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Chen L, Hu B, Wang H, Li W, Wang S, Luan J, Liu H, Wang J, Cheng M. Selectivity mechanism of muscarinic acetylcholine receptor antagonism through in silico investigation. Phys Chem Chem Phys 2022; 24:26269-26287. [PMID: 36281693 DOI: 10.1039/d2cp02972c] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 06/16/2023]
Abstract
Structures of muscarinic acetylcholine receptors illustrate the strikingly high degree of homology of the residues among isoforms, thus leading to difficulty in achieving subtype selectivity when targeting these receptors and causing undesired side effects when treating the corresponding diseases. Considering the urgent need for more selective and potency therapies, this study is aimed at revealing the selectivity mechanism against M4/5 via in silico strategies, revealing crucial molecular interactions such as hydrogen bonds and pi-cation interaction formed between the key residues TYR416, ASN417, and TRP435 of M4, respectively, hydrophobic pocket formed by the key residues, especially CYS484 of M5. Besides, the water around TYR416M4 and ASN459M5, which can be replaced by substituent groups which can form the hydrogen bond interaction network by simulated bridging water and the water around ASP112M4, whose replacement maybe not contribute to the increase in binding affinity of the compound, may affect the inhibitory selectivity among M4/5 in the aspect of the solvent. Moreover, from the point of inhibitors, compounds with a positively ionizable group could selectively bind to M4 receptors, while hydrophobic molecules may bind preferably to M5. We believe that the current study would provide a basis for the design of subsequent M4/5 selective antagonists.
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Affiliation(s)
- Lu Chen
- Key Laboratory of Structure-Based Drug Design & Discovery of Ministry of Education, Shenyang Pharmaceutical University, Shenyang 110016, People's Republic of China.
- Key Laboratory of Intelligent Drug Design and New Drug Discovery of Liaoning Province, Shenyang Pharmaceutical University, Shenyang 110016, China
- School of Pharmaceutical Engineering, Shenyang Pharmaceutical University, Shenyang 110016, People's Republic of China
| | - Baichun Hu
- Key Laboratory of Structure-Based Drug Design & Discovery of Ministry of Education, Shenyang Pharmaceutical University, Shenyang 110016, People's Republic of China.
- Key Laboratory of Intelligent Drug Design and New Drug Discovery of Liaoning Province, Shenyang Pharmaceutical University, Shenyang 110016, China
- School of Pharmaceutical Engineering, Shenyang Pharmaceutical University, Shenyang 110016, People's Republic of China
| | - Hanxun Wang
- Key Laboratory of Structure-Based Drug Design & Discovery of Ministry of Education, Shenyang Pharmaceutical University, Shenyang 110016, People's Republic of China.
- Key Laboratory of Intelligent Drug Design and New Drug Discovery of Liaoning Province, Shenyang Pharmaceutical University, Shenyang 110016, China
- School of Pharmaceutical Engineering, Shenyang Pharmaceutical University, Shenyang 110016, People's Republic of China
| | - Weixia Li
- Key Laboratory of Structure-Based Drug Design & Discovery of Ministry of Education, Shenyang Pharmaceutical University, Shenyang 110016, People's Republic of China.
- Key Laboratory of Intelligent Drug Design and New Drug Discovery of Liaoning Province, Shenyang Pharmaceutical University, Shenyang 110016, China
- School of Pharmaceutical Engineering, Shenyang Pharmaceutical University, Shenyang 110016, People's Republic of China
| | - Shizun Wang
- Key Laboratory of Structure-Based Drug Design & Discovery of Ministry of Education, Shenyang Pharmaceutical University, Shenyang 110016, People's Republic of China.
- Key Laboratory of Intelligent Drug Design and New Drug Discovery of Liaoning Province, Shenyang Pharmaceutical University, Shenyang 110016, China
- School of Pharmaceutical Engineering, Shenyang Pharmaceutical University, Shenyang 110016, People's Republic of China
| | - Jiasi Luan
- Key Laboratory of Structure-Based Drug Design & Discovery of Ministry of Education, Shenyang Pharmaceutical University, Shenyang 110016, People's Republic of China.
- Key Laboratory of Intelligent Drug Design and New Drug Discovery of Liaoning Province, Shenyang Pharmaceutical University, Shenyang 110016, China
- School of Medical Devices, Shenyang Pharmaceutical University, Shenyang 110016, People's Republic of China
| | - Haihan Liu
- Key Laboratory of Structure-Based Drug Design & Discovery of Ministry of Education, Shenyang Pharmaceutical University, Shenyang 110016, People's Republic of China.
- Key Laboratory of Intelligent Drug Design and New Drug Discovery of Liaoning Province, Shenyang Pharmaceutical University, Shenyang 110016, China
- School of Pharmaceutical Engineering, Shenyang Pharmaceutical University, Shenyang 110016, People's Republic of China
| | - Jian Wang
- Key Laboratory of Structure-Based Drug Design & Discovery of Ministry of Education, Shenyang Pharmaceutical University, Shenyang 110016, People's Republic of China.
- Key Laboratory of Intelligent Drug Design and New Drug Discovery of Liaoning Province, Shenyang Pharmaceutical University, Shenyang 110016, China
- School of Pharmaceutical Engineering, Shenyang Pharmaceutical University, Shenyang 110016, People's Republic of China
| | - Maosheng Cheng
- Key Laboratory of Structure-Based Drug Design & Discovery of Ministry of Education, Shenyang Pharmaceutical University, Shenyang 110016, People's Republic of China.
- Key Laboratory of Intelligent Drug Design and New Drug Discovery of Liaoning Province, Shenyang Pharmaceutical University, Shenyang 110016, China
- School of Pharmaceutical Engineering, Shenyang Pharmaceutical University, Shenyang 110016, People's Republic of China
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Amend N, Niessen KV, Seeger T, Wille T, Worek F, Thiermann H. Diagnostics and treatment of nerve agent poisoning—current status and future developments. Ann N Y Acad Sci 2020; 1479:13-28. [DOI: 10.1111/nyas.14336] [Citation(s) in RCA: 16] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/17/2020] [Revised: 02/25/2020] [Accepted: 03/05/2020] [Indexed: 12/20/2022]
Affiliation(s)
- Niko Amend
- Bundeswehr Institute of Pharmacology and Toxicology Munich Germany
| | - Karin V. Niessen
- Bundeswehr Institute of Pharmacology and Toxicology Munich Germany
| | - Thomas Seeger
- Bundeswehr Institute of Pharmacology and Toxicology Munich Germany
| | - Timo Wille
- Bundeswehr Institute of Pharmacology and Toxicology Munich Germany
| | - Franz Worek
- Bundeswehr Institute of Pharmacology and Toxicology Munich Germany
| | - Horst Thiermann
- Bundeswehr Institute of Pharmacology and Toxicology Munich Germany
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Marquart K, Prokopchuk O, Wilhelm D, Worek F, Thiermann H, Martignoni ME, Wille T. Human small bowel as model for poisoning with organophosphorus compounds. Toxicol In Vitro 2019; 57:76-80. [DOI: 10.1016/j.tiv.2019.02.010] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/07/2018] [Revised: 01/21/2019] [Accepted: 02/09/2019] [Indexed: 11/26/2022]
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Kassa J, Timperley CM, Bird M, Williams RL, Green AC, Tattersall JEH. Some benefit from non-oximes MB408, MB442 and MB444 in combination with the oximes HI-6 or obidoxime and atropine in antidoting sarin or cyclosarin poisoned mice. Toxicology 2018; 408:95-100. [PMID: 30005893 DOI: 10.1016/j.tox.2018.07.008] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/12/2018] [Revised: 06/27/2018] [Accepted: 07/09/2018] [Indexed: 11/15/2022]
Abstract
The effect of three newly developed bispyridinium non-oxime compounds (MB408, MB442, and MB444) on the therapeutic efficacy of a standard antidotal treatment (atropine in combination with the oxime HI-6 or obidoxime) of acute poisoning by two nerve agents (sarin and cyclosarin) in mice was studied. The therapeutic efficacy of atropine in combination with an oxime with or without one of the bispyridinium non-oximes was evaluated by determination of the 24 h LD50 values of the nerve agents studied and by measurement of the survival time after supralethal poisoning. Addition of all tested non-oximes increased the therapeutic efficacy of atropine in combination with an oxime against sarin poisoning; however, the differences were not significant. The non-oximes also positively influenced the number of surviving mice 6 h after supralethal poisoning with sarin. In the case of cyclosarin, they were also slightly beneficial in the treatment of acute poisoning. The higher dose of MB444 was able to significantly increase the therapeutic efficacy of standard antidotal treatment of poisoning with cyclosarin. The benefit of each bispyridinium non-oxime compound itself was obviously dose-dependent. In summary, the addition of MB compounds to the standard antidotal treatment of acute nerve agent poisoning was beneficial for the antidotal treatment of sarin or cyclosarin poisoning, although their benefit at 24 h after poisoning was not significant, with the exception of the higher dose of MB444 against cyclosarin.
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Affiliation(s)
- Jiri Kassa
- Department of Toxicology and Military Pharmacy, Faculty of Military Health Sciences, Trebesska 1575, 500 01 Hradec Kralove, Czech Republic.
| | - Christopher M Timperley
- Chemical, Biological and Radiological Division, Defence Science and Technology Laboratory (Dstl), Porton Down, Salisbury SP4 0JQ, United Kingdom
| | - Mike Bird
- Chemical, Biological and Radiological Division, Defence Science and Technology Laboratory (Dstl), Porton Down, Salisbury SP4 0JQ, United Kingdom
| | - Rebecca L Williams
- Chemical, Biological and Radiological Division, Defence Science and Technology Laboratory (Dstl), Porton Down, Salisbury SP4 0JQ, United Kingdom
| | - A Christopher Green
- Chemical, Biological and Radiological Division, Defence Science and Technology Laboratory (Dstl), Porton Down, Salisbury SP4 0JQ, United Kingdom
| | - John E H Tattersall
- Chemical, Biological and Radiological Division, Defence Science and Technology Laboratory (Dstl), Porton Down, Salisbury SP4 0JQ, United Kingdom
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Marquart K, Prokopchuk O, Worek F, Thiermann H, Martignoni ME, Wille T. Human small bowel as a useful tool to investigate smooth muscle effects of potential therapeutics in organophosphate poisoning. Toxicol Lett 2018; 293:235-240. [PMID: 29154801 DOI: 10.1016/j.toxlet.2017.11.012] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/29/2017] [Revised: 11/07/2017] [Accepted: 11/12/2017] [Indexed: 11/29/2022]
Abstract
Isolated organs proofed to be a robust tool to study effects of (potential) therapeutics in organophosphate poisoning. Small bowel samples have been successfully used to reveal smooth muscle relaxing effects. In the present study, the effects of obidoxime, TMB-4, HI-6 and MB 327 were investigated on human small bowel tissue and compared with rat data. Hereby, the substances were tested in at least seven different concentrations in the jejunum or ileum both pre-contracted with carbamoylcholine. Additionally, the cholinesterase activity of native tissue was determined. Human small intestine specimens showed classical dose response-curves, similar to rat tissue, with MB 327 exerting the most potent smooth muscle relaxant effect in both species (human EC50=0.7×10-5M and rat EC50=0.7×10-5M). The AChE activity for human and rat samples did not differ significantly (rat jejunum=1351±166 mU/mg wet weight; rat ileum=1078±123 mU/mg wet weight; human jejunum=1030±258 mU/mg wet weight; human ileum=1293±243 mU/mg wet weight). Summarizing, our isolated small bowel setup seems to be a solid tool to investigate the effects of (potential) therapeutics on pre-contracted smooth muscle, with data being transferable between rat and humans.
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Affiliation(s)
- Katharina Marquart
- Bundeswehr Institute of Pharmacology and Toxicology, Neuherbergstr. 11, 80397 Munich, Germany
| | - Olga Prokopchuk
- Technical University of Munich, School of Medicine, Department of Surgery, Ismaninger Str. 22, 81675 Munich, Germany
| | - Franz Worek
- Bundeswehr Institute of Pharmacology and Toxicology, Neuherbergstr. 11, 80397 Munich, Germany
| | - Horst Thiermann
- Bundeswehr Institute of Pharmacology and Toxicology, Neuherbergstr. 11, 80397 Munich, Germany
| | - Marc E Martignoni
- Technical University of Munich, School of Medicine, Department of Surgery, Ismaninger Str. 22, 81675 Munich, Germany
| | - Timo Wille
- Bundeswehr Institute of Pharmacology and Toxicology, Neuherbergstr. 11, 80397 Munich, Germany.
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Kassa J, Timperley CM, Bird M, Williams RL, Green AC, Tattersall JEH. Evaluation of the Influence of Three Newly Developed Bispyridinium Anti-nicotinic Compounds (MB408, MB442, MB444) on the Efficacy of Antidotal Treatment of Nerve Agent Poisoning in Mice. Basic Clin Pharmacol Toxicol 2017; 122:429-435. [PMID: 29117635 DOI: 10.1111/bcpt.12935] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/14/2017] [Accepted: 10/26/2017] [Indexed: 11/28/2022]
Abstract
The influence of three newly developed bispyridinium antinicotinic compounds (the non-oximes MB408, MB442 and MB444) on the therapeutic efficacy of a standard antidotal treatment (atropine in combination with an oxime) of acute poisoning by the organophosphorus nerve agents tabun and soman was studied in mice. The therapeutic efficacy of atropine in combination with an oxime with or without one of the bispyridinium non-oximes was evaluated by determination of the LD50 values of the nerve agents and measurement of the survival time after supralethal poisoning. Addition of all the tested non-oximes increased significantly the therapeutic efficacy of atropine in combination with an oxime against tabun poisoning. They also positively influenced the number of surviving mice 6 hr after supralethal poisoning with tabun. However, they were only slightly effective for the treatment of soman poisoning. The benefit of the tested bispyridinium non-oximes was dose-dependent. To conclude, the addition of bispyridinium non-oximes to the standard antidotal treatment of acute poisoning with tabun was beneficial regardless of the chosen non-oxime, but only slightly beneficial in the case of soman poisoning.
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Affiliation(s)
- Jiri Kassa
- Department of Toxicology and Military Pharmacy, Faculty of Military Health Sciences, Hradec Kralove, Czech Republic
| | - Christopher M Timperley
- Chemical, Biological and Radiological Division, Defence Science and Technology Laboratory (Dstl), Porton Down, Salisbury, UK
| | - Mike Bird
- Chemical, Biological and Radiological Division, Defence Science and Technology Laboratory (Dstl), Porton Down, Salisbury, UK
| | - Rebecca L Williams
- Chemical, Biological and Radiological Division, Defence Science and Technology Laboratory (Dstl), Porton Down, Salisbury, UK
| | - A Christopher Green
- Chemical, Biological and Radiological Division, Defence Science and Technology Laboratory (Dstl), Porton Down, Salisbury, UK
| | - John E H Tattersall
- Chemical, Biological and Radiological Division, Defence Science and Technology Laboratory (Dstl), Porton Down, Salisbury, UK
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Neumaier K, Worek F, Thiermann H, Wille T. Bispyridinium non-oximes: An evaluation of cardiac effects in isolated hearts and smooth muscle relaxing effects in jejunum. Toxicol In Vitro 2016; 35:11-6. [DOI: 10.1016/j.tiv.2016.05.005] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/28/2016] [Revised: 05/10/2016] [Accepted: 05/11/2016] [Indexed: 10/21/2022]
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Kassa J, Pohanka M, Timperley CM, Bird M, Green AC, Tattersall JEH. Evaluation of the benefit of the bispyridinium compound MB327 for the antidotal treatment of nerve agent-poisoned mice. Toxicol Mech Methods 2016; 26:334-9. [DOI: 10.3109/15376516.2016.1162249] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/13/2022]
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Price ME, Docx CJ, Rice H, Fairhall SJ, Poole SJ, Bird M, Whiley L, Flint DP, Green AC, Timperley CM, Tattersall JE. Pharmacokinetic profile and quantitation of protection against soman poisoning by the antinicotinic compound MB327 in the guinea-pig. Toxicol Lett 2016; 244:154-60. [DOI: 10.1016/j.toxlet.2015.08.013] [Citation(s) in RCA: 20] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/06/2015] [Revised: 07/24/2015] [Accepted: 08/10/2015] [Indexed: 11/20/2022]
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John H, Mikler J, Worek F, Thiermann H. Reversed-phase ion-pair chromatography-diode array detection of the bispyridinium compound MB327: plasma analysis of a potential novel antidote for the treatment of organophosphorus poisoning. Drug Test Anal 2015; 8:154-63. [PMID: 26041012 DOI: 10.1002/dta.1821] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/25/2015] [Revised: 05/12/2015] [Accepted: 05/12/2015] [Indexed: 11/08/2022]
Abstract
In the case of poisoning by organophosphorus nerve agents or pesticides, there is still a lack of pharmacological treatment of the cholinergic crisis selectively targeting the nicotinic acetylcholine receptor. Recently, the compound MB327 was identified as a potential novel lead structure to close this gap, thus demanding a quantitative assay for initial pharmacokinetic (PK) studies. MB327 is a salt consisting of the dicationic bispyridinium compound (BPC) 1,1´-(propane-1,3-diyl)bis(4-tert-butylpyridinium) and two iodide counter ions. Due to the permanent positive charge of the BPC, an isocratic reversed-phase ion-pair chromatographic separation (RPIPC) was developed using heptanesulfonic acid as ion-pairing reagent and 45% v/v methanol as organic modifier (1 mL/min). Selective UV-detection (230 nm) was done by a diode array detector (DAD) for reliable, rugged, precise (RSD < 7%) and accurate (96-104%) quantitative analysis of 50 μL swine plasma (linear range 1-1000 µg BPC/mL plasma, lower limit of quantification 2 µg/mL). During method validation, diverse parameters essential for the chromatographic process were investigated to generate van´t Hoff, van Deemter and width plots allowing calculation of thermodynamic data like the distribution constant K (5.7 ± 0.3), change in enthalpy, ΔH(0) : -23.66 kJ/mol, and entropy, ΔS(0) : -65 J/(mol*K). In addition, RPIPC-DAD analysis enabled calculation of molar absorptivities of the BPC, ε230 : 17 400 ± 1100 L/(mol*cm), and iodide, ε230 : 9900 ± 400 L/(mol*cm), which determination was hampered by interference with each other in conventional cuvette UV-spectrophotometric measurements. Finally, the RPIPC-DAD procedure was applied to samples from an in vivo study of swine.
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Affiliation(s)
- Harald John
- Bundeswehr Institute of Pharmacology and Toxicology, Munich, Germany
| | - John Mikler
- Defence Research and Development Canada-Suffield Research Station, Medicine Hat, Alberta, Canada
| | - Franz Worek
- Bundeswehr Institute of Pharmacology and Toxicology, Munich, Germany
| | - Horst Thiermann
- Bundeswehr Institute of Pharmacology and Toxicology, Munich, Germany
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Niessen K, Seeger T, Tattersall J, Timperley C, Bird M, Green C, Thiermann H, Worek F. Affinities of bispyridinium non-oxime compounds to [3H]epibatidine binding sites of Torpedo californica nicotinic acetylcholine receptors depend on linker length. Chem Biol Interact 2013; 206:545-54. [DOI: 10.1016/j.cbi.2013.10.012] [Citation(s) in RCA: 20] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/06/2013] [Revised: 10/07/2013] [Accepted: 10/07/2013] [Indexed: 01/20/2023]
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Abstract
INTRODUCTION The continuous application of organophosphate pesticides in developing countries, in addition to the remaining stock piles of chemical warfare nerve agents and their possible use is a significant threat to the public. Yet, today's options for a treatment of organophosphorus poisonings are still inadequate. AREAS COVERED This article provides a concise overview of current and future research trying to improve both prophylaxis and treatment of organophosphorus intoxications. The authors provide a summary of current oxime therapy and highlight several new concepts to overcome existing gaps. This overview of therapeutic options is accompanied by two sections on cyclodextrins, related compounds and bioscavengers, which may be used for either prophylaxis or treatment. For both groups, the authors review current drug design and screening approaches, the resulting developments and future challenges. EXPERT OPINION While the search for one multipotent oxime has been a fruitless endeavor, combination of multiple oximes with complemental and systemic reactivity appears as a valuable concept. Development of potential scavengers, be it cyclodextrins or bioscavengers, is still hampered by insufficient efficacy of these compounds. Future strategies will aim at improving their catalytic efficacy while minimizing immunogenicity.
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Affiliation(s)
- Paul Wilhelm Elsinghorst
- Bundeswehr Institute of Pharmacology and Toxicology , Neuherbergstraße 11, D-80937 München , Germany +49 89 3168 2305 ; +49 89 3168 2333 ;
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Thiermann H, Worek F, Kehe K. Limitations and challenges in treatment of acute chemical warfare agent poisoning. Chem Biol Interact 2013; 206:435-43. [PMID: 24091052 DOI: 10.1016/j.cbi.2013.09.015] [Citation(s) in RCA: 115] [Impact Index Per Article: 10.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/02/2013] [Revised: 09/18/2013] [Accepted: 09/20/2013] [Indexed: 02/02/2023]
Abstract
Recent news from Syria on a possible use of chemical warfare agents made the headlines. Furthermore, the motivation of terrorists to cause maximal harm shifts these agents into the public focus. For incidents with mass casualties appropriate medical countermeasures must be available. At present, the most important threats arise from nerve agents and sulfur mustard. At first, self-protection and protection of medical units from contamination is of utmost importance. Volatile nerve agent exposure, e.g. sarin, results in fast development of cholinergic crisis. Immediate clinical diagnosis can be confirmed on-site by assessment of acetylcholinesterase activity. Treatment with autoinjectors that are filled with 2mg atropine and an oxime (at present obidoxime, pralidoxime, TMB-4 or HI-6) are not effective against all nerve agents. A more aggressive atropinisation has to be considered and more effective oximes (if possible with a broad spectrum or a combination of different oximes) as well as alternative strategies to cope with high acetylcholine levels at synaptic sites should be developed. A further gap exists for the treatment of patients with sustained cholinergic crisis that has to be expected after exposure to persistent nerve agents, e.g. VX. The requirement for long-lasting artificial ventilation can be reduced with an oxime therapy that is optimized by using the cholinesterase status for guidance or by measures (e.g. scavengers) that are able to reduce the poison load substantially in the patients. For sulfur mustard poisoning no specific antidote is available until now. Symptomatic measures as used for treatment of burns are recommended together with surgical or laser debridement. Thus, huge amounts of resources are expected to be consumed as wound healing is impaired. Possible depots of sulfur mustard in tissues may aggravate the situation. More basic knowledge is necessary to improve substantially therapeutic options. The use of stem cells may provide a new and promising option.
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Affiliation(s)
- Horst Thiermann
- Bundeswehr Institute of Pharmacology and Toxicology, Munich, Germany.
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Königer C, Worek F, Thiermann H, Wille T. Effect of MB327 and oximes on rat intestinal smooth muscle function. Chem Biol Interact 2013; 204:1-5. [PMID: 23603452 DOI: 10.1016/j.cbi.2013.04.004] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/14/2012] [Revised: 03/20/2013] [Accepted: 04/09/2013] [Indexed: 10/26/2022]
Abstract
Organophosphorous compounds (OP) are highly toxic compounds. Great efforts have been undertaken in the last decades to develop new reactivators of OP-inhibited acetylcholinesterase. So far, a broad-spectrum oxime bearing efficacy against all OP is still missing and alternative approaches are presently under investigation. Previous experiments demonstrated that the bispyridinium non-oxime MB327 was able to improve OP-impaired muscle force in human, rat and guinea pig respiratory muscles and to increase survival in soman, sarin and tabun poisoned guinea pigs. Recent studies indicate that MB327 exhibits a high affinity to muscarinic acetylcholine receptors but up to now, only scarce information is available on the effects of MB327 in isolated organs. Now, the antimuscarinic effect of MB327 was compared to that of established oximes and atropine in a rat jejunum smooth muscle model. MB327 showed a fully reversible smooth muscle relaxing effect at lower concentrations (EC₅₀≈ 6 μM) than all tested oximes. In fact, MB327 exhibited an antimuscarinic smooth muscle relaxing effect at concentrations which were shown to improve OP-impaired skeletal muscle force. Hence, it may be assumed that the antimuscarinic potency of MB327 may contribute to its therapeutic effect in OP poisoning.
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Affiliation(s)
- C Königer
- Bundeswehr Institute of Pharmacology and Toxicology, Neuherbergstraße 11, 80937 Munich, Germany
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John H, Blum MM. Editorial: Analysis of drugs for the therapy of anticholinesterase poisoning. Drug Test Anal 2012; 4:167-8. [DOI: 10.1002/dta.412] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/05/2022]
Affiliation(s)
- Harald John
- Bundeswehr Institute of Pharmacology and Toxicology; Munich; Germany
| | - Marc-Michael Blum
- Los Alamos National Laboratory; Bioscience Division; Los Alamos; NM; USA; LA-UR 12-00299
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