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Suárez L, Kosar AJ, Dodd EL, Tazoo D, Lambert AC, Bohle DS. Soluble meso and deuteroporphyrin analogs of the malaria pigment hematin anhydride. J Inorg Biochem 2024; 252:112470. [PMID: 38218137 DOI: 10.1016/j.jinorgbio.2023.112470] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/11/2023] [Revised: 12/18/2023] [Accepted: 12/18/2023] [Indexed: 01/15/2024]
Abstract
Two soluble heme analogs of the insoluble malaria pigment hematin anhydride (HA, or β-hematin), [Fe(III)(protoporphyrin)]2, with either mesoporphyrin (MHA) or deuteroporphyrin (DHA) are characterized by elemental analysis, SEM, IR spectroscopy, electronic spectroscopy, paramagnetic 1H NMR spectroscopy and solution magnetic susceptibility. While prior single crystal and X-ray powder diffraction results indicate all three have a common propionate linked dimer motif, there is considerable solid state variation in the conformation. This is associated with enhanced solubility of MHA and DHA. As with HA, DHA undergoes thermally promoted reversible hydration/dehydration in the solid state. Solution 1H NMR studies of DHA suggest a high spin dimeric structure with the porphyrin methyls distributed between two isomers which are also present in the solid state. These soluble iron(III)porphyrin dimers allow for the first direct solution studies by NMR and UV-Vis spectroscopies of these key species. Taken together the results illustrate the importance and utility of varying the substituents on the periphery of the porphyrin for studying heme aggregation and malaria pigment formation.
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Affiliation(s)
- Liliana Suárez
- Department of Chemistry, McGill University, 801 Sherbrooke St. W., Montreal H3A 0B8, Canada
| | - Aaron J Kosar
- Department of Chemistry, McGill University, 801 Sherbrooke St. W., Montreal H3A 0B8, Canada
| | - Erin L Dodd
- Département de Chimie de l'UQAM, 2101, rue Jeanne-Mance, Montréal H2X 2J6, Canada
| | - Dagobert Tazoo
- Department of Chemistry, McGill University, 801 Sherbrooke St. W., Montreal H3A 0B8, Canada
| | | | - D Scott Bohle
- Department of Chemistry, McGill University, 801 Sherbrooke St. W., Montreal H3A 0B8, Canada.
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2
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Structure- and ligand-based drug design methods for the modeling of antimalarial agents: a review of updates from 2012 onwards. J Biomol Struct Dyn 2022; 40:10481-10506. [PMID: 34129805 DOI: 10.1080/07391102.2021.1932598] [Citation(s) in RCA: 6] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/16/2022]
Abstract
Malaria still persists as one of the deadliest infectious disease having a huge morbidity and mortality affecting the higher population of the world. Structure and ligand-based drug design methods like molecular docking and MD simulations, pharmacophore modeling, QSAR and virtual screening are widely used to perceive the accordant correlation between the antimalarial activity and property of the compounds to design novel dominant and discriminant molecules. These modeling methods will speed-up antimalarial drug discovery, selection of better drug candidates for synthesis and to achieve potent and safer drugs. In this work, we have extensively reviewed the literature pertaining to the use and applications of various ligand and structure-based computational methods for the design of antimalarial agents. Different classes of molecules are discussed along with their target interactions pattern, which is responsible for antimalarial activity. Communicated by Ramaswamy H. Sarma.
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3
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Olivier T, Loots L, Kok M, de Villiers M, Reader J, Birkholtz LM, Arnott GE, de Villiers KA. Adsorption to the Surface of Hemozoin Crystals: Structure-Based Design and Synthesis of Amino-Phenoxazine β-Hematin Inhibitors. ChemMedChem 2022; 17:e202200139. [PMID: 35385211 PMCID: PMC9119941 DOI: 10.1002/cmdc.202200139] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/16/2022] [Revised: 04/05/2022] [Indexed: 11/07/2022]
Abstract
In silico adsorption of eight antimalarials that inhibit β-hematin (synthetic hemozoin) formation identified a primary binding site on the (001) face, which accommodates inhibitors via formation of predominantly π-π interactions. A good correlation (r2 =0.64, P=0.017) between adsorption energies and the logarithm of β-hematin inhibitory activity was found for this face. Of 53 monocyclic, bicyclic and tricyclic scaffolds, the latter yielded the most favorable adsorption energies. Five new amino-phenoxazine compounds were pursued as β-hematin inhibitors based on adsorption behaviour. The 2-substituted phenoxazines show good to moderate β-hematin inhibitory activity (<100 μM) and Plasmodium falciparum blood stage activity against the 3D7 strain. N1 ,N1 -diethyl-N4 -(10H-phenoxazin-2-yl)pentane-1,4-diamine (P2a) is the most promising hit with IC50 values of 4.7±0.6 and 0.64±0.05 μM, respectively. Adsorption energies are predictive of β-hematin inhibitory activity, and thus the in silico approach is a beneficial tool for structure-based development of new non-quinoline inhibitors.
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Affiliation(s)
- Tania Olivier
- Department of Chemistry and Polymer Science, Stellenbosch University, Private BagX1, Matieland, 7602, South Africa
| | - Leigh Loots
- Department of Chemistry and Polymer Science, Stellenbosch University, Private BagX1, Matieland, 7602, South Africa
| | - Michélle Kok
- Department of Biochemistry, Stellenbosch University, Private BagX1, Matieland, 7602, South Africa
| | - Marianne de Villiers
- Department of Biochemistry, Stellenbosch University, Private BagX1, Matieland, 7602, South Africa
| | - Janette Reader
- Department of Biochemistry, Genetics and Microbiology, Institute for Sustainable Malaria Control, University of Pretoria, Pretoria, 0028, South Africa
| | - Lyn-Marié Birkholtz
- Department of Biochemistry, Genetics and Microbiology, Institute for Sustainable Malaria Control, University of Pretoria, Pretoria, 0028, South Africa
| | - Gareth E Arnott
- Department of Chemistry and Polymer Science, Stellenbosch University, Private BagX1, Matieland, 7602, South Africa
| | - Katherine A de Villiers
- Department of Chemistry and Polymer Science, Stellenbosch University, Private BagX1, Matieland, 7602, South Africa
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Singh B, Chetia D, Kumawat MK. Synthesis and In Vitro Antimalarial Activity Evaluation of Some New 1,2-Diaminopropane Side-Chain-Modified 4-Aminoquinoline Mannich Bases. Pharm Chem J 2021. [DOI: 10.1007/s11094-021-02484-z] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
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5
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Hisamatsu Y, Otani K, Takase H, Umezawa N, Higuchi T. Fluorescence Response and Self-Assembly of a Tweezer-Type Synthetic Receptor Triggered by Complexation with Heme and Its Catabolites. Chemistry 2021; 27:6489-6499. [PMID: 33026121 DOI: 10.1002/chem.202003872] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/21/2020] [Revised: 09/28/2020] [Indexed: 11/11/2022]
Abstract
There is increasing interest in the development and applications of synthetic receptors that recognize target biomolecules in aqueous media. We have developed a new tweezer-type synthetic receptor that gives a significant fluorescence response upon complexation with heme in aqueous solution at pH 7.4. The synthetic receptor consists of a tweezer-type heme recognition site and sulfo-Cy5 as a hydrophilic fluorophore. The receptor-heme complex exhibits a supramolecular amphiphilic character that facilitates the formation of self-assembled aggregates, and both the tweezer moiety and the sulfo-Cy5 moiety are important for this property. The synthetic receptor also exhibits significant fluorescence responses to biliverdin and bilirubin, but shows very weak fluorescence responses to flavin mononucleotide, folic acid, and nicotinamide adenine dinucleotide, which contain smaller π-scaffolds.
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Affiliation(s)
- Yosuke Hisamatsu
- Graduate School of Pharmaceutical Sciences, Nagoya City University, 3-1 Tanabe-dori, Mizuho-ku, Nagoya, 467-8603, Japan
| | - Koki Otani
- Graduate School of Pharmaceutical Sciences, Nagoya City University, 3-1 Tanabe-dori, Mizuho-ku, Nagoya, 467-8603, Japan
| | - Hiroshi Takase
- Graduate School of Medical Sciences, Nagoya City University, 1 Kawasumi, Mizuho-cho, Mizuho-ku, Nagoya, 467-8601, Japan
| | - Naoki Umezawa
- Graduate School of Pharmaceutical Sciences, Nagoya City University, 3-1 Tanabe-dori, Mizuho-ku, Nagoya, 467-8603, Japan
| | - Tsunehiko Higuchi
- Graduate School of Pharmaceutical Sciences, Nagoya City University, 3-1 Tanabe-dori, Mizuho-ku, Nagoya, 467-8603, Japan
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Traore O, Compaore M, Okusa P, Hubinon F, Duez P, Blankert B, Kindrebeogo M. Development and validation of an original magneto-chromatography device for the whole blood determination of hemozoin, the paramagnetic malaria pigment. Microchem J 2020. [DOI: 10.1016/j.microc.2020.105043] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/26/2023]
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Yadav DK, Kumar S, Teli MK, Yadav R, Chaudhary S. Molecular Targets for Malarial Chemotherapy: A Review. Curr Top Med Chem 2019; 19:861-873. [DOI: 10.2174/1568026619666190603080000] [Citation(s) in RCA: 10] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/20/2019] [Revised: 02/08/2019] [Accepted: 02/08/2019] [Indexed: 11/22/2022]
Abstract
The malaria parasite resistance to the existing drugs is a serious problem to the currently used
antimalarials and, thus, highlights the urgent need to develop new and effective anti-malarial molecules.
This could be achieved either by the identification of the new drugs for the validated targets or by further
refining/improving the existing antimalarials; or by combining previously effective agents with
new/existing drugs to have a synergistic effect that counters parasite resistance; or by identifying novel
targets for the malarial chemotherapy. In this review article, a comprehensive collection of some of the
novel molecular targets has been enlisted for the antimalarial drugs. The targets which could be deliberated
for developing new anti-malarial drugs could be: membrane biosynthesis, mitochondrial system,
apicoplasts, parasite transporters, shikimate pathway, hematin crystals, parasite proteases, glycolysis,
isoprenoid synthesis, cell cycle control/cycline dependent kinase, redox system, nucleic acid metabolism,
methionine cycle and the polyamines, folate metabolism, the helicases, erythrocyte G-protein, and
farnesyl transferases. Modern genomic tools approaches such as structural biology and combinatorial
chemistry, novel targets could be identified followed by drug development for drug resistant strains providing
wide ranges of novel targets in the development of new therapy. The new approaches and targets
mentioned in the manuscript provide a basis for the development of new unique strategies for antimalarial
therapy with limited off-target effects in the near future.
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Affiliation(s)
- Dharmendra K. Yadav
- College of Pharmacy, Gachon University of Medicine and Science, Hambakmoeiro, 191, Yeonsu-gu, Incheon 406-799, South Korea
| | - Surendra Kumar
- College of Pharmacy, Gachon University of Medicine and Science, Hambakmoeiro, 191, Yeonsu-gu, Incheon 406-799, South Korea
| | - Mahesh K. Teli
- College of Pharmacy, Gachon University of Medicine and Science, Hambakmoeiro, 191, Yeonsu-gu, Incheon 406-799, South Korea
| | - Ravikant Yadav
- Laboratory of Organic and Medicinal Chemistry, Department of Chemistry, Malaviya National Institute of Technology, Jawaharlal Nehru Marg, Jaipur-302017, India
| | - Sandeep Chaudhary
- Laboratory of Organic and Medicinal Chemistry, Department of Chemistry, Malaviya National Institute of Technology, Jawaharlal Nehru Marg, Jaipur-302017, India
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Roch A, Prodéo J, Pierart C, Muller RN, Duez P. The paramagnetic properties of malaria pigment, hemozoin, yield clues to a low-cost system for its trapping and determination. Talanta 2019; 197:553-557. [PMID: 30771975 DOI: 10.1016/j.talanta.2019.01.090] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/06/2018] [Revised: 01/22/2019] [Accepted: 01/24/2019] [Indexed: 11/27/2022]
Abstract
The binding of malaria pigment, hemozoin, by a gradient magnetic field has been investigated in a manual trapping column system. Two types of magnetic filling have been tested to produce field gradients: nickel-plated steel wires, wrapped around a steel core, and superparamagnetic microbeads. The latter system allows an efficient trapping (> 80%) of β-hematin (a synthetic pigment with physical and paramagnetic properties analogous to those of hemozoin). Tests with a Plasmodium falciparum 3D7 culture indicate that hemozoin is similarly trapped. Off-line optical spectroscopy measurements present limited sensitivity as the hemozoin we detected from in vitro cultured parasites would correspond to only a theoretical 0.02% parasitemia (1000 parasites/µL). Further work needs to be undertaken to reduce this threshold to a practical detectability level. Based on these data, a magneto-chromatographic on-line system with reduced dead volumes is proposed as a possible low-cost instrument to be tested as a malaria diagnosis system.
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Affiliation(s)
- A Roch
- Service de Chimie Générale, Organique et Biomédicale, Université de Mons (UMONS), Bât. Mendeleïev, Avenue Maistriau 19, 7000 Mons, Belgium
| | - J Prodéo
- Service de Chimie Générale, Organique et Biomédicale, Université de Mons (UMONS), Bât. Mendeleïev, Avenue Maistriau 19, 7000 Mons, Belgium
| | - C Pierart
- Service de Chimie Générale, Organique et Biomédicale, Université de Mons (UMONS), Bât. Mendeleïev, Avenue Maistriau 19, 7000 Mons, Belgium
| | - R N Muller
- Service de Chimie Générale, Organique et Biomédicale, Université de Mons (UMONS), Bât. Mendeleïev, Avenue Maistriau 19, 7000 Mons, Belgium
| | - P Duez
- Service de Chimie Thérapeutique et de Pharmacognosie, Université de Mons (UMONS), Bât. 6, Chemin du Champ de Mars 25, 7000 Mons, Belgium.
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Osman CP, Ismail NH, Widyawaruyanti A, Imran S, Tumewu L, Choo CY, Ideris S. Evaluation of a Series of 9,10-Anthraquinones as Antiplasmodial Agents. LETT DRUG DES DISCOV 2019. [DOI: 10.2174/1570180815666180607085102] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022]
Abstract
Background: A phytochemical study on medicinal plants used for the treatment of fever
and malaria in Africa yielded metabolites with potential antiplasmodial activity, many of which are
Anthraquinones (AQ). AQs have similar sub-structure as naphthoquinones and xanthones, which
were previously reported as novel antiplasmodial agents.
</P><P>
Objective: The present study aimed to investigate the structural requirements of 9,10-
anthraquinones with hydroxy, methoxy and methyl substituents to exert strong antiplasmodial activity
and to investigate their possible mode of action.
</P><P>
Methods: Thirty-one AQs were synthesized through Friedel-Crafts reaction and assayed for antiplasmodial
activity in vitro against Plasmodium falciparum (3D7). The selected compounds were
tested for toxicity and probed for their mode of action against β-hematin dimerization through
HRP2 and lipid catalyses. The most active compounds were subjected to a docking study using
AutoDock 4.2.
</P><P>
Results: The active AQs have similar common structural characteristics. However, it is difficult to
establish a structure-activity relationship as certain compounds are active despite the absence of the
structural features exhibited by other active AQs. They have either ortho- or meta-arranged
substituents and one free hydroxyl and/or carbonyl groups. When C-6 is substituted with a methyl
group, the activity of AQs generally increased. 1,3-DihydroxyAQ (15) showed good antiplasmodial
activity with an IC50 value of 1.08 µM, and when C-6 was substituted with a methyl group, 1,3-
dihydroxy-6-methylAQ (24) showed stronger antiplasmodial activity with an IC50 value of 0.02
µM, with better selectivity index. Compounds 15 and 24 showed strong HRP2 activity and mild
toxicity against hepatocyte cells. Molecular docking studies showed that the hydroxyl groups at the
ortho (23) and meta (24) positions are able to form hydrogen bonds with heme, of 3.49 Å and 3.02
Å, respectively.
</P><P>
Conclusion: The activity of 1,3-dihydroxy-6-methylAQ (24) could be due to their inhibition against
the free heme dimerization by inhibiting the HRP2 protein. It was further observed that the
anthraquinone moiety of compound 24 bind in parallel to the heme ring through hydrophobic interactions,
thus preventing crystallization of heme into hemozoin.
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Affiliation(s)
- Che Puteh Osman
- Faculty of Applied Sciences, Universiti Teknologi MARA, 40450 Shah Alam, Selangor, Malaysia
| | - Nor Hadiani Ismail
- Faculty of Applied Sciences, Universiti Teknologi MARA, 40450 Shah Alam, Selangor, Malaysia
| | - Aty Widyawaruyanti
- Department of Pharmacognosy and Phytochemistry, Faculty of Pharmacy, Universitas Airlangga, Surabaya 60286, Indonesia
| | - Syahrul Imran
- Faculty of Applied Sciences, Universiti Teknologi MARA, 40450 Shah Alam, Selangor, Malaysia
| | - Lidya Tumewu
- Department of Pharmacognosy and Phytochemistry, Faculty of Pharmacy, Universitas Airlangga, Surabaya 60286, Indonesia
| | - Chee Yan Choo
- MedChem Herbal Research Group, Faculty of Pharmacy, Universiti Teknologi MARA, 42300 Bandar Puncak Alam, Selangor, Malaysia
| | - Sharinah Ideris
- MedChem Herbal Research Group, Faculty of Pharmacy, Universiti Teknologi MARA, 42300 Bandar Puncak Alam, Selangor, Malaysia
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Agnello S, Brand M, Chellat MF, Gazzola S, Riedl R. A Structural View on Medicinal Chemistry Strategies against Drug Resistance. Angew Chem Int Ed Engl 2019; 58:3300-3345. [PMID: 29846032 DOI: 10.1002/anie.201802416] [Citation(s) in RCA: 37] [Impact Index Per Article: 7.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/27/2018] [Revised: 04/24/2018] [Indexed: 12/31/2022]
Abstract
The natural phenomenon of drug resistance is a widespread issue that hampers the performance of drugs in many major clinical indications. Antibacterial and antifungal drugs are affected, as well as compounds for the treatment of cancer, viral infections, or parasitic diseases. Despite the very diverse set of biological targets and organisms involved in the development of drug resistance, the underlying molecular mechanisms have been identified to understand the emergence of resistance and to overcome this detrimental process. Detailed structural information on the root causes for drug resistance is nowadays frequently available, so next-generation drugs can be designed that are anticipated to suffer less from resistance. This knowledge-based approach is essential for fighting the inevitable occurrence of drug resistance.
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Affiliation(s)
- Stefano Agnello
- Institute of Chemistry and Biotechnology, Center for Organic and Medicinal Chemistry, Zurich University of Applied Sciences (ZHAW), Einsiedlerstrasse 31, 8820, Wädenswil, Switzerland
| | - Michael Brand
- Institute of Chemistry and Biotechnology, Center for Organic and Medicinal Chemistry, Zurich University of Applied Sciences (ZHAW), Einsiedlerstrasse 31, 8820, Wädenswil, Switzerland
| | - Mathieu F Chellat
- Institute of Chemistry and Biotechnology, Center for Organic and Medicinal Chemistry, Zurich University of Applied Sciences (ZHAW), Einsiedlerstrasse 31, 8820, Wädenswil, Switzerland
| | - Silvia Gazzola
- Institute of Chemistry and Biotechnology, Center for Organic and Medicinal Chemistry, Zurich University of Applied Sciences (ZHAW), Einsiedlerstrasse 31, 8820, Wädenswil, Switzerland
| | - Rainer Riedl
- Institute of Chemistry and Biotechnology, Center for Organic and Medicinal Chemistry, Zurich University of Applied Sciences (ZHAW), Einsiedlerstrasse 31, 8820, Wädenswil, Switzerland
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Agnello S, Brand M, Chellat MF, Gazzola S, Riedl R. Eine strukturelle Evaluierung medizinalchemischer Strategien gegen Wirkstoffresistenzen. Angew Chem Int Ed Engl 2019. [DOI: 10.1002/ange.201802416] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/11/2022]
Affiliation(s)
- Stefano Agnello
- Institut für Chemie und Biotechnologie; FS Organische Chemie und Medizinalchemie; Zürcher Hochschule für Angewandte Wissenschaften (ZHAW); Einsiedlerstrasse 31 CH-8820 Wädenswil Schweiz
| | - Michael Brand
- Institut für Chemie und Biotechnologie; FS Organische Chemie und Medizinalchemie; Zürcher Hochschule für Angewandte Wissenschaften (ZHAW); Einsiedlerstrasse 31 CH-8820 Wädenswil Schweiz
| | - Mathieu F. Chellat
- Institut für Chemie und Biotechnologie; FS Organische Chemie und Medizinalchemie; Zürcher Hochschule für Angewandte Wissenschaften (ZHAW); Einsiedlerstrasse 31 CH-8820 Wädenswil Schweiz
| | - Silvia Gazzola
- Institut für Chemie und Biotechnologie; FS Organische Chemie und Medizinalchemie; Zürcher Hochschule für Angewandte Wissenschaften (ZHAW); Einsiedlerstrasse 31 CH-8820 Wädenswil Schweiz
| | - Rainer Riedl
- Institut für Chemie und Biotechnologie; FS Organische Chemie und Medizinalchemie; Zürcher Hochschule für Angewandte Wissenschaften (ZHAW); Einsiedlerstrasse 31 CH-8820 Wädenswil Schweiz
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Osman CP, Ismail NH. A REVIEW ON THE CHEMISTRY AND PHARMACOLOGY OF Rennellia elliptica Korth. INDONESIAN JOURNAL OF TROPICAL AND INFECTIOUS DISEASE 2017. [DOI: 10.20473/ijtid.v6i6.6642] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/26/2022] Open
Abstract
Rennellia elliptica, popularly dubbed as Malaysian Ginseng, is widely used in traditional medicine among the local Jakun community in Endau-Rompin State Park, Pahang, Malaysia. The decoction of the roots is traditionally taken for treatment of body aches, as postpartum tonic, as aphrodisiac and for the treatment of jaundice. In the effort of searching new botanical drugs and drug candidates from tropical rainforest, the team from this laboratory had conducted a sizeable phytochemical and biological screening program of tropical plant at Endau Rompin State Park, Pahang with the help from the indigenous people. R. elliptica showed strong antiplasmodial activity in vitro with the IC50 value of 4.04µg/mL. The comprehensive study on the root extract of R. elliptica in this laboratory yielded seventeen compounds from four different classes, including 2 new pyranoanthraquinones, one new anthraquinone, eleven known anthraquinones, one lactone triterpenoid, one coumarin and one phenolic acid. The chemical profile of the root extract was established using HPLC and the selected marker compounds were used as external standards and quantified using standard calibration curve. Nordamnacanthal 5, damnacanthal 7, 2-formyl-3-hydroxy-9,10-anthraquinone 6, 2-methyl-3-hydroxy-9,10-anthraquinone 11 and 1,2-dimethoxy-6-methyl-9,10-anthraquinone 3 were determined at 3.57, 10.32, 4.47, 12.18 and 4.09 µg/g, respectively. Owing to the toxicity of dichloromethane, the extraction of the desired marker compounds was attempted using accelerated solvent extraction and soxhlet extraction using ethanol and water at different compositions. R. elliptica root extract and the isolated anthraquinones showed potential antiplasmodial activity, and the active compounds were probed for their mode of action. In addition, the dichloromethane root extract of R. elliptica and the selected anthraquinones were screened for anticancer, antioxidant, and α-glucosidase inhibitory activities as well as toxicity study in vitro. The review summarizes the findings on Rennellia elliptica which includes phytochemistry, toxicity and its biological activities. The chemotaxonomic significance of Rennellia elliptica is also discussed
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Fitzroy SM, Gildenhuys J, Olivier T, Tshililo NO, Kuter D, de Villiers KA. The Effects of Quinoline and Non-Quinoline Inhibitors on the Kinetics of Lipid-Mediated β-Hematin Crystallization. LANGMUIR : THE ACS JOURNAL OF SURFACES AND COLLOIDS 2017; 33:7529-7537. [PMID: 28689414 PMCID: PMC5709178 DOI: 10.1021/acs.langmuir.7b01132] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/07/2023]
Abstract
The throughput of a biomimetic lipid-mediated assay used to investigate the effects of inhibitors on the kinetics of β-hematin formation has been optimized through the use of 24-well microplates. The rate constant for β-hematin formation mediated by monopalmitoyl-rac-glycerol was reduced from 0.17 ± 0.04 min-1 previously measured in Falcon tubes to 0.019 ± 0.002 min-1 in the optimized assay. While this necessitated longer incubation times, transferring aliquots from multiple 24-well plates to a single 96-well plate for final absorbance measurements actually improved the overall turnaround time per inhibitor. This assay has been applied to investigate the effects of four clinically relevant antimalarial drugs (chloroquine, amodiaquine, quinidine, and quinine) as well as several short-chain 4-aminoquinoline derivatives and non-quinoline (benzamide) compounds on the kinetics of β-hematin formation. The adsorption strength of these inhibitors to crystalline β-hematin (Kads) was quantified using a theoretical kinetic model that is based on the Avrami equation and the Langmuir isotherm. Statistically significant linear correlations between lipid-mediated β-hematin inhibitory activity and Kads values for quinoline (r2 = 0.76, P-value = 0.0046) and non-quinoline compounds (r2 = 0.99, P-stat = 0.0006), as well as between parasite inhibitory activity (D10) and Kads values for quinoline antimalarial drugs and short-chain chloroquine derivatives (r2 = 0.64, P-value = 0.0098), provide a strong indication that drug action involves adsorption to the surface of β-hematin crystals. Independent support in this regard is provided by experiments that spectrophotometrically monitor the direct adsorption of antimalarial drugs to preformed β-hematin.
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14
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Dodd EL, Tazoo D, Bohle DS. Solution and Solid State Correlations of Antimalarial Drug Actions: NMR and Crystallographic Studies of Drug Interactions with a Heme Model. Inorg Chem 2017. [PMID: 28650618 DOI: 10.1021/acs.inorgchem.7b00526] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Abstract
Solution NMR has been used in tandem with a diamagnetic non-iron heme model compound as a simple and effective tool to rapidly probe the structures of the bound complexes formed between the metalloporphyrin and antimalarial drugs from the 4-aminoquinoline, 4-methylenehydroxylquinoline, and 8-aminoquinoline subfamilies. The ability of gallium(III) protoporphyrin IX to mimic heme chemistry is exploited. The 4-aminoquinolines quinacrine and amodiaquine and two novel 3-halo chloroquine analogues are found to bind to the metalloporphyrin through hydrogen-bonding and stacking interactions, while halofantrine and the 4-methylenehydroxylquinolines, quinine and mefloquine bind through the alcohol group of the drug. In each case, detailed structural information is available from the NMR assessment. The mefloquine model is confirmed crystallographically. The 8-aminoquinoline primaquine does not interact strongly. These tools show promise for future applications in assessing antimalarials in preclinical development for heme-binding drug targets.
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Affiliation(s)
- Erin L Dodd
- Department of Chemistry, McGill University , Montreal, H3A OB8, Quebec, Canada
| | - Dagobert Tazoo
- Department of Chemistry, McGill University , Montreal, H3A OB8, Quebec, Canada
| | - D Scott Bohle
- Department of Chemistry, McGill University , Montreal, H3A OB8, Quebec, Canada
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15
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Ongarora DSB, Strydom N, Wicht K, Njoroge M, Wiesner L, Egan TJ, Wittlin S, Jurva U, Masimirembwa CM, Chibale K. Antimalarial benzoheterocyclic 4-aminoquinolines: Structure-activity relationship, in vivo evaluation, mechanistic and bioactivation studies. Bioorg Med Chem 2015; 23:5419-32. [PMID: 26264839 DOI: 10.1016/j.bmc.2015.07.051] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/27/2015] [Revised: 07/15/2015] [Accepted: 07/25/2015] [Indexed: 10/23/2022]
Abstract
A novel class of benzoheterocyclic analogues of amodiaquine designed to avoid toxic reactive metabolite formation was synthesized and evaluated for antiplasmodial activity against K1 (multidrug resistant) and NF54 (sensitive) strains of the malaria parasite Plasmodium falciparum. Structure-activity relationship studies led to the identification of highly promising analogues, the most potent of which had IC50s in the nanomolar range against both strains. The compounds further demonstrated good in vitro microsomal metabolic stability while those subjected to in vivo pharmacokinetic studies had desirable pharmacokinetic profiles. In vivo antimalarial efficacy in Plasmodium berghei infected mice was evaluated for four compounds, all of which showed good activity following oral administration. In particular, compound 19 completely cured treated mice at a low multiple dose of 4×10mg/kg. Mechanistic and bioactivation studies suggest hemozoin formation inhibition and a low likelihood of forming quinone-imine reactive metabolites, respectively.
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Affiliation(s)
- Dennis S B Ongarora
- Department of Chemistry, University of Cape Town, Rondebosch 7701, South Africa; South African Medical Research Council Drug Discovery and Development Research Unit, University of Cape Town, Rondebosch 7701, South Africa; Department of Pharmaceutical Chemistry, University of Nairobi, Nairobi, Kenya
| | - Natasha Strydom
- Department of Chemistry, University of Cape Town, Rondebosch 7701, South Africa
| | - Kathryn Wicht
- Department of Chemistry, University of Cape Town, Rondebosch 7701, South Africa
| | - Mathew Njoroge
- Department of Chemistry, University of Cape Town, Rondebosch 7701, South Africa; South African Medical Research Council Drug Discovery and Development Research Unit, University of Cape Town, Rondebosch 7701, South Africa
| | - Lubbe Wiesner
- Division of Clinical Pharmacology, Department of Medicine, University of Cape Town, Observatory 7925, South Africa
| | - Timothy J Egan
- Department of Chemistry, University of Cape Town, Rondebosch 7701, South Africa
| | - Sergio Wittlin
- Swiss Tropical and Public Health Institute, Socinstrasse 57, 4002 Basel, Switzerland; University of Basel, Socinstrasse 57, 4002 Basel, Switzerland
| | | | | | - Kelly Chibale
- Department of Chemistry, University of Cape Town, Rondebosch 7701, South Africa; Institute of Infectious Disease and Molecular Medicine, University of Cape Town, Rondebosch 7701, South Africa; South African Medical Research Council Drug Discovery and Development Research Unit, University of Cape Town, Rondebosch 7701, South Africa.
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16
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Singla P, Luxami V, Paul K. Triazine as a promising scaffold for its versatile biological behavior. Eur J Med Chem 2015; 102:39-57. [PMID: 26241876 DOI: 10.1016/j.ejmech.2015.07.037] [Citation(s) in RCA: 59] [Impact Index Per Article: 6.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/08/2015] [Revised: 07/19/2015] [Accepted: 07/20/2015] [Indexed: 12/19/2022]
Abstract
Among all heterocycles, the triazine scaffold occupies a prominent position, possessing a broad range of biological activities. Triazine is found in many potent biologically active molecules with promising biological potential like anti-inflammatory, anti-mycobacterial, anti-viral, anti-cancer etc. which makes it an attractive scaffold for the design and development of new drugs. The wide spectrum of biological activity of this moiety has attracted attention in the field of medicinal chemistry. Due to these biological activities, their structure-activity relationship has generated interest among medicinal chemists and this has culminated in the discovery of several lead molecules. The outstanding development of triazine derivatives in diverse diseases within very short span of time proves its magnitude for medicinal chemistry research. Therefore, these compounds have been synthesized as target structure by many researchers, and were further evaluated for their biological activities. In this review, we have compiled and discussed the biological potential of s-triazine derivatives, which could provide a low-height flying bird's eye view of the triazine derived compounds to a medicinal chemist, for a comprehensive and target oriented information for the development of clinically viable drugs.
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Affiliation(s)
- Prinka Singla
- School of Chemistry and Biochemistry, Thapar University, Patiala 147004, India
| | - Vijay Luxami
- School of Chemistry and Biochemistry, Thapar University, Patiala 147004, India
| | - Kamaldeep Paul
- School of Chemistry and Biochemistry, Thapar University, Patiala 147004, India.
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17
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Joubert JP, Smit FJ, du Plessis L, Smith PJ, N’Da DD. Synthesis and in vitro biological evaluation of aminoacridines and artemisinin–acridine hybrids. Eur J Pharm Sci 2014; 56:16-27. [DOI: 10.1016/j.ejps.2014.01.014] [Citation(s) in RCA: 25] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/04/2013] [Revised: 01/13/2014] [Accepted: 01/29/2014] [Indexed: 01/16/2023]
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18
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Cloete TT, de Kock C, Smith PJ, N'Da DD. Synthesis, in vitro antiplasmodial activity and cytotoxicity of a series of artemisinin–triazine hybrids and hybrid-dimers. Eur J Med Chem 2014; 76:470-81. [DOI: 10.1016/j.ejmech.2014.01.040] [Citation(s) in RCA: 25] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/11/2013] [Revised: 01/15/2014] [Accepted: 01/18/2014] [Indexed: 12/11/2022]
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19
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Synthesis, β-haematin inhibition, and in vitro antimalarial testing of isocryptolepine analogues: SAR study of indolo[3,2-c]quinolines with various substituents at C2, C6, and N11. Bioorg Med Chem 2014; 22:2629-42. [PMID: 24721829 DOI: 10.1016/j.bmc.2014.03.030] [Citation(s) in RCA: 51] [Impact Index Per Article: 5.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/31/2014] [Accepted: 03/17/2014] [Indexed: 11/23/2022]
Abstract
A series of indolo[3,2-c]quinolines were synthesized by modifying the side chains of the ω-aminoalkylamines at the C6 position and introducing substituents at the C2 position, such as F, Cl, Br, Me, MeO and NO2, and a methyl group at the N11 position for an SAR study. The in vitro antiplasmodial activities of the derivative agents against two different strains (CQS: NF54 and CQR: K1) and the cytotoxic activity against normal L6 cells were evaluated. The test results showed that compounds 6k and 6l containing the branched methyl groups of 3-aminopropylamino at C6 with a Cl atom at C2 exhibited a very low cytotoxicity with IC50 values above 4000 nM, high antimalarial activities with IC50 values of about 11 nM for CQS (NF54), IC50 values of about 17 nM for CQR (K1), and RI resistance indices of 1.6. Furthermore, the compounds were tested for β-haematic inhibition, and QSAR revealed an interesting linear correlation between the biological activity of CQS (NF54) and three contributing factors, namely solubility, hydrophilic surface area, and β-haematin inhibition for this series. In vivo testing of 6l showed a reduction in parasitaemia on day 4 with an activity of 38%.
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20
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RAMADHANI DWI, NURHAYATI SITI, RAHARDJO TUR. Haemozoin Detection in Mouse Liver Histology Using Simple Polarized Light Microscope. HAYATI JOURNAL OF BIOSCIENCES 2014. [DOI: 10.4308/hjb.21.1.48] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/11/2022] Open
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21
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Dodd EL, Bohle DS. Orienting the heterocyclic periphery: a structural model for chloroquine's antimalarial activity. Chem Commun (Camb) 2014; 50:13765-8. [DOI: 10.1039/c4cc05328a] [Citation(s) in RCA: 23] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
Abstract
A fluorescent structurally characterized chloroquine–metalloporphyrin adduct has been prepared and characterized. This allows for new insights into antimalarial drug–heme interactions.
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Affiliation(s)
- Erin L. Dodd
- Department of Chemistry
- McGill University
- Montreal, Canada
| | - D. Scott Bohle
- Department of Chemistry
- McGill University
- Montreal, Canada
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22
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Wang N, Wicht KJ, Shaban E, Ngoc TA, Wang MQ, Hayashi I, Hossain MI, Takemasa Y, Kaiser M, El Tantawy El Sayed I, Egan TJ, Inokuchi T. Synthesis and evaluation of artesunate–indoloquinoline hybrids as antimalarial drug candidates. MEDCHEMCOMM 2014. [DOI: 10.1039/c4md00091a] [Citation(s) in RCA: 36] [Impact Index Per Article: 3.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
Abstract
Hybrids of artesunate–indoloquinoline were synthesized and antiplasmodial activity was evaluated.
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Affiliation(s)
- Ning Wang
- Division of Chemistry and Biotechnology
- Graduate School of Natural Science and Technology
- Okayama University
- Kita-ku, Japan
| | - Kathryn J. Wicht
- Department of Chemistry
- University of Cape Town
- Rondebosch 7701, South Africa
| | - Elkhabiry Shaban
- Division of Chemistry and Biotechnology
- Graduate School of Natural Science and Technology
- Okayama University
- Kita-ku, Japan
| | - Tran Anh Ngoc
- Division of Chemistry and Biotechnology
- Graduate School of Natural Science and Technology
- Okayama University
- Kita-ku, Japan
| | - Ming-Qi Wang
- Division of Chemistry and Biotechnology
- Graduate School of Natural Science and Technology
- Okayama University
- Kita-ku, Japan
| | - Ikuya Hayashi
- Division of Chemistry and Biotechnology
- Graduate School of Natural Science and Technology
- Okayama University
- Kita-ku, Japan
| | - Md. Imran Hossain
- Division of Chemistry and Biotechnology
- Graduate School of Natural Science and Technology
- Okayama University
- Kita-ku, Japan
| | - Yoshihiko Takemasa
- Division of Chemistry and Biotechnology
- Graduate School of Natural Science and Technology
- Okayama University
- Kita-ku, Japan
| | - Marcel Kaiser
- Swiss Tropical and Public Health Institute
- CH-4002 Basel, Switzerland
- University Basel
- CH-4003 Basel, Switzerland
| | - Ibrahim El Tantawy El Sayed
- Division of Chemistry and Biotechnology
- Graduate School of Natural Science and Technology
- Okayama University
- Kita-ku, Japan
- Chemistry Departments
| | - Timothy J. Egan
- Department of Chemistry
- University of Cape Town
- Rondebosch 7701, South Africa
| | - Tsutomu Inokuchi
- Division of Chemistry and Biotechnology
- Graduate School of Natural Science and Technology
- Okayama University
- Kita-ku, Japan
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23
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Solomon VR, Haq W, Srivastava K, Puri SK, Katti SB. Design and synthesis of 3-[(7-chloro-1-oxidoquinolin-4-ylamino)alkyl]-1,3-thiazolidin-4-ones as antimalarial agents. J Enzyme Inhib Med Chem 2012; 28:1048-53. [PMID: 22957722 DOI: 10.3109/14756366.2012.710848] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/13/2022] Open
Abstract
A new series of quinoline analogs have been synthesized and found active against P. falciparum in vitro and P. yoelli in vivo. Compounds 8, 10 and 11 exhibited superior in vitro activity compared to chloroquine. Selected compounds 8, 10 and 11 exhibited significant suppression of parasitaemia in vivo assay. These analogs form a complex with hematin and inhibit the β-hematin formation, suggesting that this class of compounds act on a heme polymerization target. Further this study confirms that quinoline ring nitrogen is essential for both transportation of the molecule across the membrane as well as for tight binding to hematin.
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Affiliation(s)
- V Raja Solomon
- Division of Medicinal and Process Chemistry, Central Drug Research Institute , Lucknow , India
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24
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Blank O, Davioud-Charvet E, Elhabiri M. Interactions of the antimalarial drug methylene blue with methemoglobin and heme targets in Plasmodium falciparum: a physico-biochemical study. Antioxid Redox Signal 2012; 17:544-54. [PMID: 22256987 DOI: 10.1089/ars.2011.4239] [Citation(s) in RCA: 28] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/13/2022]
Abstract
AIMS Resistance of Plasmodium falciparum to drugs has led to renewed interest of redox-active methylene blue (MB) for which no resistance has been reported so far. Moreover, MB displays unique interactions with glutathione reductase (GR). However, the mechanisms of action/interaction with potential targets of MB are yet to be elucidated. Our physico-biochemical study on MB and relevant hematin-containing targets was performed under quasi-physiological conditions. RESULTS The water deprotonation of the Fe(III)protoporphyrin dimer, the major building block of β-hematin, was studied. At pH 6, the predominant dimer possesses water coordinated to both metals. Below pH 6, spontaneous precipitation of β-hematin occurred reminiscent of hemozoin biomineralization at pH 5.0-5.5 in the food vacuole of the malarial parasite. MB also forms dimers (K(Dim)=6800 M(-1)) and firmly binds to hematin in a 2:1 hematin:MB sandwich complex (K(D)=3.16 μM). MB bioactivation catalyzed by GR induces efficient methemoglobin(Fe(III)) [metHb(Fe(III))] reduction to hemoglobin(Fe(II)). The reduction rate, mediated by leucomethylene blue (LMB), was determined (k(metHb)(red)=991 M(-1)·s(-1)) in an assay coupled to the GR/reduced form of nicotinamide adenine dinucleotide phosphate system. INNOVATION AND CONCLUSION Our work provides new insights into the understanding of (i) how MB interacts with hematin-containing targets, (ii) other relevant MB properties in corroboration with the distribution of the three major LMB species as a function of pH, and (iii) how this redox-active cycler induces efficient catalytic reduction of metHb(Fe(III)) to hemoglobin(Fe(II)) mediated by oxidoreductases. These physico-biochemical parameters of MB open promising perspectives for the interpretation of the pharmacology and pathophysiology of malaria and possibly new routes for antimalarial drug development.
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Affiliation(s)
- Olga Blank
- Laboratoire de Chimie Bioorganique et Médicinale, European School of Chemistry, Polymers and Materials (ECPM), University of Strasbourg and Centre National de la Recherche Scientifique, Strasbourg, France
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25
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Synthesis, antimalarial activity and cytotoxicity of 10-aminoethylether derivatives of artemisinin. Bioorg Med Chem 2012; 20:4701-9. [DOI: 10.1016/j.bmc.2012.06.014] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/04/2012] [Revised: 05/29/2012] [Accepted: 06/05/2012] [Indexed: 11/22/2022]
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26
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van Heerden L, Cloete TT, Breytenbach JW, de Kock C, Smith PJ, Breytenbach JC, N'Da DD. Synthesis and in vitro antimalarial activity of a series of bisquinoline and bispyrrolo[1,2a]quinoxaline compounds. Eur J Med Chem 2012; 55:335-45. [PMID: 22889556 DOI: 10.1016/j.ejmech.2012.07.037] [Citation(s) in RCA: 33] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/18/2012] [Revised: 06/29/2012] [Accepted: 07/19/2012] [Indexed: 10/28/2022]
Abstract
Series of bisquinolines 4-15 and bispyrrolo[1,2a]quinoxalines 16-20 containing various polyamine linkers were synthesized. The aqueous solubility and distribution coefficient were experimentally determined. The compounds were screened for antimalarial activity alongside chloroquine against D10 and Dd2 strains of Plasmodium falciparum. The growth inhibitory effects of biscompounds 4-9 were assessed against various cancer cell lines. The aqueous solubility was found to increase with an increase in potential protonation sites. Bisquinolines 8 and 9 featuring triethylenetetramine and N,N'-bis(3-aminopropyl)ethylene-diamine linkers, respectively, were the most active of all synthesized compounds. They were found as potent as chloroquine against D10 but significantly more potent against the Dd2 strain, with good selectivity towards parasitic cells. Compound 4 containing a diethylenetriamine bridge displayed the most important anticancer activity of the series, and was a more effective antiproliferative inhibitor than etoposide against all three TK10, UACC62 and MCF7 cancer cell lines.
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Affiliation(s)
- Lezanne van Heerden
- Department of Pharmaceutical Chemistry, North-West University, Potchefstroom 2520, South Africa
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27
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Vargas S, Ndjoko Ioset K, Hay AE, Ioset JR, Wittlin S, Hostettmann K. Screening medicinal plants for the detection of novel antimalarial products applying the inhibition of β-hematin formation. J Pharm Biomed Anal 2011; 56:880-6. [PMID: 21872416 DOI: 10.1016/j.jpba.2011.06.026] [Citation(s) in RCA: 12] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/22/2011] [Revised: 06/27/2011] [Accepted: 06/28/2011] [Indexed: 10/18/2022]
Abstract
The identification of novel scaffolds for the development of effective and safe treatments to fight malaria is urgently needed. One of the main opportunities is the discovery of new molecules from natural origin. A simple, robust and cost-effective colorimetric assay based on the inhibition of β-hematin has been adapted to routinely screen plant extracts with the ultimate goal to identify novel antimalarial ingredients. The development of this assay has included a careful optimization of all critical experimental parameters. The β-hematin assay can be completed in less than one working day, requiring a 96-well UV-vis plate reader and low-cost commercially available reagents using a standard operating protocol. It can be used on its own or in combination with the well-known Plasmodium growth inhibition assay and has the obvious merit to be informative at the early stage of drug discovery regarding the mechanism of action of the actives. A total of 40 diverse natural products and 219 plants extracts were tested. Good correlations in respect with specificity (pure compounds 85%, extracts 93%) and positive predictive value (pure compounds 72%, extracts 50%) were obtained in comparison with Plasmodium growth inhibition assay that was used as the reference assay.
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Affiliation(s)
- S Vargas
- School of Pharmaceutical Sciences, University of Geneva, 1211 Geneva 4, Switzerland
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28
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Solomon VR, Haq W, Smilkstein M, Srivastava K, Puri SK, Katti SB. 4-Aminoquinoline derived antimalarials: synthesis, antiplasmodial activity and heme polymerization inhibition studies. Eur J Med Chem 2010; 45:4990-6. [PMID: 20805010 DOI: 10.1016/j.ejmech.2010.07.068] [Citation(s) in RCA: 29] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/03/2010] [Revised: 07/29/2010] [Accepted: 07/30/2010] [Indexed: 11/16/2022]
Abstract
A new series of 4-aminoquinoline derivatives have been synthesized and found to be active against both susceptible and resistant strains of Plasmodium falciparum in vitro. Compound 1-[3-(7-chloro-quinolin-4-ylamino)-propyl]-3-cyclopropyl-thiourea (7) exhibited superior in vitro activity against resistant strains of P. falciparum as compared to chloroquine (CQ). All the compounds showed resistance factor between 0.59 and 4.31 as against 5.05 for CQ. Spectroscopic studies suggested that this class of compounds act on heme polymerization target.
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Affiliation(s)
- V R Solomon
- Medicinal and Process Chemistry Division, Central Drug Research Institute, MG Road, Lucknow 226 001, India
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29
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Alesutan I, Bobbala D, Qadri SM, Estremera A, Föller M, Lang F. Beneficial effect of aurothiomalate on murine malaria. Malar J 2010; 9:118. [PMID: 20459650 PMCID: PMC2875225 DOI: 10.1186/1475-2875-9-118] [Citation(s) in RCA: 12] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/29/2009] [Accepted: 05/07/2010] [Indexed: 12/29/2022] Open
Abstract
Background Premature death of Plasmodium-infected erythrocytes is considered to favourably influence the clinical course of malaria. Aurothiomalate has previously been shown to trigger erythrocyte death or eryptosis, which is characterized by cell membrane scrambling leading to phosphatidylserine exposure at the cell surface. Phosphatidylserine-exposing cells are rapidly cleared from circulating blood. The present study thus tested whether sodium aurothiomalate influences the intraerythrocytic parasite development in vitro and the clinical course of murine malaria in vivo. Methods Human erythrocytes were infected with Plasmodium falciparum BinH in vitro and mice were infected (intraperitoneal injection of 1 × 106 parasitized murine erythrocytes) with Plasmodium berghei ANKA in vivo. Results Exposure to aurothiomalate significantly decreased the in vitro parasitemia of P. falciparum-infected human erythrocytes without influencing the intraerythrocytic DNA/RNA content. Administration of sodium aurothiomalate in vivo (daily 10 mg/kg b.w. s.c. from the 8th day of infection) enhanced the percentage of phosphatidylserine-exposing infected and noninfected erythrocytes in blood. All nontreated mice died within 30 days of infection. Aurothiomalate-treatment delayed the lethal course of malaria leading to survival of more than 50% of the mice 30 days after infection. Conclusions Sodium aurothiomalate influences the survival of Plasmodium berghei-infected mice, an effect only partially explained by stimulation of eryptosis.
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Affiliation(s)
- Ioana Alesutan
- Department of Physiology, University of Tübingen, Gmelinstr, 5, 72076 Tübingen, Germany
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30
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Abstract
Malaria, particularly that one caused by Plasmodium falciparum, remains a serious health problem in Africa, South America, and many parts of Asia where it afflicts about 500 million people and is responsible for the death of more than one million children each year. The main reasons for the persistence of malaria are the emergence of resistance to common antimalarial drugs, inadequate control of mosquito vectors, and the lack of effective vaccines. Therefore, the identification and characterization of new targets for antimalarial chemotherapy are of urgent priority. This review is focused on inhibitors of falcipain-2, a cysteine protease from P. falciparum, which represents one of the most promising targets for antimalarial drug design. Falcipain-2 is a key enzyme in the life cycle of P. falciparum since it degrades hemoglobin, at the early trophozoite stage, and cleaves ankyrin and protein 4.1, the cytoskeletal elements vital to the stability of red cell membrane, at the schizont stage. The main classes of falcipain-2 inhibitors are peptides or peptidomimetics bearing the most popular pharmacophores of cysteine protease inhibitors, such as vinyl sulfones, halomethyl ketones, and aldehydes. Furthermore, many other chemotypes have been identified as inhibitors of falcipain-2, such as isoquinolines, thiosemicarbazones, and chalcones. These inhibitors represent all classes, which, to the best of our knowledge, have been disclosed in journal articles to date.
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Affiliation(s)
- Roberta Ettari
- Dipartimento Farmaco-Chimico, University of Messina, Messina, Italy.
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31
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Manohar S, Khan SI, Rawat DS. Synthesis, antimalarial activity and cytotoxicity of 4-aminoquinoline–triazine conjugates. Bioorg Med Chem Lett 2010; 20:322-5. [DOI: 10.1016/j.bmcl.2009.10.106] [Citation(s) in RCA: 65] [Impact Index Per Article: 4.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/29/2009] [Revised: 10/01/2009] [Accepted: 10/26/2009] [Indexed: 10/20/2022]
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32
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Bellemare MJ, Bohle DS, Brosseau CN, Georges E, Godbout M, Kelly J, Leimanis ML, Leonelli R, Olivier M, Smilkstein M. Autofluorescence of condensed heme aggregates in malaria pigment and its synthetic equivalent hematin anhydride (beta-hematin). J Phys Chem B 2009; 113:8391-401. [PMID: 19472980 DOI: 10.1021/jp8104375] [Citation(s) in RCA: 19] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/24/2023]
Abstract
The condensed crystalline phase of iron(III) protoporphyrin IX either isolated from parasite culture as malaria pigment (hemozoin) or synthetic equivalent hematin anhydride exhibits a solid-state autofluorescence characterized by an excitation maximum of 555 nm and an emission maximum of 577 nm. The excitation spectrum maximum at 555 nm corresponds to the Q(0,0) band in the absorption spectrum which represents the lowest singlet of the material. This suggests that the fluorescent emission is due to the heme condensed phase. The photoluminescence lifetime of tau(f) = 2.7 +/- 0.8 ns as measured at four wavelengths between 550 and 600 nm is in the range of Frankel exciton in porphyrinic condensed phases. The material is shown to have an optical band gap of 2.04 eV characteristic of a semiconductor. Luminescence is markedly dependent upon the degree of hydration and the emission does not seem to be caused by presence of zinc(II) protoporphyrin IX or free-base protoporphyrin IX in the lattice. The autofluorescence can be used for in vivo tracking of hemozoin, for determination of parasitemia levels, and for infection monitoring and possibly for drug screening studies.
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Affiliation(s)
- Marie-Josée Bellemare
- Department of Chemistry, McGill University, 801 Sherbrooke Street West, Montreal, Quebec, Canada H3A 2K6
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33
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34
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Webster GT, McNaughton D, Wood BR. Aggregated Enhanced Raman Scattering in Fe(III)PPIX Solutions: The Effects of Concentration and Chloroquine on Excitonic Interactions. J Phys Chem B 2009; 113:6910-6. [DOI: 10.1021/jp811028a] [Citation(s) in RCA: 23] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Affiliation(s)
- Grant T. Webster
- Centre for Biospectroscopy and School of Chemistry, Monash University, Clayton, Victoria 3800, Australia
| | - Don McNaughton
- Centre for Biospectroscopy and School of Chemistry, Monash University, Clayton, Victoria 3800, Australia
| | - Bayden R. Wood
- Centre for Biospectroscopy and School of Chemistry, Monash University, Clayton, Victoria 3800, Australia
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35
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Frosch T, Koncarevic S, Becker K, Popp J. Morphology-sensitive Raman modes of the malaria pigment hemozoin. Analyst 2009; 134:1126-32. [DOI: 10.1039/b821705j] [Citation(s) in RCA: 42] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
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36
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Weissbuch I, Leiserowitz L. Interplay Between Malaria, Crystalline Hemozoin Formation, and Antimalarial Drug Action and Design. Chem Rev 2008; 108:4899-914. [DOI: 10.1021/cr078274t] [Citation(s) in RCA: 140] [Impact Index Per Article: 8.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Affiliation(s)
- Isabelle Weissbuch
- Department of Materials and Interfaces, The Weizmann Institute of Science, 76100-Rehovot, Israel
| | - Leslie Leiserowitz
- Department of Materials and Interfaces, The Weizmann Institute of Science, 76100-Rehovot, Israel
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Schlitzer M. Antimalarial drugs - what is in use and what is in the pipeline. Arch Pharm (Weinheim) 2008; 341:149-63. [PMID: 18297679 DOI: 10.1002/ardp.200700184] [Citation(s) in RCA: 99] [Impact Index Per Article: 6.2] [Reference Citation Analysis] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/09/2022]
Abstract
Malaria continues to be a potentially fatal threat to almost half of the world's population. In light of this threat, the armory to fight this disease is rather limited. Resistance against the most common and affordable antimalarials is widespread. Only few new drugs are in clinical development, most of them belong to long used classes of antimalarial drugs. This review will concisely cover the drugs which are currently in use, and describe the drug candidates which are in clinical evaluation.
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Affiliation(s)
- Martin Schlitzer
- Philipps-Universität, Institut für Pharmazeutische Chemie, Marburg, Germany.
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Sahu NK, Sahu S, Kohli DV. Novel Molecular Targets for Antimalarial Drug Development. Chem Biol Drug Des 2008; 71:287-97. [DOI: 10.1111/j.1747-0285.2008.00640.x] [Citation(s) in RCA: 27] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
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Abstract
A series of [(aryl)arylsufanylmethyl]pyridines (AASMP) have been synthesized. These compounds inhibited hemozoin formation, formed complexes (K(D) = 12 to 20 muM) with free heme (ferriprotoporphyrin IX) at a pH close to the pH of the parasite food vacuole, and exhibited antimalarial activity in vitro. The inhibition of hemozoin formation may develop oxidative stress in Plasmodium falciparum due to the accumulation of free heme. Interestingly, AASMP developed oxidative stress in the parasite, as evident from the decreased level of glutathione and increased formation of lipid peroxide, H(2)O(2), and hydroxyl radical (.OH) in P. falciparum. AASMP also caused mitochondrial dysfunction by decreasing mitochondrial potential (DeltaPsim) in malaria parasite, as measured by both flow cytometry and fluorescence microscopy. Furthermore, the generation of .OH may be mainly responsible for the antimalarial effect of AASMP since .OH scavengers such as mannitol, as well as spin trap alpha-phenyl-n-tertbutylnitrone, significantly protected P. falciparum from AASMP-mediated growth inhibition. Cytotoxicity testing of the active compounds showed selective activity against malaria parasite with selectivity indices greater than 100. AASMP also exhibited profound antimalarial activity in vivo against chloroquine resistant P. yoelii. Thus, AASMP represents a novel class of antimalarial.
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Ersmark K, Samuelsson B, Hallberg A. Plasmepsins as potential targets for new antimalarial therapy. Med Res Rev 2007; 26:626-66. [PMID: 16838300 DOI: 10.1002/med.20082] [Citation(s) in RCA: 122] [Impact Index Per Article: 7.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/12/2022]
Abstract
Malaria is one of the major diseases in the world. Due to the rapid spread of parasite resistance to available antimalarial drugs there is an urgent need for new antimalarials with novel mechanisms of action. Several promising targets for drug intervention have been revealed in recent years. This review addresses the parasitic aspartic proteases termed plasmepsins (Plms) that are involved in the hemoglobin catabolism that occurs during the erythrocytic stage of the malarial parasite life cycle. Four Plasmodium species are responsible for human malaria; P. vivax, P. ovale, P. malariae, and P. falciparum. This review focuses on inhibitors of the haemoglobin-degrading plasmepsins of the most lethal species, P. falciparum; Plm I, Plm II, Plm IV, and histo-aspartic protease (HAP). Previously, Plm II has attracted the most attention. With the identification and characterization of new plasmepsins and the results from recent plasmepsin knockout studies, it now seems clear that in order to achieve high-antiparasitic activities in P. falciparum-infected erythrocytes it is necessary to inhibit several of the haemoglobin-degrading plasmepsins. Herein we summarize the structure-activity relationships of the Plm I, II, IV, and HAP inhibitors. These inhibitors represent all classes which, to the best of our knowledge, have been disclosed in journal articles to date. The 3D structures of inhibitor/plasmepsin II complexes available in the protein data bank are briefly discussed and compared.
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Affiliation(s)
- Karolina Ersmark
- Department of Medicinal Chemistry, Uppsala University, BMC, SE-751 23 Uppsala, Sweden
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Schlitzer M. Malaria Chemotherapeutics Part I: History of Antimalarial Drug Development, Currently Used Therapeutics, and Drugs in Clinical Development. ChemMedChem 2007; 2:944-86. [PMID: 17530725 DOI: 10.1002/cmdc.200600240] [Citation(s) in RCA: 179] [Impact Index Per Article: 10.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/07/2022]
Abstract
Since ancient times, humankind has had to struggle against the persistent onslaught of pathogenic microorganisms. Nowadays, malaria is still the most important infectious disease worldwide. Considerable success in gaining control over malaria was achieved in the 1950s and 60s through landscaping measures, vector control with the insecticide DDT, and the widespread administration of chloroquine, the most important antimalarial agent ever. In the late 1960s, the final victory over malaria was believed to be within reach. However, the parasites could not be eradicated because they developed resistance against the most widely used and affordable drugs of that time. Today, cases of malaria infections are on the rise and have reached record numbers. This review gives a short description of the malaria disease, briefly addresses the history of antimalarial drug development, and focuses on drugs currently available for malaria therapy. The present knowledge regarding their mode of action and the mechanisms of resistance are explained, as are the attempts made by numerous research groups to overcome the resistance problem within classes of existing drugs and in some novel classes. Finally, this review covers all classes of antimalarials for which at least one drug candidate is in clinical development. Antimalarial agents that are solely in early development stages will be addressed in a separate review.
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Affiliation(s)
- Martin Schlitzer
- Institut für Pharmazeutische Chemie, Philipps-Universität Marburg, Marbacher Weg 6, 35032 Marburg, Germany.
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Chemaly SM, Chen CT, van Zyl RL. Naturally occurring cobalamins have antimalarial activity. J Inorg Biochem 2007; 101:764-73. [PMID: 17343914 DOI: 10.1016/j.jinorgbio.2007.01.006] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/20/2006] [Revised: 12/14/2006] [Accepted: 01/11/2007] [Indexed: 10/23/2022]
Abstract
The acquisition of resistance by malaria parasites towards existing antimalarials has necessitated the development of new chemotherapeutic agents. The effect of vitamin B(12) derivatives on the formation of beta-haematin (synthetic haemozoin) was determined under conditions similar to those in the parasitic food vacuole (using chloroquine, a known inhibitor of haemozoin formation for comparison). Adenosylcobalamin (Ado-cbl), methylcobalamin (CH(3)-cbl) and aquocobalamin (H(2)O-cbl) were approximately forty times more effective inhibitors of beta-haematin formation than chloroquine, cyanocobalamin (CN-cbl) was slightly more inhibitory than chloroquine, while dicyanocobinamide had no effect. It is proposed that the cobalamins exert their inhibitory effect on beta-haematin formation by pi-interactions of their corrin ring with the Fe(III)-protoporphyrin ring and by hydrogen-bonding using their 5,6-dimethylbenzimidazole/ribose/sugar side-chain. The antimalarial activity for the cobalamins (Ado-cbl>CH(3)-cbl>H(2)O-cbl>CN-cbl) was found to be less than that for chloroquine or quinine. Ado-cbl, CH(3)-cbl and CN-cbl do not accumulate in the parasite food vacuole by pH trapping, but H(2)O-cbl does. Unlike humans, the malaria parasite has only one enzyme that uses cobalamin as a cofactor, namely methionine synthase, which is important for growth and metabolism. Thus cobalamins in very small amounts are necessary for Plasmodium falciparum growth but in larger amounts they display antimalarial properties.
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Affiliation(s)
- Susan M Chemaly
- Department of Pharmacy and Pharmacology, Faculty of Health Sciences, University of the Witwatersrand, Johannesburg, South Africa.
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Kumar S, Guha M, Choubey V, Maity P, Bandyopadhyay U. Antimalarial drugs inhibiting hemozoin (β-hematin) formation: A mechanistic update. Life Sci 2007; 80:813-28. [PMID: 17157328 DOI: 10.1016/j.lfs.2006.11.008] [Citation(s) in RCA: 111] [Impact Index Per Article: 6.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/22/2006] [Revised: 10/24/2006] [Accepted: 11/06/2006] [Indexed: 11/30/2022]
Abstract
Digestion of hemoglobin in the food vacuole of the malaria parasite produces very high quantities of redox active toxic free heme. Hemozoin (beta-hematin) formation is a unique process adopted by Plasmodium sp. to detoxify free heme. Hemozoin formation is a validated target for most of the well-known existing antimalarial drugs and considered to be a suitable target to develop new antimalarials. Here we discuss the possible mechanisms of free heme detoxification in the malaria parasite and the mechanistic details of compounds, which offer antimalarial activity by inhibiting hemozoin formation. The chemical nature of new antimalarial compounds showing antimalarial activity through the inhibition of hemozoin formation has also been incorporated, which may help to design future antimalarials with therapeutic potential against multi-drug resistant malaria.
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Affiliation(s)
- Sanjay Kumar
- Division of Drug Target Discovery and Development, Central Drug Research Institute, Chatter Manzil Palace, Mahatma Gandhi Marg, Lucknow-226001, Uttar Pradesh, India
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Mbewe B, Chibale K, McIntosh DB. Purification of human malaria parasite hypoxanthine guanine xanthine phosphoribosyltransferase (HGXPRT) using immobilized Reactive Red 120. Protein Expr Purif 2006; 52:153-8. [PMID: 17097304 DOI: 10.1016/j.pep.2006.09.014] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/29/2006] [Revised: 09/15/2006] [Accepted: 09/26/2006] [Indexed: 11/17/2022]
Abstract
Malaria is caused by Plasmodium parasite infection. The human malarial parasite does not have a de novo pathway for synthesis of nucleotides and the purine salvage pathway enzyme hypoxanthine guanine xanthine phosphoribosyltransferase (HGXPRT) is critical for survival. In our efforts to find inhibitors of the malarial parasite HGXPRT, we have developed a simple but effective purification protocol for this protein expressed in Escherichia coli without an affinity tag. The protocol consists of tandem columns of anion exchange and immobilized Reactive Red 120 resins. The enzyme is inactive as isolated but can be activated by incubation with substrate(s).
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Affiliation(s)
- Boniface Mbewe
- Chemistry Department, School of Natural Sciences, University of Zambia, P.O. Box 32379 , Lusaka, Zambia.
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Skórska A, Sliwiński J, Oleksyn BJ. Conformation stability and organization of mefloquine molecules in different environments. Bioorg Med Chem Lett 2006; 16:850-3. [PMID: 16303303 DOI: 10.1016/j.bmcl.2005.11.016] [Citation(s) in RCA: 17] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/02/2005] [Revised: 11/04/2005] [Accepted: 11/04/2005] [Indexed: 11/28/2022]
Abstract
The crystal structures of mefloquine base, [C17H16F6N2O], and two salts of mefloquine: hydrochloride [(C17H17F6N2O)+]3[Cl-]3.3H2O and hydrochloride tetrachlorocobaltate [(C17H17F6N2O)+]3Cl-[CoCl4]2-.C2H6O.H2O, were determined by X-ray diffraction measurements. A comparison of the crystal structures of mefloquine in three different crystalline environments shows that their conformations are stable regardless of mefloquine being a base or a salt. In addition, the conformation of mefloquine is similar to those of crystalline Cinchona alkaloids. The CF3 substituents in the quinoline moiety affect the packing of molecules.
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Affiliation(s)
- Agnieszka Skórska
- Jagiellonian University, Faculty of Chemistry, Ingardena 3, 30-060 Kraków, Poland.
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Ncokazi KK, Egan TJ. A colorimetric high-throughput β-hematin inhibition screening assay for use in the search for antimalarial compounds. Anal Biochem 2005; 338:306-19. [PMID: 15745752 DOI: 10.1016/j.ab.2004.11.022] [Citation(s) in RCA: 146] [Impact Index Per Article: 7.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/28/2004] [Indexed: 10/26/2022]
Abstract
Antimalarial drugs such as chloroquine are believed to act by inhibiting hemozoin formation in the food vacuole of the malaria parasite. We have developed a new assay for measuring and detecting inhibition of synthetic hemozoin (beta-hematin) formation. Aqueous pyridine (5% v/v, pH 7.5) forms a low-spin complex with hematin but not with beta-hematin. Its absorbance obeys Beer's law, making it useful for quantitating hematin concentration in hematin/beta-hematin mixtures, allowing compounds to be investigated for inhibition of beta-hematin formation. The assay is rapid (60 min incubation) and requires no centrifugation. The beta-hematin inhibition data show good agreement with alternative assay methods reported by four laboratories. The assay was adapted for high-throughput colorimetric screening, allowing visual identification of beta-hematin inhibitors. In this mode, the assay successfully detected all 18 beta-hematin inhibitors in a set of 47 compounds tested, with no false positive results. The quantitative in vitro antimalarial activities of a set of 13 aminoquinolines and quinoline methanols were found to correlate significantly with beta-hematin inhibition values determined using the assay.
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Affiliation(s)
- Kanyile K Ncokazi
- Department of Chemistry, University of Cape Town, Private Bag, Rondebosch 7701, South Africa
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