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Nedvědová Š, De Stefano D, Walker O, Hologne M, Miele AE. Revisiting Schistosoma mansoni Micro-Exon Gene (MEG) Protein Family: A Tour into Conserved Motifs and Annotation. Biomolecules 2023; 13:1275. [PMID: 37759676 PMCID: PMC10526429 DOI: 10.3390/biom13091275] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/20/2023] [Revised: 08/15/2023] [Accepted: 08/18/2023] [Indexed: 09/29/2023] Open
Abstract
Genome sequencing of the human parasite Schistosoma mansoni revealed an interesting gene superfamily, called micro-exon gene (meg), that encodes secreted MEG proteins. The genes are composed of short exons (3-81 base pairs) regularly interspersed with long introns (up to 5 kbp). This article recollects 35 S. mansoni specific meg genes that are distributed over 7 autosomes and one pair of sex chromosomes and that code for at least 87 verified MEG proteins. We used various bioinformatics tools to produce an optimal alignment and propose a phylogenetic analysis. This work highlighted intriguing conserved patterns/motifs in the sequences of the highly variable MEG proteins. Based on the analyses, we were able to classify the verified MEG proteins into two subfamilies and to hypothesize their duplication and colonization of all the chromosomes. Together with motif identification, we also proposed to revisit MEGs' common names and annotation in order to avoid duplication, to help the reproducibility of research results and to avoid possible misunderstandings.
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Affiliation(s)
- Štěpánka Nedvědová
- UMR 5280 Institute of Analytical Sciences, Université de Lyon, CNRS, Université Claude Bernard Lyon 1, 69100 Villeurbanne, France; (Š.N.); (O.W.); (M.H.)
- Department of Chemistry, Faculty of Agrobiology, Food and Natural Resources, Czech University of Life Sciences, 16500 Prague, Czech Republic
- Department of Zoology and Fisheries, Center of Infectious Animal Diseases, Czech University of Life Sciences, 16500 Prague, Czech Republic
| | - Davide De Stefano
- UMR 5280 Institute of Analytical Sciences, Université de Lyon, CNRS, Université Claude Bernard Lyon 1, 69100 Villeurbanne, France; (Š.N.); (O.W.); (M.H.)
| | - Olivier Walker
- UMR 5280 Institute of Analytical Sciences, Université de Lyon, CNRS, Université Claude Bernard Lyon 1, 69100 Villeurbanne, France; (Š.N.); (O.W.); (M.H.)
| | - Maggy Hologne
- UMR 5280 Institute of Analytical Sciences, Université de Lyon, CNRS, Université Claude Bernard Lyon 1, 69100 Villeurbanne, France; (Š.N.); (O.W.); (M.H.)
| | - Adriana Erica Miele
- UMR 5280 Institute of Analytical Sciences, Université de Lyon, CNRS, Université Claude Bernard Lyon 1, 69100 Villeurbanne, France; (Š.N.); (O.W.); (M.H.)
- Department of Biochemical Sciences, Sapienza University of Rome, 00185 Rome, Italy
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2
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Safi R, Sánchez-Álvarez M, Bosch M, Demangel C, Parton RG, Pol A. Defensive-lipid droplets: Cellular organelles designed for antimicrobial immunity. Immunol Rev 2023; 317:113-136. [PMID: 36960679 DOI: 10.1111/imr.13199] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 03/25/2023]
Abstract
Microbes have developed many strategies to subvert host organisms, which, in turn, evolved several innate immune responses. As major lipid storage organelles of eukaryotes, lipid droplets (LDs) are an attractive source of nutrients for invaders. Intracellular viruses, bacteria, and protozoan parasites induce and physically interact with LDs, and the current view is that they "hijack" LDs to draw on substrates for host colonization. This dogma has been challenged by the recent demonstration that LDs are endowed with a protein-mediated antibiotic activity, which is upregulated in response to danger signals and sepsis. Dependence on host nutrients could be a generic "Achilles' heel" of intracellular pathogens and LDs a suitable chokepoint harnessed by innate immunity to organize a front-line defense. Here, we will provide a brief overview of the state of the conflict and discuss potential mechanisms driving the formation of the 'defensive-LDs' functioning as hubs of innate immunity.
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Affiliation(s)
- Rémi Safi
- Lipid Trafficking and Disease Group, Institut d'Investigacions Biomèdiques August Pi I Sunyer (IDIBAPS), Barcelona, Spain
- Josep Carreras Leukemia Research Institute, Barcelona, Spain
| | - Miguel Sánchez-Álvarez
- Centro Nacional de Investigaciones Cardiovasculares (CNIC), Madrid, Spain
- Instituto de Investigaciones Biomédicas Alberto Sols (IIB), Madrid, Spain
| | - Marta Bosch
- Lipid Trafficking and Disease Group, Institut d'Investigacions Biomèdiques August Pi I Sunyer (IDIBAPS), Barcelona, Spain
- Department of Biomedical Sciences, Faculty of Medicine, Universitat de Barcelona, Barcelona, Spain
| | - Caroline Demangel
- Immunobiology and Therapy Unit, Institut Pasteur, Université Paris Cité, INSERM U1224, Paris, France
| | - Robert G Parton
- Institute for Molecular Bioscience (IMB), Brisbane, Queensland, Australia
- Centre for Microscopy and Microanalysis (CMM), University of Queensland, Brisbane, Queensland, Australia
| | - Albert Pol
- Lipid Trafficking and Disease Group, Institut d'Investigacions Biomèdiques August Pi I Sunyer (IDIBAPS), Barcelona, Spain
- Department of Biomedical Sciences, Faculty of Medicine, Universitat de Barcelona, Barcelona, Spain
- Institució Catalana de Recerca i Estudis Avançats (ICREA), Barcelona, Spain
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3
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Liu L, Zhang Z, Liu H, Zhu S, Zhou T, Wang C, Hu M. Identification and characterisation of the haemozoin of Haemonchus contortus. Parasit Vectors 2023; 16:88. [PMID: 36879311 PMCID: PMC9990328 DOI: 10.1186/s13071-023-05714-3] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/20/2023] [Accepted: 02/22/2023] [Indexed: 03/08/2023] Open
Abstract
BACKGROUND Most haematophagous organisms constantly suck the host's haemoglobin, which produces toxic free haem. This toxic haem aggregation into the nontoxic crystallisation complex known as haemozoin represents one of the most important detoxification pathways in living organisms, but very little is known about the features of haemozoin in parasitic nematodes. Here, we identified and characterised the haemozoin of an economically significant blood-sucking nematode, Haemonchus contortus. METHODS Using electron microscopy, spectrophotometry analyses and biochemical approaches, haemozoin crystallisation was identified and characterised in parasitic fourth-stage larvae (L4s) and/or adult worms as well as L4s of in vitro culture. RESULTS The haemozoin was formed in intestinal lipid droplets of the parasitic L4s and adult worms. The characterisation of the haemozoin showed regularly spherical structures and had a 400-nm absorption peak. Furthermore, the haemozoin in in vitro cultured L4s was associated with the culture time and concentration of red blood cells added into the medium, and its formation could be inhibited by chloroquine-derived drugs. CONCLUSIONS This work provides detailed insight into the haemozoin formation of H. contortus and should have important implications for developing novel therapeutic targets against this parasite or related haematophagous organisms.
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Affiliation(s)
- Lu Liu
- State Key Laboratory of Agricultural Microbiology, College of Veterinary Medicine, Huazhong Agricultural University, Wuhan, 430070, China
| | - Zongshan Zhang
- State Key Laboratory of Agricultural Microbiology, College of Veterinary Medicine, Huazhong Agricultural University, Wuhan, 430070, China
| | - Hui Liu
- State Key Laboratory of Agricultural Microbiology, College of Veterinary Medicine, Huazhong Agricultural University, Wuhan, 430070, China
| | - Shengnan Zhu
- State Key Laboratory of Agricultural Microbiology, College of Veterinary Medicine, Huazhong Agricultural University, Wuhan, 430070, China
| | - Taoxun Zhou
- State Key Laboratory of Agricultural Microbiology, College of Veterinary Medicine, Huazhong Agricultural University, Wuhan, 430070, China
| | - Chunqun Wang
- State Key Laboratory of Agricultural Microbiology, College of Veterinary Medicine, Huazhong Agricultural University, Wuhan, 430070, China.
| | - Min Hu
- State Key Laboratory of Agricultural Microbiology, College of Veterinary Medicine, Huazhong Agricultural University, Wuhan, 430070, China.
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4
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Monson EA, Trenerry AM, Laws JL, Mackenzie JM, Helbig KJ. Lipid droplets and lipid mediators in viral infection and immunity. FEMS Microbiol Rev 2021; 45:fuaa066. [PMID: 33512504 PMCID: PMC8371277 DOI: 10.1093/femsre/fuaa066] [Citation(s) in RCA: 50] [Impact Index Per Article: 16.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/28/2020] [Accepted: 12/02/2020] [Indexed: 12/14/2022] Open
Abstract
Lipid droplets (LDs) contribute to key pathways important for the physiology and pathophysiology of cells. In a homeostatic view, LDs regulate the storage of neutral lipids, protein sequestration, removal of toxic lipids and cellular communication; however, recent advancements in the field show these organelles as essential for various cellular stress response mechanisms, including inflammation and immunity, with LDs acting as hubs that integrate metabolic and inflammatory processes. The accumulation of LDs has become a hallmark of infection, and is often thought to be virally driven; however, recent evidence is pointing to a role for the upregulation of LDs in the production of a successful immune response to viral infection. The fatty acids housed in LDs are also gaining interest due to the role that these lipid species play during viral infection, and their link to the synthesis of bioactive lipid mediators that have been found to have a very complex role in viral infection. This review explores the role of LDs and their subsequent lipid mediators during viral infections and poses a paradigm shift in thinking in the field, whereby LDs may play pivotal roles in protecting the host against viral infection.
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Affiliation(s)
- Ebony A Monson
- School of Life Sciences, La Trobe University, Melbourne, Australia, 3083
| | - Alice M Trenerry
- Department of Microbiology and Immunology, University of Melbourne, at the Peter Doherty Institute for Infection and Immunity, Melbourne, Australia, 3000
| | - Jay L Laws
- School of Life Sciences, La Trobe University, Melbourne, Australia, 3083
| | - Jason M Mackenzie
- Department of Microbiology and Immunology, University of Melbourne, at the Peter Doherty Institute for Infection and Immunity, Melbourne, Australia, 3000
| | - Karla J Helbig
- School of Life Sciences, La Trobe University, Melbourne, Australia, 3083
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Kapishnikov S, Hempelmann E, Elbaum M, Als‐Nielsen J, Leiserowitz L. Malaria Pigment Crystals: The Achilles' Heel of the Malaria Parasite. ChemMedChem 2021; 16:1515-1532. [PMID: 33523575 PMCID: PMC8252759 DOI: 10.1002/cmdc.202000895] [Citation(s) in RCA: 28] [Impact Index Per Article: 9.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/17/2020] [Indexed: 12/14/2022]
Abstract
The biogenic formation of hemozoin crystals, a crucial process in heme detoxification by the malaria parasite, is reviewed as an antimalarial drug target. We first focus on the in-vivo formation of hemozoin. A model is presented, based on native-contrast 3D imaging obtained by X-ray and electron microscopy, that hemozoin nucleates at the inner membrane leaflet of the parasitic digestive vacuole, and grows in the adjacent aqueous medium. Having observed quantities of hemoglobin and hemozoin in the digestive vacuole, we present a model that heme liberation from hemoglobin and hemozoin formation is an assembly-line process. The crystallization is preceded by reaction between heme monomers yielding hematin dimers involving fewer types of isomers than in synthetic hemozoin; this is indicative of protein-induced dimerization. Models of antimalarial drugs binding onto hemozoin surfaces are reviewed. This is followed by a description of bromoquine, a chloroquine drug analogue, capping a significant fraction of hemozoin surfaces within the digestive vacuole and accumulation of the drug, presumably a bromoquine-hematin complex, at the vacuole's membrane.
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Affiliation(s)
- Sergey Kapishnikov
- Dept. of Chemical Research SupportWeizmann Institute of ScienceRehovot7610001Israel
| | - Ernst Hempelmann
- Center of Cellular and Molecular Biology of DiseasesInstituto de Investigaciones Científicas y Servicios de Alta Tecnología (INDICASAT AIP)City of Knowledge0843 (Republic ofPanama
| | - Michael Elbaum
- Dept. of Chemical and Biological PhysicsWeizmann Institute of ScienceRehovot7610001Israel
| | - Jens Als‐Nielsen
- Niels Bohr InstituteUniversity of Copenhagen2100CopenhagenDenmark
| | - Leslie Leiserowitz
- Dept. of Molecular Chemistry and Materials ScienceWeizmann Institute of ScienceRehovot7610001Israel
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6
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Brandão-Bezerra L, de Carvalho Martins JSC, de Oliveira RMF, Lopes-Torres EJ, Neves RH, Corrêa CL, Machado-Silva JR. Long-term ethanol intake causes morphological changes in Schistosoma mansoni adult worms in mice. Exp Parasitol 2019; 203:30-35. [PMID: 31150655 DOI: 10.1016/j.exppara.2019.05.010] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/21/2018] [Revised: 05/03/2019] [Accepted: 05/27/2019] [Indexed: 12/18/2022]
Abstract
Schistosoma mansoni adult worms are extensively challenged by reactive oxygen species from intrinsic sources. However, the effects of extrinsic sources such as ethanol have not been looked at in schistosomes. We examined adult worms recovered from ethanol-consuming mice by light (LM), confocal (CM) and scanning electron microscopy (SEM) to address this question. Schistosomiasis-infected mice were orally gavaged with 18% (v/v) ethanol from 35 to 63 days post-infection, when they were euthanized. CM examination revealed reduced germ cells density (-36%, p = 0.0001) and sperm density (-58%, p = 0.0001) in testicular lobes, and immature cells in seminal vesicle compared to unexposed control worms. Female worms showed reduced density of vitellin glands (-71%, p = 0.0001), maturation of oocytes (-7%, p = 0.0071) and reduced spermatozoa density (-23%, p = 0.0002) within the seminal receptacle. SEM revealed remarkable damages in male's tegument, including tubercles flattening, tegumental peeling and erosive lesions. Given that lipids are present in reproductive system and tegument, our results suggest that phenotypic changes are due to ethanol-induced lipid peroxidation. To the best of our knowledge, this is the first report revealing the biological action of ethanol intake on adult schistosomes in vivo.
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Affiliation(s)
- Luciana Brandão-Bezerra
- Romero Lascasas Porto Laboratory of Helminthology, Department of Microbiology, Immunology and Parasitology, School of Medical Sciences, Rio de Janeiro State University, Brazil
| | - Jéssica Santa Cruz de Carvalho Martins
- Romero Lascasas Porto Laboratory of Helminthology, Department of Microbiology, Immunology and Parasitology, School of Medical Sciences, Rio de Janeiro State University, Brazil
| | - Regina Maria Figueiredo de Oliveira
- Romero Lascasas Porto Laboratory of Helminthology, Department of Microbiology, Immunology and Parasitology, School of Medical Sciences, Rio de Janeiro State University, Brazil
| | - Eduardo José Lopes-Torres
- Romero Lascasas Porto Laboratory of Helminthology, Department of Microbiology, Immunology and Parasitology, School of Medical Sciences, Rio de Janeiro State University, Brazil
| | - Renata Heisler Neves
- Romero Lascasas Porto Laboratory of Helminthology, Department of Microbiology, Immunology and Parasitology, School of Medical Sciences, Rio de Janeiro State University, Brazil
| | - Christiane Leal Corrêa
- Department of Pathology and Laboratories, School of Medical Sciences, Rio de Janeiro State University, Brazil; Medicine School, Estácio de Sá University, Brazil
| | - José Roberto Machado-Silva
- Romero Lascasas Porto Laboratory of Helminthology, Department of Microbiology, Immunology and Parasitology, School of Medical Sciences, Rio de Janeiro State University, Brazil.
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7
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Abdelgelil NH, Abdellatif MZM, Abdel-Hafeez EH, Belal US, Mohamed RM, Abdel-Razik ARH, Hassanin KMA, Abdel-Wahab A. Effects of iron chelating agent on Schistosoma mansoni infected murine model. Biomed Pharmacother 2018; 109:28-38. [PMID: 30391706 DOI: 10.1016/j.biopha.2018.10.036] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/12/2018] [Revised: 10/08/2018] [Accepted: 10/09/2018] [Indexed: 12/29/2022] Open
Abstract
Schistosomiasis is one of the major health problems in many tropical and developing countries. Infection takes place once cerceriae penetrate human skin, then it changed into schistosomules. The schistosomules takes iron in the form of heme from host's haemoglobin, ferritin and transferrin. Iron is a vital element not only for growth and sexual maturity of schistosomules to adults but also for oogenesis. Since the trapped eggs are the pathological causative agent for most of pathogenesis and complications, the current work was designed to study the effects of early deprivation of schistosomules from iron in the host (in vivo) by chelating it with deferoxamine (DFO). The iron chelation has effects on growth, maturity and egg deposition, as well as it has ameliorative effects on liver pathology such as hepatic fibrosis. Mice were classified into four groups, normal control, DFO treated only, Schistosoma mansoni (S. mansoni) infected DFO untreated and S. mansoni infected DFO treated. The infected DFO treated mice showed significant reduction in fecal egg excretion with increased percentage of dead eggs and this was accompanied with a significant reduction of both total worm burden and hepatic egg load and increased dead egg percentage compared to the infected DFO untreated group. There was also a significant reduction in both serum and hepatic tissue ferritin concentrations in the infected DFO treated mice in comparison to the infected DFO untreated group. Additionally, a significant decrease in number and size of granulomas with subsequent improvement of liver fibrosis was recorded in the infected DFO treated group. This immunopathology was also associated with significant up regulation of Interlukine12 (IL12), Interferon gamma (IFN γ) and significant down regulation in interleukin4 (IL4), interleukin10 (IL10) in both serum and hepatic tissue in the infected DFO treated compared to other groups. Entirely, DFO succeeded in diminishing the growth, maturity and fecundity of S. mansoni with a subsequent improvement of hepatic pathology. As a result of the above findings, it can be concluded that DFO could be considered as a useful treatment against schistosomal infection.
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Affiliation(s)
- Noha H Abdelgelil
- Department of Parasitology, Faculty of Medicine, Minia University, Minia 61519, Egypt
| | - Manal Z M Abdellatif
- Department of Parasitology, Faculty of Medicine, Minia University, Minia 61519, Egypt
| | - Ekhlas H Abdel-Hafeez
- Department of Parasitology, Faculty of Medicine, Minia University, Minia 61519, Egypt
| | - Usama S Belal
- Department of Parasitology, Faculty of Medicine, Minia University, Minia 61519, Egypt
| | - Rabie M Mohamed
- Department of Parasitology, Faculty of Medicine, Minia University, Minia 61519, Egypt
| | - Abdel-Razik H Abdel-Razik
- Department of Histology, Faculty of Veterinary Medicine, Beni - Suef University, Beni - Suef 62511, Egypt
| | - Kamel M A Hassanin
- Department of Biochemistry, Faculty of Veterinary Medicine, Minia University, Minia 61519, Egypt
| | - Ahmed Abdel-Wahab
- Department of Physiology, Faculty of Veterinary Medicine, Minia University, Minia 61519, Egypt.
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8
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Ferreira CM, Stiebler R, Saraiva FM, Lechuga GC, Walter-Nuno AB, Bourguignon SC, Gonzalez MS, Azambuja P, Gandara ACP, Menna-Barreto RFS, Paiva-Silva GO, Paes MC, Oliveira MF. Heme crystallization in a Chagas disease vector acts as a redox-protective mechanism to allow insect reproduction and parasite infection. PLoS Negl Trop Dis 2018; 12:e0006661. [PMID: 30036366 PMCID: PMC6084092 DOI: 10.1371/journal.pntd.0006661] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/02/2018] [Revised: 08/02/2018] [Accepted: 07/03/2018] [Indexed: 12/18/2022] Open
Abstract
Heme crystallization as hemozoin represents the dominant mechanism of heme disposal in blood feeding triatomine insect vectors of the Chagas disease. The absence of drugs or vaccine for the Chagas disease causative agent, the parasite Trypanosoma cruzi, makes the control of vector population the best available strategy to limit disease spread. Although heme and redox homeostasis regulation is critical for both triatomine insects and T. cruzi, the physiological relevance of hemozoin for these organisms remains unknown. Here, we demonstrate that selective blockage of heme crystallization in vivo by the antimalarial drug quinidine, caused systemic heme overload and redox imbalance in distinct insect tissues, assessed by spectrophotometry and fluorescence microscopy. Quinidine treatment activated compensatory defensive heme-scavenging mechanisms to cope with excessive heme, as revealed by biochemical hemolymph analyses, and fat body gene expression. Importantly, egg production, oviposition, and total T. cruzi parasite counts in R. prolixus were significantly reduced by quinidine treatment. These effects were reverted by oral supplementation with the major insect antioxidant urate. Altogether, these data underscore the importance of heme crystallization as the main redox regulator for triatomine vectors, indicating the dual role of hemozoin as a protective mechanism to allow insect fertility, and T. cruzi life-cycle. Thus, targeting heme crystallization in insect vectors represents an innovative way for Chagas disease control, by reducing simultaneously triatomine reproduction and T. cruzi transmission. Chagas disease is a fatal illness caused by Trypanosoma cruzi parasites, which are transmitted by blood sucking triatomine insect vectors. Although blood is a natural food source for these insects, its digestion releases toxic products, which poses a dietary challenge for both triatomine insects and trypanosomes. To overcome this, triatomines eliminate these toxic blood products by a unique process of heme crystallization into hemozoin that take place in their digestive tract. Here we describe that this detoxification process represents the major mechanism for redox balance control, and is necessary to allow triatomine insect reproduction, and Trypanosoma cruzi infection. Disruption of heme crystallization in triatomine insects thus represents a new venue for Chagas disease control, by targeting at the same time insect reproduction and parasite transmission.
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Affiliation(s)
- Caroline M. Ferreira
- Instituto de Bioquímica Médica Leopoldo de Meis, Universidade Federal do Rio de Janeiro, Rio de Janeiro, Rio de Janeiro, Brazil
- Instituto Nacional de Ciência e Tecnologia em Entomologia Molecular (INCT-EM), Rio de Janeiro, Rio de Janeiro, Brazil
| | - Renata Stiebler
- Instituto de Bioquímica Médica Leopoldo de Meis, Universidade Federal do Rio de Janeiro, Rio de Janeiro, Rio de Janeiro, Brazil
- Instituto Nacional de Ciência e Tecnologia em Entomologia Molecular (INCT-EM), Rio de Janeiro, Rio de Janeiro, Brazil
- Instituto Oswaldo Cruz, Fiocruz, Rio de Janeiro, Rio de Janeiro, Brazil
| | - Francis M. Saraiva
- Instituto Nacional de Ciência e Tecnologia em Entomologia Molecular (INCT-EM), Rio de Janeiro, Rio de Janeiro, Brazil
- Instituto de Biologia Roberto Alcântara Gomes, Universidade do Estado do Rio de Janeiro, Rio de Janeiro, Rio de Janeiro, Brazil
| | - Guilherme C. Lechuga
- Departamento de Biologia Celular e Molecular, Universidade Federal Fluminense, Niterói, Rio de Janeiro, Brazil
| | - Ana Beatriz Walter-Nuno
- Instituto de Bioquímica Médica Leopoldo de Meis, Universidade Federal do Rio de Janeiro, Rio de Janeiro, Rio de Janeiro, Brazil
- Instituto Nacional de Ciência e Tecnologia em Entomologia Molecular (INCT-EM), Rio de Janeiro, Rio de Janeiro, Brazil
| | - Saulo C. Bourguignon
- Departamento de Biologia Celular e Molecular, Universidade Federal Fluminense, Niterói, Rio de Janeiro, Brazil
| | - Marcelo S. Gonzalez
- Instituto Nacional de Ciência e Tecnologia em Entomologia Molecular (INCT-EM), Rio de Janeiro, Rio de Janeiro, Brazil
- Departamento de Biologia Geral, Universidade Federal Fluminense, Niterói, Rio de Janeiro, Brazil
| | - Patrícia Azambuja
- Instituto Nacional de Ciência e Tecnologia em Entomologia Molecular (INCT-EM), Rio de Janeiro, Rio de Janeiro, Brazil
- Instituto Oswaldo Cruz, Fiocruz, Rio de Janeiro, Rio de Janeiro, Brazil
| | - Ana Caroline P. Gandara
- Instituto de Bioquímica Médica Leopoldo de Meis, Universidade Federal do Rio de Janeiro, Rio de Janeiro, Rio de Janeiro, Brazil
- Instituto Nacional de Ciência e Tecnologia em Entomologia Molecular (INCT-EM), Rio de Janeiro, Rio de Janeiro, Brazil
| | | | - Gabriela O. Paiva-Silva
- Instituto de Bioquímica Médica Leopoldo de Meis, Universidade Federal do Rio de Janeiro, Rio de Janeiro, Rio de Janeiro, Brazil
- Instituto Nacional de Ciência e Tecnologia em Entomologia Molecular (INCT-EM), Rio de Janeiro, Rio de Janeiro, Brazil
| | - Marcia C. Paes
- Instituto Nacional de Ciência e Tecnologia em Entomologia Molecular (INCT-EM), Rio de Janeiro, Rio de Janeiro, Brazil
- Instituto de Biologia Roberto Alcântara Gomes, Universidade do Estado do Rio de Janeiro, Rio de Janeiro, Rio de Janeiro, Brazil
| | - Marcus F. Oliveira
- Instituto de Bioquímica Médica Leopoldo de Meis, Universidade Federal do Rio de Janeiro, Rio de Janeiro, Rio de Janeiro, Brazil
- Instituto Nacional de Ciência e Tecnologia em Entomologia Molecular (INCT-EM), Rio de Janeiro, Rio de Janeiro, Brazil
- * E-mail:
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9
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Vallochi AL, Teixeira L, Oliveira KDS, Maya-Monteiro CM, Bozza PT. Lipid Droplet, a Key Player in Host-Parasite Interactions. Front Immunol 2018; 9:1022. [PMID: 29875768 PMCID: PMC5974170 DOI: 10.3389/fimmu.2018.01022] [Citation(s) in RCA: 76] [Impact Index Per Article: 12.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/31/2018] [Accepted: 04/24/2018] [Indexed: 12/18/2022] Open
Abstract
Lipid droplets (lipid bodies, LDs) are dynamic organelles that have important roles in regulating lipid metabolism, energy homeostasis, cell signaling, membrane trafficking, and inflammation. LD biogenesis, composition, and functions are highly regulated and may vary according to the stimuli, cell type, activation state, and inflammatory environment. Increased cytoplasmic LDs are frequently observed in leukocytes and other cells in a number of infectious diseases. Accumulating evidence reveals LDs participation in fundamental mechanisms of host-pathogen interactions, including cell signaling and immunity. LDs are sources of eicosanoid production, and may participate in different aspects of innate signaling and antigen presentation. In addition, intracellular pathogens evolved mechanisms to subvert host metabolism and may use host LDs, as ways of immune evasion and nutrients source. Here, we review mechanisms of LDs biogenesis and their contributions to the infection progress, and discuss the latest discoveries on mechanisms and pathways involving LDs roles as regulators of the immune response to protozoan infection.
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Affiliation(s)
- Adriana Lima Vallochi
- Laboratório de Imunofarmacologia, Instituto Oswaldo Cruz, Fundação Oswaldo Cruz (FIOCRUZ), Rio de Janeiro, Brazil
| | | | | | | | - Patricia T. Bozza
- Laboratório de Imunofarmacologia, Instituto Oswaldo Cruz, Fundação Oswaldo Cruz (FIOCRUZ), Rio de Janeiro, Brazil
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10
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Ferreira CM, Oliveira MP, Paes MC, Oliveira MF. Modulation of mitochondrial metabolism as a biochemical trait in blood feeding organisms: the redox vampire hypothesis redux. Cell Biol Int 2018; 42:683-700. [PMID: 29384241 DOI: 10.1002/cbin.10945] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/30/2017] [Accepted: 01/27/2018] [Indexed: 12/31/2022]
Abstract
Hematophagous organisms undergo remarkable metabolic changes during the blood digestion process, increasing fermentative glucose metabolism, and reducing respiratory rates, both consequence of functional mitochondrial remodeling. Here, we review the pathways involved in energy metabolism and mitochondrial functionality in a comparative framework across different hematophagous species, and consider how these processes regulate redox homeostasis during blood digestion. The trend across distinct species indicate that a switch in energy metabolism might represent an important defensive mechanism to avoid the potential harmful interaction of oxidants generated from aerobic energy metabolism with products derived from blood digestion. Indeed, in insect vectors, blood feeding transiently reduces respiratory rates and oxidant production, irrespective of tissue and insect model. On the other hand, a different scenario is observed in several unrelated parasite species when exposed to blood digestion products, as respiratory rates reduce and mitochondrial oxidant production increase. The emerging picture indicates that re-wiring of energy metabolism, through reduced mitochondrial function, culminates in improved tolerance to redox insults and seems to represent a key step for hematophagous organisms to cope with the overwhelming and potentially toxic blood meal.
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Affiliation(s)
- Caroline M Ferreira
- Instituto de Bioquímica Médica Leopoldo de Meis, Universidade Federal do Rio de Janeiro, Rio de Janeiro, RJ, 21941-590, Brazil.,Instituto Nacional de Ciência e Tecnologia em Entomologia Molecular (INCT-EM), Rio de Janeiro, RJ, 21941-590, Brazil
| | - Matheus P Oliveira
- Instituto de Bioquímica Médica Leopoldo de Meis, Universidade Federal do Rio de Janeiro, Rio de Janeiro, RJ, 21941-590, Brazil.,Instituto Nacional de Ciência e Tecnologia em Entomologia Molecular (INCT-EM), Rio de Janeiro, RJ, 21941-590, Brazil.,Department of Integrative Biology and Physiology, University of California, Los Angeles, CA, 90095, USA
| | - Marcia C Paes
- Instituto Nacional de Ciência e Tecnologia em Entomologia Molecular (INCT-EM), Rio de Janeiro, RJ, 21941-590, Brazil.,Instituto de Biologia Roberto Alcântara Gomes, Universidade do Estado do Rio de Janeiro, Rio de Janeiro, RJ, 20551-030, Brazil
| | - Marcus F Oliveira
- Instituto de Bioquímica Médica Leopoldo de Meis, Universidade Federal do Rio de Janeiro, Rio de Janeiro, RJ, 21941-590, Brazil.,Instituto Nacional de Ciência e Tecnologia em Entomologia Molecular (INCT-EM), Rio de Janeiro, RJ, 21941-590, Brazil
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11
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Whiten SR, Eggleston H, Adelman ZN. Ironing out the Details: Exploring the Role of Iron and Heme in Blood-Sucking Arthropods. Front Physiol 2018; 8:1134. [PMID: 29387018 PMCID: PMC5776124 DOI: 10.3389/fphys.2017.01134] [Citation(s) in RCA: 35] [Impact Index Per Article: 5.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/31/2017] [Accepted: 12/22/2017] [Indexed: 12/12/2022] Open
Abstract
Heme and iron are essential molecules for many physiological processes and yet have the ability to cause oxidative damage such as lipid peroxidation, protein degradation, and ultimately cell death if not controlled. Blood-sucking arthropods have evolved diverse methods to protect themselves against iron/heme-related damage, as the act of bloodfeeding itself is high risk, high reward process. Protective mechanisms in medically important arthropods include the midgut peritrophic matrix in mosquitoes, heme aggregation into the crystalline structure hemozoin in kissing bugs and hemosomes in ticks. Once heme and iron pass these protective mechanisms they are presumed to enter the midgut epithelial cells via membrane-bound transporters, though relatively few iron or heme transporters have been identified in bloodsucking arthropods. Upon iron entry into midgut epithelial cells, ferritin serves as the universal storage protein and transport for dietary iron in many organisms including arthropods. In addition to its role as a nutrient, heme is also an important signaling molecule in the midgut epithelial cells for many physiological processes including vitellogenesis. This review article will summarize recent advancements in heme/iron uptake, detoxification and exportation in bloodfeeding arthropods. While initial strides have been made at ironing out the role of dietary iron and heme in arthropods, much still remains to be discovered as these molecules may serve as novel targets for the control of many arthropod pests.
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Affiliation(s)
- Shavonn R Whiten
- Department of Entomology, Texas A&M University, College Station, TX, United States
| | - Heather Eggleston
- Genetics Graduate Program, Texas A&M University, College Station, TX, United States
| | - Zach N Adelman
- Department of Entomology, Texas A&M University, College Station, TX, United States
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12
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Gupta P, Mehrotra S, Sharma A, Chugh M, Pandey R, Kaushik A, Khurana S, Srivastava N, Srivastava T, Deshmukh A, Panda A, Aggarwal P, Bhavesh NS, Bhatnagar RK, Mohmmed A, Gupta D, Malhotra P. Exploring Heme and Hemoglobin Binding Regions of Plasmodium Heme Detoxification Protein for New Antimalarial Discovery. J Med Chem 2017; 60:8298-8308. [PMID: 28949547 DOI: 10.1021/acs.jmedchem.7b00089] [Citation(s) in RCA: 17] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/29/2023]
Abstract
Hemoglobin degradation/hemozoin formation, essential steps in the Plasmodium life cycle, are targets of existing antimalarials. The pathway still offers vast possibilities to be explored for new antimalarial discoveries. Here, we characterize heme detoxification protein, PfHDP, a major protein involved in hemozoin formation, as a novel drug target. Using in silico and biochemical approaches, we identified two heme binding sites and a hemoglobin binding site in PfHDP. Treatment of Plasmodium falciparum 3D7 parasites with peptide corresponding to the hemoglobin binding domain in PfHDP resulted in food vacuole abnormalities similar to that seen with a cysteine protease inhibitor, E-64 (I-1). Screening of compounds that bound the modeled PfHDP structure in the heme/hemoglobin-binding pockets from Maybridge Screening Collection identified a compound, ML-2, that inhibited parasite growth in a dose-dependent manner, thus paving the way for testing its potential as a new drug candidate. These results provide functional insights into the role of PfHDP in Hz formation and further suggest that PfHDP could be an important drug target to combat malaria.
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Affiliation(s)
- Priya Gupta
- Malaria Biology Group, International Centre for Genetic Engineering and Biotechnology , Aruna Asaf Ali Marg, New Delhi 110067, India
| | - Sonali Mehrotra
- Malaria Biology Group, International Centre for Genetic Engineering and Biotechnology , Aruna Asaf Ali Marg, New Delhi 110067, India
| | - Anil Sharma
- Malaria Biology Group, International Centre for Genetic Engineering and Biotechnology , Aruna Asaf Ali Marg, New Delhi 110067, India
| | - Monika Chugh
- Malaria Biology Group, International Centre for Genetic Engineering and Biotechnology , Aruna Asaf Ali Marg, New Delhi 110067, India
| | - Rajan Pandey
- Translational Bioinformatics Group, International Centre for Genetic Engineering and Biotechnology , Aruna Asaf Ali Marg, New Delhi 110067, India
| | - Abhinav Kaushik
- Translational Bioinformatics Group, International Centre for Genetic Engineering and Biotechnology , Aruna Asaf Ali Marg, New Delhi 110067, India
| | - Sachin Khurana
- Malaria Biology Group, International Centre for Genetic Engineering and Biotechnology , Aruna Asaf Ali Marg, New Delhi 110067, India
| | - Neha Srivastava
- Malaria Biology Group, International Centre for Genetic Engineering and Biotechnology , Aruna Asaf Ali Marg, New Delhi 110067, India
| | - Tarushikha Srivastava
- Malaria Biology Group, International Centre for Genetic Engineering and Biotechnology , Aruna Asaf Ali Marg, New Delhi 110067, India
| | - Arunaditya Deshmukh
- Malaria Biology Group, International Centre for Genetic Engineering and Biotechnology , Aruna Asaf Ali Marg, New Delhi 110067, India.,Centre for Biotechnology, Maharishi Dayanand University Rohtak , Haryana 123401, India
| | - Ashutosh Panda
- Department of Microbiology, All India Institute of Medical Sciences , New Delhi 110029, India
| | - Priyanka Aggarwal
- Transcriptional Regulation Group, International Centre for Genetic Engineering and Biotechnology , Aruna Asaf Ali Marg, New Delhi 110067, India
| | - Neel Sarovar Bhavesh
- Transcriptional Regulation Group, International Centre for Genetic Engineering and Biotechnology , Aruna Asaf Ali Marg, New Delhi 110067, India
| | - Raj K Bhatnagar
- Insect Resistance Group, International Centre for Genetic Engineering and Biotechnology , Aruna Asaf Ali Marg, New Delhi 110067, India
| | - Asif Mohmmed
- Parasite Cell Biology Group, International Centre for Genetic Engineering and Biotechnology , Aruna Asaf Ali Marg, New Delhi 110067, India
| | - Dinesh Gupta
- Translational Bioinformatics Group, International Centre for Genetic Engineering and Biotechnology , Aruna Asaf Ali Marg, New Delhi 110067, India
| | - Pawan Malhotra
- Malaria Biology Group, International Centre for Genetic Engineering and Biotechnology , Aruna Asaf Ali Marg, New Delhi 110067, India
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13
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Okombo J, Singh K, Mayoka G, Ndubi F, Barnard L, Njogu PM, Njoroge M, Gibhard L, Brunschwig C, Vargas M, Keiser J, Egan TJ, Chibale K. Antischistosomal Activity of Pyrido[1,2-a]benzimidazole Derivatives and Correlation with Inhibition of β-Hematin Formation. ACS Infect Dis 2017; 3:411-420. [PMID: 28440625 DOI: 10.1021/acsinfecdis.6b00205] [Citation(s) in RCA: 15] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/24/2023]
Abstract
The extensive use of praziquantel against schistosomiasis raises concerns about drug resistance. New therapeutic alternatives targeting critical pathways within the parasite are therefore urgently needed. Hemozoin formation in Schistosoma presents one such target. We assessed the in vitro antischistosomal activity of pyrido[1,2-a]benzimidazoles (PBIs) and investigated correlations with their ability to inhibit β-hematin formation. We further evaluated the in vivo efficacy of representative compounds in experimental mice and conducted pharmacokinetic analysis on the most potent. At 10 μM, 48/57 compounds resulted in >70% mortality of newly transformed schistosomula, whereas 37 of these maintained >60% mortality of adult S. mansoni. No correlations were observed between β-hematin inhibitory and antischistosomal activities against both larval and adult parasites, suggesting possible presence of other target(s) or a mode of inhibition of crystal formation that is not adequately modeled by the assay. The most active compound in vivo showed 58.7 and 61.3% total and female worm burden reduction, respectively. Pharmacokinetic analysis suggested solubility-limited absorption and high hepatic clearance as possible contributors to the modest efficacy despite good in vitro activity. The PBIs evaluated in this report thus merit further optimization to improve their efficacy and to elucidate their possible mode of action.
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Affiliation(s)
- John Okombo
- Department of Chemistry, University of Cape Town, Rondebosch 7701, South Africa
| | - Kawaljit Singh
- Department of Chemistry, University of Cape Town, Rondebosch 7701, South Africa
| | - Godfrey Mayoka
- Department of Chemistry, University of Cape Town, Rondebosch 7701, South Africa
| | - Ferdinand Ndubi
- Department of Chemistry, University of Cape Town, Rondebosch 7701, South Africa
| | - Linley Barnard
- Department of Chemistry, University of Cape Town, Rondebosch 7701, South Africa
| | - Peter M. Njogu
- Department of Pharmaceutical Chemistry, University of Nairobi, P.O. Box 19676, Nairobi 00202, Kenya
| | - Mathew Njoroge
- Drug Discovery and Development Centre (H3D),
Division of Clinical Pharmacology, Department of Medicine, University of Cape Town, Observatory 7925, South Africa
| | - Liezl Gibhard
- Drug Discovery and Development Centre (H3D),
Division of Clinical Pharmacology, Department of Medicine, University of Cape Town, Observatory 7925, South Africa
| | - Christel Brunschwig
- Drug Discovery and Development Centre (H3D),
Division of Clinical Pharmacology, Department of Medicine, University of Cape Town, Observatory 7925, South Africa
| | - Mireille Vargas
- Department of Medical Parasitology and
Infection Biology, Swiss Tropical and Public Health Institute, 4051 Basel, Switzerland
- University of Basel, 4003 Basel, Switzerland
| | - Jennifer Keiser
- Department of Medical Parasitology and
Infection Biology, Swiss Tropical and Public Health Institute, 4051 Basel, Switzerland
- University of Basel, 4003 Basel, Switzerland
| | - Timothy J. Egan
- Department of Chemistry, University of Cape Town, Rondebosch 7701, South Africa
| | - Kelly Chibale
- Department of Chemistry, University of Cape Town, Rondebosch 7701, South Africa
- South African Medical Research Council,
Drug Discovery and Development Research Unit, University of Cape Town, Rondebosch 7701, South Africa
- Institute of Infectious Disease and Molecular Medicine, University of Cape Town, Rondebosch 7701, South Africa
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14
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Xiao SH, Sun J. Schistosoma hemozoin and its possible roles. Int J Parasitol 2016; 47:171-183. [PMID: 28012717 DOI: 10.1016/j.ijpara.2016.10.005] [Citation(s) in RCA: 17] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/22/2016] [Revised: 10/10/2016] [Accepted: 10/13/2016] [Indexed: 12/20/2022]
Abstract
More than 95years ago Schistosoma pigment had been deemed as a degradation product of haemoglobin. Until the 1950s, scientists initiated to pay attention to understand the hematophagous habit of schistosomes, and to study the degradation of haemoglobin as well as the formation of hemozoin inside the gut of the worms. For a long time, the formation of hemozoin in both Plasmodium and in Schistosoma was considered to be the major route of heme detoxification, and hemozoin served a role in waste disposal. At the beginning of this century, the chemical structure of Schistosoma pigment was confirmed to be identical to that of malarial pigment (hemozoin) and its synthetic analogue, β-hematin. Since then, studies on Schistosoma hemozoin have been investigated by some workers and the results showed that Schistosoma hemozoin may play important roles in pathogenicity, immune modulation, iron supply for egg formation, and interaction with some anti-schistosomal drugs. In this review, we briefly review and discuss the hematophagous habit of schistosomes, degradation of haemoglobin, formation of hemozoin in the worm gut, and possible roles of hemozoin.
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Affiliation(s)
- Shu-Hua Xiao
- National Institute of Parasitic Diseases, Chinese Center for Disease Control and Prevention, Key Laboratory of Parasite and Vector Biology, MOH, WHO Collaborating Centre for Malaria, Schistosomiasis, and Filariasis, Shanghai 200025, China.
| | - Jun Sun
- Institute for Infectious Disease and Vaccine Development, Tongji University School of Medicine, Shanghai 200092, China.
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15
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Hemozoin is a product of heme detoxification in the gut of the most medically important species of the family Opisthorchiidae. Int J Parasitol 2016; 46:147-156. [PMID: 26812025 DOI: 10.1016/j.ijpara.2015.12.003] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/28/2015] [Revised: 12/08/2015] [Accepted: 12/10/2015] [Indexed: 02/06/2023]
Abstract
Many species of trematodes such as Schistosoma spp., Fasciola hepatica and Echinostoma trivolvis are blood-feeding parasites. Nevertheless, there is no consensus on the feeding habits of the family Opisthorchiidae (Opisthorchis felineus, Opisthorchis viverrini and Clonorchis sinensis). Previously, histological studies of O. felineus and C. sinensis revealed some dark stained material in their gut lumen. In this study we conducted a comprehensive analysis of the gut contents of three members of the family Opisthorchiidae (O. felineus, O. viverrini and C. sinensis). Using transmission electron microscopy, we demonstrated for the first known time the presence of disintegrating blood cells in the gut of O. felineus as well as electron-dense crystals in the gut of O. felineus and C. sinensis. Electron energy loss spectroscopy revealed iron atoms in these crystals, and mass spectrometry of the purified pigment demonstrated the presence of heme. Fourier-transform infrared spectroscopy identified the signature peaks of the common iron-carboxylate bond characteristic in crystals isolated from O. felineus and C. sinensis. Scanning electron microscopy showed layered ovoid crystals of various sizes from 50 nm to 2 μm. Morphological, chemical and paramagnetic properties of these crystals were similar to those of hemozoin from Schistosoma mansoni. Crystal formation occurs on the surface of lipid droplets in O. felineus and C. sinensis guts. Our results suggest that the diet of O. felineus and C. sinensis includes blood. Detoxification of the free heme produced during the digestion proceeds via formation of insoluble crystals that contain iron and heme dimers, i.e. crystals of hemozoin. Furthermore, we believe that biocrystallisation of hemozoin takes place on the surface of the lipid droplets, similar to S. mansoni. Hemozoin was not detected in the closely related species O. viverrini.
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16
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Kuter D, Mohunlal R, Fitzroy SM, Asher C, Smith PJ, Egan TJ, de Villiers KA. Insights into the initial stages of lipid-mediated haemozoin nucleation. CrystEngComm 2016. [DOI: 10.1039/c6ce00866f] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
Abstract
Lipid-mediated haemozoin nucleation, as probed by molecular dynamics, proceeds via aggregation of ferrihaem π–π dimers at a lipid–aqueous interface.
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Affiliation(s)
- David Kuter
- Department of Chemistry and Polymer Science
- Stellenbosch University
- Matieland 7602, South Africa
| | - Roxanne Mohunlal
- Department of Chemistry
- University of Cape Town
- Rondebosch 7701, South Africa
| | - Sharné-Maré Fitzroy
- Department of Chemistry and Polymer Science
- Stellenbosch University
- Matieland 7602, South Africa
| | - Constance Asher
- Department of Chemistry
- University of Cape Town
- Rondebosch 7701, South Africa
| | - Peter J. Smith
- Division of Pharmacology
- Department of Medicine
- University of Cape Town Medical School
- Observatory 7925, South Africa
| | - Timothy J. Egan
- Department of Chemistry
- University of Cape Town
- Rondebosch 7701, South Africa
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17
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Stiebler R, Majerowicz D, Knudsen J, Gondim KC, Wright DW, Egan TJ, Oliveira MF. Unsaturated glycerophospholipids mediate heme crystallization: biological implications for hemozoin formation in the kissing bug Rhodnius prolixus. PLoS One 2014; 9:e88976. [PMID: 24586467 PMCID: PMC3935856 DOI: 10.1371/journal.pone.0088976] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/07/2013] [Accepted: 01/17/2014] [Indexed: 11/19/2022] Open
Abstract
Hemozoin (Hz) is a heme crystal produced by some blood-feeding organisms, as an efficient way to detoxify heme derived from hemoglobin digestion. In the triatomine insect Rhodnius prolixus, Hz is essentially produced by midgut extracellular phospholipid membranes known as perimicrovillar membranes (PMVM). Here, we investigated the role of commercial glycerophospholipids containing serine, choline and ethanolamine as headgroups and R. prolixus midgut lipids (RML) in heme crystallization. All commercial unsaturated forms of phospholipids, as well as RML, mediated fast and efficient β-hematin formation by means of two kinetically distinct mechanisms: an early and fast component, followed by a late and slow one. The fastest reactions observed were induced by unsaturated forms of phosphatidylethanolamine (uPE) and phosphatidylcholine (uPC), with half-lives of 0.04 and 0.7 minutes, respectively. β-hematin crystal morphologies were strikingly distinct among groups, with uPE producing homogeneous regular brick-shaped crystals. Interestingly, uPC-mediated reactions resulted in two morphologically distinct crystal populations: one less representative group of regular crystals, resembling those induced by uPE, and the other largely represented by crystals with numerous sharp edges and tapered ends. Heme crystallization reactions induced by RML were efficient, with a heme to β-hematin conversion rate higher than 70%, but clearly slower (t1/2 of 9.9-17.7 minutes) than those induced by uPC and uPE. Interestingly, crystals produced by RML were homogeneous in shape and quite similar to those mediated by uPE. Thus, β-hematin formation can be rapidly and efficiently induced by unsaturated glycerophospholipids, particularly uPE and uPC, and may play a role on biological heme crystallization in R. prolixus midgut.
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Affiliation(s)
- Renata Stiebler
- Laboratório de Bioquímica de Resposta ao Estresse, Instituto de Bioquímica Médica Leopoldo de Meis, Universidade Federal do Rio de Janeiro, RJ, Brazil
- Laboratório de Inflamação e Metabolismo, Instituto Nacional de Ciência e Tecnologia de Biologia Estrutural e Bioimagem, Universidade Federal do Rio de Janeiro, Rio de Janeiro, RJ, Brazil
- Department of Chemistry, Vanderbilt University, Nashville, Tennessee, United States of America
| | - David Majerowicz
- Laboratório de Bioquímica e Fisiologia de Insetos, Instituto de Bioquímica Médica Leopoldo de Meis, Universidade Federal do Rio de Janeiro, RJ, Brazil
- Department of Biochemistry and Molecular Biology, University of Southern Denmark, Odense, Denmark
- Departamento de Biotecnologia Farmacêutica, Faculdade de Farmácia,Universidade Federal do Rio de Janeiro, RJ, Brazil
| | - Jens Knudsen
- Department of Biochemistry and Molecular Biology, University of Southern Denmark, Odense, Denmark
| | - Katia C. Gondim
- Laboratório de Bioquímica e Fisiologia de Insetos, Instituto de Bioquímica Médica Leopoldo de Meis, Universidade Federal do Rio de Janeiro, RJ, Brazil
- Instituto Nacional de Ciência e Tecnologia em Entomologia Molecular, Rio de Janeiro, RJ, Brazil
| | - David W. Wright
- Department of Chemistry, Vanderbilt University, Nashville, Tennessee, United States of America
| | - Timothy J. Egan
- Department of Chemistry, University of Cape Town, Private Bag, Rondebosch, South Africa
| | - Marcus F. Oliveira
- Laboratório de Bioquímica de Resposta ao Estresse, Instituto de Bioquímica Médica Leopoldo de Meis, Universidade Federal do Rio de Janeiro, RJ, Brazil
- Laboratório de Inflamação e Metabolismo, Instituto Nacional de Ciência e Tecnologia de Biologia Estrutural e Bioimagem, Universidade Federal do Rio de Janeiro, Rio de Janeiro, RJ, Brazil
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18
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Characterization of a gene family encoding SEA (sea-urchin sperm protein, enterokinase and agrin)-domain proteins with lectin-like and heme-binding properties from Schistosoma japonicum. PLoS Negl Trop Dis 2014; 8:e2644. [PMID: 24416467 PMCID: PMC3886910 DOI: 10.1371/journal.pntd.0002644] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/24/2013] [Accepted: 11/28/2013] [Indexed: 11/23/2022] Open
Abstract
Background We previously identified a novel gene family dispersed in the genome of Schistosoma japonicum by retrotransposon-mediated gene duplication mechanism. Although many transcripts were identified, no homolog was readily identifiable from sequence information. Methodology/Principal Findings Here, we utilized structural homology modeling and biochemical methods to identify remote homologs, and characterized the gene products as SEA (sea-urchin sperm protein, enterokinase and agrin)-domain containing proteins. A common extracellular domain in this family was structurally similar to SEA-domain. SEA-domain is primarily a structural domain, known to assist or regulate binding to glycans. Recombinant proteins from three members of this gene family specifically interacted with glycosaminoglycans with high affinity, with potential implication in ligand acquisition and immune evasion. Similar approach was used to identify a heme-binding site on the SEA-domain. The heme-binding mode showed heme molecule inserted into a hydrophobic pocket, with heme iron putatively coordinated to two histidine axial ligands. Heme-binding properties were confirmed using biochemical assays and UV-visible absorption spectroscopy, which showed high affinity heme-binding (KD = 1.605×10−6 M) and cognate spectroscopic attributes of hexa-coordinated heme iron. The native proteins were oligomers, antigenic, and are localized on adult worm teguments and gastrodermis; major host-parasite interfaces and site for heme detoxification and acquisition. Conclusions The results suggest potential role, at least in the nucleation step of heme crystallization (hemozoin formation), and as receptors for heme uptake. Survival strategies exploited by parasites, including heme homeostasis mechanism in hemoparasites, are paramount for successful parasitism. Thus, assessing prospects for application in disease intervention is warranted. While isolating membrane-bound and secreted proteins as targets for Schistosoma japonicum vaccine, we identified a novel potentially functional gene family which had originated by a gene duplication mechanism. Here, we integrated structural homology modeling and biochemical methods to show that this gene family encodes proteins with sea-urchin sperm protein, enterokinase and agrin (SEA) –domain, with heme-binding properties. Typical of SEA-structural domains, the characterized proteins specifically interacted with glycosaminoglycans (GAGs), with implication in ligand gathering and immune-evasion. Consistent with modeled heme-binding pocket, we observed high affinity heme-binding and spectroscopic attributes of hexa-coordinated heme iron. Localization of the native gene-products on adult worm tegument and gastrodermis, host interfaces for heme-sequestration and acquisition, suggests potential roles for this gene family in heme-detoxification and heme-iron uptake.
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19
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Ambele MA, Sewell BT, Cummings FR, Smith PJ, Egan TJ. Synthetic Hemozoin (β-Hematin) Crystals Nucleate at the Surface of Neutral Lipid Droplets that Control Their Sizes. CRYSTAL GROWTH & DESIGN 2013; 13:10.1021/cg4009416. [PMID: 24244110 PMCID: PMC3826461 DOI: 10.1021/cg4009416] [Citation(s) in RCA: 17] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/02/2023]
Abstract
Emulsions of monopalmitoylglycerol (MPG) and of a neutral lipid blend (NLB), consisting of MPG, monostearoylglycerol, dipalmitoylglycerol, dioleoylglycerol and dilineoylglycerol (4:2:1:1:1), the composition associated with hemozoin from the malaria parasite Plasmodium falciparum, have been used to mediate the formation of β-hematin microcrystals. Transmission electron microscopy (TEM), electron diffraction and electron spectroscopic imaging/electron energy loss spectroscopy (ESI/EELS) have been used to characterize both the lipid emulsion and β-hematin crystals. The latter have been compared with β-hematin formed at a pentanol/aqueous interface and with hemozoin both within P. falciparum parasites and extracted from the parasites. When lipid and ferriprotoporphyrin IX solutions in 1:9 v/v acetone/methanol were thoroughly pre-mixed either using an extruder or ultrasound, β-hematin crystals were found formed in intimate association with the lipid droplets. These crystals resembled hemozoin crystals, with prominent {100} faces. Lattice fringes in TEM indicated that these faces made contact with the lipid surface. The average length of these crystals was 0.62 times the average diameter of NLB droplets and their size distributions were statistically equivalent after 10 min incubation, suggesting that the lipid droplets also controlled the sizes of the crystals. This most closely resembles hemozoin formation in the helminth worm Schistosoma mansoni, while in P. falciparum, crystal formation appears to be associated with the much more gently curved digestive vacuole membrane which apparently leads to formation of much larger hemozoin crystals, similar to those formed at the flat pentanol-water interface.
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Affiliation(s)
- Melvin A. Ambele
- Department of Chemistry, University of Cape Town, Private Bag, Rondebosch 7701, South Africa
| | - B. Trevor Sewell
- Electron Microscope Unit, University of Cape Town, Private Bag, Rondebosch 7701, South Africa
| | - Franscious R. Cummings
- Electron Microscope Unit, University of Cape Town, Private Bag, Rondebosch 7701, South Africa
| | - Peter J. Smith
- Division of Clinical Pharmacology, Department of Medicine, University of Cape Town, Private Bag, Rondebosch 7701, South Africa
| | - Timothy J. Egan
- Department of Chemistry, University of Cape Town, Private Bag, Rondebosch 7701, South Africa
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20
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Phospholipid membrane-mediated hemozoin formation: the effects of physical properties and evidence of membrane surrounding hemozoin. PLoS One 2013; 8:e70025. [PMID: 23894579 PMCID: PMC3720957 DOI: 10.1371/journal.pone.0070025] [Citation(s) in RCA: 20] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/11/2013] [Accepted: 06/20/2013] [Indexed: 11/19/2022] Open
Abstract
Phospholipid membranes are thought to be one of the main inducers of hemozoin formation in Plasmodia and other blood-feeding parasites. The “membrane surrounding hemozoin” has been observed in infected cells but has not been observed in in vitro experiments. This study focused on observing the association of phospholipid membranes and synthetic β-hematin, which is chemically identical to hemozoin, and on a further exploration into the mechanism of phospholipid membrane-induced β-hematin formation. Our results showed that β-hematin formation was induced by phospholipids in the fluid phase but not in the gel phase. The ability of phospholipids to induce β-hematin formation was inversely correlated with gel-to-liquid phase transition temperatures, suggesting an essential insertion of heme into the hydrocarbon chains of the phospholipid membrane to form β-hematin. For this study, a cryogenic transmission electron microscope was used to achieve the first direct observation of the formation of a monolayer of phospholipid membrane surrounding β-hematin.
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21
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Thétiot-Laurent SAL, Boissier J, Robert A, Meunier B. Chemotherapie gegen Schistosomiasis. Angew Chem Int Ed Engl 2013. [DOI: 10.1002/ange.201208390] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/14/2023]
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22
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Thétiot-Laurent SAL, Boissier J, Robert A, Meunier B. Schistosomiasis chemotherapy. Angew Chem Int Ed Engl 2013; 52:7936-56. [PMID: 23813602 DOI: 10.1002/anie.201208390] [Citation(s) in RCA: 95] [Impact Index Per Article: 8.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/18/2012] [Indexed: 01/08/2023]
Abstract
After malaria, schistosomiasis (or bilharzia) is the second most prevalent disease in Africa, and is occurring in over 70 countries in tropical and subtropical regions. It is estimated that 600 million people are at risk of infection, 200 million people are infected, and at least 200,000 deaths per year are associated with the disease. All schistosome species are transmitted through contact with fresh water that is infested with free-swimming forms of the parasite, which is known as cercariae and produced by snails. When located in the blood vessels of the host, larval and adult schistosomes digest red cells to acquire amino acids for growth and development. Vaccine candidates have been unsuccessful up to now. Against such devastating parasitic disease, the antischistosomal arsenal is currently limited to a single drug, praziquantel, which has been used for more than 35 years. Because the question of the reduction of the activity of praziquantel was raised recently, it is thus urgent to create new and safe antischistosomal drugs that should be combined with praziquantel to develop efficient bitherapies.
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Affiliation(s)
- Sophie A-L Thétiot-Laurent
- Laboratoire de Chimie de Coordination du CNRS, 205 route de Narbonne, BP 44099, 31077 Toulouse cedex 4, France
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Schistosoma mansoni hemozoin modulates alternative activation of macrophages via specific suppression of Retnla expression and secretion. Infect Immun 2012; 81:133-42. [PMID: 23090958 DOI: 10.1128/iai.00701-12] [Citation(s) in RCA: 26] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022] Open
Abstract
The trematode Schistosoma mansoni is one of the etiological agents of schistosomiasis, a key neglected tropical disease responsible for an estimated annual loss of 70 million disability-adjusted life years. Hematophagy represents the primary nutrient acquisition pathway of this parasite, but digestion of hemoglobin also liberates toxic heme. Schistosomes detoxify heme via crystallization into hemozoin, which is subsequently regurgitated into the host's circulation. Here we demonstrate that during experimental schistosomiasis, hemozoin accumulating in the mouse liver is taken up by phagocytes at a time coincident with the development of the egg-induced T-helper 2 (Th2) granulomatous immune response. Furthermore, the uptake of hemozoin also coincides with the hepatic expression of markers of alternative macrophage activation. Alternatively activated macrophages are a key effector cell population associated with protection against schistosomiasis, making hemozoin well placed to play an important immunomodulatory role in this disease. To systematically explore this hypothesis, S. mansoni hemozoin was purified and added to in vitro bone marrow-derived macrophage cultures concurrently exposed to cytokines chosen to reflect the shifting state of macrophage activation in vivo. Macrophages undergoing interleukin-4 (IL-4)-induced alternative activation in the presence of hemozoin developed a phenotype specifically lacking in Retnla, a characteristic alternatively activated macrophage product associated with regulation of Th2 inflammatory responses. As such, in addition to its important detoxification role during hematophagy, we propose that schistosome hemozoin also provides a potent immunomodulatory function in the coevolved network of host-parasite relationships during schistosomiasis.
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Ambele MA, Egan TJ. Neutral lipids associated with haemozoin mediate efficient and rapid β-haematin formation at physiological pH, temperature and ionic composition. Malar J 2012; 11:337. [PMID: 23043460 PMCID: PMC3479076 DOI: 10.1186/1475-2875-11-337] [Citation(s) in RCA: 30] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/18/2012] [Accepted: 10/03/2012] [Indexed: 11/10/2022] Open
Abstract
Background The malaria parasite disposes of host-derived ferrihaem (iron(III)protoporphyrin IX, Fe(III)PPIX) by conversion to crystalline haemozoin in close association with neutral lipids. Lipids mediate synthetic haemozoin (β-haematin) formation very efficiently. However, the effect on reaction rates of concentrations of lipid, Fe(III)PPIX and physiologically relevant ions and biomolecules are unknown. Methods Lipid emulsions containing Fe(III)PPIX were prepared in aqueous medium (pH 4.8, 37°C) to mediate β-haematin formation. The reaction was quenched at various times and free Fe(III)PPIX measured colorimetrically as a pyridine complex and the kinetics and yields analysed. Products were also characterized by FTIR, TEM and electron diffraction. Autofluorescence was also used to monitor β-haematin formation by confocal microscopy. Results At fixed Fe(III)PPIX concentration, β-haematin yields remained constant with decreasing lipid concentration until a cut-off ratio was reached whereupon efficiency decreased dramatically. For the haemozoin-associated neutral lipid blend (NLB) and monopalmitoylglycerol (MPG), this occurred below a lipid/Fe(III)PPIX (L/H) ratio of 0.54. Rate constants were found to increase with L/H ratio above the cut-off. At 16 μM MPG, Fe(III)PPIX concentration could be raised until the L/H ratio reached the same ratio before a sudden decline in yield was observed. MPG-mediated β-haematin formation was relatively insensitive to biologically relevant cations (Na+, K+, Mg2+, Ca2+), or anions (H2PO4−, HCO3−, ATP, 2,3-diphosphoglycerate, glutathione). Confocal microscopy demonstrated β-haematin formation occurs in association with the lipid particles. Conclusions Kinetics of β-haematin formation have shown that haemozoin-associated neutral lipids alone are capable of mediating β-haematin formation at adequate rates under physiologically realistic conditions of ion concentrations to account for haemozoin formation.
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Affiliation(s)
- Melvin A Ambele
- Department of Chemistry, University of Cape Town, Private Bag, Rondebosch 7701, South Africa
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Lanfranchi DA, Cesar-Rodo E, Bertrand B, Huang HH, Day L, Johann L, Elhabiri M, Becker K, Williams DL, Davioud-Charvet E. Synthesis and biological evaluation of 1,4-naphthoquinones and quinoline-5,8-diones as antimalarial and schistosomicidal agents. Org Biomol Chem 2012; 10:6375-87. [PMID: 22777178 PMCID: PMC3423093 DOI: 10.1039/c2ob25812a] [Citation(s) in RCA: 49] [Impact Index Per Article: 4.1] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/21/2023]
Abstract
Improving the solubility of polysubstituted 1,4-naphthoquinone derivatives was achieved by introducing nitrogen in two different positions of the naphthoquinone core, at C-5 and at C-8 of menadione through a two-step, straightforward synthesis based on the regioselective hetero-Diels-Alder reaction. The antimalarial and the antischistosomal activities of these polysubstituted aza-1,4-naphthoquinone derivatives were evaluated and led to the selection of distinct compounds for antimalarial versus antischistosomal action. The Ag(II)-assisted oxidative radical decarboxylation of the phenyl acetic acids using AgNO(3) and ammonium peroxodisulfate was modified to generate the 3-picolinyl-menadione with improved pharmacokinetic parameters, high antimalarial effects and capacity to inhibit the formation of β-hematin.
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Affiliation(s)
- Don Antoine Lanfranchi
- European School of Chemistry, Polymers and Materials (ECPM) University of Strasbourg, UMR CNRS 7509, 25 Rue Becquerel, F-67087 Strasbourg, France. Fax: +33 (0)3 68 85 27 42; Tel: +33 3 68 85 26 20
| | - Elena Cesar-Rodo
- European School of Chemistry, Polymers and Materials (ECPM) University of Strasbourg, UMR CNRS 7509, 25 Rue Becquerel, F-67087 Strasbourg, France. Fax: +33 (0)3 68 85 27 42; Tel: +33 3 68 85 26 20
| | - Benoît Bertrand
- European School of Chemistry, Polymers and Materials (ECPM) University of Strasbourg, UMR CNRS 7509, 25 Rue Becquerel, F-67087 Strasbourg, France. Fax: +33 (0)3 68 85 27 42; Tel: +33 3 68 85 26 20
| | - Hsin-Hung Huang
- Department of Immunology/Microbiology, Rush University Medical Center, 1735 West Harrison Street, Chicago, IL 60612, USA
| | - Latasha Day
- Department of Immunology/Microbiology, Rush University Medical Center, 1735 West Harrison Street, Chicago, IL 60612, USA
| | - Laure Johann
- European School of Chemistry, Polymers and Materials (ECPM) University of Strasbourg, UMR CNRS 7509, 25 Rue Becquerel, F-67087 Strasbourg, France. Fax: +33 (0)3 68 85 27 42; Tel: +33 3 68 85 26 20
| | - Mourad Elhabiri
- European School of Chemistry, Polymers and Materials (ECPM) University of Strasbourg, UMR CNRS 7509, 25 Rue Becquerel, F-67087 Strasbourg, France. Fax: +33 (0)3 68 85 27 42; Tel: +33 3 68 85 26 20
| | - Katja Becker
- Interdisciplinary Research Center, Nutritional Biochemistry, Justus Liebig University Giessen, Heinrich-Buff-Ring 26–32, D-35392 Giessen, Germany
| | - David L. Williams
- Department of Immunology/Microbiology, Rush University Medical Center, 1735 West Harrison Street, Chicago, IL 60612, USA
| | - Elisabeth Davioud-Charvet
- European School of Chemistry, Polymers and Materials (ECPM) University of Strasbourg, UMR CNRS 7509, 25 Rue Becquerel, F-67087 Strasbourg, France. Fax: +33 (0)3 68 85 27 42; Tel: +33 3 68 85 26 20
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Orjih AU, Mathew TC, Cherian PT. Erythrocyte membranes convert monomeric ferriprotoporphyrin IX to β-hematin in acidic environment at malarial fever temperature. Exp Biol Med (Maywood) 2012; 237:884-93. [PMID: 22890028 DOI: 10.1258/ebm.2012.012013] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/18/2022] Open
Abstract
Hemozoin production makes it possible for intraerythrocytic malaria parasites to digest massive quantities of hemoglobin but still avoid potential ferriprotoporphyrin IX (FP) toxicity, which they cannot decompose further. Some antimalarial drugs, such as chloroquine, work by inhibiting this production, forcing the parasite to starve to death. As part of the efforts to identify possible biological mechanisms of FP polymerization, we have used normal human erythrocyte membranes as a model, to promote β-hematin (β-h) synthesis. Hemin in 35% aqueous dimethyl sulfoxide (DMSO) was reacted with isolated erythrocyte membranes and incubated overnight in sodium acetate buffer, pH 4.8, at 41°C. Infrared spectroscopy and electron microscopy showed that β-h was produced. Hemin in 10% was less effective as the substrate than when it was in 35% DMSO. A high malarial temperature seemed to be necessary, because FP polymerization was less at 37°C than at 41°C. Production was partially inhibited by chloroquine. These observations are of interest because other investigators have reported that membrane lipids mediated FP polymerization, but whole membranes were ineffective. On the other hand, our hypothesis is that the transport vesicles (TV) in malaria parasites could provide the receptor for FP and the lipids that promote hemozoin formation. Erythrocyte membranes may not be directly involved, but Plasmodium species transport hemoglobin in membrane-bound TV into food vacuoles, where hemoglobin catabolism is completed and hemozoin crystals are stored.
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Affiliation(s)
- Augustine U Orjih
- Department of Medical Laboratory Sciences, Kuwait University, Kuwait, Arabian Gulf.
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Hamza I, Dailey HA. One ring to rule them all: trafficking of heme and heme synthesis intermediates in the metazoans. BIOCHIMICA ET BIOPHYSICA ACTA-MOLECULAR CELL RESEARCH 2012; 1823:1617-32. [PMID: 22575458 DOI: 10.1016/j.bbamcr.2012.04.009] [Citation(s) in RCA: 167] [Impact Index Per Article: 13.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/13/2012] [Revised: 04/15/2012] [Accepted: 04/19/2012] [Indexed: 12/17/2022]
Abstract
The appearance of heme, an organic ring surrounding an iron atom, in evolution forever changed the efficiency with which organisms were able to generate energy, utilize gasses and catalyze numerous reactions. Because of this, heme has become a near ubiquitous compound among living organisms. In this review we have attempted to assess the current state of heme synthesis and trafficking with a goal of identifying crucial missing information, and propose hypotheses related to trafficking that may generate discussion and research. The possibilities of spatially organized supramolecular enzyme complexes and organelle structures that facilitate efficient heme synthesis and subsequent trafficking are discussed and evaluated. Recently identified players in heme transport and trafficking are reviewed and placed in an organismal context. Additionally, older, well established data are reexamined in light of more recent studies on cellular organization and data available from newer model organisms. This article is part of a Special Issue entitled: Cell Biology of Metals.
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Affiliation(s)
- Iqbal Hamza
- Department of Animal & Avian Sciences, University of Maryland, College Park, MD 20742, USA.
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Stiebler R, Soares JBRC, Timm BL, Silva JR, Mury FB, Dansa-Petretski M, Oliveira MF. On the mechanisms involved in biological heme crystallization. J Bioenerg Biomembr 2011; 43:93-9. [PMID: 21301942 DOI: 10.1007/s10863-011-9335-x] [Citation(s) in RCA: 18] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Abstract
Blood-feeding organisms digest hemoglobin, releasing large quantities of heme inside their digestive tracts. Free heme is very toxic, and these organisms have evolved several mechanisms to protect against its deleterious effects. One of these adaptations is the crystallization of heme into the dark-brown pigment hemozoin (Hz). Here we review the process of Hz formation, focusing on organisms other than Plasmodium that have contributed to a better understanding of heme crystallization. Hemozoin has been found in several distinct classes of organisms including protozoa, helminths and insects and Hz formation is the predominant form of heme detoxification. The available evidence indicates that amphiphilic structures such as phospholipid membranes and lipid droplets accompanied by specific proteins play a major role in heme crystallization. Because this process is specific to a number of blood-feeding organisms and absent in their hosts, Hz formation is an attractive target for the development of novel drugs to control illnesses associated with these hematophagous organisms.
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Affiliation(s)
- Renata Stiebler
- Instituto de Bioquímica Médica, Universidade Federal do Rio de Janeiro, Rio de Janeiro, Rio de Janeiro, Brazil
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Increase on the initial soluble heme levels in acidic conditions is an important mechanism for spontaneous heme crystallization in vitro. PLoS One 2010; 5:e12694. [PMID: 20856937 PMCID: PMC2938344 DOI: 10.1371/journal.pone.0012694] [Citation(s) in RCA: 21] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/21/2009] [Accepted: 08/06/2010] [Indexed: 11/19/2022] Open
Abstract
BACKGROUND Hemozoin (Hz) is a heme crystal that represents a vital pathway for heme disposal in several blood-feeding organisms. Recent evidence demonstrated that β-hematin (βH) (the synthetic counterpart of Hz) formation occurs under physiological conditions near synthetic or biological hydrophilic-hydrophobic interfaces. This seems to require a heme dimer acting as a precursor of Hz crystals that would be formed spontaneously in the absence of the competing water molecules bound to the heme iron. Here, we aimed to investigate the role of medium polarity on spontaneous βH formation in vitro. METHODOLOGY/PRINCIPAL FINDINGS We assessed the effect of water content on spontaneous βH formation by using the aprotic solvent dimethylsulfoxide (DMSO) and a series of polyethyleneglycols (PEGs). We observed that both DMSO and PEGs (3.350, 6.000, 8.000, and 22.000) increased the levels of soluble heme under acidic conditions. These compounds were able to stimulate the production of βH crystals in the absence of any biological sample. Interestingly, the effects of DMSO and PEGs on βH formation were positively correlated with their capacity to promote previous heme solubilization in acidic conditions. Curiously, a short chain polyethyleneglycol (PEG 300) caused a significant reduction in both soluble heme levels and βH formation. Finally, both heme solubilization and βH formation strongly correlated with reduced medium water activity provided by increased DMSO concentrations. CONCLUSIONS The data presented here support the notion that reduction of the water activity is an important mechanism to support spontaneous heme crystallization, which depends on the previous increase of soluble heme levels.
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Stiebler R, Timm BL, Oliveira PL, Hearne GR, Egan TJ, Oliveira MF. On the physico-chemical and physiological requirements of hemozoin formation promoted by perimicrovillar membranes in Rhodnius prolixus midgut. INSECT BIOCHEMISTRY AND MOLECULAR BIOLOGY 2010; 40:284-292. [PMID: 20060043 DOI: 10.1016/j.ibmb.2009.12.013] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/29/2009] [Revised: 12/21/2009] [Accepted: 12/22/2009] [Indexed: 05/28/2023]
Abstract
Triatomine insects are obligatory blood-feeders that detoxify most of the hemoglobin-derived heme through its crystallization into hemozoin (Hz). Previous evidence demonstrates the key role of midgut perimicrovillar membranes (PMVM) on heme crystallization in triatomines. Here, we investigated some of the physico-chemical and physiological aspects of heme crystallization induced by Rhodnius prolixus PMVM. Hz formation in vitro proceeded optimally at pH 4.8 and 28 degrees C, apparently involving three kinetically distinct mechanisms along this process. Furthermore, the insect feeding status and age affected PMVM-induced heme crystallization whereas pharmacological blockage of PMVM formation by azadirachtin, reduced hemoglobin digestion and Hz formation in vivo. Mössbauer spectrometry analyses of R. prolixus midgut showed that Hz represents the only measurable iron species found four days after a blood meal. Autocatalytic heme crystallization to Hz is revealed to be an inefficient process and this conversion is further reduced as the Hz concentration increases. Also, PMVM-derived lipids were able to induce rapid Hz formation, regardless of the diet composition. These results indicate that PMVM-driven Hz formation in R. prolixus midgut occurs at physiologically relevant physico-chemical conditions and that lipids derived from this structure play an important role in heme crystallization.
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Affiliation(s)
- Renata Stiebler
- Laboratório de Bioquímica Redox, Programa de Biologia Molecular e Biotecnologia, Instituto de Bioquímica Médica, Universidade Federal do Rio de Janeiro, Rio de Janeiro, RJ, Brazil
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Bozza PT, D’Avila H, Almeida PE, Magalhães KG, Molinaro R, Almeida CJ, Maya-Monteiro CM. Lipid droplets in host–pathogen interactions. ACTA ACUST UNITED AC 2009. [DOI: 10.2217/clp.09.63] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/23/2022]
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Hoang AN, Ncokazi KK, de Villiers KA, Wright DW, Egan TJ. Crystallization of synthetic haemozoin (beta-haematin) nucleated at the surface of lipid particles. Dalton Trans 2009; 39:1235-44. [PMID: 20104349 DOI: 10.1039/b914359a] [Citation(s) in RCA: 57] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
Abstract
The mechanism of formation of haemozoin, a detoxification by-product of several blood-feeding organisms including malaria parasites, has been a subject of debate; however, recent studies suggest that neutral lipids may serve as a catalyst. In this study, a model system consisting of an emulsion of neutral lipid particles was employed to investigate the formation of beta-haematin, the synthetic counterpart of haemozoin, at the lipid-water interface. A solution of monoglyceride, either monostearoylglycerol (MSG) or monopalmitoylglycerol (MPG), dissolved in acetone and methanol was introduced to an aqueous surface. Fluorescence, confocal and transmission electron microscopic (TEM) imaging and dynamic light scattering analysis of samples obtained from beneath the surface confirmed the presence of homogeneous lipid particles existing in two major populations: one in the low micrometre size range and the other in the hundred nanometre range. The introduction of haem (Fe(iii)PPIX) to this lipid particle system under biomimetic conditions (37 degrees C, pH 4.8) produced beta-haematin with apparent first-order kinetics and an average half life of 0.5 min. TEM of monoglycerides (MSG or MPG) extruded through a 200 nm filter with haem produced beta-haematin crystals aligned and parallel to the lipid-water interface. These TEM data, together with a model system replacing the lipid with an aqueous organic solvent interface using either methyl laurate or docosane demonstrated that the OH and C[double bond, length as m-dash]O groups are apparently necessary for efficient nucleation. This suggests that beta-haematin crystallizes via epitaxial nucleation at the lipid-water interface through interaction of Fe(iii)PPIX with the polar head group. Once nucleated, the crystal grows parallel to the interface until growth is terminated by the curvature of the lipid particle. The hydrophobic nature of the mature crystal favours an interior transport resulting in crystals aligned parallel to the lipid-water interface and each other, strikingly similar to that seen in malaria parasites.
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Affiliation(s)
- Anh N Hoang
- Department of Chemistry, Vanderbilt University, Station B351822, Nashville, TN 37235, USA
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Corrêa Soares JBR, Menezes D, Vannier-Santos MA, Ferreira-Pereira A, Almeida GT, Venancio TM, Verjovski-Almeida S, Zishiri VK, Kuter D, Hunter R, Egan TJ, Oliveira MF. Interference with hemozoin formation represents an important mechanism of schistosomicidal action of antimalarial quinoline methanols. PLoS Negl Trop Dis 2009; 3:e477. [PMID: 19597543 PMCID: PMC2703804 DOI: 10.1371/journal.pntd.0000477] [Citation(s) in RCA: 62] [Impact Index Per Article: 4.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/19/2009] [Accepted: 06/03/2009] [Indexed: 01/27/2023] Open
Abstract
BACKGROUND The parasitic trematode Schistosoma mansoni is one of the major causative agents of human schistosomiasis, which afflicts 200 million people worldwide. Praziquantel remains the main drug used for schistosomiasis treatment, and reliance on the single therapy has been prompting the search for new therapeutic compounds against this disease. Our group has demonstrated that heme crystallization into hemozoin (Hz) within the S. mansoni gut is a major heme detoxification route with lipid droplets involved in this process and acting as a potential chemotherapeutical target. In the present work, we investigated the effects of three antimalarial compounds, quinine (QN), quinidine (QND) and quinacrine (QCR) in a murine schistosomiasis model by using a combination of biochemical, cell biology and molecular biology approaches. METHODOLOGY/PRINCIPAL FINDINGS Treatment of S. mansoni-infected female Swiss mice with daily intraperitoneal injections of QN, and QND (75 mg/kg/day) from the 11(th) to 17(th) day after infection caused significant decreases in worm burden (39%-61%) and egg production (42%-98%). Hz formation was significantly inhibited (40%-65%) in female worms recovered from QN- and QND-treated mice and correlated with reduction in the female worm burden. We also observed that QN treatment promoted remarkable ultrastructural changes in male and female worms, particularly in the gut epithelium and reduced the granulomatous reaction to parasite eggs trapped in the liver. Microarray gene expression analysis indicated that QN treatment increased the expression of transcripts related to musculature, protein synthesis and repair mechanisms. CONCLUSIONS The overall significant reduction in several disease burden parameters by the antimalarial quinoline methanols indicates that interference with Hz formation in S. mansoni represents an important mechanism of schistosomicidal action of these compounds and points out the heme crystallization process as a valid chemotherapeutic target to treat schistosomiasis.
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Affiliation(s)
- Juliana B. R. Corrêa Soares
- Laboratório de Bioquímica Redox, Programa de Biologia Molecular e Biotecnologia, Instituto de Bioquímica Médica, Universidade Federal do Rio de janeiro, Rio de Janeiro, Brazil
| | | | | | - Antonio Ferreira-Pereira
- Departamento de Microbiologia Geral, Instituto de Microbiologia Prof. Paulo de Góes, Universidade Federal do Rio de Janeiro, Rio de Janeiro, Brazil
| | - Giulliana T. Almeida
- Departamento de Bioquímica, Instituto de Química, Universidade de São Paulo, São Paulo, Brazil
| | - Thiago M. Venancio
- Departamento de Bioquímica, Instituto de Química, Universidade de São Paulo, São Paulo, Brazil
| | | | - Vincent K. Zishiri
- Department of Chemistry, University of Cape Town, Rondebosch, Cape Town, South Africa
| | - David Kuter
- Department of Chemistry, University of Cape Town, Rondebosch, Cape Town, South Africa
| | - Roger Hunter
- Department of Chemistry, University of Cape Town, Rondebosch, Cape Town, South Africa
| | - Timothy J. Egan
- Department of Chemistry, University of Cape Town, Rondebosch, Cape Town, South Africa
| | - Marcus F. Oliveira
- Laboratório de Bioquímica Redox, Programa de Biologia Molecular e Biotecnologia, Instituto de Bioquímica Médica, Universidade Federal do Rio de janeiro, Rio de Janeiro, Brazil
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Bibliography. Current world literature. Atherosclerosis: cell biology and lipoproteins. Curr Opin Lipidol 2008; 19:525-35. [PMID: 18769235 DOI: 10.1097/mol.0b013e328312bffc] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 10/21/2022]
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Lipid bodies in innate immune response to bacterial and parasite infections. Int Immunopharmacol 2008; 8:1308-15. [DOI: 10.1016/j.intimp.2008.01.035] [Citation(s) in RCA: 57] [Impact Index Per Article: 3.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/29/2007] [Accepted: 01/02/2008] [Indexed: 01/06/2023]
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Martínez A, Rajapakse CSK, Naoulou B, Kopkalli Y, Davenport L, Sánchez-Delgado RA. The mechanism of antimalarial action of the ruthenium(II)-chloroquine complex [RuCl(2)(CQ)] (2). J Biol Inorg Chem 2008; 13:703-12. [PMID: 18305967 PMCID: PMC2409194 DOI: 10.1007/s00775-008-0356-9] [Citation(s) in RCA: 26] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/09/2008] [Accepted: 02/18/2008] [Indexed: 10/22/2022]
Abstract
The mechanism of antimalarial action of the ruthenium-chloroquine complex [RuCl(2)(CQ)](2) (1), previously shown by us to be active in vitro against CQ-resistant strains of Plasmodium falciparum and in vivo against P. berghei, has been investigated. The complex is rapidly hydrolyzed in aqueous solution to [RuCl(OH(2))(3)(CQ)](2)[Cl](2), which is probably the active species. This compound binds to hematin in solution and inhibits aggregation to beta-hematin at pH approximately 5 to a slightly lower extent than chloroquine diphosphate; more importantly, the heme aggregation inhibition activity of complex 1 is significantly higher than that of CQ when measured at the interface of n-octanol-aqueous acetate buffer mixtures under acidic conditions modeling the food vacuole of the parasite. Partition coefficient measurements confirmed that complex 1 is considerably more lipophilic than CQ in n-octanol-water mixtures at pH approximately 5. This suggests that the principal target of complex 1 is the heme aggregation process, which has recently been reported to be fast and spontaneous at or near water-lipid interfaces. The enhanced antimalarial activity of complex 1 is thus probably due to a higher effective concentration of the drug at or near the interface compared with that of CQ, which accumulates strongly in the aqueous regions of the vacuole under those conditions. Furthermore, the activity of complex 1 against CQ-resistant strains of P. falciparum is probably related to its greater lipophilicity, in line with previous reports indicating a lowered ability of the mutated transmembrane transporter PfCRT to promote the efflux of highly lipophilic drugs. The metal complex also interacts with DNA by intercalation, to a comparable extent and in a similar manner to uncomplexed CQ and therefore DNA binding does not appear to be an important part of the mechanism of antimalarial action in this case.
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Affiliation(s)
- Alberto Martínez
- Chemistry Department, Brooklyn College and The Graduate Center, The City University of New York, 2900 Bedford Avenue, Brooklyn, NY, 11210, USA
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Egan TJ. Recent advances in understanding the mechanism of hemozoin (malaria pigment) formation. J Inorg Biochem 2008; 102:1288-99. [DOI: 10.1016/j.jinorgbio.2007.12.004] [Citation(s) in RCA: 136] [Impact Index Per Article: 8.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/07/2007] [Revised: 10/19/2007] [Accepted: 10/31/2007] [Indexed: 11/15/2022]
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Haemozoin formation. Mol Biochem Parasitol 2008; 157:127-36. [DOI: 10.1016/j.molbiopara.2007.11.005] [Citation(s) in RCA: 151] [Impact Index Per Article: 9.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/15/2007] [Revised: 11/05/2007] [Accepted: 11/06/2007] [Indexed: 11/18/2022]
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Glanfield A, McManus DP, Anderson GJ, Jones MK. Pumping iron: a potential target for novel therapeutics against schistosomes. Trends Parasitol 2007; 23:583-8. [PMID: 17962074 PMCID: PMC2756500 DOI: 10.1016/j.pt.2007.08.018] [Citation(s) in RCA: 33] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/15/2007] [Revised: 02/13/2007] [Accepted: 08/06/2007] [Indexed: 11/17/2022]
Abstract
Parasites, as with the vast majority of organisms, are dependent on iron. Pathogens must compete directly with the host for this essential trace metal, which is sequestered within host proteins and inorganic chelates. Not surprisingly, pathogenic prokaryotes and eukaryotic parasites have diverse adaptations to exploit host iron resources. How pathogenic bacteria scavenge host iron is well characterized and is reasonably well known for a few parasitic protozoa, but is poorly understood for metazoan parasites. Strategies of iron acquisition by schistosomes are examined here, with emphasis on possible mechanisms of iron absorption from host serum iron transporters or from digested haem. Elucidation of these metabolic mechanisms could lead to the development of new interventions for the control of schistosomiasis and other helminth diseases.
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Affiliation(s)
- Amber Glanfield
- Division of Infectious Diseases and Immunology, The Queensland Institute of Medical Research, 300 Herston Road, Herston, Queensland 4006, Australia.
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Hemozoin: oil versus water. Parasitol Int 2007; 57:89-96. [PMID: 18373972 DOI: 10.1016/j.parint.2007.09.009] [Citation(s) in RCA: 46] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/23/2007] [Revised: 09/26/2007] [Accepted: 09/28/2007] [Indexed: 11/23/2022]
Abstract
Because the quinolines inhibit heme crystallization within the malaria parasite much work has focused on mechanism of formation and inhibition of hemozoin. Here we review the recent evidence for heme crystallization within lipids in diverse parasites and the new implications of a lipid site of crystallization for drug targeting. Within leukocytes hemozoin can generate toxic radical lipid metabolites, which may alter immune function or reduce deformability of uninfected erythrocytes.
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Carter MD, Harry SR, Wright DW. Identification of hydroxyeicosatetraenoic acid components of schistosomal hemozoin. Biochem Biophys Res Commun 2007; 363:867-72. [PMID: 17904531 PMCID: PMC2705926 DOI: 10.1016/j.bbrc.2007.09.051] [Citation(s) in RCA: 11] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/15/2007] [Accepted: 09/14/2007] [Indexed: 11/29/2022]
Abstract
During the late stages of Schistosoma mansoni infection, adult schistosomes catabolize host erythrocytic hemoglobin. In order to evade the toxic effects of free heme, the blood fluke biomineralizes dimeric heme into an inert crystalline pigment called hemozoin. In the present study, the chemical reactivity of schistosomal hemozoin (SmHz) toward lipid oxidation was examined, and the biological consequences of reactivity were investigated. Mass spectrometric analysis of polar lipid content associated with SmHz identified a variety of primary and secondary polyunsaturated fatty acid oxidation products, including hydroxyeicosatetraenoic acids. Furthermore, RAW 264.7 macrophage-like cells challenged with lipopolysaccharide prior to phagocytosis of SmHz experienced a decrease in nitric oxide production as compared to control experiments. The presence of these biologically active oxidation products suggests native SmHz is capable of modulating the innate immune response and may play a potential role in the pathogenesis of schistosomiasis.
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Affiliation(s)
| | | | - David W. Wright
- Corresponding author. Fax: +1 615 343 1234, Email address: (D. W. Wright)
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Caffrey CR. Chemotherapy of schistosomiasis: present and future. Curr Opin Chem Biol 2007; 11:433-9. [PMID: 17652008 DOI: 10.1016/j.cbpa.2007.05.031] [Citation(s) in RCA: 209] [Impact Index Per Article: 12.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/04/2007] [Revised: 05/23/2007] [Accepted: 05/29/2007] [Indexed: 12/12/2022]
Abstract
Schistosomiasis is a chronic parasitic disease in tropical and subtropical regions and is associated with a variety of clinical syndromes that may lead to severe morbidity. Over the past 25 years, therapy and control of schistosomiasis has come to rely heavily on one drug, praziquantel (PZQ). This reliance is of concern should widespread treatment failure arise, particularly as measures are being undertaken to increase PZQ's availability. This review summarizes the use, possible modes of action and limitations of PZQ, and recent attempts to derive synthetic analogs. Alternative artemisinin-based chemotherapies that have shown applicability in certain disease settings are also similarly examined. Looking forward, the review highlights some of the more experimental anti-schistosomals being evaluated (e.g. the trioxolanes), including those where knowledge of the parasite target (e.g. cysteine proteases and hemozoin formation) is more defined.
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Affiliation(s)
- Conor R Caffrey
- Sandler Center for Basic Research in Parasitic Diseases, Byers Hall N508, University of California San Francisco, 1700 4th Street, San Francisco, CA 94158-2330, United States.
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