1
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Cardillo NM, Villarino NF, Lacy PA, Doggett JS, Riscoe MK, Suarez CE, Ueti MW, Chung CJ. Enhanced Anti-Babesia Efficacy of Buparvaquone and Imidocarb When Combined with ELQ-316 In Vitro Culture of Babesia bigemina. Pharmaceuticals (Basel) 2025; 18:218. [PMID: 40006032 PMCID: PMC11858768 DOI: 10.3390/ph18020218] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/16/2024] [Revised: 02/03/2025] [Accepted: 02/05/2025] [Indexed: 02/27/2025] Open
Abstract
Background/Objectives:B. bigemina is a highly pathogenic and widely distributed tick-borne disease parasite responsible for bovine babesiosis. The development of effective and safe therapies is urgently needed for global disease control. The aim of this study is to compare the effects of endochin-like quinolone (ELQ-316), buparvaquone (BPQ), imidocarb (ID), and the combinations of ID + ELQ-316 and BPQ + ELQ-316, on in vitro survival of B. bigemina.Methods: Parasites at a starting parasitemia level of 2%, were incubated with each single drug and a combination of drugs, ranging from 25 to 1200 nM of concentration over four consecutive days. The inhibitory concentrations, 50% (IC50%) and 99% (IC99%), were estimated. Parasitemia levels were evaluated daily using microscopic examination. Data were statistically compared using the non-parametrical Kruskall-Wallis test. Results: All drugs tested significantly inhibited (p < 0.05) the growth of B. bigemina at 2% parasitemia. The combination of ID + ELQ-316 exhibited a lower mean (IC50%: 9.2; confidence interval 95%: 8.7-9.9) than ID (IC50%: 61.5; confidence interval 95%: 59.54-63.46), ELQ-316 (IC50%: 48.10; confidence interval 95%: 42.76-58.83), BPQ (IC50%: 44.66; confidence interval 95%: 43.56-45.81), and BPQ + ELQ-316 (IC50%: 27.59; confidence interval: N/A). Parasites were no longer viable in cultures treated with the BPQ + ELQ-316 combination, as well as with BPQ alone at a concentration of 1200 nM, on days 2 and 3 of treatment, respectively. Conclusions: BPQ and ID increase the babesiacidal effect of ELQ-316. The efficacy of these combinations deserves to be evaluated in vivo, which could lead to a promising and safer treatment option for B. bigemina.
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Affiliation(s)
- Natalia M. Cardillo
- Animal Disease Research Unit, USDA-ARS, 3003 ADBF, WSU, Pullman, WA 99163, USA; (P.A.L.); (M.W.U.)
- Department of Veterinary Microbiology and Pathology, Washington State University, Pullman, WA 99164, USA
| | - Nicolas F. Villarino
- Program in Individualized Medicine, Department of Veterinary Clinical Sciences, College of Veterinary Medicine, Washington State University, Pullman, WA 99164, USA;
| | - Paul A. Lacy
- Animal Disease Research Unit, USDA-ARS, 3003 ADBF, WSU, Pullman, WA 99163, USA; (P.A.L.); (M.W.U.)
| | - Joseph S. Doggett
- VA Portland Healthcare System, 3710 SW US Veterans Hospital Road, Portland, OR 97239, USA; (J.S.D.); (M.K.R.)
- School of Medicine, Division of Infectious Diseases, Oregon Health & Science University, 3181 SW Sam Jackson Park Road, Portland, OR 97239, USA
| | - Michael K. Riscoe
- VA Portland Healthcare System, 3710 SW US Veterans Hospital Road, Portland, OR 97239, USA; (J.S.D.); (M.K.R.)
- Department of Microbiology and Molecular Immunology, Oregon Health & Science University, 3181 SW Sam Jackson Park Road, Portland, OR 97239, USA
| | - Carlos E. Suarez
- Department of Veterinary Microbiology and Pathology, Washington State University, Pullman, WA 99164, USA
| | - Massaro W. Ueti
- Animal Disease Research Unit, USDA-ARS, 3003 ADBF, WSU, Pullman, WA 99163, USA; (P.A.L.); (M.W.U.)
- Department of Veterinary Microbiology and Pathology, Washington State University, Pullman, WA 99164, USA
| | - Chungwon J. Chung
- Animal Disease Research Unit, USDA-ARS, 3003 ADBF, WSU, Pullman, WA 99163, USA; (P.A.L.); (M.W.U.)
- Department of Veterinary Microbiology and Pathology, Washington State University, Pullman, WA 99164, USA
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2
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Cardillo NM, Villarino NF, Lacy PA, Riscoe MK, Doggett JS, Ueti MW, Chung CJ, Suarez CE. The Combination of Buparvaquone and ELQ316 Exhibit a Stronger Effect than ELQ316 and Imidocarb Against Babesia bovis In Vitro. Pharmaceutics 2024; 16:1402. [PMID: 39598526 PMCID: PMC11597495 DOI: 10.3390/pharmaceutics16111402] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/24/2024] [Revised: 10/24/2024] [Accepted: 10/29/2024] [Indexed: 11/29/2024] Open
Abstract
Background/Objectives: Bovine babesiosis is a vector-borne disease transmitted by ticks that causes important losses in livestock worldwide. Recent research performed on the drugs currently used to control bovine babesiosis reported several issues including drug resistance, toxicity impact, and residues in edible tissue, suggesting the need for developing novel effective therapies. The endochin-like quinolones ELQ-316 and buparvaquone (BPQ) act as cytochrome bc1 inhibitors and have been proven to be safe and efficacious against related apicomplexans, such as Plasmodium spp. and Babesia microti, without showing toxicity in mammals. The objectives of this study are investigating whether ELQ-316, BPQ, and their combination treatment could be effective against Babesia bovis in an in vitro culture model and comparing with imidocarb (ID), the routinely used drug. Methods: In vitro cultured parasites starting at 2% percentage of parasitemia (PPE) were treated with BPQ, ELQ-316, ID, and the combinations of BPQ + ELQ-316 and ID + ELQ-316 at drug concentrations that ranged from 25 to 1200 nM, during four consecutive days. The IC50% and IC99% were reported. Parasitemia levels were evaluated daily using microscopic examination. Data were compared using the non-parametrical Mann-Whitney and Kruskall-Wallis test. Results: All drugs tested, whether used alone or in combination, significantly decreased the survival (p < 0.05) of B. bovis in in vitro cultures. The combination of BPQ + ELQ-316 had the lowest calculated inhibitory concentration 50% (IC50%) values, 31.21 nM (IC95%: 15.06-68.48); followed by BPQ, 77.06 nM (IC95%: 70.16-86.01); ID + ELQ316, 197 nM (IC95%:129.0-311.2); ID, 635.1 nM (IC95%: 280.9-2119); and ELQ316, 654.9 nM (IC95%: 362.3-1411). Conclusions: The results reinforce the higher efficacy of BPQ at affecting B. bovis survival and the potential synergistic effects of its combination with ELQ-316, providing a promising treatment option against B. bovis.
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Affiliation(s)
- Natalia M. Cardillo
- Animal Disease Research Unit, United States Department of Agriculture-Animal Research Unit (USDA-ARS), 3003 ADBF, WSU, Pullman, WA 99163, USA; (P.A.L.); (M.W.U.); (C.J.C.); (C.E.S.)
- Estación Experimental INTA Paraná, Consejo Nacional de Investigaciones Científicas y Técnicas (CONICET), Buenos Aires 2290, Argentina
- Department of Veterinary Microbiology and Pathology, Washington State University, Pullman, WA 99164, USA
| | - Nicolas F. Villarino
- Program in Individualized Medicine, Department of Veterinary Clinical Sciences, College of Veterinary Medicine, Washington State University, Pullman, WA 99164, USA;
| | - Paul A. Lacy
- Animal Disease Research Unit, United States Department of Agriculture-Animal Research Unit (USDA-ARS), 3003 ADBF, WSU, Pullman, WA 99163, USA; (P.A.L.); (M.W.U.); (C.J.C.); (C.E.S.)
| | - Michael K. Riscoe
- VA Portland Healthcare System, 3710 SW US Veterans Hospital Road, Portland, OR 97239, USA (J.S.D.)
- Department of Microbiology and Molecular Immunology, Oregon Health & Science University, 3181 SW Sam Jackson Park Road, Portland, OR 97239, USA
| | - Joseph Stone Doggett
- VA Portland Healthcare System, 3710 SW US Veterans Hospital Road, Portland, OR 97239, USA (J.S.D.)
- School of Medicine, Division of Infectious Diseases, Oregon Health & Science University, 3181 SW Sam Jackson Park Road, Portland, OR 97239, USA
| | - Massaro W. Ueti
- Animal Disease Research Unit, United States Department of Agriculture-Animal Research Unit (USDA-ARS), 3003 ADBF, WSU, Pullman, WA 99163, USA; (P.A.L.); (M.W.U.); (C.J.C.); (C.E.S.)
- Department of Veterinary Microbiology and Pathology, Washington State University, Pullman, WA 99164, USA
| | - Chungwon J. Chung
- Animal Disease Research Unit, United States Department of Agriculture-Animal Research Unit (USDA-ARS), 3003 ADBF, WSU, Pullman, WA 99163, USA; (P.A.L.); (M.W.U.); (C.J.C.); (C.E.S.)
| | - Carlos E. Suarez
- Animal Disease Research Unit, United States Department of Agriculture-Animal Research Unit (USDA-ARS), 3003 ADBF, WSU, Pullman, WA 99163, USA; (P.A.L.); (M.W.U.); (C.J.C.); (C.E.S.)
- Department of Veterinary Microbiology and Pathology, Washington State University, Pullman, WA 99164, USA
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3
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Sheokand PK, Pradhan S, Maclean AE, Mühleip A, Sheiner L. Plasmodium falciparum Mitochondrial Complex III, the Target of Atovaquone, Is Essential for Progression to the Transmissible Sexual Stages. Int J Mol Sci 2024; 25:9239. [PMID: 39273187 PMCID: PMC11394760 DOI: 10.3390/ijms25179239] [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: 05/07/2024] [Revised: 08/16/2024] [Accepted: 08/18/2024] [Indexed: 09/15/2024] Open
Abstract
The Plasmodium falciparum mitochondrial electron transport chain (mETC) is responsible for essential metabolic pathways such as de novo pyrimidine synthesis and ATP synthesis. The mETC complex III (cytochrome bc1 complex) is responsible for transferring electrons from ubiquinol to cytochrome c and generating a proton gradient across the inner mitochondrial membrane, which is necessary for the function of ATP synthase. Recent studies have revealed that the composition of Plasmodium falciparum complex III (PfCIII) is divergent from humans, highlighting its suitability as a target for specific inhibition. Indeed, PfCIII is the target of the clinically used anti-malarial atovaquone and of several inhibitors undergoing pre-clinical trials, yet its role in parasite biology has not been thoroughly studied. We provide evidence that the universally conserved subunit, PfRieske, and the new parasite subunit, PfC3AP2, are part of PfCIII, with the latter providing support for the prediction of its divergent composition. Using inducible depletion, we show that PfRieske, and therefore, PfCIII as a whole, is essential for asexual blood stage parasite survival, in line with previous observations. We further found that depletion of PfRieske results in gametocyte maturation defects. These phenotypes are linked to defects in mitochondrial functions upon PfRieske depletion, including increased sensitivity to mETC inhibitors in asexual stages and decreased cristae abundance alongside abnormal mitochondrial morphology in gametocytes. This is the first study that explores the direct role of the PfCIII in gametogenesis via genetic disruption, paving the way for a better understanding of the role of mETC in the complex life cycle of these important parasites and providing further support for the focus of antimalarial drug development on this pathway.
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Affiliation(s)
- Pradeep Kumar Sheokand
- Wellcome Centre for Integrative Parasitology, School of Infection and Immunity, University of Glasgow, Glasgow G12 8TA, UK
| | - Sabyasachi Pradhan
- Wellcome Centre for Integrative Parasitology, School of Infection and Immunity, University of Glasgow, Glasgow G12 8TA, UK
| | - Andrew E Maclean
- Wellcome Centre for Integrative Parasitology, School of Infection and Immunity, University of Glasgow, Glasgow G12 8TA, UK
| | - Alexander Mühleip
- Wellcome Centre for Integrative Parasitology, School of Infection and Immunity, University of Glasgow, Glasgow G12 8TA, UK
| | - Lilach Sheiner
- Wellcome Centre for Integrative Parasitology, School of Infection and Immunity, University of Glasgow, Glasgow G12 8TA, UK
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4
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Senkina J, Knapp S. Incorporation of an Isohexide Subunit into the Endochin-like Quinolone Scaffold. Molecules 2024; 29:3615. [PMID: 39125020 PMCID: PMC11314205 DOI: 10.3390/molecules29153615] [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: 06/15/2024] [Revised: 07/24/2024] [Accepted: 07/29/2024] [Indexed: 08/12/2024] Open
Abstract
In order to improve the drug-likeness qualities, the antimalarial endochin-like quinolone (ELQ) scaffold has been modified by replacing the 4-(trifluoromethoxy)phenyl portion with an isoidide unit that is further adjustable by varying the distal O-substituents. As expected, the water solubilities of the new analogs are greatly improved, and the melting points are lower. However, the antimalarial potency of the new analogs is reduced to EC50 > 1 millimolar, a result ascribable to the hydrophilic nature of the new substitution.
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Affiliation(s)
| | - Spencer Knapp
- Department of Chemistry and Chemical Biology, Rutgers, The State University of New Jersey, 123 Bevier Road, Piscataway, NJ 08854, USA;
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5
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Pou S, Winter RW, Liebman KM, Dodean RA, Nilsen A, DeBarber A, Doggett JS, Riscoe MK. Synthesis of Deuterated Endochin-Like Quinolones. J Labelled Comp Radiopharm 2024; 67:186-196. [PMID: 38661253 PMCID: PMC11081819 DOI: 10.1002/jlcr.4092] [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: 01/06/2024] [Revised: 03/05/2024] [Accepted: 03/13/2024] [Indexed: 04/26/2024]
Abstract
Malaria continues to be a serious and debilitating disease. The emergence and spread of high-level resistance to multiple antimalarial drugs by Plasmodium falciparum has brought about an urgent need for new treatments that will be active against multidrug resistant malaria infections. One such treatment, ELQ-331 (MMV-167), an alkoxy carbonate prodrug of 4(1H)-quinolone ELQ-300, is currently in preclinical development with the Medicines for Malaria Venture. Clinical development of ELQ-331 or similar compounds will require the availability of isotopically labeled analogs. Unfortunately, a suitable method for the deuteration of these important compounds was not found in the literature. Here, we describe a facile and scalable method for the deuteration of 4(1H)-quinolone ELQ-300, its alkoxycarbonate prodrug ELQ-331, and their respective N-oxides using deuterated acetic acid.
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Affiliation(s)
- Sovitj Pou
- Medical Research Service, VA Healthcare System, Portland, Oregon, USA
| | - Rolf W Winter
- Medical Research Service, VA Healthcare System, Portland, Oregon, USA
| | | | - Rosie A Dodean
- Medical Research Service, VA Healthcare System, Portland, Oregon, USA
| | - Aaron Nilsen
- Medical Research Service, VA Healthcare System, Portland, Oregon, USA
- Department of Chemical Physiology & Biochemistry, Oregon Health & Science University, Portland, Oregon, USA
| | - Andrea DeBarber
- Department of Chemical Physiology & Biochemistry, Oregon Health & Science University, Portland, Oregon, USA
| | - J Stone Doggett
- Medical Research Service, VA Healthcare System, Portland, Oregon, USA
- Division of Infectious Diseases, School of Medicine, Oregon Health & Science University, Portland, Oregon, USA
| | - Michael K Riscoe
- Medical Research Service, VA Healthcare System, Portland, Oregon, USA
- Department of Molecular Microbiology & Immunology, Oregon Health & Science University, Portland, Oregon, USA
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6
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Vydyam P, Chand M, Pou S, Winter RW, Liebman KM, Nilsen A, Doggett JS, Riscoe MK, Ben Mamoun C. Effectiveness of Two New Endochin-like Quinolones, ELQ-596 and ELQ-650, in Experimental Mouse Models of Human Babesiosis. ACS Infect Dis 2024; 10:1405-1413. [PMID: 38563132 PMCID: PMC11127568 DOI: 10.1021/acsinfecdis.4c00143] [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] [Indexed: 04/04/2024]
Abstract
Endochin-like quinolones (ELQs) define a class of small molecule antimicrobials that target the mitochondrial electron transport chain of various human parasites by inhibiting their cytochrome bc1 complexes. The compounds have shown potent activity against a wide range of protozoan parasites, including the intraerythrocytic parasites Plasmodium and Babesia, the agents of human malaria and babesiosis, respectively. First-generation ELQ compounds were previously found to reduce infection by Babesia microti and Babesia duncani in animal models of human babesiosis but achieved a radical cure only in combination with atovaquone and required further optimization to address pharmacological limitations. Here, we report the identification of two second-generation 3-biaryl ELQ compounds, ELQ-596 and ELQ-650, with potent antibabesial activity in vitro and favorable pharmacological properties. In particular, ELQ-598, a prodrug of ELQ-596, demonstrated high efficacy as an orally administered monotherapy at 10 mg/kg. The compound achieved radical cure in both the chronic model of B. microti-induced babesiosis in immunocompromised mice and the lethal infection model induced by B. duncani in immunocompetent mice. Given its high potency, favorable physicochemical properties, and low toxicity profile, ELQ-596 represents a promising drug for the treatment of human babesiosis.
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Affiliation(s)
- Pratap Vydyam
- Department of Medicine, Yale School of Medicine, New Haven, CT 06520, USA
| | - Meenal Chand
- Department of Medicine, Yale School of Medicine, New Haven, CT 06520, USA
| | - Sovitj Pou
- Experimental Chemotherapy Lab, VA Medical Center, 3710 SW US Veterans Hospital Road, Portland, Oregon 97239
| | - Rolf W. Winter
- Experimental Chemotherapy Lab, VA Medical Center, 3710 SW US Veterans Hospital Road, Portland, Oregon 97239
| | - Katherine M. Liebman
- Experimental Chemotherapy Lab, VA Medical Center, 3710 SW US Veterans Hospital Road, Portland, Oregon 97239
| | - Aaron Nilsen
- Experimental Chemotherapy Lab, VA Medical Center, 3710 SW US Veterans Hospital Road, Portland, Oregon 97239
- Department of Chemical Physiology & Biochemistry, Oregon Health & Science University, 3181 SW Sam Jackson Park Road, Portland, Oregon 97239
| | - J. Stone Doggett
- Experimental Chemotherapy Lab, VA Medical Center, 3710 SW US Veterans Hospital Road, Portland, Oregon 97239
- Department of Medicine, Division of Infectious Diseases, Oregon Health & Science University, 3181 SW Sam Jackson Park Road, Portland, Oregon 97239
| | - Michael K. Riscoe
- Experimental Chemotherapy Lab, VA Medical Center, 3710 SW US Veterans Hospital Road, Portland, Oregon 97239
- Department of Molecular Microbiology and Immunology, Oregon Health & Science University, 3181 SW Sam Jackson Park Road, Portland, Oregon 97239
| | - Choukri Ben Mamoun
- Department of Medicine, Yale School of Medicine, New Haven, CT 06520, USA
- Department of Microbial Pathogenesis, Yale School of Medicine, New Haven, CT 06520, USA
- Department of Pathology, Yale School of Medicine, New Haven, CT 06520, USA
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7
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Esser L, Xia D. Mitochondrial Cytochrome bc1 Complex as Validated Drug Target: A Structural Perspective. Trop Med Infect Dis 2024; 9:39. [PMID: 38393128 PMCID: PMC10892539 DOI: 10.3390/tropicalmed9020039] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/06/2023] [Revised: 01/19/2024] [Accepted: 01/24/2024] [Indexed: 02/25/2024] Open
Abstract
Mitochondrial respiratory chain Complex III, also known as cytochrome bc1 complex or cyt bc1, is a validated target not only for antibiotics but also for pesticides and anti-parasitic drugs. Although significant progress has been made in understanding the mechanisms of cyt bc1 function and inhibition by using various natural and synthetic compounds, important issues remain in overcoming drug resistance in agriculture and in evading cytotoxicity in medicine. In this review, we look at these issues from a structural perspective. After a brief description of the essential and common structural features, we point out the differences among various cyt bc1 complexes of different organisms, whose structures have been determined to atomic resolution. We use a few examples of cyt bc1 structures determined via bound inhibitors to illustrate both conformational changes observed and implications to the Q-cycle mechanism of cyt bc1 function. These structures not only offer views of atomic interactions between cyt bc1 complexes and inhibitors, but they also provide explanations for drug resistance when structural details are coupled to sequence changes. Examples are provided for exploiting structural differences in evolutionarily conserved enzymes to develop antifungal drugs for selectivity enhancement, which offer a unique perspective on differential interactions that can be exploited to overcome cytotoxicity in treating human infections.
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Affiliation(s)
| | - Di Xia
- Laboratory of Cell Biology, Center for Cancer Research, National Cancer Institute, National Institutes of Health, 37 Convent Drive, Room 2122C, Bethesda, MD 20892, USA
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8
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Dine I, Mulugeta E, Melaku Y, Belete M. Recent advances in the synthesis of pharmaceutically active 4-quinolone and its analogues: a review. RSC Adv 2023; 13:8657-8682. [PMID: 36936849 PMCID: PMC10015437 DOI: 10.1039/d3ra00749a] [Citation(s) in RCA: 4] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/03/2023] [Accepted: 03/01/2023] [Indexed: 03/17/2023] Open
Abstract
4-Quinolone and its analogs are heterocyclic classes of organic compounds displaying biologically active and a broad spectrum of pharmaceutical drug scaffolds. 4-Quinolone is the first-line chemotherapeutic treatment for a wide spectrum of bacterial infections. Recently, 4-quinolone and its derivatives have been shown to have the potential to cure and regulate various acute and chronic diseases, including pain, ischemia, immunomodulation, inflammation, malarial, bacterial infection, fungal infection, HIV, and cancer, based on several reports. This review highlights and provides brief information to better understand the development of experimental progress made to date in the synthetic protocol towards 4-quinolone and its analogs. Thus, classical synthesis protocol, metal-free reaction protocol, and transition metal-catalyzed reaction procedures are briefly discussed along with the pharmaceutical activities of selected 4-quinolone derivatives.
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Affiliation(s)
- Ilili Dine
- Department of Applied Chemistry, School of Applied Natural Science, Adama Science and Technology University P.O. Box 1888 Adama Ethiopia
| | - Endale Mulugeta
- Department of Applied Chemistry, School of Applied Natural Science, Adama Science and Technology University P.O. Box 1888 Adama Ethiopia
| | - Yadessa Melaku
- Department of Applied Chemistry, School of Applied Natural Science, Adama Science and Technology University P.O. Box 1888 Adama Ethiopia
| | - Melis Belete
- Department of Applied Chemistry, School of Applied Natural Science, Adama Science and Technology University P.O. Box 1888 Adama Ethiopia
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9
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Nguyen W, Dans MG, Currie I, Awalt JK, Bailey BL, Lumb C, Ngo A, Favuzza P, Palandri J, Ramesh S, Penington J, Jarman KE, Mukherjee P, Chakraborty A, Maier AG, van Dooren GG, Papenfuss T, Wittlin S, Churchyard A, Baum J, Winzeler EA, Baud D, Brand S, Jackson PF, Cowman AF, Sleebs BE. 7- N-Substituted-3-oxadiazole Quinolones with Potent Antimalarial Activity Target the Cytochrome bc1 Complex. ACS Infect Dis 2023; 9:668-691. [PMID: 36853190 PMCID: PMC10012268 DOI: 10.1021/acsinfecdis.2c00607] [Citation(s) in RCA: 12] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/05/2022] [Indexed: 03/01/2023]
Abstract
The development of new antimalarials is required because of the threat of resistance to current antimalarial therapies. To discover new antimalarial chemotypes, we screened the Janssen Jumpstarter library against the P. falciparum asexual parasite and identified the 7-N-substituted-3-oxadiazole quinolone hit class. We established the structure-activity relationship and optimized the antimalarial potency. The optimized analog WJM228 (17) showed robust metabolic stability in vitro, although the aqueous solubility was limited. Forward genetic resistance studies uncovered that WJM228 targets the Qo site of cytochrome b (cyt b), an important component of the mitochondrial electron transport chain (ETC) that is essential for pyrimidine biosynthesis and an established antimalarial target. Profiling against drug-resistant parasites confirmed that WJM228 confers resistance to the Qo site but not Qi site mutations, and in a biosensor assay, it was shown to impact the ETC via inhibition of cyt b. Consistent with other cyt b targeted antimalarials, WJM228 prevented pre-erythrocytic parasite and male gamete development and reduced asexual parasitemia in a P. berghei mouse model of malaria. Correcting the limited aqueous solubility and the high susceptibility to cyt b Qo site resistant parasites found in the clinic will be major obstacles in the future development of the 3-oxadiazole quinolone antimalarial class.
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Affiliation(s)
- William Nguyen
- The
Walter and Eliza Hall Institute of Medical Research, Parkville 3052, Australia
- Department
of Medical Biology, The University of Melbourne, Parkville 3010, Australia
| | - Madeline G. Dans
- The
Walter and Eliza Hall Institute of Medical Research, Parkville 3052, Australia
- Department
of Medical Biology, The University of Melbourne, Parkville 3010, Australia
| | - Iain Currie
- The
Walter and Eliza Hall Institute of Medical Research, Parkville 3052, Australia
- Department
of Medical Biology, The University of Melbourne, Parkville 3010, Australia
| | - Jon Kyle Awalt
- The
Walter and Eliza Hall Institute of Medical Research, Parkville 3052, Australia
- Department
of Medical Biology, The University of Melbourne, Parkville 3010, Australia
| | - Brodie L. Bailey
- The
Walter and Eliza Hall Institute of Medical Research, Parkville 3052, Australia
- Department
of Medical Biology, The University of Melbourne, Parkville 3010, Australia
| | - Chris Lumb
- The
Walter and Eliza Hall Institute of Medical Research, Parkville 3052, Australia
| | - Anna Ngo
- The
Walter and Eliza Hall Institute of Medical Research, Parkville 3052, Australia
| | - Paola Favuzza
- The
Walter and Eliza Hall Institute of Medical Research, Parkville 3052, Australia
- Department
of Medical Biology, The University of Melbourne, Parkville 3010, Australia
| | - Josephine Palandri
- The
Walter and Eliza Hall Institute of Medical Research, Parkville 3052, Australia
- Department
of Medical Biology, The University of Melbourne, Parkville 3010, Australia
| | - Saishyam Ramesh
- Research
School of Biology, The Australian National
University, Canberra 2600, Australia
| | - Jocelyn Penington
- The
Walter and Eliza Hall Institute of Medical Research, Parkville 3052, Australia
- Department
of Medical Biology, The University of Melbourne, Parkville 3010, Australia
| | - Kate E. Jarman
- The
Walter and Eliza Hall Institute of Medical Research, Parkville 3052, Australia
- Department
of Medical Biology, The University of Melbourne, Parkville 3010, Australia
| | | | | | - Alexander G. Maier
- Research
School of Biology, The Australian National
University, Canberra 2600, Australia
| | - Giel G. van Dooren
- Research
School of Biology, The Australian National
University, Canberra 2600, Australia
| | - Tony Papenfuss
- The
Walter and Eliza Hall Institute of Medical Research, Parkville 3052, Australia
- Department
of Medical Biology, The University of Melbourne, Parkville 3010, Australia
| | - Sergio Wittlin
- Swiss
Tropical and Public Health Institute, Kreuzstrasse 2, 4123 Allschwil, Switzerland
- University
of Basel, 4003 Basel, Switzerland
| | - Alisje Churchyard
- Department
of Life Sciences, Imperial College London, South Kensington, SW7
2AZ U.K.
| | - Jake Baum
- Department
of Life Sciences, Imperial College London, South Kensington, SW7
2AZ U.K.
- School
of Biomedical Sciences, University of New
South Wales, Sydney 2031, Australia
| | - Elizabeth A. Winzeler
- School
of Medicine, University of California San
Diego, 9500 Gilman Drive
0760, La Jolla, California 92093, United States
| | - Delphine Baud
- Medicines
for Malaria Venture, Geneva 1215, Switzerland
| | - Stephen Brand
- Medicines
for Malaria Venture, Geneva 1215, Switzerland
| | - Paul F. Jackson
- Global
Public Health, Janssen R&D LLC, La Jolla, California 92121, United States
| | - Alan F. Cowman
- The
Walter and Eliza Hall Institute of Medical Research, Parkville 3052, Australia
- Department
of Medical Biology, The University of Melbourne, Parkville 3010, Australia
| | - Brad E. Sleebs
- The
Walter and Eliza Hall Institute of Medical Research, Parkville 3052, Australia
- Department
of Medical Biology, The University of Melbourne, Parkville 3010, Australia
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10
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Sleda MA, Li ZH, Behera R, Baierna B, Li C, Jumpathong J, Malwal SR, Kawamukai M, Oldfield E, Moreno SNJ. The Heptaprenyl Diphosphate Synthase (Coq1) Is the Target of a Lipophilic Bisphosphonate That Protects Mice against Toxoplasma gondii Infection. mBio 2022; 13:e0196622. [PMID: 36129297 PMCID: PMC9600589 DOI: 10.1128/mbio.01966-22] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/12/2022] [Accepted: 08/15/2022] [Indexed: 11/20/2022] Open
Abstract
Prenyldiphosphate synthases catalyze the reaction of allylic diphosphates with one or more isopentenyl diphosphate molecules to form compounds such as farnesyl diphosphate, used in, e.g., sterol biosynthesis and protein prenylation, as well as longer "polyprenyl" diphosphates, used in ubiquinone and menaquinone biosynthesis. Quinones play an essential role in electron transport and are associated with the inner mitochondrial membrane due to the presence of the polyprenyl group. In this work, we investigated the synthesis of the polyprenyl diphosphate that alkylates the ubiquinone ring precursor in Toxoplasma gondii, an opportunistic pathogen that causes serious disease in immunocompromised patients and the unborn fetus. The enzyme that catalyzes this early step of the ubiquinone synthesis is Coq1 (TgCoq1), and we show that it produces the C35 species heptaprenyl diphosphate. TgCoq1 localizes to the mitochondrion and is essential for in vitro T. gondii growth. We demonstrate that the growth defect of a T. gondii TgCoq1 mutant is rescued by complementation with a homologous TgCoq1 gene or with a (C45) solanesyl diphosphate synthase from Trypanosoma cruzi (TcSPPS). We find that a lipophilic bisphosphonate (BPH-1218) inhibits T. gondii growth at low-nanomolar concentrations, while overexpression of the TgCoq1 enzyme dramatically reduced growth inhibition by the bisphosphonate. Both the severe growth defect of the mutant and the inhibition by BPH-1218 were rescued by supplementation with a long-chain (C30) ubiquinone (UQ6). Importantly, BPH-1218 also protected mice against a lethal T. gondii infection. TgCoq1 thus represents a potential drug target that could be exploited for improved chemotherapy of toxoplasmosis. IMPORTANCE Millions of people are infected with Toxoplasma gondii, and the available treatment for toxoplasmosis is not ideal. Most of the drugs currently used are only effective for the acute infection, and treatment can trigger serious side effects requiring changes in the therapeutic approach. There is, therefore, a compelling need for safe and effective treatments for toxoplasmosis. In this work, we characterize an enzyme of the mitochondrion of T. gondii that can be inhibited by an isoprenoid pathway inhibitor. We present evidence that demonstrates that inhibition of the enzyme is linked to parasite death. In addition, the inhibitor can protect mice against a lethal dose of T. gondii. Our results thus reveal a promising chemotherapeutic target for the development of new medicines for toxoplasmosis.
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Affiliation(s)
- Melissa A. Sleda
- Center for Tropical and Emerging Global Diseases, University of Georgia, Athens, Georgia, USA
- Department of Cellular Biology, University of Georgia, Athens, Georgia, USA
| | - Zhu-Hong Li
- Center for Tropical and Emerging Global Diseases, University of Georgia, Athens, Georgia, USA
| | - Ranjan Behera
- Center for Tropical and Emerging Global Diseases, University of Georgia, Athens, Georgia, USA
| | - Baihetiya Baierna
- Center for Tropical and Emerging Global Diseases, University of Georgia, Athens, Georgia, USA
- Department of Cellular Biology, University of Georgia, Athens, Georgia, USA
| | - Catherine Li
- Center for Tropical and Emerging Global Diseases, University of Georgia, Athens, Georgia, USA
| | - Jomkwan Jumpathong
- Department of Life Sciences, Faculty of Life and Environmental Sciences, Shimane University, Matsue, Japan
| | - Satish R. Malwal
- Department of Chemistry, University of Illinois at Urbana Champaign, Urbana, Illinois, USA
| | - Makoto Kawamukai
- Department of Life Sciences, Faculty of Life and Environmental Sciences, Shimane University, Matsue, Japan
| | - Eric Oldfield
- Department of Chemistry, University of Illinois at Urbana Champaign, Urbana, Illinois, USA
| | - Silvia N. J. Moreno
- Center for Tropical and Emerging Global Diseases, University of Georgia, Athens, Georgia, USA
- Department of Cellular Biology, University of Georgia, Athens, Georgia, USA
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11
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Alday PH, Nilsen A, Doggett JS. Structure-activity relationships of Toxoplasma gondii cytochrome bc1 inhibitors. Expert Opin Drug Discov 2022; 17:997-1011. [PMID: 35772172 PMCID: PMC9561756 DOI: 10.1080/17460441.2022.2096588] [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: 04/18/2022] [Accepted: 06/28/2022] [Indexed: 11/04/2022]
Abstract
INTRODUCTION Toxoplasma gondii is a prolific apicomplexan parasite that infects human and nonhuman animals worldwide and can cause severe brain and eye disease. Safer, more effective therapies for toxoplasmosis are needed. Cytochrome bc1 inhibitors are remarkably effective against toxoplasmosis and other apicomplexan-caused diseases. AREAS COVERED This work reviews T. gondii cytochrome bc1 inhibitors. Emphasis is placed on the structure-activity relationships of these inhibitors with regard to efficacy, pharmacokinetics, selectivity of T. gondii cytochrome bc1 over host, safety, and potential therapeutic strategies. EXPERT OPINION Cytochrome bc1 inhibitors are highly promising compounds for toxoplasmosis that have been effective in clinical and preclinical studies. Clinical experience with atovaquone previously validated cytochrome bc1 as a tractable drug target and, over the past decade, optimization of cytochrome bc1 inhibitors has resulted in improved bioavailability, metabolic stability, potency, blood-brain barrier penetration, and selectivity for the T. gondii cytochrome bc1 over the mammalian bc1. Recent studies have demonstrated preclinical safety, identified novel therapeutic strategies for toxoplasmosis using synergistic combinations or long-acting administration and provided insight into their role in chronic infection. This research has identified drug candidates that are more effective than clinically used drugs in preclinical measures of efficacy.
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Affiliation(s)
- Phil Holland Alday
- Portland VA Medical Center, Portland, Oregon, USA
- Oregon Health & Science University, Portland, Oregon, USA
| | - Aaron Nilsen
- Portland VA Medical Center, Portland, Oregon, USA
- Oregon Health & Science University, Portland, Oregon, USA
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12
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Amporndanai K, Pinthong N, O’Neill PM, Hong WD, Amewu RK, Pidathala C, Berry NG, Leung SC, Ward SA, Biagini GA, Hasnain SS, Antonyuk SV. Targeting the Ubiquinol-Reduction (Q i) Site of the Mitochondrial Cytochrome bc1 Complex for the Development of Next Generation Quinolone Antimalarials. BIOLOGY 2022; 11:biology11081109. [PMID: 35892964 PMCID: PMC9330653 DOI: 10.3390/biology11081109] [Citation(s) in RCA: 6] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 05/18/2022] [Revised: 07/11/2022] [Accepted: 07/18/2022] [Indexed: 11/16/2022]
Abstract
Antimalarials targeting the ubiquinol-oxidation (Qo) site of the Plasmodium falciparum bc1 complex, such as atovaquone, have become less effective due to the rapid emergence of resistance linked to point mutations in the Qo site. Recent findings showed a series of 2-aryl quinolones mediate inhibitions of this complex by binding to the ubiquinone-reduction (Qi) site, which offers a potential advantage in circumventing drug resistance. Since it is essential to understand how 2-aryl quinolone lead compounds bind within the Qi site, here we describe the co-crystallization and structure elucidation of the bovine cytochrome bc1 complex with three different antimalarial 4(1H)-quinolone sub-types, including two 2-aryl quinolone derivatives and a 3-aryl quinolone analogue for comparison. Currently, no structural information is available for Plasmodial cytochrome bc1. Our crystallographic studies have enabled comparison of an in-silico homology docking model of P. falciparum with the mammalian's equivalent, enabling an examination of how binding compares for the 2- versus 3-aryl analogues. Based on crystallographic and computational modeling, key differences in human and P. falciparum Qi sites have been mapped that provide new insights that can be exploited for the development of next-generation antimalarials with greater selective inhibitory activity against the parasite bc1 with improved antimalarial properties.
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Affiliation(s)
- Kangsa Amporndanai
- Molecular Biophysics Group, Institute of Systems, Molecular and Integrative Biology, Faculty of Health and Life Sciences, University of Liverpool, Liverpool L69 7ZB, UK; (K.A.); (N.P.); (S.S.H.)
- Department of Biochemistry, Vanderbilt University School of Medicine, Nashville, TN 37232-0146, USA
| | - Nattapon Pinthong
- Molecular Biophysics Group, Institute of Systems, Molecular and Integrative Biology, Faculty of Health and Life Sciences, University of Liverpool, Liverpool L69 7ZB, UK; (K.A.); (N.P.); (S.S.H.)
- Department of Protozoology, Faculty of Tropical Medicine, Mahidol University, Bangkok 10400, Thailand
| | - Paul M. O’Neill
- Department of Chemistry, University of Liverpool, Liverpool L69 7ZD, UK; (W.D.H.); (R.K.A.); (C.P.); (N.G.B.); (S.C.L.)
- Correspondence: (P.M.O.); (S.V.A.); Tel.: +44-(0)-1517955145 (S.V.A.); +44-(0)-1517943552 (P.M.O.)
| | - W. David Hong
- Department of Chemistry, University of Liverpool, Liverpool L69 7ZD, UK; (W.D.H.); (R.K.A.); (C.P.); (N.G.B.); (S.C.L.)
| | - Richard K. Amewu
- Department of Chemistry, University of Liverpool, Liverpool L69 7ZD, UK; (W.D.H.); (R.K.A.); (C.P.); (N.G.B.); (S.C.L.)
- Department of Chemistry, School of Physical and Mathematical Sciences, University of Ghana, Accra P.O. Box LG 586, Ghana
| | - Chandrakala Pidathala
- Department of Chemistry, University of Liverpool, Liverpool L69 7ZD, UK; (W.D.H.); (R.K.A.); (C.P.); (N.G.B.); (S.C.L.)
- Composite Interceptive Med-Science Laboratories Pvt. Ltd., Bengaluru 60099, Karnataka, India
| | - Neil G. Berry
- Department of Chemistry, University of Liverpool, Liverpool L69 7ZD, UK; (W.D.H.); (R.K.A.); (C.P.); (N.G.B.); (S.C.L.)
| | - Suet C. Leung
- Department of Chemistry, University of Liverpool, Liverpool L69 7ZD, UK; (W.D.H.); (R.K.A.); (C.P.); (N.G.B.); (S.C.L.)
| | - Stephen A. Ward
- Centre for Drugs and Diagnostics, Tropical Disease Biology, Liverpool School of Tropical Medicine, Liverpool L3 5QA, UK; (S.A.W.); (G.A.B.)
| | - Giancarlo A. Biagini
- Centre for Drugs and Diagnostics, Tropical Disease Biology, Liverpool School of Tropical Medicine, Liverpool L3 5QA, UK; (S.A.W.); (G.A.B.)
| | - S. Samar Hasnain
- Molecular Biophysics Group, Institute of Systems, Molecular and Integrative Biology, Faculty of Health and Life Sciences, University of Liverpool, Liverpool L69 7ZB, UK; (K.A.); (N.P.); (S.S.H.)
| | - Svetlana V. Antonyuk
- Molecular Biophysics Group, Institute of Systems, Molecular and Integrative Biology, Faculty of Health and Life Sciences, University of Liverpool, Liverpool L69 7ZB, UK; (K.A.); (N.P.); (S.S.H.)
- Correspondence: (P.M.O.); (S.V.A.); Tel.: +44-(0)-1517955145 (S.V.A.); +44-(0)-1517943552 (P.M.O.)
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13
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Renard I, Ben Mamoun C. Treatment of Human Babesiosis: Then and Now. Pathogens 2021; 10:pathogens10091120. [PMID: 34578153 PMCID: PMC8469882 DOI: 10.3390/pathogens10091120] [Citation(s) in RCA: 38] [Impact Index Per Article: 9.5] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/30/2021] [Revised: 08/23/2021] [Accepted: 08/27/2021] [Indexed: 12/26/2022] Open
Abstract
Babesiosis is an emerging tick-borne disease caused by apicomplexan parasites of the genus Babesia. With its increasing incidence worldwide and the risk of human-to-human transmission through blood transfusion, babesiosis is becoming a rising public health concern. The current arsenal for the treatment of human babesiosis is limited and consists of combinations of atovaquone and azithromycin or clindamycin and quinine. These combination therapies were not designed based on biological criteria unique to Babesia parasites, but were rather repurposed based on their well-established efficacy against other apicomplexan parasites. However, these compounds are associated with mild or severe adverse events and a rapid emergence of drug resistance, thus highlighting the need for new therapeutic strategies that are specifically tailored to Babesia parasites. Herein, we review ongoing babesiosis therapeutic and management strategies and their limitations, and further review current efforts to develop new, effective, and safer therapies for the treatment of this disease.
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14
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Anghel N, Imhof D, Winzer P, Balmer V, Ramseier J, Haenggeli K, Choi R, Hulverson MA, Whitman GR, Arnold SL, Ojo KK, Van Voorhis WC, Doggett JS, Ortega-Mora LM, Hemphill A. Endochin-like quinolones (ELQs) and bumped kinase inhibitors (BKIs): Synergistic and additive effects of combined treatments against Neospora caninum infection in vitro and in vivo. Int J Parasitol Drugs Drug Resist 2021; 17:92-106. [PMID: 34482255 PMCID: PMC8416643 DOI: 10.1016/j.ijpddr.2021.08.007] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/19/2021] [Revised: 08/19/2021] [Accepted: 08/26/2021] [Indexed: 12/30/2022]
Abstract
The apicomplexan parasite Neospora caninum is an important causative agent of congenital neosporosis, resulting in abortion, birth of weak offspring and neuromuscular disorders in cattle, sheep, and many other species. Among several compound classes that are currently being developed, two have been reported to limit the effects of congenital neosporosis: (i) bumped kinase inhibitors (BKIs) target calcium dependent protein kinase 1 (CDPK1), an enzyme that is encoded by an apicoplast-derived gene and found only in apicomplexans and plants. CDPK1 is essential for host cell invasion and egress; (ii) endochin-like quinolones (ELQs) are inhibitors of the cytochrome bc1 complex of the mitochondrial electron transport chain and thus inhibit oxidative phosphorylation. We here report on the in vitro and in vivo activities of BKI-1748, and of ELQ-316 and its respective prodrugs ELQ-334 and ELQ-422, applied either as single-compounds or ELQ-BKI-combinations. In vitro, BKI-1748 and ELQ-316, as well as BKI-1748 and ELQ-334, acted synergistically, while this was not observed for the BKI-1748/ELQ-422 combination treatment. In a N. caninum-infected pregnant BALB/c mouse model, the synergistic effects observed in vitro were not entirely reproduced, but 100% postnatal survival and 100% inhibition of vertical transmission was noted in the group treated with the BKI-1748/ELQ-334 combination. In addition, the combined drug applications resulted in lower neonatal mortality compared to treatments with single drugs.
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Affiliation(s)
- Nicoleta Anghel
- Institute of Parasitology, Vetsuisse Faculty, University of Bern, Switzerland,Graduate School for Cellular and Biomedical Sciences (GCB), University of Bern, Switzerland,Corresponding author. Institute of Parasitology, Vetsuisse Faculty, University of Bern, Switzerland.
| | - Dennis Imhof
- Institute of Parasitology, Vetsuisse Faculty, University of Bern, Switzerland,Graduate School for Cellular and Biomedical Sciences (GCB), University of Bern, Switzerland
| | - Pablo Winzer
- Institute of Parasitology, Vetsuisse Faculty, University of Bern, Switzerland,Graduate School for Cellular and Biomedical Sciences (GCB), University of Bern, Switzerland
| | - Vreni Balmer
- Institute of Parasitology, Vetsuisse Faculty, University of Bern, Switzerland
| | - Jessica Ramseier
- Institute of Parasitology, Vetsuisse Faculty, University of Bern, Switzerland
| | - Kai Haenggeli
- Institute of Parasitology, Vetsuisse Faculty, University of Bern, Switzerland,Graduate School for Cellular and Biomedical Sciences (GCB), University of Bern, Switzerland
| | - Ryan Choi
- Center for Emerging and Re-emerging Infectious Diseases (CERID), Division of Allergy and Infectious Diseases, Department of Medicine, University of Washington School of Medicine, Seattle, WA, USA
| | - Matthew A. Hulverson
- Center for Emerging and Re-emerging Infectious Diseases (CERID), Division of Allergy and Infectious Diseases, Department of Medicine, University of Washington School of Medicine, Seattle, WA, USA
| | - Grant R. Whitman
- Center for Emerging and Re-emerging Infectious Diseases (CERID), Division of Allergy and Infectious Diseases, Department of Medicine, University of Washington School of Medicine, Seattle, WA, USA
| | - Samuel L.M. Arnold
- Center for Emerging and Re-emerging Infectious Diseases (CERID), Division of Allergy and Infectious Diseases, Department of Medicine, University of Washington School of Medicine, Seattle, WA, USA,Department of Pharmaceutics, University of Washington, Seattle, WA, USA
| | - Kayode K. Ojo
- Center for Emerging and Re-emerging Infectious Diseases (CERID), Division of Allergy and Infectious Diseases, Department of Medicine, University of Washington School of Medicine, Seattle, WA, USA
| | - Wesley C. Van Voorhis
- Center for Emerging and Re-emerging Infectious Diseases (CERID), Division of Allergy and Infectious Diseases, Department of Medicine, University of Washington School of Medicine, Seattle, WA, USA,Departments of Global Health and Microbiology, University of Washington, Seattle, WA, USA
| | - J. Stone Doggett
- VA Portland Health Care System, Research and Development Service, Portland, OR, USA
| | - Luis M. Ortega-Mora
- SALUVET, Animal Health Department, Faculty of Veterinary Sciences, Complutense University of Madrid, Ciudad Universitaria s/n, Madrid, Spain
| | - Andrew Hemphill
- Institute of Parasitology, Vetsuisse Faculty, University of Bern, Switzerland,Corresponding author.
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15
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Pou S, Dodean RA, Frueh L, Liebman KM, Gallagher RT, Jin H, Jacobs RT, Nilsen A, Stuart DR, Doggett JS, Riscoe MK, Winter RW. A New Scalable Synthesis of ELQ-300, ELQ-316, and other Antiparasitic Quinolones. Org Process Res Dev 2021; 25:1841-1852. [PMID: 35110959 DOI: 10.1021/acs.oprd.1c00099] [Citation(s) in RCA: 9] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/31/2022]
Abstract
The Endochin-Like Quinolone (ELQ) compound class may yield effective, safe treatments for a range of important human and animal afflictions. However, to access the public health potential of this compound series, a synthetic route needed to be devised that lowers costs and is amenable to large scale production. In the new synthetic route described here, a substituted β-keto ester, formed by an Ullmann reaction and subsequent acylation, is reacted with an aniline via a Conrad-Limpach reaction to produce 3-substituted 4(1H)-quinolones such as ELQ-300 and ELQ-316. This synthetic route, the first described to be truly amenable to industrial scale production, is relatively short (5 reaction steps), does not require palladium, chromatographic separation or protecting group chemistry, and may be performed without high vacuum distillation.
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Affiliation(s)
- Sovitj Pou
- VA Portland Healthcare System, 3710 SW US Veterans Hospital Road, Portland, Oregon 97239, United States
| | - Rozalia A Dodean
- VA Portland Healthcare System, 3710 SW US Veterans Hospital Road, Portland, Oregon 97239, United States
| | - Lisa Frueh
- VA Portland Healthcare System, 3710 SW US Veterans Hospital Road, Portland, Oregon 97239, United States
| | - Katherine M Liebman
- VA Portland Healthcare System, 3710 SW US Veterans Hospital Road, Portland, Oregon 97239, United States
| | - Rory T Gallagher
- Department of Chemistry, Portland State University, 1719 SW 10 Avenue, Portland, Oregon 97201, United States
| | - Haihong Jin
- Medicinal Chemistry Core, Oregon Health & Science University, 3181 SW Sam Jackson Park Road, Portland, Oregon 97239, United States
| | - Robert T Jacobs
- Medicines for Malaria Venture, ICC, route de Pré-Bois 20, P.O. Box 1826, 1215 Geneva 15, Switzerland
| | - Aaron Nilsen
- VA Portland Healthcare System, 3710 SW US Veterans Hospital Road, Portland, Oregon 97239, United States.,Medicinal Chemistry Core, Oregon Health & Science University, 3181 SW Sam Jackson Park Road, Portland, Oregon 97239, United States
| | - David R Stuart
- Department of Chemistry, Portland State University, 1719 SW 10 Avenue, Portland, Oregon 97201, United States
| | - J Stone Doggett
- VA Portland Healthcare System, 3710 SW US Veterans Hospital Road, Portland, Oregon 97239, United States.,School of Medicine Division of Infectious Diseases, Oregon Health & Science University, 3181 SW Sam Jackson Park Road, Portland, Oregon 97239, United States
| | - Michael K Riscoe
- VA Portland Healthcare System, 3710 SW US Veterans Hospital Road, Portland, Oregon 97239, United States.,Department of Microbiology and Molecular Immunology, Oregon Health & Science University, 3181 SW Sam Jackson Park Road, Portland, Oregon 97239, United States
| | - Rolf W Winter
- VA Portland Healthcare System, 3710 SW US Veterans Hospital Road, Portland, Oregon 97239, United States
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16
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Effective Therapy Targeting Cytochrome bc1 Prevents Babesia Erythrocytic Development and Protects from Lethal Infection. Antimicrob Agents Chemother 2021; 65:e0066221. [PMID: 34152821 PMCID: PMC8370247 DOI: 10.1128/aac.00662-21] [Citation(s) in RCA: 20] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/17/2023] Open
Abstract
An effective strategy to control blood-borne diseases and prevent outbreak recrudescence involves targeting conserved metabolic processes that are essential for pathogen viability. One such target for Plasmodium and Babesia, the infectious agents of malaria and babesiosis, respectively, is the mitochondrial cytochrome bc1 protein complex, which can be inhibited by endochin-like quinolones (ELQ) and atovaquone. We used the tick-transmitted and culturable blood-borne pathogen Babesia duncani to evaluate the structure-activity relationship, safety, efficacy, and mode of action of ELQs. We identified a potent and highly selective ELQ prodrug (ELQ-502), which, alone or in combination with atovaquone, eliminates B. microti and B. duncani infections in vitro and in mouse models of parasitemia and lethal infection. The strong efficacy at low dose, excellent safety, bioavailability, and long half-life of this experimental therapy make it an ideal clinical candidate for the treatment of human infections caused by Babesia and its closely related apicomplexan parasites.
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17
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Monastyrskyi A, Brockmeyer F, LaCrue AN, Zhao Y, Maher SP, Maignan JR, Padin-Irizarry V, Sakhno YI, Parvatkar PT, Asakawa AH, Huang L, Casandra D, Mashkouri S, Kyle DE, Manetsch R. Aminoalkoxycarbonyloxymethyl Ether Prodrugs with a pH-Triggered Release Mechanism: A Case Study Improving the Solubility, Bioavailability, and Efficacy of Antimalarial 4(1 H)-Quinolones with Single Dose Cures. J Med Chem 2021; 64:6581-6595. [PMID: 33979164 DOI: 10.1021/acs.jmedchem.0c01104] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/04/2023]
Abstract
Preclinical and clinical development of numerous small molecules is prevented by their poor aqueous solubility, limited absorption, and oral bioavailability. Herein, we disclose a general prodrug approach that converts promising lead compounds into aminoalkoxycarbonyloxymethyl (amino AOCOM) ether-substituted analogues that display significantly improved aqueous solubility and enhanced oral bioavailability, restoring key requirements typical for drug candidate profiles. The prodrug is completely independent of biotransformations and animal-independent because it becomes an active compound via a pH-triggered intramolecular cyclization-elimination reaction. As a proof-of-concept, the utility of this novel amino AOCOM ether prodrug approach was demonstrated on an antimalarial compound series representing a variety of antimalarial 4(1H)-quinolones, which entered and failed preclinical development over the last decade. With the amino AOCOM ether prodrug moiety, the 3-aryl-4(1H)-quinolone preclinical candidate was shown to provide single-dose cures in a rodent malaria model at an oral dose of 3 mg/kg, without the use of an advanced formulation technique.
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Affiliation(s)
- Andrii Monastyrskyi
- Department of Chemistry, University of South Florida, CHE 205, 4202 E. Fowler Avenue, Tampa, Florida 33620, United States
| | - Fabian Brockmeyer
- Department of Chemistry and Chemical Biology, Northeastern University, 360 Huntington Avenue, 102 Hurtig Hall, Boston, Massachusetts 02115, United States
| | - Alexis N LaCrue
- Department of Global Health, College of Public Health, University of South Florida, 3720 Spectrum Blvd, Suite 304, Tampa, Florida 33612, United States
| | - Yingzhao Zhao
- Department of Chemistry and Chemical Biology, Northeastern University, 360 Huntington Avenue, 102 Hurtig Hall, Boston, Massachusetts 02115, United States
| | - Steven P Maher
- Center for Tropical and Emerging Global Diseases, University of Georgia, Athens, Coverdell Center, Rm 370B, 500 DW Brooks Drive, Athens, Georgia 30602, United States
| | - Jordany R Maignan
- Department of Chemistry, University of South Florida, CHE 205, 4202 E. Fowler Avenue, Tampa, Florida 33620, United States
| | - Vivian Padin-Irizarry
- Department of Biology, Clayton State University, 2000 Clayton State Boulevard, Morrow, Georgia 30260, United States.,Center for Tropical and Emerging Global Diseases, University of Georgia, Athens, Coverdell Center, Rm 370B, 500 DW Brooks Drive, Athens, Georgia 30602, United States
| | - Yana I Sakhno
- Department of Chemistry, University of South Florida, CHE 205, 4202 E. Fowler Avenue, Tampa, Florida 33620, United States
| | - Prakash T Parvatkar
- Department of Chemistry and Chemical Biology, Northeastern University, 360 Huntington Avenue, 102 Hurtig Hall, Boston, Massachusetts 02115, United States
| | - Ami H Asakawa
- Department of Pharmaceutical Sciences, Northeastern University, 102 Hurtig Hall, 360 Huntington Avenue, Boston, Massachusetts 02115, United States
| | - Lili Huang
- Department of Chemistry and Chemical Biology, Northeastern University, 360 Huntington Avenue, 102 Hurtig Hall, Boston, Massachusetts 02115, United States
| | - Debora Casandra
- Department of Global Health, College of Public Health, University of South Florida, 3720 Spectrum Blvd, Suite 304, Tampa, Florida 33612, United States
| | - Sherwin Mashkouri
- Department of Global Health, College of Public Health, University of South Florida, 3720 Spectrum Blvd, Suite 304, Tampa, Florida 33612, United States
| | - Dennis E Kyle
- Department of Global Health, College of Public Health, University of South Florida, 3720 Spectrum Blvd, Suite 304, Tampa, Florida 33612, United States.,Center for Tropical and Emerging Global Diseases, University of Georgia, Athens, Coverdell Center, Rm 370B, 500 DW Brooks Drive, Athens, Georgia 30602, United States
| | - Roman Manetsch
- Department of Chemistry, University of South Florida, CHE 205, 4202 E. Fowler Avenue, Tampa, Florida 33620, United States.,Department of Chemistry and Chemical Biology, Northeastern University, 360 Huntington Avenue, 102 Hurtig Hall, Boston, Massachusetts 02115, United States.,Department of Pharmaceutical Sciences, Northeastern University, 102 Hurtig Hall, 360 Huntington Avenue, Boston, Massachusetts 02115, United States
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18
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Sharma V, Das R, Mehta DK, Sharma D, Sahu RK. Exploring quinolone scaffold: Unravelling the chemistry of anticancer drug design. Mini Rev Med Chem 2021; 22:69-88. [PMID: 33438536 DOI: 10.2174/1389557521666210112142136] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/24/2020] [Revised: 10/24/2020] [Accepted: 11/30/2020] [Indexed: 11/22/2022]
Abstract
Globally, cancer is considered as the major leading cause in decreasing the patient health care system of human beings. The growing threat from drug-resistant cancers makes heterocyclic moieties as an urgent need to develop more successful candidates for anti-cancer therapy. In view of outstanding pharmacological activities Quinolone and its derivatives have attracted more attention towards drug designing and biological evaluation in the search of new drug molecules. The inspired researchers attempted efforts in order to discover quinolone based analogs due to its wide range of biological activities. Due to immense pharmacological importance, distinct synthetic methods have been executed to attain new drug entities from quinolones and all the reported molecules have shown constructive anticancer activity. Some of the synthetic protocol like, one pot synthesis, post-Ugi-transformation, catalysed based synthesis, enzyme-based synthesis and nano-catalyst based synthetic procedures are also discussed as recent advancement in production of quinolone derivatives. In this review, recent synthetic approaches in the medicinal chemistry of quinolones and potent quinolone derivatives on the basis of structural activity relationship are outlined. Moreover, their major methods and modifications are discussed.
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Affiliation(s)
- Vishal Sharma
- MM College of Pharmacy, Maharishi Markandeshwar (Deemed to be University), Mullana, Ambala, Hr. India
| | - Rina Das
- MM College of Pharmacy, Maharishi Markandeshwar (Deemed to be University), Mullana, Ambala, Hr. India
| | - Dinesh Kumar Mehta
- MM College of Pharmacy, Maharishi Markandeshwar (Deemed to be University), Mullana, Ambala, Hr. India
| | - Diksha Sharma
- Faculty of Pharmaceutical Sciences, Kurukshetra University, Kurukshetra-Hr. India
| | - Ram Kumar Sahu
- Dept of Pharmaceutical Science, Assam University (A Central University), Silchar, Assam-788011. India
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Silva MG, Bastos RG, Stone Doggett J, Riscoe MK, Pou S, Winter R, Dodean RA, Nilsen A, Suarez CE. Endochin-like quinolone-300 and ELQ-316 inhibit Babesia bovis, B. bigemina, B. caballi and Theileria equi. Parasit Vectors 2020; 13:606. [PMID: 33272316 PMCID: PMC7712603 DOI: 10.1186/s13071-020-04487-3] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/11/2020] [Accepted: 11/17/2020] [Indexed: 11/17/2022] Open
Abstract
Background The most common apicomplexan parasites causing bovine babesiosis are Babesia bovis and B. bigemina, while B. caballi and Theileria equi are responsible for equine piroplasmosis. Treatment and control of these diseases are usually achieved using potentially toxic chemotherapeutics, such as imidocarb diproprionate, but drug-resistant parasites are emerging, and alternative effective and safer drugs are needed. The endochin-like quinolones (ELQ)-300 and ELQ-316 have been proven to be safe and efficacious against related apicomplexans, such as Plasmodium spp., with ELQ-316 also being effective against Babesia microti, without showing toxicity in mammals. Methods The inhibitory effects of ELQ-300 and ELQ-316 were assessed on the growth of cultured B. bovis, B. bigemina, B. caballi and T. equi. The percentage of parasitized erythrocytes was measured by flow cytometry, and the effect of the ELQ compounds on the viability of horse and bovine peripheral blood mononuclear cells (PBMC) was assessed by monitoring cell metabolic activity using a colorimetric assay. Results We calculated the half maximal inhibitory concentration (IC50) at 72 h, which ranged from 0.04 to 0.37 nM for ELQ-300, and from 0.002 to 0.1 nM for ELQ-316 among all cultured parasites tested at 72 h. None of the parasites tested were able to replicate in cultures in the presence of ELQ-300 and ELQ-316 at the maximal inhibitory concentration (IC100), which ranged from 1.3 to 5.7 nM for ELQ-300 and from 1.0 to 6.0 nM for ELQ-316 at 72 h. Neither ELQ-300 nor ELQ-316 altered the viability of equine and bovine PBMC at their IC100 in in vitro testing. Conclusions The compounds ELQ-300 and ELQ-316 showed significant inhibitory activity on the main parasites responsible for bovine babesiosis and equine piroplasmosis at doses that are tolerable to host cells. These ELQ drugs may be viable candidates for developing alternative protocols for the treatment of bovine babesiosis and equine piroplasmosis. ![]()
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Affiliation(s)
- Marta G Silva
- Department of Veterinary Microbiology and Pathology, College of Veterinary Medicine, Washington State University, Pullman, WA, USA.
| | - Reginaldo G Bastos
- Department of Veterinary Microbiology and Pathology, College of Veterinary Medicine, Washington State University, Pullman, WA, USA
| | - J Stone Doggett
- Oregon Health and Science University, 3181 SW Sam Jackson Blvd., Portland, Oregon, 97239, USA
| | - Michael K Riscoe
- Oregon Health and Science University, 3181 SW Sam Jackson Blvd., Portland, Oregon, 97239, USA
| | - Sovitj Pou
- VA Portland Health Care System, 3710 SW US Veterans Hospital Road, Portland, OR, 97239, USA
| | - Rolf Winter
- VA Portland Health Care System, 3710 SW US Veterans Hospital Road, Portland, OR, 97239, USA
| | - Rozalia A Dodean
- VA Portland Health Care System, 3710 SW US Veterans Hospital Road, Portland, OR, 97239, USA
| | - Aaron Nilsen
- Oregon Health and Science University, 3181 SW Sam Jackson Blvd., Portland, Oregon, 97239, USA.,VA Portland Health Care System, 3710 SW US Veterans Hospital Road, Portland, OR, 97239, USA
| | - Carlos E Suarez
- Department of Veterinary Microbiology and Pathology, College of Veterinary Medicine, Washington State University, Pullman, WA, USA. .,Animal Disease Research Unit, Agricultural Research Service, USDA, WSU, Pullman, WA, USA.
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Abstract
As the world gets closer to eliminating malaria, the scientific community worldwide has begun to realize the importance of malaria transmission-blocking interventions. The onus of breaking the life cycle of the human malaria parasite Plasmodium falciparum predominantly rests upon transmission-blocking drugs because of emerging resistance to commonly used schizonticides and insecticides. This third part of our review series on malaria transmission-blocking entails transmission-blocking potential of preclinical transmission-blocking antimalarials and other non-malaria drugs/experimental compounds that are not in clinical or preclinical development for malaria but possess transmission-blocking potential. Collective analysis of the structure and the activity of these experimental compounds might pave the way toward generation of novel prototypes of next-generation transmission-blocking drugs.
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21
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Novel Endochin-Like Quinolones Exhibit Potent In Vitro Activity against Plasmodium knowlesi but Do Not Synergize with Proguanil. Antimicrob Agents Chemother 2020; 64:AAC.02549-19. [PMID: 32094134 DOI: 10.1128/aac.02549-19] [Citation(s) in RCA: 10] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/20/2019] [Accepted: 02/21/2020] [Indexed: 12/16/2022] Open
Abstract
Quinolones, such as the antimalarial atovaquone, are inhibitors of the malarial mitochondrial cytochrome bc 1 complex, a target critical to the survival of both liver- and blood-stage parasites, making these drugs useful as both prophylaxis and treatment. Recently, several derivatives of endochin have been optimized to produce novel quinolones that are active in vitro and in animal models. While these quinolones exhibit potent ex vivo activity against Plasmodium falciparum and Plasmodium vivax, their activity against the zoonotic agent Plasmodium knowlesi is unknown. We screened several of these novel endochin-like quinolones (ELQs) for their activity against P. knowlesi in vitro and compared this with their activity against P. falciparum tested under identical conditions. We demonstrated that ELQs are potent against P. knowlesi (50% effective concentration, <117 nM) and equally effective against P. falciparum We then screened selected quinolones and partner drugs using a longer exposure (2.5 life cycles) and found that proguanil is 10-fold less potent against P. knowlesi than P. falciparum, while the quinolones demonstrate similar potency. Finally, we used isobologram analysis to compare combinations of the ELQs with either proguanil or atovaquone. We show that all quinolone combinations with proguanil are synergistic against P. falciparum However, against P. knowlesi, no evidence of synergy between proguanil and the quinolones was found. Importantly, the combination of the novel quinolone ELQ-300 with atovaquone was synergistic against both species. Our data identify potentially important species differences in proguanil susceptibility and in the interaction of proguanil with quinolones and support the ongoing development of novel quinolones as potent antimalarials that target multiple species.
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22
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Eberhard N, Balmer V, Müller J, Müller N, Winter R, Pou S, Nilsen A, Riscoe M, Francisco S, Leitao A, Doggett JS, Hemphill A. Activities of Endochin-Like Quinolones Against in vitro Cultured Besnoitia besnoiti Tachyzoites. Front Vet Sci 2020; 7:96. [PMID: 32161765 PMCID: PMC7054222 DOI: 10.3389/fvets.2020.00096] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/26/2019] [Accepted: 02/10/2020] [Indexed: 12/14/2022] Open
Abstract
Endochin-like quinolones (ELQs) potently inhibit the proliferation of Plasmodium, Toxoplasma, Neospora, and Babesia by targeting the cytochrome b Qo and Qi sites and interfering with oxidative phosphorylation and pyrimidine biosynthesis. The activities of 14 different ELQs were assessed against B. besnoiti tachyzoites grown in human foreskin fibroblasts (HFF) by quantitative real time PCR. The values for 50% proliferation inhibition (IC50) of five ELQs were determined in a 3-days growth assay after an initial screen of 12 ELQs at 0.01, 0.1, and 1 μM. The IC50s of ELQ-121, -136, and -316 were 0.49, 2.36, and 7.97 nM, respectively. The IC50s of ELQs tested against B. besnoiti were higher than IC50s previously observed for P. falciparum and T. gondii. However, the B. besnoiti cytochrome b sequence and the predicted Qo and Qi ELQ binding sites in the Toxoplasma, Neospora, and Besnoitia cytochrome b are virtually identical, suggesting that the differences in ELQ susceptibility are not due to variations in the substrate binding sites. TEM of ELQ-treated parasites primarily demonstrated alterations within the parasite mitochondrion, profound thickening of the nuclear membrane, as well as increased vacuolization within the tachyzoite cytoplasm. Long-term treatment assays of intracellular B. besnoiti with ELQs for up to 20 days followed by the release of drug pressure caused a substantial delay in parasite growth and proliferation while ELQs were present, but parasite proliferation resumed days after ELQs were removed. Interestingly, structural alterations persisted after ELQ removal and parasite proliferation was slowed. These findings provide a basis for further in vivo studies of ELQs as therapeutic options against B. besnoiti infection.
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Affiliation(s)
- Naja Eberhard
- Vetsuisse Faculty, Institute of Parasitology, University of Bern, Bern, Switzerland
| | - Vreni Balmer
- Vetsuisse Faculty, Institute of Parasitology, University of Bern, Bern, Switzerland
| | - Joachim Müller
- Vetsuisse Faculty, Institute of Parasitology, University of Bern, Bern, Switzerland
| | - Norbert Müller
- Vetsuisse Faculty, Institute of Parasitology, University of Bern, Bern, Switzerland
| | - Rolf Winter
- VA Portland Health Care System Research and Development Service, Portland, OR, United States
| | - Soviti Pou
- VA Portland Health Care System Research and Development Service, Portland, OR, United States
| | - Aaron Nilsen
- VA Portland Health Care System Research and Development Service, Portland, OR, United States
| | - Mike Riscoe
- VA Portland Health Care System Research and Development Service, Portland, OR, United States
| | - Samuel Francisco
- Faculdade de Medicina Veterinária, CIISA—Centro de Investigação Interdisciplinar em Sanidade Animal, Universidade de Lisboa, Lisbon, Portugal
| | - Alexandre Leitao
- Faculdade de Medicina Veterinária, CIISA—Centro de Investigação Interdisciplinar em Sanidade Animal, Universidade de Lisboa, Lisbon, Portugal
| | - J. Stone Doggett
- VA Portland Health Care System Research and Development Service, Portland, OR, United States
| | - Andrew Hemphill
- Vetsuisse Faculty, Institute of Parasitology, University of Bern, Bern, Switzerland
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23
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Potharaju S, Mutyam SK, Liu M, Green C, Frueh L, Nilsen A, Pou S, Winter R, Riscoe MK, Shankar G. Improving solubility and oral bioavailability of a novel antimalarial prodrug: comparing spray-dried dispersions with self-emulsifying drug delivery systems. Pharm Dev Technol 2020; 25:625-639. [PMID: 32031478 DOI: 10.1080/10837450.2020.1725893] [Citation(s) in RCA: 10] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/25/2022]
Abstract
To improve the solubility and oral bioavailability of a novel antimalarial agent ELQ-331(a prodrug of ELQ-300), spray-dried dispersions (SDD) and a self-emulsifying drug delivery system (SEDDS) were developed. SDD were prepared with polyvinyl caprolactam-polyvinyl acetate-polyethylene glycol graft copolymer (Soluplus®) polymer carrier and Aeroperl® 300 Pharma and characterized by differential scanning calorimetry, powder X-ray diffraction. For SEDDS, solubility in oils, surfactants, and co-surfactants was determined and ternary phase diagram was constructed to show self-emulsifying area. SEDDS were characterized for spontaneous emulsification and droplet size distribution. The amorphous ELQ-331 SDD improved the solubility to 10× in fast-state simulated intestinal fluid and addition of sodium lauryl sulphate externally to SDDs further improved the solubility to ∼28.5× versus non-formulated drug. SEDDS had good self-emulsifying characteristics with small emulsion droplet sizes and narrow particle distribution. Oral pharmacokinetic studies for SDD and SEDDS formulations were performed in rats. The ELQ-331 rapidly converted to ELQ-300 soon after oral administration in rats. Exposure levels of ELQ-300 were about 1.4-fold higher (based on AUC) in SEDDS than SDD formulations. Poorly soluble drugs like ELQ-331 can be formulated using SDD or SEDDS to improve solubility and oral bioavailability.
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Affiliation(s)
- Suresh Potharaju
- Biosciences Division, Pharmaceutical Sciences Laboratories, SRI International, Menlo Park, CA, USA
| | - Shravan Kumar Mutyam
- Biosciences Division, Pharmaceutical Sciences Laboratories, SRI International, Menlo Park, CA, USA
| | - Mingtao Liu
- Biosciences Division, Pharmaceutical Sciences Laboratories, SRI International, Menlo Park, CA, USA
| | - Carol Green
- Biosciences Division, Pharmaceutical Sciences Laboratories, SRI International, Menlo Park, CA, USA
| | - Lisa Frueh
- Experimental Chemotherapy Lab, VA Medical Center, Portland, OR, USA
| | - Aaron Nilsen
- Experimental Chemotherapy Lab, VA Medical Center, Portland, OR, USA
| | - Sovitj Pou
- Experimental Chemotherapy Lab, VA Medical Center, Portland, OR, USA
| | - Rolf Winter
- Experimental Chemotherapy Lab, VA Medical Center, Portland, OR, USA
| | - Michael K Riscoe
- Experimental Chemotherapy Lab, VA Medical Center, Portland, OR, USA
| | - Gita Shankar
- Biosciences Division, Pharmaceutical Sciences Laboratories, SRI International, Menlo Park, CA, USA
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24
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Narula AK, Azad CS, Nainwal LM. New dimensions in the field of antimalarial research against malaria resurgence. Eur J Med Chem 2019; 181:111353. [DOI: 10.1016/j.ejmech.2019.05.043] [Citation(s) in RCA: 16] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/05/2018] [Revised: 04/16/2019] [Accepted: 05/15/2019] [Indexed: 12/20/2022]
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25
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Romero AH. Role of Trifluoromethyl Substitution in Design of Antimalarial Quinolones: a Comprehensive Review. Top Curr Chem (Cham) 2019; 377:9. [PMID: 30835005 DOI: 10.1007/s41061-019-0234-7] [Citation(s) in RCA: 14] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/24/2018] [Accepted: 02/22/2019] [Indexed: 10/27/2022]
Abstract
Malaria represents a significant health issue, and novel effective drugs are needed to address parasite resistance that has emerged to the current drug arsenal. The most popular antimalarial drugs are focused on the 7-chloro-4-aminoquinoline [e.g., chloroquine (CQ), amodiaquine (AQ), isoquine (IQ), and tebuquine (TBQ)], artemisinin, and atovaquone systems. Recently, endochin has been used as a platform to design a variety of novel potent and safe antimalarial agents named endochin-like quinolones (ELQs). Also, antimalarial quinolones have been constructed from other quinolones drugs such as ICI-56780 and floxacrine. Trifluoromethyl substitution has provided a significant increase in the antimalarial response of many of the designed ELQs against Plasmodium-resistant strains and for in vivo models. In particular, attachment of a substituted trifluoromethoxy (or trifluoromethyl in some cases) biaryl side chain at 2-, 3-, 4-, or 6-position of the quinolone core has shown to be crucially important to generate selective and potent novel ELQs. Furthermore, 6-chloro and 7-methoxy moieties on the quinolone core have been identified as essential pharmacophores when the trifluoromethoxy biaryl side chain is placed at 2- or 3-position of the quinolone core. Methyl or ethyl ester attached at 3-position is essential when the trifluoromethoxy aryl side chain is attached at 6- or 7-position of the quinolone core. Some promising ELQs are currently under clinical trials, representing an excellent platform for the design of new potent, selective, effective, and safe antimalarial drugs against emergent resistance malarial models.
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Affiliation(s)
- Angel H Romero
- Cátedra de Química General, Facultad de Farmacia, Universidad Central de Venezuela, Los Chaguaramos, Caracas, 1041-A, Venezuela.
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26
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Sánchez-Sánchez R, Vázquez P, Ferre I, Ortega-Mora LM. Treatment of Toxoplasmosis and Neosporosis in Farm Ruminants: State of Knowledge and Future Trends. Curr Top Med Chem 2019; 18:1304-1323. [PMID: 30277158 PMCID: PMC6340160 DOI: 10.2174/1568026618666181002113617] [Citation(s) in RCA: 36] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/01/2018] [Revised: 08/03/2018] [Accepted: 09/13/2018] [Indexed: 12/17/2022]
Abstract
Toxoplasmosis and neosporosis are closely related protozoan diseases that lead to important economic impacts in farm ruminants. Toxoplasma gondii infection mainly causes reproductive failure in small ruminants and is a widespread zoonosis, whereas Neospora caninum infection is one of the most important causes of abortion in cattle worldwide. Vaccination has been considered the most economic measure for controlling these diseases. However, despite vaccine development efforts, only a live-attenuated T. gondii vaccine has been licensed for veterinary use, and no promising vaccines against ne-osporosis have been developed; therefore, vaccine development remains a key goal. Additionally, drug therapy could be a valuable strategy for disease control in farm ruminants, as several drugs that limit T. gondii and N. caninum proliferation and dissemination have been evaluated. This approach may also be relevant to performing an initial drug screening for potential human therapy for zoonotic parasites. Treat-ments can be applied against infections in adult ruminants to minimize the outcomes of a primo-infection or the reactivation of a chronic infection during gestation or in newborn ruminants to avoid infection chronification. In this review, the current status of drug development against toxoplasmosis and neosporo-sis in farm ruminants is presented, and in an effort to promote additional treatment options, prospective drugs that have shown efficacy in vitro and in laboratory animal models of toxoplasmosis and neosporosis are examined
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Affiliation(s)
- Roberto Sánchez-Sánchez
- SALUVET, Animal Health Department, Faculty of Veterinary Sciences, Complutense University of Madrid, Ciudad Universitaria s/n, 28040, Madrid, Spain
| | - Patricia Vázquez
- SALUVET, Animal Health Department, Faculty of Veterinary Sciences, Complutense University of Madrid, Ciudad Universitaria s/n, 28040, Madrid, Spain
| | - Ignacio Ferre
- SALUVET, Animal Health Department, Faculty of Veterinary Sciences, Complutense University of Madrid, Ciudad Universitaria s/n, 28040, Madrid, Spain
| | - Luis Miguel Ortega-Mora
- SALUVET, Animal Health Department, Faculty of Veterinary Sciences, Complutense University of Madrid, Ciudad Universitaria s/n, 28040, Madrid, Spain
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Veale CGL. Unpacking the Pathogen Box-An Open Source Tool for Fighting Neglected Tropical Disease. ChemMedChem 2019; 14:386-453. [PMID: 30614200 DOI: 10.1002/cmdc.201800755] [Citation(s) in RCA: 37] [Impact Index Per Article: 6.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/27/2018] [Indexed: 12/13/2022]
Abstract
The Pathogen Box is a 400-strong collection of drug-like compounds, selected for their potential against several of the world's most important neglected tropical diseases, including trypanosomiasis, leishmaniasis, cryptosporidiosis, toxoplasmosis, filariasis, schistosomiasis, dengue virus and trichuriasis, in addition to malaria and tuberculosis. This library represents an ensemble of numerous successful drug discovery programmes from around the globe, aimed at providing a powerful resource to stimulate open source drug discovery for diseases threatening the most vulnerable communities in the world. This review seeks to provide an in-depth analysis of the literature pertaining to the compounds in the Pathogen Box, including structure-activity relationship highlights, mechanisms of action, related compounds with reported activity against different diseases, and, where appropriate, discussion on the known and putative targets of compounds, thereby providing context and increasing the accessibility of the Pathogen Box to the drug discovery community.
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Affiliation(s)
- Clinton G L Veale
- School of Chemistry and Physics, Pietermaritzburg Campus, University of KwaZulu-Natal, Private Bag X01, Scottsville, 3209, South Africa
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28
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Silva VLM, Silva AMS. Palladium-Catalysed Synthesis and Transformation of Quinolones. Molecules 2019; 24:E228. [PMID: 30634524 PMCID: PMC6359680 DOI: 10.3390/molecules24020228] [Citation(s) in RCA: 19] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/09/2018] [Revised: 12/31/2018] [Accepted: 01/04/2019] [Indexed: 11/16/2022] Open
Abstract
Palladium-catalysed reactions have had a large impact on synthetic organic chemistry and have found many applications in target-oriented synthesis. Their widespread use in organic synthesis is due to the mild conditions associated with the reactions together with their tolerance of a wide range of functional groups. Moreover, these types of reactions allow the rapid construction of complex molecules through multiple bond-forming reactions in a single step, the so-called tandem processes. Pd-catalysed reactions have been applied to the synthesis of a large number of natural products and bioactive compounds, some of them of complex molecular structures. This review article aims to present an overview of the most important Pd-catalysed reactions employed in the synthesis and transformations of quinolin-2(1H)-ones and quinolin-4(1H)-ones. These compounds are widely recognized by their diverse bioactivity, being privileged structures in medicinal chemistry and useful structural moieties for the development of new drug candidates. Furthermore, they hold significant interest due to their host⁻guest chemistry; applications in chemical, biochemical and environmental analyses and use in the development of new synthetic methods. In some cases, the quinolone formation step cannot be ascribed to a claimed Pd-catalysed reaction but this reaction is crucial to get the appropriate substrate for cyclization into the quinolone. Herein we present and discuss different economical, efficient and selective synthetic strategies to access quinolone-type compounds.
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Affiliation(s)
- Vera L M Silva
- Department of Chemistry QOPNA and LAQV-REQUIMTE, University of Aveiro, Campus Universitário de Santiago, 3810-193 Aveiro, Portugal.
| | - Artur M S Silva
- Department of Chemistry QOPNA and LAQV-REQUIMTE, University of Aveiro, Campus Universitário de Santiago, 3810-193 Aveiro, Portugal.
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Anghel N, Balmer V, Müller J, Winzer P, Aguado-Martinez A, Roozbehani M, Pou S, Nilsen A, Riscoe M, Doggett JS, Hemphill A. Endochin-Like Quinolones Exhibit Promising Efficacy Against Neospora Caninum in vitro and in Experimentally Infected Pregnant Mice. Front Vet Sci 2018; 5:285. [PMID: 30510935 PMCID: PMC6252379 DOI: 10.3389/fvets.2018.00285] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/09/2018] [Accepted: 10/26/2018] [Indexed: 12/21/2022] Open
Abstract
We report on the efficacy of selected endochin-like quinolones (ELQs) against N. caninum tachyzoites grown in human foreskin fibroblasts (HFF), and in a pregnant BALB/c mouse model. Fourteen ELQs were screened against transgenic N. caninum tachyzoites expressing β-galactosidase (Nc-βgal). Drugs were added concomitantly to infection and the values for 50% proliferation inhibition (IC50) were determined after 3 days. Three compounds exhibited IC50 values below 0.1 nM, 3 ELQs had IC50s between 0.1 and 1 nM, for 7 compounds values between 1 and 10 nM were noted, and one compound had an IC50 of 22.4 nM. Two compounds, namely ELQ-316 and its prodrug ELQ-334 with IC50s of 0.66 and 3.33 nM, respectively, were previously shown to display promising activities against experimental toxoplasmosis and babesiosis caused by Babesia microti in mice, and were thus further studied. They were assessed in long-term treatment assays by exposure of infected HFF to ELQs at 0.5 μM concentration, starting 3 h after infection and lasting for up to 17 days followed by release of drug pressure. Results showed that the compounds substantially delayed parasite proliferation, but did not exert parasiticidal activities. TEM of drug treated parasites detected distinct alterations within the parasite mitochondria, but not in other parasite organelles. Assessment of safety of ELQ-334 in the pregnant mouse model showed that the compound did not interfere in fertility or pregnancy outcome. In N. caninum infected pregnant mice treated with ELQ-334 at 10 mg/kg/day for 5 days, neonatal mortality (within 2 days post partum) was found in 7 of 44 pups (15.9%), but no postnatal mortality was noted, and vertical transmission was reduced by 49% compared to the placebo group, which exhibited 100% vertical transmission, neonatal mortality in 15 of 34 pups (44%), and postnatal mortality for 18 of the residual 19 pups during the 4 weeks follow-up. These findings encourage more research on the use of ELQs for therapeutic options against N. caninum infection.
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Affiliation(s)
- Nicoleta Anghel
- Vetsuisse Faculty, Institute of Parasitology, University of Bern, Bern, Switzerland
| | - Vreni Balmer
- Vetsuisse Faculty, Institute of Parasitology, University of Bern, Bern, Switzerland
| | - Joachim Müller
- Vetsuisse Faculty, Institute of Parasitology, University of Bern, Bern, Switzerland
| | - Pablo Winzer
- Vetsuisse Faculty, Institute of Parasitology, University of Bern, Bern, Switzerland
| | | | - Mona Roozbehani
- Department of Parasitology, School of Medicine, Iran University of Medical Sciences, Tehran, Iran
| | - Sovitj Pou
- VA Portland Health Care System Research and Development Service, Portland, OR, United States
| | - Aaron Nilsen
- VA Portland Health Care System Research and Development Service, Portland, OR, United States
| | - Michael Riscoe
- VA Portland Health Care System Research and Development Service, Portland, OR, United States
| | - J Stone Doggett
- VA Portland Health Care System Research and Development Service, Portland, OR, United States
| | - Andrew Hemphill
- Vetsuisse Faculty, Institute of Parasitology, University of Bern, Bern, Switzerland
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30
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McConnell EV, Bruzual I, Pou S, Winter R, Dodean RA, Smilkstein MJ, Krollenbrock A, Nilsen A, Zakharov LN, Riscoe MK, Doggett JS. Targeted Structure-Activity Analysis of Endochin-like Quinolones Reveals Potent Qi and Qo Site Inhibitors of Toxoplasma gondii and Plasmodium falciparum Cytochrome bc 1 and Identifies ELQ-400 as a Remarkably Effective Compound against Acute Experimental Toxoplasmosis. ACS Infect Dis 2018; 4:1574-1584. [PMID: 30117728 DOI: 10.1021/acsinfecdis.8b00133] [Citation(s) in RCA: 28] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/24/2023]
Abstract
Cytochrome bc1 inhibitors have been broadly studied as human and veterinary medicines and agricultural fungicides. For the most part, cytochrome bc1 inhibitors compete with ubiquinol at the ubiquinol oxidation (Qo) site or with ubiquinone at the quinone reduction (Qi) site. 4(1 H)-Quinolones with 3-position substituents may inhibit either site based on quinolone ring substituents. 4(1 H)-Quinolones that inhibit the Qi site are highly effective against toxoplasmosis, malaria, and babesiosis and do not inhibit human cytochrome bc1. We tested a series of 4(1 H)-Quinolones against wild-type and drug resistant strains of Toxoplasma gondii and Plasmodium falciparum. These experiments identified very potent compounds that inhibit T. gondii proliferation at picomolar concentrations. The most potent compounds target the Qo site, and for these compounds, an alkyl side chain confers potency against T. gondii greater than that of bulkier side chains. Our experiments also show that substituents on the quinolone ring influenced selectivity between T. gondii and P. falciparum and between Qo and Qi site-mediated activity. Comparison of the parasite cytochrome b sequences identified amino acids that are associated with drug resistance in P. falciparum that exist naturally in wild-type T. gondii. These underlying differences may influence drug susceptibility. Finally, a Qo site active 4(1 H)-quinolone-3-diarylether tested in a murine model of toxoplasmosis was superior to atovaquone, resulting in survival from Type I strain T. gondii infection. These experiments identify highly effective compounds for toxoplasmosis and provide valuable insight into the structure-activity relationship of cytochrome bc1 inhibitors.
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Affiliation(s)
- Erin V. McConnell
- VA Portland Health Care System Research and Development Service, 3710 SW US Veterans Hospital Road, Portland, Oregon 97239, United States
| | - Igor Bruzual
- VA Portland Health Care System Research and Development Service, 3710 SW US Veterans Hospital Road, Portland, Oregon 97239, United States
| | - Sovitj Pou
- VA Portland Health Care System Research and Development Service, 3710 SW US Veterans Hospital Road, Portland, Oregon 97239, United States
| | - Rolf Winter
- VA Portland Health Care System Research and Development Service, 3710 SW US Veterans Hospital Road, Portland, Oregon 97239, United States
| | - Rozalia A. Dodean
- VA Portland Health Care System Research and Development Service, 3710 SW US Veterans Hospital Road, Portland, Oregon 97239, United States
| | - Martin J. Smilkstein
- VA Portland Health Care System Research and Development Service, 3710 SW US Veterans Hospital Road, Portland, Oregon 97239, United States
| | - Alina Krollenbrock
- Oregon Health & Science University Department of Physiology and Pharmacology, 3181 SW Sam Jackson Park Road, Portland, Oregon 97239, United States
| | - Aaron Nilsen
- VA Portland Health Care System Research and Development Service, 3710 SW US Veterans Hospital Road, Portland, Oregon 97239, United States
| | - Lev N. Zakharov
- Department of Chemistry, University of Oregon, 1585 E 13th Avenue, Eugene, Oregon 97403, United States
| | - Michael K. Riscoe
- VA Portland Health Care System Research and Development Service, 3710 SW US Veterans Hospital Road, Portland, Oregon 97239, United States
- Department of Molecular Microbiology & Immunology, Oregon Health & Science University, 3181 SW Sam Jackson Park Road, Portland, Oregon 97239, United States
| | - J. Stone Doggett
- VA Portland Health Care System Research and Development Service, 3710 SW US Veterans Hospital Road, Portland, Oregon 97239, United States
- Division of Infectious Diseases, Oregon Health & Science University Department of Medicine 3181 SW Sam Jackson Park Road, Portland, Oregon 97239, United States
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31
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Poonam, Gupta Y, Gupta N, Singh S, Wu L, Chhikara BS, Rawat M, Rathi B. Multistage inhibitors of the malaria parasite: Emerging hope for chemoprotection and malaria eradication. Med Res Rev 2018; 38:1511-1535. [PMID: 29372568 DOI: 10.1002/med.21486] [Citation(s) in RCA: 20] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/12/2017] [Revised: 12/09/2017] [Accepted: 12/26/2017] [Indexed: 12/13/2022]
Abstract
Over time, several exciting advances have been made in the treatment and prevention of malaria; however, this devastating disease continues to be a major global health problem and affects millions of people every year. Notably, the paucity of new efficient drug molecules and the inevitable drug resistance of the malaria parasite, Plasmodium falciparum, against frontline therapeutics are the foremost struggles facing malaria eradication initiatives. According to the malaria eradication agenda, the discovery of new chemical entities that can destroy the parasite at the liver stage, the asexual blood stage, the gametocyte stage, and the insect ookinete stage of the parasite life cycle (i.e., compounds exhibiting multistage activity) are in high demand, preferably with novel and multiple modes of action. Phenotypic screening of chemical libraries against the malaria parasite is certainly a crucial step toward overcoming these crises. In the last few years, various research groups, including industrial research laboratories, have performed large-scale phenotypic screenings that have identified a wealth of chemical entities active against multiple life stages of the malaria parasite. Vital scientific and technological developments have led to the discovery of multistage inhibitors of the malaria parasite; these compounds, considered highly valuable starting points for subsequent drug discovery and eradication of malaria, are reviewed.
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Affiliation(s)
- Poonam
- Department of Chemistry, Miranda House, University of Delhi, India
| | - Yash Gupta
- National Institute of Malaria Research (ICMR), New Delhi, India
| | - Nikesh Gupta
- Special Centre for Nanosciences, Jawaharlal Nehru University, New Delhi, India
| | - Snigdha Singh
- Laboratory for Translational Chemistry and Drug Discovery, Department of Chemistry, Hansraj College University Enclave, University of Delhi, Delhi, India
| | - Lidong Wu
- Department of Chemistry, Massachusetts Institute of Technology, Cambridge, MA, USA
- Key Laboratory of Control of Quality and Safety for Aquatic Products, Ministry of Agriculture, Chinese Academy of Fishery Sciences, Beijing, China
| | | | - Manmeet Rawat
- Department of Internal Medicine, University of New Mexico School of Medicine, Albuquerque, NM, USA
| | - Brijesh Rathi
- Laboratory for Translational Chemistry and Drug Discovery, Department of Chemistry, Hansraj College University Enclave, University of Delhi, Delhi, India
- Department of Chemistry, Massachusetts Institute of Technology, Cambridge, MA, USA
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32
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Neelarapu R, Maignan JR, Lichorowic CL, Monastyrskyi A, Mutka TS, LaCrue AN, Blake LD, Casandra D, Mashkouri S, Burrows JN, Willis PA, Kyle DE, Manetsch R. Design and Synthesis of Orally Bioavailable Piperazine Substituted 4(1H)-Quinolones with Potent Antimalarial Activity: Structure-Activity and Structure-Property Relationship Studies. J Med Chem 2018; 61:1450-1473. [PMID: 29215279 DOI: 10.1021/acs.jmedchem.7b00738] [Citation(s) in RCA: 27] [Impact Index Per Article: 3.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/29/2023]
Abstract
Malaria deaths have been decreasing over the last 10-15 years, with global mortality rates having fallen by 47% since 2000. While the World Health Organization (WHO) recommends the use of artemisinin-based combination therapies (ACTs) to combat malaria, the emergence of artemisinin resistant strains underscores the need to develop new antimalarial drugs. Recent in vivo efficacy improvements of the historical antimalarial ICI 56,780 have been reported, however, with the poor solubility and rapid development of resistance, this compound requires further optimization. A series of piperazine-containing 4(1H)-quinolones with greatly enhanced solubility were developed utilizing structure-activity relationship (SAR) and structure-property relationship (SPR) studies. Furthermore, promising compounds were chosen for an in vivo scouting assay to narrow selection for testing in an in vivo Thompson test. Finally, two piperazine-containing 4(1H)-quinolones were curative in the conventional Thompson test and also displayed in vivo activity against the liver stages of the parasite.
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Affiliation(s)
- Raghupathi Neelarapu
- Department of Chemistry, University of South Florida , CHE 205, 4202 East Fowler Avenue, Tampa, Florida 33620, United States
| | - Jordany R Maignan
- Department of Chemistry, University of South Florida , CHE 205, 4202 East Fowler Avenue, Tampa, Florida 33620, United States
| | - Cynthia L Lichorowic
- Department of Chemistry and Chemical Biology, Northeastern University , 102 Hurtig Hall, 360 Huntington Avenue, Boston, Massachusetts 02115, United States
| | - Andrii Monastyrskyi
- Department of Chemistry, University of South Florida , CHE 205, 4202 East Fowler Avenue, Tampa, Florida 33620, United States
| | - Tina S Mutka
- Department of Global Health, College of Public Health, University of South Florida , 3720 Spectrum Boulevard, Suite 304, Tampa, Florida 33612, United States
| | - Alexis N LaCrue
- Department of Global Health, College of Public Health, University of South Florida , 3720 Spectrum Boulevard, Suite 304, Tampa, Florida 33612, United States
| | - Lynn D Blake
- Department of Global Health, College of Public Health, University of South Florida , 3720 Spectrum Boulevard, Suite 304, Tampa, Florida 33612, United States
| | - Debora Casandra
- Department of Global Health, College of Public Health, University of South Florida , 3720 Spectrum Boulevard, Suite 304, Tampa, Florida 33612, United States
| | - Sherwin Mashkouri
- Department of Global Health, College of Public Health, University of South Florida , 3720 Spectrum Boulevard, Suite 304, Tampa, Florida 33612, United States
| | - Jeremy N Burrows
- Medicines for Malaria Venture , 20, Route de Pré-Bois, P.O. Box 1826, 1215 Geneva, Switzerland
| | - Paul A Willis
- Medicines for Malaria Venture , 20, Route de Pré-Bois, P.O. Box 1826, 1215 Geneva, Switzerland
| | - Dennis E Kyle
- Department of Global Health, College of Public Health, University of South Florida , 3720 Spectrum Boulevard, Suite 304, Tampa, Florida 33612, United States
| | - Roman Manetsch
- Department of Chemistry and Chemical Biology, Northeastern University , 102 Hurtig Hall, 360 Huntington Avenue, Boston, Massachusetts 02115, United States.,Department of Pharmaceutical Sciences, Northeastern University , 102 Hurtig Hall, 360 Huntington Avenue, Boston, Massachusetts 02115, United States
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33
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Fan YL, Cheng XW, Wu JB, Liu M, Zhang FZ, Xu Z, Feng LS. Antiplasmodial and antimalarial activities of quinolone derivatives: An overview. Eur J Med Chem 2018; 146:1-14. [PMID: 29360043 DOI: 10.1016/j.ejmech.2018.01.039] [Citation(s) in RCA: 72] [Impact Index Per Article: 10.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/02/2017] [Revised: 01/03/2018] [Accepted: 01/12/2018] [Indexed: 10/18/2022]
Abstract
Malaria remains one of the most deadly infectious diseases globally. Considering the growing spread of resistance, development of new and effective antimalarials remains an urgent priority. Quinolones, which are emerged as one of the most important class of antibiotics in the treatment of various bacterial infections, showed potential in vitro antiplasmodial and in vivo antimalarial activities, making them promising candidates for the chemoprophylaxis and treatment of malaria. This review presents the current progresses and applications of quinolone-based derivatives as potential antimalarials to pave the way for the development of new antimalarials.
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Affiliation(s)
- Yi-Lei Fan
- College of Pharmaceutical Science & Green Pharmaceutical Collaborative Innovation Center of Yangtze River Delta Region, Zhejiang University of Technology, Hangzhou, 310014, PR China; Key Laboratory of Drug Prevention and Control Technology of Zhejiang Province, Zhejiang Police College, Hangzhou, PR China
| | - Xiang-Wei Cheng
- Key Laboratory of Drug Prevention and Control Technology of Zhejiang Province, Zhejiang Police College, Hangzhou, PR China
| | - Jian-Bing Wu
- Key Laboratory of Drug Prevention and Control Technology of Zhejiang Province, Zhejiang Police College, Hangzhou, PR China
| | - Min Liu
- College of Pharmaceutical Science & Green Pharmaceutical Collaborative Innovation Center of Yangtze River Delta Region, Zhejiang University of Technology, Hangzhou, 310014, PR China
| | - Feng-Zhi Zhang
- College of Pharmaceutical Science & Green Pharmaceutical Collaborative Innovation Center of Yangtze River Delta Region, Zhejiang University of Technology, Hangzhou, 310014, PR China.
| | - Zhi Xu
- School of Chemistry and Chemical Engineering, Wuhan University of Science and Technology, Wuhan, Hubei, 430081, PR China
| | - Lian-Shun Feng
- Synthetic and Functional Biomolecules Center, Peking University, Beijing, PR China
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34
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Sahani RL, Liu R. Gold‐Catalyzed [4+2] Annulation/Cyclization Cascades of Benzisoxazoles with Propiolate Derivatives to Access Highly Oxygenated Tetrahydroquinolines. Angew Chem Int Ed Engl 2017. [DOI: 10.1002/ange.201707423] [Citation(s) in RCA: 31] [Impact Index Per Article: 3.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/30/2022]
Affiliation(s)
| | - Rai‐Shung Liu
- Department of Chemistry National Tsing-Hua University Hsinchu Taiwan, ROC
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35
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Sahani RL, Liu R. Gold‐Catalyzed [4+2] Annulation/Cyclization Cascades of Benzisoxazoles with Propiolate Derivatives to Access Highly Oxygenated Tetrahydroquinolines. Angew Chem Int Ed Engl 2017; 56:12736-12740. [DOI: 10.1002/anie.201707423] [Citation(s) in RCA: 95] [Impact Index Per Article: 11.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/21/2017] [Indexed: 11/11/2022]
Affiliation(s)
| | - Rai‐Shung Liu
- Department of Chemistry National Tsing-Hua University Hsinchu Taiwan, ROC
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36
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Müller J, Aguado A, Laleu B, Balmer V, Ritler D, Hemphill A. In vitro screening of the open source Pathogen Box identifies novel compounds with profound activities against Neospora caninum. Int J Parasitol 2017; 47:801-809. [PMID: 28751177 DOI: 10.1016/j.ijpara.2017.06.002] [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] [Received: 04/18/2017] [Revised: 06/01/2017] [Accepted: 06/03/2017] [Indexed: 11/25/2022]
Abstract
Neospora caninum is a major cause of abortion in cattle and represents an important veterinary health problem of great economic significance. The Medicines for Malaria Venture (MMV) Pathogen Box, an open-source collection of 400 compounds with proven anti-infective properties against a wide range of pathogens, was screened against a N. caninum beta-galactosidase reporter strain grown in human foreskin fibroblasts. A primary screening carried out at 1µM yielded 40 compounds that were effective against N. caninum tachyzoites. However, 30 of these compounds also affected the viability of the host cells. The 10 remaining compounds exhibited IC50 values between 4 and 43nM. Three compounds with IC50 values below 10nM, namely MMV676602, MMV688762 and MMV671636, were further characterized in vitro in more detail with respect to inhibition of invasion versus intracellular proliferation, and only MMV671636 had an impact on intracellular proliferation of tachyzoites. This was confirmed by transmission electron microscopy, showing that the primary target of MMV671636 was the mitochondrion. MMV671636 treatment of experimentally infected mice significantly reduced the number of animals with lung and brain infection, and these mice also exhibited a significantly reduced titer of antibodies directed against N. caninum antigens. Thus, MMV671636 is a promising starting point for the development of a future neosporosis therapy.
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Affiliation(s)
- Joachim Müller
- Institute for Parasitology, Vetsuisse Faculty, University of Bern, Bern, Switzerland
| | - Adriana Aguado
- Institute for Parasitology, Vetsuisse Faculty, University of Bern, Bern, Switzerland
| | - Benoît Laleu
- Medicines for Malaria Venture (MMV), PO Box 1826, 20, Route de Pré-Bois, 1215 Geneva 15, Switzerland
| | - Vreni Balmer
- Institute for Parasitology, Vetsuisse Faculty, University of Bern, Bern, Switzerland
| | - Dominic Ritler
- Institute for Parasitology, Vetsuisse Faculty, University of Bern, Bern, Switzerland
| | - Andrew Hemphill
- Institute for Parasitology, Vetsuisse Faculty, University of Bern, Bern, Switzerland.
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37
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Namelikonda NK, Monastyrskyi A, Manetsch R. Scalable Multigram Syntheses of Antimalarial 4(1H
)-Quinolones ELQ-300 and P4Q-391. European J Org Chem 2017. [DOI: 10.1002/ejoc.201700326] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/11/2022]
Affiliation(s)
| | - Andrii Monastyrskyi
- Department of Chemistry; University of South Florida; 4202 E Fowler Ave. 33620 Tampa FL USA
| | - Roman Manetsch
- Department of Chemistry; University of South Florida; 4202 E Fowler Ave. 33620 Tampa FL USA
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38
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Presley CC, Du Y, Dalal S, Merino EF, Butler JH, Rakotonandrasana S, Rasamison VE, Cassera MB, Kingston DGI. Isolation, structure elucidation, and synthesis of antiplasmodial quinolones from Crinum firmifolium. Bioorg Med Chem 2017. [PMID: 28648491 DOI: 10.1016/j.bmc.2017.06.017] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/19/2022]
Abstract
Antiplasmodial bioassay guided fractionation of a Madagascar collection of Crinum firmifolium led to the isolation of seven compounds. Five of the seven compounds were determined to be 2-alkylquinolin-4(1H)-ones with varying side chains. Compounds 1 and 4 were determined to be known compounds with reported antiplasmodial activities, while 5 was believed to be a new branched 2-alkylquinolin-4(1H)-one, however, it was isolated in limited quantities and in admixture and therefore was synthesized to confirm its structure as a new antiplasmodial compound. Along with 5, two other new and branched compounds 6 and 7 were synthesized as well. Accompanying the five quinolones were two known compounds 2 and 3 which are inactive against Plasmodium falciparum. The isolation, structure elucidation, total synthesis, and biological evaluation of these compounds are discussed in this article.
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Affiliation(s)
- Christopher C Presley
- Department of Chemistry and Virginia Tech Center for Drug Discovery, M/C 0212, Virginia Tech, Blacksburg, VA 24061, United States
| | - Yongle Du
- Department of Chemistry and Virginia Tech Center for Drug Discovery, M/C 0212, Virginia Tech, Blacksburg, VA 24061, United States
| | - Seema Dalal
- Department of Biochemistry and Virginia Tech Center for Drug Discovery, M/C 0308, Virginia Tech, Blacksburg, VA 24061, United States
| | - Emilio F Merino
- Department of Biochemistry and Molecular Biology, and Center for Tropical and Emerging Global Diseases (CTEGD), University of Georgia, Athens, GA 30602, United States
| | - Joshua H Butler
- Department of Biochemistry and Molecular Biology, and Center for Tropical and Emerging Global Diseases (CTEGD), University of Georgia, Athens, GA 30602, United States
| | - Stéphan Rakotonandrasana
- Centre National d'Application des Recherches Pharmaceutiques, B.P 702, Antananarivo 101, Madagascar
| | - Vincent E Rasamison
- Centre National d'Application des Recherches Pharmaceutiques, B.P 702, Antananarivo 101, Madagascar
| | - Maria B Cassera
- Department of Biochemistry and Molecular Biology, and Center for Tropical and Emerging Global Diseases (CTEGD), University of Georgia, Athens, GA 30602, United States
| | - David G I Kingston
- Department of Chemistry and Virginia Tech Center for Drug Discovery, M/C 0212, Virginia Tech, Blacksburg, VA 24061, United States.
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39
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Naveen B, Ommi NB, Mudiraj A, Mallikarjuna T, Babu PP, Nagarajan R. Total Synthesis of Penicinoline E, Marinamide, Methyl Marinamide and their Antimalarial Activity. ChemistrySelect 2017. [DOI: 10.1002/slct.201700242] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022]
Affiliation(s)
- Badher Naveen
- School of Chemistry; University of Hyderabad; Hyderabad - 500046 India
| | - Naidu Babu Ommi
- Department of Biotechnology & Bioinformatics; School of Life Sciences, University of Hyderabad; Hyderabad - 500046 India
| | - Anwita Mudiraj
- Department of Biotechnology & Bioinformatics; School of Life Sciences, University of Hyderabad; Hyderabad - 500046 India
| | - Thippana Mallikarjuna
- Department of Biotechnology & Bioinformatics; School of Life Sciences, University of Hyderabad; Hyderabad - 500046 India
| | - Phanithi Prakash Babu
- Department of Biotechnology & Bioinformatics; School of Life Sciences, University of Hyderabad; Hyderabad - 500046 India
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40
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Gaillard T, Madamet M, Tsombeng FF, Dormoi J, Pradines B. Antibiotics in malaria therapy: which antibiotics except tetracyclines and macrolides may be used against malaria? Malar J 2016; 15:556. [PMID: 27846898 PMCID: PMC5109779 DOI: 10.1186/s12936-016-1613-y] [Citation(s) in RCA: 33] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/24/2016] [Accepted: 11/10/2016] [Indexed: 01/15/2023] Open
Abstract
Malaria, a parasite vector-borne disease, is one of the most significant health threats in tropical regions, despite the availability of individual chemoprophylaxis. Malaria chemoprophylaxis and chemotherapy remain a major area of research, and new drug molecules are constantly being developed before drug-resistant parasites strains emerge. The use of anti-malarial drugs is challenged by contra-indications, the level of resistance of Plasmodium falciparum in endemic areas, clinical tolerance and financial cost. New therapeutic approaches are currently needed to fight against this disease. Some antibiotics that have shown potential effects on malaria parasite have been recently studied in vitro or in vivo intensively. Two families, tetracyclines and macrolides and their derivatives have been particularly studied in recent years. However, other less well-known have been tested or are being used for malaria treatment. Some of these belong to older families, such as quinolones, co-trimoxazole or fusidic acid, while others are new drug molecules such as tigecycline. These emerging antibiotics could be used to prevent malaria in the future. In this review, the authors overview the use of antibiotics for malaria treatment.
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Affiliation(s)
- Tiphaine Gaillard
- Fédération des Laboratoires, Hôpital d'Instruction des Armées Saint Anne, Toulon, France.,Unité de Parasitologie et d'Entomologie, Département des Maladies Infectieuses, Institut de Recherche Biomédicale des Armées, Marseille, France.,Unité de Recherche sur les Maladies Infectieuses et Tropicales Emergentes, Aix Marseille Université, UM 63, CNRS 7278, IRD 198, Inserm 1095, Marseille, France
| | - Marylin Madamet
- Unité de Parasitologie et d'Entomologie, Département des Maladies Infectieuses, Institut de Recherche Biomédicale des Armées, Marseille, France.,Unité de Recherche sur les Maladies Infectieuses et Tropicales Emergentes, Aix Marseille Université, UM 63, CNRS 7278, IRD 198, Inserm 1095, Marseille, France.,Centre National de Référence du Paludisme, Marseille, France
| | - Francis Foguim Tsombeng
- Unité de Parasitologie et d'Entomologie, Département des Maladies Infectieuses, Institut de Recherche Biomédicale des Armées, Marseille, France.,Unité de Recherche sur les Maladies Infectieuses et Tropicales Emergentes, Aix Marseille Université, UM 63, CNRS 7278, IRD 198, Inserm 1095, Marseille, France
| | - Jérôme Dormoi
- Unité de Parasitologie et d'Entomologie, Département des Maladies Infectieuses, Institut de Recherche Biomédicale des Armées, Marseille, France.,Unité de Recherche sur les Maladies Infectieuses et Tropicales Emergentes, Aix Marseille Université, UM 63, CNRS 7278, IRD 198, Inserm 1095, Marseille, France
| | - Bruno Pradines
- Unité de Parasitologie et d'Entomologie, Département des Maladies Infectieuses, Institut de Recherche Biomédicale des Armées, Marseille, France. .,Unité de Recherche sur les Maladies Infectieuses et Tropicales Emergentes, Aix Marseille Université, UM 63, CNRS 7278, IRD 198, Inserm 1095, Marseille, France. .,Centre National de Référence du Paludisme, Marseille, France.
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41
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Targeting the Cytochrome bc1 Complex of Leishmania Parasites for Discovery of Novel Drugs. Antimicrob Agents Chemother 2016; 60:4972-82. [PMID: 27297476 DOI: 10.1128/aac.00850-16] [Citation(s) in RCA: 25] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/20/2016] [Accepted: 06/02/2016] [Indexed: 11/20/2022] Open
Abstract
Endochin-like quinolones (ELQs) are potent and specific inhibitors of cytochrome bc1 from Plasmodium falciparum and Toxoplasma gondii and show promise for novel antiparasitic drug development. To determine whether the mitochondrial electron transport chain of Leishmania parasites could be targeted similarly for drug development, we investigated the activity of 134 structurally diverse ELQs. A cohort of ELQs was selectively toxic to amastigotes of Leishmania mexicana and L. donovani, with 50% inhibitory concentrations (IC50s) in the low micromolar range, but the structurally similar hydroxynaphthoquinone buparvaquone was by far the most potent inhibitor of electron transport, ATP production, and intracellular amastigote growth. Cytochrome bc1 is thus a promising target for novel antileishmanial drugs, and further improvements on the buparvaquone scaffold are warranted for development of enhanced therapeutics.
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42
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McPhillie M, Zhou Y, El Bissati K, Dubey J, Lorenzi H, Capper M, Lukens AK, Hickman M, Muench S, Verma SK, Weber CR, Wheeler K, Gordon J, Sanders J, Moulton H, Wang K, Kim TK, He Y, Santos T, Woods S, Lee P, Donkin D, Kim E, Fraczek L, Lykins J, Esaa F, Alibana-Clouser F, Dovgin S, Weiss L, Brasseur G, Wirth D, Kent M, Hood L, Meunieur B, Roberts CW, Hasnain SS, Antonyuk SV, Fishwick C, McLeod R. New paradigms for understanding and step changes in treating active and chronic, persistent apicomplexan infections. Sci Rep 2016; 6:29179. [PMID: 27412848 PMCID: PMC4944145 DOI: 10.1038/srep29179] [Citation(s) in RCA: 33] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/01/2016] [Accepted: 05/31/2016] [Indexed: 12/24/2022] Open
Abstract
Toxoplasma gondii, the most common parasitic infection of human brain and eye, persists across lifetimes, can progressively damage sight, and is currently incurable. New, curative medicines are needed urgently. Herein, we develop novel models to facilitate drug development: EGS strain T. gondii forms cysts in vitro that induce oocysts in cats, the gold standard criterion for cysts. These cysts highly express cytochrome b. Using these models, we envisioned, and then created, novel 4-(1H)-quinolone scaffolds that target the cytochrome bc1 complex Qi site, of which, a substituted 5,6,7,8-tetrahydroquinolin-4-one inhibits active infection (IC50, 30 nM) and cysts (IC50, 4 μM) in vitro, and in vivo (25 mg/kg), and drug resistant Plasmodium falciparum (IC50, <30 nM), with clinically relevant synergy. Mutant yeast and co-crystallographic studies demonstrate binding to the bc1 complex Qi site. Our results have direct impact on improving outcomes for those with toxoplasmosis, malaria, and ~2 billion persons chronically infected with encysted bradyzoites.
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Affiliation(s)
| | | | | | | | | | | | - Amanda K Lukens
- Harvard School of Public Health, Boston, Massachusetts, USA
- The Broad Institute, Boston, Massachusetts, USA
| | - Mark Hickman
- Walter Reed Army Institute of Research, Silver Spring, Maryland, USA
| | | | | | | | | | | | | | | | - Kai Wang
- Institute for Systems Biology, Seattle, Washington, USA
| | - Taek-Kyun Kim
- Institute for Systems Biology, Seattle, Washington, USA
| | - Yuqing He
- Institute for Systems Biology, Seattle, Washington, USA
| | - Tatiana Santos
- Albert Einstein College of Medicine, Bronx, New York, USA
| | | | - Patty Lee
- Walter Reed Army Institute of Research, Silver Spring, Maryland, USA
| | - David Donkin
- Walter Reed Army Institute of Research, Silver Spring, Maryland, USA
| | - Eric Kim
- Walter Reed Army Institute of Research, Silver Spring, Maryland, USA
| | | | | | | | | | | | - Louis Weiss
- Albert Einstein College of Medicine, Bronx, New York, USA
| | | | - Dyann Wirth
- Harvard School of Public Health, Boston, Massachusetts, USA
- The Broad Institute, Boston, Massachusetts, USA
| | | | - Leroy Hood
- Institute for Systems Biology, Seattle, Washington, USA
| | - Brigitte Meunieur
- Institute for Integrative Biology of the Cell (12BC), Gif-sur-Yvette, France
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Lawres LA, Garg A, Kumar V, Bruzual I, Forquer IP, Renard I, Virji AZ, Boulard P, Rodriguez EX, Allen AJ, Pou S, Wegmann KW, Winter RW, Nilsen A, Mao J, Preston DA, Belperron AA, Bockenstedt LK, Hinrichs DJ, Riscoe MK, Doggett JS, Ben Mamoun C. Radical cure of experimental babesiosis in immunodeficient mice using a combination of an endochin-like quinolone and atovaquone. J Exp Med 2016; 213:1307-18. [PMID: 27270894 PMCID: PMC4925016 DOI: 10.1084/jem.20151519] [Citation(s) in RCA: 73] [Impact Index Per Article: 8.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/21/2015] [Accepted: 04/25/2016] [Indexed: 01/24/2023] Open
Abstract
Human babesiosis is a tick-borne multisystem disease caused by Babesia species of the apicomplexan phylum. Most clinical cases and fatalities of babesiosis are caused by Babesia microti Current treatment for human babesiosis consists of two drug combinations, atovaquone + azithromycin or quinine + clindamycin. These treatments are associated with adverse side effects and a significant rate of drug failure. Here, we provide evidence for radical cure of experimental babesiosis in immunodeficient mice using a combination of an endochin-like quinolone (ELQ) prodrug and atovaquone. In vivo efficacy studies in mice using ELQ-271, ELQ-316, and the ELQ-316 prodrug, ELQ-334, demonstrated excellent growth inhibitory activity against the parasite, with potency equal to that of orally administered atovaquone at 10 mg/kg. Analysis of recrudescent parasites after ELQ or atovaquone monotherapy identified genetic substitutions in the Qi or Qo sites, respectively, of the cytochrome bc1 complex. Impressively, a combination of ELQ-334 and atovaquone, at doses as low as 5.0 mg/kg each, resulted in complete clearance of the parasite with no recrudescence up to 122 d after discontinuation of therapy. These results will set the stage for future clinical evaluation of ELQ and atovaquone combination therapy for treatment of human babesiosis.
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Affiliation(s)
- Lauren A Lawres
- Department of Internal Medicine, Section of Infectious Diseases, Yale School of Medicine, New Haven, CT 06520
| | - Aprajita Garg
- Department of Internal Medicine, Section of Infectious Diseases, Yale School of Medicine, New Haven, CT 06520
| | - Vidya Kumar
- Department of Internal Medicine, Section of Infectious Diseases, Yale School of Medicine, New Haven, CT 06520
| | - Igor Bruzual
- Veterans Affairs Medical Center, Portland, OR 97239
| | | | - Isaline Renard
- Department of Internal Medicine, Section of Infectious Diseases, Yale School of Medicine, New Haven, CT 06520
| | - Azan Z Virji
- Department of Internal Medicine, Section of Infectious Diseases, Yale School of Medicine, New Haven, CT 06520
| | - Pierre Boulard
- Department of Internal Medicine, Section of Infectious Diseases, Yale School of Medicine, New Haven, CT 06520
| | - Eduardo X Rodriguez
- Department of Internal Medicine, Section of Infectious Diseases, Yale School of Medicine, New Haven, CT 06520
| | - Alexander J Allen
- Department of Internal Medicine, Section of Infectious Diseases, Yale School of Medicine, New Haven, CT 06520
| | - Sovitj Pou
- Veterans Affairs Medical Center, Portland, OR 97239
| | | | | | - Aaron Nilsen
- Veterans Affairs Medical Center, Portland, OR 97239
| | - Jialing Mao
- Department of Internal Medicine, Section of Rheumatology, Yale School of Medicine, New Haven, CT 06520
| | | | - Alexia A Belperron
- Department of Internal Medicine, Section of Rheumatology, Yale School of Medicine, New Haven, CT 06520
| | - Linda K Bockenstedt
- Department of Internal Medicine, Section of Rheumatology, Yale School of Medicine, New Haven, CT 06520
| | | | | | | | - Choukri Ben Mamoun
- Department of Internal Medicine, Section of Infectious Diseases, Yale School of Medicine, New Haven, CT 06520
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44
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Li Y, Shah-Simpson S, Okrah K, Belew AT, Choi J, Caradonna KL, Padmanabhan P, Ndegwa DM, Temanni MR, Corrada Bravo H, El-Sayed NM, Burleigh BA. Transcriptome Remodeling in Trypanosoma cruzi and Human Cells during Intracellular Infection. PLoS Pathog 2016; 12:e1005511. [PMID: 27046031 PMCID: PMC4821583 DOI: 10.1371/journal.ppat.1005511] [Citation(s) in RCA: 116] [Impact Index Per Article: 12.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/18/2015] [Accepted: 02/28/2016] [Indexed: 01/22/2023] Open
Abstract
Intracellular colonization and persistent infection by the kinetoplastid protozoan parasite, Trypanosoma cruzi, underlie the pathogenesis of human Chagas disease. To obtain global insights into the T. cruzi infective process, transcriptome dynamics were simultaneously captured in the parasite and host cells in an infection time course of human fibroblasts. Extensive remodeling of the T. cruzi transcriptome was observed during the early establishment of intracellular infection, coincident with a major developmental transition in the parasite. Contrasting this early response, few additional changes in steady state mRNA levels were detected once mature T. cruzi amastigotes were formed. Our findings suggest that transcriptome remodeling is required to establish a modified template to guide developmental transitions in the parasite, whereas homeostatic functions are regulated independently of transcriptomic changes, similar to that reported in related trypanosomatids. Despite complex mechanisms for regulation of phenotypic expression in T. cruzi, transcriptomic signatures derived from distinct developmental stages mirror known or projected characteristics of T. cruzi biology. Focusing on energy metabolism, we were able to validate predictions forecast in the mRNA expression profiles. We demonstrate measurable differences in the bioenergetic properties of the different mammalian-infective stages of T. cruzi and present additional findings that underscore the importance of mitochondrial electron transport in T. cruzi amastigote growth and survival. Consequences of T. cruzi colonization for the host include dynamic expression of immune response genes and cell cycle regulators with upregulation of host cholesterol and lipid synthesis pathways, which may serve to fuel intracellular T. cruzi growth. Thus, in addition to the biological inferences gained from gene ontology and functional enrichment analysis of differentially expressed genes in parasite and host, our comprehensive, high resolution transcriptomic dataset provides a substantially more detailed interpretation of T. cruzi infection biology and offers a basis for future drug and vaccine discovery efforts. In-depth knowledge of the functional processes governing host colonization and transmission of pathogenic microorganisms is essential for the advancement of effective intervention strategies. This study focuses on Trypanosoma cruzi, the vector-borne protozoan parasite responsible for human Chagas disease and the leading cause of infectious myocarditis worldwide. To gain global insights into the biology of this parasite and its interaction with mammalian host cells, we have exploited a deep-sequencing approach to generate comprehensive, high-resolution transcriptomic maps for mammalian-infective stages of T. cruzi with the simultaneous interrogation of the human host cell transcriptome across an infection time course. We demonstrate that the establishment of intracellular T. cruzi infection in mammalian host cells is accompanied by extensive remodeling of the parasite and host cell transcriptomes. Despite the lack of transcriptional control mechanisms in trypanosomatids, our analyses identified functionally-enriched processes within sets of developmentally-regulated transcripts in T. cruzi that align with known or predicted biological features of the parasite. The novel insights into the biology of intracellular T. cruzi infection and the regulation of amastigote development gained in this study establish a unique foundation for functional network analyses that will be instrumental in providing functional links between parasite dependencies and host functional pathways that have the potential to be exploited for intervention.
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Affiliation(s)
- Yuan Li
- Department of Cell Biology and Molecular Genetics, University of Maryland, College Park, Maryland, United States of America
| | - Sheena Shah-Simpson
- Department of Immunology and Infectious Diseases, Harvard School of Public Health, Boston, Massachusetts, United States of America
| | - Kwame Okrah
- Center for Bioinformatics and Computational Biology, University of Maryland, College Park, Maryland, United States of America
| | - A Trey Belew
- Department of Cell Biology and Molecular Genetics, University of Maryland, College Park, Maryland, United States of America
| | - Jungmin Choi
- Department of Cell Biology and Molecular Genetics, University of Maryland, College Park, Maryland, United States of America
| | - Kacey L Caradonna
- Department of Immunology and Infectious Diseases, Harvard School of Public Health, Boston, Massachusetts, United States of America
| | - Prasad Padmanabhan
- Department of Immunology and Infectious Diseases, Harvard School of Public Health, Boston, Massachusetts, United States of America
| | - David M Ndegwa
- Department of Immunology and Infectious Diseases, Harvard School of Public Health, Boston, Massachusetts, United States of America
| | - M Ramzi Temanni
- Department of Cell Biology and Molecular Genetics, University of Maryland, College Park, Maryland, United States of America
| | - Héctor Corrada Bravo
- Center for Bioinformatics and Computational Biology, University of Maryland, College Park, Maryland, United States of America
| | - Najib M El-Sayed
- Department of Cell Biology and Molecular Genetics, University of Maryland, College Park, Maryland, United States of America.,Center for Bioinformatics and Computational Biology, University of Maryland, College Park, Maryland, United States of America
| | - Barbara A Burleigh
- Department of Immunology and Infectious Diseases, Harvard School of Public Health, Boston, Massachusetts, United States of America
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45
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ELQ-300 prodrugs for enhanced delivery and single-dose cure of malaria. Antimicrob Agents Chemother 2015; 59:5555-60. [PMID: 26124159 DOI: 10.1128/aac.01183-15] [Citation(s) in RCA: 49] [Impact Index Per Article: 4.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/24/2015] [Accepted: 06/20/2015] [Indexed: 11/20/2022] Open
Abstract
ELQ-300 is a preclinical candidate that targets the liver and blood stages of Plasmodium falciparum, as well as the forms that are crucial to transmission of disease: gametocytes, zygotes, and ookinetes. A significant obstacle to the clinical development of ELQ-300 is related to its physicochemical properties. Its relatively poor aqueous solubility and high crystallinity limit absorption to the degree that only low blood concentrations can be achieved following oral dosing. While these low blood concentrations are sufficient for therapy, the levels are too low to establish an acceptable safety margin required by regulatory agencies for clinical development. One way to address the challenging physicochemical properties of ELQ-300 is through the development of prodrugs. Here, we profile ELQ-337, a bioreversible O-linked carbonate ester prodrug of the parent molecule. At the molar equivalent dose of 3 mg/kg of body weight, the delivery of ELQ-300 from ELQ-337 is enhanced by 3- to 4-fold, reaching a maximum concentration of drug in serum (C max) of 5.9 μM by 6 h after oral administration, and unlike ELQ-300 at any dose, ELQ-337 provides single-dose cures of patent malaria infections in mice at low-single-digit milligram per kilogram doses. Our findings show that the prodrug strategy represents a viable approach to overcome the physicochemical limitations of ELQ-300 to deliver the active drug to the bloodstream at concentrations sufficient for safety and toxicology studies, as well as achieving single-dose cures.
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46
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Stickles AM, Ting LM, Morrisey JM, Li Y, Mather MW, Meermeier E, Pershing AM, Forquer IP, Miley GP, Pou S, Winter RW, Hinrichs DJ, Kelly JX, Kim K, Vaidya AB, Riscoe MK, Nilsen A. Inhibition of cytochrome bc1 as a strategy for single-dose, multi-stage antimalarial therapy. Am J Trop Med Hyg 2015; 92:1195-201. [PMID: 25918204 PMCID: PMC4458825 DOI: 10.4269/ajtmh.14-0553] [Citation(s) in RCA: 36] [Impact Index Per Article: 3.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/01/2014] [Accepted: 02/13/2015] [Indexed: 11/07/2022] Open
Abstract
Single-dose therapies for malaria have been proposed as a way to reduce the cost and increase the effectiveness of antimalarial treatment. However, no compound to date has shown single-dose activity against both the blood-stage Plasmodium parasites that cause disease and the liver-stage parasites that initiate malaria infection. Here, we describe a subset of cytochrome bc1 (cyt bc1) inhibitors, including the novel 4(1H)-quinolone ELQ-400, with single-dose activity against liver, blood, and transmission-stage parasites in mouse models of malaria. Although cyt bc1 inhibitors are generally classified as slow-onset antimalarials, we found that a single dose of ELQ-400 rapidly induced stasis in blood-stage parasites, which was associated with a rapid reduction in parasitemia in vivo. ELQ-400 also exhibited a low propensity for drug resistance and was active against atovaquone-resistant P. falciparum strains with point mutations in cyt bc1. Ultimately, ELQ-400 shows that cyt bc1 inhibitors can function as single-dose, blood-stage antimalarials and is the first compound to provide combined treatment, prophylaxis, and transmission blocking activity for malaria after a single oral administration. This remarkable multi-stage efficacy suggests that metabolic therapies, including cyt bc1 inhibitors, may be valuable additions to the collection of single-dose antimalarials in current development.
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Affiliation(s)
- Allison M Stickles
- Departments of Physiology and Pharmacology, Molecular Microbiology and Immunology, Oregon Health and Science University, Portland, Oregon; Departments of Medicine, Pathology, and Microbiology and Immunology, Albert Einstein College of Medicine, Bronx, New York; Department of Microbiology and Immunology, Drexel University College of Medicine, Philadelphia, Pennsylvania; VA Medical Center, Portland, Oregon
| | - Li-Min Ting
- Departments of Physiology and Pharmacology, Molecular Microbiology and Immunology, Oregon Health and Science University, Portland, Oregon; Departments of Medicine, Pathology, and Microbiology and Immunology, Albert Einstein College of Medicine, Bronx, New York; Department of Microbiology and Immunology, Drexel University College of Medicine, Philadelphia, Pennsylvania; VA Medical Center, Portland, Oregon
| | - Joanne M Morrisey
- Departments of Physiology and Pharmacology, Molecular Microbiology and Immunology, Oregon Health and Science University, Portland, Oregon; Departments of Medicine, Pathology, and Microbiology and Immunology, Albert Einstein College of Medicine, Bronx, New York; Department of Microbiology and Immunology, Drexel University College of Medicine, Philadelphia, Pennsylvania; VA Medical Center, Portland, Oregon
| | - Yuexin Li
- Departments of Physiology and Pharmacology, Molecular Microbiology and Immunology, Oregon Health and Science University, Portland, Oregon; Departments of Medicine, Pathology, and Microbiology and Immunology, Albert Einstein College of Medicine, Bronx, New York; Department of Microbiology and Immunology, Drexel University College of Medicine, Philadelphia, Pennsylvania; VA Medical Center, Portland, Oregon
| | - Michael W Mather
- Departments of Physiology and Pharmacology, Molecular Microbiology and Immunology, Oregon Health and Science University, Portland, Oregon; Departments of Medicine, Pathology, and Microbiology and Immunology, Albert Einstein College of Medicine, Bronx, New York; Department of Microbiology and Immunology, Drexel University College of Medicine, Philadelphia, Pennsylvania; VA Medical Center, Portland, Oregon
| | - Erin Meermeier
- Departments of Physiology and Pharmacology, Molecular Microbiology and Immunology, Oregon Health and Science University, Portland, Oregon; Departments of Medicine, Pathology, and Microbiology and Immunology, Albert Einstein College of Medicine, Bronx, New York; Department of Microbiology and Immunology, Drexel University College of Medicine, Philadelphia, Pennsylvania; VA Medical Center, Portland, Oregon
| | - April M Pershing
- Departments of Physiology and Pharmacology, Molecular Microbiology and Immunology, Oregon Health and Science University, Portland, Oregon; Departments of Medicine, Pathology, and Microbiology and Immunology, Albert Einstein College of Medicine, Bronx, New York; Department of Microbiology and Immunology, Drexel University College of Medicine, Philadelphia, Pennsylvania; VA Medical Center, Portland, Oregon
| | - Isaac P Forquer
- Departments of Physiology and Pharmacology, Molecular Microbiology and Immunology, Oregon Health and Science University, Portland, Oregon; Departments of Medicine, Pathology, and Microbiology and Immunology, Albert Einstein College of Medicine, Bronx, New York; Department of Microbiology and Immunology, Drexel University College of Medicine, Philadelphia, Pennsylvania; VA Medical Center, Portland, Oregon
| | - Galen P Miley
- Departments of Physiology and Pharmacology, Molecular Microbiology and Immunology, Oregon Health and Science University, Portland, Oregon; Departments of Medicine, Pathology, and Microbiology and Immunology, Albert Einstein College of Medicine, Bronx, New York; Department of Microbiology and Immunology, Drexel University College of Medicine, Philadelphia, Pennsylvania; VA Medical Center, Portland, Oregon
| | - Sovitj Pou
- Departments of Physiology and Pharmacology, Molecular Microbiology and Immunology, Oregon Health and Science University, Portland, Oregon; Departments of Medicine, Pathology, and Microbiology and Immunology, Albert Einstein College of Medicine, Bronx, New York; Department of Microbiology and Immunology, Drexel University College of Medicine, Philadelphia, Pennsylvania; VA Medical Center, Portland, Oregon
| | - Rolf W Winter
- Departments of Physiology and Pharmacology, Molecular Microbiology and Immunology, Oregon Health and Science University, Portland, Oregon; Departments of Medicine, Pathology, and Microbiology and Immunology, Albert Einstein College of Medicine, Bronx, New York; Department of Microbiology and Immunology, Drexel University College of Medicine, Philadelphia, Pennsylvania; VA Medical Center, Portland, Oregon
| | - David J Hinrichs
- Departments of Physiology and Pharmacology, Molecular Microbiology and Immunology, Oregon Health and Science University, Portland, Oregon; Departments of Medicine, Pathology, and Microbiology and Immunology, Albert Einstein College of Medicine, Bronx, New York; Department of Microbiology and Immunology, Drexel University College of Medicine, Philadelphia, Pennsylvania; VA Medical Center, Portland, Oregon
| | - Jane X Kelly
- Departments of Physiology and Pharmacology, Molecular Microbiology and Immunology, Oregon Health and Science University, Portland, Oregon; Departments of Medicine, Pathology, and Microbiology and Immunology, Albert Einstein College of Medicine, Bronx, New York; Department of Microbiology and Immunology, Drexel University College of Medicine, Philadelphia, Pennsylvania; VA Medical Center, Portland, Oregon
| | - Kami Kim
- Departments of Physiology and Pharmacology, Molecular Microbiology and Immunology, Oregon Health and Science University, Portland, Oregon; Departments of Medicine, Pathology, and Microbiology and Immunology, Albert Einstein College of Medicine, Bronx, New York; Department of Microbiology and Immunology, Drexel University College of Medicine, Philadelphia, Pennsylvania; VA Medical Center, Portland, Oregon
| | - Akhil B Vaidya
- Departments of Physiology and Pharmacology, Molecular Microbiology and Immunology, Oregon Health and Science University, Portland, Oregon; Departments of Medicine, Pathology, and Microbiology and Immunology, Albert Einstein College of Medicine, Bronx, New York; Department of Microbiology and Immunology, Drexel University College of Medicine, Philadelphia, Pennsylvania; VA Medical Center, Portland, Oregon
| | - Michael K Riscoe
- Departments of Physiology and Pharmacology, Molecular Microbiology and Immunology, Oregon Health and Science University, Portland, Oregon; Departments of Medicine, Pathology, and Microbiology and Immunology, Albert Einstein College of Medicine, Bronx, New York; Department of Microbiology and Immunology, Drexel University College of Medicine, Philadelphia, Pennsylvania; VA Medical Center, Portland, Oregon
| | - Aaron Nilsen
- Departments of Physiology and Pharmacology, Molecular Microbiology and Immunology, Oregon Health and Science University, Portland, Oregon; Departments of Medicine, Pathology, and Microbiology and Immunology, Albert Einstein College of Medicine, Bronx, New York; Department of Microbiology and Immunology, Drexel University College of Medicine, Philadelphia, Pennsylvania; VA Medical Center, Portland, Oregon
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47
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Subtle changes in endochin-like quinolone structure alter the site of inhibition within the cytochrome bc1 complex of Plasmodium falciparum. Antimicrob Agents Chemother 2015; 59:1977-82. [PMID: 25605352 DOI: 10.1128/aac.04149-14] [Citation(s) in RCA: 55] [Impact Index Per Article: 5.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022] Open
Abstract
The cytochrome bc1 complex (cyt bc1) is the third component of the mitochondrial electron transport chain and is the target of several potent antimalarial compounds, including the naphthoquinone atovaquone (ATV) and the 4(1H)-quinolone ELQ-300. Mechanistically, cyt bc1 facilitates the transfer of electrons from ubiquinol to cytochrome c and contains both oxidative (Qo) and reductive (Qi) catalytic sites that are amenable to small-molecule inhibition. Although many antimalarial compounds, including ATV, effectively target the Qo site, it has been challenging to design selective Qi site inhibitors with the ability to circumvent clinical ATV resistance, and little is known about how chemical structure contributes to site selectivity within cyt bc1. Here, we used the proposed Qi site inhibitor ELQ-300 to generate a drug-resistant Plasmodium falciparum clone containing an I22L mutation at the Qi region of cyt b. Using this D1 clone and the Y268S Qo mutant strain, P. falciparum Tm90-C2B, we created a structure-activity map of Qi versus Qo site selectivity for a series of endochin-like 4(1H)-quinolones (ELQs). We found that Qi site inhibition was associated with compounds containing 6-position halogens or aryl 3-position side chains, while Qo site inhibition was favored by 5,7-dihalogen groups or 7-position substituents. In addition to identifying ELQ-300 as a preferential Qi site inhibitor, our data suggest that the 4(1H)-quinolone scaffold is compatible with binding to either site of cyt bc1 and that minor chemical changes can influence Qo or Qi site inhibition by the ELQs.
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48
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Charoensutthivarakul S, David Hong W, Leung SC, Gibbons PD, Bedingfield PTP, Nixon GL, Lawrenson AS, Berry NG, Ward SA, Biagini GA, O'Neill PM. 2-Pyridylquinolone
antimalarials with improved antimalarial activity and physicochemical properties. MEDCHEMCOMM 2015. [DOI: 10.1039/c5md00062a] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
Abstract
2-Pyridylquinolones with improved solubility, an improved metabolic stability profile, reduced off-target toxicity and 12 nM Plasmodium falciparum antimalarial activity are described.
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Affiliation(s)
| | - W. David Hong
- Department of Chemistry
- University of Liverpool
- Liverpool
- UK
| | - Suet C. Leung
- Department of Chemistry
- University of Liverpool
- Liverpool
- UK
| | | | | | - Gemma L. Nixon
- Department of Chemistry
- University of Liverpool
- Liverpool
- UK
| | | | - Neil G. Berry
- Department of Chemistry
- University of Liverpool
- Liverpool
- UK
| | - Stephen A. Ward
- Liverpool School of Tropical Medicine
- Pembroke Place
- Liverpool
- UK
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49
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Affiliation(s)
- David S Barnett
- Department of Chemical Biology and Therapeutics, St. Jude Children's Research Hospital , Memphis, Tennessee 38105, United States
| | - R Kiplin Guy
- Department of Chemical Biology and Therapeutics, St. Jude Children's Research Hospital , Memphis, Tennessee 38105, United States
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50
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Cross RM, Flanigan DL, Monastyrskyi A, LaCrue AN, Sáenz FE, Maignan JR, Mutka TS, White KL, Shackleford DM, Bathurst I, Fronczek FR, Wojtas L, Guida WC, Charman SA, Burrows JN, Kyle DE, Manetsch R. Orally bioavailable 6-chloro-7-methoxy-4(1H)-quinolones efficacious against multiple stages of Plasmodium. J Med Chem 2014; 57:8860-79. [PMID: 25148516 PMCID: PMC4234439 DOI: 10.1021/jm500942v] [Citation(s) in RCA: 34] [Impact Index Per Article: 3.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/03/2022]
Abstract
![]()
The continued proliferation
of malaria throughout temperate and
tropical regions of the world has promoted a push for more efficacious
treatments to combat the disease. Unfortunately, more recent remedies
such as artemisinin combination therapies have been rendered less
effective due to developing parasite resistance, and new drugs are
required that target the parasite in the liver to support the disease
elimination efforts. Research was initiated to revisit antimalarials
developed in the 1940s and 1960s that were deemed unsuitable for use
as therapeutic agents as a result of poor understanding of both physicochemical
properties and parasitology. Structure–activity and structure–property
relationship studies were conducted to generate a set of compounds
with the general 6-chloro-7-methoxy-2-methyl-4(1H)-quinolone scaffold which were substituted at the 3-position with
a variety of phenyl moieties possessing various properties. Extensive
physicochemical evaluation of the quinolone series was carried out
to downselect the most promising 4(1H)-quinolones, 7, 62, 66, and 67,
which possessed low-nanomolar EC50 values against W2 and
TM90-C2B as well as improved microsomal stability. Additionally, in
vivo Thompson test results using Plasmodium berghei in mice showed that these 4(1H)-quinolones were
efficacious for the reduction of parasitemia at >99% after 6 days.
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Affiliation(s)
- R Matthew Cross
- Department of Chemistry, University of South Florida , CHE 205, 4202 East Fowler Avenue, Tampa, Florida 33620, United States
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