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Simmons C, Gibbons J, Wang C, Pires CV, Zhang M, Siddiqui F, Oberstaller J, Casandra D, Seyfang A, Cui L, Otto TD, Adams JH. A novel Modulator of Ring Stage Translation (MRST) gene alters artemisinin sensitivity in Plasmodium falciparum. mSphere 2023; 8:e0015223. [PMID: 37219373 PMCID: PMC10449512 DOI: 10.1128/msphere.00152-23] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/25/2023] [Accepted: 04/18/2023] [Indexed: 05/24/2023] Open
Abstract
The implementation of artemisinin (ART) combination therapies (ACTs) has greatly decreased deaths caused by Plasmodium falciparum malaria, but increasing ACT resistance in Southeast Asia and Africa could reverse this progress. Parasite population genetic studies have identified numerous genes, single-nucleotide polymorphisms (SNPs), and transcriptional signatures associated with altered artemisinin activity with SNPs in the Kelch13 (K13) gene being the most well-characterized artemisinin resistance marker. However, there is an increasing evidence that resistance to artemisinin in P. falciparum is not related only to K13 SNPs, prompting the need to characterize other novel genes that can alter ART responses in P. falciparum. In our previous analyses of P. falciparum piggyBac mutants, several genes of unknown function exhibited increased sensitivity to artemisinin that was similar to a mutant of K13. Further analysis of these genes and their gene co-expression networks indicated that the ART sensitivity cluster was functionally linked to DNA replication and repair, stress responses, and maintenance of homeostatic nuclear activity. In this study, we have characterized PF3D7_1136600, another member of the ART sensitivity cluster. Previously annotated as a conserved Plasmodium gene of unknown function, we now provide putative annotation of this gene as a Modulator of Ring Stage Translation (MRST). Our findings reveal that the mutagenesis of MRST affects gene expression of multiple translation-associated pathways during the early ring stage of asexual development via putative ribosome assembly and maturation activity, suggesting an essential role of MRST in protein biosynthesis and another novel mechanism of altering the parasite's ART drug response.IMPORTANCEPlasmodium falciparum malaria killed more than 600,000 people in 2021, though ACTs have been critical in reducing malaria mortality as a first-line treatment for infection. However, ACT resistance in Southeast Asia and emerging resistance in Africa are detrimental to this progress. Mutations to Kelch13 (K13) have been identified to confer increased artemisinin tolerance in field isolates, however, genes other than K13 are implicated in altering how the parasite responds to artemisinin prompts additional analysis. Therefore, in this study we have characterized a P. falciparum mutant clone with altered sensitivity to artemisinin and identified a novel gene (PF3D7_1136600) that is associated with alterations to parasite translational metabolism during critical timepoints for artemisinin drug response. Many genes of the P. falciparum genome remain unannotated, posing a challenge for drug-gene characterizations in the parasite. Therefore, through this study, we have putatively annotated PF3D7_1136600 as a novel MRST gene and have identified a potential link between MRST and parasite stress response mechanisms.
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Affiliation(s)
- Caroline Simmons
- Center for Global Health and Infectious Diseases Research and USF Genomics Program, 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
| | - Justin Gibbons
- Center for Global Health and Infectious Diseases Research and USF Genomics Program, College of Public Health, University of South Florida, Tampa, Florida, USA
| | - Chengqi Wang
- Center for Global Health and Infectious Diseases Research and USF Genomics Program, College of Public Health, University of South Florida, Tampa, Florida, USA
| | - Camilla Valente Pires
- Center for Global Health and Infectious Diseases Research and USF Genomics Program, College of Public Health, University of South Florida, Tampa, Florida, USA
| | - Min Zhang
- Center for Global Health and Infectious Diseases Research and USF Genomics Program, College of Public Health, University of South Florida, Tampa, Florida, USA
| | - Faiza Siddiqui
- Center for Global Health and Infectious Diseases Research and USF Genomics Program, College of Public Health, University of South Florida, Tampa, Florida, USA
| | - Jenna Oberstaller
- Center for Global Health and Infectious Diseases Research and USF Genomics Program, College of Public Health, University of South Florida, Tampa, Florida, USA
| | - Debora Casandra
- Center for Global Health and Infectious Diseases Research and USF Genomics Program, College of Public Health, University of South Florida, Tampa, Florida, USA
| | - Andreas Seyfang
- Center for Global Health and Infectious Diseases Research and USF Genomics Program, 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
| | - Liwang Cui
- Center for Global Health and Infectious Diseases Research and USF Genomics Program, College of Public Health, University of South Florida, Tampa, Florida, USA
- Department of Internal Medicine, Morsani College of Medicine, University of South Florida, Tampa, Florida, USA
| | - Thomas D. Otto
- Institute of Infection, Immunity, and Inflammation, College of Medical, Veterinary and Life Sciences, University of Glasgow, Glasgow, UK
| | - John H. Adams
- Center for Global Health and Infectious Diseases Research and USF Genomics Program, College of Public Health, University of South Florida, Tampa, Florida, USA
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Owoloye A, Olufemi M, Idowu ET, Oyebola KM. Prevalence of potential mediators of artemisinin resistance in African isolates of Plasmodium falciparum. Malar J 2021; 20:451. [PMID: 34856982 PMCID: PMC8638531 DOI: 10.1186/s12936-021-03987-6] [Citation(s) in RCA: 18] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/07/2021] [Accepted: 11/16/2021] [Indexed: 11/30/2022] Open
Abstract
Background The devastating public health impact of malaria has prompted the need for effective interventions. Malaria control gained traction after the introduction of artemisinin-based combination therapy (ACT). However, the emergence of artemisinin (ART) partial resistance in Southeast Asia and emerging reports of delayed parasite sensitivity to ACT in African parasites signal a gradual trend towards treatment failure. Monitoring the prevalence of mutations associated with artemisinin resistance in African populations is necessary to stop resistance in its tracks. Mutations in Plasmodium falciparum genes pfk13, pfcoronin and pfatpase6 have been linked with ART partial resistance. Methods Findings from published research articles on the prevalence of pfk13, pfcoronin and pfatpase6 polymorphisms in Africa were collated. PubMed, Embase and Google Scholar were searched for relevant articles reporting polymorphisms in these genes across Africa from 2014 to August 2021, for pfk13 and pfcoronin. For pfatpase6, relevant articles between 2003 and August 2021 were retrieved. Results Eighty-seven studies passed the inclusion criteria for this analysis and reported 742 single nucleotide polymorphisms in 37,864 P. falciparum isolates from 29 African countries. Five validated-pfk13 partial resistance markers were identified in Africa: R561H in Rwanda and Tanzania, M476I in Tanzania, F446I in Mali, C580Y in Ghana, and P553L in an Angolan isolate. In Tanzania, three (L263E, E431K, S769N) of the four mutations (L263E, E431K, A623E, S769N) in pfatpase6 gene associated with high in vitro IC50 were reported. pfcoronin polymorphisms were reported in Senegal, Gabon, Ghana, Kenya, and Congo, with P76S being the most prevalent mutation. Conclusions This meta-analysis provides an overview of the prevalence and widespread distribution of pfk13, pfcoronin and pfatpase6 mutations in Africa. Understanding the phenotypic consequences of these mutations can provide information on the efficacy status of artemisinin-based treatment of malaria across the continent. Graphical Abstract ![]()
Supplementary Information The online version contains supplementary material available at 10.1186/s12936-021-03987-6.
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Affiliation(s)
- Afolabi Owoloye
- Genomic Research in Biomedicine Laboratory, Biochemistry and Nutrition Department, Nigerian Institute of Medical Research, Lagos, Nigeria.,Parasitology and Bioinformatics Unit, Department of Zoology, Faculty of Science, University of Lagos, Lagos, Nigeria
| | - Michael Olufemi
- Genomic Research in Biomedicine Laboratory, Biochemistry and Nutrition Department, Nigerian Institute of Medical Research, Lagos, Nigeria.,Parasitology and Bioinformatics Unit, Department of Zoology, Faculty of Science, University of Lagos, Lagos, Nigeria
| | - Emmanuel T Idowu
- Parasitology and Bioinformatics Unit, Department of Zoology, Faculty of Science, University of Lagos, Lagos, Nigeria
| | - Kolapo M Oyebola
- Genomic Research in Biomedicine Laboratory, Biochemistry and Nutrition Department, Nigerian Institute of Medical Research, Lagos, Nigeria. .,Parasitology and Bioinformatics Unit, Department of Zoology, Faculty of Science, University of Lagos, Lagos, Nigeria. .,Sickle Cell Branch, National Heart Lung and Blood Institute, US National Institutes of Health, Bethesda, MD, USA.
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Behrens HM, Schmidt S, Spielmann T. The newly discovered role of endocytosis in artemisinin resistance. Med Res Rev 2021; 41:2998-3022. [PMID: 34309894 DOI: 10.1002/med.21848] [Citation(s) in RCA: 10] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/30/2020] [Revised: 04/15/2021] [Accepted: 07/03/2021] [Indexed: 12/28/2022]
Abstract
Artemisinin and its derivatives (ART) are the cornerstone of malaria treatment as part of artemisinin combination therapy (ACT). However, reduced susceptibility to artemisinin as well as its partner drugs threatens the usefulness of ACTs. Single point mutations in the parasite protein Kelch13 (K13) are necessary and sufficient for the reduced sensitivity of malaria parasites to ART but several alternative mechanisms for this resistance have been proposed. Recent work found that K13 is involved in the endocytosis of host cell cytosol and indicated that this is the process responsible for resistance in parasites with mutated K13. These studies also identified a series of further proteins that act together with K13 in the same pathway, including previously suspected resistance proteins such as UBP1 and AP-2μ. Here, we give a brief overview of artemisinin resistance, present the recent evidence of the role of endocytosis in ART resistance and discuss previous hypotheses in light of this new evidence. We also give an outlook on how the new insights might affect future research.
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Affiliation(s)
- Hannah Michaela Behrens
- Molecular Biology and Immunology Section, Bernhard Nocht Institute for Tropical Medicine, Hamburg, Germany
| | - Sabine Schmidt
- Molecular Biology and Immunology Section, Bernhard Nocht Institute for Tropical Medicine, Hamburg, Germany
| | - Tobias Spielmann
- Molecular Biology and Immunology Section, Bernhard Nocht Institute for Tropical Medicine, Hamburg, Germany
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Sutherland CJ, Henrici RC, Artavanis-Tsakonas K. Artemisinin susceptibility in the malaria parasite Plasmodium falciparum: propellers, adaptor proteins and the need for cellular healing. FEMS Microbiol Rev 2021; 45:fuaa056. [PMID: 33095255 PMCID: PMC8100002 DOI: 10.1093/femsre/fuaa056] [Citation(s) in RCA: 18] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/25/2020] [Accepted: 10/21/2020] [Indexed: 12/12/2022] Open
Abstract
Studies of the susceptibility of Plasmodium falciparum to the artemisinin family of antimalarial drugs provide a complex picture of partial resistance (tolerance) associated with increased parasite survival in vitro and in vivo. We present an overview of the genetic loci that, in mutant form, can independently elicit parasite tolerance. These encode Kelch propeller domain protein PfK13, ubiquitin hydrolase UBP-1, actin filament-organising protein Coronin, also carrying a propeller domain, and the trafficking adaptor subunit AP-2μ. Detailed studies of these proteins and the functional basis of artemisinin tolerance in blood-stage parasites are enabling a new synthesis of our understanding to date. To guide further experimental work, we present two major conclusions. First, we propose a dual-component model of artemisinin tolerance in P. falciparum comprising suppression of artemisinin activation in early ring stage by reducing endocytic haemoglobin capture from host cytosol, coupled with enhancement of cellular healing mechanisms in surviving cells. Second, these two independent requirements limit the likelihood of development of complete artemisinin resistance by P. falciparum, favouring deployment of existing drugs in new schedules designed to exploit these biological limits, thus extending the useful life of current combination therapies.
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Affiliation(s)
- Colin J Sutherland
- Department of Infection Biology, Faculty of Infectious and Tropical Diseases, London School of Hygiene and Tropical Medicine, Keppel St, London WC1E 7HT, UK
| | - Ryan C Henrici
- Department of Infection Biology, Faculty of Infectious and Tropical Diseases, London School of Hygiene and Tropical Medicine, Keppel St, London WC1E 7HT, UK
- Center for Global Health, Perelman School of Medicine, University of Pennsylvania, Philadelphia 19104, PA, USA
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Kayiba NK, Yobi DM, Tshibangu-Kabamba E, Tuan VP, Yamaoka Y, Devleesschauwer B, Mvumbi DM, Okitolonda Wemakoy E, De Mol P, Mvumbi GL, Hayette MP, Rosas-Aguirre A, Speybroeck N. Spatial and molecular mapping of Pfkelch13 gene polymorphism in Africa in the era of emerging Plasmodium falciparum resistance to artemisinin: a systematic review. THE LANCET. INFECTIOUS DISEASES 2020; 21:e82-e92. [PMID: 33125913 DOI: 10.1016/s1473-3099(20)30493-x] [Citation(s) in RCA: 34] [Impact Index Per Article: 8.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/14/2019] [Revised: 03/29/2020] [Accepted: 04/21/2020] [Indexed: 12/19/2022]
Abstract
The spread of Plasmodium falciparum isolates carrying mutations in the kelch13 (Pfkelch13) gene associated with artemisinin resistance (PfART-R) in southeast Asia threatens malaria control and elimination efforts. Emergence of PfART-R in Africa would result in a major public health problem. In this systematic review, we investigate the frequency and spatial distribution of Pfkelch13 mutants in Africa, including mutants linked to PfART-R in southeast Asia. Seven databases were searched (PubMed, Embase, Scopus, African Journal Online, African Index Medicus, Bioline, and Web of Science) for relevant articles about polymorphisms of the Pfkelch13 gene in Africa before January, 2019. Following PRISMA guidelines, 53 studies that sequenced the Pfkelch13 gene of 23 100 sample isolates in 41 sub-Saharan African countries were included. The Pfkelch13 sequence was highly polymorphic (292 alleles, including 255 in the Pfkelch13-propeller domain) but with mutations occurring at very low relative frequencies. Non-synonymous mutations were found in only 626 isolates (2·7%) from west, central, and east Africa. According to WHO, nine different mutations linked to PfART-R in southeast Asia (Phe446Ile, Cys469Tyr, Met476Ile, Arg515Lys, Ser522Cys, Pro553Leu, Val568Gly, Pro574Leu, and Ala675Val) were detected, mainly in east Africa. Several other Pfkelch13 mutations, such as those structurally similar to southeast Asia PfART-R mutations, were also identified, but their relevance for drug resistance is still unknown. This systematic review shows that Africa, thought to not have established PfART-R, reported resistance-related mutants in the past 5 years. Surveillance using PfART-R molecular markers can provide valuable decision-making information to sustain the effectiveness of artemisinin in Africa.
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Affiliation(s)
- Nadine K Kayiba
- Institute of Health and Society, Université catholique de Louvain, Brussels, Belgium; Department of Public Health, University of Mbujimayi, Mbujimayi, DR Congo; Department of Epidemiology and Biostatistics, University of Kinshasa, Kinshasa, DR Congo
| | - Doudou M Yobi
- Department of Basic Sciences, University of Kinshasa, Kinshasa, DR Congo
| | - Evariste Tshibangu-Kabamba
- Department of Basic Sciences, University of Mbujimayi, Mbujimayi, DR Congo; Department of Environmental and Preventive Medicine, Oita University, Yufu, Japan
| | - Vo P Tuan
- Department of Endoscopy, Cho Ray Hospital, Ho Chi Minh, Vietnam; Department of Environmental and Preventive Medicine, Oita University, Yufu, Japan
| | - Yoshio Yamaoka
- Department of Environmental and Preventive Medicine, Oita University, Yufu, Japan
| | - Brecht Devleesschauwer
- Department of Epidemiology and Public Health, Sciensano, Brussels, Belgium; Department of Veterinary Public Health and Food Safety, Ghent University, Merelbeke, Belgium
| | - Dieudonné M Mvumbi
- Department of Basic Sciences, University of Kinshasa, Kinshasa, DR Congo
| | | | - Patrick De Mol
- Department of Parasitology and Mycology, University Hospital of Liège, Liège, Belgium
| | - Georges L Mvumbi
- Department of Basic Sciences, University of Kinshasa, Kinshasa, DR Congo
| | - Marie-Pierre Hayette
- Department of Parasitology and Mycology, University Hospital of Liège, Liège, Belgium
| | - Angel Rosas-Aguirre
- Institute of Health and Society, Université catholique de Louvain, Brussels, Belgium
| | - Niko Speybroeck
- Institute of Health and Society, Université catholique de Louvain, Brussels, Belgium.
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Diallo MA, Yade MS, Ndiaye YD, Diallo I, Diongue K, Sy SA, Sy M, Seck MC, Ndiaye M, Dieye B, Gomis JF, Sow D, Dème AB, Badiane AS, Ndiaye D. Efficacy and safety of artemisinin-based combination therapy and the implications of Pfkelch13 and Pfcoronin molecular markers in treatment failure in Senegal. Sci Rep 2020; 10:8907. [PMID: 32483161 PMCID: PMC7264303 DOI: 10.1038/s41598-020-65553-5] [Citation(s) in RCA: 15] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/02/2020] [Accepted: 04/30/2020] [Indexed: 12/02/2022] Open
Abstract
In 2006, Senegal adopted artemisinin-based combination therapy (ACT) as first-line treatment in the management of uncomplicated malaria. This study aimed to update the status of antimalarial efficacy more than ten years after their first introduction. This was a randomized, three-arm, open-label study to evaluate the efficacy and safety of artemether-lumefantrine (AL), artesunate-amodiaquine (ASAQ) and dihydroartemisinin-piperaquine (DP) in Senegal. Malaria suspected patients were screened, enrolled, treated, and followed for 28 days for AL and ASAQ arms or 42 days for DP arm. Clinical and parasitological responses were assessed following antimalarial treatment. Genotyping (msp1, msp2 and 24 SNP-based barcode) were done to differentiate recrudescence from re-infection; in case of PCR-confirmed treatment failure, Pfk13 propeller and Pfcoronin genes were sequenced. Data was entered and analyzed using the WHO Excel-based application. A total of 496 patients were enrolled. In Diourbel, PCR non-corrected/corrected adequate clinical and parasitological responses (ACPR) was 100.0% in both the AL and ASAQ arms. In Kedougou, PCR corrected ACPR values were 98.8%, 100% and 97.6% in AL, ASAQ and DP arms respectively. No Pfk13 or Pfcoronin mutations associated with artemisinin resistance were found. This study showed that AL, ASAQ and DP remain efficacious and well-tolerated in the treatment of uncomplicated P. falciparum malaria in Senegal.
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Affiliation(s)
- Mamadou Alpha Diallo
- Department of Parasitology and Mycology, Cheikh Anta Diop University, Avenue Cheikh Anta Diop, BP 5005 Fann, Dakar, Senegal.
| | - Mamadou Samb Yade
- Department of Parasitology and Mycology, Cheikh Anta Diop University, Avenue Cheikh Anta Diop, BP 5005 Fann, Dakar, Senegal
| | - Yaye Die Ndiaye
- Department of Parasitology and Mycology, Cheikh Anta Diop University, Avenue Cheikh Anta Diop, BP 5005 Fann, Dakar, Senegal
| | - Ibrahima Diallo
- National Malaria Control Program (NMCP), Rue Aimé Césaire, Fann Résidence, Dakar, Senegal
| | - Khadim Diongue
- Department of Parasitology and Mycology, Cheikh Anta Diop University, Avenue Cheikh Anta Diop, BP 5005 Fann, Dakar, Senegal
| | - Saidou Abdoul Sy
- Department of Parasitology and Mycology, Cheikh Anta Diop University, Avenue Cheikh Anta Diop, BP 5005 Fann, Dakar, Senegal
| | - Mouhamad Sy
- Department of Parasitology and Mycology, Cheikh Anta Diop University, Avenue Cheikh Anta Diop, BP 5005 Fann, Dakar, Senegal
| | - Mame Cheikh Seck
- Department of Parasitology and Mycology, Cheikh Anta Diop University, Avenue Cheikh Anta Diop, BP 5005 Fann, Dakar, Senegal
| | - Mouhamadou Ndiaye
- Department of Parasitology and Mycology, Cheikh Anta Diop University, Avenue Cheikh Anta Diop, BP 5005 Fann, Dakar, Senegal
| | - Baba Dieye
- Department of Parasitology and Mycology, Cheikh Anta Diop University, Avenue Cheikh Anta Diop, BP 5005 Fann, Dakar, Senegal
| | - Jules François Gomis
- Department of Parasitology and Mycology, Cheikh Anta Diop University, Avenue Cheikh Anta Diop, BP 5005 Fann, Dakar, Senegal
| | - Djiby Sow
- Department of Parasitology and Mycology, Cheikh Anta Diop University, Avenue Cheikh Anta Diop, BP 5005 Fann, Dakar, Senegal
| | - Awa Bineta Dème
- Department of Parasitology and Mycology, Cheikh Anta Diop University, Avenue Cheikh Anta Diop, BP 5005 Fann, Dakar, Senegal
| | - Aida Sadikh Badiane
- Department of Parasitology and Mycology, Cheikh Anta Diop University, Avenue Cheikh Anta Diop, BP 5005 Fann, Dakar, Senegal
| | - Daouda Ndiaye
- Department of Parasitology and Mycology, Cheikh Anta Diop University, Avenue Cheikh Anta Diop, BP 5005 Fann, Dakar, Senegal
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The Plasmodium falciparum Artemisinin Susceptibility-Associated AP-2 Adaptin μ Subunit is Clathrin Independent and Essential for Schizont Maturation. mBio 2020; 11:mBio.02918-19. [PMID: 32098816 PMCID: PMC7042695 DOI: 10.1128/mbio.02918-19] [Citation(s) in RCA: 18] [Impact Index Per Article: 4.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/01/2023] Open
Abstract
The efficacy of current antimalarial drugs is threatened by reduced susceptibility of Plasmodium falciparum to artemisinin, associated with mutations in pfkelch13 Another gene with variants known to modulate the response to artemisinin encodes the μ subunit of the AP-2 adaptin trafficking complex. To elucidate the cellular role of AP-2μ in P. falciparum, we performed a conditional gene knockout, which severely disrupted schizont organization and maturation, leading to mislocalization of key merozoite proteins. AP-2μ is thus essential for blood-stage replication. We generated transgenic P. falciparum parasites expressing hemagglutinin-tagged AP-2μ and examined cellular localization by fluorescence and electron microscopy. Together with mass spectrometry analysis of coimmunoprecipitating proteins, these studies identified AP-2μ-interacting partners, including other AP-2 subunits, the K10 kelch-domain protein, and PfEHD, an effector of endocytosis and lipid mobilization, but no evidence was found of interaction with clathrin, the expected coat protein for AP-2 vesicles. In reverse immunoprecipitation experiments with a clathrin nanobody, other heterotetrameric AP-complexes were shown to interact with clathrin, but AP-2 complex subunits were absent.IMPORTANCE We examine in detail the AP-2 adaptin complex from the malaria parasite Plasmodium falciparum In most studied organisms, AP-2 is involved in bringing material into the cell from outside, a process called endocytosis. Previous work shows that changes to the μ subunit of AP-2 can contribute to drug resistance. Our experiments show that AP-2 is essential for parasite development in blood but does not have any role in clathrin-mediated endocytosis. This suggests that a specialized function for AP-2 has developed in malaria parasites, and this may be important for understanding its impact on drug resistance.
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Yang J, Li K, He D, Gu J, Xu J, Xie J, Zhang M, Liu Y, Tan Q, Zhang J. Toward a better understanding of metabolic and pharmacokinetic characteristics of low-solubility, low-permeability natural medicines. Drug Metab Rev 2020; 52:19-43. [PMID: 31984816 DOI: 10.1080/03602532.2020.1714646] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/07/2023]
Abstract
Today, it is very challenging to develop new active pharmaceutical ingredients. Developing good preparations of well-recognized natural medicines is certainly a practical and economic strategy. Low-solubility, low-permeability natural medicines (LLNMs) possess valuable advantages such as effectiveness, relative low cost and low toxicity, which is shown by the presence of popular products on the market. Understanding the in vivo metabolic and pharmacokinetic characteristics of LLNMs contributes to overcoming their associated problems, such as low absorption and low bioavailability. In this review, the structure-based metabolic reactions of LLNMs and related enzymatic systems, cellular and bodily pharmacological effects and metabolic influences, drug-drug interactions involved in metabolism and microenvironmental changes, and pharmacokinetics and dose-dependent/linear pharmacokinetic models are comprehensively evaluated. This review suggests that better pharmacological activity and pharmacokinetic behaviors may be achieved by modifying the metabolism through using nanotechnology and nanosystem in combination with the suitable administration route and dosage. It is noteworthy that novel nanosystems, such as triggered-release liposomes, nucleic acid polymer nanosystems and PEGylated dendrimers, in addition to prodrug and intestinal penetration enhancer, demonstrate encouraging performance. Insights into the metabolic and pharmacokinetic characteristics of LLNMs may help pharmacists to identify new LLNM formulations with high bioavailability and amazing efficacy and help physicians carry out LLNM-based precision medicine and individualized therapies.
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Affiliation(s)
- Jie Yang
- Chongqing Research Center for Pharmaceutical Engineering, Chongqing Medical University, Chongqing, China
| | - Kailing Li
- Chongqing Research Center for Pharmaceutical Engineering, Chongqing Medical University, Chongqing, China
| | - Dan He
- Chongqing Research Center for Pharmaceutical Engineering, Chongqing Medical University, Chongqing, China
| | - Jing Gu
- Department of Thoracic Surgery, Daping Hospital of Army Medical University, PLA, Chongqing, China
| | - Jingyu Xu
- Department of Biostatistics, Mailman School of Public Health, Columbia University, New York, NY, USA
| | - Jiaxi Xie
- Chongqing Research Center for Pharmaceutical Engineering, Chongqing Medical University, Chongqing, China
| | - Min Zhang
- Chongqing Research Center for Pharmaceutical Engineering, Chongqing Medical University, Chongqing, China
| | - Yuying Liu
- Chongqing Research Center for Pharmaceutical Engineering, Chongqing Medical University, Chongqing, China
| | - Qunyou Tan
- Department of Thoracic Surgery, Daping Hospital of Army Medical University, PLA, Chongqing, China
| | - Jingqing Zhang
- Chongqing Research Center for Pharmaceutical Engineering, Chongqing Medical University, Chongqing, China
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