1
|
Pampalakis G, Kostoudi S. Chemical, Physical, and Toxicological Properties of V-Agents. Int J Mol Sci 2023; 24:ijms24108600. [PMID: 37239944 DOI: 10.3390/ijms24108600] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/12/2023] [Revised: 05/07/2023] [Accepted: 05/09/2023] [Indexed: 05/28/2023] Open
Abstract
V-agents are exceedingly toxic organophosphate nerve agents. The most widely known V-agents are the phosphonylated thiocholines VX and VR. Nonetheless, other V-subclasses have been synthesized. Here, a holistic overview of V-agents is provided, where these compounds have been categorized based on their structures to facilitate their study. A total of seven subclasses of V-agents have been identified, including phospho(n/r)ylated selenocholines and non-sulfur-containing agents, such as VP and EA-1576 (EA: Edgewood Arsenal). Certain V-agents have been designed through the conversion of phosphorylated pesticides to their respective phosphonylated analogs, such as EA-1576 derived from mevinphos. Further, this review provides a description of their production, physical properties, toxicity, and stability during storage. Importantly, V-agents constitute a percutaneous hazard, while their high stability ensures the contamination of the exposed area for weeks. The danger of V-agents was highlighted in the 1968 VX accident in Utah. Until now, VX has been used in limited cases of terrorist attacks and assassinations, but there is an increased concern about potential terrorist production and use. For this reason, studying the chemistry of VX and other less-studied V-agents is important to understand their properties and develop potential countermeasures.
Collapse
Affiliation(s)
- Georgios Pampalakis
- Laboratory of Pharmacology, School of Pharmacy, Aristotle University of Thessaloniki, 54124 Thessaloniki, Greece
| | - Stavroula Kostoudi
- Laboratory of Pharmacology, School of Pharmacy, Aristotle University of Thessaloniki, 54124 Thessaloniki, Greece
| |
Collapse
|
2
|
Bajgar J, Kuca K, Kassa J. Inhibition of cholinesterases following percutaneous intoxication with V agents in rats. TOXIN REV 2021. [DOI: 10.1080/15569543.2018.1564773] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/26/2022]
Affiliation(s)
- Jiri Bajgar
- Department of Chemistry Faculty of Science, University of Hradec Kralove, Hradec Kralove, Czech Republic
- Biomedical Research Center, University Hospital Hradec Kralove, Hradec Kralove, Czech Republic
| | - Kamil Kuca
- Department of Chemistry Faculty of Science, University of Hradec Kralove, Hradec Kralove, Czech Republic
- Biomedical Research Center, University Hospital Hradec Kralove, Hradec Kralove, Czech Republic
| | - Jiri Kassa
- Department of Toxicology and Military Pharmacy Faculty of Military Health Sciences, University of Defence, Hradec Kralove, Czech Republic
| |
Collapse
|
3
|
Efficient detoxification of nerve agents by oxime-assisted reactivation of acetylcholinesterase mutants. Neuropharmacology 2020; 171:108111. [PMID: 32333945 DOI: 10.1016/j.neuropharm.2020.108111] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/28/2020] [Revised: 03/31/2020] [Accepted: 04/16/2020] [Indexed: 01/06/2023]
Abstract
The recent advancements in crystallography and kinetics studies involving reactivation mechanism of acetylcholinesterase (AChE) inhibited by nerve agents have enabled a new paradigm in the search for potent medical countermeasures in case of nerve agents exposure. Poisonings by organophosphorus compounds (OP) that lead to life-threatening toxic manifestations require immediate treatment that combines administration of anticholinergic drugs and an aldoxime as a reactivator of AChE. An alternative approach to reduce the in vivo toxicity of OP centers on the use of bioscavengers against the parent organophosphate. Our recent research showed that site-directed mutagenesis of AChE can enable aldoximes to substantially accelerate the reactivation of OP-enzyme conjugates while dramatically slowing down rates of OP-conjugate dealkylation (aging). Therefore, this review focuses on oxime-assisted catalysis by AChE mutants that provides a potential means for degradation of organophosphates in the plasma before reaching the cellular target site. This article is part of the special issue entitled 'Acetylcholinesterase Inhibitors: From Bench to Bedside to Battlefield'.
Collapse
|
4
|
Souza FD, Rodrigues Garcia D, Cuya T, Pimentel AS, Gonçalves ADS, Alencastro RBD, França TCC. Molecular Modeling Study of Uncharged Oximes Compared to HI-6 and 2-PAM Inside Human AChE Sarin and VX Conjugates. ACS OMEGA 2020; 5:4490-4500. [PMID: 32175496 PMCID: PMC7066550 DOI: 10.1021/acsomega.9b03737] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 11/04/2019] [Accepted: 02/12/2020] [Indexed: 06/10/2023]
Abstract
The deleterious effects of nerve agents over the enzymes acetylcholinesterase (AChE) and butyrylcholinesterase (BChE) turned these compounds into the most dangerous chemical weapons known. Among the antidotes in use today against these agents, oximes in combination with other drugs are the only treatment with any action. HI-6 and 2-PAM are cationic oximes proved to be effective for the reactivation of AChE inhibited by the nerve agents VX and sarin (GB). However, when it comes to reactivation of AChE inside the central or peripheral nervous systems, charged molecules present low diffusion due to low penetration through the blood-brain barrier. Uncharged oximes appear as an interesting alternative to solve this problem, but the development and enhancement of more efficient uncharged oximes capable of reactivating human AChE is still necessary. Given the limitations for in vivo and in vitro experimental studies with nerve agents, modeling is an important tool that can contribute to a better understanding of factors that may affect the efficiency of uncharged oximes. In order to investigate the interaction and behavior of cationic and uncharged oximes, we performed here molecular docking, molecular dynamics simulations, and binding energies calculations of the known cationic oximes HI-6 and 2-PAM plus four uncharged oximes found in the literature, complexed with human AChE (HssACHE) conjugated with the nerve agents VX and GB. The uncharged oximes showed different behaviors, especially RS194B, which presented stability inside AChE-VX, but presented free binding energy lower than cationic oximes, suggesting that structural alterations could favor its interactions with these complexes. In contrast, HI-6 and 2-PAM showed higher affinities with more negative binding energy values and larger contribution of the amino acid Asp74, demonstrating the importance of the quaternary nitrogen to the affinity and interaction of oximes with AChE-GB and AChE-VX conjugates.
Collapse
Affiliation(s)
- Felipe
Rodrigues de Souza
- Laboratory
of Molecular Modeling Applied
to Chemical and Biological Defense (LMCBD), Military Institute of Engineering, 22290-270 Rio de Janeiro/RJ, Brazil
- Department
of Chemistry, Pontifical Catholic University
of Rio de Janeiro, 22451-900 Rio de Janeiro/RJ, Brazil
| | - Danielle Rodrigues Garcia
- Laboratory
of Molecular Modeling Applied
to Chemical and Biological Defense (LMCBD), Military Institute of Engineering, 22290-270 Rio de Janeiro/RJ, Brazil
| | - Teobaldo Cuya
- Faculty
of Technology, University of the State of
Rio de Janeiro, 27537-000 Resende/RJ, Brazil
| | - André Silva Pimentel
- Department
of Chemistry, Pontifical Catholic University
of Rio de Janeiro, 22451-900 Rio de Janeiro/RJ, Brazil
| | - Arlan da Silva Gonçalves
- Postgraduate
Program in Sustainable Technologies (PPGTECS), Federal Institute of Education Science and Technology of Espírito
Santo, Unit Vila Velha, 29056-255 Vila Velha/ES, Brazil
- Postgraduate
Program in Chemistry (PPGQUI), Federal University
of Espírito Santo, 29075-910 Vitória, ESBrazil
| | | | - Tanos Celmar Costa França
- Laboratory
of Molecular Modeling Applied
to Chemical and Biological Defense (LMCBD), Military Institute of Engineering, 22290-270 Rio de Janeiro/RJ, Brazil
- Department
of Chemistry, Faculty of Science, University
of Hradec Kralove, Rokitanskeho
62, 50003 Hradec
Kralove, Czech Republic
| |
Collapse
|
5
|
Reymond C, Jaffré N, Taudon N, Menneteau M, Chaussard H, Denis J, Castellarin C, Dhote F, Dorandeu F. Superior efficacy of HI-6 dimethanesulfonate over pralidoxime methylsulfate against Russian VX poisoning in cynomolgus monkeys (Macaca fascicularis). Toxicology 2018; 410:96-105. [PMID: 30218682 DOI: 10.1016/j.tox.2018.09.005] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/13/2018] [Revised: 09/06/2018] [Accepted: 09/09/2018] [Indexed: 11/30/2022]
Abstract
Organophosphorus nerve agents still represent a serious risk to human health. In the French armed forces, the current emergency treatment against OP intoxications is a fully licensed wet-dry dual-chambered autoinjector (Ineurope ®), that contains pralidoxime methylsulfate (2-PAM) to reactivate inhibited acetylcholinesterase (AChE), atropine sulfate (AS) and avizafone chlorhydrate (AVZ). While this treatment is effective against several of the known nerve agents, it shows little efficacy against the Russian VX (VR), one of the most toxic compounds. HI-6 dimethanesulfonate (HI-6 DMS) is an oxime able to reactivate in vitro and in vivo VR-inhibited AChE. To confirm the superiority of HI-6 DMS towards 2-PAM prior to licensing, we compared the two 3-drug-combinations (HI-6 vs 2-PAM, 33 and 18 mg/kg respectively, equimolar doses; AS/AVZ 0.25/0.175 mg/kg respectively) in VR-poisoned cynomolgus macaques, the model required by the French drug regulatory agency. In parallel we performed HI-6 pharmacokinetics analysis using a one compartment model. A better efficacy of the HI-6 DMS combination was clearly observed: up to 5 LD50 of VR (i.m.), a single administration of the HI-6 DMS combination, shortly after the onset of clinical signs, prevented death of the four intoxicated animals. Conversely 2-PAM only prevented death in one out of three subjects exposed to the same amount of VR. As expected with V agents, reinhibition of blood AChE was observed but without any apparent impact on the clinical recovery of the animals. A single administration of the HI-6 DMS combination was still but partially effective at 15 LD50 of VR, allowing a 50% survival rate.
Collapse
Affiliation(s)
- Chloé Reymond
- Institut de Recherche Biomédicale des Armées (IRBA), département de Toxicologie et Risques Chimiques, F-91 220 Brétigny-sur-Orge, France
| | - Nina Jaffré
- Institut de Recherche Biomédicale des Armées (IRBA), département de Toxicologie et Risques Chimiques, F-91 220 Brétigny-sur-Orge, France.
| | - Nicolas Taudon
- Institut de Recherche Biomédicale des Armées (IRBA), département des Plateformes et Recherche Technologique, F-91 220 Brétigny-sur-Orge, France
| | - Mathilde Menneteau
- Institut de Recherche Biomédicale des Armées (IRBA), département de Toxicologie et Risques Chimiques, F-91 220 Brétigny-sur-Orge, France
| | - Hervé Chaussard
- Institut de Recherche Biomédicale des Armées (IRBA), unité Animalerie, F-91 220 Brétigny-sur-Orge, France
| | - Josiane Denis
- Institut de Recherche Biomédicale des Armées (IRBA), département de Toxicologie et Risques Chimiques, F-91 220 Brétigny-sur-Orge, France
| | - Cédric Castellarin
- Institut de Recherche Biomédicale des Armées (IRBA), département des Plateformes et Recherche Technologique, F-91 220 Brétigny-sur-Orge, France
| | - Franck Dhote
- Institut de Recherche Biomédicale des Armées (IRBA), département de Toxicologie et Risques Chimiques, F-91 220 Brétigny-sur-Orge, France
| | - Frédéric Dorandeu
- Institut de Recherche Biomédicale des Armées (IRBA), département de Toxicologie et Risques Chimiques, F-91 220 Brétigny-sur-Orge, France; Ecole du Val-de-Grâce, 1 place Alphonse Laveran, 75230 Paris, France
| |
Collapse
|
6
|
A primer on nerve agents: what the emergency responder, anesthesiologist, and intensivist needs to know. Can J Anaesth 2017; 64:1059-1070. [PMID: 28766156 DOI: 10.1007/s12630-017-0920-2] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/26/2017] [Revised: 06/03/2017] [Accepted: 06/19/2017] [Indexed: 12/19/2022] Open
Abstract
PURPOSE The purpose of this review article is to familiarize first responders, anesthesiologists, and intensivists with the medical management of patients exposed to nerve agents. SOURCE This review is based on the current medical literature available to the general medical community. PRINCIPAL FINDINGS Nerve agents are some of the deadliest substances known to humanity. Though they kill primarily via muscle paralysis, which leads to respiratory arrest, these agents affect virtually every organ system in the body. Their primary mechanism of action is the body-wide inhibition of cholinesterases. This inhibition leads to the accumulation of acetylcholine, stimulating both nicotinic and muscarinic receptors. After decontamination, the primary treatment is with atropine to control muscarinic symptoms and with oximes to reactivate the cholinesterases and treat the nicotinic symptoms. Atropine doses can be much higher than conventionally used. Seizures are generally best treated with benzodiazepines. Patients with substantial exposure may require ventilatory and intensive care unit support for prolonged periods of time. CONCLUSION While it is unlikely that most medical practitioners will ever encounter nerve agent poisoning, it is critical to be aware of the presenting symptoms and how best to treat patients exposed to these deadly agents. History has shown that rapid medical treatment can easily mean the difference between life and death for a patient in this situation.
Collapse
|
7
|
Kassa J, Jun D, Kuca K. The Reactivating and Therapeutic Efficacy of Oximes to Counteract Russian VX Poisonings. Int J Toxicol 2016; 25:397-401. [PMID: 16940011 DOI: 10.1080/10915810600846971] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/24/2022]
Abstract
Russian VX ( O-isobutyl- S-(2-diethylaminoethyl)methylphosphonothioate) is the structural analogue of VX agent. It differs from VX agent ( O-ethyl- S-(2-diisopropylaminoethyl) methylphosphonothioate) by two alkyl groups. The potency of currently available oximes (pralidoxime, obidoxime, HI-6) to reactivate Russian VX–inhibited acetylcholinesterase and to eliminate Russian VX–induced acute toxic effects was evaluated using in vivo methods. In vivo determined percentage of reactivation of Russian VX–inhibited blood and brain acetylcholinesterase in poisoned rats shows that HI-6 seems to be the most efficacious reactivator of Russian VX–inhibited acetylcholinesterase among currently used oximes in the peripheral compartment, whereas no difference between reactivating efficacy of all tested oximes was observed in the central compartment. The oxime HI-6 was also found to be the most efficacious oxime in the elimination of acute lethal toxic effects in Russian VX–poisoned mice among all studied oximes. Thus, the oxime HI-6 seems to be the most suitable oxime for the antidotal treatment of acute poisonings with Russian VX as in the case of VX, sarin, cyclosarin, and soman poisonings.
Collapse
Affiliation(s)
- Jiri Kassa
- Department of Toxicology, Faculty of Military Health Sciences, Hradec Kralove, Czech Republic.
| | | | | |
Collapse
|
8
|
Daczkowski CM, Pegan SD, Harvey SP. Engineering the Organophosphorus Acid Anhydrolase Enzyme for Increased Catalytic Efficiency and Broadened Stereospecificity on Russian VX. Biochemistry 2015; 54:6423-33. [PMID: 26418828 DOI: 10.1021/acs.biochem.5b00624] [Citation(s) in RCA: 28] [Impact Index Per Article: 3.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Abstract
The enzyme organophosphorus acid anhydrolase (OPAA), from Alteromonas sp. JD6.5, has been shown to rapidly catalyze the hydrolysis of a number of toxic organophosphorus compounds, including several G-type chemical nerve agents. The enzyme was cloned into Escherichia coli and can be produced up to approximately 50% of cellular protein. There have been no previous reports of OPAA activity on VR {Russian VX, O-isobutyl S-[2-(diethylamino)ethyl] methylphosphonothioate}, and our studies reported here show that wild-type OPAA has poor catalytic efficacy toward VR. However, via application of a structurally aided protein engineering approach, significant improvements in catalytic efficiency were realized via optimization of the small pocket within the OPAA's substrate-binding site. This optimization involved alterations at only three amino acid sites resulting in a 30-fold increase in catalytic efficiency toward racemic VR, with a strong stereospecificity toward the P(+) enantiomer. X-ray structures of this mutant as well as one of its predecessors provide potential structural rationales for their effect on the OPAA active site. Additionally, a fourth mutation at a site near the small pocket was found to relax the stereospecificity of the OPAA enzyme. Thus, it allows the altered enzyme to effectively process both VR enantiomers and should be a useful genetic background in which to seek further improvements in OPAA VR activity.
Collapse
Affiliation(s)
- Courtney M Daczkowski
- Department of Pharmaceutical and Biomedical Sciences, University of Georgia , Athens, Georgia 30602, United States
| | - Scott D Pegan
- Department of Pharmaceutical and Biomedical Sciences, University of Georgia , Athens, Georgia 30602, United States.,U.S. Army Reserve 377th Sustainment Command Detachment 8 , Aberdeen Proving Ground, Maryland 21010-5424, United States
| | - Steven P Harvey
- U.S. Army Edgewood Chemical Biological Center , Aberdeen Proving Ground, Maryland 21010-5424, United States
| |
Collapse
|
9
|
Cuquel AC, Dorandeu F, Ceppa F, Renard C, Burnat P. [The VR, the Russian version of the nerve agent VX]. ANNALES PHARMACEUTIQUES FRANÇAISES 2015; 73:180-9. [PMID: 25592653 DOI: 10.1016/j.pharma.2014.11.005] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/18/2014] [Revised: 11/20/2014] [Accepted: 11/21/2014] [Indexed: 10/24/2022]
Abstract
A product of the arms race during the Cold War, the Russian VX, or VR, is an organophosphorus compound that is a structural isomer of the western VX compound (or A4), with which it shares a very high toxicity. It is much less studied and known than VX because the knowledge of its existence is relatively recent. A very low volatility and high resistance in the environment make it a persistent agent. Poisoning occurs mainly following penetration through skin and mucosa but vapour inhalation is a credible risk in some circumstances. The clinical presentation may be differed by several hours and despite the absence of signs and symptoms, the casualty should not be considered as contamination or intoxication-free. This agent has a long residence time in blood, a characteristics that clearly differentiates it from other compounds such as sarin. The protocols for antidote administration may thus have to be changed accordingly. The fact that VR poisoned individuals will less respond to the current oxime therapy used in France, the 2-PAM and that VR represents a higher threat than VX, being probably possessed by some proliferating states, justify the interest for this toxic product.
Collapse
Affiliation(s)
- A-C Cuquel
- Fédération de pharmacie-biologie médicale, HIA Val-de-Grâce, 74, boulevard de Port-Royal 75230 Paris cedex, France
| | - F Dorandeu
- Département de toxicologie et risques chimiques, institut de recherche biomédicale des armées, BP 73, 91223 Brétigny-sur-Orge, France
| | - F Ceppa
- Fédération de biologie médicale, hôpital d'instruction des armées Bégin, 94163 Saint-Mandé cedex, France
| | - C Renard
- Fédération de pharmacie-biologie médicale, HIA Val-de-Grâce, 74, boulevard de Port-Royal 75230 Paris cedex, France
| | - P Burnat
- Fédération de biologie médicale, hôpital d'instruction des armées Bégin, 94163 Saint-Mandé cedex, France.
| |
Collapse
|
10
|
da Cunha Xavier Soares SF, Vieira AA, Delfino RT, Figueroa-Villar JD. NMR determination of Electrophorus electricus acetylcholinesterase inhibition and reactivation by neutral oximes. Bioorg Med Chem 2013; 21:5923-30. [DOI: 10.1016/j.bmc.2013.05.063] [Citation(s) in RCA: 18] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/12/2013] [Revised: 05/21/2013] [Accepted: 05/29/2013] [Indexed: 12/20/2022]
|
11
|
Mikler J, Tenn C, Worek F, Reiter G, Thiermann H, Garrett M, Bohnert S, Sawyer T. Immobilization of Russian VX skin depots by localized cooling: Implications for decontamination and medical countermeasures. Toxicol Lett 2011; 206:47-53. [DOI: 10.1016/j.toxlet.2011.05.1047] [Citation(s) in RCA: 11] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/09/2011] [Accepted: 05/30/2011] [Indexed: 10/18/2022]
|
12
|
Lundy PM, Hamilton MG, Sawyer TW, Mikler J. Comparative protective effects of HI-6 and MMB-4 against organophosphorous nerve agent poisoning. Toxicology 2011; 285:90-6. [DOI: 10.1016/j.tox.2011.04.006] [Citation(s) in RCA: 40] [Impact Index Per Article: 3.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/11/2011] [Revised: 04/04/2011] [Accepted: 04/08/2011] [Indexed: 10/18/2022]
|
13
|
Tiwari S, Ghosh KK, Marek J, Kuca K. Functionalized surfactant mediated reactions of carboxylate, phosphate and sulphonate esters. J PHYS ORG CHEM 2010. [DOI: 10.1002/poc.1635] [Citation(s) in RCA: 16] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/05/2022]
|
14
|
Time-Course Changes of Acetylcholinesterase Activity in Blood and Some Tissues in Rats After Intoxication by Russian VX. Neurotox Res 2009; 16:356-60. [DOI: 10.1007/s12640-009-9102-5] [Citation(s) in RCA: 13] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/19/2008] [Revised: 03/05/2009] [Accepted: 08/19/2009] [Indexed: 10/20/2022]
|
15
|
Hajek P, Bajgar J, Slizova D, Krs O, Kuca K, Capek L, Fusek J. Different inhibition of acetylcholinesterase in selected parts of the rat brain following intoxication with VX and Russian VX. Drug Chem Toxicol 2009; 32:1-8. [DOI: 10.1080/01480540802391062] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/20/2022]
|
16
|
Tiwari S, Kolay S, Ghosh KK, Kuca K, Marek J. Kinetic study of the reactions ofp-nitrophenyl acetate andp-nitrophenyl benzoate with oximate nucleophiles. INT J CHEM KINET 2009. [DOI: 10.1002/kin.20363] [Citation(s) in RCA: 18] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/09/2022]
|
17
|
Pejchal J, Osterreicher J, Kuca K, Jun D, Bajgar J, Kassa J. The influence of acetylcholinesterase reactivators on selected hepatic functions in rats. Basic Clin Pharmacol Toxicol 2008; 103:119-23. [PMID: 18816293 DOI: 10.1111/j.1742-7843.2008.00249.x] [Citation(s) in RCA: 17] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/26/2022]
Abstract
The aim of our study was to evaluate the impact of acetylcholinesterase reactivators--K027 [1-(4-carbamoyl pyridinium)-3-(4-hydroxyiminomethyl pyridinium) propane dibromide], HI-6 [1-(4-carbamoylpyridinium)-3-(2-hydroxyimino methylpyridinium) oxapropane dichloride] and obidoxime [1,3-bis(4-hydroxyiminomethyl pyridinium)oxapropane dichloride] on hepatic functions in vivo. Male Wistar rats were randomly divided to seven groups and intramuscularly administered with saline and acetylcholinesterase reactivators (K027, HI-6 and obidoxime) at doses of 5% LD(50) and 50% LD(50). Liver tissue samples were taken 24 hr after administration. Histochemical detection of lipid droplets and immunohistochemical detection of multidrug resistance protein 2 (Mrp2) were provided. Lipid droplet count in rat liver did not show any significant differences in animals administered with K027, HI-6 and obidoxime in comparison with the control group. Mrp2 protein expression significantly decreased when animals were administered with K027 at a dose of 50% LD(50) and HI-6 and obidoxime at doses of 5% LD(50) and 50% LD(50), when compared to the controls. No statistical differences of Mrp2 expression were measured when animals were administered with K027 at a dose of 5% LD(50) in comparison with control animals. We found impaired hepatic transporter function after administration of HI-6, obidoxime and higher concentration of K027, which might be the underlying mechanism of acetylcholinesterase reactivators' hepatotoxicity.
Collapse
Affiliation(s)
- Jaroslav Pejchal
- Center of Advanced Studies, Faculty of Military Health Sciences, University of Defence, Hradec Kralove, Czech Republic
| | | | | | | | | | | |
Collapse
|
18
|
Lorke D, Hasan M, Nurulain S, Shafiullah M, Nagelkerke N, Petroianu G. Effect of intrathecal pralidoxime administration upon survival of rats exposed to the organophosphate paraoxon. Neurotoxicology 2008; 29:663-70. [DOI: 10.1016/j.neuro.2008.03.006] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/10/2007] [Revised: 12/04/2007] [Accepted: 03/14/2008] [Indexed: 11/29/2022]
|
19
|
Lorke DE, Hasan MY, Nurulain SM, Sheen R, Kuca K, Petroianu GA. Entry of two new asymmetric bispyridinium oximes (K-27 and K-48) into the rat brain: comparison with obidoxime. J Appl Toxicol 2007; 27:482-90. [PMID: 17309042 DOI: 10.1002/jat.1229] [Citation(s) in RCA: 47] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/09/2022]
Abstract
In the search for new oximes with higher reactivation potency and a broader spectrum, K-27 and K-48, have recently been synthesized. To test if their superior efficacy was related to better penetration across the blood-brain barrier, their brain entry was compared with that of obidoxime, when administered either alone or after the organophosphate paraoxon (POX). Rats received 50 micromol obidoxime, K-27 or K-48, either alone or in addition to 1 micromol POX. Oxime concentrations at various points in time in brain and plasma were measured using HPLC. The obidoxime C(max) in brain was 1.3% of the plasma C(max) when injected alone, and 1.5% when injected following POX. The ratio of the area under the curve (AUC) brain to plasma for obidoxime was around 6%, irrespective of whether it was administered alone or after POX. For K-27, C(max) (brain) was 0.6% of C(max) (plasma) when injected alone, and 0.7% when injected after POX (no significant difference). The AUC (brain) was 2% of AUC (plasma) for both K-27 groups. K-48, when injected alone reached 1.4% of C(max) (plasma) in the brain and 1.2% of C(max) (plasma), when injected following POX. The AUC (brain) was 5% of the AUC (plasma), both when K-48 was administered alone and in combination with POX. Entry of all three oximes into the brain is minimal and cannot explain the better therapeutic efficacy of K-27 and K-48. As already observed for pralidoxime, injection of POX before oxime administration had no influence upon penetration across the blood-brain barrier.
Collapse
Affiliation(s)
- D E Lorke
- Department of Anatomy, FMHS, UAE University, Al Ain, United Arab Emirates
| | | | | | | | | | | |
Collapse
|
20
|
Musilek K, Jun D, Cabal J, Kassa J, Gunn-Moore F, Kuca K. Design of a Potent Reactivator of Tabun-Inhibited AcetylcholinesteraseSynthesis and Evaluation of (E)-1-(4-Carbamoylpyridinium)-4-(4-hydroxyiminomethylpyridinium)-but-2-ene Dibromide (K203). J Med Chem 2007; 50:5514-8. [DOI: 10.1021/jm070653r] [Citation(s) in RCA: 82] [Impact Index Per Article: 4.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Affiliation(s)
- Kamil Musilek
- Department of Toxicology, and Center of Advanced Studies, Faculty of Military Health Sciences, University of Defense, Department of Pharmaceutical Chemistry and Drug Control, Faculty of Pharmacy, Charles University, Prague, Czech Republic, School of Biology, University of St. Andrews, St. Andrews, Fife, United Kingdom
| | - Daniel Jun
- Department of Toxicology, and Center of Advanced Studies, Faculty of Military Health Sciences, University of Defense, Department of Pharmaceutical Chemistry and Drug Control, Faculty of Pharmacy, Charles University, Prague, Czech Republic, School of Biology, University of St. Andrews, St. Andrews, Fife, United Kingdom
| | - Jiri Cabal
- Department of Toxicology, and Center of Advanced Studies, Faculty of Military Health Sciences, University of Defense, Department of Pharmaceutical Chemistry and Drug Control, Faculty of Pharmacy, Charles University, Prague, Czech Republic, School of Biology, University of St. Andrews, St. Andrews, Fife, United Kingdom
| | - Jiri Kassa
- Department of Toxicology, and Center of Advanced Studies, Faculty of Military Health Sciences, University of Defense, Department of Pharmaceutical Chemistry and Drug Control, Faculty of Pharmacy, Charles University, Prague, Czech Republic, School of Biology, University of St. Andrews, St. Andrews, Fife, United Kingdom
| | - Frank Gunn-Moore
- Department of Toxicology, and Center of Advanced Studies, Faculty of Military Health Sciences, University of Defense, Department of Pharmaceutical Chemistry and Drug Control, Faculty of Pharmacy, Charles University, Prague, Czech Republic, School of Biology, University of St. Andrews, St. Andrews, Fife, United Kingdom
| | - Kamil Kuca
- Department of Toxicology, and Center of Advanced Studies, Faculty of Military Health Sciences, University of Defense, Department of Pharmaceutical Chemistry and Drug Control, Faculty of Pharmacy, Charles University, Prague, Czech Republic, School of Biology, University of St. Andrews, St. Andrews, Fife, United Kingdom
| |
Collapse
|
21
|
Kuca K, Jun D, Cabal J, Musilova L. Bisquaternary Oximes as Reactivators of Tabun-Inhibited Human Brain Cholinesterases: An in vitro Study. Basic Clin Pharmacol Toxicol 2007; 101:25-8. [PMID: 17577312 DOI: 10.1111/j.1742-7843.2007.00085.x] [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: 11/30/2022]
Abstract
Intoxications caused by tabun nerve agent are generally very hard to treat by convential acetylcholinesterase (AChE) reactivators. Due to this, new AChE reactivators are still developed. In this study, we have tested three new promising bisquaternary AChE reactivators: K027, K033 and K048. These reactivators were previously tested on rat brain homogenate. To mimic reality, we studied the potency of these new oximes to reactivate tabun-inhibited human brain cholinesterases. As is evident from the results, reactivator K048 (reactivation 40%) surpassed all reactivators tested in this study [including the most promising ones, namely trimedoxime (37%) and obidoxime (33%)]. Moreover, if compared to our previous results from rat brain studies, species differences were demonstrated.
Collapse
Affiliation(s)
- Kamil Kuca
- Center of Advanced Studies, Faculty of Military Health Sciences, University of Defence, Hradec Kralove, Czech Republic.
| | | | | | | |
Collapse
|
22
|
Arduini F, Amine A, Moscone D, Ricci F, Palleschi G. Fast, sensitive and cost-effective detection of nerve agents in the gas phase using a portable instrument and an electrochemical biosensor. Anal Bioanal Chem 2007; 388:1049-57. [PMID: 17508205 DOI: 10.1007/s00216-007-1330-z] [Citation(s) in RCA: 59] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/31/2007] [Revised: 04/24/2007] [Accepted: 04/26/2007] [Indexed: 10/23/2022]
Abstract
The nerve agents are chemical warfare agents known to be used during terrorist attacks. An inexpensive and portable system to be used by first responders and military personnel is of interest owing to the continuing threat of possible terrorist attacks. Amperometric biosensors based on cholinesterase inhibition show such potentialities. In this work butyrylcholinesterase was immobilized onto screen-printed electrodes modified with Prussian blue and the nerve agent detection was performed by measuring the residual activity of enzyme. The optimized biosensor was tested with sarin and VX standard solutions, showing detection limits of 12 and 14 ppb (10% of inhibition), respectively. The enzymatic inhibition was also obtained by exposing the biosensors to sarin in gas phase. Two different concentrations of sarin gas (0.1 and 0.5 mg m(-3)) at different incubation times (from 30 s up to 10 min) were tested. It is possible to detect sarin at a concentration of 0.1 mg m(-3) with 30-s incubation time, with a degree of inhibition of 34%, which match the legal limits (immediate danger to life and health).
Collapse
Affiliation(s)
- Fabiana Arduini
- Dipartimento di Scienze e Tecnologie Chimiche, Università di Roma Tor Vergata, Via della Ricerca Scientifica, Rome, Italy.
| | | | | | | | | |
Collapse
|
23
|
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.
Collapse
Affiliation(s)
- Biljana Antonijevic
- Institute of Toxicological Chemistry, Faculty of Pharmacy, University of Belgrade, Vojvode Stepe 450, 11221 Belgrade, Serbia.
| | | |
Collapse
|
24
|
Bajgar J, Kuca K, Fusek J, Karasova J, Kassa J, Cabal J, Jun D, Blaha V. Inhibition of blood cholinesterases following intoxication with VX and its derivatives. J Appl Toxicol 2007; 27:458-63. [PMID: 17299830 DOI: 10.1002/jat.1226] [Citation(s) in RCA: 11] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/07/2022]
Abstract
Nerve agents can be divided into G-agents (sarin, soman, tabun, cyclosarin etc.) and V-agents. The studies dealing with V-agents (O-alkyl S-2-dialkylaminoethyl methyl phosphonothiolates) are limited to one or two representatives only (VX, Russian VX). Anticholinesterase properties of 11 V-agents were studied in rats in vivo. Following intoxication with these agents in doses of 1 x LD(50) (intramuscular administration), activities of cholinesterases in the blood were continuously monitored and half-lives (t(0.5)) of inhibition were determined. These values varied from 3 min (VX and some other agents) to 10-14 min (derivatives substituted on the phosphorus head by O-ethyl- or O-isopropyl-, and by dimethyl-, diethyl- and dibutyl- on the nitrogen). Acetylcholinesterase activities in selected parts of the brain and diaphragm (30 min after the intoxication) were also detected. A correlation between toxicities and rates of inhibition of the blood enzymes was demonstrated. A similar relationship between acetylcholinesterase inhibition in vitro (from literature data) and half-lives of the blood cholinesterases was also observed. Though the chemical similarity of V compounds is evident, marked differences were observed among different derivatives; however, all agents examined had high inhibition potency corresponding to their toxicities.
Collapse
Affiliation(s)
- J Bajgar
- Department of Toxicology, Faculty of Military Health Sciences, University of Defence, Trebesska 1575, 500 01 Hradec Kralove, Czech Republic.
| | | | | | | | | | | | | | | |
Collapse
|
25
|
Lundy PM, Raveh L, Amitai G. Development of the Bisquaternary Oxime HI-6 Toward Clinical Use in the Treatment of Organophosphate Nerve Agent Poisoning. ACTA ACUST UNITED AC 2006; 25:231-43. [PMID: 17288495 DOI: 10.2165/00139709-200625040-00004] [Citation(s) in RCA: 70] [Impact Index Per Article: 3.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/02/2022]
Abstract
The traditional therapeutic treatment of organophosphate cholinesterase inhibitor (nerve agents) poisoning consists of co-treatment with an antimuscarinic (atropine) and a reactivator of inhibited acetylcholinesterase (AChE), which contains a nucleophilic oxime function. Two oximes are presently widely available for clinical use, pralidoxime and obidoxime (toxogonin), but both offer little protection against important nerve agent threats. This has highlighted the real need for the development and availability of more effective oximes for human use, a search that has been going on for up to 30 years. However, despite the demonstration of more effective and safe oximes in animal experiments, no additional oximes have been licensed for human use. HI-6, (1-[[[4(aminocarbonyl)-pyridinio]methoxy]methyl]-2(hydroxyimino)pyridinium dichloride; CAS 34433-31-3) has been studied intensively and has been proved effective in a variety of species including non-human primates and appears from clinical experience to be safe in humans. These studies have led to the fielding of HI-6 for use against nerve agents by the militaries of the Czech republic, Sweden, Canada and under certain circumstances the Organisation for the Prohibition of Chemical Weapons. Nevertheless HI-6 has not been granted a license for clinical use, must be used only under restricted guidelines and is not available for civilian use as far as is known. This article will highlight those factors relating to HI-6 that pertain to the licensing of new compounds of this type, including the mechanism of action, the clinical and pre-clinical demonstration of safety and its efficacy against a variety of nerve agents particularly in non-human primates, since no relevant human population exists. This article also contains important data on the use of HI-6 in baboons, which has not been available previously. The article also discusses the possibility of successful therapy with HI-6 against poisoning in humans relative to doses used in non-human primates and relative to its ability to reactivate inhibited human AChE.
Collapse
Affiliation(s)
- Paul M Lundy
- Therapeutic Response, Medicine Hat, Alberta, Canada
| | | | | |
Collapse
|