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Liu R, Li G, Li M, Wang B, Zhang D, Xu L, Zhao L, Liao R, Xu Q, Bei ZC, Song Y. In vitro interaction of naphthoquine with ivermectin, atovaquone, curcumin, and ketotifen in the asexual blood stage of Plasmodium falciparum 3D7. Microbiol Spectr 2024; 12:e0063024. [PMID: 38780257 PMCID: PMC11218538 DOI: 10.1128/spectrum.00630-24] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/25/2024] [Accepted: 04/22/2024] [Indexed: 05/25/2024] Open
Abstract
Naphthoquine is a promising candidate for antimalarial combination therapy. Its combination with artemisinin has demonstrated excellent efficacy in clinical trials conducted across various malaria-endemic areas. A co-formulated combination of naphthoquine and azithromycin has also shown high clinical efficacy for malaria prophylaxis in Southeast Asia. Developing new combination therapies using naphthoquine will provide additional arsenal responses to the growing threat of artemisinin resistance. Furthermore, due to its long half-life, the possible interaction of naphthoquine with other drugs also needs attention. However, studies on its pharmacodynamic interactions with other drugs are still limited. In this study, the in vitro interactions of naphthoquine with ivermectin, atovaquone, curcumin, and ketotifen were evaluated in the asexual stage of Plasmodium falciparum 3D7. By using the combination index analysis and the SYBR Green I-based fluorescence assay, different interaction patterns of selected drugs with naphthoquine were revealed. Curcumin showed a slight but significant synergistic interaction with naphthoquine at lower effect levels, and no antagonism was observed across the full range of effect levels for all tested ratios. Atovaquone showed a potency decline when combined with naphthoquine. For ivermectin, a significant antagonism with naphthoquine was observed at a broad range of effect levels below 75% inhibition, although no significant interaction was observed at higher effect levels. Ketotifen interacted with naphthoquine similar to ivermectin, but significant antagonism was observed for only one tested ratio. These findings should be helpful to the development of new naphthoquine-based combination therapy and the clinically reasonable application of naphthoquine-containing therapies. IMPORTANCE Pharmacodynamic interaction between antimalarials is not only crucial for the development of new antimalarial combination therapies but also important for the appropriate clinical use of antimalarials. The significant synergism between curcumin and naphthoquine observed in this study suggests the potential value for further development of new antimalarial combination therapy. The finding of a decline in atovaquone potency in the presence of naphthoquine alerts to a possible risk of treatment or prophylaxis failure for atovaquone-proguanil following naphthoquine-containing therapies. The observation of antagonism between naphthoquine and ivermectin raised a need for concern about the applicability of naphthoquine-containing therapy in malaria-endemic areas with ivermectin mass drug administration deployed. Considering the role of atovaquone-proguanil as a major alternative when first-line artemisinin-based combination therapy is ineffective and the wide implementation of ivermectin mass drug administration in malaria-endemic countries, the above findings will be important for the appropriate clinical application of antimalarials involving naphthoquine-containing therapies.
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Affiliation(s)
- Ruotong Liu
- Artemisinin Research Center, Guangzhou University of Chinese Medicine, Guangzhou, China
- State Key Laboratory of Pathogen and Biosecurity, Beijing Institute of Microbiology and Epidemiology, Beijing, China
| | - Guoming Li
- Artemisinin Research Center, Guangzhou University of Chinese Medicine, Guangzhou, China
- State Key Laboratory of Pathogen and Biosecurity, Beijing Institute of Microbiology and Epidemiology, Beijing, China
| | - Mei Li
- Artemisinin Research Center, Guangzhou University of Chinese Medicine, Guangzhou, China
- State Key Laboratory of Pathogen and Biosecurity, Beijing Institute of Microbiology and Epidemiology, Beijing, China
| | - Baogang Wang
- State Key Laboratory of Pathogen and Biosecurity, Beijing Institute of Microbiology and Epidemiology, Beijing, China
| | - Dongna Zhang
- State Key Laboratory of Pathogen and Biosecurity, Beijing Institute of Microbiology and Epidemiology, Beijing, China
| | - Likun Xu
- State Key Laboratory of Pathogen and Biosecurity, Beijing Institute of Microbiology and Epidemiology, Beijing, China
| | - Liangliang Zhao
- State Key Laboratory of Pathogen and Biosecurity, Beijing Institute of Microbiology and Epidemiology, Beijing, China
| | - Ruhe Liao
- Artemisinin Research Center, Guangzhou University of Chinese Medicine, Guangzhou, China
- State Key Laboratory of Pathogen and Biosecurity, Beijing Institute of Microbiology and Epidemiology, Beijing, China
| | - Qin Xu
- Artemisinin Research Center, Guangzhou University of Chinese Medicine, Guangzhou, China
| | - Zhu-Chun Bei
- State Key Laboratory of Pathogen and Biosecurity, Beijing Institute of Microbiology and Epidemiology, Beijing, China
| | - Yabin Song
- State Key Laboratory of Pathogen and Biosecurity, Beijing Institute of Microbiology and Epidemiology, Beijing, China
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2
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Annamalai Subramani P, Tipthara P, Kolli SK, Nicholas J, Barnes SJ, Ogbondah MM, Kobylinski KC, Tarning J, Adams JH. Efficacy of ivermectin and its metabolites against Plasmodium falciparum liver stages in primary human hepatocytes. Antimicrob Agents Chemother 2024:e0127223. [PMID: 38904389 DOI: 10.1128/aac.01272-23] [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: 10/03/2023] [Accepted: 06/01/2024] [Indexed: 06/22/2024] Open
Abstract
Ivermectin, a broad-spectrum anti-parasitic drug, has been proposed as a novel vector control tool to reduce malaria transmission by mass drug administration. Ivermectin and some metabolites have mosquito-lethal effect, reducing Anopheles mosquito survival. Ivermectin inhibits liver stage development in a rodent malaria model, but no inhibition was observed in a primate malaria model or in a human malaria challenge trial. In the liver, cytochrome P450 3A4 and 3A5 enzymes metabolize ivermectin, which may impact drug efficacy. Thus, understanding ivermectin metabolism and assessing this impact on Plasmodium liver stage development is critical. Using primary human hepatocytes (PHHs), we characterized ivermectin metabolism and evaluated the efficacy of ivermectin and its primary metabolites M1 (3″-O-demethyl ivermectin) and M3 (4-hydroxymethyl ivermectin) against Plasmodium falciparum liver stages. Two different modes of ivermectin exposure were evaluated: prophylactic mode (days 0-3 post-infection) and curative mode (days 3-5 post-infection). We used two different PHH donors and modes to determine the inhibitory concentration (IC50) of ivermectin, M1, M3, and the known anti-malarial drug pyrimethamine, with IC50 values ranging from 1.391 to 14.44, 9.95-23.71, 4.767-8.384, and 0.9073-5.416 µM, respectively. In our PHH model, ivermectin and metabolites M1 and M3 demonstrated inhibitory activity against P. falciparum liver stages in curative treatment mode (days 3-5) and marginal activity in prophylactic treatment mode (days 0-3). Ivermectin had improved efficacy when co-administered with ketoconazole, a specific inhibitor of cytochrome P450 3A4 enzyme. Further studies should be performed to examine ivermectin liver stage efficacy when co-administered with CYP3A4 inhibitors and anti-malarial drugs to understand the pharmacokinetic and pharmacodynamic drug-drug interactions that enhance efficacy against human malaria parasites in vitro.
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Affiliation(s)
- Pradeep Annamalai Subramani
- Center for Global Health and Interdisciplinary Research, College of Public Health, University of South Florida, Tampa, Florida, USA
| | - Phornpimon Tipthara
- Mahidol Oxford Tropical Medicine Research Unit, Faculty of Tropical Medicine, Mahidol University, Bangkok, Thailand
| | - Surendra Kumar Kolli
- Center for Global Health and Interdisciplinary Research, College of Public Health, University of South Florida, Tampa, Florida, USA
| | - Justin Nicholas
- Center for Global Health and Interdisciplinary Research, College of Public Health, University of South Florida, Tampa, Florida, USA
- Department of Molecular Medicine, Morsani College of Medicine, University of South Florida, Tampa, Florida, USA
| | - Samantha J Barnes
- Center for Global Health and Interdisciplinary Research, College of Public Health, University of South Florida, Tampa, Florida, USA
| | - Madison M Ogbondah
- Center for Global Health and Interdisciplinary Research, College of Public Health, University of South Florida, Tampa, Florida, USA
| | - Kevin C Kobylinski
- Mahidol Oxford Tropical Medicine Research Unit, Faculty of Tropical Medicine, Mahidol University, Bangkok, Thailand
- Department of Entomology, Armed Forces Research Institute of Medical Sciences, Bangkok, Thailand
| | - Joel Tarning
- Mahidol Oxford Tropical Medicine Research Unit, Faculty of Tropical Medicine, Mahidol University, Bangkok, Thailand
- Centre for Tropical Medicine and Global Health, Nuffield Department of Clinical Medicine, University of Oxford, Oxford, United Kingdom
| | - John H Adams
- Center for Global Health and Interdisciplinary Research, College of Public Health, University of South Florida, Tampa, Florida, USA
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3
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Vanachayangkul P, Kodchakorn C, Ta-Aksorn W, Im-Erbsin R, Tungtaeng A, Tipthara P, Tarning J, Lugo-Roman LA, Wojnarski M, Vesely BA, Kobylinski KC. Safety, pharmacokinetics, and potential neurological interactions of ivermectin, tafenoquine, and chloroquine in Rhesus macaques. Antimicrob Agents Chemother 2024:e0018124. [PMID: 38742896 DOI: 10.1128/aac.00181-24] [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: 02/01/2024] [Accepted: 04/19/2024] [Indexed: 05/16/2024] Open
Abstract
Ivermectin (IVM) could be used for malaria control as treated individuals are lethal to blood-feeding Anopheles, resulting in reduced transmission. Tafenoquine (TQ) is used to clear the liver reservoir of Plasmodium vivax and as a prophylactic treatment in high-risk populations. It has been suggested to use ivermectin and tafenoquine in combination, but the safety of these drugs in combination has not been evaluated. Early derivatives of 8-aminoquinolones (8-AQ) were neurotoxic, and ivermectin is an inhibitor of the P-glycoprotein (P-gp) blood brain barrier (BBB) transporter. Thus, there is concern that co-administration of these drugs could be neurotoxic. This study aimed to evaluate the safety and pharmacokinetic interaction of tafenoquine, ivermectin, and chloroquine (CQ) in Rhesus macaques. No clinical, biochemistry, or hematological outcomes of concern were observed. The Cambridge Neuropsychological Test Automated Battery (CANTAB) was employed to assess potential neurological deficits following drug administration. Some impairment was observed with tafenoquine alone and in the same monkeys with subsequent co-administrations. Co-administration of chloroquine and tafenoquine resulted in increased plasma exposure to tafenoquine. Urine concentrations of the 5,6 orthoquinone TQ metabolite were increased with co-administration of tafenoquine and ivermectin. There was an increase in ivermectin plasma exposure when co-administered with chloroquine. No interaction of tafenoquine on ivermectin was observed in vitro. Chloroquine and trace levels of ivermectin, but not tafenoquine, were observed in the cerebrospinal fluid. The 3''-O-demethyl ivermectin metabolite was observed in macaque plasma but not in urine or cerebrospinal fluid. Overall, the combination of ivermectin, tafenoquine, and chloroquine did not have clinical, neurological, or pharmacological interactions of concern in macaques; therefore, this combination could be considered for evaluation in human trials.
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Affiliation(s)
- Pattaraporn Vanachayangkul
- Department of Bacterial and Parasitic Diseases, Armed Forces Research Institute of Medical Sciences, Bangkok, Thailand
| | - Chanikarn Kodchakorn
- Department of Bacterial and Parasitic Diseases, Armed Forces Research Institute of Medical Sciences, Bangkok, Thailand
| | - Winita Ta-Aksorn
- Department of Bacterial and Parasitic Diseases, Armed Forces Research Institute of Medical Sciences, Bangkok, Thailand
| | - Rawiwan Im-Erbsin
- Department of Veterinary Medicine, Armed Forces Research Institute of Medical Sciences, Bangkok, Thailand
| | - Anchalee Tungtaeng
- Department of Veterinary Medicine, Armed Forces Research Institute of Medical Sciences, Bangkok, Thailand
| | - Phornpimon Tipthara
- Mahidol Oxford Tropical Medicine Research Unit, Mahidol University, Bangkok, Thailand
| | - Joel Tarning
- Mahidol Oxford Tropical Medicine Research Unit, Mahidol University, Bangkok, Thailand
- Centre for Tropical Medicine and Global Health, Nuffield Department of Clinical Medicine, University of Oxford, Oxford, United Kingdom
| | - Luis A Lugo-Roman
- Department of Veterinary Medicine, Armed Forces Research Institute of Medical Sciences, Bangkok, Thailand
| | - Mariusz Wojnarski
- Department of Bacterial and Parasitic Diseases, Armed Forces Research Institute of Medical Sciences, Bangkok, Thailand
| | - Brian A Vesely
- Department of Bacterial and Parasitic Diseases, Armed Forces Research Institute of Medical Sciences, Bangkok, Thailand
| | - Kevin C Kobylinski
- Mahidol Oxford Tropical Medicine Research Unit, Mahidol University, Bangkok, Thailand
- Department of Entomology, Armed Forces Research Institute of Medical Sciences, Bangkok, Thailand
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4
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Pottenger AE, Roy D, Srinivasan S, Chavas TEJ, Vlaskin V, Ho DK, Livingston VC, Maktabi M, Lin H, Zhang J, Pybus B, Kudyba K, Roth A, Senter P, Tyson G, Huber HE, Wesche D, Rochford R, Burke PA, Stayton PS. Liver-targeted polymeric prodrugs delivered subcutaneously improve tafenoquine therapeutic window for malaria radical cure. SCIENCE ADVANCES 2024; 10:eadk4492. [PMID: 38640243 PMCID: PMC11029812 DOI: 10.1126/sciadv.adk4492] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/05/2023] [Accepted: 03/19/2024] [Indexed: 04/21/2024]
Abstract
Approximately 3.3 billion people live with the threat of Plasmodium vivax malaria. Infection can result in liver-localized hypnozoites, which when reactivated cause relapsing malaria. This work demonstrates that an enzyme-cleavable polymeric prodrug of tafenoquine addresses key requirements for a mass administration, eradication campaign: excellent subcutaneous bioavailability, complete parasite control after a single dose, improved therapeutic window compared to the parent oral drug, and low cost of goods sold (COGS) at less than $1.50 per dose. Liver targeting and subcutaneous dosing resulted in improved liver:plasma exposure profiles, with increased efficacy and reduced glucose 6-phosphate dehydrogenase-dependent hemotoxicity in validated preclinical models. A COGS and manufacturability analysis demonstrated global scalability, affordability, and the ability to redesign this fully synthetic polymeric prodrug specifically to increase global equity and access. Together, this polymer prodrug platform is a candidate for evaluation in human patients and shows potential for P. vivax eradication campaigns.
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Affiliation(s)
- Ayumi E. Pottenger
- Department of Bioengineering, University of Washington, Seattle, WA 98195, USA
| | - Debashish Roy
- Department of Bioengineering, University of Washington, Seattle, WA 98195, USA
| | - Selvi Srinivasan
- Department of Bioengineering, University of Washington, Seattle, WA 98195, USA
| | - Thomas E. J. Chavas
- Department of Bioengineering, University of Washington, Seattle, WA 98195, USA
| | - Vladmir Vlaskin
- Department of Bioengineering, University of Washington, Seattle, WA 98195, USA
| | - Duy-Khiet Ho
- Department of Bioengineering, University of Washington, Seattle, WA 98195, USA
| | | | - Mahdi Maktabi
- Department of Immunology and Microbiology, University of Colorado Anschutz School of Medicine, Aurora, CO 80045, USA
| | - Hsiuling Lin
- Department of Drug Discovery, Experimental Therapeutics Branch, Walter Reed Army Institute of Research, Silver Spring, MD 20910, USA
| | - Jing Zhang
- Department of Drug Discovery, Experimental Therapeutics Branch, Walter Reed Army Institute of Research, Silver Spring, MD 20910, USA
| | - Brandon Pybus
- Department of Drug Discovery, Experimental Therapeutics Branch, Walter Reed Army Institute of Research, Silver Spring, MD 20910, USA
| | - Karl Kudyba
- Department of Drug Discovery, Experimental Therapeutics Branch, Walter Reed Army Institute of Research, Silver Spring, MD 20910, USA
| | - Alison Roth
- Department of Drug Discovery, Experimental Therapeutics Branch, Walter Reed Army Institute of Research, Silver Spring, MD 20910, USA
| | | | - George Tyson
- George Tyson Consulting, Los Altos Hills, CA 94022, USA
- Department of Chemical and Biomolecular Engineering, University of California, Berkeley, Berkeley, CA 94720, USA
| | - Hans E. Huber
- BioTD Strategies LLC, 213 Abbey Ln., Lansdale, PA 19446, USA
| | | | - Rosemary Rochford
- Department of Immunology and Microbiology, University of Colorado Anschutz School of Medicine, Aurora, CO 80045, USA
| | - Paul A. Burke
- Department of Bioengineering, University of Washington, Seattle, WA 98195, USA
- Burke Bioventures LLC, 1 Broadway 14th Floor, Cambridge, MA 02142, USA
| | - Patrick S. Stayton
- Department of Bioengineering, University of Washington, Seattle, WA 98195, USA
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5
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Rosado-Quiñones AM, Colón-Lorenzo EE, Pala ZR, Bosch J, Kudyba K, Kudyba H, Leed SE, Roncal N, Baerga-Ortiz A, Roche-Lima A, Gerena Y, Fidock DA, Roth A, Vega-Rodríguez J, Serrano AE. Novel hydrazone compounds with broad-spectrum antiplasmodial activity and synergistic interactions with antimalarial drugs. Antimicrob Agents Chemother 2024:e0164323. [PMID: 38639491 DOI: 10.1128/aac.01643-23] [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: 12/14/2023] [Accepted: 03/20/2024] [Indexed: 04/20/2024] Open
Abstract
The development of novel antiplasmodial compounds with broad-spectrum activity against different stages of Plasmodium parasites is crucial to prevent malaria disease and parasite transmission. This study evaluated the antiplasmodial activity of seven novel hydrazone compounds (referred to as CB compounds: CB-27, CB-41, CB-50, CB-53, CB-58, CB-59, and CB-61) against multiple stages of Plasmodium parasites. All CB compounds inhibited blood stage proliferation of drug-resistant or sensitive strains of Plasmodium falciparum in the low micromolar to nanomolar range. Interestingly, CB-41 exhibited prophylactic activity against hypnozoites and liver schizonts in Plasmodium cynomolgi, a primate model for Plasmodium vivax. Four CB compounds (CB-27, CB-41, CB-53, and CB-61) inhibited P. falciparum oocyst formation in mosquitoes, and five CB compounds (CB-27, CB-41, CB-53, CB-58, and CB-61) hindered the in vitro development of Plasmodium berghei ookinetes. The CB compounds did not inhibit the activation of P. berghei female and male gametocytes in vitro. Isobologram assays demonstrated synergistic interactions between CB-61 and the FDA-approved antimalarial drugs, clindamycin and halofantrine. Testing of six CB compounds showed no inhibition of Plasmodium glutathione S-transferase as a putative target and no cytotoxicity in HepG2 liver cells. CB compounds are promising candidates for further development as antimalarial drugs against multidrug-resistant parasites, which could also prevent malaria transmission.
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Affiliation(s)
- Angélica M Rosado-Quiñones
- Department of Microbiology and Medical Zoology, University of Puerto Rico School of Medicine, San Juan, Puerto Rico
| | - Emilee E Colón-Lorenzo
- Department of Microbiology and Medical Zoology, University of Puerto Rico School of Medicine, San Juan, Puerto Rico
| | - Zarna Rajeshkumar Pala
- Laboratory of Malaria and Vector Research, National Institute of Allergy and Infectious Diseases, National Institutes of Health, Rockville, Maryland, USA
| | - Jürgen Bosch
- Center for Global Health and Diseases, Case Western Reserve University, Cleveland, Ohio, USA
- InterRayBio, LLC, Cleveland, Ohio, USA
| | - Karl Kudyba
- Department of Drug Discovery, Experimental Therapeutics Branch, Walter Reed Army Institute of Research, Silver Spring, Maryland, USA
| | - Heather Kudyba
- Laboratory of Malaria and Vector Research, National Institute of Allergy and Infectious Diseases, National Institutes of Health, Rockville, Maryland, USA
| | - Susan E Leed
- Department of Drug Discovery, Experimental Therapeutics Branch, Walter Reed Army Institute of Research, Silver Spring, Maryland, USA
| | - Norma Roncal
- Department of Drug Discovery, Experimental Therapeutics Branch, Walter Reed Army Institute of Research, Silver Spring, Maryland, USA
| | - Abel Baerga-Ortiz
- Department of Biochemistry, University of Puerto Rico School of Medicine, San Juan, Puerto Rico
| | - Abiel Roche-Lima
- RCMI Program, Medical Science Campus, University of Puerto Rico, San Juan, Puerto Rico
| | - Yamil Gerena
- Department of Pharmacology and Toxicology, University of Puerto Rico School of Medicine, San Juan, Puerto Rico
| | - David A Fidock
- Department of Microbiology and Immunology, Columbia University, New York, New York, USA
- Division of Infectious Diseases, Department of Medicine, Center for Malaria Therapeutics and Antimicrobial Resistance, Columbia University Medical Center, New York, New York, USA
| | - Alison Roth
- Department of Drug Discovery, Experimental Therapeutics Branch, Walter Reed Army Institute of Research, Silver Spring, Maryland, USA
| | - Joel Vega-Rodríguez
- Laboratory of Malaria and Vector Research, National Institute of Allergy and Infectious Diseases, National Institutes of Health, Rockville, Maryland, USA
| | - Adelfa E Serrano
- Department of Microbiology and Medical Zoology, University of Puerto Rico School of Medicine, San Juan, Puerto Rico
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6
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Hsu HC, Li D, Zhan W, Ye J, Liu YJ, Leung A, Qin J, Crespo B, Gamo FJ, Zhang H, Cui L, Roth A, Kirkman LA, Li H, Lin G. Structures revealing mechanisms of resistance and collateral sensitivity of Plasmodium falciparum to proteasome inhibitors. Nat Commun 2023; 14:8302. [PMID: 38097652 PMCID: PMC10721928 DOI: 10.1038/s41467-023-44077-2] [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: 05/30/2023] [Accepted: 11/29/2023] [Indexed: 12/17/2023] Open
Abstract
The proteasome of the malaria parasite Plasmodium falciparum (Pf20S) is an advantageous drug target because its inhibition kills P. falciparum in multiple stages of its life cycle and synergizes with artemisinins. We recently developed a macrocyclic peptide, TDI-8304, that is highly selective for Pf20S over human proteasomes and is potent in vitro and in vivo against P. falciparum. A mutation in the Pf20S β6 subunit, A117D, confers resistance to TDI-8304, yet enhances both enzyme inhibition and anti-parasite activity of a tripeptide vinyl sulfone β2 inhibitor, WLW-vs. Here we present the high-resolution cryo-EM structures of Pf20S with TDI-8304, of human constitutive proteasome with TDI-8304, and of Pf20Sβ6A117D with WLW-vs that give insights into the species selectivity of TDI-8304, resistance to it, and the collateral sensitivity associated with resistance, including that TDI-8304 binds β2 and β5 in wild type Pf20S as well as WLW-vs binds β2 and β5 in Pf20Sβ6A117D. We further show that TDI-8304 kills P. falciparum as quickly as chloroquine and artemisinin and is active against P. cynomolgi at the liver stage. This increases interest in using these structures to facilitate the development of Pf20S inhibitors that target multiple proteasome subunits and limit the emergence of resistance.
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Affiliation(s)
- Hao-Chi Hsu
- Department of Structural Biology, Van Andel Institute, 333 Bostwick Ave NE, Grand Rapids, MI, 49503, USA
| | - Daqiang Li
- Department of Microbiology & Immunology, Weill Cornell Medicine, 1300 York Avenue, New York, NY, 10065, USA
| | - Wenhu Zhan
- Department of Microbiology & Immunology, Weill Cornell Medicine, 1300 York Avenue, New York, NY, 10065, USA
| | - Jianxiang Ye
- Department of Microbiology & Immunology, Weill Cornell Medicine, 1300 York Avenue, New York, NY, 10065, USA
| | - Yi Jing Liu
- Division of Infectious Diseases, Department of Medicine, Weill Cornell Medicine, 1300 York Avenue, New York, NY, 10065, USA
| | - Annie Leung
- Division of Infectious Diseases, Department of Medicine, Weill Cornell Medicine, 1300 York Avenue, New York, NY, 10065, USA
| | - Junling Qin
- Department of Internal Medicine, Morsani College of Medicine, University of South Florida, Tampa, FL, 33612, USA
| | - Benigno Crespo
- Global Health Medicines R&D, GlaxoSmithKline, Severo Ochoa 2, 28760, Tres Cantos, Madrid, Spain
| | - Francisco-Javier Gamo
- Global Health Medicines R&D, GlaxoSmithKline, Severo Ochoa 2, 28760, Tres Cantos, Madrid, Spain
| | - Hao Zhang
- Department of Microbiology & Immunology, Weill Cornell Medicine, 1300 York Avenue, New York, NY, 10065, USA
| | - Liwang Cui
- Department of Internal Medicine, Morsani College of Medicine, University of South Florida, Tampa, FL, 33612, USA
- Center for Global Health and Infectious Diseases Research, College of Public Health, University of South Florida, Tampa, Florida, USA
| | - Alison Roth
- Department of Drug Discovery, Experimental Therapeutics Branch, The Walter Reed Army Institute of Research, 503 Robert Grant Ave., Silver Spring, 20910, MD, USA
| | - Laura A Kirkman
- Department of Microbiology & Immunology, Weill Cornell Medicine, 1300 York Avenue, New York, NY, 10065, USA
- Division of Infectious Diseases, Department of Medicine, Weill Cornell Medicine, 1300 York Avenue, New York, NY, 10065, USA
| | - Huilin Li
- Department of Structural Biology, Van Andel Institute, 333 Bostwick Ave NE, Grand Rapids, MI, 49503, USA.
| | - Gang Lin
- Department of Microbiology & Immunology, Weill Cornell Medicine, 1300 York Avenue, New York, NY, 10065, USA.
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7
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Yipsirimetee A, Tipthara P, Hanboonkunupakarn B, Tripura R, Lek D, Kümpornsin K, Lee MCS, Sattabongkot J, Dondorp AM, White NJ, Kobylinski KC, Tarning J, Chotivanich K. Activity of Ivermectin and Its Metabolites against Asexual Blood Stage Plasmodium falciparum and Its Interactions with Antimalarial Drugs. Antimicrob Agents Chemother 2023; 67:e0173022. [PMID: 37338381 PMCID: PMC10368210 DOI: 10.1128/aac.01730-22] [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: 12/29/2022] [Accepted: 05/12/2023] [Indexed: 06/21/2023] Open
Abstract
Ivermectin is an endectocide used widely to treat a variety of internal and external parasites. Field trials of ivermectin mass drug administration for malaria transmission control have demonstrated a reduction of Anopheles mosquito survival and human malaria incidence. Ivermectin will mostly be deployed together with artemisinin-based combination therapies (ACT), the first-line treatment of falciparum malaria. It has not been well established if ivermectin has activity against asexual stage Plasmodium falciparum or if it interacts with the parasiticidal activity of other antimalarial drugs. This study evaluated antimalarial activity of ivermectin and its metabolites in artemisinin-sensitive and artemisinin-resistant P. falciparum isolates and assessed in vitro drug-drug interaction with artemisinins and its partner drugs. The concentration of ivermectin causing half of the maximum inhibitory activity (IC50) on parasite survival was 0.81 μM with no significant difference between artemisinin-sensitive and artemisinin-resistant isolates (P = 0.574). The ivermectin metabolites were 2-fold to 4-fold less active than the ivermectin parent compound (P < 0.001). Potential pharmacodynamic drug-drug interactions of ivermectin with artemisinins, ACT-partner drugs, and atovaquone were studied in vitro using mixture assays providing isobolograms and derived fractional inhibitory concentrations. There were no synergistic or antagonistic pharmacodynamic interactions when combining ivermectin and antimalarial drugs. In conclusion, ivermectin does not have clinically relevant activity against the asexual blood stages of P. falciparum. It also does not affect the in vitro antimalarial activity of artemisinins or ACT-partner drugs against asexual blood stages of P. falciparum.
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Affiliation(s)
- Achaporn Yipsirimetee
- Department of Clinical Tropical Medicine, Faculty of Tropical Medicine, Mahidol University, Bangkok, Thailand
| | - Phornpimon Tipthara
- Mahidol Oxford Tropical Medicine Research Unit, Faculty of Tropical Medicine, Mahidol University, Bangkok, Thailand
| | - Borimas Hanboonkunupakarn
- Department of Clinical Tropical Medicine, Faculty of Tropical Medicine, Mahidol University, Bangkok, Thailand
- Mahidol Oxford Tropical Medicine Research Unit, Faculty of Tropical Medicine, Mahidol University, Bangkok, Thailand
| | - Rupam Tripura
- Mahidol Oxford Tropical Medicine Research Unit, Faculty of Tropical Medicine, Mahidol University, Bangkok, Thailand
- Centre for Tropical Medicine and Global Health, Nuffield Department of Medicine, University of Oxford, Oxford, United Kingdom
| | - Dysoley Lek
- National Center for Parasitology, Entomology and Malaria Control, Phnom Penh, Cambodia
| | - Krittikorn Kümpornsin
- Wellcome Sanger Institute, Wellcome Genome Campus, Hinxton, United Kingdom
- Calibr, Division of the Scripps Research Institute, La Jolla, California, USA
| | - Marcus C. S. Lee
- Wellcome Sanger Institute, Wellcome Genome Campus, Hinxton, United Kingdom
| | - Jetsumon Sattabongkot
- Mahidol Vivax Research Unit, Faculty of Tropical Medicine, Mahidol University, Bangkok, Thailand
| | - Arjen M. Dondorp
- Mahidol Oxford Tropical Medicine Research Unit, Faculty of Tropical Medicine, Mahidol University, Bangkok, Thailand
- Centre for Tropical Medicine and Global Health, Nuffield Department of Medicine, University of Oxford, Oxford, United Kingdom
| | - Nicholas J. White
- Mahidol Oxford Tropical Medicine Research Unit, Faculty of Tropical Medicine, Mahidol University, Bangkok, Thailand
- Centre for Tropical Medicine and Global Health, Nuffield Department of Medicine, University of Oxford, Oxford, United Kingdom
| | - Kevin C. Kobylinski
- Mahidol Oxford Tropical Medicine Research Unit, Faculty of Tropical Medicine, Mahidol University, Bangkok, Thailand
- Department of Entomology, Armed Forces Research Institute of Medical Sciences, Bangkok, Thailand
| | - Joel Tarning
- Mahidol Oxford Tropical Medicine Research Unit, Faculty of Tropical Medicine, Mahidol University, Bangkok, Thailand
- Centre for Tropical Medicine and Global Health, Nuffield Department of Medicine, University of Oxford, Oxford, United Kingdom
| | - Kesinee Chotivanich
- Department of Clinical Tropical Medicine, Faculty of Tropical Medicine, Mahidol University, Bangkok, Thailand
- Mahidol Oxford Tropical Medicine Research Unit, Faculty of Tropical Medicine, Mahidol University, Bangkok, Thailand
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8
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Plasmodium cynomolgi in humans: current knowledge and future directions of an emerging zoonotic malaria parasite. Infection 2022; 51:623-640. [PMID: 36401673 PMCID: PMC9676733 DOI: 10.1007/s15010-022-01952-2] [Citation(s) in RCA: 8] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/15/2022] [Accepted: 11/01/2022] [Indexed: 11/21/2022]
Abstract
Plasmodium cynomolgi (Pcy), a simian malaria parasite, is a recent perfect example of emerging zoonotic transfer in human. This review summarizes the current knowledge on the epidemiology of natural Pcy infections in humans, mosquitoes and monkeys, along with its biological, clinical and drug sensitivity patterns. Knowledge gaps and further studies on Pcy in humans are also discussed. This parasite currently seems to be geographically limited in South-East Asia (SEA) with a global prevalence in human ranging from 0 to 1.4%. The Pcy infections were reported in local SEA populations and European travelers, and range from asymptomatic carriage to mild/moderate attacks with no evidence of pathognomonic clinical and laboratory patterns but with Pcy strain-shaped clinical differences. Geographical distribution and competence of suitable mosquito vectors and non-primate hosts, globalization, climate change, and increased intrusion of humans into the habitat of monkeys are key determinants to emergence of Pcy parasites in humans, along with its expansion outside SEA. Sensitization/information campaigns coupled with training and assessment sessions of microscopists and clinicians on Pcy are greatly needed to improve data on the epidemiology and management of human Pcy infection. There is a need for development of sensitive and specific molecular tools for individual diagnosis and epidemiological studies. The development of safe and efficient anti-hypnozoite drugs is the main therapeutic challenge for controlling human relapsing malaria parasites. Experience gained from P. knowlesi malaria, development of integrated measures and strategies—ideally with components related to human, monkeys, mosquito vectors, and environment—could be very helpful to prevent emergence of Pcy malaria in humans through disruption of transmission chain from monkeys to humans and ultimately contain its expansion in SEA and potential outbreaks in a context of malaria elimination.
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9
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Valenciano AL, Gomez-Lorenzo MG, Vega-Rodríguez J, Adams JH, Roth A. In vitro models for human malaria: targeting the liver stage. Trends Parasitol 2022; 38:758-774. [PMID: 35780012 PMCID: PMC9378454 DOI: 10.1016/j.pt.2022.05.014] [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: 02/21/2022] [Revised: 05/27/2022] [Accepted: 05/27/2022] [Indexed: 11/16/2022]
Abstract
The Plasmodium liver stage represents a vulnerable therapeutic target to prevent disease progression as the parasite resides in the liver before clinical representation caused by intraerythrocytic development. However, most antimalarial drugs target the blood stage of the parasite's life cycle, and the few drugs that target the liver stage are lethal to patients with a glucose-6-phosphate dehydrogenase deficiency. Furthermore, implementation of in vitro liver models to study and develop novel therapeutics against the liver stage of human Plasmodium species remains challenging. In this review, we focus on the progression of in vitro liver models developed for human Plasmodium spp. parasites, provide a brief review on important assay requirements, and lastly present recommendations to improve models to enhance the discovery process of novel preclinical therapeutics.
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Affiliation(s)
- Ana Lisa Valenciano
- Center for Global Health and Infectious Diseases, College of Public Health, University of South Florida, Tampa, FL 33612, USA; Global Health Medicines R&D, GlaxoSmithKline, Severo Ochoa 2, Tres Cantos 28760, Madrid, Spain
| | - Maria G Gomez-Lorenzo
- Global Health Medicines R&D, GlaxoSmithKline, Severo Ochoa 2, Tres Cantos 28760, Madrid, Spain
| | - Joel Vega-Rodríguez
- Laboratory of Malaria and Vector Research, National Institute of Allergy and Infectious Diseases, National Institutes of Health, Rockville, MD 20852, USA
| | - John H Adams
- Center for Global Health and Infectious Diseases, College of Public Health, University of South Florida, Tampa, FL 33612, USA
| | - Alison Roth
- Department of Drug Discovery, Experimental Therapeutics Branch, Walter Reed Army Institute of Research, Silver Spring, MD 20910, USA.
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10
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Kanai M, Hagenah LM, Ashley EA, Chibale K, Fidock DA. Keystone Malaria Symposium 2022: a vibrant discussion of progress made and challenges ahead from drug discovery to treatment. Trends Parasitol 2022; 38:711-718. [PMID: 35864072 PMCID: PMC9631389 DOI: 10.1016/j.pt.2022.06.005] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/22/2022] [Accepted: 06/22/2022] [Indexed: 10/17/2022]
Abstract
In recent years, the field of malaria research has made substantial progress in the areas of antimalarial drug resistance and discovery. These efforts are essential to combatting the devastating impact of malaria, which, in 2020, resulted in an estimated 241 million cases and 627 000 deaths. Recent advances in this area were presented at a Keystone Symposium entitled ‘Malaria: Confronting Challenges from Drug Discovery to Treatment’, held in person in Breckenridge, Colorado, in April 2022. Herein, we present a summary of the proceedings of this vibrant scientific exchange, which brought together a superb group of faculty, postdocs, and students from around the globe.
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Affiliation(s)
- Mariko Kanai
- Department of Microbiology and Immunology, Columbia University Irving Medical Center, New York, NY, USA.
| | - Laura M. Hagenah
- Department of Microbiology and Immunology, Columbia University Irving Medical Center, New York, NY, USA,Co-first authors
| | - Elizabeth A. Ashley
- Centre for Tropical Medicine and Global Health, Nuffield Department of Medicine, University of Oxford, Oxford, UK,Lao-Oxford-Mahosot Hospital-Wellcome Trust Research Unit, Mahosot Hospital, Vientiane, Laos
| | - Kelly Chibale
- Drug Discovery and Development (H3D) Centre, University of Cape Town, Rondebosch, South Africa; Institute of Infectious Disease and Molecular Medicine, University of Cape Town, Observatory, South Africa; South African Medical Research Council Drug Discovery and Development Research Unit, University of Cape Town, Rondebosch, South Africa; Department of Chemistry, University of Cape Town, Rondebosch, South Africa.
| | - David A. Fidock
- Department of Microbiology and Immunology, Columbia University Irving Medical Center, New York, NY, USA,Center for Malaria Therapeutics and Antimicrobial Resistance, Division of Infectious Diseases, Department of Medicine, Columbia University Irving Medical Center, New York, NY, USA,Correspondence: (D.A. Fidock)
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11
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Fontinha D, Arez F, Gal IR, Nogueira G, Moita D, Baeurle THH, Brito C, Spangenberg T, Alves PM, Prudêncio M. Pre-erythrocytic Activity of M5717 in Monotherapy and Combination in Preclinical Plasmodium Infection Models. ACS Infect Dis 2022; 8:721-727. [PMID: 35312290 PMCID: PMC9003234 DOI: 10.1021/acsinfecdis.1c00640] [Citation(s) in RCA: 4] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Abstract
![]()
Combination therapies
have emerged to mitigate Plasmodium drug resistance,
which has hampered the fight against malaria. M5717
is a potent multistage antiplasmodial drug under clinical development,
which inhibits parasite protein synthesis. The combination of M5717
with pyronaridine, an inhibitor of hemozoin formation, displays potent
activity against blood stage Plasmodium infection.
However, the impact of this therapy on liver infection by Plasmodium remains unknown. Here, we employed a recently
described 3D culture-based hepatic infection platform to evaluate
the activity of the M5717-pyronaridine combination against hepatic
infection by P. berghei. This effect was further
confirmed in vivo by employing the C57BL/6J rodent Plasmodium infection model. Collectively, our data demonstrate
that pyronaridine potentiates the activity of M5717 against P. berghei hepatic development. These preclinical results
contribute to the validation of pyronaridine as a suitable partner
drug for M5717, supporting the clinical evaluation of this novel antiplasmodial
combination therapy.
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Affiliation(s)
- Diana Fontinha
- Instituto de Medicina Molecular João Lobo Antunes, Faculdade de Medicina, Universidade de Lisboa, 1649-028 Lisboa, Portugal
| | - Francisca Arez
- iBET, Instituto de Biologia Experimental e Tecnológica, Apartado 12, 2780-901 Oeiras, Portugal
- Instituto de Tecnologia Química e Biológica António Xavier, Universidade Nova de Lisboa, Av. da República, 2780-157 Oeiras, Portugal
| | - Isabella Ramella Gal
- iBET, Instituto de Biologia Experimental e Tecnológica, Apartado 12, 2780-901 Oeiras, Portugal
- Instituto de Tecnologia Química e Biológica António Xavier, Universidade Nova de Lisboa, Av. da República, 2780-157 Oeiras, Portugal
| | - Gonçalo Nogueira
- Instituto de Medicina Molecular João Lobo Antunes, Faculdade de Medicina, Universidade de Lisboa, 1649-028 Lisboa, Portugal
| | - Diana Moita
- Instituto de Medicina Molecular João Lobo Antunes, Faculdade de Medicina, Universidade de Lisboa, 1649-028 Lisboa, Portugal
| | - Tobias Hyun Ho Baeurle
- Site Management − Analytics, the healthcare business of Merck KGaA, 64293 Darmstadt, Germany
| | - Catarina Brito
- iBET, Instituto de Biologia Experimental e Tecnológica, Apartado 12, 2780-901 Oeiras, Portugal
- Instituto de Tecnologia Química e Biológica António Xavier, Universidade Nova de Lisboa, Av. da República, 2780-157 Oeiras, Portugal
| | - Thomas Spangenberg
- Global Health Institute of Merck, Ares Trading S.A. (a subsidiary of Merck KGaA Darmstadt Germany), 1262 Eysins, Switzerland
| | - Paula M. Alves
- iBET, Instituto de Biologia Experimental e Tecnológica, Apartado 12, 2780-901 Oeiras, Portugal
- Instituto de Tecnologia Química e Biológica António Xavier, Universidade Nova de Lisboa, Av. da República, 2780-157 Oeiras, Portugal
| | - Miguel Prudêncio
- Instituto de Medicina Molecular João Lobo Antunes, Faculdade de Medicina, Universidade de Lisboa, 1649-028 Lisboa, Portugal
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12
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Synthesis and antiplasmodial activity of regioisomers and epimers of second-generation dual acting ivermectin hybrids. Sci Rep 2022; 12:564. [PMID: 35022455 PMCID: PMC8755717 DOI: 10.1038/s41598-021-04532-w] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/27/2021] [Accepted: 12/23/2021] [Indexed: 12/15/2022] Open
Abstract
With its strong effect on vector-borne diseases, and insecticidal effect on mosquito vectors of malaria, inhibition of sporogonic and blood-stage development of Plasmodium falciparum, as well as in vitro and in vivo impairment of the P. berghei development inside hepatocytes, ivermectin (IVM) continues to represent an antimalarial therapeutic worthy of investigation. The in vitro activity of the first-generation IVM hybrids synthesized by appending the IVM macrolide with heterocyclic and organometallic antimalarial pharmacophores, against the blood-stage and liver-stage infections by Plasmodium parasites prompted us to design second-generation molecular hybrids of IVM. Here, a structural modification of IVM to produce novel molecular hybrids by using sub-structures of 4- and 8-aminoquinolines, the time-tested antiplasmodial agents used for treating the blood and hepatic stage of Plasmodium infections, respectively, is presented. Successful isolation of regioisomers and epimers has been demonstrated, and the evaluation of their in vitro antiplasmodial activity against both the blood stages of P. falciparum and the hepatic stages of P. berghei have been undertaken. These compounds displayed structure-dependent antiplasmodial activity, in the nM range, which was more potent than that of IVM, its aglycon or primaquine, highlighting the superiority of this hybridization strategy in designing new antiplasmodial agents.
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13
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Vythilingam I, Chua TH, Liew JWK, Manin BO, Ferguson HM. The vectors of Plasmodium knowlesi and other simian malarias Southeast Asia: challenges in malaria elimination. ADVANCES IN PARASITOLOGY 2021; 113:131-189. [PMID: 34620382 DOI: 10.1016/bs.apar.2021.08.005] [Citation(s) in RCA: 15] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/20/2022]
Abstract
Plasmodium knowlesi, a simian malaria parasite of great public health concern has been reported from most countries in Southeast Asia and exported to various countries around the world. Currently P. knowlesi is the predominant species infecting humans in Malaysia. Besides this species, other simian malaria parasites such as P. cynomolgi and P. inui are also infecting humans in the region. The vectors of P. knowlesi and other Asian simian malarias belong to the Leucosphyrus Group of Anopheles mosquitoes which are generally forest dwelling species. Continual deforestation has resulted in these species moving into forest fringes, farms, plantations and human settlements along with their macaque hosts. Limited studies have shown that mosquito vectors are attracted to both humans and macaque hosts, preferring to bite outdoors and in the early part of the night. We here review the current status of simian malaria vectors and their parasites, knowledge of vector competence from experimental infections and discuss possible vector control measures. The challenges encountered in simian malaria elimination are also discussed. We highlight key knowledge gaps on vector distribution and ecology that may impede effective control strategies.
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Affiliation(s)
- Indra Vythilingam
- Department of Parasitology, University of Malaya, Kuala Lumpur, Malaysia.
| | - Tock Hing Chua
- Department of Pathobiology and Microbiology, Faculty of Medicine and Health Sciences, Universiti Sabah Malaysia, Kota Kinabalu, Sabah, Malaysia.
| | - Jonathan Wee Kent Liew
- Department of Parasitology, University of Malaya, Kuala Lumpur, Malaysia; Environmental Health Institute, National Environment Agency, Singapore, Singapore
| | - Benny O Manin
- Department of Pathobiology and Microbiology, Faculty of Medicine and Health Sciences, Universiti Sabah Malaysia, Kota Kinabalu, Sabah, Malaysia
| | - Heather M Ferguson
- Institute of Biodiversity, Animal Health and Comparative Medicine, University of Glasgow, Glasgow, Scotland, United Kingdom
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14
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Singh L, Singh K. Ivermectin: A Promising Therapeutic for Fighting Malaria. Current Status and Perspective. J Med Chem 2021; 64:9711-9731. [PMID: 34242031 DOI: 10.1021/acs.jmedchem.1c00498] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/22/2022]
Abstract
Finding new chemotherapeutic interventions to treat malaria through repurposing of time-tested drugs and rigorous design of new drugs using tools of rational drug design remains one of the most sought strategies at the disposal of medicinal chemists. Ivermectin, a semisynthetic derivative of avermectin B1, is among the efficacious drugs used in mass drug administration drives employed against onchocerciasis, lymphatic filariasis, and several other parasitic diseases in humans. In this review, we present the prowess of ivermectin, a potent endectocide, in the control of malaria through vector control to reduce parasite transmission combined with efficacious chemoprevention to reduce malaria-related fatalities.
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Affiliation(s)
- Lovepreet Singh
- Department of Chemistry, UGC Centre for Advanced Studies-II, Guru Nanak Dev University, Amritsar-143 005, India
| | - Kamaljit Singh
- Department of Chemistry, UGC Centre for Advanced Studies-II, Guru Nanak Dev University, Amritsar-143 005, India
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