1
|
Francisco AF, Sousa GR, Vaughan M, Langston H, Khan A, Jayawardhana S, Taylor MC, Lewis MD, Kelly JM. Cardiac Abnormalities in a Predictive Mouse Model of Chagas Disease. Pathogens 2023; 12:1364. [PMID: 38003828 PMCID: PMC10674564 DOI: 10.3390/pathogens12111364] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/13/2023] [Revised: 11/09/2023] [Accepted: 11/16/2023] [Indexed: 11/26/2023] Open
Abstract
Chronic Chagas cardiomyopathy (CCC) results from infection with the protozoan parasite Trypanosoma cruzi and is a prevalent cause of heart disease in endemic countries. We previously found that cardiac fibrosis can vary widely in C3H/HeN mice chronically infected with T. cruzi JR strain, mirroring the spectrum of heart disease in humans. In this study, we examined functional cardiac abnormalities in this host:parasite combination to determine its potential as an experimental model for CCC. We utilised electrocardiography (ECG) to monitor T. cruzi-infected mice and determine whether ECG markers could be correlated with cardiac function abnormalities. We found that the C3H/HeN:JR combination frequently displayed early onset CCC indicators, such as sinus bradycardia and right bundle branch block, as well as prolonged PQ, PR, RR, ST, and QT intervals in the acute stage. Our model exhibited high levels of cardiac inflammation and enhanced iNOS expression in the acute stage, but denervation did not appear to have a role in pathology. These results demonstrate the potential of the C3H/HeN:JR host:parasite combination as a model for CCC that could be used for screening new compounds targeted at cardiac remodelling and for examining the potential of antiparasitic drugs to prevent or alleviate CCC development and progression.
Collapse
Affiliation(s)
- Amanda Fortes Francisco
- Department of Infection Biology, London School of Hygiene and Tropical Medicine, London WC1E 7HT, UK
| | - Giovane R. Sousa
- Harvard Medical School, Section on Immunobiology, Joslin Diabetes Center, 1 Joslin Place, Boston, MA 02215, USA
| | - Mhairi Vaughan
- Research Department of Haematology, Cancer Institute, Faculty of Medical Sciences, University College London, London WC1E 6DD, UK
| | - Harry Langston
- Department of Infection Biology, London School of Hygiene and Tropical Medicine, London WC1E 7HT, UK
| | - Archie Khan
- Department of Infection Biology, London School of Hygiene and Tropical Medicine, London WC1E 7HT, UK
| | - Shiromani Jayawardhana
- Department of Infection Biology, London School of Hygiene and Tropical Medicine, London WC1E 7HT, UK
| | - Martin C. Taylor
- Department of Infection Biology, London School of Hygiene and Tropical Medicine, London WC1E 7HT, UK
| | - Michael D. Lewis
- Department of Infection Biology, London School of Hygiene and Tropical Medicine, London WC1E 7HT, UK
| | - John M. Kelly
- Department of Infection Biology, London School of Hygiene and Tropical Medicine, London WC1E 7HT, UK
| |
Collapse
|
2
|
Jayawardhana S, Ward AI, Francisco AF, Lewis MD, Taylor MC, Kelly JM, Olmo F. Benznidazole treatment leads to DNA damage in Trypanosoma cruzi and the persistence of rare widely dispersed non-replicative amastigotes in mice. PLoS Pathog 2023; 19:e1011627. [PMID: 37956215 PMCID: PMC10681306 DOI: 10.1371/journal.ppat.1011627] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/22/2023] [Revised: 11/27/2023] [Accepted: 10/30/2023] [Indexed: 11/15/2023] Open
Abstract
Benznidazole is the front-line drug used to treat infections with Trypanosoma cruzi, the causative agent of Chagas disease. However, for reasons that are unknown, treatment failures are common. When we examined parasites that survived benznidazole treatment in mice using highly sensitive in vivo and ex vivo bioluminescence imaging, we found that recrudescence is not due to persistence of parasites in a specific organ or tissue that preferentially protects them from drug activity. Surviving parasites are widely distributed and located in host cells where the vast majority contained only one or two amastigotes. Therefore, infection relapse does not arise from a small number of intact large nests. Rather, persisters are either survivors of intracellular populations where co-located parasites have been killed, or amastigotes in single/low-level infected cells exist in a state where they are less susceptible to benznidazole. To better assess the nature of parasite persisters, we exposed infected mammalian cell monolayers to a benznidazole regimen that reduces the intracellular amastigote population to <1% of the pre-treatment level. Of host cells that remained infected, as with the situation in vivo, the vast majority contained only one or two surviving intracellular amastigotes. Analysis, based on non-incorporation of the thymidine analogue EdU, revealed these surviving parasites to be in a transient non-replicative state. Furthermore, treatment with benznidazole led to widespread parasite DNA damage. When the small number of parasites which survive in mice after non-curative treatment were assessed using EdU labelling, this revealed that these persisters were also initially non-replicative. A possible explanation could be that triggering of the T. cruzi DNA damage response pathway by the activity of benznidazole metabolites results in exit from the cell cycle as parasites attempt DNA repair, and that metabolic changes associated with non-proliferation act to reduce drug susceptibility. Alternatively, a small percentage of the parasite population may pre-exist in this non-replicative state prior to treatment.
Collapse
Affiliation(s)
- Shiromani Jayawardhana
- Department of Infection Biology, London School of Hygiene and Tropical Medicine, London, United Kingdom
| | - Alexander I. Ward
- Department of Infection Biology, London School of Hygiene and Tropical Medicine, London, United Kingdom
| | - Amanda F. Francisco
- Department of Infection Biology, London School of Hygiene and Tropical Medicine, London, United Kingdom
| | - Michael D. Lewis
- Department of Infection Biology, London School of Hygiene and Tropical Medicine, London, United Kingdom
| | - Martin C. Taylor
- Department of Infection Biology, London School of Hygiene and Tropical Medicine, London, United Kingdom
| | - John M. Kelly
- Department of Infection Biology, London School of Hygiene and Tropical Medicine, London, United Kingdom
| | - Francisco Olmo
- Department of Infection Biology, London School of Hygiene and Tropical Medicine, London, United Kingdom
| |
Collapse
|
3
|
Racané L, Zlatić K, Cindrić M, Mehić E, Karminski-Zamola G, Taylor MC, Kelly JM, Malić SR, Stojković MR, Kralj M, Hranjec M. Synthesis and Biological Activity of 2-Benzo[b]thienyl and 2-Bithienyl Amidino-Substituted Benzothiazole and Benzimidazole Derivatives. ChemMedChem 2023; 18:e202300261. [PMID: 37376962 DOI: 10.1002/cmdc.202300261] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/11/2023] [Revised: 06/27/2023] [Accepted: 06/27/2023] [Indexed: 06/29/2023]
Abstract
Novel benzo[b]thienyl- and 2,2'-bithienyl-derived benzothiazoles and benzimidazoles were synthesized to study their antiproliferative and antitrypanosomal activities in vitro. Specifically, we assessed the impact that amidine group substitutions and the type of thiophene backbone have on biological activity. In general, the benzothiazole derivatives were more active than their benzimidazole analogs as both antiproliferative and antitrypanosomal agents. The 2,2'-bithienyl-substituted benzothiazoles with unsubstituted and 2-imidazolinyl amidine showed the most potent antitrypanosomal activity, and the greatest selectivity was observed for the benzimidazole derivatives bearing isopropyl, unsubstituted and 2-imidazolinyl amidine. The 2,2'-bithiophene derivatives showed most selective antiproliferative activity. Whereas the all 2,2'-bithienyl-substituted benzothiazoles were selectively active against lung carcinoma, the benzimidazoles were selective against cervical carcinoma cells. The compounds with an unsubstituted amidine group also produced strong antiproliferative effects. The more pronounced antiproliferative activity of the benzothiazole derivatives was attributed to different cytotoxicity mechanisms. Cell cycle analysis, and DNA binding experiments provide evidence that the benzimidazoles target DNA, whereas the benzothiazoles have a different cellular target because they are localized in the cytoplasm and do not interact with DNA.
Collapse
Affiliation(s)
- Livio Racané
- Department of Applied Chemistry, Faculty of Textile Technology, University of Zagreb, Prilaz baruna Filipovića, 10000, Zagreb, Croatia
| | - Katarina Zlatić
- Department of Organic Chemistry, Faculty of Chemical Engineering and Technology, University of Zagreb, Marulićev trg 19, 10000, Zagreb, Croatia
- Division of Molecular Medicine, Ruđer Bošković Institute, Bijenička cesta 54, 10000, Zagreb, Croatia
| | - Maja Cindrić
- Department of Organic Chemistry, Faculty of Chemical Engineering and Technology, University of Zagreb, Marulićev trg 19, 10000, Zagreb, Croatia
| | - Emina Mehić
- Department of Organic Chemistry, Faculty of Chemical Engineering and Technology, University of Zagreb, Marulićev trg 19, 10000, Zagreb, Croatia
| | - Grace Karminski-Zamola
- Department of Organic Chemistry, Faculty of Chemical Engineering and Technology, University of Zagreb, Marulićev trg 19, 10000, Zagreb, Croatia
| | - Martin C Taylor
- Department of Infection Biology, London School of Hygiene and Tropical Medicine, Keppel Street, London, WC1E 7HT, UK
| | - John M Kelly
- Department of Infection Biology, London School of Hygiene and Tropical Medicine, Keppel Street, London, WC1E 7HT, UK
| | - Silvana Raić Malić
- Department of Organic Chemistry, Faculty of Chemical Engineering and Technology, University of Zagreb, Marulićev trg 19, 10000, Zagreb, Croatia
| | - Marijana Radić Stojković
- Division of Organic Chemistry and Biochemistry, Ruđer Bošković Institute, Bijenička cesta 54, 10000, Zagreb, Croatia
| | - Marijeta Kralj
- Division of Molecular Medicine, Ruđer Bošković Institute, Bijenička cesta 54, 10000, Zagreb, Croatia
| | - Marijana Hranjec
- Department of Organic Chemistry, Faculty of Chemical Engineering and Technology, University of Zagreb, Marulićev trg 19, 10000, Zagreb, Croatia
| |
Collapse
|
4
|
Pardali V, Giannakopoulou E, Mpekoulis G, Tsopela V, Panos G, Taylor MC, Kelly JM, Vassilaki N, Zoidis G. Novel Lipophilic Hydroxamates Based on Spirocarbocyclic Hydantoin Scaffolds with Potent Antiviral and Trypanocidal Activity. Pharmaceuticals (Basel) 2023; 16:1046. [PMID: 37513957 PMCID: PMC10385743 DOI: 10.3390/ph16071046] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/13/2023] [Revised: 07/14/2023] [Accepted: 07/18/2023] [Indexed: 07/30/2023] Open
Abstract
Flaviviridae infections, such as those caused by hepatitis C (HCV) and dengue viruses (DENVs), represent global health risks. Infected people are in danger of developing chronic liver failure or hemorrhagic fever, both of which can be fatal if not treated. The tropical parasites Trypanosoma brucei and Trypanosoma cruzi cause enormous socioeconomic burdens in Sub-Saharan Africa and Latin America. Anti-HCV chemotherapy has severe adverse effects and is expensive, whereas dengue has no clinically authorized treatment. Antiparasitic medicines are often toxic and difficult to administer, and treatment failures are widely reported. There is an urgent need for new chemotherapies. Based on our previous research, we have undertaken structural modification of lead compound V with the goal of producing derivatives with both antiviral and trypanocidal activity. The novel spirocarbocyclic-substituted hydantoin analogs were designed, synthesized, and tested for antiviral activity against three HCV genotypes (1b, 3a, 4a), DENV, yellow fever virus (YFV), and two trypanosome species (T. brucei, T. cruzi). The optimization was successful and led to compounds with significant antiviral and trypanocidal activity and exceptional selectivity. Several modifications were made to further investigate the structure-activity relationships (SARs) and confirm the critical role of lipophilicity and conformational degrees of freedom.
Collapse
Affiliation(s)
- Vasiliki Pardali
- School of Health Sciences, Department of Pharmacy, Division of Pharmaceutical Chemistry, National and Kapodistrian University of Athens, Panepistimiopolis Zografou, 15771 Athens, Greece
| | - Erofili Giannakopoulou
- School of Health Sciences, Department of Pharmacy, Division of Pharmaceutical Chemistry, National and Kapodistrian University of Athens, Panepistimiopolis Zografou, 15771 Athens, Greece
| | - George Mpekoulis
- Molecular Virology Laboratory, Hellenic Pasteur Institute, Vas. Sofias Avenue, 11521 Athens, Greece
| | - Vassilina Tsopela
- Molecular Virology Laboratory, Hellenic Pasteur Institute, Vas. Sofias Avenue, 11521 Athens, Greece
| | - Georgios Panos
- Molecular Virology Laboratory, Hellenic Pasteur Institute, Vas. Sofias Avenue, 11521 Athens, Greece
| | - Martin C Taylor
- Department of Infection Biology, London School of Hygiene and Tropical Medicine, Keppel Street, London WC1E 7HT, UK
| | - John M Kelly
- Department of Infection Biology, London School of Hygiene and Tropical Medicine, Keppel Street, London WC1E 7HT, UK
| | - Niki Vassilaki
- Molecular Virology Laboratory, Hellenic Pasteur Institute, Vas. Sofias Avenue, 11521 Athens, Greece
| | - Grigoris Zoidis
- School of Health Sciences, Department of Pharmacy, Division of Pharmaceutical Chemistry, National and Kapodistrian University of Athens, Panepistimiopolis Zografou, 15771 Athens, Greece
| |
Collapse
|
5
|
Martinez MZ, Olmo F, Taylor MC, Caudron F, Wilkinson SR. Dissecting the interstrand crosslink DNA repair system of Trypanosoma cruzi. DNA Repair (Amst) 2023; 125:103485. [PMID: 36989950 DOI: 10.1016/j.dnarep.2023.103485] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/17/2023] [Revised: 03/08/2023] [Accepted: 03/13/2023] [Indexed: 03/18/2023]
Abstract
DNA interstrand crosslinks (ICLs) are toxic lesions that can block essential biological processes. Here we show Trypanosoma cruzi, the causative agent of Chagas disease, is susceptible to ICL-inducing compounds including mechlorethamine and novel nitroreductase-activated prodrugs that have potential in treating this infection. To resolve such lesions, cells co-opt enzymes from "classical" DNA repair pathways that alongside dedicated factors operate in replication-dependent and -independent mechanisms. To assess ICL repair in T. cruzi, orthologues of SNM1, MRE11 and CSB were identified and their function assessed. The T. cruzi enzymes could complement the mechlorethamine susceptibility phenotype displayed by corresponding yeast and/or T. brucei null confirming their role as ICL repair factors while GFP-tagged TcSNM1, TcMRE11 and TcCSB were shown to localise to the nuclei of insect and/or intracellular form parasites. Gene disruption demonstrated that while each activity was non-essential for T. cruzi viability, nulls displayed a growth defect in at least one life cycle stage with TcMRE11-deficient trypomastigotes also compromised in mammalian cell infectivity. Phenotyping revealed all nulls were more susceptible to mechlorethamine than controls, a trait complemented by re-expression of the deleted gene. To assess interplay, the gene disruption approach was extended to generate T. cruzi deficient in TcSNM1/TcMRE11 or in TcSNM1/TcCSB. Analysis demonstrated these activities functioned across two ICL repair pathways with TcSNM1 and TcMRE11 postulated to operate in a replication-dependent system while TcCSB helps resolve transcription-blocking lesions. By unravelling how T. cruzi repairs ICL damage, specific inhibitors targeting repair components could be developed and used to increase the potency of trypanocidal ICL-inducing compounds.
Collapse
Affiliation(s)
- Monica Zavala Martinez
- School of Biological & Chemical Sciences, Queen Mary University of London, Mile End Road, London E1 4NS, UK
| | - Francisco Olmo
- Department of Infection Biology, London School of Hygiene and Tropical Medicine, Keppel Street, London WC1E 7HT, UK
| | - Martin C Taylor
- Department of Infection Biology, London School of Hygiene and Tropical Medicine, Keppel Street, London WC1E 7HT, UK
| | - Fabrice Caudron
- School of Biological & Chemical Sciences, Queen Mary University of London, Mile End Road, London E1 4NS, UK
| | - Shane R Wilkinson
- School of Biological & Chemical Sciences, Queen Mary University of London, Mile End Road, London E1 4NS, UK.
| |
Collapse
|
6
|
Macleod OJS, Cook AD, Webb H, Crow M, Burns R, Redpath M, Seisenberger S, Trevor CE, Peacock L, Schwede A, Kimblin N, Francisco AF, Pepperl J, Rust S, Voorheis P, Gibson W, Taylor MC, Higgins MK, Carrington M. Invariant surface glycoprotein 65 of Trypanosoma brucei is a complement C3 receptor. Nat Commun 2022; 13:5085. [PMID: 36038546 PMCID: PMC9424271 DOI: 10.1038/s41467-022-32728-9] [Citation(s) in RCA: 11] [Impact Index Per Article: 5.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/19/2021] [Accepted: 08/10/2022] [Indexed: 11/16/2022] Open
Abstract
African trypanosomes are extracellular pathogens of mammals and are exposed to the adaptive and innate immune systems. Trypanosomes evade the adaptive immune response through antigenic variation, but little is known about how they interact with components of the innate immune response, including complement. Here we demonstrate that an invariant surface glycoprotein, ISG65, is a receptor for complement component 3 (C3). We show how ISG65 binds to the thioester domain of C3b. We also show that C3 contributes to control of trypanosomes during early infection in a mouse model and provide evidence that ISG65 is involved in reducing trypanosome susceptibility to C3-mediated clearance. Deposition of C3b on pathogen surfaces, such as trypanosomes, is a central point in activation of the complement system. In ISG65, trypanosomes have evolved a C3 receptor which diminishes the downstream effects of C3 deposition on the control of infection. Trypanosomes evade the immune response through antigenic variation of a surface coat containing variant surface glycoproteins (VSG). They also express invariant surface glycoproteins (ISGs), which are less well understood. Here, Macleod et al. show that ISG65 of T. brucei is a receptor for complement component 3. They provide the crystal structure of T. brucei ISG65 in complex with complement C3d and show evidence that ISG65 is involved in reducing trypanosome susceptibility to C3-mediated clearance in vivo.
Collapse
Affiliation(s)
- Olivia J S Macleod
- Department of Biochemistry, University of Cambridge, Tennis Court Road, Cambridge, CB2 1QW, UK
| | - Alexander D Cook
- Department of Biochemistry, University of Oxford, South Parks Road, Oxford, OX1 3QU, UK.,Kavli Institute for Nanoscience Discovery, Dorothy Crowfoot Hodgkin Building, University of Oxford, South Parks Road, Oxford, OX1 3QU, UK
| | - Helena Webb
- Department of Biochemistry, University of Cambridge, Tennis Court Road, Cambridge, CB2 1QW, UK
| | - Mandy Crow
- Department of Biochemistry, University of Cambridge, Tennis Court Road, Cambridge, CB2 1QW, UK
| | - Roisin Burns
- Department of Biochemistry, University of Cambridge, Tennis Court Road, Cambridge, CB2 1QW, UK
| | - Maria Redpath
- Department of Biochemistry, University of Cambridge, Tennis Court Road, Cambridge, CB2 1QW, UK
| | - Stefanie Seisenberger
- Department of Biochemistry, University of Cambridge, Tennis Court Road, Cambridge, CB2 1QW, UK
| | - Camilla E Trevor
- Department of Biochemistry, University of Cambridge, Tennis Court Road, Cambridge, CB2 1QW, UK
| | - Lori Peacock
- Bristol Veterinary School and School of Biological Sciences, University of Bristol, Bristol, UK
| | - Angela Schwede
- Department of Biochemistry, University of Cambridge, Tennis Court Road, Cambridge, CB2 1QW, UK
| | - Nicola Kimblin
- Department of Biochemistry, University of Cambridge, Tennis Court Road, Cambridge, CB2 1QW, UK
| | - Amanda F Francisco
- Faculty of Infectious and Tropical Diseases, London School of Hygiene and Tropical Medicine, London, WC1E 7HT, UK
| | - Julia Pepperl
- Department of Biochemistry, University of Cambridge, Tennis Court Road, Cambridge, CB2 1QW, UK
| | - Steve Rust
- Antibody Discovery and Protein Engineering, Biopharmaceuticals R&D, AstraZeneca, Cambridge, UK
| | - Paul Voorheis
- School of Biochemistry and Immunology, Trinity Biomedical Sciences Institute, Trinity College Dublin, Dublin, Ireland
| | - Wendy Gibson
- Bristol Veterinary School and School of Biological Sciences, University of Bristol, Bristol, UK
| | - Martin C Taylor
- Faculty of Infectious and Tropical Diseases, London School of Hygiene and Tropical Medicine, London, WC1E 7HT, UK
| | - Matthew K Higgins
- Department of Biochemistry, University of Oxford, South Parks Road, Oxford, OX1 3QU, UK. .,Kavli Institute for Nanoscience Discovery, Dorothy Crowfoot Hodgkin Building, University of Oxford, South Parks Road, Oxford, OX1 3QU, UK.
| | - Mark Carrington
- Department of Biochemistry, University of Cambridge, Tennis Court Road, Cambridge, CB2 1QW, UK.
| |
Collapse
|
7
|
Abacha YZ, Forkuo AD, Gbedema SY, Mittal N, Ottilie S, Rocamora F, Winzeler EA, van Schalkwyk DA, Kelly JM, Taylor MC, Reader J, Birkholtz LM, Lisgarten DR, Cockcroft JK, Lisgarten JN, Palmer RA, Talbert RC, Shnyder SD, Wright CW. Semi-Synthetic Analogues of Cryptolepine as a Potential Source of Sustainable Drugs for the Treatment of Malaria, Human African Trypanosomiasis, and Cancer. Front Pharmacol 2022; 13:875647. [PMID: 35600849 PMCID: PMC9119314 DOI: 10.3389/fphar.2022.875647] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/14/2022] [Accepted: 03/08/2022] [Indexed: 12/11/2022] Open
Abstract
The prospect of eradicating malaria continues to be challenging in the face of increasing parasite resistance to antimalarial drugs so that novel antimalarials active against asexual, sexual, and liver-stage malaria parasites are urgently needed. In addition, new antimalarials need to be affordable and available to those most in need and, bearing in mind climate change, should ideally be sustainable. The West African climbing shrub Cryptolepis sanguinolenta is used traditionally for the treatment of malaria; its principal alkaloid, cryptolepine (1), has been shown to have antimalarial properties, and the synthetic analogue 2,7-dibromocryptolepine (2) is of interest as a lead toward new antimalarial agents. Cryptolepine (1) was isolated using a two-step Soxhlet extraction of C. sanguinolenta roots, followed by crystallization (yield 0.8% calculated as a base with respect to the dried roots). Semi-synthetic 7-bromo- (3), 7, 9-dibromo- (4), 7-iodo- (5), and 7, 9-dibromocryptolepine (6) were obtained in excellent yields by reaction of 1 with N-bromo- or N-iodosuccinimide in trifluoroacetic acid as a solvent. All compounds were active against Plasmodia in vitro, but 6 showed the most selective profile with respect to Hep G2 cells: P. falciparum (chloroquine-resistant strain K1), IC50 = 0.25 µM, SI = 113; late stage, gametocytes, IC50 = 2.2 µM, SI = 13; liver stage, P. berghei sporozoites IC50 = 6.13 µM, SI = 4.6. Compounds 3-6 were also active against the emerging zoonotic species P. knowlesi with 5 being the most potent (IC50 = 0.11 µM). In addition, 3-6 potently inhibited T. brucei in vitro at nM concentrations and good selectivity with 6 again being the most selective (IC50 = 59 nM, SI = 478). These compounds were also cytotoxic to wild-type ovarian cancer cells as well as adriamycin-resistant and, except for 5, cisplatin-resistant ovarian cancer cells. In an acute oral toxicity test in mice, 3-6 did not exhibit toxic effects at doses of up to 100 mg/kg/dose × 3 consecutive days. This study demonstrates that C. sanguinolenta may be utilized as a sustainable source of novel compounds that may lead to the development of novel agents for the treatment of malaria, African trypanosomiasis, and cancer.
Collapse
Affiliation(s)
- Yabalu Z. Abacha
- School of Pharmacy and Medical Sciences, University of Bradford, Bradford, United Kingdom,Department of Pharmacognosy, Faculty of Pharmacy, University of Maiduguri, Maiduguri, Nigeria
| | - Arnold Donkor Forkuo
- Department of Pharmacology, Faculty of Pharmacy and Pharmaceutical Sciences, College of Health Sciences, Kwame Nkrumah University of Science and Technology (KNUST), Kumasi, Ghana
| | - Stephen Y. Gbedema
- Department of Pharmaceutics, Faculty of Pharmacy and Pharmaceutical Sciences, College of Health Sciences, KNUST, Kumasi, Ghana
| | - Nimisha Mittal
- Malaria Drug Accelerator (MalDA) Consortium, School of Medicine, University of California, San Diego, La Jolla, CA, United States
| | - Sabine Ottilie
- Malaria Drug Accelerator (MalDA) Consortium, School of Medicine, University of California, San Diego, La Jolla, CA, United States
| | - Frances Rocamora
- Malaria Drug Accelerator (MalDA) Consortium, School of Medicine, University of California, San Diego, La Jolla, CA, United States
| | - Elizabeth A. Winzeler
- Malaria Drug Accelerator (MalDA) Consortium, School of Medicine, University of California, San Diego, La Jolla, CA, United States
| | - Donelly A. van Schalkwyk
- Department of Infection Biology, Faculty of Infectious and Tropical Diseases, London School of Hygiene and Tropical Medicine, London, United Kingdom
| | - John M. Kelly
- Department of Infection Biology, Faculty of Infectious and Tropical Diseases, London School of Hygiene and Tropical Medicine, London, United Kingdom
| | - Martin C. Taylor
- Department of Infection Biology, Faculty of Infectious and Tropical Diseases, London School of Hygiene and Tropical Medicine, London, United Kingdom
| | - Janette Reader
- Department of Biochemistry, Genetics and Microbiology, Faculty of Natural and Agricultural Sciences, Institute for Sustainable Malaria Control, University of Pretoria, Hatfield, South Africa
| | - Lyn-Marie Birkholtz
- Department of Biochemistry, Genetics and Microbiology, Faculty of Natural and Agricultural Sciences, Institute for Sustainable Malaria Control, University of Pretoria, Hatfield, South Africa
| | - David R. Lisgarten
- Biomolecular Research Group, School of Psychology and Life Sciences, Canterbury Christ Church University, Canterbury, United Kingdom
| | - Jeremy K. Cockcroft
- Department of Chemistry, Christopher Ingold Laboratories, University College London, London, United Kingdom
| | | | - Rex A. Palmer
- Department of Crystallography, Biochemical Sciences, Birkbeck College, University of London, London, United Kingdom
| | - Rosemary C. Talbert
- Biomolecular Research Group, School of Psychology and Life Sciences, Canterbury Christ Church University, Canterbury, United Kingdom
| | - Steven D. Shnyder
- School of Pharmacy and Medical Sciences, Institute of Cancer Therapeutics, University of Bradford, Bradford, United Kingdom
| | - Colin W. Wright
- School of Pharmacy and Medical Sciences, University of Bradford, Bradford, United Kingdom,*Correspondence: Colin W. Wright,
| |
Collapse
|
8
|
Ward AI, Lewis MD, Taylor MC, Kelly JM. Incomplete Recruitment of Protective T Cells Is Associated with Trypanosoma cruzi Persistence in the Mouse Colon. Infect Immun 2022; 90:e0038221. [PMID: 34780279 PMCID: PMC8853677 DOI: 10.1128/iai.00382-21] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/06/2021] [Accepted: 11/08/2021] [Indexed: 11/24/2022] Open
Abstract
Trypanosoma cruzi is the etiological agent of Chagas disease. Following T cell-mediated suppression of acute-phase infection, this intracellular eukaryotic pathogen persists long-term in a limited subset of tissues at extremely low levels. The reasons for this tissue-specific chronicity are not understood. Using a dual bioluminescent-fluorescent reporter strain and highly sensitive tissue imaging that allows experimental infections to be monitored at single-cell resolution, we undertook a systematic analysis of the immunological microenvironments of rare parasitized cells in the mouse colon, a key site of persistence. We demonstrate that incomplete recruitment of T cells to a subset of colonic infection foci permits the occurrence of repeated cycles of intracellular parasite replication and differentiation to motile trypomastigotes at a frequency sufficient to perpetuate chronic infections. The lifelong persistence of parasites in this tissue site continues despite the presence, at a systemic level, of a highly effective T cell response. Overcoming this low-level dynamic host-parasite equilibrium represents a major challenge for vaccine development.
Collapse
Affiliation(s)
- Alexander I. Ward
- Department of Infection Biology, London School of Hygiene and Tropical Medicine, London, United Kingdom
| | - Michael D. Lewis
- Department of Infection Biology, London School of Hygiene and Tropical Medicine, London, United Kingdom
| | - Martin C. Taylor
- Department of Infection Biology, London School of Hygiene and Tropical Medicine, London, United Kingdom
| | - John M. Kelly
- Department of Infection Biology, London School of Hygiene and Tropical Medicine, London, United Kingdom
| |
Collapse
|
9
|
Moreno-Vicente J, Willoughby JE, Taylor MC, Booth SG, English VL, Williams EL, Penfold CA, Mockridge CI, Inzhelevskaya T, Kim J, Chan HTC, Cragg MS, Gray JC, Beers SA. Fc-null anti-PD-1 monoclonal antibodies deliver optimal checkpoint blockade in diverse immune environments. J Immunother Cancer 2022; 10:e003735. [PMID: 35017153 PMCID: PMC8753441 DOI: 10.1136/jitc-2021-003735] [Citation(s) in RCA: 11] [Impact Index Per Article: 5.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 12/08/2021] [Indexed: 12/14/2022] Open
Abstract
BACKGROUND Despite extensive clinical use, the mechanisms that lead to therapeutic resistance to anti-programmed cell-death (PD)-1 monoclonal antibodies (mAbs) remain elusive. Here, we sought to determine how interactions between the Fc region of anti-PD-1 mAbs and Fcγ receptors (FcγRs) affect therapeutic activity and how these are impacted by the immune environment. METHODS Mouse and human anti-PD-1 mAbs with different Fc binding profiles were generated and characterized in vitro. The ability of these mAbs to elicit T-cell responses in vivo was first assessed in a vaccination setting using the model antigen ovalbumin. The antitumor activity of anti-PD-1 mAbs was investigated in the context of immune 'hot' MC38 versus 'cold' neuroblastoma tumor models, and flow cytometry performed to assess immune infiltration. RESULTS Engagement of activating FcγRs by anti-PD-1 mAbs led to depletion of activated CD8 T cells in vitro and in vivo, abrogating therapeutic activity. Importantly, the extent of this Fc-mediated modulation was determined by the surrounding immune environment. Low FcγR-engaging mouse anti-PD-1 isotypes, which are frequently used as surrogates for human mAbs, were unable to expand ovalbumin-reactive CD8 T cells, in contrast to Fc-null mAbs. These results were recapitulated in mice expressing human FcγRs, in which clinically relevant hIgG4 anti-PD-1 led to reduced endogenous expansion of CD8 T cells compared with its engineered Fc-null counterpart. In the context of an immunologically 'hot' tumor however, both low-engaging and Fc-null mAbs induced long-term antitumor immunity in MC38-bearing mice. Finally, a similar anti-PD-1 isotype hierarchy was demonstrated in the less responsive 'cold' 9464D neuroblastoma model, where the most effective mAbs were able to delay tumor growth but could not induce long-term protection. CONCLUSIONS Our data collectively support a critical role for Fc:FcγR interactions in inhibiting immune responses to both mouse and human anti-PD-1 mAbs, and highlight the context-dependent effect that anti-PD-1 mAb isotypes can have on T-cell responses. We propose that engineering of Fc-null anti-PD-1 mAbs would prevent FcγR-mediated resistance in vivo and allow maximal T-cell stimulation independent of the immunological environment.
Collapse
Affiliation(s)
- Julia Moreno-Vicente
- Antibody and Vaccine Group, Centre for Cancer Immunology, Cancer Sciences, University of Southampton, Southampton, UK
- Cancer Research UK Cambridge Institute, University of Cambridge, Cambridge, UK
| | - Jane E Willoughby
- Antibody and Vaccine Group, Centre for Cancer Immunology, Cancer Sciences, University of Southampton, Southampton, UK
| | - Martin C Taylor
- Antibody and Vaccine Group, Centre for Cancer Immunology, Cancer Sciences, University of Southampton, Southampton, UK
| | - Steven G Booth
- Antibody and Vaccine Group, Centre for Cancer Immunology, Cancer Sciences, University of Southampton, Southampton, UK
| | - Vikki L English
- Antibody and Vaccine Group, Centre for Cancer Immunology, Cancer Sciences, University of Southampton, Southampton, UK
| | - Emily L Williams
- Antibody and Vaccine Group, Centre for Cancer Immunology, Cancer Sciences, University of Southampton, Southampton, UK
| | - Christine A Penfold
- Antibody and Vaccine Group, Centre for Cancer Immunology, Cancer Sciences, University of Southampton, Southampton, UK
| | - C Ian Mockridge
- Antibody and Vaccine Group, Centre for Cancer Immunology, Cancer Sciences, University of Southampton, Southampton, UK
| | - Tatyana Inzhelevskaya
- Antibody and Vaccine Group, Centre for Cancer Immunology, Cancer Sciences, University of Southampton, Southampton, UK
| | - Jinny Kim
- Antibody and Vaccine Group, Centre for Cancer Immunology, Cancer Sciences, University of Southampton, Southampton, UK
| | - H T Claude Chan
- Antibody and Vaccine Group, Centre for Cancer Immunology, Cancer Sciences, University of Southampton, Southampton, UK
| | - Mark S Cragg
- Antibody and Vaccine Group, Centre for Cancer Immunology, Cancer Sciences, University of Southampton, Southampton, UK
| | - Juliet C Gray
- Antibody and Vaccine Group, Centre for Cancer Immunology, Cancer Sciences, University of Southampton, Southampton, UK
| | - Stephen A Beers
- Antibody and Vaccine Group, Centre for Cancer Immunology, Cancer Sciences, University of Southampton, Southampton, UK
| |
Collapse
|
10
|
Racané L, Rep V, Kraljević Pavelić S, Grbčić P, Zonjić I, Radić Stojković M, Taylor MC, Kelly JM, Raić-Malić S. Synthesis, antiproliferative and antitrypanosomal activities, and DNA binding of novel 6-amidino-2-arylbenzothiazoles. J Enzyme Inhib Med Chem 2021; 36:1952-1967. [PMID: 34455887 PMCID: PMC8409973 DOI: 10.1080/14756366.2021.1959572] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/27/2022] Open
Abstract
A series of 6-amidinobenzothiazoles, linked via phenoxymethylene or directly to the 1,2,3-triazole ring with a p-substituted phenyl or benzyl moiety, were synthesised and evaluated in vitro against four human tumour cell lines and the protozoan parasite Trypanosoma brucei. The influence of the type of amidino substituent and phenoxymethylene linker on antiproliferative and antitrypanosomal activities was observed, showing that the imidazoline moiety had a major impact on both activities. Benzothiazole imidazoline 14a, which was directly connected to N-1-phenyl-1,2,3-triazole, had the most potent growth-inhibitory effect (IC50 = 0.25 µM) on colorectal adenocarcinoma (SW620), while benzothiazole imidazoline 11b, containing a phenoxymethylene linker, exhibited the best antitrypanosomal potency (IC90 = 0.12 µM). DNA binding assays showed a non-covalent interaction of 6-amidinobenzothiazole ligands, indicating both minor groove binding and intercalation modes of DNA interaction. Our findings encourage further development of novel structurally related 6-amidino-2-arylbenzothiazoles to obtain more selective anticancer and anti-HAT agents.
Collapse
Affiliation(s)
- Livio Racané
- Faculty of Textile Technology, Department of Applied Chemistry, University of Zagreb, Zagreb, Croatia
| | - Valentina Rep
- Faculty of Chemical Engineering and Technology, Department of Organic Chemistry, University of Zagreb, Zagreb, Croatia
| | | | - Petra Grbčić
- Faculty of Health Studies, University of Rijeka, Rijeka, Croatia
| | - Iva Zonjić
- Division of Organic Chemistry and Biochemistry, Ruđer Bošković Institute, Zagreb, Croatia
| | | | - Martin C Taylor
- Department of Infection Biology, London School of Hygiene and Tropical Medicine, London, UK
| | - John M Kelly
- Department of Infection Biology, London School of Hygiene and Tropical Medicine, London, UK
| | - Silvana Raić-Malić
- Faculty of Chemical Engineering and Technology, Department of Organic Chemistry, University of Zagreb, Zagreb, Croatia
| |
Collapse
|
11
|
Khan AA, Langston HC, Costa FC, Olmo F, Taylor MC, McCann CJ, Kelly JM, Lewis MD. Local association of Trypanosoma cruzi chronic infection foci and enteric neuropathic lesions at the tissue micro-domain scale. PLoS Pathog 2021; 17:e1009864. [PMID: 34424944 PMCID: PMC8412264 DOI: 10.1371/journal.ppat.1009864] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/14/2021] [Revised: 09/02/2021] [Accepted: 08/04/2021] [Indexed: 11/19/2022] Open
Abstract
Digestive Chagas disease (DCD) is an enteric neuropathy caused by Trypanosoma cruzi infection. The mechanism of pathogenesis is poorly understood and the lack of a robust, predictive animal model has held back research. We screened a series of mouse models using gastrointestinal tracer assays and in vivo infection imaging systems to discover a subset exhibiting chronic digestive transit dysfunction and significant retention of faeces in both sated and fasted conditions. The colon was a specific site of both tissue parasite persistence, delayed transit and dramatic loss of myenteric neurons as revealed by whole-mount immunofluorescence analysis. DCD mice therefore recapitulated key clinical manifestations of human disease. We also exploited dual reporter transgenic parasites to home in on locations of rare chronic infection foci in the colon by ex vivo bioluminescence imaging and then used fluorescence imaging in tissue microdomains to reveal co-localisation of infection and enteric nervous system lesions. This indicates that long-term T. cruzi-host interactions in the colon drive DCD pathogenesis, suggesting that the efficacy of anti-parasitic chemotherapy against chronic disease progression warrants further pre-clinical investigation. Chagas disease (American trypanosomiasis) is caused by the protozoan parasite Trypanosoma cruzi. Chagas disease has two types, the cardiac form and the digestive form; some patients have symptoms of both. How the parasite causes digestive disease is poorly understood. It is known that damage to the gut’s nervous system is an important factor, but it has been unclear exactly where and when this damage occurs during the course of an infection and also why only a subset of infected people suffer from this outcome. We studied infections in mice and found certain combinations of strains of parasites and mice that exhibited symptoms similar to human digestive Chagas patients, including a problem with peristalsis that localised specifically to the colon. Using parasites that were genetically engineered to emit both bioluminescent and fluorescent light, we tracked infections over time and were able to analyse rare infected cells deep within the muscle tissue of the wall of the colon. We found evidence of damaged neurons in the same location as these infection foci over 6 months after initial infection. Our results show that digestive Chagas disease probably develops as a result of chronic infection and inflammation, which potentially changes approaches to treatment.
Collapse
Affiliation(s)
- Archie A. Khan
- Department of Infection Biology, London School of Hygiene and Tropical Medicine, London, United Kingdom
| | - Harry C. Langston
- Department of Infection Biology, London School of Hygiene and Tropical Medicine, London, United Kingdom
| | - Fernanda C. Costa
- Department of Infection Biology, London School of Hygiene and Tropical Medicine, London, United Kingdom
| | - Francisco Olmo
- Department of Infection Biology, London School of Hygiene and Tropical Medicine, London, United Kingdom
| | - Martin C. Taylor
- Department of Infection Biology, London School of Hygiene and Tropical Medicine, London, United Kingdom
| | - Conor J. McCann
- Stem Cells and Regenerative Medicine, University College London, Institute of Child Health, London, United Kingdom
| | - John M. Kelly
- Department of Infection Biology, London School of Hygiene and Tropical Medicine, London, United Kingdom
| | - Michael D. Lewis
- Department of Infection Biology, London School of Hygiene and Tropical Medicine, London, United Kingdom
- * E-mail:
| |
Collapse
|
12
|
Taylor MC, Ward AI, Olmo F, Francisco AF, Jayawardhana S, Costa FC, Lewis MD, Kelly JM. Bioluminescent:Fluorescent Trypanosoma cruzi Reporter Strains as Tools for Exploring Chagas Disease Pathogenesis and Drug Activity. Curr Pharm Des 2021; 27:1733-1740. [PMID: 33234096 DOI: 10.2174/1381612826666201124113214] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/07/2020] [Revised: 07/16/2020] [Accepted: 07/23/2020] [Indexed: 11/22/2022]
Abstract
Chagas disease results from infection with the trypanosomatid parasite Trypanosoma cruzi. Progress in developing new drugs has been hampered by the long term and complex nature of the condition and by our limited understanding of parasite biology. Technical difficulties in assessing the parasite burden during the chronic stage of infection have also proven to be a particular challenge. In this context, the development of noninvasive, highly sensitive bioluminescence imaging procedures based on parasites that express a red-shifted luciferase has greatly enhanced our ability to monitor infections in experimental models. Applications of this methodology have led to new insights into tissue tropism and infection dynamics and have been a major driver in drug development. The system has been further modified by the generation of parasite reporter lines that express bioluminescent:fluorescent fusion proteins, an advancement that has allowed chronic infections in mice to be examined at a cellular level. By exploiting bioluminescence, to identify the rare sites of tissue infection, and fluorescence to detect T. cruzi at the level of individual host cells in histological sections, it has been possible to investigate the replication and differentiation status of parasites in vivo and to examine the cellular environment of infection foci. In combination, these data provide a framework for the detailed dissection of disease pathogenesis and drug activity.
Collapse
Affiliation(s)
- Martin C Taylor
- Department of Infection Biology, London School of Hygiene and Tropical Medicine, Keppel Street, London WC1E 7HT, United Kingdom
| | - Alexander I Ward
- Department of Infection Biology, London School of Hygiene and Tropical Medicine, Keppel Street, London WC1E 7HT, United Kingdom
| | - Francisco Olmo
- Department of Infection Biology, London School of Hygiene and Tropical Medicine, Keppel Street, London WC1E 7HT, United Kingdom
| | - Amanda F Francisco
- Department of Infection Biology, London School of Hygiene and Tropical Medicine, Keppel Street, London WC1E 7HT, United Kingdom
| | - Shiromani Jayawardhana
- Department of Infection Biology, London School of Hygiene and Tropical Medicine, Keppel Street, London WC1E 7HT, United Kingdom
| | - Fernanda C Costa
- Department of Infection Biology, London School of Hygiene and Tropical Medicine, Keppel Street, London WC1E 7HT, United Kingdom
| | - Michael D Lewis
- Department of Infection Biology, London School of Hygiene and Tropical Medicine, Keppel Street, London WC1E 7HT, United Kingdom
| | - John M Kelly
- Department of Infection Biology, London School of Hygiene and Tropical Medicine, Keppel Street, London WC1E 7HT, United Kingdom
| |
Collapse
|
13
|
Ward AI, Olmo F, Atherton RL, Taylor MC, Kelly JM. Trypanosoma cruzi amastigotes that persist in the colon during chronic stage murine infections have a reduced replication rate. Open Biol 2020; 10:200261. [PMID: 33321060 PMCID: PMC7776577 DOI: 10.1098/rsob.200261] [Citation(s) in RCA: 18] [Impact Index Per Article: 4.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/13/2022] Open
Abstract
Chronic Trypanosoma cruzi infections are typically lifelong, with small numbers of parasites surviving in restricted tissue sites, which include the gastrointestinal tract. There is considerable debate about the replicative status of these persistent parasites and whether there is a role for dormancy in long-term infection. Here, we investigated T. cruzi proliferation in the colon of chronically infected mice using 5-ethynyl-2′deoxyuridine incorporation into DNA to provide ‘snapshots’ of parasite replication status. Highly sensitive imaging of the extremely rare infection foci, at single-cell resolution, revealed that parasites are three times more likely to be in S-phase during the acute stage than during the chronic stage. By implication, chronic infections of the colon are associated with a reduced rate of parasite replication. Despite this, very few host cells survived infection for more than 14 days, suggesting that T. cruzi persistence continues to involve regular cycles of replication, host cell lysis and re-infection. We could find no evidence for wide-spread dormancy in parasites that persist in this tissue reservoir.
Collapse
Affiliation(s)
- Alexander I Ward
- Department of Infection Biology, London School of Hygiene and Tropical Medicine, London, UK
| | - Francisco Olmo
- Department of Infection Biology, London School of Hygiene and Tropical Medicine, London, UK
| | - Richard L Atherton
- Department of Infection Biology, London School of Hygiene and Tropical Medicine, London, UK
| | - Martin C Taylor
- Department of Infection Biology, London School of Hygiene and Tropical Medicine, London, UK
| | - John M Kelly
- Department of Infection Biology, London School of Hygiene and Tropical Medicine, London, UK
| |
Collapse
|
14
|
Francisco AF, Jayawardhana S, Olmo F, Lewis MD, Wilkinson SR, Taylor MC, Kelly JM. Challenges in Chagas Disease Drug Development. Molecules 2020; 25:E2799. [PMID: 32560454 PMCID: PMC7355550 DOI: 10.3390/molecules25122799] [Citation(s) in RCA: 24] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/22/2020] [Revised: 06/11/2020] [Accepted: 06/12/2020] [Indexed: 02/08/2023] Open
Abstract
The protozoan parasite Trypanosoma cruzi causes Chagas disease, an important public health problem throughout Latin America. Current therapeutic options are characterised by limited efficacy, long treatment regimens and frequent toxic side-effects. Advances in this area have been compromised by gaps in our knowledge of disease pathogenesis, parasite biology and drug activity. Nevertheless, several factors have come together to create a more optimistic scenario. Drug-based research has become more systematic, with increased collaborations between the academic and commercial sectors, often within the framework of not-for-profit consortia. High-throughput screening of compound libraries is being widely applied, and new technical advances are helping to streamline the drug development pipeline. In addition, drug repurposing and optimisation of current treatment regimens, informed by laboratory research, are providing a basis for new clinical trials. Here, we will provide an overview of the current status of Chagas disease drug development, highlight those areas where progress can be expected, and describe how fundamental research is helping to underpin the process.
Collapse
Affiliation(s)
- Amanda F. Francisco
- Department of Infection Biology, London School of Hygiene and Tropical Medicine Keppel Street, London WC1E 7HT, UK; (A.F.F.); (S.J.); (F.O.); (M.D.L.); (M.C.T.)
| | - Shiromani Jayawardhana
- Department of Infection Biology, London School of Hygiene and Tropical Medicine Keppel Street, London WC1E 7HT, UK; (A.F.F.); (S.J.); (F.O.); (M.D.L.); (M.C.T.)
| | - Francisco Olmo
- Department of Infection Biology, London School of Hygiene and Tropical Medicine Keppel Street, London WC1E 7HT, UK; (A.F.F.); (S.J.); (F.O.); (M.D.L.); (M.C.T.)
| | - Michael D. Lewis
- Department of Infection Biology, London School of Hygiene and Tropical Medicine Keppel Street, London WC1E 7HT, UK; (A.F.F.); (S.J.); (F.O.); (M.D.L.); (M.C.T.)
| | - Shane R. Wilkinson
- School of Biological and Chemical Sciences, Queen Mary University of London Mile End Road, London E1 4NS, UK;
| | - Martin C. Taylor
- Department of Infection Biology, London School of Hygiene and Tropical Medicine Keppel Street, London WC1E 7HT, UK; (A.F.F.); (S.J.); (F.O.); (M.D.L.); (M.C.T.)
| | - John M. Kelly
- Department of Infection Biology, London School of Hygiene and Tropical Medicine Keppel Street, London WC1E 7HT, UK; (A.F.F.); (S.J.); (F.O.); (M.D.L.); (M.C.T.)
| |
Collapse
|
15
|
Pardali V, Giannakopoulou E, Balourdas DI, Myrianthopoulos V, Taylor MC, Šekutor M, Mlinarić-Majerski K, Kelly JM, Zoidis G. Lipophilic Guanylhydrazone Analogues as Promising Trypanocidal Agents: An Extended SAR Study. Curr Pharm Des 2020; 26:838-866. [DOI: 10.2174/1381612826666200210150127] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/02/2019] [Accepted: 11/19/2019] [Indexed: 12/18/2022]
Abstract
In this report, we extend the SAR analysis of a number of lipophilic guanylhydrazone analogues with
respect to in vitro growth inhibition of Trypanosoma brucei and Trypanosoma cruzi. Sleeping sickness and Chagas
disease, caused by the tropical parasites T. brucei and T. cruzi, constitute a significant socioeconomic burden
in low-income countries of sub-Saharan Africa and Latin America, respectively. Drug development is underfunded.
Moreover, current treatments are outdated and difficult to administer, while drug resistance is an emerging
concern. The synthesis of adamantane-based compounds that have potential as antitrypanosomal agents is
extensively reviewed. The critical role of the adamantane ring was further investigated by synthesizing and testing
a number of novel lipophilic guanylhydrazones. The introduction of hydrophobic bulky substituents onto the
adamantane ring generated the most active analogues, illustrating the synergistic effect of the lipophilic character
of the C1 side chain and guanylhydrazone moiety on trypanocidal activity. The n-decyl C1-substituted compound
G8 proved to be the most potent adamantane derivative against T. brucei with activity in the nanomolar range
(EC50=90 nM). Molecular simulations were also performed to better understand the structure-activity relationships
between the studied guanylhydrazone analogues and their potential enzyme target.
Collapse
Affiliation(s)
- Vasiliki Pardali
- School of Health Sciences, Department of Pharmacy, Division of Pharmaceutical Chemistry, National and Kapodistrian University of Athens, Panepistimiopolis-Zografou, GR-15771 Athens, Greece
| | - Erofili Giannakopoulou
- School of Health Sciences, Department of Pharmacy, Division of Pharmaceutical Chemistry, National and Kapodistrian University of Athens, Panepistimiopolis-Zografou, GR-15771 Athens, Greece
| | - Dimitrios-Ilias Balourdas
- School of Health Sciences, Department of Pharmacy, Division of Pharmaceutical Chemistry, National and Kapodistrian University of Athens, Panepistimiopolis-Zografou, GR-15771 Athens, Greece
| | - Vassilios Myrianthopoulos
- School of Health Sciences, Department of Pharmacy, Division of Pharmaceutical Chemistry, National and Kapodistrian University of Athens, Panepistimiopolis-Zografou, GR-15771 Athens, Greece
| | - Martin C. Taylor
- Department of Infection Biology, London School of Hygiene and Tropical Medicine, Keppel Street, London WC1E 7HT, United Kingdom
| | - Marina Šekutor
- Department of Organic Chemistry and Biochemistry, Ruder Boskovic Institute, Bijenicka cesta 54, 10 000 Zagreb, Croatia
| | - Kata Mlinarić-Majerski
- Department of Organic Chemistry and Biochemistry, Ruder Boskovic Institute, Bijenicka cesta 54, 10 000 Zagreb, Croatia
| | - John M. Kelly
- Department of Infection Biology, London School of Hygiene and Tropical Medicine, Keppel Street, London WC1E 7HT, United Kingdom
| | - Grigoris Zoidis
- School of Health Sciences, Department of Pharmacy, Division of Pharmaceutical Chemistry, National and Kapodistrian University of Athens, Panepistimiopolis-Zografou, GR-15771 Athens, Greece
| |
Collapse
|
16
|
Taylor MC, Ward A, Olmo F, Jayawardhana S, Francisco AF, Lewis MD, Kelly JM. Intracellular DNA replication and differentiation of Trypanosoma cruzi is asynchronous within individual host cells in vivo at all stages of infection. PLoS Negl Trop Dis 2020; 14:e0008007. [PMID: 32196491 PMCID: PMC7112235 DOI: 10.1371/journal.pntd.0008007] [Citation(s) in RCA: 15] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/13/2019] [Revised: 04/01/2020] [Accepted: 02/29/2020] [Indexed: 12/21/2022] Open
Abstract
Investigations into intracellular replication and differentiation of Trypanosoma cruzi within the mammalian host have been restricted by limitations in our ability to detect parasitized cells throughout the course of infection. We have overcome this problem by generating genetically modified parasites that express a bioluminescent/fluorescent fusion protein. By combining in vivo imaging and confocal microscopy, this has enabled us to routinely visualise murine infections at the level of individual host cells. These studies reveal that intracellular parasite replication is an asynchronous process, irrespective of tissue location or disease stage. Furthermore, using TUNEL assays and EdU labelling, we demonstrate that within individual infected cells, replication of both mitochondrial (kDNA) and nuclear genomes is not co-ordinated within the parasite population, and that replicating amastigotes and non-replicating trypomastigotes can co-exist in the same cell. Finally, we report the presence of distinct non-canonical morphological forms of T. cruzi in the mammalian host. These appear to represent transitional forms in the amastigote to trypomastigote differentiation process. Therefore, the intracellular life-cycle of T. cruzi in vivo is more complex than previously realised, with potential implications for our understanding of disease pathogenesis, immune evasion and drug development. Dissecting the mechanisms involved will be an important experimental challenge. Chagas disease, caused by the protozoan parasite Trypanosoma cruzi, is becoming an emerging threat in non-endemic countries and establishing new foci in endemic countries. The treatment available has not changed significantly in over 40 years. Therefore, there is an urgent need for a greater understanding of parasite biology and disease pathogenesis to identify new therapeutic targets and to maximise the efficient use of existing drugs. We have used genetically modified strains of T. cruzi carrying a bioluminescence/fluorescence dual reporter fusion gene to monitor parasite replication in vivo during both acute and chronic infections in a mouse model. Utilising TUNEL assays for mitochondrial DNA replication and EdU incorporation for total DNA replication, we have found that parasite division within infected cells is asynchronous in all phases of infection. Differentiation also appears to be uncoordinated, with replicating amastigotes co-existing with non-dividing trypomastigotes in the same host cell.
Collapse
Affiliation(s)
- Martin C. Taylor
- Faculty of Infectious and Tropical Diseases, London School of Hygiene and Tropical Medicine, London, United Kingdom
- * E-mail:
| | - Alexander Ward
- Faculty of Infectious and Tropical Diseases, London School of Hygiene and Tropical Medicine, London, United Kingdom
| | - Francisco Olmo
- Faculty of Infectious and Tropical Diseases, London School of Hygiene and Tropical Medicine, London, United Kingdom
| | - Shiromani Jayawardhana
- Faculty of Infectious and Tropical Diseases, London School of Hygiene and Tropical Medicine, London, United Kingdom
| | - Amanda F. Francisco
- Faculty of Infectious and Tropical Diseases, London School of Hygiene and Tropical Medicine, London, United Kingdom
| | - Michael D. Lewis
- Faculty of Infectious and Tropical Diseases, London School of Hygiene and Tropical Medicine, London, United Kingdom
| | - John M. Kelly
- Faculty of Infectious and Tropical Diseases, London School of Hygiene and Tropical Medicine, London, United Kingdom
| |
Collapse
|
17
|
Macleod OJS, Bart JM, MacGregor P, Peacock L, Savill NJ, Hester S, Ravel S, Sunter JD, Trevor C, Rust S, Vaughan TJ, Minter R, Mohammed S, Gibson W, Taylor MC, Higgins MK, Carrington M. A receptor for the complement regulator factor H increases transmission of trypanosomes to tsetse flies. Nat Commun 2020; 11:1326. [PMID: 32165615 PMCID: PMC7067766 DOI: 10.1038/s41467-020-15125-y] [Citation(s) in RCA: 20] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/21/2019] [Accepted: 02/15/2020] [Indexed: 11/09/2022] Open
Abstract
Persistent pathogens have evolved to avoid elimination by the mammalian immune system including mechanisms to evade complement. Infections with African trypanosomes can persist for years and cause human and animal disease throughout sub-Saharan Africa. It is not known how trypanosomes limit the action of the alternative complement pathway. Here we identify an African trypanosome receptor for mammalian factor H, a negative regulator of the alternative pathway. Structural studies show how the receptor binds ligand, leaving inhibitory domains of factor H free to inactivate complement C3b deposited on the trypanosome surface. Receptor expression is highest in developmental stages transmitted to the tsetse fly vector and those exposed to blood meals in the tsetse gut. Receptor gene deletion reduced tsetse infection, identifying this receptor as a virulence factor for transmission. This demonstrates how a pathogen evolved a molecular mechanism to increase transmission to an insect vector by exploitation of a mammalian complement regulator.
Collapse
Affiliation(s)
- Olivia J S Macleod
- Department of Biochemistry, University of Cambridge, Tennis Court Road, Cambridge, CB2 1QW, UK
| | - Jean-Mathieu Bart
- Intertryp, IRD, Cirad, University of Montpellier, Montpellier, France
| | - Paula MacGregor
- Department of Biochemistry, University of Cambridge, Tennis Court Road, Cambridge, CB2 1QW, UK
| | - Lori Peacock
- School of Biological Sciences, University of Bristol, Bristol, BS8 1UG, UK
| | - Nicholas J Savill
- Institute for Immunology and Infection Research, School of Biological Sciences, University of Edinburgh, King's Buildings, West Mains Road, Edinburgh, EH9 3JT, UK
| | - Svenja Hester
- Department of Biochemistry, University of Oxford, South Parks Road, Oxford, OX1 3QU, UK
| | - Sophie Ravel
- Intertryp, IRD, Cirad, University of Montpellier, Montpellier, France
| | - Jack D Sunter
- Department of Biological and Medical Sciences, Oxford Brookes University, Gipsy Lane, Oxford, OX3 0BP, UK
| | - Camilla Trevor
- Department of Biochemistry, University of Cambridge, Tennis Court Road, Cambridge, CB2 1QW, UK
- Department of Antibody Discovery and Protein Engineering, AstraZeneca R&D, Granta Park, Cambridge, CB21 6GH, UK
| | - Steven Rust
- Department of Antibody Discovery and Protein Engineering, AstraZeneca R&D, Granta Park, Cambridge, CB21 6GH, UK
| | - Tristan J Vaughan
- Department of Antibody Discovery and Protein Engineering, AstraZeneca R&D, Granta Park, Cambridge, CB21 6GH, UK
| | - Ralph Minter
- Department of Antibody Discovery and Protein Engineering, AstraZeneca R&D, Granta Park, Cambridge, CB21 6GH, UK
| | - Shabaz Mohammed
- Department of Biochemistry, University of Oxford, South Parks Road, Oxford, OX1 3QU, UK
| | - Wendy Gibson
- School of Biological Sciences, University of Bristol, Bristol, BS8 1UG, UK
| | - Martin C Taylor
- Faculty of Infectious and Tropical diseases, London School of Hygiene and Tropical Medicine, London, WC1E 7HT, UK
| | - Matthew K Higgins
- Department of Biochemistry, University of Oxford, South Parks Road, Oxford, OX1 3QU, UK.
| | - Mark Carrington
- Department of Biochemistry, University of Cambridge, Tennis Court Road, Cambridge, CB2 1QW, UK.
| |
Collapse
|
18
|
Georgiadis MO, Kourbeli V, Papanastasiou IP, Tsotinis A, Taylor MC, Kelly JM. Synthesis and evaluation of novel 2,4-disubstituted arylthiazoles against T. brucei. RSC Med Chem 2019; 11:72-84. [PMID: 33479605 PMCID: PMC7522794 DOI: 10.1039/c9md00478e] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/08/2019] [Accepted: 11/22/2019] [Indexed: 01/10/2023] Open
Abstract
2-{2-[3-(1-Adamantyl)-4-fluorophenyl]thiazol-4-yl}ethan-1-amine (1a) and 2-{2-[4-(1-adamantyl)phenyl]thiazol-4-yl}ethan-1-amine (2a) exhibit activity against T. brucei in the range of IC50 = 0.42 μM and IC50 = 0.80 μM, respectively.
The design, synthesis and pharmacological evaluation of the 4-substituted-2-[3-(adamant-1-yl)-4-fluorophenyl]thiazoles 1a–j, the 4-substituted-2-[4-(adamant-1-yl)phenyl]thiazoles 2a–h, the 2-substituted-4-[4-(adamant-1-yl)phenyl]thiazoles 3a–e, the N-substituted 2-phenylthiazol-4-ethylamides 4a, b and the N-substituted 4-phenylthiazol-2-ethylamides 4c, d is described. Compounds 1a and 2a exhibit trypanocidal activity in the range of IC50 = 0.42 μM and IC50 = 0.80 μM, respectively. Both of these derivatives bear a lipophilic end, which consists of a 4-(1-adamantyl) phenyl or a 3-(1-adamantyl)phenyl moiety, a 1,3-thiazole ring and a functional end, which comprises of an alkylamine and can be considered as promising candidates for the treatment of Trypanosoma brucei infections.
Collapse
Affiliation(s)
- Markos-Orestis Georgiadis
- Division of Pharmaceutical Chemistry , Department of Pharmacy , School of Health Sciences , National and Kapodistrian University of Athens , Panepistimioupoli-Zografou , 157 84 Athens , Greece .
| | - Violeta Kourbeli
- Division of Pharmaceutical Chemistry , Department of Pharmacy , School of Health Sciences , National and Kapodistrian University of Athens , Panepistimioupoli-Zografou , 157 84 Athens , Greece .
| | - Ioannis P Papanastasiou
- Division of Pharmaceutical Chemistry , Department of Pharmacy , School of Health Sciences , National and Kapodistrian University of Athens , Panepistimioupoli-Zografou , 157 84 Athens , Greece .
| | - Andrew Tsotinis
- Division of Pharmaceutical Chemistry , Department of Pharmacy , School of Health Sciences , National and Kapodistrian University of Athens , Panepistimioupoli-Zografou , 157 84 Athens , Greece .
| | - Martin C Taylor
- Department of Pathogen Molecular Biology , London School of Hygiene and Tropical Medicine , Keppel Street , London WC1 E7HT , UK
| | - John M Kelly
- Department of Pathogen Molecular Biology , London School of Hygiene and Tropical Medicine , Keppel Street , London WC1 E7HT , UK
| |
Collapse
|
19
|
Foscolos AS, Papanastasiou I, Tsotinis A, Taylor MC, Kelly JM. Synthesis and Evaluation of Nifurtimox-Adamantane Adducts with Trypanocidal Activity. ChemMedChem 2019; 14:1227-1231. [PMID: 31066972 DOI: 10.1002/cmdc.201900165] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/13/2019] [Revised: 04/11/2019] [Indexed: 11/08/2022]
Abstract
The synthesis and pharmacological evaluation of C1-substituted adamantane hydrazones, their C2-substituted isomers, and C1-substituted adamantane furanoic carboxamides is described. These new adamantane derivatives exhibited an interesting pharmacological profile in terms of trypanocidal activity and selectivity. The most active adduct with the best selectivity in this study was found to be the phenylacetoxy hydrazone 1 b (2-[4-(tricyclo[3.3.1.13,7 ]dec-1-yl)phenyl]-N'-[(5-nitrofuran-2-yl)methylene]acetohydrazide; EC50 =11±0.9 nm, SITb =770).
Collapse
Affiliation(s)
- Angeliki-Sofia Foscolos
- School of Health Sciences, Department of Pharmacy, Division of Pharmaceutical Chemistry, National and Kapodistrian University of Athens, Panepistimioupoli-Zografou, 157 84, Athens, Greece
| | - Ioannis Papanastasiou
- School of Health Sciences, Department of Pharmacy, Division of Pharmaceutical Chemistry, National and Kapodistrian University of Athens, Panepistimioupoli-Zografou, 157 84, Athens, Greece
| | - Andrew Tsotinis
- School of Health Sciences, Department of Pharmacy, Division of Pharmaceutical Chemistry, National and Kapodistrian University of Athens, Panepistimioupoli-Zografou, 157 84, Athens, Greece
| | - Martin C Taylor
- Department of Pathogen Molecular Biology, London School of Hygiene and Tropical Medicine, Keppel Street, London, WC1 E7HT, UK
| | - John M Kelly
- Department of Pathogen Molecular Biology, London School of Hygiene and Tropical Medicine, Keppel Street, London, WC1 E7HT, UK
| |
Collapse
|
20
|
MacGregor P, Gonzalez-Munoz AL, Jobe F, Taylor MC, Rust S, Sandercock AM, Macleod OJS, Van Bocxlaer K, Francisco AF, D’Hooge F, Tiberghien A, Barry CS, Howard P, Higgins MK, Vaughan TJ, Minter R, Carrington M. A single dose of antibody-drug conjugate cures a stage 1 model of African trypanosomiasis. PLoS Negl Trop Dis 2019; 13:e0007373. [PMID: 31120889 PMCID: PMC6532856 DOI: 10.1371/journal.pntd.0007373] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/14/2019] [Accepted: 04/09/2019] [Indexed: 02/02/2023] Open
Abstract
Infections of humans and livestock with African trypanosomes are treated with drugs introduced decades ago that are not always fully effective and often have severe side effects. Here, the trypanosome haptoglobin-haemoglobin receptor (HpHbR) has been exploited as a route of uptake for an antibody-drug conjugate (ADC) that is completely effective against Trypanosoma brucei in the standard mouse model of infection. Recombinant human anti-HpHbR monoclonal antibodies were isolated and shown to be internalised in a receptor-dependent manner. Antibodies were conjugated to a pyrrolobenzodiazepine (PBD) toxin and killed T. brucei in vitro at picomolar concentrations. A single therapeutic dose (0.25 mg/kg) of a HpHbR antibody-PBD conjugate completely cured a T. brucei mouse infection within 2 days with no re-emergence of infection over a subsequent time course of 77 days. These experiments provide a demonstration of how ADCs can be exploited to treat protozoal diseases that desperately require new therapeutics.
Collapse
Affiliation(s)
- Paula MacGregor
- Department of Biochemistry, University of Cambridge, Cambridge, United Kingdom
| | | | - Fatoumatta Jobe
- Department of Antibody Discovery and Protein Engineering, Medimmune, Cambridge, United Kingdom
| | - Martin C. Taylor
- London School of Hygiene and Tropical Medicine, London, United Kingdom
| | - Steven Rust
- Department of Antibody Discovery and Protein Engineering, Medimmune, Cambridge, United Kingdom
| | - Alan M. Sandercock
- Department of Antibody Discovery and Protein Engineering, Medimmune, Cambridge, United Kingdom
| | | | | | | | | | | | | | | | - Matthew K. Higgins
- Department of Biochemistry, University of Oxford, Oxford, United Kingdom
| | - Tristan J. Vaughan
- Department of Antibody Discovery and Protein Engineering, Medimmune, Cambridge, United Kingdom
| | - Ralph Minter
- Department of Antibody Discovery and Protein Engineering, Medimmune, Cambridge, United Kingdom
| | - Mark Carrington
- Department of Biochemistry, University of Cambridge, Cambridge, United Kingdom
- * E-mail:
| |
Collapse
|
21
|
Giannakopoulou E, Pardali V, Frakolaki E, Siozos V, Myrianthopoulos V, Mikros E, Taylor MC, Kelly JM, Vassilaki N, Zoidis G. Scaffold hybridization strategy towards potent hydroxamate-based inhibitors of Flaviviridae viruses and Trypanosoma species. Medchemcomm 2019; 10:991-1006. [PMID: 31303998 DOI: 10.1039/c9md00200f] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/02/2019] [Accepted: 05/15/2019] [Indexed: 12/14/2022]
Abstract
Infections with Flaviviridae viruses, such as hepatitis C virus (HCV) and dengue virus (DENV) pose global health threats. Infected individuals are at risk of developing chronic liver failure or haemorrhagic fever respectively, often with a fatal outcome if left untreated. Diseases caused by tropical parasites of the Trypanosoma species, T. brucei and T. cruzi, constitute significant socioeconomic burden in sub-Saharan Africa and continental Latin America, yet drug development is under-funded. Anti-HCV chemotherapy is associated with severe side effects and high cost, while dengue has no clinically approved therapy and antiparasitic drugs are outdated and difficult to administer. Moreover, drug resistance is an emerging concern. Consequently, the need for new revolutionary chemotherapies is urgent. By utilizing a molecular framework combination approach, we combined two distinct chemical entities with proven antiviral and trypanocidal activity into a novel hybrid scaffold attached by an acetohydroxamic acid group (CH2CONHOH), aiming at derivatives with dual activity. The novel spiro-carbocyclic substituted hydantoin analogues were rationally designed, synthesized and evaluated for their potency against three HCV genotypes (1b, 3a, 4a), DENV and two Trypanosoma species (T. brucei, T. cruzi). They exhibited significant EC50 values and remarkable selectivity indices. Several modifications were undertaken to further explore the structure activity relationships (SARs) and confirm the pivotal role of the acetohydroxamic acid metal binding group.
Collapse
Affiliation(s)
- Erofili Giannakopoulou
- School of Health Sciences , Faculty of Pharmacy , Department of Pharmaceutical Chemistry , National and Kapodistrian University of Athens , Panepistimiopolis-Zografou , GR-15771 Athens , Greece .
| | - Vasiliki Pardali
- School of Health Sciences , Faculty of Pharmacy , Department of Pharmaceutical Chemistry , National and Kapodistrian University of Athens , Panepistimiopolis-Zografou , GR-15771 Athens , Greece .
| | - Efseveia Frakolaki
- Molecular Virology Laboratory , Hellenic Pasteur Institute , Vas. Sofias Avenue , GR-11521 , Athens , Greece
| | - Vasileios Siozos
- Molecular Virology Laboratory , Hellenic Pasteur Institute , Vas. Sofias Avenue , GR-11521 , Athens , Greece
| | - Vassilios Myrianthopoulos
- School of Health Sciences , Faculty of Pharmacy , Department of Pharmaceutical Chemistry , National and Kapodistrian University of Athens , Panepistimiopolis-Zografou , GR-15771 Athens , Greece .
| | - Emmanuel Mikros
- School of Health Sciences , Faculty of Pharmacy , Department of Pharmaceutical Chemistry , National and Kapodistrian University of Athens , Panepistimiopolis-Zografou , GR-15771 Athens , Greece .
| | - Martin C Taylor
- Department of Pathogen Molecular Biology , London School of Hygiene and Tropical Medicine , Keppel Street , London WC1E 7HT , UK
| | - John M Kelly
- Department of Pathogen Molecular Biology , London School of Hygiene and Tropical Medicine , Keppel Street , London WC1E 7HT , UK
| | - Niki Vassilaki
- Molecular Virology Laboratory , Hellenic Pasteur Institute , Vas. Sofias Avenue , GR-11521 , Athens , Greece
| | - Grigoris Zoidis
- School of Health Sciences , Faculty of Pharmacy , Department of Pharmaceutical Chemistry , National and Kapodistrian University of Athens , Panepistimiopolis-Zografou , GR-15771 Athens , Greece .
| |
Collapse
|
22
|
Popov AB, Stolić I, Krstulović L, Taylor MC, Kelly JM, Tomić S, Tumir L, Bajić M, Raić-Malić S. Novel symmetric bis-benzimidazoles: Synthesis, DNA/RNA binding and antitrypanosomal activity. Eur J Med Chem 2019; 173:63-75. [PMID: 30986572 DOI: 10.1016/j.ejmech.2019.04.007] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/11/2019] [Revised: 02/22/2019] [Accepted: 04/02/2019] [Indexed: 12/11/2022]
Abstract
The novel benzimidazol-2-yl-fur-5-yl-(1,2,3)-triazolyl dimeric series with aliphatic and aromatic central linkers was successfully prepared with the aim of assessing binding affinity to DNA/RNA and antitrypanosomal activity. UV-Visible spectroscopy, thermal denaturation showed interaction of heterocyclic bis-amidines with ctDNA. Circular dichroism studies indicated uniform orientation of heterocyclic bis-amidines along the chiral double helix axis, revealing minor groove binding as the dominant binding mode. The amidino fragment and 1,4-bis(oxymethylene)phenyl spacer were the main determinants of activity against Trypanosoma brucei. The bis-benzimidazole imidazoline 15c, which had antitrypanosomal potency in the submicromolar range and DNA interacting properties, emerged as a candidate for further structural optimization to obtain more effective agents to combat trypanosome infections.
Collapse
Affiliation(s)
- A Bistrović Popov
- Department of Organic Chemistry, Faculty of Chemical Engineering and Technology, University of Zagreb, Marulićev trg 20, HR-10000, Zagreb, Croatia
| | - I Stolić
- Department of Chemistry and Biochemistry, Faculty of Veterinary Medicine, University of Zagreb, Heinzelova 55, HR-10000, Zagreb, Croatia
| | - L Krstulović
- Department of Chemistry and Biochemistry, Faculty of Veterinary Medicine, University of Zagreb, Heinzelova 55, HR-10000, Zagreb, Croatia
| | - M C Taylor
- Department of Pathogen Molecular Biology, London School of Hygiene and Tropical Medicine, Keppel Street, London, WC1E 7HT, UK
| | - J M Kelly
- Department of Pathogen Molecular Biology, London School of Hygiene and Tropical Medicine, Keppel Street, London, WC1E 7HT, UK
| | - S Tomić
- Division of Organic Chemistry and Biochemistry, Physical Chemistry, Ruđer Bošković Institute, Bijenička 54, HR-10000, Zagreb, Croatia
| | - L Tumir
- Division of Organic Chemistry and Biochemistry, Laboratory for Biomolecular Interactions and Spectroscopy, Ruđer Bošković Institute, Bijenička 54, HR-10000, Zagreb, Croatia
| | - M Bajić
- Department of Chemistry and Biochemistry, Faculty of Veterinary Medicine, University of Zagreb, Heinzelova 55, HR-10000, Zagreb, Croatia
| | - S Raić-Malić
- Department of Organic Chemistry, Faculty of Chemical Engineering and Technology, University of Zagreb, Marulićev trg 20, HR-10000, Zagreb, Croatia.
| |
Collapse
|
23
|
Georgiadis MO, Kourbeli V, Ioannidou V, Karakitsios E, Papanastasiou I, Tsotinis A, Komiotis D, Vocat A, Cole ST, Taylor MC, Kelly JM. Synthesis of diphenoxyadamantane alkylamines with pharmacological interest. Bioorg Med Chem Lett 2019; 29:1278-1281. [PMID: 30981579 DOI: 10.1016/j.bmcl.2019.04.010] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/11/2019] [Revised: 04/02/2019] [Accepted: 04/05/2019] [Indexed: 01/31/2023]
Abstract
In this work, the synthesis and the pharmacological evaluation of diphenoxyadamantane alkylamines Ia-f and IIa-f is described. The new diphenoxy-substituted adamantanes share structural features present in trypanocidal and antitubercular agents. 1-Methylpiperazine derivative Ia is the most potent against T. brucei compound, whilst its hexylamine congener IIf exhibits a significant antimycobacterial activity.
Collapse
Affiliation(s)
- Markos-Orestis Georgiadis
- School of Health Sciences, Department of Pharmacy, Division of Pharmaceutical Chemistry, National and Kapodistrian University of Athens, Panepistimioupoli-Zografou, 157 84 Athens, Greece
| | - Violeta Kourbeli
- School of Health Sciences, Department of Pharmacy, Division of Pharmaceutical Chemistry, National and Kapodistrian University of Athens, Panepistimioupoli-Zografou, 157 84 Athens, Greece
| | - Vaya Ioannidou
- School of Health Sciences, Department of Pharmacy, Division of Pharmaceutical Chemistry, National and Kapodistrian University of Athens, Panepistimioupoli-Zografou, 157 84 Athens, Greece
| | - Evangelos Karakitsios
- School of Health Sciences, Department of Pharmacy, Division of Pharmaceutical Chemistry, National and Kapodistrian University of Athens, Panepistimioupoli-Zografou, 157 84 Athens, Greece
| | - Ioannis Papanastasiou
- School of Health Sciences, Department of Pharmacy, Division of Pharmaceutical Chemistry, National and Kapodistrian University of Athens, Panepistimioupoli-Zografou, 157 84 Athens, Greece.
| | - Andrew Tsotinis
- School of Health Sciences, Department of Pharmacy, Division of Pharmaceutical Chemistry, National and Kapodistrian University of Athens, Panepistimioupoli-Zografou, 157 84 Athens, Greece
| | - Dimitri Komiotis
- Department of Biochemistry and Biotechnology, Laboratory of Bioorganic Chemistry, University of Thessaly, 41221 Larissa, Greece
| | - Anthony Vocat
- Global Health Institute, École Polytechnique Fédérale de Lausanne, Station 19, 1015 Lausanne, Switzerland
| | - Stewart T Cole
- Global Health Institute, École Polytechnique Fédérale de Lausanne, Station 19, 1015 Lausanne, Switzerland; Institut Pasteur, 25-28 rue du Docteur Roux, 75724 Paris Cedex 15, France
| | - Martin C Taylor
- Department of Pathogen Molecular Biology, London School of Hygiene and Tropical Medicine, Keppel Street, London WC1 E7HT, UK
| | - John M Kelly
- Department of Pathogen Molecular Biology, London School of Hygiene and Tropical Medicine, Keppel Street, London WC1 E7HT, UK
| |
Collapse
|
24
|
Karpe AV, Dunn MS, Taylor MC, Nguyen T, Ong C, Karla T, Rockman S, Beale DJ. Nitrogen deprivation in Fusarium oxysporum promotes mycotoxin production via intermediates in the Krebs cycle and unreported methylmalonyl-CoA mutase activity. Metabolomics 2018; 14:160. [PMID: 30830469 DOI: 10.1007/s11306-018-1459-0] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 10/31/2018] [Accepted: 12/05/2018] [Indexed: 12/28/2022]
Abstract
INTRODUCTION Fusarium oxysporum has a high affinity for lignin and cellulose-based substrates and is known to grow in a wide range of environments. It is these properties and its ability to produce mycotoxins that have contributed to its pathogenicity in cereal crops that can affect human and animal health when ingested. OBJECTIVES Identify the mechanisms of mycotoxin production and map the functional output of F. oxysporum under varying growth conditions. METHODS Liquid and gas-based chromatography coupled with mass spectrometry was used to identify and map the untargeted metabolic pathway of F. oxysporum grown using nitrogen limited and organic/inorganic nitrogen supplemented media. RESULTS Over 1300 metabolites were identified, relating to 42 metabolic pathways. Of these, 520 metabolites merged at pyruvate (glycolysis), succinate (Krebs cycle) and aspartate-glutamate metabolic pathways. CoA depletion at the growth stage triggered the initiation of fatty acid and branched amino acid degradation. This in turn activated propionyl CoA carnitine acetyltransferase enzymes, resulting in nitrogen preservation (urea, putrescine and organic acids end-products). CoA then transferred into the TCA cycle via previously unreported β-alanine and propionyl CoA metabolic pathways, the latter likely being a novel methylmalonyl-CoA mutase activity for F. oxysporum. CONCLUSIONS The lower supplementation of inorganic nitrogen compounds (≤ 50 mM) and the elimination of nitrates/organic nitrogen sources resulted in TCA autophagy events that boosted mycotoxin-based metabolism and decreased overall F. oxysporum growth. Such knowledge of functional mycotoxin production can be used to supplement agricultural crops and reduce the risk of mycotoxin contamination in human and animal food supplies.
Collapse
Affiliation(s)
- A V Karpe
- Land & Water, CSIRO, Ecosciences Precinct, Dutton Park, QLD, 4102, Australia
| | - M S Dunn
- Technical Development, Seqirus, 63 Poplar Road, Parkville, VIC, 3052, Australia
| | - M C Taylor
- Land & Water, CSIRO, Acton, ACT, 2601, Australia
| | - T Nguyen
- Technical Development, Seqirus, 63 Poplar Road, Parkville, VIC, 3052, Australia
| | - C Ong
- Technical Development, Seqirus, 63 Poplar Road, Parkville, VIC, 3052, Australia
| | - T Karla
- Technical Development, Seqirus, 63 Poplar Road, Parkville, VIC, 3052, Australia
| | - S Rockman
- Technical Development, Seqirus, 63 Poplar Road, Parkville, VIC, 3052, Australia
| | - D J Beale
- Land & Water, CSIRO, Ecosciences Precinct, Dutton Park, QLD, 4102, Australia.
| |
Collapse
|
25
|
Bistrović A, Krstulović L, Stolić I, Drenjančević D, Talapko J, Taylor MC, Kelly JM, Bajić M, Raić-Malić S. Synthesis, anti-bacterial and anti-protozoal activities of amidinobenzimidazole derivatives and their interactions with DNA and RNA. J Enzyme Inhib Med Chem 2018; 33:1323-1334. [PMID: 30165753 PMCID: PMC6127852 DOI: 10.1080/14756366.2018.1484733] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/25/2018] [Revised: 05/18/2018] [Accepted: 05/31/2018] [Indexed: 02/09/2023] Open
Abstract
Amidinobenzimidazole derivatives connected to 1-aryl-substituted 1,2,3-triazole through phenoxymethylene linkers 7a-7e, 8a-8e, and 9a-9e were designed and synthesised with the aim of evaluating their anti-bacterial and anti-trypanosomal activities and DNA/RNA binding affinity. Results from anti-bacterial evaluations of antibiotic-resistant pathogenic bacteria revealed that both o-chlorophenyl-1,2,3-triazole and N-isopropylamidine moieties in 8c led to strong inhibitory activity against resistant Gram-positive bacteria, particularly the MRSA strain. Furthermore, the non-substituted amidine and phenyl ring in 7a induced a marked anti-bacterial effect, with potency against ESBL-producing Gram-negative E. coli better than those of the antibiotics ceftazidime and ciprofloxacin. UV-Vis and CD spectroscopy, as well as thermal denaturation assays, indicated that compounds 7a and 8c showed also binding affinities towards ctDNA. Anti-trypanosomal evaluations showed that the p-methoxyphenyl-1,2,3-triazole moiety in 7b and 9b enhanced inhibitory activity against T. brucei, with 8b being more potent than nifurtimox, and having minimal toxicity towards mammalian cells.
Collapse
Affiliation(s)
- Andrea Bistrović
- Department of Organic Chemistry, Faculty of Chemical Engineering and Technology, University of Zagreb, Zagreb, Croatia
| | - Luka Krstulović
- Department of Chemistry and Biochemistry, Faculty of Veterinary Medicine, University of Zagreb, Zagreb, Croatia
| | - Ivana Stolić
- Department of Chemistry and Biochemistry, Faculty of Veterinary Medicine, University of Zagreb, Zagreb, Croatia
| | - Domagoj Drenjančević
- Department of Transfusion Medicine, Osijek University Hospital, Osijek, Croatia
- Department of Microbiology and Parasitology, Faculty of Medicine, University of Osijek, Osijek, Croatia
| | - Jasminka Talapko
- Department of Microbiology and Parasitology, Faculty of Medicine, University of Osijek, Osijek, Croatia
| | - Martin C. Taylor
- Department of Pathogen Molecular Biology, London School of Hygiene and Tropical Medicine, London, UK
| | - John M. Kelly
- Department of Pathogen Molecular Biology, London School of Hygiene and Tropical Medicine, London, UK
| | - Miroslav Bajić
- Department of Chemistry and Biochemistry, Faculty of Veterinary Medicine, University of Zagreb, Zagreb, Croatia
| | - Silvana Raić-Malić
- Department of Organic Chemistry, Faculty of Chemical Engineering and Technology, University of Zagreb, Zagreb, Croatia
| |
Collapse
|
26
|
|
27
|
Dahal LN, Huang CY, Stopforth RJ, Mead A, Chan K, Bowater JX, Taylor MC, Narang P, Chan HTC, Kim JH, Vaughan AT, Forconi F, Beers SA. Shaving Is an Epiphenomenon of Type I and II Anti-CD20-Mediated Phagocytosis, whereas Antigenic Modulation Limits Type I Monoclonal Antibody Efficacy. J Immunol 2018; 201:1211-1221. [PMID: 29997125 PMCID: PMC6082343 DOI: 10.4049/jimmunol.1701122] [Citation(s) in RCA: 13] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/07/2017] [Accepted: 06/10/2018] [Indexed: 01/09/2023]
Abstract
Rituximab is an anti-CD20 mAb used in the treatment of B cell malignancies. Loss of surface CD20 Ag from the surface of target cells is thought to be one mechanism governing resistance to rituximab, but how this occurs is not completely understood. Two explanations for this have been proposed: antigenic modulation whereby mAb:CD20 complexes are internalized in a B cell intrinsic process and shaving, in which mAb:CD20 complexes undergo trogocytic removal by effector cells, such as macrophages. However, there is conflicting evidence as to which predominates in clinical scenarios and hence the best strategies to overcome resistance. In this study, we investigated the relative importance of modulation and shaving in the downregulation of surface mAb:CD20. We used both murine and human systems and treated ex vivo macrophages with varying concentrations of non-FcγR-interacting beads to achieve differential macrophage saturation states, hence controllably suppressing further phagocytosis of target cells. We then monitored the level and localization of mAb:CD20 using a quenching assay. Suppression of phagocytosis with bead treatment decreased shaving and increased modulation, suggesting that the two compete for surface rituximab:CD20. Under all conditions tested, modulation predominated in rituximab loss, whereas shaving represented an epiphenomenon to phagocytosis. We also demonstrate that the nonmodulating, glycoengineered, type II mAb obinutuzumab caused a modest but significant increase in shaving compared with type II BHH2 human IgG1 wild-type mAb. Therefore, shaving may represent an important mechanism of resistance when modulation is curtailed, and glycoengineering mAb to increase affinity for FcγR may enhance resistance because of shaving.
Collapse
Affiliation(s)
- Lekh N Dahal
- Antibody and Vaccine Group, Centre for Cancer Immunology, Faculty of Medicine, University of Southampton, Southampton General Hospital, Southampton SO16 6YD, United Kingdom; and
| | - Chie-Yin Huang
- Antibody and Vaccine Group, Centre for Cancer Immunology, Faculty of Medicine, University of Southampton, Southampton General Hospital, Southampton SO16 6YD, United Kingdom; and
| | - Richard J Stopforth
- Antibody and Vaccine Group, Centre for Cancer Immunology, Faculty of Medicine, University of Southampton, Southampton General Hospital, Southampton SO16 6YD, United Kingdom; and
| | - Abbie Mead
- Antibody and Vaccine Group, Centre for Cancer Immunology, Faculty of Medicine, University of Southampton, Southampton General Hospital, Southampton SO16 6YD, United Kingdom; and
| | - Keith Chan
- Antibody and Vaccine Group, Centre for Cancer Immunology, Faculty of Medicine, University of Southampton, Southampton General Hospital, Southampton SO16 6YD, United Kingdom; and
| | - Juliet X Bowater
- Antibody and Vaccine Group, Centre for Cancer Immunology, Faculty of Medicine, University of Southampton, Southampton General Hospital, Southampton SO16 6YD, United Kingdom; and
| | - Martin C Taylor
- Antibody and Vaccine Group, Centre for Cancer Immunology, Faculty of Medicine, University of Southampton, Southampton General Hospital, Southampton SO16 6YD, United Kingdom; and
| | - Priyanka Narang
- Antibody and Vaccine Group, Centre for Cancer Immunology, Faculty of Medicine, University of Southampton, Southampton General Hospital, Southampton SO16 6YD, United Kingdom; and
| | - H T Claude Chan
- Antibody and Vaccine Group, Centre for Cancer Immunology, Faculty of Medicine, University of Southampton, Southampton General Hospital, Southampton SO16 6YD, United Kingdom; and
| | - Jinny H Kim
- Antibody and Vaccine Group, Centre for Cancer Immunology, Faculty of Medicine, University of Southampton, Southampton General Hospital, Southampton SO16 6YD, United Kingdom; and
| | - Andrew T Vaughan
- Antibody and Vaccine Group, Centre for Cancer Immunology, Faculty of Medicine, University of Southampton, Southampton General Hospital, Southampton SO16 6YD, United Kingdom; and
| | - Francesco Forconi
- Cancer Sciences Unit, Cancer Research UK and National Institute for Health Research Experimental Cancer Medicine Centres, University of Southampton, Southampton General Hospital, Southampton SO16 6YD, United Kingdom
| | - Stephen A Beers
- Antibody and Vaccine Group, Centre for Cancer Immunology, Faculty of Medicine, University of Southampton, Southampton General Hospital, Southampton SO16 6YD, United Kingdom; and
| |
Collapse
|
28
|
Lewis MD, Francisco AF, Jayawardhana S, Langston H, Taylor MC, Kelly JM. Imaging the development of chronic Chagas disease after oral transmission. Sci Rep 2018; 8:11292. [PMID: 30050153 PMCID: PMC6062536 DOI: 10.1038/s41598-018-29564-7] [Citation(s) in RCA: 29] [Impact Index Per Article: 4.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/05/2018] [Accepted: 07/10/2018] [Indexed: 12/26/2022] Open
Abstract
Chagas disease is a zoonosis caused by the protozoan parasite Trypanosoma cruzi. Transmission cycles are maintained by haematophagous triatomine bug vectors that carry infective T. cruzi in their faeces. Most human infections are acquired by contamination of mucosal membranes with triatomine faeces after being bitten, however, T. cruzi can be transmitted by several other routes. Oral transmission is an increasingly important aspect of Chagas disease epidemiology, typically involving food or drink products contaminated with triatomines. This has recently caused numerous outbreaks and been linked to unusually severe acute infections. The long-term impact of oral transmission on infection dynamics and disease pathogenesis is unclear. We used highly sensitive bioluminescence imaging and quantitative histopathology to study orally transmitted T. cruzi infections in mice. Both metacyclic and bloodform trypomastigotes were infectious via the oral cavity, but only metacyclics led to established infections by intra-gastric gavage. Mice displayed only mild acute symptoms but later developed significantly increased myocardial collagen content (p = 0.017), indicative of fibrosis. Gastrointestinal tissues and skin were the principal chronic infection reservoirs. Chronic phase parasite load profiles, tissue distribution and myocardial fibrosis severity were comparable to needle-injected controls. Thus, the oral route neither exacerbates nor ameliorates experimental Chagas disease.
Collapse
Affiliation(s)
- Michael D Lewis
- Department of Pathogen Molecular Biology, Faculty of Infectious and Tropical Diseases, London School of Hygiene and Tropical Medicine, Keppel Street, London, WC1E 7HT, United Kingdom.
| | - Amanda F Francisco
- Department of Pathogen Molecular Biology, Faculty of Infectious and Tropical Diseases, London School of Hygiene and Tropical Medicine, Keppel Street, London, WC1E 7HT, United Kingdom
| | - Shiromani Jayawardhana
- Department of Pathogen Molecular Biology, Faculty of Infectious and Tropical Diseases, London School of Hygiene and Tropical Medicine, Keppel Street, London, WC1E 7HT, United Kingdom
| | - Harry Langston
- Department of Pathogen Molecular Biology, Faculty of Infectious and Tropical Diseases, London School of Hygiene and Tropical Medicine, Keppel Street, London, WC1E 7HT, United Kingdom
| | - Martin C Taylor
- Department of Pathogen Molecular Biology, Faculty of Infectious and Tropical Diseases, London School of Hygiene and Tropical Medicine, Keppel Street, London, WC1E 7HT, United Kingdom
| | - John M Kelly
- Department of Pathogen Molecular Biology, Faculty of Infectious and Tropical Diseases, London School of Hygiene and Tropical Medicine, Keppel Street, London, WC1E 7HT, United Kingdom
| |
Collapse
|
29
|
Olmo F, Costa FC, Mann GS, Taylor MC, Kelly JM. Optimising genetic transformation of Trypanosoma cruzi using hydroxyurea-induced cell-cycle synchronisation. Mol Biochem Parasitol 2018; 226:34-36. [PMID: 29990513 PMCID: PMC6254250 DOI: 10.1016/j.molbiopara.2018.07.002] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/15/2018] [Revised: 06/27/2018] [Accepted: 07/04/2018] [Indexed: 11/29/2022]
Abstract
A straightforward method for optimising Trypanosoma cruzi transfection efficiency. Facilitated by hydroxyurea-induced cell-cycle synchronization. Applicable to both episomal and integrative-mediated transformation. Reduces the time required to generate genetically modified cell lines. Increases the number of stably transformed clones.
The limited flexibility and time-consuming nature of the genetic manipulation procedures applicable to Trypanosoma cruzi continue to restrict the functional dissection of this parasite. We hypothesised that transformation efficiency could be enhanced if electroporation was timed to coincide with DNA replication. To test this, we generated epimastigote cultures enriched at the G1/S boundary using hydroxyurea-induced cell-cycle synchronisation, and then electroporated parasites at various time points after release from the cell-cycle block. We found a significant increase in transformation efficiency, with both episomal and integrative constructs, when cultures were electroporated 1 h after hydroxyurea removal. It was possible to generate genetically modified populations in less than 2 weeks, compared to the normal 4–6 weeks, with a 5 to 8-fold increase in the number of stably transformed clones. This straightforward optimisation step can be widely applied and should help streamline functional studies in T. cruzi.
Collapse
Affiliation(s)
- Francisco Olmo
- Department of Pathogen Molecular Biology, London School of Hygiene and Tropical Medicine, Keppel Street, London, WC1E 7HT, UK.
| | - Fernanda C Costa
- Department of Pathogen Molecular Biology, London School of Hygiene and Tropical Medicine, Keppel Street, London, WC1E 7HT, UK; Institute of Physics of São Carlos, University of São Paulo, São Carlos, 13563-120, Brazil.
| | - Gurdip Singh Mann
- Department of Pathogen Molecular Biology, London School of Hygiene and Tropical Medicine, Keppel Street, London, WC1E 7HT, UK.
| | - Martin C Taylor
- Department of Pathogen Molecular Biology, London School of Hygiene and Tropical Medicine, Keppel Street, London, WC1E 7HT, UK.
| | - John M Kelly
- Department of Pathogen Molecular Biology, London School of Hygiene and Tropical Medicine, Keppel Street, London, WC1E 7HT, UK.
| |
Collapse
|
30
|
Artigas A, Sola I, Taylor MC, Clos MV, Perez B, Kelly JM, Munoz-Torrero D. Synthesis and Biological Evaluation of Heteroarylnonanenitriles as Potential Antitrypanosomal Agents: Serendipitous Discovery of Novel Anticholinesterase Hits. LETT ORG CHEM 2018. [DOI: 10.2174/1570178615666171219164459] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022]
Affiliation(s)
- Albert Artigas
- Laboratory of Pharmaceutical Chemistry (CSIC Associated Unit), Faculty of Pharmacy and Food Sciences, and Institute of Biomedicine (IBUB), University of Barcelona, Barcelona, Spain
| | - Irene Sola
- Laboratory of Pharmaceutical Chemistry (CSIC Associated Unit), Faculty of Pharmacy and Food Sciences, and Institute of Biomedicine (IBUB), University of Barcelona, Barcelona, Spain
| | - Martin C. Taylor
- Department of Pathogen Molecular Biology, London School of Hygiene and Tropical Medicine, London, United Kingdom
| | - M. Victoria Clos
- Department of Pharmacology, Therapeutics and Toxicology, Institute of Neurosciences, Autonomous University of Barcelona, Bellaterra, Barcelona, Spain
| | - Belen Perez
- Department of Pharmacology, Therapeutics and Toxicology, Institute of Neurosciences, Autonomous University of Barcelona, Bellaterra, Barcelona, Spain
| | - John M. Kelly
- Department of Pathogen Molecular Biology, London School of Hygiene and Tropical Medicine, London, United Kingdom
| | - Diego Munoz-Torrero
- Laboratory of Pharmaceutical Chemistry (CSIC Associated Unit), Faculty of Pharmacy and Food Sciences, and Institute of Biomedicine (IBUB), University of Barcelona, Barcelona, Spain
| |
Collapse
|
31
|
Zoidis G, Tsotinis A, Tsatsaroni A, Taylor MC, Kelly JM, Efstathiou A, Smirlis D, Fytas G. Lipophilic conformationally constrained spiro carbocyclic 2,6-diketopiperazine-1-acetohydroxamic acid analogues as trypanocidal and leishmanicidal agents: An extended SAR study. Chem Biol Drug Des 2017; 91:408-421. [PMID: 28834291 DOI: 10.1111/cbdd.13088] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/12/2017] [Revised: 07/18/2017] [Accepted: 08/09/2017] [Indexed: 01/13/2023]
Abstract
We have previously described a number of lipophilic conformationally constrained spiro carbocyclic 2,6-diketopiperazine (2,6-DKP)-1-acetohydroxamic acids as potent antitrypanosomal agents. In this report, we extend the SAR analysis in this class of compounds with respect to in vitro growth inhibition of Trypanosoma and Leishmania parasites. Introduction of bulky hydrophobic substituents at the vicinal position of the basic nitrogen atom in the spiro carbocyclic 2,6-DKP ring system can provide analogues which are potently active against bloodstream form Trypanosoma brucei and exhibit significant activities toward Trypanosoma cruzi epimastogotes and Leishmania infantum promastigotes and intracellular amastigotes. In particular, compounds possessing a benzyl or 4-chlorobenzyl substituent were found to be the most active growth inhibitors, with activities in the low nanomolar and low micromolar ranges for T. brucei and L. infantum, respectively. The benzyl-substituted (S)-enantiomer was the most potent derivative against T. brucei (IC50 = 6.8 nm), T. cruzi (IC50 = 0.21 μm), and L. infantum promastigotes (IC50 = 2.67 μm) and intracellular amastigotes (IC50 = 2.60 μm). Moreover, the (R)-chiral benzyl-substituted derivative and its racemic counterpart displayed significant activities against L. donovani. Importantly, the active compounds show high selectivity in comparison with two mammalian cell lines.
Collapse
Affiliation(s)
- Grigoris Zoidis
- Department of Pharmaceutical Chemistry, Faculty of Pharmacy, School of Health Sciences, National and Kapodistrian University of Athens, Athens, Greece
| | - Andrew Tsotinis
- Department of Pharmaceutical Chemistry, Faculty of Pharmacy, School of Health Sciences, National and Kapodistrian University of Athens, Athens, Greece
| | - Alexandra Tsatsaroni
- Department of Pharmaceutical Chemistry, Faculty of Pharmacy, School of Health Sciences, National and Kapodistrian University of Athens, Athens, Greece
| | - Martin C Taylor
- Department of Pathogen Molecular Biology, London School of Hygiene and Tropical Medicine, London, UK
| | - John M Kelly
- Department of Pathogen Molecular Biology, London School of Hygiene and Tropical Medicine, London, UK
| | - Antonia Efstathiou
- Laboratory of Molecular Parasitology, Department of Microbiology, Hellenic Pasteur Institute, Athens, Greece
| | - Despina Smirlis
- Laboratory of Molecular Parasitology, Department of Microbiology, Hellenic Pasteur Institute, Athens, Greece
| | - George Fytas
- Department of Pharmaceutical Chemistry, Faculty of Pharmacy, School of Health Sciences, National and Kapodistrian University of Athens, Athens, Greece
| |
Collapse
|
32
|
Geoghegan PH, Laffra AM, Hoogendorp NK, Taylor MC, Jermy MC. Experimental measurement of breath exit velocity and expirated bloodstain patterns produced under different exhalation mechanisms. Int J Legal Med 2017; 131:1193-1201. [PMID: 28154922 DOI: 10.1007/s00414-017-1545-2] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/06/2016] [Accepted: 01/19/2017] [Indexed: 11/24/2022]
Abstract
In an attempt to obtain a deeper understanding of the factors which determine the characteristics of expirated bloodstain patterns, the mechanism of formation of airborne droplets was studied. Hot wire anemometry measured air velocity, 25 mm from the lips, for 31 individuals spitting, coughing and blowing. Expirated stains were produced by the same mechanisms performed by one individual with different volumes of a synthetic blood substitute in their mouth. The atomization of the liquid at the lips was captured with high-speed video, and the resulting stain patterns were captured on paper targets. Peak air velocities varied for blowing (6 to 64 m/s), spitting (1 to 64 m/s) and coughing (1 to 47 m/s), with mean values of 12 m/s (blowing), 7 m/s (spitting) and 4 m/s (coughing). There was a large (55-65%) variation between individuals in air velocity produced, as well as variation between trials for a single individual (25-35%). Spitting and blowing involved similar lip shapes. Blowing had a longer duration of airflow, though it is not the duration but the peak velocity at the beginning of the air motion which appears to control the atomization of blood in the mouth and thus stain formation. Spitting could project quantities of drops at least 1600 mm. Coughing had a shorter range of near 500 mm, with a few droplets travelling further. All mechanisms could spread drops over an angle >45°. Spitting was the most effective for projecting drops of blood from the mouth, due to its combination of chest motion and mouth shape producing strong air velocities. No unique method was found of inferring the physical action (spitting, coughing or blowing) from characteristics of the pattern, except possibly distance travelled. Diameter range in expirated bloodstains varied from very small (<1 mm) in a dense formation to several millimetres. No unique method was found of discriminating expirated patterns from gunshot or impact patterns on stain shape alone. Only 20% of the expirated patterns produced in this study contained identifiable bubble rings or beaded stains.
Collapse
Affiliation(s)
- P H Geoghegan
- Department of Mechanical Engineering, University of Canterbury, Private Bag 4800, Christchurch, Canterbury, 8041, New Zealand.
| | - A M Laffra
- University of Applied Sciences Van Hall Larenstein, Leeuwarden, 8934 CJ, The Netherlands
| | - N K Hoogendorp
- University of Applied Sciences Van Hall Larenstein, Leeuwarden, 8934 CJ, The Netherlands
| | - M C Taylor
- Christchurch Science Centre, Institute of Environmental Science and Research (ESR), 27 Creyke Road, Christchurch, Canterbury, 8041, New Zealand
| | - M C Jermy
- Department of Mechanical Engineering, University of Canterbury, Private Bag 4800, Christchurch, Canterbury, 8041, New Zealand
| |
Collapse
|
33
|
Lewis MD, Francisco AF, Taylor MC, Jayawardhana S, Kelly JM. Host and parasite genetics shape a link between Trypanosoma cruzi infection dynamics and chronic cardiomyopathy. Cell Microbiol 2016; 18:1429-43. [PMID: 26918803 PMCID: PMC5031194 DOI: 10.1111/cmi.12584] [Citation(s) in RCA: 60] [Impact Index Per Article: 7.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/14/2015] [Accepted: 02/21/2016] [Indexed: 12/15/2022]
Abstract
Host and parasite diversity are suspected to be key factors in Chagas disease pathogenesis. Experimental investigation of underlying mechanisms is hampered by a lack of tools to detect scarce, pleiotropic infection foci. We developed sensitive imaging models to track Trypanosoma cruzi infection dynamics and quantify tissue-specific parasite loads, with minimal sampling bias. We used this technology to investigate cardiomyopathy caused by highly divergent parasite strains in BALB/c, C3H/HeN and C57BL/6 mice. The gastrointestinal tract was unexpectedly found to be the primary site of chronic infection in all models. Immunosuppression induced expansion of parasite loads in the gut and was followed by widespread dissemination. These data indicate that differential immune control of T. cruzi occurs between tissues and shows that the large intestine and stomach provide permissive niches for active infection. The end-point frequency of heart-specific infections ranged from 0% in TcVI-CLBR-infected C57BL/6 to 88% in TcI-JR-infected C3H/HeN mice. Nevertheless, infection led to fibrotic cardiac pathology in all models. Heart disease severity was associated with the model-dependent frequency of dissemination outside the gut and inferred cumulative heart-specific parasite loads. We propose a model of cardiac pathogenesis driven by periodic trafficking of parasites into the heart, occurring at a frequency determined by host and parasite genetics.
Collapse
Affiliation(s)
- Michael D Lewis
- Department of Pathogen Molecular Biology, London School of Hygiene and Tropical Medicine, Keppel Street, London, WC1E 7HT, UK.
- Laboratory of Parasitic Diseases, National Institute of Allergy and Infectious Diseases, Bethesda, Maryland, 20892, USA.
| | - Amanda Fortes Francisco
- Department of Pathogen Molecular Biology, London School of Hygiene and Tropical Medicine, Keppel Street, London, WC1E 7HT, UK
| | - Martin C Taylor
- Department of Pathogen Molecular Biology, London School of Hygiene and Tropical Medicine, Keppel Street, London, WC1E 7HT, UK
| | - Shiromani Jayawardhana
- Department of Pathogen Molecular Biology, London School of Hygiene and Tropical Medicine, Keppel Street, London, WC1E 7HT, UK
| | - John M Kelly
- Department of Pathogen Molecular Biology, London School of Hygiene and Tropical Medicine, Keppel Street, London, WC1E 7HT, UK
| |
Collapse
|
34
|
Sola I, Artigas A, Taylor MC, Pérez-Areales FJ, Viayna E, Clos MV, Pérez B, Wright CW, Kelly JM, Muñoz-Torrero D. Synthesis and biological evaluation of N-cyanoalkyl-, N-aminoalkyl-, and N-guanidinoalkyl-substituted 4-aminoquinoline derivatives as potent, selective, brain permeable antitrypanosomal agents. Bioorg Med Chem 2016; 24:5162-5171. [PMID: 27591008 PMCID: PMC5080452 DOI: 10.1016/j.bmc.2016.08.036] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/13/2016] [Revised: 08/19/2016] [Accepted: 08/20/2016] [Indexed: 11/30/2022]
Abstract
Current drugs against human African trypanosomiasis (HAT) suffer from several serious drawbacks. The search for novel, effective, brain permeable, safe, and inexpensive antitrypanosomal compounds is therefore an urgent need. We have recently reported that the 4-aminoquinoline derivative huprine Y, developed in our group as an anticholinesterasic agent, exhibits a submicromolar potency against Trypanosoma brucei and that its homo- and hetero-dimerization can result in to up to three-fold increased potency and selectivity. As an alternative strategy towards more potent smaller molecule anti-HAT agents, we have explored the introduction of ω-cyanoalkyl, ω-aminoalkyl, or ω-guanidinoalkyl chains at the primary amino group of huprine or the simplified 4-aminoquinoline analogue tacrine. Here, we describe the evaluation of a small in-house library and a second generation of newly synthesized derivatives, which has led to the identification of 13 side chain modified 4-aminoquinoline derivatives with submicromolar potencies against T. brucei. Among these compounds, the guanidinononyltacrine analogue 15e exhibits a 5-fold increased antitrypanosomal potency, 10-fold increased selectivity, and 100-fold decreased anticholinesterasic activity relative to the parent huprine Y. Its biological profile, lower molecular weight relative to dimeric compounds, reduced lipophilicity, and ease of synthesis, make it an interesting anti-HAT lead, amenable to further optimization to eliminate its remaining anticholinesterasic activity.
Collapse
Affiliation(s)
- Irene Sola
- Laboratory of Pharmaceutical Chemistry (CSIC Associated Unit), Faculty of Pharmacy and Food Sciences, and Institute of Biomedicine (IBUB), University of Barcelona, Av. Joan XXIII, 27-31, E-08028 Barcelona, Spain
| | - Albert Artigas
- Laboratory of Pharmaceutical Chemistry (CSIC Associated Unit), Faculty of Pharmacy and Food Sciences, and Institute of Biomedicine (IBUB), University of Barcelona, Av. Joan XXIII, 27-31, E-08028 Barcelona, Spain
| | - Martin C Taylor
- Department of Pathogen Molecular Biology, London School of Hygiene and Tropical Medicine, Keppel Street, London WC1E 7HT, United Kingdom
| | - F Javier Pérez-Areales
- Laboratory of Pharmaceutical Chemistry (CSIC Associated Unit), Faculty of Pharmacy and Food Sciences, and Institute of Biomedicine (IBUB), University of Barcelona, Av. Joan XXIII, 27-31, E-08028 Barcelona, Spain
| | - Elisabet Viayna
- Laboratory of Pharmaceutical Chemistry (CSIC Associated Unit), Faculty of Pharmacy and Food Sciences, and Institute of Biomedicine (IBUB), University of Barcelona, Av. Joan XXIII, 27-31, E-08028 Barcelona, Spain
| | - M Victòria Clos
- Department of Pharmacology, Therapeutics and Toxicology, Institute of Neurosciences, Autonomous University of Barcelona, E-08193, Bellaterra, Barcelona, Spain
| | - Belén Pérez
- Department of Pharmacology, Therapeutics and Toxicology, Institute of Neurosciences, Autonomous University of Barcelona, E-08193, Bellaterra, Barcelona, Spain
| | - Colin W Wright
- Bradford School of Pharmacy, University of Bradford, West Yorkshire BD7 1 DP, United Kingdom
| | - John M Kelly
- Department of Pathogen Molecular Biology, London School of Hygiene and Tropical Medicine, Keppel Street, London WC1E 7HT, United Kingdom
| | - Diego Muñoz-Torrero
- Laboratory of Pharmaceutical Chemistry (CSIC Associated Unit), Faculty of Pharmacy and Food Sciences, and Institute of Biomedicine (IBUB), University of Barcelona, Av. Joan XXIII, 27-31, E-08028 Barcelona, Spain.
| |
Collapse
|
35
|
Foscolos AS, Papanastasiou I, Foscolos GB, Tsotinis A, Kellici TF, Mavromoustakos T, Taylor MC, Kelly JM. New hydrazones of 5-nitro-2-furaldehyde with adamantanealkanohydrazides: synthesis and in vitro trypanocidal activity. Med Chem Commun 2016. [DOI: 10.1039/c6md00035e] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
Abstract
A range of hydrazones of 5-nitro-2-furaldehyde with adamantane alkanohydrazides was synthesized and their trypanocidal activity was evaluated.
Collapse
Affiliation(s)
- Angeliki-Sofia Foscolos
- School of Health Sciences
- Faculty of Pharmacy
- Department of Pharmaceutical Chemistry
- National and Kapodistrian University of Athens
- 15784 Athens
| | - Ioannis Papanastasiou
- School of Health Sciences
- Faculty of Pharmacy
- Department of Pharmaceutical Chemistry
- National and Kapodistrian University of Athens
- 15784 Athens
| | - George B. Foscolos
- School of Health Sciences
- Faculty of Pharmacy
- Department of Pharmaceutical Chemistry
- National and Kapodistrian University of Athens
- 15784 Athens
| | - Andrew Tsotinis
- School of Health Sciences
- Faculty of Pharmacy
- Department of Pharmaceutical Chemistry
- National and Kapodistrian University of Athens
- 15784 Athens
| | - Tahsin F. Kellici
- Faculty of Chemistry
- Department of Organic Chemistry
- University of Athens
- 15771 Athens
- Greece
| | - Thomas Mavromoustakos
- Faculty of Chemistry
- Department of Organic Chemistry
- University of Athens
- 15771 Athens
- Greece
| | - Martin C. Taylor
- Department of Pathogen Molecular Biology
- London School of Hygiene and Tropical Medicine
- London WC1 E7HT
- UK
| | - John M. Kelly
- Department of Pathogen Molecular Biology
- London School of Hygiene and Tropical Medicine
- London WC1 E7HT
- UK
| |
Collapse
|
36
|
Di Pietro O, Vicente-García E, Taylor MC, Berenguer D, Viayna E, Lanzoni A, Sola I, Sayago H, Riera C, Fisa R, Clos MV, Pérez B, Kelly JM, Lavilla R, Muñoz-Torrero D. Multicomponent reaction-based synthesis and biological evaluation of tricyclic heterofused quinolines with multi-trypanosomatid activity. Eur J Med Chem 2015; 105:120-37. [PMID: 26479031 PMCID: PMC4638191 DOI: 10.1016/j.ejmech.2015.10.007] [Citation(s) in RCA: 49] [Impact Index Per Article: 5.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/12/2015] [Revised: 09/28/2015] [Accepted: 10/06/2015] [Indexed: 11/28/2022]
Abstract
Human African trypanosomiasis (HAT), Chagas disease and leishmaniasis, which are caused by the trypanosomatids Trypanosoma brucei, Trypanosoma cruzi and Leishmania species, are among the most deadly neglected tropical diseases. The development of drugs that are active against several trypanosomatids is appealing from a clinical and economic viewpoint, and seems feasible, as these parasites share metabolic pathways and hence might be treatable by common drugs. From benzonapthyridine 1, an inhibitor of acetylcholinesterase (AChE) for which we have found a remarkable trypanocidal activity, we have designed and synthesized novel benzo[h][1,6]naphthyridines, pyrrolo[3,2-c]quinolines, azepino[3,2-c]quinolines, and pyrano[3,2-c]quinolines through 2–4-step sequences featuring an initial multicomponent Povarov reaction as the key step. To assess the therapeutic potential of the novel compounds, we have evaluated their in vitro activity against T. brucei, T. cruzi, and Leishmania infantum, as well as their brain permeability, which is of specific interest for the treatment of late-stage HAT. To assess their potential toxicity, we have determined their cytotoxicity against rat myoblast L6 cells and their AChE inhibitory activity. Several tricyclic heterofused quinoline derivatives were found to display an interesting multi-trypanosomatid profile, with one-digit micromolar potencies against two of these parasites and two-digit micromolar potency against the other. Pyranoquinoline 39, which displays IC50 values of 1.5 μM, 6.1 μM and 29.2 μM against T. brucei, L. infantum and T. cruzi, respectively, brain permeability, better drug-like properties (lower lipophilicity and molecular weight and higher CNS MPO desirability score) than hit 1, and the lowest AChE inhibitory activity of the series (IC50 > 30 μM), emerges as an interesting multi-trypanosomatid lead, amenable to further optimization particularly in terms of its selectivity index over mammalian cells. Novel classes of tricyclic heterofused quinolines have been synthesized. Their 2–4-step syntheses involve a multicomponent Povarov reaction as the key step. Some compounds exhibit single digit micromolar potencies against 2 trypanosomatids. All compounds with multi-trypanosomatid activity can cross the blood–brain barrier. Most compounds with multi-trypanosomatid activity have drug like properties.
Collapse
Affiliation(s)
- Ornella Di Pietro
- Laboratori de Química Farmacèutica (Unitat Associada al CSIC), Facultat de Farmàcia, and Institut de Biomedicina (IBUB), Universitat de Barcelona, Av. Joan XXIII, 27-31, E-08028, Barcelona, Spain
| | | | - Martin C Taylor
- Department of Pathogen Molecular Biology, London School of Hygiene and Tropical Medicine, Keppel Street, London WC1E 7HT, United Kingdom
| | - Diana Berenguer
- Laboratori de Parasitologia, Departament de Microbiologia i Parasitologia Sanitàries, Facultat de Farmàcia, Universitat de Barcelona, Av. Joan XXIII, 27-31, E-08028, Barcelona, Spain
| | - Elisabet Viayna
- Laboratori de Química Farmacèutica (Unitat Associada al CSIC), Facultat de Farmàcia, and Institut de Biomedicina (IBUB), Universitat de Barcelona, Av. Joan XXIII, 27-31, E-08028, Barcelona, Spain
| | - Anna Lanzoni
- Laboratori de Química Farmacèutica (Unitat Associada al CSIC), Facultat de Farmàcia, and Institut de Biomedicina (IBUB), Universitat de Barcelona, Av. Joan XXIII, 27-31, E-08028, Barcelona, Spain
| | - Irene Sola
- Laboratori de Química Farmacèutica (Unitat Associada al CSIC), Facultat de Farmàcia, and Institut de Biomedicina (IBUB), Universitat de Barcelona, Av. Joan XXIII, 27-31, E-08028, Barcelona, Spain
| | - Helena Sayago
- Barcelona Science Park, Baldiri Reixac, 10-12, E-08028, Barcelona, Spain
| | - Cristina Riera
- Laboratori de Parasitologia, Departament de Microbiologia i Parasitologia Sanitàries, Facultat de Farmàcia, Universitat de Barcelona, Av. Joan XXIII, 27-31, E-08028, Barcelona, Spain
| | - Roser Fisa
- Laboratori de Parasitologia, Departament de Microbiologia i Parasitologia Sanitàries, Facultat de Farmàcia, Universitat de Barcelona, Av. Joan XXIII, 27-31, E-08028, Barcelona, Spain
| | - M Victòria Clos
- Departament de Farmacologia, de Terapèutica i de Toxicologia, Institut de Neurociències, Universitat Autònoma de Barcelona, E-08193, Bellaterra, Barcelona, Spain
| | - Belén Pérez
- Departament de Farmacologia, de Terapèutica i de Toxicologia, Institut de Neurociències, Universitat Autònoma de Barcelona, E-08193, Bellaterra, Barcelona, Spain
| | - John M Kelly
- Department of Pathogen Molecular Biology, London School of Hygiene and Tropical Medicine, Keppel Street, London WC1E 7HT, United Kingdom
| | - Rodolfo Lavilla
- Barcelona Science Park, Baldiri Reixac, 10-12, E-08028, Barcelona, Spain; Laboratori de Química Orgànica, Facultat de Farmàcia, Universitat de Barcelona, Av. Joan XXIII, 27-31, E-08028, Barcelona, Spain
| | - Diego Muñoz-Torrero
- Laboratori de Química Farmacèutica (Unitat Associada al CSIC), Facultat de Farmàcia, and Institut de Biomedicina (IBUB), Universitat de Barcelona, Av. Joan XXIII, 27-31, E-08028, Barcelona, Spain.
| |
Collapse
|
37
|
Radford GE, Taylor MC, Kieser JA, Waddell JN, Walsh KAJ, Schofield JC, Das R, Chakravorty E. Simulating backspatter of blood from cranial gunshot wounds using pig models. Int J Legal Med 2015; 130:985-994. [PMID: 26156450 DOI: 10.1007/s00414-015-1219-x] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/10/2015] [Accepted: 06/22/2015] [Indexed: 11/29/2022]
Abstract
Few studies have examined the biomechanical basis for backspatter from cranial gunshot wounds. Backspatter is material which travels against the direction of fire following ejection from a gunshot entrance wound. Our paper focuses on the use of animals for reconstructing this phenomenon. Five live pigs and several slaughtered pigs were shot using either 9 × 19 mm, 115 grain, full metal jacketed ammunition or .22 long rifle, 40 grain, lead, round-nose ammunition. A high-speed camera was used to record the entrance wound formation and backspatter. A small amount of backspattered material was produced with all targets, and blood backspatter was seen in a few cases. However, we conclude that our model provides an understanding of the phenomenon of backspatter and the physical mechanisms associated with it. The various components of the mechanism of backspatter formation are complex and overlap. The principle mechanism observed in pig cranial gunshots was the high-speed impact response of the skin overlying the skull bone. This study has also produced evidence supporting the view that backspatter can result from the splashing of superficial blood if it is already present on the skin. Subcutaneous gas effects have been demonstrated for backspatter from contact shots. There has been no clear evidence of the role of the collapse of a temporary cavity within the brain.
Collapse
Affiliation(s)
- G E Radford
- University of Otago, PO Box 54, Dunedin, 9054, New Zealand
| | - M C Taylor
- Institute of Environmental Science and Research (ESR), Christchurch Science Centre, 27 Creyke Rd, Christchurch, 8041, New Zealand.
| | - J A Kieser
- Sir John Walsh Research Institute, Faculty of Dentistry, University of Otago, PO Box 647, Dunedin, 9054, New Zealand
| | - J N Waddell
- Sir John Walsh Research Institute, Faculty of Dentistry, University of Otago, PO Box 647, Dunedin, 9054, New Zealand
| | - K A J Walsh
- Institute of Environmental Science and Research (ESR), Mount Albert Science Centre, 120 Mount Albert Road, Auckland, 1142, New Zealand
| | - J C Schofield
- University of Otago, PO Box 54, Dunedin, 9054, New Zealand
| | - R Das
- Department of Mechanical Engineering, University of Auckland, Auckland, 1010, New Zealand
| | - E Chakravorty
- Department of Mechanical Engineering, University of Auckland, Auckland, 1010, New Zealand
| |
Collapse
|
38
|
Taylor MC, Lewis MD, Francisco AF, Wilkinson SR, Kelly JM. The Trypanosoma cruzi vitamin C dependent peroxidase confers protection against oxidative stress but is not a determinant of virulence. PLoS Negl Trop Dis 2015; 9:e0003707. [PMID: 25875298 PMCID: PMC4395405 DOI: 10.1371/journal.pntd.0003707] [Citation(s) in RCA: 27] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/06/2014] [Accepted: 03/17/2015] [Indexed: 11/18/2022] Open
Abstract
BACKGROUND The neglected parasitic infection Chagas disease is rapidly becoming a globalised public health issue due to migration. There are only two anti-parasitic drugs available to treat this disease, benznidazole and nifurtimox. Thus it is important to identify and validate new drug targets in Trypanosoma cruzi, the causative agent. T. cruzi expresses an ER-localised ascorbate-dependent peroxidase (TcAPx). This parasite-specific enzyme has attracted interest from the perspective of targeted chemotherapy. METHODOLOGY/PRINCIPAL FINDINGS To assess the importance of TcAPx in protecting T. cruzi from oxidative stress and to determine if it is essential for virulence, we generated null mutants by targeted gene disruption. Loss of activity was associated with increased sensitivity to exogenous hydrogen peroxide, but had no effect on susceptibility to the front-line Chagas disease drug benznidazole. This suggests that increased oxidative stress in the ER does not play a significant role in its mechanism of action. Homozygous knockouts could proceed through the entire life-cycle in vitro, although they exhibited a significant decrease in their ability to infect mammalian cells. To investigate virulence, we exploited a highly sensitive bioluminescence imaging system which allows parasites to be monitored in real-time in the chronic stage of murine infections. This showed that depletion of enzyme activity had no effect on T. cruzi replication, dissemination or tissue tropism in vivo. CONCLUSIONS/SIGNIFICANCE TcAPx is not essential for parasite viability within the mammalian host, does not have a significant role in establishment or maintenance of chronic infections, and should therefore not be considered a priority for drug design.
Collapse
Affiliation(s)
- Martin C. Taylor
- Faculty of Infectious and Tropical Diseases, London School of Hygiene and Tropical Medicine, London, United Kingdom
- * E-mail:
| | - Michael D. Lewis
- Faculty of Infectious and Tropical Diseases, London School of Hygiene and Tropical Medicine, London, United Kingdom
| | - Amanda Fortes Francisco
- Faculty of Infectious and Tropical Diseases, London School of Hygiene and Tropical Medicine, London, United Kingdom
| | - Shane R. Wilkinson
- School of Biological and Chemical Sciences, Queen Mary University of London, London, United Kingdom
| | - John M. Kelly
- Faculty of Infectious and Tropical Diseases, London School of Hygiene and Tropical Medicine, London, United Kingdom
| |
Collapse
|
39
|
Sola I, Castellà S, Viayna E, Galdeano C, Taylor MC, Gbedema SY, Pérez B, Clos MV, Jones DC, Fairlamb AH, Wright CW, Kelly JM, Muñoz-Torrero D. Synthesis, biological profiling and mechanistic studies of 4-aminoquinoline-based heterodimeric compounds with dual trypanocidal-antiplasmodial activity. Bioorg Med Chem 2015; 23:5156-67. [PMID: 25678015 DOI: 10.1016/j.bmc.2015.01.031] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/14/2014] [Revised: 01/16/2015] [Accepted: 01/19/2015] [Indexed: 12/13/2022]
Abstract
Dual submicromolar trypanocidal-antiplasmodial compounds have been identified by screening and chemical synthesis of 4-aminoquinoline-based heterodimeric compounds of three different structural classes. In Trypanosoma brucei, inhibition of the enzyme trypanothione reductase seems to be involved in the potent trypanocidal activity of these heterodimers, although it is probably not the main biological target. Regarding antiplasmodial activity, the heterodimers seem to share the mode of action of the antimalarial drug chloroquine, which involves inhibition of the haem detoxification process. Interestingly, all of these heterodimers display good brain permeabilities, thereby being potentially useful for late stage human African trypanosomiasis. Future optimization of these compounds should focus mainly on decreasing cytotoxicity and acetylcholinesterase inhibitory activity.
Collapse
Affiliation(s)
- Irene Sola
- Laboratori de Química Farmacèutica (Unitat Associada al CSIC), Facultat de Farmàcia, and Institut de Biomedicina (IBUB), Universitat de Barcelona, Av. Joan XXIII, 27-31, E-08028 Barcelona, Spain
| | - Sílvia Castellà
- Laboratori de Química Farmacèutica (Unitat Associada al CSIC), Facultat de Farmàcia, and Institut de Biomedicina (IBUB), Universitat de Barcelona, Av. Joan XXIII, 27-31, E-08028 Barcelona, Spain
| | - Elisabet Viayna
- Laboratori de Química Farmacèutica (Unitat Associada al CSIC), Facultat de Farmàcia, and Institut de Biomedicina (IBUB), Universitat de Barcelona, Av. Joan XXIII, 27-31, E-08028 Barcelona, Spain
| | - Carles Galdeano
- Laboratori de Química Farmacèutica (Unitat Associada al CSIC), Facultat de Farmàcia, and Institut de Biomedicina (IBUB), Universitat de Barcelona, Av. Joan XXIII, 27-31, E-08028 Barcelona, Spain
| | - Martin C Taylor
- Department of Pathogen Molecular Biology, London School of Hygiene and Tropical Medicine, Keppel Street, London WC1E 7HT, United Kingdom
| | - Stephen Y Gbedema
- Bradford School of Pharmacy, University of Bradford, West Yorkshire BD7 1 DP, United Kingdom; Department of Pharmaceutics, Kwame Nkrumah University of Science and Technology, Kumasi, Ghana
| | - Belén Pérez
- Departament de Farmacologia, de Terapèutica i de Toxicologia, Universitat Autònoma de Barcelona, 08193-Bellaterra, Barcelona, Spain
| | - M Victòria Clos
- Departament de Farmacologia, de Terapèutica i de Toxicologia, Universitat Autònoma de Barcelona, 08193-Bellaterra, Barcelona, Spain
| | - Deuan C Jones
- Division of Biological Chemistry & Drug Discovery, College of Life Sciences, University of Dundee, Dundee DD1 5EH, United Kingdom
| | - Alan H Fairlamb
- Division of Biological Chemistry & Drug Discovery, College of Life Sciences, University of Dundee, Dundee DD1 5EH, United Kingdom
| | - Colin W Wright
- Bradford School of Pharmacy, University of Bradford, West Yorkshire BD7 1 DP, United Kingdom
| | - John M Kelly
- Department of Pathogen Molecular Biology, London School of Hygiene and Tropical Medicine, Keppel Street, London WC1E 7HT, United Kingdom
| | - Diego Muñoz-Torrero
- Laboratori de Química Farmacèutica (Unitat Associada al CSIC), Facultat de Farmàcia, and Institut de Biomedicina (IBUB), Universitat de Barcelona, Av. Joan XXIII, 27-31, E-08028 Barcelona, Spain.
| |
Collapse
|
40
|
Sola I, Artigas A, Taylor MC, Gbedema SY, Pérez B, Clos MV, Wright CW, Kelly JM, Muñoz-Torrero D. Synthesis and antiprotozoal activity of oligomethylene- and p-phenylene-bis(methylene)-linked bis(+)-huprines. Bioorg Med Chem Lett 2014; 24:5435-8. [DOI: 10.1016/j.bmcl.2014.10.025] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/25/2014] [Revised: 10/04/2014] [Accepted: 10/08/2014] [Indexed: 01/24/2023]
|
41
|
Shameer S, Logan-Klumpler FJ, Vinson F, Cottret L, Merlet B, Achcar F, Boshart M, Berriman M, Breitling R, Bringaud F, Bütikofer P, Cattanach AM, Bannerman-Chukualim B, Creek DJ, Crouch K, de Koning HP, Denise H, Ebikeme C, Fairlamb AH, Ferguson MAJ, Ginger ML, Hertz-Fowler C, Kerkhoven EJ, Mäser P, Michels PAM, Nayak A, Nes DW, Nolan DP, Olsen C, Silva-Franco F, Smith TK, Taylor MC, Tielens AGM, Urbaniak MD, van Hellemond JJ, Vincent IM, Wilkinson SR, Wyllie S, Opperdoes FR, Barrett MP, Jourdan F. TrypanoCyc: a community-led biochemical pathways database for Trypanosoma brucei. Nucleic Acids Res 2014; 43:D637-44. [PMID: 25300491 PMCID: PMC4384016 DOI: 10.1093/nar/gku944] [Citation(s) in RCA: 22] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/23/2022] Open
Abstract
The metabolic network of a cell represents the catabolic and anabolic reactions that interconvert small molecules (metabolites) through the activity of enzymes, transporters and non-catalyzed chemical reactions. Our understanding of individual metabolic networks is increasing as we learn more about the enzymes that are active in particular cells under particular conditions and as technologies advance to allow detailed measurements of the cellular metabolome. Metabolic network databases are of increasing importance in allowing us to contextualise data sets emerging from transcriptomic, proteomic and metabolomic experiments. Here we present a dynamic database, TrypanoCyc (http://www.metexplore.fr/trypanocyc/), which describes the generic and condition-specific metabolic network of Trypanosoma brucei, a parasitic protozoan responsible for human and animal African trypanosomiasis. In addition to enabling navigation through the BioCyc-based TrypanoCyc interface, we have also implemented a network-based representation of the information through MetExplore, yielding a novel environment in which to visualise the metabolism of this important parasite.
Collapse
Affiliation(s)
- Sanu Shameer
- Institut National de la Recherche Agronomique (INRA), UMR1331, TOXALIM (Research Centre in Food Toxicology), Université de Toulouse, Toulouse, France
| | | | - Florence Vinson
- Institut National de la Recherche Agronomique (INRA), UMR1331, TOXALIM (Research Centre in Food Toxicology), Université de Toulouse, Toulouse, France
| | - Ludovic Cottret
- Institut National de la Recherche Agronomique (INRA), UMR441, Laboratoire des Interactions Plantes-Microorganismes (LIPM), Auzeville, France
| | - Benjamin Merlet
- Institut National de la Recherche Agronomique (INRA), UMR1331, TOXALIM (Research Centre in Food Toxicology), Université de Toulouse, Toulouse, France
| | - Fiona Achcar
- University of Glasgow, Glasgow, Scotland, G12 8QQ, UK
| | - Michael Boshart
- Ludwig-Maximilians-Universität München, Biocenter, 82152-Martinsried, Germany
| | - Matthew Berriman
- The Wellcome Trust Sanger Institute, Hinxton, Cambridge CB10 1SA, UK
| | - Rainer Breitling
- Manchester Institute of Biotechnology, Faculty of Life Sciences, University of Manchester, Manchester, UK
| | | | | | | | | | - Darren J Creek
- Monash Institute of Pharmaceutical Sciences, Monash University, Parkville 3052, Australia
| | | | | | - Hubert Denise
- European Bioinformatics Institute (EMBL-EBI), Hinxton, Cambridge, CB10 1SD, UK
| | | | | | | | - Michael L Ginger
- Divisionof Biomedical and Life Sciences, Lancaster University, Bailrigg, Lancaster, LA1 4YG, UK
| | | | - Eduard J Kerkhoven
- Chalmers University of Technology, Kemivägen 10, 412 96, Göteborg, Sweden
| | - Pascal Mäser
- Swiss Tropical and Public Health Institute, Socinstr. 57, Basel 4051, Switzerland
| | | | - Archana Nayak
- University of Glasgow, Glasgow, Scotland, G12 8QQ, UK
| | | | | | | | | | - Terry K Smith
- University of St Andrews, St Andrews, Scotland, KY16 9ST, UK
| | | | - Aloysius G M Tielens
- Utrecht University, Utrecht, 3508 TD, The Netherlands Erasmus University Medical Center, Rotterdam, 3015 CE, The Netherlands
| | - Michael D Urbaniak
- Divisionof Biomedical and Life Sciences, Lancaster University, Bailrigg, Lancaster, LA1 4YG, UK
| | | | | | | | - Susan Wyllie
- University of Dundee, Dundee, Scotland, DD1 4HN, UK
| | | | | | - Fabien Jourdan
- Institut National de la Recherche Agronomique (INRA), UMR1331, TOXALIM (Research Centre in Food Toxicology), Université de Toulouse, Toulouse, France
| |
Collapse
|
42
|
Lewis MD, Francisco AF, Taylor MC, Kelly JM. A new experimental model for assessing drug efficacy against Trypanosoma cruzi infection based on highly sensitive in vivo imaging. ACTA ACUST UNITED AC 2014; 20:36-43. [PMID: 25296657 PMCID: PMC4361455 DOI: 10.1177/1087057114552623] [Citation(s) in RCA: 73] [Impact Index Per Article: 7.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/18/2022]
Abstract
The protozoan Trypanosoma cruzi is the causative agent of Chagas disease, one of the world’s major neglected infections. Although development of improved antiparasitic drugs is considered a priority, there have been no significant treatment advances in the past 40 years. Factors that have limited progress include an incomplete understanding of pathogenesis, tissue tropism, and disease progression. In addition, in vivo models, which allow parasite burdens to be tracked throughout the chronic stage of infection, have been lacking. To address these issues, we have developed a highly sensitive in vivo imaging system based on bioluminescent T. cruzi, which express a red-shifted luciferase that emits light in the tissue-penetrating orange-red region of the spectrum. The exquisite sensitivity of this noninvasive murine model has been exploited to monitor parasite burden in real time throughout the chronic stage, has allowed the identification of the gastrointestinal tract as the major niche of long-term infection, and has demonstrated that chagasic heart disease can develop in the absence of locally persistent parasites. Here, we review the parameters of the imaging system and describe how this experimental model can be incorporated into drug development programs as a valuable tool for assessing efficacy against both acute and chronic T. cruzi infections.
Collapse
Affiliation(s)
- Michael D Lewis
- Department of Pathogen Molecular Biology, London School of Hygiene and Tropical Medicine, London WC1E 7HT, UK
| | - Amanda Fortes Francisco
- Department of Pathogen Molecular Biology, London School of Hygiene and Tropical Medicine, London WC1E 7HT, UK
| | - Martin C Taylor
- Department of Pathogen Molecular Biology, London School of Hygiene and Tropical Medicine, London WC1E 7HT, UK
| | - John M Kelly
- Department of Pathogen Molecular Biology, London School of Hygiene and Tropical Medicine, London WC1E 7HT, UK
| |
Collapse
|
43
|
Lewis MD, Fortes Francisco A, Taylor MC, Burrell-Saward H, McLatchie AP, Miles MA, Kelly JM. Bioluminescence imaging of chronic Trypanosoma cruzi infections reveals tissue-specific parasite dynamics and heart disease in the absence of locally persistent infection. Cell Microbiol 2014; 16:1285-300. [PMID: 24712539 PMCID: PMC4190689 DOI: 10.1111/cmi.12297] [Citation(s) in RCA: 167] [Impact Index Per Article: 16.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/19/2014] [Accepted: 03/18/2014] [Indexed: 12/12/2022]
Abstract
Summary Chronic Trypanosoma cruzi infections lead to cardiomyopathy in 20–30% of cases. A causal link between cardiac infection and pathology has been difficult to establish because of a lack of robust methods to detect scarce, focally distributed parasites within tissues. We developed a highly sensitive bioluminescence imaging system based on T. cruzi expressing a novel luciferase that emits tissue-penetrating orange-red light. This enabled long-term serial evaluation of parasite burdens in individual mice with an in vivo limit of detection of significantly less than 1000 parasites. Parasite distributions during chronic infections were highly focal and spatiotemporally dynamic, but did not localize to the heart. End-point ex vivo bioluminescence imaging allowed tissue-specific quantification of parasite loads with minimal sampling bias. During chronic infections, the gastro-intestinal tract, specifically the colon and stomach, was the only site where T. cruzi infection was consistently observed. Quantitative PCR-inferred parasite loads correlated with ex vivo bioluminescence and confirmed the gut as the parasite reservoir. Chronically infected mice developed myocarditis and cardiac fibrosis, despite the absence of locally persistent parasites. These data identify the gut as a permissive niche for long-term T. cruzi infection and show that canonical features of Chagas disease can occur without continual myocardium-specific infection.
Collapse
Affiliation(s)
- Michael D Lewis
- Department of Pathogen Molecular Biology, Faculty of Infectious and Tropical Diseases, London School of Hygiene and Tropical Medicine, Keppel Street, London, WC1E 7HT, UK
| | | | | | | | | | | | | |
Collapse
|
44
|
Taylor MC, Kelly JM. Optimizing bioluminescence imaging to study protozoan parasite infections. Trends Parasitol 2014; 30:161-2. [PMID: 24485045 DOI: 10.1016/j.pt.2014.01.006] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/14/2014] [Revised: 01/15/2014] [Accepted: 01/15/2014] [Indexed: 11/28/2022]
Abstract
Bioluminescence imaging is a non-invasive technique which can be used to monitor infections in real-time. However, its utility is restricted by difficulties in detecting pathogens in deep tissue. 'Red-shifted' luciferases, which emit light of longer wavelength than standard bioluminescence-generating proteins, greatly enhance sensitivity, and have wide applicability for studying parasite infections.
Collapse
Affiliation(s)
- Martin C Taylor
- Department of Pathogen Molecular Biology, Faculty of Infectious and Tropical Diseases, London School of Hygiene and Tropical Medicine, Keppel Street, London WC1E 7HT, UK
| | - John M Kelly
- Department of Pathogen Molecular Biology, Faculty of Infectious and Tropical Diseases, London School of Hygiene and Tropical Medicine, Keppel Street, London WC1E 7HT, UK.
| |
Collapse
|
45
|
Campos MCO, Leon LL, Taylor MC, Kelly JM. Benznidazole-resistance in Trypanosoma cruzi: evidence that distinct mechanisms can act in concert. Mol Biochem Parasitol 2014; 193:17-9. [PMID: 24462750 PMCID: PMC3988956 DOI: 10.1016/j.molbiopara.2014.01.002] [Citation(s) in RCA: 65] [Impact Index Per Article: 6.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/31/2013] [Revised: 01/10/2014] [Accepted: 01/13/2014] [Indexed: 11/27/2022]
Abstract
Drug-resistance in T. cruzi can arise independently within a single population. Distinct mechanisms can contribute to benznidazole-resistance in T. cruzi. Stop-codon generating mutations in the TcNTR gene linked to benznidazole-resistance.
Benznidazole is the main drug used to treat Trypanosoma cruzi infections. However, frequent instances of treatment failure have been reported. To better understand potential resistance mechanisms, we analysed three clones isolated from a single parasite population that had undergone benznidazole-selection. These clones exhibited differing levels of benznidazole-resistance (varying between 9 and 26-fold), and displayed cross-resistance to nifurtimox (2 to 4-fold). Each clone had acquired a stop-codon-generating mutation in the gene which encodes the nitroreductase (TcNTR) that is responsible for activating nitroheterocyclic pro-drugs. In addition, one clone had lost a copy of the chromosome containing TcNTR. However, these processes alone are insufficient to account for the extent and diversity of benznidazole-resistance. It is implicit from our results that additional mechanisms must also operate and that T. cruzi has an intrinsic ability to develop drug-resistance by independent sequential steps, even within a single population. This has important implications for drug development strategies.
Collapse
Affiliation(s)
- Mônica C O Campos
- Department of Pathogen Molecular Biology, London School of Hygiene and Tropical Medicine, Keppel Street, London WC1E 7HT, UK; Laboratório de Bioquímica de Tripanosomatídeos, Instituto Oswaldo Cruz, IOC, Avenida Brasil 4365, Manguinhos, Fundação Oswaldo Cruz, Rio de Janeiro, Brazil.
| | - Leonor L Leon
- Laboratório de Bioquímica de Tripanosomatídeos, Instituto Oswaldo Cruz, IOC, Avenida Brasil 4365, Manguinhos, Fundação Oswaldo Cruz, Rio de Janeiro, Brazil.
| | - Martin C Taylor
- Department of Pathogen Molecular Biology, London School of Hygiene and Tropical Medicine, Keppel Street, London WC1E 7HT, UK.
| | - John M Kelly
- Department of Pathogen Molecular Biology, London School of Hygiene and Tropical Medicine, Keppel Street, London WC1E 7HT, UK.
| |
Collapse
|
46
|
McLatchie AP, Burrell-Saward H, Myburgh E, Lewis MD, Ward TH, Mottram JC, Croft SL, Kelly JM, Taylor MC. Highly sensitive in vivo imaging of Trypanosoma brucei expressing "red-shifted" luciferase. PLoS Negl Trop Dis 2013; 7:e2571. [PMID: 24278497 PMCID: PMC3836995 DOI: 10.1371/journal.pntd.0002571] [Citation(s) in RCA: 51] [Impact Index Per Article: 4.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/19/2013] [Accepted: 10/21/2013] [Indexed: 11/30/2022] Open
Abstract
Background Human African trypanosomiasis is caused by infection with parasites of the Trypanosoma brucei species complex, and threatens over 70 million people in sub-Saharan Africa. Development of new drugs is hampered by the limitations of current rodent models, particularly for stage II infections, which occur once parasites have accessed the CNS. Bioluminescence imaging of pathogens expressing firefly luciferase (emission maximum 562 nm) has been adopted in a number of in vivo models of disease to monitor dissemination, drug-treatment and the role of immune responses. However, lack of sensitivity in detecting deep tissue bioluminescence at wavelengths below 600 nm has restricted the wide-spread use of in vivo imaging to investigate infections with T. brucei and other trypanosomatids. Methodology/Principal findings Here, we report a system that allows the detection of fewer than 100 bioluminescent T. brucei parasites in a murine model. As a reporter, we used a codon-optimised red-shifted Photinus pyralis luciferase (PpyRE9H) with a peak emission of 617 nm. Maximal expression was obtained following targeted integration of the gene, flanked by an upstream 5′-variant surface glycoprotein untranslated region (UTR) and a downstream 3′-tubulin UTR, into a T. brucei ribosomal DNA locus. Expression was stable in the absence of selective drug for at least 3 months and was not associated with detectable phenotypic changes. Parasite dissemination and drug efficacy could be monitored in real time, and brain infections were readily detectable. The level of sensitivity in vivo was significantly greater than achievable with a yellow firefly luciferase reporter. Conclusions/Significance The optimised bioluminescent reporter line described here will significantly enhance the application of in vivo imaging to study stage II African trypanosomiasis in murine models. The greatly increased sensitivity provides a new framework for investigating host-parasite relationships, particularly in the context of CNS infections. It should be ideally suited to drug evaluation programmes. Parasites of the Trypanosoma brucei species complex are the causative agents of human African trypanosomiasis. There is an urgent need for new drugs to treat this debilitating and potentially fatal infection, especially in its late stage, when parasites have entered the central nervous system. Factors which hamper drug development include the limitations of the current murine models for stage II disease. In vivo bioluminescence imaging is a non-invasive technique that can be used to monitor infections in real time and is a powerful new approach for studying drug effectiveness. However, application of this imaging technology to trypanosome infections has been restricted because of lack of sensitivity. In this paper, we have taken a major step to resolve this problem. The enhanced sensitivity in infected mice is based on the high level expression in trypanosomes of a “red-shifted” luciferase variant that greatly improves bioluminescence detection in deep tissue. The system which we have developed should be a widely applicable tool for providing new insights into the infection biology of T. brucei.
Collapse
Affiliation(s)
- Alex P. McLatchie
- Faculty of Infectious and Tropical Diseases, London School of Hygiene and Tropical Medicine, London, United Kingdom
| | - Hollie Burrell-Saward
- Faculty of Infectious and Tropical Diseases, London School of Hygiene and Tropical Medicine, London, United Kingdom
| | - Elmarie Myburgh
- Wellcome Trust Centre for Molecular Parasitology, Institute of Infection, Immunity and Inflammation, University of Glasgow, Glasgow, United Kingdom
| | - Michael D. Lewis
- Faculty of Infectious and Tropical Diseases, London School of Hygiene and Tropical Medicine, London, United Kingdom
| | - Theresa H. Ward
- Faculty of Infectious and Tropical Diseases, London School of Hygiene and Tropical Medicine, London, United Kingdom
| | - Jeremy C. Mottram
- Wellcome Trust Centre for Molecular Parasitology, Institute of Infection, Immunity and Inflammation, University of Glasgow, Glasgow, United Kingdom
| | - Simon L. Croft
- Faculty of Infectious and Tropical Diseases, London School of Hygiene and Tropical Medicine, London, United Kingdom
| | - John M. Kelly
- Faculty of Infectious and Tropical Diseases, London School of Hygiene and Tropical Medicine, London, United Kingdom
- * E-mail:
| | - Martin C. Taylor
- Faculty of Infectious and Tropical Diseases, London School of Hygiene and Tropical Medicine, London, United Kingdom
| |
Collapse
|
47
|
Myburgh E, Coles JA, Ritchie R, Kennedy PGE, McLatchie AP, Rodgers J, Taylor MC, Barrett MP, Brewer JM, Mottram JC. In vivo imaging of trypanosome-brain interactions and development of a rapid screening test for drugs against CNS stage trypanosomiasis. PLoS Negl Trop Dis 2013; 7:e2384. [PMID: 23991236 PMCID: PMC3749981 DOI: 10.1371/journal.pntd.0002384] [Citation(s) in RCA: 53] [Impact Index Per Article: 4.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/18/2013] [Accepted: 07/13/2013] [Indexed: 11/18/2022] Open
Abstract
HUMAN AFRICAN TRYPANOSOMIASIS (HAT) MANIFESTS IN TWO STAGES OF DISEASE: firstly, haemolymphatic, and secondly, an encephalitic phase involving the central nervous system (CNS). New drugs to treat the second-stage disease are urgently needed, yet testing of novel drug candidates is a slow process because the established animal model relies on detecting parasitemia in the blood as late as 180 days after treatment. To expedite compound screening, we have modified the GVR35 strain of Trypanosoma brucei brucei to express luciferase, and have monitored parasite distribution in infected mice following treatment with trypanocidal compounds using serial, non-invasive, bioluminescence imaging. Parasites were detected in the brains of infected mice following treatment with diminazene, a drug which cures stage 1 but not stage 2 disease. Intravital multi-photon microscopy revealed that trypanosomes enter the brain meninges as early as day 5 post-infection but can be killed by diminazene, whereas those that cross the blood-brain barrier and enter the parenchyma by day 21 survived treatment and later caused bloodstream recrudescence. In contrast, all bioluminescent parasites were permanently eliminated by treatment with melarsoprol and DB829, compounds known to cure stage 2 disease. We show that this use of imaging reduces by two thirds the time taken to assess drug efficacy and provides a dual-modal imaging platform for monitoring trypanosome infection in different areas of the brain.
Collapse
Affiliation(s)
- Elmarie Myburgh
- Wellcome Trust Centre for Molecular Parasitology, College of Medical, Veterinary and Life Sciences, University of Glasgow, Glasgow, United Kingdom
- Institute of Infection, Immunity and Inflammation, College of Medical, Veterinary and Life Sciences, University of Glasgow, Glasgow, United Kingdom
| | - Jonathan A. Coles
- Wellcome Trust Centre for Molecular Parasitology, College of Medical, Veterinary and Life Sciences, University of Glasgow, Glasgow, United Kingdom
- Institute of Infection, Immunity and Inflammation, College of Medical, Veterinary and Life Sciences, University of Glasgow, Glasgow, United Kingdom
| | - Ryan Ritchie
- Wellcome Trust Centre for Molecular Parasitology, College of Medical, Veterinary and Life Sciences, University of Glasgow, Glasgow, United Kingdom
- Institute of Infection, Immunity and Inflammation, College of Medical, Veterinary and Life Sciences, University of Glasgow, Glasgow, United Kingdom
| | - Peter G. E. Kennedy
- Institute of Infection, Immunity and Inflammation, College of Medical, Veterinary and Life Sciences, University of Glasgow, Glasgow, United Kingdom
| | - Alex P. McLatchie
- Faculty of Infectious and Tropical Diseases, London School of Hygiene and Tropical Medicine, London, United Kingdom
| | - Jean Rodgers
- Institute of Infection, Immunity and Inflammation, College of Medical, Veterinary and Life Sciences, University of Glasgow, Glasgow, United Kingdom
| | - Martin C. Taylor
- Faculty of Infectious and Tropical Diseases, London School of Hygiene and Tropical Medicine, London, United Kingdom
| | - Michael P. Barrett
- Wellcome Trust Centre for Molecular Parasitology, College of Medical, Veterinary and Life Sciences, University of Glasgow, Glasgow, United Kingdom
- Institute of Infection, Immunity and Inflammation, College of Medical, Veterinary and Life Sciences, University of Glasgow, Glasgow, United Kingdom
- * E-mail:
| | - James M. Brewer
- Wellcome Trust Centre for Molecular Parasitology, College of Medical, Veterinary and Life Sciences, University of Glasgow, Glasgow, United Kingdom
- Institute of Infection, Immunity and Inflammation, College of Medical, Veterinary and Life Sciences, University of Glasgow, Glasgow, United Kingdom
| | - Jeremy C. Mottram
- Wellcome Trust Centre for Molecular Parasitology, College of Medical, Veterinary and Life Sciences, University of Glasgow, Glasgow, United Kingdom
- Institute of Infection, Immunity and Inflammation, College of Medical, Veterinary and Life Sciences, University of Glasgow, Glasgow, United Kingdom
| |
Collapse
|
48
|
Taylor MC, McLatchie AP, Kelly JM. Evidence that transport of iron from the lysosome to the cytosol in African trypanosomes is mediated by a mucolipin orthologue. Mol Microbiol 2013; 89:420-32. [PMID: 23750752 PMCID: PMC3828870 DOI: 10.1111/mmi.12285] [Citation(s) in RCA: 20] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 06/02/2013] [Indexed: 11/28/2022]
Abstract
Bloodstream-form Trypanosoma brucei acquire iron by receptor-mediated endocytosis of host transferrin. However, the mechanism(s) by which iron is then transferred from the lysosome to the cytosol are unresolved. Here, we provide evidence for the involvement of a protein (TbMLP) orthologous to the mammalian endolysosomal cation channel Mucolipin 1. In T. brucei, we show that this protein is localized to the single parasite lysosome. TbMLP null mutants could only be generated in the presence of an expressed ectopic copy, suggesting that the protein is essential. RNAi-mediated ablation resulted in a growth defect in vitro and led to a sevenfold increase in susceptibility to the iron-chelators deferoxamine and salicylhydroxamic acid. Conditional null mutants remained viable when the ectopic copy was repressed, but were hypersensitive to deferoxamine and displayed a growth defect similar to that observed following RNAi. The conditional nulls also retained virulence in vivo in the absence of the doxycycline inducer. These data provide strong evidence that TbMLP has a role in import of iron into the cytosol of African trypanosomes. They also indicate that even when expression is greatly reduced, there is sufficient protein, or an alternative mechanism, to provide the parasite with an adequate supply of cytosolic iron.
Collapse
Affiliation(s)
- Martin C Taylor
- Department of Pathogen Molecular Biology, London School of Hygiene and Tropical Medicine, Keppel St., London, WC1E 7HT, UK.
| | | | | |
Collapse
|
49
|
Koperniku A, Papanastasiou I, Foscolos GB, Tsotinis A, Taylor MC, Kelly JM. Synthesis and trypanocidal action of new adamantane substituted imidazolines. Med Chem Commun 2013. [DOI: 10.1039/c3md00081h] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
|
50
|
Mejia AM, Hall BS, Taylor MC, Gómez-Palacio A, Wilkinson SR, Triana-Chávez O, Kelly JM. Benznidazole-resistance in Trypanosoma cruzi is a readily acquired trait that can arise independently in a single population. J Infect Dis 2012; 206:220-8. [PMID: 22551809 PMCID: PMC3379838 DOI: 10.1093/infdis/jis331] [Citation(s) in RCA: 97] [Impact Index Per Article: 8.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/12/2022] Open
Abstract
Benznidazole is the frontline drug used against Trypanosoma cruzi, the causative agent of Chagas disease. However, treatment failures are often reported. Here, we demonstrate that independently acquired mutations in the gene encoding a mitochondrial nitroreductase (TcNTR) can give rise to distinct drug-resistant clones within a single population. Following selection of benznidazole-resistant parasites, all clones examined had lost one of the chromosomes containing the TcNTR gene. Sequence analysis of the remaining TcNTR allele revealed 3 distinct mutant genes in different resistant clones. Expression studies showed that these mutant proteins were unable to activate benznidazole. This correlated with loss of flavin mononucleotide binding. The drug-resistant phenotype could be reversed by transfection with wild-type TcNTR. These results identify TcNTR as a central player in acquired resistance to benznidazole. They also demonstrate that T. cruzi has a propensity to undergo genetic changes that can lead to drug resistance, a finding that has implications for future therapeutic strategies.
Collapse
Affiliation(s)
- Ana Maria Mejia
- Department of Pathogen Molecular Biology, London School of Hygiene and Tropical Medicine, University of London, United Kingdom
| | | | | | | | | | | | | |
Collapse
|