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Ngum NH, Masakebenagha NE, Mahamat O. Antimalarial and Immunomodulatory Activities of Tithonia diversifolia (Asteraceae) Leave Flafonoids-Rich Extract Used in Cameroonian Traditional Medecine. SCIENTIFICA 2024; 2024:8645178. [PMID: 38962528 PMCID: PMC11221963 DOI: 10.1155/2024/8645178] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 01/22/2024] [Revised: 05/26/2024] [Accepted: 06/13/2024] [Indexed: 07/05/2024]
Abstract
Background Phytochemicals are considered the reliable source for the treatment of infection including malaria. Especially, phenols are known as potentially toxic to the growth and development of pathogens, among which flavonoids are the most extensively studied and play more intensive roles in ethnopharmacology. The immunological effect and role of T. diversifolia flavonoids-rich extract in treatment of malaria have therefore been examined in this study. Methods In vitro test against Plasmodium falciparum and 4-day suppressive and Rane's tests against Plasmodium berghei in mice were used to evaluate the antimalarial activities. TNF-α and INF-γ levels, phagocytic tests, and production of oxygen and nitrogen radical were assessed to appreciate the immunomodulatory activity. One-way analysis of variance followed by post hoc Student's t tests was used for data analysis. Results T. diversifolia flavonoids-rich extract at the concentrations ranging from 0.0004 mg/ml significantly (p < 0.05) inhibited in a concentration-dependent manner the growth of trophozoite up to 100% inhibition with 0.025 mg/ml at 24 and 48 hrs. Moreover, T. diversifolia flavonoids-rich extract reduced the level of parasitemia and improved in a dose-dependent manner the survival time of infected mice significantly (p < 0.05) compared to their control in 4-day suppressive test as well as in Rane's test. Additionally, T. diversifolia flavonoids-rich extract increased the TNF-α and INF-γ levels in rats infected by P. berghei. Furthermore, the flavonoid-rich extract enhanced weight of spleen in the rats, the metabolic and phagocytic activities of the peritoneal cells, and the concentration of nitric oxide and oxygen radicals in methylprednisolone-immunocompromised rats compared to the control (p < 0.05). Conclusion The study has revealed that T. diversifolia flavonoids-rich extract through its antiplasmodial and phagocytic activities is a promising treatment of malaria.
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Affiliation(s)
- Ntonifor Helen Ngum
- Department of ZoologyFaculty of SciencesUniversity of Bamenda, North West, Bamenda, Cameroon
| | - Ndoah Ellen Masakebenagha
- Department of Microbiology and ParasitologyFaculty of SciencesUniversity of Bamenda, North West, Bamenda, Cameroon
| | - Oumar Mahamat
- Department of ZoologyFaculty of SciencesUniversity of Bamenda, North West, Bamenda, Cameroon
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Simwela NV, Guiguemde WA, Straimer J, Regnault C, Stokes BH, Tavernelli LE, Yokokawa F, Taft B, Diagana TT, Barrett MP, Waters AP. A conserved metabolic signature associated with response to fast-acting anti-malarial agents. Microbiol Spectr 2023; 11:e0397622. [PMID: 37800971 PMCID: PMC10714989 DOI: 10.1128/spectrum.03976-22] [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: 10/02/2022] [Accepted: 01/27/2023] [Indexed: 10/07/2023] Open
Abstract
IMPORTANCE In malaria drug discovery, understanding the mode of action of lead compounds is important as it helps in predicting the potential emergence of drug resistance in the field when these drugs are eventually deployed. In this study, we have employed metabolomics technologies to characterize the potential targets of anti-malarial drug candidates in the developmental pipeline at NITD. We show that NITD fast-acting leads belonging to spiroindolone and imidazothiadiazole class induce a common biochemical theme in drug-exposed malaria parasites which is similar to another fast-acting, clinically available drug, DHA. These biochemical features which are absent in a slower acting NITD lead (GNF17) point to hemoglobin digestion and inhibition of the pyrimidine pathway as potential action points for these drugs. These biochemical themes can be used to identify and inform on the mode of action of fast drug candidates of similar profiles in future drug discovery programs.
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Affiliation(s)
- Nelson V. Simwela
- Institute of Infection, Immunity and Inflammation, Wellcome Centre for Integrative Parasitology, University of Glasgow, Glasgow, United Kingdom
| | | | - Judith Straimer
- Novartis Institute for Tropical Diseases, Emeryville, California, USA
| | - Clement Regnault
- Institute of Infection, Immunity and Inflammation, Wellcome Centre for Integrative Parasitology, University of Glasgow, Glasgow, United Kingdom
| | - Barbara H. Stokes
- Institute of Infection, Immunity and Inflammation, Wellcome Centre for Integrative Parasitology, University of Glasgow, Glasgow, United Kingdom
| | - Luis E. Tavernelli
- Institute of Infection, Immunity and Inflammation, Wellcome Centre for Integrative Parasitology, University of Glasgow, Glasgow, United Kingdom
| | - Fumiaki Yokokawa
- Novartis Institute for Tropical Diseases, Emeryville, California, USA
| | - Benjamin Taft
- Novartis Institute for Tropical Diseases, Emeryville, California, USA
| | | | - Michael P. Barrett
- Institute of Infection, Immunity and Inflammation, Wellcome Centre for Integrative Parasitology, University of Glasgow, Glasgow, United Kingdom
| | - Andrew P. Waters
- Institute of Infection, Immunity and Inflammation, Wellcome Centre for Integrative Parasitology, University of Glasgow, Glasgow, United Kingdom
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3
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The enemy within: lipid asymmetry in intracellular parasite-host interactions. Emerg Top Life Sci 2023; 7:67-79. [PMID: 36820809 DOI: 10.1042/etls20220089] [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: 10/26/2022] [Revised: 01/26/2023] [Accepted: 02/07/2023] [Indexed: 02/24/2023]
Abstract
Eukaryotic pathogens with an intracellular parasitic lifestyle are shielded from extracellular threats during replication and growth. In addition to many nutrients, parasites scavenge host cell lipids to establish complex membrane structures inside their host cells. To counteract the disturbance of the host cell plasma membrane they have evolved strategies to regulate phospholipid asymmetry. In this review, the function and importance of lipid asymmetry in the interactions of intracellular protozoan parasites with the target and immune cells of the host are highlighted. The malaria parasite Plasmodium infects red blood cells and extensively refurbishes these terminally differentiated cells. Cholesterol depletion and an altered intracellular calcium ion homeostasis can lead to disruption in erythrocyte membrane asymmetry and increased exposure of phosphatidylserine (PS). Binding to the PS receptor on monocytes and macrophages results in phagocytosis and destruction of infected erythrocytes. Leishmania parasites display apoptotic mimicry by actively enhancing PS exposure on their surface to trigger increased infection of macrophages. In extracellular Toxoplasma gondii a P4-type ATPase/CDC50 co-chaperone pair functions as a flippase important for exocytosis of specialised secretory organelles. Identification and functional analysis of parasite lipid-translocating proteins, i.e. flippases, floppases, and scramblases, will be central for the recognition of the molecular mechanisms of parasite/host interactions. Ultimately, a better understanding of parasitic diseases, host immunity, and immune escape by parasites require more research on the dynamics of phospholipid bilayers of parasites and the infected host cell.
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Barnes CBG, Dans MG, Jonsdottir TK, Crabb BS, Gilson PR. PfATP4 inhibitors in the Medicines for Malaria Venture Malaria Box and Pathogen Box block the schizont-to-ring transition by inhibiting egress rather than invasion. Front Cell Infect Microbiol 2022; 12:1060202. [PMID: 36530423 PMCID: PMC9747762 DOI: 10.3389/fcimb.2022.1060202] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/03/2022] [Accepted: 11/15/2022] [Indexed: 12/05/2022] Open
Abstract
The cation efflux pump Plasmodium falciparum ATPase 4 (PfATP4) maintains Na+ homeostasis in malaria parasites and has been implicated in the mechanism of action of many structurally diverse antimalarial agents, including >7% of the antimalarial compounds in the Medicines for Malaria Venture's 'Malaria Box' and 'Pathogen Box'. Recent screens of the 'Malaria Box' and 'Pathogen Box' revealed that many PfATP4 inhibitors prevent parasites from exiting their host red blood cell (egress) or entering new host cells (invasion), suggesting that these compounds may have additional molecular targets involved in egress or invasion. Here, we demonstrate that five PfATP4 inhibitors reduce egress but not invasion. These compounds appear to inhibit egress by blocking the activation of protein kinase G, an enzyme that, once stimulated, rapidly activates parasite egress. We establish a direct link between egress and PfATP4 function by showing that the inhibition of egress is attenuated in a Na+-depleted environment and in parasites with a mutation in pfatp4. Finally, we show that PfATP4 inhibitors induce host cell lysis when administered prior to the completion of parasite replication. Since host cell lysis mimics egress but is not followed by invasion, this phenomenon likely explains why several PfATP4 inhibitors were previously classified as invasion inhibitors. Collectively, our results confirm that PfATP4-mediated Na+ efflux is critical to the regulation of parasite egress.
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Affiliation(s)
- Claudia B. G. Barnes
- Life Sciences, Burnet Institute, Melbourne, VIC, Australia,Department of Medicine, The University of Melbourne, Melbourne, VIC, Australia
| | - Madeline G. Dans
- Life Sciences, Burnet Institute, Melbourne, VIC, Australia,School of Medicine, Deakin University, Geelong, VIC, Australia
| | - Thorey K. Jonsdottir
- Life Sciences, Burnet Institute, Melbourne, VIC, Australia,Department of Immunology and Pathology, Monash University, Melbourne, VIC, Australia
| | - Brendan S. Crabb
- Life Sciences, Burnet Institute, Melbourne, VIC, Australia,Department of Microbiology and Immunology, The University of Melbourne, Parkville, VIC, Australia,Department of Immunology and Pathology, Monash University, Melbourne, VIC, Australia
| | - Paul R. Gilson
- Life Sciences, Burnet Institute, Melbourne, VIC, Australia,Department of Microbiology and Immunology, The University of Melbourne, Parkville, VIC, Australia,*Correspondence: Paul R. Gilson,
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5
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Qiu D, Pei JV, Rosling JEO, Thathy V, Li D, Xue Y, Tanner JD, Penington JS, Aw YTV, Aw JYH, Xu G, Tripathi AK, Gnadig NF, Yeo T, Fairhurst KJ, Stokes BH, Murithi JM, Kümpornsin K, Hasemer H, Dennis ASM, Ridgway MC, Schmitt EK, Straimer J, Papenfuss AT, Lee MCS, Corry B, Sinnis P, Fidock DA, van Dooren GG, Kirk K, Lehane AM. A G358S mutation in the Plasmodium falciparum Na + pump PfATP4 confers clinically-relevant resistance to cipargamin. Nat Commun 2022; 13:5746. [PMID: 36180431 PMCID: PMC9525273 DOI: 10.1038/s41467-022-33403-9] [Citation(s) in RCA: 11] [Impact Index Per Article: 5.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/26/2022] [Accepted: 09/16/2022] [Indexed: 11/30/2022] Open
Abstract
Diverse compounds target the Plasmodium falciparum Na+ pump PfATP4, with cipargamin and (+)-SJ733 the most clinically-advanced. In a recent clinical trial for cipargamin, recrudescent parasites emerged, with most having a G358S mutation in PfATP4. Here, we show that PfATP4G358S parasites can withstand micromolar concentrations of cipargamin and (+)-SJ733, while remaining susceptible to antimalarials that do not target PfATP4. The G358S mutation in PfATP4, and the equivalent mutation in Toxoplasma gondii ATP4, decrease the sensitivity of ATP4 to inhibition by cipargamin and (+)-SJ733, thereby protecting parasites from disruption of Na+ regulation. The G358S mutation reduces the affinity of PfATP4 for Na+ and is associated with an increase in the parasite's resting cytosolic [Na+]. However, no defect in parasite growth or transmissibility is observed. Our findings suggest that PfATP4 inhibitors in clinical development should be tested against PfATP4G358S parasites, and that their combination with unrelated antimalarials may mitigate against resistance development.
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Affiliation(s)
- Deyun Qiu
- Research School of Biology, Australian National University, Canberra, ACT, 2600, Australia
| | - Jinxin V Pei
- Research School of Biology, Australian National University, Canberra, ACT, 2600, Australia
| | - James E O Rosling
- Research School of Biology, Australian National University, Canberra, ACT, 2600, Australia
| | - Vandana Thathy
- Department of Microbiology & Immunology, Columbia University Irving Medical Center, New York, NY, 10032, USA
| | - Dongdi Li
- Research School of Biology, Australian National University, Canberra, ACT, 2600, Australia
| | - Yi Xue
- Research School of Biology, Australian National University, Canberra, ACT, 2600, Australia
| | - John D Tanner
- Research School of Biology, Australian National University, Canberra, ACT, 2600, Australia
| | - Jocelyn Sietsma Penington
- Bioinformatic Division, The Walter & Eliza Hall Institute of Medical Research, Parkville, VIC, 3052, Australia
| | - Yi Tong Vincent Aw
- Research School of Biology, Australian National University, Canberra, ACT, 2600, Australia
| | - Jessica Yi Han Aw
- Research School of Biology, Australian National University, Canberra, ACT, 2600, Australia
| | - Guoyue Xu
- Department of Molecular Microbiology & Immunology and Johns Hopkins Malaria Institute, Johns Hopkins School of Public Health, Baltimore, MD, 21205, USA
| | - Abhai K Tripathi
- Department of Molecular Microbiology & Immunology and Johns Hopkins Malaria Institute, Johns Hopkins School of Public Health, Baltimore, MD, 21205, USA
| | - Nina F Gnadig
- Department of Microbiology & Immunology, Columbia University Irving Medical Center, New York, NY, 10032, USA
| | - Tomas Yeo
- Department of Microbiology & Immunology, Columbia University Irving Medical Center, New York, NY, 10032, USA
| | - Kate J Fairhurst
- Department of Microbiology & Immunology, Columbia University Irving Medical Center, New York, NY, 10032, USA
| | - Barbara H Stokes
- Department of Microbiology & Immunology, Columbia University Irving Medical Center, New York, NY, 10032, USA
| | - James M Murithi
- Department of Microbiology & Immunology, Columbia University Irving Medical Center, New York, NY, 10032, USA
| | | | - Heath Hasemer
- Research School of Biology, Australian National University, Canberra, ACT, 2600, Australia
| | - Adelaide S M Dennis
- Research School of Biology, Australian National University, Canberra, ACT, 2600, Australia
| | - Melanie C Ridgway
- Research School of Biology, Australian National University, Canberra, ACT, 2600, Australia
| | | | - Judith Straimer
- Novartis Institute for Tropical Diseases, Emeryville, CA, 94608, USA
| | - Anthony T Papenfuss
- Bioinformatic Division, The Walter & Eliza Hall Institute of Medical Research, Parkville, VIC, 3052, Australia
- Department of Medical Biology, The University of Melbourne, Parkville, VIC, 3052, Australia
| | - Marcus C S Lee
- Wellcome Sanger Institute, Wellcome Genome Campus, Hinxton, CB10 1SA, UK
| | - Ben Corry
- Research School of Biology, Australian National University, Canberra, ACT, 2600, Australia
| | - Photini Sinnis
- Department of Molecular Microbiology & Immunology and Johns Hopkins Malaria Institute, Johns Hopkins School of Public Health, Baltimore, MD, 21205, USA
| | - David A Fidock
- Department of Microbiology & Immunology, Columbia University Irving Medical Center, New York, NY, 10032, USA
- Center for Malaria Therapeutics and Antimicrobial Resistance, Division of Infectious Diseases, Department of Medicine, Columbia University Irving Medical Center, New York, NY, 10032, USA
| | - Giel G van Dooren
- Research School of Biology, Australian National University, Canberra, ACT, 2600, Australia
| | - Kiaran Kirk
- Research School of Biology, Australian National University, Canberra, ACT, 2600, Australia
| | - Adele M Lehane
- Research School of Biology, Australian National University, Canberra, ACT, 2600, Australia.
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6
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Maier AG, van Ooij C. The role of cholesterol in invasion and growth of malaria parasites. Front Cell Infect Microbiol 2022; 12:984049. [PMID: 36189362 PMCID: PMC9522969 DOI: 10.3389/fcimb.2022.984049] [Citation(s) in RCA: 5] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/01/2022] [Accepted: 08/15/2022] [Indexed: 11/24/2022] Open
Abstract
Malaria parasites are unicellular eukaryotic pathogens that develop through a complex lifecycle involving two hosts, an anopheline mosquito and a vertebrate host. Throughout this lifecycle, the parasite encounters widely differing conditions and survives in distinct ways, from an intracellular lifestyle in the vertebrate host to exclusively extracellular stages in the mosquito. Although the parasite relies on cholesterol for its growth, the parasite has an ambiguous relationship with cholesterol: cholesterol is required for invasion of host cells by the parasite, including hepatocytes and erythrocytes, and for the development of the parasites in those cells. However, the parasite is unable to produce cholesterol itself and appears to remove cholesterol actively from its own plasma membrane, thereby setting up a cholesterol gradient inside the infected host erythrocyte. Overall a picture emerges in which the parasite relies on host cholesterol and carefully controls its transport. Here, we describe the role of cholesterol at the different lifecycle stages of the parasites.
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Affiliation(s)
- Alexander G. Maier
- Research School of Biology, The Australian National University, Canberra ACT, Australia
- *Correspondence: Alexander G. Maier, ; Christiaan van Ooij,
| | - Christiaan van Ooij
- Department of Infection Biology, London School of Hygiene & Tropical Medicine, London, United Kingdom
- *Correspondence: Alexander G. Maier, ; Christiaan van Ooij,
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7
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Bernard MM, Mohanty A, Rajendran V. Title: A Comprehensive Review on Classifying Fast-acting and Slow-acting Antimalarial Agents Based on Time of Action and Target Organelle of Plasmodium sp. Pathog Dis 2022; 80:6589403. [PMID: 35588061 DOI: 10.1093/femspd/ftac015] [Citation(s) in RCA: 2] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/18/2021] [Revised: 03/20/2022] [Accepted: 05/17/2022] [Indexed: 11/13/2022] Open
Abstract
The clinical resistance towards malarial parasites has rendered many antimalarials ineffective, likely due to a lack of understanding of time of action and stage specificity of all life stages. Therefore, to tackle this problem a more incisive comprehensive analysis of the fast and slow-acting profile of antimalarial agents relating to parasite time-kill kinetics and the target organelle on the progression of blood-stage parasites was carried out. It is evident from numerous findings that drugs targeting food vacuole, nuclear components, and endoplasmic reticulum mainly exhibit a fast-killing phenotype within 24h affecting first-cycle activity. Whereas drugs targeting mitochondria, apicoplast, microtubules, parasite invasion and egress exhibit a largely slow-killing phenotype within 96-120h, affecting second-cycle activity with few exemptions as moderately fast-killing. It is essential to understand the susceptibility of drugs on rings, trophozoites, schizonts, merozoites, and the appearance of organelle at each stage of 48h intraerythrocytic parasite cycle. Therefore, these parameters may facilitate the paradigm for understanding the timing of antimalarials action in deciphering its precise mechanism linked with time. Thus, classifying drugs based on the time of killing may promote designing new combination regimens against varied strains of P. falciparum and evaluating potential clinical resistance.
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Affiliation(s)
- Monika Marie Bernard
- Department of Microbiology, School of Life Sciences, Pondicherry University, Puducherry 605014, India
| | - Abhinab Mohanty
- Department of Microbiology, School of Life Sciences, Pondicherry University, Puducherry 605014, India
| | - Vinoth Rajendran
- Department of Microbiology, School of Life Sciences, Pondicherry University, Puducherry 605014, India
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8
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Selective Inhibition of Plasmodium falciparum ATPase 6 by Artemisinins and Identification of New Classes of Inhibitors after Expression in Yeast. Antimicrob Agents Chemother 2022; 66:e0207921. [PMID: 35465707 PMCID: PMC9112895 DOI: 10.1128/aac.02079-21] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/24/2023] Open
Abstract
Treatment failures with artemisinin combination therapies (ACTs) threaten global efforts to eradicate malaria. They highlight the importance of identifying drug targets and new inhibitors and of studying how existing antimalarial classes work. Here, we report the successful development of a heterologous expression-based compound-screening tool. The validated drug target Plasmodium falciparum ATPase 6 (PfATP6) and a mammalian orthologue (sarco/endoplasmic reticulum calcium ATPase 1a [SERCA1a]) were functionally expressed in Saccharomyces cerevisiae, providing a robust, sensitive, and specific screening tool. Whole-cell and in vitro assays consistently demonstrated inhibition and labeling of PfATP6 by artemisinins. Mutations in PfATP6 resulted in fitness costs that were ameliorated in the presence of artemisinin derivatives when studied in the yeast model. As previously hypothesized, PfATP6 is a target of artemisinins. Mammalian SERCA1a can be mutated to become more susceptible to artemisinins. The inexpensive, low-technology yeast screening platform has identified unrelated classes of druggable PfATP6 inhibitors. Resistance to artemisinins may depend on mechanisms that can concomitantly address multitargeting by artemisinins and fitness costs of mutations that reduce artemisinin susceptibility.
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9
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Abstract
Cholesterol is the most abundant lipid in the erythrocyte. During its blood-stage development, the malaria parasite establishes an active cholesterol gradient across the various membrane systems within the infected erythrocyte. Interestingly, some antimalarial compounds have recently been shown to disrupt cholesterol homeostasis in the intraerythrocytic stages of Plasmodium falciparum. These studies point to the importance of cholesterol for parasite growth. Previously, reduction of cholesterol from the erythrocyte membrane by treatment with methyl-β-cyclodextrin (MβCD) was shown to inhibit parasite invasion and growth. In addition, MβCD treatment of trophozoite-stage P. falciparum was shown to result in parasite expulsion from the host cell. We have revisited these phenomena by using live video microscopy, ultrastructural analysis, and response to antimalarial compounds. By using time-lapse video microscopy of fluorescently tagged parasites, we show that MβCD treatment for just 30 min causes dramatic expulsion of the trophozoite-stage parasites. This forceful expulsion occurs within 10 s. Remarkably, the plasma membrane of the host cell from which the parasite has been expelled does not appear to be compromised. The parasitophorous vacuolar membrane (PVM) continued to surround the extruded parasite, but the PVM appeared damaged. Treatment with antimalarial compounds targeting PfATP4 or PfNCR1 prevented MβCD-mediated extrusion of the parasites, pointing to a potential role of cholesterol dynamics underlying the expulsion phenomena. We also confirmed the essential role of erythrocyte plasma membrane cholesterol for invasion and growth of P. falciparum. This defect can be partially complemented by cholesterol and desmosterol but not with epicholesterol, revealing stereospecificity underlying cholesterol function. Overall, our studies advance previous observations and reveal unusual cell biological features underlying cholesterol depletion of the infected erythrocyte plasma membrane. IMPORTANCE Malaria remains a major challenge in much of the world. Symptoms of malaria are caused by the growth of parasites belonging to Plasmodium spp. inside the red blood cells (RBCs), leading to their destruction. The parasite depends upon its host for much of its nutritional needs. Cholesterol is a major lipid in the RBC plasma membrane, which is the only source of this lipid for malaria parasites. We have previously shown that certain new antimalarial compounds disrupt cholesterol homeostasis in P. falciparum. Here, we use live time-lapse video microscopy to show dramatic expulsion of the parasite from the host RBC when the cholesterol content of the RBC is reduced. Remarkably, this expulsion is inhibited by the antimalarials that disrupt lipid homeostasis. We also show stereospecificity of cholesterol in supporting parasite growth inside RBC. Overall, these results point to a critical role of cholesterol in the physiology of malaria parasites.
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10
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Frasse PM, Miller JJ, Polino AJ, Soleimani E, Zhu JS, Jakeman DL, Jez JM, Goldberg DE, Odom John AR. Enzymatic and structural characterization of HAD5, an essential phosphomannomutase of malaria-causing parasites. J Biol Chem 2022; 298:101550. [PMID: 34973333 PMCID: PMC8808168 DOI: 10.1016/j.jbc.2021.101550] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/21/2021] [Revised: 12/22/2021] [Accepted: 12/23/2021] [Indexed: 11/05/2022] Open
Abstract
The malaria-causing parasite Plasmodium falciparum is responsible for over 200 million infections and 400,000 deaths per year. At multiple stages during its complex life cycle, P. falciparum expresses several essential proteins tethered to its surface by glycosylphosphatidylinositol (GPI) anchors, which are critical for biological processes such as parasite egress and reinvasion of host red blood cells. Targeting this pathway therapeutically has the potential to broadly impact parasite development across several life stages. Here, we characterize an upstream component of parasite GPI anchor biosynthesis, the putative phosphomannomutase (PMM) (EC 5.4.2.8), HAD5 (PF3D7_1017400). We confirmed the PMM and phosphoglucomutase activities of purified recombinant HAD5 by developing novel linked enzyme biochemical assays. By regulating the expression of HAD5 in transgenic parasites with a TetR-DOZI-inducible knockdown system, we demonstrated that HAD5 is required for malaria parasite egress and erythrocyte reinvasion, and we assessed the role of HAD5 in GPI anchor synthesis by autoradiography of radiolabeled glucosamine and thin layer chromatography. Finally, we determined the three-dimensional X-ray crystal structure of HAD5 and identified a substrate analog that specifically inhibits HAD5 compared to orthologous human PMMs in a time-dependent manner. These findings demonstrate that the GPI anchor biosynthesis pathway is exceptionally sensitive to inhibition in parasites and that HAD5 has potential as a specific, multistage antimalarial target.
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Affiliation(s)
- Philip M Frasse
- Division of Infectious Diseases, Departments of Medicine and Molecular Microbiology, Washington University School of Medicine, St. Louis, Missouri, USA
| | - Justin J Miller
- Department of Biology, Washington University in St. Louis, St. Louis, Missouri, USA
| | - Alexander J Polino
- Division of Infectious Diseases, Departments of Medicine and Molecular Microbiology, Washington University School of Medicine, St. Louis, Missouri, USA
| | - Ebrahim Soleimani
- College of Pharmacy, Dalhousie University, Halifax, Nova Scotia, Canada; Department of Chemistry, Razi University, Kermanshah, Iran
| | - Jian-She Zhu
- College of Pharmacy, Dalhousie University, Halifax, Nova Scotia, Canada
| | - David L Jakeman
- College of Pharmacy, Dalhousie University, Halifax, Nova Scotia, Canada; Department of Chemistry, Dalhousie University, Halifax, Nova Scotia, Canada
| | - Joseph M Jez
- Department of Biology, Washington University in St. Louis, St. Louis, Missouri, USA
| | - Daniel E Goldberg
- Division of Infectious Diseases, Departments of Medicine and Molecular Microbiology, Washington University School of Medicine, St. Louis, Missouri, USA
| | - Audrey R Odom John
- Division of Infectious Diseases, Department of Pediatrics, Children's Hospital of Philadelphia, University of Pennsylvania, Philadelphia, Pennsylvania, USA.
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11
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Tewari SG, Kwan B, Elahi R, Rajaram K, Reifman J, Prigge ST, Vaidya AB, Wallqvist A. Metabolic adjustments of blood-stage Plasmodium falciparum in response to sublethal pyrazoleamide exposure. Sci Rep 2022; 12:1167. [PMID: 35064153 PMCID: PMC8782945 DOI: 10.1038/s41598-022-04985-7] [Citation(s) in RCA: 4] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/23/2021] [Accepted: 01/04/2022] [Indexed: 11/08/2022] Open
Abstract
Due to the recurring loss of antimalarial drugs to resistance, there is a need for novel targets, drugs, and combination therapies to ensure the availability of current and future countermeasures. Pyrazoleamides belong to a novel class of antimalarial drugs that disrupt sodium ion homeostasis, although the exact consequences of this disruption in Plasmodium falciparum remain under investigation. In vitro experiments demonstrated that parasites carrying mutations in the metabolic enzyme PfATP4 develop resistance to pyrazoleamide compounds. However, the underlying mechanisms that allow mutant parasites to evade pyrazoleamide treatment are unclear. Here, we first performed experiments to identify the sublethal dose of a pyrazoleamide compound (PA21A092) that caused a significant reduction in growth over one intraerythrocytic developmental cycle (IDC). At this drug concentration, we collected transcriptomic and metabolomic data at multiple time points during the IDC to quantify gene- and metabolite-level alterations in the treated parasites. To probe the effects of pyrazoleamide treatment on parasite metabolism, we coupled the time-resolved omics data with a metabolic network model of P. falciparum. We found that the drug-treated parasites adjusted carbohydrate metabolism to enhance synthesis of myoinositol-a precursor for phosphatidylinositol biosynthesis. This metabolic adaptation caused a decrease in metabolite flux through the pentose phosphate pathway, causing a decreased rate of RNA synthesis and an increase in oxidative stress. Our model analyses suggest that downstream consequences of enhanced myoinositol synthesis may underlie adjustments that could lead to resistance emergence in P. falciparum exposed to a sublethal dose of a pyrazoleamide drug.
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Affiliation(s)
- Shivendra G Tewari
- Department of Defense Biotechnology High Performance Computing Software Applications Institute, Telemedicine and Advanced Technology Research Center, U.S. Army Medical Research and Development Command, Fort Detrick, MD, USA.
- The Henry M. Jackson Foundation for the Advancement of Military Medicine, Inc., Bethesda, MD, USA.
| | - Bobby Kwan
- Department of Molecular Microbiology and Immunology, Johns Hopkins University, Baltimore, MD, USA
| | - Rubayet Elahi
- Department of Molecular Microbiology and Immunology, Johns Hopkins University, Baltimore, MD, USA
| | - Krithika Rajaram
- Department of Molecular Microbiology and Immunology, Johns Hopkins University, Baltimore, MD, USA
| | - Jaques Reifman
- Department of Defense Biotechnology High Performance Computing Software Applications Institute, Telemedicine and Advanced Technology Research Center, U.S. Army Medical Research and Development Command, Fort Detrick, MD, USA
| | - Sean T Prigge
- Department of Molecular Microbiology and Immunology, Johns Hopkins University, Baltimore, MD, USA
| | - Akhil B Vaidya
- Department of Microbiology and Immunology, Center for Molecular Parasitology, Drexel University College of Medicine, Philadelphia, PA, USA
| | - Anders Wallqvist
- Department of Defense Biotechnology High Performance Computing Software Applications Institute, Telemedicine and Advanced Technology Research Center, U.S. Army Medical Research and Development Command, Fort Detrick, MD, USA.
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12
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Kumar V, Rumaisha, Behl A, Munjal A, Abid M, Singh S. Prefoldin subunit 6 of Plasmodium falciparum binds merozoite surface protein-1 (MSP-1). FEBS Open Bio 2020; 12:1050-1060. [PMID: 33145997 PMCID: PMC9063436 DOI: 10.1002/2211-5463.13022] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/16/2020] [Revised: 10/21/2020] [Accepted: 11/02/2020] [Indexed: 11/23/2022] Open
Abstract
Malaria is a human disease caused by eukaryotic protozoan parasites of the Plasmodium genus. Plasmodium falciparum (Pf) causes the most lethal form of human malaria and is responsible for widespread mortality worldwide. Prefoldin is a heterohexameric molecular complex that binds and delivers unfolded proteins to chaperonin for correct folding. The prefoldin PFD6 is predicted to interact with merozoite surface protein‐1 (MSP‐1), a protein well known to play a pivotal role in erythrocyte binding and invasion by Plasmodium merozoites. We previously found that the P. falciparum (Pf) genome contains six prefoldin genes and a prefoldin‐like gene whose molecular functions are unidentified. Here, we analyzed the expression of PfPFD‐6 during the asexual blood stages of the parasite and investigated its interacting partners. PfPFD‐6 was found to be significantly expressed at the trophozoite and schizont stages. Pull‐down assays suggest PfPFD‐6 interacts with MSP‐1. In silico analysis suggested critical residues involved in the PfPFD‐6‐MSP‐1 interaction. Our data suggest PfPFD‐6 may play a role in stabilizing or trafficking MSP‐1.
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Affiliation(s)
- Vikash Kumar
- Special Centre for Molecular Medicine, Jawaharlal Nehru University, New Delhi, India
| | - Rumaisha
- Medicinal Chemistry laboratory, Department of Biosciences, Faculty of Natural Sciences, Jamia Millia Islamia, New Delhi, India
| | - Ankita Behl
- Special Centre for Molecular Medicine, Jawaharlal Nehru University, New Delhi, India
| | - Akshay Munjal
- Special Centre for Molecular Medicine, Jawaharlal Nehru University, New Delhi, India
| | - Mohammad Abid
- Medicinal Chemistry laboratory, Department of Biosciences, Faculty of Natural Sciences, Jamia Millia Islamia, New Delhi, India
| | - Shailja Singh
- Special Centre for Molecular Medicine, Jawaharlal Nehru University, New Delhi, India
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13
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Madhav H, Hoda N. An insight into the recent development of the clinical candidates for the treatment of malaria and their target proteins. Eur J Med Chem 2020; 210:112955. [PMID: 33131885 DOI: 10.1016/j.ejmech.2020.112955] [Citation(s) in RCA: 12] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/03/2020] [Revised: 10/08/2020] [Accepted: 10/19/2020] [Indexed: 01/18/2023]
Abstract
Malaria is an endemic disease, prevalent in tropical and subtropical regions which cost half of million deaths annually. The eradication of malaria is one of the global health priority nevertheless, current therapeutic efforts seem to be insufficient due to the emergence of drug resistance towards most of the available drugs, even first-line treatment ACT, unavailability of the vaccine, and lack of drugs with a new mechanism of action. Intensification of antimalarial research in recent years has resulted into the development of single dose multistage therapeutic agents which has advantage of overcoming the antimalarial drug resistance. The present review explored the current progress in the development of new promising antimalarials against prominent target proteins that have the potential to be a clinical candidate. Here, we also reviewed different aspects of drug resistance and highlighted new drug candidates that are currently in a clinical trial or clinical development, along with a few other molecules with excellent antimalarial activity overs ACTs. The summarized scientific value of previous approaches and structural features of antimalarials related to the activity are highlighted that will be helpful for the development of next-generation antimalarials.
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Affiliation(s)
- Hari Madhav
- Drug Design and Synthesis Laboratory, Department of Chemistry, Jamia Millia Islamia (A Central University), New Delhi, 110025, India.
| | - Nasimul Hoda
- Drug Design and Synthesis Laboratory, Department of Chemistry, Jamia Millia Islamia (A Central University), New Delhi, 110025, India.
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14
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Tripathi G, Singh AK, Kumar A. Arylpyrazoles: Heterocyclic Scaffold of Immense Therapeutic Application. CURR ORG CHEM 2020. [DOI: 10.2174/1570179417999200628035645] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/08/2023]
Abstract
Among the major class of heterocycles, the N-heterocycles, such as pyrazoles,
are scaffolds of vast medicinal values. Various drugs and other biologically active molecules
are known to contain these N-heterocycles as core motifs. Specifically, arylpyrazoles
have exhibited a diverse range of biological activities, including anti-inflammatory, anticancerous,
antimicrobial and various others. For instance, arylpyrazoles are present as
core moieties in various insecticides, fungicides and drugs such as Celebrex and Trocoxil.
The present review will be highlighting the significant therapeutic importance of pyrazole
derivatives developed in the last few years.
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Affiliation(s)
- Garima Tripathi
- Department of Chemistry, T. N. B. College, Tilka Manjhi Bhagalpur University, Bhagalpur, Bihar, India
| | - Anil Kumar Singh
- Department of Chemistry, School of Physical Sciences, Mahatma Gandhi Central University, Bihar, India
| | - Abhijeet Kumar
- Department of Chemistry, School of Physical Sciences, Mahatma Gandhi Central University, Bihar, India
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15
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The Functioning of Na +-ATPases from Protozoan Parasites: Are These Pumps Targets for Antiparasitic Drugs? Cells 2020; 9:cells9102225. [PMID: 33023071 PMCID: PMC7600311 DOI: 10.3390/cells9102225] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/04/2020] [Revised: 09/16/2020] [Accepted: 09/17/2020] [Indexed: 12/17/2022] Open
Abstract
The ENA ATPases (from exitus natru: the exit of sodium) belonging to the P-type ATPases are structurally very similar to the sarco/endoplasmic reticulum Ca2+-ATPase (SERCA); they exchange Na+ for H+ and, therefore, are also known as Na+-ATPases. ENA ATPases are required in alkaline milieu, as in the case for Aspergillus, where other transporters cannot mediate an uphill Na+ efflux. They are also important for salt tolerance, as described for Arabidopsis. During their life cycles, protozoan parasites might encounter a high pH environment, thus allowing consideration of ENA ATPases as possible targets for controlling certain severe parasitic diseases, such as Chagas' Disease. Phylogenetic analysis has now shown that, besides the types IIA, IIB, IIC, and IID P-type ATPases, there exists a 5th subgroup of ATPases classified as ATP4-type ATPases, found in Plasmodium falciparum and Toxoplasma gondii. In malaria, for example, some drugs targeting PfATP4 destroy Na+ homeostasis; these drugs, which include spiroindolones, are now in clinical trials. The ENA P-type (IID P-type ATPase) and ATP4-type ATPases have no structural homologue in mammalian cells, appearing only in fungi, plants, and protozoan parasites, e.g., Trypanosoma cruzi, Leishmania sp., Toxoplasma gondii, and Plasmodium falciparum. This exclusivity makes Na+-ATPase a potential candidate for the biologically-based design of new therapeutic interventions; for this reason, Na+-ATPases deserves more attention.
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16
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Wellems TE, Sá JM, Su XZ, Connelly SV, Ellis AC. 'Artemisinin Resistance': Something New or Old? Something of a Misnomer? Trends Parasitol 2020; 36:735-744. [PMID: 32586776 DOI: 10.1016/j.pt.2020.05.013] [Citation(s) in RCA: 14] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/03/2020] [Revised: 05/22/2020] [Accepted: 05/25/2020] [Indexed: 01/02/2023]
Abstract
Artemisinin and its derivatives (ART) are crucial first-line antimalarial drugs that rapidly clear parasitemia, but recrudescences of the infection frequently follow ART monotherapy. For this reason, ART must be used in combination with one or more partner drugs that ensure complete cure. The ability of malaria parasites to survive ART monotherapy may relate to an innate growth bistability phenomenon whereby a fraction of the drug-exposed population enters into metabolic quiescence (dormancy) as persister forms. Characterization of the events that underlie entry and waking from persistence may lead to lasting breakthroughs in malaria chemotherapy that can prevent recrudescences and protect the future of ART-based combination therapies.
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Affiliation(s)
- Thomas E Wellems
- Laboratory of Malaria and Vector Research, National Institute of Allergy and Infectious Diseases, National Institutes of Health, Bethesda, MD 20892, USA.
| | - Juliana M Sá
- Laboratory of Malaria and Vector Research, National Institute of Allergy and Infectious Diseases, National Institutes of Health, Bethesda, MD 20892, USA
| | - Xin-Zhuan Su
- Laboratory of Malaria and Vector Research, National Institute of Allergy and Infectious Diseases, National Institutes of Health, Bethesda, MD 20892, USA
| | - Sean V Connelly
- Laboratory of Malaria and Vector Research, National Institute of Allergy and Infectious Diseases, National Institutes of Health, Bethesda, MD 20892, USA
| | - Angela C Ellis
- Laboratory of Malaria and Vector Research, National Institute of Allergy and Infectious Diseases, National Institutes of Health, Bethesda, MD 20892, USA
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17
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Ashton TD, Devine SM, Möhrle JJ, Laleu B, Burrows JN, Charman SA, Creek DJ, Sleebs BE. The Development Process for Discovery and Clinical Advancement of Modern Antimalarials. J Med Chem 2019; 62:10526-10562. [DOI: 10.1021/acs.jmedchem.9b00761] [Citation(s) in RCA: 40] [Impact Index Per Article: 8.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/07/2023]
Affiliation(s)
- Trent D. Ashton
- The Walter and Eliza Hall Institute of Medical Research, Parkville, Victoria 3052, Australia
- Department of Medical Biology, The University of Melbourne, Parkville, Victoria 3052, Australia
| | - Shane M. Devine
- Monash Institute of Pharmaceutical Sciences, Monash University, 381 Royal Parade, Parkville, Victoria 3052, Australia
| | - Jörg J. Möhrle
- Medicines for Malaria Venture, ICC, Route de Pré-Bois 20, 1215 Geneva, Switzerland
| | - Benoît Laleu
- Medicines for Malaria Venture, ICC, Route de Pré-Bois 20, 1215 Geneva, Switzerland
| | - Jeremy N. Burrows
- Medicines for Malaria Venture, ICC, Route de Pré-Bois 20, 1215 Geneva, Switzerland
| | - Susan A. Charman
- Monash Institute of Pharmaceutical Sciences, Monash University, 381 Royal Parade, Parkville, Victoria 3052, Australia
| | - Darren J. Creek
- Monash Institute of Pharmaceutical Sciences, Monash University, 381 Royal Parade, Parkville, Victoria 3052, Australia
| | - Brad E. Sleebs
- The Walter and Eliza Hall Institute of Medical Research, Parkville, Victoria 3052, Australia
- Department of Medical Biology, The University of Melbourne, Parkville, Victoria 3052, Australia
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18
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Bhatnagar S, Nicklas S, Morrisey JM, Goldberg DE, Vaidya AB. Diverse Chemical Compounds Target Plasmodium falciparum Plasma Membrane Lipid Homeostasis. ACS Infect Dis 2019; 5:550-558. [PMID: 30638365 DOI: 10.1021/acsinfecdis.8b00277] [Citation(s) in RCA: 11] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/06/2023]
Abstract
Lipid homeostasis is essential to the maintenance of life. We previously reported that disruptions of the parasite Na+ homeostasis via inhibition of PfATP4 resulted in elevated cholesterol within the parasite plasma membrane as assessed by saponin sensitivity. A large number of compounds have been shown to target the parasite Na+ homeostasis. We screened 800 compounds from the Malaria and Pathogen Boxes to identify chemotypes that disrupted the parasite plasma membrane lipid homeostasis. Here, we show that the compounds disrupting parasite Na+ homeostasis also induced saponin sensitivity, an indication of parasite lipid homeostasis disruption. Remarkably, 13 compounds were identified that altered the plasma membrane lipid composition independently of the Na+ homeostasis disruption. Further studies suggest that these compounds target the Plasmodium falciparum Niemann-Pick type C1-related (PfNCR1) protein, which is hypothesized to be involved in maintaining plasma membrane lipid composition. PfNCR1, like PfATP4, appears to be targeted by multiple chemotypes with the potential for drug discovery.
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Affiliation(s)
- Suyash Bhatnagar
- Center for Molecular Parasitology, Department of Microbiology and Immunology, Drexel University College of Medicine, 2900 Queen Lane, Philadelphia, Pennsylvania 19129, United States of America
| | - Sezin Nicklas
- Center for Molecular Parasitology, Department of Microbiology and Immunology, Drexel University College of Medicine, 2900 Queen Lane, Philadelphia, Pennsylvania 19129, United States of America
| | - Joanne M. Morrisey
- Center for Molecular Parasitology, Department of Microbiology and Immunology, Drexel University College of Medicine, 2900 Queen Lane, Philadelphia, Pennsylvania 19129, United States of America
| | - Daniel E. Goldberg
- Department of Medicine, Division of Infectious Diseases, Washington University School of Medicine, 4990 Children’s Place, St. Louis, Missouri 63110, United States of America
| | - Akhil B. Vaidya
- Center for Molecular Parasitology, Department of Microbiology and Immunology, Drexel University College of Medicine, 2900 Queen Lane, Philadelphia, Pennsylvania 19129, United States of America
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19
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Istvan ES, Das S, Bhatnagar S, Beck JR, Owen E, Llinas M, Ganesan SM, Niles JC, Winzeler E, Vaidya AB, Goldberg DE. Plasmodium Niemann-Pick type C1-related protein is a druggable target required for parasite membrane homeostasis. eLife 2019; 8:40529. [PMID: 30888318 PMCID: PMC6424564 DOI: 10.7554/elife.40529] [Citation(s) in RCA: 44] [Impact Index Per Article: 8.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/27/2018] [Accepted: 02/05/2019] [Indexed: 01/05/2023] Open
Abstract
Plasmodium parasites possess a protein with homology to Niemann-Pick Type C1 proteins (Niemann-Pick Type C1-Related protein, NCR1). We isolated parasites with resistance-conferring mutations in Plasmodium falciparum NCR1 (PfNCR1) during selections with three diverse small-molecule antimalarial compounds and show that the mutations are causative for compound resistance. PfNCR1 protein knockdown results in severely attenuated growth and confers hypersensitivity to the compounds. Compound treatment or protein knockdown leads to increased sensitivity of the parasite plasma membrane (PPM) to the amphipathic glycoside saponin and engenders digestive vacuoles (DVs) that are small and malformed. Immuno-electron microscopy and split-GFP experiments localize PfNCR1 to the PPM. Our experiments show that PfNCR1 activity is critically important for the composition of the PPM and is required for DV biogenesis, suggesting PfNCR1 as a novel antimalarial drug target. Editorial note: This article has been through an editorial process in which the authors decide how to respond to the issues raised during peer review. The Reviewing Editor's assessment is that all the issues have been addressed (see decision letter).
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Affiliation(s)
- Eva S Istvan
- Department of Medicine, Division of Infectious Diseases, Washington University School of Medicine, Saint Louis, United States.,Department of Molecular Microbiology, Washington University School of Medicine, Saint Louis, United States
| | - Sudipta Das
- Department of Microbiology and Immunology, Center for Molecular Parasitology, Drexel University College of Medicine, Philadelphia, United States
| | - Suyash Bhatnagar
- Department of Microbiology and Immunology, Center for Molecular Parasitology, Drexel University College of Medicine, Philadelphia, United States
| | - Josh R Beck
- Department of Medicine, Division of Infectious Diseases, Washington University School of Medicine, Saint Louis, United States.,Department of Molecular Microbiology, Washington University School of Medicine, Saint Louis, United States
| | - Edward Owen
- Department of Biochemistry and Molecular Biology, Pennsylvania State University, University Park, United States.,Huck Center for Malaria Research, Pennsylvania State University, University Park, United States.,Department of Chemistry, Pennsylvania State University, University Park, United States
| | - Manuel Llinas
- Department of Biochemistry and Molecular Biology, Pennsylvania State University, University Park, United States.,Huck Center for Malaria Research, Pennsylvania State University, University Park, United States.,Department of Chemistry, Pennsylvania State University, University Park, United States
| | - Suresh M Ganesan
- Department of Biological Engineering, Massachusetts Institute of Technology, Cambridge, United States
| | - Jacquin C Niles
- Department of Biological Engineering, Massachusetts Institute of Technology, Cambridge, United States
| | - Elizabeth Winzeler
- Department of Pediatrics, University of California San Diego School of Medicine, La Jolla, United States
| | - Akhil B Vaidya
- Department of Microbiology and Immunology, Center for Molecular Parasitology, Drexel University College of Medicine, Philadelphia, United States
| | - Daniel E Goldberg
- Department of Medicine, Division of Infectious Diseases, Washington University School of Medicine, Saint Louis, United States.,Department of Molecular Microbiology, Washington University School of Medicine, Saint Louis, United States
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20
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Antoszczak M, Steverding D, Huczyński A. Anti-parasitic activity of polyether ionophores. Eur J Med Chem 2019; 166:32-47. [DOI: 10.1016/j.ejmech.2019.01.035] [Citation(s) in RCA: 28] [Impact Index Per Article: 5.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/20/2018] [Revised: 01/08/2019] [Accepted: 01/15/2019] [Indexed: 02/04/2023]
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21
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Lehane AM, Dennis ASM, Bray KO, Li D, Rajendran E, McCoy JM, McArthur HM, Winterberg M, Rahimi F, Tonkin CJ, Kirk K, van Dooren GG. Characterization of the ATP4 ion pump in Toxoplasma gondii. J Biol Chem 2019; 294:5720-5734. [PMID: 30723156 DOI: 10.1074/jbc.ra118.006706] [Citation(s) in RCA: 11] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/13/2018] [Revised: 01/31/2019] [Indexed: 12/22/2022] Open
Abstract
The Plasmodium falciparum ATPase PfATP4 is the target of a diverse range of antimalarial compounds, including the clinical drug candidate cipargamin. PfATP4 was originally annotated as a Ca2+ transporter, but recent evidence suggests that it is a Na+ efflux pump, extruding Na+ in exchange for H+ Here we demonstrate that ATP4 proteins belong to a clade of P-type ATPases that are restricted to apicomplexans and their closest relatives. We employed a variety of genetic and physiological approaches to investigate the ATP4 protein of the apicomplexan Toxoplasma gondii, TgATP4. We show that TgATP4 is a plasma membrane protein. Knockdown of TgATP4 had no effect on resting pH or Ca2+ but rendered parasites unable to regulate their cytosolic Na+ concentration ([Na+]cyt). PfATP4 inhibitors caused an increase in [Na+]cyt and a cytosolic alkalinization in WT but not TgATP4 knockdown parasites. Parasites in which TgATP4 was knocked down or disrupted exhibited a growth defect, attributable to reduced viability of extracellular parasites. Parasites in which TgATP4 had been disrupted showed reduced virulence in mice. These results provide evidence for ATP4 proteins playing a key conserved role in Na+ regulation in apicomplexan parasites.
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Affiliation(s)
- Adele M Lehane
- From the Research School of Biology, Australian National University, Canberra, ACT 2601, Australia,
| | - Adelaide S M Dennis
- From the Research School of Biology, Australian National University, Canberra, ACT 2601, Australia
| | - Katherine O Bray
- From the Research School of Biology, Australian National University, Canberra, ACT 2601, Australia
| | - Dongdi Li
- From the Research School of Biology, Australian National University, Canberra, ACT 2601, Australia
| | - Esther Rajendran
- From the Research School of Biology, Australian National University, Canberra, ACT 2601, Australia
| | - James M McCoy
- the Walter and Eliza Hall Institute of Medical Research, Melbourne, VIC 3052, Australia, and.,the Department of Medical Biology, University of Melbourne, Melbourne, VIC 3010, Australia
| | - Hillary M McArthur
- From the Research School of Biology, Australian National University, Canberra, ACT 2601, Australia
| | - Markus Winterberg
- From the Research School of Biology, Australian National University, Canberra, ACT 2601, Australia
| | - Farid Rahimi
- From the Research School of Biology, Australian National University, Canberra, ACT 2601, Australia
| | - Christopher J Tonkin
- the Walter and Eliza Hall Institute of Medical Research, Melbourne, VIC 3052, Australia, and.,the Department of Medical Biology, University of Melbourne, Melbourne, VIC 3010, Australia
| | - Kiaran Kirk
- From the Research School of Biology, Australian National University, Canberra, ACT 2601, Australia,
| | - Giel G van Dooren
- From the Research School of Biology, Australian National University, Canberra, ACT 2601, Australia,
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22
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Rebello KM, Andrade-Neto VV, Zuma AA, Motta MCM, Gomes CRB, de Souza MVN, Atella GC, Branquinha MH, Santos ALS, Torres-Santos EC, d'Avila-Levy CM. Lopinavir, an HIV-1 peptidase inhibitor, induces alteration on the lipid metabolism of Leishmania amazonensis promastigotes. Parasitology 2018; 145:1304-1310. [PMID: 29806577 PMCID: PMC6137378 DOI: 10.1017/s0031182018000823] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/08/2018] [Revised: 04/03/2018] [Accepted: 04/05/2018] [Indexed: 12/11/2022]
Abstract
The anti-leishmania effects of HIV peptidase inhibitors (PIs) have been widely reported; however, the biochemical target and mode of action are still a matter of controversy in Leishmania parasites. Considering the possibility that HIV-PIs induce lipid accumulation in Leishmania amazonensis, we analysed the effects of lopinavir on the lipid metabolism of L. amazonensis promastigotes. To this end, parasites were treated with lopinavir at different concentrations and analysed by fluorescence microscopy and spectrofluorimetry, using a fluorescent lipophilic marker. Then, the cellular ultrastructure of treated and control parasites was analysed by transmission electron microscopy (TEM), and the lipid composition was investigated by thin-layer chromatography (TLC). Finally, the sterol content was assayed by gas chromatography-mass spectrometry (GC/MS). TEM analysis revealed an increased number of lipid inclusions in lopinavir-treated cells, which was accompanied by an increase in the lipophilic content, in a dose-dependent manner. TLC and GC-MS analysis revealed a marked increase of cholesterol-esters and cholesterol. In conclusion, lopinavir-induced lipid accumulation and affected lipid composition in L. amazonensis in a concentration-response manner. These data contribute to a better understanding of the possible mechanisms of action of this HIV-PI in L. amazonensis promastigotes. The concerted action of lopinavir on this and other cellular processes, such as the direct inhibition of an aspartyl peptidase, may be responsible for the arrested development of the parasite.
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Affiliation(s)
- Karina M Rebello
- Laboratório de Estudos Integrados em Protozoologia,Instituto Oswaldo Cruz, Fundação Oswaldo Cruz (FIOCRUZ),Rio de Janeiro,Brazil
| | - Valter V Andrade-Neto
- Laboratório de Bioquímica de Tripanosomatídeos,Instituto Oswaldo Cruz, FIOCRUZ,Rio de Janeiro,Brazil
| | - Aline A Zuma
- Laboratório de Ultraestrutura Celular Hertha Meyer,Instituto de Biofísica Carlos Chagas Filho, Universidade Federal do Rio de Janeiro (UFRJ),Rio de Janeiro,Brazil
| | - Maria Cristina M Motta
- Laboratório de Ultraestrutura Celular Hertha Meyer,Instituto de Biofísica Carlos Chagas Filho, Universidade Federal do Rio de Janeiro (UFRJ),Rio de Janeiro,Brazil
| | | | | | | | - Marta H Branquinha
- Laboratório de Investigação de Peptidases,Instituto de Microbiologia Paulo de Góes, UFRJ,Rio de Janeiro,Brazil
| | - André L S Santos
- Laboratório de Investigação de Peptidases,Instituto de Microbiologia Paulo de Góes, UFRJ,Rio de Janeiro,Brazil
| | | | - Claudia M d'Avila-Levy
- Laboratório de Estudos Integrados em Protozoologia,Instituto Oswaldo Cruz, Fundação Oswaldo Cruz (FIOCRUZ),Rio de Janeiro,Brazil
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23
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Raza M, Bharti H, Singal A, Nag A, Ghosh PC. Long circulatory liposomal maduramicin inhibits the growth of Plasmodium falciparum blood stages in culture and cures murine models of experimental malaria. NANOSCALE 2018; 10:13773-13791. [PMID: 29995025 DOI: 10.1039/c8nr02442a] [Citation(s) in RCA: 20] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/08/2023]
Abstract
Malaria continues to be one of the deadliest infectious diseases and a global health menace. The emergence and spread of drug-resistant strains of malaria parasites have further made the process of disease management grimmer. Thus, there is an urgent need to identify promising antimalarial strategies that can target the blood stages as well as block parasite transmission. Maduramicin is one such ionophore selected out of a recent screen of gametocytocidal compounds that exhibit potent antiplasmodial activity. However, maduramicin's strong hydrophobic nature and associated toxicity restrict its application in chemotherapy. To alleviate this problem, we have developed a liposomal formulation loaded with the ionophore maduramicin for the treatment of chloroquine sensitive and resistant Plasmodium infections. Here, we show that maduramicin in PEGylated liposomal formulations displayed enhanced antiplasmodial activity in vitro compared to free maduramicin. Significantly, four consecutive doses of 1.5 mg kg-1 body weight of PEGylated maduramicin loaded lipid vesicles completely cured cerebral and chloroquine resistant murine models of malaria without any obvious toxic effects and suppressed the key inflammatory markers associated with the progression of the disease. PEGylated liposomal maduramicin also exhibited a prolonged plasma clearance rate, implying a greater chance of interaction and uptake by infected RBCs. Furthermore, we also provide evidence that the detrimental effect of liposomal maduramicin on parasite survival is mediated by increased ROS generation and subsequent perturbation of parasite mitochondrial membrane potential. This study presents the first report to demonstrate the potent antimalarial efficacy of maduramicin liposomes, a strategy that holds promise for the development of successful therapeutic intervention against malaria in humans.
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Affiliation(s)
- Mohsin Raza
- Department of Biochemistry, University of Delhi South Campus, Benito Juarez Road, New Delhi-110021, India.
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24
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Dennis ASM, Rosling JEO, Lehane AM, Kirk K. Diverse antimalarials from whole-cell phenotypic screens disrupt malaria parasite ion and volume homeostasis. Sci Rep 2018; 8:8795. [PMID: 29892073 PMCID: PMC5995868 DOI: 10.1038/s41598-018-26819-1] [Citation(s) in RCA: 24] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/14/2017] [Accepted: 05/14/2018] [Indexed: 11/17/2022] Open
Abstract
Four hundred structurally diverse drug-like compounds comprising the Medicines for Malaria Venture's 'Pathogen Box' were screened for their effect on a range of physiological parameters in asexual blood-stage malaria (Plasmodium falciparum) parasites. Eleven of these compounds were found to perturb parasite Na+, pH and volume in a manner consistent with inhibition of the putative Na+ efflux P-type ATPase PfATP4. All eleven compounds fell within the subset of 125 compounds included in the Pathogen Box on the basis of their having been identified as potent inhibitors of the growth of asexual blood-stage P. falciparum parasites. All eleven compounds inhibited the Na+-dependent ATPase activity of parasite membranes and showed reduced efficacy against parasites carrying mutations in PfATP4. This study increases the number of chemically diverse structures known to show a 'PfATP4-associated' phenotype, and adds to emerging evidence that a high proportion (7-9%) of the structurally diverse antimalarial compounds identified in whole cell phenotypic screens share the same mechanism of action, exerting their antimalarial effect via an interaction with PfATP4.
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Affiliation(s)
- Adelaide S M Dennis
- Research School of Biology, Australian National University, Canberra, ACT 2601, Australia
| | - James E O Rosling
- Research School of Biology, Australian National University, Canberra, ACT 2601, Australia
| | - Adele M Lehane
- Research School of Biology, Australian National University, Canberra, ACT 2601, Australia.
| | - Kiaran Kirk
- Research School of Biology, Australian National University, Canberra, ACT 2601, Australia.
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Cell Swelling Induced by the Antimalarial KAE609 (Cipargamin) and Other PfATP4-Associated Antimalarials. Antimicrob Agents Chemother 2018; 62:AAC.00087-18. [PMID: 29555632 DOI: 10.1128/aac.00087-18] [Citation(s) in RCA: 23] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/16/2018] [Accepted: 02/18/2018] [Indexed: 12/15/2022] Open
Abstract
For an increasing number of antimalarial agents identified in high-throughput phenotypic screens, there is evidence that they target PfATP4, a putative Na+ efflux transporter on the plasma membrane of the human malaria parasite Plasmodium falciparum For several such "PfATP4-associated" compounds, it has been noted that their addition to parasitized erythrocytes results in cell swelling. Here we show that six structurally diverse PfATP4-associated compounds, including the clinical candidate KAE609 (cipargamin), induce swelling of both isolated blood-stage parasites and intact parasitized erythrocytes. The swelling of isolated parasites is dependent on the presence of Na+ in the external environment and may be attributed to the osmotic consequences of Na+ uptake. The swelling of the parasitized erythrocyte results in an increase in its osmotic fragility. Countering cell swelling by increasing the osmolarity of the extracellular medium reduces the antiplasmodial efficacy of PfATP4-associated compounds, consistent with cell swelling playing a role in the antimalarial activity of this class of compounds.
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26
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Ke H, Dass S, Morrisey JM, Mather MW, Vaidya AB. The mitochondrial ribosomal protein L13 is critical for the structural and functional integrity of the mitochondrion in Plasmodium falciparum. J Biol Chem 2018; 293:8128-8137. [PMID: 29626096 DOI: 10.1074/jbc.ra118.002552] [Citation(s) in RCA: 34] [Impact Index Per Article: 5.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/20/2018] [Revised: 04/02/2018] [Indexed: 12/22/2022] Open
Abstract
The phylum Apicomplexa contains a group of protozoa causing diseases in humans and livestock. Plasmodium spp., the causative agent of malaria, contains a mitochondrion that is very divergent from that of their hosts. The malarial mitochondrion is a clinically validated target for the antimalarial drug atovaquone, which specifically blocks the electron transfer activity of the bc1 complex of the mitochondrial electron transport chain (mtETC). Most mtETC proteins are nuclear-encoded and imported from the cytosol, but three key protein subunits are encoded in the Plasmodium mitochondrial genome: cyt b, COXI, and COXIII. They are translated inside the mitochondrion by mitochondrial ribosomes (mitoribosomes). Here, we characterize the function of one large mitoribosomal protein in Plasmodium falciparum, PfmRPL13. We found that PfmRPL13 localizes to the parasite mitochondrion and is refractory to genetic knockout. Ablation of PfmRPL13 using a conditional knockdown system (TetR-DOZI-aptamer) caused a series of adverse events in the parasite, including mtETC deficiency, loss of mitochondrial membrane potential (Δψm), and death. The PfmRPL13 knockdown parasite also became hypersensitive to proguanil, a drug proposed to target an alternative process for maintaining Δψm Surprisingly, transmission EM revealed that PfmRPL13 disruption also resulted in an unusually elongated and branched mitochondrion. The growth arrest of the knockdown parasite could be rescued with a second copy of PfmRPL13, but not by supplementation with decylubiquinone or addition of a yeast dihydroorotate dehydrogenase gene. In summary, we provide first and direct evidence that mitoribosomes are essential for malaria parasites to maintain the structural and functional integrity of the mitochondrion.
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Affiliation(s)
- Hangjun Ke
- Center for Molecular Parasitology, Department of Microbiology and Immunology, Drexel University College of Medicine, Philadelphia, Pennsylvania 19129.
| | - Swati Dass
- Center for Molecular Parasitology, Department of Microbiology and Immunology, Drexel University College of Medicine, Philadelphia, Pennsylvania 19129
| | - Joanne M Morrisey
- Center for Molecular Parasitology, Department of Microbiology and Immunology, Drexel University College of Medicine, Philadelphia, Pennsylvania 19129
| | - Michael W Mather
- Center for Molecular Parasitology, Department of Microbiology and Immunology, Drexel University College of Medicine, Philadelphia, Pennsylvania 19129
| | - Akhil B Vaidya
- Center for Molecular Parasitology, Department of Microbiology and Immunology, Drexel University College of Medicine, Philadelphia, Pennsylvania 19129
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27
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Abstract
Malaria is caused in humans by five species of single-celled eukaryotic Plasmodium parasites (mainly Plasmodium falciparum and Plasmodium vivax) that are transmitted by the bite of Anopheles spp. mosquitoes. Malaria remains one of the most serious infectious diseases; it threatens nearly half of the world's population and led to hundreds of thousands of deaths in 2015, predominantly among children in Africa. Malaria is managed through a combination of vector control approaches (such as insecticide spraying and the use of insecticide-treated bed nets) and drugs for both treatment and prevention. The widespread use of artemisinin-based combination therapies has contributed to substantial declines in the number of malaria-related deaths; however, the emergence of drug resistance threatens to reverse this progress. Advances in our understanding of the underlying molecular basis of pathogenesis have fuelled the development of new diagnostics, drugs and insecticides. Several new combination therapies are in clinical development that have efficacy against drug-resistant parasites and the potential to be used in single-dose regimens to improve compliance. This ambitious programme to eliminate malaria also includes new approaches that could yield malaria vaccines or novel vector control strategies. However, despite these achievements, a well-coordinated global effort on multiple fronts is needed if malaria elimination is to be achieved.
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Affiliation(s)
- Margaret A Phillips
- Department of Biochemistry, University of Texas Southwestern Medical Center at Dallas, 5323 Harry Hines Boulevard, Dallas, Texas 75390-9038, USA
| | | | | | | | - Wesley C Van Voorhis
- University of Washington, Department of Medicine, Division of Allergy and Infectious Diseases, Center for Emerging and Re-emerging Infectious Diseases, Seattle, Washington, USA
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28
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Metabolomic Profiling of the Malaria Box Reveals Antimalarial Target Pathways. Antimicrob Agents Chemother 2016; 60:6635-6649. [PMID: 27572391 DOI: 10.1128/aac.01224-16] [Citation(s) in RCA: 108] [Impact Index Per Article: 13.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/10/2016] [Accepted: 08/16/2016] [Indexed: 12/11/2022] Open
Abstract
The threat of widespread drug resistance to frontline antimalarials has renewed the urgency for identifying inexpensive chemotherapeutic compounds that are effective against Plasmodium falciparum, the parasite species responsible for the greatest number of malaria-related deaths worldwide. To aid in the fight against malaria, a recent extensive screening campaign has generated thousands of lead compounds with low micromolar activity against blood stage parasites. A subset of these leads has been compiled by the Medicines for Malaria Venture (MMV) into a collection of structurally diverse compounds known as the MMV Malaria Box. Currently, little is known regarding the activity of these Malaria Box compounds on parasite metabolism during intraerythrocytic development, and a majority of the targets for these drugs have yet to be defined. Here we interrogated the in vitro metabolic effects of 189 drugs (including 169 of the drug-like compounds from the Malaria Box) using ultra-high-performance liquid chromatography-mass spectrometry (UHPLC-MS). The resulting metabolic fingerprints provide information on the parasite biochemical pathways affected by pharmacologic intervention and offer a critical blueprint for selecting and advancing lead compounds as next-generation antimalarial drugs. Our results reveal several major classes of metabolic disruption, which allow us to predict the mode of action (MoA) for many of the Malaria Box compounds. We anticipate that future combination therapies will be greatly informed by these results, allowing for the selection of appropriate drug combinations that simultaneously target multiple metabolic pathways, with the aim of eliminating malaria and forestalling the expansion of drug-resistant parasites in the field.
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