1
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Amador LA, Colón-Lorenzo EE, Rodríguez AD, Serrano AE. Probing the Antiplasmodial Properties of Plakortinic Acids C and D: An Uncommon Pair of Marine Peroxide-Polyketides Isolated from a Two-Sponge Association of Plakortis symbiotica and Xetospongia deweerdtae Collected near Puerto Rico. Life (Basel) 2024; 14:684. [PMID: 38929667 PMCID: PMC11204963 DOI: 10.3390/life14060684] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/12/2024] [Revised: 05/21/2024] [Accepted: 05/23/2024] [Indexed: 06/28/2024] Open
Abstract
Plakortinic acids C (1) and D (2), an unseparable pair of endoperoxide polyketides isolated and purified from the symbiotic association of Caribbean Sea sponges Plakortis symbiotica-Xestospongia deweerdtae, underwent in vitro evaluation for antiplasmodial activity against the malaria parasite Plasmodium berghei using a drug luminescence assay. Initial screening at 10 µM revealed 50% in vitro parasite growth inhibition. The title compounds displayed antiplasmodial activity with an EC50 of 5.3 µM toward P. berghei parasites. The lytic activity against erythrocytes was assessed through an erythrocyte cell lysis assay, which showed non-lytic activity at lower concentrations ranging from 1.95 to 3.91 µM. The antiplasmodial activity and the absence of hemolytic activity support the potential of plakortinic acids C (1) and D (2) as promising lead compounds. Moreover, drug-likeness (ADMET) properties assessed through the pkCSM server predicted high intestinal absorption, hepatic metabolism, and volume of distribution, indicating favorable pharmacokinetic profiles for oral administration. These findings suggest the potential suitability of these metabolites for further investigations of antiplasmodial activity in multiple parasitic stages in the mosquito and Plasmodium falciparum. Notably, this study represents the first report of a marine natural product exhibiting the unique 7,8-dioxatricyclo[4.2.2.02,5]dec-9-ene motif being evaluated against malaria.
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Affiliation(s)
- Luis A. Amador
- Molecular Sciences Research Center, University of Puerto Rico, 1390 Ponce de León Avenue, San Juan 00926, Puerto Rico;
| | - Emilee E. Colón-Lorenzo
- Department of Microbiology and Medical Zoology, University of Puerto Rico School of Medicine, San Juan 00921, Puerto Rico;
| | - Abimael D. Rodríguez
- Molecular Sciences Research Center, University of Puerto Rico, 1390 Ponce de León Avenue, San Juan 00926, Puerto Rico;
| | - Adelfa E. Serrano
- Department of Microbiology and Medical Zoology, University of Puerto Rico School of Medicine, San Juan 00921, Puerto Rico;
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2
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Proteomic analysis of Plasmodium berghei in the ring phase during in vivo antiparasitic treatment with kramecyne. Exp Parasitol 2022; 238:108262. [PMID: 35561785 DOI: 10.1016/j.exppara.2022.108262] [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: 05/20/2021] [Revised: 03/15/2022] [Accepted: 04/18/2022] [Indexed: 11/20/2022]
Abstract
Malaria is a parasitic disease of global importance due to its high annual death toll. The treatment for this infection is difficult for the increase in the populations of parasites resistant to the existing medicines, the development of new antimalarials is urgent needed. Several products developed for the control of malaria from herbalist have had a profound impact, for example, quinine obtained from the bark of the cinchona tree and recently those derived from artemisinin, whose discovery was the reason for the awarding of the 2015 Nobel Prize. The aim of the present study was to evaluate a compound named kramecyne extracted of "chayotillo" (Krameria cystisoides) plant used by the antiparasitic effect against some blood and intestinal protozoa (Giardia duodenalis y Trypanosoma cruzi). In addition is using for the treatment of inflammatory diseases. Measuring parasitaemia at different times, it was observed that in mice treated with kramecyne, it reached only 14% of parasitaemia at 7 days with a dose of 15 mg/kg, using chloroquine as a control drug, because it has not been demonstrated that parasites that infect rodents have developed resistance against this drug. Our results showed that kramecyne decreases the expression of parasite proteins that participate in biological processes, such as invasion, cytoadherence, pathogenicity and energy metabolism. With these results, it is proposed that this compound has repercussions on the metabolism of the parasite and could be useful for use as an antimalarial.
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3
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Joseph Sahayarayan J, Soundar Rajan K, Nachiappan M, Prabhu D, Guru Raj Rao R, Jeyakanthan J, Hossam Mahmoud A, Mohammed OB, Morgan AMA. Identification of potential drug target in malarial disease using molecular docking analysis. Saudi J Biol Sci 2020; 27:3327-3333. [PMID: 33304138 PMCID: PMC7715035 DOI: 10.1016/j.sjbs.2020.10.019] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/03/2020] [Revised: 10/10/2020] [Accepted: 10/11/2020] [Indexed: 11/27/2022] Open
Abstract
Malaria caused by genus Plasmodium, is a parasite which is the main health issue for humans and about half of the population were suffered. An every year, approximately 1.2–2.7 million people died due to malaria globally. Therefore to prevent the spreading of malaria from the glob novel active drugs with specific activities are necessary. The present study aimed to identify novel drug molecule together with the bioinformatic tools for the development of active malarial drugs. As the search for latest anti malarial compound was developed, this work determined six active blends from various drug databases which possess drug-like characteristics and presents a significant anti malarial actions in in-silico level. Compound ID 300238, 889, 76569, 87324, 45678, and Z185397112are a few of the ligands were got from the Toss lab, Maybridge, Cambridge, Life chem, Bitter, and Examine drug databases and docked against hexokinase 1 protein (PDB: 1CZA) with high throughput practical screening (HTVS) using Glide v6.6. Amid the 6 compounds, compound no: 300238 from Toss lab has the greatest docking score of −9.889 kcal/mol targeting 1CZA protein. The active sites of Hexokinase I of protein were determine by using superimposition of the destination and template structure showed similar structural folds and active sites which were decidedly conserved. The quality of hexokinase I protein was considered to be sterically stable where the protein was prepared by utilizing the software protein preparation execute in the Schrodinger suite. Prepared proteins were evaluated using SAVES and the studies of molecular dynamics of the hexokinase, and the GROMACS were performed for protein–ligand complex. The low HOMO-LUMO energy gaps of the compound verified the greater stability of the molecule. Here, the tested drug candidates have good absorption, distribution, metabolism, and excretion (ADME) properties which were established by using QikProp, version 3.4 of Schrodinger.
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Affiliation(s)
| | | | | | - Dhamodharan Prabhu
- Department of Bioinformatics, Alagappa University, Karaikudi, Tamil Nadu 630 003, India
| | - Ravi Guru Raj Rao
- Department of Bioinformatics, Alagappa University, Karaikudi, Tamil Nadu 630 003, India
| | - Jeyaraman Jeyakanthan
- Department of Bioinformatics, Alagappa University, Karaikudi, Tamil Nadu 630 003, India
| | - Ahmed Hossam Mahmoud
- Department Zoology, College of Science, King Saud University, P.O Box 2455, Riyadh 11451, Saudi Arabia
| | - Osama B Mohammed
- Department Zoology, College of Science, King Saud University, P.O Box 2455, Riyadh 11451, Saudi Arabia
| | - Abubaker M A Morgan
- Faculty of Agricultural Sciences, University of Gezira, Wad-Medani, P.O Box 20, Sudan
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4
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Du L, Han Y, Zhang H, Zhang Y, Zhao J, Liang Y. Synthesis of 1
H
‐Pyrrolo[1,2‐
a
]indoles
via
Lewis Acid‐Catalyzed Annulation of Propargylic Alcohols with 2‐Ethynylanilines. Adv Synth Catal 2020. [DOI: 10.1002/adsc.201901409] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/25/2022]
Affiliation(s)
- Li‐Juan Du
- School of Chemical Engineering and TechnologyHebei University of Technology Tianjin 300130 People's Republic of China
| | - Ya‐Ping Han
- School of Chemical Engineering and TechnologyHebei University of Technology Tianjin 300130 People's Republic of China
| | - Hong‐Yu Zhang
- School of Chemical Engineering and TechnologyHebei University of Technology Tianjin 300130 People's Republic of China
| | - Yuecheng Zhang
- School of Chemical Engineering and TechnologyHebei University of Technology Tianjin 300130 People's Republic of China
| | - Jiquan Zhao
- School of Chemical Engineering and TechnologyHebei University of Technology Tianjin 300130 People's Republic of China
| | - Yong‐Min Liang
- State Key Laboratory of Applied Organic ChemistryLanzhou University Lanzhou 730000 People's Republic of China
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5
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Helton LG, Kennedy EJ. Targeting Plasmodium with constrained peptides and peptidomimetics. IUBMB Life 2020; 72:1103-1114. [PMID: 32037730 DOI: 10.1002/iub.2244] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/09/2019] [Accepted: 01/24/2020] [Indexed: 01/04/2023]
Abstract
Malaria remains a worldwide health concern with an estimated quarter of a billion people infected and nearly half a million deaths annually. Malaria is caused by a parasite infection from Plasmodium strains which are transmitted from mosquitoes into the human host. Although several small molecule inhibitors have been found to target the early stages of transmission and prevent parasite proliferation, multiple drug resistant parasite strains have emerged and drug resistance remains a major hurdle. As an alternative to small molecule inhibition, several peptide-based therapeutics have been explored for their potential as antimalarial compounds. Chemically constrained peptides or peptidomimetics were developed to target large binding interfaces of parasite-based proteins that have historically been difficult to selectively inhibit using small molecules. Here, we review ongoing research aimed at developing constrained peptides targeting protein-protein interactions pertinent to malaria pathogenesis. These targets include Falcipain-2, the J domain of CDPK1, myosin A tail domain interacting protein, the PKA signaling pathway, and an unclear signaling pathway involving angiotensin-derived peptides. Diverse synthetic methods were also used for each target. Merging parasite biology with synthetic strategies may provide new opportunities to develop alternative methods for uncovering novel antimalarials and may offer an alternate source for targeting drug-resistant parasite strains.
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Affiliation(s)
- Leah G Helton
- Department of Pharmaceutical and Biomedical Sciences, College of Pharmacy, University of Georgia, Athens, Georgia
| | - Eileen J Kennedy
- Department of Pharmaceutical and Biomedical Sciences, College of Pharmacy, University of Georgia, Athens, Georgia
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6
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Feng LS, Xu Z, Chang L, Li C, Yan XF, Gao C, Ding C, Zhao F, Shi F, Wu X. Hybrid molecules with potential in vitro antiplasmodial and in vivo antimalarial activity against drug-resistant Plasmodium falciparum. Med Res Rev 2019; 40:931-971. [PMID: 31692025 DOI: 10.1002/med.21643] [Citation(s) in RCA: 39] [Impact Index Per Article: 7.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/04/2019] [Revised: 09/16/2019] [Accepted: 10/08/2019] [Indexed: 12/12/2022]
Abstract
Malaria is a tropical disease, leading to around half a million deaths annually. Antimalarials such as quinolines are crucial to fight against malaria, but malaria control is extremely challenged by the limited pipeline of effective pharmaceuticals against drug-resistant strains of Plasmodium falciparum which are resistant toward almost all currently accessible antimalarials. To tackle the growing resistance, new antimalarial drugs are needed urgently. Hybrid molecules which contain two or more pharmacophores have the potential to overcome the drug resistance, and hybridization of quinoline privileged antimalarial building block with other antimalarial pharmacophores may provide novel molecules with enhanced in vitro and in vivo activity against drug-resistant (including multidrug-resistant) P falciparum. In recent years, numerous of quinoline hybrids were developed, and their activities against a panel of drug-resistant P falciparum strains were screened. Some of quinoline hybrids were found to possess promising in vitro and in vivo potency. This review emphasized quinoline hybrid molecules with potential in vitro antiplasmodial and in vivo antimalarial activity against drug-resistant P falciparum, covering articles published between 2010 and 2019.
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Affiliation(s)
| | - Zhi Xu
- Guizhou University of Traditional Chinese Medicine, Guiyang, China
| | - Le Chang
- WuXi AppTec Co, Ltd, Wuhan, China
| | - Chuan Li
- WuXi AppTec Co, Ltd, Wuhan, China
| | | | | | | | | | - Feng Shi
- WuXi AppTec Co, Ltd, Wuhan, China
| | - Xiang Wu
- WuXi AppTec Co, Ltd, Wuhan, China
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7
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Biosca A, Dirscherl L, Moles E, Imperial S, Fernàndez-Busquets X. An ImmunoPEGliposome for Targeted Antimalarial Combination Therapy at the Nanoscale. Pharmaceutics 2019; 11:pharmaceutics11070341. [PMID: 31315185 PMCID: PMC6680488 DOI: 10.3390/pharmaceutics11070341] [Citation(s) in RCA: 16] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/03/2019] [Revised: 06/27/2019] [Accepted: 07/11/2019] [Indexed: 12/15/2022] Open
Abstract
Combination therapies, where two drugs acting through different mechanisms are administered simultaneously, are one of the most efficient approaches currently used to treat malaria infections. However, the different pharmacokinetic profiles often exhibited by the combined drugs tend to decrease treatment efficacy as the compounds are usually eliminated from the circulation at different rates. To circumvent this obstacle, we have engineered an immunoliposomal nanovector encapsulating hydrophilic and lipophilic compounds in its lumen and lipid bilayer, respectively. The antimalarial domiphen bromide has been encapsulated in the liposome membrane with good efficiency, although its high IC50 of ca. 1 µM for living parasites complicates its use as immunoliposomal therapy due to erythrocyte agglutination. The conjugation of antibodies against glycophorin A targeted the nanocarriers to Plasmodium-infected red blood cells and to gametocytes, the sole malaria parasite stage responsible for the transmission from the human to the mosquito vector. The antimalarials pyronaridine and atovaquone, which block the development of gametocytes, have been co-encapsulated in glycophorin A-targeted immunoliposomes. The co-immunoliposomized drugs have activities significantly higher than their free forms when tested in in vitro Plasmodium falciparum cultures: Pyronaridine and atovaquone concentrations that, when encapsulated in immunoliposomes, resulted in a 50% inhibition of parasite growth had no effect on the viability of the pathogen when used as free drugs.
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Affiliation(s)
- Arnau Biosca
- Barcelona Institute for Global Health (ISGlobal, Hospital Clínic-Universitat de Barcelona), Rosselló 149-153, ES-08036 Barcelona, Spain
- Nanomalaria Group, Institute for Bioengineering of Catalonia (IBEC), The Barcelona Institute of Science and Technology, Baldiri Reixac 10-12, ES-08028 Barcelona, Spain
- Nanoscience and Nanotechnology Institute (IN2UB), University of Barcelona, Martí i Franquès 1, ES-08028 Barcelona, Spain
| | - Lorin Dirscherl
- Barcelona Institute for Global Health (ISGlobal, Hospital Clínic-Universitat de Barcelona), Rosselló 149-153, ES-08036 Barcelona, Spain
- Nanomalaria Group, Institute for Bioengineering of Catalonia (IBEC), The Barcelona Institute of Science and Technology, Baldiri Reixac 10-12, ES-08028 Barcelona, Spain
- Nanoscience and Nanotechnology Institute (IN2UB), University of Barcelona, Martí i Franquès 1, ES-08028 Barcelona, Spain
| | - Ernest Moles
- Children's Cancer Institute, Lowy Cancer Research Centre, UNSW Sydney, PO Box 81, Randwick, NSW 2031, Australia
- School of Women's and Children's Health, UNSW Sydney, Sydney, NSW 2052, Australia
| | - Santiago Imperial
- Nanoscience and Nanotechnology Institute (IN2UB), University of Barcelona, Martí i Franquès 1, ES-08028 Barcelona, Spain
- Department of Biochemistry and Molecular Biomedicine, University of Barcelona, Avda. Diagonal 643, ES-08028 Barcelona, Spain
| | - Xavier Fernàndez-Busquets
- Barcelona Institute for Global Health (ISGlobal, Hospital Clínic-Universitat de Barcelona), Rosselló 149-153, ES-08036 Barcelona, Spain.
- Nanomalaria Group, Institute for Bioengineering of Catalonia (IBEC), The Barcelona Institute of Science and Technology, Baldiri Reixac 10-12, ES-08028 Barcelona, Spain.
- Nanoscience and Nanotechnology Institute (IN2UB), University of Barcelona, Martí i Franquès 1, ES-08028 Barcelona, Spain.
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8
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Zhou J, Jiang X, He S, Jiang H, Feng F, Liu W, Qu W, Sun H. Rational Design of Multitarget-Directed Ligands: Strategies and Emerging Paradigms. J Med Chem 2019; 62:8881-8914. [PMID: 31082225 DOI: 10.1021/acs.jmedchem.9b00017] [Citation(s) in RCA: 155] [Impact Index Per Article: 31.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/06/2023]
Abstract
Due to the complexity of multifactorial diseases, single-target drugs do not always exhibit satisfactory efficacy. Recently, increasing evidence indicates that simultaneous modulation of multiple targets may improve both therapeutic safety and efficacy, compared with single-target drugs. However, few multitarget drugs are on market or in clinical trials, despite the best efforts of medicinal chemists. This article discusses the systematic establishment of target combination, lead generation, and optimization of multitarget-directed ligands (MTDLs). Moreover, we analyze some MTDLs research cases for several complex diseases in recent years and the physicochemical properties of 117 clinical multitarget drugs, with the aim to reveal the trends and insights of the potential use of MTDLs.
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Affiliation(s)
- Junting Zhou
- Department of Medicinal Chemistry , China Pharmaceutical University , Nanjing 211198 , People's Republic of China.,Department of Natural Medicinal Chemistry , China Pharmaceutical University , Nanjing , 211198 , People's Republic of China
| | - Xueyang Jiang
- Department of Medicinal Chemistry , China Pharmaceutical University , Nanjing 211198 , People's Republic of China.,Department of Natural Medicinal Chemistry , China Pharmaceutical University , Nanjing , 211198 , People's Republic of China
| | - Siyu He
- Department of Medicinal Chemistry , China Pharmaceutical University , Nanjing 211198 , People's Republic of China
| | - Hongli Jiang
- Department of Medicinal Chemistry , China Pharmaceutical University , Nanjing 211198 , People's Republic of China.,Department of Natural Medicinal Chemistry , China Pharmaceutical University , Nanjing , 211198 , People's Republic of China
| | - Feng Feng
- Department of Natural Medicinal Chemistry , China Pharmaceutical University , Nanjing , 211198 , People's Republic of China.,Jiangsu Food and Pharmaceutical Science College , Huaian 223003 , People's Republic of China
| | - Wenyuan Liu
- Department of Analytical Chemistry , China Pharmaceutical University , Nanjing 210009 , People's Republic of China
| | - Wei Qu
- Department of Natural Medicinal Chemistry , China Pharmaceutical University , Nanjing , 211198 , People's Republic of China
| | - Haopeng Sun
- Department of Medicinal Chemistry , China Pharmaceutical University , Nanjing 211198 , People's Republic of China
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9
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Ismail M, Du Y, Ling L, Li X. Artesunate-heparin conjugate based nanocapsules with improved pharmacokinetics to combat malaria. Int J Pharm 2019; 562:162-171. [DOI: 10.1016/j.ijpharm.2019.03.031] [Citation(s) in RCA: 28] [Impact Index Per Article: 5.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/02/2018] [Revised: 03/13/2019] [Accepted: 03/14/2019] [Indexed: 12/17/2022]
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10
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Chiwunze TE, Palakollu VN, Gill AA, Kayamba F, Thapliyal NB, Karpoormath R. A highly dispersed multi-walled carbon nanotubes and poly(methyl orange) based electrochemical sensor for the determination of an anti-malarial drug: Amodiaquine. MATERIALS SCIENCE & ENGINEERING. C, MATERIALS FOR BIOLOGICAL APPLICATIONS 2019; 97:285-292. [DOI: 10.1016/j.msec.2018.12.018] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/16/2018] [Revised: 11/05/2018] [Accepted: 12/06/2018] [Indexed: 10/27/2022]
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11
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Abstract
Heparin is one of the oldest drugs, which nevertheless remains in widespread clinical use as an inhibitor of blood coagulation. The history of its identification a century ago unfolded amid one of the most fascinating scientific controversies turning around the distribution of credit for its discovery. The composition, purification and structure-function relationship of this naturally occurring glycosaminoglycan regarding its classical role as anticoagulant will be dealt with before proceeding to discuss its therapeutic potential in, among other, inflammatory and infectious disease, cancer treatment, cystic fibrosis and Alzheimer's disease. The first bibliographic reference hit using the words 'nanomedicine' and 'heparin' is as recent as 2008. Since then, nanomedical applications of heparin have experienced an exponential growth that will be discussed in detail, with particular emphasis on its antimalarial activity. Some of the most intriguing potential applications of heparin nanomedicines will be exposed, such as those contemplating the delivery of drugs to the mosquito stages of malaria parasites.
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Affiliation(s)
| | - Elena Lantero
- Nanomalaria Group, Institute for Bioengineering of Catalonia (IBEC), The Barcelona Institute of Science and Technology, Baldiri Reixac 10-12, ES-08028 Barcelona, Spain.,Barcelona Institute for Global Health (ISGlobal), Barcelona Center for International Health Research (CRESIB, Hospital Clínic-Universitat de Barcelona), Rosselló 149-153, ES-08036 Barcelona, Spain
| | - Xavier Fernàndez-Busquets
- Nanomalaria Group, Institute for Bioengineering of Catalonia (IBEC), The Barcelona Institute of Science and Technology, Baldiri Reixac 10-12, ES-08028 Barcelona, Spain.,Barcelona Institute for Global Health (ISGlobal), Barcelona Center for International Health Research (CRESIB, Hospital Clínic-Universitat de Barcelona), Rosselló 149-153, ES-08036 Barcelona, Spain.,Nanoscience & Nanotechnology Institute (IN2UB), University of Barcelona, Martí i Franquès 1, ES-08028 Barcelona, Spain
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12
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Tuteja R. Unraveling the importance of the malaria parasite helicases. FEBS J 2017; 284:2592-2603. [DOI: 10.1111/febs.14109] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/01/2016] [Revised: 05/04/2017] [Accepted: 05/10/2017] [Indexed: 12/27/2022]
Affiliation(s)
- Renu Tuteja
- Parasite Biology Group; International Centre for Genetic Engineering and Biotechnology; New Delhi India
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13
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Urbán P, Ranucci E, Fernàndez-Busquets X. Polyamidoamine nanoparticles as nanocarriers for the drug delivery to malaria parasite stages in the mosquito vector. Nanomedicine (Lond) 2016; 10:3401-14. [PMID: 26582279 DOI: 10.2217/nnm.15.174] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/17/2023] Open
Abstract
Malaria is arguably one of the main medical concerns worldwide because of the numbers of people affected, the severity of the disease and the complexity of the life cycle of its causative agent, the protist Plasmodium spp. With the advent of nanoscience, renewed hopes have appeared of finally obtaining the long sought-after magic bullet against malaria in the form of a nanovector for the targeted delivery of antimalarial compounds exclusively to Plasmodium-infected cells, thus increasing drug efficacy and minimizing the induction of resistance to newly developed therapeutic agents. Polyamidoamine-derived nanovectors combine into a single chemical structure drug encapsulating capacity, antimalarial activity, low unspecific toxicity, specific targeting to Plasmodium, optimal in vivo activity and affordable synthesis cost. After having shown their efficacy in targeting drugs to intraerythrocytic parasites, now polyamidoamines face the challenge of spearheading a new generation of nanocarriers aiming at the malaria parasite stages in the mosquito vector.
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Affiliation(s)
- Patricia Urbán
- European Commission, Joint Research Centre, Institute for Health & Consumer Protection, via E. Fermi 2749, IT-21027, Ispra, Varese, Italy
| | - Elisabetta Ranucci
- Dipartimento di Chimica, Università degli Studi di Milano, via Golgi 19, IT-20133 Milano, Italy
| | - Xavier Fernàndez-Busquets
- Nanomalaria Group, Institute for Bioengineering of Catalonia (IBEC), Baldiri Reixac 10-12, ES-08028 Barcelona, Spain.,Barcelona Institute for Global Health (ISGlobal), Barcelona Center for International Health Research (CRESIB, Hospital Clínic-Universitat de Barcelona), Rosselló 149-153, ES-08036 Barcelona, Spain.,Nanoscience & Nanotechnology Institute (IN2UB), University of Barcelona, Martí i Franquès 1, ES-08028 Barcelona, Spain
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14
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Faidallah HM, Panda SS, Serrano JC, Girgis AS, Khan KA, Alamry KA, Therathanakorn T, Meyers MJ, Sverdrup FM, Eickhoff CS, Getchell SG, Katritzky AR. Synthesis, antimalarial properties and 2D-QSAR studies of novel triazole-quinine conjugates. Bioorg Med Chem 2016; 24:3527-39. [DOI: 10.1016/j.bmc.2016.05.060] [Citation(s) in RCA: 26] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/17/2016] [Revised: 05/23/2016] [Accepted: 05/28/2016] [Indexed: 10/24/2022]
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15
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Karakurt T, Dinçer M, Çetin F. Molecular structure and vibrational and chemical shift assignments of (4R)-5-eno-4,7-epidioxy-3,7-O-methyl-1,2-O-(S)-trichloroethylidene-5,6,8-trideoxy-α-D-threo-1,4-furano-4,7-diulo-octose by DFT and ab initio HF calculations. J STRUCT CHEM+ 2015. [DOI: 10.1134/s0022476615050108] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/23/2022]
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16
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Nanda Kumar Y, Jeyakodi G, Gunasekaran K, Jambulingam P. Computational screening and characterization of putative vaccine candidates of Plasmodium vivax. J Biomol Struct Dyn 2015; 34:1736-50. [PMID: 26338678 DOI: 10.1080/07391102.2015.1090344] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/02/2023]
Abstract
Plasmodium vivax is the most prevalent species of malaria affecting millions of people annually worldwide and demands effective interventions to develop a successful vaccine. In this milieu, we have dedicated noteworthy efforts to characterize the proteome of P. vivax to give a lead for the epitope-based vaccine development. Membrane proteins of P. vivax were collected from SWISS PROT database and 10 antigenic proteins were identified among them by in silico analysis using multiple servers. T-cell and B-cell epitopes were identified and their immunity was assessed. Their ability to trigger humoral and cell-mediated responses was determined. Three dimensional models were constructed for the antigenic proteins using Modeller, Phyre2, and Modloop tools and their quality was validated using PROCHECK and ProSA-web validation servers. Further, the binding affinity and molecular interactions of these antigenic proteins were characterized by performing protein-protein docking against transmission-blocking anti-malaria antibody Fab2A8 (PDB ID: 3S62) using Z-dock module of Discovery Studio 4.0. The presence of potential B & T-cell epitopes, major histocompatibility complex-binding sites, and their efficient interactions with Fab2A8 antibody suggests the use of predicted antigenic proteins for the construction of multi-epitope peptide vaccine against P. vivax.
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Affiliation(s)
- Y Nanda Kumar
- a Biomedical Informatics Centre, Vector Control Research Centre , Indian Council of Medical Research , Pondicherry 605006 , India
| | - G Jeyakodi
- a Biomedical Informatics Centre, Vector Control Research Centre , Indian Council of Medical Research , Pondicherry 605006 , India
| | - K Gunasekaran
- a Biomedical Informatics Centre, Vector Control Research Centre , Indian Council of Medical Research , Pondicherry 605006 , India
| | - P Jambulingam
- a Biomedical Informatics Centre, Vector Control Research Centre , Indian Council of Medical Research , Pondicherry 605006 , India
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17
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Jones RA, Panda SS, Hall CD. Quinine conjugates and quinine analogues as potential antimalarial agents. Eur J Med Chem 2015; 97:335-55. [PMID: 25683799 DOI: 10.1016/j.ejmech.2015.02.002] [Citation(s) in RCA: 57] [Impact Index Per Article: 6.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/03/2014] [Revised: 01/08/2015] [Accepted: 02/04/2015] [Indexed: 10/24/2022]
Abstract
Malaria is a tropical disease, prevalent in Southeast Asia and Africa, resulting in over half a million deaths annually; efforts to develop new antimalarial agents are therefore particularly important. Quinine continues to play a role in the fight against malaria, but quinoline derivatives are more widely used. Drugs based on the quinoline scaffold include chloroquine and primaquine, which are able to act against the blood and liver stages of the parasite's life cycle. The purpose of this review is to discuss reported biologically active compounds based on either the quinine or quinoline scaffold that may have enhanced antimalarial activity. The review emphasises hybrid molecules, and covers advances made in the last five years. The review is divided into three sections: modifications to the quinine scaffold, modifications to aminoquinolines and finally metal-containing antimalarial compounds.
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Affiliation(s)
- Rachel A Jones
- Center for Heterocyclic Compounds, University of Florida, Department of Chemistry, Gainesville, FL 32611-7200, USA.
| | - Siva S Panda
- Center for Heterocyclic Compounds, University of Florida, Department of Chemistry, Gainesville, FL 32611-7200, USA
| | - C Dennis Hall
- Center for Heterocyclic Compounds, University of Florida, Department of Chemistry, Gainesville, FL 32611-7200, USA
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Kalani K, Cheema HS, Tripathi H, Khan F, Daroker MP, Srivastava SK. QSAR-guided semi-synthesis and in vitro validation of antiplasmodial activity in ursolic acid derivatives. RSC Adv 2015. [DOI: 10.1039/c4ra13709d] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022] Open
Abstract
As a part of antimalarial drug discovery programme, a QSAR model was developed for the prediction of antiplasmodial activity in ursolic acid derivatives, followed by semi-synthesis of virtually active derivatives and their biological evaluation.
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Affiliation(s)
- Komal Kalani
- Medicinal Chemistry Department
- CSIR-Central Institute of Medicinal and Aromatic Plants
- Lucknow-226015
- India
- Academy of Scientific and Innovative Research (AcSIR)
| | - Harveer Singh Cheema
- Molecular Bioprospection Department
- CSIR-Central Institute of Medicinal and Aromatic Plants
- Lucknow-226015
- India
- Academy of Scientific and Innovative Research (AcSIR)
| | - Himanshu Tripathi
- Metabolic & Structural Biology Department
- CSIR-Central Institute of Medicinal and Aromatic Plants
- Lucknow-226015
- India
- Academy of Scientific and Innovative Research (AcSIR)
| | - Feroz Khan
- Metabolic & Structural Biology Department
- CSIR-Central Institute of Medicinal and Aromatic Plants
- Lucknow-226015
- India
- Academy of Scientific and Innovative Research (AcSIR)
| | - M. P. Daroker
- Molecular Bioprospection Department
- CSIR-Central Institute of Medicinal and Aromatic Plants
- Lucknow-226015
- India
- Academy of Scientific and Innovative Research (AcSIR)
| | - Santosh Kumar Srivastava
- Medicinal Chemistry Department
- CSIR-Central Institute of Medicinal and Aromatic Plants
- Lucknow-226015
- India
- Academy of Scientific and Innovative Research (AcSIR)
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Marques J, Moles E, Urbán P, Prohens R, Busquets MA, Sevrin C, Grandfils C, Fernàndez-Busquets X. Application of heparin as a dual agent with antimalarial and liposome targeting activities toward Plasmodium-infected red blood cells. NANOMEDICINE-NANOTECHNOLOGY BIOLOGY AND MEDICINE 2014; 10:1719-28. [DOI: 10.1016/j.nano.2014.06.002] [Citation(s) in RCA: 41] [Impact Index Per Article: 4.1] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/07/2014] [Revised: 05/28/2014] [Accepted: 06/04/2014] [Indexed: 02/06/2023]
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Panda SS, Ibrahim MA, Küçükbay H, Meyers MJ, Sverdrup FM, El-Feky SA, Katritzky AR. Synthesis and antimalarial bioassay of quinine - peptide conjugates. Chem Biol Drug Des 2014; 82:361-6. [PMID: 23497252 DOI: 10.1111/cbdd.12134] [Citation(s) in RCA: 36] [Impact Index Per Article: 3.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/15/2013] [Accepted: 03/01/2013] [Indexed: 11/28/2022]
Abstract
Amino acid and peptide conjugates of quinine were synthesized using microwave irradiation in 52-95% yields using benzotriazole methodology. The majority of these conjugates retain in vitro antimalarial activity with IC50 values below 100 nm, similar to quinine.
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Affiliation(s)
- Siva S Panda
- Center for Heterocyclic Compounds, Department of Chemistry, University of Florida, Gainesville, FL, 32611-7200, USA
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21
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Kalani K, Agarwal J, Alam S, Khan F, Pal A, Srivastava SK. In silico and in vivo anti-malarial studies of 18β glycyrrhetinic acid from Glycyrrhiza glabra. PLoS One 2013; 8:e74761. [PMID: 24086367 PMCID: PMC3782471 DOI: 10.1371/journal.pone.0074761] [Citation(s) in RCA: 53] [Impact Index Per Article: 4.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/16/2013] [Accepted: 08/06/2013] [Indexed: 11/19/2022] Open
Abstract
Malaria is one of the most prevailing fatal diseases causing between 1.2 and 2.7 million deaths all over the world each year. Further, development of resistance against the frontline anti-malarial drugs has created an alarming situation, which requires intensive drug discovery to develop new, more effective, affordable and accessible anti-malarial agents possessing novel modes of action. Over the past few years triterpenoids from higher plants have shown a wide range of anti-malarial activities. As a part of our drug discovery program for anti-malarial agents from Indian medicinal plants, roots of Glycyrrhizaglabra were chemically investigated, which resulted in the isolation and characterization of 18β-glycyrrhetinic acid (GA) as a major constituent. The in vitro studies against P. falciparum showed significant (IC50 1.69µg/ml) anti-malarial potential for GA. Similarly, the molecular docking studies showed adequate docking (LibDock) score of 71.18 for GA and 131.15 for standard anti-malarial drug chloroquine. Further, in silico pharmacokinetic and drug-likeness studies showed that GA possesses drug-like properties. Finally, in vivo evaluation showed a dose dependent anti-malarial activity ranging from 68–100% at doses of 62.5–250mg/kg on day 8. To the best of our knowledge this is the first ever report on the anti-malarial potential of GA. Further work on optimization of the anti-malarial lead is under progress.
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Affiliation(s)
- Komal Kalani
- Medicinal Chemistry Department, CSIR-Central Institute of Medicinal and Aromatic Plants, Lucknow, Uttar Pradesh, India
| | - Jyoti Agarwal
- Molecular Bioprospection Department, CSIR-Central Institute of Medicinal and Aromatic Plants, Lucknow, Uttar Pradesh, India
| | - Sarfaraz Alam
- Metabolic and Structural Biology Department, CSIR-Central Institute of Medicinal and Aromatic Plants, Lucknow, Uttar Pradesh, India
| | - Feroz Khan
- Metabolic and Structural Biology Department, CSIR-Central Institute of Medicinal and Aromatic Plants, Lucknow, Uttar Pradesh, India
| | - Anirban Pal
- Molecular Bioprospection Department, CSIR-Central Institute of Medicinal and Aromatic Plants, Lucknow, Uttar Pradesh, India
- * E-mail: (SKS); (AP)
| | - Santosh Kumar Srivastava
- Medicinal Chemistry Department, CSIR-Central Institute of Medicinal and Aromatic Plants, Lucknow, Uttar Pradesh, India
- * E-mail: (SKS); (AP)
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Wisedpanichkij R, Grams R, Chaijaroenkul W, Na-Bangchang K. Confutation of the existence of sequence-conserved cytochrome P450 enzymes in Plasmodium falciparum. Acta Trop 2011; 119:19-22. [PMID: 21510915 DOI: 10.1016/j.actatropica.2011.03.006] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/14/2011] [Revised: 03/11/2011] [Accepted: 03/21/2011] [Indexed: 10/18/2022]
Abstract
The aim of the present study was to find evidence for a homologous protein of the mammalian cytochrome P450 family member CYP2B1/B2 in Plasmodium falciparum at the nucleic acid level. Prior research had demonstrated enzyme activity in the parasite comparable to mammalian CYP1A, 2A, 2B and 2E enzymes and presence of CYP enzymes by spectrophotometric and electrophoretic analyses. In recent years, the transcriptome/proteome data of P. falciparum and other Plasmodium spp. have been published and we performed an in silico analysis to identify putative cytochrome P450 family members in the parasite. This analysis failed to identify homologs to CYP1A, 2A, 2B and 2E enzymes in Plasmodium. A prior study had also claimed the presence of a conserved CYP2B1/B2 gene in the parasite by using Northern analysis with a rat CYP2B1/B2 probe. We have repeated this analysis by cloning a rat CYP2B1/B2 cDNA and using it as a hybridization probe against total RNA extracted from P. falciparum K1 and 3D7 clones but did not obtain positive results. This is consistent with the transcriptome/proteome sequence data and suggests that the genus Plasmodium contains either only highly diverged CYP proteins which are not easily identified by their primary sequence or that they have been functionally replaced by other enzymes. It is suggested that further studies are performed that allow isolation and identification of such proteins through their functional activities.
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Perce-da-Silva DS, Banic DM, Lima-Junior JC, Santos F, Daniel-Ribeiro CT, de Oliveira-Ferreira J, Pratt-Riccio LR. Evaluation of allelic forms of the erythrocyte binding antigen 175 (EBA-175) in Plasmodium falciparum field isolates from Brazilian endemic area. Malar J 2011; 10:146. [PMID: 21615944 PMCID: PMC3138422 DOI: 10.1186/1475-2875-10-146] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/16/2010] [Accepted: 05/26/2011] [Indexed: 11/10/2022] Open
Abstract
BACKGROUND The Plasmodium falciparum Erythrocyte Binding Antigen-175 (EBA-175) is an antigen considered to be one of the leading malaria vaccine candidates. EBA-175 mediates sialic acid-dependent binding to glycophorin A on the erythrocytes playing a crucial role during invasion of the P. falciparum in the host cell. Dimorphic allele segments, termed C-fragment and F-fragment, have been found in high endemicity malaria areas and associations between the dimorphism and severe malaria have been described. In this study, the genetic dimorphism of EBA-175 was evaluated in P. falciparum field isolates from Brazilian malaria endemic area. METHODS The study was carried out in rural villages situated near Porto Velho, Rondonia State in the Brazilian Amazon in three time points between 1993 and 2008. The allelic dimorphism of the EBA-175 was analysed by Nested PCR. RESULTS The classical allelic dimorphism of the EBA-175 was identified in the studied area. Overall, C-fragment was amplified in a higher frequency than F-fragment. The same was observed in the three time points where C-fragment was observed in a higher frequency than F-fragment. Single infections (one fragment amplified) were more frequent than mixed infection (two fragments amplified). CONCLUSIONS These findings confirm the dimorphism of EBA175, since only the two types of fragments were amplified, C-fragment and F-fragment. Also, the results show the remarkable predominance of CAMP allele in the studied area. The comparative analysis in three time points indicates that the allelic dimorphism of the EBA-175 is stable over time.
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Affiliation(s)
- Daiana S Perce-da-Silva
- Laboratório de Pesquisas em Malária, Instituto Oswaldo Cruz, Fiocruz, Manguinhos, Rio de Janeiro, RJ - CEP: 21040-900 Brazil
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Development, evaluation, and application of an in silico model for antimalarial drug treatment and failure. Antimicrob Agents Chemother 2011; 55:3380-92. [PMID: 21537019 DOI: 10.1128/aac.01712-10] [Citation(s) in RCA: 36] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/18/2022] Open
Abstract
Pharmacological mechanism-based modeling was refined and used to develop an in silico model of antimalarial drug treatment validated against clinical and field data. We used this approach to investigate key features of antimalarial drug action and effectiveness, with emphasis on the current generation of artemisinin combination therapies. We made the following conclusions. (i) The development of artemisinin tolerance and resistance will, unless checked, have an immediate, large impact on the protection afforded to its partner drug and on the likely clinical efficacy of artemisinin combination therapies. (ii) Long follow-up periods are required in clinical trials to detect all drug failures; the follow-up periods of 28 days recommended by the World Health Organization are likely to miss at least 50% of drug failures, and we confirmed recent suggestions that 63 days would be a more appropriate follow-up period. (iii) Day 7 serum drug concentrations are a significant risk factor of failure, although, paradoxically, receiver operating characteristic curve analysis revealed that their predictive power is relatively poor. (iv) The pharmacokinetic properties of the partner drugs in artemisinin-containing combination therapies are the most important determinants of treatment outcome, particularly the maximum killing rate. We discuss the assumptions made in such modeling approaches and how similar approaches may be refined in future work.
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Schneider KA, Kim Y. Approximations for the hitchhiking effect caused by the evolution of antimalarial-drug resistance. J Math Biol 2010; 62:789-832. [PMID: 20623287 DOI: 10.1007/s00285-010-0353-9] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/22/2010] [Revised: 06/09/2010] [Indexed: 12/01/2022]
Abstract
An analytically feasible, deterministic model for the spread of drug resistance among human malaria parasites, which incorporates all characteristics of the complex malaria-transmission cycle was introduced by Schneider and Kim (Theor. Popul Biol, 2010). The model accounts for the fact that only a fraction of infected hosts receive drug treatment and that hosts can be co-infected by differently many parasites. Furthermore, the model also incorporates host heterogeneity. Antimalarial-drug resistance is assumed to be caused by a single locus with two alleles-a sensitive one and a resistance one. The most important result for this model is that an analytical solution for the frequencies of a linked neutral biallelic locus exists. However, the exact solution does not admit an explicit form, and cannot straightforwardly be interpreted in terms of the model parameters. Here, we establish simple approximations for the equilibrium frequency at the neutral locus. Under the assumption that the resistant allele is initially rare-the biologically most relevant assumption in this context-and that recombination is weak, the approximations become similar to the approximations in the standard hitchhiking model. However, there are crucial differences. In particular, because of the high degree of selfing among malaria parasites in their sexual phase, a genome-wide reduction of relative heterozygosity occurs if selection is sufficiently strong. It turns out that the approximations are accurate even if the recombination rates are not small and the resistant allele is initially not very rare. The main advantage of our approximations is that they are easy to interpret in terms of model parameters. Moreover, they allow to make predictions of the size of the valley of reduced heterozygosity around the selected locus for given model parameters. Reversely, for a given reduction of heterozygosity, it is possible to identify the corresponding parameters. Moreover, we will show that incorporating host heterogeneity leads to an increased hitchhiking effect.
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Affiliation(s)
- Kristan A Schneider
- School of Life Sciences, Arizona State University, 1711 South Rural Road, Tempe, AZ 85287, USA.
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Casano G, Dumètre A, Pannecouque C, Hutter S, Azas N, Robin M. Anti-HIV and antiplasmodial activity of original flavonoid derivatives. Bioorg Med Chem 2010; 18:6012-23. [PMID: 20638854 DOI: 10.1016/j.bmc.2010.06.067] [Citation(s) in RCA: 28] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/25/2010] [Revised: 06/10/2010] [Accepted: 06/21/2010] [Indexed: 10/19/2022]
Abstract
In our search for potent anti-HIV and antiplasmodial agents, novel series of flavonoid derivatives and their chalcone intermediates were synthesized and evaluated for inhibition of HIV multiplication and antiproliferative activity on Plasmodium falciparum parasites. Chalcones exhibited a more selective antiplasmodial activity than flavonoids. Methoxyflavone 7e was the only one compound active in both P. falciparum and HIV-1 whereas aminomethoxyflavones showed activity against HIV-2. Para substitution on the B ring seemed to increase HIV-2 potency.
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Affiliation(s)
- Gilles Casano
- Aix-Marseille Université, Institut des Sciences Moléculaires de Marseille, iSm2-UMR CNRS, Centre Saint Jérôme, Marseille Cedex 20, France
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27
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An analytical model for genetic hitchhiking in the evolution of antimalarial drug resistance. Theor Popul Biol 2010; 78:93-108. [PMID: 20600206 DOI: 10.1016/j.tpb.2010.06.005] [Citation(s) in RCA: 23] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/05/2009] [Revised: 06/04/2010] [Accepted: 06/07/2010] [Indexed: 11/21/2022]
Abstract
We analytically study a deterministic model for the spread of drug resistance among human malaria parasites. The model incorporates all major characteristics of the complex malaria transmission cycle and accounts for the fact that only a fraction alpha of infected hosts receive drug treatment. Furthermore, the model incorporates that hosts can be co-infected. The number m of parasites co-infecting a host is either a constant or, more generally, follows a given frequency distribution. Although the model is formulated in a multilocus setup, for our results we assume that drug resistance is caused by a single locus with two alleles - a sensitive one and a resistant one. We assume that the resistant allele has a selective advantage only in treated hosts and pays metabolic costs, which causes this allele to be deleterious in untreated hosts. We provide necessary and sufficient conditions for the fixation of the resistant allele. Moreover, provided the resistant allele will sweep through the population, we derive a formula for the time until it reaches a given frequency and in particular for the time until quasi-fixation. Furthermore, we establish an analytical solution for allele frequency changes at a linked neutral biallelic locus due to the rapid increase in frequency of the resistant allele. Our solution describes a local reduction in heterozygosity among parasite chromosomes around the resistant allele, the effect commonly referred to as the hitchhiking effect, as a function of alpha and m. The result therefore allows the investigation of selective sweep patterns under specific demographic settings. We find that the hitchhiking effect is similar but different from the standard model of genetic hitchhiking that assumes random mating and homogeneous selection. In particular, the process of recombination and selection cannot be decoupled. We further explain why standard hitchhiking theory cannot be applied to drug resistance in malaria. Furthermore, we will show that a genome-wide reduction in relative heterozygosity can occur provided a fraction of hosts is infected by a single parasite haplotype. Finally, we show how to incorporate host heterogeneity, and generalize our results to this biologically more realistic case.
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Pierson JT, Dumètre A, Hutter S, Delmas F, Laget M, Finet JP, Azas N, Combes S. Synthesis and antiprotozoal activity of 4-arylcoumarins. Eur J Med Chem 2010; 45:864-9. [DOI: 10.1016/j.ejmech.2009.10.022] [Citation(s) in RCA: 55] [Impact Index Per Article: 3.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/11/2009] [Revised: 10/09/2009] [Accepted: 10/15/2009] [Indexed: 11/28/2022]
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Bonazzi S, Barbaras D, Patiny L, Scopelliti R, Schneider P, Cole ST, Kaiser M, Brun R, Gademann K. Antimalarial and antitubercular nostocarboline and eudistomin derivatives: synthesis, in vitro and in vivo biological evaluation. Bioorg Med Chem 2010; 18:1464-76. [PMID: 20133138 DOI: 10.1016/j.bmc.2010.01.013] [Citation(s) in RCA: 22] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/30/2009] [Revised: 01/05/2010] [Accepted: 01/06/2010] [Indexed: 10/20/2022]
Abstract
The synthesis of nine nostocarboline derivatives with substitutions of the 2-methyl group by alkyl, aryl and functionalized residues, 10 symmetrical bis cationic dimers linking 6-Cl-norharmane through the 2-position and fifteen derivatives of the marine alkaloids eudistomin N and O is reported. These compounds were evaluated in vitro against four parasites (Trypanosoma brucei rhodesiense STIB 900, Trypanosoma cruzi Tulahuen C2C4, Leishmania donovani MHOM-ET-67/L82 axenic amastigotes, and Plasmodium falciparum K1 strain), against Mycobacterium tuberculosis H37Rv, Mycobacterium smegmatis mc(2)155 and Corynebacterium glutamicum ATCC13032, and cytotoxicity was determined against L6 rat myoblast cells. Nostocarboline and derivatives displayed potent and selective in vitro inhibition of P. falciparum with weak cytotoxicity. The dimers displayed submicromolar inhibition of L. donovani and T. brucei, and nanomolar activity against P. falciparum, albeit with pronounced cytotoxicity. One dimer showed a MIC(99) value against M. tuberculosis of 2.5 microg/ml. The alkylated eudistomin N and O derivatives displayed activities down to 18 nM against P. falciparum for N-Me Eudistomin N. Four dimers, nostocarboline and three eudostomin derivatives were evaluated in an in vivo Plasmodium berghei mouse model. No significant activity was observed for the dimers, but a 50% reduction in parasitaemia was observed at 4 x 50 mg/kg ip for nostocarboline.
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Affiliation(s)
- Simone Bonazzi
- Chemical Synthesis Laboratory (SB-ISIC-LSYNC), Swiss Federal Institute of Technology (EPFL), CH-1015 Lausanne, Switzerland
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30
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Martyn DC, Nijjar A, Celatka CA, Mazitschek R, Cortese JF, Tyndall E, Liu H, Fitzgerald MM, O’Shea TJ, Danthi S, Clardy J. Synthesis and antiplasmodial activity of novel 2,4-diaminopyrimidines. Bioorg Med Chem Lett 2010; 20:228-31. [DOI: 10.1016/j.bmcl.2009.10.133] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/11/2009] [Revised: 10/26/2009] [Accepted: 10/29/2009] [Indexed: 12/01/2022]
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Martyn DC, Cortese JF, Tyndall E, Dick J, Mazitschek R, Munoz B, Clardy J. Antiplasmodial activity of piperazine sulfonamides. Bioorg Med Chem Lett 2010; 20:218-21. [DOI: 10.1016/j.bmcl.2009.10.130] [Citation(s) in RCA: 16] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/31/2009] [Revised: 10/26/2009] [Accepted: 10/29/2009] [Indexed: 10/20/2022]
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Synthesis and in vitro DMPK profiling of a 1,2-dioxolane-based library with activity against Plasmodium falciparum. Bioorg Med Chem Lett 2009; 19:5657-60. [DOI: 10.1016/j.bmcl.2009.08.024] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/02/2009] [Revised: 08/04/2009] [Accepted: 08/05/2009] [Indexed: 11/24/2022]
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Fernandez LS, Buchanan MS, Carroll AR, Feng YJ, Quinn RJ, Avery VM. Flinderoles A-C: antimalarial bis-indole alkaloids from Flindersia species. Org Lett 2009; 11:329-32. [PMID: 19090698 DOI: 10.1021/ol802506n] [Citation(s) in RCA: 178] [Impact Index Per Article: 11.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Abstract
With the aim of finding new natural product antimalarials, the novel indole alkaloids flinderole A-C were found to have selective antimalarial activities with IC(50) values between 0.15-1.42 microM. Flinderole A was isolated from the Australian plant Flindersia acuminata and flinderoles B and C from the Papua New Guinean plant F. amboinensis. Flinderoles A-C contain an unprecedented rearranged skeleton compared to their related isomers of the borreverine class of compounds.
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Affiliation(s)
- Liza S Fernandez
- Eskitis Institute, Griffith University, Brisbane, QLD 4111 Australia
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Rider SD, Zhu G. An apicomplexan ankyrin-repeat histone deacetylase with relatives in photosynthetic eukaryotes. Int J Parasitol 2008; 39:747-54. [PMID: 19136004 DOI: 10.1016/j.ijpara.2008.11.012] [Citation(s) in RCA: 14] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/30/2008] [Revised: 11/21/2008] [Accepted: 11/23/2008] [Indexed: 11/19/2022]
Abstract
Cryptosporidium parvum is a member of the Apicomplexa that lacks a plastid and associated nuclear-encoded genes, which has hampered its use in evolutionary comparisons with algae and eliminated a pool of potentially useful drug targets. Here we show that apicomplexan parasites possess an unusual family of class II histone deacetylase (HDAC) proteins with orthologues that are present in other chromalveolates and primitive algae. A striking feature of these HDAC proteins is the presence of ankyrin repeats in the amino-terminus that appear to be required for enzyme activity. In vitro and in vivo analyses of the C. parvum orthologue indicate that this subclass of chromatin-remodelling proteins is targeted by the anti-cancer drug suberoylanilide hydroxamic acid and that these proteins are most likely involved in the essential process of H4 histone deacetylation that coincides with DNA replication. We propose that members of this novel class of histone deacetylase can serve as promising new targets for treatments against debilitating diseases such as cryptosporidosis, toxoplasmosis and malaria.
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Affiliation(s)
- S Dean Rider
- Department of Pathobiology, Texas A&M University, College Station, TX 77843, USA.
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Martyn DC, Ramirez AP, Beattie MJ, Cortese JF, Patel V, Rush MA, Woerpel KA, Clardy J. Synthesis of spiro-1,2-dioxolanes and their activity against Plasmodium falciparum. Bioorg Med Chem Lett 2008; 18:6521-4. [PMID: 18993067 DOI: 10.1016/j.bmcl.2008.10.083] [Citation(s) in RCA: 18] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/04/2008] [Revised: 10/08/2008] [Accepted: 10/10/2008] [Indexed: 10/21/2022]
Abstract
Artemisinin-derived compounds play an integral role in current malaria chemotherapy. Given the virtual certainty of emerging resistance, we have investigated spiro-1,2-dioxolanes as an alternative scaffold. The endoperoxide functionality was generated by the SnCl(4)-mediated annulation of a bis-silylperoxide and an alkene. The first set of eight analogs gave EC(50) values of 50-150 nM against Plasmodium falciparum 3D7 and Dd2 strains, except for the carboxylic acid analog. A second series, synthesized by coupling a spiro-1,2-dioxolane carboxylic acid to four separate amines, afforded the most potent compound (EC(50) approximately 5 nM).
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Affiliation(s)
- Derek C Martyn
- Broad Institute Infectious Diseases Initiative, 7 Cambridge Center, Cambridge, MA 02142, USA
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Walcourt A, Kurantsin-Mills J, Adenuga BB, Loyevsky M, Kassim OO, Gordeuk VR. Plasmodium falciparum: Activity of artemisinin against Plasmodium falciparum cultured in sickle trait hemoglobin AS and normal hemoglobin AA red blood cells. Exp Parasitol 2008; 120:381-4. [PMID: 18823976 DOI: 10.1016/j.exppara.2008.09.006] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/21/2008] [Revised: 07/08/2008] [Accepted: 09/01/2008] [Indexed: 01/17/2023]
Abstract
The presence of sickle hemoglobin causes accumulation of hemoglobin degradative products that favor oxidative reaction in erythrocytes. Artemisinin derivatives exert antiparasite effects through oxidative reactions within infected erythrocytes. Using [(3)H]-hypoxanthine incorporation, we therefore did an in vitro comparison of IC(50) values for artemisinin in Plasmodium falciparum-infected erythrocytes from sickle cell trait (AS) and normal (AA) individuals. IC(50) values for chloroquine served as control. Without drugs, parasite growth was similar in AA and AS erythrocytes. Gender, age and blood group of donors had no significant effects on parasite growth. IC(50) value for artemisinin was 27+/-14nM in AS (N=22) compared to 24+/-9nM (N=27) in AA erythrocytes (P=0.4). IC(50) values for chloroquine were also similar in AA (22+/-8nM) and AS (20+/-11nM) erythrocytes. These results show no evidence of elevated artemisinin activity on P. falciparum in AS erythrocytes in vitro.
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Affiliation(s)
- A Walcourt
- Department of Physiology & Biophysics, Howard University College of Medicine, 520 W Street, Seely G Mudd Building, NW, Washington, DC 20059, USA
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Potent and selective antiplasmodial activity of the cyanobacterial alkaloid nostocarboline and its dimers. Bioorg Med Chem Lett 2008; 18:4413-5. [DOI: 10.1016/j.bmcl.2008.06.049] [Citation(s) in RCA: 49] [Impact Index Per Article: 3.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/13/2008] [Revised: 06/11/2008] [Accepted: 06/15/2008] [Indexed: 11/18/2022]
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Feistel T, Hodson CA, Peyton DH, Landfear SM. An expression system to screen for inhibitors of parasite glucose transporters. Mol Biochem Parasitol 2008; 162:71-6. [PMID: 18708094 DOI: 10.1016/j.molbiopara.2008.07.005] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/14/2008] [Revised: 07/16/2008] [Accepted: 07/17/2008] [Indexed: 10/21/2022]
Abstract
Chemotherapy of parasitic protists is limited by general toxicity, high expense and emergence of resistance to currently available drugs. Thus methods to identify new leads for further drug development are increasingly important. Previously, glucose transporters have been validated as new drug targets for protozoan parasites including Plasmodium falciparum, Leishmania mexicana and Trypanosoma brucei. A recently derived glucose transporter null mutant (Deltalmgt) of L. mexicana was used to functionally express various heterologous glucose transporters including those from T. brucei THT1, P. falciparum PfHT and human GLUT1-resulting in recovery of growth of the Deltalmgt null mutant in glucose replete medium. This heterologous expression system can be employed to screen for compounds that retard growth by inhibiting the expressed glucose transporter. The ability of this expression system to identify specific glucose transporter inhibitors was demonstrated using 3-O-undec-10-enyl-d-glucose, a previously described specific inhibitor of PfHT.
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Affiliation(s)
- Torben Feistel
- Department of Molecular Microbiology and Immunology, Oregon Health & Science University, Portland, OR 97239, USA
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Krause PJ, Gewurz BE, Hill D, Marty FM, Vannier E, Foppa IM, Furman RR, Neuhaus E, Skowron G, Gupta S, McCalla C, Pesanti EL, Young M, Heiman D, Hsue G, Gelfand JA, Wormser GP, Dickason J, Bia FJ, Hartman B, Telford SR, Christianson D, Dardick K, Coleman M, Girotto JE, Spielman A. Persistent and relapsing babesiosis in immunocompromised patients. Clin Infect Dis 2008; 46:370-6. [PMID: 18181735 DOI: 10.1086/525852] [Citation(s) in RCA: 230] [Impact Index Per Article: 14.4] [Reference Citation Analysis] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/03/2022] Open
Abstract
BACKGROUND Human babesiosis is a tickborne malaria-like illness that generally resolves without complication after administration of atovaquone and azithromycin or clindamycin and quinine. Although patients experiencing babesiosis that is unresponsive to standard antimicrobial therapy have been described, the pathogenesis, clinical course, and optimal treatment regimen of such cases remain uncertain. METHODS We compared the immunologic status, clinical course, and treatment of 14 case patients who experienced morbidity or death after persistence of Babesia microti infection, despite repeated courses of antibabesial treatment, with those of 46 control subjects whose infection resolved after a single course of standard therapy. This retrospective case-control study was performed in southern New England, New York, and Wisconsin. RESULTS All case patients were immunosuppressed at the time of acute babesiosis, compared with <10% of the control subjects. Most case patients experienced B cell lymphoma and were asplenic or had received rituximab before babesial illness. The case patients were more likely than control subjects to experience complications, and 3 died. Resolution of persistent infection occurred in 11 patients after 2-10 courses of therapy, including administration of a final antimicrobial regimen for at least 2 weeks after babesia were no longer seen on blood smear. CONCLUSIONS Immunocompromised people who are infected by B. microti are at risk of persistent relapsing illness. Such patients generally require antibabesial treatment for >or=6 weeks to achieve cure, including 2 weeks after parasites are no longer detected on blood smear.
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Affiliation(s)
- Peter J Krause
- Division of Infectious Diseases, Connecticut Children's Medical Center, and Department of Pediatrics, University of Connecticut School of Medicine, Farmington, Connecticut 06106, USA.
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Totino PRR, Daniel-Ribeiro CT, Corte-Real S, de Fátima Ferreira-da-Cruz M. Plasmodium falciparum: erythrocytic stages die by autophagic-like cell death under drug pressure. Exp Parasitol 2007; 118:478-86. [PMID: 18226811 DOI: 10.1016/j.exppara.2007.10.017] [Citation(s) in RCA: 50] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/06/2007] [Revised: 10/16/2007] [Accepted: 10/30/2007] [Indexed: 01/20/2023]
Abstract
It has been reported that an apoptotic cell death process can occur with protozoans, but no consensus on Plasmodium susceptibility to apoptosis was reached till now. Thus, we evaluated if Plasmodium falciparum blood forms undergo apoptosis after in vitro pressure with chloroquine, S-nitroso-N-acetyl-penicillamine (SNAP) or staurosporine. Inhibition of parasite growth and loss of viability were observed in treated cultures by both light microscopy and flow cytometry. When DNA fragmentation was verified, only a small number of TUNEL-positive parasites was detected in treated cultures and pretreatment of parasite with a general caspase inhibitor was not able to prevent parasite death. Considering the lack of apoptotic characteristics and the observation of parasites with cytoplasmatic vacuolization by electron microscopy, we conclude that P. falciparum parasites under chloroquine, SNAP or staurosporine pressures do not die by apoptosis but by a process similar to autophagy. The autophagic pathway could be explored as an alternative target for the development of new antimalarial drugs.
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Affiliation(s)
- Paulo Renato Rivas Totino
- Laboratory of Malaria Research, Instituto Oswaldo Cruz, Fiocruz, Pavilhão Leônidas Deane, Manguinhos, 21045-900 Rio de Janeiro, RJ, Brazil
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Motoshima K, Hiwasa Y, Yoshikawa M, Fujimoto K, Tai A, Kakuta H, Sasaki K. Antimalarial Cation-dimers Synthesized in Two Steps from an Inexpensive Starting Material, Isonicotinic Acid. ChemMedChem 2007; 2:1527-32. [PMID: 17607684 DOI: 10.1002/cmdc.200700107] [Citation(s) in RCA: 23] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/07/2022]
Abstract
Malaria is one of the three major serious infectious diseases in the world. As the area affected by malaria includes a large proportion of developing countries, there is a need for new antimalarials that can be synthesized and supplied inexpensively. To generate low-cost antimalarials, the MAP series 6-10, bis-cation dimers, synthesized by amidating the carboxyl group of isonicotinic acid (11) with various amines and by cationizing the nitrogen atoms of the pyridine ring with the corresponding alkyl bromides, were designed. This design enabled expansion of the structural variations of bis-cation-type antimalarial compounds. The compounds bearing alkyl or phenyl groups in the amide moieties showed remarkable antimalarial activities in vitro. Moreover, 1,1'-(1,12-dodecanediyl)bis[4-[(buthylamino)carbonyl]pyridinium bromide], MAP-412 (6 d), exhibited a potent antimalarial activity (ED(50)=8.2 mg kg(-1)). Being prepared at low cost, our bis-cation-type antimalarial compounds may be useful as lead compounds for inexpensive antimalarials.
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Affiliation(s)
- Kazunori Motoshima
- Division of Pharmaceutical Sciences, Okayama University Graduate School of Medicine, Dentistry, and Pharmaceutical Sciences, 1-1-1, Tsushima-Naka, Okayama 700-8530, Japan
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A novel artemisinin-quinine hybrid with potent antimalarial activity. Bioorg Med Chem Lett 2007; 17:3599-602. [PMID: 17482816 DOI: 10.1016/j.bmcl.2007.04.054] [Citation(s) in RCA: 127] [Impact Index Per Article: 7.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/22/2007] [Revised: 04/16/2007] [Accepted: 04/18/2007] [Indexed: 11/22/2022]
Abstract
Artemisinin was reduced to dihydroartemisinin and coupled to a carboxylic acid derivative of quinine via an ester linkage. This novel hybrid molecule had potent activity against the 3D7 and (drug-resistant) FcB1 strains of Plasmodium falciparum in culture. The activity was superior to that of artemisinin alone, quinine alone, or a 1:1 mixture of artemisinin and quinine.
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Abstract
This perspective is the fifth in a series discussing drugs dropped from development in 2005, of which 11 were being developed for infectious diseases. Of these, eight were antivirals and were dropped in Phase II or III: Medivir's alovudine, Ono Pharmaceuticals' aplaviroc hydrochloride and Excite's immunotherapeutic Xcellerate for HIV; Boehringer Ingelheim's ciluprevir, ViroPharma's HCV-086, Isis Pharmaceuticals' antisense oligonucleotide ISIS-14803, Japan Tobacco's JTK-003 and Rigel's R803 for hepatitis C virus. The remaining discontinued anti-infective drugs were an antibacterial vaccine (Vical's anthrax vaccine), an antiseptic (YM Bioscience's Dermofural) and an antifungal formulation (MacroChem's topical econazole). The drugs are grouped by compound class and reasons for their failure are discussed in this article.
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Baniecki ML, Wirth DF, Clardy J. High-throughput Plasmodium falciparum growth assay for malaria drug discovery. Antimicrob Agents Chemother 2006; 51:716-23. [PMID: 17116676 PMCID: PMC1797774 DOI: 10.1128/aac.01144-06] [Citation(s) in RCA: 129] [Impact Index Per Article: 7.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022] Open
Abstract
New therapeutic agents for the treatment of malaria, the world's most deadly parasitic disease, are urgently needed. Malaria afflicts 300 to 500 million people and results in 1 to 2 million deaths annually, and more than 85% of all malaria-related mortality involves young children and pregnant women in sub-Saharan Africa. The emergence of multidrug-resistant parasites, especially in Plasmodium falciparum, has eroded the efficacy of almost all currently available therapeutic agents. The discovery of new drugs, including drugs with novel cellular targets, could be accelerated with a whole-organism high-throughput screen (HTS) of structurally diverse small-molecule libraries. The standard whole-organism screen is based on incorporation of [3H]hypoxanthine and has liabilities, such as limited throughput, high cost, multiple labor-intensive steps, and disposal of radioactive waste. Recently, screens have been reported that do not use radioactive incorporation, but their reporter signal is not robust enough for HTS. We report a P. falciparum growth assay that is technically simple, robust, and compatible with the automation necessary for HTS. The assay monitors DNA content by addition of the fluorescent dye 4',6-diamidino-2-phenylindole (DAPI) as a reporter of blood-stage parasite growth. This DAPI P. falciparum growth assay was used to measure the 50% inhibitory concentrations (IC50s) of a diverse set of known antimalarials. The resultant IC50s compared favorably with those obtained in the [3H]hypoxanthine incorporation assay. Over 79,000 small molecules have been tested for antiplasmodial activity using the DAPI P. falciparum growth assay, and 181 small molecules were identified as highly active against multidrug-resistant parasites.
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Affiliation(s)
- Mary Lynn Baniecki
- Department of Biological Chemistry and Molecular Pharmacology, Harvard Medical School, 240 Longwood Avenue, C-643, Boston, MA 02115, USA
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