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Álvarez-Bardón M, Pérez-Pertejo Y, Ordóñez C, Sepúlveda-Crespo D, Carballeira NM, Tekwani BL, Murugesan S, Martinez-Valladares M, García-Estrada C, Reguera RM, Balaña-Fouce R. Screening Marine Natural Products for New Drug Leads against Trypanosomatids and Malaria. Mar Drugs 2020; 18:E187. [PMID: 32244488 PMCID: PMC7230869 DOI: 10.3390/md18040187] [Citation(s) in RCA: 28] [Impact Index Per Article: 7.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/29/2020] [Revised: 03/24/2020] [Accepted: 03/25/2020] [Indexed: 02/06/2023] Open
Abstract
Neglected Tropical Diseases (NTD) represent a serious threat to humans, especially for those living in poor or developing countries. Almost one-sixth of the world population is at risk of suffering from these diseases and many thousands die because of NTDs, to which we should add the sanitary, labor and social issues that hinder the economic development of these countries. Protozoan-borne diseases are responsible for more than one million deaths every year. Visceral leishmaniasis, Chagas disease or sleeping sickness are among the most lethal NTDs. Despite not being considered an NTD by the World Health Organization (WHO), malaria must be added to this sinister group. Malaria, caused by the apicomplexan parasite Plasmodium falciparum, is responsible for thousands of deaths each year. The treatment of this disease has been losing effectiveness year after year. Many of the medicines currently in use are obsolete due to their gradual loss of efficacy, their intrinsic toxicity and the emergence of drug resistance or a lack of adherence to treatment. Therefore, there is an urgent and global need for new drugs. Despite this, the scant interest shown by most of the stakeholders involved in the pharmaceutical industry makes our present therapeutic arsenal scarce, and until recently, the search for new drugs has not been seriously addressed. The sources of new drugs for these and other pathologies include natural products, synthetic molecules or repurposing drugs. The most frequent sources of natural products are microorganisms, e.g., bacteria, fungi, yeasts, algae and plants, which are able to synthesize many drugs that are currently in use (e.g. antimicrobials, antitumor, immunosuppressants, etc.). The marine environment is another well-established source of bioactive natural products, with recent applications against parasites, bacteria and other pathogens which affect humans and animals. Drug discovery techniques have rapidly advanced since the beginning of the millennium. The combination of novel techniques that include the genetic modification of pathogens, bioimaging and robotics has given rise to the standardization of High-Performance Screening platforms in the discovery of drugs. These advancements have accelerated the discovery of new chemical entities with antiparasitic effects. This review presents critical updates regarding the use of High-Throughput Screening (HTS) in the discovery of drugs for NTDs transmitted by protozoa, including malaria, and its application in the discovery of new drugs of marine origin.
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Affiliation(s)
- María Álvarez-Bardón
- Department of Biomedical Sciences; University of León, 24071 León, Spain; (M.Á.-B.); (Y.P.-P.); (C.O.); (D.S.-C.); (R.M.R.)
| | - Yolanda Pérez-Pertejo
- Department of Biomedical Sciences; University of León, 24071 León, Spain; (M.Á.-B.); (Y.P.-P.); (C.O.); (D.S.-C.); (R.M.R.)
| | - César Ordóñez
- Department of Biomedical Sciences; University of León, 24071 León, Spain; (M.Á.-B.); (Y.P.-P.); (C.O.); (D.S.-C.); (R.M.R.)
| | - Daniel Sepúlveda-Crespo
- Department of Biomedical Sciences; University of León, 24071 León, Spain; (M.Á.-B.); (Y.P.-P.); (C.O.); (D.S.-C.); (R.M.R.)
| | - Nestor M. Carballeira
- Department of Chemistry, University of Puerto Rico, Río Piedras 00925-2537, San Juan, Puerto Rico;
| | - Babu L. Tekwani
- Department of Infectious Diseases, Division of Drug Discovery, Southern Research, Birmingham, AL 35205, USA;
| | - Sankaranarayanan Murugesan
- Department of Pharmacy, Birla Institute of Technology and Science, Pilani Campus, Vidya Vihar, Pilani 333031, India;
| | - Maria Martinez-Valladares
- Department of Animal Health, Instituto de Ganadería de Montaña (CSIC-Universidad de León), Grulleros, 24346 León, Spain;
| | - Carlos García-Estrada
- INBIOTEC (Instituto de Biotecnología de León), Avda. Real 1-Parque Científico de León, 24006 León, Spain;
| | - Rosa M. Reguera
- Department of Biomedical Sciences; University of León, 24071 León, Spain; (M.Á.-B.); (Y.P.-P.); (C.O.); (D.S.-C.); (R.M.R.)
| | - Rafael Balaña-Fouce
- Department of Biomedical Sciences; University of León, 24071 León, Spain; (M.Á.-B.); (Y.P.-P.); (C.O.); (D.S.-C.); (R.M.R.)
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Fenta M, Kahaliw W. Evaluation of Antimalarial Activity of Hydromethanolic Crude Extract and Solvent Fractions of the Leaves of Nuxia congesta R. Br. Ex Fresen ( Buddlejaceae) in Plasmodium berghei Infected Mice. J Exp Pharmacol 2019; 11:121-134. [PMID: 31908546 PMCID: PMC6926096 DOI: 10.2147/jep.s230636] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/11/2019] [Accepted: 11/27/2019] [Indexed: 11/23/2022] Open
Abstract
BACKGROUND In Ethiopia, malaria control has been complicated due to resistance of the parasite and its vectors to the current drugs. Therefore, new drugs are required to avert the problem posed by drug-resistant Plasmodium strains. There is need to investigate alternative sources of antimalarial agents and plants are potential source of antimalarial drugs. This study aimed to investigate the antimalarial activity of the leaves of N. congesta crude extract (hydromethanolic extract) and solvent fractions (n-hexane, chloroform, and aqueous fractions of crude extract) traditionally used to treat malaria in many parts of Ethiopia. METHODS Acute oral toxicity of the leaves of N. congesta extract was assessed in mice up to a dose of 5,000 mg/kg body weight. Antiplasmodial activities of crude extract and solvent fractions were assessed in P. berghei infected female Swiss albino mice models using the Peter's 4-day suppressive test. The curative activities of crude extract and fractions were evaluated using Rane's test. RESULTS Plant extract exhibited no signs of toxicity on mice at a dose of 5,000 mg/kg body weight. Crude extract showed significant parasitemia suppressions at doses of 500 mg/kg (P<0.05), 750 mg/kg (P<0.01), and 1,000 mg/kg (P<0.001) as compared to negative control in the Peter's 4-day suppressive test, but failed to reach a significant level at 500 mg/kg and 750 mg/kg in the curative test (Rane's test). Aqueous fraction showed significant parasitemia suppression at a dose of 400 mg/kg (P<0.05) in curative test and 600 mg/kg (P<0.05) in Peter's 4-day suppressive and curative tests. Maximum suppressive effects of extract (58.13%) and aqueous fraction (44.9%) were observed at the highest doses administered. CONCLUSION Hydromethanolic leaf extract of N. congesta and its aqueous fraction exhibited antimalarial activities. The antimalarial activity and lack of acute toxicity are suggested to uphold the earlier claims made by the Ethiopian traditional practitioners.
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Affiliation(s)
- Melshew Fenta
- University of Gondar Specialized Referral Teaching Hospital, University of Gondar, Gondar, Ethiopia
| | - Wubayehu Kahaliw
- Department of Pharmacology, School of Pharmacy, College of Medicine and Health Sciences, University of Gondar, Gondar, Ethiopia
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Current Screening Methodologies in Drug Discovery for Selected Human Diseases. Mar Drugs 2018; 16:md16080279. [PMID: 30110923 PMCID: PMC6117650 DOI: 10.3390/md16080279] [Citation(s) in RCA: 49] [Impact Index Per Article: 8.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/07/2018] [Accepted: 08/11/2018] [Indexed: 01/31/2023] Open
Abstract
The increase of many deadly diseases like infections by multidrug-resistant bacteria implies re-inventing the wheel on drug discovery. A better comprehension of the metabolisms and regulation of diseases, the increase in knowledge based on the study of disease-born microorganisms’ genomes, the development of more representative disease models and improvement of techniques, technologies, and computation applied to biology are advances that will foster drug discovery in upcoming years. In this paper, several aspects of current methodologies for drug discovery of antibacterial and antifungals, anti-tropical diseases, antibiofilm and antiquorum sensing, anticancer and neuroprotectors are considered. For drug discovery, two different complementary approaches can be applied: classical pharmacology, also known as phenotypic drug discovery, which is the historical basis of drug discovery, and reverse pharmacology, also designated target-based drug discovery. Screening methods based on phenotypic drug discovery have been used to discover new natural products mainly from terrestrial origin. Examples of the discovery of marine natural products are provided. A section on future trends provides a comprehensive overview on recent advances that will foster the pharmaceutical industry.
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Berry SL, Hameed H, Thomason A, Maciej-Hulme ML, Saif Abou-Akkada S, Horrocks P, Price HP. Development of NanoLuc-PEST expressing Leishmania mexicana as a new drug discovery tool for axenic- and intramacrophage-based assays. PLoS Negl Trop Dis 2018; 12:e0006639. [PMID: 30001317 PMCID: PMC6057649 DOI: 10.1371/journal.pntd.0006639] [Citation(s) in RCA: 17] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/09/2018] [Revised: 07/24/2018] [Accepted: 06/26/2018] [Indexed: 12/12/2022] Open
Abstract
The protozoan parasite Leishmania causes leishmaniasis; a spectrum of diseases of which there are an estimated 1 million new cases each year. Current treatments are toxic, expensive, difficult to administer, and resistance to them is emerging. New therapeutics are urgently needed, however, screening the infective amastigote form of the parasite is challenging. Only certain species can be differentiated into axenic amastigotes, and compound activity against these does not always correlate with efficacy against the parasite in its intracellular niche. Methods used to assess compound efficacy on intracellular amastigotes often rely on microscopy-based assays. These are laborious, require specialist equipment and can only determine parasite burden, not parasite viability. We have addressed this clear need in the anti-leishmanial drug discovery process by producing a transgenic L. mexicana cell line that expresses the luciferase NanoLuc-PEST. We tested the sensitivity and versatility of this transgenic strain, in comparison with strains expressing NanoLuc and the red-shifted firefly luciferase. We then compared the NanoLuc-PEST luciferase to the current methods in both axenic and intramacrophage amastigotes following treatment with a supralethal dose of Amphotericin B. NanoLuc-PEST was a more dynamic indicator of cell viability due to its high turnover rate and high signal:background ratio. This, coupled with its sensitivity in the intramacrophage assay, led us to validate the NanoLuc-PEST expressing cell line using the MMV Pathogen Box in a two-step process: i) identify hits against axenic amastigotes, ii) screen these hits using our bioluminescence-based intramacrophage assay. The data obtained from this highlights the potential of compounds active against M. tuberculosis to be re-purposed for use against Leishmania. Our transgenic L. mexicana cell line is therefore a highly sensitive and dynamic system suitable for Leishmania drug discovery in axenic and intramacrophage amastigote models. The protozoan parasite Leishmania causes a spectrum of diseases collectively known as leishmaniasis. The parasite is transmitted to humans by the bite of its vector, the sand fly, following which the parasite invades host white blood cells, particularly macrophages. Leishmaniasis is classified as a neglected tropical disease, and is endemic in 97 countries. Symptoms of the disease depend on the species of Leishmania. These include skin lesions, destruction of the mucosal membranes, and the visceral form which is usually fatal if untreated. Current therapeutic options for leishmaniasis have a number of associated problems that include toxicity, the development of drug resistance and poor patient compliance due to lengthy and painful treatment regimens. New therapeutics are therefore urgently needed. The ability to screen potential drug candidates requires robust screening assays. Currently, screening the intracellular parasite relies on microscopy-based techniques that require expensive equipment, are time consuming and only detect parasite burden, not viability. By using a transgenic cell line that expresses the NanoLuc-PEST luciferase, we show that we have a parasite-specific viability marker that can be used to measure the efficacy of compounds against the intracellular parasite. We validate the potential of this cell line by screening the MMV Pathogen Box.
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Affiliation(s)
- Sarah L. Berry
- Centre for Applied Entomology and Parasitology, School of Life Sciences, Keele University, Newcastle-under-Lyme, Staffordshire, United Kingdom
| | - Hamza Hameed
- Institute for Science and Technology in Medicine, Keele University, Newcastle-under-Lyme, Staffordshire, United Kingdom
| | - Anna Thomason
- Centre for Applied Entomology and Parasitology, School of Life Sciences, Keele University, Newcastle-under-Lyme, Staffordshire, United Kingdom
- Current address: School of Environment and Life Sciences, University of Salford, Salford, United Kingdom
| | - Marissa L. Maciej-Hulme
- Radboud University Medical Center, Department of Nephrology, Geert Grooteplein 10, GA Nijmegan, The Netherlands
| | - Somaia Saif Abou-Akkada
- Centre for Applied Entomology and Parasitology, School of Life Sciences, Keele University, Newcastle-under-Lyme, Staffordshire, United Kingdom
- Faculty of Veterinary Medicine, Alexandria University, Alexandria, Egypt
| | - Paul Horrocks
- Centre for Applied Entomology and Parasitology, School of Life Sciences, Keele University, Newcastle-under-Lyme, Staffordshire, United Kingdom
- Institute for Science and Technology in Medicine, Keele University, Newcastle-under-Lyme, Staffordshire, United Kingdom
| | - Helen P. Price
- Centre for Applied Entomology and Parasitology, School of Life Sciences, Keele University, Newcastle-under-Lyme, Staffordshire, United Kingdom
- * E-mail:
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Branchini BR, Southworth TL. A Highly Sensitive Biosensor for ATP Using a Chimeric Firefly Luciferase. Methods Enzymol 2017; 589:351-364. [PMID: 28336069 DOI: 10.1016/bs.mie.2017.01.004] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/06/2023]
Abstract
Firefly luciferases, which emit visible light in a highly specific ATP-dependent process, have been adapted for a variety of applications based on the detection of the enzymes or using the proteins to measure ATP levels. Based on studies of chimeric luciferases, we engineered a novel luciferase called PLG2 that has enhanced specific activity, and thermal and pH stability compared to the commonly used Photinus pyralis luciferase. We present here protocols for preparing a single assay mixture containing PLG2 that can be used to readily detect femtomole levels of ATP. Our methodology can be used with a variety of samples, including human and bacterial cells, where measurements of ATP can be used as a biosensor for the detection of viable cells.
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D'Alessandro S, Camarda G, Corbett Y, Siciliano G, Parapini S, Cevenini L, Michelini E, Roda A, Leroy D, Taramelli D, Alano P. A chemical susceptibility profile of the Plasmodium falciparum transmission stages by complementary cell-based gametocyte assays. J Antimicrob Chemother 2016; 71:1148-58. [PMID: 26888912 DOI: 10.1093/jac/dkv493] [Citation(s) in RCA: 34] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/29/2015] [Accepted: 12/19/2015] [Indexed: 01/02/2023] Open
Abstract
OBJECTIVES As most available antimalarial drugs are ineffective against the Plasmodium falciparum transmission stages, new drugs against the parasite's gametocytes are urgently needed to combat malaria globally. The unique biology of gametocytes requires assays that need to be specific, to faithfully monitor anti-gametocyte activity, and to be easy to perform, cheap and scalable to high-throughput screening (HTS). METHODS We developed an HTS cell-based assay with P. falciparum gametocytes specifically expressing a potent luciferase. To confirm HTS hit activity for several parasite genotypes, the luciferase assay and the gametocyte lactate dehydrogenase (LDH) assay, usable on any parasite isolate, were compared by screening antimalarial drugs and determining IC50 values of anti-gametocyte hits from the 'Malaria Box' against early- and late-stage gametocytes. RESULTS Comparison of the two assays, conducted on the early and on late gametocyte stages, revealed an excellent correlation (R(2) > 0.9) for the IC50 values obtained by the respective readouts. Differences in susceptibility to drugs and compounds between the two parasite developmental stages were consistently measured in both assays. CONCLUSIONS This work indicates that the luciferase and gametocyte LDH assays are interchangeable and that their specific advantages can be exploited to design an HTS pipeline leading to new transmission-blocking compounds. Results from these assays consistently defined a gametocyte chemical susceptibility profile, relevant to the planning of future drug discovery strategies.
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Affiliation(s)
- Sarah D'Alessandro
- Dipartimento di Scienze Farmacologiche e Biomolecolari, Università degli Studi di Milano, Milano, Italy
| | - Grazia Camarda
- Dipartimento di Malattie Infettive, Parassitarie, Immunomediate, Istituto Superiore di Sanità, Rome, Italy
| | - Yolanda Corbett
- Dipartimento di Scienze Farmacologiche e Biomolecolari, Università degli Studi di Milano, Milano, Italy
| | - Giulia Siciliano
- Dipartimento di Malattie Infettive, Parassitarie, Immunomediate, Istituto Superiore di Sanità, Rome, Italy
| | - Silvia Parapini
- Dipartimento di Scienze Farmacologiche e Biomolecolari, Università degli Studi di Milano, Milano, Italy
| | - Luca Cevenini
- Dipartimento di Chimica 'G. Ciamician', Università di Bologna, Bologna, Italy
| | - Elisa Michelini
- Dipartimento di Chimica 'G. Ciamician', Università di Bologna, Bologna, Italy Istituto Nazionale Biostrutture e Biosistemi (INBB), Roma, Italy
| | - Aldo Roda
- Dipartimento di Chimica 'G. Ciamician', Università di Bologna, Bologna, Italy Istituto Nazionale Biostrutture e Biosistemi (INBB), Roma, Italy
| | - Didier Leroy
- Medicines for Malaria Venture, Geneva, Switzerland
| | - Donatella Taramelli
- Dipartimento di Scienze Farmacologiche e Biomolecolari, Università degli Studi di Milano, Milano, Italy
| | - Pietro Alano
- Dipartimento di Malattie Infettive, Parassitarie, Immunomediate, Istituto Superiore di Sanità, Rome, Italy
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Pérez-Moreno G, Cantizani J, Sánchez-Carrasco P, Ruiz-Pérez LM, Martín J, el Aouad N, Pérez-Victoria I, Tormo JR, González-Menendez V, González I, de Pedro N, Reyes F, Genilloud O, Vicente F, González-Pacanowska D. Discovery of New Compounds Active against Plasmodium falciparum by High Throughput Screening of Microbial Natural Products. PLoS One 2016; 11:e0145812. [PMID: 26735308 PMCID: PMC4703298 DOI: 10.1371/journal.pone.0145812] [Citation(s) in RCA: 26] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/12/2015] [Accepted: 12/09/2015] [Indexed: 12/03/2022] Open
Abstract
Due to the low structural diversity within the set of antimalarial drugs currently available in the clinic and the increasing number of cases of resistance, there is an urgent need to find new compounds with novel modes of action to treat the disease. Microbial natural products are characterized by their large diversity provided in terms of the chemical complexity of the compounds and the novelty of structures. Microbial natural products extracts have been underexplored in the search for new antiparasitic drugs and even more so in the discovery of new antimalarials. Our objective was to find new druggable natural products with antimalarial properties from the MEDINA natural products collection, one of the largest natural product libraries harboring more than 130,000 microbial extracts. In this work, we describe the optimization process and the results of a phenotypic high throughput screen (HTS) based on measurements of Plasmodium lactate dehydrogenase. A subset of more than 20,000 extracts from the MEDINA microbial products collection has been explored, leading to the discovery of 3 new compounds with antimalarial activity. In addition, we report on the novel antiplasmodial activity of 4 previously described natural products.
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Affiliation(s)
- Guiomar Pérez-Moreno
- Instituto de Parasitología y Biomedicina “López-Neyra”, Consejo Superior de Investigaciones Científicas, Parque Tecnológico de Ciencias de la Salud, Avenida del Conocimiento, s/n, 18016-Armilla (Granada), Spain
| | - Juan Cantizani
- Fundación MEDINA, Parque Tecnológico de Ciencias de la Salud, Avenida del Conocimiento, 34.18016-Armilla (Granada), Spain
| | - Paula Sánchez-Carrasco
- Instituto de Parasitología y Biomedicina “López-Neyra”, Consejo Superior de Investigaciones Científicas, Parque Tecnológico de Ciencias de la Salud, Avenida del Conocimiento, s/n, 18016-Armilla (Granada), Spain
| | - Luis Miguel Ruiz-Pérez
- Instituto de Parasitología y Biomedicina “López-Neyra”, Consejo Superior de Investigaciones Científicas, Parque Tecnológico de Ciencias de la Salud, Avenida del Conocimiento, s/n, 18016-Armilla (Granada), Spain
| | - Jesús Martín
- Fundación MEDINA, Parque Tecnológico de Ciencias de la Salud, Avenida del Conocimiento, 34.18016-Armilla (Granada), Spain
| | - Noureddine el Aouad
- Fundación MEDINA, Parque Tecnológico de Ciencias de la Salud, Avenida del Conocimiento, 34.18016-Armilla (Granada), Spain
| | - Ignacio Pérez-Victoria
- Fundación MEDINA, Parque Tecnológico de Ciencias de la Salud, Avenida del Conocimiento, 34.18016-Armilla (Granada), Spain
| | - José Rubén Tormo
- Fundación MEDINA, Parque Tecnológico de Ciencias de la Salud, Avenida del Conocimiento, 34.18016-Armilla (Granada), Spain
| | - Víctor González-Menendez
- Fundación MEDINA, Parque Tecnológico de Ciencias de la Salud, Avenida del Conocimiento, 34.18016-Armilla (Granada), Spain
| | - Ignacio González
- Fundación MEDINA, Parque Tecnológico de Ciencias de la Salud, Avenida del Conocimiento, 34.18016-Armilla (Granada), Spain
| | - Nuria de Pedro
- Fundación MEDINA, Parque Tecnológico de Ciencias de la Salud, Avenida del Conocimiento, 34.18016-Armilla (Granada), Spain
| | - Fernando Reyes
- Fundación MEDINA, Parque Tecnológico de Ciencias de la Salud, Avenida del Conocimiento, 34.18016-Armilla (Granada), Spain
| | - Olga Genilloud
- Fundación MEDINA, Parque Tecnológico de Ciencias de la Salud, Avenida del Conocimiento, 34.18016-Armilla (Granada), Spain
| | - Francisca Vicente
- Fundación MEDINA, Parque Tecnológico de Ciencias de la Salud, Avenida del Conocimiento, 34.18016-Armilla (Granada), Spain
| | - Dolores González-Pacanowska
- Instituto de Parasitología y Biomedicina “López-Neyra”, Consejo Superior de Investigaciones Científicas, Parque Tecnológico de Ciencias de la Salud, Avenida del Conocimiento, s/n, 18016-Armilla (Granada), Spain
- * E-mail:
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8
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Branchini BR, Southworth TL, Fontaine DM, Kohrt D, Talukder M, Michelini E, Cevenini L, Roda A, Grossel MJ. An enhanced chimeric firefly luciferase-inspired enzyme for ATP detection and bioluminescence reporter and imaging applications. Anal Biochem 2015; 484:148-53. [PMID: 26049097 PMCID: PMC4496250 DOI: 10.1016/j.ab.2015.05.020] [Citation(s) in RCA: 37] [Impact Index Per Article: 4.1] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/31/2015] [Revised: 05/26/2015] [Accepted: 05/29/2015] [Indexed: 10/23/2022]
Abstract
Firefly luciferases, which emit visible light in a highly specific ATP-dependent process, have been adapted for a variety of applications, including gene reporter assays, whole-cell biosensor measurements, and in vivo imaging. We previously reported the approximately 2-fold enhanced activity and 1.4-fold greater bioluminescence quantum yield properties of a chimeric enzyme that contains the N-domain of Photinus pyralis luciferase joined to the C-domain of Luciola italica luciferase. Subsequently, we identified 5 amino acid changes based on L. italica that are the main determinants of the improved bioluminescence properties. Further engineering to enhance thermal and pH stability produced a novel luciferase called PLG2. We present here a systematic comparison of the spectral and physical properties of the new protein with P. pyralis luciferase and demonstrate the potential of PLG2 for use in assays based on the detection of femtomole levels of ATP. In addition, we compared the performance of a mammalian codon-optimized version of the cDNA for PLG2 with the luc2 gene in HEK293T cells. Using an optimized low-cost assay system, PLG2 activity can be monitored in mammalian cell lysates and living cells with 4.4-fold and approximately 3.0-fold greater sensitivity, respectively. PLG2 could be an improved alternative to Promega's luc2 for reporter and imaging applications.
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Affiliation(s)
- Bruce R Branchini
- Department of Chemistry, Connecticut College, New London, CT 06320, USA.
| | - Tara L Southworth
- Department of Chemistry, Connecticut College, New London, CT 06320, USA
| | | | - Dawn Kohrt
- Department of Biology, Connecticut College, New London, CT 06320, USA
| | - Munya Talukder
- Department of Chemistry, Connecticut College, New London, CT 06320, USA
| | - Elisa Michelini
- Department of Chemistry "G. Ciamician", University of Bologna, 40126 Bologna, Italy
| | - Luca Cevenini
- Department of Chemistry "G. Ciamician", University of Bologna, 40126 Bologna, Italy
| | - Aldo Roda
- Department of Chemistry "G. Ciamician", University of Bologna, 40126 Bologna, Italy
| | - Martha J Grossel
- Department of Biology, Connecticut College, New London, CT 06320, USA
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9
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Mongui A, Pérez-Llanos FJ, Yamamoto MM, Lozano M, Zambrano MM, Del Portillo P, Fernández-Becerra C, Restrepo S, Del Portillo HA, Junca H. Development of a genetic tool for functional screening of anti-malarial bioactive extracts in metagenomic libraries. Malar J 2015; 14:233. [PMID: 26040274 PMCID: PMC4464701 DOI: 10.1186/s12936-015-0748-6] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/17/2014] [Accepted: 05/26/2015] [Indexed: 12/25/2022] Open
Abstract
Background The chemical treatment of Plasmodium falciparum for human infections is losing efficacy each year due to the rise of resistance. One possible strategy to find novel anti-malarial drugs is to access the largest reservoir of genomic biodiversity source on earth present in metagenomes of environmental microbial communities. Methods A bioluminescent P. falciparum parasite was used to quickly detect shifts in viability of microcultures grown in 96-well plates. A synthetic gene encoding the Dermaseptin 4 peptide was designed and cloned under tight transcriptional control in a large metagenomic insert context (30 kb) to serve as proof-of-principle for the screening platform. Results Decrease in parasite viability consistently correlated with bioluminescence emitted from parasite microcultures, after their exposure to bacterial extracts containing a plasmid or fosmid engineered to encode the Dermaseptin 4 anti-malarial peptide. Conclusions Here, a new technical platform to access the anti-malarial potential in microbial environmental metagenomes has been developed.
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Affiliation(s)
- Alvaro Mongui
- RG Microbial Ecology: Metabolism, Genomics & Evolution - CorpoGen, Bogotá, Colombia. .,Department of Biological Sciences, Universidad de los Andes, Bogotá, Colombia.
| | - Francy J Pérez-Llanos
- RG Microbial Ecology: Metabolism, Genomics & Evolution - CorpoGen, Bogotá, Colombia. .,Department of Biological Sciences, Universidad de los Andes, Bogotá, Colombia.
| | - Marcio M Yamamoto
- Departamento de Parasitologia, Universidade de São Paulo, São Paulo, Brazil.
| | - Marcela Lozano
- RG Microbial Ecology: Metabolism, Genomics & Evolution - CorpoGen, Bogotá, Colombia.
| | - Maria M Zambrano
- RG Microbial Ecology: Metabolism, Genomics & Evolution - CorpoGen, Bogotá, Colombia.
| | - Patricia Del Portillo
- RG Microbial Ecology: Metabolism, Genomics & Evolution - CorpoGen, Bogotá, Colombia.
| | - Carmen Fernández-Becerra
- ICREA at ISGlobal, Barcelona Ctr Int Health Res (CRESIB), Hospital Clínic - Universitat de Barcelona, Barcelona, Spain.
| | - Silvia Restrepo
- Department of Biological Sciences, Universidad de los Andes, Bogotá, Colombia.
| | - Hernando A Del Portillo
- ICREA at ISGlobal, Barcelona Ctr Int Health Res (CRESIB), Hospital Clínic - Universitat de Barcelona, Barcelona, Spain. .,Institució Catalana de Recerca I Estudis Avançats (ICREA), Barcelona, Spain.
| | - Howard Junca
- RG Microbial Ecology: Metabolism, Genomics & Evolution - CorpoGen, Bogotá, Colombia. .,Present Address: Applied Biology Program, Faculty of Basic & Applied Sciences, Universidad Militar Nueva Granada-UMNG, Campus Cajicá, Bogotá, DC, Colombia.
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Siciliano G, Alano P. Enlightening the malaria parasite life cycle: bioluminescent Plasmodium in fundamental and applied research. Front Microbiol 2015; 6:391. [PMID: 26029172 PMCID: PMC4426725 DOI: 10.3389/fmicb.2015.00391] [Citation(s) in RCA: 32] [Impact Index Per Article: 3.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/20/2015] [Accepted: 04/16/2015] [Indexed: 12/31/2022] Open
Abstract
The unicellular protozoan parasites of the genus Plasmodium impose on human health worldwide the enormous burden of malaria. The possibility to genetically modify several species of malaria parasites represented a major advance in the possibility to elucidate their biology and is now turning laboratory lines of transgenic Plasmodium into precious weapons to fight malaria. Amongst the various genetically modified plasmodia, transgenic parasite lines expressing bioluminescent reporters have been essential to unveil mechanisms of parasite gene expression and to develop in vivo imaging approaches in mouse malaria models. Mainly the human malaria parasite Plasmodium falciparum and the rodent parasite P. berghei have been engineered to express bioluminescent reporters in almost all the developmental stages of the parasite along its complex life cycle between the insect and the vertebrate hosts. Plasmodium lines expressing conventional and improved luciferase reporters are now gaining a central role to develop cell based assays in the much needed search of new antimalarial drugs and to open innovative approaches for both fundamental and applied research in malaria.
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Affiliation(s)
| | - Pietro Alano
- Dipartimento di Malattie Infettive, Parassitarie ed Immunomediate, Istituto Superiore di SanitàRome, Italy
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11
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Plasmodium falciparum transfected with ultra bright NanoLuc luciferase offers high sensitivity detection for the screening of growth and cellular trafficking inhibitors. PLoS One 2014; 9:e112571. [PMID: 25392998 PMCID: PMC4231029 DOI: 10.1371/journal.pone.0112571] [Citation(s) in RCA: 49] [Impact Index Per Article: 4.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/05/2014] [Accepted: 10/08/2014] [Indexed: 11/19/2022] Open
Abstract
Drug discovery is a key part of malaria control and eradication strategies, and could benefit from sensitive and affordable assays to quantify parasite growth and to help identify the targets of potential anti-malarial compounds. Bioluminescence, achieved through expression of exogenous luciferases, is a powerful tool that has been applied in studies of several aspects of parasite biology and high throughput growth assays. We have expressed the new reporter NanoLuc (Nluc) luciferase in Plasmodium falciparum and showed it is at least 100 times brighter than the commonly used firefly luciferase. Nluc brightness was explored as a means to achieve a growth assay with higher sensitivity and lower cost. In addition we attempted to develop other screening assays that may help interrogate libraries of inhibitory compounds for their mechanism of action. To this end parasites were engineered to express Nluc in the cytoplasm, the parasitophorous vacuole that surrounds the intraerythrocytic parasite or exported to the red blood cell cytosol. As proof-of-concept, these parasites were used to develop functional screening assays for quantifying the effects of Brefeldin A, an inhibitor of protein secretion, and Furosemide, an inhibitor of new permeation pathways used by parasites to acquire plasma nutrients.
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12
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Herman Lara H. Luciferase Time-based, High-throughput Screening Assay for the Discovery of HIV-1 Inhibitors. ACTA ACUST UNITED AC 2014. [DOI: 10.15406/jhvrv.2014.01.00017] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022]
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13
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Cevenini L, Camarda G, Michelini E, Siciliano G, Calabretta MM, Bona R, Kumar TRS, Cara A, Branchini BR, Fidock DA, Roda A, Alano P. Multicolor bioluminescence boosts malaria research: quantitative dual-color assay and single-cell imaging in Plasmodium falciparum parasites. Anal Chem 2014; 86:8814-21. [PMID: 25102353 PMCID: PMC4151787 DOI: 10.1021/ac502098w] [Citation(s) in RCA: 49] [Impact Index Per Article: 4.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/06/2023]
Abstract
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New
reliable and cost-effective antimalarial drug screening assays
are urgently needed to identify drugs acting on different stages of
the parasite Plasmodium falciparum,
and particularly those responsible for human-to-mosquito transmission,
that is, the P. falciparum gametocytes.
Low Z′ factors, narrow dynamic ranges, and/or
extended assay times are commonly reported in current gametocyte assays
measuring gametocyte-expressed fluorescent or luciferase reporters,
endogenous ATP levels, activity of gametocyte enzymes, or redox-dependent
dye fluorescence. We hereby report on a dual-luciferase gametocyte
assay with immature and mature P. falciparum gametocyte stages expressing red and green-emitting luciferases
from Pyrophorus plagiophthalamus under
the control of the parasite sexual stage-specific pfs16 gene promoter. The assay was validated with reference antimalarial
drugs and allowed to quantitatively and simultaneously measure stage-specific
drug effects on parasites at different developmental stages. The optimized
assay, requiring only 48 h incubation with drugs and using a cost-effective
luminogenic substrate, significantly reduces assay cost and time in
comparison to state-of-the-art analogous assays. The assay had a Z′ factor of 0.71 ± 0.03, and it is suitable
for implementation in 96- and 384-well microplate formats. Moreover,
the use of a nonlysing d-luciferin substrate significantly
improved the reliability of the assay and allowed one to perform,
for the first time, P. falciparum bioluminescence
imaging at single-cell level.
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Affiliation(s)
- Luca Cevenini
- INBB, Istituto Nazionale di Biostrutture e Biosistemi , 00136 Rome, Italy
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Identification of MMV malaria box inhibitors of plasmodium falciparum early-stage gametocytes using a luciferase-based high-throughput assay. Antimicrob Agents Chemother 2013; 57:6050-62. [PMID: 24060871 DOI: 10.1128/aac.00870-13] [Citation(s) in RCA: 84] [Impact Index Per Article: 7.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022] Open
Abstract
The design of new antimalarial combinations to treat Plasmodium falciparum infections requires drugs that, in addition to resolving disease symptoms caused by asexual blood stage parasites, can also interrupt transmission to the mosquito vector. Gametocytes, which are essential for transmission, develop as sexual blood stage parasites in the human host over 8 to 12 days and are the most accessible developmental stage for transmission-blocking drugs. Considerable effort is currently being devoted to identifying compounds active against mature gametocytes. However, investigations on the drug sensitivity of developing gametocytes, as well as screening methods for identifying inhibitors of early gametocytogenesis, remain scarce. We have developed a luciferase-based high-throughput screening (HTS) assay using tightly synchronous stage I to III gametocytes from a recombinant P. falciparum line expressing green fluorescent protein (GFP)-luciferase. The assay has been used to evaluate the early-stage gametocytocidal activity of the MMV Malaria Box, a collection of 400 compounds with known antimalarial (asexual blood stage) activity. Screening this collection against early-stage (I to III) gametocytes yielded 64 gametocytocidal compounds with 50% inhibitory concentrations (IC50s) below 2.5 μM. This assay is reproducible and suitable for the screening of large compound libraries, with an average percent coefficient of variance (%CV) of ≤5%, an average signal-to-noise ratio (S:N) of >30, and a Z' of ∼0.8. Our findings highlight the need for screening efforts directed specifically against early gametocytogenesis and indicate the importance of experimental verification of early-stage gametocytocidal activity in the development of new antimalarial candidates for combination therapy.
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15
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Sykes ML, Avery VM. Approaches to Protozoan Drug Discovery: Phenotypic Screening. J Med Chem 2013; 56:7727-40. [DOI: 10.1021/jm4004279] [Citation(s) in RCA: 63] [Impact Index Per Article: 5.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Affiliation(s)
- Melissa L. Sykes
- Discovery Biology, Eskitis Institute
for Drug Discovery, Griffith University, Nathan, Queensland, Australia
| | - Vicky M. Avery
- Discovery Biology, Eskitis Institute
for Drug Discovery, Griffith University, Nathan, Queensland, Australia
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16
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Pohlit AM, Lima RBS, Frausin G, Silva LFRE, Lopes SCP, Moraes CB, Cravo P, Lacerda MVG, Siqueira AM, Freitas-Junior LH, Costa FTM. Amazonian plant natural products: perspectives for discovery of new antimalarial drug leads. Molecules 2013; 18:9219-40. [PMID: 23917112 PMCID: PMC6270278 DOI: 10.3390/molecules18089219] [Citation(s) in RCA: 25] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/02/2013] [Revised: 07/14/2013] [Accepted: 07/18/2013] [Indexed: 02/07/2023] Open
Abstract
Plasmodium falciparum and P. vivax malaria parasites are now resistant, or showing signs of resistance, to most drugs used in therapy. Novel chemical entities that exhibit new mechanisms of antiplasmodial action are needed. New antimalarials that block transmission of Plasmodium spp. from humans to Anopheles mosquito vectors are key to malaria eradication efforts. Although P. vivax causes a considerable number of malaria cases, its importance has for long been neglected. Vivax malaria can cause severe manifestations and death; hence there is a need for P. vivax-directed research. Plants used in traditional medicine, namely Artemisia annua and Cinchona spp. are the sources of the antimalarial natural products artemisinin and quinine, respectively. Based on these compounds, semi-synthetic artemisinin-derivatives and synthetic quinoline antimalarials have been developed and are the most important drugs in the current therapeutic arsenal for combating malaria. In the Amazon region, where P. vivax predominates, there is a local tradition of using plant-derived preparations to treat malaria. Here, we review the current P. falciparum and P. vivax drug-sensitivity assays, focusing on challenges and perspectives of drug discovery for P. vivax, including tests against hypnozoites. We also present the latest findings of our group and others on the antiplasmodial and antimalarial chemical components from Amazonian plants that may be potential drug leads against malaria.
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Affiliation(s)
- Adrian Martin Pohlit
- Instituto Nacional de Pesquisa da Amazônia (INPA), Av. André Araújo, 2936, 69067-375 Manaus, AM, Brazil; E-Mails: (R.B.S.L.); (G.F.); (L.F.R.S.)
| | - Renata Braga Souza Lima
- Instituto Nacional de Pesquisa da Amazônia (INPA), Av. André Araújo, 2936, 69067-375 Manaus, AM, Brazil; E-Mails: (R.B.S.L.); (G.F.); (L.F.R.S.)
| | - Gina Frausin
- Instituto Nacional de Pesquisa da Amazônia (INPA), Av. André Araújo, 2936, 69067-375 Manaus, AM, Brazil; E-Mails: (R.B.S.L.); (G.F.); (L.F.R.S.)
| | - Luiz Francisco Rocha e Silva
- Instituto Nacional de Pesquisa da Amazônia (INPA), Av. André Araújo, 2936, 69067-375 Manaus, AM, Brazil; E-Mails: (R.B.S.L.); (G.F.); (L.F.R.S.)
| | - Stefanie Costa Pinto Lopes
- Departamento de Genética, Evolução e Bioagentes, Universidade Estadual de Campinas-UNICAMP, P.O. Box 6109, 13083-862 Campinas, SP, Brazil; E-Mail:
| | - Carolina Borsoi Moraes
- Laboratório Nacional de Biociências (LNBio) – Centro Nacional de Pesquisa em Energia e Materiais (CNEPM) - P.O. Box 6192, 13083-970 Campinas, SP, Brazil; E-Mails: (C.B.M.); (L.H.F.-J.)
| | - Pedro Cravo
- Programa de Mestrado em Sociedade, Tecnologia e Meio Ambiente. UniEVANGÉLICA-Centro Universitário de Anápolis, 75083-515 Anapólis, GO, Brazil; E-Mail:
- Centro de Malária e Doenças Tropicais, LA/IHMT-Universidade Nova de Lisboa, 1349-008 Lisboa, Portugal
| | - Marcus Vinícius Guimarães Lacerda
- Fundação de Medicina Tropical Dr. Heitor Vieira Dourado, 69040-000 Manaus, AM, Brazil; E-Mails: (M.V.G.L.); (A.M.S.)
- Programa de Pós-Graduação em Medicina Tropical, Universidade do Estado do Amazonas, 69040-000 Manaus, AM, Brazil
| | - André Machado Siqueira
- Fundação de Medicina Tropical Dr. Heitor Vieira Dourado, 69040-000 Manaus, AM, Brazil; E-Mails: (M.V.G.L.); (A.M.S.)
- Programa de Pós-Graduação em Medicina Tropical, Universidade do Estado do Amazonas, 69040-000 Manaus, AM, Brazil
| | - Lucio H. Freitas-Junior
- Laboratório Nacional de Biociências (LNBio) – Centro Nacional de Pesquisa em Energia e Materiais (CNEPM) - P.O. Box 6192, 13083-970 Campinas, SP, Brazil; E-Mails: (C.B.M.); (L.H.F.-J.)
| | - Fabio Trindade Maranhão Costa
- Departamento de Genética, Evolução e Bioagentes, Universidade Estadual de Campinas-UNICAMP, P.O. Box 6109, 13083-862 Campinas, SP, Brazil; E-Mail:
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Van Reet N, Pyana P, Rogé S, Claes F, Büscher P. Luminescent multiplex viability assay for Trypanosoma brucei gambiense. Parasit Vectors 2013; 6:207. [PMID: 23856321 PMCID: PMC3728213 DOI: 10.1186/1756-3305-6-207] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/23/2013] [Accepted: 07/09/2013] [Indexed: 11/10/2022] Open
Abstract
BACKGROUND New compounds for the treatment of human African trypanosomiasis (HAT) are urgently required. Trypanosoma brucei (T.b.) gambiense is the leading cause of HAT, yet T.b. gambiense is often not the prime target organism in drug discovery. This may be attributed to the difficulties in handling this subspecies and the lack of an efficient viability assay to monitor drug efficacy. METHODS In this study, a T.b. gambiense strain, recently isolated in the D.R. Congo, was made bioluminescent by transfection with Renilla luciferase (RLuc) without altering its in vitro and in vivo growth characteristics. A luminescent multiplex viability assay (LMVA), based on measurement of the Renilla luciferase activity and the ATP content of the cells within the same experiment, was investigated as an alternative to the standard fluorimetric resazurin viability assay for drug sensitivity testing of T.b. gambiense. RESULTS In a 96-well format, the RLuc transfected strain showed a detection limit of 2 × 10(4) cells ml(-1) for the Renilla luciferase measurement and 5 × 10(3) cells ml(-1) for the ATP measurement. Both assays of the LMVA showed linearity up to 10(6) cells ml(-1) and correlated well with the cell density during exponential growth of the long slender bloodstream forms. The LMVA was compared to the fluorimetric resazurin viability assay for drug sensitivity testing of pentamidine, eflornithine, nifurtimox and melarsoprol with both the wild type and the RLuc transfected population. For each drug, the IC50 value of the RLuc population was similar to that of the wild type when determined with either the fluorimetric resazurin method or the LMVA. For eflornithine, nifurtimox and melarsoprol we found no difference between the IC50 values in both viability assays. In contrast, the IC50 value of pentamidine was higher when determined with the fluorimetric resazurin method than in both assays of the LMVA. CONCLUSIONS LMVA has some advantages for viability measurement of T.b. gambiense: it requires less incubation time for viability detection than the fluorimetric resazurin assay and in LMVA, two sensitive and independent viability assays are performed in the same experiment.
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Affiliation(s)
- Nick Van Reet
- Department of Biomedical Sciences, Institute of Tropical Medicine, Antwerp, Belgium.
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Abstract
The discovery of new chemical starting points with the ability to inhibit Plasmodium falciparum sexual stages, and therefore block the disease transmission, is urgently required. These will form the basis for the development of new therapeutic combinations for the treatment and elimination of malaria and the ultimate goal of global eradication. Recent screening of large chemical libraries against the parasite asexual stages has resulted in the public availability of focused subsets of known antimalarial actives, which represent an excellent starting point for the identification of new gametocytocidal compounds. New stage-specific methodologies aimed at increasing the throughput for assessing compound activity against in vitro cultured gametocytes have recently been published. This article discusses the challenges of assay-oriented large-scale gametocyte culturing and reviews the state-of-the art in gametocytocidal assay development and outcomes.
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Hasenkamp S, Sidaway A, Devine O, Roye R, Horrocks P. Evaluation of bioluminescence-based assays of anti-malarial drug activity. Malar J 2013; 12:58. [PMID: 23394077 PMCID: PMC3571881 DOI: 10.1186/1475-2875-12-58] [Citation(s) in RCA: 25] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/27/2012] [Accepted: 02/03/2013] [Indexed: 11/16/2022] Open
Abstract
Background Transgenic Plasmodium falciparum expressing luciferase offers an attractive bioluminescence-based assay platform for the investigation of the pharmacological properties of anti-malarial drugs. Here a side-by-side comparison of bioluminescence and fluorescence-based assays, utilizing a luciferase reporter cassette that confers a strong temporal pattern of luciferase expression during the S-phase of intraerythrocytic development, is reported. Methods Key assay parameters for a range of commercially available luminogenic substrates are determined and compared to those measured using a Malaria Sybr Green I fluorescence assay. In addition, the short-term temporal effects of anti-malarial compounds are evaluated using both bioluminescent and fluorescent assay platforms. Results The Z’, % coefficient of variation and 50% inhibition concentrations are essentially the same for bioluminescent and fluorescent assays in transgenic parasites generated in both chloroquine-sensitive and -resistant genetic backgrounds. Bioluminescent assays, irrespective of the luminogenic agent employed, do, however, offer significantly enhanced signal-to-noise ratios. Moreover, the bioluminescent assay is more dynamic in terms of determining temporal effects immediately following drug perturbation. Conclusion This study suggests that opportunities for bioluminescence-based assays lie not in the measurement of 50% inhibition concentrations, where the cheaper fluorescence assay performs excellently and is not restricted by the need to genetically modify the parasite clone under investigation. Instead, assays that use the dynamic response of the luciferase reporter for semi-automated screening of additional pharmacological properties, such as relative rate-of-kill and lethal dose estimation, are a more attractive development opportunity.
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Affiliation(s)
- Sandra Hasenkamp
- Institute for Science and Technology in Medicine, Keele University, Staffordshire, UK
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Aguiar ACC, Rocha EMMD, Souza NBD, França TCC, Krettli AU. New approaches in antimalarial drug discovery and development: a review. Mem Inst Oswaldo Cruz 2012; 107:831-45. [DOI: 10.1590/s0074-02762012000700001] [Citation(s) in RCA: 49] [Impact Index Per Article: 4.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/01/2012] [Accepted: 08/16/2012] [Indexed: 01/22/2023] Open
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