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Kohoutova Z, Malinak D, Andrys R, Svobodova J, Psotka M, Schmidt M, Prchal L, Musilek K. Charged pyridinium oximes with thiocarboxamide moiety are equally or less effective reactivators of organophosphate-inhibited cholinesterases compared to analogous carboxamides. J Enzyme Inhib Med Chem 2022; 37:760-767. [PMID: 35193448 PMCID: PMC8881075 DOI: 10.1080/14756366.2022.2041628] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022] Open
Abstract
The organophosphorus antidotes, so-called oximes, are able to restore the enzymatic function of acetylcholinesterase (AChE) or butyrylcholinesterase (BChE) via cleavage of organophosphate from the active site of the phosphylated enzyme. In this work, the charged pyridinium oximes containing thiocarboxamide moiety were designed, prepared and tested. Their stability and pKa properties were found to be analogous to parent carboxamides (K027, K048 and K203). The inhibitory ability of thiocarboxamides was found in low µM levels for AChE and high µM levels for BChE. Their reactivation properties were screened on human recombinant AChE and BChE inhibited by nerve agent surrogates and paraoxon. One thiocarboxamide was able to effectively restore function of NEMP- and NEDPA-AChE, whereas two thiocarboxamides were able to reactivate BChE inhibited by all tested organophosphates. These results were confirmed by reactivation kinetics, where thiocarboxamides were proved to be effective, but less potent reactivators if compared to carboxamides.
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Affiliation(s)
- Zuzana Kohoutova
- Faculty of Science, Department of Chemistry, University of Hradec Kralove, Hradec Kralove, Czech Republic
| | - David Malinak
- Faculty of Science, Department of Chemistry, University of Hradec Kralove, Hradec Kralove, Czech Republic.,Biomedical Research Centre, University Hospital in Hradec Kralove, Hradec Kralove, Czech Republic
| | - Rudolf Andrys
- Faculty of Science, Department of Chemistry, University of Hradec Kralove, Hradec Kralove, Czech Republic
| | - Jana Svobodova
- Faculty of Science, Department of Chemistry, University of Hradec Kralove, Hradec Kralove, Czech Republic
| | - Miroslav Psotka
- Faculty of Science, Department of Chemistry, University of Hradec Kralove, Hradec Kralove, Czech Republic.,Biomedical Research Centre, University Hospital in Hradec Kralove, Hradec Kralove, Czech Republic
| | - Monika Schmidt
- Faculty of Science, Department of Chemistry, University of Hradec Kralove, Hradec Kralove, Czech Republic.,Biomedical Research Centre, University Hospital in Hradec Kralove, Hradec Kralove, Czech Republic
| | - Lukas Prchal
- Biomedical Research Centre, University Hospital in Hradec Kralove, Hradec Kralove, Czech Republic
| | - Kamil Musilek
- Faculty of Science, Department of Chemistry, University of Hradec Kralove, Hradec Kralove, Czech Republic.,Biomedical Research Centre, University Hospital in Hradec Kralove, Hradec Kralove, Czech Republic
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2
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In Vitro Evaluation of Neutral Aryloximes as Reactivators for Electrophorus eel Acetylcholinesterase Inhibited by Paraoxon. Biomolecules 2019; 9:biom9100583. [PMID: 31597234 PMCID: PMC6843506 DOI: 10.3390/biom9100583] [Citation(s) in RCA: 10] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/09/2019] [Revised: 10/01/2019] [Accepted: 10/04/2019] [Indexed: 02/08/2023] Open
Abstract
Casualties caused by organophosphorus pesticides are a burden for health systems in developing and poor countries. Such compounds are potent acetylcholinesterase irreversible inhibitors, and share the toxic profile with nerve agents. Pyridinium oximes are the only clinically available antidotes against poisoning by these substances, but their poor penetration into the blood-brain barrier hampers the efficient enzyme reactivation at the central nervous system. In searching for structural factors that may be explored in future SAR studies, we evaluated neutral aryloximes as reactivators for paraoxon-inhibited Electrophorus eel acetylcholinesterase. Our findings may result into lead compounds, useful for development of more active compounds for emergencies and supportive care.
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3
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Bharate SB, Chao CK, Thompson CM. Comparison of the reactivation rates of acetylcholinesterase modified by structurally different organophosphates using novel pyridinium oximes. ENVIRONMENTAL TOXICOLOGY AND PHARMACOLOGY 2019; 71:103218. [PMID: 31302432 PMCID: PMC6736693 DOI: 10.1016/j.etap.2019.103218] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/24/2018] [Revised: 03/27/2019] [Accepted: 06/24/2019] [Indexed: 06/10/2023]
Abstract
A novel panel of oximes were synthesized, which have displayed varying degree of reactivation ability towards different organophosphorus (OP) modified cholinesterases. In the present article, we report a comparative reactivation profile of a series of quaternary pyridinium-oximes for electric eel acetylcholinesterase (EEAChE) inhibited by the organophosphorus (OP) inhibitors methyl paraoxon (MePOX), ethyl paraoxon (POX; paraoxon) and diisopropyl fluorophosphate (DFP) that are distinguishable as dimethoxyphosphoryl, diethoxyphosphoryl and diisopropoxyphosphoryl AChE-OP-adducts. Most of the 59-oximes tested led to faster and more extensive reactivation of MePOX- and POX-inhibited EEAChE as compared to DFP-modified EEAChE. All were effective reactivators of three OP-modified EEAChE conjugates showing 18-21% reactivation for DFP-inhibited AChE and ≥45% reactivation for MePOX- and POX-inhibited EEAChE. Oximes 7 and 8 showed kr values better than pralidoxime (1) for DFP-inhibited EEAChE. Reactivation rates determined at different inhibition times showed no significant change in kr values during 0-90 min incubation with three OPs. However, a 34-72% decrease in kr for MePOX and POX and > 95% decrease in kr for DFP-inhibited EEAChE was observed after 24 h of OP-exposure (aging).
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Affiliation(s)
- Sandip B Bharate
- The Center for Structural and Functional Neuroscience, Department of Biomedical and Pharmaceutical Sciences, The University of Montana, Missoula, MT, 59812, USA; Medicinal Chemistry Division, CSIR-Indian Institute of Integrative Medicine, Canal Road, Jammu, 180001, India.
| | - Chih-Kai Chao
- The Center for Structural and Functional Neuroscience, Department of Biomedical and Pharmaceutical Sciences, The University of Montana, Missoula, MT, 59812, USA
| | - Charles M Thompson
- The Center for Structural and Functional Neuroscience, Department of Biomedical and Pharmaceutical Sciences, The University of Montana, Missoula, MT, 59812, USA.
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4
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Cavalcante SFDA, Kitagawa DAS, Rodrigues RB, Bernardo LB, da Silva TN, Dos Santos WV, Correa ABDA, de Almeida JSFD, França TCC, Kuča K, Simas ABC. Synthesis and in vitro evaluation of neutral aryloximes as reactivators of Electrophorus eel acetylcholinesterase inhibited by NEMP, a VX surrogate. Chem Biol Interact 2019; 309:108682. [PMID: 31163137 DOI: 10.1016/j.cbi.2019.05.048] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/27/2019] [Revised: 04/23/2019] [Accepted: 05/27/2019] [Indexed: 01/08/2023]
Abstract
Casualties caused by nerve agents, potent acetylcholinesterase inhibitors, have attracted attention from media recently. Poisoning with these chemicals may be fatal if not correctly addressed. Therefore, research on novel antidotes is clearly warranted. Pyridinium oximes are the only clinically available compounds, but poor penetration into the blood-brain barrier hampers efficient enzyme reactivation at the central nervous system. In searching for structural factors that may be explored in SAR studies, we synthesized and evaluated neutral aryloximes as reactivators for acetylcholinesterase inhibited by NEMP, a VX surrogate. Although few tested compounds reached comparable reactivation results with clinical standards, they may be considered as leads for further optimization.
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Affiliation(s)
- Samir F de A Cavalcante
- Brazilian Army Institute of Chemical, Biological, Radiological and Nuclear Defense (IDQBRN), Avenida das Américas 28705, Rio de Janeiro, 23020-470, Brazil; Walter Mors Institute of Research on Natural Products (IPPN), Federal University of Rio de Janeiro (UFRJ), CCS, Bloco H, Rio de Janeiro, 21941-902, Brazil; University Castelo Branco (UCB), School of Pharmacy, Avenida Santa Cruz 1631, Rio de Janeiro, 21710-255, Brazil; Department of Chemistry, Faculty of Science, University of Hradec Králové, Rokitanskeho 62, 50003, Hradec Králové, Czech Republic.
| | - Daniel A S Kitagawa
- Laboratory of Molecular Modelling Applied to Chemical and Biological Defense (LMACDB), Praça General Tibúrcio 80, Rio de Janeiro, 22290-270, Brazil
| | - Rafael B Rodrigues
- Brazilian Army Institute of Chemical, Biological, Radiological and Nuclear Defense (IDQBRN), Avenida das Américas 28705, Rio de Janeiro, 23020-470, Brazil
| | - Leandro B Bernardo
- Brazilian Army Institute of Chemical, Biological, Radiological and Nuclear Defense (IDQBRN), Avenida das Américas 28705, Rio de Janeiro, 23020-470, Brazil
| | - Thiago N da Silva
- University Castelo Branco (UCB), School of Pharmacy, Avenida Santa Cruz 1631, Rio de Janeiro, 21710-255, Brazil
| | - Wellington V Dos Santos
- Emergency and Rescue Department (DSE), Rio de Janeiro State Fire Department (CBMERJ), Praça São Salvador 4, Rio de Janeiro, 22231-170, Brazil; University Universus Veritas (UNIVERITAS), School of Biomedicine, Rua Marquês de Abrantes 55, Rio de Janeiro, 22230-060, Brazil
| | - Ana Beatriz de A Correa
- Brazilian Army Institute of Chemical, Biological, Radiological and Nuclear Defense (IDQBRN), Avenida das Américas 28705, Rio de Janeiro, 23020-470, Brazil
| | - Joyce S F D de Almeida
- Laboratory of Molecular Modelling Applied to Chemical and Biological Defense (LMACDB), Praça General Tibúrcio 80, Rio de Janeiro, 22290-270, Brazil
| | - Tanos C C França
- Department of Chemistry, Faculty of Science, University of Hradec Králové, Rokitanskeho 62, 50003, Hradec Králové, Czech Republic; Laboratory of Molecular Modelling Applied to Chemical and Biological Defense (LMACDB), Praça General Tibúrcio 80, Rio de Janeiro, 22290-270, Brazil
| | - Kamil Kuča
- Department of Chemistry, Faculty of Science, University of Hradec Králové, Rokitanskeho 62, 50003, Hradec Králové, Czech Republic
| | - Alessandro B C Simas
- Walter Mors Institute of Research on Natural Products (IPPN), Federal University of Rio de Janeiro (UFRJ), CCS, Bloco H, Rio de Janeiro, 21941-902, Brazil.
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Kuca K, Musilek K, Jun D, Zdarova-Karasova J, Nepovimova E, Soukup O, Hrabinova M, Mikler J, Franca TCC, Da Cunha EFF, De Castro AA, Valis M, Ramalho TC. A newly developed oxime K203 is the most effective reactivator of tabun-inhibited acetylcholinesterase. BMC Pharmacol Toxicol 2018; 19:8. [PMID: 29467029 PMCID: PMC5822599 DOI: 10.1186/s40360-018-0196-3] [Citation(s) in RCA: 45] [Impact Index Per Article: 7.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/07/2017] [Accepted: 01/25/2018] [Indexed: 11/30/2022] Open
Abstract
BACKGROUND Based on in vitro and in vivo rat experiments, the newly developed acetylcholinesterase (AChE) reactivator, K203, appears to be much more effective in the treatment of tabun poisonings than currently fielded oximes. METHODS To determine if this reactivating efficacy would extend to humans, studies were conducted in vitro using human brain homogenate as the source of AChE. The efficacy of K203 was compared with commercially available oximes; pralidoxime, obidoxime and asoxime (HI-6). RESULTS Reactivation studies showed that K203 was the most effective reactivator with a second order kinetic constant (kr) of 2142 min- 1. M- 1, which was 51 times higher than that obtained for obidoxime (kr = 42 min- 1. M- 1). Both pralidoxime and asoxime (HI-6) failed to significantly reactivate tabun-inhibited human AChE. DISCUSSION According to these results and previous studies, using K203, it appears that oxime K203 is the most effective reactivator of tabun-inhibited cholinesterase in several species including humans and should be considered as a possible medical countermeasure to tabun exposure.
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Affiliation(s)
- Kamil Kuca
- Biomedical Research Center, University Hospital Hradec Kralove, Hradec Kralove, Czech Republic.
- Department of Chemistry, Faculty of Science, University of Hradec Kralove, Hradec Kralove, Czech Republic.
| | - Kamil Musilek
- Biomedical Research Center, University Hospital Hradec Kralove, Hradec Kralove, Czech Republic
- Department of Chemistry, Faculty of Science, University of Hradec Kralove, Hradec Kralove, Czech Republic
| | - Daniel Jun
- Biomedical Research Center, University Hospital Hradec Kralove, Hradec Kralove, Czech Republic
- Faculty of Military Health Sciences, University of Defence, Hradec Kralove, Czech Republic
| | - Jana Zdarova-Karasova
- Biomedical Research Center, University Hospital Hradec Kralove, Hradec Kralove, Czech Republic
- Faculty of Military Health Sciences, University of Defence, Hradec Kralove, Czech Republic
| | - Eugenie Nepovimova
- Biomedical Research Center, University Hospital Hradec Kralove, Hradec Kralove, Czech Republic
- Department of Chemistry, Faculty of Science, University of Hradec Kralove, Hradec Kralove, Czech Republic
| | - Ondrej Soukup
- Biomedical Research Center, University Hospital Hradec Kralove, Hradec Kralove, Czech Republic
- Faculty of Military Health Sciences, University of Defence, Hradec Kralove, Czech Republic
| | - Martina Hrabinova
- Biomedical Research Center, University Hospital Hradec Kralove, Hradec Kralove, Czech Republic
- Faculty of Military Health Sciences, University of Defence, Hradec Kralove, Czech Republic
| | - John Mikler
- Defence Research and Development Canada - Suffield Research Centre, Department of National Defence, Suffield, Alberta, Canada
| | - Tanos C C Franca
- Center for Basic and Applied Research, Faculty of Informatics and Management, University of Hradec Kralove, Hradec Kralove, Czech Republic
- Department of Chemical Engineering, Military Institute of Engineering, Rio de Janeiro, RJ, 22290-270, Brazil
| | | | | | - Martin Valis
- Neurology Clinic, University Hospital Hradec Kralove, Hradec Kralove, Czech Republic
| | - Teodorico C Ramalho
- Center for Basic and Applied Research, Faculty of Informatics and Management, University of Hradec Kralove, Hradec Kralove, Czech Republic
- Department of Chemistry, Federal University of Lavras, Lavras/MG, Brazil
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6
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Musílek K, Kuča K, Jun D. Evaluation of Potency of Known Oximes (Pralidoxime, Trimedoxime, HI-6, Methoxime, Obidoxime) to in vitro Reactivate Acetylcholinesterase Inhibited by Pesticides (Chlorpyrifos and Methylchlorpyrifos and Nerve Agent (Russian VX). ACTA MEDICA (HRADEC KRÁLOVÉ) 2017. [DOI: 10.14712/18059694.2017.83] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 10/19/2022]
Abstract
Nerve agents and pesticides belong to the group of organophosphates. They are able to inhibit irreversibly the enzyme acetylcholinesterase (AChE). Acetylcholinesterase reactivators were designed for the treatment of nerve agent intoxications. Their potency to reactivate pesticide-inhibited AChE was many times evaluated. In this study, five commonly used AChE reactivators (pralidoxime, methoxime, HI-6, obidoxime, trimedoxime) for the reactivation of AChE inhibited by two pesticides (chlorpyrifos and methylchlorpyrifos) were used. Russian VX (nerve agent) as a member of nerve agents’ family was taken for comparison. Obtained results show that oximes developed against nerve agent intoxication are less effective for intoxication with organophosphorus pesticides. Especially, methylchlorpyrifos-inhibited AChE was found to be poorly reactivated by the compounds used.
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7
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Bobkova L. Synthesis and Research of Reactivation of Phosphorylated Cholinesterase by Quaternary Pyridinium-Aldoxime Salts. CHEMISTRY & CHEMICAL TECHNOLOGY 2015. [DOI: 10.23939/chcht09.03.281] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/19/2022]
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8
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Winter M, Wille T, Musilek K, Kuca K, Thiermann H, Worek F. Investigation of the reactivation kinetics of a large series of bispyridinium oximes with organophosphate-inhibited human acetylcholinesterase. Toxicol Lett 2015. [PMID: 26210933 DOI: 10.1016/j.toxlet.2015.07.007] [Citation(s) in RCA: 34] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/23/2022]
Abstract
The limited effectiveness of the established oximes obidoxime and pralidoxime resulted in ongoing research on novel oximes for the reactivation of acetylcholinesterase (AChE) inhibited by organophosphorus compounds (OP). In order to get more insight into the ability of bispyridinium oximes to reactivate human AChE inhibited by structurally different OP the reactivation kinetics of 31 compounds was determined with tabun-, cyclosarin- and paraoxon-inhibited AChE under identical experimental conditions. The determined affinity (KD), reactivity (kr) and hybrid reactivation rate constants (kr2) enabled theoretical calculations and gave insight into distinct structural features which are important for the reactivation of AChE inhibited by different OP. Several oximes with superior reactivating potency towards selective OP-AChE conjugates were identified but none of the tested oximes can be considered as a broad spectrum reactivator. In the end, the data of this and previous studies gives rise to the question whether further modifications of the bispyridinium structure could ever result in a universal reactivator or whether future research should be directed to different templates.
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Affiliation(s)
- Michael Winter
- Bundeswehr Institute of Pharmacology and Toxicology, Munich, Germany
| | - Timo Wille
- Bundeswehr Institute of Pharmacology and Toxicology, Munich, Germany
| | - Kamil Musilek
- University of Hradec Kralove, Faculty of Science, Department of Chemistry, Hradec Králové, Czech Republic
| | - Kamil Kuca
- University of Hradec Kralove, Faculty of Science, Department of Chemistry, Hradec Králové, Czech Republic; University Hospital Hradec Kralove, Biomedical Research Center, Hradec Králové, Czech Republic
| | - Horst Thiermann
- Bundeswehr Institute of Pharmacology and Toxicology, Munich, Germany
| | - Franz Worek
- Bundeswehr Institute of Pharmacology and Toxicology, Munich, Germany.
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Pooja P, Aggarwal S, Tiwari AK, Kumar V, Pratap R, Singh G, Mishra AK. Novel pyridinium oximes: synthesis, molecular docking and in vitro reactivation studies. RSC Adv 2015. [DOI: 10.1039/c4ra14696d] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022] Open
Abstract
A computational approach has been attempted for the screening of 4-pyridoxinium (4P) ring based reactivators for paraoxon inhibited AChE.
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Affiliation(s)
- Pooja Pooja
- Division of Cyclotron and Radiopharmaceutical Sciences
- Institute of Nuclear Medicine and Allied Sciences
- Delhi-110054
- India
- Department of Chemistry
| | - S. Aggarwal
- Division of Cyclotron and Radiopharmaceutical Sciences
- Institute of Nuclear Medicine and Allied Sciences
- Delhi-110054
- India
- Department of Chemistry
| | - A. K. Tiwari
- Division of Cyclotron and Radiopharmaceutical Sciences
- Institute of Nuclear Medicine and Allied Sciences
- Delhi-110054
- India
| | - V. Kumar
- Division of Cyclotron and Radiopharmaceutical Sciences
- Institute of Nuclear Medicine and Allied Sciences
- Delhi-110054
- India
| | - R. Pratap
- Department of Chemistry
- University of Delhi
- Delhi-110054
- India
| | - G. Singh
- Department of Chemistry
- University of Delhi
- Delhi-110054
- India
| | - A. K. Mishra
- Division of Cyclotron and Radiopharmaceutical Sciences
- Institute of Nuclear Medicine and Allied Sciences
- Delhi-110054
- India
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10
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Reactivation kinetics of 31 structurally different bispyridinium oximes with organophosphate-inhibited human butyrylcholinesterase. Arch Toxicol 2014; 89:405-14. [DOI: 10.1007/s00204-014-1288-5] [Citation(s) in RCA: 20] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/02/2014] [Accepted: 05/28/2014] [Indexed: 02/02/2023]
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11
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Chadha N, Tiwari AK, Kumar V, Lal S, Milton MD, Mishra AK. Oxime-dipeptides as anticholinesterase, reactivator of phosphonylated-serine of AChE catalytic triad: probing the mechanistic insight by MM-GBSA, dynamics simulations and DFT analysis. J Biomol Struct Dyn 2014; 33:978-90. [DOI: 10.1080/07391102.2014.921793] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/25/2022]
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12
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Konidaris KF, Dalkas GA, Katsoulakou E, Pairas G, Raptopoulou CP, Lamari FN, Spyroulias GA, Manessi-Zoupa E. ZnII/pyridyloxime complexes as potential reactivators of OP-inhibited acetylcholinesterase: In vitro and docking simulation studies. J Inorg Biochem 2014; 134:12-9. [DOI: 10.1016/j.jinorgbio.2013.12.011] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/17/2013] [Revised: 12/26/2013] [Accepted: 12/26/2013] [Indexed: 10/25/2022]
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13
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Worek F, von der Wellen J, Musilek K, Kuca K, Thiermann H. Reactivation kinetics of a homologous series of bispyridinium bis-oximes with nerve agent-inhibited human acetylcholinesterase. Arch Toxicol 2012; 86:1379-86. [PMID: 22437842 DOI: 10.1007/s00204-012-0842-2] [Citation(s) in RCA: 28] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/16/2012] [Accepted: 03/06/2012] [Indexed: 10/28/2022]
Abstract
The reactivation of organophosphorus compound (OP)-inhibited acetylcholinesterase (AChE) by oximes is inadequate in case of different OP nerve agents. This fact led to the synthesis of numerous novel oximes by different research groups in order to identify more effective reactivators. In the present study, we investigated the reactivation kinetics of a homologous series of bispyridinium bis-oximes bearing a (E)-but-2-ene linker with tabun-, sarin-, and cyclosarin-inhibited human AChE. In part, marked differences in affinity and reactivity of the investigated oximes toward OP-inhibited human AChE were recorded. These properties depended on the position of the oxime groups and the inhibitor. None of the tested oximes was equally effective against all used OPs. In addition, the data indicate that a (E)-but-2-ene linker decreased in most cases the reactivating potency in comparison to oximes bearing an oxybismethylene linker, e.g., obidoxime and HI-6. The results of this study give further insight into structural requirements for oxime reactivators, underline the necessity to investigate the kinetic interactions of oximes and AChE with structurally different OP inhibitors, and point to the difficulty to develop an oxime reactivator which is efficient against a broad spectrum of OPs.
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Affiliation(s)
- Franz Worek
- Bundeswehr Institute of Pharmacology and Toxicology, Munich, Germany.
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14
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Jun D, Stodulka P, Hrabinova M, Pohanka M, Doleza B, Kuca K. TLC analysis of twelve different salts of oxime HI-6 — Reactivator of nerve agent inhibited AChE. JPC-J PLANAR CHROMAT 2011. [DOI: 10.1556/jpc.24.2011.2.3] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/19/2022]
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15
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Musilek K, Pavlikova R, Marek J, Komloova M, Holas O, Hrabinova M, Pohanka M, Dohnal V, Dolezal M, Gunn-Moore F, Kuca K. The preparation, in vitro screening and molecular docking of symmetrical bisquaternary cholinesterase inhibitors containing a but-(2E)-en-1,4-diyl connecting linkage. J Enzyme Inhib Med Chem 2011; 26:245-53. [DOI: 10.3109/14756366.2010.496362] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/13/2022] Open
Affiliation(s)
- Kamil Musilek
- University of Defence, Faculty of Military Health Sciences, Department of Toxicology, Trebesska 1575, Hradec Kralove, Czech Republic
- University of Jan Evangelista Purkynje, Faculty of Science, Department of Chemistry, Ceske mladeze 8, Usti nad Labem, Czech Republic
| | - Ruzena Pavlikova
- University of Defence, Faculty of Military Health Sciences, Department of Toxicology, Trebesska 1575, Hradec Kralove, Czech Republic
| | - Jan Marek
- University of Defence, Faculty of Military Health Sciences, Department of Toxicology, Trebesska 1575, Hradec Kralove, Czech Republic
| | - Marketa Komloova
- Charles University, Faculty of Pharmacy, Department of Pharmaceutical Chemistry and Drug Control, Heyrovskeho 1203, Hradec Kralove, Czech Republic
| | - Ondrej Holas
- Charles University, Faculty of Pharmacy, Department of Pharmaceutical Chemistry and Drug Control, Heyrovskeho 1203, Hradec Kralove, Czech Republic
| | - Martina Hrabinova
- University of Defence, Faculty of Military Health Sciences, Centre of Advanced Studies, Trebesska 1575, Hradec Kralove, Czech Republic
| | - Miroslav Pohanka
- University of Defence, Faculty of Military Health Sciences, Centre of Advanced Studies, Trebesska 1575, Hradec Kralove, Czech Republic
| | - Vlastimil Dohnal
- University of Jan Evangelista Purkynje, Faculty of Science, Department of Chemistry, Ceske mladeze 8, Usti nad Labem, Czech Republic
| | - Martin Dolezal
- Charles University, Faculty of Pharmacy, Department of Pharmaceutical Chemistry and Drug Control, Heyrovskeho 1203, Hradec Kralove, Czech Republic
| | - Frank Gunn-Moore
- University of St. Andrews, School of Biology, Bute Building, St. Andrews, Fife, UK
| | - Kamil Kuca
- University of Defence, Faculty of Military Health Sciences, Centre of Advanced Studies, Trebesska 1575, Hradec Kralove, Czech Republic
- University of Jan Evangelista Purkynje, Faculty of Science, Department of Chemistry, Ceske mladeze 8, Usti nad Labem, Czech Republic
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16
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Acharya J, Dubey DK, Srivastava AK, Raza SK. In vitro reactivation of sarin-inhibited human acetylcholinesterase (AChE) by bis-pyridinium oximes connected by xylene linkers. Toxicol In Vitro 2011; 25:251-6. [DOI: 10.1016/j.tiv.2010.07.024] [Citation(s) in RCA: 21] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/18/2010] [Revised: 07/06/2010] [Accepted: 07/28/2010] [Indexed: 11/26/2022]
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17
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Luo C, Chambers C, Yang Y, Saxena A. Mechanism for potent reactivation ability of H oximes analyzed by reactivation kinetic studies with cholinesterases from different species. Chem Biol Interact 2010; 187:185-90. [DOI: 10.1016/j.cbi.2010.01.018] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/30/2009] [Revised: 01/07/2010] [Accepted: 01/13/2010] [Indexed: 11/17/2022]
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18
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Kuca K, Cabal J, Jun D, Musilek K, Soukup O, Pohanka M, Pejchal J, Oh KA, Yang GY, Jung YS. Reactivation of VX-inhibited AChE by novel oximes having two oxygen atoms in the linker. ENVIRONMENTAL TOXICOLOGY AND PHARMACOLOGY 2010; 30:85-87. [PMID: 21787634 DOI: 10.1016/j.etap.2010.03.011] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/12/2009] [Revised: 03/09/2010] [Accepted: 03/10/2010] [Indexed: 05/31/2023]
Abstract
Two newly developed AChE reactivators possessing two oxime groups in 4-position of the pyridinium rings with linkers CH(2)O(CH(2))(2)OCH(2) and CH(2)O(CH(2))(4)OCH(2) were tested for their potency to reactivate VX-inhibited AChE. Their reactivation potency was compared with currently available oximes such as pralidoxime, obidoxime and HI-6. Appropriate constants (affinity towards the intact and inhibited enzyme, reactivation rate) characterizing the reactivation process were determined. According to the data obtained, a new oxime with CH(2)O(CH(2))(2)OCH(2) linker reached as high reactivation potency as HI-6. The percentage of reactivation of the oxime with CH(2)O(CH(2))(2)OCH(2) linker was comparable to that of obidoxime at a concentration 10(-3)M. Hence, these oximes may be worthy of future development for the treatment of nerve agent intoxications, especially, with lipophilic agents such as soman and cyclosarin.
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Affiliation(s)
- Kamil Kuca
- Center of Advanced Studies, Hradec Kralove, Czech Republic; Department of Toxicology, Faculty of Military Health Sciences, Hradec Kralove, Czech Republic
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Karasova JZ, Stodulka P, Pohanka M, Kuca K. In Vitro Screening of Blood-Brain Barrier Penetration of Monoquaternary Acetylcholinesterase Reactivators. ANAL LETT 2010. [DOI: 10.1080/00032710903502082] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/12/2022]
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20
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Rook Y, Schmidtke KU, Gaube F, Schepmann D, Wünsch B, Heilmann J, Lehmann J, Winckler T. Bivalent β-Carbolines as Potential Multitarget Anti-Alzheimer Agents. J Med Chem 2010; 53:3611-7. [DOI: 10.1021/jm1000024] [Citation(s) in RCA: 113] [Impact Index Per Article: 8.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Affiliation(s)
- Yvonne Rook
- Institut für Pharmazie, Lehrstuhl für Pharmazeutische/Medizinische Chemie, Friedrich-Schiller-Universität Jena, Germany
| | - Kai-Uwe Schmidtke
- Institut für Pharmazie, Lehrstuhl für Pharmazeutische Biologie, Friedrich-Schiller-Universität Jena, Semmelweisstrasse 10, D-07743 Jena, Germany
| | - Friedemann Gaube
- Institut für Pharmazie, Lehrstuhl für Pharmazeutische Biologie, Friedrich-Schiller-Universität Jena, Semmelweisstrasse 10, D-07743 Jena, Germany
| | - Dirk Schepmann
- Institut für Pharmazeutische und Medizinische Chemie der Westfälischen Wilhelms-Universität Münster, Germany
| | - Bernhard Wünsch
- Institut für Pharmazeutische und Medizinische Chemie der Westfälischen Wilhelms-Universität Münster, Germany
| | - Jörg Heilmann
- Lehrstuhl für Pharmazeutische Biologie, Universität Regensburg, Germany
| | - Jochen Lehmann
- Institut für Pharmazie, Lehrstuhl für Pharmazeutische/Medizinische Chemie, Friedrich-Schiller-Universität Jena, Germany
| | - Thomas Winckler
- Institut für Pharmazie, Lehrstuhl für Pharmazeutische Biologie, Friedrich-Schiller-Universität Jena, Semmelweisstrasse 10, D-07743 Jena, Germany
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Musilek K, Holas O, Misik J, Pohanka M, Novotny L, Dohnal V, Opletalova V, Kuca K. Monooxime-monocarbamoyl Bispyridinium Xylene-Linked Reactivators of Acetylcholinesterase-Synthesis, In vitro and Toxicity Evaluation, and Docking Studies. ChemMedChem 2010; 5:247-54. [DOI: 10.1002/cmdc.200900455] [Citation(s) in RCA: 34] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/10/2022]
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22
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Bharate SB, Guo L, Reeves TE, Cerasoli DM, Thompson CM. Bisquaternary pyridinium oximes: Comparison of in vitro reactivation potency of compounds bearing aliphatic linkers and heteroaromatic linkers for paraoxon-inhibited electric eel and recombinant human acetylcholinesterase. Bioorg Med Chem 2010; 18:787-94. [PMID: 20005727 PMCID: PMC2818686 DOI: 10.1016/j.bmc.2009.11.052] [Citation(s) in RCA: 22] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/04/2009] [Revised: 11/18/2009] [Accepted: 11/21/2009] [Indexed: 11/26/2022]
Abstract
Oxime reactivators are the drugs of choice for the post-treatment of OP (organophosphorus) intoxication and used widely for mechanistic and kinetic studies of OP-inhibited cholinesterases. The purpose of the present study was to evaluate new oxime compounds to reactivate acetylcholinesterase (AChE) inhibited by the OP paraoxon. Several new bisquaternary pyridinium oximes with heterocyclic linkers along with some known bisquaternary pyridinium oximes bearing aliphatic linkers were synthesized and evaluated for their in vitro reactivation potency against paraoxon-inhibited electric eel acetylcholinesterase (EeAChE) and recombinant human acetylcholinesterase (rHuAChE). Results herein indicate that most of the compounds are better reactivators of EeAChE than of rHuAChE. The reactivation potency of two different classes of compounds with varying linker chains was compared and observed that the structure of the connecting chain is an important factor for the activity of the reactivators. At a higher concentration (10(-3)M), compounds bearing aliphatic linker showed better reactivation than compounds with heterocyclic linkers. Interestingly, oximes with a heterocyclic linker inhibited AChE at higher concentration (10(-3)M), whereas their ability to reactivate was increased at lower concentrations (10(-4)M and 10(-5)M). Compounds bearing either a thiophene linker 26, 46 or a furan linker 31 showed 59%, 49% and 52% reactivation of EeAChE, respectively, at 10(-5)M. These compounds showed 14%, 6% and 15% reactivation of rHuAChE at 10(-4)M. Amongst newly synthesized analogs with heterocyclic linkers (26-35 and 45-46), compound 31, bearing furan linker chain, was found to be the most effective reactivator with a k(r) 0.042min(-1), which is better than obidoxime (3) for paraoxon-inhibited EeAChE. Compound 31 showed a k(r) 0.0041min(-1) that is near equal to pralidoxime (1) for paraoxon-inhibited rHuAChE.
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Affiliation(s)
- Sandip B. Bharate
- NIH COBRE Center for Structural and Functional Neuroscience, Department of Biomedical and Pharmaceutical Sciences, The University of Montana, Missoula, MT 59812, USA
| | - Lilu Guo
- ATERIS Technologies LLC, 901 N Orange Street, Missoula, MT 59802, USA
| | - Tony E. Reeves
- USAMRICD, Research Division, Physiology and Immunology Branch, 3100 Ricketts Point Road, APG, MD 21010, USA
| | - Douglas M. Cerasoli
- USAMRICD, Research Division, Physiology and Immunology Branch, 3100 Ricketts Point Road, APG, MD 21010, USA
| | - Charles M. Thompson
- NIH COBRE Center for Structural and Functional Neuroscience, Department of Biomedical and Pharmaceutical Sciences, The University of Montana, Missoula, MT 59812, USA
- ATERIS Technologies LLC, 901 N Orange Street, Missoula, MT 59802, USA
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Musilek K, Dolezal M, Gunn-Moore F, Kuca K. Design, evaluation and structure-activity relationship studies of the AChE reactivators against organophosphorus pesticides. Med Res Rev 2009; 31:548-75. [PMID: 20027669 DOI: 10.1002/med.20192] [Citation(s) in RCA: 89] [Impact Index Per Article: 5.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022]
Abstract
Organophosphate pesticides (OPPs; e.g. chlorpyrifos, diazinon, paraoxon) are a wide and heterogeneous group of organophosphorus compounds. Their biological activity of inhibiting acetylcholinesterase (AChE) or butyrylcholinesterase (BChE) ranks them as life endangering agents. The necessary treatment after OPP exposure involves the use of parasympatolytics (e.g. atropine), oxime reactivators (e.g. obidoxime), and anticonvulsive drugs (e.g. diazepam). Therefore, the reactivators of AChE are essential compounds in the treatment of OPP intoxications. Commercial AChE reactivators (e.g. pralidoxime, HI-6, obidoxime, trimedoxime, methoxime) were originally developed for other members of the organophosphate family, such as nerve agents (e.g. sarin, soman, tabun, VX). Pralidoxime, HI-6, and methoxime were found to be weak reactivators of OPP-inhibited AChE. Obidoxime and trimedoxime showed satisfactory reactivation against various OPPs with minor toxicity issues. During the last two decades, the treatment of OPP exposure has become more widely discussed because of growing agricultural production, industrialization, and harmful social issues (e.g. suicides). In this review is the summarized design, evaluation, and structure-activity relationship studies of recently produced AChE reactivators. Since pralidoxime, over 300 oximes have been produced or tested against OPP poisoning, and several novel compounds show very promising abilities as comparable (or higher) to commercial oximes. Some of these are highlighted for their further testing of OPP exposure and, additionally, the main structure-activity relationship of AChE reactivators against OPP is discussed.
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Affiliation(s)
- Kamil Musilek
- Department of Toxicology, Trebesska, Hradec Kralove, Czech Republic.
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25
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Bharate SB, Guo L, Reeves TE, Cerasoli DM, Thompson CM. New series of monoquaternary pyridinium oximes: Synthesis and reactivation potency for paraoxon-inhibited electric eel and recombinant human acetylcholinesterase. Bioorg Med Chem Lett 2009; 19:5101-4. [PMID: 19640713 DOI: 10.1016/j.bmcl.2009.07.035] [Citation(s) in RCA: 14] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/03/2009] [Revised: 06/21/2009] [Accepted: 07/02/2009] [Indexed: 10/20/2022]
Abstract
The preparation of a series of monoquaternary pyridinium oximes bearing either a heterocyclic side chain or a functionalized aliphatic side chain and the corresponding in vitro evaluation for reactivation of paraoxon-inhibited electric eel acetylcholinesterase (EeAChE) and recombinant human acetylcholinesterase (rHuAChE) are reported. Several newly synthesized compounds efficiently reactivated inhibited EeAChE, but were poor reactivators of inhibited rHuAChE. Compounds bearing a thiophene ring in the side chain (20, 23, 26 and 29) showed better reactivation (24-37% for EeAChE and 5-9% for rHuAChE) compared to compounds with furan and isoxazole heterocycles (0-8% for EeAChE and 2-3% for rHuAChE) at 10(-5)M. The N-pyridyl-CH(2)COOH analog 8 reactivated EeAChE (36%) and rHuAChE (15%) at 10(-4)M with a k(r) value better than 2-pyridine aldoxime methiodide (2-PAM) for rHuAChE.
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Affiliation(s)
- Sandip B Bharate
- NIH COBRE Center for Structural and Functional Neuroscience, Department of Biomedical and Pharmaceutical Sciences, The University of Montana, Missoula, MT 59812, USA
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26
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Kuca K, Cabal J, Jung YS, Musilek K, Soukup O, Jun D, Pohanka M, Musilova L, Karasová J, Novotný L, Hrabinova M. Reactivation of human brain homogenate cholinesterases inhibited by Tabun using newly developed oximes K117 and K127. Basic Clin Pharmacol Toxicol 2009; 105:207-10. [PMID: 19473310 DOI: 10.1111/j.1742-7843.2009.00421.x] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/20/2022]
Abstract
Newly developed acetylcholinesterase reactivators K117 [1,5-bis(4-hydroxyiminomethylpyridinium)-3-oxapentane dichloride] and K127 [(1-(4-hydroxyiminomethylpyridinium)-5-(4-carbamoylpyridinium)-3-oxapentane dibromide)] were tested for their potency to reactivate tabun-inhibited human brain cholinesterases. Pralidoxime and trimedoxime were chosen as standard reference reactivators. Human tissue was used, as that was closer on the real treatment of human beings. As a result, oxime K127 was found as the best tested reactivator according to the constant k(r), characterizing the overall reactivation process. On the contrary, the maximal reactivation ability expressed as percentage of reactivation was the best for trimedoxime. This differences were caused as a result of using the enzyme from different species. Due to this, experiments on human tissue should be conducted after in vitro and in vivo tests on animals to eliminate such important failures of promising oximes.
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Affiliation(s)
- Kamil Kuca
- Center of Advanced Studies, Faculty of Military Health Sciences, University of Defence, 500 01 Hradec Kralove, Czech Republic.
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Kuca K, Cabal J, Jun D, Hrabinova M. Potency of Five Structurally Different Acetylcholinesterase Reactivators to Reactivate Human Brain Cholinesterases Inhibited by Cyclosarin. Clin Toxicol (Phila) 2008; 45:512-5. [PMID: 17503257 DOI: 10.1080/15563650701354234] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/23/2022]
Abstract
Acetylcholinesterase (AChE; EC 3.1.1.7) reactivators are used as a part of the antidotal therapy of organophosphorus pesticide and nerve agent intoxications. Cyclosarin is one member of the nerve agent family. In this article, we compared the reactivation potency of five structurally different AChE reactivators (pralidoxime, trimedoxime, methoxime, HS-6, and BI-6) to reactivate cyclosarin-inhibited cholinesterases of human brain. The results demonstrate that the bisquaternary monooxime reactivator BI-6 seems to be the most potent reactivator of cyclosarin-inhibited cholinesterases. Moreover, according to the results, we can describe basic structural requirements, which are necessary for the efficacious reactivation process.
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Affiliation(s)
- Kamil Kuca
- Department of Toxicology, Faculty of Military Health Sciences, University of Defense, Hradec Kralove.,Czech Republic.
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Musilek K, Kucera J, Jun D, Dohnal V, Opletalova V, Kuca K. Monoquaternary pyridinium salts with modified side chain-synthesis and evaluation on model of tabun- and paraoxon-inhibited acetylcholinesterase. Bioorg Med Chem 2008; 16:8218-23. [PMID: 18676153 DOI: 10.1016/j.bmc.2008.07.036] [Citation(s) in RCA: 17] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/28/2008] [Revised: 07/08/2008] [Accepted: 07/16/2008] [Indexed: 10/21/2022]
Abstract
Acetylcholinesterase reactivators are crucial antidotes for the treatment of organophosphate intoxication. Eighteen monoquaternary reactivators of acetylcholinesterase with modified side chain were developed in an effort to extend the properties of pralidoxime. The known reactivators (pralidoxime, HI-6, obidoxime, trimedoxime, methoxime) and the prepared compounds were tested in vitro on a model of tabun- and paraoxon-inhibited AChE. Monoquaternary reactivators were not able to exceed the best known compounds for tabun poisoning, but some of them did show reactivation better or comparable with pralidoxime for paraoxon poisoning. However, extensive differences were found by a SAR study for various side chains on the non-oxime part of the reactivator molecule.
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Affiliation(s)
- Kamil Musilek
- Department of Toxicology, Faculty of Military Health Sciences, Trebesska 1575, 500 01 Hradec Kralove, Czech Republic.
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Lorke DE, Hasan MY, Arafat K, Kuca K, Musilek K, Schmitt A, Petroianu GA. In vitro oxime protection of human red blood cell acetylcholinesterase inhibited by diisopropyl-fluorophosphate. J Appl Toxicol 2008; 28:422-9. [PMID: 18344198 DOI: 10.1002/jat.1344] [Citation(s) in RCA: 38] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/10/2022]
Abstract
Oximes are enzyme reactivators used in treating poisoning with organophosphorus cholinesterase (AChE) inhibitors. The oxime dose which can be safely administered is limited by the intrinsic toxicity of the substances such as their own AChE-inhibiting tendency. Clinical experience with the available oximes is disappointing. To meet this need, new AChE reactivators of potential clinical utility have been developed. The purpose of the study was to estimate in vitro both the intrinsic toxicity and the extent of possible protection conferred by established (pralidoxime, obidoxime, HI-6, methoxime, trimedoxime) and experimental (K-type) oximes, using diisopropyl-fluoro-phosphate (DFP) as an AChE inhibitor. The IC50 of DFP against human red blood cell AChE was determined ( approximately 120 nm). Measurements were then repeated in the presence of increasing oxime concentrations, leading to an apparent increase in DFP IC50. Calculated IC50 values were plotted against oxime concentrations to obtain an IC50 shift curve. The slope of this shift curve (tan alpha) was used to quantify the magnitude of the protective effect (nm IC50 increase per microm oxime). We show that, in the case of a linear relationship between oxime concentration and IC50, the binding constant K, determined using the Schild equation, equals IC50/DFP/tan alpha. Based on the values of tan alpha and of the binding constant K, some of the new K-oxime reactivators are far superior to pralidoxime (tan alpha = 0.8), obidoxime (1.5), HI-6 (0.8), trimedoxime (2.9) and methoxime (5.9), with K-107 (17), K-108 (20), and K-113 (16) being the outstanding compounds.
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Affiliation(s)
- D E Lorke
- UAE University, Faculty of Medicine and Health Sciences, Al Ain, United Arab Emirates
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Musilek K, Holas O, Kuca K, Jun D, Dohnal V, Opletalova V, Dolezal M. Synthesis of monooxime-monocarbamoyl bispyridinium compounds bearing (E)-but-2-ene linker and evaluation of their reactivation activity against tabun- and paraoxon-inhibited acetylcholinesterase. J Enzyme Inhib Med Chem 2008; 23:70-6. [PMID: 18341256 DOI: 10.1080/14756360701383981] [Citation(s) in RCA: 45] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/22/2022] Open
Abstract
Six AChE monooxime-monocarbamoyl reactivators with an (E)-but-2-ene linker were synthesized using modification of currently known synthetic pathways. Their potency to reactivate AChE inhibited by the nerve agent tabun and insecticide paraoxon was tested in vitro. The reactivation efficacies of pralidoxime, HI-6, obidoxime, K048, K075 and the newly prepared reactivators were compared. According to the results obtained, one reactivator seems to be promising against tabun-inhibited AChE and two reactivators against paraoxon-inhibited AChE. The best results were obtained for bisquaternary substances with at least one oxime group in position four.
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Affiliation(s)
- Kamil Musilek
- Department of Toxicology, Faculty of Military Health Sciences, Hradec Kralove, Czech Republic.
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Musilek K, Jampilek J, Dohnal J, Jun D, Gunn-Moore F, Dolezal M, Kuca K. RP-HPLC determination of the lipophilicity of bispyridinium reactivators of acetylcholinesterase bearing a but-2-ene connecting linker. Anal Bioanal Chem 2008; 391:367-72. [DOI: 10.1007/s00216-008-2018-8] [Citation(s) in RCA: 16] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/17/2007] [Revised: 02/12/2008] [Accepted: 02/21/2008] [Indexed: 11/29/2022]
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Acharya J, Gupta AK, Mazumder A, Dubey DK. In vitro reactivation of sarin inhibited electric eel acetylcholinesterase by bis-pyridinium oximes bearing methoxy ether linkages. Toxicol In Vitro 2008; 22:525-30. [DOI: 10.1016/j.tiv.2007.10.006] [Citation(s) in RCA: 17] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/30/2007] [Revised: 10/04/2007] [Accepted: 10/17/2007] [Indexed: 11/16/2022]
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Kuca K, Cabal J, Jun D, Koleckar V. In Vitro Comparison of Two Most Promising H-Oximes (HI-6 and HLö-7) and Currently Commercially Available Reactivators Pralidoxime and Obidoxime in Reactivation of Cyclosarin-Inhibited Human Cholinesterases. Toxicol Mech Methods 2008; 18:329-33. [DOI: 10.1080/15376510701380323] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/22/2022]
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Musilek K, Holas O, Kuca K, Jun D, Dohnal V, Dolezal M. Synthesis of a novel series of non-symmetrical bispyridinium compounds bearing a xylene linker and evaluation of their reactivation activity against tabun and paraoxon-inhibited acetylcholinesterase. J Enzyme Inhib Med Chem 2007; 22:425-32. [PMID: 17847708 DOI: 10.1080/14756360601164960] [Citation(s) in RCA: 36] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/23/2022] Open
Abstract
Nine potential non-symmetrical xylene-bridged AChE reactivators were synthesized using modifications of currently known synthetic pathways. Their potency to reactivate AChE inhibited by the nerve agent tabun and the insecticide paraoxon together with nine symmetrical xylene-bridged compounds, was tested in vitro. Seven compounds were promising against paraoxon-inhibited AChE. Two compounds were found to be more potent against tabun-inhibited AChE than obidoxime at a concentration applicable in vivo.
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Affiliation(s)
- Kamil Musilek
- Department of Toxicology, Faculty of Military Health Sciences, Trebesska 1575, 500 01 Hradec Kralove, Czech Republic.
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Musilek K, Holas O, Jun D, Dohnal V, Gunn-Moore F, Opletalova V, Dolezal M, Kuca K. Monooxime reactivators of acetylcholinesterase with (E)-but-2-ene linker—Preparation and reactivation of tabun- and paraoxon-inhibited acetylcholinesterase. Bioorg Med Chem 2007; 15:6733-41. [PMID: 17764957 DOI: 10.1016/j.bmc.2007.08.002] [Citation(s) in RCA: 42] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/21/2007] [Revised: 07/27/2007] [Accepted: 08/03/2007] [Indexed: 11/19/2022]
Abstract
Acetylcholinesterase reactivators are crucial antidotes for the treatment of organophosphate intoxication. Fifteen new monooxime reactivators of acetylcholinesterase with a (E)-but-2-ene linker were developed in an effort to extend the properties of K-oxime (E)-1-(4-carbamoylpyridinium)-4-(4-hydroxyiminomethylpyridinium)-but-2-ene dibromide (K203). The known reactivators (pralidoxime, HI-6, obidoxime, K075, K203) and the new compounds were tested in vitro on a model of tabun- and paraoxon-inhibited AChE. Monooxime reactivators were not able to exceed the best known compounds for tabun poisoning, but some of them did show reactivation comparable with known compounds for paraoxon poisoning. However, extensive differences were found by a SAR study for various substitutions on the non-oxime part of the reactivator molecule.
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Affiliation(s)
- Kamil Musilek
- Department of Pharmaceutical Chemistry and Drug Control, Faculty of Pharmacy in Hradec Kralove, Charles University in Prague, Heyrovskeho 1203, 500 05, Hradec Kralove, Czech Republic
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Targeted synthesis of 1-(4-hydroxyiminomethylpyridinium)-3-pyridiniumpropane dibromide--a new nerve agent reactivator. Molecules 2007; 12:1964-72. [PMID: 17960099 DOI: 10.3390/12081964] [Citation(s) in RCA: 14] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/31/2007] [Revised: 08/14/2007] [Accepted: 08/14/2007] [Indexed: 11/17/2022] Open
Abstract
Preparation of 1-(4-hydroxy-iminomethylpyridinium)-3-pyridiniumpropane dibromide is described. This compound represents a new acetylcholinesterase (AChE) reactivator, which has no substituents on the second pyridinium ring as found in other commonly used AChE reactivators. The reactivation ability of this reactivator was tested on tabun- and cyclosarin-inhibited AChE. According to the results obtained, the new compound (without substitution and with decreased molecule size) showed increased reactivation potency in case of cyclosarin inhibited AChE. A potent oxime for treatment of tabun and cyclosarin-caused intoxications was thus obtained via slight modification of the reactivator structure (compared to trimedoxime and K027).
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Musilek K, Kuca K, Dohnal V, Jun D, Marek J, Koleckar V. Two step synthesis of a non-symmetric acetylcholinesterase reactivator. Molecules 2007; 12:1755-61. [PMID: 17960085 PMCID: PMC6149169 DOI: 10.3390/12081755] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/25/2007] [Revised: 08/01/2007] [Accepted: 08/06/2007] [Indexed: 11/16/2022] Open
Abstract
The newly developed and very promising acetylcholinesterase reactivator (E)-1-(2-hydroxyiminomethylpyridinium)-4-(4-hydroxyiminomethylpyridinium)-but-2-ene dibromide was prepared using two different pathways via a two-step synthesis involving the appropriate (E)-1-(4-bromobut-2-enyl)-2- or 4-hydroxyiminomethyl-pyridinium bromides. Afterwards, purities and yields of the desired product prepared by both routes were compared. Finally, its potency to reactivate several nerve agent-inhibited acetylcholinesterases was tested.
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Affiliation(s)
- Kamil Musilek
- Department of Toxicology, Faculty of Military Health Sciences, Trebesska 1575, 500 01 Hradec Kralove, Czech Republic
- Faculty of Pharmacy in Hradec Kralove, Charles University in Prague, Heyrovskeho 1203, 500 05 Hradec Kralove, Czech Republic
| | - Kamil Kuca
- Department of Toxicology, Faculty of Military Health Sciences, Trebesska 1575, 500 01 Hradec Kralove, Czech Republic
- Center of Advanced Studies, Faculty of Military Health Sciences, Trebesska 1575, 500 01 Hradec Kralove, Czech Republic
| | - Vlastimil Dohnal
- Department of Toxicology, Faculty of Military Health Sciences, Trebesska 1575, 500 01 Hradec Kralove, Czech Republic
- Department of Food Technology, Mendel University of Agriculture and Forestry Brno, Zemedelska 1, 613 00 Brno, Czech Republic
| | - Daniel Jun
- Department of Toxicology, Faculty of Military Health Sciences, Trebesska 1575, 500 01 Hradec Kralove, Czech Republic
- Center of Advanced Studies, Faculty of Military Health Sciences, Trebesska 1575, 500 01 Hradec Kralove, Czech Republic
| | - Jan Marek
- Faculty of Pharmacy in Hradec Kralove, Charles University in Prague, Heyrovskeho 1203, 500 05 Hradec Kralove, Czech Republic
| | - Vit Koleckar
- Center of Advanced Studies, Faculty of Military Health Sciences, Trebesska 1575, 500 01 Hradec Kralove, Czech Republic
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Musilek K, Holas O, Kuca K, Jun D, Dohnal V, Opletalova V, Dolezal M. Novel series of bispyridinium compounds bearing a (Z)-but-2-ene linker—Synthesis and evaluation of their reactivation activity against tabun and paraoxon-inhibited acetylcholinesterase. Bioorg Med Chem Lett 2007; 17:3172-6. [PMID: 17383875 DOI: 10.1016/j.bmcl.2007.03.025] [Citation(s) in RCA: 24] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/19/2007] [Revised: 03/07/2007] [Accepted: 03/09/2007] [Indexed: 10/23/2022]
Abstract
Six novel AChE reactivators with a (Z)-but-2-ene linker were synthesized using the known synthetic pathways. Their ability to reactivate AChE, which had been previously inhibited by nerve agent tabun or pesticide paraoxon, was tested in vitro and compared to pralidoxime, HI-6, obidoxime, and K075. The novel synthesized compounds were found to be ineffective against GA-inhibited AChE but the ability of (Z)-1,4-bis(4-hydroxyiminomethylpyridinium)-but-2-ene dibromide to reactivate paraoxon-inhibited AChE was comparable with that of oxime K075. Notably, the oxime group in position four substantially increased the ability of the novel compounds to reactivate paraoxon-inhibited AChE.
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Affiliation(s)
- Kamil Musilek
- Department of Pharmaceutical Chemistry and Drug Control, Faculty of Pharmacy in Hradec Kralove, Charles University in Prague, Heyrovskeho 1203, 500 05 Hradec Kralove, Czech Republic
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Kuca K, Cabal J, Jun D, Musilek K. In vitro reactivation potency of acetylcholinesterase reactivators--K074 and K075--to reactivate tabun-inhibited human brain cholinesterases. Neurotox Res 2007; 11:101-6. [PMID: 17449453 DOI: 10.1007/bf03033389] [Citation(s) in RCA: 12] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/20/2022]
Abstract
In this work, two oximes for the treatment of tabun-inhibited acetylcholinesterase (AChE; EC 3.1.1.7), K074 (1,4-bis(4-hydroxyiminomethylpyridinium)butane dibromide) and K075 ((E)-1,4-bis(4-hydroxyiminomethylpyridinium)but-2-en dibromide), were tested in vitro as reactivators of AChE. Comparison was made with currently used AChE reactivators (pralidoxime, HI-6, methoxime and obidoxime). Human brain homogenate was taken as an appropriate source of the cholinesterases. As resulted, oxime K074 appears to be the most potent reactivator of tabun-inhibited AChE, with reactivation potency comparable to that of obidoxime. A second AChE reactivator, K075, does not attain as great a reactivation potency as K074, although its maximal reactivation (17%) was achieved at relevant concentrations for humans.
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Affiliation(s)
- Kamil Kuca
- Centre of Advanced Studies, and Department of Toxicology, Faculty of Military Health Sciences, University of Defense, Trebesska 1575, 500 01 Hradec Kralove, Czech Republic.
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Musílek K, Kuča K, Jun D, Doležal M. In vitro reactivation potency of bispyridinium (E)-but-2-ene linked acetylcholinesterase reactivators against tabun-inhibited acetylcholinesterase. J Appl Biomed 2007. [DOI: 10.32725/jab.2007.004] [Citation(s) in RCA: 15] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/05/2022] Open
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Abstract
The use of organophosphorus pesticides results in toxicity risk to non-target organisms. Organophosphorus compounds share a common mode of action, exerting their toxic effects primarily via acetylcholinesterase (AChE) inhibition. Consequently, acetylcholine accumulates in the synaptic clefts of muscles and nerves, leading to overstimulation of cholinergic receptors. Acute cholinergic crisis immediately follows exposure to organophosphate and includes signs and symptoms resulting from hyperstimulation of central and peripheral muscarinic and nicotinic receptors. The current view of the treatment of organophosphate poisoning includes three strategies, i.e. the use of an anticholinergic drug (e.g., atropine), cholinesterase-reactivating agents (e.g., oximes) and anticonvulsant drugs (e.g., benzodiazepines). Oximes, as a part of antidotal therapy, ensure the recovery of phosphylated enzymes via a process denoted as reactivation of inhibited AChE. However, both experimental results and clinical findings have demonstrated that different oximes are not equally effective against poisonings caused by structurally different organophosphorus compounds. Therefore, antidotal characteristics of conventionally used oximes can be evaluated regarding how close the certain substance is to the theoretical concept of the universal oxime. Pralidoxime (PAM-2), trimedoxime (TMB-4), obidoxime (LüH-6), HI-6 and HLö-7 have all been demonstrated to be very effective in experimental poisonings with sarin and VX. TMB-4 and LüH-6 may reactivate tabun-inhibited AChE, whereas HI-6 possesses the ability to reactivate the soman-inhibited enzyme. An oxime HLö-7 seems to be an efficient reactivator of AChE inhibited by any of the four organophosphorus warfare agents. According to the available literature, the oximes LüH-6 and TMB-4, although relatively toxic, are the most potent to induce reactivation of AChE inhibited by the majority of organophosphorus pesticides. Since there are no reports of controlled clinical trials on the use of TMB-4 in human organophosphate pesticide poisoning, LüH-6 may be a better option.
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Affiliation(s)
- Biljana Antonijevic
- Institute of Toxicological Chemistry, Faculty of Pharmacy, University of Belgrade, Vojvode Stepe 450, 11221 Belgrade, Serbia.
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Worek F, Eyer P, Aurbek N, Szinicz L, Thiermann H. Recent advances in evaluation of oxime efficacy in nerve agent poisoning by in vitro analysis. Toxicol Appl Pharmacol 2007; 219:226-34. [DOI: 10.1016/j.taap.2006.10.001] [Citation(s) in RCA: 84] [Impact Index Per Article: 4.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/20/2006] [Revised: 09/30/2006] [Accepted: 10/02/2006] [Indexed: 10/24/2022]
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Structure—activity relationships for in vitro oxime reactivation of chlorpyrifos-inhibited acetylcholinesterase. CHEMICAL PAPERS 2007. [DOI: 10.2478/s11696-007-0030-7] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/20/2022]
Abstract
AbstractOrganophosphorus pesticides parathion, chlorpyrifos, and malathion inhibit the enzyme acetylcholinesterase (AChE; EC 3.1.1.7) via phosphorylation of its active site. AChE reactivators and anticholinergics are compounds used as antidotes in the case of intoxication by these AChE inhibitors. In this work, chlorpyrifos, a representative member of this pesticide family, was used to inhibit the AChE activity of rat brain. The effect of twenty-one structurally different AChE reactivators was tested in vitro and subsequently, the relationship between their chemical structure and biological activity was outlined.
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Musilek K, Holas O, Kuca K, Jun D, Dohnal V, Dolezal M. Synthesis of asymmetrical bispyridinium compounds bearing cyano-moiety and evaluation of their reactivation activity against tabun and paraoxon-inhibited acetylcholinesterase. Bioorg Med Chem Lett 2006; 16:5673-6. [PMID: 16934462 DOI: 10.1016/j.bmcl.2006.08.011] [Citation(s) in RCA: 18] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/27/2006] [Revised: 07/31/2006] [Accepted: 08/01/2006] [Indexed: 10/24/2022]
Abstract
Three asymmetrical AChE reactivators with cyano-moiety and propane linker were synthesized using modification of currently known synthetic pathways. Their potency to reactivate AChE inhibited by nerve agent tabun and insecticide paraoxon was tested in vitro and compared to pralidoxime, HI-6, obidoxime, K027, and K048. According to the results, three compounds seem to be promising against paraoxon-inhibited AChE. Better results were obtained for bisquaternary substances at least with one oxime group in position four. None of tested substances was able to satisfactorily reactivate tabun-inhibited AChE at concentration applicable for in vivo experiments.
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Affiliation(s)
- Kamil Musilek
- Department of Pharmaceutical Chemistry and Drug Control, Faculty of Pharmacy in Hradec Kralove, Charles University in Prague, Heyrovskeho 1203, 50005 Hradec Kralove, Czech Republic
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Potency of Several Structurally Different Acetylcholinesterase Reactivators to Reactivate House Fly and Bovine Acetylcholinesterases Inhibited by Paraoxon and DFP. B KOREAN CHEM SOC 2006. [DOI: 10.5012/bkcs.2006.27.9.1401] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022]
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Oh KA, Yang GY, Jun D, Kuca K, Jung YS. Bis-pyridiumaldoxime reactivators connected with CH2O(CH2)n OCH2 linkers between pyridinium rings and their reactivity against VX. Bioorg Med Chem Lett 2006; 16:4852-5. [PMID: 16828550 DOI: 10.1016/j.bmcl.2006.06.063] [Citation(s) in RCA: 14] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/17/2006] [Revised: 06/12/2006] [Accepted: 06/17/2006] [Indexed: 10/24/2022]
Abstract
New bis-pyridinium oxime reactivators connected with CH2O(CH2)n OCH2 linkers between two pyridinium rings were designed and synthesized, and their reactivation potency was evaluated for AChE inhibited by organophosphorus VX agent. Among the prepared compounds, 1,2-dimethoxy-ethylene-bis-N,N'-4-pyridiumaldoxime dichloride 5a was the most potent and appeared to be the most promising compound as a potential reactivator for AChE inhibited by organophosphorus VX agent.
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Affiliation(s)
- Kyung-Ae Oh
- Medicinal Science Division, Korea Research Institute of Chemical Technology, PO Box 107, Yusong, Taejon 305-606, Republic of Korea
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