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Erban T, Parizkova K, Sopko B, Talacko P, Markovic M, Jarosova J, Votypka J. Imidacloprid increases the prevalence of the intestinal parasite Lotmaria passim in honey bee workers. THE SCIENCE OF THE TOTAL ENVIRONMENT 2023; 905:166973. [PMID: 37699488 DOI: 10.1016/j.scitotenv.2023.166973] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/26/2023] [Revised: 09/05/2023] [Accepted: 09/08/2023] [Indexed: 09/14/2023]
Abstract
A challenge in bee protection is to assess the risks of pesticide-pathogen interactions. Lotmaria passim, a ubiquitous unicellular parasite in honey bees, is considered harmful under specific conditions. Imidacloprid causes unpredictable side effects. Research indicates that both L. passim and imidacloprid may affect the physiology, behavior, immunity, microbiome and lifespan of honey bees. We designed cage experiments to test whether the infection of L. passim is affected by a sublethal dose of imidacloprid. Workers collected at the time of emergence were exposed to L. passim and 2.5 μg/L imidacloprid in the coexposure treatment group. First, samples of bees were taken from cages since they were 5 days old and 3 days postinfection, i.e., after finishing an artificial 24 h L. passim infection. Additional bees were collected every two additional days. In addition, bees frozen at the time of emergence and collected from the unexposed group were analyzed. Abdomens were analyzed using qPCR to determine parasite load, while corresponding selected heads were subjected to a label-free proteomic analysis. Our results show that bees are free of L. passim at the time of emergence. Furthermore, imidacloprid considerably increased the prevalence as well as parasite loads in individual bees. This means that imidacloprid facilitates infection, enabling faster parasite spread in a colony and potentially to surrounding colonies. The proteomic analysis of bee heads showed that imidacloprid neutralized the increased transferrin 1 expression by L. passim. Importantly, this promising marker has been previously observed to be upregulated by infections, including gut parasites. This study contributes to understanding the side effects of imidacloprid and demonstrates that a single xenobiotic/pesticide compound can interact with the gut parasite. Our methodology can be used to assess the effects of different compounds on L. passim.
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Affiliation(s)
- Tomas Erban
- Proteomics and Metabolomics Laboratory, Crop Research Institute, Drnovska 507/73, Prague 6-Ruzyne CZ-161 06, Czechia.
| | - Kamila Parizkova
- Department of Parasitology, Faculty of Science, Charles University, Vinicna 1594/7, Prague 2 CZ-128 00, Czechia
| | - Bruno Sopko
- Proteomics and Metabolomics Laboratory, Crop Research Institute, Drnovska 507/73, Prague 6-Ruzyne CZ-161 06, Czechia
| | - Pavel Talacko
- Proteomics Core Facility, Faculty of Science, BIOCEV, Charles University, Prumyslova 595, Vestec CZ-252 50, Czechia
| | - Martin Markovic
- Proteomics and Metabolomics Laboratory, Crop Research Institute, Drnovska 507/73, Prague 6-Ruzyne CZ-161 06, Czechia
| | - Jana Jarosova
- Laboratory of Hormonal Regulations in Plants, Institute of Experimental Botany, Czech Academy of Sciences, Rozvojova 263, Prague 6-Lysolaje CZ-165 02, Czechia
| | - Jan Votypka
- Department of Parasitology, Faculty of Science, Charles University, Vinicna 1594/7, Prague 2 CZ-128 00, Czechia; Institute of Parasitology, Biology Centre, Czech Academy of Sciences, Branisovska 1160/31, Ceske Budejovice CZ-37005, Czechia
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2
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Racané L, Ptiček L, Kostrun S, Raić-Malić S, Taylor MC, Delves M, Alsford S, Olmo F, Francisco AF, Kelly JM. Bis-6-amidino-benzothiazole Derivative that Cures Experimental Stage 1 African Trypanosomiasis with a Single Dose. J Med Chem 2023; 66:13043-13057. [PMID: 37722077 PMCID: PMC10544003 DOI: 10.1021/acs.jmedchem.3c01051] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/12/2023] [Indexed: 09/20/2023]
Abstract
We designed and synthesized a series of symmetric bis-6-amidino-benzothiazole derivatives with aliphatic central units and evaluated their efficacy against bloodstream forms of the African trypanosome Trypanosoma brucei. Of these, a dicationic benzothiazole compound (9a) exhibited sub-nanomolar in vitro potency with remarkable selectivity over mammalian cells (>26,000-fold). Unsubstituted 5-amidine groups and a cyclohexyl spacer were the crucial determinants of trypanocidal activity. In all cases, mice treated with a single dose of 20 mg kg-1 were cured of stage 1 trypanosomiasis. The compound displayed a favorable in vitro ADME profile, with the exception of low membrane permeability. However, we found evidence that uptake by T. brucei is mediated by endocytosis, a process that results in lysosomal sequestration. The compound was also active in low nanomolar concentrations against cultured asexual forms of the malaria parasite Plasmodium falciparum. Therefore, 9a has exquisite cross-species efficacy and represents a lead compound with considerable therapeutic potential.
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Affiliation(s)
- Livio Racané
- Department
of Applied Chemistry, Faculty of Textile Technology, University of Zagreb, Prilaz baruna Filipovića 28a, 10000 Zagreb, Croatia
| | - Lucija Ptiček
- Department
of Applied Chemistry, Faculty of Textile Technology, University of Zagreb, Prilaz baruna Filipovića 28a, 10000 Zagreb, Croatia
| | - Sanja Kostrun
- Chemistry
Department, Selvita Ltd., Prilaz baruna Filipovića 29, 10000 Zagreb, Croatia
| | - Silvana Raić-Malić
- Department
of Organic Chemistry, Faculty of Chemical Engineering and Technology, University of Zagreb, Marulićev trg 20, 10000 Zagreb, Croatia
| | - Martin Craig Taylor
- Department
of Infection Biology, London School of Hygiene
and Tropical Medicine, Keppel Street, WC1E 7HT London, U.K.
| | - Michael Delves
- Department
of Infection Biology, London School of Hygiene
and Tropical Medicine, Keppel Street, WC1E 7HT London, U.K.
| | - Sam Alsford
- Department
of Infection Biology, London School of Hygiene
and Tropical Medicine, Keppel Street, WC1E 7HT London, U.K.
| | - Francisco Olmo
- Department
of Infection Biology, London School of Hygiene
and Tropical Medicine, Keppel Street, WC1E 7HT London, U.K.
| | - Amanda Fortes Francisco
- Department
of Infection Biology, London School of Hygiene
and Tropical Medicine, Keppel Street, WC1E 7HT London, U.K.
| | - John M. Kelly
- Department
of Infection Biology, London School of Hygiene
and Tropical Medicine, Keppel Street, WC1E 7HT London, U.K.
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3
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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] [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.
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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,
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4
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Gilabert Carbajo C, Cornell LJ, Madbouly Y, Lai Z, Yates PA, Tinti M, Tiengwe C. Novel aspects of iron homeostasis in pathogenic bloodstream form Trypanosoma brucei. PLoS Pathog 2021; 17:e1009696. [PMID: 34161395 PMCID: PMC8259959 DOI: 10.1371/journal.ppat.1009696] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/28/2021] [Revised: 07/06/2021] [Accepted: 06/04/2021] [Indexed: 01/09/2023] Open
Abstract
Iron is an essential regulatory signal for virulence factors in many pathogens. Mammals and bloodstream form (BSF) Trypanosoma brucei obtain iron by receptor-mediated endocytosis of transferrin bound to receptors (TfR) but the mechanisms by which T. brucei subsequently handles iron remains enigmatic. Here, we analyse the transcriptome of T. brucei cultured in iron-rich and iron-poor conditions. We show that adaptation to iron-deprivation induces upregulation of TfR, a cohort of parasite-specific genes (ESAG3, PAGS), genes involved in glucose uptake and glycolysis (THT1 and hexokinase), endocytosis (Phosphatidic Acid Phosphatase, PAP2), and most notably a divergent RNA binding protein RBP5, indicative of a non-canonical mechanism for regulating intracellular iron levels. We show that cells depleted of TfR by RNA silencing import free iron as a compensatory survival strategy. The TfR and RBP5 iron response are reversible by genetic complementation, the response kinetics are similar, but the regulatory mechanisms are distinct. Increased TfR protein is due to increased mRNA. Increased RBP5 expression, however, occurs by a post-transcriptional feedback mechanism whereby RBP5 interacts with its own, and with PAP2 mRNAs. Further observations suggest that increased RBP5 expression in iron-deprived cells has a maximum threshold as ectopic overexpression above this threshold disrupts normal cell cycle progression resulting in an accumulation of anucleate cells and cells in G2/M phase. This phenotype is not observed with overexpression of RPB5 containing a point mutation (F61A) in its single RNA Recognition Motif. Our experiments shed new light on how T. brucei BSFs reorganise their transcriptome to deal with iron stress revealing the first iron responsive RNA binding protein that is co-regulated with TfR, is important for cell viability and iron homeostasis; two essential processes for successful proliferation.
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Affiliation(s)
- Carla Gilabert Carbajo
- Department of Life Sciences, Sir Ernst Chain Building, Imperial College London, London, United Kingdom
| | - Lucy J. Cornell
- Department of Life Sciences, Sir Ernst Chain Building, Imperial College London, London, United Kingdom
| | - Youssef Madbouly
- Department of Life Sciences, Sir Ernst Chain Building, Imperial College London, London, United Kingdom
| | - Zhihao Lai
- Department of Life Sciences, Sir Ernst Chain Building, Imperial College London, London, United Kingdom
| | - Phillip A. Yates
- Department of Chemical Physiology and Biochemistry, Oregon Health and Science University, Portland, Oregon, United States of America
| | - Michele Tinti
- Wellcome Trust Centre for Anti-Infectives Research, School of Life Sciences, University of Dundee, Dundee, United Kingdom
| | - Calvin Tiengwe
- Department of Life Sciences, Sir Ernst Chain Building, Imperial College London, London, United Kingdom
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5
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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] [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.
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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
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6
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Mach J, Sutak R. Iron in parasitic protists – from uptake to storage and where we can interfere. Metallomics 2020; 12:1335-1347. [DOI: 10.1039/d0mt00125b] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/11/2022]
Abstract
A comprehensive review of iron metabolism in parasitic protists and its potential use as a drug target.
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Affiliation(s)
- Jan Mach
- Department of Parasitology
- Faculty of Science - BIOCEV
- Charles University
- Vestec u Prahy
- Czech Republic
| | - Robert Sutak
- Department of Parasitology
- Faculty of Science - BIOCEV
- Charles University
- Vestec u Prahy
- Czech Republic
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7
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Kariuki CK, Stijlemans B, Magez S. The Trypanosomal Transferrin Receptor of Trypanosoma Brucei-A Review. Trop Med Infect Dis 2019; 4:tropicalmed4040126. [PMID: 31581506 PMCID: PMC6958415 DOI: 10.3390/tropicalmed4040126] [Citation(s) in RCA: 10] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/09/2019] [Revised: 09/19/2019] [Accepted: 09/25/2019] [Indexed: 02/06/2023] Open
Abstract
Iron is an essential element for life. Its uptake and utility requires a careful balancing with its toxic capacity, with mammals evolving a safe and bio-viable means of its transport and storage. This transport and storage is also utilized as part of the iron-sequestration arsenal employed by the mammalian hosts’ ‘nutritional immunity’ against parasites. Interestingly, a key element of iron transport, i.e., serum transferrin (Tf), is an essential growth factor for parasitic haemo-protozoans of the genus Trypanosoma. These are major mammalian parasites causing the diseases human African trypanosomosis (HAT) and animal trypanosomosis (AT). Using components of their well-characterized immune evasion system, bloodstream Trypanosoma brucei parasites adapt and scavenge for the mammalian host serum transferrin within their broad host range. The expression site associated genes (ESAG6 and 7) are utilized to construct a heterodimeric serum Tf binding complex which, within its niche in the flagellar pocket, and coupled to the trypanosomes’ fast endocytic rate, allows receptor-mediated acquisition of essential iron from their environment. This review summarizes current knowledge of the trypanosomal transferrin receptor (TfR), with emphasis on the structure and function of the receptor, both in physiological conditions as well as in conditions where the iron supply to parasites is being limited. Potential applications using current knowledge of the parasite receptor are also briefly discussed, primarily focused on potential therapeutic interventions.
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Affiliation(s)
- Christopher K. Kariuki
- Laboratory of Cellular and Molecular Interactions (CMIM), Vrije Universiteit Brussels, Brussels, 1050 Ixelles, Belgium;
- Department of Tropical and Infectious Diseases, Institute of Primate Research (IPR), 00502 Nairobi, Kenya
- Correspondence: (C.K.K.); (S.M.); Tel.: +322-629-1975 (C.K.K.); +82-32626-4207 (S.M.)
| | - Benoit Stijlemans
- Laboratory of Cellular and Molecular Interactions (CMIM), Vrije Universiteit Brussels, Brussels, 1050 Ixelles, Belgium;
- Myeloid Cell Immunology Lab, VIB Center for Inflammation Research, Brussels, 9052 Gent, Belgium
| | - Stefan Magez
- Laboratory of Cellular and Molecular Interactions (CMIM), Vrije Universiteit Brussels, Brussels, 1050 Ixelles, Belgium;
- Laboratory for Biomedical Research, Ghent University Global Campus, Yeonsu-Gu, Incheon 219220, Korea
- Correspondence: (C.K.K.); (S.M.); Tel.: +322-629-1975 (C.K.K.); +82-32626-4207 (S.M.)
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8
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Zheng F, Colasante C, Voncken F. Characterisation of a mitochondrial iron transporter of the pathogen Trypanosoma brucei. Mol Biochem Parasitol 2019; 233:111221. [DOI: 10.1016/j.molbiopara.2019.111221] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/12/2019] [Revised: 09/10/2019] [Accepted: 09/13/2019] [Indexed: 12/25/2022]
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9
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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] [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.
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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 .
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10
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Bais S, Greenberg RM. TRP channels as potential targets for antischistosomals. Int J Parasitol Drugs Drug Resist 2018; 8:511-517. [PMID: 30224169 PMCID: PMC6287577 DOI: 10.1016/j.ijpddr.2018.08.003] [Citation(s) in RCA: 14] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/16/2018] [Revised: 08/23/2018] [Accepted: 08/28/2018] [Indexed: 01/08/2023]
Abstract
Ion channels are membrane protein complexes that underlie electrical excitability in cells, allowing ions to diffuse through cell membranes in a regulated fashion. They are essential for normal functioning of the neuromusculature and other tissues. Ion channels are also validated targets for many current anthelmintics, yet the properties of only a small subset of ion channels in parasitic helminths have been explored in any detail. Transient receptor potential (TRP) channels comprise a widely diverse superfamily of ion channels with important roles in sensory signaling, regulation of ion homeostasis, organellar trafficking, and other functions. There are several subtypes of TRP channels, including TRPA1 and TRPV1 channels, both of which are involved in, among other functions, sensory, nociceptive, and inflammatory signaling in mammals. Several lines of evidence indicate that TRPA1-like channels in schistosomes exhibit pharmacological sensitivities that differ from their mammalian counterparts and that may signify unique physiological properties as well. Thus, in addition to responding to TRPA1 modulators, schistosome TRPA1-like channels also respond to compounds that in other organisms modulate TRPV1 channels. Notably, TRPV channel genes are not found in schistosome genomes. Here, we review the evidence leading to these conclusions and examine potential implications. We also discuss recent results showing that praziquantel, the current drug of choice against schistosomiasis, selectively targets host TRP channels in addition to its likely primary targets in the parasite. The results we discuss add weight to the notion that schistosome TRP channels are worthy of investigation as candidate therapeutic targets.
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Affiliation(s)
- Swarna Bais
- Department of Pathobiology, School of Veterinary Medicine, University of Pennsylvania, 3800 Spruce Street, Philadelphia PA 19104, USA
| | - Robert M Greenberg
- Department of Pathobiology, School of Veterinary Medicine, University of Pennsylvania, 3800 Spruce Street, Philadelphia PA 19104, USA.
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11
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Tonini ML, Peña-Diaz P, Haindrich AC, Basu S, Kriegová E, Pierik AJ, Lill R, MacNeill SA, Smith TK, Lukeš J. Branched late-steps of the cytosolic iron-sulphur cluster assembly machinery of Trypanosoma brucei. PLoS Pathog 2018; 14:e1007326. [PMID: 30346997 PMCID: PMC6211773 DOI: 10.1371/journal.ppat.1007326] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/17/2017] [Revised: 11/01/2018] [Accepted: 09/10/2018] [Indexed: 02/07/2023] Open
Abstract
Fe-S clusters are ubiquitous cofactors of proteins involved in a variety of essential cellular processes. The biogenesis of Fe-S clusters in the cytosol and their insertion into proteins is accomplished through the cytosolic iron-sulphur protein assembly (CIA) machinery. The early- and middle-acting modules of the CIA pathway concerned with the assembly and trafficking of Fe-S clusters have been previously characterised in the parasitic protist Trypanosoma brucei. In this study, we applied proteomic and genetic approaches to gain insights into the network of protein-protein interactions of the late-acting CIA targeting complex in T. brucei. All components of the canonical CIA machinery are present in T. brucei including, as in humans, two distinct CIA2 homologues TbCIA2A and TbCIA2B. These two proteins are found interacting with TbCIA1, yet the interaction is mutually exclusive, as determined by mass spectrometry. Ablation of most of the components of the CIA targeting complex by RNAi led to impaired cell growth in vitro, with the exception of TbCIA2A in procyclic form (PCF) trypanosomes. Depletion of the CIA-targeting complex was accompanied by reduced levels of protein-bound cytosolic iron and decreased activity of an Fe-S dependent enzyme in PCF trypanosomes. We demonstrate that the C-terminal domain of TbMMS19 acts as a docking site for TbCIA2B and TbCIA1, forming a trimeric complex that also interacts with target Fe-S apo-proteins and the middle-acting CIA component TbNAR1. Cytosolic and nuclear proteins containing iron-sulphur clusters (Fe-S) are essential for the survival of every extant eukaryotic cell. The biogenesis of Fe-S clusters and their insertion into proteins is accomplished through the cytosolic iron-sulphur protein assembly (CIA) machinery. Recently, the CIA factors that generate cytosolic Fe-S clusters were characterised in T. brucei, a unicellular parasite that causes diseases in humans and animals. However, an outstanding question in this organism is the way by which the CIA machinery directs and inserts newly formed Fe-S clusters into proteins. We found that the T. brucei proteins TbCIA2B and TbCIA1 assemble at a region of the C-terminal domain of a third protein, TbMMS19, to form a complex labelled the CIA targeting complex (CTC). The CTC interacts with TbNAR1 and with Fe-S proteins, meaning that the complex assists in the transfer of Fe-S clusters from the upstream members of the pathway into target Fe-S proteins. T. brucei cells depleted of CTC had decreased levels of protein-bound cytosolic iron, and lower activities of cytosolic aconitase, an enzyme that depends upon Fe-S clusters to function.
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Affiliation(s)
- Maiko Luis Tonini
- Biomedical Sciences Research Complex (BSRC), University of St Andrews, St Andrews, Fife, United Kingdom
| | - Priscila Peña-Diaz
- Biology Centre, Institute of Parasitology, Czech Academy of Sciences, České Budějovice (Budweis), Czech Republic
| | - Alexander C. Haindrich
- Biology Centre, Institute of Parasitology, Czech Academy of Sciences, České Budějovice (Budweis), Czech Republic
- Faculty of Sciences, University of South Bohemia, České Budějovice (Budweis), Czech Republic
| | - Somsuvro Basu
- Biology Centre, Institute of Parasitology, Czech Academy of Sciences, České Budějovice (Budweis), Czech Republic
- Institut für Zytobiologie, Philipps-Universität Marburg, Marburg, Germany
| | - Eva Kriegová
- Biology Centre, Institute of Parasitology, Czech Academy of Sciences, České Budějovice (Budweis), Czech Republic
| | - Antonio J. Pierik
- Faculty of Chemistry–Biochemistry, University of Kaiserslautern, Kaiserslautern, Germany
| | - Roland Lill
- Institut für Zytobiologie, Philipps-Universität Marburg, Marburg, Germany
- LOEWE Zentrum für synthetische Mikrobiologie, Marburg, Germany
| | - Stuart A. MacNeill
- Biomedical Sciences Research Complex (BSRC), University of St Andrews, St Andrews, Fife, United Kingdom
- * E-mail: (SAM); (TKS); (JL)
| | - Terry K. Smith
- Biomedical Sciences Research Complex (BSRC), University of St Andrews, St Andrews, Fife, United Kingdom
- * E-mail: (SAM); (TKS); (JL)
| | - Julius Lukeš
- Biology Centre, Institute of Parasitology, Czech Academy of Sciences, České Budějovice (Budweis), Czech Republic
- Faculty of Sciences, University of South Bohemia, České Budějovice (Budweis), Czech Republic
- * E-mail: (SAM); (TKS); (JL)
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12
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Quintana JF, Pino RCD, Yamada K, Zhang N. Adaptation and Therapeutic Exploitation of the Plasma Membrane of African Trypanosomes. Genes (Basel) 2018; 9:E368. [PMID: 30037058 PMCID: PMC6071061 DOI: 10.3390/genes9070368] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/24/2018] [Revised: 07/18/2018] [Accepted: 07/19/2018] [Indexed: 12/19/2022] Open
Abstract
African trypanosomes are highly divergent from their metazoan hosts, and as part of adaptation to a parasitic life style have developed a unique endomembrane system. The key virulence mechanism of many pathogens is successful immune evasion, to enable survival within a host, a feature that requires both genetic events and membrane transport mechanisms in African trypanosomes. Intracellular trafficking not only plays a role in immune evasion, but also in homeostasis of intracellular and extracellular compartments and interactions with the environment. Significantly, historical and recent work has unraveled some of the connections between these processes and highlighted how immune evasion mechanisms that are associated with adaptations to membrane trafficking may have, paradoxically, provided specific sensitivity to drugs. Here, we explore these advances in understanding the membrane composition of the trypanosome plasma membrane and organelles and provide a perspective for how transport could be exploited for therapeutic purposes.
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Affiliation(s)
- Juan F Quintana
- School of Life Sciences, University of Dundee, Dow Street, Dundee, DD1 5EH, UK.
| | | | - Kayo Yamada
- School of Life Sciences, University of Dundee, Dow Street, Dundee, DD1 5EH, UK.
| | - Ning Zhang
- School of Life Sciences, University of Dundee, Dow Street, Dundee, DD1 5EH, UK.
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13
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Ramakrishnan S, Docampo R. Membrane Proteins in Trypanosomatids Involved in Ca 2+ Homeostasis and Signaling. Genes (Basel) 2018; 9:E304. [PMID: 29921754 PMCID: PMC6027440 DOI: 10.3390/genes9060304] [Citation(s) in RCA: 20] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/31/2018] [Revised: 06/11/2018] [Accepted: 06/14/2018] [Indexed: 01/10/2023] Open
Abstract
Calcium ion (Ca2+) serves as a second messenger for a variety of cell functions in trypanosomes. Several proteins in the plasma membrane, acidocalcisomes, endoplasmic reticulum, and mitochondria are involved in its homeostasis and in cell signaling roles. The plasma membrane has a Ca2+ channel for its uptake and a plasma membrane-type Ca2+-ATPase (PMCA) for its efflux. A similar PMCA is also located in acidocalcisomes, acidic organelles that are the primary Ca2+ store and that possess an inositol 1,4,5-trisphosphate receptor (IP₃R) for Ca2+ efflux. Their mitochondria possess a mitochondrial calcium uniporter complex (MCUC) for Ca2+ uptake and a Ca2+/H⁺ exchanger for Ca2+ release. The endoplasmic reticulum has a sarcoplasmic-endoplasmic reticulum-type Ca2+-ATPase (SERCA) for Ca2+ uptake but no Ca2+ release mechanism has been identified. Additionally, the trypanosomatid genomes contain other membrane proteins that could potentially bind calcium and await further characterization.
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Affiliation(s)
- Srinivasan Ramakrishnan
- Center for Tropical and Emerging Global Diseases, University of Georgia, Athens, GA 30602, USA.
| | - Roberto Docampo
- Center for Tropical and Emerging Global Diseases, University of Georgia, Athens, GA 30602, USA.
- Department of Cellular Biology and Center for Tropical and Emerging Global Diseases, University of Georgia, Athens, GA 30602, USA.
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14
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Cruz-Bustos T, Moreno SNJ, Docampo R. Detection of Weakly Expressed Trypanosoma cruzi Membrane Proteins Using High-Performance Probes. J Eukaryot Microbiol 2018. [PMID: 29542839 DOI: 10.1111/jeu.12517] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/28/2022]
Abstract
Membrane proteins in trypanosomatids are, in general, weakly expressed and confirmation of their subcellular localization frequently requires their overexpression with epitope tags. However, overexpression can lead to mislocalization of the probes. Viswanathan et al. (Nat. Methods, 2015, 12:568) described high performance tags for localization of weakly expressed proteins. We report here the use of these protein tags, named "spaghetti monster," for CRISPR/Cas9-mediated C-terminal endogenous tagging of Trypanosoma cruzi to localize two weakly expressed transient receptor potential channels to acidic compartments. The results indicate that this method will improve the detection of membrane proteins in T. cruzi.
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Affiliation(s)
- Teresa Cruz-Bustos
- Center for Tropical and Emerging Global Diseases, University of Georgia, Athens, Georgia, 30602
| | - Silvia N J Moreno
- Center for Tropical and Emerging Global Diseases, University of Georgia, Athens, Georgia, 30602.,Department of Cellular Biology, University of Georgia, Athens, Georgia, 30602
| | - Roberto Docampo
- Center for Tropical and Emerging Global Diseases, University of Georgia, Athens, Georgia, 30602.,Department of Cellular Biology, University of Georgia, Athens, Georgia, 30602
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15
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Franco J, Medeiros A, Benítez D, Perelmuter K, Serra G, Comini MA, Scarone L. In vitro activity and mode of action of distamycin analogues against African trypanosomes. Eur J Med Chem 2016; 126:776-788. [PMID: 27951486 DOI: 10.1016/j.ejmech.2016.12.002] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/17/2016] [Revised: 10/29/2016] [Accepted: 12/01/2016] [Indexed: 12/14/2022]
Abstract
Distamycin, a natural polyamide containing three heterocycle rings with a polar end, has inspired several groups to prepare synthetic analogues, which proved to have anti-trypanosomal and anti-tumoral activity. We describe the synthesis of bi and tri thiazoles amides that harbor different substitutions at their ends and the evaluation of their anti-Trypanosoma brucei activity. The most active compound 10b showed better biological activity (EC50 310 nM and selectivity index 16) than the control drug nifurtimox (EC50 15 μM and selectivity index 10). Studies on the mode of action show that the parasiticidal activity of 10b originates from disruption of lysosomal homeostasis, which is followed by release of redox active iron, an increase in oxidizing species and collapse of cell membrane integrity. In this respect, our study suggests that non-charged lipophylic distamycins destabilize cell membranes.
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Affiliation(s)
- Jaime Franco
- Laboratorio de Química Farmacéutica, Departamento de Química Orgánica, Facultad de Química, Universidad de la República, Montevideo, Uruguay; Group Redox Biology of Trypanosomes, Institut Pasteur de Montevideo, Montevideo, Uruguay
| | - Andrea Medeiros
- Group Redox Biology of Trypanosomes, Institut Pasteur de Montevideo, Montevideo, Uruguay; Departamento de Bioquímica, Facultad de Medicina, Universidad de la República, Montevideo, Uruguay
| | - Diego Benítez
- Group Redox Biology of Trypanosomes, Institut Pasteur de Montevideo, Montevideo, Uruguay
| | - Karen Perelmuter
- Cell Biology Unit, Institut Pasteur de Montevideo, Montevideo, Uruguay
| | - Gloria Serra
- Laboratorio de Química Farmacéutica, Departamento de Química Orgánica, Facultad de Química, Universidad de la República, Montevideo, Uruguay
| | - Marcelo A Comini
- Group Redox Biology of Trypanosomes, Institut Pasteur de Montevideo, Montevideo, Uruguay.
| | - Laura Scarone
- Laboratorio de Química Farmacéutica, Departamento de Química Orgánica, Facultad de Química, Universidad de la República, Montevideo, Uruguay.
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16
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Bais S, Greenberg RM. TRP channels in schistosomes. INTERNATIONAL JOURNAL FOR PARASITOLOGY-DRUGS AND DRUG RESISTANCE 2016; 6:335-342. [PMID: 27496302 PMCID: PMC5196486 DOI: 10.1016/j.ijpddr.2016.07.002] [Citation(s) in RCA: 24] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 05/12/2016] [Revised: 07/13/2016] [Accepted: 07/17/2016] [Indexed: 12/22/2022]
Abstract
Praziquantel (PZQ) is effectively the only drug currently available for treatment and control of schistosomiasis, a disease affecting hundreds of millions of people worldwide. Many anthelmintics, likely including PZQ, target ion channels, membrane protein complexes essential for normal functioning of the neuromusculature and other tissues. Despite this fact, only a few classes of parasitic helminth ion channels have been assessed for their pharmacological properties or for their roles in parasite physiology. One such overlooked group of ion channels is the transient receptor potential (TRP) channel superfamily. TRP channels share a common core structure, but are widely diverse in their activation mechanisms and ion selectivity. They are critical to transducing sensory signals, responding to a wide range of external stimuli. They are also involved in other functions, such as regulating intracellular calcium and organellar ion homeostasis and trafficking. Here, we review current literature on parasitic helminth TRP channels, focusing on those in schistosomes. We discuss the likely roles of these channels in sensory and locomotor activity, including the possible significance of a class of TRP channels (TRPV) that is absent in schistosomes. We also focus on evidence indicating that at least one schistosome TRP channel (SmTRPA) has atypical, TRPV1-like pharmacological sensitivities that could potentially be exploited for future therapeutic targeting. We provide an overview of transient receptor potential (TRP) channels in schistosomes and other parasitic helminths. TRP channels are important for sensory signaling, ion homeostasis, organellar trafficking, and a host of other functions. Very little work has been done on TRP channels in parasitic helminths. TRPV channels, found throughout the Metazoa, appear not to be present in parasitic platyhelminths. TRP channels in schistosomes appear to have atypical pharmacology, perhaps an entrée for therapeutic targeting.
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Affiliation(s)
- Swarna Bais
- Department of Pathobiology, School of Veterinary Medicine, University of Pennsylvania, 3800 Spruce Street, Philadelphia, PA 19104, USA
| | - Robert M Greenberg
- Department of Pathobiology, School of Veterinary Medicine, University of Pennsylvania, 3800 Spruce Street, Philadelphia, PA 19104, USA.
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17
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Basu S, Horáková E, Lukeš J. Iron-associated biology of Trypanosoma brucei. Biochim Biophys Acta Gen Subj 2015; 1860:363-70. [PMID: 26523873 DOI: 10.1016/j.bbagen.2015.10.027] [Citation(s) in RCA: 16] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/31/2015] [Revised: 10/22/2015] [Accepted: 10/29/2015] [Indexed: 01/28/2023]
Abstract
BACKGROUND Every eukaryote requires iron, which is also true for the parasitic protist Trypanosoma brucei, the causative agent of sleeping sickness in humans and nagana in cattle. T. brucei undergoes a complex life cycle during which its single mitochondrion is subject to major metabolic and morphological changes. SCOPE OF REVIEW This review covers what is known about processes associated with iron-sulfur clusters and heme metabolism in T. brucei. We discuss strategies by which iron and heme are acquired and utilized by this model parasite, emphasizing the differences between its two life cycle stages residing in the bloodstream of the mammalian host and gut of the insect vector. Finally, the role of iron in the host-parasite interactions is discussed along with their possible exploitation in fighting these deadly parasites. MAJOR CONCLUSIONS The processes associated with acquisition and utilization of iron, distinct in the two life stages of T. brucei, are fine tuned for the dramatically different host environment occupied by them. Although the composition and compartmentalization of the iron-sulfur cluster assembly seem to be conserved, some unique features of the iron acquisition strategies may be exploited for medical interventions against these parasites. GENERAL SIGNIFICANCE As early-branching protists, trypanosomes and related flagellates are known to harbor an array of unique features, with the acquisition of iron being another peculiarity. Thanks to intense research within the last decade, understanding of iron-sulfur cluster assembly and iron metabolism in T. brucei is among the most advanced of all eukaryotes.
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Affiliation(s)
- Somsuvro Basu
- Biology Centre, Institute of Parasitology, Czech Academy of Sciences, 37005 České Budějovice (Budweis), Czech Republic; Institut für Zytobiologie, Philipps-Universität Marburg, 35032 Marburg, Germany
| | - Eva Horáková
- Biology Centre, Institute of Parasitology, Czech Academy of Sciences, 37005 České Budějovice (Budweis), Czech Republic
| | - Julius Lukeš
- Biology Centre, Institute of Parasitology, Czech Academy of Sciences, 37005 České Budějovice (Budweis), Czech Republic; Faculty of Science, University of South Bohemia, 37005 České Budějovice (Budweis), Czech Republic; Canadian Institute for Advanced Research, Toronto, Canada.
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18
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Iron Homeostasis and Trypanosoma brucei Associated Immunopathogenicity Development: A Battle/Quest for Iron. BIOMED RESEARCH INTERNATIONAL 2015; 2015:819389. [PMID: 26090446 PMCID: PMC4450282 DOI: 10.1155/2015/819389] [Citation(s) in RCA: 18] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 10/07/2014] [Revised: 02/11/2015] [Accepted: 02/15/2015] [Indexed: 12/24/2022]
Abstract
African trypanosomosis is a chronic debilitating disease affecting the health and economic well-being of developing countries. The immune response during African trypanosome infection consisting of a strong proinflammatory M1-type activation of the myeloid phagocyte system (MYPS) results in iron deprivation for these extracellular parasites. Yet, the persistence of M1-type MYPS activation causes the development of anemia (anemia of chronic disease, ACD) as a most prominent pathological parameter in the mammalian host, due to enhanced erythrophagocytosis and retention of iron within the MYPS thereby depriving iron for erythropoiesis. In this review we give an overview of how parasites acquire iron from the host and how iron modulation of the host MYPS affects trypanosomosis-associated anemia development. Finally, we also discuss different strategies at the level of both the host and the parasite that can/might be used to modulate iron availability during African trypanosome infections.
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19
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Docampo R, Huang G. Calcium signaling in trypanosomatid parasites. Cell Calcium 2014; 57:194-202. [PMID: 25468729 DOI: 10.1016/j.ceca.2014.10.015] [Citation(s) in RCA: 49] [Impact Index Per Article: 4.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/24/2014] [Revised: 10/27/2014] [Accepted: 10/29/2014] [Indexed: 11/29/2022]
Abstract
Calcium ion (Ca(2+)) is an important second messenger in trypanosomatids and essential for their survival although prolonged high intracellular Ca(2+) levels lead to cell death. As other eukaryotic cells, trypanosomes use two sources of Ca(2+) for generating signals: Ca(2+) release from intracellular stores and Ca(2+) entry across the plasma membrane. Ca(2+) release from intracellular stores is controlled by the inositol 1,4,5-trisphosphate receptor (IP3R) that is located in acidocalcisomes, acidic organelles that are the primary Ca(2+) reservoir in these cells. A plasma membrane Ca(2+)-ATPase controls the cytosolic Ca(2+) levels and a number of pumps and exchangers are responsible for Ca(2+) uptake and release from intracellular compartments. The trypanosomatid genomes contain a wide variety of signaling and regulatory proteins that bind Ca(2+) as well as many Ca(2+)-binding proteins that await further characterization. The mitochondrial Ca(2+) transporters of trypanosomatids have an important role in the regulation of cell bioenergetics and flagellar Ca(2+) appears to have roles in sensing the environment. In trypanosomatids in which an intracellular life cycle is present, Ca(2+) signaling is important for host cell invasion.
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Affiliation(s)
- Roberto Docampo
- Center for Tropical and Emerging Global Diseases and Department of Cellular Biology, University of Georgia, Athens, GA 30620, USA; Departamento de Patologia Clínica, State University of Campinas, Campinas, SP 13083, Brazil.
| | - Guozhong Huang
- Center for Tropical and Emerging Global Diseases and Department of Cellular Biology, University of Georgia, Athens, GA 30620, USA
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20
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Hiller C, Nissen A, Benítez D, Comini MA, Krauth-Siegel RL. Cytosolic peroxidases protect the lysosome of bloodstream African trypanosomes from iron-mediated membrane damage. PLoS Pathog 2014; 10:e1004075. [PMID: 24722489 PMCID: PMC3983053 DOI: 10.1371/journal.ppat.1004075] [Citation(s) in RCA: 19] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/05/2013] [Accepted: 03/02/2014] [Indexed: 01/23/2023] Open
Abstract
African trypanosomes express three virtually identical non-selenium glutathione peroxidase (Px)-type enzymes which preferably detoxify lipid-derived hydroperoxides. As shown previously, bloodstream Trypanosoma brucei lacking the mitochondrial Px III display only a weak and transient proliferation defect whereas parasites that lack the cytosolic Px I and Px II undergo extremely fast lipid peroxidation and cell lysis. The phenotype can completely be rescued by supplementing the medium with the α-tocopherol derivative Trolox. The mechanism underlying the rapid cell death remained however elusive. Here we show that the lysosome is the origin of the cellular injury. Feeding the px I–II knockout parasites with Alexa Fluor-conjugated dextran or LysoTracker in the presence of Trolox yielded a discrete lysosomal staining. Yet upon withdrawal of the antioxidant, the signal became progressively spread over the whole cell body and was completely lost, respectively. T. brucei acquire iron by endocytosis of host transferrin. Supplementing the medium with iron or transferrin induced, whereas the iron chelator deferoxamine and apo-transferrin attenuated lysis of the px I–II knockout cells. Immunofluorescence microscopy with MitoTracker and antibodies against the lysosomal marker protein p67 revealed that disintegration of the lysosome precedes mitochondrial damage. In vivo experiments confirmed the negligible role of the mitochondrial peroxidase: Mice infected with px III knockout cells displayed only a slightly delayed disease development compared to wild-type parasites. Our data demonstrate that in bloodstream African trypanosomes, the lysosome, not the mitochondrion, is the primary site of oxidative damage and cytosolic trypanothione/tryparedoxin-dependent peroxidases protect the lysosome from iron-induced membrane peroxidation. This process appears to be closely linked to the high endocytic rate and distinct iron acquisition mechanisms of the infective stage of T. brucei. The respective knockout of the cytosolic px I–II in the procyclic insect form resulted in cells that were fully viable in Trolox-free medium. In many cell types, mitochondria are the main source of intracellular reactive oxygen species but iron-induced oxidative lysosomal damage has been described as well. African trypanosomes are the causative agents of human sleeping sickness and the cattle disease Nagana. The parasites are obligate extracellular pathogens that multiply in the bloodstream and body fluids of their mammalian hosts and as procyclic forms in their insect vector, the tsetse fly. Bloodstream Trypanosoma brucei in which the genes for cytosolic lipid hydroperoxide-detoxifying peroxidases have been knocked out undergo an extremely rapid membrane peroxidation and lyse within less than two hours when they are cultured without an exogenous antioxidant. Here we show that the primary site of intracellular damage is the single terminal lysosome of the parasites. Disintegration of the lysosome clearly precedes damage of the mitochondrion and parasite death. Iron, acquired by the endocytosis of iron-loaded host transferrin, induces cell lysis. Contrary to the cytosolic enzymes, the respective mitochondrial peroxidase is dispensable for both in vitro proliferation and mouse infectivity. This is the first report demonstrating that cytosolic thiol peroxidases are responsible for protecting the lysosome of a cell.
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Affiliation(s)
- Corinna Hiller
- Biochemie-Zentrum der Universität Heidelberg (BZH), Heidelberg, Germany
| | - Amrei Nissen
- Biochemie-Zentrum der Universität Heidelberg (BZH), Heidelberg, Germany
| | - Diego Benítez
- Group Redox Biology of Trypanosomes, Institut Pasteur de Montevideo, Montevideo, Uruguay
| | - Marcelo A. Comini
- Group Redox Biology of Trypanosomes, Institut Pasteur de Montevideo, Montevideo, Uruguay
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