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De Luca V, Giovannuzzi S, Capasso C, Supuran CT. Cloning, expression, and purification of an α-carbonic anhydrase from Toxoplasma gondii to unveil its kinetic parameters and anion inhibition profile. J Enzyme Inhib Med Chem 2024; 39:2346523. [PMID: 38847581 PMCID: PMC11163988 DOI: 10.1080/14756366.2024.2346523] [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: 02/22/2024] [Accepted: 04/17/2024] [Indexed: 06/12/2024] Open
Abstract
Toxoplasmosis, induced by the intracellular parasite Toxoplasma gondii, holds considerable implications for global health. While treatment options primarily focusing on folate pathway enzymes have notable limitations, current research endeavours concentrate on pinpointing specific metabolic pathways vital for parasite survival. Carbonic anhydrases (CAs, EC 4.2.1.1) have emerged as potential drug targets due to their role in fundamental reactions critical for various protozoan metabolic processes. Within T. gondii, the Carbonic Anhydrase-Related Protein (TgCA_RP) plays a pivotal role in rhoptry biogenesis. Notably, α-CA (TcCA) from another protozoan, Trypanosoma cruzi, exhibited considerable susceptibility to classical CA inhibitors (CAIs) such as anions, sulphonamides, thiols, and hydroxamates. Here, the recombinant DNA technology was employed to synthesise and clone the identified gene in the T. gondii genome, which encodes an α-CA protein (Tg_CA), with the purpose of heterologously overexpressing its corresponding protein. Tg_CA kinetic constants were determined, and its inhibition patterns explored with inorganic metal-complexing compounds, which are relevant for rational compound design. The significance of this study lies in the potential development of innovative therapeutic strategies that disrupt the vital metabolic pathways crucial for T. gondii survival and virulence. This research may lead to the development of targeted treatments, offering new approaches to manage toxoplasmosis.
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Affiliation(s)
- Viviana De Luca
- Department of Biology, Agriculture and Food Sciences, National Research Council (CNR), Institute of Biosciences and Bioresources, Naples, Italy
| | - Simone Giovannuzzi
- Neurofarba Department, Pharmaceutical and Nutraceutical Section, University of Florence, Sesto Fiorentino, Italy
| | - Clemente Capasso
- Department of Biology, Agriculture and Food Sciences, National Research Council (CNR), Institute of Biosciences and Bioresources, Naples, Italy
| | - Claudiu T. Supuran
- Neurofarba Department, Pharmaceutical and Nutraceutical Section, University of Florence, Sesto Fiorentino, Italy
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Hulverson MA, Choi R, Schaefer DA, Betzer DP, McCloskey MC, Whitman GR, Huang W, Lee S, Pranata A, McLeod MD, Marsh KC, Kempf DJ, LeRoy BE, Zafiratos MT, Bielinski AL, Hackman RC, Ojo KK, Arnold SLM, Barrett LK, Tzipori S, Riggs MW, Fan E, Van Voorhis WC. Comparison of Toxicities among Different Bumped Kinase Inhibitor Analogs for Treatment of Cryptosporidiosis. Antimicrob Agents Chemother 2023; 67:e0142522. [PMID: 36920244 PMCID: PMC10112232 DOI: 10.1128/aac.01425-22] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/20/2022] [Accepted: 02/09/2023] [Indexed: 03/16/2023] Open
Abstract
Recent advances on the development of bumped kinase inhibitors for treatment of cryptosporidiosis have focused on the 5-aminopyrazole-4-carboxamide scaffold, due to analogs that have less hERG inhibition, superior efficacy, and strong in vitro safety profiles. Three compounds, BKI-1770, -1841, and -1708, showed strong efficacy in C. parvum infected mice. Both BKI-1770 and BKI-1841 had efficacy in the C. parvum newborn calf model, reducing diarrhea and oocyst excretion. However, both compounds caused hyperflexion of the limbs seen as dropped pasterns. Toxicity experiments in rats and calves dosed with BKI-1770 showed enlargement of the epiphyseal growth plate at doses only slightly higher than the efficacious dose. Mice were used as a screen to check for bone toxicity, by changes to the tibia epiphyseal growth plate, or neurological causes, by use of a locomotor activity box. These results showed neurological effects from both BKI-1770 and BKI-1841 and bone toxicity in mice from BKI-1770, indicating one or both effects may be contributing to toxicity. However, BKI-1708 remains a viable treatment candidate for further evaluation as it showed no signs of bone toxicity or neurological effects in mice.
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Affiliation(s)
- Matthew A. Hulverson
- Department of Medicine, Division of Allergy and Infectious Disease, Center for Emerging and Reemerging Infectious Disease (CERID), University of Washington, Seattle, Washington, USA
| | - Ryan Choi
- Department of Medicine, Division of Allergy and Infectious Disease, Center for Emerging and Reemerging Infectious Disease (CERID), University of Washington, Seattle, Washington, USA
| | - Deborah A. Schaefer
- School of Animal and Comparative Biomedical Sciences, College of Agriculture and Life Sciences, University of Arizona, Tucson, Arizona, USA
| | - Dana P. Betzer
- School of Animal and Comparative Biomedical Sciences, College of Agriculture and Life Sciences, University of Arizona, Tucson, Arizona, USA
| | - Molly C. McCloskey
- Department of Medicine, Division of Allergy and Infectious Disease, Center for Emerging and Reemerging Infectious Disease (CERID), University of Washington, Seattle, Washington, USA
| | - Grant R. Whitman
- Department of Medicine, Division of Allergy and Infectious Disease, Center for Emerging and Reemerging Infectious Disease (CERID), University of Washington, Seattle, Washington, USA
| | - Wenlin Huang
- Department of Biochemistry, University of Washington, Seattle, Washington, USA
| | - Sangun Lee
- Department of Infectious Disease and Global Health, Cummings School of Veterinary Medicine at Tufts University, North Grafton, Massachusetts, USA
| | - Andy Pranata
- Research School of Chemistry, Australian National University, Canberra, ACT, Australia
| | - Malcolm D. McLeod
- Research School of Chemistry, Australian National University, Canberra, ACT, Australia
| | - Kennan C. Marsh
- Research and Development, AbbVie, Inc., North Chicago, Illinois, USA
| | - Dale J. Kempf
- Research and Development, AbbVie, Inc., North Chicago, Illinois, USA
- Former employee of AbbVie, Inc., North Chicago, Illinois, USA
| | - Bruce E. LeRoy
- Research and Development, AbbVie, Inc., North Chicago, Illinois, USA
| | - Mark T. Zafiratos
- Research and Development, AbbVie, Inc., North Chicago, Illinois, USA
| | | | - Robert C. Hackman
- Fred Hutchinson Cancer Research Center, Seattle, Washington, USA
- Department of Pathology, University of Washington, Seattle, Washington, USA
- Department of Laboratory Medicine, University of Washington, Seattle, Washington, USA
| | - Kayode K. Ojo
- Department of Medicine, Division of Allergy and Infectious Disease, Center for Emerging and Reemerging Infectious Disease (CERID), University of Washington, Seattle, Washington, USA
| | - Samuel L. M. Arnold
- Department of Medicine, Division of Allergy and Infectious Disease, Center for Emerging and Reemerging Infectious Disease (CERID), University of Washington, Seattle, Washington, USA
| | - Lynn K. Barrett
- Department of Medicine, Division of Allergy and Infectious Disease, Center for Emerging and Reemerging Infectious Disease (CERID), University of Washington, Seattle, Washington, USA
| | - Saul Tzipori
- Department of Infectious Disease and Global Health, Cummings School of Veterinary Medicine at Tufts University, North Grafton, Massachusetts, USA
| | - Michael W. Riggs
- School of Animal and Comparative Biomedical Sciences, College of Agriculture and Life Sciences, University of Arizona, Tucson, Arizona, USA
| | - Erkang Fan
- Department of Biochemistry, University of Washington, Seattle, Washington, USA
| | - Wesley C. Van Voorhis
- Department of Medicine, Division of Allergy and Infectious Disease, Center for Emerging and Reemerging Infectious Disease (CERID), University of Washington, Seattle, Washington, USA
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Christiansen C, Maus D, Hoppenz E, Murillo-León M, Hoffmann T, Scholz J, Melerowicz F, Steinfeldt T, Seeber F, Blume M. In vitro maturation of Toxoplasma gondii bradyzoites in human myotubes and their metabolomic characterization. Nat Commun 2022; 13:1168. [PMID: 35246532 PMCID: PMC8897399 DOI: 10.1038/s41467-022-28730-w] [Citation(s) in RCA: 18] [Impact Index Per Article: 9.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/09/2021] [Accepted: 02/02/2022] [Indexed: 12/15/2022] Open
Abstract
The apicomplexan parasite Toxoplasma gondii forms bradyzoite-containing tissue cysts that cause chronic and drug-tolerant infections. However, current in vitro models do not allow long-term culture of these cysts to maturity. Here, we developed a human myotube-based in vitro culture model of functionally mature tissue cysts that are orally infectious to mice and tolerate exposure to a range of antibiotics and temperature stresses. Metabolomic characterization of purified cysts reveals global changes that comprise increased levels of amino acids and decreased abundance of nucleobase- and tricarboxylic acid cycle-associated metabolites. In contrast to fast replicating tachyzoite forms of T. gondii these tissue cysts tolerate exposure to the aconitase inhibitor sodium fluoroacetate. Direct access to persistent stages of T. gondii under defined cell culture conditions will be essential for the dissection of functionally important host-parasite interactions and drug evasion mechanisms. It will also facilitate the identification of new strategies for therapeutic intervention. Bradyzoites are a quiescent form of Toxoplasma gondii enclosed in cysts during chronic infections. Here, Christiansen et al. develop a human myotube-based in vitro culture model of cysts that are infectious to mice and characterize their metabolism in comparison to fast replicating tachyzoites.
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Affiliation(s)
- Céline Christiansen
- NG2: Metabolism of Microbial Pathogens, Robert Koch-Institute, 13353, Berlin, Germany
| | - Deborah Maus
- NG2: Metabolism of Microbial Pathogens, Robert Koch-Institute, 13353, Berlin, Germany
| | - Ellen Hoppenz
- NG2: Metabolism of Microbial Pathogens, Robert Koch-Institute, 13353, Berlin, Germany
| | - Mateo Murillo-León
- Institute of Virology, Medical Center University of Freiburg, 79104, Freiburg, Germany.,Faculty of Medicine, University of Freiburg, 79104, Freiburg, Germany.,Faculty of Biology, University of Freiburg, 79104, Freiburg, Germany
| | - Tobias Hoffmann
- ZBS 4: Advanced Light and Electron Microscopy, Centre for Biological Threats and Special Pathogens 4, Robert Koch-Institute, 13353, Berlin, Germany
| | - Jana Scholz
- NG2: Metabolism of Microbial Pathogens, Robert Koch-Institute, 13353, Berlin, Germany
| | - Florian Melerowicz
- NG2: Metabolism of Microbial Pathogens, Robert Koch-Institute, 13353, Berlin, Germany
| | - Tobias Steinfeldt
- Institute of Virology, Medical Center University of Freiburg, 79104, Freiburg, Germany.,Faculty of Medicine, University of Freiburg, 79104, Freiburg, Germany
| | - Frank Seeber
- FG 16: Mycotic and Parasitic Agents and Mycobacteria, Robert Koch-Institute, 13353, Berlin, Germany
| | - Martin Blume
- NG2: Metabolism of Microbial Pathogens, Robert Koch-Institute, 13353, Berlin, Germany.
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Gaji RY, Sharp AK, Brown AM. Protein kinases in Toxoplasma gondii. Int J Parasitol 2021; 51:415-429. [PMID: 33581139 PMCID: PMC11065138 DOI: 10.1016/j.ijpara.2020.11.006] [Citation(s) in RCA: 15] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/17/2020] [Revised: 11/10/2020] [Accepted: 11/15/2020] [Indexed: 02/06/2023]
Abstract
Toxoplasma gondii is an obligatory intracellular pathogen that causes life threatening illness in immunodeficient individuals, miscarriage in pregnant woman, and blindness in newborn children. Similar to any other eukaryotic cell, protein kinases play critical and essential roles in the Toxoplasma life cycle. Accordingly, many studies have focused on identifying and defining the mechanism of function of these signalling proteins with a long-term goal to develop anti-Toxoplasma therapeutics. In this review, we briefly discuss classification and key components of the catalytic domain which are critical for functioning of kinases, with a focus on domains, families, and groups of kinases within Toxoplasma. More importantly, this article provides a comprehensive, current overview of research on kinase groups in Toxoplasma including the established eukaryotic AGC, CAMK, CK1, CMGC, STE, TKL families and the apicomplexan-specific FIKK, ROPK and WNG family of kinases. This work provides an overview and discusses current knowledge on Toxoplasma kinases including their localization, function, signalling network and role in acute and chronic pathogenesis, with a view towards the future in probing kinases as viable drug targets.
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Affiliation(s)
- Rajshekhar Y Gaji
- Department of Biomedical Sciences and Pathobiology, Virginia-Maryland College of Veterinary Medicine, Virginia Tech University, Blacksburg, VA, USA; Department of Microbiology and Immunology, University of Michigan, Ann Arbor, MI, USA.
| | - Amanda K Sharp
- Interdisciplinary Program in Genetics, Bioinformatics, and Computational Biology, Virginia Tech, Blacksburg, VA, USA
| | - Anne M Brown
- Department of Biochemistry, Virginia Tech, Blacksburg, VA, USA; University Libraries, Virginia Tech, Blacksburg, VA, USA
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Development of novel anti-malarial from structurally diverse library of molecules, targeting plant-like CDPK1, a multistage growth regulator of P. falciparum. Biochem J 2020; 477:1951-1970. [PMID: 32401306 DOI: 10.1042/bcj20200045] [Citation(s) in RCA: 13] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/18/2020] [Revised: 05/11/2020] [Accepted: 05/13/2020] [Indexed: 01/06/2023]
Abstract
Upon Plasmodium falciparum merozoites exposure to low [K+] environment in blood plasma, there is escalation of cytosolic [Ca2+] which activates Ca2+-Dependent Protein Kinase 1 (CDPK1), a signaling hub of intra-erythrocytic proliferative stages of parasite. Given its high abundance and multidimensional attributes in parasite life-cycle, this is a lucrative target for designing antimalarials. Towards this, we have virtually screened MyriaScreenII diversity collection of 10,000 drug-like molecules, which resulted in 18 compounds complementing ATP-binding pocket of CDPK1. In vitro screening for toxicity in mammalian cells revealed that these compounds are non-toxic in nature. Furthermore, SPR analysis demonstrated differential binding affinity of these compounds towards recombinantly purified CDPK1 protein. Selection of lead compound 1 was performed by evaluating their inhibitory effects on phosphorylation and ATP binding activities of CDPK1. Furthermore, in vitro biophysical evaluations by ITC and FS revealed that binding of compound 1 is driven by formation of energetically favorable non-covalent interactions, with different binding constants in presence and absence of Ca2+, and TSA authenticated stability of compound 1 bound CDPK1 complex. Finally, compound 1 strongly inhibited intra-erythrocytic growth of P. falciparum in vitro. Conceivably, we propose a novel CDPK1-selective inhibitor, step towards developing pan-CDPK kinase inhibitors, prerequisite for cross-stage anti-malarial protection.
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Herneisen AL, Sidik SM, Markus BM, Drewry DH, Zuercher WJ, Lourido S. Identifying the Target of an Antiparasitic Compound in Toxoplasma Using Thermal Proteome Profiling. ACS Chem Biol 2020; 15:1801-1807. [PMID: 32597628 DOI: 10.1021/acschembio.0c00369] [Citation(s) in RCA: 20] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/15/2022]
Abstract
Apicomplexan parasites include the causative agents of malaria and toxoplasmosis. Cell-based screens in Toxoplasma previously identified a chemical modulator of calcium signaling (ENH1) that blocked parasite egress from host cells and exhibited potent antiparasitic activity. To identify the targets of ENH1, we adapted thermal proteome profiling to Toxoplasma, which revealed calcium-dependent protein kinase 1 (CDPK1) as a target. We confirmed the inhibition of CDPK1 by ENH1 in vitro and in parasites by comparing alleles sensitive or resistant to ENH1. CDPK1 inhibition explained the block in egress; however, the effects of ENH1 on calcium homeostasis and parasite viability were CDPK1-independent, implicating additional targets. Thermal proteome profiling of lysates from parasites expressing the resistant allele of CDPK1 identified additional candidates associated with the mitochondria and the parasite pellicle-compartments that potentially function in calcium release and homeostasis. Our findings illustrate the promise of thermal profiling to identify druggable targets that modulate calcium signaling in apicomplexan parasites.
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Affiliation(s)
- Alice L. Herneisen
- Department of Biology, Massachusetts Institute of Technology, 30 Ames St, Cambridge, Massachusetts 02142, United States
- Whitehead Institute for Biomedical Research, 455 Main St, Cambridge, Massachusetts 02142, United States
| | - Saima M. Sidik
- Whitehead Institute for Biomedical Research, 455 Main St, Cambridge, Massachusetts 02142, United States
| | - Benedikt M. Markus
- Whitehead Institute for Biomedical Research, 455 Main St, Cambridge, Massachusetts 02142, United States
- Faculty of Biology, University of Freiburg, Schänzlestraße 1, Freiburg 79104, Germany
| | - David H. Drewry
- Structural Genomics Consortium, UNC Eshelman School of Pharmacy, University of North Carolina at Chapel Hill, Chapel Hill, North Carolina 27599, United States
- Division of Chemical Biology and Medicinal Chemistry, UNC Eshelman School of Pharmacy, University of North Carolina at Chapel Hill, Chapel Hill, North Carolina 27599, United States
| | - William J. Zuercher
- Structural Genomics Consortium, UNC Eshelman School of Pharmacy, University of North Carolina at Chapel Hill, Chapel Hill, North Carolina 27599, United States
| | - Sebastian Lourido
- Department of Biology, Massachusetts Institute of Technology, 30 Ames St, Cambridge, Massachusetts 02142, United States
- Whitehead Institute for Biomedical Research, 455 Main St, Cambridge, Massachusetts 02142, United States
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Glennon EKK, Austin LS, Arang N, Kain HS, Mast FD, Vijayan K, Aitchison JD, Kappe SHI, Kaushansky A. Alterations in Phosphorylation of Hepatocyte Ribosomal Protein S6 Control Plasmodium Liver Stage Infection. Cell Rep 2020; 26:3391-3399.e4. [PMID: 30893610 DOI: 10.1016/j.celrep.2019.02.085] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/08/2018] [Revised: 10/11/2018] [Accepted: 02/21/2019] [Indexed: 12/11/2022] Open
Abstract
Plasmodium parasites are highly selective when infecting hepatocytes and induce many changes within the host cell upon infection. While several host cell factors have been identified that are important for liver infection, our understanding of what facilitates the maintenance of infection remains incomplete. Here, we describe a role for phosphorylated ribosomal protein S6 (Ser235/236) (p-RPS6) in Plasmodium yoelii-infected hepatocytes. Blocking RPS6 phosphorylation prior to infection decreases the number of liver stage parasites within 24 h. Infected hepatocytes exhibit elevated levels of p-RPS6 while simultaneously abrogating the induction of phosphorylation of RPS6 in response to insulin stimulation. This is in contrast with the regulation of p-RPS6 by Toxoplasma gondii, which elevates levels of p-RPS6 after infection but does not alter the response to insulin. Our data support a model in which RPS6 phosphorylation is uncoupled from canonical regulators in Plasmodium-infected hepatocytes and is relied on by the parasite to maintain infection.
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Affiliation(s)
- Elizabeth K K Glennon
- Center for Infectious Disease Research, Seattle, WA 98109, USA; Seattle Children's Research Institute, Seattle, WA 98109, USA; Department of Global Health, University of Washington, Seattle, WA 98109, USA
| | - Laura S Austin
- Center for Infectious Disease Research, Seattle, WA 98109, USA
| | - Nadia Arang
- Center for Infectious Disease Research, Seattle, WA 98109, USA
| | - Heather S Kain
- Center for Infectious Disease Research, Seattle, WA 98109, USA
| | - Fred D Mast
- Center for Infectious Disease Research, Seattle, WA 98109, USA; Seattle Children's Research Institute, Seattle, WA 98109, USA; Institute for Systems Biology, Seattle, WA 98109, USA
| | - Kamalakannan Vijayan
- Center for Infectious Disease Research, Seattle, WA 98109, USA; Seattle Children's Research Institute, Seattle, WA 98109, USA
| | - John D Aitchison
- Center for Infectious Disease Research, Seattle, WA 98109, USA; Seattle Children's Research Institute, Seattle, WA 98109, USA; Institute for Systems Biology, Seattle, WA 98109, USA
| | - Stefan H I Kappe
- Center for Infectious Disease Research, Seattle, WA 98109, USA; Seattle Children's Research Institute, Seattle, WA 98109, USA; Department of Global Health, University of Washington, Seattle, WA 98109, USA
| | - Alexis Kaushansky
- Center for Infectious Disease Research, Seattle, WA 98109, USA; Seattle Children's Research Institute, Seattle, WA 98109, USA; Department of Global Health, University of Washington, Seattle, WA 98109, USA.
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Lyu J, Wang K, Ye M. Modification-free approaches to screen drug targets at proteome level. Trends Analyt Chem 2020. [DOI: 10.1016/j.trac.2019.06.024] [Citation(s) in RCA: 8] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/17/2022]
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Hydroxylamine and Carboxymethoxylamine Can Inhibit Toxoplasma gondii Growth through an Aspartate Aminotransferase-Independent Pathway. Antimicrob Agents Chemother 2020; 64:AAC.01889-19. [PMID: 31907178 DOI: 10.1128/aac.01889-19] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/17/2019] [Accepted: 12/23/2019] [Indexed: 12/19/2022] Open
Abstract
Toxoplasma gondii is an obligate intracellular protozoan parasite and a successful parasitic pathogen in diverse organisms and host cell types. Hydroxylamine (HYD) and carboxymethoxylamine (CAR) have been reported as inhibitors of aspartate aminotransferases (AATs) and interfere with the proliferation in Plasmodium falciparum Therefore, AATs are suggested as drug targets against Plasmodium The T. gondii genome encodes only one predicted AAT in both T. gondii type I strain RH and type II strain PLK. However, the effects of HYD and CAR, as well as their relationship with AAT, on T. gondii remain unclear. In this study, we found that HYD and CAR impaired the lytic cycle of T. gondii in vitro, including the inhibition of invasion or reinvasion, intracellular replication, and egress. Importantly, HYD and CAR could control acute toxoplasmosis in vivo Further studies showed that HYD and CAR could inhibit the transamination activity of rTgAAT in vitro However, our results confirmed that deficiency of AAT in both RH and PLK did not reduce the virulence in mice, although the growth ability of the parasites was affected in vitro HYD and CAR could still inhibit the growth of AAT-deficient parasites. These findings indicated that HYD and CAR inhibition of T. gondii growth and control of toxoplasmosis can occur in an AAT-independent pathway. Overall, further studies focusing on the elucidation of the mechanism of inhibition are warranted. Our study hints at new substrates of HYD and CAR as potential drug targets to inhibit T. gondii growth.
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Guo Z, Song T, Xue Z, Liu P, Zhang M, Zhang X, Zhang Z. Using CETSA assay and a mathematical model to reveal dual Bcl-2/Mcl-1 inhibition and on-target mechanism for ABT-199 and S1. Eur J Pharm Sci 2020; 142:105105. [DOI: 10.1016/j.ejps.2019.105105] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/31/2019] [Revised: 10/06/2019] [Accepted: 10/10/2019] [Indexed: 12/17/2022]
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Bumped kinase inhibitor 1369 is effective against Cystoisospora suis in vivo and in vitro. INTERNATIONAL JOURNAL FOR PARASITOLOGY-DRUGS AND DRUG RESISTANCE 2019; 10:9-19. [PMID: 30959327 PMCID: PMC6453670 DOI: 10.1016/j.ijpddr.2019.03.004] [Citation(s) in RCA: 10] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 03/09/2019] [Revised: 03/25/2019] [Accepted: 03/28/2019] [Indexed: 12/22/2022]
Abstract
Cystoisosporosis is a leading diarrheal disease in suckling piglets. With the confirmation of resistance against the only available drug toltrazuril, there is a substantial need for novel therapeutics to combat the infection and its negative effects on animal health. In closely related apicomplexan species, bumped kinase inhibitors (BKIs) targeting calcium-dependent protein kinase 1 (CDPK1) were shown to be effective in inhibiting host-cell invasion and parasite growth. Therefore, the gene coding for Cystoisospora suis CDPK1 (CsCDPK1) was identified and cloned to investigate activity and thermal stabilization of the recombinant CsCDPK1 enzyme by BKI 1369. In this comprehensive study, the efficacy, safety and pharmacokinetics of BKI 1369 in piglets experimentally infected with Cystoisospora suis (toltrazuril-sensitive, Wien-I and toltrazuril-resistant, Holland-I strains) were determined in vivo and in vitro using an established animal infection model and cell culture, respectively. BKI 1369 inhibited merozoite proliferation in intestinal porcine epithelial cells-1 (IPEC-1) by at least 50% at a concentration of 40 nM, and proliferation was almost completely inhibited (>95%) at 200 nM. Nonetheless, exposure of infected cultures to 200 nM BKI 1369 for five days did not induce structural alterations in surviving merozoites as confirmed by transmission electron microscopy. Five-day treatment with BKI 1369 (10 mg/kg BW twice a day) effectively suppressed oocyst excretion and diarrhea and improved body weight gains in treated piglets without obvious side effects for both toltrazuril-sensitive, Wien-I and resistant, Holland-I C. suis strains. The plasma concentration of BKI 1369 in piglets increased to 11.7 μM during treatment, suggesting constant drug accumulation and exposure of parasites to the drug. Therefore, oral applications of BKI 1369 could potentially be a therapeutic alternative against porcine cystoisosporosis. For use in pigs, future studies on BKI 1369 should be directed towards ease of drug handling and minimizing treatment frequencies. Oral application of BKI 1369 effectively reduced oocyst excretion and diarrhea in Cystoisospora suis infected piglets. 200 nM of BKI 1369 almost completely suppressed parasite proliferation in vitro. IC50 and IC95 concentrations of BKI 1369 did not induce morphological alterations in in vitro cultured merozoites. Cystoisosporasuis CDPK1, the putative target of BKI 1369, has glycine as gatekeeper residue.
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