1
|
Nair AS, Sekar M, Gan SH, Kumarasamy V, Subramaniyan V, Wu YS, Mat Rani NNI, Ravi S, Wong LS. Lawsone Unleashed: A Comprehensive Review on Chemistry, Biosynthesis, and Therapeutic Potentials. Drug Des Devel Ther 2024; 18:3295-3313. [PMID: 39081702 PMCID: PMC11288359 DOI: 10.2147/dddt.s463545] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/08/2024] [Accepted: 05/25/2024] [Indexed: 08/02/2024] Open
Abstract
Lawsone, a naturally occurring organic compound also called hennotannic acid, obtained mainly from Lawsonia inermis (Henna). It is a potential drug-like molecule with unique chemical and biological characteristics. Traditionally, henna is used in hair and skin coloring and is also a medicinal herb for various diseases. It is also widely used as a starting material for the synthesis of various drug molecules. In this review, we investigate on the chemistry, biosynthesis, physical and biological properties of lawsone. The results showed that lawsone has potential antioxidant, anti-inflammatory, antimicrobial and antitumor properties. It also induces cell cycle inhibition and programmed cell death in cancer, making it a potential chemotherapeutic agent. Additionally, inhibition of pro-inflammatory cytokine production makes it an essential treatment for inflammatory diseases. Exploration of its biosynthetic pathway can pave the way for its development into targets for new drug development. In future, well-thought-out clinical studies should be made to verify its safety and efficacy.
Collapse
Affiliation(s)
- Aathira Sujathan Nair
- School of Pharmacy, Monash University Malaysia, Bandar Sunway, Subang Jaya, Selangor, 47500, Malaysia
| | - Mahendran Sekar
- School of Pharmacy, Monash University Malaysia, Bandar Sunway, Subang Jaya, Selangor, 47500, Malaysia
| | - Siew Hua Gan
- School of Pharmacy, Monash University Malaysia, Bandar Sunway, Subang Jaya, Selangor, 47500, Malaysia
| | - Vinoth Kumarasamy
- Department of Parasitology & Medical Entomology, Faculty of Medicine, Universiti Kebangsaan Malaysia, Cheras, Kuala Lumpur, 56000, Malaysia
| | - Vetriselvan Subramaniyan
- Department of Medical Sciences, School of Medical and Life Sciences, Sunway University, Bandar Sunway, Selangor, 47500, Malaysia
| | - Yuan Seng Wu
- Sunway Microbiome Centre & Department of Biological Sciences, School of Medical and Life Sciences, Sunway University, Bandar Sunway, Selangor, 47500, Malaysia
| | - Nur Najihah Izzati Mat Rani
- Faculty of Pharmacy and Health Sciences, Royal College of Medicine Perak, Universiti Kuala Lumpur, Ipoh, Perak, 30450, Malaysia
| | - Subban Ravi
- Department of Chemistry, Karpagam Academy of Higher Education, Coimbatore, Tamil Nadu, India
| | - Ling Shing Wong
- Faculty of Health and Life Sciences, INTI International University, Nilai, 71800, Malaysia
| |
Collapse
|
2
|
Liu R, Li G, Li M, Wang B, Zhang D, Xu L, Zhao L, Liao R, Xu Q, Bei ZC, Song Y. In vitro interaction of naphthoquine with ivermectin, atovaquone, curcumin, and ketotifen in the asexual blood stage of Plasmodium falciparum 3D7. Microbiol Spectr 2024; 12:e0063024. [PMID: 38780257 PMCID: PMC11218538 DOI: 10.1128/spectrum.00630-24] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/25/2024] [Accepted: 04/22/2024] [Indexed: 05/25/2024] Open
Abstract
Naphthoquine is a promising candidate for antimalarial combination therapy. Its combination with artemisinin has demonstrated excellent efficacy in clinical trials conducted across various malaria-endemic areas. A co-formulated combination of naphthoquine and azithromycin has also shown high clinical efficacy for malaria prophylaxis in Southeast Asia. Developing new combination therapies using naphthoquine will provide additional arsenal responses to the growing threat of artemisinin resistance. Furthermore, due to its long half-life, the possible interaction of naphthoquine with other drugs also needs attention. However, studies on its pharmacodynamic interactions with other drugs are still limited. In this study, the in vitro interactions of naphthoquine with ivermectin, atovaquone, curcumin, and ketotifen were evaluated in the asexual stage of Plasmodium falciparum 3D7. By using the combination index analysis and the SYBR Green I-based fluorescence assay, different interaction patterns of selected drugs with naphthoquine were revealed. Curcumin showed a slight but significant synergistic interaction with naphthoquine at lower effect levels, and no antagonism was observed across the full range of effect levels for all tested ratios. Atovaquone showed a potency decline when combined with naphthoquine. For ivermectin, a significant antagonism with naphthoquine was observed at a broad range of effect levels below 75% inhibition, although no significant interaction was observed at higher effect levels. Ketotifen interacted with naphthoquine similar to ivermectin, but significant antagonism was observed for only one tested ratio. These findings should be helpful to the development of new naphthoquine-based combination therapy and the clinically reasonable application of naphthoquine-containing therapies. IMPORTANCE Pharmacodynamic interaction between antimalarials is not only crucial for the development of new antimalarial combination therapies but also important for the appropriate clinical use of antimalarials. The significant synergism between curcumin and naphthoquine observed in this study suggests the potential value for further development of new antimalarial combination therapy. The finding of a decline in atovaquone potency in the presence of naphthoquine alerts to a possible risk of treatment or prophylaxis failure for atovaquone-proguanil following naphthoquine-containing therapies. The observation of antagonism between naphthoquine and ivermectin raised a need for concern about the applicability of naphthoquine-containing therapy in malaria-endemic areas with ivermectin mass drug administration deployed. Considering the role of atovaquone-proguanil as a major alternative when first-line artemisinin-based combination therapy is ineffective and the wide implementation of ivermectin mass drug administration in malaria-endemic countries, the above findings will be important for the appropriate clinical application of antimalarials involving naphthoquine-containing therapies.
Collapse
Affiliation(s)
- Ruotong Liu
- Artemisinin Research Center, Guangzhou University of Chinese Medicine, Guangzhou, China
- State Key Laboratory of Pathogen and Biosecurity, Beijing Institute of Microbiology and Epidemiology, Beijing, China
| | - Guoming Li
- Artemisinin Research Center, Guangzhou University of Chinese Medicine, Guangzhou, China
- State Key Laboratory of Pathogen and Biosecurity, Beijing Institute of Microbiology and Epidemiology, Beijing, China
| | - Mei Li
- Artemisinin Research Center, Guangzhou University of Chinese Medicine, Guangzhou, China
- State Key Laboratory of Pathogen and Biosecurity, Beijing Institute of Microbiology and Epidemiology, Beijing, China
| | - Baogang Wang
- State Key Laboratory of Pathogen and Biosecurity, Beijing Institute of Microbiology and Epidemiology, Beijing, China
| | - Dongna Zhang
- State Key Laboratory of Pathogen and Biosecurity, Beijing Institute of Microbiology and Epidemiology, Beijing, China
| | - Likun Xu
- State Key Laboratory of Pathogen and Biosecurity, Beijing Institute of Microbiology and Epidemiology, Beijing, China
| | - Liangliang Zhao
- State Key Laboratory of Pathogen and Biosecurity, Beijing Institute of Microbiology and Epidemiology, Beijing, China
| | - Ruhe Liao
- Artemisinin Research Center, Guangzhou University of Chinese Medicine, Guangzhou, China
- State Key Laboratory of Pathogen and Biosecurity, Beijing Institute of Microbiology and Epidemiology, Beijing, China
| | - Qin Xu
- Artemisinin Research Center, Guangzhou University of Chinese Medicine, Guangzhou, China
| | - Zhu-Chun Bei
- State Key Laboratory of Pathogen and Biosecurity, Beijing Institute of Microbiology and Epidemiology, Beijing, China
| | - Yabin Song
- State Key Laboratory of Pathogen and Biosecurity, Beijing Institute of Microbiology and Epidemiology, Beijing, China
| |
Collapse
|
3
|
Mahanta PJ, Lhouvum K. Plasmodium falciparum proteases as new drug targets with special focus on metalloproteases. Mol Biochem Parasitol 2024; 258:111617. [PMID: 38554736 DOI: 10.1016/j.molbiopara.2024.111617] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/17/2023] [Revised: 02/15/2024] [Accepted: 03/10/2024] [Indexed: 04/02/2024]
Abstract
Malaria poses a significant global health threat particularly due to the prevalence of Plasmodium falciparum infection. With the emergence of parasite resistance to existing drugs including the recently discovered artemisinin, ongoing research seeks novel therapeutic avenues within the malaria parasite. Proteases are promising drug targets due to their essential roles in parasite biology, including hemoglobin digestion, merozoite invasion, and egress. While exploring the genomic landscape of Plasmodium falciparum, it has been revealed that there are 92 predicted proteases, with only approximately 14 of them having been characterized. These proteases are further distributed among 26 families grouped into five clans: aspartic proteases, cysteine proteases, metalloproteases, serine proteases, and threonine proteases. Focus on metalloprotease class shows further role in organelle processing for mitochondria and apicoplasts suggesting the potential of metalloproteases as viable drug targets. Holistic understanding of the parasite intricate life cycle and identification of potential drug targets are essential for developing effective therapeutic strategies against malaria and mitigating its devastating global impact.
Collapse
Affiliation(s)
| | - Kimjolly Lhouvum
- Department of Biotechnology, National Institute of Technology, Arunachal Pradesh, India.
| |
Collapse
|
4
|
Platon L, Ménard D. Plasmodium falciparum ring-stage plasticity and drug resistance. Trends Parasitol 2024; 40:118-130. [PMID: 38104024 DOI: 10.1016/j.pt.2023.11.007] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/26/2023] [Revised: 11/15/2023] [Accepted: 11/15/2023] [Indexed: 12/19/2023]
Abstract
Malaria is a life-threatening tropical disease caused by parasites of the genus Plasmodium, of which Plasmodium falciparum is the most lethal. Malaria parasites have a complex life cycle, with stages occurring in both the Anopheles mosquito vector and human host. Ring stages are the youngest form of the parasite in the intraerythrocytic developmental cycle and are associated with evasion of spleen clearance, temporary growth arrest (TGA), and drug resistance. This formidable ability to survive and develop into mature, sexual, or growth-arrested forms demonstrates the inherent population heterogeneity. Here we highlight the role of the ring stage as a crossroads in parasite development and as a reservoir of surviving cells in the human host via TGA survival mechanisms.
Collapse
Affiliation(s)
- Lucien Platon
- Institut Pasteur, Université Paris Cité, Malaria Genetics and Resistance Unit, INSERM U1201, F-75015 Paris, France; Sorbonne Université, Collège Doctoral ED 515 Complexité du Vivant, F-75015 Paris, France; Université de Strasbourg, Institute of Parasitology and Tropical Diseases, UR7292 Dynamics of Host-Pathogen Interactions, F-67000 Strasbourg, France.
| | - Didier Ménard
- Institut Pasteur, Université Paris Cité, Malaria Genetics and Resistance Unit, INSERM U1201, F-75015 Paris, France; Institut Pasteur, Université Paris Cité, Malaria Parasite Biology and Vaccines Unit, F-75015 Paris, France; Université de Strasbourg, Institute of Parasitology and Tropical Diseases, UR7292 Dynamics of Host-Pathogen Interactions, F-67000 Strasbourg, France; CHU Strasbourg, Laboratory of Parasitology and Medical Mycology, F-67000 Strasbourg, France.
| |
Collapse
|
5
|
Hao Z, Chen J, Sun P, Chen L, Zhang Y, Chen W, Hu D, Bi F, Han Z, Tang X, Suo J, Suo X, Liu X. Distinct non-synonymous mutations in cytochrome b highly correlate with decoquinate resistance in apicomplexan parasite Eimeria tenella. Parasit Vectors 2023; 16:365. [PMID: 37848977 PMCID: PMC10583425 DOI: 10.1186/s13071-023-05988-7] [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: 07/16/2023] [Accepted: 09/28/2023] [Indexed: 10/19/2023] Open
Abstract
BACKGROUND Protozoan parasites of the genus Eimeria are the causative agents of chicken coccidiosis. Parasite resistance to most anticoccidial drugs is one of the major challenges to controlling this disease. There is an urgent need for a molecular marker to monitor the emergence of resistance against anticoccidial drugs, such as decoquinate. METHODS We developed decoquinate-resistant strains by successively exposing the Houghton (H) and Xinjiang (XJ) strains of E. tenella to incremental concentrations of this drug in chickens. Additionally, we isolated a decoquinate-resistant strain from the field. The resistance of these three strains was tested using the criteria of weight gain, relative oocyst production and reduction of lesion scores. Whole-genome sequencing was used to identify the non-synonymous mutations in coding genes that were highly associated with the decoquinate-resistant phenotype in the two laboratory-induced strains. Subsequently, we scrutinized the missense mutation in a field-resistant strain for verification. We also employed the AlphaFold and PyMOL systems to model the alterations in the binding affinity of the mutants toward the drug molecule. RESULTS We obtained two decoquinate-resistant (DecR) strains, DecR_H and XJ, originating from the original H and XJ strains, respectively, as well as a decoquinate-resistant E. tenella strain from the field (DecR_SC). These three strains displayed resistance to 120 mg/kg decoquinate administered through feed. Through whole-genome sequencing analysis, we identified the cytochrome b gene (cyt b; ETH2_MIT00100) as the sole mutated gene shared between the DecR_H and XJ strains and also detected this gene in the DecR_SC strain. Distinct non-synonymous mutations, namely Gln131Lys in DecR_H, Phe263Leu in DecR_XJ, and Phe283Leu in DecR_SC were observed in the three resistant strains. Notably, these mutations were located in the extracellular segments of cyt b, in close proximity to the ubiquinol oxidation site Qo. Drug molecular docking studies revealed that cyt b harboring these mutants exhibited varying degrees of reduced binding ability to decoquinate. CONCLUSIONS Our findings emphasize the critical role of cyt b mutations in the development of decoquinate resistance in E. tenella. The strong correlation observed between cyt b mutant alleles and resistance indicates their potential as valuable molecular markers for the rapid detection of decoquinate resistance.
Collapse
Affiliation(s)
- Zhenkai Hao
- National Key Laboratory of Veterinary Public Health and Safety, Key Laboratory of Animal Epidemiology and Zoonosis of Ministry of Agriculture, National Animal Protozoa Laboratory & College of Veterinary Medicine, China Agricultural University, Beijing, 100193, China
| | - Junmin Chen
- National Key Laboratory of Veterinary Public Health and Safety, Key Laboratory of Animal Epidemiology and Zoonosis of Ministry of Agriculture, National Animal Protozoa Laboratory & College of Veterinary Medicine, China Agricultural University, Beijing, 100193, China
| | - Pei Sun
- National Key Laboratory of Veterinary Public Health and Safety, Key Laboratory of Animal Epidemiology and Zoonosis of Ministry of Agriculture, National Animal Protozoa Laboratory & College of Veterinary Medicine, China Agricultural University, Beijing, 100193, China
| | - Linlin Chen
- National Key Laboratory of Veterinary Public Health and Safety, Key Laboratory of Animal Epidemiology and Zoonosis of Ministry of Agriculture, National Animal Protozoa Laboratory & College of Veterinary Medicine, China Agricultural University, Beijing, 100193, China
| | - Yuanyuan Zhang
- Key Laboratory of Animal Genetics, Breeding and Reproduction of the Ministry of Agriculture & Beijing Key Laboratory of Animal Genetics Improvement, China Agricultural University, Beijing, China
| | - Wenxuan Chen
- National Key Laboratory of Veterinary Public Health and Safety, Key Laboratory of Animal Epidemiology and Zoonosis of Ministry of Agriculture, National Animal Protozoa Laboratory & College of Veterinary Medicine, China Agricultural University, Beijing, 100193, China
| | - Dandan Hu
- School of Animal Science and Technology, Guangxi University, Guangxi, China
| | - Feifei Bi
- National Key Laboratory of Veterinary Public Health and Safety, Key Laboratory of Animal Epidemiology and Zoonosis of Ministry of Agriculture, National Animal Protozoa Laboratory & College of Veterinary Medicine, China Agricultural University, Beijing, 100193, China
| | - Zhenyan Han
- National Key Laboratory of Veterinary Public Health and Safety, Key Laboratory of Animal Epidemiology and Zoonosis of Ministry of Agriculture, National Animal Protozoa Laboratory & College of Veterinary Medicine, China Agricultural University, Beijing, 100193, China
| | - Xinming Tang
- Key Laboratory of Animal Biosafety Risk Prevention and Control (North) of MARA, Institute of Animal Sciences, Chinese Academy of Agricultural Sciences, Beijing, China
| | - Jingxia Suo
- National Key Laboratory of Veterinary Public Health and Safety, Key Laboratory of Animal Epidemiology and Zoonosis of Ministry of Agriculture, National Animal Protozoa Laboratory & College of Veterinary Medicine, China Agricultural University, Beijing, 100193, China
| | - Xun Suo
- National Key Laboratory of Veterinary Public Health and Safety, Key Laboratory of Animal Epidemiology and Zoonosis of Ministry of Agriculture, National Animal Protozoa Laboratory & College of Veterinary Medicine, China Agricultural University, Beijing, 100193, China
| | - Xianyong Liu
- National Key Laboratory of Veterinary Public Health and Safety, Key Laboratory of Animal Epidemiology and Zoonosis of Ministry of Agriculture, National Animal Protozoa Laboratory & College of Veterinary Medicine, China Agricultural University, Beijing, 100193, China.
| |
Collapse
|
6
|
Neupane S, Khadka J, Rayamajhi S, Pandey AS. Binding modes of potential anti-prion phytochemicals to PrP C structures in silico. J Ayurveda Integr Med 2023; 14:100750. [PMID: 37453159 PMCID: PMC10368899 DOI: 10.1016/j.jaim.2023.100750] [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: 08/24/2020] [Revised: 03/13/2023] [Accepted: 06/14/2023] [Indexed: 07/18/2023] Open
Abstract
BACKGROUND Prion diseases involve the conversion of a normal, cell-surface glycoprotein (PrPC) into a misfolded pathogenic form (PrPSc). One possible strategy to inhibit PrPSc formation is to stabilize the native conformation of PrPC and interfere with the conversion of PrPC to PrPSc. Many compounds have been shown to inhibit the conversion process, however, no promising drugs have been identified to cure prion diseases. OBJECTIVE This study aims to identify potential anti-prion compounds from plant phytochemicals by integrating traditional ethnobotanical knowledge with modern in silico drug design approaches. MATERIALS AND METHODS In the current study medicinal phytochemicals were docked with swapped and non-swapped crystal structures of PrPCin silico to identify potential anti-prions to determine their binding modes and interactions. RESULTS Eleven new phytochemicals were identified based on their binding energies and pharmacokinetic properties. The binding sites and interactions of the known and new anti-prion compounds are similar, and differences in binding modes occur in structures with very subtle differences in side chain conformations. Binding of these compounds poses steric hindrance to neighbouring molecules. Residues shown to be associated with the inhibition of PrPC to PrPSc conversion form interactions with most of the compounds. CONCLUSION Identified compounds might act as potent inhibitors of PrPC to PrPSc conversion. These might be attractive candidates for the development of novel anti-prion therapy although further tests in vitro cell cultures and in vivo mouse models are needed to confirm these findings.
Collapse
Affiliation(s)
- Sandesh Neupane
- Purbanchal University, Department of Biotechnology, SANN International College, Kathmandu, 44616, Nepal.
| | - Jenisha Khadka
- Purbanchal University, Department of Biotechnology, SANN International College, Kathmandu, 44616, Nepal.
| | - Sandesh Rayamajhi
- Purbanchal University, Department of Biotechnology, SANN International College, Kathmandu, 44616, Nepal.
| | - Arti S Pandey
- Department of Biochemistry, Kathmandu Medical College (Basic Sciences), Bhaktapur, 44800, Nepal.
| |
Collapse
|
7
|
Hayward JA, Makota FV, Cihalova D, Leonard RA, Rajendran E, Zwahlen SM, Shuttleworth L, Wiedemann U, Spry C, Saliba KJ, Maier AG, van Dooren GG. A screen of drug-like molecules identifies chemically diverse electron transport chain inhibitors in apicomplexan parasites. PLoS Pathog 2023; 19:e1011517. [PMID: 37471441 PMCID: PMC10403144 DOI: 10.1371/journal.ppat.1011517] [Citation(s) in RCA: 2] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/18/2022] [Revised: 08/04/2023] [Accepted: 06/28/2023] [Indexed: 07/22/2023] Open
Abstract
Apicomplexans are widespread parasites of humans and other animals, and include the causative agents of malaria (Plasmodium species) and toxoplasmosis (Toxoplasma gondii). Existing anti-apicomplexan therapies are beset with issues around drug resistance and toxicity, and new treatment options are needed. The mitochondrial electron transport chain (ETC) is one of the few processes that has been validated as a drug target in apicomplexans. To identify new inhibitors of the apicomplexan ETC, we developed a Seahorse XFe96 flux analyzer approach to screen the 400 compounds contained within the Medicines for Malaria Venture 'Pathogen Box' for ETC inhibition. We identified six chemically diverse, on-target inhibitors of the ETC in T. gondii, at least four of which also target the ETC of Plasmodium falciparum. Two of the identified compounds (MMV024937 and MMV688853) represent novel ETC inhibitor chemotypes. MMV688853 belongs to a compound class, the aminopyrazole carboxamides, that were shown previously to target a kinase with a key role in parasite invasion of host cells. Our data therefore reveal that MMV688853 has dual targets in apicomplexans. We further developed our approach to pinpoint the molecular targets of these inhibitors, demonstrating that all target Complex III of the ETC, with MMV688853 targeting the ubiquinone reduction (Qi) site of the complex. Most of the compounds we identified remain effective inhibitors of parasites that are resistant to Complex III inhibitors that are in clinical use or development, indicating that they could be used in treating drug resistant parasites. In sum, we have developed a versatile, scalable approach to screen for compounds that target the ETC in apicomplexan parasites, and used this to identify and characterize novel inhibitors.
Collapse
Affiliation(s)
- Jenni A. Hayward
- Research School of Biology, Australian National University, Canberra, Australia
| | - F. Victor Makota
- Research School of Biology, Australian National University, Canberra, Australia
| | - Daniela Cihalova
- Research School of Biology, Australian National University, Canberra, Australia
| | - Rachel A. Leonard
- Research School of Biology, Australian National University, Canberra, Australia
| | - Esther Rajendran
- Research School of Biology, Australian National University, Canberra, Australia
| | - Soraya M. Zwahlen
- Research School of Biology, Australian National University, Canberra, Australia
| | - Laura Shuttleworth
- Research School of Biology, Australian National University, Canberra, Australia
| | - Ursula Wiedemann
- Research School of Biology, Australian National University, Canberra, Australia
| | - Christina Spry
- Research School of Biology, Australian National University, Canberra, Australia
| | - Kevin J. Saliba
- Research School of Biology, Australian National University, Canberra, Australia
| | - Alexander G. Maier
- Research School of Biology, Australian National University, Canberra, Australia
| | - Giel G. van Dooren
- Research School of Biology, Australian National University, Canberra, Australia
| |
Collapse
|
8
|
Holbrook NR, Klontz EH, Adams GC, Schnittman SR, Issa NC, Bond SA, Branda JA, Lemieux JE. Babesia microti Variant With Multiple Resistance Mutations Detected in an Immunocompromised Patient Receiving Atovaquone Prophylaxis. Open Forum Infect Dis 2023; 10:ofad097. [PMID: 36968958 PMCID: PMC10034591 DOI: 10.1093/ofid/ofad097] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/06/2022] [Accepted: 02/21/2023] [Indexed: 02/25/2023] Open
Abstract
We report Babesia microti genomic sequences with multiple mutations in the atovaquone-target region of cytochrome b, including a newly identified Y272S mutation, plus 1 mutation of undetermined significance in the azithromycin-associated ribosomal protein L4. The parasite was sequenced from an immunocompromised patient on prophylactic atovaquone for Pneumocystis pneumonia before diagnosis of babesiosis.
Collapse
Affiliation(s)
- Nolan R Holbrook
- Department of Pathology, Massachusetts General Hospital, Boston, Massachusetts, USA
- Infectious Diseases Division, Massachusetts General Hospital, Boston, Massachusetts, USA
| | - Erik H Klontz
- Department of Pathology, Massachusetts General Hospital, Boston, Massachusetts, USA
| | - Gordon C Adams
- Infectious Diseases Division, Massachusetts General Hospital, Boston, Massachusetts, USA
| | - Samuel R Schnittman
- Division of Infectious Diseases, Brigham and Women’s Hospital, Boston, Massachusetts, USA
| | - Nicolas C Issa
- Division of Infectious Diseases, Brigham and Women’s Hospital, Boston, Massachusetts, USA
| | - Sheila A Bond
- Division of Infectious Diseases, Brigham and Women’s Hospital, Boston, Massachusetts, USA
| | - John A Branda
- Department of Pathology, Massachusetts General Hospital, Boston, Massachusetts, USA
| | - Jacob E Lemieux
- Infectious Diseases Division, Massachusetts General Hospital, Boston, Massachusetts, USA
| |
Collapse
|
9
|
Jeffreys LN, Ardrey A, Hafiz TA, Dyer LA, Warman AJ, Mosallam N, Nixon GL, Fisher NE, Hong WD, Leung SC, Aljayyoussi G, Bibby J, Almeida DV, Converse PJ, Fotouhi N, Berry NG, Nuermberger EL, Upton AM, O'Neill PM, Ward SA, Biagini GA. Identification of 2-Aryl-Quinolone Inhibitors of Cytochrome bd and Chemical Validation of Combination Strategies for Respiratory Inhibitors against Mycobacterium tuberculosis. ACS Infect Dis 2023; 9:221-238. [PMID: 36606559 PMCID: PMC9926492 DOI: 10.1021/acsinfecdis.2c00283] [Citation(s) in RCA: 7] [Impact Index Per Article: 7.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/07/2023]
Abstract
Mycobacterium tuberculosis cytochrome bd quinol oxidase (cyt bd), the alternative terminal oxidase of the respiratory chain, has been identified as playing a key role during chronic infection and presents a putative target for the development of novel antitubercular agents. Here, we report confirmation of successful heterologous expression of M. tuberculosis cytochrome bd. The heterologous M. tuberculosis cytochrome bd expression system was used to identify a chemical series of inhibitors based on the 2-aryl-quinolone pharmacophore. Cytochrome bd inhibitors displayed modest efficacy in M. tuberculosis growth suppression assays together with a bacteriostatic phenotype in time-kill curve assays. Significantly, however, inhibitor combinations containing our front-runner cyt bd inhibitor CK-2-63 with either cyt bcc-aa3 inhibitors (e.g., Q203) and/or adenosine triphosphate (ATP) synthase inhibitors (e.g., bedaquiline) displayed enhanced efficacy with respect to the reduction of mycobacterium oxygen consumption, growth suppression, and in vitro sterilization kinetics. In vivo combinations of Q203 and CK-2-63 resulted in a modest lowering of lung burden compared to treatment with Q203 alone. The reduced efficacy in the in vivo experiments compared to in vitro experiments was shown to be a result of high plasma protein binding and a low unbound drug exposure at the target site. While further development is required to improve the tractability of cyt bd inhibitors for clinical evaluation, these data support the approach of using small-molecule inhibitors to target multiple components of the branched respiratory chain of M. tuberculosis as a combination strategy to improve therapeutic and pharmacokinetic/pharmacodynamic (PK/PD) indices related to efficacy.
Collapse
Affiliation(s)
- Laura N Jeffreys
- Centre for Drugs and Diagnostics, Department of Tropical Infectious Diseases, Liverpool School of Tropical Medicine, Pembroke Place, LiverpoolL3 5QA, U.K
| | - Alison Ardrey
- Centre for Drugs and Diagnostics, Department of Tropical Infectious Diseases, Liverpool School of Tropical Medicine, Pembroke Place, LiverpoolL3 5QA, U.K
| | - Taghreed A Hafiz
- Centre for Drugs and Diagnostics, Department of Tropical Infectious Diseases, Liverpool School of Tropical Medicine, Pembroke Place, LiverpoolL3 5QA, U.K
| | - Lauri-Anne Dyer
- Centre for Drugs and Diagnostics, Department of Tropical Infectious Diseases, Liverpool School of Tropical Medicine, Pembroke Place, LiverpoolL3 5QA, U.K
| | - Ashley J Warman
- Centre for Drugs and Diagnostics, Department of Tropical Infectious Diseases, Liverpool School of Tropical Medicine, Pembroke Place, LiverpoolL3 5QA, U.K
| | - Nada Mosallam
- Department of Chemistry, University of Liverpool, LiverpoolL69 7ZD, U.K
| | - Gemma L Nixon
- Department of Chemistry, University of Liverpool, LiverpoolL69 7ZD, U.K
| | - Nicholas E Fisher
- Centre for Drugs and Diagnostics, Department of Tropical Infectious Diseases, Liverpool School of Tropical Medicine, Pembroke Place, LiverpoolL3 5QA, U.K
| | - W David Hong
- Department of Chemistry, University of Liverpool, LiverpoolL69 7ZD, U.K
| | - Suet C Leung
- Department of Chemistry, University of Liverpool, LiverpoolL69 7ZD, U.K
| | - Ghaith Aljayyoussi
- Centre for Drugs and Diagnostics, Department of Tropical Infectious Diseases, Liverpool School of Tropical Medicine, Pembroke Place, LiverpoolL3 5QA, U.K
| | - Jaclyn Bibby
- Department of Chemistry, University of Liverpool, LiverpoolL69 7ZD, U.K
| | - Deepak V Almeida
- Center for Tuberculosis Research, Johns Hopkins University School of Medicine, Baltimore, Maryland21205, United States
| | - Paul J Converse
- Center for Tuberculosis Research, Johns Hopkins University School of Medicine, Baltimore, Maryland21205, United States
| | - Nader Fotouhi
- Global Alliance for TB Drug Development, New York, New York10005, United States
| | - Neil G Berry
- Department of Chemistry, University of Liverpool, LiverpoolL69 7ZD, U.K
| | - Eric L Nuermberger
- Center for Tuberculosis Research, Johns Hopkins University School of Medicine, Baltimore, Maryland21205, United States
| | - Anna M Upton
- Global Alliance for TB Drug Development, New York, New York10005, United States.,Evotec (US) Inc., 303B College Road East, Princeton, New Jersey08540, United States
| | - Paul M O'Neill
- Department of Chemistry, University of Liverpool, LiverpoolL69 7ZD, U.K
| | - Stephen A Ward
- Centre for Drugs and Diagnostics, Department of Tropical Infectious Diseases, Liverpool School of Tropical Medicine, Pembroke Place, LiverpoolL3 5QA, U.K
| | - Giancarlo A Biagini
- Centre for Drugs and Diagnostics, Department of Tropical Infectious Diseases, Liverpool School of Tropical Medicine, Pembroke Place, LiverpoolL3 5QA, U.K
| |
Collapse
|
10
|
Alday PH, Nilsen A, Doggett JS. Structure-activity relationships of Toxoplasma gondii cytochrome bc1 inhibitors. Expert Opin Drug Discov 2022; 17:997-1011. [PMID: 35772172 PMCID: PMC9561756 DOI: 10.1080/17460441.2022.2096588] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/18/2022] [Accepted: 06/28/2022] [Indexed: 11/04/2022]
Abstract
INTRODUCTION Toxoplasma gondii is a prolific apicomplexan parasite that infects human and nonhuman animals worldwide and can cause severe brain and eye disease. Safer, more effective therapies for toxoplasmosis are needed. Cytochrome bc1 inhibitors are remarkably effective against toxoplasmosis and other apicomplexan-caused diseases. AREAS COVERED This work reviews T. gondii cytochrome bc1 inhibitors. Emphasis is placed on the structure-activity relationships of these inhibitors with regard to efficacy, pharmacokinetics, selectivity of T. gondii cytochrome bc1 over host, safety, and potential therapeutic strategies. EXPERT OPINION Cytochrome bc1 inhibitors are highly promising compounds for toxoplasmosis that have been effective in clinical and preclinical studies. Clinical experience with atovaquone previously validated cytochrome bc1 as a tractable drug target and, over the past decade, optimization of cytochrome bc1 inhibitors has resulted in improved bioavailability, metabolic stability, potency, blood-brain barrier penetration, and selectivity for the T. gondii cytochrome bc1 over the mammalian bc1. Recent studies have demonstrated preclinical safety, identified novel therapeutic strategies for toxoplasmosis using synergistic combinations or long-acting administration and provided insight into their role in chronic infection. This research has identified drug candidates that are more effective than clinically used drugs in preclinical measures of efficacy.
Collapse
Affiliation(s)
- Phil Holland Alday
- Portland VA Medical Center, Portland, Oregon, USA
- Oregon Health & Science University, Portland, Oregon, USA
| | - Aaron Nilsen
- Portland VA Medical Center, Portland, Oregon, USA
- Oregon Health & Science University, Portland, Oregon, USA
| | | |
Collapse
|
11
|
Amporndanai K, Pinthong N, O’Neill PM, Hong WD, Amewu RK, Pidathala C, Berry NG, Leung SC, Ward SA, Biagini GA, Hasnain SS, Antonyuk SV. Targeting the Ubiquinol-Reduction (Q i) Site of the Mitochondrial Cytochrome bc1 Complex for the Development of Next Generation Quinolone Antimalarials. BIOLOGY 2022; 11:biology11081109. [PMID: 35892964 PMCID: PMC9330653 DOI: 10.3390/biology11081109] [Citation(s) in RCA: 6] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 05/18/2022] [Revised: 07/11/2022] [Accepted: 07/18/2022] [Indexed: 11/16/2022]
Abstract
Antimalarials targeting the ubiquinol-oxidation (Qo) site of the Plasmodium falciparum bc1 complex, such as atovaquone, have become less effective due to the rapid emergence of resistance linked to point mutations in the Qo site. Recent findings showed a series of 2-aryl quinolones mediate inhibitions of this complex by binding to the ubiquinone-reduction (Qi) site, which offers a potential advantage in circumventing drug resistance. Since it is essential to understand how 2-aryl quinolone lead compounds bind within the Qi site, here we describe the co-crystallization and structure elucidation of the bovine cytochrome bc1 complex with three different antimalarial 4(1H)-quinolone sub-types, including two 2-aryl quinolone derivatives and a 3-aryl quinolone analogue for comparison. Currently, no structural information is available for Plasmodial cytochrome bc1. Our crystallographic studies have enabled comparison of an in-silico homology docking model of P. falciparum with the mammalian's equivalent, enabling an examination of how binding compares for the 2- versus 3-aryl analogues. Based on crystallographic and computational modeling, key differences in human and P. falciparum Qi sites have been mapped that provide new insights that can be exploited for the development of next-generation antimalarials with greater selective inhibitory activity against the parasite bc1 with improved antimalarial properties.
Collapse
Affiliation(s)
- Kangsa Amporndanai
- Molecular Biophysics Group, Institute of Systems, Molecular and Integrative Biology, Faculty of Health and Life Sciences, University of Liverpool, Liverpool L69 7ZB, UK; (K.A.); (N.P.); (S.S.H.)
- Department of Biochemistry, Vanderbilt University School of Medicine, Nashville, TN 37232-0146, USA
| | - Nattapon Pinthong
- Molecular Biophysics Group, Institute of Systems, Molecular and Integrative Biology, Faculty of Health and Life Sciences, University of Liverpool, Liverpool L69 7ZB, UK; (K.A.); (N.P.); (S.S.H.)
- Department of Protozoology, Faculty of Tropical Medicine, Mahidol University, Bangkok 10400, Thailand
| | - Paul M. O’Neill
- Department of Chemistry, University of Liverpool, Liverpool L69 7ZD, UK; (W.D.H.); (R.K.A.); (C.P.); (N.G.B.); (S.C.L.)
- Correspondence: (P.M.O.); (S.V.A.); Tel.: +44-(0)-1517955145 (S.V.A.); +44-(0)-1517943552 (P.M.O.)
| | - W. David Hong
- Department of Chemistry, University of Liverpool, Liverpool L69 7ZD, UK; (W.D.H.); (R.K.A.); (C.P.); (N.G.B.); (S.C.L.)
| | - Richard K. Amewu
- Department of Chemistry, University of Liverpool, Liverpool L69 7ZD, UK; (W.D.H.); (R.K.A.); (C.P.); (N.G.B.); (S.C.L.)
- Department of Chemistry, School of Physical and Mathematical Sciences, University of Ghana, Accra P.O. Box LG 586, Ghana
| | - Chandrakala Pidathala
- Department of Chemistry, University of Liverpool, Liverpool L69 7ZD, UK; (W.D.H.); (R.K.A.); (C.P.); (N.G.B.); (S.C.L.)
- Composite Interceptive Med-Science Laboratories Pvt. Ltd., Bengaluru 60099, Karnataka, India
| | - Neil G. Berry
- Department of Chemistry, University of Liverpool, Liverpool L69 7ZD, UK; (W.D.H.); (R.K.A.); (C.P.); (N.G.B.); (S.C.L.)
| | - Suet C. Leung
- Department of Chemistry, University of Liverpool, Liverpool L69 7ZD, UK; (W.D.H.); (R.K.A.); (C.P.); (N.G.B.); (S.C.L.)
| | - Stephen A. Ward
- Centre for Drugs and Diagnostics, Tropical Disease Biology, Liverpool School of Tropical Medicine, Liverpool L3 5QA, UK; (S.A.W.); (G.A.B.)
| | - Giancarlo A. Biagini
- Centre for Drugs and Diagnostics, Tropical Disease Biology, Liverpool School of Tropical Medicine, Liverpool L3 5QA, UK; (S.A.W.); (G.A.B.)
| | - S. Samar Hasnain
- Molecular Biophysics Group, Institute of Systems, Molecular and Integrative Biology, Faculty of Health and Life Sciences, University of Liverpool, Liverpool L69 7ZB, UK; (K.A.); (N.P.); (S.S.H.)
| | - Svetlana V. Antonyuk
- Molecular Biophysics Group, Institute of Systems, Molecular and Integrative Biology, Faculty of Health and Life Sciences, University of Liverpool, Liverpool L69 7ZB, UK; (K.A.); (N.P.); (S.S.H.)
- Correspondence: (P.M.O.); (S.V.A.); Tel.: +44-(0)-1517955145 (S.V.A.); +44-(0)-1517943552 (P.M.O.)
| |
Collapse
|
12
|
Chiu JE, Renard I, George S, Pal AC, Alday PH, Narasimhan S, Riscoe MK, Doggett JS, Ben Mamoun C. Cytochrome b Drug Resistance Mutation Decreases Babesia Fitness in the Tick Stages But Not the Mammalian Erythrocytic Cycle. J Infect Dis 2021; 225:135-145. [PMID: 34139755 PMCID: PMC8730496 DOI: 10.1093/infdis/jiab321] [Citation(s) in RCA: 6] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/31/2021] [Accepted: 06/15/2021] [Indexed: 12/28/2022] Open
Abstract
Human babesiosis is an emerging tick-borne malaria-like illness caused by Babesia parasites following their development in erythrocytes. Here, we show that a mutation in the Babesia microti mitochondrial cytochrome b (Cytb) that confers resistance to the antibabesial drug ELQ-502 decreases parasite fitness in the arthropod vector. Interestingly, whereas the mutant allele does not affect B. microti fitness during the mammalian blood phase of the parasite life cycle and is genetically stable as parasite burden increases, ELQ-502-resistant mutant parasites developing in the tick vector are genetically unstable with a high rate of the wild-type allele emerging during the nymphal stage. Furthermore, we show that B. microti parasites with this mutation are transmitted from the tick to the host, raising the possibility that the frequency of Cytb resistance mutations may be decreased by passage through the tick vector, but could persist in the environment if present when ticks feed.
Collapse
Affiliation(s)
- Joy E Chiu
- Section of Infectious Diseases, Department of Internal Medicine, Yale University School of Medicine, New Haven, Connecticut, USA
| | - Isaline Renard
- Section of Infectious Diseases, Department of Internal Medicine, Yale University School of Medicine, New Haven, Connecticut, USA
| | - Santosh George
- Section of Infectious Diseases, Department of Internal Medicine, Yale University School of Medicine, New Haven, Connecticut, USA
| | - Anasuya C Pal
- Section of Infectious Diseases, Department of Internal Medicine, Yale University School of Medicine, New Haven, Connecticut, USA
| | | | - Sukanya Narasimhan
- Section of Infectious Diseases, Department of Internal Medicine, Yale University School of Medicine, New Haven, Connecticut, USA
| | | | | | - Choukri Ben Mamoun
- Section of Infectious Diseases, Department of Internal Medicine, Yale University School of Medicine, New Haven, Connecticut, USA
- Correspondence: Choukri Ben Mamoun, PhD, Yale School of Medicine, Departments of Medicine and Microbial Pathogenesis, Section of Infectious Diseases, 300 Cedar Street, New Haven, CT 06520 ()
| |
Collapse
|
13
|
Duffey M, Blasco B, Burrows JN, Wells TNC, Fidock DA, Leroy D. Assessing risks of Plasmodium falciparum resistance to select next-generation antimalarials. Trends Parasitol 2021; 37:709-721. [PMID: 34001441 DOI: 10.1016/j.pt.2021.04.006] [Citation(s) in RCA: 50] [Impact Index Per Article: 16.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/17/2021] [Revised: 04/01/2021] [Accepted: 04/08/2021] [Indexed: 02/07/2023]
Abstract
Strategies to counteract or prevent emerging drug resistance are crucial for the design of next-generation antimalarials. In the past, resistant parasites were generally identified following treatment failures in patients, and compounds would have to be abandoned late in development. An early understanding of how candidate therapeutics lose efficacy as parasites evolve resistance is important to facilitate drug design and improve resistance detection and monitoring up to the postregistration phase. We describe a new strategy to assess resistance to antimalarial compounds as early as possible in preclinical development by leveraging tools to define the Plasmodium falciparum resistome, predict potential resistance risks of clinical failure for candidate therapeutics, and inform decisions to guide antimalarial drug development.
Collapse
Affiliation(s)
| | - Benjamin Blasco
- Medicines for Malaria Venture, Geneva, Switzerland; Global Antibiotic Research and Development Partnership, Geneva, Switzerland
| | | | | | - David A Fidock
- Department of Microbiology and Immunology, Columbia University Irving Medical Center, New York, NY, USA; Division of Infectious Diseases, Department of Medicine, Columbia University Irving Medical Center, New York, NY, USA
| | - Didier Leroy
- Medicines for Malaria Venture, Geneva, Switzerland.
| |
Collapse
|
14
|
Jacobsen L, Husen P, Solov'yov IA. Inhibition Mechanism of Antimalarial Drugs Targeting the Cytochrome bc 1 Complex. J Chem Inf Model 2021; 61:1334-1345. [PMID: 33617262 DOI: 10.1021/acs.jcim.0c01148] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Abstract
Plasmodium falciparum (P. falciparum) is the main parasite known to cause malaria in humans. The antimalarial drug atovaquone is known to inhibit the Qo-site of the cytochrome bc1 complex of P. falciparum, which ultimately blocks ATP synthesis, leading to cell death. Through the years, mutations of the P. falciparum cytochrome bc1 complex, causing resistance to atovaquone, have emerged. The present investigation applies molecular dynamics (MD) simulations to study how the specific mutations Y279S and L282V, known to cause atovaquone resistance in malarial parasites, affect the inhibition mechanism of two known inhibitors. Binding free energy estimates were obtained through free energy perturbation calculations but were unable to confidently resolve the effects of mutations due to the great complexity of the binding environment. Meanwhile, basic mechanistic considerations from the MD simulations provide a detailed characterization of inhibitor binding modes and indicate that the Y279S mutation weakens the natural binding of the inhibitors, while no conclusive effect of the L282V mutation could be observed.
Collapse
Affiliation(s)
- Luise Jacobsen
- Department of Physics, Chemistry and Pharmacy, University of Southern Denmark, Campusvej 55, 5230 Odense M, Denmark
| | - Peter Husen
- Department of Physics, Chemistry and Pharmacy, University of Southern Denmark, Campusvej 55, 5230 Odense M, Denmark
| | - Ilia A Solov'yov
- Department of Physics, Carl von Ossietzky University, Carl-von-Ossietzky-Strasse 9-11, 26129 Oldenburg, Germany
| |
Collapse
|
15
|
Chebon-Bore L, Sanyanga TA, Manyumwa CV, Khairallah A, Tastan Bishop Ö. Decoding the Molecular Effects of Atovaquone Linked Resistant Mutations on Plasmodium falciparum Cytb-ISP Complex in the Phospholipid Bilayer Membrane. Int J Mol Sci 2021; 22:2138. [PMID: 33670016 PMCID: PMC7926518 DOI: 10.3390/ijms22042138] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/30/2020] [Revised: 02/02/2021] [Accepted: 02/07/2021] [Indexed: 12/19/2022] Open
Abstract
Atovaquone (ATQ) is a drug used to prevent and treat malaria that functions by targeting the Plasmodium falciparum cytochrome b (PfCytb) protein. PfCytb catalyzes the transmembrane electron transfer (ET) pathway which maintains the mitochondrial membrane potential. The ubiquinol substrate binding site of the protein has heme bL, heme bH and iron-sulphur [2FE-2S] cluster cofactors that act as redox centers to aid in ET. Recent studies investigating ATQ resistance mechanisms have shown that point mutations of PfCytb confer resistance. Thus, understanding the resistance mechanisms at the molecular level via computational approaches incorporating phospholipid bilayer would help in the design of new efficacious drugs that are also capable of bypassing parasite resistance. With this knowledge gap, this article seeks to explore the effect of three drug resistant mutations Y268C, Y268N and Y268S on the PfCytb structure and function in the presence and absence of ATQ. To draw reliable conclusions, 350 ns all-atom membrane (POPC:POPE phospholipid bilayer) molecular dynamics (MD) simulations with derived metal parameters for the holo and ATQ-bound -proteins were performed. Thereafter, simulation outputs were analyzed using dynamic residue network (DRN) analysis. Across the triplicate MD runs, hydrophobic interactions, reported to be crucial in protein function were assessed. In both, the presence and absence of ATQ and a loss of key active site residue interactions were observed as a result of mutations. These active site residues included: Met 133, Trp136, Val140, Thr142, Ile258, Val259, Pro260 and Phe264. These changes to residue interactions are likely to destabilize the overall intra-protein residue communication network where the proteins' function could be implicated. Protein dynamics of the ATQ-bound mutant complexes showed that they assumed a different pose to the wild-type, resulting in diminished residue interactions in the mutant proteins. In summary, this study presents insights on the possible effect of the mutations on ATQ drug activity causing resistance and describes accurate MD simulations in the presence of the lipid bilayer prior to conducting inhibitory drug discovery for the PfCytb-iron sulphur protein (Cytb-ISP) complex.
Collapse
Affiliation(s)
| | | | | | | | - Özlem Tastan Bishop
- Research Unit in Bioinformatics (RUBi), Department of Biochemistry and Microbiology, Rhodes University, Makhanda 6140, South Africa; (L.C.-B.); (T.A.S.); (C.V.M.); (A.K.)
| |
Collapse
|
16
|
Patel OPS, Beteck RM, Legoabe LJ. Antimalarial application of quinones: A recent update. Eur J Med Chem 2020; 210:113084. [PMID: 33333397 DOI: 10.1016/j.ejmech.2020.113084] [Citation(s) in RCA: 42] [Impact Index Per Article: 10.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/19/2020] [Revised: 11/27/2020] [Accepted: 12/01/2020] [Indexed: 12/28/2022]
Abstract
Atovaquone belongs to a naphthoquinone class of drugs and is used in combination with proguanil (Malarone) for the treatment of acute, uncomplicated malaria caused by Plasmodium falciparum (including chloroquine-resistant P. falciparum/P. vivax). Numerous quinone-derived compounds have attracted considerable attention in the last few decades due to their potential in antimalarial drug discovery. Several semi-synthetic derivatives of natural quinones, synthetic quinones (naphtho-/benzo-quinone, anthraquinones, thiazinoquinones), and quinone-based hybrids were explored for their in vitro and in vivo antimalarial activities. A careful literature survey revealed that this topic has not been compiled as a review article so far. Therefore, we herein summarise the recent discovery (the year 2009-2020) of quinone based antimalarial compounds in chronological order. This compilation would be very useful towards the exploration of novel quinone-derived compounds against malarial parasites with promising efficacy and lesser side effects.
Collapse
Affiliation(s)
- Om P S Patel
- Centre of Excellence for Pharmaceutical Sciences, North-West University, Private Bag X6001, Potchefstroom, 2520, South Africa.
| | - Richard M Beteck
- Centre of Excellence for Pharmaceutical Sciences, North-West University, Private Bag X6001, Potchefstroom, 2520, South Africa
| | - Lesetja J Legoabe
- Centre of Excellence for Pharmaceutical Sciences, North-West University, Private Bag X6001, Potchefstroom, 2520, South Africa.
| |
Collapse
|
17
|
Fisher N, Meunier B, Biagini GA. The cytochrome bc 1 complex as an antipathogenic target. FEBS Lett 2020; 594:2935-2952. [PMID: 32573760 DOI: 10.1002/1873-3468.13868] [Citation(s) in RCA: 28] [Impact Index Per Article: 7.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/10/2020] [Revised: 05/31/2020] [Accepted: 06/10/2020] [Indexed: 12/15/2022]
Abstract
The cytochrome bc1 complex is a key component of the mitochondrial respiratory chains of many eukaryotic microorganisms that are pathogenic for plants or humans, such as fungi responsible for crop diseases and Plasmodium falciparum, which causes human malaria. Cytochrome bc1 is an enzyme that contains two (ubi)quinone/quinol-binding sites, which can be exploited for the development of fungicidal and chemotherapeutic agents. Here, we review recent progress in determination of the structure and mechanism of action of cytochrome bc1 , and the associated development of antimicrobial agents (and associated resistance mechanisms) targeting its activity.
Collapse
Affiliation(s)
- Nicholas Fisher
- MSU-DOE Plant Research Laboratory, Michigan State University, East Lansing, MI, USA
| | - Brigitte Meunier
- CEA, CNRS, Institute for Integrative Biology of the Cell (I2BC), Université Paris-Saclay, Gif-sur-Yvette, France
| | - Giancarlo A Biagini
- Parasitology Department, Research Centre for Drugs & Diagnostics, Liverpool School of Tropical Medicine, Liverpool, UK
| |
Collapse
|
18
|
von Seidlein L, Peto TJ, Tripura R, Pell C, Yeung S, Kindermans JM, Dondorp A, Maude R. Novel Approaches to Control Malaria in Forested Areas of Southeast Asia. Trends Parasitol 2019; 35:388-398. [PMID: 31076353 DOI: 10.1016/j.pt.2019.03.011] [Citation(s) in RCA: 27] [Impact Index Per Article: 5.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/30/2019] [Revised: 03/24/2019] [Accepted: 03/27/2019] [Indexed: 12/27/2022]
Abstract
The emergence and spread of drug resistance in the Greater Mekong Subregion (GMS) have added urgency to accelerate malaria elimination while reducing the treatment options. The remaining foci of malaria transmission are often in forests, where vectors tend to bite during daytime and outdoors, thus reducing the effectiveness of insecticide-treated bed nets. Limited periods of exposure suggest that chemoprophylaxis could be a promising strategy to protect forest workers against malaria. Here we discuss three major questions in optimizing malaria chemoprophylaxis for forest workers: which antimalarial drug regimens are most appropriate, how frequently the chemoprophylaxis should be delivered, and how to motivate forest workers to use, and adhere to, malaria prophylaxis.
Collapse
Affiliation(s)
- Lorenz von Seidlein
- Mahidol Oxford Tropical Medicine Research Unit, Faculty of Tropical Medicine, Mahidol University, Bangkok, Thailand; Centre for Tropical Medicine and Global Health, Nuffield Department of Medicine, University of Oxford, Oxford, UK.
| | - Thomas J Peto
- Mahidol Oxford Tropical Medicine Research Unit, Faculty of Tropical Medicine, Mahidol University, Bangkok, Thailand; Centre for Tropical Medicine and Global Health, Nuffield Department of Medicine, University of Oxford, Oxford, UK
| | - Rupam Tripura
- Mahidol Oxford Tropical Medicine Research Unit, Faculty of Tropical Medicine, Mahidol University, Bangkok, Thailand; Centre for Tropical Medicine and Global Health, Nuffield Department of Medicine, University of Oxford, Oxford, UK
| | - Christopher Pell
- Centre for Social Sciences and Global Health, University of Amsterdam, Amsterdam, The Netherlands; Amsterdam Institute for Global Health and Development, Amsterdam, The Netherlands
| | - Shunmay Yeung
- London School of Hygiene and Tropical Medicine, London, UK
| | | | - Arjen Dondorp
- Mahidol Oxford Tropical Medicine Research Unit, Faculty of Tropical Medicine, Mahidol University, Bangkok, Thailand; Centre for Tropical Medicine and Global Health, Nuffield Department of Medicine, University of Oxford, Oxford, UK
| | - Richard Maude
- Mahidol Oxford Tropical Medicine Research Unit, Faculty of Tropical Medicine, Mahidol University, Bangkok, Thailand; Centre for Tropical Medicine and Global Health, Nuffield Department of Medicine, University of Oxford, Oxford, UK; Harvard T.H. Chan School of Public Health, Harvard University, Boston, MA, USA
| |
Collapse
|
19
|
Ke H, Ganesan SM, Dass S, Morrisey JM, Pou S, Nilsen A, Riscoe MK, Mather MW, Vaidya AB. Mitochondrial type II NADH dehydrogenase of Plasmodium falciparum (PfNDH2) is dispensable in the asexual blood stages. PLoS One 2019; 14:e0214023. [PMID: 30964863 PMCID: PMC6456166 DOI: 10.1371/journal.pone.0214023] [Citation(s) in RCA: 22] [Impact Index Per Article: 4.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/22/2018] [Accepted: 03/05/2019] [Indexed: 11/23/2022] Open
Abstract
The battle against malaria has been substantially impeded by the recurrence of drug resistance in Plasmodium falciparum, the deadliest human malaria parasite. To counter the problem, novel antimalarial drugs are urgently needed, especially those that target unique pathways of the parasite, since they are less likely to have side effects. The mitochondrial type II NADH dehydrogenase (NDH2) of P. falciparum, PfNDH2 (PF3D7_0915000), has been considered a good prospective antimalarial drug target for over a decade, since malaria parasites lack the conventional multi-subunit NADH dehydrogenase, or Complex I, present in the mammalian mitochondrial electron transport chain (mtETC). Instead, Plasmodium parasites contain a single subunit NDH2, which lacks proton pumping activity and is absent in humans. A significant amount of effort has been expended to develop PfNDH2 specific inhibitors, yet the essentiality of PfNDH2 has not been convincingly verified. Herein, we knocked out PfNDH2 in P. falciparum via a CRISPR/Cas9 mediated approach. Deletion of PfNDH2 does not alter the parasite’s susceptibility to multiple mtETC inhibitors, including atovaquone and ELQ-300. We also show that the antimalarial activity of the fungal NDH2 inhibitor HDQ and its new derivative CK-2-68 is due to inhibition of the parasite cytochrome bc1 complex rather than PfNDH2. These compounds directly inhibit the ubiquinol-cytochrome c reductase activity of the malarial bc1 complex. Our results suggest that PfNDH2 is not likely a good antimalarial drug target.
Collapse
Affiliation(s)
- Hangjun Ke
- Center for Molecular Parasitology, Department of Microbiology and Immunology, Drexel University College of Medicine, Philadelphia, Pennsylvania, United States of America
- * E-mail:
| | - Suresh M. Ganesan
- Center for Molecular Parasitology, Department of Microbiology and Immunology, Drexel University College of Medicine, Philadelphia, Pennsylvania, United States of America
| | - Swati Dass
- Center for Molecular Parasitology, Department of Microbiology and Immunology, Drexel University College of Medicine, Philadelphia, Pennsylvania, United States of America
| | - Joanne M. Morrisey
- Center for Molecular Parasitology, Department of Microbiology and Immunology, Drexel University College of Medicine, Philadelphia, Pennsylvania, United States of America
| | - Sovitj Pou
- Portland VA Medical Center, Portland, Oregon, United States of America
| | - Aaron Nilsen
- Portland VA Medical Center, Portland, Oregon, United States of America
| | - Michael K. Riscoe
- Portland VA Medical Center, Portland, Oregon, United States of America
| | - Michael W. Mather
- Center for Molecular Parasitology, Department of Microbiology and Immunology, Drexel University College of Medicine, Philadelphia, Pennsylvania, United States of America
| | - Akhil B. Vaidya
- Center for Molecular Parasitology, Department of Microbiology and Immunology, Drexel University College of Medicine, Philadelphia, Pennsylvania, United States of America
| |
Collapse
|
20
|
David Hong W, Leung SC, Amporndanai K, Davies J, Priestley RS, Nixon GL, Berry NG, Samar Hasnain S, Antonyuk S, Ward SA, Biagini GA, O’Neill PM. Potent Antimalarial 2-Pyrazolyl Quinolone bc 1 (Q i) Inhibitors with Improved Drug-like Properties. ACS Med Chem Lett 2018; 9:1205-1210. [PMID: 30613327 DOI: 10.1021/acsmedchemlett.8b00371] [Citation(s) in RCA: 21] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/14/2018] [Accepted: 10/19/2018] [Indexed: 01/29/2023] Open
Abstract
A series of 2-pyrazolyl quinolones has been designed and synthesized in 5-7 steps to optimize for both in vitro antimalarial potency and various in vitro drug metabolism and pharmacokinetics (DMPK) features. The most potent compounds display no cross-resistance with multidrug resistant parasite strains (W2) compared to drug sensitive strains (3D7), with IC50 (concentration of drug required to achieve half maximal growth suppression) values in the range of 15-33 nM. Furthermore, members of the series retain moderate activity against the atovaquone-resistant parasite isolate (TM90C2B). The described 2-pyrazoyl series displays improved DMPK properties, including improved aqueous solubility compared to previously reported quinolone series and acceptable safety margin through in vitro cytotoxicity assessment. The 2-pyrazolyl quinolones are believed to bind to the ubiquinone-reducing Qi site of the parasite bc 1 complex, which is supported by crystallographic studies of bovine cytochrome bc 1 complex.
Collapse
Affiliation(s)
- W. David Hong
- Department of Chemistry, University of Liverpool, Liverpool, L69 7ZD, U.K
| | - Suet C. Leung
- Research Centre for Drugs & Diagnostics, Parasitology Department, Liverpool School of Tropical Medicine, Liverpool, L3 5QA, U.K
| | - Kangsa Amporndanai
- Molecular Biophysics Group, Institute of Integrative Biology, University of Liverpool, Liverpool, L69 7ZB, U.K
| | - Jill Davies
- Research Centre for Drugs & Diagnostics, Parasitology Department, Liverpool School of Tropical Medicine, Liverpool, L3 5QA, U.K
| | - Richard S. Priestley
- Research Centre for Drugs & Diagnostics, Parasitology Department, Liverpool School of Tropical Medicine, Liverpool, L3 5QA, U.K
| | - Gemma L. Nixon
- Department of Chemistry, University of Liverpool, Liverpool, L69 7ZD, U.K
| | - Neil G. Berry
- Department of Chemistry, University of Liverpool, Liverpool, L69 7ZD, U.K
| | - S. Samar Hasnain
- Molecular Biophysics Group, Institute of Integrative Biology, University of Liverpool, Liverpool, L69 7ZB, U.K
| | - Svetlana Antonyuk
- Molecular Biophysics Group, Institute of Integrative Biology, University of Liverpool, Liverpool, L69 7ZB, U.K
| | - Stephen A. Ward
- Research Centre for Drugs & Diagnostics, Parasitology Department, Liverpool School of Tropical Medicine, Liverpool, L3 5QA, U.K
| | - Giancarlo A. Biagini
- Research Centre for Drugs & Diagnostics, Parasitology Department, Liverpool School of Tropical Medicine, Liverpool, L3 5QA, U.K
| | - Paul M. O’Neill
- Department of Chemistry, University of Liverpool, Liverpool, L69 7ZD, U.K
| |
Collapse
|
21
|
Selection of Plasmodium falciparum cytochrome B mutants by putative PfNDH2 inhibitors. Proc Natl Acad Sci U S A 2018; 115:6285-6290. [PMID: 29844160 DOI: 10.1073/pnas.1804492115] [Citation(s) in RCA: 22] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/18/2022] Open
Abstract
Malaria control is threatened by a limited pipeline of effective pharmaceuticals against drug-resistant strains of Plasmodium falciparum Components of the mitochondrial electron transport chain (ETC) are attractive targets for drug development, owing to exploitable differences between the parasite and human ETC. Disruption of ETC function interferes with metabolic processes including de novo pyrimidine synthesis, essential for nucleic acid replication. We investigated the effects of ETC inhibitor selection on two distinct P. falciparum clones, Dd2 and 106/1. Compounds CK-2-68 and RYL-552, substituted quinolones reported to block P. falciparum NADH dehydrogenase 2 (PfNDH2; a type II NADH:quinone oxidoreductase), unexpectedly selected mutations at the quinol oxidation (Qo) pocket of P. falciparum cytochrome B (PfCytB). Selection experiments with atovaquone (ATQ) on 106/1 parasites yielded highly resistant PfCytB Y268S mutants seen in clinical infections that fail ATQ-proguanil treatment. In contrast, ATQ pressure on Dd2 yielded moderately resistant parasites carrying a PfCytB M133I or K272R mutation. Strikingly, all ATQ-selected mutants demonstrated little change or slight increase of sensitivity to CK-2-68 or RYL-552. Molecular docking studies demonstrated binding of all three ETC inhibitors to the Qo pocket of PfCytB, where Y268 forms strong van der Waals interactions with the hydroxynaphthoquinone ring of ATQ but not the quinolone ring of CK-2-68 or RYL-552. Our results suggest that combinations of suitable ETC inhibitors may be able to subvert or delay the development of P. falciparum drug resistance.
Collapse
|
22
|
Song Z, Iorga BI, Mounkoro P, Fisher N, Meunier B. The antimalarial compound
ELQ
‐400 is an unusual inhibitor of the
bc
1
complex, targeting both
Q
o
and
Q
i
sites. FEBS Lett 2018; 592:1346-1356. [DOI: 10.1002/1873-3468.13035] [Citation(s) in RCA: 25] [Impact Index Per Article: 4.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/20/2018] [Revised: 03/07/2018] [Accepted: 03/08/2018] [Indexed: 11/08/2022]
Affiliation(s)
- Zehua Song
- Translational Research Institute Henan Provincial People's Hospital School of Medicine Henan University Zhengzhou China
- Institute for Integrative Biology of the Cell (I2BC) CEA CNRS Université Paris‐Sud Université Paris‐Saclay Gif‐sur‐Yvette France
| | - Bogdan I. Iorga
- Institut de Chimie des Substances Naturelles CNRS UPR 2301 Labex LERMIT Université Paris‐Saclay Gif‐sur‐Yvette France
| | - Pierre Mounkoro
- Institute for Integrative Biology of the Cell (I2BC) CEA CNRS Université Paris‐Sud Université Paris‐Saclay Gif‐sur‐Yvette France
| | - Nicholas Fisher
- MSU‐DOE Plant Research Laboratory Michigan State University East Lansing MI USA
| | - Brigitte Meunier
- Institute for Integrative Biology of the Cell (I2BC) CEA CNRS Université Paris‐Sud Université Paris‐Saclay Gif‐sur‐Yvette France
| |
Collapse
|
23
|
Synthesis, SAR, and Docking Studies Disclose 2-Arylfuran-1,4-naphthoquinones as In Vitro Antiplasmodial Hits. J Trop Med 2017; 2017:7496934. [PMID: 29225629 PMCID: PMC5684547 DOI: 10.1155/2017/7496934] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/16/2017] [Revised: 08/11/2017] [Accepted: 08/27/2017] [Indexed: 12/13/2022] Open
Abstract
A total of 28 lapachol-related naphthoquinones with four different scaffolds were synthesized and spectroscopically characterized. In vitro antiplasmodial activity was assayed against the chloroquine-resistant Plasmodium falciparum W2 strain by the parasite lactate dehydrogenase (pLDH) method. Cytotoxicity against Hep G2A16 cell was determined by the MTT assay. All compounds disclosed higher in vitro antiplasmodial activity than lapachol. Ortho- and para-naphthoquinones with a furan ring fused to the quinonoid moiety were more potent than 2-hydroxy-3-(1′-alkenyl)-1,4-naphthoquinones, while ortho-furanonaphthoquinones were more cytotoxic. Molecular docking to Plasmodium targets Pfcyt bc1 complex and PfDHOD enzyme showed that five out of the 28 naphthoquinones disclosed favorable binding energies. Furanonaphthoquinones endowed with an aryl moiety linked to the furan ring are highlighted as new in vitro antiplasmodial lead compounds and warrant further investigation.
Collapse
|
24
|
+Targeting Mitochondrial Functions as Antimalarial Regime, What Is Next? CURRENT CLINICAL MICROBIOLOGY REPORTS 2017. [DOI: 10.1007/s40588-017-0075-5] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/18/2022]
|
25
|
Blasco B, Leroy D, Fidock DA. Antimalarial drug resistance: linking Plasmodium falciparum parasite biology to the clinic. Nat Med 2017; 23:917-928. [PMID: 28777791 DOI: 10.1038/nm.4381] [Citation(s) in RCA: 325] [Impact Index Per Article: 46.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/29/2017] [Accepted: 06/30/2017] [Indexed: 02/08/2023]
Abstract
The global adoption of artemisinin-based combination therapies (ACTs) in the early 2000s heralded a new era in effectively treating drug-resistant Plasmodium falciparum malaria. However, several Southeast Asian countries have now reported the emergence of parasites that have decreased susceptibility to artemisinin (ART) derivatives and ACT partner drugs, resulting in increasing rates of treatment failures. Here we review recent advances in understanding how antimalarials act and how resistance develops, and discuss new strategies for effectively combatting resistance, optimizing treatment and advancing the global campaign to eliminate malaria.
Collapse
Affiliation(s)
| | - Didier Leroy
- Medicines for Malaria Venture, Geneva, Switzerland
| | - David A Fidock
- Department of Microbiology and Immunology, Columbia University Medical Center, New York, New York, USA.,Division of Infectious Diseases, Department of Medicine, Columbia University Medical Center, New York, New York, USA
| |
Collapse
|
26
|
Is the Mitochondrion a Good Malaria Drug Target? Trends Parasitol 2017; 33:185-193. [DOI: 10.1016/j.pt.2016.10.002] [Citation(s) in RCA: 43] [Impact Index Per Article: 6.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/21/2016] [Revised: 09/25/2016] [Accepted: 10/06/2016] [Indexed: 01/21/2023]
|
27
|
Mohring F, Rahbari M, Zechmann B, Rahlfs S, Przyborski JM, Meyer AJ, Becker K. Determination of glutathione redox potential and pH value in subcellular compartments of malaria parasites. Free Radic Biol Med 2017; 104:104-117. [PMID: 28062360 DOI: 10.1016/j.freeradbiomed.2017.01.001] [Citation(s) in RCA: 17] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 08/03/2016] [Revised: 12/16/2016] [Accepted: 01/02/2017] [Indexed: 12/26/2022]
Abstract
The malaria parasite Plasmodium falciparum is exposed to multiple sources of oxidative challenge during its complex life cycle in the Anopheles vector and its human host. In order to further elucidate redox-based parasite host cell interactions and mechanisms of drug action, we targeted the genetically encoded glutathione redox sensor roGFP2 coupled to human glutaredoxin 1 (roGFP2-hGrx1) as well as the ratiometric pH sensor pHluorin to the apicoplast and the mitochondrion of P. falciparum. Using live cell imaging, this allowed for the first time the determination of the pH values of the apicoplast (7.12±0.40) and mitochondrion (7.37±0.09) in the intraerythrocytic asexual stages of the parasite. Based on the roGFP2-hGrx1 signals, glutathione-dependent redox potentials of -267mV and -328mV, respectively, were obtained. Employing these novel tools, initial studies on the effects of redox-active agents and clinically employed antimalarial drugs were carried out on both organelles.
Collapse
Affiliation(s)
- Franziska Mohring
- Biochemistry and Molecular Biology, Interdisciplinary Research Center, Justus Liebig University Giessen, Heinrich-Buff-Ring 26-32, 35392 Giessen, Germany
| | - Mahsa Rahbari
- Biochemistry and Molecular Biology, Interdisciplinary Research Center, Justus Liebig University Giessen, Heinrich-Buff-Ring 26-32, 35392 Giessen, Germany
| | - Bernd Zechmann
- Center for Microscopy and Imaging, Baylor University, 101 Bagby Ave., Waco, TX 76706, USA
| | - Stefan Rahlfs
- Biochemistry and Molecular Biology, Interdisciplinary Research Center, Justus Liebig University Giessen, Heinrich-Buff-Ring 26-32, 35392 Giessen, Germany
| | - Jude M Przyborski
- Parasitology, Philipps University Marburg, Karl-von-Frisch Strasse 8, 35043 Marburg, Germany
| | - Andreas J Meyer
- INRES-Chemical Signalling, University of Bonn, Friedrich-Ebert-Allee 144, 53113 Bonn, Germany
| | - Katja Becker
- Biochemistry and Molecular Biology, Interdisciplinary Research Center, Justus Liebig University Giessen, Heinrich-Buff-Ring 26-32, 35392 Giessen, Germany.
| |
Collapse
|
28
|
Sakata-Kato T, Wirth DF. A Novel Methodology for Bioenergetic Analysis of Plasmodium falciparum Reveals a Glucose-Regulated Metabolic Shift and Enables Mode of Action Analyses of Mitochondrial Inhibitors. ACS Infect Dis 2016; 2:903-916. [PMID: 27718558 DOI: 10.1021/acsinfecdis.6b00101] [Citation(s) in RCA: 18] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/24/2022]
Abstract
Given that resistance to all drugs in clinical use has arisen, discovery of new antimalarial drug targets is eagerly anticipated. The Plasmodium mitochondrion has been considered a promising drug target largely based on its significant divergence from the host organelle as well as its involvement in ATP production and pyrimidine biosynthesis. However, the functions of Plasmodium mitochondrial protein complexes and associated metabolic pathways are not fully characterized. Here, we report the development of novel and robust bioenergetic assay protocols for Plasmodium falciparum asexual parasites utilizing a Seahorse Bioscience XFe24 Extracellular Flux Analyzer. These protocols allowed us to simultaneously assess the direct effects of metabolites and inhibitors on mitochondrial respiration and glycolytic activity in real-time with the readout of oxygen consumption rate and extracellular acidification rate. Using saponin-freed parasites at the schizont stage, we found that succinate, malate, glycerol-3-phosphate, and glutamate, but not pyruvate, were able to increase the oxygen consumption rate and that glycerol-3-phosphate dehydrogenase had the largest potential as an electron donor among tested mitochondrial dehydrogenases. Furthermore, we revealed the presence of a glucose-regulated metabolic shift between oxidative phosphorylation and glycolysis. We measured proton leak and reserve capacity and found bioenergetic evidence for oxidative phosphorylation in erythrocytic stage parasites but at a level much lower than that observed in mammalian cells. Lastly, we developed an assay platform for target identification and mode of action studies of mitochondria-targeting antimalarials. This study provides new insights into the bioenergetics and metabolomics of the Plasmodium mitochondria.
Collapse
Affiliation(s)
- Tomoyo Sakata-Kato
- Department of Immunology and Infectious Diseases, Harvard T.H. Chan School of Public Health, Boston, Massachusetts 02115, United States
| | - Dyann F. Wirth
- Department of Immunology and Infectious Diseases, Harvard T.H. Chan School of Public Health, Boston, Massachusetts 02115, United States
| |
Collapse
|
29
|
Volkman SK, Herman J, Lukens AK, Hartl DL. Genome-Wide Association Studies of Drug-Resistance Determinants. Trends Parasitol 2016; 33:214-230. [PMID: 28179098 DOI: 10.1016/j.pt.2016.10.001] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/15/2016] [Revised: 09/26/2016] [Accepted: 10/06/2016] [Indexed: 02/07/2023]
Abstract
Population genetic strategies that leverage association, selection, and linkage have identified drug-resistant loci. However, challenges and limitations persist in identifying drug-resistance loci in malaria. In this review we discuss the genetic basis of drug resistance and the use of genome-wide association studies, complemented by selection and linkage studies, to identify and understand mechanisms of drug resistance and response. We also discuss the implications of nongenetic mechanisms of drug resistance recently reported in the literature, and present models of the interplay between nongenetic and genetic processes that contribute to the emergence of drug resistance. Throughout, we examine artemisinin resistance as an example to emphasize challenges in identifying phenotypes suitable for population genetic studies as well as complications due to multiple-factor drug resistance.
Collapse
Affiliation(s)
- Sarah K Volkman
- Harvard T.H. Chan School of Public Health, Department of Immunology and Infectious Disease, Boston, MA, USA; The Broad Institute of MIT and Harvard, Infectious Disease Initiative, Cambridge, MA, USA; Simmons College, School of Nursing and Health Science, Boston, MA, USA.
| | - Jonathan Herman
- Harvard T.H. Chan School of Public Health, Department of Immunology and Infectious Disease, Boston, MA, USA; Weill Department of Medicine, Weill Cornell Medical College, New York, NY, USA
| | - Amanda K Lukens
- Harvard T.H. Chan School of Public Health, Department of Immunology and Infectious Disease, Boston, MA, USA; The Broad Institute of MIT and Harvard, Infectious Disease Initiative, Cambridge, MA, USA
| | - Daniel L Hartl
- The Broad Institute of MIT and Harvard, Infectious Disease Initiative, Cambridge, MA, USA; Harvard University, Organismic and Evolutionary Biology, Cambridge, MA, USA
| |
Collapse
|
30
|
Atovaquone and ELQ-300 Combination Therapy as a Novel Dual-Site Cytochrome bc1 Inhibition Strategy for Malaria. Antimicrob Agents Chemother 2016; 60:4853-9. [PMID: 27270285 DOI: 10.1128/aac.00791-16] [Citation(s) in RCA: 41] [Impact Index Per Article: 5.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/07/2016] [Accepted: 05/24/2016] [Indexed: 12/31/2022] Open
Abstract
Antimalarial combination therapies play a crucial role in preventing the emergence of drug-resistant Plasmodium parasites. Although artemisinin-based combination therapies (ACTs) comprise the majority of these formulations, inhibitors of the mitochondrial cytochrome bc1 complex (cyt bc1) are among the few compounds that are effective for both acute antimalarial treatment and prophylaxis. There are two known sites for inhibition within cyt bc1: atovaquone (ATV) blocks the quinol oxidase (Qo) site of cyt bc1, while some members of the endochin-like quinolone (ELQ) family, including preclinical candidate ELQ-300, inhibit the quinone reductase (Qi) site and retain full potency against ATV-resistant Plasmodium falciparum strains with Qo site mutations. Here, we provide the first in vivo comparison of ATV, ELQ-300, and combination therapy consisting of ATV plus ELQ-300 (ATV:ELQ-300), using P. yoelii murine models of malaria. In our monotherapy assessments, we found that ATV functioned as a single-dose curative compound in suppressive tests whereas ELQ-300 demonstrated a unique cumulative dosing effect that successfully blocked recrudescence even in a high-parasitemia acute infection model. ATV:ELQ-300 therapy was highly synergistic, and the combination was curative with a single combined dose of 1 mg/kg of body weight. Compared to the ATV:proguanil (Malarone) formulation, ATV:ELQ-300 was more efficacious in multiday, acute infection models and was equally effective at blocking the emergence of ATV-resistant parasites. Ultimately, our data suggest that dual-site inhibition of cyt bc1 is a valuable strategy for antimalarial combination therapy and that Qi site inhibitors such as ELQ-300 represent valuable partner drugs for the clinically successful Qo site inhibitor ATV.
Collapse
|
31
|
Raphemot R, Posfai D, Derbyshire ER. Current therapies and future possibilities for drug development against liver-stage malaria. J Clin Invest 2016; 126:2013-20. [PMID: 27249674 DOI: 10.1172/jci82981] [Citation(s) in RCA: 26] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/11/2023] Open
Abstract
Malaria remains a global public health threat, with half of the world's population at risk. Despite numerous efforts in the past decade to develop new antimalarial drugs to surmount increasing resistance to common therapies, challenges remain in the expansion of the current antimalarial arsenal for the elimination of this disease. The requirement of prophylactic and radical cure activities for the next generation of antimalarial drugs demands that new research models be developed to support the investigation of the elusive liver stage of the malaria parasite. In this Review, we revisit current antimalarial therapies and discuss recent advances for in vitro and in vivo malaria research models of the liver stage and their importance in probing parasite biology and the discovery of novel drug candidates.
Collapse
|
32
|
Goodman CD, Siregar JE, Mollard V, Vega-Rodríguez J, Syafruddin D, Matsuoka H, Matsuzaki M, Toyama T, Sturm A, Cozijnsen A, Jacobs-Lorena M, Kita K, Marzuki S, McFadden GI. Parasites resistant to the antimalarial atovaquone fail to transmit by mosquitoes. Science 2016; 352:349-53. [PMID: 27081071 DOI: 10.1126/science.aad9279] [Citation(s) in RCA: 95] [Impact Index Per Article: 11.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/23/2015] [Accepted: 03/10/2016] [Indexed: 12/16/2022]
Abstract
Drug resistance compromises control of malaria. Here, we show that resistance to a commonly used antimalarial medication, atovaquone, is apparently unable to spread. Atovaquone pressure selects parasites with mutations in cytochrome b, a respiratory protein with low but essential activity in the mammalian blood phase of the parasite life cycle. Resistance mutations rescue parasites from the drug but later prove lethal in the mosquito phase, where parasites require full respiration. Unable to respire efficiently, resistant parasites fail to complete mosquito development, arresting their life cycle. Because cytochrome b is encoded by the maternally inherited parasite mitochondrion, even outcrossing with wild-type strains cannot facilitate spread of resistance. Lack of transmission suggests that resistance will be unable to spread in the field, greatly enhancing the utility of atovaquone in malaria control.
Collapse
Affiliation(s)
| | - Josephine E Siregar
- School of BioSciences, University of Melbourne, Melbourne, VIC 3010, Australia. Eijkman Institute for Molecular Biology, JI Diponegoro no. 69, Jakarta, 10430, Indonesia. Department of Biomedical Chemistry, Graduate School of Medicine, The University of Tokyo, Hongo, Bunkyo-ku, Tokyo 113-0033, Japan
| | - Vanessa Mollard
- School of BioSciences, University of Melbourne, Melbourne, VIC 3010, Australia
| | - Joel Vega-Rodríguez
- Johns Hopkins University Bloomberg School of Public Health, Department of Molecular Microbiology and Immunology, Malaria Research Institute, Baltimore, MD 21205, USA
| | - Din Syafruddin
- Eijkman Institute for Molecular Biology, JI Diponegoro no. 69, Jakarta, 10430, Indonesia. Department of Parasitology, Faculty of Medicine, Hasanuddin University, Jalan Perintis Kemerdekaan Km10, Makassar 90245, Indonesia
| | - Hiroyuki Matsuoka
- Division of Medical Zoology, Jichi Medical University, 3311-1 Yakushiji, Shimotsuke, Tochigi 329-0498, Japan
| | - Motomichi Matsuzaki
- Department of Biomedical Chemistry, Graduate School of Medicine, The University of Tokyo, Hongo, Bunkyo-ku, Tokyo 113-0033, Japan
| | - Tomoko Toyama
- School of BioSciences, University of Melbourne, Melbourne, VIC 3010, Australia
| | - Angelika Sturm
- School of BioSciences, University of Melbourne, Melbourne, VIC 3010, Australia
| | - Anton Cozijnsen
- School of BioSciences, University of Melbourne, Melbourne, VIC 3010, Australia
| | - Marcelo Jacobs-Lorena
- Johns Hopkins University Bloomberg School of Public Health, Department of Molecular Microbiology and Immunology, Malaria Research Institute, Baltimore, MD 21205, USA
| | - Kiyoshi Kita
- Department of Biomedical Chemistry, Graduate School of Medicine, The University of Tokyo, Hongo, Bunkyo-ku, Tokyo 113-0033, Japan. School of Tropical Medicine and Global Health, Nagasaki University, Sakamoto, Nagasaki 852-8523, Japan
| | - Sangkot Marzuki
- Eijkman Institute for Molecular Biology, JI Diponegoro no. 69, Jakarta, 10430, Indonesia
| | - Geoffrey I McFadden
- School of BioSciences, University of Melbourne, Melbourne, VIC 3010, Australia.
| |
Collapse
|
33
|
Brogi S, Giovani S, Brindisi M, Gemma S, Novellino E, Campiani G, Blackman MJ, Butini S. In silico study of subtilisin-like protease 1 (SUB1) from different Plasmodium species in complex with peptidyl-difluorostatones and characterization of potent pan-SUB1 inhibitors. J Mol Graph Model 2016; 64:121-130. [PMID: 26826801 PMCID: PMC5276822 DOI: 10.1016/j.jmgm.2016.01.005] [Citation(s) in RCA: 16] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/23/2015] [Revised: 12/04/2015] [Accepted: 01/16/2016] [Indexed: 11/23/2022]
Abstract
Homology models of four SUB1 orthologues from P. falciparum species were produced. We analyzed the binding mode of our previous difluorostatone inhibitors to six SUB1. In vitro activity of our difluorostatone-based inhibitors was correctly predicted. We derived a structure-based pan-SUB1 pharmacophore, and validated it in silico. We confirmed that development of pan-SUB1 inhibitors is a feasible task.
Plasmodium falciparum subtilisin-like protease 1 (SUB1) is a novel target for the development of innovative antimalarials. We recently described the first potent difluorostatone-based inhibitors of the enzyme ((4S)-(N-((N-acetyl-l-lysyl)-l-isoleucyl-l-threonyl-l-alanyl)-2,2-difluoro-3-oxo-4-aminopentanoyl)glycine (1) and (4S)-(N-((N-acetyl-l-isoleucyl)-l-threonyl-l-alanylamino)-2,2-difluoro-3-oxo-4-aminopentanoyl)glycine (2)). As a continuation of our efforts towards the definition of the molecular determinants of enzyme-inhibitor interaction, we herein propose the first comprehensive computational investigation of the SUB1 catalytic core from six different Plasmodium species, using homology modeling and molecular docking approaches. Investigation of the differences in the binding sites as well as the interactions of our inhibitors 1,2 with all SUB1 orthologues, allowed us to highlight the structurally relevant regions of the enzyme that could be targeted for developing pan-SUB1 inhibitors. According to our in silico predictions, compounds 1,2 have been demonstrated to be potent inhibitors of SUB1 from all three major clinically relevant Plasmodium species (P. falciparum, P. vivax, and P. knowlesi). We next derived multiple structure-based pharmacophore models that were combined in an inclusive pan-SUB1 pharmacophore (SUB1-PHA). This latter was validated by applying in silico methods, showing that it may be useful for the future development of potent antimalarial agents.
Collapse
Affiliation(s)
- Simone Brogi
- European Research Centre for Drug Discovery and Development (NatSynDrugs), University of Siena, via Aldo Moro 2, 53100, Siena, Italy; Dipartimento di Biotecnologie, Chimica e Farmacia, University of Siena, via Aldo Moro 2, 53100, Siena, Italy; Centro Interuniversitario di Ricerche sulla Malaria (CIRM), University of Perugia, Perugia, Italy
| | - Simone Giovani
- European Research Centre for Drug Discovery and Development (NatSynDrugs), University of Siena, via Aldo Moro 2, 53100, Siena, Italy; Dipartimento di Biotecnologie, Chimica e Farmacia, University of Siena, via Aldo Moro 2, 53100, Siena, Italy; Centro Interuniversitario di Ricerche sulla Malaria (CIRM), University of Perugia, Perugia, Italy
| | - Margherita Brindisi
- European Research Centre for Drug Discovery and Development (NatSynDrugs), University of Siena, via Aldo Moro 2, 53100, Siena, Italy; Dipartimento di Biotecnologie, Chimica e Farmacia, University of Siena, via Aldo Moro 2, 53100, Siena, Italy; Centro Interuniversitario di Ricerche sulla Malaria (CIRM), University of Perugia, Perugia, Italy
| | - Sandra Gemma
- European Research Centre for Drug Discovery and Development (NatSynDrugs), University of Siena, via Aldo Moro 2, 53100, Siena, Italy; Dipartimento di Biotecnologie, Chimica e Farmacia, University of Siena, via Aldo Moro 2, 53100, Siena, Italy; Centro Interuniversitario di Ricerche sulla Malaria (CIRM), University of Perugia, Perugia, Italy.
| | - Ettore Novellino
- European Research Centre for Drug Discovery and Development (NatSynDrugs), University of Siena, via Aldo Moro 2, 53100, Siena, Italy; Dipartimento di Farmacia, University of Naples Federico II, Via D. Montesano 49, 80131, Naples, Italy
| | - Giuseppe Campiani
- European Research Centre for Drug Discovery and Development (NatSynDrugs), University of Siena, via Aldo Moro 2, 53100, Siena, Italy; Dipartimento di Biotecnologie, Chimica e Farmacia, University of Siena, via Aldo Moro 2, 53100, Siena, Italy; Centro Interuniversitario di Ricerche sulla Malaria (CIRM), University of Perugia, Perugia, Italy.
| | - Michael J Blackman
- Division of Parasitology, MRC National Institute for Medical Research, Mill Hill, London NW7 1AA, UK
| | - Stefania Butini
- European Research Centre for Drug Discovery and Development (NatSynDrugs), University of Siena, via Aldo Moro 2, 53100, Siena, Italy; Dipartimento di Biotecnologie, Chimica e Farmacia, University of Siena, via Aldo Moro 2, 53100, Siena, Italy; Centro Interuniversitario di Ricerche sulla Malaria (CIRM), University of Perugia, Perugia, Italy
| |
Collapse
|
34
|
Electron Transfer Reactions at the Qo Site of the Cytochrome bc 1 Complex: The Good, the Bad, and the Ugly. ADVANCES IN PHOTOSYNTHESIS AND RESPIRATION 2016. [DOI: 10.1007/978-94-017-7481-9_21] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/13/2023]
|
35
|
Within-Host Selection of Drug Resistance in a Mouse Model of Repeated Incomplete Malaria Treatment: Comparison between Atovaquone and Pyrimethamine. Antimicrob Agents Chemother 2015; 60:258-63. [PMID: 26503662 DOI: 10.1128/aac.00538-15] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/23/2015] [Accepted: 09/05/2015] [Indexed: 11/20/2022] Open
Abstract
The evolutionary selection of malaria parasites within individual hosts is an important factor in the emergence of drug resistance but is still not well understood. We have examined the selection process for drug resistance in the mouse malaria agent Plasmodium berghei and compared the dynamics of the selection for atovaquone and pyrimethamine. Resistance to these drugs has been shown to be associated with genetic lesions in the dihydrofolate reductase gene in the case of pyrimethamine and in the mitochondrial cytochrome b gene for atovaquone. A mouse malaria model for the selection of drug resistance, based on repeated incomplete treatment (RICT) with a therapeutic dose of antimalarial drugs, was established. The number of treatment cycles for the development of stable resistance to atovaquone (2.47 ± 0.70; n = 19) was found to be significantly lower than for pyrimethamine (5.44 ± 1.46; n = 16; P < 0.0001), even when the parental P. berghei Leiden strain was cloned prior to the resistance selection. Similar results were obtained with P. berghei Edinburgh. Mutational changes underlying the resistance were identified to be S110N in dihydrofolate reductase for pyrimethamine and Y268N, Y268C, Y268S, L271V-K272R, and G280D in cytochrome b for atovaquone. These results are consistent with the rate of mitochondrial DNA mutation being higher than that in the nucleus and suggest that mutation leading to pyrimethamine resistance is not a rare event.
Collapse
|
36
|
Song Z, Clain J, Iorga BI, Vallières C, Lalève A, Fisher N, Meunier B. Interplay between the hinge region of iron sulphur protein and the Qo site in the bc1 complex - Analysis of Plasmodium-like mutations in the yeast enzyme. BIOCHIMICA ET BIOPHYSICA ACTA-BIOENERGETICS 2015; 1847:1487-94. [PMID: 26301481 DOI: 10.1016/j.bbabio.2015.08.005] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/27/2015] [Revised: 07/21/2015] [Accepted: 08/19/2015] [Indexed: 10/23/2022]
Abstract
The respiratory chain bc1 complex is central to mitochondrial bioenergetics and the target of antiprotozoals. We characterized a modified yeast bc1 complex that more closely resemble Plasmodium falciparum enzyme. The mutant version was generated by replacing ten cytochrome b Qo site residues by P. falciparum equivalents. The Plasmodium-like changes caused a major dysfunction of the catalytic mechanism of the bc1 complex resulting in superoxide overproduction and respiratory growth defect. The defect was corrected by substitution of the conserved residue Y279 by a phenylalanine, or by mutations in or in the vicinity of the hinge domain of the iron-sulphur protein. It thus appears that side-reactions can be prevented by the substitution Y279F or the modification of the iron-sulphur protein hinge region. Interestingly, P. falciparum - and all the apicomplexan - contains an unusual hinge region. We replaced the yeast hinge region by the Plasmodium version and combined it with the Plasmodium-like version of the Qo site. This combination restored the respiratory growth competence. It could be suggested that, in the apicomplexan, the hinge region and the cytochrome b Qo site have co-evolved to maintain catalytic efficiency of the bc1 complex Qo site.
Collapse
Affiliation(s)
- Zehua Song
- Institute for Integrative Biology of the Cell (I2BC), CEA, CNRS, Université Paris-Sud, 91198 Gif-sur-Yvette, France
| | - Jérôme Clain
- UMR 216, Faculté de Pharmacie de Paris, Université Paris Descartes, and Institut de Recherche pour le Développement, 75006 Paris, France
| | - Bogdan I Iorga
- Institut de Chimie des Substances Naturelles, CNRS, UPR 2301, Labex LERMIT, 91198 Gif-sur-Yvette, France
| | - Cindy Vallières
- Institute for Integrative Biology of the Cell (I2BC), CEA, CNRS, Université Paris-Sud, 91198 Gif-sur-Yvette, France
| | - Anaïs Lalève
- Institute for Integrative Biology of the Cell (I2BC), CEA, CNRS, Université Paris-Sud, 91198 Gif-sur-Yvette, France
| | - Nicholas Fisher
- Plant Research Laboratory, Michigan State University, East Lansing, MI 48824, USA..
| | - Brigitte Meunier
- Institute for Integrative Biology of the Cell (I2BC), CEA, CNRS, Université Paris-Sud, 91198 Gif-sur-Yvette, France.
| |
Collapse
|
37
|
Flaherty BR, Wang Y, Trope EC, Ho TG, Muralidharan V, Kennedy EJ, Peterson DS. The Stapled AKAP Disruptor Peptide STAD-2 Displays Antimalarial Activity through a PKA-Independent Mechanism. PLoS One 2015; 10:e0129239. [PMID: 26010880 PMCID: PMC4444124 DOI: 10.1371/journal.pone.0129239] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/03/2015] [Accepted: 05/06/2015] [Indexed: 11/19/2022] Open
Abstract
Drug resistance poses a significant threat to ongoing malaria control efforts. Coupled with lack of a malaria vaccine, there is an urgent need for the development of new antimalarials with novel mechanisms of action and low susceptibility to parasite drug resistance. Protein Kinase A (PKA) has been implicated as a critical regulator of pathogenesis in malaria. Therefore, we sought to investigate the effects of disrupted PKA signaling as a possible strategy for inhibition of parasite replication. Host PKA activity is partly regulated by a class of proteins called A Kinase Anchoring Proteins (AKAPs), and interaction between HsPKA and AKAP can be inhibited by the stapled peptide Stapled AKAP Disruptor 2 (STAD-2). STAD-2 was tested for permeability to and activity against Plasmodium falciparum blood stage parasites in vitro. The compound was selectively permeable only to infected red blood cells (iRBC) and demonstrated rapid antiplasmodial activity, possibly via iRBC lysis (IC50 ≈ 1 μM). STAD-2 localized within the parasite almost immediately post-treatment but showed no evidence of direct association with PKA, indicating that STAD-2 acts via a PKA-independent mechanism. Furosemide-insensitive parasite permeability pathways in the iRBC were largely responsible for uptake of STAD-2. Further, peptide import was highly specific to STAD-2 as evidenced by low permeability of control stapled peptides. Selective uptake and antiplasmodial activity of STAD-2 provides important groundwork for the development of stapled peptides as potential antimalarials. Such peptides may also offer an alternative strategy for studying protein-protein interactions critical to parasite development and pathogenesis.
Collapse
Affiliation(s)
- Briana R. Flaherty
- Department of Infectious Diseases, University of Georgia College of Veterinary Medicine, Athens, Georgia, United States of America
- Center for Tropical and Emerging Global Diseases, University of Georgia, Athens, Georgia, United States of America
| | - Yuxiao Wang
- Department of Pharmaceutical and Biomedical Sciences, College of Pharmacy, University of Georgia, Athens, Georgia, United States of America
| | - Edward C. Trope
- Department of Infectious Diseases, University of Georgia College of Veterinary Medicine, Athens, Georgia, United States of America
| | - Tienhuei G. Ho
- Department of Pharmaceutical and Biomedical Sciences, College of Pharmacy, University of Georgia, Athens, Georgia, United States of America
| | - Vasant Muralidharan
- Center for Tropical and Emerging Global Diseases, University of Georgia, Athens, Georgia, United States of America
- Department of Cellular Biology, University of Georgia, Athens, Georgia, United States of America
| | - Eileen J. Kennedy
- Department of Pharmaceutical and Biomedical Sciences, College of Pharmacy, University of Georgia, Athens, Georgia, United States of America
- * E-mail: (EK); David Peterson: (DP)
| | - David S. Peterson
- Department of Infectious Diseases, University of Georgia College of Veterinary Medicine, Athens, Georgia, United States of America
- Center for Tropical and Emerging Global Diseases, University of Georgia, Athens, Georgia, United States of America
- * E-mail: (EK); David Peterson: (DP)
| |
Collapse
|
38
|
Saccharomyces cerevisiae-based mutational analysis of the bc1 complex Qo site residue 279 to study the trade-off between atovaquone resistance and function. Antimicrob Agents Chemother 2015; 59:4053-8. [PMID: 25918152 DOI: 10.1128/aac.00710-15] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/26/2015] [Accepted: 04/19/2015] [Indexed: 11/20/2022] Open
Abstract
The bc1 complex is central to mitochondrial bioenergetics and the target of the antimalarial drug atovaquone that binds in the quinol oxidation (Qo) site of the complex. Structural analysis has shown that the Qo site residue Y279 (Y268 in Plasmodium falciparum) is key for atovaquone binding. Consequently, atovaquone resistance can be acquired by mutation of that residue. In addition to the probability of amino acid substitution, the level of atovaquone resistance and the loss of bc1 complex activity that are associated with the novel amino acid would restrict the nature of resistance-driven mutations occurring on atovaquone exposure in native parasite populations. Using the yeast model, we characterized the effect of all the amino acid replacements resulting from a single nucleotide substitution at codon 279: Y279C, Y279D, Y279F, Y279H, Y279N, and Y279S (Y279C, D, F, H, N, and S). Two residue changes that required a double nucleotide substitution, Y279A and W, were added to the series. We found that mutations Y279A, C, and S conferred high atovaquone resistance but decreased the catalytic activity. Y279F had wild-type enzymatic activity and sensitivity to atovaquone, while the other substitutions caused a dramatic respiratory defect. The results obtained with the yeast model were examined in regard to atomic structure and compared to the reported data on the evolution of acquired atovaquone resistance in P. falciparum.
Collapse
|
39
|
Ingasia LA, Akala HM, Imbuga MO, Opot BH, Eyase FL, Johnson JD, Bulimo WD, Kamau E. Molecular characterization of the cytochrome b gene and in vitro atovaquone susceptibility of Plasmodium falciparum isolates from Kenya. Antimicrob Agents Chemother 2015; 59:1818-21. [PMID: 25583715 PMCID: PMC4325819 DOI: 10.1128/aac.03956-14] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/24/2014] [Accepted: 01/04/2015] [Indexed: 11/20/2022] Open
Abstract
The prevalence of a genetic polymorphism(s) at codon 268 in the cytochrome b gene, which is associated with failure of atovaquone-proguanil treatment, was analyzed in 227 Plasmodium falciparum parasites from western Kenya. The prevalence of the wild-type allele was 63%, and that of the Y268S (denoting a Y-to-S change at position 268) mutant allele was 2%. There were no pure Y268C or Y268N mutant alleles, only mixtures of a mutant allele(s) with the wild type. There was a correlation between parasite 50% inhibitory concentration (IC50) and parasite genetic polymorphism; mutant alleles had higher IC50s than the wild type.
Collapse
Affiliation(s)
- Luicer A Ingasia
- Department of Emerging Infectious Diseases-Global Emerging Infections Surveillance and Response System (DEID-GEIS) Program, U.S. Army Medical Research Unit-Kenya (USAMRU-K), Kenya Medical Research Institute (KEMRI)-Walter Reed Project, Kisumu, Kenya
| | - Hoseah M Akala
- Department of Emerging Infectious Diseases-Global Emerging Infections Surveillance and Response System (DEID-GEIS) Program, U.S. Army Medical Research Unit-Kenya (USAMRU-K), Kenya Medical Research Institute (KEMRI)-Walter Reed Project, Kisumu, Kenya
| | - Mabel O Imbuga
- Department of Biochemistry, College of Health Sciences, Jomo Kenyatta University of Agriculture and Technology, Nairobi, Kenya
| | - Benjamin H Opot
- Department of Emerging Infectious Diseases-Global Emerging Infections Surveillance and Response System (DEID-GEIS) Program, U.S. Army Medical Research Unit-Kenya (USAMRU-K), Kenya Medical Research Institute (KEMRI)-Walter Reed Project, Kisumu, Kenya
| | - Fredrick L Eyase
- Department of Emerging Infectious Diseases-Global Emerging Infections Surveillance and Response System (DEID-GEIS) Program, U.S. Army Medical Research Unit-Kenya (USAMRU-K), Kenya Medical Research Institute (KEMRI)-Walter Reed Project, Kisumu, Kenya
| | - Jacob D Johnson
- Department of Emerging Infectious Diseases-Global Emerging Infections Surveillance and Response System (DEID-GEIS) Program, U.S. Army Medical Research Unit-Kenya (USAMRU-K), Kenya Medical Research Institute (KEMRI)-Walter Reed Project, Kisumu, Kenya
| | - Wallace D Bulimo
- Department of Emerging Infectious Diseases-Global Emerging Infections Surveillance and Response System (DEID-GEIS) Program, U.S. Army Medical Research Unit-Kenya (USAMRU-K), Kenya Medical Research Institute (KEMRI)-Walter Reed Project, Kisumu, Kenya
| | - Edwin Kamau
- Department of Emerging Infectious Diseases-Global Emerging Infections Surveillance and Response System (DEID-GEIS) Program, U.S. Army Medical Research Unit-Kenya (USAMRU-K), Kenya Medical Research Institute (KEMRI)-Walter Reed Project, Kisumu, Kenya
| |
Collapse
|
40
|
Abstract
Cytochrome bc1 is a proven drug target in the prevention and treatment of malaria. The rise in drug-resistant strains of Plasmodium falciparum, the organism responsible for malaria, has generated a global effort in designing new classes of drugs. Much of the design/redesign work on overcoming this resistance has been focused on compounds that are presumed to bind the Q(o) site (one of two potential binding sites within cytochrome bc1 using the known crystal structure of this large membrane-bound macromolecular complex via in silico modeling. Cocrystallization of the cytochrome bc1 complex with the 4(1H)-pyridone class of inhibitors, GSK932121 and GW844520, that have been shown to be potent antimalarial agents in vivo, revealed that these inhibitors do not bind at the Q(o) site but bind at the Q(i )site. The discovery that these compounds bind at the Q(i) site may provide a molecular explanation for the cardiotoxicity and eventual failure of GSK932121 in phase-1 clinical trial and highlight the need for direct experimental observation of a compound bound to a target site before chemical optimization and development for clinical trials. The binding of the 4(1H)-pyridone class of inhibitors to Q(i) also explains the ability of this class to overcome parasite Q(o)-based atovaquone resistance and provides critical structural information for future design of new selective compounds with improved safety profiles.
Collapse
|
41
|
Atovaquone tolerance in Plasmodium falciparum parasites selected for high-level resistance to a dihydroorotate dehydrogenase inhibitor. Antimicrob Agents Chemother 2014; 59:686-9. [PMID: 25331708 DOI: 10.1128/aac.02347-14] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/21/2022] Open
Abstract
Atovaquone is a component of Malarone, a widely prescribed antimalarial combination, that targets malaria respiration. Here we show that parasites with high-level resistance to an inhibitor of dihydroorotate dehydrogenase demonstrate unexpected atovaquone tolerance. Fortunately, the tolerance is diminished with proguanil, the second partner in Malarone. It is important to understand such "genetic cross talk" between respiration and pyrimidine biosynthesis since many antimalarial drug development programs target these two seemingly independent pathways.
Collapse
|
42
|
Akhoon BA, Singh KP, Varshney M, Gupta SK, Shukla Y, Gupta SK. Understanding the mechanism of atovaquone drug resistance in Plasmodium falciparum cytochrome b mutation Y268S using computational methods. PLoS One 2014; 9:e110041. [PMID: 25334024 PMCID: PMC4198183 DOI: 10.1371/journal.pone.0110041] [Citation(s) in RCA: 22] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/10/2013] [Accepted: 09/15/2014] [Indexed: 11/25/2022] Open
Abstract
The rapid appearance of resistant malarial parasites after introduction of atovaquone (ATQ) drug has prompted the search for new drugs as even single point mutations in the active site of Cytochrome b protein can rapidly render ATQ ineffective. The presence of Y268 mutations in the Cytochrome b (Cyt b) protein is previously suggested to be responsible for the ATQ resistance in Plasmodium falciparum (P. falciparum). In this study, we examined the resistance mechanism against ATQ in P. falciparum through computational methods. Here, we reported a reliable protein model of Cyt bc1 complex containing Cyt b and the Iron-Sulphur Protein (ISP) of P. falciparum using composite modeling method by combining threading, ab initio modeling and atomic-level structure refinement approaches. The molecular dynamics simulations suggest that Y268S mutation causes ATQ resistance by reducing hydrophobic interactions between Cyt bc1 protein complex and ATQ. Moreover, the important histidine contact of ATQ with the ISP chain is also lost due to Y268S mutation. We noticed the induced mutation alters the arrangement of active site residues in a fashion that enforces ATQ to find its new stable binding site far away from the wild-type binding pocket. The MM-PBSA calculations also shows that the binding affinity of ATQ with Cyt bc1 complex is enough to hold it at this new site that ultimately leads to the ATQ resistance.
Collapse
Affiliation(s)
- Bashir A. Akhoon
- Department of Bioinformatics, Systems Toxicology Group, CSIR-Indian Institute of Toxicology Research, Lucknow, India
| | - Krishna P. Singh
- Department of Bioinformatics, Systems Toxicology Group, CSIR-Indian Institute of Toxicology Research, Lucknow, India
| | - Megha Varshney
- Interdisciplinary Biotechnology Unit, Aligarh Muslim University, Aligarh, India
| | - Shishir K. Gupta
- Department of Bioinformatics, Biocenter, Am Hubland, University of Würzburg, Würzburg, Germany
| | - Yogeshwar Shukla
- Department of Proteomics, CSIR-Indian Institute of Toxicology Research, Lucknow, India
- Academy of Scientific and Innovative Research (AcSIR), New Delhi, India
| | - Shailendra K. Gupta
- Department of Bioinformatics, Systems Toxicology Group, CSIR-Indian Institute of Toxicology Research, Lucknow, India
- Academy of Scientific and Innovative Research (AcSIR), New Delhi, India
- * E-mail:
| |
Collapse
|
43
|
Siregar JE, Kurisu G, Kobayashi T, Matsuzaki M, Sakamoto K, Mi-ichi F, Watanabe YI, Hirai M, Matsuoka H, Syafruddin D, Marzuki S, Kita K. Direct evidence for the atovaquone action on the Plasmodium cytochrome bc1 complex. Parasitol Int 2014; 64:295-300. [PMID: 25264100 DOI: 10.1016/j.parint.2014.09.011] [Citation(s) in RCA: 57] [Impact Index Per Article: 5.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/28/2014] [Revised: 09/09/2014] [Accepted: 09/15/2014] [Indexed: 11/16/2022]
Abstract
Atovaquone, a coenzyme Q analogue has been indicated to specifically target the cytochrome bc1 complex of the mitochondrial respiratory chain in the malarial parasite and other protozoan. Various mutations in the quinone binding site of the cytochrome b gene of Plasmodium spp. such as M133I, L144S, L271V, K272R, Y268C, Y268S, Y268N, and V284F are suggesting to associate with resistance to atovaquone. There is no direct evidence of relation between the mutations and resistance to atovaquone in Plasmodium parasite that has been available. Technical difficulties in isolating active assayable mitochondria in the malarial parasite hinder us to obtain direct biochemical evidence to support the relation between the mutations and drug resistance. The establishment of a mitochondrial isolation method for the malaria parasite has allowed us to test the degree of resistance of Plasmodium berghei isolates to atovaquone directly. We have tested the activity of dihydroorotate (DHO)-cytochrome c reductase in various P. berghei atovaquone resistant clones in the presence of a wide concentration range of atovaquone. Our results show the IC(50) of P. berghei atovaquone resistant clones is much higher (1.5 up to 40 nM) in comparison to the atovaquone sensitive clones (0.132-0.465 nM). The highest IC(50) was revealed in clones carrying Y268C and Y268N mutations (which play an important role in atovaquone resistance in Plasmodium falciparum), with an approximately 100-fold increase. The findings indicate the importance of the mutation in the quinone binding site of the cytochrome b gene and that provide a direct evidence for the atovaquone inhibitory mechanism in the cytochrome bc1 complex of the parasite.
Collapse
Affiliation(s)
- Josephine E Siregar
- Eijkman Institute for Molecular Biology, Jl. Diponegoro 69, Jakarta 10430, Indonesia
| | - Genji Kurisu
- Institute for Protein Research, Osaka University, Suita, Osaka 565-0871, Japan
| | - Tamaki Kobayashi
- Department of Biomedical Chemistry, Graduate School of Medicine, The University of Tokyo, Hongo, Bunkyo-ku, Tokyo 113-0033, Japan
| | - Motomichi Matsuzaki
- Department of Biomedical Chemistry, Graduate School of Medicine, The University of Tokyo, Hongo, Bunkyo-ku, Tokyo 113-0033, Japan
| | - Kimitoshi Sakamoto
- Department of Biomedical Chemistry, Graduate School of Medicine, The University of Tokyo, Hongo, Bunkyo-ku, Tokyo 113-0033, Japan
| | - Fumika Mi-ichi
- Department of Biomedical Chemistry, Graduate School of Medicine, The University of Tokyo, Hongo, Bunkyo-ku, Tokyo 113-0033, Japan
| | - Yoh-ichi Watanabe
- Department of Biomedical Chemistry, Graduate School of Medicine, The University of Tokyo, Hongo, Bunkyo-ku, Tokyo 113-0033, Japan
| | - Makoto Hirai
- Department of Medical Zoology, Jichi Medical School, Minami-kawachi, Tochigi 329-0498, Japan
| | - Hiroyuki Matsuoka
- Department of Medical Zoology, Jichi Medical School, Minami-kawachi, Tochigi 329-0498, Japan
| | - Din Syafruddin
- Eijkman Institute for Molecular Biology, Jl. Diponegoro 69, Jakarta 10430, Indonesia
| | - Sangkot Marzuki
- Eijkman Institute for Molecular Biology, Jl. Diponegoro 69, Jakarta 10430, Indonesia
| | - Kiyoshi Kita
- Department of Biomedical Chemistry, Graduate School of Medicine, The University of Tokyo, Hongo, Bunkyo-ku, Tokyo 113-0033, Japan.
| |
Collapse
|
44
|
Abstract
Due to an increased need for new antimalarial chemotherapies that show potency against Plasmodium falciparum, researchers are targeting new processes within the parasite in an effort to circumvent or delay the onset of drug resistance. One such promising area for antimalarial drug development has been the parasite mitochondrial electron transport chain (ETC). Efforts have been focused on targeting key processes along the parasite ETC specifically the dihydroorotate dehydrogenase (DHOD) enzyme, the cytochrome bc 1 enzyme and the NADH type II oxidoreductase (PfNDH2) pathway. This review summarizes the most recent efforts in antimalarial drug development reported in the literature and describes the evolution of these compounds.
Collapse
|
45
|
Plucinski MM, Huber CS, Akinyi S, Dalton W, Eschete M, Grady K, Silva-Flannery L, Mathison BA, Udhayakumar V, Arguin PM, Barnwell JW. Novel Mutation in Cytochrome B of Plasmodium falciparum in One of Two Atovaquone-Proguanil Treatment Failures in Travelers Returning From Same Site in Nigeria. Open Forum Infect Dis 2014; 1:ofu059. [PMID: 25734129 PMCID: PMC4281801 DOI: 10.1093/ofid/ofu059] [Citation(s) in RCA: 26] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/21/2014] [Accepted: 07/01/2014] [Indexed: 11/14/2022] Open
Abstract
Background Atovaquone-proguanil (AP) is the most commonly used treatment for uncomplicated Plasmodium falciparum malaria in the United States. Apparent AP treatment failures were reported 7 months apart in 2 American travelers who stayed in the same compound for foreign workers in Rivers State, Nigeria. Methods We analyzed pretreatment (day 0) and day of failure samples from both travelers for mutations in the P falciparum cytochrome B (pfcytb) and dihydrofolate reductase (pfdhfr) genes associated with resistance to atovaquone and cycloguanil, the active metabolite of proguanil, respectively. We genotyped the parasites and sequenced their mitochondrial genomes. Results On day 0, both travelers had proguanil-resistant genotypes but atovaquone-sensitive cytb sequences. Day of failure samples exhibited mutations in cytb for both travelers. One traveler had the common Y268S mutation, whereas the other traveler had a previously unreported mutation, I258M. The travelers had unrelated parasite genotypes and different mitochondrial genomes. Conclusions Despite the infections likely having been contracted in the same site, there is no evidence that the cases were related. The mutations likely arose independently during the acute infection or treatment. Our results highlight the importance of genotyping parasites and sequencing the full cytb and dhfr genes in AP failures to rule out transmission of AP-resistant strains and identify novel mechanisms of AP resistance.
Collapse
Affiliation(s)
- Mateusz M Plucinski
- Division of Parasitic Diseases and Malaria, Center for Global Health ; Epidemic Intelligence Service , Centers for Disease Control and Prevention , Atlanta, Georgia
| | - Curtis S Huber
- Division of Parasitic Diseases and Malaria, Center for Global Health
| | - Sheila Akinyi
- Division of Parasitic Diseases and Malaria, Center for Global Health
| | | | - Mary Eschete
- Terrebonne General Medical Center, Houma, Louisiana
| | - Katharine Grady
- Division of Parasitic Diseases and Malaria, Center for Global Health
| | | | - Blaine A Mathison
- Division of Parasitic Diseases and Malaria, Center for Global Health
| | | | - Paul M Arguin
- Division of Parasitic Diseases and Malaria, Center for Global Health
| | - John W Barnwell
- Division of Parasitic Diseases and Malaria, Center for Global Health
| |
Collapse
|
46
|
Njoroge M, Njuguna NM, Mutai P, Ongarora DSB, Smith PW, Chibale K. Recent approaches to chemical discovery and development against malaria and the neglected tropical diseases human African trypanosomiasis and schistosomiasis. Chem Rev 2014; 114:11138-63. [PMID: 25014712 DOI: 10.1021/cr500098f] [Citation(s) in RCA: 82] [Impact Index Per Article: 8.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/14/2022]
Affiliation(s)
| | | | | | | | - Paul W Smith
- Novartis Institute for Tropical Diseases , Singapore 138670, Singapore
| | | |
Collapse
|
47
|
Structural analysis of atovaquone-inhibited cytochrome bc1 complex reveals the molecular basis of antimalarial drug action. Nat Commun 2014; 5:4029. [DOI: 10.1038/ncomms5029] [Citation(s) in RCA: 119] [Impact Index Per Article: 11.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/02/2013] [Accepted: 05/02/2014] [Indexed: 11/08/2022] Open
|
48
|
Emergence of resistance to atovaquone-proguanil in malaria parasites: insights from computational modeling and clinical case reports. Antimicrob Agents Chemother 2014; 58:4504-14. [PMID: 24867967 DOI: 10.1128/aac.02550-13] [Citation(s) in RCA: 30] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/06/2023] Open
Abstract
The usefulness of atovaquone-proguanil (AP) as an antimalarial treatment is compromised by the emergence of atovaquone resistance during therapy. However, the origin of the parasite mitochondrial DNA (mtDNA) mutation conferring atovaquone resistance remains elusive. Here, we report a patient-based stochastic model that tracks the intrahost emergence of mutations in the multicopy mtDNA during the first erythrocytic parasite cycles leading to the malaria febrile episode. The effect of mtDNA copy number, mutation rate, mutation cost, and total parasite load on the mutant parasite load per patient was evaluated. Computer simulations showed that almost any infected patient carried, after four to seven erythrocytic cycles, de novo mutant parasites at low frequency, with varied frequencies of parasites carrying varied numbers of mutant mtDNA copies. A large interpatient variability in the size of this mutant reservoir was found; this variability was due to the different parameters tested but also to the relaxed replication and partitioning of mtDNA copies during mitosis. We also report seven clinical cases in which AP-resistant infections were treated by AP. These provided evidence that parasiticidal drug concentrations against AP-resistant parasites were transiently obtained within days after treatment initiation. Altogether, these results suggest that each patient carries new mtDNA mutant parasites that emerge before treatment but are killed by high starting drug concentrations. However, because the size of this mutant reservoir is highly variable from patient to patient, we propose that some patients fail to eliminate all of the mutant parasites, repeatedly producing de novo AP treatment failures.
Collapse
|
49
|
Ross LS, Gamo FJ, Lafuente-Monasterio MJ, Singh OMP, Rowland P, Wiegand RC, Wirth DF. In vitro resistance selections for Plasmodium falciparum dihydroorotate dehydrogenase inhibitors give mutants with multiple point mutations in the drug-binding site and altered growth. J Biol Chem 2014; 289:17980-95. [PMID: 24782313 PMCID: PMC4140291 DOI: 10.1074/jbc.m114.558353] [Citation(s) in RCA: 48] [Impact Index Per Article: 4.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/22/2022] Open
Abstract
Malaria is a preventable and treatable disease; yet half of the world's population lives at risk of infection, and an estimated 660,000 people die of malaria-related causes every year. Rising drug resistance threatens to make malaria untreatable, necessitating both the discovery of new antimalarial agents and the development of strategies to identify and suppress the emergence and spread of drug resistance. We focused on in-development dihydroorotate dehydrogenase (DHODH) inhibitors. Characterizing resistance pathways for antimalarial agents not yet in clinical use will increase our understanding of the potential for resistance. We identified resistance mechanisms of Plasmodium falciparum (Pf) DHODH inhibitors via in vitro resistance selections. We found 11 point mutations in the PfDHODH target. Target gene amplification and unknown mechanisms also contributed to resistance, albeit to a lesser extent. These mutant parasites were often hypersensitive to other PfDHODH inhibitors, which immediately suggested a novel combination therapy approach to preventing resistance. Indeed, a combination of wild-type and mutant-type selective inhibitors led to resistance far less often than either drug alone. The effects of point mutations in PfDHODH were corroborated with purified recombinant wild-type and mutant-type PfDHODH proteins, which showed the same trends in drug response as the cognate cell lines. Comparative growth assays demonstrated that two mutant parasites grew less robustly than their wild-type parent, and the purified protein of those mutants showed a decrease in catalytic efficiency, thereby suggesting a reason for the diminished growth rate. Co-crystallography of PfDHODH with three inhibitors suggested that hydrophobic interactions are important for drug binding and selectivity.
Collapse
Affiliation(s)
- Leila S Ross
- From the Department of Immunology and Infectious Diseases, Harvard School of Public Health, Boston, Massachusetts 02115
| | - Francisco Javier Gamo
- the Tres Cantos Medicines Development Campus, GlaxoSmithKline, 28760 Tres Cantos, Madrid, Spain
| | | | - Onkar M P Singh
- the Computational and Structural Chemistry, GlaxoSmithKline, Stevenage, Hertfordshire SG1 2NY, United Kingdom, and
| | - Paul Rowland
- the Computational and Structural Chemistry, GlaxoSmithKline, Stevenage, Hertfordshire SG1 2NY, United Kingdom, and
| | - Roger C Wiegand
- the Infectious Disease Initiative, Broad Institute, Cambridge, Massachusetts 02142
| | - Dyann F Wirth
- From the Department of Immunology and Infectious Diseases, Harvard School of Public Health, Boston, Massachusetts 02115, the Infectious Disease Initiative, Broad Institute, Cambridge, Massachusetts 02142
| |
Collapse
|
50
|
Targeting the mitochondrial electron transport chain of Plasmodium falciparum: new strategies towards the development of improved antimalarials for the elimination era. Future Med Chem 2014; 5:1573-91. [PMID: 24024949 DOI: 10.4155/fmc.13.121] [Citation(s) in RCA: 47] [Impact Index Per Article: 4.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/17/2022] Open
Abstract
Despite intense efforts, there has not been a truly new antimalarial, possessing a novel mechanism of action, registered for over 10 years. By virtue of a novel mode of action, it is hoped that the global challenge of multidrug-resistant parasites can be overcome, as well as developing drugs that possess prophylaxis and/or transmission-blocking properties, towards an elimination agenda. Many target-based and whole-cell screening drug development programs have been undertaken in recent years and here an overview of specific projects that have focused on targeting the parasite's mitochondrial electron transport chain is presented. Medicinal chemistry activity has largely focused on inhibitors of the parasite cytochrome bc1 Complex (Complex III) including acridinediones, pyridones and quinolone aryl esters, as well as inhibitors of dihydroorotate dehydrogenase that includes triazolopyrimidines and benzimidazoles. Common barriers to progress and opportunities for novel chemistry and potential additional electron transport chain targets are discussed in the context of the target candidate profiles for uncomplicated malaria.
Collapse
|