 the drenched sheep were treated with fenbendazole. This time the egg counts of both treated groups fell significantly compared to those of the corresponding untreated groups, but again there was no suggestion that the drug was more effective in the vaccinated sheep. It was concluded that there was no evidence for synergy between a gut membrane protein vaccine and ivermectin or fenbendazole against an anthelmintic resistant isolate of H. contortus.
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Affiliation(s)
- W D Smith
- Moredun Research Institute, Pentlands Science Park, Bush Loan, Penicuik, Scotland EH26 0PZ, UK.
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Bhattacharya S, Chaudhuri P. Metal-Ion-Mediated Tuning of Duplex DNA Binding by Bis(2-(2-pyridyl)-1H-benzimidazole). Chem Asian J 2007; 2:648-55. [PMID: 17455175 DOI: 10.1002/asia.200700014] [Citation(s) in RCA: 14] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022]
Abstract
Studies of double-stranded-DNA binding have been performed with three isomeric bis(2-(n-pyridyl)-1H-benzimidazole)s (n=2, 3, 4). Like the well-known Hoechst 33258, which is a bisbenzimidazole compound, these three isomers bind to the minor groove of duplex DNA. DNA binding by the three isomers was investigated in the presence of the divalent metal ions Mg(2+), Co(2+), Ni(2+), Cu(2+), and Zn(2+). Ligand-DNA interactions were probed with fluorescence and circular dichroism spectroscopy. These studies revealed that the binding of the 2-pyridyl derivative to DNA is dramatically reduced in the presence of Co(2+), Ni(2+), and Cu(2+) ions and is abolished completely at a ligand/metal-cation ratio of 1:1. Control experiments done with the isomeric 3- and 4-pyridyl derivatives showed that their binding to DNA is unaffected by the aforementioned transition-metal ions. The ability of 2-(2-pyridyl)benzimidazole to chelate metal ions and the conformational changes of the ligand associated with ion chelation probably led to such unusual binding results for the ortho isomer. The addition of ethylenediaminetetraacetic acid (EDTA) reversed the effects completely.
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Affiliation(s)
- Santanu Bhattacharya
- Department of Organic Chemistry, Indian Institute of Science, Bangalore 560012, India.
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Abstract
Genomic filtering is a rapid approach to identifying and prioritizing molecular targets for drug discovery. For infectious disease applications, comparative genomics filters allow the selection of pathogen-specific gene products, whereas functional genomics filters, such as RNA interference (RNAi), allow the selection of gene products essential for pathogen survival. The approach is especially applicable to antiparasitic drug discovery where the phylogenetic distance between parasite and host make the likelihood of drug cross-toxicity due to conservation of molecular targets greater than for more distantly related pathogens such as prokaryotes. This article discusses some of the inherent challenges of applying genomics to the early steps of drug discovery and describes one successful comparative and functional genomics filtering strategy that has been implemented to prioritize molecular targets and identify chemical leads for nematode control.
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Affiliation(s)
- James P McCarter
- Divergence Inc., 893 North Warson Road, St Louis, MO 63141, USA.
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Kwak D, Jasmer DP. Intestinal DNases of 36 and 38.5kDa from the parasitic nematode Haemonchus contortus have non-classic DNase characteristics and produce DNA fragments with 3′-hydroxyls. Exp Parasitol 2004; 108:142-53. [PMID: 15582511 DOI: 10.1016/j.exppara.2004.07.016] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/08/2004] [Revised: 04/08/2004] [Accepted: 07/27/2004] [Indexed: 11/22/2022]
Abstract
Treatment with the anthelmintic fenbendazole induces fragmentation of genomic DNA in intestinal cells of Haemonchus contortus. This effect is characterized by DNA fragments with 3'-hydroxyls (OH). Investigation into DNases responsible identified intestinal DNase activities that produce DNA fragments with 3'-OH. However, this interpretation was complicated by a mixture of activities in the intestinal fractions evaluated. In addition, intestinal activities displayed non-classic characteristics. Here it is shown that heparin sulfate (HS) fractionation enriched for intestinal DNases that produce 3'-OH. The 2.0M NaCl fraction of HS contained DNase activity that produced 3'-OH with minimal contamination by activity that produced 3'-phosphates (P). 3'-OH were produced under acidic (pH 5.0) or neutral (pH 7.0) conditions by DNases in this fraction. These DNases were sensitive to EDTA under each condition. Furthermore, EDTA-sensitive DNase activity in this fraction digested H. contortus intestinal cell nuclear DNA in histological sections, producing 3'-OH under acidic and neutral conditions. DNases at 36 and 38.5kDa in this fraction each produced 3'-OH at pH 5.0 when gel eluted, and each activity was sensitive to EDTA. Hence, the 36 and 38.5kDa DNases in the 2.0M NaCl HS intestinal fraction have characteristics expected for candidate DNases that mediate DF in H. contortus intestinal cell nuclei induced by fenbendazole. DNase activity that produces 3'-OH under acidic condition with sensitivity to EDTA is unconventional for classic acidic or neutral DNases and is a unique finding for nematodes. Excretory/secretory products from the worm and whole worm lysates were also explored as sources to fractionate intestinal DNases identified. HS fractionation of those worm samples did not clearly resolve the intestinal DNases of interest, although DNases with distinct characteristics were identified in each source.
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Affiliation(s)
- Dongmi Kwak
- Department of Veterinary Microbiology and Pathology, Washington State University, Pullman, WA 99164-7040, USA
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Jasmer DP, Mitreva MD, McCarter JP. mRNA sequences for Haemonchus contortus intestinal cathepsin B-like cysteine proteases display an extreme in abundance and diversity compared with other adult mammalian parasitic nematodes. Mol Biochem Parasitol 2004; 137:297-305. [PMID: 15383300 DOI: 10.1016/j.molbiopara.2004.06.010] [Citation(s) in RCA: 42] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/10/2003] [Revised: 06/21/2004] [Accepted: 06/25/2004] [Indexed: 10/26/2022]
Abstract
Cathepsin B-like cysteine protease (cbl) genes produce the most abundant mRNAs ( approximately 16%) detected in the adult female intestine of the parasitic nematode Haemonchus contortus. CBL enzymes appear to digest host proteins and are vaccine candidates for immune control of H. contortus and potentially other parasitic nematodes. Hence, it is important to quantify the extent of diversity of H. contortuscbl genes. Here, expressed sequence tags (ESTs) were used to assess both the size and diversity of the H. contortuscbl gene family. Contig analysis of 686 cbl ESTs from a USA isolate resolved 123 clusters. ESTs were grouped into discrete sets and analyzed using an additive model. Discovery of new cbl clusters increased with each set and reached a terminal rate of about 1 per 10 ESTs. The extreme diversity was unique to cbls relative to other genes investigated and was ascribed to specific cbl clades. Sixty percent of cbl clusters from a UK isolate were shared with those identified in the USA isolate, suggesting conservation of cbl gene repertoires across regions, although minor to moderate geographic variation cannot be excluded. Sequence comparisons also suggested high potential for antigenic diversity among CBL proteins, which is relevant to vaccine strategies. Compared to other parasitic nematodes of mammals, the extreme abundance and diversity of intestinal cbl transcripts appear to be relative specializations for H. contortus. Therefore, adaptations related to nutrient acquisition may vary markedly among these parasitic nematodes.
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Affiliation(s)
- Douglas P Jasmer
- Department of Veterinary Microbiology and Pathology, Washington State University, Pullman, WA 9916407040, USA
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Reed SM, Bayly WM, Sellon DC. Mechanisms of Infectious Disease. EQUINE INTERNAL MEDICINE 2004. [PMCID: PMC7278211 DOI: 10.1016/b0-72-169777-1/50004-4] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Indexed: 10/27/2022]
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39
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Shompole S, Jasmer DP. Haemonchus contortus UNC-18 binds to Caenorhabditis elegans neuronal syntaxin. Mol Biochem Parasitol 2003; 130:55-9. [PMID: 14550897 DOI: 10.1016/s0166-6851(03)00136-1] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.0] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/01/2022]
Affiliation(s)
- Sankale Shompole
- Department of Veterinary Microbiology and Pathology, Washington State University, Pullman, WA 99164-7040, USA
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Shompole S, Yao C, Cheng X, Knox D, Johnson S, Jasmer DP. Distinct characteristics of two intestinal protein compartments discriminated by using fenbendazole and a benzimidazole resistant isolate of Haemonchus contortus. Exp Parasitol 2002; 101:200-9. [PMID: 12594960 DOI: 10.1016/s0014-4894(02)00135-2] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Abstract
The intestine of Haemonchus contortus is hypersensitive to the effects of the anthelmintic fenbendazole (FBZ). The effects are postulated to stem from disruption of microtubules and interference with apical secretory vesicle transport, followed by release of digestive enzymes into the intestinal cell cytoplasm. Here, FBZ caused marker proteins for both apical (pepsinogen-like protease, PEP-1) and basal (cystatin-like protein) protein compartments to became homogeneously distributed in the cytoplasm of H. contortus intestinal cells. The observations with PEP-1 support the hypothesis that release of hydrolytic enzymes into the intestinal cell cytoplasm contributes to the mechanism of benzimidazole efficacy. A benzimidazole resistant isolate of H. contortus expressed type 1 and 2 intestinal beta-tubulin transcripts that would encode predominantly tyr200 and phe200 variants, respectively. This isolate was resistant to the known intestinal cell alterations induced by FBZ treatment in the susceptible isolate, including inhibition of apical vesicle transport. These results implicate type 1 beta-tubulin in mediating apical vesicle transport in intestinal cells and suggest that the tyr200 variant is a determinant of FBZ resistance in intestinal cells. In contrast, the basal protein compartment demonstrated sensitivity to FBZ treatment in these otherwise "resistant" worms. Hence, distinct FBZ-sensitive components appear to be involved in distributing intestinal proteins into the described apical and basal compartments of normal worms.
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Affiliation(s)
- Sankale Shompole
- Department of Veterinary Microbiology and Pathology, Washington State University, Pullman, WA 99164-7040, USA
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41
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Jasmer DP, Roth J, Myler PJ. Cathepsin B-like cysteine proteases and Caenorhabditis elegans homologues dominate gene products expressed in adult Haemonchus contortus intestine. Mol Biochem Parasitol 2001; 116:159-69. [PMID: 11522349 DOI: 10.1016/s0166-6851(01)00312-7] [Citation(s) in RCA: 36] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/18/2022]
Abstract
Proteins expressed by nematode intestinal cells are potential targets for parasite control by immune or chemical based strategies. To expand our knowledge on nematode intestinal proteins, expressed sequence tags were generated for 131 cDNA clones from the intestine of adult female Haemonchus contortus. An estimated 55 distinct protein genes or gene families were identified. Predicted proteins represented diverse functions. Several predicted polypeptides were related to H. contortus proteins implicated in inducing protective immunity against challenge infections of this parasite. The dominant intestinal transcripts were represented by cathepsin B-like cysteine protease genes (cbl) (17% of protein coding expressed sequence tags (ESTs) analyzed). An estimated 11 previously undescribed cbl genes were identified, doubling the recognized members of this gene family. Multiple C-type lectin sequences were identified. Other notable sequences included a predicted Y-box binding protein, serine/threonine kinases and a cyclin E-like sequence. Predicted protein homologues were found in Caenorhabditis elegans for all but one H. contortus sequence (99%), while fewer homologues from other parasitic nematodes were found. Many of the proteases, lipase and C-type lectin homologues in C. elegans had apparent signal peptides, suggesting that they are secreted. Several gene products had no obvious similarity outside the phylum Nematoda. The ESTs identified intestinal genes with potential application to immune control, understanding of basic intestinal regulatory processes and refinement of nematode genomic resources.
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Affiliation(s)
- D P Jasmer
- Department of Veterinary Microbiology and Pathology, Washington State University, Pullman, WA 99164-7040, USA.
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Satou T, Koga M, Koike K, Tada I, Nikaido T. Nematocidal activities of thiabendazole and ivermectin against the larvae of Strongyloides ratti and S. venezuelensis. Vet Parasitol 2001; 99:311-22. [PMID: 11511418 DOI: 10.1016/s0304-4017(01)00472-1] [Citation(s) in RCA: 17] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/18/2022]
Abstract
With the aim of developing therapeutic agents for strongyloidosis, the disease caused by infection with Strongyloides stercoralis, we established a novel assay technique using S. ratti and S. venezuelensis as models for S. stercoralis. The newly developed assay technique was found to more accurately represent treatment-induced larval paralysis than existing assays. Our method uses paper disks impregnated with the test solution, which even allows materials that are sparingly soluble in water to be tested. An inverted microscope was used to observe the larval states, and these states were recorded using a digital camera. We observed the activities of ivermectin and thiabendazole against larvae and calculated larval motility and velocity. These two factors were then combined to determine the overall viability of larvae at selected concentrations. The activities of the anthelmintics were compared by calculating the concentrations at which 50% viability was demonstrated, or in other words, the concentration at which paralysis was caused in 50% of the individuals (50% paralysis concentration; PC(50)). Evaluations after 24h of exposure yielded the following reproducible PC(50) values for ivermectin and thiabendazole, respectively: S. ratti, 2.4 and 140 microM; and S. venezuelensis, 2.3 and 190 microM. After treatment with ivermectin, there was a tendency for larval motility to be greater than that of the controls at low concentrations, a result that might be associated with its mechanism of action.
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Affiliation(s)
- T Satou
- Department of Pharmacognosy, School of Pharmaceutical Sciences, Toho University, 2-2-1 Miyama, Funabashi, Chiba 2748510, Japan
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Abstract
The most commonly used modern anthelmintics include the benzimidazoles, the nicotinic agonists. praziquantel, triclabendazole and the macrocyclic lactones. These drugs interfere with target sites that are either unique to the parasite or differ in their structural features from those of the homologous counterpart present in the vertebrate host. The benzimidazoles exert their effect by binding selectively and with high affinity to the beta-subunit of helminth microtubule protein. The target site of the nicotinic agonists (e.g. levamisole, tetrahydropyrimidines) is a pharmacologically distinct nicotinic acetylcholine receptor channel in nematodes. The macrocyclic lactones (e.g. ivermectin, moxidectin) act as agonists of a family of invertebrate-specific inhibitory chloride channels that are activated by glutamic acid. The primary mode of action of other important anthelmintics (e.g. praziquantel, triclabendazole) is unknown. Anthelmintic resistance is wide-spread and a serious threat to effective control of helminth infections, especially in the veterinary area. The biochemical and genetic mechanisms underlying anthelmintic resistance are not well understood, but appear to be complex and vary among different helminth species and even isolates. The major mechanisms helminths use to acquire drug resistance appear to be through receptor loss or decrease of the target site affinity for the drug. Knowledge on the mechanisms of drug action and resistance may be exploitable for the development of new drugs and may provide information on ways to overcome parasite resistance, respectively.
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Affiliation(s)
- P Köhler
- Institute of Parasitology, University of Zürich, Switzerland.
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Shompole S, Jasmer DP. Cathepsin B-like cysteine proteases confer intestinal cysteine protease activity in Haemonchus contortus. J Biol Chem 2001; 276:2928-34. [PMID: 11032834 DOI: 10.1074/jbc.m007321200] [Citation(s) in RCA: 44] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022] Open
Abstract
Cathepsin B-like cysteine protease genes (cbls) constitute large multigene families in parasitic and nonparasitic nematodes. Although expressed in the intestine of some nematodes, the biological and biochemical functions of the CBL proteins remain unresolved. Di- and tetra-oligopeptides were used as fluorogenic substrates and irreversible/competitive inhibitors to establish CBL functions in the intestine of the parasitic nematode Haemonchus contortus. Cysteine protease activity was detected against diverse substrates including the cathepsin B/L substrate FR, the caspase 1 substrate YVAD, the cathepsin B substrate RR, but not the CED-3 (caspase 3) substrate DEVD. The pH at which maximum activity was detected varied according to substrate and ranged from pH 5.0 to 7.0. Individual CBLs were affinity isolated using FA and YVAD substrates. pH influenced CBL affinity isolation in a substrate-specific manner that paralleled pH effects on individual substrates. N-terminal sequencing identified two isolated CBLs as H. contortus GCP-7 (33 kDa) and AC-4 (37 kDa). N termini of each began at a position consistent with proregion cleavage and protease activation. Isolation of the GCP-7 band by each peptide was preferentially inhibited when competed with a diazomethane-conjugated inhibitor, Z-FA-CHN(2), demonstrating one functional difference among CBLs and among inhibitors. Substrate-based histological analysis placed CBLs on the intestinal microvilli. Data indicate that CBLs are responsible for cysteine protease activity described from H. contortus intestine. Results also support a role of CBLs in nutrient digestion.
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Affiliation(s)
- S Shompole
- Department of Veterinary Microbiology and Pathology, Washington State University, Pullman 99164-7040, USA.
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Mackenzie CD. Human onchocerciasis: the essential partnership between research and disease control efforts. Curr Opin Infect Dis 2000; 13:457-464. [PMID: 11964814 DOI: 10.1097/00001432-200010000-00005] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/27/2022]
Abstract
Twenty years ago onchocerciasis was a disease generally ignored by the medical world, except by those who actually worked with the affected people in Africa and Latin America. Now, largely as a result of the success of mass vector control and drug treatment programs, this is a disease management model for developing countries. The recent literature on onchocerciasis has, not surprisingly, mainly focused on various aspects of control. Investigation into the more basic questions is needed to ensure continued effective disease control. The present mass drug control program is based on a single pharmaceutical, ivermectin (Mectizan), which acts almost exclusively on the microfilarial stage of the infection. Efforts are being made to identify other useful drugs; however, no major candidates have yet appeared. The identification of potential biochemical targets for anti-filarial compounds through a better understanding of the biochemistry of these worms is being pursued. The Onchocerca volvulus endosymbiont Wolbachia may provide a target for therapeutic intervention. An improved understanding of the genomics of O. volvulus has made possible the identification of strain differences in the parasites, and an appreciation of the relevance of these strain differences to the clinical disease, onchocerciasis. There is a need for a better understanding of the clinical disease, and the various pathogenic mechanisms that underly the different syndromes. It is particularly important to understand the pathological basis and mechanisms underlying the adverse responses that can occur with chemotherapy. Present control programs now need to be carefully monitored for effectiveness using new assessment tools, such as antigen assays and the identification of organisms in pools of vectors. Current efforts to control onchocerciasis must be coordinated with new chemotherapy-based control programs for other worm diseases that are emerging. The results of laboratory studies are increasingly being applied to improve the effectiveness of field-based control programs and their assessment. Such research is essential for progress towards the goals of controlling and eliminating onchocerciasis.
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