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Schäfer TM, Pessanha de Carvalho L, Inoue J, Kreidenweiss A, Held J. The problem of antimalarial resistance and its implications for drug discovery. Expert Opin Drug Discov 2024; 19:209-224. [PMID: 38108082 DOI: 10.1080/17460441.2023.2284820] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/28/2023] [Accepted: 11/14/2023] [Indexed: 12/19/2023]
Abstract
INTRODUCTION Malaria remains a devastating infectious disease with hundreds of thousands of casualties each year. Antimalarial drug resistance has been a threat to malaria control and elimination for many decades and is still of concern today. Despite the continued effectiveness of current first-line treatments, namely artemisinin-based combination therapies, the emergence of drug-resistant parasites in Southeast Asia and even more alarmingly the occurrence of resistance mutations in Africa is of great concern and requires immediate attention. AREAS COVERED A comprehensive overview of the mechanisms underlying the acquisition of drug resistance in Plasmodium falciparum is given. Understanding these processes provides valuable insights that can be harnessed for the development and selection of novel antimalarials with reduced resistance potential. Additionally, strategies to mitigate resistance to antimalarial compounds on the short term by using approved drugs are discussed. EXPERT OPINION While employing strategies that utilize already approved drugs may offer a prompt and cost-effective approach to counter antimalarial drug resistance, it is crucial to recognize that only continuous efforts into the development of novel antimalarial drugs can ensure the successful treatment of malaria in the future. Incorporating resistance propensity assessment during this developmental process will increase the likelihood of effective and enduring malaria treatments.
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Affiliation(s)
| | | | - Juliana Inoue
- Institute of Tropical Medicine, University of Tübingen, Tübingen, Germany
| | - Andrea Kreidenweiss
- Institute of Tropical Medicine, University of Tübingen, Tübingen, Germany
- Centre de Recherches Médicales de Lambaréné, Lambaréné, Gabon
- German Center for Infection Research (DZIF), Tübingen, Germany
| | - Jana Held
- Institute of Tropical Medicine, University of Tübingen, Tübingen, Germany
- Centre de Recherches Médicales de Lambaréné, Lambaréné, Gabon
- German Center for Infection Research (DZIF), Tübingen, Germany
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2
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Kumar S, Kapkoti DS, Mina PR, Gupta M, Kumar R, Kumar P, Pathak P, Bhakuni RS, Rout P, Pal A, Darokar MP. Effect of liquiritigenin on chloroquine accumulation in digestive vacuole leading to apoptosis-like death of chloroquine-resistant P. falciparum. PHYTOMEDICINE : INTERNATIONAL JOURNAL OF PHYTOTHERAPY AND PHYTOPHARMACOLOGY 2023; 114:154738. [PMID: 36940579 DOI: 10.1016/j.phymed.2023.154738] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/30/2022] [Revised: 02/23/2023] [Accepted: 02/28/2023] [Indexed: 06/18/2023]
Abstract
BACKGROUND Malaria remains one of the major health concerns, especially in tropical countries. Although drugs such as artemisinin-based combinations are efficient for treating Plasmodium falciparum, the growing threat from multi-drug resistance has become a major challenge. Thus, there is a constant need to identify and validate new combinations to sustain current disease control strategies to overcome the challenge of drug resistance in the malaria parasites. To meet this demand, liquiritigenin (LTG) has been found to positively interact in combination with the existing clinically used drug chloroquine (CQ), which has become unfunctional due to acquired drug resistance. PURPOSE To evaluate the best interaction between LTG and CQ against CQ- resistant strain of P. falciparum. Furthermore, the in vivo antimalarial efficacy and possible mechanism of action of the best combination was also assessed. METHODS The in vitro anti-plasmodial potential of LTG against CQ- resistant strain K1 of P. falciparum was tested using Giemsa staining method. The behaviour of the combinations was evaluated using the fix ratio method and evaluated the interaction of LTG and CQ by calculating the fractional inhibitory concentration index (FICI). Oral toxicity study was carried out in a mice model. In vivo antimalarial efficacy of LTG alone and in combination with CQ was evaluated using a four-day suppression test in a mouse model. The effect of LTG on CQ accumulation was measured using HPLC and the rate of alkalinization of the digestive vacuole. Cytosolic Ca2+ level, mitochondrial membrane potential, caspase-like activity, terminal deoxynucleotidyl transferase dUTP nick end labeling (TUNEL) assay, and Annexin V Apoptosis assay to assess anti-plasmodial potential. Proteomics analysis was evaluated by LC-MS/MS analysis. RESULTS LTG possesses anti-plasmodial activity on its own and it showed to be an adjuvant of CQ. In in vitro studies, LTG showed synergy with CQ only in the ratio (CQ: LTG-1:4) against CQ-resistant strain (K1) of P. falciparum. Interestingly, in vivo studies, LTG in combination with CQ showed higher chemo-suppression and enhanced mean survival time at much lower concentrations compared to individual doses of LTG and CQ against CQ- resistant strain (N67) of Plasmodium yoelli nigeriensis. LTG was found to increase the CQ accumulation into digestive vacuole, reducing the rate of alkalinization, in turn increasing cytosolic Ca2+ level, loss of mitochondrial potential, caspase-3 activity, DNA damage and externalization of phosphatidylserine of the membrane (in vitro). These observations indicate the involvement of apoptosis-like death of P. falciparum that might be due to the accumulation of CQ. CONCLUSION LTG showed synergy with CQ in the ratio LTG: CQ, 4:1) in vitro and was able to curtail the IC50 of CQ and LTG. Interestingly, in vivo in combination with CQ, LTG showed higher chemo-suppression as well as enhanced mean survival time at a much lower concentrations of both the partners as compared to an individual dose of CQ and LTG. Thus, synergistic drug combination offers the possibility to enhance CQ efficacy in chemotherapy.
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Affiliation(s)
- Saurabh Kumar
- Bioprospection and Product Development Division, CSIR- Central Institute of Medicinal and Aromatic Plants, Lucknow, India
| | - Deepak Singh Kapkoti
- Phytochemistry Division, CSIR-Central Institute of Medicinal and Aromatic Plants, Lucknow, India
| | - Pooja Rani Mina
- Bioprospection and Product Development Division, CSIR- Central Institute of Medicinal and Aromatic Plants, Lucknow, India
| | - Madhuri Gupta
- Phytochemistry Division, CSIR-Central Institute of Medicinal and Aromatic Plants, Lucknow, India
| | - Ravi Kumar
- Bioprospection and Product Development Division, CSIR- Central Institute of Medicinal and Aromatic Plants, Lucknow, India
| | - Parmanand Kumar
- Bioprospection and Product Development Division, CSIR- Central Institute of Medicinal and Aromatic Plants, Lucknow, India
| | - Priyanka Pathak
- Bioprospection and Product Development Division, CSIR- Central Institute of Medicinal and Aromatic Plants, Lucknow, India
| | - R S Bhakuni
- Phytochemistry Division, CSIR-Central Institute of Medicinal and Aromatic Plants, Lucknow, India
| | - Prasant Rout
- Phytochemistry Division, CSIR-Central Institute of Medicinal and Aromatic Plants, Lucknow, India
| | - Anirban Pal
- Bioprospection and Product Development Division, CSIR- Central Institute of Medicinal and Aromatic Plants, Lucknow, India.
| | - Mahendra P Darokar
- Bioprospection and Product Development Division, CSIR- Central Institute of Medicinal and Aromatic Plants, Lucknow, India.
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3
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Sanchez CP, Manson EDT, Moliner Cubel S, Mandel L, Weidt SK, Barrett MP, Lanzer M. The Knock-Down of the Chloroquine Resistance Transporter PfCRT Is Linked to Oligopeptide Handling in Plasmodium falciparum. Microbiol Spectr 2022; 10:e0110122. [PMID: 35867395 PMCID: PMC9431119 DOI: 10.1128/spectrum.01101-22] [Citation(s) in RCA: 8] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/26/2022] [Accepted: 06/27/2022] [Indexed: 11/20/2022] Open
Abstract
The chloroquine resistance transporter, PfCRT, is an essential factor during intraerythrocytic development of the human malaria parasite Plasmodium falciparum. PfCRT resides at the digestive vacuole of the parasite, where hemoglobin taken up by the parasite from its host cell is degraded. PfCRT can acquire several mutations that render PfCRT a drug transporting system expelling compounds targeting hemoglobin degradation from the digestive vacuole. The non-drug related function of PfCRT is less clear, although a recent study has suggested a role in oligopeptide transport based on studies conducted in a heterologous expression system. The uncertainty about the natural function of PfCRT is partly due to a lack of a null mutant and a dearth of functional assays in the parasite. Here, we report on the generation of a conditional PfCRT knock-down mutant in P. falciparum. The mutant accumulated oligopeptides 2 to at least 8 residues in length under knock-down conditions, as shown by comparative global metabolomics. The accumulated oligopeptides were structurally diverse, had an isoelectric point between 4.0 and 5.4 and were electrically neutral or carried a single charge at the digestive vacuolar pH of 5.2. Fluorescently labeled dipeptides and live cell imaging identified the digestive vacuole as the compartment where oligopeptides accumulated. Our findings suggest a function of PfCRT in oligopeptide transport across the digestive vacuolar membrane in P. falciparum and associated with it a role in nutrient acquisition and the maintenance of the colloid osmotic balance. IMPORTANCE The chloroquine resistance transporter, PfCRT, is important for the survival of the human malaria parasite Plasmodium falciparum. It increases the tolerance to many antimalarial drugs, and it is essential for the development of the parasite within red blood cells. While we understand the role of PfCRT in drug resistance in ever increasing detail, the non-drug resistance functions are still debated. Identifying the natural substrate of PfCRT has been hampered by a paucity of functional assays to test putative substrates in the parasite system and the absence of a parasite mutant deficient for the PfCRT encoding gene. By generating a conditional PfCRT knock-down mutant, together with comparative metabolomics and uptake studies using fluorescently labeled oligopeptides, we could show that PfCRT is an oligopeptide transporter. The oligopeptides were structurally diverse and were electrically neutral or carried a single charge. Our data support a function of PfCRT in oligopeptide transport.
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Affiliation(s)
- Cecilia P. Sanchez
- Center of Infectious Diseases, Parasitology, Universitätsklinikum Heidelberg, Heidelberg, Germany
| | | | - Sonia Moliner Cubel
- Center of Infectious Diseases, Parasitology, Universitätsklinikum Heidelberg, Heidelberg, Germany
| | | | - Stefan K. Weidt
- Glasgow Polyomics, University of Glasgow, Wolfson Wohl Cancer Research Centre, Glasgow, United Kingdom
| | - Michael P. Barrett
- Glasgow Polyomics, University of Glasgow, Wolfson Wohl Cancer Research Centre, Glasgow, United Kingdom
- The Wellcome Centre for Integrative Parasitology, Institute for Infection, Immunity and Inflammation, College of Medical, Veterinary and Life Sciences, University of Glasgow, Glasgow, United Kingdom
| | - Michael Lanzer
- Center of Infectious Diseases, Parasitology, Universitätsklinikum Heidelberg, Heidelberg, Germany
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Mechanistic basis for multidrug resistance and collateral drug sensitivity conferred to the malaria parasite by polymorphisms in PfMDR1 and PfCRT. PLoS Biol 2022; 20:e3001616. [PMID: 35507548 PMCID: PMC9067703 DOI: 10.1371/journal.pbio.3001616] [Citation(s) in RCA: 12] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/23/2021] [Accepted: 03/31/2022] [Indexed: 01/16/2023] Open
Abstract
Polymorphisms in the Plasmodium falciparum multidrug resistance protein 1 (pfmdr1) gene and the Plasmodium falciparum chloroquine resistance transporter (pfcrt) gene alter the malaria parasite’s susceptibility to most of the current antimalarial drugs. However, the precise mechanisms by which PfMDR1 contributes to multidrug resistance have not yet been fully elucidated, nor is it understood why polymorphisms in pfmdr1 and pfcrt that cause chloroquine resistance simultaneously increase the parasite’s susceptibility to lumefantrine and mefloquine—a phenomenon known as collateral drug sensitivity. Here, we present a robust expression system for PfMDR1 in Xenopus oocytes that enables direct and high-resolution biochemical characterizations of the protein. We show that wild-type PfMDR1 transports diverse pharmacons, including lumefantrine, mefloquine, dihydroartemisinin, piperaquine, amodiaquine, methylene blue, and chloroquine (but not the antiviral drug amantadine). Field-derived mutant isoforms of PfMDR1 differ from the wild-type protein, and each other, in their capacities to transport these drugs, indicating that PfMDR1-induced changes in the distribution of drugs between the parasite’s digestive vacuole (DV) and the cytosol are a key driver of both antimalarial resistance and the variability between multidrug resistance phenotypes. Of note, the PfMDR1 isoforms prevalent in chloroquine-resistant isolates exhibit reduced capacities for chloroquine, lumefantrine, and mefloquine transport. We observe the opposite relationship between chloroquine resistance-conferring mutations in PfCRT and drug transport activity. Using our established assays for characterizing PfCRT in the Xenopus oocyte system and in live parasite assays, we demonstrate that these PfCRT isoforms transport all 3 drugs, whereas wild-type PfCRT does not. We present a mechanistic model for collateral drug sensitivity in which mutant isoforms of PfMDR1 and PfCRT cause chloroquine, lumefantrine, and mefloquine to remain in the cytosol instead of sequestering within the DV. This change in drug distribution increases the access of lumefantrine and mefloquine to their primary targets (thought to be located outside of the DV), while simultaneously decreasing chloroquine’s access to its target within the DV. The mechanistic insights presented here provide a basis for developing approaches that extend the useful life span of antimalarials by exploiting the opposing selection forces they exert upon PfCRT and PfMDR1.
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5
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Nudelman A. Dimeric Drugs. Curr Med Chem 2021; 29:2751-2845. [PMID: 34375175 DOI: 10.2174/0929867328666210810124159] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/18/2021] [Revised: 06/18/2021] [Accepted: 06/29/2021] [Indexed: 11/22/2022]
Abstract
This review intends to summarize the structures of an extensive number of symmetrical-dimeric drugs, having two monomers linked via a bridging entity while emphasizing the large versatility of biologically active substances reported to possess dimeric structures. The largest number of classes of these compounds consist of anticancer agents, antibiotics/antimicrobials, and anti-AIDS drugs. Other symmetrical-dimeric drugs include antidiabetics, antidepressants, analgesics, anti-inflammatories, drugs for the treatment of Alzheimer's disease, anticholesterolemics, estrogenics, antioxidants, enzyme inhibitors, anti-Parkisonians, laxatives, antiallergy compounds, cannabinoids, etc. Most of the articles reviewed do not compare the activity/potency of the dimers to that of their corresponding monomers. Only in limited cases, various suggestions have been made to justify unexpected higher activity of the dimers vs. the corresponding monomers. These suggestions include statistical effects, the presence of dimeric receptors, binding of a dimer to two receptors simultaneously, and others. It is virtually impossible to predict which dimers will be preferable to their respective monomers, or which linking bridges will lead to the most active compounds. It is expected that the extensive number of articles summarized, and the large variety of substances mentioned, which display various biological activities, should be of interest to many academic and industrial medicinal chemists.
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Affiliation(s)
- Abraham Nudelman
- Chemistry Department, Bar Ilan University, Ramat Gan 52900, Israel
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6
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Relitti N, Federico S, Pozzetti L, Butini S, Lamponi S, Taramelli D, D'Alessandro S, Martin RE, Shafik SH, Summers RL, Babij SK, Habluetzel A, Tapanelli S, Caldelari R, Gemma S, Campiani G. Synthesis and biological evaluation of benzhydryl-based antiplasmodial agents possessing Plasmodium falciparum chloroquine resistance transporter (PfCRT) inhibitory activity. Eur J Med Chem 2021; 215:113227. [PMID: 33601312 DOI: 10.1016/j.ejmech.2021.113227] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/16/2020] [Revised: 01/21/2021] [Accepted: 01/21/2021] [Indexed: 11/18/2022]
Abstract
Due to the surge in resistance to common therapies, malaria remains a significant concern to human health worldwide. In chloroquine (CQ)-resistant (CQ-R) strains of Plasmodium falciparum, CQ and related drugs are effluxed from the parasite's digestive vacuole (DV). This process is mediated by mutant isoforms of a protein called CQ resistance transporter (PfCRT). CQ-R strains can be partially re-sensitized to CQ by verapamil (VP), primaquine (PQ) and other compounds, and this has been shown to be due to the ability of these molecules to inhibit drug transport via PfCRT. We have previously developed a series of clotrimazole (CLT)-based antimalarial agents that possess inhibitory activity against PfCRT (4a,b). In our endeavor to develop novel PfCRT inhibitors, and to perform a structure-activity relationship analysis, we synthesized a new library of analogues. When the benzhydryl system was linked to a 4-aminoquinoline group (5a-f) the resulting compounds exhibited good cytotoxicity against both CQ-R and CQ-S strains of P. falciparum. The most potent inhibitory activity against the PfCRT-mediated transport of CQ was obtained with compound 5k. When compared to the reference compound, benzhydryl analogues of PQ (5i,j) showed a similar activity against blood-stage parasites, and a stronger in vitro potency against liver-stage parasites. Unfortunately, in the in vivo transmission blocking assays, 5i,j were inactive against gametocytes.
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Affiliation(s)
- Nicola Relitti
- Department of Biotechnology, Chemistry and Pharmacy (DoE 2018-2022), University of Siena, Via Aldo Moro 2, 53100 Siena, Italy; Centro Interuniversitario di Ricerche Sulla Malaria (CIRM), University of Milan, Milano, Italy
| | - Stefano Federico
- Department of Biotechnology, Chemistry and Pharmacy (DoE 2018-2022), University of Siena, Via Aldo Moro 2, 53100 Siena, Italy; Centro Interuniversitario di Ricerche Sulla Malaria (CIRM), University of Milan, Milano, Italy
| | - Luca Pozzetti
- Department of Biotechnology, Chemistry and Pharmacy (DoE 2018-2022), University of Siena, Via Aldo Moro 2, 53100 Siena, Italy; Centro Interuniversitario di Ricerche Sulla Malaria (CIRM), University of Milan, Milano, Italy
| | - Stefania Butini
- Department of Biotechnology, Chemistry and Pharmacy (DoE 2018-2022), University of Siena, Via Aldo Moro 2, 53100 Siena, Italy; Centro Interuniversitario di Ricerche Sulla Malaria (CIRM), University of Milan, Milano, Italy
| | - Stefania Lamponi
- Department of Biotechnology, Chemistry and Pharmacy (DoE 2018-2022), University of Siena, Via Aldo Moro 2, 53100 Siena, Italy; Centro Interuniversitario di Ricerche Sulla Malaria (CIRM), University of Milan, Milano, Italy
| | - Donatella Taramelli
- Department of Pharmacological and Biomolecular Sciences, University of Milan, Via Pascal 36, 20133, Milan, Italy; Centro Interuniversitario di Ricerche Sulla Malaria (CIRM), University of Milan, Milano, Italy
| | - Sarah D'Alessandro
- Department of Biomedical, Surgical and Dental Sciences, University of Milan, Via Pascal 36, 20133, Milan, Italy; Centro Interuniversitario di Ricerche Sulla Malaria (CIRM), University of Milan, Milano, Italy
| | - Rowena E Martin
- Research School of Biology, Australian National University, Canberra, ACT, 2600, Australia
| | - Sarah H Shafik
- Research School of Biology, Australian National University, Canberra, ACT, 2600, Australia
| | - Robert L Summers
- Research School of Biology, Australian National University, Canberra, ACT, 2600, Australia
| | - Simone K Babij
- Research School of Biology, Australian National University, Canberra, ACT, 2600, Australia
| | - Annette Habluetzel
- School of Pharmacy, University of Camerino, Piazza Cavour 19F, 62032, Camerino, Italy; Centro Interuniversitario di Ricerche Sulla Malaria (CIRM), University of Milan, Milano, Italy
| | - Sofia Tapanelli
- School of Pharmacy, University of Camerino, Piazza Cavour 19F, 62032, Camerino, Italy; Centro Interuniversitario di Ricerche Sulla Malaria (CIRM), University of Milan, Milano, Italy
| | - Reto Caldelari
- Institute of Cell Biology, University of Bern, Baltzerstrasse 4, 3012, Bern, Switzerland
| | - Sandra Gemma
- Department of Biotechnology, Chemistry and Pharmacy (DoE 2018-2022), University of Siena, Via Aldo Moro 2, 53100 Siena, Italy; Centro Interuniversitario di Ricerche Sulla Malaria (CIRM), University of Milan, Milano, Italy.
| | - Giuseppe Campiani
- Department of Biotechnology, Chemistry and Pharmacy (DoE 2018-2022), University of Siena, Via Aldo Moro 2, 53100 Siena, Italy; Centro Interuniversitario di Ricerche Sulla Malaria (CIRM), University of Milan, Milano, Italy
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7
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Che ZP, Yang JM, Zhang S, Sun D, Tian YE, Liu SM, Lin XM, Jiang J, Chen GQ. Synthesis of novel 9 R/S-acyloxy derivatives of cinchonidine and cinchonine as insecticidal agents. JOURNAL OF ASIAN NATURAL PRODUCTS RESEARCH 2021; 23:163-175. [PMID: 32091234 DOI: 10.1080/10286020.2020.1729136] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/22/2019] [Revised: 01/30/2020] [Accepted: 02/09/2020] [Indexed: 06/10/2023]
Abstract
Endeavor to discover biorational natural products-based insecticides, two series (27) of novel 9R/S-acyloxy derivatives of cinchonidine and cinchonine were prepared and assessed for their insecticidal activity against Mythimna separata in vivo by the leaf-dipping method at 1 mg/mL. Among all the compounds, especially derivatives 6l and 6o exhibited the best insecticidal activity with final mortality rates of 75.0% and 71.4%, respectively. Overall, a free 9-hydroxyl group is not a prerequisite for insecticidal activity and C9-substitution is well tolerated; the configuration of C8/9 position is important for insecticidal activity, and 9S-configuration is optimal; 6'-OCH3 moiety is not necessary, removal of it is also acceptable. [Formula: see text].
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Affiliation(s)
- Zhi-Ping Che
- Laboratory of Pesticidal Design & Synthesis, Department of Plant Protection, College of Forestry, Henan University of Science and Technology, Luoyang 471023, China
| | - Jin-Ming Yang
- Laboratory of Pesticidal Design & Synthesis, Department of Plant Protection, College of Forestry, Henan University of Science and Technology, Luoyang 471023, China
| | - Song Zhang
- Laboratory of Pesticidal Design & Synthesis, Department of Plant Protection, College of Forestry, Henan University of Science and Technology, Luoyang 471023, China
| | - Di Sun
- Laboratory of Pesticidal Design & Synthesis, Department of Plant Protection, College of Forestry, Henan University of Science and Technology, Luoyang 471023, China
| | - Yue-E Tian
- Laboratory of Pesticidal Design & Synthesis, Department of Plant Protection, College of Forestry, Henan University of Science and Technology, Luoyang 471023, China
| | - Sheng-Ming Liu
- Laboratory of Pesticidal Design & Synthesis, Department of Plant Protection, College of Forestry, Henan University of Science and Technology, Luoyang 471023, China
| | - Xiao-Min Lin
- Laboratory of Pesticidal Design & Synthesis, Department of Plant Protection, College of Forestry, Henan University of Science and Technology, Luoyang 471023, China
| | - Jia Jiang
- Laboratory of Pesticidal Design & Synthesis, Department of Plant Protection, College of Forestry, Henan University of Science and Technology, Luoyang 471023, China
| | - Gen-Qiang Chen
- Laboratory of Pesticidal Design & Synthesis, Department of Plant Protection, College of Forestry, Henan University of Science and Technology, Luoyang 471023, China
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8
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Shafik SH, Cobbold SA, Barkat K, Richards SN, Lancaster NS, Llinás M, Hogg SJ, Summers RL, McConville MJ, Martin RE. The natural function of the malaria parasite's chloroquine resistance transporter. Nat Commun 2020; 11:3922. [PMID: 32764664 PMCID: PMC7413254 DOI: 10.1038/s41467-020-17781-6] [Citation(s) in RCA: 42] [Impact Index Per Article: 10.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/07/2019] [Accepted: 07/15/2020] [Indexed: 01/27/2023] Open
Abstract
The Plasmodium falciparum chloroquine resistance transporter (PfCRT) is a key contributor to multidrug resistance and is also essential for the survival of the malaria parasite, yet its natural function remains unresolved. We identify host-derived peptides of 4-11 residues, varying in both charge and composition, as the substrates of PfCRT in vitro and in situ, and show that PfCRT does not mediate the non-specific transport of other metabolites and/or ions. We find that drug-resistance-conferring mutations reduce both the peptide transport capacity and substrate range of PfCRT, explaining the impaired fitness of drug-resistant parasites. Our results indicate that PfCRT transports peptides from the lumen of the parasite's digestive vacuole to the cytosol, thereby providing a source of amino acids for parasite metabolism and preventing osmotic stress of this organelle. The resolution of PfCRT's native substrates will aid the development of drugs that target PfCRT and/or restore the efficacy of existing antimalarials.
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Affiliation(s)
- Sarah H Shafik
- Research School of Biology, The Australian National University, Canberra, ACT, 2601, Australia
| | - Simon A Cobbold
- Bio21 Molecular Science and Biotechnology Institute, University of Melbourne, Melbourne, VIC, 3052, Australia
| | - Kawthar Barkat
- Research School of Biology, The Australian National University, Canberra, ACT, 2601, Australia
| | - Sashika N Richards
- Research School of Biology, The Australian National University, Canberra, ACT, 2601, Australia
| | - Nicole S Lancaster
- Research School of Biology, The Australian National University, Canberra, ACT, 2601, Australia
| | - Manuel Llinás
- Department of Biochemistry and Molecular Biology, Department of Chemistry, and Huck Center for Malaria Research, The Pennsylvania State University, University Park, PA, 16802, USA
| | - Simon J Hogg
- Research School of Biology, The Australian National University, Canberra, ACT, 2601, Australia
| | - Robert L Summers
- Research School of Biology, The Australian National University, Canberra, ACT, 2601, Australia
| | - Malcolm J McConville
- Bio21 Molecular Science and Biotechnology Institute, University of Melbourne, Melbourne, VIC, 3052, Australia
| | - Rowena E Martin
- Research School of Biology, The Australian National University, Canberra, ACT, 2601, Australia.
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9
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Che Z, Yang J, Sun D, Tian Y, Liu S, Lin X, Jiang J, Chen G. Synthesis of Novel (9
S
)‐Acyloxy Derivatives of Quinidine and Dihydroquinidine as Insecticidal Agents. Chem Biodivers 2020; 17:e1900696. [DOI: 10.1002/cbdv.201900696] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/03/2019] [Accepted: 03/05/2020] [Indexed: 01/17/2023]
Affiliation(s)
- Zhiping Che
- Laboratory of Pesticidal Design and SynthesisDepartment of Plant Protection, College of ForestryHenan University of Science and Technology Luoyang 471023 P. R. China
| | - Jinming Yang
- Laboratory of Pesticidal Design and SynthesisDepartment of Plant Protection, College of ForestryHenan University of Science and Technology Luoyang 471023 P. R. China
| | - Di Sun
- Laboratory of Pesticidal Design and SynthesisDepartment of Plant Protection, College of ForestryHenan University of Science and Technology Luoyang 471023 P. R. China
| | - Yuee Tian
- Laboratory of Pesticidal Design and SynthesisDepartment of Plant Protection, College of ForestryHenan University of Science and Technology Luoyang 471023 P. R. China
| | - Shengming Liu
- Laboratory of Pesticidal Design and SynthesisDepartment of Plant Protection, College of ForestryHenan University of Science and Technology Luoyang 471023 P. R. China
| | - Xiaomin Lin
- Laboratory of Pesticidal Design and SynthesisDepartment of Plant Protection, College of ForestryHenan University of Science and Technology Luoyang 471023 P. R. China
| | - Jia Jiang
- Laboratory of Pesticidal Design and SynthesisDepartment of Plant Protection, College of ForestryHenan University of Science and Technology Luoyang 471023 P. R. China
| | - Genqiang Chen
- Laboratory of Pesticidal Design and SynthesisDepartment of Plant Protection, College of ForestryHenan University of Science and Technology Luoyang 471023 P. R. China
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10
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Che Z, Yang J, Sun D, Tian Y, Liu S, Lin X, Jiang J, Chen G. Combinatorial Synthesis of Novel 9R-Acyloxyquinine Derivatives as Insecticidal Agents. Comb Chem High Throughput Screen 2020; 23:111-118. [PMID: 31958039 DOI: 10.2174/1386207323666200120112714] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/22/2019] [Revised: 12/30/2019] [Accepted: 01/01/2020] [Indexed: 11/22/2022]
Abstract
BACKGROUND It is one of the effective ways for pesticide innovation to develop new insecticides from natural products as lead compounds. Quinine, the main alkaloid in the bark of cinchona tree as well as in plants in the same genus, is recognized as a safe and potent botanical insecticide to many insects. The structural modification of quinine into 9R-acyloxyquinine derivatives is a potential approach for the development of novel insecticides, which showed more toxicity than quinine. However, there are no reports on the insecticidal activity of 9Racyloxyquinine derivatives to control Mythimna separata. METHODS Endeavor to discover biorational natural products-based insecticides, 20 novel 9Racyloxyquinine derivatives were prepared and assessed for their insecticidal activity against M. separata in vivo by the leaf-dipping method at 1 mg/mL. RESULTS Among all the compounds, especially derivatives 5i, 5k and 5t exhibited the best insecticidal activity with final mortality rates of 50.0%, 57.1%, and 53.6%, respectively. CONCLUSION Overall, a free 9-hydroxyl group is not a prerequisite for insecticidal activity and C9- substitution is well tolerated; modification of out-ring double-bond is acceptable, and hydrogenation of double-bond enhances insecticidal activity; Quinine ring is essential and open of it is not acceptable. These preliminary results will pave the way for further modification of quinine in the development of potential new insecticides.
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Affiliation(s)
- Zhiping Che
- Laboratory of Pesticidal Design and Synthesis, Department of Plant Protection, College of Forestry, Henan University of Science and Technology, Luoyang 471023, Henan Province, China
| | - Jinming Yang
- Laboratory of Pesticidal Design and Synthesis, Department of Plant Protection, College of Forestry, Henan University of Science and Technology, Luoyang 471023, Henan Province, China
| | - Di Sun
- Laboratory of Pesticidal Design and Synthesis, Department of Plant Protection, College of Forestry, Henan University of Science and Technology, Luoyang 471023, Henan Province, China
| | - Yuee Tian
- Laboratory of Pesticidal Design and Synthesis, Department of Plant Protection, College of Forestry, Henan University of Science and Technology, Luoyang 471023, Henan Province, China
| | - Shengming Liu
- Laboratory of Pesticidal Design and Synthesis, Department of Plant Protection, College of Forestry, Henan University of Science and Technology, Luoyang 471023, Henan Province, China
| | - Xiaomin Lin
- Laboratory of Pesticidal Design and Synthesis, Department of Plant Protection, College of Forestry, Henan University of Science and Technology, Luoyang 471023, Henan Province, China
| | - Jia Jiang
- Laboratory of Pesticidal Design and Synthesis, Department of Plant Protection, College of Forestry, Henan University of Science and Technology, Luoyang 471023, Henan Province, China
| | - Genqiang Chen
- Laboratory of Pesticidal Design and Synthesis, Department of Plant Protection, College of Forestry, Henan University of Science and Technology, Luoyang 471023, Henan Province, China
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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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12
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Pavić K, Rubinić B, Rajić Z, Fontinha D, Prudêncio M, Uzelac L, Kralj M, Held J, Zorc B. Primaquine homodimers as potential antiplasmodial and anticancer agents. Bioorg Med Chem Lett 2019; 29:126614. [PMID: 31431364 DOI: 10.1016/j.bmcl.2019.08.018] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/11/2019] [Revised: 08/08/2019] [Accepted: 08/09/2019] [Indexed: 01/30/2023]
Abstract
Primaquine homodimers, e.g. symmetric PQ-diamides of dicarboxylic acids containing 4 to 8 carbon atoms, were evaluated against Plasmodium berghei hepatic stages and P. falciparum blood stages, as well as against three cancer cell lines. Novel PQ-homodimers exerted much higher activity against hepatic stages, but less pronounced activity against blood stages in comparison to the parent drug. The submicromolar activity of succinic, fumaric and maleic derivatives against P. berghei was determined (IC50 values: 726.2, 198.1 and 358.4 nM, respectively). Our results indicated that the length and type of spacer between two PQ moieties highly modified the antiproliferative activities of PQ-homodimers. The general antiproliferative activity of the adipic and mesaconic derivatives against three cancer cell lines (MCF-7, HCT116, H 460) was observed (GI50 = 1.78-13.7 and 2.36-4.31 µM, respectively), but adipic derivative was less toxic to human embryonic kidney cells (HEK 293). High selectivity of fumaric and suberic derivatives against breast adenocarcinoma cell line MCF-7 was detected. These two compounds have shown no antiproliferative activity against other tumor cells and HEK 293.
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Affiliation(s)
- Kristina Pavić
- University of Zagreb, Faculty of Pharmacy and Biochemistry, 10000 Zagreb, Croatia
| | - Barbara Rubinić
- University of Zagreb, Faculty of Pharmacy and Biochemistry, 10000 Zagreb, Croatia
| | - Zrinka Rajić
- University of Zagreb, Faculty of Pharmacy and Biochemistry, 10000 Zagreb, Croatia
| | - Diana Fontinha
- Instituto de Medicina Molecular, Faculdade de Medicina, Universidade de Lisboa, Lisboa, Portugal
| | - Miguel Prudêncio
- Instituto de Medicina Molecular, Faculdade de Medicina, Universidade de Lisboa, Lisboa, Portugal
| | - Lidija Uzelac
- Laboratory of Experimental Therapy, Division of Molecular Medicine, Rudjer Bošković Institute, 10000 Zagreb, Croatia
| | - Marijeta Kralj
- Laboratory of Experimental Therapy, Division of Molecular Medicine, Rudjer Bošković Institute, 10000 Zagreb, Croatia
| | - Jana Held
- University of Tübingen, Institute of Tropical Medicine, 72074 Tübingen, Germany
| | - Branka Zorc
- University of Zagreb, Faculty of Pharmacy and Biochemistry, 10000 Zagreb, Croatia.
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13
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Triazole derivatives and their antiplasmodial and antimalarial activities. Eur J Med Chem 2019; 166:206-223. [PMID: 30711831 DOI: 10.1016/j.ejmech.2019.01.047] [Citation(s) in RCA: 141] [Impact Index Per Article: 28.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/04/2019] [Revised: 01/19/2019] [Accepted: 01/19/2019] [Indexed: 01/23/2023]
Abstract
Malaria, caused by protozoan parasites of the genus Plasmodium especially by the most prevalent parasite Plasmodium falciparum, represents one of the most devastating and common infectious disease globally. Nearly half of the world population is under the risk of being infected, and more than 200 million new clinical cases with around half a million deaths occur annually. Drug therapy is the mainstay of antimalarial therapy, yet current drugs are threatened by the development of resistance, so it's imperative to develop new antimalarials with great potency against both drug-susceptible and drug-resistant malaria. Triazoles, bearing a five-membered heterocyclic ring with three nitrogen atoms, exhibit promising in vitro antiplasmodial and in vivo antimalarial activities. Moreover, several triazole-based drugs have already used in clinics for the treatment of various diseases, demonstrating the excellent pharmaceutical profiles. Therefore, triazole derivatives have the potential for clinical deployment in the control and eradication of malaria. This review covers the recent advances of triazole derivatives especially triazole hybrids as potential antimalarials. The structure-activity relationship is also discussed to provide an insight for rational designs of more efficient antimalarial candidates.
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14
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Quinoline and quinolone dimers and their biological activities: An overview. Eur J Med Chem 2019; 161:101-117. [DOI: 10.1016/j.ejmech.2018.10.035] [Citation(s) in RCA: 113] [Impact Index Per Article: 22.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/24/2018] [Revised: 10/10/2018] [Accepted: 10/15/2018] [Indexed: 01/28/2023]
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Mechanisms of resistance to the partner drugs of artemisinin in the malaria parasite. Curr Opin Pharmacol 2018; 42:71-80. [PMID: 30142480 DOI: 10.1016/j.coph.2018.07.010] [Citation(s) in RCA: 17] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/02/2018] [Revised: 07/19/2018] [Accepted: 07/26/2018] [Indexed: 01/24/2023]
Abstract
The deployment of artemisinin-based combination therapies (ACTs) has been, and continues to be, integral to reducing the number of malaria cases and deaths. However, their efficacy is being increasingly jeopardized by the emergence and spread of parasites that are resistant (or partially resistant) to the artemisinin derivatives and to their partner drugs, with the efficacy of the latter being especially crucial for treatment success. A detailed understanding of the genetic determinants of resistance to the ACT partner drugs, and the mechanisms by which they mediate resistance, is required for the surveillance of molecular markers and to optimize the efficacy and lifespan of the partner drugs through resistance management strategies. We summarize new insights into the molecular basis of parasite resistance to the ACTs, such as recently-uncovered determinants of parasite susceptibility to the artemisinin derivatives, piperaquine, lumefantrine, and mefloquine, and outline the mechanisms through which polymorphisms in these determinants may be conferring resistance.
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16
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Meier A, Erler H, Beitz E. Targeting Channels and Transporters in Protozoan Parasite Infections. Front Chem 2018; 6:88. [PMID: 29637069 PMCID: PMC5881087 DOI: 10.3389/fchem.2018.00088] [Citation(s) in RCA: 19] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/03/2018] [Accepted: 03/12/2018] [Indexed: 12/25/2022] Open
Abstract
Infectious diseases caused by pathogenic protozoa are among the most significant causes of death in humans. Therapeutic options are scarce and massively challenged by the emergence of resistant parasite strains. Many of the current anti-parasite drugs target soluble enzymes, generate unspecific oxidative stress, or act by an unresolved mechanism within the parasite. In recent years, collections of drug-like compounds derived from large-scale phenotypic screenings, such as the malaria or pathogen box, have been made available to researchers free of charge boosting the identification of novel promising targets. Remarkably, several of the compound hits have been found to inhibit membrane proteins at the periphery of the parasites, i.e., channels and transporters for ions and metabolites. In this review, we will focus on the progress made on targeting channels and transporters at different levels and the potential for use against infections with apicomplexan parasites mainly Plasmodium spp. (malaria) and Toxoplasma gondii (toxoplasmosis), with kinetoplastids Trypanosoma brucei (sleeping sickness), Trypanosoma cruzi (Chagas disease), and Leishmania ssp. (leishmaniasis), and the amoeba Entamoeba histolytica (amoebiasis).
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Affiliation(s)
- Anna Meier
- Department of Pharmaceutical and Medicinal Chemistry, Christian-Albrechts-University of Kiel, Kiel, Germany
| | - Holger Erler
- Department of Pharmaceutical and Medicinal Chemistry, Christian-Albrechts-University of Kiel, Kiel, Germany
| | - Eric Beitz
- Department of Pharmaceutical and Medicinal Chemistry, Christian-Albrechts-University of Kiel, Kiel, Germany
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A Variant PfCRT Isoform Can Contribute to Plasmodium falciparum Resistance to the First-Line Partner Drug Piperaquine. mBio 2017; 8:mBio.00303-17. [PMID: 28487425 PMCID: PMC5424201 DOI: 10.1128/mbio.00303-17] [Citation(s) in RCA: 76] [Impact Index Per Article: 10.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/30/2022] Open
Abstract
Current efforts to reduce the global burden of malaria are threatened by the rapid spread throughout Asia of Plasmodium falciparum resistance to artemisinin-based combination therapies, which includes increasing rates of clinical failure with dihydroartemisinin plus piperaquine (PPQ) in Cambodia. Using zinc finger nuclease-based gene editing, we report that addition of the C101F mutation to the chloroquine (CQ) resistance-conferring PfCRT Dd2 isoform common to Asia can confer PPQ resistance to cultured parasites. Resistance was demonstrated as significantly higher PPQ concentrations causing 90% inhibition of parasite growth (IC90) or 50% parasite killing (50% lethal dose [LD50]). This mutation also reversed Dd2-mediated CQ resistance, sensitized parasites to amodiaquine, quinine, and artemisinin, and conferred amantadine and blasticidin resistance. Using heme fractionation assays, we demonstrate that PPQ causes a buildup of reactive free heme and inhibits the formation of chemically inert hemozoin crystals. Our data evoke inhibition of heme detoxification in the parasite’s acidic digestive vacuole as the primary mode of both the bis-aminoquinoline PPQ and the related 4-aminoquinoline CQ. Both drugs also inhibit hemoglobin proteolysis at elevated concentrations, suggesting an additional mode of action. Isogenic lines differing in their pfmdr1 copy number showed equivalent PPQ susceptibilities. We propose that mutations in PfCRT could contribute to a multifactorial basis of PPQ resistance in field isolates. The global agenda to eliminate malaria depends on the continued success of artemisinin-based combination therapies (ACTs), which target the asexual blood stages of the intracellular parasite Plasmodium. Partial resistance to artemisinin, however, is now established in Southeast Asia, exposing the partner drugs to increased selective pressure. Plasmodium falciparum resistance to the first-line partner piperaquine (PPQ) is now spreading rapidly in Cambodia, resulting in clinical treatment failures. Here, we report that a variant form of the Plasmodium falciparum chloroquine resistance transporter, harboring a C101F mutation edited into the chloroquine (CQ)-resistant Dd2 isoform prevalent in Asia, can confer PPQ resistance in cultured parasites. This was accompanied by a loss of CQ resistance. Biochemical assays showed that PPQ, like CQ, inhibits the detoxification of reactive heme that is formed by parasite-mediated catabolism of host hemoglobin. We propose that novel PfCRT variants emerging in the field could contribute to a multigenic basis of PPQ resistance.
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18
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Evolution of Fitness Cost-Neutral Mutant PfCRT Conferring P. falciparum 4-Aminoquinoline Drug Resistance Is Accompanied by Altered Parasite Metabolism and Digestive Vacuole Physiology. PLoS Pathog 2016; 12:e1005976. [PMID: 27832198 PMCID: PMC5104409 DOI: 10.1371/journal.ppat.1005976] [Citation(s) in RCA: 28] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/15/2016] [Accepted: 10/03/2016] [Indexed: 11/19/2022] Open
Abstract
Southeast Asia is an epicenter of multidrug-resistant Plasmodium falciparum strains. Selective pressures on the subcontinent have recurrently produced several allelic variants of parasite drug resistance genes, including the P. falciparum chloroquine resistance transporter (pfcrt). Despite significant reductions in the deployment of the 4-aminoquinoline drug chloroquine (CQ), which selected for the mutant pfcrt alleles that halted CQ efficacy decades ago, the parasite pfcrt locus is continuously evolving. This is highlighted by the presence of a highly mutated allele, Cam734 pfcrt, which has acquired the singular ability to confer parasite CQ resistance without an associated fitness cost. Here, we used pfcrt-specific zinc-finger nucleases to genetically dissect this allele in the pathogenic setting of asexual blood-stage infection. Comparative analysis of drug resistance and growth profiles of recombinant parasites that express Cam734 or variants thereof, Dd2 (the most common Southeast Asian variant), or wild-type pfcrt, revealed previously unknown roles for PfCRT mutations in modulating parasite susceptibility to multiple antimalarial agents. These results were generated in the GC03 strain, used in multiple earlier pfcrt studies, and might differ in natural isolates harboring this allele. Results presented herein show that Cam734-mediated CQ resistance is dependent on the rare A144F mutation that has not been observed beyond Southeast Asia, and reveal distinct impacts of this and other Cam734-specific mutations on CQ resistance and parasite growth rates. Biochemical assays revealed a broad impact of mutant PfCRT isoforms on parasite metabolism, including nucleoside triphosphate levels, hemoglobin catabolism and disposition of heme, as well as digestive vacuole volume and pH. Results from our study provide new insights into the complex molecular basis and physiological impact of PfCRT-mediated antimalarial drug resistance, and inform ongoing efforts to characterize novel pfcrt alleles that can undermine the efficacy of first-line antimalarial drug regimens. Point mutations in the Plasmodium falciparum chloroquine resistance transporter (PfCRT) earlier thwarted the clinical efficacy of chloroquine, the former gold standard, and constitute a major determinant of parasite susceptibility to antimalarial drugs. Recently, we reported that the highly mutated Cambodian PfCRT isoform Cam734 is fitness-neutral in terms of parasite growth, unlike other less fit isoforms such as Dd2 that are outcompeted by wild-type parasites in the absence of CQ pressure. Using pfcrt-specific zinc-finger nucleases to genetically dissect the Cam734 allele, we report that its unique constituent mutations directly contribute to CQ resistance and collectively offset fitness costs associated with intermediate mutational steps. We also report that these mutations can contribute to resistance or increased sensitivity to multiple first-line partner drugs. Using isogenic parasite lines, we provide evidence of changes in parasite metabolism associated with the Cam734 allele compared to Dd2. We also observe a close correlation between CQ inhibition of hemozoin formation and parasite growth, and provide evidence that Cam734 PfCRT can modulate drug potency depending on its membrane electrochemical gradient. Our data highlight the capacity of PfCRT to evolve new states of antimalarial drug resistance and to offset associated fitness costs through its impact on parasite physiology and hemoglobin catabolism.
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Richards SN, Nash MN, Baker ES, Webster MW, Lehane AM, Shafik SH, Martin RE. Molecular Mechanisms for Drug Hypersensitivity Induced by the Malaria Parasite's Chloroquine Resistance Transporter. PLoS Pathog 2016; 12:e1005725. [PMID: 27441371 PMCID: PMC4956231 DOI: 10.1371/journal.ppat.1005725] [Citation(s) in RCA: 26] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/16/2016] [Accepted: 06/03/2016] [Indexed: 01/23/2023] Open
Abstract
Mutations in the Plasmodium falciparum ‘chloroquine resistance transporter’ (PfCRT) confer resistance to chloroquine (CQ) and related antimalarials by enabling the protein to transport these drugs away from their targets within the parasite’s digestive vacuole (DV). However, CQ resistance-conferring isoforms of PfCRT (PfCRTCQR) also render the parasite hypersensitive to a subset of structurally-diverse pharmacons. Moreover, mutations in PfCRTCQR that suppress the parasite’s hypersensitivity to these molecules simultaneously reinstate its sensitivity to CQ and related drugs. We sought to understand these phenomena by characterizing the functions of PfCRTCQR isoforms that cause the parasite to become hypersensitive to the antimalarial quinine or the antiviral amantadine. We achieved this by measuring the abilities of these proteins to transport CQ, quinine, and amantadine when expressed in Xenopus oocytes and complemented this work with assays that detect the drug transport activity of PfCRT in its native environment within the parasite. Here we describe two mechanistic explanations for PfCRT-induced drug hypersensitivity. First, we show that quinine, which normally accumulates inside the DV and therewithin exerts its antimalarial effect, binds extremely tightly to the substrate-binding site of certain isoforms of PfCRTCQR. By doing so it likely blocks the normal physiological function of the protein, which is essential for the parasite’s survival, and the drug thereby gains an additional killing effect. In the second scenario, we show that although amantadine also sequesters within the DV, the parasite’s hypersensitivity to this drug arises from the PfCRTCQR-mediated transport of amantadine from the DV into the cytosol, where it can better access its antimalarial target. In both cases, the mutations that suppress hypersensitivity also abrogate the ability of PfCRTCQR to transport CQ, thus explaining why rescue from hypersensitivity restores the parasite’s sensitivity to this antimalarial. These insights provide a foundation for understanding clinically-relevant observations of inverse drug susceptibilities in the malaria parasite. In acquiring resistance to one drug, many pathogens and cancer cells become hypersensitive to other drugs. This phenomenon could be exploited to combat existing drug resistance and to delay the emergence of resistance to new drugs. However, much remains to be understood about the mechanisms that underlie drug hypersensitivity in otherwise drug-resistant microbes. Here, we describe two mechanisms by which the Plasmodium falciparum ‘chloroquine resistance transporter’ (PfCRT) causes the malaria parasite to become hypersensitive to structurally-diverse drugs. First, we show that an antimalarial drug that normally exerts its killing effect within the parasite’s digestive vacuole is also able to bind extremely tightly to certain forms of PfCRT. This activity will block the natural, essential function of the protein and thereby provide the drug with an additional killing effect. The second mechanism arises when a cytosolic-acting drug that normally sequesters within the digestive vacuole is leaked back into the cytosol via PfCRT. In both cases, mutations that suppress hypersensitivity also abrogate the ability of PfCRT to transport chloroquine, thus explaining why rescue from hypersensitivity restores the parasite’s sensitivity to this antimalarial. These insights provide a foundation for understanding and exploiting the hypersensitivity of chloroquine-resistant parasites to several of the current antimalarials.
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Affiliation(s)
- Sashika N. Richards
- Research School of Biology, Australian National University, Canberra, Australia
| | - Megan N. Nash
- Research School of Biology, Australian National University, Canberra, Australia
| | - Eileen S. Baker
- Research School of Biology, Australian National University, Canberra, Australia
| | - Michael W. Webster
- Research School of Biology, Australian National University, Canberra, Australia
| | - Adele M. Lehane
- Research School of Biology, Australian National University, Canberra, Australia
| | - Sarah H. Shafik
- Research School of Biology, Australian National University, Canberra, Australia
| | - Rowena E. Martin
- Research School of Biology, Australian National University, Canberra, Australia
- * E-mail:
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Edaye S, Tazoo D, Bohle DS, Georges E. 3-Iodo-4-aminoquinoline derivative sensitises resistant strains of Plasmodium falciparum to chloroquine. Int J Antimicrob Agents 2016; 47:482-5. [PMID: 27211211 DOI: 10.1016/j.ijantimicag.2016.03.016] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/14/2016] [Revised: 03/16/2016] [Accepted: 03/23/2016] [Indexed: 10/21/2022]
Abstract
Chloroquine (CQ), the first cost-effective synthetic antimalarial, is rendered ineffective in malaria-endemic regions owing to the rise and spread of CQ-resistant Plasmodium falciparum. In this report, we show that a halogen derivative of CQ, namely 3-iodo-CQ, inhibits the proliferation of CQ-sensitive and -resistant P. falciparum in a verapamil-insensitive manner. Similar to CQ, the antimalarial activity of 3-iodo-CQ is likely due to its inhibition of β-haematin formation. Interestingly, the presence of non-inhibitory concentrations of 3-iodo-CQ potentiated the antiproliferative activity of CQ against CQ-resistant strains or P. falciparum transfectants expressing wild-type or mutant P. falciparum CQ resistance transporter (PfCRT) (C2(GC03) or C4(Dd2), respectively). These findings demonstrate that halogenation of the third position of 4-aminoquinoline, with a simple one-step reaction from CQ, generates a novel derivative that is active against CQ-sensitive and -resistant P. falciparum, possibly by inhibiting the activity of mutant PfCRT.
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Affiliation(s)
- Sonia Edaye
- Institute of Parasitology, Macdonald Campus, McGill University, Sainte-Anne-de-Bellevue, Quebec H9X 3V9, Canada
| | - Dagobert Tazoo
- Department of Chemistry, McGill University, Quebec, Canada
| | - D Scott Bohle
- Department of Chemistry, McGill University, Quebec, Canada
| | - Elias Georges
- Institute of Parasitology, Macdonald Campus, McGill University, Sainte-Anne-de-Bellevue, Quebec H9X 3V9, Canada.
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Ribeiro-Viana RM, Butera AP, Santos ES, Tischer CA, Alves RB, Pereira de Freitas R, Guimarães L, Varotti FP, Viana GHR, Nascimento CS. Revealing the Binding Process of New 3-Alkylpyridine Marine Alkaloid Analogue Antimalarials and the Heme Group: An Experimental and Theoretical Investigation. J Chem Inf Model 2016; 56:571-9. [DOI: 10.1021/acs.jcim.5b00742] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/19/2022]
Affiliation(s)
- Renato M. Ribeiro-Viana
- Departamento
de Bioquímica e Biotecnologia, CCE, Universidade Estadual de Londrina, Londrina, PR 86057-970, Brazil
| | - Anna P. Butera
- Departamento
de Química, CCE, Universidade Estadual de Londrina, Londrina, PR 86057-970, Brazil
| | - Eliziane S. Santos
- Departamento
de Ciências Naturais (DCNAT), Universidade Federal de São João del-Rei, Campus Dom Bosco, São
João Del Rei, MG 36301-160, Brazil
| | - César A. Tischer
- Departamento
de Bioquímica e Biotecnologia, CCE, Universidade Estadual de Londrina, Londrina, PR 86057-970, Brazil
| | - Rosemeire B. Alves
- Departamento
de Química, Instituto de Ciências Exatas (ICEx), Universidade Federal de Minas Gerais (UFMG), Av. Pres, Antônio Carlos,
6627, Pampulha, Belo Horizonte, MG 31270-901, Brazil
| | - Rossimiriam Pereira de Freitas
- Departamento
de Química, Instituto de Ciências Exatas (ICEx), Universidade Federal de Minas Gerais (UFMG), Av. Pres, Antônio Carlos,
6627, Pampulha, Belo Horizonte, MG 31270-901, Brazil
| | - Luciana Guimarães
- Departamento
de Ciências Naturais (DCNAT), Universidade Federal de São João del-Rei, Campus Dom Bosco, São
João Del Rei, MG 36301-160, Brazil
| | - Fernando P. Varotti
- Núcleo
de Pesquisa em Química Biológica (NQBio), Universidade Federal de São João del-Rei, Campus Centro-Oeste, Divinópolis, MG 35501-296, Brazil
| | - Gustavo H. R. Viana
- Núcleo
de Pesquisa em Química Biológica (NQBio), Universidade Federal de São João del-Rei, Campus Centro-Oeste, Divinópolis, MG 35501-296, Brazil
| | - Clebio S. Nascimento
- Departamento
de Ciências Naturais (DCNAT), Universidade Federal de São João del-Rei, Campus Dom Bosco, São
João Del Rei, MG 36301-160, Brazil
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Verlinden BK, Louw A, Birkholtz LM. Resisting resistance: is there a solution for malaria? Expert Opin Drug Discov 2016; 11:395-406. [PMID: 26926843 DOI: 10.1517/17460441.2016.1154037] [Citation(s) in RCA: 24] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/25/2022]
Abstract
INTRODUCTION Currently, widely used antimalarial drugs have a limited clinical lifespan due to parasite resistance development. With resistance continuously rising, antimalarial drug discovery requires strategies to decrease the time of delivering a new antimalarial drug while simultaneously increasing the drug's therapeutic lifespan. Lessons learnt from various chemotherapeutic resistance studies in the fields of antibiotic and cancer research offer potentially useful strategies that can be applied to antimalarial drug discovery. AREAS COVERED In this review the authors discuss current strategies to circumvent resistance in malaria and alternatives that could be employed. EXPERT OPINION Scientists have been 'beating back' the malaria parasite with novel drugs for the past 49 years but the constant rise in antimalarial drug resistance is forcing the drug discovery community to explore alternative strategies. Avant-garde anti-resistance strategies from alternative fields may assist our endeavors to manage, control and prevent antimalarial drug resistance to progress beyond beating the resistant parasite back, to stopping it dead in its tracks.
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Affiliation(s)
- Bianca K Verlinden
- a Department of Biochemistry, Centre for Sustainable Malaria Control, Faculty of Natural and Agricultural Sciences , University of Pretoria , Pretoria , South Africa
| | - Abraham Louw
- a Department of Biochemistry, Centre for Sustainable Malaria Control, Faculty of Natural and Agricultural Sciences , University of Pretoria , Pretoria , South Africa
| | - Lyn-Marié Birkholtz
- a Department of Biochemistry, Centre for Sustainable Malaria Control, Faculty of Natural and Agricultural Sciences , University of Pretoria , Pretoria , South Africa
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3-Halo Chloroquine Derivatives Overcome Plasmodium falciparum Chloroquine Resistance Transporter-Mediated Drug Resistance in P. falciparum. Antimicrob Agents Chemother 2015; 59:7891-3. [PMID: 26438496 DOI: 10.1128/aac.01139-15] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/17/2015] [Accepted: 09/29/2015] [Indexed: 01/16/2023] Open
Abstract
Polymorphism in the Plasmodium falciparum chloroquine resistance transporter (PfCRT) was shown to cause chloroquine resistance. In this report, we examined the antimalarial potential of novel 3-halo chloroquine derivatives (3-chloro, 3-bromo, and 3-iodo) against chloroquine-susceptible and -resistant P. falciparum. All three derivatives inhibited the proliferation of P. falciparum; with 3-iodo chloroquine being most effective. Moreover, 3-iodo chloroquine was highly effective at potentiating and reversing chloroquine toxicity of drug-susceptible and -resistant P. falciparum.
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24
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Petersen I, Gabryszewski SJ, Johnston GL, Dhingra SK, Ecker A, Lewis RE, de Almeida MJ, Straimer J, Henrich PP, Palatulan E, Johnson DJ, Coburn-Flynn O, Sanchez C, Lehane AM, Lanzer M, Fidock DA. Balancing drug resistance and growth rates via compensatory mutations in the Plasmodium falciparum chloroquine resistance transporter. Mol Microbiol 2015; 97:381-95. [PMID: 25898991 DOI: 10.1111/mmi.13035] [Citation(s) in RCA: 43] [Impact Index Per Article: 4.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 04/17/2015] [Indexed: 11/28/2022]
Abstract
The widespread use of chloroquine to treat Plasmodium falciparum infections has resulted in the selection and dissemination of variant haplotypes of the primary resistance determinant PfCRT. These haplotypes have encountered drug pressure and within-host competition with wild-type drug-sensitive parasites. To examine these selective forces in vitro, we genetically engineered P. falciparum to express geographically diverse PfCRT haplotypes. Variant alleles from the Philippines (PH1 and PH2, which differ solely by the C72S mutation) both conferred a moderate gain of chloroquine resistance and a reduction in growth rates in vitro. Of the two, PH2 showed higher IC50 values, contrasting with reduced growth. Furthermore, a highly mutated pfcrt allele from Cambodia (Cam734) conferred moderate chloroquine resistance and enhanced growth rates, when tested against wild-type pfcrt in co-culture competition assays. These three alleles mediated cross-resistance to amodiaquine, an antimalarial drug widely used in Africa. Each allele, along with the globally prevalent Dd2 and 7G8 alleles, rendered parasites more susceptible to lumefantrine, the partner drug used in the leading first-line artemisinin-based combination therapy. These data reveal ongoing region-specific evolution of PfCRT that impacts drug susceptibility and relative fitness in settings of mixed infections, and raise important considerations about optimal agents to treat chloroquine-resistant malaria.
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Affiliation(s)
- Ines Petersen
- Department of Microbiology and Immunology, Columbia University Medical Center, New York, NY, 10032, USA.,Hygiene Institut, Abteilung Parasitologie, Universitätsklinikum Heidelberg, 69120, Heidelberg, Germany
| | - Stanislaw J Gabryszewski
- Department of Microbiology and Immunology, Columbia University Medical Center, New York, NY, 10032, USA
| | - Geoffrey L Johnston
- Department of Microbiology and Immunology, Columbia University Medical Center, New York, NY, 10032, USA.,School of International and Public Affairs, Columbia University, New York, NY, 10027, USA
| | - Satish K Dhingra
- Department of Microbiology and Immunology, Columbia University Medical Center, New York, NY, 10032, USA.,Department of Biological Sciences, Binghamton University, Binghamton, NY, 13902, USA
| | - Andrea Ecker
- Department of Microbiology and Immunology, Columbia University Medical Center, New York, NY, 10032, USA
| | - Rebecca E Lewis
- Department of Microbiology and Immunology, Columbia University Medical Center, New York, NY, 10032, USA
| | | | - Judith Straimer
- Department of Microbiology and Immunology, Columbia University Medical Center, New York, NY, 10032, USA
| | - Philipp P Henrich
- Department of Microbiology and Immunology, Columbia University Medical Center, New York, NY, 10032, USA
| | - Eugene Palatulan
- Department of Microbiology and Immunology, Columbia University Medical Center, New York, NY, 10032, USA
| | - David J Johnson
- Department of Microbiology and Immunology, Columbia University Medical Center, New York, NY, 10032, USA
| | - Olivia Coburn-Flynn
- Department of Microbiology and Immunology, Columbia University Medical Center, New York, NY, 10032, USA
| | - Cecilia Sanchez
- Hygiene Institut, Abteilung Parasitologie, Universitätsklinikum Heidelberg, 69120, Heidelberg, Germany
| | - Adele M Lehane
- Department of Microbiology and Immunology, Columbia University Medical Center, New York, NY, 10032, USA
| | - Michael Lanzer
- Hygiene Institut, Abteilung Parasitologie, Universitätsklinikum Heidelberg, 69120, Heidelberg, Germany
| | - David A Fidock
- Department of Microbiology and Immunology, Columbia University Medical Center, New York, NY, 10032, USA.,Division of Infectious Diseases, Department of Medicine, Columbia University Medical Center, New York, NY, 10032, USA
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25
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Kumar S, Kumari R, Pandey R. New insight-guided approaches to detect, cure, prevent and eliminate malaria. PROTOPLASMA 2015; 252:717-753. [PMID: 25323622 DOI: 10.1007/s00709-014-0697-x] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/18/2014] [Accepted: 09/01/2014] [Indexed: 06/04/2023]
Abstract
New challenges posed by the development of resistance against artemisinin-based combination therapies (ACTs) as well as previous first-line therapies, and the continuing absence of vaccine, have given impetus to research in all areas of malaria control. This review portrays the ongoing progress in several directions of malaria research. The variants of RTS,S and apical membrane antigen 1 (AMA1) are being developed and test adapted as multicomponent and multistage malaria control vaccines, while many other vaccine candidates and methodologies to produce antigens are under experimentation. To track and prevent the spread of artemisinin resistance from Southeast Asia to other parts of the world, rolling circle-enhanced enzyme activity detection (REEAD), a time- and cost-effective malaria diagnosis in field conditions, and a DNA marker associated with artemisinin resistance have become available. Novel mosquito repellents and mosquito trapping and killing techniques much more effective than the prevalent ones are undergoing field testing. Mosquito lines stably infected with their symbiotic wild-type or genetically engineered bacteria that kill sympatric malaria parasites are being constructed and field tested for stopping malaria transmission. A complementary approach being pursued is the addition of ivermectin-like drug molecules to ACTs to cure malaria and kill mosquitoes. Experiments are in progress to eradicate malaria mosquito by making it genetically male sterile. High-throughput screening procedures are being developed and used to discover molecules that possess long in vivo half life and are active against liver and blood stages for the fast cure of malaria symptoms caused by simple or relapsing and drug-sensitive and drug-resistant types of varied malaria parasites, can stop gametocytogenesis and sporogony and could be given in one dose. Target-based antimalarial drug designing has begun. Some of the putative next-generation antimalarials that possess in their scaffold structure several of the desired properties of malaria cure and control are exemplified by OZ439, NITD609, ELQ300 and tafenoquine that are already undergoing clinical trials, and decoquinate, usnic acid, torin-2, ferroquine, WEHI-916, MMV396749 and benzothiophene-type N-myristoyltransferase (NMT) inhibitors, which are candidates for future clinical usage. Among these, NITD609, ELQ300, decoquinate, usnic acid, torin-2 and NMT inhibitors not only cure simple malaria and are prophylactic against simple malaria, but they also cure relapsing malaria.
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Affiliation(s)
- Sushil Kumar
- SKA Institution for Research, Education and Development (SKAIRED), 4/11 SarvPriya Vihar, New Delhi, 110016, India,
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26
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Plasmodium falciparum chloroquine resistance transporter is a H+-coupled polyspecific nutrient and drug exporter. Proc Natl Acad Sci U S A 2015; 112:3356-61. [PMID: 25733858 DOI: 10.1073/pnas.1417102112] [Citation(s) in RCA: 55] [Impact Index Per Article: 6.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/22/2022] Open
Abstract
Extrusion of chloroquine (CQ) from digestive vacuoles through the Plasmodium falciparum CQ resistance transporter (PfCRT) is essential to establish CQ resistance of the malaria parasite. However, the physiological relevance of PfCRT and how CQ-resistant PfCRT gains the ability to transport CQ remain unknown. We prepared proteoliposomes containing purified CQ-sensitive and CQ-resistant PfCRTs and measured their transport activities. All PfCRTs tested actively took up tetraethylammonium, verapamil, CQ, basic amino acids, polypeptides, and polyamines at the expense of an electrochemical proton gradient. CQ-resistant PfCRT exhibited decreased affinity for CQ, resulting in increased CQ uptake. Furthermore, CQ competitively inhibited amino acid transport. Thus, PfCRT is a H(+)-coupled polyspecific nutrient and drug exporter.
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27
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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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28
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Abstract
Nature is full of dimeric alkaloids of various types from many plant families, some of them with interesting biological properties. However, dimeric Cinchona alkaloids were not isolated from any species but were products of designed partial chemical synthesis. Although the Cinchona bark is amongst the sources of oldest efficient medicines, the synthetic dimers found most use in the field of asymmetric synthesis. Prominent examples include the Sharpless dihydroxylation and aminohydroxylation ligands, and dimeric phase transfer catalysts. In this article the syntheses of Cinchona alkaloid dimers and oligomers are reviewed, and their structure and applications are outlined. Various synthetic routes exploit reactivity of the alkaloids at the central 9-hydroxyl group, quinuclidine, and quinoline rings, as well as 3-vinyl group. This availability of reactive sites, in combination with a plethora of linker molecules, contributes to the diversity of the products obtained.
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Affiliation(s)
- Przemysław J Boratyński
- Department of Organic Chemistry, Wrocław University of Technology, Wyspiańskiego 27, 50-370, Wrocław, Poland,
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29
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Bellanca S, Summers RL, Meyrath M, Dave A, Nash MN, Dittmer M, Sanchez CP, Stein WD, Martin RE, Lanzer M. Multiple drugs compete for transport via the Plasmodium falciparum chloroquine resistance transporter at distinct but interdependent sites. J Biol Chem 2014; 289:36336-51. [PMID: 25378409 PMCID: PMC4276893 DOI: 10.1074/jbc.m114.614206] [Citation(s) in RCA: 28] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022] Open
Abstract
Mutations in the "chloroquine resistance transporter" (PfCRT) are a major determinant of drug resistance in the malaria parasite Plasmodium falciparum. We have previously shown that mutant PfCRT transports the antimalarial drug chloroquine away from its target, whereas the wild-type form of PfCRT does not. However, little is understood about the transport of other drugs via PfCRT or the mechanism by which PfCRT recognizes different substrates. Here we show that mutant PfCRT also transports quinine, quinidine, and verapamil, indicating that the protein behaves as a multidrug resistance carrier. Detailed kinetic analyses revealed that chloroquine and quinine compete for transport via PfCRT in a manner that is consistent with mixed-type inhibition. Moreover, our analyses suggest that PfCRT accepts chloroquine and quinine at distinct but antagonistically interacting sites. We also found verapamil to be a partial mixed-type inhibitor of chloroquine transport via PfCRT, further supporting the idea that PfCRT possesses multiple substrate-binding sites. Our findings provide new mechanistic insights into the workings of PfCRT, which could be exploited to design potent inhibitors of this key mediator of drug resistance.
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Affiliation(s)
- Sebastiano Bellanca
- From the Department of Infectious Diseases, Parasitology, Heidelberg University, Im Neuenheimer Feld 324, 69120 Heidelberg, Germany
| | - Robert L Summers
- the Research School of Biology, Australian National University, Canberra, Australian Capital Territory 0200, Australia, and
| | - Max Meyrath
- From the Department of Infectious Diseases, Parasitology, Heidelberg University, Im Neuenheimer Feld 324, 69120 Heidelberg, Germany
| | - Anurag Dave
- From the Department of Infectious Diseases, Parasitology, Heidelberg University, Im Neuenheimer Feld 324, 69120 Heidelberg, Germany
| | - Megan N Nash
- the Research School of Biology, Australian National University, Canberra, Australian Capital Territory 0200, Australia, and
| | - Martin Dittmer
- From the Department of Infectious Diseases, Parasitology, Heidelberg University, Im Neuenheimer Feld 324, 69120 Heidelberg, Germany
| | - Cecilia P Sanchez
- From the Department of Infectious Diseases, Parasitology, Heidelberg University, Im Neuenheimer Feld 324, 69120 Heidelberg, Germany
| | - Wilfred D Stein
- the Department of Biological Chemistry, Silberman Institute of Life Sciences, Hebrew University of Jerusalem, Jerusalem 91904, Israel
| | - Rowena E Martin
- the Research School of Biology, Australian National University, Canberra, Australian Capital Territory 0200, Australia, and
| | - Michael Lanzer
- From the Department of Infectious Diseases, Parasitology, Heidelberg University, Im Neuenheimer Feld 324, 69120 Heidelberg, Germany,
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