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Muya K, Kalonji M, Kaponda A, Kaut M, Mboni MA, Wa Ilunga N, Kitambala M, Kamulete S, Amuri B, Mutombo K, Simbi L. [Acute and subacute toxicity of Garcinia huillensis Baker, a plant used against urogenital schistosomiasis in Haut-Katanga, DR Congo]. ANNALES PHARMACEUTIQUES FRANÇAISES 2020; 79:308-323. [PMID: 33309607 DOI: 10.1016/j.pharma.2020.11.006] [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: 04/21/2020] [Revised: 11/24/2020] [Accepted: 11/30/2020] [Indexed: 11/19/2022]
Abstract
This research evaluated acute and subacute toxicity of aqueous and methanolic extract from stem bark of Garcinia huillensis Baker, a plant used in Congolese traditional medicine against urogenital schistosomiasis. The acute toxicity is evaluated on guinea pigs by single oral administration of 1500, 2000, 2500, 3000 and 3500mg/kg of body weight of extracts based on the method described by protocol 423 of the Organization for Cooperation and Economic Development. Subacute toxicity is assessed after 28 days after daily administration of 4.5, 45, 450 and 1500mg/kg of body weight of extracts. Weight evolution, hematological and biochemical parameters of the guinea pigs that survived were analyzed and compared with those of the controls. Acute oral toxicity data were used to calculate the LD50 of 2717.39 and 2625.00mg/kg bw for the aqueous and methanolic extract, respectively. Some signs of intoxication were noted, and certain haematological and biochemical parameters analyzed in the treated guinea pigs sometimes presented statistically significant differences compared to those of the controls. The minimum tolerated dose (1652.17mg/kg bw) found for the aqueous extract is far greater than the therapeutic dose administered by traditional therapists (4.5mg). Thus, the study shows that the stem bark of G. huillensis would be moderately toxic and would present a good margin of safety under the conditions of our experimentation, which would justify the non-toxic use of the plant under the traditional conditions of preparation and oral administration.
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Affiliation(s)
- K Muya
- Laboratoire de pharmacognosie, faculté des sciences pharmaceutiques, université de Lubumbashi (UNILU), 27, avenue Kato, Commune Kampemba, Lubumbashi, République démocratique du Congo.
| | - M Kalonji
- Laboratoire de pharmacognosie, faculté des sciences pharmaceutiques, université de Lubumbashi (UNILU), 27, avenue Kato, Commune Kampemba, Lubumbashi, République démocratique du Congo
| | - A Kaponda
- Laboratoire de biologie clinique, faculté des sciences pharmaceutiques, UNILU, 27, avenue Kato, Commune Kampemba, Lubumbashi, République démocratique du Congo
| | - M Kaut
- École de santé publique, UNILU, 57, avenue Ndjamena, Commune Lubumbashi, Lubumbashi, République démocratique du Congo
| | - M A Mboni
- Laboratoire de pharmacognosie, faculté des sciences pharmaceutiques, université de Lubumbashi (UNILU), 27, avenue Kato, Commune Kampemba, Lubumbashi, République démocratique du Congo
| | - N Wa Ilunga
- Laboratoire de pharmacognosie, faculté des sciences pharmaceutiques, université de Lubumbashi (UNILU), 27, avenue Kato, Commune Kampemba, Lubumbashi, République démocratique du Congo
| | - M Kitambala
- Laboratoire de chimie organique, faculté des sciences, université de Lubumbashi, 02, avenue de la Maternité, Commune Lubumbashi, Lubumbashi, République démocratique du Congo
| | - S Kamulete
- Laboratoire de pharmacognosie, faculté des sciences pharmaceutiques, université de Lubumbashi (UNILU), 27, avenue Kato, Commune Kampemba, Lubumbashi, République démocratique du Congo
| | - B Amuri
- Laboratoire de pharmacognosie, faculté des sciences pharmaceutiques, université de Lubumbashi (UNILU), 27, avenue Kato, Commune Kampemba, Lubumbashi, République démocratique du Congo
| | - K Mutombo
- Laboratoire de chimie organique, faculté des sciences, université de Lubumbashi, 02, avenue de la Maternité, Commune Lubumbashi, Lubumbashi, République démocratique du Congo
| | - L Simbi
- Laboratoire de chimie organique, faculté des sciences, université de Lubumbashi, 02, avenue de la Maternité, Commune Lubumbashi, Lubumbashi, République démocratique du Congo
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Khan D, Lee D, Gulten G, Aggarwal A, Wofford J, Krieger I, Tripathi A, Patrick JW, Eckert DM, Laganowsky A, Sacchettini J, Lindahl P, Bankaitis VA. A Sec14-like phosphatidylinositol transfer protein paralog defines a novel class of heme-binding proteins. eLife 2020; 9:57081. [PMID: 32780017 PMCID: PMC7462610 DOI: 10.7554/elife.57081] [Citation(s) in RCA: 9] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/20/2020] [Accepted: 08/10/2020] [Indexed: 01/02/2023] Open
Abstract
Yeast Sfh5 is an unusual member of the Sec14-like phosphatidylinositol transfer protein (PITP) family. Whereas PITPs are defined by their abilities to transfer phosphatidylinositol between membranes in vitro, and to stimulate phosphoinositide signaling in vivo, Sfh5 does not exhibit these activities. Rather, Sfh5 is a redox-active penta-coordinate high spin FeIII hemoprotein with an unusual heme-binding arrangement that involves a co-axial tyrosine/histidine coordination strategy and a complex electronic structure connecting the open shell iron d-orbitals with three aromatic ring systems. That Sfh5 is not a PITP is supported by demonstrations that heme is not a readily exchangeable ligand, and that phosphatidylinositol-exchange activity is resuscitated in heme binding-deficient Sfh5 mutants. The collective data identify Sfh5 as the prototype of a new class of fungal hemoproteins, and emphasize the versatility of the Sec14-fold as scaffold for translating the binding of chemically distinct ligands to the control of diverse sets of cellular activities.
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Affiliation(s)
- Danish Khan
- Department of Biochemistry and Biophysics, Texas A&M University, College Station, United States
| | - Dongju Lee
- Department of Molecular and Cellular Medicine, Texas A&M Health Sciences Center, College Station, United States
| | - Gulcin Gulten
- Department of Biochemistry and Biophysics, Texas A&M University, College Station, United States
| | - Anup Aggarwal
- Department of Biochemistry and Biophysics, Texas A&M University, College Station, United States
| | - Joshua Wofford
- Department of Chemistry, Texas A&M University, College Station, United States.,Department of Chemistry, Charleston Southern University, North Charleston, United States
| | - Inna Krieger
- Department of Biochemistry and Biophysics, Texas A&M University, College Station, United States
| | - Ashutosh Tripathi
- Department of Molecular and Cellular Medicine, Texas A&M Health Sciences Center, College Station, United States
| | - John W Patrick
- Department of Chemistry, Texas A&M University, College Station, United States
| | - Debra M Eckert
- Department of Biochemistry, University of Utah School of Medicine, Salt Lake City, United States
| | - Arthur Laganowsky
- Department of Chemistry, Texas A&M University, College Station, United States
| | - James Sacchettini
- Department of Biochemistry and Biophysics, Texas A&M University, College Station, United States
| | - Paul Lindahl
- Department of Biochemistry and Biophysics, Texas A&M University, College Station, United States.,Department of Chemistry, Texas A&M University, College Station, United States
| | - Vytas A Bankaitis
- Department of Biochemistry and Biophysics, Texas A&M University, College Station, United States.,Department of Molecular and Cellular Medicine, Texas A&M Health Sciences Center, College Station, United States.,Department of Chemistry, Texas A&M University, College Station, United States
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Chutshela A, Masamba P, Oyinloye BE, Kappo AP. Molecular Context of ADP-ribosylation in Schistosomes for Drug Discovery and Vaccine Development. Curr Drug Discov Technol 2020; 18:473-484. [PMID: 32767945 DOI: 10.2174/1570163817666200806170654] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/11/2020] [Revised: 07/06/2020] [Accepted: 07/06/2020] [Indexed: 11/22/2022]
Abstract
Schistosome infection is regarded as one of the most important and neglected tropical diseases associated with poor sanitation. Like other living organisms, schistosomes employ multiple biological processes, of which some are regulated by a post-translational modification called Adenosine Diphosphate-ribosylation (ADP-ribosylation), catalyzed by ADP-ribosyltransferases. ADP-ribosylation is the addition of ADP-ribose moieties from Nicotinamide Adenine Dinucleotide (NAD+) to various targets, which include proteins and nucleotides. It is crucial in biological processes such as DNA repair, apoptosis, carbohydrate metabolism and catabolism. In the absence of a vaccine against schistosomiasis, this becomes a promising pathway in the identification of drug targets against various forms of this infection. The tegument of the worm is an encouraging immunogenic target for anti-schistosomal vaccine development. Vaccinology, molecular modeling and target-based drug discovery strategies have been used for years in drug discovery and for vaccine development. In this paper, we outline ADP-ribosylation and other different approaches to drug discovery and vaccine development against schistosomiasis.
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Affiliation(s)
- Amandla Chutshela
- Department of Biochemistry and Microbiology, University of Zululand, KwaDlangezwa 3886, South Africa
| | - Priscilla Masamba
- Molecular Biophysics and Structural Biology Group, Department of Biochemistry, University of Johannesburg, Kingsway Campus, Auckland Park 2006, South Africa
| | | | - Abidemi Paul Kappo
- Molecular Biophysics and Structural Biology Group, Department of Biochemistry, University of Johannesburg, Kingsway Campus, Auckland Park 2006, South Africa
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Thomas CM, Timson DJ. The Mechanism of Action of Praziquantel: Can New Drugs Exploit Similar Mechanisms? Curr Med Chem 2020; 27:676-696. [DOI: 10.2174/0929867325666180926145537] [Citation(s) in RCA: 21] [Impact Index Per Article: 5.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/27/2017] [Revised: 04/06/2018] [Accepted: 08/20/2018] [Indexed: 11/22/2022]
Abstract
Praziquantel (PZQ) is the drug of choice for treating infection with worms from the
genus Schistosoma. The drug is effective, cheap and has few side effects. However, despite its
use in millions of patients for over 40 years its molecular mechanism of action remains elusive.
Early studies demonstrated that PZQ disrupts calcium ion homeostasis in the worm and
the current consensus is that it antagonises voltage-gated calcium channels. It is hypothesised
that disruption of these channels results in uncontrolled calcium ion influx leading to uncontrolled
muscle contraction and paralysis. However, other experimental studies have suggested
a role for myosin regulatory light chains and adenosine uptake in the drug’s mechanism of
action. Assuming voltage-gated calcium channels do represent the main molecular target of
PZQ, the precise binding site for the drug remains to be identified. Unlike other commonly
used anti-parasitic drugs, there are few definitive reports of resistance to PZQ in the literature.
The lack of knowledge about PZQ’s molecular mechanism(s) undermines our ability to predict
how resistance might arise and also hinder our attempts to develop alternative antischistosomal
drugs which exploit the same target(s). Some PZQ derivatives have been identified
which also kill or paralyse schistosomes in culture. However, none of these are in widespread
clinical use. There is a pressing need for fundamental research into the molecular mechanism(
s) of action of PZQ. Such research would enable new avenues for antischsistosomal
drug discovery.
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Affiliation(s)
- Charlotte M. Thomas
- School of Biological Sciences, Queen's University Belfast, Medical Biology Centre, 97 Lisburn Road, Belfast BT9 7BL, United Kingdom
| | - David J. Timson
- School of Biological Sciences, Queen's University Belfast, Medical Biology Centre, 97 Lisburn Road, Belfast BT9 7BL, United Kingdom
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Santos SS, de Araújo RV, Giarolla J, Seoud OE, Ferreira EI. Searching for drugs for Chagas disease, leishmaniasis and schistosomiasis: a review. Int J Antimicrob Agents 2020; 55:105906. [PMID: 31987883 DOI: 10.1016/j.ijantimicag.2020.105906] [Citation(s) in RCA: 33] [Impact Index Per Article: 8.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/07/2019] [Revised: 01/14/2020] [Accepted: 01/18/2020] [Indexed: 12/16/2022]
Abstract
Chagas disease, leishmaniasis and schistosomiasis are neglected diseases (NDs) and are a considerable global challenge. Despite the huge number of people infected, NDs do not create interest from pharmaceutical companies because the associated revenue is generally low. Most of the research on these diseases has been conducted in academic institutions. The chemotherapeutic armamentarium for NDs is scarce and inefficient and better drugs are needed. Researchers have found some promising potential drug candidates using medicinal chemistry and computational approaches. Most of these compounds are synthetic but some are from natural sources or are semi-synthetic. Drug repurposing or repositioning has also been greatly stimulated for NDs. This review considers some potential drug candidates and provides details of their design, discovery and activity.
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Affiliation(s)
- Soraya Silva Santos
- Laboratory of Design and Synthesis of Chemotherapeutics Potentially Active in Neglected Diseases (LAPEN), Department of Pharmacy, Faculty of Pharmaceutical Sciences, University of São Paulo-USP, Avenue Professor Lineu Prestes, 580-Building 13, São Paulo SP, 05508-900, Brazil
| | - Renan Vinicius de Araújo
- Laboratory of Design and Synthesis of Chemotherapeutics Potentially Active in Neglected Diseases (LAPEN), Department of Pharmacy, Faculty of Pharmaceutical Sciences, University of São Paulo-USP, Avenue Professor Lineu Prestes, 580-Building 13, São Paulo SP, 05508-900, Brazil
| | - Jeanine Giarolla
- Laboratory of Design and Synthesis of Chemotherapeutics Potentially Active in Neglected Diseases (LAPEN), Department of Pharmacy, Faculty of Pharmaceutical Sciences, University of São Paulo-USP, Avenue Professor Lineu Prestes, 580-Building 13, São Paulo SP, 05508-900, Brazil
| | - Omar El Seoud
- Laboratory of Design and Synthesis of Chemotherapeutics Potentially Active in Neglected Diseases (LAPEN), Department of Pharmacy, Faculty of Pharmaceutical Sciences, University of São Paulo-USP, Avenue Professor Lineu Prestes, 580-Building 13, São Paulo SP, 05508-900, Brazil
| | - Elizabeth Igne Ferreira
- Laboratory of Design and Synthesis of Chemotherapeutics Potentially Active in Neglected Diseases (LAPEN), Department of Pharmacy, Faculty of Pharmaceutical Sciences, University of São Paulo-USP, Avenue Professor Lineu Prestes, 580-Building 13, São Paulo SP, 05508-900, Brazil.
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Lopes MS, Suzuki BM, Pereira GADN, Probst AC, Ferreira RS, Oliveira JTD, Tecchio KB, Santos FVD, Caffrey CR, Oliveira RBD. Ortho-nitrobenzyl derivatives as potential anti-schistosomal agents. BRAZ J PHARM SCI 2018. [DOI: 10.1590/s2175-97902018000217376] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022] Open
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7
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Peng X, Xu X, Chen S, Tian Z, Liu L, Liu Q. Cu(I)-catalyzed one-pot reactions of isatins, indoles, and amines toward unsymmetrically substituted 2-carbonylarylureas. Tetrahedron 2018. [DOI: 10.1016/j.tet.2018.02.019] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/29/2022]
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Gouveia MJ, Brindley PJ, Gärtner F, Costa JMCD, Vale N. Drug Repurposing for Schistosomiasis: Combinations of Drugs or Biomolecules. Pharmaceuticals (Basel) 2018; 11:E15. [PMID: 29401734 PMCID: PMC5874711 DOI: 10.3390/ph11010015] [Citation(s) in RCA: 38] [Impact Index Per Article: 6.3] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/25/2017] [Revised: 01/19/2018] [Accepted: 01/31/2018] [Indexed: 12/17/2022] Open
Abstract
Schistosomiasis is a major neglected tropical disease. Control of schistosomiasis currently relies on a single drug, praziquantel, and despite its efficacy against the all schistosome species that parasitize humans, it displays some problematic drawbacks and alone is ineffective in counteracting adverse pathologies associated with infection. Moreover, due to the development of the potential emergence of PZQ-resistant strains, the search for additional or alternative antischistosomal drugs have become a public health priority. The current drug discovery for schistosomiasis has been slow and uninspiring. By contrast, repurposing of existing approved drugs may offer a safe, rapid and cost-effective alternative. Combined treatment with PZQ and other drugs with different mode of action, i.e., antimalarials, shows promise results. In addition, a combination of anthelminthic drugs with antioxidant might be advantageous for modulating oxidative processes associated with schistosomiasis. Herein, we review studies dealing with combination therapies that involve PZQ and other anthelminthic drugs and/or antioxidant agents in treatment of schistosomiasis. Whereas PZQ combined with antioxidant agents might or might not interfere with anthelminthic efficacy, combinations may nonetheless ameliorate tissue damage and infection-associated complications. In fact, alone or combine with other drugs, antioxidants might be a valuable adjuvant to reduce morbidity and mortality of schistosomiasis. Therefore, attempting new combinations of anthelmintic drugs with other biomolecules such as antioxidants provides new avenues for discovery of alternatives to PZQ.
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Affiliation(s)
- Maria João Gouveia
- UCBIO/REQUIMTE, Laboratory of Pharmacology, Department of Drug Sciences, Faculty of Pharmacy, University of Porto, Rua de Jorge Viterbo, 228, 4050-313 Porto, Portugal.
- Center for the Study of Animal Science, ICETA, University of Porto, Praça Gomes Teixeira, Apartado 55142, 4031-401 Porto, Portugal.
- Department of Molecular Pathology and Immunology, Institute of Biomedical Sciences Abel Salazar (ICBAS), University of Porto, Rua de Jorge Viterbo Ferreira 228, 4050-313 Porto, Portugal.
| | - Paul J Brindley
- Department of Microbiology, Immunology & Tropical Medicine, and Research Center for Neglected Diseases of Poverty, School of Medicine & Health Sciences, George Washington University, Washington, DC 20037, USA.
| | - Fátima Gärtner
- Department of Molecular Pathology and Immunology, Institute of Biomedical Sciences Abel Salazar (ICBAS), University of Porto, Rua de Jorge Viterbo Ferreira 228, 4050-313 Porto, Portugal.
- Institute of Molecular Pathology and Immunology of the University of Porto (IPATIMUP), Rua Júlio Amaral de Carvalho, 45, 4200-135 Porto, Portugal.
- Institute of Investigation and Innovation in Health (i3s), Rua Alfredo Allen, 4200-135 Porto, Portugal.
| | - José M Correia da Costa
- Center for the Study of Animal Science, ICETA, University of Porto, Praça Gomes Teixeira, Apartado 55142, 4031-401 Porto, Portugal.
- Department of Infectious Diseases, INSA-National Health Institute Dr. Ricardo Jorge, Rua Alexandre Herculano 321, 4000-055 Porto, Portugal.
| | - Nuno Vale
- UCBIO/REQUIMTE, Laboratory of Pharmacology, Department of Drug Sciences, Faculty of Pharmacy, University of Porto, Rua de Jorge Viterbo, 228, 4050-313 Porto, Portugal.
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Abstract
Praziquantel has remained the drug of choice for schistosomiasis chemotherapy for almost 40 years. The pressing need to develop a new antischistosomal drug may necessitate exploring and filtering chemotherapeutic history to search for the most promising ones. In this context, this review attempts to summarize all progress made in schistosomiasis chemotherapy from the early 20th century (mid-1910s) to 2016. We gathered almost 100 compounds providing information on therapeutic action, specifically covering at least first in vivo studies in animal model and in vitro. Pharmacokinetic and toxicity profiles of antischistosomal agents were also described. Preclinical studies indicate a handful of promising future candidates.
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da Silva VBR, Campos BRKL, de Oliveira JF, Decout JL, do Carmo Alves de Lima M. Medicinal chemistry of antischistosomal drugs: Praziquantel and oxamniquine. Bioorg Med Chem 2017; 25:3259-3277. [DOI: 10.1016/j.bmc.2017.04.031] [Citation(s) in RCA: 59] [Impact Index Per Article: 8.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/01/2017] [Revised: 04/21/2017] [Accepted: 04/26/2017] [Indexed: 12/20/2022]
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Jiang L, Peng X, Huang P, Chen Z, Liu L. TEMPO-catalyzed oxidative dimerization and cyanation of indoles for the synthesis of 2-(1H-indol-3-yl)-3-oxoindoline-2-carbonitriles. Tetrahedron 2017. [DOI: 10.1016/j.tet.2017.01.032] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/23/2022]
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Pretzel J, Mohring F, Rahlfs S, Becker K. Antiparasitic peptides. ADVANCES IN BIOCHEMICAL ENGINEERING/BIOTECHNOLOGY 2016; 135:157-92. [PMID: 23615879 DOI: 10.1007/10_2013_191] [Citation(s) in RCA: 20] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 02/20/2023]
Abstract
: The most important parasitic diseases, malaria, leishmaniasis, trypanosomiasis, and schistosomiasis, are a great burden to mankind, threatening the life of millions of people worldwide and mostly affecting the poorest. Because drug resistance is increasing and vaccines are rarely available, novel chemotherapeutic compounds are necessary in order to treat these devastating diseases. Insects serve as vectors of many human parasitic diseases and have been shown to express a huge variety of antimicrobial peptides (AMPs). Therefore, research activity on insect-derived AMPs has been increasing in the last 40 years. This chapter summarizes the current state of research on the possible role of AMPs as potential chemotherapeutic compounds against human parasitic diseases. As a representative antimicrobial peptide with antiparasitic activity, the structure of insect defensin A is shown [PDB accession code: 1ICA]. The molecule is surrounded by schematic representations of the human pathogenic parasites Plasmodium, Leishmania and Trypanosoma.
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Affiliation(s)
- Jette Pretzel
- Biochemistry and Molecular Biology, Interdisciplinary Research Center, Heinrich-Buff-Ring 26-32, 35392, Giessen, Germany
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Cheng PC, Lin CN, Peng SY, Kang TF, Lee KM. Combined IL-12 Plasmid and Recombinant SjGST Enhance the Protective and Anti-pathology Effect of SjGST DNA Vaccine Against Schistosoma japonicum. PLoS Negl Trop Dis 2016; 10:e0004459. [PMID: 26891172 PMCID: PMC4758724 DOI: 10.1371/journal.pntd.0004459] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/09/2015] [Accepted: 01/23/2016] [Indexed: 01/10/2023] Open
Abstract
Schistosomiasis is listed as one of most important tropical diseases and more than 200 million people are estimated to be infected. Development of a vaccine is thought to be the most effective way to control this disease. Recombinant 26-kDa glutathione S-transferase (rSjGST) has previously been reported to achieve a worm reduction rate of 42-44%. To improve the efficiency of the vaccine against Schistosoma japonicum, we immunized mice with a combination of pcDNA vector-encoded 26-kDa SjGST (pcDNA/SjGST), IL-12 expressing-plasmid (pIL-12), and rSjGST. Co-vaccination with pcDNA/SjGST, pIL-12, and rSjGST led to a reduction in worm burden, hepatic egg burden, and the size of liver tissue granulomas than that in the untreated infection controls. In addition, we detected high levels of specific IgG, IgG1, and IgG2a against the rSjGST antigen in infected mice vaccinated with this combination of pcDNA/SjGST, pIL-12, and rSjGST. Moreover, high expression levels of Th2 cytokines, including IL-4 and IL-10, were also detected in this group, without diminished levels of IL-12, INF-γ, and TNF-α cytokines that are related to parasite killing. In conclusion, we have developed a new vaccination regimen against S. japonicum infection and shown that co-immunization with pcDNA/SjGST vaccine, pIL-12, and rSjGST has significant anti-parasite, anti-hepatic egg and anti-pathology effects in mice. The efficacy of this vaccination method should be further validated in large animals such as water buffalo. This method may help to reduce the transmission of zoonotic schistosomiasis japonica.
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Affiliation(s)
- Po-Ching Cheng
- Department of Molecular Parasitology and Tropical Diseases, School of Medicine, Taipei Medical University, Taipei, Taiwan
- * E-mail: (PCC); (KML)
| | - Ching-Nan Lin
- Institute of Microbiology and Immunology, National Yang-Mng University, Taipei, Taiwan
- Institute of Tropical Medicine, National Yang-Mng University, Taipei, Taiwan
| | - Shih-Yi Peng
- Department of Biochemistry, College of Medicine, Tzu Chi University, Hualien, Taiwan
| | - Tsung-Fu Kang
- Institute of Tropical Medicine, National Yang-Mng University, Taipei, Taiwan
| | - Kin-Mu Lee
- Institute of Biotechnology, Central Taiwan University of Science and Technology, Taichung, Taiwan
- * E-mail: (PCC); (KML)
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Abstract
In recent years, natural product groups have been gaining prominence as possible sources of new drugs for schistosomiasis. This review attempts to update the antischistosomal natural compounds, or natural product-derived compounds, from the mid-1980s. Some of the main metabolites obtained from plants (e.g., terpenes, alkaloids, phenolic compounds and peptides) with in vitro and/or in vivo antischistosomal properties are discussed. Less thoroughly, due to scarcity of data in the literature, molecules from animals (e.g., peptides) are also described. Special mention of the anthelmintic activity against different parasitic stages of schistosomes is made; the mechanism of action of most of the metabolites is discussed, and a number of bioassay procedures are listed.
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Vimieiro ACS, Araújo N, Katz N, Kusel JR, Coelho PMZ. Schistogram changes after administration of antischistosomal drugs in mice at the early phase of Schistosoma mansoni infection. Mem Inst Oswaldo Cruz 2015; 108:881-6. [PMID: 24271044 PMCID: PMC3970651 DOI: 10.1590/0074-0276130135] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/17/2013] [Accepted: 06/12/2013] [Indexed: 01/22/2024] Open
Abstract
Mice infected with Schistosoma mansoni were treated with oxamniquine, praziquantel, artesunate at the pre-patent phase, aiming at observing schistogram alterations. Half of the animals were perfused five days post-treatment for counting and classification of immature worms, based on pre-established morphological criteria (schistogram); the remaining animals were evaluated 42 or 100 days after infection and perfusion of the portal-system was performed for collection and counting of adult worms and oogram. It was observed that oxamniquine and artesunate treatment administered at the pre-postural phase causes significant reduction in the number of immature and adult worms. However, there was little reduction with praziquantel when used at the dose of 400 mg/kg for treatments administered 14, 15, 21 or 23 days post-infection. Artesunate was responsible for significant alterations in development of young worms, as well as for a higher number of worms presenting intestinal damages. Immature adult worms were detected in mice treated with artesunate or oxamniquine at the pre-patent phase of infection and recovered by perfusion 100 days after infection. Schistogram proved to be a very useful tool for experimental evaluation of the activity of antischistosomal drugs and a good model to identify the most sensitive stages to drugs.
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Abstract
Schistosomiasis is a neglected tropical disease responsible for the death of more than 300,000 people every year. The disease is caused by intravascular parasitic platyhelminths called schistosomes. Treatment and control of schistosomiasis rely on a single drug, praziquantel, and concern exists over the possible emergence of resistance to this drug. The recent completion of the genome sequences of the three main worm species that cause schistosomiasis in humans has raised hope for the development of new interventions to treat the disease. RNA interference (RNAi), a mechanism by which gene-specific double-stranded RNA (dsRNA) triggers degradation of homologous mRNA transcripts, has emerged as an important tool to evaluate and validate new potential drug targets. In addition, RNAi has been used to explore the basic biology of these debilitating parasites. RNAi can be achieved in all stages of the parasite's life cycle in which it has been tested. In this review, we describe methods for applying RNAi to suppress gene expression in the intra-mammalian life stages (adults and schistosomula) of Schistosoma mansoni. We describe procedures for isolating and culturing the parasites, preparing and delivering dsRNA targeting a specific gene, as well as a procedure to evaluate gene suppression by quantitative real-time PCR.
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Issa I, Osman M, Aftimos G. Schistosomiasis manifesting as a colon polyp: a case report. J Med Case Rep 2014; 8:331. [PMID: 25296942 PMCID: PMC4196203 DOI: 10.1186/1752-1947-8-331] [Citation(s) in RCA: 18] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/22/2014] [Accepted: 08/19/2014] [Indexed: 12/14/2022] Open
Abstract
INTRODUCTION Schistosomiasis is a rare disease with a common intestinal involvement. However, colon polyps associated with Schistosoma in the absence of inflammation have rarely been reported, especially in young people; this is the first case with the following presentation. CASE PRESENTATION We describe the case of a 20-year-old Ethiopian woman living in Lebanon who presented with nonspecific abdominal symptoms. Her biochemical profile was normal in addition to the results of her stool and urine tests. A colonoscopy showed normal colonic mucosa but surprisingly a large pedunculated polyp was found in her ascending colon. Pathology revealed a hamartomatous polyp but it was full of partially calcified parasitic eggs of Schistosoma mansoni compatible with chronic schistosomiasis. CONCLUSIONS She was treated with two doses of praziquantel and showed immediate marked clinical improvement. This unusual case will give us the opportunity to discuss schistosomiasis, its occurrence in colon polyps, clinical significance and the various means of management.
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Affiliation(s)
- Iyad Issa
- Department of Gastroenterology and Hepatology, Rafic Hariri University Hospital (RHUH), Beirut, Lebanon.
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18
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Selim S, El Sagheer O, El Amir A, Barakat R, Hadley K, Bruins MJ, El Ridi R. Efficacy and safety of arachidonic acid for treatment of Schistosoma mansoni-infected children in Menoufiya, Egypt. Am J Trop Med Hyg 2014; 91:973-81. [PMID: 25246692 DOI: 10.4269/ajtmh.14-0328] [Citation(s) in RCA: 19] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/07/2022] Open
Abstract
Arachidonic acid (ARA), an omega-6 fatty acid, kills juvenile and adult schistosomes in vitro and displays highly significant and safe therapeutic effects in mice and hamsters infected with Schistosoma mansoni or S. haematobium. This study aims to examine the efficacy and safety of ARA in treatment of school-age children infected with S. mansoni. In total, 66 S. mansoni-infected schoolchildren (20-23 children/study arm) received a single dose of 40 mg/kg praziquantel (PZQ), ARA (10 mg/kg per day for 15 days), or PZQ combined with ARA. The children were examined before and after treatment for worm egg counts in stool and blood biochemical and immunological parameters. ARA proved to be as efficacious as PZQ in treatment of schoolchildren with low infection intensity (78% and 85% cure rates, respectively). For moderate-intensity infection, the ARA and PZQ combination led to 100% cure rate. Biochemical, hematological, and immunological parameters were either unchanged or ameliorated after ARA therapy.
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Affiliation(s)
- Sahar Selim
- Department of Parasitology, National Liver Institute, Menoufiya University, Shebin El-Kom, Menoufiya, Egypt; Zoology Department, Faculty of Science, Cairo University, Cairo, Egypt; Tropical Health Department, High Institute of Public Health, Alexandria University, Alexandria, Egypt; Human Evidence Department, DSM North America, Columbia, Maryland; Research and Development Department, DSM Biotechnology Center, Delft, The Netherlands
| | - Ola El Sagheer
- Department of Parasitology, National Liver Institute, Menoufiya University, Shebin El-Kom, Menoufiya, Egypt; Zoology Department, Faculty of Science, Cairo University, Cairo, Egypt; Tropical Health Department, High Institute of Public Health, Alexandria University, Alexandria, Egypt; Human Evidence Department, DSM North America, Columbia, Maryland; Research and Development Department, DSM Biotechnology Center, Delft, The Netherlands
| | - Azza El Amir
- Department of Parasitology, National Liver Institute, Menoufiya University, Shebin El-Kom, Menoufiya, Egypt; Zoology Department, Faculty of Science, Cairo University, Cairo, Egypt; Tropical Health Department, High Institute of Public Health, Alexandria University, Alexandria, Egypt; Human Evidence Department, DSM North America, Columbia, Maryland; Research and Development Department, DSM Biotechnology Center, Delft, The Netherlands
| | - Rashida Barakat
- Department of Parasitology, National Liver Institute, Menoufiya University, Shebin El-Kom, Menoufiya, Egypt; Zoology Department, Faculty of Science, Cairo University, Cairo, Egypt; Tropical Health Department, High Institute of Public Health, Alexandria University, Alexandria, Egypt; Human Evidence Department, DSM North America, Columbia, Maryland; Research and Development Department, DSM Biotechnology Center, Delft, The Netherlands
| | - Kevin Hadley
- Department of Parasitology, National Liver Institute, Menoufiya University, Shebin El-Kom, Menoufiya, Egypt; Zoology Department, Faculty of Science, Cairo University, Cairo, Egypt; Tropical Health Department, High Institute of Public Health, Alexandria University, Alexandria, Egypt; Human Evidence Department, DSM North America, Columbia, Maryland; Research and Development Department, DSM Biotechnology Center, Delft, The Netherlands
| | - Maaike J Bruins
- Department of Parasitology, National Liver Institute, Menoufiya University, Shebin El-Kom, Menoufiya, Egypt; Zoology Department, Faculty of Science, Cairo University, Cairo, Egypt; Tropical Health Department, High Institute of Public Health, Alexandria University, Alexandria, Egypt; Human Evidence Department, DSM North America, Columbia, Maryland; Research and Development Department, DSM Biotechnology Center, Delft, The Netherlands
| | - Rashika El Ridi
- Department of Parasitology, National Liver Institute, Menoufiya University, Shebin El-Kom, Menoufiya, Egypt; Zoology Department, Faculty of Science, Cairo University, Cairo, Egypt; Tropical Health Department, High Institute of Public Health, Alexandria University, Alexandria, Egypt; Human Evidence Department, DSM North America, Columbia, Maryland; Research and Development Department, DSM Biotechnology Center, Delft, The Netherlands
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19
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Taman A, Azab M. Present-day anthelmintics and perspectives on future new targets. Parasitol Res 2014; 113:2425-33. [PMID: 24894082 DOI: 10.1007/s00436-014-3969-7] [Citation(s) in RCA: 35] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/05/2014] [Accepted: 05/25/2014] [Indexed: 12/29/2022]
Abstract
In absence of vaccines for the majority of helminths, chemotherapy is still the mainstay for controlling human helminthiases. However, a limited number of drugs are available in the market to combat parasitic helminths in human. Besides, the development and spread of drug resistance have declined the use of most currently available anthelmintics. Clearly, availability of new anthelmintic agents will be essential in the next few years. More research into the mechanisms of drug actions and their targets are eminent for the discovery and development of novel anthelmintic agents. Recent drug discovery techniques mostly rely on mechanism-based screening of compounds on heterologously expressed targets in bacterial, mammalian or yeast cells. Although this is usually a successful approach, it is money- and time-consuming; meanwhile, pharmaceutical companies prefer the tested target that is chosen based on basic research. The nervous system is the site of action of several chemotherapeutics including pesticides and antinematode drugs; accordingly, the nervous system continues to be a promising target. Recent advances in exploring helminths' nervous system, neurotransmitters and receptors have paved the way for the development of potential agents targeting the nervous system and its components.
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Affiliation(s)
- Amira Taman
- Department of Medical Parasitology, Faculty of Medicine, Mansoura University, Mansoura, 35516, Egypt,
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20
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Chistyachenko YS, Khvostov MV, Belousov AI, Zhukova NA, Pakharukova MY, Katokhin AV, Khalikov SS, Tolstikova TG, Dushkin AV, Mordvinov VA, Lyakhov NZ. Physicochemical properties and anti-opisthorchosis effect of mechanochemically synthesized supramolecular complexes of Albendazole with the polysaccharide Arabinogalactan from Larix sibirica and Larix gmelinii. DOKLADY BIOLOGICAL SCIENCES : PROCEEDINGS OF THE ACADEMY OF SCIENCES OF THE USSR, BIOLOGICAL SCIENCES SECTIONS 2014; 456:212-214. [PMID: 24985519 DOI: 10.1134/s0012496614030156] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/29/2013] [Indexed: 06/03/2023]
Affiliation(s)
- Yu S Chistyachenko
- Institute of Solid State Chemistry and Mechanochemistry, Siberian Branch, Russian Academy of Sciences, Novosibirsk, Russia
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21
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22
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Lu J, Jiang S, Ye S, Deng Y, Ma S, Li CP. CpG oligodeoxynucleotide ligand potentiates the activity of the pVAX1-Sj26GST. Biomed Rep 2013; 1:609-613. [PMID: 24648995 DOI: 10.3892/br.2013.99] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/22/2013] [Accepted: 04/17/2013] [Indexed: 12/24/2022] Open
Abstract
Schistosomiasis is considered one of the most important neglected tropical diseases and remains a major public health problem in endemic countries. Toll-like receptor (TLR) ligands have been investigated as potential vaccine adjuvants for tumor and virus immunotherapy. However, few TLR ligands affecting schistosoma vaccines have been characterized. In this study, we evaluated a TLR9 ligand (CpG oligodeoxynucleotide 1826, CpG) as an adjuvant for a partially protective DNA vaccine encoding a 26-kDa glutathione S-transferase of Schistosoma japonicum (pVAX1-Sj26GST). Vaccination with pVAX1-Sj26GST in combination with CpG inhibited Treg immunosuppressive function, upregulated the production of interferon (IFN)-γ, tumor necrosis factor (TNF)-α, interleukin (IL)-4, IL-10, IL-2 and IL-6, and decreased CD4+CD8+Foxp3+ expression in vitro, which may contribute to the escape from Treg-mediated suppression during vaccination, allowing expansion of antigen-specific T cells against pathogens. In conclusion, our data demonstrated that selective TLR ligand combination may increase protective efficacy against schistosomiasis, which may synergistically antagonize Treg-mediated suppression.
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Affiliation(s)
- Jun Lu
- Department of Pathogen Biology and Immunology, School of Medicine, Anhui University of Science and Technology, P.R. China
| | - Shan Jiang
- Department of Mining Engineering, Huainan Vocational and Technical College, Huainan, Anhui 232001, P.R. China
| | - Song Ye
- Department of Pathogen Biology and Immunology, School of Medicine, Anhui University of Science and Technology, P.R. China
| | - Yun Deng
- Department of Pathogen Biology and Immunology, School of Medicine, Anhui University of Science and Technology, P.R. China
| | - Shuai Ma
- Department of Pathogen Biology and Immunology, School of Medicine, Anhui University of Science and Technology, P.R. China
| | - Chao-Pin Li
- Department of Pathogen Biology, Bengbu Medical College, Wuhu, Anhui 241002, P.R. China
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23
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Wang X, Dong L, Ni H, Zhou S, Xu Z, Hoellwarth JS, Chen X, Zhang R, Chen Q, Liu F, Wang J, Su C. Combined TLR7/8 and TLR9 ligands potentiate the activity of a Schistosoma japonicum DNA vaccine. PLoS Negl Trop Dis 2013; 7:e2164. [PMID: 23593527 PMCID: PMC3617091 DOI: 10.1371/journal.pntd.0002164] [Citation(s) in RCA: 23] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/25/2012] [Accepted: 03/01/2013] [Indexed: 01/07/2023] Open
Abstract
Background Toll-like receptor (TLR) ligands have been explored as vaccine adjuvants for tumor and virus immunotherapy, but few TLR ligands affecting schistosoma vaccines have been characterized. Previously, we developed a partially protective DNA vaccine encoding the 26-kDa glutathione S-transferase of Schistosoma japonicum (pVAX1-Sj26GST). Methodology/Principal Findings In this study, we evaluated a TLR7/8 ligand (R848) and a TLR9 ligand (CpG oligodeoxynucleotides, or CpG) as adjuvants for pVAX1-Sj26GST and assessed their effects on the immune system and protection against S. japonicum. We show that combining CpG and R848 with pVAX1-Sj26GST immunization significantly increases splenocyte proliferation and IgG and IgG2a levels, decreases CD4+CD25+Foxp3+ regulatory T cells (Treg) frequency in vivo, and enhances protection against S. japonicum. CpG and R848 inhibited Treg-mediated immunosuppression, upregulated the production of interferon (IFN)-γ, tumor necrosis factor (TNF)-α, interleukin (IL)-4, IL-10, IL-2, and IL-6, and decreased Foxp3 expression in vitro, which may contribute to prevent Treg suppression and conversion during vaccination and allow expansion of antigen-specific T cells against pathogens. Conclusions Our data shows that selective TLR ligands can increase the protective efficacy of DNA vaccines against schistosomiasis, potentially through combined antagonism of Treg-mediated immunosuppression and conversion. There is evidence that TLR activation can block Treg cell responses and thereby break tolerance to self-antigens. It is expected that the use of TLR ligands as vaccine adjuvants will induce potent anti-pathogen immune responses and simultaneously overcome immune inhibition mediated by Tregs. However, the impact of TLR ligands on schistosomiasis vaccines is unclear. Here, we demonstrate that the use of a TLR7/8 ligand (R848) and a TLR9 ligand (CpG) as adjuvants in combination with the S. japonicum vaccine pVAX1-Sj26GST improves disease protection. The combination of CpG and R848 administered after vaccination causes an immune response marked by an upregulation of splenocyte proliferation and IgG and IgG2a levels that also coincides with a decreased proportion of CD4+CD25+ Tregs in mice. We also show that combined adjuvant use of CpG and R848 may impair Treg development and function by promoting the secretion of proinflammatory cytokines and reducing Foxp3 expression. Our findings suggest that in combination with the vaccine, TLR ligands may protect the effector response from Treg-mediated suppression, thereby eliciting the appropriate immune response to improve vaccine efficacy. Immunization combined with the TLR ligands CpG and R848 thus represents a promising new approach for the design of schistosoma vaccines.
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Affiliation(s)
- Xuefeng Wang
- Department of Central Laboratory, The Affiliated People's Hospital, Jiangsu University, Zhenjiang, Jiangsu, People's Republic of China.
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24
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El-Beshbishi SN, Taman A, El-Malky M, Azab MS, El-Hawary AK, El-Tantawy DA. First insight into the effect of single oral dose therapy with artemisinin-naphthoquine phosphate combination in a mouse model of Schistosoma mansoni infection. Int J Parasitol 2013; 43:521-30. [PMID: 23500074 DOI: 10.1016/j.ijpara.2013.01.007] [Citation(s) in RCA: 20] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/09/2012] [Revised: 01/10/2013] [Accepted: 01/11/2013] [Indexed: 12/21/2022]
Abstract
Praziquantel is the current drug of choice against schistosomiasis. The dependency on praziquantel exclusively is problematic, given the spread of the disease and the threat of drug resistance. This study investigates an alternative antischistosomal drug using the compound naphthoquine phosphate tablet, which is a novel single oral dose antimalarial drug, containing a combination of naphthoquine phosphate and artemisinin. In the present study, the therapeutic efficacies of different artemisinin-naphthoquine phosphate combination-dosing protocols were evaluated in experimentally infected mice harbouring juvenile or adult stages of Schistosoma mansoni (Egyptian strain). The study shows that the oral administration of artemisinin-naphthoquine phosphate combination in a single dose of 400 mg/kg on day 7 p.i. resulted in a significant worm burden reduction of 95.07%. When used at a dose of 600 mg/kg on day 21 p.i., all female worms were killed before depositing eggs, resulting in complete absence of eggs in hepatic and intestinal tissues. The same dose given on day 42 p.i. reduced total and female worm burdens by 93.36% and 94.17%, respectively. In addition, artemisinin-naphthoquine phosphate combination induced significant reductions of 80.18% and 76.73% in the hepatic and intestinal tissue egg loads, respectively. Artemisinin-naphthoquine phosphate combination also induced significant alterations in the oogram pattern with elevated levels of dead eggs. Antipathological activities were evident in the amelioration of hepatic granulomata. Our findings hold promise for the development of a novel antischistosomal drug using an artemisinin-naphthoquine phosphate combination. Further in vitro and in vivo studies should be launched to elucidate the possible mechanism/s of action and to study the effect of artemisinin-naphthoquine phosphate combination on other human schistosomes.
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Affiliation(s)
- Samar N El-Beshbishi
- Department of Medical Parasitology, Faculty of Medicine, Mansoura University, Mansoura 35516, Egypt.
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25
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Lochmatter C, Schneider CL, Ingram K, Keiser J, Schifferli JA. Schistosoma mansoni tetraspanning orphan receptor (SmTOR): a new vaccine candidate against schistosomiasis. Clin Exp Immunol 2013; 170:342-57. [PMID: 23121675 DOI: 10.1111/j.1365-2249.2012.04667.x] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/11/2022] Open
Abstract
One approach to fight against schistosomiasis is to develop an efficient vaccine. Schistosoma mansoni tetraspanning orphan receptor (SmTOR) might be a vaccine candidate, as it is a tegument membrane protein expressed most highly in cercariae. In this study we characterized the recombinant first extracellular domain of SmTOR (rSmTORed1) as having the expected property to bind C2 of complement similarly to a smaller peptide of the same domain, and to produce specific and high-titre antibodies in BALB/c mice immunized using complete Freund's adjuvant/incomplete Freund's adjuvant (CFA/IFA). Immunization was protective against parasite infection, as demonstrated by a significant decrease in worm burden in immunized BALB/c mice versus the control groups over two independent trials [64 and 45% reduction for mean adult worm burden in immunized versus phosphate-bufferd saline (PBS) injected mice]. Interestingly, infection by itself did not lead to the generation of anti-rSmTORed1 antibodies, corresponding to the low frequency of specific anti-rSmTORed1 antibodies detected in the sera of patients infected with S. mansoni (2/20; 10%). These data suggest that, as opposed to the natural infection during which SmTOR induces antibodies only rarely, immunization with its smaller first extracellular domain might be more efficient.
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Affiliation(s)
- C Lochmatter
- Immunonephrology Laboratory, Department of Biomedicine, University Hospital Basel, Basel, Switzerland.
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26
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Pereira ASA, Cavalcanti NL, Nascimento GAF, Nascimento-Silva JLG, Padilha RJR, Viegas LFW, Alves LC, Lima-Filho JL, Chaves MEC. Morphological and morphometric study of cercariae and adult worms of Schistosoma mansoni (SLM strain) isolated from infected mice. Parasitol Res 2012; 112:1087-96. [PMID: 23263251 DOI: 10.1007/s00436-012-3235-9] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/15/2012] [Accepted: 11/30/2012] [Indexed: 11/28/2022]
Abstract
In northeastern Brazil, the schistosomiasis is historically endemic and considered as a public health problem. The Schistosoma mansoni São Lourenço da Mata (SLM-PE, Brazil) strain was used in several paper already published; however, morphological and morphometric studies about this strain was never done. In this work, scanning electron microscopy (SEM) was used in morphological and morphometric analysis of cercariae and adult worms. Cercariae were obtained from Biomphalaria glabrata snails and adult worms from mice, both infected by the S. mansoni SLM strain, fixed and prepared for SEM. The results showed that cercariae of S. mansoni measures 254.9 μm of length. The bodies are covered by spines, with a ventral sucker, an oral sucker with sensory receivers, and a pair of penetration glands in the head. The area of tail and body and the distance between suckers were 3,011.77, 1,530.32, and 42.9 μm, respectively. Adult worms of S. mansoni were divided into three main regions: the anterior, medial, and posterior, besides the gynecophoral canal in males. The measure of adult worms of S. mansoni was 4 mm males and 5 mm females. The anterior region length of the male was 470 μm and of the female 271 μm. All the parameters were assayed in ten samples. The morphometric values found in the SLM strain were smaller than other S. mansoni strains described in the literature as well as other helminths. This is the first morphological and morphometric study with the SLM strain of S. mansoni being extremely important for improving control strategies and life quality of the local population.
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Affiliation(s)
- A S A Pereira
- Laboratório de Imunopatologia Keizo Asami (LIKA), Universidade Federal de Pernambuco, Avenida Professor Moraes Rego, s/n, CEP 50670-901, Recife, PE, Brazil
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27
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Effect of Mirazid in Schistosoma japonicum-infected mice: parasitological and pathological assessment. Parasitol Res 2012; 112:373-7. [DOI: 10.1007/s00436-012-3145-x] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/23/2012] [Accepted: 09/20/2012] [Indexed: 12/31/2022]
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Late splenosis evaluation after autoimplantation of spleen morsels in major omentum in hepatosplenic schistosomiasis patients using SPECT/CT imaging. Clin Nucl Med 2012; 37:372-3. [PMID: 22391708 DOI: 10.1097/rlu.0b013e31823ea497] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/26/2022]
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Wang X, Liu F, Zhou S, Xu Z, Hoellwarth J, Chen X, He L, Zhang R, Liu F, Wang J, Su C. Partial regulatory T cell depletion prior to schistosomiasis vaccination does not enhance the protection. PLoS One 2012; 7:e40359. [PMID: 22802961 PMCID: PMC3389001 DOI: 10.1371/journal.pone.0040359] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/15/2012] [Accepted: 06/07/2012] [Indexed: 11/21/2022] Open
Abstract
CD4+CD25+ regulatory T cells (Tregs) do
not only influence self-antigen specific immune responses, but also dampen
the protective effect induced by a number of vaccines. The impact of CD4+CD25+
Tregs on vaccines against schistosomiasis, a neglected tropical disease that
is a major public health concern, however, has not been examined. In this
study, a DNA vaccine encoding a 26 kDa glutathione S-transferase of Schistosoma
japonicum (pVAX1-Sj26GST) was constructed and its potential effects
were evaluated by depleting CD25+ cells prior to pVAX1-Sj26GST
immunization. This work shows that removal of CD25+ cells
prior to immunization with the pVAX1-Sj26GST schistosomiasis DNA vaccine significantly
increases the proliferation of splenocytes and IgG levels. However, CD25+
cell-depleted mice immunized with pVAX1-Sj26GST show no improved protection
against S. japonicum. Furthermore, depletion of CD25+
cells causes an increase in both pro-inflammatory cytokines (e.g. IFN-γ,
GM-CSF and IL-4) and an anti-inflammatory cytokine (e.g. IL-10), with CD4+CD25-
T cells being one of the major sources of both IFN-γ and IL-10. These
findings indicate that partial CD25+ cell depletion fails
to enhance the effectiveness of the schistosome vaccine, possibly due to IL-10
production by CD4+CD25- T cells, or other cell
types, after CD25+ cell depletion during vaccination.
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Affiliation(s)
- Xuefeng Wang
- Department of Pathogen Biology and Immunology, School of Medicine, Anhui University of Science and Technology, Huainan, Anhui, China.
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Lei L, Cheng L, Hou J, Guo S, Zhu C, Shi Y, Jiang Y, Lin J. Prevention of Schistosoma japonicum infection in mice with long-acting praziquantel implants. Exp Parasitol 2012; 131:442-7. [PMID: 22705923 DOI: 10.1016/j.exppara.2012.05.016] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/11/2012] [Revised: 05/31/2012] [Accepted: 05/31/2012] [Indexed: 11/29/2022]
Abstract
This work reports the prevention outcomes of a praziquantel (PZQ) implant against the infection of Schistosoma japonicum in mice. The PZQ implant produced stable plasma PZQ concentrations in a range of 100-1300 ng/mL for a period of 70 days, by releasing PZQ in subcutaneous tissues in a sustained manner. To assess the prevention effects, the mice were infected at varying times after implantation. All the mice were sacrificed at 6 weeks after infection for worm and egg recovery and counting, worm morphological examination, determination of egg-hatching rates, and analysis of hepatic histology. The infection was successfully prevented for mice with early infection times (within 2-3 weeks), as nearly no worms, paired worms, eggs, or miracidia were recovered. However, in mice with late infection times (after 3 weeks), the prevention effects were diminished due to the decreased plasma PZQ concentrations at late times. Interestingly, the implants showed robust prevention effects on repeated infection at 1 and 3 weeks. In the infection-prevented mouse livers, no granuloma formation or granulomatous inflammation was observed. The results demonstrated that by blocking the development of infecting miracidia and by deactivating the eggs, the PZQ implants encouragingly prevented the S. japonicum infection and avoided liver damage.
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Affiliation(s)
- Lei Lei
- School of Pharmacy, Shanghai Jiao Tong University, Shanghai 200240, China
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Xiao SH, Xue J, Mei JY, Jiao PY. Effectiveness of synthetic trioxolane OZ78 against Schistosoma japonicum in mice and rabbits. Parasitol Res 2011; 110:2307-14. [PMID: 22200956 DOI: 10.1007/s00436-011-2765-x] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/24/2011] [Accepted: 12/05/2011] [Indexed: 12/23/2022]
Abstract
Antischistosomal activities of a synthetic peroxide OZ78 (an ozonide carboxylic acid) against Schistosoma japonicum have been studied in mice and rabbits. Among 132 mice used, 30 of them were infected with 80-100 S. japonicum cercariae for collection of juvenile and adult schistosomes applied in in vitro tests. The remaining 102 mice were infected with 40 schistosome cercariae used for experimental treatment. Other 13 rabbits infected each with 200 schistosome cercariae were treated orally with OZ78 42 days post-infection. Most treated mice and rabbits were sacrificed 4 weeks post-treatment to collect residual schistosomes for evaluation of the drug efficacy. OZ78 and its sodium salt (OZ78-Na salt) 10-60 μg/mL alone exhibited no in vitro effect against day 14, day 21 schistosomula, and day 35 adult schistosomes. But OZ78 and OZ78-Na salt 10 and 20 μg/mL together with hemin 80 μg/mL showed decrease in worm motor activity and severe damage to the worm tegument and intestine, and all worms died within 3 days post-incubation. After infected mice were treated orally with OZ78 at a single dose of 400 mg/kg for 1 day, 34.9% of the worms shifted to the liver. Three and 7 days post-treatment, 100% of the worms were recovered from the liver. Fourteen days post-treatment, 92.3% of the worms still remained in the liver and 7.7% of the worms returned back to the mesenteric veins. Male and female worms shifted to the liver revealed in apparent shrinkage, degeneration of worm body, depigmentation in gut, and disappearance of ova in the uterus of some female worms. Meanwhile, dead worm and dead worm fragments were found in the liver tissues. In mice infected with various stages of schistosomes and treated orally with single OZ78 400 mg/kg, moderate or potential effect of the drug against day 0 (3-h-old worm), day 7, day 14, and day 21 juvenile worms and day 28, day 35 as well as day 42 adult worms were observed, the differences of total or female worm burdens between each treated group and control group were statistically significant (P < 0.01 or P < 0.05). Among the various stages of juveniles, day 7 worms were more susceptible to OZ78 with worm reduction of 83.8%, while the effect of OZ78 against day 28 to day 42 adult worms were similar. Finally, rabbits infected with adult schistosomes and treated with OZ78 at a single dose of 45 mg/kg or a daily dose of 35 mg/kg for three consecutive days resulted in significantly lower total and female worm burdens in comparison with that of control (P < 0.05) with total and female worm reductions of 84.1% and 84.7% as well as 74.3% and 77.4%, respectively. The results demonstrate that OZ78 possesses effect against both juvenile and adult S. japonicum in mouse model, and also shows effect against adult schistosomes in rabbits.
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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, People's Republic of China.
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Cheng L, Lei L, Guo S, Zhu C, Rong H, Guo D, Zhang L, Jiang Y, Lin J. Schistosoma japonicum: Treatment of different developmental stages in mice with long-acting praziquantel implants. Exp Parasitol 2011; 129:254-9. [DOI: 10.1016/j.exppara.2011.08.003] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/13/2011] [Revised: 08/03/2011] [Accepted: 08/03/2011] [Indexed: 11/26/2022]
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In vitro efficacy of the essential oil of Piper cubeba L. (Piperaceae) against Schistosoma mansoni. Parasitol Res 2011; 110:1747-54. [PMID: 22006194 DOI: 10.1007/s00436-011-2695-7] [Citation(s) in RCA: 26] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/26/2011] [Accepted: 10/07/2011] [Indexed: 12/16/2022]
Abstract
In this paper, cercariae, schistosomula, and adult Schistosoma mansoni worms were incubated in vitro with the essential oil of Piper cubeba (PC-EO) at concentrations from 12.5 to 200 μg/mL, and the viability was evaluated using an inverted microscopy. The effects of PC-EO at 100 and 200 μg/mL on the stages of S. mansoni were similar to those of the positive control (PZQ at 12.5 μg/mL), with total absence of mobility after 120 h. However, at concentrations from 12.5 to 50 μg/mL, PC-EO caused a reduction in the viability of cercariae and schistosomula when compared with the negative control groups (RPMI 1640 or dechlorinated water) or (RPMI 1640 + 0.1% DMSO or dechlorinated water + 0.1% DMSO). On the other hand, adult S. mansoni worms remained normally active when incubated with PC-EO at concentrations of 12.5 and 25 μg/mL, and their viabilities were similar to those of the negative control groups. In addition, at concentrations ranging from 50 to 200 μg/mL, separation of all the coupled adult worms was observed after 24 h of incubation, which is related to the fact of the reduction in egg production at this concentration. The main chemical constituents of PC-EO were identified by gas chromatography-mass spectrometry as being sabinene (19.99%), eucalyptol (11.87%), 4-terpineol (6.36%), β-pinene (5.81%), camphor (5.61%), and δ-3-carene (5.34%). The cytotoxicity of the PC-EO was determined, and a significant cytotoxicity was only obtained in the concentration of 200 μg/mL after 24 h treatment. The results suggest that PC-EO possesses an effect against cercariae, schistosomula, and adult worms of the S. mansoni.
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Pereira ASA, Padilha RJR, Lima-Filho JL, Chaves MEC. Scanning electron microscopy of the human low-density lipoprotein interaction with the tegument of Schistosoma mansoni. Parasitol Res 2011; 109:1395-402. [PMID: 21503638 DOI: 10.1007/s00436-011-2386-4] [Citation(s) in RCA: 17] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/16/2011] [Accepted: 04/06/2011] [Indexed: 12/15/2022]
Abstract
The interaction between host molecules and Schistosoma mansoni has been regarded as a key feature for parasite survival. In this work, scanning electron microscopy was used to study the interaction of human low-density lipoprotein (LDL) with the tegument of the adult worm of S. mansoni. Worms were incubated in RPMI 1640 containing 10% of LPDS and 40 μg LDL/mL during 30, 60, and 120 min. Control worms were processed in the same way, without LDL. After the incubations, the samples were fixed and processed to scanning electron microscopy. The results demonstrated interaction of the LDL particles with the male parasite tegument. Male and female worms incubated without LDL from 0 (control) to 120 min did not show alterations in the tegument. It was observed a larger number of LDL particles on the dorsal region of male adult worm than others regions (anterior, posterior and gynecophoral canal). The female tegument did not show adherence of LDL. Aggregates on the tegument of the male worm were in greater number and size in the incubation times of 30 and 60 min than 120 min. The comparison between 30 and 120 min of incubation showed that the particles' size diminished from 2,650-860 nm to 634-363 nm, respectively. Such reduction can be due to the capture and the use of the lipids by the worm. Therefore, the internalization of lipids from LDL by the male worms seems to be a mechanism independent of endocytosis. Differences between males and females suggest lipid transference from male to female through gynecophoral canal.
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Affiliation(s)
- Adriana S A Pereira
- Laboratório de Imunopatologia Prof. Keizo Asami (LIKA), Universidade Federal de Pernambuco, Avenida Professor Moraes Rego, s/n-CEP 50670-901, Recife, Pernambuco, Brazil
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Li H, Gu C, Ren Y, Dai Y, Zhu X, Xu J, Li Y, Qiu Z, Zhu J, Zhu Y, Guan X, Feng Z. The efficacy of NP11-4-derived immunotoxin scFv-artesunate in reducing hepatic fibrosis induced by Schistosoma japonicum in mice. J Biomed Res 2011; 25:148-54. [PMID: 23554683 PMCID: PMC3596707 DOI: 10.1016/s1674-8301(11)60019-5] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/10/2010] [Revised: 12/14/2010] [Accepted: 01/09/2011] [Indexed: 11/23/2022] Open
Abstract
Schistosomiasis is one of the most prevalent parasitic diseases in China, and hepatic fibrosis caused by schistosome infection is the principal cause of death. The aim of this study was to evaluate the efficacy of NP11-4-derived immunotoxin scFv-artesunate on Schistosoma japonicum-induced hepatic fibrosis. A single-chain variable fragment (scFv) was generated from the murine anti-Schistosoma japonicum (S. japanicum) monoclonal antibody NP11-4. The scFv was expressed as a soluble protein and purified by Ni-affinity chromatography. After conjugation with artesunate, the binding ability with soluble egg antigens (SEA) was determined by an enzyme-linked immunosorbent assay (ELISA). The biological activity of purified scFv, scFv-artesunate (immunotoxin), and artesunate was detected in vivo. Image-Pro Plus software was used to analyze the size of egg granuloma and the extent of liver fibrosis. The recombinant scFv expession vector was constructed and expressed successfully. After purification by a His-trap Ni-affinity column, the scFv yield was approximately 0.8 mg/L of culture medium. ELISA results showed that chemical conjugation did not affect the binding activity of the immunotoxin. Our animal experiments indicated that the immunotoxin could significantly reduce the size of egg granuloma in the liver and inhibit hepatic fibrosis. The immunotoxin could be used as a promising candidate in the targeted therapy of S. japonicum-induced hepatic fibrosis.
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Affiliation(s)
- Hong Li
- Key Labortary of Antibody Technique of Ministry of Health, Nanjing Medical University, Nanjing, Jiangsu 210029, China
- Pathology Department, Nanjing Medical University, Nanjing, Jiangsu 210029, China
| | - Chunyan Gu
- Key Labortary of Antibody Technique of Ministry of Health, Nanjing Medical University, Nanjing, Jiangsu 210029, China
- Pathology Department, Nanjing Medical University, Nanjing, Jiangsu 210029, China
| | - Yongya Ren
- Key Labortary of Antibody Technique of Ministry of Health, Nanjing Medical University, Nanjing, Jiangsu 210029, China
- Pathology Department, Nanjing Medical University, Nanjing, Jiangsu 210029, China
| | - Yang Dai
- Jiangsu Institute of Parasitic Diseases, Wuxi, Jiangsu 214000, China
| | - Xiaojuan Zhu
- Key Labortary of Antibody Technique of Ministry of Health, Nanjing Medical University, Nanjing, Jiangsu 210029, China
- Pathology Department, Nanjing Medical University, Nanjing, Jiangsu 210029, China
| | - Jing Xu
- Key Labortary of Antibody Technique of Ministry of Health, Nanjing Medical University, Nanjing, Jiangsu 210029, China
| | - Yuhua Li
- Pathology Department, Nanjing Medical University, Nanjing, Jiangsu 210029, China
| | - Zhenning Qiu
- Key Labortary of Antibody Technique of Ministry of Health, Nanjing Medical University, Nanjing, Jiangsu 210029, China
| | - Jin Zhu
- Key Labortary of Antibody Technique of Ministry of Health, Nanjing Medical University, Nanjing, Jiangsu 210029, China
- Huadong Medical Institute of Biotechniques, Nanjing, Jiangsu 210002, China
| | - Yinchang Zhu
- Jiangsu Institute of Parasitic Diseases, Wuxi, Jiangsu 214000, China
| | - Xiaohong Guan
- Key Labortary of Antibody Technique of Ministry of Health, Nanjing Medical University, Nanjing, Jiangsu 210029, China
| | - Zhenqing Feng
- Key Labortary of Antibody Technique of Ministry of Health, Nanjing Medical University, Nanjing, Jiangsu 210029, China
- Pathology Department, Nanjing Medical University, Nanjing, Jiangsu 210029, China
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Abdul-Ghani R, Loutfy N, Sheta M, Hassan A. Artemether shows promising female schistosomicidal and ovicidal effects on the Egyptian strain of Schistosoma mansoni after maturity of infection. Parasitol Res 2010; 108:1199-205. [PMID: 21107863 DOI: 10.1007/s00436-010-2163-9] [Citation(s) in RCA: 25] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/13/2010] [Accepted: 11/10/2010] [Indexed: 11/26/2022]
Abstract
Artemether is an artemisinin derivative that is used as an antimalarial drug, especially in situations where chloroquine resistance is suspected. This compound has proved to be a good prophylactic agent against schistosomiasis japonica in China. In the present study, the therapeutic efficacies of different artemether-dosing protocols were evaluated in experimentally infected mice harbouring adult Schistosoma mansoni (Egyptian strain). Mice were treated on day 46 onwards with three dosing protocols (400 mg/kg/day for 2 days; 200 mg/kg/day for 4 days; 100 mg/kg/day for 6 days) after being infected. A number of parasitological and histopathological criteria were employed in the assessment of drug efficacies compared to infected untreated control 2 weeks post-treatment. The results of the present study suggest that artemether is efficacious against the Egyptian strain of S. mansoni with total worm reductions ranging from 40.7% to 59.7% and female worm reductions ranging from 69.3% to >90%. In addition, artemether induced significant reductions, ranging from 75.2% to 82.6%, in the liver tissue egg loads as well as significant reductions, ranging from 68.8% to 78.9% in the intestinal wall egg loads. It also induced significant alterations in the oogram pattern in the intestinal mucosa of infected mice with cessation of oviposition and increased rates of dead eggs. Antipathologic activities were also evident in the amelioration of granulomas in the liver with increased ratios of healed to active ones. In conclusion, artemether could be a promising agent in the control of schistosomiasis mansoni due to its schistosomicidal effects on female worms and to its ovicidal power as well as its potentiality in the improvement of hepatic lesions.
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Affiliation(s)
- Rashad Abdul-Ghani
- Department of Medical Parasitology, Faculty of Medicine and Health Sciences, Sana'a University, Sana'a, Yemen.
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Smout MJ, Kotze AC, McCarthy JS, Loukas A. A novel high throughput assay for anthelmintic drug screening and resistance diagnosis by real-time monitoring of parasite motility. PLoS Negl Trop Dis 2010; 4:e885. [PMID: 21103363 PMCID: PMC2982823 DOI: 10.1371/journal.pntd.0000885] [Citation(s) in RCA: 108] [Impact Index Per Article: 7.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/30/2010] [Accepted: 10/18/2010] [Indexed: 11/20/2022] Open
Abstract
Background Helminth parasites cause untold morbidity and mortality to billions of people and livestock. Anthelmintic drugs are available but resistance is a problem in livestock parasites, and is a looming threat for human helminths. Testing the efficacy of available anthelmintic drugs and development of new drugs is hindered by the lack of objective high-throughput screening methods. Currently, drug effect is assessed by observing motility or development of parasites using laborious, subjective, low-throughput methods. Methodology/Principal Findings Here we describe a novel application for a real-time cell monitoring device (xCELLigence) that can simply and objectively assess anthelmintic effects by measuring parasite motility in real time in a fully automated high-throughput fashion. We quantitatively assessed motility and determined real time IC50 values of different anthelmintic drugs against several developmental stages of major helminth pathogens of humans and livestock, including larval Haemonchus contortus and Strongyloides ratti, and adult hookworms and blood flukes. The assay enabled quantification of the onset of egg hatching in real time, and the impact of drugs on hatch rate, as well as discriminating between the effects of drugs on motility of drug-susceptible and –resistant isolates of H. contortus. Conclusions/Significance Our findings indicate that this technique will be suitable for discovery and development of new anthelmintic drugs as well as for detection of phenotypic resistance to existing drugs for the majority of helminths and other pathogens where motility is a measure of pathogen viability. The method is also amenable to use for other purposes where motility is assessed, such as gene silencing or antibody-mediated killing. Parasitic worms cause untold morbidity and mortality on billions of people and livestock. Drugs are available but resistance is problematic in livestock parasites and is a looming threat for human helminths. Currently, new drug discovery and resistance monitoring is hindered as drug efficacy is assessed by observing motility or development of parasites using laborious, subjective, low-throughput methods evaluated by eye using microscopy. Here we describe a novel application for a cell monitoring device (xCELLigence) that can simply and objectively assess real time anti-parasite efficacy of drugs on eggs, larvae and adults in a fully automated, label-free, high-throughput fashion. This technique overcomes the current low-throughput bottleneck in anthelmintic drug development and resistance detection pipelines. The widespread use of this device to screen for new therapeutics or emerging drug resistance will be an invaluable asset in the fight against human, animal and plant parasitic helminths and other pathogens that plague our planet.
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Affiliation(s)
| | | | | | - Alex Loukas
- James Cook University, Cairns, Australia
- * E-mail:
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