Reversal of succinylcholine induced apnea with an organophosphate scavenging recombinant butyrylcholinesterase.

PubMed

Geyer, Brian C; Larrimore, Katherine E; Kilbourne, Jacquelyn; Kannan, Latha; Mor, Tsafrir S

2013-01-01

Concerns about the safety of paralytics such as succinylcholine to facilitate endotracheal intubation limit their use in prehospital and emergency department settings. The ability to rapidly reverse paralysis and restore respiratory drive would increase the safety margin of an agent, thus permitting the pursuit of alternative intubation strategies. In particular, patients who carry genetic or acquired deficiency of butyrylcholinesterase, the serum enzyme responsible for succinylcholine hydrolysis, are susceptible to succinylcholine-induced apnea, which manifests as paralysis, lasting hours beyond the normally brief half-life of succinylcholine. We hypothesized that intravenous administration of plant-derived recombinant BChE, which also prevents mortality in nerve agent poisoning, would rapidly reverse the effects of succinylcholine. Recombinant butyrylcholinesterase was produced in transgenic plants and purified. Further analysis involved murine and guinea pig models of succinylcholine toxicity. Animals were treated with lethal and sublethal doses of succinylcholine followed by administration of butyrylcholinesterase or vehicle. In both animal models vital signs and overall survival at specified intervals post succinylcholine administration were assessed. Purified plant-derived recombinant human butyrylcholinesterase can hydrolyze succinylcholine in vitro. Challenge of mice with an LD100 of succinylcholine followed by BChE administration resulted in complete prevention of respiratory inhibition and concomitant mortality. Furthermore, experiments in symptomatic guinea pigs demonstrated extremely rapid succinylcholine detoxification with complete amelioration of symptoms and no apparent complications. Recombinant plant-derived butyrylcholinesterase was capable of counteracting and reversing apnea in two complementary models of lethal succinylcholine toxicity, completely preventing mortality. This study of a protein antidote validates the feasibility of protection and treatment of overdose from succinylcholine as well as other biologically active butyrylcholinesterase substrates.

A Cocaine Hydrolase Engineered from Human Butyrylcholinesterase Selectively Blocks Cocaine Toxicity and Reinstatement of Drug Seeking in Rats

PubMed Central

Brimijoin, Stephen; Gao, Yang; Anker, Justin J; Gliddon, Luke A; LaFleur, David; Shah, R; Zhao, Qinghai; Singh, M; Carroll, Marilyn E

2008-01-01

Successive rational mutations of human butyrylcholinesterase (BChE) followed by fusion to human serum albumin have yielded an efficient hydrolase that offers realistic options for therapy of cocaine overdose and abuse. This albumin-BChE prevented seizures in rats given a normally lethal cocaine injection (100 mg/kg, i.p.), lowered brain cocaine levels even when administered after the drug, and provided rescue after convulsions commenced. Moreover, it selectively blocked cocaine-induced reinstatement of drug seeking in rats that had previously self-administered cocaine. The enzyme treatment was well tolerated and may be worth exploring for clinical application in humans. PMID:18199998

Accelerating cocaine metabolism as an approach to the treatment of cocaine abuse and toxicity

PubMed Central

Schindler, Charles W; Goldberg, Steven R

2012-01-01

One pharmacokinetic approach to the treatment of cocaine abuse and toxicity involves the development of compounds that can be safely administered to humans and that accelerate the metabolism of cocaine to inactive components. Catalytic antibodies have been developed and shown to accelerate cocaine metabolism, but their catalytic efficiency for cocaine is relatively low. Mutations of human butyrylcholinesterase and a bacterial cocaine esterase found in the soil of coca plants have also been developed. These compounds accelerate cocaine metabolism and antagonize the behavioral and toxic effects of cocaine in animal models. Of these two approaches, the human butyrylcholinesterase mutants show the most immediate promise as they would not be expected to evoke an immune response in humans. PMID:22300096

Diisopropylfluorophosphate-sensitive aryl acylamidase activity of fatty acid free human serum albumin.

PubMed

Manoharan, Indumathi; Boopathy, Rathnam

2006-08-15

Butyrylcholinesterase in human plasma and acetylcholinesterase in human red blood cells have aryl acylamidase activity toward o-nitroacetanilide, hydrolyzing the amide bond to produce o-nitroaniline and acetate. People with a genetic variant of butyrylcholinesterase that had no detectable activity with butyrylthiocholine, nevertheless had aryl acylamidase activity in their plasma. To determine the source of this aryl acylamidase activity we tested fatty acid free human albumin for activity. We found that albumin had aryl acylacylamidase activity and that this activity was inhibited by diisopropylfluorophosphate. Since the esterase activity of albumin is also inhibited by diisopropylfluorophosphate, and since it is known that diisopropylfluorophosphate covalently binds to Tyr 411 of human albumin, we conclude that the active site for aryl acylamidase activity of albumin is Tyr 411. Albumin accounts for about 10% of the aryl acylamidase activity in human plasma.

Development of diagnostics in the search of an explanation for toxic airline syndrome 1

PubMed Central

Schopfer, Lawrence M.; Furlong, Clement E.; Lockridge, Oksana

2010-01-01

Toxic airline syndrome is assumed to be caused by exposure to tri-cresyl phosphate, an additive in engine lubricants and hydraulic fluids, which is activated to the toxic 2-(o-cresyl)-4H-1,3,2-benzodioxaphosphoran-2-one (CBDP). At present there is no laboratory evidence to support intoxication of airline crew by CBDP. Our goal was to develop methods for testing in vivo exposure by identifying and characterizing biomarkers. Mass spectrometry was used to study the reaction of CBDP with human albumin, free tyrosine, and human butyrylcholinesterase. Human albumin made a covalent bond with CBDP, adding a mass of 170 to tyrosine 411 to yield the ortho-cresyl phosphotyrosine derivative. Human butyrylcholinesterase made a covalent bond with CBDP on serine 198 to yield 5 adducts with added masses of 80, 108, 156, 170, and 186. The most abundant adduct had an added mass of 80 from phosphate (HPO3), a surprising result since no pesticide or nerve agent is known to yield phosphorylated serine with an added mass of 80. The next most abundant adduct had an added mass of 170 to form ortho-cresyl phosphoserine. It is concluded that toxic gases or oil mists in cabin air may form adducts on plasma butyrylcholinesterase and albumin, detectable by mass spectrometry. PMID:20447373

Quantification of nerve agent VX-butyrylcholinesterase adduct biomarker from an accidental exposure.

PubMed

Solano, Maria I; Thomas, Jerry D; Taylor, James T; McGuire, Jeffrey M; Jakubowski, Edward M; Thomson, Sandra A; Maggio, Vincent L; Holland, Kerry E; Smith, J Richard; Capacio, Benedict; Woolfitt, Adrian R; Ashley, David L; Barr, John R

2008-01-01

The lack of data in the open literature on human exposure to the nerve agent O-ethyl-S-(2-diisopropylaminoethyl) methylphosphonothioate (VX) gives a special relevance to the data presented in this study in which we report the quantification of VX-butyrylcholinesterase adduct from a relatively low-level accidental human exposure. The samples were analyzed by gas chromatography-high resolution mass spectrometry using the fluoride ion regeneration method for the quantification of multiple nerve agents including VX. Six human plasma samples from the same individual were collected after the patient had been treated once with oxime immediately after exhibiting signs of exposure. Detection limits of approximately 5.5 pg/mL plasma were achieved for the G-analogue of VX (G-VX). Levels of the G-VX ranged from 81.4 pg/mL on the first day after the exposure to 6.9 pg/mL in the sample taken 27 days after the exposure. Based on the reported concentration of human butyrylcholinesterase in plasma of approximately 80 nM, it can be calculated that inhibition levels of >or= 0.05% of BuChE can be accurately quantified. These data further indicate that the fluoride ion regeneration method is a potentially powerful tool that can be used to assess low-level exposure to VX.

A new detection method for the K variant of butyrylcholinesterase based on PCR primer introduced restriction analysis (PCR-PIRA).

PubMed Central

Shibuta, K; Abe, M; Suzuki, T

1994-01-01

The K variant of human butyrylcholinesterase is caused by a G/A transition in the butyrylcholinesterase gene, which neither creates nor destroys any restriction site. In an attempt to detect the K variant both simply and rapidly, we developed a two step method of "PCR primer introduced restriction analysis" (PCR-PIRA). The first step was used to introduce a new Fun4HI site into the normal allele for a screening test, while the second step was performed to create a new MaeIII site on the variant allele for a specific test. This method thus enabled us to distinguish clearly the K variant from the normal allele, and also showed that the frequency of the K variant allele is 0.164 in the Japanese population. Images PMID:7966197

Development of diagnostics in the search for an explanation of aerotoxic syndrome.

PubMed

Schopfer, Lawrence M; Furlong, Clement E; Lockridge, Oksana

2010-09-01

Aerotoxic syndrome is assumed to be caused by exposure to tricresyl phosphate, an additive in engine lubricants and hydraulic fluids that is activated to the toxic 2-(ortho-cresyl)-4H-1,3,2-benzodioxaphosphoran-2-one (CBDP). Currently, there is no laboratory evidence to support intoxication of airline crew members by CBDP. Our goal was to develop methods for testing in vivo exposure by identifying and characterizing biomarkers. Mass spectrometry was used to study the reaction of CBDP with human albumin, free tyrosine, and human butyrylcholinesterase. Human albumin made a covalent bond with CBDP, adding a mass of 170amu to Tyr411 to yield the o-cresyl phosphotyrosine derivative. Human butyrylcholinesterase made a covalent bond with CBDP on Ser198 to yield five adducts with added masses of 80, 108, 156, 170, and 186amu. The most abundant adduct had an added mass of 80amu from phosphate (HPO(3)), a surprising result given that no pesticide or nerve agent is known to yield phosphorylated serine with an added mass of 80amu. The next most abundant adduct had an added mass of 170amu to form o-cresyl phosphoserine. It is concluded that toxic gases or oil mists in cabin air may form adducts on plasma butyrylcholinesterase and albumin, detectable by mass spectrometry. 2010 Elsevier Inc. All rights reserved.

Human Serum Butyrylcholinesterase: A Bioscavenger for the Protection of Humans from Organophosphorus Exposure

DTIC Science & Technology

2009-10-01

Current medical countermeasures against OP nerve agent poisoning include a combination of pretreatment with a carbamate, pyridostigmine bromide , to...The protection of primates against soman poisoning by pretreatment with pyridostigmine , J. Pharm. Pharmacol. 31 (1979) 295-299. [2] C.G. McLeod

Cocrystallization studies of full-length recombinant butyrylcholinesterase (BChE) with cocaine

DOE Office of Scientific and Technical Information (OSTI.GOV)

Asojo, Oluwatoyin Ajibola; Asojo, Oluyomi Adebola; Ngamelue, Michelle N.

Human butyrylcholinesterase (BChE; EC 3.1.1.8) is a 340 kDa tetrameric glycoprotein that is present in human serum at about 5 mg l{sup -1} and has well documented therapeutic effects on cocaine toxicity. BChE holds promise as a therapeutic that reduces and finally eliminates the rewarding effects of cocaine, thus weaning an addict from the drug. There have been extensive computational studies of cocaine hydrolysis by BChE. Since there are no reported structures of BChE with cocaine or any of the hydrolysis products, full-length monomeric recombinant wild-type BChE was cocrystallized with cocaine. The refined 3 {angstrom} resolution structure appears to retainmore » the hydrolysis product benzoic acid in sufficient proximity to form a hydrogen bond to the active-site Ser198.« less

The level of aryl acylamidase activity displayed by human butyrylcholinesterase depends on its molecular distribution.

PubMed

Montenegro, M F; Moral-Naranjo, M T; Páez de la Cadena, M; Campoy, F J; Muñoz-Delgado, E; Vidal, C J

2008-09-25

Butyrylcholinesterase (BuChE) and acetylcholinesterase (AChE) display both esterase and aryl acylamidase (AAA) activities. Their AAA activity can be measured using o-nitroacetanilide (ONA). In human samples depleted of acetylcholinesterase, we noticed that the ratio of amidase to esterase activities varied depending on the source, despite both activities being due to BuChE. Searching for an explanation, we compared the activities of BuChE molecular forms in samples of human colon, kidney and serum, and observed that BuChE monomers (G(1)) hydrolyzed o-nitroacetanilide much faster than tetramers (G(4)). This fact suggested that association might cause differences in the AAA site between single and polymerized subunits. This and other post-translational modifications in BuChE subunits probably determine their level of AAA activity. The higher amidase activity of monomers could justify the presence of single BuChE subunits in cells as a way to preserve the AAA activity of BuChE, which could be lost by oligomerization.

Calcium-activated butyrylcholinesterase in human skin protects acetylcholinesterase against suicide inhibition by neurotoxic organophosphates

DOE Office of Scientific and Technical Information (OSTI.GOV)

Schallreuter, Karin U.; Institute for Pigmentary Disorders in Association with EM Arndt University of Greifswald; University of Bradford

The human epidermis holds an autocrine acetylcholine production and degradation including functioning membrane integrated and cytosolic butyrylcholinesterase (BuchE). Here we show that BuchE activities increase 9-fold in the presence of calcium (0.5 x 10{sup -3}M) via a specific EF-hand calcium binding site, whereas acetylcholinesterase (AchE) is not affected. {sup 45}Calcium labelling and computer simulation confirmed the presence of one EF-hand binding site per subunit which is disrupted by H{sub 2}O{sub 2}-mediated oxidation. Moreover, we confirmed the faster hydrolysis by calcium-activated BuchE using the neurotoxic organophosphate O-ethyl-O-(4-nitrophenyl)-phenylphosphonothioate (EPN). Considering the large size of the human skin with 1.8 m{sup 2} surfacemore » area with its calcium gradient in the 10{sup -3}M range, our results implicate calcium-activated BuchE as a major protective mechanism against suicide inhibition of AchE by organophosphates in this non-neuronal tissue.« less

The kinetic study of the inhibition of human cholinesterases by demeton-S-methyl shows that cholinesterase-based titration methods are not suitable for this organophosphate.

PubMed

Bazire, Alexandre; Gillon, Emilie; Lockridge, Oksana; Vallet, Virginie; Nachon, Florian

2011-04-01

The organophosphorus insecticide, demeton-S-methyl (DSM), is considered as a good surrogate of the highly toxic nerve agent VX for skin absorption studies due to similar physico-chemical properties and in vitro percutaneous penetration profile. But, when skin distribution was estimated by measuring inhibition of cholinesterase activity, the results were poorly reproducible. The various grades of commercial DSM solutions were suspected to be the origin of the discrepancies. This hypothesis was tested by measuring inhibition of human acetyl- and butyrylcholinesterase by two commercial DSM solutions. The inhibition rate was independent on the enzyme concentration confirming pseudo-first order conditions. But complete inhibition of butyrylcholinesterase activity was achieved only when the DSM concentration was at least 1500-fold higher than the enzyme concentration. Besides, complete inhibition of acetylcholinesterase was never achieved. Mass spectrometry analysis of the inhibited butyrylcholinesterase adducts identified monomethoxyphosphorylated-serine, the aged product of inhibition by DSM or a derivative with a modified leaving group. Neither spontaneous reactivation nor aging of the dimethoxyphosphorylated-serine could account for the inhibition kinetics observed, suggesting an overly complicated kinetic scheme not compatible with the requirement of a titration experiment. In conclusion, cholinesterase-based analytical methods should be avoided for DSM titration in skin penetration studies. Copyright © 2011 Elsevier Ltd. All rights reserved.

Expression of Biologically Active Human Butyrylcholinesterase in the Cabbage Looper (Trichoplusia ni)

DTIC Science & Technology

2000-01-01

recombinant human BUChE; Sf, Spodoptera frugiperda ; VX, 0-ethyl S-[2-[bis(I -methylethyl)amino]ethyl]methyl phosphonothiolate; wt, wild-type. 1 To whom...ATCC (Rockville, MD, U.S.A.). Insect cells ( Spodoptera frugiperda Sf9 cells and T. ni High 5 cells) and wild-type (wt)-AcNPV were purchased from

Synthesis and biological evaluation of phloroglucinol derivatives possessing α-glycosidase, acetylcholinesterase, butyrylcholinesterase, carbonic anhydrase inhibitory activity.

PubMed

Burmaoglu, Serdar; Yilmaz, Ali O; Taslimi, Parham; Algul, Oztekin; Kilic, Deryanur; Gulcin, Ilhami

2018-02-01

A series of novel phloroglucinol derivatives were designed, synthesized, characterized spectroscopically and tested for their inhibitory activity against selected metabolic enzymes, including α-glycosidase, acetylcholinesterase (AChE), butyrylcholinesterase (BChE), and human carbonic anhydrase I and II (hCA I and II). These compounds displayed nanomolar inhibition levels and showed K i values of 1.14-3.92 nM against AChE, 0.24-1.64 nM against BChE, 6.73-51.10 nM against α-glycosidase, 1.80-5.10 nM against hCA I, and 1.14-5.45 nM against hCA II. © 2018 Deutsche Pharmazeutische Gesellschaft.

Resistance of human butyrylcholinesterase to methylene blue-catalyzed photoinactivation; mass spectrometry analysis of oxidation products.

PubMed

Tacal, Ozden; Li, Bin; Lockridge, Oksana; Schopfer, Lawrence M

2013-01-01

Methylene blue, 3, 7-bis(dimethylamino)-phenothiazin-5-ium chloride, is a reversible inhibitor of human butyrylcholinesterase (BChE) in the absence of light. In the presence of light and oxygen, methylene blue promotes irreversible inhibition of human BChE as a function of time, requiring 3 h irradiation to inhibit 95% activity. Inactivation was accompanied by a progressive loss of Coomassie-stained protein bands on native and denaturing polyacrylamide gels, suggesting backbone fragmentation. Aggregation was not detected. MALDI-TOF/TOF mass spectrometry identified oxidized tryptophan (W52, 56, 231, 376, 412, 490, 522), oxidized methionine (M81, 144, 302, 532, 554, 555), oxidized histidine (H214), oxidized proline (P230), oxidized cysteine (C519) and oxidized serine (S215). A 20 min irradiation in the presence of methylene blue resulted in 17% loss of BChE activity, suggesting that BChE is relatively resistant to methylene blue-catalyzed photoinactivation and that therefore this process could be used to sterilize BChE preparations. © 2012 Wiley Periodicals, Inc. Photochemistry and Photobiology © 2012 The American Society of Photobiology.

Protein tyrosine adduct in humans self-poisoned by chlorpyrifos

PubMed Central

Li, Bin; Eyer, Peter; Eddleston, Michael; Jiang, Wei; Schopfer, Lawrence M.; Lockridge, Oksana

2013-01-01

Studies of human cases of self-inflicted poisoning suggest that chlorpyrifos oxon reacts not only with acetylcholinesterase and butyrylcholinesterase but also with other blood proteins. A favored candidate is albumin because in vitro and animal studies have identified tyrosine 411 of albumin as a site covalently modified by organophosphorus poisons. Our goal was to test this proposal in humans by determining whether plasma from humans poisoned by chlorpyrifos has adducts on tyrosine. Plasma samples from 5 self-poisoned humans were drawn at various time intervals after ingestion of chlorpyrifos for a total of 34 samples. All 34 samples were analyzed for plasma levels of chlorpyrifos and chlorpyrifos oxon (CPO) as a function of time post-ingestion. Eleven samples were analyzed for the presence of diethoxyphosphorylated tyrosine by mass spectrometry. Six samples yielded diethoxyphosphorylated tyrosine in pronase digests. Blood collected as late as 5 days after chlorpyrifos ingestion was positive for CPO-tyrosine, consistent with the 20-day half-life of albumin. High plasma CPO levels did not predict detectable levels of CPO-tyrosine. CPO-tyrosine was identified in pralidoxime treated patients as well as in patients not treated with pralidoxime, indicating that pralidoxime does not reverse CPO binding to tyrosine in humans. Plasma butyrylcholinesterase was a more sensitive biomarker of exposure than adducts on tyrosine. In conclusion, chlorpyrifos oxon makes a stable covalent adduct on the tyrosine residue of blood proteins in humans who ingested chlorpyrifos. PMID:23566956

Insights into (S)-rivastigmine inhibition of butyrylcholinesterase (BuChE): Molecular docking and saturation transfer difference NMR (STD-NMR).

PubMed

Bacalhau, Patrícia; San Juan, Amor A; Goth, Albertino; Caldeira, A Teresa; Martins, Rosário; Burke, Anthony J

2016-08-01

Rivastigmine is a very important drug prescribed for the treatment of Alzheimer's disease (AD) symptoms. It is a dual inhibitor, in that it inhibits both acetylcholinesterase (AChE) and butyrylcholinesterase (BuChE). For our screening program on the discovery of new rivastigmine analogue hits for human butyrylcholinesterase (hBuChE) inhibition, we investigated the interaction of this inhibitor with BuChE using the complimentary approach of the biophysical method, saturation transfer difference (STD)-NMR and molecular docking. This allowed us to obtain essential information on the key binding interactions between the inhibitor and the enzyme to be used for screening of hit compounds. The main conclusions obtained from this integrated study was that the most dominant interactions were (a) H-bonding between the carbamate carbonyl of the inhibitor and the NH group of the imidazole unit of H434, (b) stacking of the aromatic unit of the inhibitor and the W82 aromatic unit in the choline binding pocket via π-π interactions and (c) possible CH/π interactions between the benzylic methyl group and the N-methyl groups of the inhibitor and W82 of the enzyme. Copyright © 2016 Elsevier Inc. All rights reserved.

Joint Service Chemical and Biological Defense Program FY 08-09 Overview

DTIC Science & Technology

2007-10-01

of human plasma-derived butyrylcholinesterase Electronmicrograph of bacillus spores adhering to cell membrane processes Jo i n t Se rv i c e ch e m i...human performance within CB-protective systems. Carbon monolith for electro-swing adsorption Bacillus globigii spores collecting on an...integrated with the ship’s heating, ventilation, and air-conditioning ( HVAC ) systems and provides a filter air supply air for overpressurization of

Inhibitory effects of isatin Mannich bases on carbonic anhydrases, acetylcholinesterase, and butyrylcholinesterase.

PubMed

Ozgun, Dilan Ozmen; Yamali, Cem; Gul, Halise Inci; Taslimi, Parham; Gulcin, Ilhami; Yanik, Telat; Supuran, Claudiu T

2016-12-01

The effects of isatin Mannich bases incorporating (1-[piperidin-1-yl (P1)/morpholin-4-yl (P2)/N-methylpiperazin-1-yl (P3)]methyl)-1H-indole-2,3-dione) moieties against human (h) carbonic anhydrase (CA, EC 4.2.1.1) isoenzymes hCA I and hCA II, acetylcholinesterase (AChE), and butyrylcholinesterase (BChE) enzymes were evaluated. P1-P3 demonstrated impressive inhibition profiles against AChE and BChE and also inhibited both CAs at nanomolar level. These inhibitory effects were more powerful in all cases than the reference compounds used for all these enzymes. This study suggests that isatin Mannich bases P1-P3 are good candidate compounds especially for the development of new cholinesterase inhibitors since they were 2.2-5.9 times better inhibitors than clinically used drug Tacrine.

Cresyl saligenin phosphate makes multiple adducts on free histidine, but does not form an adduct on histidine 438 of human butyrylcholinesterase.

PubMed

Liyasova, Mariya S; Schopfer, Lawrence M; Lockridge, Oksana

2013-03-25

Cresyl saligenin phosphate (CBDP) is a suspected causative agent of "aerotoxic syndrome", affecting pilots, crew members and passengers. CBDP is produced in vivo from ortho-containing isomers of tricresyl phosphate (TCP), a component of jet engine lubricants and hydraulic fluids. CBDP irreversibly inhibits butyrylcholinesterase (BChE) in human plasma by forming adducts on the active site serine (Ser-198). Inhibited BChE undergoes aging to release saligenin and o-cresol. The active site histidine (His-438) was hypothesized to abstract o-hydroxybenzyl moiety from the initial adduct on Ser-198. Our goal was to test this hypothesis. Mass spectral analysis of CBDP-inhibited BChE digested with Glu-C showed an o-hydroxybenzyl adduct (+106 amu) on lysine 499, a residue far from the active site, but not on His-438. Nevertheless, the nitrogen of the imidazole ring of free L-histidine formed a variety of adducts upon reaction with CBDP, including the o-hydroxybenzyl adduct, suggesting that histidine-CBDP adducts may form on other proteins. Copyright © 2012 Elsevier Ireland Ltd. All rights reserved.

Cresyl saligenin phosphate makes multiple adducts on free histidine, but does not form an adduct on histidine 438 of human butyrylcholinesterase

PubMed Central

Liyasova, Mariya S.; Schopfer, Lawrence M.; Lockridge, Oksana

2012-01-01

Cresyl saligenin phosphate (CBDP) is a suspected causative agent of “aerotoxic syndrome”, affecting pilots, crew members and passengers. CBDP is produced in vivo from ortho-containing isomers of tricresyl phosphate (TCP), a component of jet engine lubricants and hydraulic fluids. CBDP irreversibly inhibits butyrylcholinesterase (BChE) in human plasma by forming adducts on the active site serine (Ser-198). Inhibited BChE undergoes aging to release saligenin and o-cresol. The active site histidine (His-438) was hypothesized to abstract o-hydroxybenzyl moiety from the initial adduct on Ser-198. Our goal was to test this hypothesis. Mass spectral analysis of CBDP-inhibited BChE digested with Glu-C showed an o-hydroxybenzyl adduct (+106 amu) on lysine 499, a residue far from the active site, but not on His-438. Nevertheless, the nitrogen of the imidazole ring of free L-histidine formed a variety of adducts upon reaction with CBDP, including the o-hydroxybenzyl adduct, suggesting that histidine-CBDP adducts may form on other proteins. PMID:22898212

A comprehensive evaluation of novel oximes in creation of butyrylcholinesterase-based nerve agent bioscavengers

DOE Office of Scientific and Technical Information (OSTI.GOV)

Katalinić, Maja; Maček Hrvat, Nikolina

A well-considered treatment of acute nerve agents poisoning involves the exogenous administration of butyrylcholinesterase (BChE, EC 3.1.1.8) as a stoichiometric bioscavenger efficient in preventing cholinergic crises caused by acetylcholinesterase (AChE, EC 3.1.1.7) inhibition. An additional improvement in medical countermeasures would be to use oximes that could reactivate BChE as well to upgrade bioscavenging from stoichiometric to oxime-assisted catalytic. Therefore, in this paper we investigated the potency of 39 imidazolium and benzimidazolium oximes (36 compounds synthesized for the first time) to be considered as the reactivators specifically designed for reactivation of phosphylated human BChE. Their efficiency in the reactivation of paraoxon-,more » VX-, and tabun-inhibited human BChE, as well as human AChE was tested and compared with the efficiencies of HI-6 and obidoxime, used in medical practice today. A comprehensive analysis was performed for the most promising oximes defining kinetic parameters of reactivation as well as interactions with uninhibited BChE. Furthermore, experimental data were compared with computational studies (docking, QSAR analysis) as a starting point in future oxime structure refinement. Considering the strict criteria set for in vivo applications, we determined the cytotoxicity of lead oximes on two cell lines. Among the tested oxime library, one imidazolium compound was selected for preliminary in vivo antidotal study in mice. The obtained protection in VX poisoning outlines its potential in development oxime-assisted OP-bioscavenging with BChE. - Highlights: • 36 new imidazolium and benzimidazolium oximes were designed and synthesized. • In vitro reactivation kinetics of phosphylated butyrylcholinesterase was studded. • The modes of actions were elucidated by QSAR and docking simulations. • Protection in VX poisoning was 6.3 × LD{sub 50} in in vivo antidotal study in mice. • Imidazolium oxime-assisted catalysis is feasible for OP-bioscavenging with BChE.« less

Heat pretreatment eliminates spurious butyrylcholinesterase enhancement of endotoxin levels in the kinetic chromogenic assay.

PubMed

Brawner, Andrew; Hinrichs, Steven H; Larson, Marilynn A; Lockridge, Oksana

2016-04-05

The kinetic chromogenic endotoxin assay measures the release of p-nitroaniline from the chromogenic peptide substrate Ac-IEAR-pNA. As part of our project to purify large quantities of human butyrylcholinesterase (HuBChE), we evaluated pure HuBChE for endotoxin levels. We found that HuBChE contributed up to 90% of the yellow p-nitroaniline product in a standard endotoxin assay through the catalytic hydrolysis of Ac-IEAR-pNA with a rate constant of 0.016 min(-1) and a Km of 2.9 mM in potassium phosphate buffer pH 7.0 at 24 °C. Thus, endotoxin concentrations for native BChE are artificially high in the kinetic chromogenic assay. Destruction of HuBChE catalytic activity by boiling yields endotoxin concentrations that more accurately reflect the endotoxin concentration in purified HuBChE preparations. Copyright © 2016 Elsevier Ireland Ltd. All rights reserved.

Excessive Labeling Technique Provides a Highly Sensitive Fluorescent Probe for Real-time Monitoring of Biodegradation of Biopolymer Pharmaceuticals in vivo.

PubMed

Terekhov, S S; Smirnov, I V; Shamborant, O G; Zenkova, M A; Chernolovskaya, E L; Gladkikh, D V; Murashev, A N; Dyachenko, I A; Knorre, V D; Belogurov, A A; Ponomarenko, N A; Deyev, S M; Vlasov, V V; Gabibov, A G

2014-10-01

Recombinant proteins represent a large sector of the biopharma market. Determination of the main elimination pathways raises the opportunities to significantly increase their half-lives in vivo. However, evaluation of biodegradation of pharmaceutical biopolymers performed in the course of pre-clinical studies is frequently complicated. Noninvasive pharmacokinetic and biodistribution studies in living organism are possible using proteins conjugated with near-infrared dyes. In the present study we designed a highly efficient probe based on fluorescent dye self-quenching for monitoring of in vivo biodegradation of recombinant human butyrylcholinesterase. The maximum enhancement of integral fluorescence in response to degradation of an intravenously administered enzyme was observed 6 h after injection. Importantly, excessive butyrylcholinesterase labeling with fluorescent dye results in significant changes in the pharmacokinetic properties of the obtained conjugate. This fact must be taken into consideration during future pharmacokinetic studies using in vivo bioimaging.

Human butyrylcholinesterase components differ in aryl acylamidase activity.

PubMed

Montenegro, María F; María, T Moral-Naranjo; de la Cadena, María Páez; Campoy, Francisco J; Muñoz-Delgado, Encarnación; Vidal, Cecilio J

2008-04-01

Apart from its esterase activity, butyrylcholinesterase (BuChE) displays aryl acylamidase (AAA) activity able to hydrolyze o-nitroacetanilide (ONA) and its trifluoro-derivative (F-ONA). We report here that, despite amidase and esterase sites residing in the same protein, in human samples depleted of acetylcholinesterase the ratio of amidase to esterase activity varied depending on the source of BuChE. The much faster degradation of ONA and F-ONA by BuChE monomers (G1) of colon and kidney than by the tetramers (G4) suggests aggregation-driven differences in the AAA site between single and polymerized subunits. The similar ratio of F-ONAto butyrylthiocholine hydrolysis by serum G1 and G4 forms support structural differences in the amidase site according to the source of BuChE. The changing ratios of amidase to esterase activities in the human sources probably arise from post-translational modifications in BuChE subunits, the specific proportion of monomers and oligomers and the variable capacity of the tetramers for degrading ONA and F-ONA. The elevated amidase activity of BuChE monomers and the scant activity of the tetramers justify the occurrence of single BuChE subunits in cells as a means to sustain the AAA activity of BuChE which otherwise could be lost by tetramerization.

Identification of phosphorylated butyrylcholinesterase in human plasma using immunoaffinity purification and mass spectrometry

DOE Office of Scientific and Technical Information (OSTI.GOV)

Aryal, Uma K.; Lin, Chiann Tso; Kim, Jong Seo

2012-04-20

Paraoxon (diethyl 4-nitrophenyl phosphate) is an active metabolite of the common insecticide parathion and is acutely toxic due to the inhibition of cholinesterase (ChE) activity in the nervous systems. The Inhibition of butyrylcholinesterase (BChE) activity by paraoxon is due to the formation of phosphorylated BChE adduct, and the detection of the phosphorylated BChE adduct in human plasma can serve as an exposure biomarker of organophosphate pesticides and nerve agents. In this study, we performed immunoaffinity purification and liquid chromatography tandem mass spectrometry (LC-MS/MS) analysis for identifying phosphorylated BChE in human plasma treated by paraoxon. BChE was captured by biotinylated anti-BChEmore » polyclonal antibodies conjugated to streptavidin magnetic beads. Western blot analysis showed that the antibody was effective to recognize both native and modified BChE with high specificity. The exact phosphorylation site of BChE was confirmed on Serine 198 by MS/MS with a 108 Da modification mass and accurately measured parent ion masses. The phosphorylated BChE peptide was also successfully detected in the immunoaffinity purified sample from paraoxon treated human plasma. Thus, immunoaffinity purification combined with mass spectrometry represents a viable approach for the detection of paraoxon-modified BChE and other forms of modified BChE as exposure biomarkers of organophosphates and nerve agents.« less

Biosensor based on Butyrylcholinesterase for Detection of Carbofuran

NASA Astrophysics Data System (ADS)

Dey, Mousumi; Bhuvanagayathri, R.; Daniel, David K.

2015-04-01

Esterase enzymes play an important role in biology because they are responsible for the hydrolysis of choline esters. In their absence, the original state of the post synaptic membranes cannot be reestablished. Therefore, the aim of the work is to study the inhibiting action exerted by the group of compounds on these enzymes. Among these class of inhibiting compounds, pesticides are important because of the potential danger as a result of their large scale use in agriculture. Pesticides are generally determined using liquid or gas chromatography methods with various detection techniques. These methods are very sensitive and discriminating, however they require sample pretreatment such as extraction, preconcentration and clean up, which are skilled techniques and high cost treatment and also time consuming. In this study, acetyl cholinesterase and butyrylcholinesterase based biosensors have emerged as a promising tool for the detection and characterization of pesticides which are inhibitors of these enzymes. Although the physiological function of butyrylcholinesterase in comparison with acetyl cholinesterase is ambiguous, it has larger substrate specificity towards choline esters. Therefore, the development of a more selective electrode against choline, can lead to more sensitive determination of the inhibitor being investigated. Hence in the present work, a method based on inhibition of butyrylcholinesterase was attempted for quantification of carbofuran on the basis of cholinesterase inhibition. Butyrylcholinesterase with an activity of 10.2 units/mg was immobilized on a solid surface by cross linking with glutaraldehyde. The immobilized system was calibrated by correlating the inhibition of the butyrylcholinesterase activity with varying concentrations of the butyryl choline chloride and carbofuran. The sensing mechanism was investigated for its response to carbofuran concentrations ranging from 125 to 1,000 ppm. The effects of butyryl choline chloride concentration on the response of the sensing strip were also determined. Through this work, a sensing element made up of a carbon based electrode, containing the immobilized butyrylcholinesterase, has been described. This element has certain practical advantages like smaller size, user friendly, easy portability and disposability.

Prophylaxis with human serum butyrylcholinesterase protects guinea pigs exposed to multiple lethal doses of soman or VX.

PubMed

Saxena, Ashima; Sun, Wei; Fedorko, James M; Koplovitz, Irwin; Doctor, Bhupendra P

2011-01-01

Human serum butyrylcholinesterase (Hu BChE) is currently under advanced development as a bioscavenger for the prophylaxis of organophosphorus (OP) nerve agent toxicity in humans. It is estimated that a dose of 200mg will be required to protect a human against 2×LD(50) of soman. To provide data for initiating an investigational new drug application for the use of this enzyme as a bioscavenger in humans, we purified enzyme from Cohn fraction IV-4 paste and initiated safety and efficacy evaluations in mice, guinea pigs, and non-human primates. In mice, we demonstrated that a single dose of enzyme that is 30 times the therapeutic dose circulated in blood for at least four days and did not cause any clinical pathology in these animals. In this study, we report the results of safety and efficacy evaluations conducted in guinea pigs. Various doses of Hu BChE delivered by i.m. injections peaked at ∼24h and had a mean residence time of 78-103h. Hu BChE did not exhibit any toxicity in guinea pigs as measured by general observation, serum chemistry, hematology, and gross and histological tissue changes. Efficacy evaluations showed that Hu BChE protected guinea pigs from an exposure of 5.5×LD(50) of soman or 8×LD(50) of VX. These results provide convincing data for the development of Hu BChE as a bioscavenger that can protect humans against all OP nerve agents. Published by Elsevier Inc.

An Enhanced Butyrylcholinesterase Method to Measure Organophosphorus Nerve Agent Exposure in Humans

PubMed Central

Pantazides, Brooke G.; Watson, Caroline M.; Carter, Melissa D.; Crow, Brian S.; Perez, Jonas W.; Blake, Thomas A.; Thomas, Jerry D.; Johnson, Rudolph C.

2016-01-01

Organophosphorus nerve agent (OPNA) adducts to butyrylcholinesterase (BChE) can be used to confirm exposure in humans. A highly accurate method to detect G-series and V-series OPNA adducts to BChE in 75 μL of filtered blood, serum, or plasma has been developed using immunomagnetic separation (IMS) coupled with liquid chromatography tandem mass spectrometry (LC-MS/MS). The reported IMS method captures > 88% of the BChE in a specimen and corrects for matrix effects on peptide calibrators. The optimized method has been used to quantify baseline BChE levels (unadducted and OPNA-adducted) in a matched set of serum, plasma and whole blood (later processed in-house for plasma content) from 192 unexposed individuals to determine the interchangeability of the tested matrices. The results of these measurements demonstrate the ability to accurately measure BChE regardless of the format of the blood specimen received. Criteria for accepting or denying specimens were established through a series of sample stability and processing experiments. The results of these efforts are an optimized and rugged method that is transferrable to other laboratories and an increased understanding of the BChE biomarker in matrix. PMID:24604326

Plasma butyrylcholinesterase regulates ghrelin to control aggression

PubMed Central

Chen, Vicky Ping; Gao, Yang; Geng, Liyi; Parks, Robin J.; Pang, Yuan-Ping; Brimijoin, Stephen

2015-01-01

Ongoing mouse studies of a proposed therapy for cocaine abuse based on viral gene transfer of butyrylcholinesterase (BChE) mutated for accelerated cocaine hydrolysis have yielded surprising effects on aggression. Further investigation has linked these effects to a reduction in circulating ghrelin, driven by BChE at levels ∼100-fold above normal. Tests with human BChE showed ready ghrelin hydrolysis at physiologic concentrations, and multiple low-mass molecular dynamics simulations revealed that ghrelin’s first five residues fit sterically and electrostatically into BChE’s active site. Consistent with in vitro results, male BALB/c mice with high plasma BChE after gene transfer exhibited sharply reduced plasma ghrelin. Unexpectedly, such animals fought less, both spontaneously and in a resident/intruder provocation model. One mutant BChE was found to be deficient in ghrelin hydrolysis. BALB/c mice transduced with this variant retained normal plasma ghrelin levels and did not differ from untreated controls in the aggression model. In contrast, C57BL/6 mice with BChE gene deletion exhibited increased ghrelin and fought more readily than wild-type animals. Collectively, these findings indicate that BChE-catalyzed ghrelin hydrolysis influences mouse aggression and social stress, with potential implications for humans. PMID:25646463

Cholinesterase and Prolyl Oligopeptidase Inhibitory Activities of Alkaloids from Argemone platyceras (Papaveraceae).

PubMed

Siatka, Tomáš; Adamcová, Markéta; Opletal, Lubomír; Cahlíková, Lucie; Jun, Daniel; Hrabinová, Martina; Kuneš, Jiří; Chlebek, Jakub

2017-07-14

Alzheimer's disease is an age-related, neurodegenerative disorder, characterized by cognitive impairment and restrictions in activities of daily living. This disease is the most common form of dementia with complex multifactorial pathological mechanisms. Many therapeutic approaches have been proposed. Among them, inhibition of acetylcholinesterase, butyrylcholinesterase, and prolyl oligopeptidase can be beneficial targets in the treatment of Alzheimer's disease. Roots, along with aerial parts of Argemone platyceras , were extracted with ethanol and fractionated on an alumina column using light petrol, chloroform and ethanol. Subsequently, repeated preparative thin-layer chromatography led to the isolation of (+)-laudanosine, protopine, (-)-argemonine, allocryptopine, (-)-platycerine, (-)-munitagine, and (-)-norargemonine belonging to pavine, protopine and benzyltetrahydroisoquinoline structural types. Chemical structures of the isolated alkaloids were elucidated by optical rotation, spectroscopic and spectrometric analysis (NMR, MS), and comparison with literature data. (+)-Laudanosine was isolated from A. platyceras for the first time. Isolated compounds were tested for human blood acetylcholinesterase, human plasma butyrylcholinesterase and recombinant prolyl oligopeptidase inhibitory activity. The alkaloids inhibited the enzymes in a dose-dependent manner. The most active compound (-)-munitagine, a pavine alkaloid, inhibited both acetylcholinesterase and prolyl oligopeptidase with IC 50 values of 62.3 ± 5.8 µM and 277.0 ± 31.3 µM, respectively.

Synthesis and acetylcholinesterase/butyrylcholinesterase inhibition activity of new tacrine-like analogues.

PubMed

Marco, J L; de los Ríos, C; Carreiras, M C; Baños, J E; Badía, A; Vivas, N M

2001-03-01

The synthesis and preliminary results for acetylcholinesterase and butyrylcholinesterase inhibition activity of a series of pyrano[2,3-b]quinolines (2, 3) and benzonaphthyridines (5, 6) derivatives are described. These molecules are tacrine-like analogues which have been prepared from readily available polyfunctionalized ethyl [6-amino-5-cyano-4H-pyrans and 6-amino-5-cyanopyridines]-3-carboxylates via Friedlander condensation with selected ketones. These compounds showed moderate acetylcholinesterase inhibition activity, the more potent (2e, 5b) being 6 times less active than tacrine. The butyrylcholinesterase activity of some of these molecules is also discussed.

Cholinesterase and Paraoxonase (PON1) enzyme activities in Mexican-American Mothers and Children from an Agricultural Community

PubMed Central

Gonzalez, V.; Huen, K.; Venkat, S.; Pratt, K.; Xiang, P.; Harley, K.G.; Kogut, K.; Trujillo, C.M.; Bradman, A.; Eskenazi, B.; Holland, N.T.

2014-01-01

Exposure to organophosphate and carbamate pesticides can lead to neurotoxic effects through inhibition of cholinesterase enzymes. The paraoxonase (PON1) enzyme can detoxify oxon derivatives of some organophosphates. Lower PON1, acetylcholinesterase, and butyrylcholinesterase activities have been reported in newborns relative to adults, suggesting increased susceptibility to organophosphate exposure in young children. We determined PON1, acetylcholinesterase, and butyrylcholinesterase activities in Mexican-American mothers and their 9-year-old children (n=202 pairs) living in an agricultural community in California. We used paired t-tests to compare enzymatic activities among mothers and their children and analysis of variance to determine which factors are associated with enzyme activities. Substrate-specific PON1 activities were slightly lower in children than their mothers; however, these differences were not statistically significant. We observed significantly lower acetylcholinesterase but higher butyrylcholinesterase levels in children compared to their mothers. Mean butyrylcholinesterase levels were strongly associated with child obesity status (BMI Z scores >95%). We observed highly significant correlations among mother-child pairs for each of the enzymatic activities analyzed; however, PON1 activities did not correlate with acetylcholinesterase or butyrylcholinesterase activities. Our findings suggest that by age nine, PON1 activities approach adult levels and host factors including sex and obesity may affect key enzymes involved in pesticide metabolism. PMID:22760442

Synthesis and biological evaluation of 3-thiazolocoumarinyl Schiff-base derivatives as cholinesterase inhibitors.

PubMed

Raza, Rabia; Saeed, Aamer; Arif, Mubeen; Mahmood, Shamsul; Muddassar, Muhammad; Raza, Ahsan; Iqbal, Jamshed

2012-10-01

On the basis of the observed biological activity of the coumarins, a new set of 3-thiazolocoumarinyl Schiff-base derivatives with chlorine, hydroxy and methoxy functional group substitutions were designed and synthesized. These compounds were tested against acetylcholinesterase from Electrophorus electricus and butyrylcholinesterase from horse serum and their structure-activity relationship was established. Studies revealed them as the potential inhibitors of cholinesterase (acetylcholinesterase and butyrylcholinesterase). The 3f was found to be most potent against acetylcholinesterase with K(i) value of 1.05 ± 0.3 μM and 3l showed excellent inhibitory action against butyrylcholinesterase with K(i) value of 0.041 ± 0.002 μM. The synthesized compounds were also docked into the active sites of the homology models of acetylcholinesterase and butyrylcholinesterase to predict the binding modes of these compounds. It was predicted that most of the compounds have similar binding modes with reasonable binding affinities. Our docking studies have also shown that these synthesized compounds have better interaction patterns with butyrylcholinesterase over acetylcholinesterase. The main objective of the study was to develop new potent and selective compounds, which might be further optimized to prevent the progression of the Alzheimer's disease and could provide symptomatic treatment. © 2012 John Wiley & Sons A/S.

Tetramer-organizing polyproline-rich peptides differ in CHO cell-expressed and plasma-derived human butyrylcholinesterase tetramers.

PubMed

Schopfer, Lawrence M; Lockridge, Oksana

2016-06-01

Tetrameric butyrylcholinesterase (BChE) in human plasma is the product of multiple genes, namely one BCHE gene on chromosome 3q26.1 and multiple genes that encode polyproline-rich peptides. The function of the polyproline-rich peptides is to assemble BChE into tetramers. CHO cells transfected with human BChE cDNA express BChE monomers and dimers, but only low quantities of tetramers. Our goal was to identify the polyproline-rich peptides in CHO-cell derived human BChE tetramers. CHO cell-produced human BChE tetramers were purified from serum-free culture medium. Peptides embedded in the tetramerization domain were released from BChE tetramers by boiling and identified by liquid chromatography-tandem mass spectrometry. A total of 270 proline-rich peptides were sequenced, ranging in size from 6-41 residues. The peptides originated from 60 different proteins that reside in multiple cell compartments including the nucleus, cytoplasm, and endoplasmic reticulum. No single protein was the source of the polyproline-rich peptides in CHO cell-expressed human BChE tetramers. In contrast, 70% of the tetramer-organizing peptides in plasma-derived BChE tetramers originate from lamellipodin. No protein source was identified for polyproline peptides containing up to 41 consecutive proline residues. In conclusion, the use of polyproline-rich peptides as a tetramerization motif is documented only for the cholinesterases, but is expected to serve other tetrameric proteins as well. The CHO cell data suggest that the BChE tetramer-organizing peptide can arise from a variety of proteins. Copyright © 2016 Elsevier B.V. All rights reserved.

In vitro sensitivity of cholinesterases and [3H]oxotremorine-M binding in heart and brain of adult and aging rats to organophosphorus anticholinesterases.

PubMed

Mirajkar, Nikita; Pope, Carey N

2008-10-15

Organophosphorus (OP) insecticides elicit toxicity via acetylcholinesterase inhibition, allowing acetylcholine accumulation and excessive stimulation of cholinergic receptors. Some OP insecticides bind to additional macromolecules including butyrylcholinesterase and cholinergic receptors. While neurotoxicity from OP anticholinesterases has been extensively studied, effects on cardiac function have received less attention. We compared the in vitro sensitivity of acetylcholinesterase, butyrylcholinesterase and [(3)H]oxotremorine-M binding to muscarinic receptors in the cortex and heart of adult (3 months) and aging (18 months) rats to chlorpyrifos, methyl parathion and their active metabolites chlorpyrifos oxon and methyl paraoxon. Using selective inhibitors, the great majority of cholinesterase in brain was defined as acetylcholinesterase, while butyrylcholinesterase was the major cholinesterase in heart, regardless of age. In the heart, butyrylcholinesterase was markedly more sensitive than acetylcholinesterase to inhibition by chlorpyrifos oxon, and butyrylcholinesterase in tissues from aging rats was more sensitive than enzyme from adults, possibly due to differences in A-esterase mediated detoxification. Relatively similar differences were noted in brain. In contrast, acetylcholinesterase was more sensitive than butyrylcholinesterase to methyl paraoxon in both heart and brain, but no age-related differences were noted. Both oxons displaced [(3)H]oxotremorine-M binding in heart and brain of both age groups in a concentration-dependent manner. Chlorpyrifos had no effect but methyl parathion was a potent displacer of binding in heart and brain of both age groups. Such OP and age-related differences in interactions with cholinergic macromolecules may be important because of potential for environmental exposures to insecticides as well as the use of anticholinesterases in age-related neurological disorders.

IN VITRO SENSITIVITY OF CHOLINESTERASES AND [3H]OXOTREMORINE-M BINDING IN HEART AND BRAIN OF ADULT AND AGING RATS TO ORGANOPHOSPHORUS ANTICHOLINESTERASES

PubMed Central

Mirajkar, Nikita; Pope, Carey N.

2008-01-01

Organophosphorus (OP) insecticides elicit toxicity via acetylcholinesterase inhibition, allowing acetylcholine accumulation and excessive stimulation of cholinergic receptors. Some OP insecticides bind to additional macromolecules including butyrylcholinesterase and cholinergic receptors. While neurotoxicity from OP anticholinesterases has been extensively studied, effects on cardiac function have received less attention. We compared the in vitro sensitivity of acetylcholinesterase, butyrylcholinesterase and [3H]oxotremorine-M binding to muscarinic receptors in the cortex and heart of adult (3 months) and aging (18 months) rats to chlorpyrifos, methyl parathion and their active metabolites chlorpyrifos oxon and methyl paraoxon. Using selective inhibitors, the great majority of cholinesterase in brain was defined as acetylcholinesterase, while butyrylcholinesterase was the major cholinesterase in heart, regardless of age. In the heart, butyrylcholinesterase was markedly more sensitive than acetylcholinesterase to inhibition by chlorpyrifos oxon, and butyrylcholinesterase in tissues from aging rats was more sensitive than enzyme from adults, possibly due to differences in A-esterase mediated detoxification. Relatively similar differences were noted in brain. In contrast, acetylcholinesterase was more sensitive than butyrylcholinesterase to methyl paraoxon in both heart and brain, but no age-related differences were noted. Both oxons displaced [3H]oxotremorine-M binding in heart and brain of both age groups in a concentration-dependent manner. Chlorpyrifos had no effect but methyl parathion was a potent displacer of binding in heart and brain of both age groups. Such OP and age-related differences in interactions with cholinergic macromolecules may be important because of potential for environmental exposures to insecticides as well as the use of anticholinesterases in age-related neurological disorders. PMID:18761328

In vitro ability of currently available oximes to reactivate organophosphate pesticide-inhibited human acetylcholinesterase and butyrylcholinesterase.

PubMed

Jun, Daniel; Musilova, Lucie; Musilek, Kamil; Kuca, Kamil

2011-01-01

We have in vitro tested the ability of common, commercially available, cholinesterase reactivators (pralidoxime, obidoxime, methoxime, trimedoxime and HI-6) to reactivate human acetylcholinesterase (AChE), inhibited by five structurally different organophosphate pesticides and inhibitors (paraoxon, dichlorvos, DFP, leptophos-oxon and methamidophos). We also tested reactivation of human butyrylcholinesterase (BChE) with the aim of finding a potent oxime, suitable to serve as a "pseudocatalytic" bioscavenger in combination with this enzyme. Such a combination could allow an increase of prophylactic and therapeutic efficacy of the administered enzyme. According to our results, the best broad-spectrum AChE reactivators were trimedoxime and obidoxime in the case of paraoxon, leptophos-oxon, and methamidophos-inhibited AChE. Methamidophos and leptophos-oxon were quite easily reactivatable by all tested reactivators. In the case of methamidophos-inhibited AChE, the lower oxime concentration (10(-5) M) had higher reactivation ability than the 10(-4) M concentration. Therefore, we evaluated the reactivation ability of obidoxime in a concentration range of 10(-3)-10(-7) M. The reactivation of methamidophos-inhibited AChE with different obidoxime concentrations resulted in a bell shaped curve with maximum reactivation at 10(-5) M. In the case of BChE, no reactivator exceeded 15% reactivation ability and therefore none of the oximes can be recommended as a candidate for "pseudocatalytic" bioscavengers with BChE.

Generation and Evaluation of PEGylated Recombinant Human Acetylcholinesterase as an Optimal OP-Bioscavenger

DTIC Science & Technology

2009-04-27

intramuscularly and then monitored at various time points for body weight and temperature, blood glucose levels, blood biochemistry and hematology. No...means for therapeutic treatment of OP compound poisoning without exerting any deleterious effect on the treated subjects...R.P., Castro, C.A., Finger, A.V. and Lenz, D.E. (1991). Protection by butyrylcholinesterase against organophosphorus poisoning in nonhuman primates

Protein tyrosine adduct in humans self-poisoned by chlorpyrifos

DOE Office of Scientific and Technical Information (OSTI.GOV)

Li, Bin, E-mail: binli@unmc.edu; Eyer, Peter, E-mail: peter.eyer@lrz.uni-muenchen.de; Eddleston, Michael, E-mail: M.Eddleston@ed.ac.uk

2013-06-15

Studies of human cases of self-inflicted poisoning suggest that chlorpyrifos oxon reacts not only with acetylcholinesterase and butyrylcholinesterase but also with other blood proteins. A favored candidate is albumin because in vitro and animal studies have identified tyrosine 411 of albumin as a site covalently modified by organophosphorus poisons. Our goal was to test this proposal in humans by determining whether plasma from humans poisoned by chlorpyrifos has adducts on tyrosine. Plasma samples from 5 self-poisoned humans were drawn at various time intervals after ingestion of chlorpyrifos for a total of 34 samples. All 34 samples were analyzed for plasmamore » levels of chlorpyrifos and chlorpyrifos oxon (CPO) as a function of time post-ingestion. Eleven samples were analyzed for the presence of diethoxyphosphorylated tyrosine by mass spectrometry. Six samples yielded diethoxyphosphorylated tyrosine in pronase digests. Blood collected as late as 5 days after chlorpyrifos ingestion was positive for CPO-tyrosine, consistent with the 20-day half-life of albumin. High plasma CPO levels did not predict detectable levels of CPO-tyrosine. CPO-tyrosine was identified in pralidoxime treated patients as well as in patients not treated with pralidoxime, indicating that pralidoxime does not reverse CPO binding to tyrosine in humans. Plasma butyrylcholinesterase was a more sensitive biomarker of exposure than adducts on tyrosine. In conclusion, chlorpyrifos oxon makes a stable covalent adduct on the tyrosine residue of blood proteins in humans who ingested chlorpyrifos. - Highlights: • Chlorpyrifos-poisoned patients have adducts on protein tyrosine. • Diethoxyphosphate-tyrosine does not lose an alkyl group. • Proteins in addition to AChE and BChE are modified by organophosphates.« less

Expression of Membrane-Bound Human AminopeptidaseP as a Soluble Enzyme and an Investigation into Its Efficacy Towards Offering Protection Against the Toxicity of Chemical Warfare Nerve Agents

DTIC Science & Technology

2016-09-01

survival rate of guinea pigs from GF toxicity [31]. The overall catalytic efficiency of II-G1 reported by Worek against GF was 8.4 × 107 M-1 min-1 and...al., Protection against soman or VX poisoning by human butyrylcholinesterase in guinea pigs and cynomolgus monkeys. Chem Biol Interact, 2005. 157...97-102. 30. Valiyaveettil, M., et al., Protective efficacy of catalytic bioscavenger, paraoxonase 1 against sarin and soman exposure in guinea pigs

Molecular Probe Analysis of Mammalian Brain Acetylcholinesterase

DTIC Science & Technology

1988-09-27

Project and Degrees Awarded During this Reporting Period: Judith K. Marquis, Principal Investigator Thomas Biagioni , Senior Research Technician Robert...binding sites in nerve membrane vesicles. Comp. Biochem. Physiol. 80C: 203-205 (1985). 5. Volpe, L.S., T.M. Biagioni & J.K. Marquis: In vitro modulation of...Saxena, Vol. 6(1988Y.8 11. Marquis, J.K. & T.M. Biagioni : Selective inhibition of acetylcholinesterase and butyrylcholinesterase in human plasma

Surrogate markers of the kidney and liver in the assessment of gestational diabetes mellitus and fetal outcome.

PubMed

Liu, Hong; Shao-Gang, Ma; Liang, Cheng; Feng, Bai; Wei, Xu

2015-01-01

To investigate whether serum levels of butyrylcho-linesterase activity, cystatin C, and pre-albumin has the potential value as γ-glutamyl transferase in reflecting gestational diabetes mellitus and its fetal outcome. Seventy-six gestational diabetes mellitus women and 76 pregnancies with normal glucose tolerance in the second trimester were enrolled. Maternal serum parameters of butyrylcholinesterase activity, γ-glutamyl transferase, cystatin C, and pre-albumin were detected and evaluated. The pregnant complications and fetal outcome were also evaluated. Levels of butyrylcholinesterase activity, γ-glutamyl transferase, cystatin C, pre-albumin and glycemic variables were higher in the gestational diabetes mellitus patients than in the controls. Levels of butyrylcholinesterase activity were significantly correlated to the levels of fasting plasma glucose, cystatin C, and γ- glutamyl transferase (p < 0.05) in the gestational diabetes mellitus group. There were statistical differences in cases of preterm delivery, preeclampsia and postpartum hemorrhage. Higher levels of γ-glutamyl transferase and pre-albumin were risk markers for gestational diabetes mellitus (p < 0.05). The diagnosis curve demonstrated that γ-glutamyl transferase had a significant advantage over other markers (p < 0.001) but no significance compared with pre-albumin (p = 0.096). None of the detected markers showed predictive value for fetal outcome. Serum levels of butyrylcholinesterase activity, γ-glutamyl transferase, cystatin C and pre-albumin were correlated with gestational diabetes mellitus status but not with the fetal outcome. Pre-albumin can be equivalent as γ-glutamyl transferase in reflecting the presence of gestational diabetes mellitus.

In Vitro Ability of Currently Available Oximes to Reactivate Organophosphate Pesticide-Inhibited Human Acetylcholinesterase and Butyrylcholinesterase

PubMed Central

Jun, Daniel; Musilova, Lucie; Musilek, Kamil; Kuca, Kamil

2011-01-01

We have in vitro tested the ability of common, commercially available, cholinesterase reactivators (pralidoxime, obidoxime, methoxime, trimedoxime and HI-6) to reactivate human acetylcholinesterase (AChE), inhibited by five structurally different organophosphate pesticides and inhibitors (paraoxon, dichlorvos, DFP, leptophos-oxon and methamidophos). We also tested reactivation of human butyrylcholinesterase (BChE) with the aim of finding a potent oxime, suitable to serve as a “pseudocatalytic” bioscavenger in combination with this enzyme. Such a combination could allow an increase of prophylactic and therapeutic efficacy of the administered enzyme. According to our results, the best broad-spectrum AChE reactivators were trimedoxime and obidoxime in the case of paraoxon, leptophos-oxon, and methamidophos-inhibited AChE. Methamidophos and leptophos-oxon were quite easily reactivatable by all tested reactivators. In the case of methamidophos-inhibited AChE, the lower oxime concentration (10−5 M) had higher reactivation ability than the 10−4 M concentration. Therefore, we evaluated the reactivation ability of obidoxime in a concentration range of 10−3–10−7 M. The reactivation of methamidophos-inhibited AChE with different obidoxime concentrations resulted in a bell shaped curve with maximum reactivation at 10−5 M. In the case of BChE, no reactivator exceeded 15% reactivation ability and therefore none of the oximes can be recommended as a candidate for “pseudocatalytic” bioscavengers with BChE. PMID:21673941

Distinct Effect of Benzalkonium Chloride on the Esterase and Aryl Acylamidase Activities of Butyrylcholinesterase.

PubMed

Jaganathan; Boopathy

2000-08-01

Acetylcholinesterase (AChE) and butyrylcholinesterase (BChE) from vertebrates, other than their predominant acylcholine hydrolase (esterase) activity, display a genuine aryl acylamidase activity (AAA) capable of hydrolyzing the synthetic substrate o-nitroacetanilide to o-nitroaniline. This AAA activity is strongly inhibited by classical cholinesterase (ChE) inhibitors. In the present study, benzalkonium chloride (BAC), a cationic detergent widely used as a preservative in pharmaceutical preparations, has been shown to distinctly modulate the esterase and AAA activities of BChEs. The detergent BAC was able to inhibit the esterase activity of human serum and horse serum BChEs and AChEs from electric eel and human erythrocyte. The remarkable property of BAC was its ability to profoundly activate the AAA activity of human serum and horse serum BChEs but not the AAA activity of AChEs. Thus BAC seem to preferentially activate the AAA activity of BChEs alone. Results of the study using the ChE active site-specific inhibitor diisopropyl phosphorofluoridate indicated that BAC binds to the active site of ChEs. Furthermore, studies using a structural homolog of BAC indicated that the alkyl group of BAC is essential not only for its interaction with ChEs but also for its distinct effect on the esterase and AAA activities of BChEs. This is the first report of a compound that inhibits the esterase activity, while simultaneously activating the AAA activity, of BChEs. Copyright 2000 Academic Press.

Quantitation of ortho-Cresyl Phosphate Adducts to Butyrylcholinesterase in Human Serum by Immunomagnetic-UHPLC-MS/MS

PubMed Central

Johnson, Darryl; Carter, Melissa D.; Crow, Brian S.; Isenberg, Samantha L.; Graham, Leigh Ann; Erol, H. Akin; Watson, Caroline M.; Pantazides, Brooke G.; van der Schans, Marcel J.; Langenberg, Jan P.; Noort, Daan; Blake, Thomas A.; Thomas, Jerry D.; Johnson, Rudolph C.

2017-01-01

Tri-ortho-cresyl phosphate (ToCP) is an anti-wear, flame retardant additive used in industrial lubricants, hydraulic fluids, and gasoline. The neurotoxic effects of ToCP arise from the liver-activated metabolite 2-(o-cresyl)-4H-1,3,2-benzodioxaphosphoran-2-one (cresyl saligenin phosphate or CBDP), which inhibits esterase enzymes including butyrylcholinesterase (BChE). Following BChE adduction, CBDP undergoes hydrolysis to form the aged adduct ortho-cresyl phosphoserine (oCP-BChE), thus providing a biomarker of CBDP exposure. Previous studies have identified ToCP in aircraft cabin and cockpit air, but assessing human exposure has been hampered by the lack of a laboratory assay to confirm exposure. This work presents the development of an immunomagnetic-UHPLC-MS/MS method for the quantitation of unadducted BChE and the long-term CBDP biomarker, oCP-BChE, in human serum. The method has a reportable range from 2.0 ng/mL to 150 ng/mL, which is consistent with the sensitivity of methods used to detect organophosphorus nerve agent protein adducts. The assay demonstrated high intraday and interday accuracy (≥ 85%) and precision (RSD ≤ 15%) across the calibration range. The method was developed for future analyses of potential human exposure to CBDP. Analysis of human serum inhibited in vitro with CBDP demonstrated that the oCP-BChE adduct was stable for at least 72 hours at 4, 22 and 37 °C. Compared to a previously reported assay, this method requires 75% less sample volume, reduces analysis time by a factor of 20, and demonstrates a 3-fold improvement in sensitivity. PMID:26149113

Catalytic Bioscavengers Human Butyrylcholinesterase and Paraoxonase Sequestered to the Center for CNS

DTIC Science & Technology

2010-04-01

of radiolabeling fusion proteins without the denaturing effects coincident with oxidative radio-iodination associated with the chloramine T method...organ PS product = [(%ID/g)/AUC]*1000 Reportable Outcomes (1) The plasma concentration decay curve for AGT-185 is shown in Figure 1. The % of...injected dose (ID)/mL decreases rapidly in plasma following IV injection. This plasma decay curve was fit to the bi-exponential equation described above

Biochemical Markers for Exposure to Low Doses of Organophosphorus Insecticides

DTIC Science & Technology

2005-08-01

Rodriguez OP, Muth GW, Berkman CE, Kim K and Thompson CM (1997) Inhibition of various cholinesterases with the enantiomers of malaoxon. Bull Environ Contain...including diazepam (Fehskc et aL., phylated human butyrylcholinesterase. Chem. Res. Toxicol. 15, 582-590. 1979; Peters, 1996) and ibuprofen , bind to the...dose of diazepam or ibuprofen . Or conver- Hui, D. M., and Minami, M. (2000). Monitoring of fluorine in urine samples ofpatients involved in the Tokyo

Synthesis and in vitro acetylcholinesterase and butyrylcholinesterase inhibitory potential of hydrazide based Schiff bases.

PubMed

Rahim, Fazal; Ullah, Hayat; Taha, Muhammad; Wadood, Abdul; Javed, Muhammad Tariq; Rehman, Wajid; Nawaz, Mohsan; Ashraf, Muhammad; Ali, Muhammad; Sajid, Muhammad; Ali, Farman; Khan, Muhammad Naseem; Khan, Khalid Mohammed

2016-10-01

To discover multifunctional agents for the treatment of Alzheimer's disease, a series of hydrazide based Schiff bases were designed and synthesized based on multitarget-directed strategy. We have synthesized twenty-eight analogs of hydrazide based Schiff bases, characterized by various spectroscopic techniques and evaluated in vitro for acetylcholinesterase and butyrylcholinesterase inhibition. All compounds showed varied degree of acetylcholinesterase and butyrylcholinesterase inhibition when compared with standard Eserine. Among the series, compounds 10, 3 and 24 having IC50 values 4.12±0.01, 8.12±0.01 and 8.41±0.06μM respectively showed potent acetylcholinesterase inhibition when compared with Eserine (IC50=0.85±0.0001μM). Three compounds 13, 24 and 3 having IC50 values 6.51±0.01, 9.22±0.07 and 37.82±0.14μM respectively showed potent butyrylcholinesterase inhibition by comparing with eserine (IC50=0.04±0.0001μM). The remaining compounds also exhibited moderate to weak inhibitory potential. Structure activity relationship has been established. Through molecular docking studies the binding interaction was confirmed. Copyright © 2016 Elsevier Inc. All rights reserved.

Amyloid-β peptides act as allosteric modulators of cholinergic signalling through formation of soluble BAβACs

PubMed Central

Kumar, Rajnish; Nordberg, Agneta

2016-01-01

Abstract Amyloid-β peptides, through highly sophisticated enzymatic machinery, are universally produced and released in an action potential synchronized manner into the interstitial fluids in the brain. Yet no native functions are attributed to amyloid-β. The amyloid-β hypothesis ascribes just neurotoxicity properties through build-up of soluble homomeric amyloid-β oligomers or fibrillar deposits. Apolipoprotein-ε4 (APOE4) allele is the only confirmed genetic risk factor of sporadic Alzheimer’s disease; once more it is unclear how it increases the risk of Alzheimer’s disease. Similarly, central cholinergic signalling is affected selectively and early in the Alzheimer’s disease brain, again why cholinergic neurons show this sensitivity is still unclear. However, the three main known Alzheimer’s disease risk factors, advancing age, female gender and APOE4, have been linked to a high apolipoprotein-E and accumulation of the acetylcholine degrading enzyme, butyrylcholinesterase in cerebrospinal fluids of patients. Furthermore, numerous reports indicate that amyloid-β interacts with butyrylcholinesterase and apolipoprotein-E. We have proposed that this interaction leads to formation of soluble ultrareactive acetylcholine-hydrolyzing complexes termed BAβACs, to adjust at demand both synaptic and extracellular acetylcholine signalling. This hypothesis predicted presence of acetylcholine-synthesizing enzyme, choline acetyltransferase in extracellular fluids to allow maintenance of equilibrium between breakdown and synthesis of acetylcholine through continuous in situ syntheses. A recent proof-of-concept study led to the discovery of this enzyme in the human extracellular fluids. We report here that apolipoprotein-E, in particular ε4 isoprotein acts as one of the strongest endogenous anti-amyloid-β fibrillization agents reported in the literature. At biological concentrations, apolipoprotein-E prevented amyloid-β fibrillization for at least 65 h. We show that amyloid-β interacts readily in an apolipoprotein-facilitated manner with butyrylcholinesterase, forming highly stable and soluble complexes, BAβACs, which can be separated in their native states by sucrose density gradient technique. Enzymological analyses further evinced that amyloid-β concentration dependently increased the acetylcholine-hydrolyzing capacity of cholinesterases. In silico biomolecular analysis further deciphered the allosteric amino acid fingerprint of the amyloid-β-cholinesterase molecular interaction in formation of BAβACs. In the case of butyrylcholinesterase, the results indicated that amyloid-β interacts with a putative activation site at the mouth of its catalytic tunnel, most likely leading to increased acetylcholine influx into the catalytic site, and thereby increasing the intrinsic catalytic rate of butyrylcholinesterase. In conclusion, at least one of the native physiological functions of amyloid-β is allosteric modulation of the intrinsic catalytic efficiency of cholinesterases, and thereby regulation of synaptic and extrasynaptic cholinergic signalling. High apolipoprotein-E may pathologically alter the biodynamics of this amyloid-β function. PMID:26525916

A Novel Way To Radiolabel Human Butyrylcholinesterase for Positron Emission Tomography through Irreversible Transfer of the Radiolabeled Moiety.

PubMed

Sawatzky, Edgar; Al-Momani, Ehab; Kobayashi, Ryohei; Higuchi, Takahiro; Samnick, Samuel; Decker, Michael

2016-07-19

The enzyme butyrylcholinesterase (BChE) is known to be involved in the detoxification of xenobiotics in blood plasma and is associated with the progress of neurodegenerative disorders, diabetes type 2, obesity, and diseases of the cardiovascular system. In the present study, we developed carbamate-based inhibitors serving as positron emission tomography (PET) radiotracers with (18) F and (11) C as radioisotopes to visualize BChE distribution. These inhibitors are radiolabeled at the carbamate site and transfer this moiety onto BChE, which thus results in covalent and permanent radiolabeling of the enzyme. There are no comparable radiotracers for cholinesterases described to date. By ex vivo autoradiography experiments on mice brain slices and kinetic investigations, selective and covalent transfer of the radiolabeled carbamate moiety onto BChE was proven. These tracers might provide high resolution of BChE distribution in vivo to enable investigations into the pathophysiological mechanisms of diseases associated with alterations in BChE occurrence. © 2016 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

Novel donepezil-based inhibitors of acetyl- and butyrylcholinesterase and acetylcholinesterase-induced beta-amyloid aggregation.

PubMed

Camps, Pelayo; Formosa, Xavier; Galdeano, Carles; Gómez, Tània; Muñoz-Torrero, Diego; Scarpellini, Michele; Viayna, Elisabet; Badia, Albert; Clos, M Victòria; Camins, Antoni; Pallàs, Mercè; Bartolini, Manuela; Mancini, Francesca; Andrisano, Vincenza; Estelrich, Joan; Lizondo, Mònica; Bidon-Chanal, Axel; Luque, F Javier

2008-06-26

A novel series of donepezil-tacrine hybrids designed to simultaneously interact with the active, peripheral and midgorge binding sites of acetylcholinesterase (AChE) have been synthesized and tested for their ability to inhibit AChE, butyrylcholinesterase (BChE), and AChE-induced A beta aggregation. These compounds consist of a unit of tacrine or 6-chlorotacrine, which occupies the same position as tacrine at the AChE active site, and the 5,6-dimethoxy-2-[(4-piperidinyl)methyl]-1-indanone moiety of donepezil (or the indane derivative thereof), whose position along the enzyme gorge and the peripheral site can be modulated by a suitable tether that connects tacrine and donepezil fragments. All of the new compounds are highly potent inhibitors of bovine and human AChE and BChE, exhibiting IC50 values in the subnanomolar or low nanomolar range in most cases. Moreover, six out of the eight hybrids of the series, particularly those bearing an indane moiety, exhibit a significant A beta antiaggregating activity, which makes them promising anti-Alzheimer drug candidates.

Differential sensitivity of plasma carboxylesterase-null mice to parathion, chlorpyrifos and chlorpyrifos oxon, but not to diazinon, dichlorvos, diisopropylfluorophosphate, cresyl saligenin phosphate, cyclosarin thiocholine, tabun thiocholine, and carbofuran

PubMed Central

Duysen, Ellen G.; Cashman, John R.; Schopfer, Lawrence M.; Nachon, Florian; Masson, Patrick; Lockridge, Oksana

2012-01-01

Mouse blood contains four esterases that detoxify organophosphorus compounds: carboxylesterase, butyrylcholinesterase, acetylcholinesterase, and paraoxonase-1. In contrast human blood contains the latter three enzymes but not carboxylesterase. Organophosphorus compound toxicity is due to inhibition of acetylcholinesterase. Symptoms of intoxication appear after approximately 50% of the acetylcholinesterase is inhibited. However, complete inhibition of carboxylesterase and butyrylcholinesterase has no known effect on an animal’s well being. Paraoxonase hydrolyzes organophosphorus compounds and is not inhibited by them. Our goal was to determine the effect of plasma carboxylesterase deficiency on response to sublethal doses of 10 organophosphorus toxicants and one carbamate pesticide. Homozygous plasma carboxylesterase deficient ES1−/− mice and wild-type littermates were observed for toxic signs and changes in body temperature after treatment with a single sublethal dose of toxicant. Inhibition of plasma acetylcholinesterase, butyrylcholinesterase, and plasma carboxylesterase was measured. It was found that wild-type mice were protected from the toxicity of 12.5 mg/kg parathion applied subcutaneously. However, both genotypes responded similarly to paraoxon, cresyl saligenin phosphate, diisopropylfluorophosphate, diazinon, dichlorvos, cyclosarin thiocholine, tabun thiocholine, and carbofuran. An unexpected result was the finding that transdermal application of chlorpyrifos at 100 mg/kg and chlorpyrifos oxon at 14 mg/kg was lethal to wild-type but not to ES1−/− mice, showing that with this organochlorine, the presence of carboxylesterase was harmful rather than protective. It was concluded that carboxylesterase in mouse plasma protects from high toxicity agents, but the amount of carboxylesterase in plasma is too low to protect from low toxicity compounds that require high doses to inhibit acetylcholinesterase. PMID:22209767

Production of Polyclonal Antibodies in Rabbits

DTIC Science & Technology

1995-10-01

injections of bovine fetal serum acetylcholinesterase and horse serum butyrylcholinesterase in rabbits. Concentrations of these enzymes became...13 2. Horse Serum Butyrylcholinesterase (E-BChE) 14 3. Bovine Serum Albumin (BSA) and Rabbit Serum Al4umin (RSA) 14 4. Suppocire-D 14 5. Triglyceride...Extraction from Calcium Sulfate Microspheres 16 c. Removal of Sealant and Polymer Overcoat from Calcium 17 Sulfate Microspheres 5. Size Distribution 17 6. In

Delipidation of Plasma Has Minimal Effects on Human Butyrylcholinesterase.

PubMed

Onder, Seda; Tacal, Ozden; Lockridge, Oksana

2018-01-01

Human butyrylcholinesterase (BChE) is purified in large quantities from Cohn fraction IV-4 to use for protection against the toxicity of chemical warfare agents. Small scale preliminary experiments use outdated plasma from the American Red Cross as the starting material for purifying BChE (P06276). Many of the volunteer donor plasma samples are turbid with fat, the donor having eaten fatty food before the blood draw. The turbid fat interferes with enzyme assays performed in the spectrophotometer and with column chromatography. Our goal was to find a method to remove fat from plasma without loss of BChE activity. Satisfactory delipidation was achieved by adding a solution of 10% dextran sulfate and calcium chloride to fatty plasma, followed by centrifugation, and filtration through a 0.8 μm filter. Treatment with Aerosil also delipidated fatty plasma, but was accompanied by loss of 50% of the plasma volume. BChE activity and the BChE isozyme pattern on nondenaturing gel electrophoresis were unaffected by delipidation. BChE in delipidated plasma was efficiently captured by immobilized monoclonal antibodies B2 18-5 and mAb2. The immunopurified BChE was released from antibody binding with acid and visualized as a highly enriched, denatured BChE preparation by SDS gel electrophoresis. In conclusion, delipidation with dextran sulfate/CaCl 2 preserves BChE activity and the tetramer structure of BChE.

A systematic review on human exposure to organophosphorus pesticides in Iran.

PubMed

Shadboorestan, Amir; Vardanjani, Hossein Molavi; Abdollahi, Mohammad; Goharbari, Mohammad Hadi; Khanjani, Narges

2016-07-02

Human exposure to organophosphorus (OP) pesticides is a serious health challenge. We conducted a systematic review by searching international and national databases for published literature on any human exposure to OPs in Iran from 1990 to March 2015. Qualified papers were in two categories including studies in which biomarkers of exposure were assessed (n = 13; total no. of subjects = 759) and studies that had reported prevalence of OPs-induced poisoning (OPP) and mortality (n = 26; total no. of subjects = 5428). The mean level of activity of acetyl-cholinesterase and butyryl-cholinesterase were 68.65% and 74.2%, respectively. Overall proportion (%) of OPP was estimated (16; 95% CI, 14 to 19).

Exposure to tri-o-cresyl phosphate detected in jet airplane passengers.

PubMed

Liyasova, Mariya; Li, Bin; Schopfer, Lawrence M; Nachon, Florian; Masson, Patrick; Furlong, Clement E; Lockridge, Oksana

2011-11-01

The aircraft cabin and flight deck ventilation are supplied from partially compressed unfiltered bleed air directly from the engine. Worn or defective engine seals can result in the release of engine oil into the cabin air supply. Aircrew and passengers have complained of illness following such "fume events". Adverse health effects are hypothesized to result from exposure to tricresyl phosphate mixed esters, a chemical added to jet engine oil and hydraulic fluid for its anti-wear properties. Our goal was to develop a laboratory test for exposure to tricresyl phosphate. The assay was based on the fact that the active-site serine of butyrylcholinesterase reacts with the active metabolite of tri-o-cresyl phosphate, cresyl saligenin phosphate, to make a stable phosphorylated adduct with an added mass of 80 Da. No other organophosphorus agent makes this adduct in vivo on butyrylcholinesterase. Blood samples from jet airplane passengers were obtained 24-48 h after completing a flight. Butyrylcholinesterase was partially purified from 25 ml serum or plasma, digested with pepsin, enriched for phosphorylated peptides by binding to titanium oxide, and analyzed by mass spectrometry. Of 12 jet airplane passengers tested, 6 were positive for exposure to tri-o-cresyl phosphate that is, they had detectable amounts of the phosphorylated peptide FGEpSAGAAS. The level of exposure was very low. No more than 0.05 to 3% of plasma butyrylcholinesterase was modified. None of the subjects had toxic symptoms. Four of the positive subjects were retested 3 to 7 months following their last airplane trip and were found to be negative for phosphorylated butyrylcholinesterase. In conclusion, this is the first report of an assay that detects exposure to tri-o-cresyl phosphate in jet airplane travelers. Copyright © 2011 Elsevier Inc. All rights reserved.

Exposure to tri-o-cresyl phosphate detected in jet airplane passengers

PubMed Central

Liyasova, Mariya; Li, Bin; Schopfer, Lawrence M.; Nachon, Florian; Masson, Patrick; Furlong, Clement E.; Lockridge, Oksana

2011-01-01

The aircraft cabin and flight deck ventilation are supplied from partially compressed unfiltered bleed air directly from the engine. Worn or defective engine seals can result in the release of engine oil into the cabin air supply. Aircrew and passengers have complained of illness following such “fume events”. Adverse health effects are hypothesized to result from exposure to tricresyl phosphate mixed esters, a chemical added to jet engine oil and hydraulic fluid for its anti-wear properties. Our goal was to develop a laboratory test for exposure to tricresyl phosphate. The assay was based on the fact that the active-site serine of butyrylcholinesterase reacts with the active metabolite of tri-o-cresyl phosphate, cresyl saligenin phosphate, to make a stable phosphorylated adduct with an added mass of 80 Da. No other organophosphorus agent makes this adduct in vivo on butyrylcholinesterase. Blood samples from jet airplane passengers were obtained 24–48 hours after completing a flight. Butyrylcholinesterase was partially purified from 25 ml serum or plasma, digested with pepsin, enriched for phosphorylated peptides by binding to titanium oxide, and analyzed by mass spectrometry. Of 12 jet airplane passengers tested, 6 were positive for exposure to tri-o-cresyl phosphate that is, they had detectable amounts of the phosphorylated peptide FGEpSAGAAS. The level of exposure was very low. No more than 0.05 to 3% of plasma butyrylcholinesterase was modified. None of the subjects had toxic symptoms. Four of the positive subjects were retested 3 to 7 months following their last airplane trip and were found to be negative for phosphorylated butyrylcholinesterase. In conclusion, this is the first report of an assay that detects exposure to tri-o-cresyl phosphate in jet airplane travelers. PMID:21723309

Synthesis and Preliminary Evaluation of Phenyl 4-123I-Iodophenylcarbamate for Visualization of Cholinesterases Associated with Alzheimer Disease Pathology.

PubMed

Macdonald, Ian R; Reid, G Andrew; Pottie, Ian R; Martin, Earl; Darvesh, Sultan

2016-02-01

Acetylcholinesterase and butyrylcholinesterase accumulate with brain β-amyloid (Aβ) plaques in Alzheimer disease (AD). The overall activity of acetylcholinesterase is found to decline in AD, whereas butyrylcholinesterase has been found to either increase or remain the same. Although some cognitively normal older adults also have Aβ plaques within the brain, cholinesterase-associated plaques are generally less abundant in such individuals. Thus, brain imaging of cholinesterase activity associated with Aβ plaques has the potential to distinguish AD from cognitively normal older adults, with or without Aβ accumulation, during life. Current Aβ imaging agents are not able to provide this distinction. To address this unmet need, synthesis and evaluation of a cholinesterase-binding ligand, phenyl 4-(123)I-iodophenylcarbamate ((123)I-PIP), is described. Phenyl 4-iodophenylcarbamate was synthesized and evaluated for binding potency toward acetylcholinesterase and butyrylcholinesterase using enzyme kinetic analysis. This compound was subsequently rapidly radiolabeled with (123)I and purified by high-performance liquid chromatography. Autoradiographic analyses were performed with (123)I-PIP using postmortem orbitofrontal cortex from cognitively normal and AD human brains. Comparisons were made with an Aβ imaging agent, 2-(4'-dimethylaminophenyl)-6-(123)I-iodo-imidazo[1,2-a]pyridine ((123)I-IMPY), in adjacent brain sections. Tissues were also stained for Aβ and cholinesterase activity to visualize Aβ plaque load for comparison with radioligand uptake. Synthesized and purified PIP exhibited binding to cholinesterases. (123)I was successfully incorporated into this ligand. (123)I-PIP autoradiography with human tissue revealed accumulation of radioactivity only in AD brain tissues in which Aβ plaques had cholinesterase activity. (123)I-IMPY accumulated in brain tissues with Aβ plaques from both AD and cognitively normal individuals. Radiolabeled ligands specific for cholinesterases have potential for use in neuroimaging AD plaques during life. The compound herein described, (123)I-PIP, can detect cholinesterases associated with Aβ plaques and can distinguish AD brain tissues from those of cognitively normal older adults with Aβ plaques. Imaging cholinesterase activity associated with Aβ plaques in the living brain may contribute to the definitive diagnosis of AD during life. © 2016 by the Society of Nuclear Medicine and Molecular Imaging, Inc.

Developing procedures for the large-scale purification of human serum butyrylcholinesterase.

PubMed

Saxena, Ashima; Luo, Chunyuan; Doctor, Bhupendra P

2008-10-01

Human serum butyrylcholinesterase (Hu BChE) is the most viable candidate for the prophylactic treatment of organophosphate poisoning. A dose of 200 mg/70 kg is predicted to protect humans against 2x LD(50) of soman. Therefore, the aim of this study was to develop procedures for the purification of gram quantities of this enzyme from outdated human plasma or Cohn Fraction IV-4. The purification of Hu BChE was accomplished by batch adsorption on procainamide-Sepharose-CL-4B affinity gel followed by ion-exchange chromatography on a DEAE-Sepharose column. For the purification of enzyme from Cohn Fraction IV-4, it was resuspended in 25 mM sodium phosphate buffer, pH 8.0, and fat was removed by decantation, prior to batch adsorption on procainamide-Sepharose gel. In both cases, the procainamide gel was thoroughly washed with 25 mM sodium phosphate buffer, pH 8.0, containing 0.05 M NaCl, and the enzyme was eluted with the same buffer containing 0.1 M procainamide. The enzyme was dialyzed and the pH was adjusted to 4.0 before loading on the DEAE column equilibrated in sodium acetate buffer, pH 4.0. The column was thoroughly washed with 25 mM sodium phosphate buffer, pH 8.0 containing 0.05 M NaCl before elution with a gradient of 0.05-0.2M NaCl in the same buffer. The purity of the enzyme following these steps ranged from 20% to 40%. The purity of the enzyme increased to >90% by chromatography on an analytical procainamide affinity column. Results show that Cohn Fraction IV-4 is a much better source than plasma for the large-scale isolation of purified Hu BChE.

Effect of Several New and Currently Available Oxime Cholinesterase Reactivators on Tabun-intoxicated Rats

PubMed Central

Karasova, Jana Zdarova; Kassa, Jiri; Jung, Young-Sik; Musilek, Kamil; Pohanka, Miroslav; Kuca, Kamil

2008-01-01

The therapeutical efficacies of eleven oxime-based acetylcholinesterase reactivators were compared in an in vivo (rat model) study of treatment of intoxication caused by tabun. In this group there were some currently available oximes (obidoxime, trimedoxime and HI-6) and the rest were newly synthesized compounds. The best reactivation efficacy for acetylcholinesterase in blood (expressed as percent of reactivation) among the currently available oximes was observed after administration of trimedoxime (16%) and of the newly synthesized K127 (22432) (25%). The reactivation of butyrylcholinesterase in plasma was also studied; the best reactivators were trimedoxime, K117 (22435), and K127 (22432), with overall reactivation efficacies of approximately 30%. Partial protection of brain ChE against tabun inhibition was observed after administration of trimedoxime (acetylcholinesterase 20%; butyrylcholinesterase 30%) and obidoxime (acetylcholinesterase 12%; butyrylcholinesterase 16%). PMID:19330072

Synthesis and acetylcholinesterase/butyrylcholinesterase inhibition activity of 4-amino-2, 3-diaryl-5, 6, 7, 8-tetrahydrofuro(and thieno)[2, 3-b]-quinolines, and 4-amino-5, 6, 7, 8, 9-pentahydro-2, 3-diphenylcyclohepta[e]furo(and thieno)-[2, 3-b]pyridines.

PubMed

Marco, José L; De Los Ríos, Cristóbal; Carreiras, María C; Baños, Josep E; Badia, Albert; Vivas, Nuria M

2002-07-01

The acetylcholinesterase (AChE) and butyrylcholinesterase (BuChE) inhibition activities of a series of 4-amino-2, 3-diaryl-5, 6, 7, 8-tetrahydrofuro[2, 3-b]quinolines (10-12)/4-amino-5, 6, 7, 8-tetrahydro-2, 3-diphenylthieno[2, 3-b]quinoline (14) and 4-amino-5, 6, 7, 8, 9-pentahydro-2, 3-diphenylcyclohepta[e]furo[2, 3-b]pyridine (13)/4-amino-5, 6, 7, 8, 9-pentahydro-2, 3-phenylcyclohepta[e]thieno[2, 3-b]pyridine (15) are described. These compounds are tacrine (THA) analogues which have been prepared either from readily available 2-amino-3-cyano-4, 5-diarylfurans (16-18) or from 2-amino-3-cyano-4, 5-diphenylthiophene (19), via Friedländer condensation with cyclohexanone or cycloheptanone. These compounds are competitive inhibitors for acetylcholinesterase, the more potent being compound (13) which is three-fold less active than tacrine. The butyrylcholinesterase inhibition activity is significant only in compounds 10 and133, which are ten-fold less active than tacrine. It is found that the products 11 and 12 strongly inhibit acetylcholinesterase, and show excellent selectivity regarding butyrylcholinesterase.

The rs662 polymorphism of paraoxonase 1 affects the difference in the inhibition of butyrylcholinesterase activity by organophosphorus pesticides in human blood.

PubMed

Nam, Dae Cheol; Ha, Yu Mi; Park, Min Kyu; Cho, Sung Kweon

2016-08-01

Organophosphorus pesticides (OPs) are a human health hazard. OPs inhibit acetylcholinesterase (AChE) at nerve endings and accumulate acetylcholine (ACh) at these sites. High levels of ACh and long exposure promote cholinergic crisis. The hydrolysis of OPs by serum paraoxonase 1 (PON1) plays a role in cholinergic crisis in humans. Human serum PON1 can break down organophosphate before binding to ChE. We investigated the effect of PON1 polymorphisms on AChE activity after OP treatment. 50 healthy volunteers were randomly recruited with informed consent. We investigated butyrylcholinesterase (BuChE) activity changes in plasma as a biomarker of AChE after OP treatment in human blood samples immediately following blood sampling. After the standardization of BuChE activity in human blood, we correlated changes in BuChE activity with changes in blood pH. We analyzed the PON1 polymorphisms (rs854560 and rs662) of 50 participants to retrospectively investigate the interindividual variability of changes in BuChE activity. Changes in BuChE activity are strongly correlated with pH changes after OP treatment (R2 = 0.913). We used changes in pH as a surrogate marker for BuChE inhibition after OP treatment. OP treatment significantly decreased BuChE activity by 56.4 ± 5.1% (p < 0.001). The degree of BuChE inhibition was significantly different in the PON1 rs662 genotype (56.10 ± 4.74% vs. 57.96 ± 5.67% vs. 52.34 ± 1.51%; GG vs. GA vs. AA, respectively). Changes in pH can be used as a surrogate marker for the detection of BuChE inhibition after OP exposure. The rs662 polymorphism of PON1 may explain the inter-individual variability in BuChE inhibition.

[Ligands of cholinesterases of ephedrine and pseudoephedrine structure].

PubMed

Basova, N E; Kormilitsin, B N; Perchenok, A Yu; Rozengatt, E V; Saakov, V S; Suvorov, A A

2013-01-01

The paper is a review of literature data on interaction of the mammalian erythrocyte acetylcholinesterase and blood serum butyrylcholinesterase with a group of isomer complex ester derivatives (acetates, propionates, butyrates, valerates, and isobutyrates) of bases and iodomethylates of ephedrine and its enantiomer pseudoephedrine. For 20 alkaloid monoesters, parameters of enzymatic hydrolysis are determined and their certain specificity toward acetylcholinesterase is revealed, whereas 5 diesters of iodomethylates of pseudoephedrine were hydrolyzed only by butyrylcholinesterase. The studied 20 aklaloid diesters and 10 trimethylammonium derivatives turned out to be non-competitive reversible inhibitors of acetylcholinesterase and competitive inhibitors of butyrylcholinesterase. The performed for the first time isomer and enantiomer analysis "structure-efficiency" has shown that in most cases it is possible to state the greater comlementarity of the catalytical surface of enzymes for ligands of the pseudoephedrine structure, such differentiation being realized more often at the reversible inhibition of enzymes. pseudoephedrine.

Evaluation of the inhibitory effect of abamectin on mammalian butyrylcholinesterase: Enzyme kinetic and molecular docking studies.

PubMed

Teralı, Kerem; Dalmizrak, Ozlem; Hoti, Qendresa; Ozer, Nazmi

2018-06-08

Abamectin, a blend of the natural avermectins B 1a and B 1b , is a widely-used insecticide/miticide with relatively low toxicity to mammals. Exposure to high doses of it, however, leads to cholinergic-like neurotoxic effects. Butyrylcholinesterase, which is best known for its abundant presence in plasma, is a serine hydrolase loosely coupled with the cholinergic system. It protects and supports the neurotransmitter function of its sister enzyme acetylcholinesterase. Here, using experimental and computational studies, we provide evidence demonstrating that abamectin is a potent (IC 50 = 10.6 μM; K i = 2.26 ± 0.35 μM) inhibitor of horse serum butyrylcholinesterase and that it interacts with the enzyme in a reversible, competitive manner predictively to block the mouth of the active-site gorge of the enzyme and to bind to several critical residues that normally bind/hydrolyze choline esters.

Detection of cresyl phosphate-modified butyrylcholinesterase in human plasma for chemical exposure associated with aerotoxic syndrome

PubMed Central

Schopfer, Lawrence M.; Masson, Patrick; Lamourette, Patricia; Simon, Stéphanie; Lockridge, Oksana

2014-01-01

Aircrew complain of illness following a fume event in aircraft. A chemical in jet engine oil, the neurotoxicant, tri-o-cresyl phosphate, after metabolic activation to cresyl saligenin phosphate, makes a covalent adduct on butyrylcholinesterase (BChE). We developed a mass spectrometry method for detection of the cresyl phosphate adduct on human BChE, as an indicator of exposure. Monoclonal mAb2, whose amino acid sequence is provided, was crosslinked to cyanogen bromide-activated Sepharose 4B and used to immunopurify plasma BChE treated with cresyl saligenin phosphate. BChE was released with acetic acid, digested with pepsin, and analyzed by LC-MSMS on the 5600 Triple TOF mass spectrometer. Peptide FGES198AGAAS with an added mass of 170 Da from cresyl phosphate on serine 198 was detected as parent ion 966.4 Da. When characteristic daughter ions were monitored in the MSMS spectrum the limit of detection was 0.1% cresyl saligenin phosphate inhibited plasma BChE. This corresponds to 2×10−9 g in 0.5 ml, or 23×10−15 moles of inhibited BChE in 0.5 ml plasma. In conclusion, a sensitive assay for exposure to tri-o-cresyl phosphate was developed. Laboratories that plan to use this method are cautioned that a positive result gives no proof that tri-o-cresyl phosphate is toxic at low levels. PMID:24892986

Detection of cresyl phosphate-modified butyrylcholinesterase in human plasma for chemical exposure associated with aerotoxic syndrome.

PubMed

Schopfer, Lawrence M; Masson, Patrick; Lamourette, Patricia; Simon, Stéphanie; Lockridge, Oksana

2014-09-15

Flight crews complain of illness following a fume event in aircraft. A chemical in jet engine oil, the neurotoxicant tri-o-cresyl phosphate, after metabolic activation to cresyl saligenin phosphate makes a covalent adduct on butyrylcholinesterase (BChE). We developed a mass spectrometry method for detection of the cresyl phosphate adduct on human BChE as an indicator of exposure. Monoclonal mAb2, whose amino acid sequence is provided, was crosslinked to cyanogen bromide-activated Sepharose 4B and used to immunopurify plasma BChE treated with cresyl saligenin phosphate. BChE was released with acetic acid, digested with pepsin, and analyzed by liquid chromatography-tandem mass spectrometry (LC-MSMS) on the Triple TOF 5600 mass spectrometer. Peptide FGES198AGAAS with an added mass of 170 Da from cresyl phosphate on serine 198 (Ser198) was detected as parent ion 966.4 Da. When characteristic daughter ions were monitored in the MSMS spectrum, the limit of detection was 0.1% cresyl saligenin phosphate inhibited plasma BChE. This corresponds to 2×10(-9) g in 0.5 ml or 23×10(-15) moles of inhibited BChE in 0.5 ml of plasma. In conclusion, a sensitive assay for exposure to tri-o-cresyl phosphate was developed. Laboratories that plan to use this method are cautioned that a positive result gives no proof that tri-o-cresyl phosphate is toxic at low levels. Copyright © 2014 Elsevier Inc. All rights reserved.

INHIBITION OF HUMAN ACETYL- AND BUTYRYLCHOLINESTERASE BY NOVEL CARBAMATES OF (−)- AND (+)-TETRAHYDROFUROBENZOFURAN AND METHANOBENZODIOXEPINE

PubMed Central

Luo, Weiming; Yu, Qian-sheng; Kulkarni, Santosh S.; Parrish, Damon A.; Holloway, Harold W.; Tweedie, David; Shafferman, Avigdor; Lahiri, Debomoy K.; Brossi, Arnold; Greig, Nigel H.

2008-01-01

A new enantiomeric synthesis utilizing classical resolution provided two novel series of optically active inhibitors of cholinesterase: (−)- and (+)- O-carbamoyl phenols of tetrahydrofurobenzofuran and methanobenzodioxepine. An additional two series of (−)- and (+)-O-carbamoyl phenols of pyrroloindole and furoindole were obtained by known procedures, and their anticholinesterase actions were similarly quantified against freshly prepared human acetyl- (AChE) and butyrylcholinesterase (BChE). Both enantiomeric forms of each series demonstrated potent cholinesterase inhibitory activity (with IC50 values as low as 10 nM for AChE and 3 nM for BChE), with the exception of the (+)-O-carbamoyl phenols of pyrroloindole that lacked activity (IC50 values > 1 µM). Based on the biological data of these four series, a SAR analysis was provided by molecular volume calculations. In addition, a probable transition state model was established according to the known X-ray structure of a transition state complex of Torpedo californica AChE-m-(N,N,N,trimethylammonio)-2,2,2-trifluoroacetophenone (TcAChE-TMTFA). This model proved valuable in explaining the enantio-selectivity and enzyme subtype selectivity of each series. These carbamates are more or similarly potent to anticholinesterases in current clinical use; providing not only inhibitors of potential clinical relevance but also pharmacological tools to define drug-enzyme binding interactions within an enzyme crucial in the maintenance of cognition and numerous systemic physiological functions in health, aging and disease. PMID:16570913

Quantitation of ortho-cresyl phosphate adducts to butyrylcholinesterase in human serum by immunomagnetic-UHPLC-MS/MS.

PubMed

Johnson, Darryl; Carter, Melissa D; Crow, Brian S; Isenberg, Samantha L; Graham, Leigh Ann; Erol, H Akin; Watson, Caroline M; Pantazides, Brooke G; van der Schans, Marcel J; Langenberg, Jan P; Noort, Daan; Blake, Thomas A; Thomas, Jerry D; Johnson, Rudolph C

2015-04-01

Tri-ortho-cresyl phosphate (ToCP) is an anti-wear, flame retardant additive used in industrial lubricants, hydraulic fluids and gasoline. The neurotoxic effects of ToCP arise from the liver-activated metabolite 2-(o-cresyl)-4H-1,3,2-benzodioxaphosphoran-2-one (cresyl saligenin phosphate or CBDP), which inhibits esterase enzymes including butyrylcholinesterase (BChE). Following BChE adduction, CBDP undergoes hydrolysis to form the aged adduct ortho-cresyl phosphoserine (oCP-BChE), thus providing a biomarker of CBDP exposure. Previous studies have identified ToCP in aircraft cabin and cockpit air, but assessing human exposure has been hampered by the lack of a laboratory assay to confirm exposure. This work presents the development of an immunomagnetic-UHPLC-MS/MS method for the quantitation of unadducted BChE and the long-term CBDP biomarker, oCP-BChE, in human serum. The method has a reportable range from 2.0 ng/ml to 150 ng/ml, which is consistent with the sensitivity of methods used to detect organophosphorus nerve agent protein adducts. The assay demonstrated high intraday and interday accuracy (≥85%) and precision (RSD ≤ 15%) across the calibration range. The method was developed for future analyses of potential human exposure to CBDP. Analysis of human serum inhibited in vitro with CBDP demonstrated that the oCP-BChE adduct was stable for at least 72 h at 4, 22 and 37 °C. Compared to a previously reported assay, this method requires 75% less sample volume, reduces analysis time by a factor of 20 and demonstrates a threefold improvement in sensitivity. Published 2015. This article is a U.S. Government work and is in the public domain in the USA. Published 2015. This article is a U.S. Government work and is in the public domain in the USA.

Hupresin Retains Binding Capacity for Butyrylcholinesterase and Acetylcholinesterase after Sanitation with Sodium Hydroxide.

PubMed

Onder, Seda; David, Emilie; Tacal, Ozden; Schopfer, Lawrence M; Lockridge, Oksana

2017-01-01

Hupresin is a new affinity resin that binds butyrylcholinesterase (BChE) in human plasma and acetylcholinesterase (AChE) solubilized from red blood cells (RBC). Hupresin is available from the CHEMFORASE company. BChE in human plasma binds to Hupresin and is released with 0.1 M trimethylammonium bromide (TMA) with full activity and 10-15% purity. BChE immunopurified from plasma by binding to immobilized monoclonal beads has fewer contaminating proteins than the one-step Hupresin-purified BChE. However, when affinity chromatography on Hupresin follows ion exchange chromatography at pH 4.5, BChE is 99% pure. The membrane bound AChE, solubilized from human RBC with 0.6% Triton X-100, binds to Hupresin and remains bound during washing with sodium chloride. Human AChE is not released in significant quantities with non-denaturing solvents, but is recovered in 1% trifluoroacetic acid. The denatured, partially purified AChE is useful for detecting exposure to nerve agents by mass spectrometry. Our goal was to determine whether Hupresin retains binding capacity for BChE and AChE after Hupresin is washed with 0.1 M NaOH. A 2 mL column of Hupresin equilibrated in 20 mM TrisCl pH 7.5 was used in seven consecutive trials to measure binding and recovery of BChE from 100 mL human plasma. Between each trial the Hupresin was washed with 10 column volumes of 0.1 M sodium hydroxide. A similar trial was conducted with red blood cell AChE in 0.6% Triton X-100. It was found that the binding capacity for BChE and AChE was unaffected by washing Hupresin with 0.1 M sodium hydroxide. Hupresin could be washed with sodium hydroxide at least seven times without losing binding capacity.

DOE Office of Scientific and Technical Information (OSTI.GOV)

Liyasova, Mariya, E-mail: mliyasov@unmc.edu; Department of Environmental, Agricultural, and Occupational Health, University of Nebraska Medical Center, Omaha, NE; Li, Bin, E-mail: binli@unmc.edu

The aircraft cabin and flight deck ventilation are supplied from partially compressed unfiltered bleed air directly from the engine. Worn or defective engine seals can result in the release of engine oil into the cabin air supply. Aircrew and passengers have complained of illness following such 'fume events'. Adverse health effects are hypothesized to result from exposure to tricresyl phosphate mixed esters, a chemical added to jet engine oil and hydraulic fluid for its anti-wear properties. Our goal was to develop a laboratory test for exposure to tricresyl phosphate. The assay was based on the fact that the active-site serinemore » of butyrylcholinesterase reacts with the active metabolite of tri-o-cresyl phosphate, cresyl saligenin phosphate, to make a stable phosphorylated adduct with an added mass of 80 Da. No other organophosphorus agent makes this adduct in vivo on butyrylcholinesterase. Blood samples from jet airplane passengers were obtained 24-48 h after completing a flight. Butyrylcholinesterase was partially purified from 25 ml serum or plasma, digested with pepsin, enriched for phosphorylated peptides by binding to titanium oxide, and analyzed by mass spectrometry. Of 12 jet airplane passengers tested, 6 were positive for exposure to tri-o-cresyl phosphate that is, they had detectable amounts of the phosphorylated peptide FGEpSAGAAS. The level of exposure was very low. No more than 0.05 to 3% of plasma butyrylcholinesterase was modified. None of the subjects had toxic symptoms. Four of the positive subjects were retested 3 to 7 months following their last airplane trip and were found to be negative for phosphorylated butyrylcholinesterase. In conclusion, this is the first report of an assay that detects exposure to tri-o-cresyl phosphate in jet airplane travelers. -- Highlights: Black-Right-Pointing-Pointer Travel on jet airplanes is associated with an illness, aerotoxic syndrome. Black-Right-Pointing-Pointer A possible cause is exposure to tricresyl phosphate in engine lubricating oil. Black-Right-Pointing-Pointer A blood test for exposure to tri-o-cresyl phosphate is reported.« less

Naturally Occurring Genetic Variants of Human Acetylcholinesterase and Butyrylcholinesterase and Their Potential Impact on the Risk of Toxicity from Cholinesterase Inhibitors

PubMed Central

2016-01-01

Acetylcholinesterase (AChE) is the physiologically important target for organophosphorus toxicants (OP) including nerve agents and pesticides. Butyrylcholinesterase (BChE) in blood serves as a bioscavenger that protects AChE in nerve synapses from inhibition by OP. Mass spectrometry methods can detect exposure to OP by measuring adducts on the active site serine of plasma BChE. Genetic variants of human AChE and BChE do exist, but loss of function mutations have been identified only in the BCHE gene. The most common AChE variant, His353Asn (H322N), also known as the Yt blood group antigen, has normal AChE activity. The most common BChE variant, Ala567Thr (A539T) or the K-variant in honor of Werner Kalow, has 33% reduced plasma BChE activity. The genetic variant most frequently associated with prolonged response to muscle relaxants, Asp98Gly (D70G) or atypical BChE, has reduced activity and reduced enzyme concentration. Early studies in young, healthy males, performed at a time when it was legal to test nerve agents in humans, showed that individuals responded differently to the same low dose of sarin with toxic symptoms ranging in severity from minimal to moderate. Additionally, animal studies indicated that BChE protects from toxicants that have a higher reactivity with AChE than with BChE (e.g., nerve agents) but not from toxicants that have a higher reactivity with BChE than with AChE (e.g., OP pesticides). As a corollary, we hypothesize that individuals with genetic variants of BChE may be at increased risk of toxicity from nerve agents but not from OP pesticides. PMID:27551784

Naturally Occurring Genetic Variants of Human Acetylcholinesterase and Butyrylcholinesterase and Their Potential Impact on the Risk of Toxicity from Cholinesterase Inhibitors.

PubMed

Lockridge, Oksana; Norgren, Robert B; Johnson, Rudolph C; Blake, Thomas A

2016-09-19

Acetylcholinesterase (AChE) is the physiologically important target for organophosphorus toxicants (OP) including nerve agents and pesticides. Butyrylcholinesterase (BChE) in blood serves as a bioscavenger that protects AChE in nerve synapses from inhibition by OP. Mass spectrometry methods can detect exposure to OP by measuring adducts on the active site serine of plasma BChE. Genetic variants of human AChE and BChE do exist, but loss of function mutations have been identified only in the BCHE gene. The most common AChE variant, His353Asn (H322N), also known as the Yt blood group antigen, has normal AChE activity. The most common BChE variant, Ala567Thr (A539T) or the K-variant in honor of Werner Kalow, has 33% reduced plasma BChE activity. The genetic variant most frequently associated with prolonged response to muscle relaxants, Asp98Gly (D70G) or atypical BChE, has reduced activity and reduced enzyme concentration. Early studies in young, healthy males, performed at a time when it was legal to test nerve agents in humans, showed that individuals responded differently to the same low dose of sarin with toxic symptoms ranging in severity from minimal to moderate. Additionally, animal studies indicated that BChE protects from toxicants that have a higher reactivity with AChE than with BChE (e.g., nerve agents) but not from toxicants that have a higher reactivity with BChE than with AChE (e.g., OP pesticides). As a corollary, we hypothesize that individuals with genetic variants of BChE may be at increased risk of toxicity from nerve agents but not from OP pesticides.

Report: screening of selected medicinal plants for their enzyme inhibitory potential - a validation of their ethnopharmacological uses.

PubMed

Khuda, Fazli; Iqbal, Zafar; Khan, Ayub; Zakiullah; Shah, Yasar; Khan, Abad

2014-05-01

In present study four medicinal plants namely Valeriana wallichii, Xanthium strumarium, Achyranthes aspera and Duchesnea indica belonging to different families were collected in Khyber Pakhtunkhwa province and crude extract and subsequent fractions were analyzed for their inhibitory potential against acetylcholinesterase, butyrylcholinesterase and α-glucosidase enzymes. Valeriana wallichii, Xanthium strumarium and Achyranthes aspera were significantly active against cholinesterases. Chloroform and ethylacetate fractions of Valeriana wallichii exhibited significant activity against acetylcholinesterase (IC50: 61μg/ml) and butyrylcholinesterase enzymes (IC50: 58μg/ml), respectively. Similarly ethylacetate fraction of Achyranthes aspera showed significant activity against acetylcholinesterase (IC50: 61 μg/ml) and butyrylcholinesterase enzymes (IC50: 61 μg/ml), respectively. In case of α-glucosidase enzyme, the chloroform fraction of Xanthium strumarium exhibited significant inhibitory activity (IC50: 72 μg/ml) as compared to the standard compound acarbose (IC50: 483 μg/ml). Duchesnea indica showed no such activities.

Novel N-allyl/propargyl tetrahydroquinolines: Synthesis via Three-component Cationic Imino Diels-Alder Reaction, Binding Prediction, and Evaluation as Cholinesterase Inhibitors.

PubMed

Rodríguez, Yeray A; Gutiérrez, Margarita; Ramírez, David; Alzate-Morales, Jans; Bernal, Cristian C; Güiza, Fausto M; Romero Bohórquez, Arnold R

2016-10-01

New N-allyl/propargyl 4-substituted 1,2,3,4-tetrahydroquinolines derivatives were efficiently synthesized using acid-catalyzed three components cationic imino Diels-Alder reaction (70-95%). All compounds were tested in vitro as dual acetylcholinesterase and butyryl-cholinesterase inhibitors and their potential binding modes, and affinity, were predicted by molecular docking and binding free energy calculations (∆G) respectively. The compound 4af (IC50 = 72 μm) presented the most effective inhibition against acetylcholinesterase despite its poor selectivity (SI = 2), while the best inhibitory activity on butyryl-cholinesterase was exhibited by compound 4ae (IC50 = 25.58 μm) with considerable selectivity (SI = 0.15). Molecular docking studies indicated that the most active compounds fit in the reported acetylcholinesterase and butyryl-cholinesterase active sites. Moreover, our computational data indicated a high correlation between the calculated ∆G and the experimental activity values in both targets. © 2016 The Authors Chemical Biology & Drug Design Published by John Wiley & Sons Ltd.

Characterization of procaine metabolism as probe for the butyrylcholinesterase enzyme investigation by simultaneous determination of procaine and its metabolite using capillary electrophoresis with electrochemiluminescence detection.

PubMed

Yuan, Jipei; Yin, Jianyuan; Wang, Erkang

2007-06-22

Capillary electrophoresis with electrochemiluminescene detection was used to characterize procaine hydrolysis as a probe for butyrylcholinesterase by in vitro procaine metabolism in plasma with butyrylcholinesterase acting as bioscavenger. Procaine and its metabolite N,N-diethylethanolamine were separated at 16 kV and then detected at 1.25 V in the presence of 5.0 mM Ru(bpy)(3)2+, with the detection limits of 2.4x10(-7) and 2.0x10(-8) mol/L (S/N=3), respectively. The Michaelis constant Km value was 1.73x10(-4) mol/L and the maximum velocity Vmax was 1.62x10(-6) mol/L/min. Acetylcholine bromide and choline chloride presented inhibition effects on the enzymatic cleavage of procaine, with the 50% inhibition concentration (IC50) of 6.24x10(-3) and 2.94x10(-4) mol/L.

Development of organophosphate hydrolase activity in a bacterial homolog of human cholinesterase

NASA Astrophysics Data System (ADS)

Legler, Patricia; Boisvert, Susanne; Compton, Jaimee; Millard, Charles

2014-07-01

We applied a combination of rational design and directed evolution (DE) to Bacillus subtilis p-nitrobenzyl esterase (pNBE) with the goal of enhancing organophosphorus acid anhydride hydrolase (OPAAH) activity. DE started with a designed variant, pNBE A107H, carrying a histidine homologous with human butyrylcholinesterase G117H to find complementary mutations that further enhance its OPAAH activity. Five sites were selected (G105, G106, A107, A190, and A400) within a 6.7 Å radius of the nucleophilic serine O?. All 95 variants were screened for esterase activity with a set of five substrates: pNP-acetate, pNP-butyrate, acetylthiocholine, butyrylthiocholine, or benzoylthiocholine. A microscale assay for OPAAH activity was developed for screening DE libraries. Reductions in esterase activity were generally concomitant with enhancements in OPAAH activity. One variant, A107K, showed an unexpected 7-fold increase in its kcat/Km for benzoylthiocholine, demonstrating that it is also possible to enhance the cholinesterase activity of pNBE. Moreover, DE resulted in at least three variants with modestly enhanced OPAAH activity compared to wild type pNBE. A107H/A190C showed a 50-fold increase in paraoxonase activity and underwent a slow time- and temperature-dependent change affecting the hydrolysis of OPAA and ester substrates. Structural analysis suggests that pNBE may represent a precursor leading to human cholinesterase and carboxylesterase 1 through extension of two vestigial specificity loops; a preliminary attempt to transfer the Ω-loop of BChE into pNBE is described. pNBE was tested as a surrogate scaffold for mammalian esterases. Unlike butyrylcholinesterase and pNBE, introducing a G143H mutation (equivalent to G117H) did not confer detectable OP hydrolase activity on human carboxylesterase 1. We discuss the importance of the oxyanion-hole residues for enhancing the OPAAH activity of selected serine hydrolases.

Iminosugars as a new class of cholinesterase inhibitors.

PubMed

Decroocq, Camille; Stauffert, Fabien; Pamlard, Olivier; Oulaïdi, Farah; Gallienne, Estelle; Martin, Olivier R; Guillou, Catherine; Compain, Philippe

2015-02-15

To further extend the scope of iminosugar biological activity, a systematic structure-activity relationship investigation has been performed by synthesizing and evaluating as cholinesterase inhibitors a library of twenty-three iminoalditols with different substitutions and stereochemistry patterns. These compounds have been evaluated in vitro for the inhibition of cholinesterases (different sources of acetylcholinesterase and butyrylcholinesterase). Some compounds have IC50 values in the micromolar range and display significant inhibition selectivity for butyrylcholinesterase over acetylcholinesterase. These are the first examples of iminosugar-based inhibitors of cholinesterases. Copyright © 2015 Elsevier Ltd. All rights reserved.

Butyrylcholinesterase gene transfer in obese mice prevents postdieting body weight rebound by suppressing ghrelin signaling.

PubMed

Chen, Vicky Ping; Gao, Yang; Geng, Liyi; Brimijoin, Stephen

2017-10-10

The worldwide prevalence of obesity is increasing at an alarming rate but treatment options remain limited. Despite initial success, weight loss by calorie restriction (CR) often fails because of rebound weight gain. Postdieting hyperphagia along with altered hypothalamic neuro-architecture appears to be one direct cause of this undesirable outcome. In response to calorie deficiency the circulating levels of the appetite-promoting hormone, acyl-ghrelin, rise sharply. We hypothesize that proper modulation of acyl-ghrelin and its receptor's sensitivity will favorably impact energy intake and reprogram the body weight set point. Here we applied viral gene transfer of the acyl-ghrelin hydrolyzing enzyme, butyrylcholinesterase (BChE), in a mouse model of diet-induced obesity. Our results confirmed that BChE overexpression decreased circulating acyl-ghrelin levels, suppressed CR-provoked ghrelin signaling, and restored central ghrelin sensitivity. In addition to maintaining healthy body weights, BChE treated mice had modest postdieting food intake and showed normal glucose homeostasis. Spontaneous activity and energy expenditure did not differ significantly between treated and untreated mice after body weight rebound, suggesting that BChE gene transfer did not alter energy expenditure in the long term. These findings indicate that combining BChE treatment with CR could be an effective approach in treating human obesity and aiding lifelong weight management.

Structural Study of the Complex Stereoselectivity of Human Butyrylcholinesterase for the Neurotoxic V-agents*

PubMed Central

Wandhammer, Marielle; Carletti, Eugénie; Van der Schans, Marcel; Gillon, Emilie; Nicolet, Yvain; Masson, Patrick; Goeldner, Maurice; Noort, Daan; Nachon, Florian

2011-01-01

Nerve agents are chiral organophosphate compounds (OPs) that exert their acute toxicity by phosphorylating the catalytic serine of acetylcholinesterase (AChE). The inhibited cholinesterases can be reactivated using oximes, but a spontaneous time-dependent process called aging alters the adduct, leading to resistance toward oxime reactivation. Human butyrylcholinesterase (BChE) functions as a bioscavenger, protecting the cholinergic system against OPs. The stereoselectivity of BChE is an important parameter for its efficiency at scavenging the most toxic OPs enantiomer for AChE. Crystals of BChE inhibited in solution or in cristallo with racemic V-agents (VX, Russian VX, and Chinese VX) systematically show the formation of the PS adduct. In this configuration, no catalysis of aging seems possible as confirmed by the three-dimensional structures of the three conjugates incubated over a period exceeding a week. Crystals of BChE soaked in optically pure VXR-(+) and VXS-(−) solutions lead to the formation of the PS and PR adduct, respectively. These structural data support an in-line phosphonylation mechanism. Additionally, they show that BChE reacts with VXR-(+) in the presence of racemic mixture of V-agents, at odds with earlier kinetic results showing a moderate higher inhibition rate for VXS-(−). These combined results suggest that the simultaneous presence of both enantiomers alters the enzyme stereoselectivity. In summary, the three-dimensional data show that BChE reacts preferentially with PR enantiomer of V-agents and does not age, in complete contrast to AChE, which is selectively inhibited by the PS enantiomer and ages. PMID:21454498

A direct method to visualise the aryl acylamidase activity on cholinesterases in polyacrylamide gels

PubMed Central

Jaganathan, Lakshmanan; Boopathy, Rathanam

2000-01-01

Background In vertebrates, two types of cholinesterases exist, acetylcholinesterase and butyrylcholinesterase. The function of acetylcholinesterase is to hydrolyse acetylcholine, thereby terminating the neurotransmission at cholinergic synapse, while the precise physiological function of butyrylcholinesterase has not been identified. The presence of cholinesterases in tissues that are not cholinergically innervated indicate that cholinesterases may have functions unrelated to neurotransmission. Furthermore, cholinesterases display a genuine aryl acylamidase activity apart from their predominant acylcholine hydrolase activity. The physiological significance of this aryl acylamidase activity is also not known. The study on the aryl acylamidase has been, in part hampered by the lack of a specific method to visualise this activity. We have developed a method to visualise the aryl acylamidase activity on cholinesterase in polyacrylamide gels. Results The o-nitroaniline liberated from o-nitroacetanilide by the action of aryl acylamidase activity on cholinesterases, in the presence of nitrous acid formed a diazonium compound. This compound gave an azo dye complex with N-(1-napthyl)-ethylenediamine, which appeared as purple bands in polyacrylamide gels. Treating the stained gels with trichloroacetic acid followed by Tris-HCl buffer helped in fixation of the stain in the gels. By using specific inhibitors for acetylcholinesterase and butyrylcholinesterase, respectively, differential staining for the aryl acylamidase activities on butyrylcholinesterase and acetylcholinesterase in a sample containing both these enzymes has been demonstrated. A linear relationship between the intensity of colour developed and activity of the enzyme was obtained. Conclusions A novel method to visualise the aryl acylamidase activity on cholinesterases in polyacrylamide gels has been developed. PMID:11231883

A direct method to visualise the aryl acylamidase activity on cholinesterases in polyacrylamide gels.

PubMed

Jaganathan, L; Boopathy, R

2000-01-01

In vertebrates, two types of cholinesterases exist, acetylcholinesterase and butyrylcholinesterase. The function of acetylcholinesterase is to hydrolyse acetylcholine, thereby terminating the neurotransmission at cholinergic synapse, while the precise physiological function of butyrylcholinesterase has not been identified. The presence of cholinesterases in tissues that are not cholinergically innervated indicate that cholinesterases may have functions unrelated to neurotransmission. Furthermore, cholinesterases display a genuine aryl acylamidase activity apart from their predominant acylcholine hydrolase activity. The physiological significance of this aryl acylamidase activity is also not known. The study on the aryl acylamidase has been, in part hampered by the lack of a specific method to visualise this activity. We have developed a method to visualise the aryl acylamidase activity on cholinesterase in polyacrylamide gels. The o-nitroaniline liberated from o-nitroacetanilide by the action of aryl acylamidase activity on cholinesterases, in the presence of nitrous acid formed a diazonium compound. This compound gave an azo dye complex with N-(1-napthyl)-ethylenediamine, which appeared as purple bands in polyacrylamide gels. Treating the stained gels with trichloroacetic acid followed by Tris-HCl buffer helped in fixation of the stain in the gels. By using specific inhibitors for acetylcholinesterase and butyrylcholinesterase, respectively, differential staining for the aryl acylamidase activities on butyrylcholinesterase and acetylcholinesterase in a sample containing both these enzymes has been demonstrated. A linear relationship between the intensity of colour developed and activity of the enzyme was obtained. A novel method to visualise the aryl acylamidase activity on cholinesterases in polyacrylamide gels has been developed.

Evaluation of nitrate-substituted pseudocholine esters of aspirin as potential nitro-aspirins.

PubMed

Gilmer, John F; Moriarty, Louise M; Clancy, John M

2007-06-01

Herein we explore some designs for nitro-aspirins, compounds potentially capable of releasing both aspirin and nitric oxide in vivo. A series of nitrate-bearing alkyl esters of aspirin were prepared based on the choline ester template preferred by human plasma butyrylcholinesterase. The degradation kinetics of the compounds were followed in human plasma solution. All compounds underwent hydrolysis rapidly (t(1/2) approximately 1min) but generating exclusively the corresponding nitro-salicylate. The one exception, an N-propyl, N-nitroxyethyl aminoethanol ester produced 9.2% aspirin in molar terms indicating that the nitro-aspirin objective is probably achievable if due cognisance can be paid to the demands of the activating enzyme. Even at this low level of aspirin release, this compound is the most successful nitro-aspirin reported to date in the key human plasma model.

Butyrylcholinesterase, lipoxygenase inhibiting and antifungal alkaloids from Isatis tinctoria.

PubMed

Ahmad, Ijaz; Fatima, Itrat

2008-06-01

Phytochemical investigations on the alkaloidal fraction of the whole plant of the Isatis tinctoria led to the isolation of the alkaloids 1-6. Compounds 3, 2 were found to be potent butyrylcholinesterase and lipoxygenase enzymes inhibitors in a concentration-dependent manner with the IC(50) values 16.3 +/- 0.06 and 19.7 +/- 0.03 microM against BChE and 30.6 +/- 0.02 and 33.7 +/- 0.05 microM against LOX, respectively. The compounds (1-6) showed significant antifungal activity against Trichophyton schoen leinii, Aspergillus niger, Candida albicans, Trichophyton simii, and Macrophomina phaseolina.

Interception of Cocaine by Enzyme or Antibody Delivered with Viral Gene Transfer: A Novel Strategy for Preventing Relapse in Recovering Drug Users

PubMed Central

Brimijoin, Stephen

2013-01-01

Recent progress in enzyme engineering has led to versions of human butyrylcholinesterase (BChE) that hydrolyze cocaine efficiently in plasma, reduce concentrations reaching reward neurocircuity in the brain, and weaken behavioral responses to this drug. Along with enzyme advances, increasingly avid anti-cocaine antibodies and potent anti-cocaine vaccines have also been developed. Here we review these developments and consider the potential advantages along with the risks of delivering drug-intercepting proteins via gene transfer approaches to treat cocaine addiction. PMID:22229308

Effects of viscosity and osmotic stress on the reaction of human butyrylcholinesterase with cresyl saligenin phosphate, a toxicant related to aerotoxic syndrome: kinetic and molecular dynamics studies.

PubMed

Masson, Patrick; Lushchekina, Sofya; Schopfer, Lawrence M; Lockridge, Oksana

2013-09-15

CSP (cresyl saligenin phosphate) is an irreversible inhibitor of human BChE (butyrylcholinesterase) that has been involved in the aerotoxic syndrome. Inhibition under pseudo-first-order conditions is biphasic, reflecting a slow equilibrium between two enzyme states E and E'. The elementary constants for CSP inhibition of wild-type BChE and D70G mutant were determined by studying the dependence of inhibition kinetics on viscosity and osmotic pressure. Glycerol and sucrose were used as viscosogens. Phosphorylation by CSP is sensitive to viscosity and is thus strongly diffusion-controlled (kon≈10⁸ M⁻¹·min⁻¹). Bimolecular rate constants (ki) are about equal to kon values, making CSP one of the fastest inhibitors of BChE. Sucrose caused osmotic stress because it is excluded from the active-site gorge. This depleted the active-site gorge of water. Osmotic activation volumes, determined from the dependence of ki on osmotic pressure, showed that water in the gorge of the D70G mutant is more easily depleted than that in wild-type BChE. This demonstrates the importance of the peripheral site residue Asp⁷⁰ in controlling the active-site gorge hydration. MD simulations provided new evidence for differences in the motion of water within the gorge of wild-type and D70G enzymes. The effect of viscosogens/osmolytes provided information on the slow equilibrium E⇌E', indicating that alteration in hydration of a key catalytic residue shifts the equilibrium towards E'. MD simulations showed that glycerol molecules that substitute for water molecules in the enzyme active-site gorge induce a conformational change in the catalytic triad residue His⁴³⁸, leading to the less reactive form E'.

Modeling evolution of hydrogen bonding and stabilization of transition states in the process of cocaine hydrolysis catalyzed by human butyrylcholinesterase.

PubMed

Gao, Daquan; Zhan, Chang-Guo

2006-01-01

Molecular dynamics (MD) simulations and quantum mechanical/molecular mechanical (QM/MM) calculations were performed on the prereactive enzyme-substrate complex, transition states, intermediates, and product involved in the process of human butyrylcholinesterase (BChE)-catalyzed hydrolysis of (-)-cocaine. The computational results consistently reveal a unique role of the oxyanion hole (consisting of G116, G117, and A199) in BChE-catalyzed hydrolysis of cocaine, compared to acetylcholinesterase (AChE)-catalyzed hydrolysis of acetylcholine. During BChE-catalyzed hydrolysis of cocaine, only G117 has a hydrogen bond with the carbonyl oxygen (O31) of the cocaine benzoyl ester in the prereactive BChE-cocaine complex, and the NH groups of G117 and A199 are hydrogen-bonded with O31 of cocaine in all of the transition states and intermediates. Surprisingly, the NH hydrogen of G116 forms an unexpected hydrogen bond with the carboxyl group of E197 side chain and, therefore, is not available to form a hydrogen bond with O31 of cocaine in the acylation. The NH hydrogen of G116 is only partially available to form a weak hydrogen bond with O31 of cocaine in some structures involved in the deacylation. The change of the estimated hydrogen-bonding energy between the oxyanion hole and O31 of cocaine during the reaction process demonstrates how the protein environment can affect the energy barrier for each step of the BChE-catalyzed hydrolysis of cocaine. These insights concerning the effects of the oxyanion hole on the energy barriers provide valuable clues on how to rationally design BChE mutants with a higher catalytic activity for the hydrolysis of (-)-cocaine. 2005 Wiley-Liss, Inc.

Modeling Evolution of Hydrogen Bonding and Stabilization of Transition States in the Process of Cocaine Hydrolysis Catalyzed by Human Butyrylcholinesterase

PubMed Central

Gao, Daquan; Zhan, Chang-Guo

2010-01-01

Molecular dynamics (MD) simulations and quantum mechanical/molecular mechanical (QM/MM) calculations were performed on the prereactive enzyme-substrate complex, transition states, intermediates, and product involved in the process of human butyrylcholinesterase (BChE)-catalyzed hydrolysis of (−)-cocaine. The computational results consistently reveal a unique role of the oxyanion hole (consisting of G116, G117, and A199) in BChE-catalyzed hydrolysis of cocaine, as compared to acetylcholinesterase (AChE)-catalyzed hydrolysis of acetylcholine. During BChE-catalyzed hydrolysis of cocaine, only G117 has a hydrogen bond with the carbonyl oxygen (O31) of the cocaine benzoyl ester in the prereactive BChE-cocaine complex, and the NH groups of G117 and A199 are hydrogen-bonded with O31 of cocaine in all of the transition states and intermediates. Surprisingly, the NH hydrogen of G116 forms an unexpected hydrogen bond with the carboxyl group of E197 side chain and, therefore, is not available to form a hydrogen bond with O31 of cocaine in the acylation. The NH hydrogen of G116 is only partially available to form a weak hydrogen bond with O31 of cocaine in some structures involved in the deacylation. The change of the estimated hydrogen bonding energy between the oxyanion hole and O31 of cocaine during the reaction process demonstrates how the protein environment can affect the energy barrier for each step of the BChE-catalyzed hydrolysis of cocaine. These insights concerning the effects of the oxyanion hole on the energy barriers provide valuable clues on how to rationally design BChE mutants with a higher catalytic activity for the hydrolysis of (−)-cocaine. PMID:16288482

Antioxidant, anticancer and anticholinesterase activities of flower, fruit and seed extracts of Hypericum amblysepalum HOCHST.

PubMed

Keskin, Cumali

2015-01-01

Cancer is an unnatural type of tissue growth in which the cells exhibit unrestrained division, leading to a progressive increase in the number of dividing cells. It is now the second largest cause of death in the world. The present study concerned antioxidant, anticancer and anticholinesterase activities and protocatechuic, catechin, caffeic acid, syringic acid, p-coumaric acid and o-coumaric concentrations in methanol extracts of flowers, fruits and seeds of Hypericum amblysepalum. Antioxidant properties including free radical scavenging activity and reducing power, and amounts of total phenolic compounds were evaluated using different tests. Protocatechuic, catechin, caffeic acid, syringic acid, p-coumaric acid and o-coumaric concentrations in extracts were determined by HPLC. Cytotoxic effects were determined using the MTT test with human cervix cancer (HeLa) and rat kidney epithelium cell (NRK-52E) lines. Acetyl and butyrylcholinesterase inhibitory activities were measured by by Ellman method. Total phenolic content of H. amblysepalum seeds was found to be higher than in fruit and flower extracts. DPPH free radical scavenging activity of the obtained extracts gave satisfactory results versus butylated hydroxyanisole and butylated hydroxytoluene as controls. Reducing power activity was linearly proportional to the studied concentration range: 10-500 μg/ mL LC50 values for H. amblysepalum seeds were 11.7 and 2.86 respectively for HeLa and NRK-52E cell lines. Butyryl-cholinesterase inhibitory activity was 76.9±0.41 for seed extract and higher than with other extracts. The present results suggested that H. amblysepalum could be a potential candidate anti-cancer drug for the treatment of human cervical cancer, and good source of natural antioxidants.

Pretreatment with human serum butyrylcholinesterase alone prevents cardiac abnormalities, seizures, and death in Göttingen minipigs exposed to sarin vapor.

PubMed

Saxena, Ashima; Sun, Wei; Dabisch, Paul A; Hulet, Stanley W; Hastings, Nicholas B; Jakubowski, Edward M; Mioduszewski, Robert J; Doctor, Bhupendra P

2011-12-15

Human serum butyrylcholinesterase (Hu BChE) is a stoichiometric bioscavenger that is being developed as a prophylactic countermeasure against organophosphorus nerve agents. This study was designed to evaluate the efficacy of Hu BChE against whole-body inhalation exposure to a lethal dose of sarin (GB) vapor. Male Göttingen minipigs were subjected to: air exposure, GB vapor exposure, or pretreatment with Hu BChE followed by GB vapor exposure. Hu BChE was administered by i.m. injection 24 h prior to exposure to 4.1 mg/m(3) of GB vapor for 60 min. Electrocardiograms (ECG), electroencephalograms (EEG), and pupil size were recorded throughout exposure. Blood drawn before and throughout exposure was analyzed for blood gases, electrolytes, metabolites, acetylcholinesterase and BChE activities, and amount of GB present. Untreated animals exposed to GB vapor exhibited cardiac abnormalities and generalized seizures, ultimately succumbing to respiratory failure. Pretreatment with 3.0 or 6.5 mg/kg of Hu BChE delayed blood gas and acid-base disturbances and the onset of cardiac and neural toxic signs, but failed to increase survivability. Pretreatment with 7.5 mg/kg of Hu BChE, however, completely prevented toxic signs, with blood chemistry and ECG and EEG parameters indistinguishable from control during and after GB exposure. GB bound in plasma was 200-fold higher than plasma from pigs that did not receive Hu BChE, suggesting that Hu BChE scavenged GB in blood and prevented it from reaching other tissues. Thus, prophylaxis with Hu BChE alone not only increased survivability, but also prevented cardiac abnormalities and neural toxicity in minipigs exposed to a lethal dose of GB vapor. Published by Elsevier Inc.

Prophylaxis with human serum butyrylcholinesterase protects Göttingen minipigs exposed to a lethal high-dose of sarin vapor.

PubMed

Saxena, Ashima; Hastings, Nicholas B; Sun, Wei; Dabisch, Paul A; Hulet, Stanley W; Jakubowski, Edward M; Mioduszewski, Robert J; Doctor, Bhupendra P

2015-08-05

Serum-derived human butyrylcholinesterase (Hu BChE) is a stoichiometric bioscavenger that is being developed as a potential prophylactic nerve agent countermeasure. Previously, we reported the prophylactic efficacy of Hu BChE in Göttingen minipigs against a whole-body exposure to 4.1mg/m(3) of sarin (GB) vapor, which produced lethality over 60min. Since the toxicity of nerve agent is concentration-dependent, in the present study, we investigated the toxic effects of an almost 3-fold higher rate of GB vapor exposure and the ability of Hu BChE to protect minipigs against this exposure. Male minipigs were subjected to: (1) air exposure; (2) GB vapor exposure; or (3) pretreatment with 7.5mg/kg of Hu BChE by i.m. injection, 24h prior to whole-body exposure to 11.4mg/m(3) of GB vapor for 10min. Electrocardiogram, electroencephalogram, and pupil size were monitored throughout exposure. Blood drawn before and throughout exposure was analyzed for blood gases, electrolytes, metabolites, acetylcholinesterase and BChE activities, and amount of GB bound to red blood cells and plasma. A novel finding was that saline-treated animals exposed to GB vapor did not develop any seizures, but manifested a variety of cardiac and whole blood toxic signs and rapidly died due to respiratory failure. Strikingly, pre-treatment with 7.5mg/kg of Hu BChE not only prevented lethality, but also avoided all cardiac toxic signs manifested in the non-treated cohort. Thus, Hu BChE alone can serve as an effective prophylactic countermeasure versus a lethal high-dose exposure to GB vapor. Published by Elsevier Ireland Ltd.

Aging pathways for organophosphate-inhibited human butyrylcholinesterase, including novel pathways for isomalathion, resolved by mass spectrometry.

PubMed

Li, He; Schopfer, Lawrence M; Nachon, Florian; Froment, Marie-Thérèse; Masson, Patrick; Lockridge, Oksana

2007-11-01

Some organophosphorus compounds are toxic because they inhibit acetylcholinesterase (AChE) by phosphylation of the active site serine, forming a stable conjugate: Ser-O-P(O)-(Y)-(XR) (where X can be O, N, or S and Y can be methyl, OR, or SR). The inhibited enzyme can undergo an aging process, during which the X-R moiety is dealkylated by breaking either the P-X or the X-R bond depending on the specific compound, leading to a nonreactivatable enzyme. Aging mechanisms have been studied primarily using AChE. However, some recent studies have indicated that organophosphate-inhibited butyrylcholinesterase (BChE) may age through an alternative pathway. Our work utilized matrix-assisted laser desorption/ionization-time-of-flight mass spectrometry to study the aging mechanism of human BChE inhibited by dichlorvos, echothiophate, diisopropylfluorophosphate (DFP), isomalathion, soman, sarin, cyclohexyl sarin, VX, and VR. Inhibited BChE was aged in the presence of H2O18 to allow incorporation of (18)O, if cleavage was at the P-X bond. Tryptic-peptide organophosphate conjugates were identified through peptide mass mapping. Our results showed no aging of VX- and VR-treated BChE at 25 degrees C, pH 7.0. However, BChE inhibited by dichlorvos, echothiophate, DFP, soman, sarin, and cyclohexyl sarin aged exclusively through O-C bond cleavage, i.e., the classical X-R scission pathway. In contrast, isomalathion aged through both X-R and P-X pathways; the main aged product resulted from P-S bond cleavage and a minor product resulted from O-C and/or S-C bond cleavage.

A High-Throughput UHPLC-MS/MS Method for the Quantification of Five Aged Butyrylcholinesterase Biomarkers from Human Exposure to Organophosphorus Nerve Agents

PubMed Central

Graham, Leigh Ann; Johnson, Darryl; Carter, Melissa D.; Stout, Emily G.; Erol, Huseyin A.; Isenberg, Samantha L.; Mathews, Thomas P.; Thomas, Jerry D.; Johnson, Rudolph C.

2017-01-01

Organophosphorus nerve agents (OPNAs) are toxic compounds that are classified as prohibited Schedule 1 chemical weapons. In the body, OPNAs bind to butyrylcholinesterase (BChE) to form nerve agent adducts (OPNA-BChE). OPNA-BChE adducts can provide a reliable, long-term protein biomarker for assessing human exposure. A major challenge facing OPNA-BChE detection is hydrolysis (aging), which can continue to occur after a clinical specimen has been collected. During aging, the o-alkyl phosphoester bond hydrolyzes, and the specific identity of the nerve agent is lost. To better identify OPNA exposure events, a high throughput method for the detection of five aged OPNA-BChE adducts was developed. This is the first diagnostic panel to allow for the simultaneous quantification of any Chemical Weapons Convention Schedule 1 OPNA by measuring the aged adducts methyl phosphonate (MeP-BChE), ethyl phosphonate (EtP-BChE), propyl phosphonate (PrP-BChE), ethyl phosphoryl (ExP-BChE), phosphoryl (P-BChE), and unadducted BChE. The calibration range for all analytes is 2.00 – 250. ng/mL, which is consistent with similar methodologies used to detect unaged OPNA-BChE adducts. Each analytical run is three minutes making the time to first unknown results, including calibration curve and quality controls, less than one hour. Analysis of commercially purchased individual serum samples demonstrated no potential interferences with detection of aged OPNA-BChE adducts, and quantitative measurements of endogenous levels of BChE were similar to those previously reported in other OPNA-BChE adduct assays. PMID:27572107

Plants as a source of butyrylcholinesterase variants designed for enhanced cocaine hydrolase activity.

PubMed

Larrimore, Katherine E; Barcus, Matthew; Kannan, Latha; Gao, Yang; Zhan, Chang-Guo; Brimijoin, Stephen; Mor, Tsafrir

2013-03-25

Cocaine addiction affects millions of people with disastrous personal and social consequences. Cocaine is one of the most reinforcing of all drugs of abuse, and even those who undergo rehabilitation and experience long periods of abstinence have more than 80% chance of relapse. Yet there is no FDA-approved treatment to decrease the likelihood of relapse in rehabilitated addicts. Recent studies, however, have demonstrated a promising potential treatment option with the help of the serum enzyme butyrylcholinesterase (BChE), which is capable of breaking down naturally occurring (-)-cocaine before the drug can influence the reward centers of the brain or affect other areas of the body. This activity of wild-type (WT) BChE, however, is relatively low. This prompted the design of variants of BChE which exhibit significantly improved catalytic activity against (-)-cocaine. Plants are a promising means to produce large amounts of these cocaine hydrolase variants of BChE, cheaply, safely with no concerns regarding human pathogens and functionally equivalent to enzymes derived from other sources. Here, in expressing cocaine-hydrolyzing mutants of BChE in Nicotiana benthamiana using the MagnICON virus-assisted transient expression system, and in reporting their initial biochemical analysis, we provide proof-of-principle that plants can express engineered BChE proteins with desired properties. Copyright © 2012 Elsevier Ireland Ltd. All rights reserved.

Butyrylcholinesterase gene transfer in obese mice prevents postdieting body weight rebound by suppressing ghrelin signaling

PubMed Central

Chen, Vicky Ping; Gao, Yang; Geng, Liyi; Brimijoin, Stephen

2017-01-01

The worldwide prevalence of obesity is increasing at an alarming rate but treatment options remain limited. Despite initial success, weight loss by calorie restriction (CR) often fails because of rebound weight gain. Postdieting hyperphagia along with altered hypothalamic neuro-architecture appears to be one direct cause of this undesirable outcome. In response to calorie deficiency the circulating levels of the appetite-promoting hormone, acyl-ghrelin, rise sharply. We hypothesize that proper modulation of acyl-ghrelin and its receptor’s sensitivity will favorably impact energy intake and reprogram the body weight set point. Here we applied viral gene transfer of the acyl-ghrelin hydrolyzing enzyme, butyrylcholinesterase (BChE), in a mouse model of diet-induced obesity. Our results confirmed that BChE overexpression decreased circulating acyl-ghrelin levels, suppressed CR-provoked ghrelin signaling, and restored central ghrelin sensitivity. In addition to maintaining healthy body weights, BChE treated mice had modest postdieting food intake and showed normal glucose homeostasis. Spontaneous activity and energy expenditure did not differ significantly between treated and untreated mice after body weight rebound, suggesting that BChE gene transfer did not alter energy expenditure in the long term. These findings indicate that combining BChE treatment with CR could be an effective approach in treating human obesity and aiding lifelong weight management. PMID:28973869

Malathion-induced inhibition of human plasma cholinesterase studied by the fluorescence spectroscopy method

NASA Astrophysics Data System (ADS)

Pavelkić, V. M.; Krinulović, K. S.; Savić, J. Z.; Ilić, M. A.

2008-05-01

The in vitro effect of technical grade malathion was assessed via the kinetic parameters of human plasma butyrylcholinesterase (BChE) using N-methylindoxyl acetate as a substrate for BChE. An inhibitor kinetics study demonstrated the existence of a biphasic inhibition curve, indicating high-and low-affinity binding sites of malathion. The IC 50 values as calculated from the experimental inhibition curves were 1.33 × 10-9 and 1.48 × 10-5 M for the high-and low-affinity binding sites, respectively; Hill’s analysis gave 1.29 × 10-9 and 1.38 × 10-6 M. The Cornish-Bowden plots and their secondary plots indicated that the nature of inhibition was of mixed type with the predominant competitive character of both affinity binding sites.

Design, synthesis, biological evaluation and docking study of 5-oxo-4,5-dihydropyrano[3,2-c]chromene derivatives as acetylcholinesterase and butyrylcholinesterase inhibitors.

PubMed

Khoobi, Mehdi; Alipour, Masoumeh; Sakhteman, Amirhossein; Nadri, Hamid; Moradi, Alireza; Ghandi, Mehdi; Emami, Saeed; Foroumadi, Alireza; Shafiee, Abbas

2013-10-01

A series of fused coumarins namely 5-oxo-4,5-dihydropyrano[3,2-c]chromenes linked to N-benzylpyridinium scaffold were synthesized and evaluated as acetylcholinesterase (AChE) and butyrylcholinesterase (BuChE) inhibitors. The 1-(4-fluorobenzyl)pyridinium derivative 6g showed the most potent anti-AChE activity (IC50 value=0.038 μM) and the highest AChE/BuChE selectivity (SI>48). The docking study permitted us to rationalize the observed structure-affinity relationships and to detect possible binding modes. Copyright © 2013 Elsevier Masson SAS. All rights reserved.

Hematological, biochemical effects, and self-reported symptoms in pesticide retailers.

PubMed

Rojas-García, Aurora Elizabeth; Medina-Díaz, Irma Martha; Robledo-Marenco, María de Lourdes; Barrón-Vivanco, Briscia Socorro; Girón-Pérez, Manuel Iván; Velázquez-Fernández, Jesús Bernardino; González-Arias, Cyndia Azucena; Albores-Medina, Arnulfo; Quintanilla-Vega, Betzabet; Ostrosky-Wegman, Patricia; Rojas-García, María Consuelo; Pérez-Herrera, Norma Elena; López-Flores, Juan Fernando

2011-05-01

This study evaluates the effects of exposure to pesticides on the health of pesticide retailers. The study population comprised 83-male pesticide retailers and 98 controls. Serum butyrylcholinesterase levels and complete blood analysis were performed in a certified laboratory and each subject completed a structured questionnaire. Butyrylcholinesterase activity and hematological parameters such as hemoglobin and hematocrit were significantly lower in pesticide retailers than in control subjects. In contrast, platelet count as well as hepatic parameters such as glutamic-pyruvate transaminase and gamma-glutamyl transpeptidase activities was higher in pesticide retailers. Furthermore, pesticide retailers experienced burning sensations in the skin more frequently than controls. These preliminary results suggest the importance of evaluating further toxicological biomarkers in these populations.

Preparation, anticholinesterase activity and molecular docking of new lupane derivatives.

PubMed

Castro, María Julia; Richmond, Victoria; Romero, Carmen; Maier, Marta S; Estévez-Braun, Ana; Ravelo, Angel G; Faraoni, María Belén; Murray, Ana Paula

2014-07-01

A set of twenty one lupane derivatives (2-22) was prepared from the natural triterpenoid calenduladiol (1) by transformations on the hydroxyl groups at C-3 and C-16, and also on the isopropenyl moiety. The derivatives were tested for their inhibitory activity against acetylcholinesterase (AChE) and butyrylcholinesterase (BChE) and some structure-activity relationships were outlined with the aid of enzyme kinetic studies and docking modelization. The most active compound resulted to be 3,16,30-trioxolup-20(29)-ene (22), with an IC50 value of 21.5μM for butyrylcholinesterase, which revealed a selective inhibitor profile towards this enzyme. Copyright © 2014 Elsevier Ltd. All rights reserved.

Synthesis of some new 3-coumaranone and coumarin derivatives as dual inhibitors of acetyl- and butyrylcholinesterase.

PubMed

Alipour, Masoumeh; Khoobi, Mehdi; Nadri, Hamid; Sakhteman, Amirhossein; Moradi, Alireza; Ghandi, Mehdi; Foroumadi, Alireza; Shafiee, Abbas

2013-08-01

A novel series of coumarin and 3-coumaranone derivatives encompassing the phenacyl pyridinium moiety were synthesized and evaluated for their acetylcholinesterase (AChE) and butyrylcholinesterase (BuChE) inhibitory activity using Ellman's method. All compounds presented inhibitory activity against both AChE and BuChE in the micromolar range. The molecular docking simulations revealed that all compounds were dual binding site inhibitors of AChE. A kinetic study was performed and the mechanism of enzyme inhibition was proved to be of mixed type. All compounds were tested for their antioxidant activity and no significant activity was observed. © 2013 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

Synthesis and biological evaluation of novel tacrine derivatives and tacrine-coumarin hybrids as cholinesterase inhibitors.

PubMed

Hamulakova, Slavka; Janovec, Ladislav; Hrabinova, Martina; Spilovska, Katarina; Korabecny, Jan; Kristian, Pavol; Kuca, Kamil; Imrich, Jan

2014-08-28

A series of novel tacrine derivatives and tacrine-coumarin heterodimers were designed, synthesized, and biologically evaluated for their potential inhibitory effect on both acetylcholinesterase (AChE) and butyrylcholinesterase (BuChE). Of these compounds, tacrine-coumarin heterodimer 7c and tacrine derivative 6b were found to be the most potent inhibitors of human AChE (hAChE), demonstrating IC50 values of 0.0154 and 0.0263 μM. Ligands 6b, 6c, and 7c exhibited the highest levels of inhibitory activity against human BuChE (hBuChE), demonstrating IC50 values that range from 0.228 to 0.328 μM. Docking studies were performed in order to predict the binding modes of compounds 6b and 7c with hAChE/hBuChE.

Synthesis, biological evaluation and molecular modelling of diversely functionalized heterocyclic derivatives as inhibitors of acetylcholinesterase/butyrylcholinesterase and modulators of Ca2+ channels and nicotinic receptors.

PubMed

Marco, José L; de los Ríos, Cristóbal; García, Antonio G; Villarroya, Mercedes; Carreiras, M Carmo; Martins, Carla; Eleutério, Ana; Morreale, Antonio; Orozco, M; Luque, F Javier

2004-05-01

The synthesis and the biological activity of compounds 5-40 as inhibitors of acetylcholinesterase (AChE) and butyrylcholinesterase (BuChE), as well as modulators of voltage-dependent Ca(2+) channels and nicotinic receptors, are described. These molecules are tacrine analogues, which have been prepared from polyfunctionalized 6-amino-5-cyano-4H-pyrans, 6-amino-5-cyano-pyridines and 5-amino-2-aryl-3-cyano-1,3-oxazoles via Friedländer reaction with selected cycloalkanones. These compounds are moderate acetylcholinesterase and butyrylcholinesterase inhibitors, the BuChE/AChE selectivity of the most active molecules ranges from 10.0 (compound 29) to 76.9 (compound 16). Interestingly, the 'oxazolo-tacrine' derivatives are devoid of any activity. All compounds showed an important inhibitory effect on the nicotinic acetylcholine receptor. Most of them also blocked L-type Ca(2+) channels, and three of them, 64, 19 and 67, the non-L type of Ca(2+) channels. Molecular modelling studies suggest that these compounds might bind at the peripheral binding site of AChE, which opens the possibility to design inhibitors able to bind at both, the catalytic and peripheral binding sites of the enzyme.

Antioxidant, Acetylcholinesterase, Butyrylcholinesterase, and α-glucosidase Inhibitory Activities of Corchorus depressus

PubMed Central

Afzal, Samina; Chaudhry, Bashir Ahmad; Ahmad, Ashfaq; Uzair, Muhammad; Afzal, Khurram

2017-01-01

Background: Corchorus depressus (Cd) commonly known as Boa-phalee belonging to the family Tiliaceae having 50 genera and 450 species. Cd is not among the studied medicinal agent despite its potential in ethnopharmacology. Objectives: The present study investigated antioxidant, acetylcholinesterase (AChE), butyrylcholinesterase (BChE), and α-glucosidase inhibitory activities of Cd. The dichloromethane and methanolic extracts of the Cd were evaluated for biological activities such as antioxidant and enzyme inhibitory activities of AChE, BChE, and α-glucosidase. Materials and Methods: Antioxidant activity was evaluated by measuring free radical scavenging potential of Cd using 1,1-diphenyl-2-picrylhydrazyl. Enzyme inhibition activities were done by measuring optical density. Results: The methanol extract of roots of Cd showed potential free radical scavenging activity 99% at concentration 16.1 μg/ml. AChE was inhibited by aerial part of dichloromethane fraction by 46.07% ± 0.45% while dichloromethane extracts of roots of Cd possessed significant activity against BChE with 86% inhibition compared with standard drug Eserine at concentration 0.5 mg/ml. The dichloromethane extract of roots of Cd showed 79% inhibition against α-glucosidase enzyme activity with IC50 62.8 ± 1.5 μg/ml. Conclusion: These findings suggest Cd as useful therapeutic option as antioxidant and inhibition of AChE, BChE, and α-glucosidase activities. SUMMARY The aerial parts and roots of Corchorus depressus (Cd) were extracted in dichloromethane and methanolThe extract of roots of Cd showed free radical scavenging activity 99% at concentration 16.1 mg/ml, Ach inhibition by aerial parts of dichloromethane fraction by 46.07%, and 79% inhibition against a-glucosidase enzyme activity with IC50 62.8 ± 1.5 mg/mlThe dichloromethane and methanolic extracts of Cd exhibited antioxidant inhibition of acetyl cholinesterase, butyrylcholinesterase, and a-glucosidase activities. Abbreviations used: DPPH: 1,1-diphenyl-2-picrylhydrazyl, Cd: Corchorus depressus, AChE: Acetylcholinesterase, BChE: Butyrylcholinesterase, AD: Alzheimer's disease. PMID:29200727

Magnetic Fe3O4@TiO2 Nanoparticles-based Test Strip Immunosensing Device for Rapid Detection of Phosphorylated Butyrylcholinesterase

DOE Office of Scientific and Technical Information (OSTI.GOV)

Ge, Xiaoxiao; Zhang, Weiying; Lin, Yuehe

2013-12-15

An integrated magnetic nanoparticles-based test-strip immunosensing device was developed for rapid and sensitive quantification of phosphorylated butyrylcholinesterase (BChE), the biomarker of exposure to organophosphous pesticides (OP), in human plasma. In order to overcome the difficulty in scarce availability of OP-specific antibody, here magnetic Fe3O4@TiO2 nanoparticles were used and adsorbed on the test strip through a small magnet inserted in the device to capture target OP-BChE through selective binding between TiO2 and OP moiety. Further recognition was completed by horseradish peroxidase (HRP) and anti-BChE antibody (Ab) co-immobilized gold nanoparticles (GNPs). Their strong affinities among Fe3O4@TiO2, OP-BChE and HRP/Ab-GNPs were characterized bymore » quartz crystal microbalance (QCM), surface plasmon resonance (SPR) and square wave voltammetry (SWV) measurements. After cutting off from test strip, the resulted immunocomplex (HRP/Ab-GNPs/OP-BChE/Fe3O4@TiO2) was measured by SWV using a screen printed electrode under the test zone. Greatly enhanced sensitivity was achieved by introduction of GNPs to link enzyme and antibody at high ratio, which amplifies electrocatalytic signal significantly. Moreover, the use of test strip for fast immunoreactions reduces analytical time remarkably. Coupling with a portable electrochemical detector, the integrated device with advanced nanotechnology displays great promise for sensitive, rapid and in-filed on-site evaluation of OP poisoning.« less

Interaction of Triton X-100 with acyl pocket of butyrylcholinesterase: effect on esterase activity and inhibitor sensitivity of the enzyme.

PubMed

Jaganathan, L; Boopathy, R

1998-06-01

The effect of non-ionic detergents like Triton X-100, Lubrol PX, Brij 35 and Tween 80 on the esterase activity and inhibitor sensitivity of human serum butyrylcholinesterase (BuChE) were studied. The results showed that though BuChE is not a detergent dependent enzyme, the esterase activity and inhibitor sensitivity of it can be modulated by the presence of detergents. All the detergents caused a marginal activation of the esterase activity. The presence of Lubrol PX, Brij 35 or Tween 80 did not affect the 50% molar inhibition concentration (IC50) of the inhibitors tested. But in the presence of Triton X-100 the IC50 values were increased for neostigmine, eserine and tetraisopropylpyrophosphoramide (acylation site interacting inhibitors), whereas for inhibitors like ethopropazine, imipramine and procainamide (choline binding pocket specific inhibitors) the IC50 values were unaltered. In addition, in the presence of Triton X-100 the bimolecular reaction constant for phosphorylation reaction (ki) of BuChE for the acyl pocket specific tetraisopropylpyrophosphoramide was reduced. Triton X-100 partially protected BuChE against this tetraisopropylpyrophosphoramide inactivation. These results indicate that Triton X-100 by interacting with the acyl pocket hydrophobic region is able to activate the esterase activity of BuChE. Further it reduces the capacity of the enzyme to react with inhibitors that inactivate it by interacting with the serine residue of the acylation site.

Long-acting anticholinesterases for myasthenia gravis: synthesis and activities of quaternary phenylcarbamates of neostigmine, pyridostigmine and physostigmine

PubMed Central

Yu, Qian-sheng; Holloway, Harold W.; Luo, Weiming; Lahiri, Debomoy K.; Brossi, Arnold; Greig, Nigel H.

2010-01-01

The N-monophenylcarbamate analogues of neostigmine methyl sulfate (6) and pyridostigmine bromide (8) together with their precursors (5), (7), and the N(1)-methylammonium analogues of (−)-phenserine (12), (−)-tolserine (14), (−)-cymserine (16) and (−)-phenethylcymserine (18) were synthesized to produce long-acting peripheral inhibitors of acetylcholinesterase or butyrylcholinesterase. Evaluation of their cholinesterase inhibition against human enzyme ex vivo demonstrated that, whereas compounds 5–8 possessed only marginal activity, 12, 14, 16 and 18 proved to be potent anticholinesterases. An extended duration of cholinesterase inhibition was determined in rodent, making them of potential interest as long-acting agents for myasthenia gravis. PMID:20627738

Synthesis and preliminary biological evaluations of (+)-isocampholenic acid-derived amides.

PubMed

Grošelj, Uroš; Golobič, Amalija; Knez, Damijan; Hrast, Martina; Gobec, Stanislav; Ričko, Sebastijan; Svete, Jurij

2016-08-01

The synthesis of two novel (+)-isocampholenic acid-derived amines has been realized starting from commercially available (1S)-(+)-10-camphorsulfonic acid. The novel amines as well as (+)-isocampholenic acid have been used as building blocks in the construction of a library of amides using various aliphatic, aromatic, and amino acid-derived coupling partners using BPC and CDI as activating agents. Amide derivatives have been assayed against several enzymes that hold potential for the development of new drugs to battle bacterial infections and Alzheimer's disease. Compounds 20c and 20e showed promising selective sub-micromolar inhibition of human butyrylcholinesterase [Formula: see text] ([Formula: see text] values [Formula: see text] and [Formula: see text], respectively).

Preparation, in vitro screening and molecular modelling of symmetrical bis-quinolinium cholinesterase inhibitors--implications for early myasthenia gravis treatment.

PubMed

Komloova, Marketa; Musilek, Kamil; Horova, Anna; Holas, Ondrej; Dohnal, Vlastimil; Gunn-Moore, Frank; Kuca, Kamil

2011-04-15

This paper describes the preparation and in vitro evaluation of 18 newly prepared bis-quinolinium inhibitors on human recombinant acetylcholinesterase (AChE) and human plasmatic butyrylcholinesterase (BChE). Their inhibitory (IC(50)) and was compared to the chosen standards ambenonium dichloride, edrophonium chloride, BW284c51 and ethopropazine hydrochloride. One novel compound was found to be a promising inhibitor of hAChE (in nM range) and was better than edrophonium chloride or BW284c51, but was worse than ambenonium chloride. This compound also showed selectivity towards hAChE and it was confirmed as a non-competitive inhibitor of hAChE by kinetic analysis. A molecular modelling study further confirmed its binding to the peripheral active site of hAChE via apparent π-π or π-cationic interactions. Copyright © 2011 Elsevier Ltd. All rights reserved.

Effect of rivastigmine or memantine add-on therapy is affected by butyrylcholinesterase genotype in patients with probable Alzheimer's disease.

PubMed

Han, Hyun Jeong; Kwon, Jay C; Kim, Jung Eun; Kim, Shin Gyeom; Park, Jong-Moo; Park, Kyung Won; Park, Key Chung; Park, Kee Hyung; Moon, So Young; Seo, Sang Won; Choi, Seong Hye; Cho, Soo-Jin

2015-01-01

The K variant of butyrylcholinesterase (BCHE-K) exhibits a reduced acetylcholine-hydrolyzing capacity; so the clinical response to rivastigmine may differ in Alzheimer's disease (AD) patients with the BCHE-K gene. To investigate the clinical response to rivastigmine transdermal patch monotherapy or memantine plus rivastigmine transdermal patch therapy in AD patients based on the BCHE-K gene. A total of 146 probable AD patients consented to genetic testing for butyrylcholinesterase and underwent the final efficacy evaluations. Responders were defined as patients with an equal or better score on the Alzheimer's Disease Assessment Scale-cognitive subscale (ADAS-cog) at 16 weeks compared to their baseline score. BCHE-K carriers showed a lower responder rate on the ADAS-cog than non-carriers (38.2 vs. 61.7%, p = 0.02), and this trend was evident in AD patients with apolipoprotein E ε 4 (35 vs. 60.7%, p = 0.001). The presence of the BCHE-K allele predicted a worse response on the ADAS-cog (odds ratio 0.35, 95% confidence interval 0.14-0.87), after adjusting for demographic and baseline cognitive and functional variables. The BCHE-K genotype may be related to a poor cognitive response to rivastigmine patch or memantine add-on therapy, especially in the presence of apolipoprotein E ε 4.

Efficacy of human serum butyrylcholinesterase against sarin vapor.

PubMed

Saxena, Ashima; Sun, Wei; Dabisch, Paul A; Hulet, Stanley W; Hastings, Nicholas B; Jakubowski, Edward M; Mioduszewski, Robert J; Doctor, Bhupendra P

2008-09-25

Human serum butyrylcholinesterase (Hu BChE) is currently under advanced development as a pretreatment drug for organophosphate (OP) poisoning in humans. It was shown to protect mice, rats, guinea pigs, and monkeys against multiple LD(50) challenges of OP nerve agents by i.v. or s.c. bolus injections. Since inhalation is the most likely route of exposure to OP nerve agents on the battlefield or in public places, the aim of this study was to evaluate the efficacy of Hu BChE against whole-body inhalation exposure to sarin (GB) vapor. Male Göttingen minipigs were subjected to one of the following treatments: (1) air exposure; (2) GB vapor exposure; (3) pretreatment with 3 mg/kg of Hu BChE followed by GB vapor exposure; (4) pretreatment with 6.5 mg/kg of Hu BChE followed by GB vapor exposure; (5) pretreatment with 7.5 mg/kg of Hu BChE followed by GB vapor exposure. Hu BChE was administered by i.m. injection, 24h prior to whole-body exposure to GB vapor at a concentration of 4.1 mg/m(3) for 60 min, a dose lethal to 99% of untreated exposed pigs (LCt99). EEG, ECG, and pupil size were monitored throughout exposure, and blood drawn from a surgically implanted jugular catheter before and throughout the exposure period, was analyzed for acetylcholinesterase (AChE) and BChE activities, and the amount of GB present in plasma. All animals exposed to GB vapor alone or pretreated with 3 or 6.5 mg/kg of Hu BChE, died following exposure to GB vapor. All five animals pretreated with 7.5 mg/kg of Hu BChE survived the GB exposure. The amount of GB bound in plasma was 200-fold higher compared to that from plasma of pigs that did not receive Hu BChE, suggesting that Hu BChE was effective in scavenging GB in blood. Additionally, pretreatment with 7.5 mg/kg of Hu BChE prevented cardiac abnormalities and seizure activity observed in untreated animals and those treated with lower doses of Hu BChE.

New derivatives of 3,4-dihydroisoquinoline-3-carboxylic acid with free-radical scavenging, D-amino acid oxidase, acetylcholinesterase and butyrylcholinesterase inhibitory activity.

PubMed

Solecka, Jolanta; Guśpiel, Adam; Postek, Magdalena; Ziemska, Joanna; Kawęcki, Robert; Lęczycka, Katarzyna; Osior, Agnieszka; Pietrzak, Bartłomiej; Pypowski, Krzysztof; Wyrzykowska, Agata

2014-09-30

A series of 3,4-dihydroisoquinoline-3-carboxylic acid derivatives were synthesised and tested for their free-radical scavenging activity using 2,2-diphenyl-1-picrylhydrazyl radical (DPPH·), 2,2'-azino-bis(3-ethylbenzothiazoline-6-sulfonic acid) radical (ABTS·+), superoxide anion radical (O2·-) and nitric oxide radical (·NO) assays. We also studied d-amino acid oxidase (DAAO), acetylcholinesterase (AChE) and butyrylcholinesterase (BuChE) inhibitory activity. Almost each of newly synthesised compounds exhibited radical scavenging capabilities. Moreover, several compounds showed moderate inhibitory activities against DAAO, AChE and BuChE. Compounds with significant free-radical scavenging activity may be potential candidates for therapeutics used in oxidative-stress-related diseases.

Inhibitors of Acetylcholinesterase and Butyrylcholinesterase Meet Immunity

PubMed Central

Pohanka, Miroslav

2014-01-01

Acetylcholinesterase (AChE) inhibitors are widely used for the symptomatic treatment of Alzheimer’s disease and other dementias. More recent use is for myasthenia gravis. Many of these inhibitors interact with the second known cholinesterase, butyrylcholinesterase (BChE). Further, evidence shows that acetylcholine plays a role in suppression of cytokine release through a “cholinergic anti-inflammatory pathway” which raises questions about the role of these inhibitors in the immune system. This review covers research and discussion of the role of the inhibitors in modulating the immune response using as examples the commonly available drugs, donepezil, galantamine, huperzine, neostigmine and pyridostigmine. Major attention is given to the cholinergic anti-inflammatory pathway, a well-described link between the central nervous system and terminal effector cells in the immune system. PMID:24893223

Synthesis, characterization and cholinesterase enzymes inhibitory activity of 1-[3-methyl-5-(2,6,6-trimethyl-cyclohex-1-enyl)-4,5-dihydro-pyrazol-1-yl]-ethanone

NASA Astrophysics Data System (ADS)

Mehdi, Sayed Hasan; Ghalib, Raza Murad; Hashim, Rokiah; da Silva, M. Fátima C. Guedes; Sulaiman, Othman; Murugaiyah, Vikneswaran; Marimuthu, Mani Maran; Naqvi, Mehnaz

2013-10-01

The crystal structure of the title compound, 1-[3-methyl-5-(2,6,6-trimethyl-cyclohex-1-enyl)-4,5-dihydro-pyrazol-1-yl]-ethanone has been determined by single crystal X-ray diffraction. It crystallizes in the orthorhombic space group P212121. The FTIR as well as the 1H and 13C NMR spectra of the compound were also recorded and briefly discussed. Compound 1 demonstrated good inhibitory activity against butyrylcholinesterase (BChE; IC50 = 46.42 μM) comparable to physostigmine. However it showed moderate inhibitory activity against acetylcholinesterase (AChE; IC50 = 157.31 μM). It showed moderate inhibitory activity against acetylcholinesterase and selective inhibitory activity towards butyrylcholinesterase enzyme.

Design, synthesis, docking study and biological evaluation of some novel tetrahydrochromeno [3',4':5,6]pyrano[2,3-b]quinolin-6(7H)-one derivatives against acetyl- and butyrylcholinesterase.

PubMed

Khoobi, Mehdi; Alipour, Masoumeh; Moradi, Alireza; Sakhteman, Amirhossein; Nadri, Hamid; Razavi, Seyyede Faeze; Ghandi, Mehdi; Foroumadi, Alireza; Shafiee, Abbas

2013-10-01

Novel hybrid derivatives of two known scaffolds; tetrahydroaminoquinoline and coumarin were synthesized and evaluated for both acetylcholinesterase (AChE) and butyrylcholinesterase (BuChE) activities. By means of an efficient nanocatalyst, the reaction time for the syntheses of the target compounds was reduced. Subsequently, Ellman's modified method was used to evaluate the enzyme inhibitory activity of the synthesized structures. It was observed that most hybrid structures were moderate to potent inhibitors of AChE compared to Tacrine as the reference drug among which 7f with 4-fluorophenyl substituent was the most active compound (IC50=5 nM). Copyright © 2013 Elsevier Masson SAS. All rights reserved.

Synthesis, kinetic studies and molecular modeling of novel tacrine dimers as cholinesterase inhibitors.

PubMed

de Aquino, Roney Anderson Nascimento; Modolo, Luzia Valentina; Alves, Rosemeire Brondi; de Fátima, Ângelo

2013-12-28

This study presents the synthesis of 15 new tacrine dimers as well as the Ki and IC50 results, studies of the kinetic mechanism, and molecular docking analysis of the dimers in relation to the cholinesterases hAChE, hBChE, EeAChE and eqBChE. In addition to spectroscopic characterization, X-ray structure determination was performed for two of the new compounds. These new dimers were found to be mixed nanomolar inhibitors of the evaluated targets with a broad and significant selectivity profile, and these properties are dependent on both the type of the linker and the volume of the hydroacridine alicyclic ring. The results indicate that the aromatic linkers play a significant role in generating specific interactions with the half-gorge region of the catalytic center. Thus, these types of linkers can positively modulate the electronic properties of the tacrine dimers studied with an improvement of their cholinesterase inhibition activity.

Enzyme-linked immunosorbent assay for detection of organophosphorylated butyrylcholinesterase: A biomarker of exposure to organophosphate agents

DOE Office of Scientific and Technical Information (OSTI.GOV)

Wang, Liming; Du, Dan; Lu, Donglai

2011-05-05

A sandwich enzyme-linked immunosorbent assay (sELISA) is developed for detection of organophosphorylated butyrylcholinesterase (OP-BChE), a potential biomarker for human exposure to organophosphate insecticides and nerve agents. A pair of antibodies specific to OP-BChE adduct were identified through systematic screening of several anti BChE antibodies (anti-BChE) and anti-phosphoserine antibodies (anti-Pser) from different sources. The selected anti-BChE (set as capture antibody) antibodies recognize both phosphorylated and nonphosphorylated BChE. These antibodies can therefore be used to capture both BChE and OP-BChE from the sample matrices. The anti- Pser (set as detecting antibody) was used to recognize the OP moiety of OP-BChE adducts. Withmore » the combination of the selected antibody pair, several key parameters (such as the concentration of anti-BChE and anti-Pser, and the blocking agent) were optimized to enhance the sensitivity and selectivity of the sELISA. Under the optimal conditions, the sELISA has shown a wide linear range from 0.03 nM to 30 nM, with a detection limit of 0.03 nM. Furthermore, the sELISA was successfully applied to detect OP-BChE using in-vitro biological samples such as rat plasma spiked with OP-BChE with excellent adduct recovery (z>99 %). These results demonstrate that this novel approach holds great promise to develop an ELISA kit and offers a simple and cost-effective tool for screening/evaluating exposure to organophosphate insecticides and nerve agents.« less

Novel cucurbitane triterpenoids and anti-cholinesterase activities of constituents from Momordica charantia L.

PubMed

Kuanhuta, Wichut; Aree, Thammarat; Pornpakakul, Surachai; Sawasdee, Pattara

2014-06-01

The C-19 epimers of 5beta,19-epoxycucurbita-6,23(E),25(26)-triene-3f,19-diol (1) and 5/,19-epoxy-25-methoxycucurbita-6,23-diene-3beta,19-diol (2) along with (19R,23E)-5beta,19-epoxy-19-methoxycucurbita-6,23,25-trien-3beta-ol (3), (23E)-5beta,19-epoxycucurbita-6,23-diene-3beta,25-diol (4), ligballinol (5), charantin (6) and momordicoside K(7) were isolated from the green fruits of Momordica charantia. The (S)-epimers of 1 and 2 are the first reports in nature. The acetyl- and butyryl-cholinesterase inhibitory activities of the isolated compounds were evaluated, and 5 showed the highest activity of these compounds against butyrylcholinesterase (IC50 = 32.20 microM) with a reversible and non-competitive inhibition mode.

Oxidation at C-16 enhances butyrylcholinesterase inhibition in lupane triterpenoids.

PubMed

Castro, María Julia; Richmond, Victoria; Faraoni, María Belén; Murray, Ana Paula

2018-05-17

A set of triterpenoids with different grades of oxidation in the lupane skeleton were prepared and evaluated as cholinesterase inhibitors. Allylic oxidation with selenium oxide and Jones's oxidation were employed to obtain mono-, di- and tri-oxolupanes, starting from calenduladiol (1) and lupeol (3). All the derivatives showed a selective inhibition of butyrylcholinesterase over acetylcholinesterase (BChE vs. AChE). A kinetic study proved that compounds 2 and 9, the more potent inhibitors of the series, act as competitive inhibitors. Molecular modeling was used to understand their interaction with BChE, the role of carbonyl at C-16 and the selectivity towards this enzyme over AChE. These results indicate that oxidation at C-16 of the lupane skeleton is a key transformation in order to improve the cholinesterase inhibition of these compounds. Copyright © 2018 Elsevier Inc. All rights reserved.

Protection by butyrylcholinesterase against organophosphorus poisoning in nonhuman primates. (Reannouncement with new availability information)

DOE Office of Scientific and Technical Information (OSTI.GOV)

Broomfield, C.A.; Maxwell, D.M.; Solana, R.P.

1991-12-31

Butyrylcholinesterase (BuChE) was examined as an in vivo exogenous scavenger for highly toxic organophosphorus (OP) poisons. Protection studies with equine BuChE were carried out in rhesus monkeys trained to perform a Serial Probe Recognition task. The pharmacokinetics of equine BuChE administered i.v. in rhesus monkeys revealed an elimination T1/2 of -620 hr. Animals given 503 nmol of BuChE i.v. and then challenged with 220 to 260 nmol of soman (two LD50; a lethal dose in untreated animals) all survived with no clinical signs of OP poisoning. Serial Probe Recognition performance was depressed after enzyme administration and at 1 hr postsoman.more » However, all monkeys performed the task at base-line levels at 8 hr after soman and throughout the remainder of the experimental period. Two different monkeys each were given two doses of sarin, 183 nmol/ dose (one LD50) after 460 nmol of BuChE. No signs were observed. A third group of monkeys given 253 or 340 nmol (three and four LD50, respectively) of soman after 460 nmol of BuChE required 1 mg/kg of atropine i.v. 1 0 min postsoman, but recovered completely within 24 hr. Our results indicate that BuChE has the required properties to function as a biological scavenger to protect against the pharmacological and behavioral toxicity of OP poisons. Exogenous scavenger, butyrylcholinesterase, nerve agent.« less

Reference values for acetyl and butyrylcholinesterases in cattle under actual management conditions, hepatic and renal function by application of chlorpyrifos.

PubMed

Ferré, Daniela M; Lentini, Valeria R; Romano, R Raquel; Ludueña, Hector R; Jotallán, Paola J; Gorla, Nora B M

2018-03-04

Chlorpyrifos is an anticholinesterase organophosphate insecticide widely used in Argentina in the production of food derived from animal, fruit and horticultural origin and is reported as a residue within these products. Local reference values for acetyl and butyrylcholinesterase were determined in Aberdeen Angus bovine and cross bred cattle (n = 25), a requirement to be able to evaluate toxicity of commercial organophosphate and carbamate formulations. The activity of cholinesterase enzymes presented an overall mean of 2,183.00 ± 485.6 IU L -1 for erythrocyte acetylcholinesterase and 203.1 ± 42.06 IU L -1 for plasma butyrylcholinesterase, which are used as reference values for meat steers within a system of intensive production in a semi-arid region. The toxic potential of chlorpyrifos in steers of the same breeds (n = 12) was assessed applying chlorpyrifos 15.00% Tipertox® in a single therapeutic dose of 7.50 mg kg -1 by topical route. Prior to application and then on day 1 and day 21 post-application, both blood cholinesterases, serum chlorpyrifos concentration by ultra-high resolution liquid chromatography with mass detector, analysis of blood counts, total proteins, liver enzymes, urea and creatinine were evaluated. The mean plasma concentration of chlorpyrifos was 27.90 ug L -1 at 24 h. The findings indicate that the therapeutic treatment of castrated male bovines treated with chlorpyrifos, applied by pour-on according to the manufacturer's instructions, does not cause changes in the variables evaluated.

Paraoxonase 1 and its relationship with pesticide biomarkers in indigenous Mexican farmworkers.

PubMed

Bernal-Hernández, Yael Yvette; Medina-Díaz, Irma Martha; Barrón-Vivanco, Briscia Socorro; Robledo-Marenco, María de Lourdes; Girón-Pérez, Manuel Iván; Pérez-Herrera, Norma Elena; Quintanilla-Vega, Betzabet; Cerda-Flores, Ricardo; Rojas-García, Aurora Elizabeth

2014-03-01

Biomarkers of pesticide toxicity and paraoxonase 1 (PON1) phenotype and genotypes were evaluated in indigenous Mexican farmworkers exposed mainly to organophosphate (OP) pesticides. Acetylcholinesterase, butyrylcholinesterase, and PON1 activities--arylesterase and CMPAase activities--were evaluated spectrophotometrically. PON1 55 and 192 polymorphisms were determined by real-time polymerase chain reaction. Hematological parameters were evaluated using a cytometer. Butyrylcholinesterase and arylesterase activities were lower in farmworkers, who also showed lower levels of leukocytes but higher percentages of lymphocytes when compared with the nonexposed group. Our results showed a high frequency of OP, high hydrolysis-related PON1 alleles (LL/QR and LL/RR) in the study population. An association was observed between CMPAase activity and PON1Q192R polymorphism. Our results suggest that pesticide exposure modifies biochemical and hematological biomarkers in the study population, and that the phenotype of PON1 (CMPAase) is a sensible susceptibility biomarker of OP pesticide toxicity.

Longitudinal Assessment of Blood Cholinesterase Activities over Two Consecutive Years among Latino Non-farmworkers and Pesticide-Exposed Farmworkers in North Carolina

PubMed Central

Quandt, Sara A; Pope, Carey N.; Chen, Haiying; Summers, Phillip; Arcury, Thomas A.

2015-01-01

Objective This study (1) describes patterns of whole blood total cholinesterase, acetylcholinesterase, and butyrylcholinesterase activities across the agricultural season, comparing farmworkers and non-farmworkers; and (2) explores differences between farmworkers' and non-farmworkers' likelihood of cholinesterase depression. Methods Blood samples from 210 Latino male farmworkers and 163 Latino workers with no occupational pesticide exposure collected eight times across two agricultural seasons were analyzed. Mean cholinesterase activity levels and depressions ≥15% were compared by month. Results Farmworkers had significantly lower total cholinesterase and butyrylcholinesterase activities in July and August and lower acetylcholinesterase activity in August. Farmworkers had significantly greater likelihood of cholinesterase depression for each cholinesterase measure across the agricultural season. Significance A repeated-measures design across two years with a non-exposed control group demonstrated anticholinesterase effects in farmworkers. Current regulations designed to prevent pesticide exposure are not effective. PMID:26247638

Design, synthesis and biological evaluation of novel 6H-benzo[c]chromen-6-one, and 7,8,9,10-tetrahydro-benzo[c]chromen-6-one derivatives as potential cholinesterase inhibitors.

PubMed

Gulcan, Hayrettin Ozan; Unlu, Serdar; Esiringu, Ilker; Ercetin, Tugba; Sahin, Yasemin; Oz, Demet; Sahin, Mustafa Fethi

2014-10-01

Hydroxylated 6H-benzo[c]chromen-6-one derivatives (i.e., urolithins) are the main bioavailable metabolites, and biomarkers of ellagitannins present in various nutrition. Although these dietaries, the sources of urolithins, are employed in folk medicine as cognitive enhancer in the treatment of Alzheimer's Disease, urolithins have negligible potential to inhibit acetylcholinesterase and butyrylcholinesterase enzymes, the validated targets of Alzheimer's Disease. Therefore, within this research, a series of 6H-benzo[c]chromen-6-one, and 7,8,9,10-tetrahydro-benzo[c]chromen-6-one derivatives has been designed, synthesized, and their biological activities were evaluated as potential acetylcholinesterase and butyrylcholinesterase inhibitors. The compounds synthesized exerted comparable activity in comparison to rivastigmine, galantamine, and donepezil both in in vitro and in vivo studies. Copyright © 2014 Elsevier Ltd. All rights reserved.

Synthesis, biological activity and molecular modeling of 4-fluoro-N-[ω-(1,2,3,4-tetrahydroacridin-9-ylamino)-alkyl]-benzamide derivatives as cholinesterase inhibitors.

PubMed

Szymański, P; Markowicz, M; Bajda, M; Malawska, B; Mikiciuk-Olasik, E

2012-12-01

The aim of this study was to synthesize and determine the biological activity of new derivatives of 4-fluorobenzoic acid and tetrahydroacridine towards inhibition of cholinesterases. Compounds were synthesized in condensation reaction between 9-aminoalkyl-tetrahydroacridines and the activated 4-fluorobenzoic acid. Properties towards inhibition of acetyl- and butyrylcholinesterase were estimated according to Ellman's spectrophotometric method. Among synthesized compounds the most active were compounds 4a and 4d. These compounds, in comparison with tacrine, were characterized by the similar values of IC50. Among all obtained compounds, 4d presented the highest selectivity towards inhibition of acetylcholinesterase. Molecular modeling studies revealed that all derivatives presented similar extended conformation in the gorge of acetylcholinesterase, however, there were 2 main conformations in the active center of butyrylcholinesterase: bent and extended conformation. © Georg Thieme Verlag KG Stuttgart · New York.

Longitudinal Assessment of Blood Cholinesterase Activities Over 2 Consecutive Years Among Latino Nonfarmworkers and Pesticide-Exposed Farmworkers in North Carolina.

PubMed

Quandt, Sara A; Pope, Carey N; Chen, Haiying; Summers, Phillip; Arcury, Thomas A

2015-08-01

This study (1) describes patterns of whole blood total cholinesterase, acetylcholinesterase, and butyrylcholinesterase activities across the agricultural season, comparing farmworkers and nonfarmworkers; and (2) explores differences between farmworkers' and non-farmworkers' likelihood of cholinesterase depression. Blood samples from 210 Latino male farmworkers and 163 Latino workers with no occupational pesticide exposure collected 8 times across 2 agricultural seasons were analyzed. Mean cholinesterase activity levels and depressions 15% or more were compared by month. Farmworkers had significantly lower total cholinesterase and butyrylcholinesterase activities in July and August and lower acetylcholinesterase activity in August. Farmworkers had significantly greater likelihood of cholinesterase depression for each cholinesterase measure across the agricultural season. A repeated-measures design across 2 years with a nonexposed control group demonstrated anticholinesterase effects in farmworkers. Current regulations designed to prevent pesticide exposure are not effective.

Bioactivity-guided fractionation for the butyrylcholinesterase inhibitory activity of furanocoumarins from Angelica archangelica L. roots and fruits.

PubMed

Wszelaki, Natalia; Paradowska, Katarzyna; Jamróz, Marta K; Granica, Sebastian; Kiss, Anna K

2011-09-14

Isolation and identification of the inhibitors of butyrylcholinesterase (BChE), obtained from the extracts of roots and fruits of Angelica archangelica L., are reported. Our results confirmed the weak inhibitory effect of Angelica roots on acetylcholinesterase activity. BChE inhibition was much more pronounced at a concentration of 100 μg/mL for hexane extracts and attained a higher rate than 50%. The TLC bioautography guided fractionation and spectroscopic analysis led to the isolation and identification of imperatorin from the fruit's hexane extract and of heraclenol-2'-O-angelate from the root's hexane extract. Both compounds showed significant BChE inhibition activity with IC(50) = 14.4 ± 3.2 μM and IC(50) = 7.5 ± 1.8 μM, respectively. Only C8-substituted and C5-unsubstituted furanocoumarins were active, which could supply information about the initial structures of specific BChE inhibitors.

[Prolonged neuromuscular block in a patient with butyrylcholinesterase deficiency].

PubMed

Mabboux, I; Hary, B; Courcelle, S; Ceppa, F; Delacour, H

2016-05-01

Succinylcholine is a neuromuscular block whose duration of action depends on rapid hydrolysis by butyrylcholinesterase (BChE). In patients with common BChE activities, succinylcholine duration of action is short (10min). BChE deficiency induces a slower hydrolysis of the drug and consequently prolonged neuromuscular block, leading to apnea. We report a case of prolonged neuromuscular block after administration of succinylcholine in a 14-year-old boy. Biological investigations revealed a marked BChE deficiency (1099U/L) related to the presence of three point mutations in the BCHE gene in a compound heterozygous state: p.Asp70Gly (rs1799807), p.Ala539Tyr (rs1803274), and p.Phe118Valfs*12 (rs398124632). The diagnosis of genetic BChE deficiency (OMIM 177400) was retained. This case is intended to present the pathophysiology of genetic BChE deficiency, its management, and the diagnostic strategy to be implemented. Copyright © 2016 Elsevier Masson SAS. All rights reserved.

Butyryl-cholinesterase is related to muscle mass and strength. A new biomarker to identify elderly subjects at risk of sarcopenia.

PubMed

Cacciatore, Francesco; Della-Morte, David; Basile, Claudia; Curcio, Francesco; Liguori, Ilaria; Roselli, Mario; Gargiulo, Gaetano; Galizia, Gianluigi; Bonaduce, Domenico; Abete, Pasquale

2015-01-01

To determine the relationship between Butyryl-cholinesterase (α-glycoprotein synthesized in the liver, b-CHE) and muscle mass and strength. Muscle mass by bioimpedentiometer and muscle strength by grip strength were evaluated in 337 elderly subjects (mean age: 76.2 ± 6.7 years) admitted to comprehensive geriatric assessment. b-CHE levels were lower in sarcopenic than in nonsarcopenic elderly subjects (p < 0.01). Linear regression analysis demonstrated that b-CHE is linearly related with grip strength and muscular mass both in men and women (r = 0.45 and r = 0.33, p < 0.01; r = 0.55 and r = 0.39, p < 0.01; respectively). Multivariate analysis confirms this analysis. b-CHE is related to muscle mass and strength in elderly subjects. Thus, b-CHE may be considered to be a fair biomarker for identifying elderly subjects at risk of sarcopenia.

Preparation, in vitro evaluation and molecular modelling of pyridinium-quinolinium/isoquinolinium non-symmetrical bisquaternary cholinesterase inhibitors.

PubMed

Komloova, Marketa; Horova, Anna; Hrabinova, Martina; Jun, Daniel; Dolezal, Martin; Vinsova, Jarmila; Kuca, Kamil; Musilek, Kamil

2013-12-15

Two series of non-symmetrical bisquaternary pyridinium-quinolinium and pyridinium-isoquinolinium compounds were prepared as molecules potentially applicable in myasthenia gravis treatment. Their inhibitory ability towards human recombinant acetylcholinesterase and human plasmatic butyrylcholinesterase was determined and the results were compared to the known effective inhibitors such as ambenonium dichloride, edrophonium bromide and experimental compound BW284C51. Two compounds, 1-(10-(pyridinium-1-yl)decyl)quinolinium dibromide and 1-(12-(pyridinium-1-yl)dodecyl)quinolinium dibromide, showed very promising affinity for acetylcholinesterase with their IC50 values reaching nM inhibition of acetylcholinesterase. These most active compounds also showed satisfactory selectivity towards acetylcholinesterase and they seem to be very promising as leading structures for further modifications and optimization. Two of the most promising compounds were examined in the molecular modelling study in order to find the possible interactions between the ligand and tested enzyme. Copyright © 2013 Elsevier Ltd. All rights reserved.

Resorcinol-, catechol- and saligenin-based bronchodilating β2-agonists as inhibitors of human cholinesterase activity.

PubMed

Bosak, Anita; Knežević, Anamarija; Gazić Smilović, Ivana; Šinko, Goran; Kovarik, Zrinka

2017-12-01

We investigated the influence of bronchodilating β2-agonists on the activity of human acetylcholinesterase (AChE) and usual, atypical and fluoride-resistant butyrylcholinesterase (BChE). We determined the inhibition potency of racemate and enantiomers of fenoterol as a resorcinol derivative, isoetharine and epinephrine as catechol derivatives and salbutamol and salmeterol as saligenin derivatives. All of the tested compounds reversibly inhibited cholinesterases with K i constants ranging from 9.4 μM to 6.4 mM and had the highest inhibition potency towards usual BChE, but generally none of the cholinesterases displayed any stereoselectivity. Kinetic and docking results revealed that the inhibition potency of the studied compounds could be related to the size of the hydroxyaminoethyl chain on the benzene ring. The additional π-π interaction of salmeterol's benzene ring and Trp286 and hydrogen bond with His447 probably enhanced inhibition by salmeterol which was singled out as the most potent inhibitor of all the cholinesterases.

Fundamental Reaction Pathway and Free Energy Profile for Butyrylcholinesterase-Catalyzed Hydrolysis of Heroin

PubMed Central

Qiao, Yan; Han, Keli; Zhan, Chang-Guo

2013-01-01

The pharmacological function of heroin requires an activation process which transforms heroin into 6-monoacetylmorphine (6-MAM) which is the most active form. The primary enzyme responsible for this activation process in human plasma is butyrylcholinesterase (BChE). The detailed reaction pathway of the activation process via BChE-catalyzed hydrolysis has been explored computationally, for the first time, in the present study by performing molecular dynamics simulation and first-principles quantum mechanical/molecular mechanical free energy calculations. It has been demonstrated that the whole reaction process includes acylation and deacylation stages. The acylation consists of two reaction steps, i.e. the nucleophilic attack on the carbonyl carbon of 3-acetyl group of heroin by the hydroxyl oxygen of Ser198 side chain and the dissociation of 6-MAM. The deacylation also consists of two reaction steps, i.e. the nucleophilic attack on the carbonyl carbon of the acyl-enzyme intermediate by a water molecule and the dissociation of the acetic acid from Ser198. The calculated free energy profile reveals that the second transition state (TS2) should be rate-determining. The structural analysis reveals that the oxyanion hole of BChE plays an important role in the stabilization of the rate-determining transition state TS2. The free energy barrier (15.9±0.2 or 16.1±0.2 kcal/mol) calculated for the rate-determining step is in good agreement with the experimentally-derived activation free energy (~16.2 kcal/mol), suggesting that the mechanistic insights obtained from the present computational study are reliable. The obtained structural and mechanistic insights could be valuable for use in future rational design of a novel therapeutic treatment of heroin abuse. PMID:23992153

Copper (II) and zinc (II) complexes with flavanone derivatives: Identification of potential cholinesterase inhibitors by on-flow assays.

PubMed

Sarria, André Lucio Franceschini; Vilela, Adriana Ferreira Lopes; Frugeri, Bárbara Mammana; Fernandes, João Batista; Carlos, Rose Maria; da Silva, Maria Fátima das Graças Fernandes; Cass, Quezia Bezerra; Cardoso, Carmen Lúcia

2016-11-01

Metal chelates strongly influence the nature and magnitude of pharmacological activities in flavonoids. In recent years, studies have shown that a promising class of flavanone-metal ion complexes can act as selective cholinesterase inhibitors (ChEIs), which has led our group to synthesize a new series of flavanone derivatives (hesperidin, hesperetin, naringin, and naringenin) complexed to either copper (II) or zinc (II) and to evaluate their potential use as selective ChEIs. Most of the synthesized complexes exhibited greater inhibitory activity against acetylcholinesterase (AChE) than against butyrylcholinesterase (BChE). Nine of these complexes constituted potent, reversible, and selective ChEIs with inhibitory potency (IC 50 ) and inhibitory constant (K i ) ranging from 0.02 to 4.5μM. Copper complexes with flavanone-bipyridine derivatives afforded the best inhibitory activity against AChE and BChE. The complex Cu(naringin)(2,2'-bipyridine) (11) gave IC 50 and K i values of 0.012±0.002 and 0.07±0.01μM for huAChE, respectively, which were lower than the inhibitory values obtained for standard galanthamine (IC 50 =206±30.0 and K i =126±18.0μM). Evaluation of the inhibitory activity of this complex against butyrylcholinesterase from human serum (huBChE) gave IC 50 and K i values of 8.0±1.4 and 2.0±0.1μM, respectively. A Liquid Chromatography-Immobilized Capillary Enzyme Reactor by UV detection (LC-ICER-UV) assay allowed us to determine the IC 50 and K i values and the type of mechanism for the best inhibitors. Copyright © 2016 Elsevier Inc. All rights reserved.

Pressure- and heat-induced inactivation of butyrylcholinesterase: evidence for multiple intermediates and the remnant inactivation process.

PubMed Central

Weingand-Ziade, A; Ribes, F; Renault, F; Masson, P

2001-01-01

The inactivation process of native (N) human butyrylcholinesterase (BuChE) by pressure and/or heat was found to be multi-step. It led to irreversible formation of an active intermediate (I) state and a denatured state. This series-inactivation process was described by expanding the Lumry-Eyring [Lumry, R. and Eyring, H. (1954) J. Phys. Chem. 58, 110-120] model. The intermediate state (I) was found to have a K(m) identical with that of the native state and a turnover rate (k(cat)) twofold higher than that of the native state with butyrylthiocholine as the substrate. The increased catalytic efficiency (k(cat)/K(m)) of I can be explained by a conformational change in the active-site gorge and/or restructuring of the water-molecule network in the active-site pocket, making the catalytic steps faster. However, a pressure/heat-induced covalent modification of native BuChE, affecting the catalytic machinery, cannot be ruled out. The inactivation process of BuChE induced by the combined action of pressure and heat was found to continue after interruption of pressure/temperature treatment. This secondary inactivation process was termed 'remnant inactivation'. We hypothesized that N and I were in equilibrium with populated metastable N' and I' states. The N' and I' states can either return to the active forms, N and I, or develop into inactive forms, N(')(in) and I(')(in). Both active N' and I' intermediate states displayed different rates of remnant inactivation depending on the pressure and temperature pretreatments and on the storage temperature. A first-order deactivation model describing the kinetics of the remnant inactivation of BuChE is proposed. PMID:11368776

PHOS-Select Iron Affinity beads enrich peptides for detection of organophosphorus adducts on albumin

PubMed Central

Jiang, Wei; Dubrovskii, Yaroslav A; Podolskaya, Ekaterina P; Murashko, Ekaterina A; Babakov, Vladimir; Nachon, Florian; Masson, Patrick; Schopfer, Lawrence M; Lockridge, Oksana

2013-01-01

Albumin is covalently modified by organophosphorus toxicants (OP) on tyrosine 411, but less than 1% of albumin is modified in humans by lethal OP doses that inhibit 95% of plasma butyrylcholinesterase. A method that enriches OP-modified albumin peptides could aid analysis of low dose exposures. Soman or chlorpyrifos oxon treated human plasma was digested with pepsin. Albumin peptides were enriched by binding to Fe3+ beads at pH 11 and eluted with pH 2.6 buffer. Similarly, mouse and guinea pig albumin modified by chlorpyrifos oxon were digested with pepsin and enriched by binding to Fe3+ beads. Peptides were identified by MALDI-TOF/TOF mass spectrometry. PHOS-select Iron Affinity beads specifically enriched albumin peptides VRY411TKKVPQVST and LVRY411TKKVPQVST in a pepsin digest of human plasma. The unmodified as well as OP-modified peptides bound to the beads. The binding capacity of 500 μl beads was the pepsin digest of 2.1 μL human plasma. The limit of detection was 0.2% of OP-modified albumin peptide in 0.43 μL plasma. Enrichment of OP-modified albumin peptides by binding to Fe3+ beads is a method with potential application to diagnosis of OP pesticide and nerve agent exposure in humans, mice, and guinea pigs. PMID:24187955

Post-exposure therapy with human butyrylcholinesterase following percutaneous VX challenge in guinea pigs.

PubMed

Mumford, Helen; E Price, Matthew; Lenz, David E; Cerasoli, Douglas M

2011-04-01

Human butyrylcholinesterase (huBuChE) has potential utility as a post-exposure therapy following percutaneous nerve agent poisoning as there is a slower absorption of agent by this route and hence a later onset of poisoning. METHODS. We used surgically implanted radiotelemetry devices to monitor heart rate, EEG, body temperature and locomotor activity in guinea pigs challenged with VX via the percutaneous route. RESULTS. Treatment with huBuChE (24.2 mg/kg, i.m.) at 30 or 120 min following percutaneous VX (~2.5 × LD(50)) protected 9 out of 10 animals from lethality. When i.m. huBuChE administration was delayed until the onset of observable signs of systemic cholinergic poisoning, only one out of six animals survived to 7 days. Survival increased to 50% when the same dose of huBuChE was given intravenously at the onset of signs of poisoning. This dose represents approximately 1/10th the stoichiometric equivalent of the dose of VX administered (0.74 mg/kg). Intramuscular administration of huBuChE (24.2 mg/kg) alone did not produce any changes in heart rate, brain electrical activity, temperature or locomotion compared to saline control. Survival following VX and huBuChE treatment was associated with minimal incapacitation and observable signs of poisoning, and the mitigation or prevention of detrimental physiological changes (e.g. seizure, bradycardia and hypothermia) observed in VX + saline-treated animals. At 7 days, cholinesterase activity in the erythrocytes and most brain areas of guinea pigs that received huBuChE at either 18 h prior to or 30 min following VX was not significantly different from that of naïve, weight-matched control animals. CONCLUSION. Percutaneous VX poisoning was successfully treated using post-exposure therapy with huBuChE bioscavenger. The opportunity for post-exposure treatment may have particular relevance in civilian settings, and this is a promising indication for the use of huBuChE.

Effects in vivo of iohexol and diatrizoate on human plasma acetyl- and butyryl-cholinesterase activity.

PubMed

Mironidou, M; Katsimba, D; Kokkas, B; Kaitartzis, C; Karamanos, G; Christopoulos, S

2001-03-01

The aim of this study was to evaluate the effects of two iodinate contrast agents (CA), iohexol and diatrizoate, on human plasma acetyl-(AC) and butyrylcholinesterase(BC) activity. Forty-eight patients (24 males and 24 females) scheduled for intravenous pyelography were randomly divided into four groups of 6 males and 6 females each, receiving as CA, respectively: iohexol (Omnipaque, Schering) 0.6 ml/kg body weight (G1); iohexol 1.2 mg/kg (G2); sodium and meglumine diatrizoate 58% (Urografin, Schering) 0.6 ml/kg (G3); sodium and meglumine diatrizoate 58% 1.2 ml/kg (G4). Blood samples were taken before and 5, 10, and 20 min after the injection. Enzymatic activity of AC and BC were measured by spectrophotometry. Plasma concentration of K, Na, Ca, and Mg was measured in all blood samples; blood pressure and plasma pH were measured after each sample collection. Statistical analysis was performed by Student's test. In G1 a reversible decrease of AC (12.9%) and BC (8.2%) plasma activity was observed at 10 min. In G2 a progressive decrease of AC (13.9%) and BC (18.4%) plasma activity was observed with a maximum at 20 min. In G3 a modest reversible decrease of BC plasma activity (5.4%) was observed. In G4 a modest progressive decrease of AC (7.3%) and BC (6.5%) plasma activities was observed. In all cases, AC and BC plasma activities remained within the normal range of values. Plasma concentration of K, Na, Ca, and Mg, as well as pH and systolic and diastolic pressure, did not show any change. No adverse effects was observed in our patients. Iohexol and diatrizoate induce in vivo a significant decrease of AC and BC plasma activities. The decrease is more pronounced for iohexol, a non ionic CA, which has a lower pharmacotoxicity than diatrizoate and adverse effects rate. No inference can be drawn about the relationship between plasma cholinesterase activity and adverse effects.

Aspirin Hydrolysis in Plasma Is a Variable Function of Butyrylcholinesterase and Platelet-activating Factor Acetylhydrolase 1b2 (PAFAH1b2)*

PubMed Central

Zhou, Gang; Marathe, Gopal K.; Hartiala, Jaana; Hazen, Stanley L.; Allayee, Hooman; Tang, W. H. Wilson; McIntyre, Thomas M.

2013-01-01

Aspirin is rapidly hydrolyzed within erythrocytes by a heterodimer of PAFAH1b2/PAFAH1b3 but also in plasma by an unidentified activity. Hydrolysis in both compartments was variable, with a 12-fold variation in plasma among 2226 Cleveland Clinic GeneBank patients. Platelet inhibition by aspirin was suppressed in plasma that rapidly hydrolyzed aspirin. Plasma aspirin hydrolysis was significantly higher in patients with coronary artery disease compared with control subjects (16.5 ± 4.4 versus 15.1 ± 3.7 nmol/ml/min; p = 3.4 × 10−8). A genome-wide association study of 2054 GeneBank subjects identified a single locus immediately adjacent to the BCHE (butyrylcholinesterase) gene associated with plasma aspirin hydrolytic activity (lead SNP, rs6445035; p = 9.1 × 10−17). However, its penetrance was low, and plasma from an individual with an inactivating mutation in BCHE still effectively hydrolyzed aspirin. A second aspirin hydrolase was identified in plasma, the purification of which showed it to be homomeric PAFAH1b2. This is distinct from the erythrocyte PAFAH1b2/PAFAH1b3 heterodimer. Inhibitors showed that both butyrylcholinesterase (BChE) and PAFAH1b2 contribute to aspirin hydrolysis in plasma, with variation primarily reflecting non-genetic variation of BChE activity. Therefore, aspirin is hydrolyzed in plasma by two enzymes, BChE and a new extracellular form of platelet-activating factor acetylhydrolase, PAFAH1b2. Hydrolytic effectiveness varies widely primarily from non-genetic variation of BChE activity that affects aspirin bioavailability in blood and the ability of aspirin to inhibit platelet aggregation. PMID:23508960

Human serum butyrylcholinesterase: in vitro and in vivo stability, pharmacokinetics, and safety in mice.

PubMed

Saxena, Ashima; Sun, Wei; Luo, Chunyuan; Doctor, Bhupendra P

2005-12-15

The use of exogenously administered cholinesterases (ChEs) as bioscavengers of highly toxic organophosphate (OP) nerve agents is now sufficiently well documented to make them a highly viable prophylactic treatment against this potential threat. Of the ChEs evaluated so far, human serum butyrylcholinesterase (HuBChE) is most suitable for human use. A dose of 200 mg (3 mg/kg) of HuBChE is envisioned as a prophylactic treatment in humans that can protect from an exposure of up to 2 x LD50 of soman. In addition to its use as a prophylactic for a variety of wartime scenarios, including covert actions, it also has potential use for first responders (civilians) reacting to terrorist nerve gas release. We recently, developed a procedure for the large-scale purification of HuBChE, which yielded approximately 6 g of highly purified enzyme from 120 kg of Cohn fraction IV-4. The enzyme had a specific activity of 700-750 U/mg and migrated as a single band on SDS-PAGE. To provide data for initiating an investigational new drug (IND) application for the use of this enzyme as a bioscavenger in humans, we established its pharmacokinetic properties, examined its safety in mice, and evaluated its shelf life at various temperatures. In mice administered various doses up to 90 mg/kg, enzyme activity reached peak levels in circulation at 10 and 24 h following i.p. and i.m. injections, respectively. The enzyme displayed a mean residence time (MRT) of 40-50 h, regardless of the route of administration or dose of injected enzyme. Mice were euthanized 2 weeks following enzyme administration and tissues were examined grossly or microscopically for possible toxic effects. Results suggest that HuBChE does not exhibit any toxicity in mice as measured by general observation, serum chemistry, hematology, gross or histologic tissue changes. The shelf life of this enzyme stored at 4, 25, 37, and 45 degrees C was determined in lyophilized form. The enzyme was found to be stable when stored in lyophilized form at -20, 4, 25, or 37 degrees C to date (2 years), as measured by specific activity and SDS polyacrylamide gel electrophoresis. The effect of storage on circulatory stability was determined by measuring MRT in mice; there was no change in the MRT of lyophilized enzyme stored at -20 degrees C to date (2 years). These results provide convincing data that HuBChE is a safe bioscavenger that can provide protection against all OP nerve agents. Efforts are now underway to prepare the required documentation for submission of an IND application to the United States Food and Drug Administration (USFDA).

Biomarkers of organophosphorus (OP) exposures in humans

PubMed Central

Marsillach, Judit; Richter, Rebecca J.; Kim, Jerry H.; Stevens, Richard C.; MacCoss, Michael J.; Tomazela, Daniela; Suzuki, Stephanie M.; Schopfer, Lawrence M; Lockridge, Oksana; Furlong, Clement E.

2011-01-01

There are ongoing events where aircraft engine lubricant containing tricresyl phosphates (TCPs) contaminates aircraft cabins. Some individuals have experienced tremors or other neurological symptoms that may last for many months following exposures. Mass spectrometric (MS) protocols are being developed to determine the percentage of “biomarker proteins” that are modified by such exposures, specifically on active site serines. Both plasma butyrylcholinesterase (BChE) and red cell acylpeptide hydrolase (APH) are readily inhibited by 2-(o-cresyl)-4H-1:3:2:benzodioxaphosphoran-2-one (CBDP) or phenyl saligenin cyclic phosphate (PSP) and have the potential to provide information about the level of exposure of an individual. We have developed immunomagnetic bead-based single-step purification protocols for both BChE and APH and have characterized the active site serine adducts of BChE by MS. PMID:21767566

Biomarkers of organophosphorus (OP) exposures in humans.

PubMed

Marsillach, Judit; Richter, Rebecca J; Kim, Jerry H; Stevens, Richard C; MacCoss, Michael J; Tomazela, Daniela; Suzuki, Stephanie M; Schopfer, Lawrence M; Lockridge, Oksana; Furlong, Clement E

2011-10-01

There are ongoing events where aircraft engine lubricant containing tricresyl phosphates (TCPs) contaminates aircraft cabins. Some individuals have experienced tremors or other neurological symptoms that may last for many months following exposures. Mass spectrometric (MS) protocols are being developed to determine the percentage of "biomarker proteins" that are modified by such exposures, specifically on active site serines. Both plasma butyrylcholinesterase (BChE) and red cell acylpeptide hydrolase (APH) are readily inhibited by 2-(ortho-cresyl)-4H-1,3,2-benzodioxaphosphoran-2-one (CBDP) or phenyl saligenin cyclic phosphate (PSP) and have the potential to provide information about the level of exposure of an individual. We have developed immunomagnetic bead-based single-step purification protocols for both BChE and APH and have characterized the active site serine adducts of BChE by MS. Copyright © 2011 Elsevier Inc. All rights reserved.

(-)-Epicatechin derivate from Orostachys japonicus as potential inhibitor of the human butyrylcholinesterase.

PubMed

Kim, Jang Hoon; Lee, Sang-Hyun; Lee, Hyun Woo; Sun, Ya Nan; Jang, Won-Hee; Yang, Seo-Young; Jang, Hae-Dong; Kim, Young Ho

2016-10-01

Cholinesterase inhibitors block the bioconversion of neurotransmitters by cholinesterase in the nervous system. Epicatechin derivatives (1, 3 and 5), polyphenols (6 and 7) from Orostachys japonicus, and catechin derivatives (2 and 4) from our in-house library were evaluated for their inhibitory activity on cholinesterase. Compound 5 exhibited IC50 values of 58.3±2.4 and 17.8±3.8μg/mL on AChE and BuChE, respectively. Compound 5 inhibited BuChE more strongly than AChE through a competitive behavior. In silico binding positions of 5 in the active site were predicted using Autodock 4.2 and processed in a 10000-ps molecular dynamics simulation to assess the stability of compound 5 binding. Copyright © 2016 Elsevier B.V. All rights reserved.

2-Hydroxyethyl substituted NHC precursors: Synthesis, characterization, crystal structure and carbonic anhydrase, α-glycosidase, butyrylcholinesterase, and acetylcholinesterase inhibitory properties

NASA Astrophysics Data System (ADS)

Erdemir, Fatoş; Barut Celepci, Duygu; Aktaş, Aydın; Taslimi, Parham; Gök, Yetkin; Karabıyık, Hasan; Gülçin, İlhami

2018-03-01

This study contains novel a serie synthesis of N-heterocyclic carbene (NHC) precursors that 2-hydroxyethyl substituted. The NHC precursors have been prepared from 1-(2- hydroxyethyl)benzimidazole and alkyl halides. The novel NHC precursors have been characterized by using 1H NMR, 13C NMR, FTIR spectroscopy and elemental analysis techniques. Molecular and crystal structures of 2a, 2d, 2e, 2f and 2g were obtained with single-crystal X-ray diffraction studies. These novel NHC precursor's derivatives effectively inhibited the α-glycosidase, cytosolic carbonic anhydrase I and II isoforms (hCA I and II), butyrylcholinesterase (BChE) and acetylcholinesterase (AChE). Inhibition constant (Ki) were found in the range of 0.30-9.22 nM for α-glycosidase, 13.90-41.46 nM for hCA I, 12.82-49.95 nM for hCA II, 145.82-882.01 nM for BChE, and 280.92-1370.01 nM for AChE, respectively.

Plant-expressed cocaine hydrolase variants of butyrylcholinesterase exhibit altered allosteric effects of cholinesterase activity and increased inhibitor sensitivity.

PubMed

Larrimore, Katherine E; Kazan, I Can; Kannan, Latha; Kendle, R Player; Jamal, Tameem; Barcus, Matthew; Bolia, Ashini; Brimijoin, Stephen; Zhan, Chang-Guo; Ozkan, S Banu; Mor, Tsafrir S

2017-09-05

Butyrylcholinesterase (BChE) is an enzyme with broad substrate and ligand specificities and may function as a generalized bioscavenger by binding and/or hydrolyzing various xenobiotic agents and toxicants, many of which target the central and peripheral nervous systems. Variants of BChE were rationally designed to increase the enzyme's ability to hydrolyze the psychoactive enantiomer of cocaine. These variants were cloned, and then expressed using the magnICON transient expression system in plants and their enzymatic properties were investigated. In particular, we explored the effects that these site-directed mutations have over the enzyme kinetics with various substrates of BChE. We further compared the affinity of various anticholinesterases including organophosphorous nerve agents and pesticides toward these BChE variants relative to the wild type enzyme. In addition to serving as a therapy for cocaine addiction-related diseases, enhanced bioscavenging against other harmful agents could add to the practicality and versatility of the plant-derived recombinant enzyme as a multivalent therapeutic.

GC-MS analysis of the antioxidant active fractions of Micromeria juliana with anticholinesterase activity.

PubMed

Oztürk, Mehmet; Kolak, Ufuk; Duru, Mehmet Emin; Harmandar, Mansur

2009-09-01

The aerial parts of Micromeria juliana (L.) Bentham ex Reichb. were extracted with light petroleum, acetone and methanol, successively. The antioxidant activity of different concentrations of the extracts was evaluated using different antioxidant tests, namely total antioxidant (lipid peroxidation inhibition activity), DPPH (1,1-diphenyl-2-picrylhydrazyl) radical scavenging, ferric reducing power, and metal chelating. Total antioxidant activity was determined using the beta-carotene-linoleic acid assay. Unexpectedly, the light petroleum extract exhibited strong lipid peroxidation inhibition activity. The extract was fractionated on a silica gel column and the antioxidant activity of the fractions was determined by the beta-carotene-linoleic assay at 25 microg/mL concentration. The fractions that exhibited more than 50% inhibition activity were analysed by GC and GC/MS; thus, the structure of fourteen compounds were elucidated. In addition, acetyl- and butyryl-cholinesterase inhibitory activities of the extracts were also determined in vitro. The light petroleum and acetone extracts were found to have mild butyrylcholinesterase inhibitory activity.

Increased serum butyrylcholinesterase activity in type IIb hyperlipidaemic patients.

PubMed

Kálmán, János; Juhász, Anna; Rakonczay, Zoltán; Abrahám, György; Zana, Marianna; Boda, Krisztina; Farkas, Tibor; Penke, Botond; Janka, Zoltán

2004-07-23

The inheritance of the apolipoprotein E4 (APOE4) allele has been shown to increase the plasma cholesterol level, but little information is as concerns the association of the APOE genotype and hyperlipidaemia and the activities of two serum enzymes, acetylcholinesterase (AChE) and butyrylcholinesterase (BChE). Blood samples from 55 type IIb hyperlipidaemic, non-demented patients and 55 age- and sex-matched controls were therefore examined in this pilot study. A significantly increased BChE activity was found in the serum of type IIb hyperlipidaemic patients, but the AChE activity did not differ significantly as compared with that in the control group. The APOE4 allele was significantly overrepresented among the hyperlipidaemic probands, but neither serum cholinesterase activity was affected by the dosage of the APOE4 gene. Our results point to a possible association between an abnormal lipid metabolism and the BChE activity and might have implications as regards the pathomechanism of both Alzheimer's and vascular dementias and the cholinesterase inhibitor therapy of dementing disorders.

Unexpected Reaction Pathway for butyrylcholinesterase-catalyzed inactivation of “hunger hormone” ghrelin

NASA Astrophysics Data System (ADS)

Yao, Jianzhuang; Yuan, Yaxia; Zheng, Fang; Zhan, Chang-Guo

2016-02-01

Extensive computational modeling and simulations have been carried out, in the present study, to uncover the fundamental reaction pathway for butyrylcholinesterase (BChE)-catalyzed hydrolysis of ghrelin, demonstrating that the acylation process of BChE-catalyzed hydrolysis of ghrelin follows an unprecedented single-step reaction pathway and the single-step acylation process is rate-determining. The free energy barrier (18.8 kcal/mol) calculated for the rate-determining step is reasonably close to the experimentally-derived free energy barrier (~19.4 kcal/mol), suggesting that the obtained mechanistic insights are reasonable. The single-step reaction pathway for the acylation is remarkably different from the well-known two-step acylation reaction pathway for numerous ester hydrolysis reactions catalyzed by a serine esterase. This is the first time demonstrating that a single-step reaction pathway is possible for an ester hydrolysis reaction catalyzed by a serine esterase and, therefore, one no longer can simply assume that the acylation process must follow the well-known two-step reaction pathway.

Simultaneous quantification of soman and VX adducts to butyrylcholinesterase, their aged methylphosphonic acid adduct and butyrylcholinesterase in plasma using an off-column procainamide-gel separation method combined with UHPLC-MS/MS.

PubMed

Liu, Chang-Cai; Huang, Gui-Lan; Xi, Hai-Ling; Liu, Shi-Lei; Liu, Jing-Quan; Yu, Hui-Lan; Zhou, Shi-Kun; Liang, Long-Hui; Yuan, Ling

2016-11-15

This work describes a novel and sensitive non-isotope dilution method for simultaneous quantification of organophosphorus nerve agents (OPNAs) soman (GD) and VX adducts to butyrylcholinesterase (BChE), their aged methylphosphonic acid (MeP) adduct and unadducted BChE in plasma exposed to OPNA. OPNA-BChE adducts were isolated with an off-column procainamide-gel separation (PGS) from plasma, and then digested with pepsin into specific adducted FGES * AGAAS nonapeptide (NP) biomarkers. The resulting NPs were detected by UHPLC-MS/MS MRM. The off-column PGS method can capture over 90% of BChE, MeP-BChE, VX-BChE and GD-BChE from their respective plasma materials. One newly designed and easily synthesized phosphorylated BChE nonapeptide with one Gly-to-Ala mutation was successfully reported to serve as internal standard instead of traditional isotopically labeled BChE nonapeptide. The linear range of calibration curves were from 1.00-200ngmL -1 for VX-NP, 2.00-200ngmL -1 for GD-NP and MeP-NP (R 2 ≥0.995), and 3.00-200ngmL -1 for BChE NP (R 2 ≥0.990). The inter-day precision had relative standard deviation (%RSD) of <8.89%, and the accuracy ranged between 88.9-120%. The limit of detection was calculated to be 0.411, 0.750, 0.800 and 1.43ngmL -1 for VX-NP, GD-NP, MeP-NP and BChE NP, respectively. OPNA-exposed quality control plasma samples were characterized as part of method validation. Investigation of plasma samples unexposed to OPNA revealed no baseline values or interferences. Using the off-column PGS method combined with UHPLC-MS/MS, VX-NP and GD-NP adducts can be unambiguously detected with high confidence in 0.10ngmL -1 and 0.50ngmL -1 of exposed human plasma respectively, only requiring 0.1mL of plasma sample and taking about four hours without special sample preparation equipment. These improvements make it a simple, sensitive and robust PGS-UHPLC-MS/MS method, and this method will become an attractive alternative to immunomagnetic separation (IMS) method and a useful diagnostic tool for retrospective detection of OPNA exposure with high confidence. Furthermore, using the developed method, the adducted BChE levels from VX and GD-exposed (0.10-100ngmL -1 ) plasma samples were completely characterized, and the fact that VX being more active and specific to BChE than GD was re-confirmed. Copyright © 2016 Elsevier B.V. All rights reserved.

Multipotent cholinesterase/monoamine oxidase inhibitors for the treatment of Alzheimer's disease: design, synthesis, biochemical evaluation, ADMET, molecular modeling, and QSAR analysis of novel donepezil-pyridyl hybrids.

PubMed

Bautista-Aguilera, Oscar M; Esteban, Gerard; Chioua, Mourad; Nikolic, Katarina; Agbaba, Danica; Moraleda, Ignacio; Iriepa, Isabel; Soriano, Elena; Samadi, Abdelouahid; Unzeta, Mercedes; Marco-Contelles, José

2014-01-01

The design, synthesis, and biochemical evaluation of donepezil-pyridyl hybrids (DPHs) as multipotent cholinesterase (ChE) and monoamine oxidase (MAO) inhibitors for the potential treatment of Alzheimer's disease (AD) is reported. The 3D-quantitative structure-activity relationship study was used to define 3D-pharmacophores for inhibition of MAO A/B, acetylcholinesterase (AChE), and butyrylcholinesterase (BuChE) enzymes and to design DPHs as novel multi-target drug candidates with potential impact in the therapy of AD. DPH14 (Electrophorus electricus AChE [EeAChE]: half maximal inhibitory concentration [IC50] =1.1±0.3 nM; equine butyrylcholinesterase [eqBuChE]: IC50 =600±80 nM) was 318-fold more potent for the inhibition of AChE, and 1.3-fold less potent for the inhibition of BuChE than the reference compound ASS234. DPH14 is a potent human recombinant BuChE (hBuChE) inhibitor, in the same range as DPH12 or DPH16, but 13.1-fold less potent than DPH15 for the inhibition of human recombinant AChE (hAChE). Compared with donepezil, DPH14 is almost equipotent for the inhibition of hAChE, and 8.8-fold more potent for hBuChE. Concerning human monoamine oxidase (hMAO) A inhibition, only DPH9 and 5 proved active, compound DPH9 being the most potent (IC50 [MAO A] =5,700±2,100 nM). For hMAO B, only DPHs 13 and 14 were moderate inhibitors, and compound DPH14 was the most potent (IC50 [MAO B] =3,950±940 nM). Molecular modeling of inhibitor DPH14 within EeAChE showed a binding mode with an extended conformation, interacting simultaneously with both catalytic and peripheral sites of EeAChE thanks to a linker of appropriate length. Absortion, distribution, metabolism, excretion and toxicity analysis showed that structures lacking phenyl-substituent show better druglikeness profiles; in particular, DPHs13-15 showed the most suitable absortion, distribution, metabolism, excretion and toxicity properties. Novel donepezil-pyridyl hybrid DPH14 is a potent, moderately selective hAChE and selective irreversible hMAO B inhibitor which might be considered as a promising compound for further development for the treatment of AD.

Proteomic analysis of adducted butyrylcholinesterase for biomonitoring organophosphorus exposures

PubMed Central

Marsillach, Judit; Hsieh, Edward J.; Richter, Rebecca J.; MacCoss, Michael J.; Furlong, Clement E.

2014-01-01

Organophosphorus (OP) compounds include a broad group of toxic chemicals such as insecticides, chemical warfare agents and antiwear agents. The liver cytochromes P450 bioactivate many OPs to potent inhibitors of serine hydrolases. Cholinesterases were the first OP targets discovered and are the most studied. They are used to monitor human exposures to OP compounds. However, the assay that is currently used has limitations. The mechanism of action of OP compounds is the inhibition of serine hydrolases by covalently modifying their active-site serine. After structural rearrangement, the complex OP inhibitor-enzyme is irreversible and will remain in circulation until the modified enzyme is degraded. Mass spectrometry is a sensitive technology for analyzing protein modifications, such as OP-adducted enzymes. These analyses also provide some information about the nature of the OP adduct. Our aim is to develop high-throughput protocols for monitoring OP exposures using mass spectrometry. PMID:23123252

Isothiocyanates: cholinesterase inhibiting, antioxidant, and anti-inflammatory activity.

PubMed

Burčul, Franko; Generalić Mekinić, Ivana; Radan, Mila; Rollin, Patrick; Blažević, Ivica

2018-12-01

Finding a new type of cholinesterase inhibitor that would overcome the brain availability and pharmacokinetic parameters or hepatotoxic liability has been a focus of investigations dealing with the treatment of Alzheimer's disease. Isothiocyanates have not been previously investigated as potential cholinesterase inhibitors. These compounds can be naturally produced from their glucosinolate precursors, secondary metabolites widely distributed in our daily Brassica vegetables. Among 11 tested compounds, phenyl isothiocyanate and its derivatives showed the most promising inhibitory activity. 2-Methoxyphenyl ITC showed best inhibition on acetylcholinesterase with IC 50 of 0.57 mM, while 3-methoxyphenyl ITC showed the best inhibition on butyrylcholinesterase having 49.2% at 1.14 mM. Assessment of the antioxidant efficacy using different methods led to a similar conclusion. The anti-inflammatory activity was also tested using human COX-2 enzyme, ranking phenyl isothiocyanate, and 3-methoxyphenyl isothiocyanate as most active, with ∼99% inhibition at 50 μM.

The interactions of azure B, a metabolite of methylene blue, with acetylcholinesterase and butyrylcholinesterase

DOE Office of Scientific and Technical Information (OSTI.GOV)

Petzer, Anél, E-mail: 12264954@nwu.ac.za; Harvey, Brian H.; Petzer, Jacobus P.

Methylene blue (MB) is reported to possess diverse pharmacological actions and is attracting increasing attention for the treatment of neurodegenerative disorders such as Alzheimer's disease. Among the pharmacological actions of MB, is the significant inhibition of acetylcholinesterase (AChE) and butyrylcholinesterase (BuChE). These activities may, at least in part, underlie MB's beneficial effects in Alzheimer's disease. MB is metabolized to yield N-demethylated products of which azure B, the monodemethyl metabolite, is the predominant species. Azure B has been shown to be pharmacologically active and also possesses a variety of biological actions. Azure B therefore may contribute to the pharmacological profile ofmore » MB. Based on these considerations, the present study investigates the possibility that azure B may, similar to MB, act as an inhibitor of human AChE and BuChE. The results document that azure B inhibits AChE and BuChE with IC{sub 50} values of 0.486 μM and 1.99 μM, respectively. The results further show that azure B inhibits AChE and BuChE reversibly, and that the modes of inhibition are most likely competitive. Although the AChE and BuChE inhibitory activities of azure B are twofold and fivefold, respectively, less potent than those recorded for MB [IC{sub 50}(AChE) = 0.214 μM; IC{sub 50}(BuChE) = 0.389 μM] under identical conditions, azure B may be a contributor to MB's in vivo activation of the cholinergic system and beneficial effects in Alzheimer's disease. - Highlights: • Methylene blue (MB) is a known inhibitor of AChE and BuChE. • Azure B, the major metabolite of MB, also is an inhibitor of AChE and BuChE. • Azure B may be a contributor to MB's in vivo activation of the cholinergic system. • Azure B may contribute to MB's potential in Alzheimer's disease therapy.« less

Bioelectronic sniffer for nicotine using enzyme inhibition.

PubMed

Mitsubayashi, Kohji; Nakayama, Kazumi; Taniguchi, Midori; Saito, Hirokazu; Otsuka, Kimio; Kudo, Hiroyuki

2006-07-28

A novel bioelectronic sniffer for nicotine in the gas phase was developed with enzyme inhibition principle to butyrylcholinesterase activity. The bioelectronic devices for nicotine in the gas and liquid phases were constructed using a Clark-type dissolved oxygen electrode and a membrane immobilized butyrylcholinesterase and choline oxidase. After the assessment of the sensor performances to choline and butyrylcholine as pre-examinations, the characteristics of the biosensor and bio-sniffer for nicotine were evaluated in the liquid and gas phases, respectively. The sensor signal of the bio-devices with 300 micromol l(-1) of butyrylcholine decreased quickly following application of nicotine and reached to the steady-state current, thus relating the concentration of nicotine in the liquid and gas phases. The biosensor was used to measure nicotine solution from 10 to 300 micromol l(-1). In the gas-phase experiment, the current signal of the bio-sniffer was also found to be linearly to the nicotine concentration over the range of 10.0-1000 ppb including 75.0 ppb as threshold limit value (TLV) by American Conference of Governmental Industrial Hygienists (ACGIH).

Nanosized zeolites as a perspective material for conductometric biosensors creation

NASA Astrophysics Data System (ADS)

Kucherenko, Ivan; Soldatkin, Oleksandr; Kasap, Berna Ozansoy; Kirdeciler, Salih Kaan; Kurc, Burcu Akata; Jaffrezic-Renault, Nicole; Soldatkin, Alexei; Lagarde, Florence; Dzyadevych, Sergei

2015-05-01

In this work, the method of enzyme adsorption on different zeolites and mesoporous silica spheres (MSS) was investigated for the creation of conductometric biosensors. The conductometric transducers consisted of gold interdigitated electrodes were placed on the ceramic support. The transducers were modified with zeolites and MSS, and then the enzymes were adsorbed on the transducer surface. Different methods of zeolite attachment to the transducer surface were used; drop coating with heating to 200°C turned out to be the best one. Nanozeolites beta and L, zeolite L, MSS, and silicalite-1 (80 to 450 nm) were tested as the adsorbents for enzyme urease. The biosensors with all tested particles except zeolite L had good analytical characteristics. Silicalite-1 (450 nm) was also used for adsorption of glucose oxidase, acetylcholinesterase, and butyrylcholinesterase. The glucose and acetylcholine biosensors were successfully created, whereas butyrylcholinesterase was not adsorbed on silicalite-1. The enzyme adsorption on zeolites and MSS is simple, quick, well reproducible, does not require use of toxic compounds, and therefore can be recommended for the development of biosensors when these advantages are especially important.

Relationship between serum butyrylcholinesterase and obesity in dogs: a preliminary report.

PubMed

Tvarijonaviciute, Asta; Tecles, Fernando; Ceron, José J

2010-11-01

The aim of this study was to analyse serum butyrylcholinesterase (BChE) values in experimentally developed obesity in Beagle dogs. A short-term fattening protocol was applied to 11 dogs to obtain a wide range of bodyweight (BW) gains and body condition scores (BCS) of 4 and 5; four other dogs with BCS scores of 3 were used as controls. A significant increase in serum BChE activity in overweight dogs was observed when compared with the group of optimal weight dogs. Significant correlation was detected between BChE and BCS (r=0.911), BW (r=0.538) and morphological parameters (waist and thorax circumference, r=0.563 and r=0.552, respectively). Serum BChE concentration had a negative correlation with adiponectin concentration (r=0.719) and a positive correlation with serum lipid profile (cholesterol (r=0.781), HDL-cholesterol (r=0.763), LDL-cholesterol (r=0.878)). It was concluded that serum BChE activity is increased in experimentally overweight dogs and is correlated with other physical and biochemical markers of obesity. Copyright © 2009 Elsevier Ltd. All rights reserved.

Acetylcholinesterase and butyrylcholinesterase inhibitory activity of Pinus species essential oils and their constituents.

PubMed

Bonesi, Marco; Menichini, Federica; Tundis, Rosa; Loizzo, Monica R; Conforti, Filomena; Passalacqua, Nicodemo G; Statti, Giancarlo A; Menichini, Francesco

2010-10-01

This study aimed to investigate the acetylcholinesterase (AChE) and butyrylcholinesterase (BChE) inhibitory activity of the essential oils from Pinus nigra subsp. nigra, P. nigra var. calabrica, and P. heldreichii subsp. leucodermis. This activity is relevant to the treatment of Alzheimer's disease (AD), since cholinesterase drugs are currently the only drugs available to treat AD. P. heldreichii subsp. leucodermis exhibited the most promising activity, with IC(50) values of 51.1 and 80.6 microg/mL against AChE and BChE, respectively. An interesting activity against AChE was also observed with P. nigra subsp. nigra essential oil, with an IC(50) value of 94.4 microg/mL. Essential oils were analyzed by GC and GC-MS with the purpose of investigating their relationships with the observed activities. Among the identified constituents, terpinolene, beta-phellandrene, linalyl acetate, trans-caryophyllene, and terpinen-4-ol were tested. trans-Caryophyllene and terpinen-4-ol inhibited BChE with IC(50) values of 78.6 and 107.6 microg/mL, respectively. beta-Phellandrene was selective against AChE (IC(50) value of 120.2 microg/mL).

Conjugates of γ-Carbolines and Phenothiazine as new selective inhibitors of butyrylcholinesterase and blockers of NMDA receptors for Alzheimer Disease.

PubMed

Makhaeva, Galina F; Lushchekina, Sofya V; Boltneva, Natalia P; Sokolov, Vladimir B; Grigoriev, Vladimir V; Serebryakova, Olga G; Vikhareva, Ekaterina A; Aksinenko, Alexey Yu; Barreto, George E; Aliev, Gjumrakch; Bachurin, Sergey O

2015-08-18

Alzheimer disease is a multifactorial pathology and the development of new multitarget neuroprotective drugs is promising and attractive. We synthesized a group of original compounds, which combine in one molecule γ-carboline fragment of dimebon and phenothiazine core of methylene blue (MB) linked by 1-oxo- and 2-hydroxypropylene spacers. Inhibitory activity of the conjugates toward acetylcholinesterase (AChE), butyrylcholinesterase (BChE) and structurally close to them carboxylesterase (CaE), as well their binding to NMDA-receptors were evaluated in vitro and in silico. These newly synthesized compounds showed significantly higher inhibitory activity toward BChE with IC50 values in submicromolar and micromolar range and exhibited selective inhibitory action against BChE over AChE and CaE. Kinetic studies for the 9 most active compounds indicated that majority of them were mixed-type BChE inhibitors. The main specific protein-ligand interaction is π-π stacking of phenothiazine ring with indole group of Trp82. These compounds emerge as promising safe multitarget ligands for the further development of a therapeutic approach against aging-related neurodegenerative disorders such as Alzheimer and/or other pathological conditions.

Activity of cholinesterases and adenosine deaminase in blood and serum of rats experimentally infected with Trypanosoma cruzi

PubMed Central

DA SILVA, A S; PIMENTEL, V C; FIORENZA, A M; FRANÇA, R T; TONIN, A A; JAQUES, J A; LEAL, C A M; DA SILVA, C B; MORSCH, V; SCHETINGER, M R C; LOPES, S T A; MONTEIRO, S G

2011-01-01

This study aimed to evaluate the activity of cholinesterases and adenosine deaminase (ADA) in blood and serum of rats infected with Trypanosoma cruzi. Twelve adult rats were used in the experiment divided into two uniform groups. Rodents from group A (control group) were non-infected and animals from group B served as infected, receiving intraperitoneally 3.3×107 trypomastigotes/each. Blood collection was performed at days 60 and 120 post-infection (PI) in order to evaluate the hemogram, blood activity of acetylcholinesterase, and serum butyrylcholinesterase and ADA activities. Hematological parameters did not differ between groups. A significant increase (P<0.05) of acetylcholinesterase activity was observed in blood while butyrylcholinesterase had a significant reduction (P<0.01) in serum of infected rats at days 60 and 120 PI. ADA activity in serum showed an inhibition in infected animals when compared to non-infected at day 120 PI. Based on these results, it is possible to conclude that the activity of cholinesterases and ADA were changed in animals infected with T. cruzi. The possible causes of these alterations will be discussed in this paper. PMID:21929880

The distribution of cholinesterases in the cat carotid body.

PubMed

Biscoe, T J; Silver, A

1966-03-01

1. The distribution of acetyl- and butyrylcholinesterase in the carotid body of the cat has been examined histochemically. Studies were made on normal carotid bodies and on carotid bodies from cats in which certain nerves had been cut some time previously. The nerves sectioned were the sinus nerve, the post-ganglionic sympathetic branch of the superior cervical ganglion or the preganglionic cervical sympathetic trunk.2. It was confirmed that more butyrylcholinesterase than acetylcholinesterase is present. Both enzymes are found in three sites: (i) as strands, (ii) as plexuses, (iii) inside a few cells.3. The distribution is unaffected by cutting the sinus nerve or preganglionic cervical sympathetic nerves. Disorganization and depletion of the cholinesterases in the strands and plexuses occurs when the post-ganglionic branch of the superior cervical ganglion is cut. The cholinesterase in cells is unaffected.4. In carotid bodies in which vessels were filled with red blood cells or in which the vascular bed was injected with carmine-gelatine, it was seen that strands and plexuses are associated with blood vessels, and with blood vessels and cells respectively.5. It is suggested that a cholinergic pathway controlling carotid body blood vessels runs in the post-ganglionic cervical sympathetic.

Characterization of cholinesterases in the damselfish Sergeant major (Abudefduf saxatilis).

PubMed

Rodríguez-Fuentes, Gabriela; Soto, Mélina; Luna-Ramírez, Karen

2013-10-01

Cholinesterase (ChE) activity has been used for many years as a biomarker of exposure to organophosphate and carbamate pesticides. Recent studies have demonstrated that there could be biological factors that determine ChE type and levels; thus, juvenile Sergeant major (Abudefduf saxatilis) ChE enzymes were biochemically characterized. ChE enzymes found in the head and trunk were evaluated for their substrate preference and sensitivity to selective inhibitors. The use of the head and trunk was chosen as a strategy to reduce dissection time and to ensure sample uniformity between stations. The results indicated that there are two types of ChE enzymes in the head: acetylcholinesterase (AChE) and atypical butyrylcholinesterase (BChE) that exhibits intermediate characteristics of human AChE and BChE activities. Atypical BChE is predominantly found in the trunk. The results also indicated that the ChE activity found in A. saxatilis may be used as a biomarker in studies monitoring the Mexican Caribbean. Copyright © 2013 Elsevier Inc. All rights reserved.

Microfluidic droplet platform for ultrahigh-throughput single-cell screening of biodiversity.

PubMed

Terekhov, Stanislav S; Smirnov, Ivan V; Stepanova, Anastasiya V; Bobik, Tatyana V; Mokrushina, Yuliana A; Ponomarenko, Natalia A; Belogurov, Alexey A; Rubtsova, Maria P; Kartseva, Olga V; Gomzikova, Marina O; Moskovtsev, Alexey A; Bukatin, Anton S; Dubina, Michael V; Kostryukova, Elena S; Babenko, Vladislav V; Vakhitova, Maria T; Manolov, Alexander I; Malakhova, Maja V; Kornienko, Maria A; Tyakht, Alexander V; Vanyushkina, Anna A; Ilina, Elena N; Masson, Patrick; Gabibov, Alexander G; Altman, Sidney

2017-03-07

Ultrahigh-throughput screening (uHTS) techniques can identify unique functionality from millions of variants. To mimic the natural selection mechanisms that occur by compartmentalization in vivo, we developed a technique based on single-cell encapsulation in droplets of a monodisperse microfluidic double water-in-oil-in-water emulsion (MDE). Biocompatible MDE enables in-droplet cultivation of different living species. The combination of droplet-generating machinery with FACS followed by next-generation sequencing and liquid chromatography-mass spectrometry analysis of the secretomes of encapsulated organisms yielded detailed genotype/phenotype descriptions. This platform was probed with uHTS for biocatalysts anchored to yeast with enrichment close to the theoretically calculated limit and cell-to-cell interactions. MDE-FACS allowed the identification of human butyrylcholinesterase mutants that undergo self-reactivation after inhibition by the organophosphorus agent paraoxon. The versatility of the platform allowed the identification of bacteria, including slow-growing oral microbiota species that suppress the growth of a common pathogen, Staphylococcus aureus , and predicted which genera were associated with inhibitory activity.

Novel structural hybrids of pyrazolobenzothiazines with benzimidazoles as cholinesterase inhibitors.

PubMed

Aslam, Sana; Zaib, Sumera; Ahmad, Matloob; Gardiner, John M; Ahmad, Aqeel; Hameed, Abdul; Furtmann, Norbert; Gütschow, Michael; Bajorath, Jürgen; Iqbal, Jamshed

2014-05-06

Two series of novel pyrazolobenzothiazine-based hybrid compounds were efficiently synthesized starting from saccharin sodium salt. Pyrazolo[4,3-c][1,2]benzothiazine scaffolds were N-arylated by using p-fluorobenzaldehyde, followed by the incorporation of a benzimidazole or similar ring systems by treatment with arylenediamines. These phenylene-connected hybrid compounds were investigated as potential inhibitors of acetylcholinesterase (AChE) and butyrylcholinesterase (BuChE). Compounds 12d and 12k were the most potent AChE inhibitors with IC50 values of 11 and 13 nM, respectively, while 6j (IC50 = 17 nM) proved to be the most active inhibitor against BuChE with remarkable selectivity for BuChE over AChE. Molecular docking studies were also performed on human AChE and BuChE to suggest possible binding modes in which the inhibitor's extended structure is accommodated along the active site gorge of both enzymes. Copyright © 2014 Elsevier Masson SAS. All rights reserved.

Antioxidant Activity, Acetylcholinesterase, and Carbonic Anhydrase Inhibitory Properties of Novel Ureas Derived from Phenethylamines.

PubMed

Aksu, Kadir; Özgeriş, Bünyamin; Taslimi, Parham; Naderi, Ali; Gülçin, İlhami; Göksu, Süleyman

2016-12-01

A series of ureas derived from phenethylamines were synthesized and evaluated for human carbonic anhydrase (hCA) I and II, acetylcholinesterase (AChE), and butyrylcholinesterase (BChE) enzyme inhibitory activities and antioxidant properties. The ureas were synthesized from the reactions of substituted phenethylamines with N,N-dimethylcarbamoyl chloride; then, the synthesized compounds were converted to their corresponding phenolic derivatives via O-demethylation. hCA I and II were effectively inhibited by the newly synthesized compounds, with K i values in the range of 0.307-0.432 nM for hCA I and 0.149-0.278 nM for hCA II. On the other hand, the K i parameters of these compounds for AChE and BChE were determined in the range of 0.129-0.434 and 0.095-0.207 nM, respectively. Phenolic ureas also showed good antioxidant activities. © 2016 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

Selectivity of phenothiazine cholinesterase inhibitors for neurotransmitter systems.

PubMed

Darvesh, Sultan; Macdonald, Ian R; Martin, Earl

2013-07-01

Synthetic derivatives of phenothiazine have been used for over a century as well-tolerated drugs against a variety of human ailments from psychosis to cancer. This implies a considerable diversity in the mechanisms of action produced by structural changes to the phenothiazine scaffold. For example, chlorpromazine treatment of psychosis is related to its interaction with dopaminergic receptors. On the other hand, antagonistic action of such drugs on cholinergic receptor systems would be counter-productive for treatment of Alzheimer's disease. In a search for phenothiazines that are inhibitors of cholinesterases, especially butyrylcholinesterase, with potential to treat Alzheimer's disease, we wished to ascertain that such molecules could be devoid of neurotransmitter receptor interactions. To that end, a number of our synthetic N-10-carbonyl phenothiazine derivatives, with cholinesterase inhibitory activity, were tested for interaction with a variety of neurotransmitter receptor systems. We demonstrate that phenothiazines can be prepared without significant neurotransmitter receptor interactions while retaining high potency as cholinesterase ligands for treatment of Alzheimer's disease. Copyright © 2013 Elsevier Ltd. All rights reserved.

Evidence for the presence of a mammalian-like cholinesterase in Paramecium primaurelia (Protista, Ciliophora) developmental cycle.

PubMed

Delmonte Corrado, M U; Politi, H; Trielli, F; Angelini, C; Falugi, C

1999-01-01

By histochemical and immunohistochemical methods, the presence of cholinergic-like molecules has previously been demonstrated in Paramecium primaurelia, and their functional role in mating-cell pairing was suggested. In this work, both true acetylcholinesterase (AChE) and butyrylcholinesterase (BuChE) activities were electrophoretically investigated, and the presence of molecules immunologically related to BuChE was checked by immunoblotting. The AChE activity, shown in the membrane protein fraction of mating-competent cells and in the cytoplasmic fraction of immature cells, is due to a 260-kDa molecular form, similar to the membrane-bound tetrameric form present in human erythrocytes. This AChE activity does not appear in either the cytoplasmic fraction of mating-competent cells or in the membrane protein fraction of immature cells. No evidence was found for the presence or the activity of BuChE-like molecules. The role of AChE in P. primaurelia developmental cycle is discussed.

Acetylcholinesterase, butyrylcholinesterase and paraoxonase 1 activities in rats treated with cannabis, tramadol or both.

PubMed

Abdel-Salam, Omar M E; Youness, Eman R; Khadrawy, Yasser A; Sleem, Amany A

2016-11-01

To investigate the effect of Cannabis sativa resin and/or tramadol, two commonly drugs of abuse on acetylcholinesterase and butyrylcholinesterase activities as a possible cholinergic biomarkers of neurotoxicity induced by these agents. Rats were treated with cannabis resin (5, 10 or 20 mg/kg) (equivalent to the active constituent Δ 9 -tetrahydrocannabinol), tramadol (5, 10 and 20 mg/kg) or tramadol (10 mg/kg) combined with cannabis resin (5, 10 and 20 mg/kg) subcutaneously daily for 6 weeks. Acetylcholinesterase (AChE) and butyrylcholinesterase (BChE) activities were measured in brain and serum. We also measured the activity of paraoxonase-1 (PON1) in serum of rats treated with these agents. (i) AChE activity in brain increased after 10-20 mg/kg cannabis resin (by 16.3-36.5%). AChE activity in brain did not change after treatment with 5-20 mg/kg tramadol. The administration of both cannabis resin (5, 10 or 20 mg/kg) and tramadol (10 mg/kg) resulted in decreased brain AChE activity by 14.1%, 12.9% and 13.6%, respectively; (ii) BChE activity in serum was markedly and dose-dependently inhibited by cannabis resin (by 60.9-76.9%). BChE activity also decreased by 17.6-36.5% by 10-20 mg/kg tramadol and by 57.2-63.9% by the cannabis resin/tramadol combined treatment; (iii) Cannabis resin at doses of 20 mg/kg increased serum PON1 activity by 25.7%. In contrast, tramadol given at 5, 10 and 20 mg/kg resulted in a dose-dependent decrease in serum PON1 activity by 19%, 36.7%, and 46.1%, respectively. Meanwhile, treatment with cannabis resin plus tramadol resulted in 40.2%, 35.8%, 30.7% inhibition of PON1 activity compared to the saline group. These data suggest that cannabis resin exerts different effects on AChE and BChE activities which could contribute to the memory problems and the decline in cognitive function in chronic users. Copyright © 2016 Hainan Medical University. Production and hosting by Elsevier B.V. All rights reserved.

Selective acetyl- and butyrylcholinesterase inhibitors reduce amyloid-β ex vivo activation of peripheral chemo-cytokines from Alzheimer’s disease subjects: exploring the cholinergic anti-inflammatory pathway

PubMed Central

Reale, Marcella; Di Nicola, Marta; Velluto, Lucia; D’Angelo, Chiara; Costantini, Erica; Lahiri, Debomoy K.; Kamal, Mohammad A.; Yu, Qian-sheng; Greig, Nigel H.

2016-01-01

Increasing evidence suggests that the early pathogenesis of Alzheimer’s disease (AD) is driven by elevated production and/or reduced clearance of amyloid-β peptide (Aβ), which is derived from the larger Aβ precursor protein (APP). Aβ aggregates to form neurotoxic soluble oligomers that trigger a cascade of events leading to neuronal dysfunction, neurodegeneration and, ultimately, clinical dementia. Inflammation, both within the brain and systemically, together with a deficiency in the brain neurotransmitter acetylcholine, which underpinned the development of anticholinesterases for the symptomatic treatment of AD, are invariable hallmarks of the disease. The inter-relation between Aβ, inflammation and cholinergic signaling is complex, with each feeding back onto the others to drive disease progression. To elucidate these interactions plasma samples and peripheral blood mononuclear cells (PBMCs) were evaluated from healthy control (HC) subjects and AD patients. Plasma levels of acetyl- (AChE) and butyrylcholinesterase (BuChE) as well as Aβ were significantly elevated in AD vs. HC subjects, and acetylcholine showed a trend towards reduced levels. Aβ challenge of the AD and HC PBMCs resulted in greater release of inflammatory cytokines interleukin-1β (IL-1β), monocyte chemotactic protein-1 (MCP-1) and tumor necrosis factor-alpha (TNF-α) from AD vs. HC subjects, with IL-10 expression being similarly affected. THP-1 monocytic cells, a cell culture counterpart of PBMCs and brain microglial cells, responded similarly to Aβ as well as to phytohaemagglutinin (PHA) challenge, to allow preliminary analysis of the cellular and molecular pathways that underpin Aβ-induced changes in cytokine expression. In light of prior studies demonstrating that APP expression was regulated by specific cytokines and anticholinesterase drugs, the latter were evaluated on Aβ- and PHA-induced chemo-cytokine expression. Co-incubation with selective inhibitors, such as the acetylcholinesterase (AChE)-inhibitor (−)-phenserine and the butyrylcholinesterase (BuChE)-inhibitor (−)-cymserine analogues mitigated the rise in cytokine levels, and suggest that augmentation of the cholinergic anti-inflammatory pathway may prove valuable in AD. PMID:24359497

A Review of Butyrylcholinesterase as a Therapeutic Target in the Treatment of Alzheimer’s Disease

PubMed Central

Ballard, Clive; Bullock, Roger; Darreh-Shori, Taher; Somogyi, Monique

2013-01-01

Objective: To examine the role of butyrylcholinesterase (BuChE) in cholinergic signaling and neurologic conditions, such as Alzheimer’s disease (AD). The rationale for inhibiting cholinesterases in the management of AD, including clinical evidence supporting use of the dual acetylcholinesterase (AChE) and BuChE inhibitor rivastigmine, is discussed. Data Sources: PubMed searches were performed using butyrylcholinesterase as a keyword. English-language articles referenced in PubMed as of September 2011 were included. Study Selection and Data Synthesis: English-language articles related to BuChE considered to be of clinical relevance to physicians were included. English-language articles specifically related to AChE were not included, as the role of AChE in cholinergic signaling and the underlying pathology of AD is well documented. Reference lists of included publications were used to supplement the search. Results: AChE and BuChE play a role in cholinergic signaling; BuChE can hydrolyze acetylcholine and compensate for AChE when levels are depleted. In the AD brain, AChE levels decrease, while BuChE levels are reportedly increased or unchanged, with changes becoming more pronounced during the disease course. Furthermore, BuChE genotype may influence AD risk and rate of disease progression. Strategies that increase acetylcholine levels (eg, cholinesterase inhibitors) demonstrate symptomatic efficacy in AD. Rivastigmine has proven cognitive efficacy in clinical trials, and data suggest that its action is mediated, in part, by inhibition of BuChE. Retrospective analyses of clinical trials provide evidence that BuChE genotype may also influence treatment response. Conclusions: AChE-selective inhibitors and a dual AChE and BuChE inhibitor demonstrate symptomatic efficacy in AD. Mounting preclinical and clinical evidence for a role of BuChE in maintaining normal cholinergic function and the pathology of AD provides a rationale for further studies investigating use of rivastigmine in AD and the influence of BuChE genotype on observed efficacy. PMID:23930233

Butyrylcholinesterase: K variant, plasma activity, molecular forms and rivastigmine treatment in Alzheimer's disease in a Southern Brazilian population.

PubMed

Bono, G F; Simão-Silva, D P; Batistela, M S; Josviak, N D; Dias, P F R; Nascimento, G A; Souza, R L R; Piovezan, M R; Souza, R K M; Furtado-Alle, L

2015-02-01

Alzheimer's disease (AD) is a neurodegenerative disorder in which there is a decline of cholinergic function. The symptomatic AD treatment involves the use of ChEIs (cholinesterase inhibitors) as rivastigimine, a dual inhibitor. The human butyrylcholinesterase (BChE) is an enzyme that has specific roles in cholinergic neurotransmission and it has been associated with AD. In the serum, BChE is found in four main molecular forms: G1 (monomer); G1-ALB (monomer linked to albumin); G2 (dimer); and G4 (tetramer). The interaction between the products of BCHE gene and CHE2 locus results in CHE2 C5+ and CHE2 C5- phenotypes. CHE2 C5+ phenotype and BChE-K are factors that influence on BChE activity. This work aimed to verify the proportions of BChE molecular forms, total and relative activity in 139 AD patients and 139 elderly controls, taking into account K variant, CHE2 locus, rivastigmine treatment and clinical dementia rating (CDR) of AD patients. Phenotypic frequencies of CHE2 C5+ and frequency of the carriers of the K allele were similar between groups. Total BChE activity in plasma was significantly lower in AD patients than in elderly controls. Furthermore, we found that reduction on plasma BChE activity is associated directly with AD progression in AD patients and that rivastigmine treatment has a stronger effect on BChE activity within the CDR2 group. The reduction in BChE activity did not occur proportionally in all molecular forms. Multiple regression analysis results confirmed that AD acts as the main factor in plasma BChE activity reduction and that severe stages are related with an even greater reduction. These findings suggest that the reduction of total plasma BChE and relative BChE molecular forms activity in AD patients is probably associated with a feedback mechanism and provides a future perspective of using this enzyme as a possible plasmatic secondary marker for AD. Copyright © 2014 Elsevier Ltd. All rights reserved.

Kinetic analysis of butyrylcholinesterase-catalyzed hydrolysis of acetanilides.

PubMed

Masson, Patrick; Froment, Marie-Thérèse; Gillon, Emilie; Nachon, Florian; Darvesh, Sultan; Schopfer, Lawrence M

2007-09-01

The aryl-acylamidase (AAA) activity of butyrylcholinesterase (BuChE) has been known for a long time. However, the kinetic mechanism of aryl-acylamide hydrolysis by BuChE has not been investigated. Therefore, the catalytic properties of human BuChE and its peripheral site mutant (D70G) toward neutral and charged aryl-acylamides were determined. Three neutral (o-nitroacetanilide, m-nitroacetanilide, o-nitrophenyltrifluoroacetamide) and one positively charged (3-(acetamido) N,N,N-trimethylanilinium, ATMA) acetanilides were studied. Hydrolysis of ATMA by wild-type and D70G enzymes showed a long transient phase preceding the steady state. The induction phase was characterized by a hysteretic "burst". This reflects the existence of two enzyme states in slow equilibrium with different catalytic properties. Steady-state parameters for hydrolysis of the three acetanilides were compared to catalytic parameters for hydrolysis of esters giving the same acetyl intermediate. Wild-type BuChE showed substrate activation while D70G displayed a Michaelian behavior with ATMA as with positively charged esters. Owing to the low affinity of BuChE for amide substrates, the hydrolysis kinetics of neutral amides was first order. Acylation was the rate-determining step for hydrolysis of aryl-acetylamide substrates. Slow acylation of the enzyme, relative to that by esters may, in part, be due suboptimal fit of the aryl-acylamides in the active center of BuChE. The hypothesis that AAA and esterase active sites of BuChE are non-identical was tested with mutant BuChE. It was found that mutations on the catalytic serine, S198C and S198D, led to complete loss of both activities. The silent variant (FS117) had neither esterase nor AAA activity. Mutation in the peripheral site (D70G) had the same effect on esterase and AAA activities. Echothiophate inhibited both activities identically. It was concluded that the active sites for esterase and AAA activities are identical, i.e. S198. This excludes any other residue present in the gorge for being the catalytic nucleophile pole.

Phytochemical profile and anticholinesterase and antimicrobial activities of supercritical versus conventional extracts of Satureja montana.

PubMed

Silva, Filipa V M; Martins, Alice; Salta, Joana; Neng, Nuno R; Nogueira, José M F; Mira, Delfina; Gaspar, Natália; Justino, Jorge; Grosso, Clara; Urieta, José S; Palavra, António M S; Rauter, Amélia P

2009-12-23

Winter savory Satureja montana is a medicinal herb used in traditional gastronomy for seasoning meats and salads. This study reports a comparison between conventional (hydrodistillation, HD, and Soxhlet extraction, SE) and alternative (supercritical fluid extraction, SFE) extraction methods to assess the best option to obtain bioactive compounds. Two different types of extracts were tested, the volatile (SFE-90 bar, second separator vs HD) and the nonvolatile fractions (SFE-250 bar, first and second separator vs SE). The inhibitory activity over acetyl- and butyrylcholinesterase by S. montana extracts was assessed as a potential indicator for the control of Alzheimer's disease. The supercritical nonvolatile fractions, which showed the highest content of (+)-catechin, chlorogenic, vanillic, and protocatechuic acids, also inhibited selectively and significantly butyrylcholinesterase, whereas the nonvolatile conventional extract did not affect this enzyme. Microbial susceptibility tests revealed the great potential of S. montana volatile supercritical fluid extract for the growth control and inactivation of Bacillus subtilis and Bacillus cereus, showing some activity against Botrytis spp. and Pyricularia oryzae. Although some studies were carried out on S. montana, the phytochemical analysis together with the biological properties, namely, the anticholinesterase and antimicrobial activities of the plant nonvolatile and volatile supercritical fluid extracts, are described herein for the first time.

Butyrylcholinesterase (BChE) activity is associated with the risk of preeclampsia: influence on lipid and lipoprotein metabolism and oxidative stress.

PubMed

Rahimi, Zohreh; Ahmadi, Reza; Vaisi-Raygani, Asad; Rahimi, Ziba; Bahrehmand, Fariborz; Parsian, Abbas

2013-11-01

To determine the butyrylcholinesterase (BChE) activity and phenotypes in preeclampsia and its possible association with lipid and lipoprotein metabolism and oxidative stress in preeclamptic women. In a case-control study, 101 pregnant women with normal pregnancy and 198 women with preeclampsia from Western Iran were studied. The serum BChE activity and phenotypes were measured using spectrophotometric method. The apolipoprotein E (APOE) genotypes were identified using PCR-RFLP. The serum malondialdehyde (MDA) level and total antioxidant capacity (TAC) were determined by HPLC and commercial kits, respectively. The BChE activity and the frequency of non-usual BChE phenotype in preeclamptic women were significantly lower and higher, respectively compared to controls. There was a higher BChE activity in the presence of APOE ε3ε4 compared to ε3ε3 genotype in preeclamptic women. In addition, there were significant positive correlations between BChE activity and the levels of low-density lipoprotein-cholesterol, high-density lipoprotein-cholesterol, total cholesterol (TC) and TAC. However, there was a negative but significant correlation between BChE activity and MDA level. Our study for the first time indicated that BChE activity might be involved in the pathogenesis of preeclampsia through influence on lipid and lipoprotein metabolism and oxidative stress.

Dual inhibition of acetylcholinesterase and butyrylcholinesterase enzymes by allicin

PubMed Central

Kumar, Suresh

2015-01-01

Objectives: The brain of mammals contains two major form of cholinesterase enzymes, acetylcholinesterase (AChE) and butyrylcholinesterase (BuChE). The dual inhibition of these enzymes is considered as a promising strategy for the treatment of neurological disorder such as Alzheimer's disease (AD), senile dementia, ataxia, and myasthenia gravis. The present study was undertaken to explore the anticholinesterase inhibition property of allicin. Materials and Methods: An assessment of cholinesterase inhibition was carried out by Ellman's assay. Results: The present study demonstrates allicin, a major ingredient of crushed garlic (Allium sativum L.) inhibited both AChE and BuChE enzymes in a concentration-dependent manner. For allicin, the IC50 concentration was 0.01 mg/mL (61.62 μM) for AChE and 0.05 ± 0.018 mg/mL (308.12 μM) for BuChE enzymes. Conclusions: Allicin shows a potential to ameliorate the decline of cognitive function and memory loss associated with AD by inhibiting cholinesterase enzymes and upregulate the levels of acetylcholine (ACh) in the brain. It can be used as a new lead to target AChE and BuChE to upregulate the level of ACh which will be useful in alleviating the symptoms associated with AD. PMID:26288480

The distribution of cholinesterases in the cat carotid body

PubMed Central

Biscoe, T. J.; Silver, Ann

1966-01-01

1. The distribution of acetyl- and butyrylcholinesterase in the carotid body of the cat has been examined histochemically. Studies were made on normal carotid bodies and on carotid bodies from cats in which certain nerves had been cut some time previously. The nerves sectioned were the sinus nerve, the post-ganglionic sympathetic branch of the superior cervical ganglion or the preganglionic cervical sympathetic trunk. 2. It was confirmed that more butyrylcholinesterase than acetylcholinesterase is present. Both enzymes are found in three sites: (i) as strands, (ii) as plexuses, (iii) inside a few cells. 3. The distribution is unaffected by cutting the sinus nerve or preganglionic cervical sympathetic nerves. Disorganization and depletion of the cholinesterases in the strands and plexuses occurs when the post-ganglionic branch of the superior cervical ganglion is cut. The cholinesterase in cells is unaffected. 4. In carotid bodies in which vessels were filled with red blood cells or in which the vascular bed was injected with carmine-gelatine, it was seen that strands and plexuses are associated with blood vessels, and with blood vessels and cells respectively. 5. It is suggested that a cholinergic pathway controlling carotid body blood vessels runs in the post-ganglionic cervical sympathetic. ImagesabcdefPlate 2abcdef PMID:5942823

Genetic variants of serum butyrylcholinesterase in Chilean Mapuche Indians.

PubMed

Acuña, M; Eaton, L; Ramírez, N R; Cifuentes, L; Llop, E

2003-05-01

We estimated the frequencies of serum butyrylcholinesterase (BChE) alleles in three tribes of Mapuche Indians from southern Chile, using enzymatic methods, and we estimated the frequency of allele BCHE*K in one tribe using primer reduced restriction analysis (PCR-PIRA). The three tribes have different degrees of European admixture, which is reflected in the observed frequencies of the atypical allele BCHE*A: 1.11% in Huilliches, 0.89% in Cuncos, and 0% in Pehuenches. This result is evidence in favor of the hypothesis that BCHE*A is absent in native Amerindians. The frequencies of BCHE*F were higher than in most reported studies (3.89%, 5.78%, and 4.41%, respectively). These results are probably due to an overestimation of the frequency of allele BCHE*F, since none of the 20 BCHE UF individuals (by the enzymatic test) individuals analyzed showed either of the two DNA base substitutions associated with this allele. Although enzymatic methods rarely detect the presence of allele BCHE*K, PCR-PIRA found the allele in an appreciable frequency (5.76%), although lower than that found in other ethnic groups. Since observed frequencies of unusual alleles correspond to estimated percentages of European admixture, it is likely that none of these unusual alleles were present in Mapuche Indians before the arrival of Europeans. Copyright 2003 Wiley-Liss, Inc.

Photography by Cameras Integrated in Smartphones as a Tool for Analytical Chemistry Represented by an Butyrylcholinesterase Activity Assay

PubMed Central

Pohanka, Miroslav

2015-01-01

Smartphones are popular devices frequently equipped with sensitive sensors and great computational ability. Despite the widespread availability of smartphones, practical uses in analytical chemistry are limited, though some papers have proposed promising applications. In the present paper, a smartphone is used as a tool for the determination of cholinesterasemia i.e., the determination of a biochemical marker butyrylcholinesterase (BChE). The work should demonstrate suitability of a smartphone-integrated camera for analytical purposes. Paper strips soaked with indoxylacetate were used for the determination of BChE activity, while the standard Ellman’s assay was used as a reference measurement. In the smartphone-based assay, BChE converted indoxylacetate to indigo blue and coloration was photographed using the phone’s integrated camera. A RGB color model was analyzed and color values for the individual color channels were determined. The assay was verified using plasma samples and samples containing pure BChE, and validated using Ellmans’s assay. The smartphone assay was proved to be reliable and applicable for routine diagnoses where BChE serves as a marker (liver function tests; some poisonings, etc.). It can be concluded that the assay is expected to be of practical applicability because of the results’ relevance. PMID:26110404

Photography by Cameras Integrated in Smartphones as a Tool for Analytical Chemistry Represented by an Butyrylcholinesterase Activity Assay.

PubMed

Pohanka, Miroslav

2015-06-11

Smartphones are popular devices frequently equipped with sensitive sensors and great computational ability. Despite the widespread availability of smartphones, practical uses in analytical chemistry are limited, though some papers have proposed promising applications. In the present paper, a smartphone is used as a tool for the determination of cholinesterasemia i.e., the determination of a biochemical marker butyrylcholinesterase (BChE). The work should demonstrate suitability of a smartphone-integrated camera for analytical purposes. Paper strips soaked with indoxylacetate were used for the determination of BChE activity, while the standard Ellman's assay was used as a reference measurement. In the smartphone-based assay, BChE converted indoxylacetate to indigo blue and coloration was photographed using the phone's integrated camera. A RGB color model was analyzed and color values for the individual color channels were determined. The assay was verified using plasma samples and samples containing pure BChE, and validated using Ellmans's assay. The smartphone assay was proved to be reliable and applicable for routine diagnoses where BChE serves as a marker (liver function tests; some poisonings, etc.). It can be concluded that the assay is expected to be of practical applicability because of the results' relevance.

The preparation, in vitro screening and molecular docking of symmetrical bisquaternary cholinesterase inhibitors containing a but-(2E)-en-1,4-diyl connecting linkage.

PubMed

Musilek, Kamil; Pavlikova, Ruzena; Marek, Jan; Komloova, Marketa; Holas, Ondrej; Hrabinova, Martina; Pohanka, Miroslav; Dohnal, Vlastimil; Dolezal, Martin; Gunn-Moore, Frank; Kuca, Kamil

2011-04-01

Carbamate inhibitors (e.g. pyridostigmine bromide) are used as a pre-treatment for the prevention of organophosphorus poisoning. They work by blocking the native function of acetylcholinesterases (AChE) and thus protect AChE against irreversible inhibition by organophosphorus compounds. However, carbamate inhibitors are known for their many undesirable side effects related to the carbamylation of AChE. In this paper, we describe 17 novel bisquaternary compounds and have analysed their effect on AChE inhibition. The newly prepared compounds were evaluated in vitro using both human erythrocyte AChE and human plasmatic butyrylcholinesterase. Their inhibitory ability was expressed as the half maximal inhibitory concentration (IC₅₀) and then compared to the standard carbamate drugs and two AChE reactivators. One of these novel compounds showed promising AChE inhibition in vitro (nM range) and was better than the currently used standards. Additionally, a kinetic assay confirmed the non-competitive inhibition of hAChE by this novel compound. Consequently, the docking results confirmed the apparent π-π or π-cationic interactions with the key amino acid residues of hAChE and the binding of the chosen compound at the enzyme catalytic site.

International Meeting on Cholinesterases (5th) Held in Madras, India on 24-28 September, 1994.

DTIC Science & Technology

1994-09-01

AChE activity . 67 Session F: Structure-Function Relationship of Anticholinesterase Agents: Pesticides and Therapeutic Agents; Noncholinergic Function... plants . The activity of two cholinesterases: acetylcholinesterase [E.C. 3.1.1.7] and butyrylcholinesterase [E.C. 3.1.1.81 was found in homogenates from...was tested in vitro. POSTER NO. 27: ACETYLCHOLINESTERASE ACTIVITY IN PLANTS . S. Madhavan and Gautam Sarath. Department of Biochemistry, University of

Cresyl Saligenin Phosphate, an Organophosphorus Toxicant, Makes Covalent Adducts with Histidine, Lysine and Tyrosine Residues of Human Serum Albumin

PubMed Central

Liyasova, Mariya S.; Schopfer, Lawrence M.; Lockridge, Oksana

2012-01-01

CBDP (2-(2-cresyl)-4H-1-3-2-benzodioxaphosphorin-2-oxide) is a toxic organophosphorus compound. It is generated in vivo from tri-ortho-cresyl phosphate (TOCP), a component of jet engine oil and hydraulic fluids. Exposure to TOCP was proven to occur on board aircraft by finding CBDP-derived phospho-butyrylcholinesterase in the blood of passengers. Adducts on BChE however do not explain the toxicity of CBDP. Critical target proteins of CBDP are yet to be identified. Our goal was to facilitate the search for the critical targets of CBDP by determining the range of amino acid residues capable of reacting with CBDP and characterizing the types of adducts formed. We used human albumin as a model protein. Mass spectral analysis of the tryptic digest of CBDP-treated human albumin revealed adducts on His-67, His-146, His-242, His-247, His-338, Tyr-138, Tyr-140, Lys-199, Lys-351, Lys-414, Lys-432, Lys-525. Adducts formed on tyrosine residues were different from those formed on histidines and lysines. Tyrosines were organophosphorylated by CBDP, while histidine and lysine residues were alkylated. This is the first report of an organophosphorus compound with both phosphorylating and alkylating properties. The hydroxybenzyl adduct on histidine is novel. The ability of CBDP to form stable adducts on histidine, tyrosine and lysine allows one to consider new mechanisms of toxicity from TOCP exposure. PMID:22793878

Cresyl saligenin phosphate, an organophosphorus toxicant, makes covalent adducts with histidine, lysine, and tyrosine residues of human serum albumin.

PubMed

Liyasova, Mariya S; Schopfer, Lawrence M; Lockridge, Oksana

2012-08-20

CBDP [2-(2-cresyl)-4H-1-3-2-benzodioxaphosphorin-2-oxide] is a toxic organophosphorus compound. It is generated in vivo from tri-ortho-cresyl phosphate (TOCP), a component of jet engine oil and hydraulic fluids. Exposure to TOCP was proven to occur on board aircraft by finding CBDP-derived phospho-butyrylcholinesterase in the blood of passengers. Adducts on BChE, however, do not explain the toxicity of CBDP. Critical target proteins of CBDP are yet to be identified. Our goal was to facilitate the search for the critical targets of CBDP by determining the range of amino acid residues capable of reacting with CBDP and characterizing the types of adducts formed. We used human albumin as a model protein. Mass spectral analysis of the tryptic digest of CBDP-treated human albumin revealed adducts on His-67, His-146, His-242, His-247, His-338, Tyr-138, Tyr-140, Lys-199, Lys-351, Lys-414, Lys-432, and Lys-525. Adducts formed on tyrosine residues were different from those formed on histidines and lysines. Tyrosines were organophosphorylated by CBDP, while histidine and lysine residues were alkylated. This is the first report of an organophosphorus compound with both phosphorylating and alkylating properties. The o-hydroxybenzyl adduct on histidine is novel. The ability of CBDP to form stable adducts on histidine, tyrosine, and lysine allows one to consider new mechanisms of toxicity from TOCP exposure.

Progress in the development of histamine H3 receptor antagonists/inverse agonists: a patent review (2013-2017).

PubMed

Łażewska, Dorota; Kieć-Kononowicz, Katarzyna

2018-03-01

Since years, ligands blocking histamine H 3 receptor (H 3 R) activity (antagonists/inverse agonists) are interesting targets in the search for new cures for CNS disorders. Intensive works done by academic and pharmaceutical company researchers have led to many potent and selective H 3 R antagonists/inverse agonists. Some of them have reached to clinical trials. Areas covered: Patent applications from January 2013 to September 2017 and the most important topics connected with H 3 R field are analysed. Espacenet, Patentscope, Pubmed, GoogleScholar or Cochrane Library online databases were principially used to collect all the materials. Expert opinion: The research interest in histamine H 3 R field is still high although the number of patent applications has decreased during the past 4 years (around 20 publications). Complexity of histamine H 3 R biology e.g. many isoforms, constitutive activity, heteromerization with other receptors (dopamine D 2 , D 1 , adenosine A 2A ) and pharmacology make not easy realization and evaluation of therapeutic potential of anti-H 3 R ligands. First results from clinical trials have verified potential utility of histamine H 3 R antagonist/inverse agonists in some diseases. However, more studies are necessary for better understanding of an involvement of the histaminergic system in CNS-related disorders and helping more ligands approach to clinical trials and the market. Lists of abbreviations: hAChEI - human acetylcholinesterase inhibitor; hBuChEI - human butyrylcholinesterase inhibitor; hMAO - human monoamine oxidase; MAO - monoamine oxidase.

Novel Triazole-Quinoline Derivatives as Selective Dual Binding Site Acetylcholinesterase Inhibitors.

PubMed

Mantoani, Susimaire P; Chierrito, Talita P C; Vilela, Adriana F L; Cardoso, Carmen L; Martínez, Ana; Carvalho, Ivone

2016-02-05

Alzheimer's disease (AD) is the most prevalent neurodegenerative disorder worldwide. Currently, the only strategy for palliative treatment of AD is to inhibit acetylcholinesterase (AChE) in order to increase the concentration of acetylcholine in the synaptic cleft. Evidence indicates that AChE also interacts with the β-amyloid (Aβ) protein, acting as a chaperone and increasing the number and neurotoxicity of Aβ fibrils. It is known that AChE has two binding sites: the peripheral site, responsible for the interactions with Aβ, and the catalytic site, related with acetylcholine hydrolysis. In this work, we reported the synthesis and biological evaluation of a library of new tacrine-donepezil hybrids, as a potential dual binding site AChE inhibitor, containing a triazole-quinoline system. The synthesis of hybrids was performed in four steps using the click chemistry strategy. These compounds were evaluated as hAChE and hBChE inhibitors, and some derivatives showed IC50 values in the micro-molar range and were remarkably selective towards hAChE. Kinetic assays and molecular modeling studies confirm that these compounds block both catalytic and peripheral AChE sites. These results are quite interesting since the triazole-quinoline system is a new structural scaffold for AChE inhibitors. Furthermore, the synthetic approach is very efficient for the preparation of target compounds, allowing a further fruitful new chemical library optimization.

An evaluation of neonicotinoids' potential to inhibit human cholinesterases: Protein-ligand docking and interaction profiling studies.

PubMed

Teralı, Kerem

2018-06-16

Many so-called neuroactive insecticides target invertebrate neurotransmitter systems, including the cholinergic system. With their relatively low toxicity to vertebrates, neonicotinoids represent a new class of neuroactive insecticides that bind to nicotinic receptors for acetylcholine in the insect central nervous system and result in paralysis and eventual death due to receptor overstimulation. On the understanding that, today, cholinesterase inhibitors are used to obtain the symptomatic relief of Alzheimer disease (AD), the aforementioned direct cholinomimetic action of neonicotinoids could, perhaps, confer anti-AD drug-like attributes to these compounds. It is shown here, using protein-ligand docking and interaction profiling, that neonicotinoids penetrate deep into the active-site gorge of both acetylcholinesterase and butyrylcholinesterase and that they form relatively strong noncovalent bonds with multiple critical residues that normally bind/hydrolyze choline esters. With their gorge-spanning shape and dual-binding specificity, neonicotinoids (first-generation compounds in particular) represent promising leads for the development of reversible, mixed-type cholinesterase inhibitors in the fight against AD. Copyright © 2018 Elsevier Inc. All rights reserved.

Identification and characterization of novel benzil (diphenylethane-1,2-dione) analogues as inhibitors of mammalian carboxylesterases.

PubMed

Wadkins, Randy M; Hyatt, Janice L; Wei, Xin; Yoon, Kyoung Jin P; Wierdl, Monika; Edwards, Carol C; Morton, Christopher L; Obenauer, John C; Damodaran, Komath; Beroza, Paul; Danks, Mary K; Potter, Philip M

2005-04-21

Carboxylesterases (CE) are ubiquitous enzymes responsible for the metabolism of xenobiotics. Because the structural and amino acid homology among esterases of different classes, the identification of selective inhibitors of these proteins has proved problematic. Using Telik's target-related affinity profiling (TRAP) technology, we have identified a class of compounds based on benzil (1,2-diphenylethane-1,2-dione) that are potent CE inhibitors, with K(i) values in the low nanomolar range. Benzil and 30 analogues demonstrated selective inhibition of CEs, with no inhibitory activity toward human acetylcholinesterase or butyrylcholinesterase. Analysis of structurally related compounds indicated that the ethane-1,2-dione moiety was essential for enzyme inhibition and that potency was dependent on the presence of, and substitution within, the benzene ring. 3D-QSAR analyses of these benzil analogues for three different mammalian CEs demonstrated excellent correlations of observed versus predicted K(i) (r(2) > 0.91), with cross-validation coefficients (q(2)) of 0.9. Overall, these results suggest that selective inhibitors of CEs with potential for use in clinical applications can be designed.

The Anticholinergic and Antiglutamatergic Drug Caramiphen Reduces Seizure Duration in Soman-Exposed Rats: Synergism with the Benzodiazepine Diazepam

DTIC Science & Technology

2012-01-01

progress to self-sustained seizures ( status epilepticus , SE) and result in extensive neuropathology as seen in rats (de Araujo Furtado et al., 2009, 2010...physostigmineOP organophosphorus BuChE butyrylcholinesterase ChE cholinesterase SE status epilepticus ATR atropine sulfate 2-PAM 2-pralidoxime NMDA N...L.C., Lichtenstein, S., Yourick, D.L., 2010. Spontaneous recurrent seizures after status epilepticus induced by soman in Sprague-Dawley rats

Serum butyrylcholinesterase and paraoxonase 1 in a canine model of endotoxemia: effects of choline administration.

PubMed

Tvarijonaviciute, Asta; Kocaturk, Meric; Cansev, Mehmet; Tecles, Fernando; Ceron, Jose J; Yilmaz, Zeki

2012-10-01

Butyrylcholinesterase (BChE) and paraoxonase 1 (PON1) are two serum enzymes synthesized by the liver that are related with inflammation. The main objectives of this study were to determine changes in serum BChE and PON1 by using a canine model of endotoxemia, and to evaluate whether choline alters BChE and PON1 activities during inflammation. For this purpose, a total of 20 mongrel dogs were divided into four groups: control, choline (C), lipopolysaccharide (LPS), and LPS+C. Dogs in the control group were injected with 0.9% NaCl (0.2 ml/kg, i.v.). Dogs in C and LPS+C groups received choline chloride (20 mg/kg, i.v., three times with 4 h intervals). Endotoxin was injected (0.02 mg/kg, i.v., once) to the dogs of LPS and LPS+C groups. Statistically significant decreases in BChE and PON1 activities in LPS group were detected 24 and 48 h post injection, respectively. No statistically significant changes in BChE and PON1 activities at different times were detected in control, C, or LPS+C groups. In conclusion, the data obtained in present study revealed a decrease in serum BChE and PON1 activities in dogs during experimentally induced endotoxemia and that choline administration attenuates these changes. Copyright © 2011 Elsevier Ltd. All rights reserved.

Novel 2-pheynlbenzofuran derivatives as selective butyrylcholinesterase inhibitors for Alzheimer's disease.

PubMed

Kumar, Amit; Pintus, Francesca; Di Petrillo, Amalia; Medda, Rosaria; Caria, Paola; Matos, Maria João; Viña, Dolores; Pieroni, Enrico; Delogu, Francesco; Era, Benedetta; Delogu, Giovanna L; Fais, Antonella

2018-03-13

Alzheimer's disease (AD) is a neurodegenerative disorder representing the leading cause of dementia and is affecting nearly 44 million people worldwide. AD is characterized by a progressive decline in acetylcholine levels in the cholinergic systems, which results in severe memory loss and cognitive impairments. Expression levels and activity of butyrylcholinesterase (BChE) enzyme has been noted to increase significantly in the late stages of AD, thus making it a viable drug target. A series of hydroxylated 2-phenylbenzofurans compounds were designed, synthesized and their inhibitory activities toward acetylcholinesterase (AChE) and BChE enzymes were evaluated. Two compounds (15 and 17) displayed higher inhibitory activity towards BChE with IC 50 values of 6.23 μM and 3.57 μM, and a good antioxidant activity with EC 50 values 14.9 μM and 16.7 μM, respectively. The same compounds further exhibited selective inhibitory activity against BChE over AChE. Computational studies were used to compare protein-binding pockets and evaluate the interaction fingerprints of the compound. Molecular simulations showed a conserved protein residue interaction network between the compounds, resulting in similar interaction energy values. Thus, combination of biochemical and computational approaches could represent rational guidelines for further structural modification of these hydroxy-benzofuran derivatives as future drugs for treatment of AD.

Synthesis of new N-benzylpiperidine derivatives as cholinesterase inhibitors with β-amyloid anti-aggregation properties and beneficial effects on memory in vivo.

PubMed

Więckowska, Anna; Więckowski, Krzysztof; Bajda, Marek; Brus, Boris; Sałat, Kinga; Czerwińska, Paulina; Gobec, Stanislav; Filipek, Barbara; Malawska, Barbara

2015-05-15

Due to the complex nature of Alzheimer's disease, multi-target-directed ligand approaches are one of the most promising strategies in the search for effective treatments. Acetylcholinesterase, butyrylcholinesterase and β-amyloid are the predominant biological targets in the search for new anti-Alzheimer's agents. Our aim was to combine both anticholinesterase and β-amyloid anti-aggregation activities in one molecule, and to determine the therapeutic potential in vivo. We designed and synthesized 28 new compounds as derivatives of donepezil that contain the N-benzylpiperidine moiety combined with the phthalimide or indole moieties. Most of these test compounds showed micromolar activities against cholinesterases and aggregation of β-amyloid, combined with positive results in blood-brain barrier permeability assays. The most promising compound 23 (2-(8-(1-(3-chlorobenzyl)piperidin-4-ylamino)octyl)isoindoline-1,3-dione) is an inhibitor of butyrylcholinesterase (IC50=0.72 μM) that has β-amyloid anti-aggregation activity (72.5% inhibition at 10 μM) and can cross the blood-brain barrier. Moreover, in an animal model of memory impairment induced by scopolamine, the activity of 23 was comparable to that of donepezil. The selected compound 23 is an excellent lead structure in the further search for new anti-Alzheimer's agents. Copyright © 2015 Elsevier Ltd. All rights reserved.

Reactivation of Plasma Butyrylcholinesterase by Pralidoxime Chloride in Patients Poisoned by WHO Class II Toxicity Organophosphorus Insecticides

PubMed Central

Eddleston, Michael

2013-01-01

Some clinicians assess the efficacy of pralidoxime in organophosphorus (OP) poisoned patients by measuring reactivation of butyrylcholinesterase (BuChE). However, the degree of BuChE inhibition varies by OP insecticide, and it is unclear how well oximes reactivate BuChE in vivo. We aimed to assess the usefulness of BuChE activity to monitor pralidoxime treatment by studying its reactivation after pralidoxime administration to patients with laboratory-proven World Health Organization (WHO) class II OP insecticide poisoning. Patient data were derived from 2 studies, a cohort study (using a bolus treatment of 1g pralidoxime chloride) and a randomized controlled trial (RCT) (comparing 2g pralidoxime over 20min, followed by an infusion of 0.5g/h, with placebo). Two grams of pralidoxime variably reactivated BuChE in patients poisoned by 2 diethyl OP insecticides, chlorpyrifos and quinalphos; however, unlike acetylcholinesterase reactivation, this reactivation was not sustained. It did not reactivate BuChE inhibited by the dimethyl OPs dimethoate or fenthion. The 1-g dose produced no reactivation. Pralidoxime produced variable reactivation of BuChE in WHO class II OP-poisoned patients according to the pralidoxime dose administered, OP ingested, and individual patient. The use of BuChE assays for monitoring the effect of pralidoxime treatment is unlikely to be clinically useful. PMID:24052565

An improved immobilized enzyme reactor-mass spectrometry-based label free assay for butyrylcholinesterase ligand screening.

PubMed

Vilela, Adriana Ferreira Lopes; Seidl, Cláudia; Lima, Juliana Maria; Cardoso, Carmen Lúcia

2018-05-15

Acetylcholinesterase (AChE) and butyrylcholinesterase (BChE) are key cholinesterase enzymes responsible for the hydrolysis of acetylcholine into choline and acetic acid, an essential process for the restoration of the cholinergic neuron. The loss of cholinergic function in the central nervous system contributes to the cognitive decline associated with advanced age and Alzheimer's disease (AD). Inhibitions assays represent a significant role in the drug discovery process. Herein, we describe an improved label free method to screen and characterize new BChE ligands. The liquid chromatography system uses an immobilized capillary enzyme reactor (ICER) as a low affinity and high selectivity column coupled to a mass spectrometer (MS). The enzyme activity was evaluated by monitoring the choline's precursor ion [M + H] + m/z 104 for a brief period. The method was validated using two known cholinesterase inhibitors tacrine and galanthamine. The IC 50 values were 0.03 ± 0.006 μM and 0.88 ± 0.2 for tacrine and galanthamine respectively, and Ki was 0.11 ± 0.2 for galanthamine. The efficient combination of the huBChE-ICER with sensitive enzymatic assay detection such as MS, improved the reliable, fast identification of new ligands. Moreover, specific direct quantitation of the product contributes to the reduction of false positive and negative results. Copyright © 2018. Published by Elsevier Inc.

Acorenone B: AChE and BChE Inhibitor as a Major Compound of the Essential Oil Distilled from the Ecuadorian Species Niphogeton dissecta (Benth.) J.F. Macbr.

PubMed

Calva, James; Bec, Nicole; Gilardoni, Gianluca; Larroque, Christian; Cartuche, Luis; Bicchi, Carlo; Montesinos, José Vinicio

2017-10-31

This study investigated the chemical composition, physical proprieties, biological activity, and enantiomeric analysis of the essential oil from the aerial parts of Niphogeton dissecta (culantrillo del cerro) from Ecuador, obtained by steam distillation. The qualitative and quantitative analysis of the essential oil was realized by gas chromatographic and spectroscopic techniques (GC-MS and GC-FID). Acorenone B was identified by GC-MS and NMR experiments. The enantiomeric distribution of some constituents has been assessed by enantio-GC through the use of a chiral cyclodextrin-based capillary column. We identified 41 components that accounted for 96.46% of the total analyzed, the major components were acorenone B (41.01%) and (E)-β-ocimene (29.64%). The enantiomeric ratio of (+)/(-)-β-pinene was 86.9:13.1, while the one of (+)/(-)-sabinene was 80.9:19.1. The essential oil showed a weak inhibitory activity, expressed as Minimal Inhibitory Concentration (MIC), against Enterococcus faecalis (MIC 10 mg/mL) and Staphylococcus aureus (MIC 5 mg/mL). Furthermore, it inhibited butyrylcholinesterase with an IC 50 value of 11.5 μg/mL. Pure acorenone B showed inhibitory activity against both acetylcholinesterase and butyrylcholinesterase, with IC 50 values of 40.8 μg/mL and 10.9 μg/mL, respectively.

Acorenone B: AChE and BChE Inhibitor as a Major Compound of the Essential Oil Distilled from the Ecuadorian Species Niphogeton dissecta (Benth.) J.F. Macbr

PubMed Central

Calva, James; Bec, Nicole; Gilardoni, Gianluca; Larroque, Christian; Cartuche, Luis; Bicchi, Carlo; Montesinos, José Vinicio

2017-01-01

This study investigated the chemical composition, physical proprieties, biological activity, and enantiomeric analysis of the essential oil from the aerial parts of Niphogeton dissecta (culantrillo del cerro) from Ecuador, obtained by steam distillation. The qualitative and quantitative analysis of the essential oil was realized by gas chromatographic and spectroscopic techniques (GC-MS and GC-FID). Acorenone B was identified by GC-MS and NMR experiments. The enantiomeric distribution of some constituents has been assessed by enantio-GC through the use of a chiral cyclodextrin-based capillary column. We identified 41 components that accounted for 96.46% of the total analyzed, the major components were acorenone B (41.01%) and (E)-β-ocimene (29.64%). The enantiomeric ratio of (+)/(−)-β-pinene was 86.9:13.1, while the one of (+)/(−)-sabinene was 80.9:19.1. The essential oil showed a weak inhibitory activity, expressed as Minimal Inhibitory Concentration (MIC), against Enterococcus faecalis (MIC 10 mg/mL) and Staphylococcus aureus (MIC 5 mg/mL). Furthermore, it inhibited butyrylcholinesterase with an IC50 value of 11.5 μg/mL. Pure acorenone B showed inhibitory activity against both acetylcholinesterase and butyrylcholinesterase, with IC50 values of 40.8 μg/mL and 10.9 μg/mL, respectively. PMID:29088082

9-Substituted acridine derivatives as acetylcholinesterase and butyrylcholinesterase inhibitors possessing antioxidant activity for Alzheimer's disease treatment.

PubMed

Makhaeva, Galina F; Lushchekina, Sofya V; Boltneva, Natalia P; Serebryakova, Olga G; Rudakova, Elena V; Ustyugov, Alexey A; Bachurin, Sergey O; Shchepochkin, Alexander V; Chupakhin, Oleg N; Charushin, Valery N; Richardson, Rudy J

2017-11-01

We investigated the inhibitory activity of 4 groups of novel acridine derivatives against acetylcholinesterase (AChE), butyrylcholinesterase (BChE) and carboxylesterase (CaE) using the methods of enzyme kinetics and molecular docking. Antioxidant activity of the compounds was determined using the 2,2'-azinobis-(3-ethylbenzothiazoline-6-sulfonic acid) (ABTS + ) radical decolorization assay as their ability to scavenge free radicals. Analysis of the esterase profiles and antiradical activities of the acridine derivatives showed that 9-aryl(heteroaryl)-N-methyl-9,10-dihydroacridines have a high radical-scavenging activity but low potency as AChE and BChE inhibitors, whereas 9-aryl(heteroaryl)-N-methyl-acridinium tetrafluoroborates effectively inhibit cholinesterases but do not exhibit antiradical activity. In contrast, a group of derivatives of 9-heterocyclic amino-N-methyl-9,10-dihydroacridine has been found that combine effective inhibition of AChE and BChE with rather high radical-scavenging activity. The results of molecular docking well explain the observed features in the efficacy, selectivity, and mechanism of cholinesterase inhibition by the acridine derivatives. Thus, in a series of acridine derivatives we have found compounds possessing dual properties of effective and selective cholinesterase inhibition together with free radical scavenging, which makes promising the use of the acridine scaffold to create multifunctional drugs for the therapy of neurodegenerative diseases. Copyright © 2017 Elsevier Ltd. All rights reserved.

Post-exposure therapy with recombinant human BuChE following percutaneous VX challenge in guinea-pigs

PubMed Central

Mumford, Helen; Troyer, John K.

2011-01-01

Poisoning by nerve agents via the percutaneous (p.c.) route is an issue because the slow absorption of agent could result in poisoning which outlasts the protection provided by conventional pharmacological therapy. The bioscavenger approach is based on the concept of binding nerve agent in the bloodstream, thus preventing nerve agent from reaching the target tissues and inhibiting acetylcholinesterase activity. One bioscavenger that has been extensively studied is human butyrylcholinesterase (huBuChE). Protexia® is a pegylated form of recombinant huBuChE. We used a guinea-pig model of p.c. nerve agent poisoning, using an implanted telemetry system to collect physiological data. Guinea-pigs were poisoned with the nerve agent VX (0.74 mg/kg) (~2.5×LD50). Two hours following VX exposure, Protexia (72 mg/kg) or saline control was administered intramuscularly. All guinea-pigs treated with Protexia (n=8) survived, compared to no survivors in a saline-treated control group (n=8). Survival following VX and Protexia treatment was associated with minimal incapacitation and observable signs of poisoning, and the mitigation or prevention of the detrimental physiological changes (e.g. seizure, bradycardia and hypothermia) observed in control animals. The opportunity for post-exposure treatment may have utility in both civilian and military scenarios, and this is a promising indication for the use of a bioscavenger. PMID:21620937

A new method to characterize the kinetics of cholinesterases inhibited by carbamates.

PubMed

Xiao, Qiaoling; Zhou, Huimin; Wei, Hong; Du, Huaqiao; Tan, Wen; Zhan, Yiyi; Pistolozzi, Marco

2017-09-10

The inhibition of cholinesterases (ChEs) by carbamates includes a carbamylation (inhibition) step, in which the drug transfers its carbamate moiety to the active site of the enzyme and a decarbamylation (activity recovery) step, in which the carbamyl group is hydrolyzed from the enzyme. The carbamylation and decarbamylation kinetics decide the extent and the duration of the inhibition, thus the full characterization of candidate carbamate inhibitors requires the measurement of the kinetic constants describing both steps. Carbamylation and decarbamylation rate constants are traditionally measured by two separate set of experiments, thus making the full characterization of candidate inhibitors time-consuming. In this communication we show that by the analysis of the area under the inhibition-time curve of cholinesterases inhibited by carbamates it is possible to calculate the decarbamylation rate constant from the same data traditionally used to characterize only the carbamylation kinetics, therefore it is possible to obtain a full characterization of the inhibition with a single set of experiments. The characterization of the inhibition kinetics of human and dog plasma butyrylcholinesterase and of human acetylcholinesterase by bambuterol and bambuterol monocarbamate enantiomers was used to demonstrate the validity of the approach. The results showed that the proposed method provides reliable estimations of carbamylation and decarbamylation rate constants thus representing a simple and useful approach to reduce the time required for the characterization of carbamate inhibitors. Copyright © 2017 Elsevier B.V. All rights reserved.

Taxodione and Extracts from Salvia austriaca Roots as Human Cholinesterase Inhibitors.

PubMed

Kuźma, Łukasz; Wysokińska, Halina; Sikora, Joanna; Olszewska, Paulina; Mikiciuk-Olasik, Elżbieta; Szymański, Paweł

2016-02-01

Taxodione, an abietane diterpenoid, was isolated from Salvia austriaca transformed roots grown in in vitro conditions. The compound is known to have antibacterial, cytotoxic and anti-tumour properties. This study evaluates the ability of pure taxodione and extracts obtained from the S. austriaca hairy roots and roots from field-grown plants to inhibit human acetylcholinesterase and butyrylcholinesterase. Both extracts were found to have similar actions against acetylcholinesterase. The IC50 for extracts from transformed and untransformed roots were 142.5 and 139.5 µg ml(-1), respectively. The highest activity towards human acetylcholinesterase was demonstrated by taxodione (IC50  = 54.84 µg ml(-1)). With respect to BChE inhibition, the root extracts demonstrated stronger activity (IC50  = 23.6 µg ml(-1): field-grown plants and 41.6 µg ml(-1): transformed roots) than taxodione (IC50  = 195.9 µg ml(-1)). Taxodione showed significant cytotoxicity against A549 cell line (IC50  = 9.1 µg ml(-1)), whereas the activities for the extracts from S. austriaca roots of field-grown plants (IC50  = 75.7 µg ml(-1)) and hairy roots (IC50  = 86.2 µg ml(-1)) were lower. Computer modelling suggests that taxodione should not demonstrate cardiotoxic or genotoxic activity. It also indicates that taxodione should demonstrate very rapid transport from the body with very good blood-brain barrier penetration, but with no cumulative effect on the human body. The obtained results indicate that taxodione is a safe compound and may be used for further investigations in pharmacological activities. Copyright © 2015 John Wiley & Sons, Ltd.

Different glycosylation in acetylcholinesterases from mammalian brain and erythrocytes.

PubMed

Liao, J; Heider, H; Sun, M C; Brodbeck, U

1992-04-01

Acetylcholinesterases (EC 3.1.1.7, AChE) have varying amounts of carbohydrates attached to the core protein. Sequence analysis of the known primary structures gives evidence for several asparagine-linked carbohydrates. From the differences in molecular mass determined on sodium dodecyl sulfate-polyacrylamide gel before and after deglycosylation with N-glycosidase F (EC 3.2.2.18), it is seen that dimeric AChE from red cell membranes is more heavily glycosylated than the tetrameric brain enzyme. Furthermore, dimeric and tetrameric forms of bovine AChE are more heavily glycosylated than the corresponding human enzymes. Monoclonal antibodies 2E6, 1H11, and 2G8 raised against detergent-soluble AChE from electric organs of Torpedo nacline timilei as well as Elec-39 raised against AChE from Electrophorus electricus cross-reacted with AChE from bovine and human brain but not with AChE from erythrocytes. Treatment of the enzyme with N-glycosidase F abolished binding of monoclonal antibodies, suggesting that the epitope, or part of it, consists of N-linked carbohydrates. Analysis of N-acetylglucosamine sugars revealed the presence of N-acetylglucosamine in all forms of cholinesterases investigated, giving evidence for N-linked glycosylation. On the other hand, N-acetylgalactosamine was not found in AChE from human and bovine brain or in butyrylcholinesterase (EC 3.1.1.8) from human serum, indicating that these forms of cholinesterase did not contain O-linked carbohydrates. Despite the notion that within one species, the different forms of AChE arise from one gene by different splicing, our present results show that dimeric erythrocyte and tetrameric brain AChE must undergo different postsynthetic modifications leading to differences in their glycosylation patterns.

Anticholinesterase activity of the fluorescent zoanthid pigment, parazoanthoxanthin A.

PubMed

Sepcić, K; Turk, T; Macek, P

1998-06-01

A synthetic linear tetrazacyclopent(f)azulene compound, parazoanthoxanthin A (m.w. 214.2), strongly fluorescent pigment occurring in zoanthids, was characterized and assayed for anticholinesterase activity. The pigment, emitting fluorescence at lambda(em) 420 nm, was found to be a pure competitive inhibitor of cholinesterases. At pH 8.0, a Ki value of 19 and 26 microM was determined with insect recombinant, and electric eel acetylcholinesterase. Horse serum butyrylcholinesterase was less sensitive with a Ki of 70 microM.

Reaction of cresyl saligenin phosphate, the organophosphorus agent implicated in aerotoxic syndrome, with human cholinesterases: mechanistic studies employing kinetics, mass spectrometry, and X-ray structure analysis.

PubMed

Carletti, Eugénie; Schopfer, Lawrence M; Colletier, Jacques-Philippe; Froment, Marie-Thérèse; Nachon, Florian; Weik, Martin; Lockridge, Oksana; Masson, Patrick

2011-06-20

Aerotoxic syndrome is assumed to be caused by exposure to tricresyl phosphate (TCP), an antiwear additive in jet engine lubricants and hydraulic fluid. CBDP (2-(ortho-cresyl)-4H-1,2,3-benzodioxaphosphoran-2-one) is the toxic metabolite of triortho-cresylphosphate, a component of TCP. Human butyrylcholinesterase (BChE; EC 3.1.1.8) and human acetylcholinesterase (AChE; EC 3.1.1.7) are irreversibly inhibited by CBDP. The bimolecular rate constants of inhibition (k(i)), determined under pseudo-first-order conditions, displayed a biphasic time course of inhibition with k(i) of 1.6 × 10(8) M(-1) min(-1) and 2.7 × 10(7) M(-1) min(-1) for E and E' forms of BChE. The inhibition constants for AChE were 1 to 2 orders of magnitude slower than those for BChE. CBDP-phosphorylated cholinesterases are nonreactivatable due to ultra fast aging. Mass spectrometry analysis showed an initial BChE adduct with an added mass of 170 Da from cresylphosphate, followed by dealkylation to a structure with an added mass of 80 Da. Mass spectrometry in (18)O-water showed that (18)O was incorporated only during the final aging step to form phospho-serine as the final aged BChE adduct. The crystal structure of CBDP-inhibited BChE confirmed that the phosphate adduct is the ultimate aging product. CBDP is the first organophosphorus agent that leads to a fully dealkylated phospho-serine BChE adduct.

REACTION OF CRESYL SALIGENIN PHOSPHATE, THE ORGANOPHOSPHORUS AGENT IMPLICATED IN THE AEROTOXIC SYNDROME, WITH HUMAN CHOLINESTERASES: MECHANISTIC STUDIES EMPLOYING KINETICS, MASS SPECTROMETRY AND X-RAY STRUCTURE ANALYSIS

PubMed Central

Carletti, Eugénie; Schopfer, Lawrence M.; Colletier, Jacques-Philippe; Froment, Marie-Thérése; Nachon, Florian; Weik, Martin; Lockridge, Oksana; Masson, Patrick

2011-01-01

The aerotoxic syndrome is assumed to be caused by exposure to tricresyl phosphate (TCP), an anti-wear additive in jet engine lubricants and hydraulic fluids. CBDP (2-(ortho-cresyl)-4H-1,2,3-benzodioxaphosphoran-2-one) is the toxic metabolite of tri-ortho-cresylphosphate, a component of TCP. Human butyrylcholinesterase (BChE; EC 3.1.1.8) and human acetylcholinesterase (AChE; EC 3.1.1.7) are irreversibly inhibited by CBDP. The bimolecular rate constants of inhibition (ki), determined under pseudo first-order conditions, displayed a biphasic time course of inhibition with ki 1.6×108 M−1min−1 and 2.7×107 M−1min−1 for E and E′ forms of BChE. The inhibition constants for AChE were one to two orders of magnitude slower than for BChE. CBDP-phosphorylated cholinesterases are non-reactivatable due to ultra fast “aging”. Mass spectrometry analysis showed an initial BChE adduct with an added mass of 170 Da from cresylphosphate, followed by dealkylation to a structure with an added mass of 80 Da. Mass spectrometry in 18O–water showed that 18O was incorporated only during the final aging step to form phospho-serine as the final “aged” BChE adduct. The crystal structure of CBDP-inhibited BChE confirmed that the phosphate adduct is the ultimate aging product. CBDP is the first organophosphorus agent that leads to a fully dealkylated phospho-serine BChE adduct. PMID:21438623

Stoichiometric and catalytic scavengers as protection against nerve agent toxicity: a mini review.

PubMed

Lenz, David E; Yeung, David; Smith, J Richard; Sweeney, Richard E; Lumley, Lucille A; Cerasoli, Douglas M

2007-04-20

Currently fielded treatments for nerve agent intoxication promote survival, but do not afford complete protection against either nerve agent-induced motor and cognitive deficits or neuronal pathology. The use of human plasma-derived butyrylcholinesterase (HuBuChE) to neutralize the toxic effects of nerve agents in vivo has been shown to both aid survival and protect against decreased cognitive function after nerve agent exposure. Recently, a commercially produced recombinant form of human butyrylcholinesterase (r-HuBuChE; PharmAthene Inc.) expressed in the milk of transgenic goats has become available. This material is biochemically similar to plasma-derived HuBuChE in in vitro assays. The pharmacokinetic characteristics of a polyethylene glycol coated (pegylated) form of r-HuBuChE were determined in guinea pigs; the enzyme was rapidly bioavailable with a half-life (t(1/2)) and pharmacokinetic profile that resembled that of plasma-derived huBuChE. Guinea pigs were injected with 140mg/kg (i.m.) of pegylated r-HuBuChE 18h prior to exposure (sc) to 5.5xLD(50) VX or soman. VX and soman were administered in a series of three injections of 1.5xLD(50), 2.0xLD(50), and 2.0xLD(50), respectively, with injections separated by 2h. Pretreatment with pegylated r-HuBuChE provided 100% survival against multiple lethal doses of VX and soman. Guinea pigs displayed no signs of nerve agent toxicity following exposure. Assessments of motor activity, coordination, and acquisition of spatial memory were performed for 2 weeks following nerve agent exposure. There were no measurable decreases in motor or cognitive function during this period. In contrast, animals receiving 1.5xLD(50) challenges of soman or VX and treated with standard atropine, 2-PAM, and diazepam therapy showed 50 and 100% survival, respectively, but exhibited marked decrements in motor function and, in the case of GD, impaired spatial memory acquisition. The advances in this field have resulted in the decision to select both the plasma-derived and the recombinant form of BuChE for advanced development and transition to clinical trials. Efforts have now been expanded to identify a catalytic protein capable of not only binding, but also rapidly hydrolyzing the standard threat nerve agents. Recent work has focused on paraoxonase-1 (PON1), a naturally occurring human serum enzyme with the capacity to catalyze the hydrolysis of nerve agents, albeit too slowly to afford dramatic protection. Using rational design, several amino acids involved in substrate binding have been identified and site-directed mutations have revealed that residue H115 plays an important role in binding. In addition, the stereospecificity of PON1 for the catalytic hydrolysis of soman has been examined. The enzyme exhibits a slight stereospecificity for the C+P+ isomer of soman, which is due more to preferential binding than to selective hydrolysis of this isomer. The results suggest that it may be possible to engineer a mutant form of PON1 with enhanced activity and stereospecificity for the most toxic nerve agent isoforms.

Betaine increases the butyrylcholinesterase activity in rat plasma.

PubMed

Šišková, K; Dubničková, M; Pašková, Ľ; Rajdl, D; Ďuračková, Z; Muchová, J; Pauliková, I; Racek, J

2016-01-01

The physiological function of butyrylcholinesterase (EC 3.1.1.8, BChE) is not clearly understood, but a role was suggested in the fat utilization process, resulting in positive correlation between plasma triglyceride (TG) levels and BChE activity. Consequently we tested the hypothesis that regular intake of betaine, a natural compound intervening in the liver TG metabolism could influence the BChE activity. The BChE activity was estimated spectrophotometrically in plasma of rats fed with betaine enriched standard (B) or high-fat diet (HFB). The results confirmed decreased TG plasma levels after betaine treatment independently on the type of diet (0.15+/-0.03 (B) vs. 0.27+/-0.08 (control) mmol/l; p=0.003 and 0.13+/-0.03 (HFB) vs. 0.27+/-0.08 (control) mmol/l; p=0.005). The BChE activity increased significantly with betaine administration, however the change was more distinct in the HFB group (0.84+/-0.34 (HFB) vs. 0.22+/-0.04 (control) O.D./min/mg; p<0.001 and 0.41+/-0.11 (B) vs. 0.22+/-0.04 (control) O.D./min/mg; p=0.001). In conclusion, betaine intake led to elevated BChE activity in plasma and this effect was potentiated by the HF diet. Since betaine is in general used as a supplement in the treatment of liver diseases accompanied by TG overload, its impact on the BChE activity in the role of the liver function marker should be taken into account.

Pyridine sulfonamide as a small key organic molecule for the potential treatment of type-II diabetes mellitus and Alzheimer's disease: In vitro studies against yeast α-glucosidase, acetylcholinesterase and butyrylcholinesterase.

PubMed

Riaz, Sadaf; Khan, Islam Ullah; Bajda, Marek; Ashraf, Muhammad; Qurat-Ul-Ain; Shaukat, Ayesha; Rehman, Tanzeel Ur; Mutahir, Sadaf; Hussain, Sajjad; Mustafa, Ghulam; Yar, Muhammad

2015-12-01

This paper presents the efficient high yield synthesis of novel pyridine 2,4,6-tricarbohydrazide derivatives (4a-4i) along with their α-glucosidase, acetylcholinesterase (AChE) and butyrylcholinesterase (BChE) inhibition activities. The enzymes inhibition results showed the potential of synthesized compounds in controlling both type-II diabetes mellitus and Alzheimer's disease. In vitro biological investigations revealed that most of compounds were more active against yeast α-glucosidase than the reference compound acarbose (IC50 38.25±0.12μM). Among the tested series the compound 4c bearing 4-flouro benzyl group was noted to be the most active (IC50 25.6±0.2μM) against α-glucosidase, and it displayed weak inhibition activities against AChE and BChE. Compound 4a exhibited the most desired results against all three enzymes, as it was significantly active against all the three enzymes; α-glucosidase (IC50 32.2±0.3μM), AChE (IC50 50.2±0.8μM) and BChE (IC50 43.8±0.8μM). Due to the most favorable activity of 4a against the tested enzymes, for molecular modeling studies this compound was selected to investigate its pattern of interaction with α-glucosidase and AChE targets. Copyright © 2015 Elsevier Inc. All rights reserved.

Evaluating Fmoc-amino acids as selective inhibitors of butyrylcholinesterase

PubMed Central

Gonzalez, Jeannette; Ramirez, Jennifer

2018-01-01

Cholinesterases are involved in neuronal signal transduction, and perturbation of function has been implicated in diseases, such as Alzheimer’s and Huntington’s disease. For the two major classes of cholinesterases, such as acetylcholinesterase (AChE) and butyrylcholinesterase (BChE), previous studies reported BChE activity is elevated in patients with Alzheimer’s disease, while AChE levels remain the same or decrease. Thus, the development of potent and specific inhibitors of BChE have received much attention as a potential therapeutic in the alleviation of neurodegenerative diseases. In this study, we evaluated amino acid analogs as selective inhibitors of BChE. Amino acid analogs bearing a 9-fluorenylmethyloxycarbonyl (Fmoc) group were tested, as the Fmoc group has structural resemblance to previously described inhibitors. We identified leucine, lysine, and tryptophan analogs bearing the Fmoc group as selective inhibitors of BChE. The Fmoc group contributed to inhibition, as analogs bearing a carboxybenzyl group showed ~tenfold higher values for the inhibition constant (KI value). Inclusion of a t-butoxycarbonyl on the side chain of Fmoc tryptophan led to an eightfold lower KI value compared to Fmoc tryptophan alone suggesting that modifications of the amino acid side chains may be designed to create inhibitors with higher affinity. Our results identify Fmoc-amino acids as a scaffold upon which to design BChE-specific inhibitors and provide the foundation for further experimental and computational studies to dissect the interactions that contribute to inhibitor binding. PMID:27522651

Aryl acylamidase activity exhibited by butyrylcholinesterase is higher in chick than in horse, but much lower than in fetal calf serum.

PubMed

Weitnauer, E; Robitzki, A; Layer, P G

1998-10-02

Several side activities have been attributed to butyrylcholinesterase (BChE), including aryl acylamidase (AAA) activity, which is an amidase-like activity with unknown physiological function splitting the artificial substrate o-nitroacetanilide. For avians, extensive developmental data have pointed to neurogenetic functions of BChE, however, a possible AAA activity of BChE has not been studied. In this study, we first compare the relative levels of AAA exhibited by BChE in whole sera from chick, fetal calves (FCS) and horse. Remarkably, FCS exhibits a 400-fold higher ratio of AAA/BChE than horse and 80-fold higher than chick serum. We then show that an immunoisolated preparation of BChE from chicken serum presents significant activity for AAA. Both in sera and with the purified enzyme, the AAA activity is fully inhibited by anticholinesterase drugs, showing that AAA activity is exclusively conveyed by the BChE molecule. Noticeably, AAA inhibition even occurs at lower drug concentrations than that of BChE activity itself. Moreover, AAA is sensitive to serotonin. These data indicate that (1) AAA is a general feature of serum BChE of vertebrates including avians, (2) AAA is effectively inhibited by cholinergic and serotonergic agents, and (3) AAA may have a developmental role, since it is much pronounced in a serum from fetal animals. Functionally, deamination of neuropeptides, a link between cholinergic and serotonergic neurotransmitter systems, and roles in lipoprotein metabolism could be relevant.

Evaluating Fmoc-amino acids as selective inhibitors of butyrylcholinesterase.

PubMed

Gonzalez, Jeannette; Ramirez, Jennifer; Schwans, Jason P

2016-12-01

Cholinesterases are involved in neuronal signal transduction, and perturbation of function has been implicated in diseases, such as Alzheimer's and Huntington's disease. For the two major classes of cholinesterases, such as acetylcholinesterase (AChE) and butyrylcholinesterase (BChE), previous studies reported BChE activity is elevated in patients with Alzheimer's disease, while AChE levels remain the same or decrease. Thus, the development of potent and specific inhibitors of BChE have received much attention as a potential therapeutic in the alleviation of neurodegenerative diseases. In this study, we evaluated amino acid analogs as selective inhibitors of BChE. Amino acid analogs bearing a 9-fluorenylmethyloxycarbonyl (Fmoc) group were tested, as the Fmoc group has structural resemblance to previously described inhibitors. We identified leucine, lysine, and tryptophan analogs bearing the Fmoc group as selective inhibitors of BChE. The Fmoc group contributed to inhibition, as analogs bearing a carboxybenzyl group showed ~tenfold higher values for the inhibition constant (K I value). Inclusion of a t-butoxycarbonyl on the side chain of Fmoc tryptophan led to an eightfold lower K I value compared to Fmoc tryptophan alone suggesting that modifications of the amino acid side chains may be designed to create inhibitors with higher affinity. Our results identify Fmoc-amino acids as a scaffold upon which to design BChE-specific inhibitors and provide the foundation for further experimental and computational studies to dissect the interactions that contribute to inhibitor binding.

Effects of anti-cocaine vaccine and viral gene transfer of cocaine hydrolase in mice on cocaine toxicity including motor strength and liver damage.

PubMed

Gao, Yang; Geng, Liyi; Orson, Frank; Kinsey, Berma; Kosten, Thomas R; Shen, Xiaoyun; Brimijoin, Stephen

2013-03-25

In developing an vivo drug-interception therapy to treat cocaine abuse and hinder relapse into drug seeking provoked by re-encounter with cocaine, two promising agents are: (1) a cocaine hydrolase enzyme (CocH) derived from human butyrylcholinesterase and delivered by gene transfer; (2) an anti-cocaine antibody elicited by vaccination. Recent behavioral experiments showed that antibody and enzyme work in a complementary fashion to reduce cocaine-stimulated locomotor activity in rats and mice. Our present goal was to test protection against liver damage and muscle weakness in mice challenged with massive doses of cocaine at or near the LD50 level (100-120 mg/kg, i.p.). We found that, when the interceptor proteins were combined at doses that were only modestly protective in isolation (enzyme, 1mg/kg; antibody, 8 mg/kg), they provided complete protection of liver tissue and motor function. When the enzyme levels were ~400-fold higher, after in vivo transduction by adeno-associated viral vector, similar protection was observed from CocH alone. Copyright © 2012 Elsevier Ireland Ltd. All rights reserved.

Simultaneous Time-concentration Analysis of Soman and VX Adducts to Butyrylcholinesterase and Albumin by LC-MS-MS.

PubMed

Lee, Jin Young; Kim, Changhwan; Lee, Yong Han

2018-06-01

A sensitive method for the purification and determination of two protein adducts, organophosphorus (OP)-BChE and OP-albumin adducts, in a single sample using a simultaneous sample preparation method was developed and validated using liquid chromatography-tandem mass spectrometry. First, we isolated O-ethyl S-2-diisopropylaminoethyl methyl phosphonothiolate (VX) and O-pinacolyl methylphosphonofluoridate (soman, GD)-BChE adducts using an immunomagnetic separation (IMS) method and the HiTrap™ Blue affinity column was subsequently used to isolate and purify VX and GD-albumin adducts from the plasma of rhesus monkeys exposed to nerve agents. Additionally, we examined the time-concentration profiles of two biomarkers, VX and GD-nonapeptides and VX and GD-tyrosines, derived from OP-BChE and OP-albumin adducts up to 8 weeks after exposure. Based on the results, we determined that VX and GD-tyrosine is more suitable than VX and GD-nonapeptide as a biomarker owing to its longevity. This integrated approach is expected to be applicable for the quantification of other OP-BChE and OP-albumin adducts in human plasma, thus serving as a potential generic assay for exposure to nerve agents.

pH-dependent hydrolysis of acetylcholine: Consequences for non-neuronal acetylcholine.

PubMed

Wessler, Ignaz; Michel-Schmidt, Rosmarie; Kirkpatrick, Charles James

2015-11-01

Acetylcholine is inactivated by acetylcholinesterase and butyrylcholinesterase and thereby its cellular signalling is stopped. One distinguishing difference between the neuronal and non-neuronal cholinergic system is the high expression level of the esterase activity within the former and a considerably lower level within the latter system. Thus, any situation which limits the activity of both esterases will affect the non-neuronal cholinergic system to a much greater extent than the neuronal one. Both esterases are pH-dependent with an optimum at pH above 7, whereas at pH values below 6 particularly the specific acetylcholinesterase is more or less inactive. Thus, acetylcholine is prevented from hydrolysis at such low pH values. The pH of the surface of the human skin is around 5 and therefore non-neuronal acetylcholine released from keratinocytes can be detected in a non-invasive manner. Several clinical conditions like metabolic acidosis, inflammation, fracture-related haematomas, cardiac ischemia and malignant tumours are associated with local or systemic pH values below 7. Thus, the present article describes some consequences of an impaired inactivation of extracellular non-neuronal acetylcholine. Copyright © 2015 Elsevier B.V. All rights reserved.

New insights into the in vitro biological effects, in silico docking and chemical profile of clary sage - Salvia sclarea L.

PubMed

Zengin, Gokhan; Senkardes, Ismail; Mollica, Adriano; Picot-Allain, Carene Marie Nancy; Bulut, Gizem; Dogan, Ahmet; Mahomoodally, M Fawzi

2018-05-06

Salvia sclarea L. is traditionally used to manage common human ailments and is consumed as a food product. This study aimed to establish the phytochemical profile and antioxidant potential of ethyl acetate, methanol, and water extracts of Salvia sclarea. The inhibitory action of the extracts against α-amylase, α-glucosidase, acetylcholinesterase, butyrylcholinesterase, and tyrosinase was also investigated. Methanol extract showed the highest phenolic and flavonoid contents (81.78 mg GAE/g extract and 40.59 mg RE/g extract, respectively). Reversed phase high performance liquid chromatography with diode array detector analysis revealed that S. sclarea was rich in rosmarinic acid. The water extract exhibited the lowest inhibitory activity against α-amylase but the upmost activity against α-glucosidase (0.19 and 18.24 mmol ACAE/g extract, respectively). Experimental data showed that only the water extract (8.86 mg KAE/g extract) significantly inhibited tyrosinase. Docking studies showed that quercetin binds to tyrosinase by two hydrogen and a pi-pi bonds. Salvia sclarea showed interesting biological activity against key enzymes involved in the pathogenesis of common ailments. Copyright © 2018 Elsevier Ltd. All rights reserved.

Characterization of human cytochrome P450s involved in the bioactivation of tri-ortho-cresyl phosphate (ToCP).

PubMed

Reinen, Jelle; Nematollahi, Leyla; Fidder, Alex; Vermeulen, Nico P E; Noort, Daan; Commandeur, Jan N M

2015-04-20

Tri-ortho-cresyl phosphate (ToCP) is a multipurpose organophosphorus compound that is neurotoxic and suspected to be involved in aerotoxic syndrome in humans. It has been reported that not ToCP itself but a metabolite of ToCP, namely, 2-(ortho-cresyl)-4H-1,2,3-benzodioxaphosphoran-2-one (CBDP), may be responsible for this effect as it can irreversibly bind to human butyrylcholinesterase (BuChE) and human acetylcholinesterase (AChE). The bioactivation of ToCP into CBDP involves Cytochrome P450s (P450s). However, the individual human P450s responsible for this bioactivation have not been identified yet. In the present study, we aimed to investigate the metabolism of ToCP by different P450s and to determine the inhibitory effect of the in vitro generated ToCP-metabolites on human BuChE and AChE. Human liver microsomes, rat liver microsomes, and recombinant human P450s were used for that purpose. The recombinant P450s 2B6, 2C18, 2D6, 3A4 and 3A5 showed highest activity of ToCP-bioactivation to BuChE-inhibitory metabolites. Inhibition experiments using pooled human liver microsomes indicated that P450 3A4 and 3A5 were mainly involved in human hepatic bioactivation of ToCP. In addition, these experiments indicated a minor role for P450 1A2. Formation of CBDP by in-house expressed recombinant human P450s 1A2 and 3A4 was proven by both LC-MS and GC-MS analysis. When ToCP was incubated with P450 1A2 and 3A4 in the presence of human BuChE, CBDP-BuChE-adducts were detected by LC-MS/MS which were not present in the corresponding control incubations. These results confirmed the role of human P450s 1A2 and 3A4 in ToCP metabolism and demonstrated that CBDP is the metabolite responsible for the BuChE inactivation. Interindividual differences at the level of P450 1A2 and 3A4 might play an important role in the susceptibility of humans in developing neurotoxic effects, such as aerotoxic syndrome, after exposure to ToCP.

New cholinesterase inhibitors from Garcinia atroviridis.

PubMed

Tan, Wen-Nee; Khairuddean, Melati; Wong, Keng-Chong; Khaw, Kooi-Yeong; Vikneswaran, Murugaiyah

2014-09-01

A triflavanone, Garcineflavanone A (1) and a biflavonol, Garcineflavonol A (2) have been isolated from the stem bark of Garcinia atroviridis (Clusiaceae), collected in Peninsular Malaysia. Their structures were established using one and two-dimensional NMR, UV, IR and mass spectrometry and evaluated in vitro for their acetylcholinesterase (AChE) and butyrylcholinesterase (BChE) enzymes inhibitory activity. Molecular docking studies of the isolated compounds were performed using docking procedure of AutoDock to disclose the binding interaction and orientation of these molecules into the active site gorge. Copyright © 2014 Elsevier B.V. All rights reserved.

The Identification of Butyrylcholinesterase (BCHE) Polymorphisms in a Small Australian Defence Force Cohort

DTIC Science & Technology

2011-01-01

Table D1: Summary of populations and number of individuals Population Approved individual DNA samples Approved Individual cell cultures Yoruba in...P65S Silent phenotype Protein expressed at low levels in culture . Poor activity 1-2% to BZ, BTC, ACT, PTA [11] rs75995351 N/A C373A F71L Unknown...codon at position 129 No protein expressed [8] BCHE*125F A619T L153F Silent phenotype Protein expressed at low levels in culture . Poor activity 1

Preparation and in vitro screening of symmetrical bis-isoquinolinium cholinesterase inhibitors bearing various connecting linkage--implications for early Myasthenia gravis treatment.

PubMed

Musilek, Kamil; Komloova, Marketa; Holas, Ondrej; Hrabinova, Martina; Pohanka, Miroslav; Dohnal, Vlastimil; Nachon, Florian; Dolezal, Martin; Kuca, Kamil

2011-02-01

Inhibitors of acetylcholinesterase are compounds widely used in the treatment of various diseases, such as Alzheimer's disease, glaucoma and Myasthenia gravis (MG). Compounds used in the therapy of MG posses a positive charge in the molecule to ensure peripheral effect of action and minimal blood-brain barrier penetration. The most prescribed carbamate inhibitors are however known for many severe side effects related to the carbamylation of AChE. This paper describes preparation and in vitro evaluation of 20 newly prepared bis-isoquinolinium inhibitors of potential concern for MG. The newly prepared compounds were evaluated in vitro on human recombinant AChE and human plasmatic butyrylcholinesterase (BChE). Their inhibitory ability was expressed as IC50 and compared to chosen standards ambenonium dichloride, edrophonium chloride, BW284c51 and ethopropazine hydrochloride. Three novel compounds presented promising inhibition (in nM range) of both enzymes in vitro better or similar to edrophonium and BW284c51, but worse to ambenonium. The novel inhibitors did not present higher selectivity toward AChE or BChE. The kinetic assay confirmed non-competitive inhibition of hAChE by two selected promising novel compounds. Two newly prepared compounds were also chosen for docking studies that confirmed apparent π-π or π-cationic interactions aside the cholinesterases catalytic sites. The SAR findings were discussed. Copyright © 2010 Elsevier Masson SAS. All rights reserved.

Tetrahydrobenzo[h][1,6]naphthyridine-6-chlorotacrine hybrids as a new family of anti-Alzheimer agents targeting β-amyloid, tau, and cholinesterase pathologies.

PubMed

Di Pietro, Ornella; Pérez-Areales, F Javier; Juárez-Jiménez, Jordi; Espargaró, Alba; Clos, M Victòria; Pérez, Belén; Lavilla, Rodolfo; Sabaté, Raimon; Luque, F Javier; Muñoz-Torrero, Diego

2014-09-12

Optimization of an essentially inactive 3,4-dihydro-2H-pyrano[3,2-c]quinoline carboxylic ester derivative as acetylcholinesterase (AChE) peripheral anionic site (PAS)-binding motif by double O → NH bioisosteric replacement, combined with molecular hybridization with the AChE catalytic anionic site (CAS) inhibitor 6-chlorotacrine and molecular dynamics-driven optimization of the length of the linker has resulted in the development of the trimethylene-linked 1,2,3,4-tetrahydrobenzo[h][1,6]naphthyridine-6-chlorotacrine hybrid 5a as a picomolar inhibitor of human AChE (hAChE). The tetra-, penta-, and octamethylene-linked homologues 5b-d have been also synthesized for comparison purposes, and found to retain the nanomolar hAChE inhibitory potency of the parent 6-chlorotacrine. Further biological profiling of hybrids 5a-d has shown that they are also potent inhibitors of human butyrylcholinesterase and moderately potent Aβ42 and tau anti-aggregating agents, with IC50 values in the submicromolar and low micromolar range, respectively. Also, in vitro studies using an artificial membrane model have predicted a good brain permeability for hybrids 5a-d, and hence, their ability to reach their targets in the central nervous system. The multitarget profile of the novel hybrids makes them promising leads for developing anti-Alzheimer drug candidates with more balanced biological activities. Copyright © 2014 Elsevier Masson SAS. All rights reserved.

Catalytic soman scavenging by Y337A/F338A acetylcholinesterase mutant assisted with novel site-directed aldoximes

PubMed Central

Kovarik, Zrinka; Hrvat, Nikolina Maček; Katalinić, Maja; Sit, Rakesh K.; Paradyse, Alexander; Žunec, Suzana; Musilek, Kamil; Fokin, Valery V.; Taylor, Palmer; Radić, Zoran

2016-01-01

Exposure to the nerve agent soman is difficult to treat due to the rapid dealkylation of soman-acetylcholinesterase (AChE) conjugate known as aging. Oxime antidotes commonly used to reactivate organophosphate inhibited AChE are ineffective against soman, while the efficacy of the recommended nerve agent bioscavenger butyrylcholinesterase is limited by strictly stoichiometric scavenging. To overcome this limitation, we tested ex vivo, in human blood, and in vivo, in soman exposed mice, the capacity of aging-resistant human AChE mutant Y337A/F338A in combination with oxime HI-6 to act as a catalytic bioscavenger of soman. HI-6 was previously shown in vitro to efficiently reactivate this mutant upon soman, as well as VX, cyclosarin, sarin and paraoxon inhibition. We here demonstrate that ex vivo, in whole human blood, 1 μM soman was detoxified within 30 minutes when supplemented with 0.5 μM Y337A/F338A AChE and 100 μM HI-6. This combination was further tested in vivo. Catalytic scavenging of soman in mice improved the therapeutic outcome and resulted in the delayed onset of toxicity symptoms. Furthermore, in a preliminary in vitro screen we identified an even more efficacious oxime than HI-6, in a series of forty-two pyridinium aldoximes, and five imidazole 2-aldoxime N-propyl pyridinium derivatives. One of the later imidazole aldoximes, RS-170B, was a 2–3 –fold more effective reactivator of Y337A/F338A AChE than HI-6 due to the smaller imidazole ring, as indicated by computational molecular models, that affords a more productive angle of nucleophilic attack. PMID:25835984

Efficacy of Recommended Pre-Hospital Human Equivalent Doses of Atropine and Pralidoxime against the Toxic Effects of Carbamate Poisoning in the Hartley Guinea Pig

PubMed Central

Brittain, Matthew K.; McGarry, Kevin G.; Moyer, Robert A.; Babin, Michael C.; Jett, David A.; Platoff, Gennady E.; Yeung, David T.

2016-01-01

Purpose Aldicarb and methomyl are carbamate pesticides commonly implicated in human poisonings. The primary toxic mechanism of action for carbamate poisoning is cholinesterase (ChE) inhibition. As such, it is logical to assume that the currently accepted therapies for organophosphate poisoning [muscarinic antagonist atropine and the oxime acetylcholinesterase reactivator pralidoxime chloride (2-PAM Cl),], could afford therapeutic protection. However, oximes have been shown to be contraindicated for poisoning by some carbamates. Methods A protective ratio study was conducted in guinea pigs to evaluate the efficacy of atropine and 2-PAM Cl. ChE activity was determined in both the blood and cerebral cortex.. Results Co-administration of atropine free base (0.4 mg/kg) and 2-PAM Cl (25.7 mg/kg) demonstrated protective ratios of 2 and 3 against aldicarb and methomyl, respectively, relative to saline. The data reported here show that this protection was primarily mediated by the action of atropine. The reactivator 2-PAM Cl had neither positive nor negative effects on survival. Both blood acetylcholinesterase (AChE) and butyrylcholinesterase (BChE) activities were significantly reduced at 15 minutes post-challenge but gradually returned to normal within 24 h. Analysis of cerebral cortex showed that BChE, but not AChE, activity was reduced in animals that succumbed prior to 24 h after challenge. Conclusion The results suggest that co-administration of atropine and 2-PAM Cl at the currently recommended human equivalent doses for use in the pre-hospital setting to treat organophosphorus nerve agent and pesticide poisoning would likely also be effective against aldicarb or methomyl poisoning. PMID:27102179

Activity of essential oils and individual components against acetyl- and butyrylcholinesterase.

PubMed

Orhan, Ilkay; Kartal, Murat; Kan, Yüksel; Sener, Bilge

2008-01-01

We have tested acetylcholinesterase (AChE) and butyrylcholinesterase (BChE) inhibitory activities of nineteen essential oils obtained from cultivated plants, namely one from Anethum graveolens L. (organic fertilizer), two from Foeniculum vulgare Mill. collected at fully-mature and flowering stages (organic fertilizer), two from Melissa officinalis L. (cultivated using organic and chemical fertilizers), two from Mentha piperita L. and M. spicata L. (organic fertilizer), two from Lavandula officinalis Chaix ex Villars (cultivated using organic and chemical fertilizers), two from Ocimum basilicum L. (green and purple-leaf varieties cultivated using only organic fertilizer), four from Origanum onites L., O. vulgare L., O. munitiflorum Hausskn., and O. majorana L. (cultivated using organic fertilizer), two from Salvia sclarea L. (organic and chemical fertilizers), one from S. officinalis L. (organic fertilizer), and one from Satureja cuneifolia Ten. (organic fertilizer) by a spectrophotometric method of Ellman using ELISA microplate-reader at 1 mg/ml concentration. In addition, a number of single components widely encountered in most of the essential oils [gamma-terpinene, 4-allyl anisole, (-)-carvone, dihydrocarvone, (-)-phencone, cuminyl alcohol, cumol, 4-isopropyl benzaldehyde, trans-anethole, camphene, iso-borneol, (-)-borneol, L-bornyl acetate, 2-decanol, 2-heptanol, methyl-heptanol, farnesol, nerol, iso-pulegol, 1,8-cineole, citral, citronellal, citronellol, geraniol, linalool, alpha-pinene, beta-pinene, piperitone, iso-menthone, menthofurane, linalyl oxide, linalyl ester, geranyl ester, carvacrol, thymol, menthol, vanilline, and eugenol] was also screened for the same activity in the same manner. Almost all of the essential oils showed a very high inhibitory activity (over 80%) against both enzymes, whereas the single components were not as active as the essential oils.

Comparison of the Inhibition of Monoamine Oxidase and Butyrylcholinesterase Activities by Infusions from Green Tea and Some Citrus Peels

PubMed Central

Ademosun, Ayokunle O.

2014-01-01

This study sought to investigate the effect of infusions from green tea (Camellia sinensis) and some citrus peels [shaddock (Citrus maxima), grapefruit (Citrus paradisi), and orange (Citrus sinensis)] on key enzymes relevant to the management of neurodegenerative conditions [monoamine oxidase (MAO) and butyrylcholinesterase (BChE)]. The total phenol contents and antioxidant activities as typified by their 2,2′-azino-bis(3-ethylbenzthiazoline-6-sulphonic acid) (ABTS) radicals scavenging abilities, ferric reducing antioxidant properties, and Fe2+ chelating abilities were also investigated. Green tea had the highest total phenol (43.3 mg/g) and total flavonoid (16.4 mg/g) contents, when compared to orange [total phenol (19.6 mg/g), total flavonoid (6.5 mg/g)], shaddock [total phenol (16.3 mg/g), total flavonoid (5.2 mg/g)], and grapefruit [total phenol (17.7 mg/g), total flavonoid (5.9 mg/g)]. Orange (EC50 = 1.78 mg/mL) had the highest MAO inhibitory ability, while green tea had the least MAO inhibitory ability (EC50 = 2.56 mg/mL). Similarly, green tea had the least BChE inhibitory ability (EC50 = 5.43 mg/mL) when compared to the citrus peels' infusions. However, green tea infusions had the strongest highest ABTS radical scavenging ability, reducing power, and Fe2+ chelating ability. The inhibition of MAO and BChE activities by the green tea and citrus peels infusions could make them good dietary means for the prevention/management of neurodegenerative conditions. PMID:25243093

Biochemical and genetic analysis of butyrylcholinesterase (BChE) in a family, due to prolonged neuromuscular blockade after the use of succinylcholine

PubMed Central

Garcia, Daniel Fantozzi; Oliveira, Ticiano G.; Molfetta, Greice A.; Garcia, Luiz V.; Ferreira, Cristiane A.; Marques, Adriana A.; Silva, Wilson Araujo

2011-01-01

Butyrylcholinesterase (BChE) is a plasma enzyme that catalyzes the hydrolysis of choline esters, including the muscle-relaxant succinylcholine and mivacurium. Patients who present sustained neuromuscular blockade after using succinylcholine usually carry BChE variants with reduced enzyme activity or an acquired BChE deficiency. We report here the molecular basis of the BCHE gene underlying the slow catabolism of succinylcholine in a patient who underwent endoscopic nasal surgery. We measured the enzyme activity of BChE and extracted genomic DNA in order to study the promoter region and all exons of the BCHE gene of the patient, her parents and siblings. PCR products were sequenced and compared with reference sequences from GenBank. We detected that the patient and one of her brothers have two homozygous mutations: nt1615 GCA > ACA (Ala539Thr), responsible for the K variant, and nt209 GAT > GGT (Asp70Gly), which produces the atypical variant A. Her parents and two of her brothers were found to be heterozygous for the AK allele, and another brother is homozygous for the normal allele. Sequence analysis of exon 1 including 5′UTR showed that the proband and her brother are homozygous for –116GG. The AK/AK genotype is considered the most frequent in hereditary hypocholinesterasemia (44%). This work demonstrates the importance of defining the phenotype and genotype of the BCHE gene in patients who are subjected to neuromuscular block by succinylcholine, because of the risk of prolonged neuromuscular paralysis. PMID:21637541

A novel mutation in the BCHE gene and phenotype identified in a child with low butyrylcholinesterase activity: a case report.

PubMed

Yu, Rentao; Guo, Yanzhi; Dan, Yunjie; Tan, Wenting; Mao, Qing; Deng, Guohong

2018-04-10

Butyrylcholinesterase (BChE), an ester hydrolase produced mainly by the liver, hydrolyzes certain short-acting neuromuscular blocking agents, like succinylcholine and mivacurium that are widely used during anesthesia. Patients with BChE deficiency are possibly in danger of postanesthetic apnea. Hereditary BChE deficiency results from the mutations of BCHE gene located on chromosome 3, 3q26.1-q26.2, between nucleotides 165,490,692-165,555,260. This study describes a novel mutation in a child with BChE deficiency. In general, this child appeared healthy and well-developed with a normal appearance. However, the results of Wechsler Intelligence Scale showed that the full-scale intelligence quotient (FIQ) was 53, classified into the group with the minor defect. The BChE activity was 32.0 U/L, considerably lower than the normal lower limit (reference range: 5000-12,000 U/L). Sanger sequencing showed that there were 2 mutations in the exon 2 of BCHE gene of this child. One is a heterozygous mutation rs764588882 (NM_000055.3: c.401_402insA, p.Asn134Lysfs*23). The other one is a heterozygous mutation (NM_000055.3: c.73A > T, p.Lys25Ter) that has never been reported before. The two mutations lead to a premature stop of transcription. Double heterozygous recessive mutations are the cause of BChE deficiency of this boy in this study, including a novel mutation c.73A > T. Intellectual disability is a new phenotype that is probably associated with this mutation.

Exposure of nonbreeding migratory shorebirds to cholinesterase-inhibiting contaminants in the western hemisphere

USGS Publications Warehouse

Strum, K.M.; Hooper, M.J.; Johnson, K.A.; Lanctot, Richard B.; Zaccagnini, M.E.; Sandercock, B.K.

2010-01-01

Migratory shorebirds frequently forage and roost in agricultural habitats, where they may be exposed to cholinesterase-inhibiting pesticides. Exposure to organophosphorus and carbamate compounds, common anti-cholinesterases, can cause sublethal effects, even death. To evaluate exposure of migratory shorebirds to organophosphorus and carbamates, we sampled birds stopping over during migration in North America and wintering in South America. We compared plasma cholinesterase activities and body masses of individuals captured at sites with no known sources of organophosphorus or carbamates to those captured in agricultural areas where agrochemicals were recommended for control of crop pests. In South America, plasma acetylcholinesterase and butyrylcholinesterase activity in Buff-breasted Sandpipers was lower at agricultural sites than at reference sites, indicating exposure to organophosphorus and carbamates. Results of plasma cholinesterase reactivation assays and foot-wash analyses were inconclusive. A meta-analysis of six species revealed no widespread effect of agricultural chemicals on cholinesterase activity. however, four of six species were negative for acetylcholinesterase and one of six for butyrylcholinesterase, indicating negative effects of pesticides on cholinesterase activity in a subset of shorebirds. Exposure to cholinesterase inhibitors can decrease body mass, but comparisons between treatments and hemispheres suggest that agrochemicals did not affect migratory shorebirds' body mass. Our study, one of the first to estimate of shorebirds' exposure to cholinesterase-inhibiting pesticides, suggests that shorebirds are being exposed to cholinesterase- inhibiting pesticides at specific sites in the winter range but not at migratory stopover sites. future research should examine potential behavioral effects of exposure and identify other potential sitesand levels of exposure. ?? The Cooper Ornithological Society 2010.

[The reversible inhibition of cholinesterases from different biological sources by phosphonium betaines].

PubMed

Zhuzhovskiĭ, Iu G; Kuznetsova, L P; Sochilina, E E; Dmitrieva, E N; Gololobov, Iu G; Bykovskaia, E Iu

1996-01-01

The action of some phosphonium betains on cholinesterases from different biological sources has been studied. It has been shown, that all studied betains are reversible inhibitors of cholinesterase hydrolysis of acetyltiocholine. Inhibiting action of these compounds on acetylcholinesterases is about ten times weaker that of the majority of known phosphonium salts, while their action on butyrylcholinesterases has no peculiarities. There were found certain differences for each betain compounds in their action on cholinesterases from different biological sources. These results may be used for detail classification of cholinesterases and allow to extend knowledge in comparative enzymology.

Ag electrode modified with polyhexamethylene biguanide stabilized silver nanoparticles: a new type of SERS substrates for detection of enzymatically generated thiocholine

NASA Astrophysics Data System (ADS)

Tepanov, A. A.; Nechaeva, N. L.; Prokopkina, T. A.; Kudrinskiy, A. A.; Kurochkin, I. N.; Lisichkin, G. V.

2015-11-01

The detection of thiocholine is one of the most widespread techniques for estimation of the cholinesterase activity - acetylcholinesterase and butyrylcholinesterase. Both cholinesterases can be inhibited by organophosphates and carbamates and accordingly can be considered for estimation of these pollutants in the environment. In the current work, SERS spectroscopy was applied for the thiocholine detection. The Ag electrodes modified with silver nanoparticles stabilized by polyhexamethylene biguanide were for the first time suggested as SERS-substrates for that purpose. Such electrodes can be applicable for SERS detection of submicromolar concentrations of thiocholine.

Simultaneous detection of dual biomarkers from humans exposed to organophosphorus pesticides by combination of immunochromatographic test strip and ellman assay.

PubMed

Yang, Mingming; Zhao, Yuting; Wang, Limin; Paulsen, Michael; Simpson, Christopher D; Liu, Fengquan; Du, Dan; Lin, Yuehe

2018-05-01

A novel sandwich immunoassay based immunochromatographic test strip (ICTS) has been developed for simultaneously measuring both butyrylcholinesterase (BChE) activity and the total amount of BChE (including inhibited and active enzyme) from 70 μLpost-exposure human plasma sample. The principle of this method is based on the BChE monoclonal antibody (MAb) capable of acting as both capture antibody and detection antibody. The BChE MAb which was immobilized on the test line was able to recognize both organophosphorus BChE adducts (OP-BChE) and BChE and provided equal binding affinity, permitting detection of the total enzyme amount in post-exposure human plasma samples. The formed immunocomplexes on the test line can further be excised from the test-strip for subsequent off-line measurement of BChE activity using the Ellman assay. Therefore, dual biomarkers of BChE activity and phosphorylation (OP-BChE) will be obtained simultaneously. The whole sandwich-immunoassay was performed on one ICTS, greatly reducing analytical time. The ICTS sensor showed excellent linear responses for assaying total amount of BChE and active BChE ranging from 0.22 to 3.58nM and 0.22-7.17nM, respectively. Both the signal detection limits are 0.10nM. We validated the practical application of the proposed method to measure 124 human plasma samples from orchard workers and cotton farmers with long-term exposure to organophosphorus pesticides (OPs). The results were in highly agreement with LC/MS/MS which verified our method is extremely accurate. Combining the portability and rapidity of test strip and the compatibility of BChE MAb as both capture antibody and detection antibody, the developed method provides a baseline-free, low-cost and rapid tool for in-field monitoring of OP exposures. Copyright © 2018 Elsevier B.V. All rights reserved.

Manufacturing Economics of Plant-Made Biologics: Case Studies in Therapeutic and Industrial Enzymes

PubMed Central

Tusé, Daniel; McDonald, Karen A.

2014-01-01

Production of recombinant biologics in plants has received considerable attention as an alternative platform to traditional microbial and animal cell culture. Industrially relevant features of plant systems include proper eukaryotic protein processing, inherent safety due to lack of adventitious agents, more facile scalability, faster production (transient systems), and potentially lower costs. Lower manufacturing cost has been widely claimed as an intuitive feature of the platform by the plant-made biologics community, even though cost information resides within a few private companies and studies accurately documenting such an advantage have been lacking. We present two technoeconomic case studies representing plant-made enzymes for diverse applications: human butyrylcholinesterase produced indoors for use as a medical countermeasure and cellulases produced in the field for the conversion of cellulosic biomass into ethanol as a fuel extender. Production economics were modeled based on results reported with the latest-generation expression technologies on Nicotiana host plants. We evaluated process unit operations and calculated bulk active and per-dose or per-unit costs using SuperPro Designer modeling software. Our analyses indicate that substantial cost advantages over alternative platforms can be achieved with plant systems, but these advantages are molecule/product-specific and depend on the relative cost-efficiencies of alternative sources of the same product. PMID:24977145

Manufacturing economics of plant-made biologics: case studies in therapeutic and industrial enzymes.

PubMed

Tusé, Daniel; Tu, Tiffany; McDonald, Karen A

2014-01-01

Production of recombinant biologics in plants has received considerable attention as an alternative platform to traditional microbial and animal cell culture. Industrially relevant features of plant systems include proper eukaryotic protein processing, inherent safety due to lack of adventitious agents, more facile scalability, faster production (transient systems), and potentially lower costs. Lower manufacturing cost has been widely claimed as an intuitive feature of the platform by the plant-made biologics community, even though cost information resides within a few private companies and studies accurately documenting such an advantage have been lacking. We present two technoeconomic case studies representing plant-made enzymes for diverse applications: human butyrylcholinesterase produced indoors for use as a medical countermeasure and cellulases produced in the field for the conversion of cellulosic biomass into ethanol as a fuel extender. Production economics were modeled based on results reported with the latest-generation expression technologies on Nicotiana host plants. We evaluated process unit operations and calculated bulk active and per-dose or per-unit costs using SuperPro Designer modeling software. Our analyses indicate that substantial cost advantages over alternative platforms can be achieved with plant systems, but these advantages are molecule/product-specific and depend on the relative cost-efficiencies of alternative sources of the same product.

Effects of a cocaine hydrolase engineered from human butyrylcholinesterase on metabolic profile of cocaine in rats.

PubMed

Chen, Xiabin; Zheng, Xirong; Zhou, Ziyuan; Zhan, Chang-Guo; Zheng, Fang

2016-11-25

Accelerating cocaine metabolism through enzymatic hydrolysis at cocaine benzoyl ester is recognized as a promising therapeutic approach for cocaine abuse treatment. Our more recently designed A199S/F227A/S287G/A328W/Y332G mutant of human BChE, denoted as cocaine hydrolase-3 (CocH3), has a considerably improved catalytic efficiency against cocaine and has been proven active in blocking cocaine-induced toxicity and physiological effects. In the present study, we have further characterized the effects of CocH3 on the detailed metabolic profile of cocaine in rats administrated intravenously (IV) with 5 mg/kg cocaine, demonstrating that IV administration of 0.15 mg/kg CocH3 dramatically changed the metabolic profile of cocaine. Without CocH3 administration, the dominant cocaine-metabolizing pathway in rats was cocaine methyl ester hydrolysis to benzoylecgonine (BZE). With the CocH3 administration, the dominant cocaine-metabolizing pathway in rats became cocaine benzoyl ester hydrolysis to ecgonine methyl ester (EME), and the other two metabolic pathways (i.e. cocaine methyl ester hydrolysis to BZE and cocaine oxidation to norcocaine) became insignificant. The CocH3-catalyzed cocaine benzoyl ester hydrolysis to EME was so efficient such that the measured maximum blood cocaine concentration (∼38 ng/ml) was significantly lower than the threshold blood cocaine concentration (∼72 ng/ml) required to produce any measurable physiological effects. Copyright © 2016 Elsevier Ireland Ltd. All rights reserved.

Inhibition pathways of the potent organophosphate CBDP with cholinesterases revealed by X-ray crystallographic snapshots and mass spectrometry.

PubMed

Carletti, Eugénie; Colletier, Jacques-Philippe; Schopfer, Lawrence M; Santoni, Gianluca; Masson, Patrick; Lockridge, Oksana; Nachon, Florian; Weik, Martin

2013-02-18

Tri-o-cresyl-phosphate (TOCP) is a common additive in jet engine lubricants and hydraulic fluids suspected to have a role in aerotoxic syndrome in humans. TOCP is metabolized to cresyl saligenin phosphate (CBDP), a potent irreversible inhibitor of butyrylcholinesterase (BChE), a natural bioscavenger present in the bloodstream, and acetylcholinesterase (AChE), the off-switch at cholinergic synapses. Mechanistic details of cholinesterase (ChE) inhibition have, however, remained elusive. Also, the inhibition of AChE by CBDP is unexpected, from a structural standpoint, i.e., considering the narrowness of AChE active site and the bulkiness of CBDP. In the following, we report on kinetic X-ray crystallography experiments that provided 2.7-3.3 Å snapshots of the reaction of CBDP with mouse AChE and human BChE. The series of crystallographic snapshots reveals that AChE and BChE react with the opposite enantiomers and that an induced-fit rearrangement of Phe297 enlarges the active site of AChE upon CBDP binding. Mass spectrometry analysis of aging in either H(2)(16)O or H(2)(18)O furthermore allowed us to identify the inhibition steps, in which water molecules are involved, thus providing insights into the mechanistic details of inhibition. X-ray crystallography and mass spectrometry show the formation of an aged end product formed in both AChE and BChE that cannot be reactivated by current oxime-based therapeutics. Our study thus shows that only prophylactic and symptomatic treatments are viable to counter the inhibition of AChE and BChE by CBDP.

Hydrolysis of acetylthiocoline, o-nitroacetanilide and o-nitrotrifluoroacetanilide by fetal bovine serum acetylcholinesterase.

PubMed

Montenegro, María F; Moral-Naranjo, María T; Muñoz-Delgado, Encarnación; Campoy, Francisco J; Vidal, Cecilio J

2009-04-01

Besides esterase activity, acetylcholinesterase (AChE) and butyrylcholinesterase (BuChE) hydrolyze o-nitroacetanilides through aryl acylamidase activity. We have reported that BuChE tetramers and monomers of human blood plasma differ in o-nitroacetanilide (ONA) hydrolysis. The homology in quaternary structure and folding of subunits in the prevalent BuChE species (G4(H)) of human plasma and AChE forms of fetal bovine serum prompted us to study the esterase and amidase activities of fetal bovine serum AChE. The k(cat)/K(m) values for acetylthiocholine (ATCh), ONA and its trifluoro derivative N-(2-nitrophenyl)-trifluoroacetamide (F-ONA) were 398 x 10(6) M(-1) min(-1), 0.8 x 10(6) M(-1) min(-1), and 17.5 x 10(6) M(-1) min(-1), respectively. The lack of inhibition of amidase activity at high F-ONA concentrations makes it unlikely that there is a role for the peripheral anionic site (PAS) in F-ONA degradation, but the inhibition of ATCh, ONA and F-ONA hydrolysis by the PAS ligand fasciculin-2 points to the transit of o-nitroacetalinides near the PAS on their way to the active site. Sedimentation analysis confirmed substrate hydrolysis by tetrameric 10.9S AChE. As compared with esterase activity, amidase activity was less sensitive to guanidine hydrochloride. This reagent led to the formation of 9.3S tetramers with partially unfolded subunits. Their capacity to hydrolyze ATCh and F-ONA revealed that, despite the conformational change, the active site architecture and functionality of AChE were partially retained.

Pseudocatalytic scavenging of the nerve agent VX with human blood components and the oximes obidoxime and HI-6.

PubMed

Wille, Timo; von der Wellen, Jens; Thiermann, Horst; Worek, Franz

2017-03-01

Despite six decades of extensive research in medical countermeasures against nerve agent poisoning, a broad spectrum acetylcholinesterase (AChE) reactivator is not yet available. One current approach is directed toward synthesizing oximes with high affinity and reactivatability toward butyrylcholinesterase (BChE) in plasma to generate an effective pseudocatalytic scavenger. An interim solution could be the administration of external AChE or BChE from blood products to augment pseudocatalytic scavenging with slower but clinically approved oximes to decrease nerve agent concentrations in the body. We here semiquantitatively investigate the ability of obidoxime and HI-6 to decrease the inhibitory activity of VX with human AChE and BChE from whole blood, erythrocyte membranes, erythrocytes, plasma, clinically available fresh frozen plasma and packed red blood cells. The main findings are that whole blood showed a VX concentration-dependent decrease in inhibitory activity with HI-6 being more potent than obidoxime. Using erythrocytes and erythrocyte membranes again, HI-6 was more potent compared to obidoxime. With freshly prepared plasma, obidoxime and HI-6 showed comparable results for the decrease in VX. The use of the clinically available blood products revealed that packed red blood cells showed similar kinetics as fresh erythrocytes. Fresh frozen plasma resulted in a slower and incomplete decrease in inhibitory plasma compared to freshly prepared plasma. In conclusion, the administration of blood products in combination with available oximes augments pseudocatalytic scavenging and might be useful to decrease the body load of persistent, highly toxic nerve agents.

Gender-related differences in circadian rhythm of rat plasma acetyl- and butyrylcholinesterase: effects of sex hormone withdrawal.

PubMed

Alves-Amaral, Gracielle; Pires-Oliveira, Marcelo; Andrade-Lopes, Ana Luiza; Chiavegatti, Tiago; Godinho, Rosely Oliveira

2010-06-07

The role of acetylcholinesterase (AChE) in the termination of the cholinergic response through acetylcholine (ACh) hydrolysis and the involvement of plasma butyrylcholinesterase (BuChE), mainly of hepatic origin, in the metabolism of xenobiotics with ester bonds is well known. Besides, BuChE has a crucial role in ACh hydrolysis, especially when selective anticholinesterases inhibit AChE. Herein, we analyzed the gender-related differences and the circadian changes of rat plasma cholinesterases. Plasma and liver cholinesterase activities were evaluated in control or 2-30-day castrated adult male and female rats. Plasma and liver AChE activities did not differ between genders and were not influenced by sex hormone deprivation. BuChE plasma activity was 7 times greater in female, reflecting gender differences in liver enzyme expression. Castration increased liver and plasma BuChE activity in male, while reduced it in female, abolishing gender differences in enzyme activity. Interestingly, female AChE and BuChE plasma activities varied throughout the day, reaching values 27% and 42% lower, respectively, between 2 p.m. and 6 p.m. when compared to the morning peaks at 8 a.m. Castration attenuated daily female BuChE oscillation. On the other hand, male plasma enzymes remained constant throughout the day. In summary, our results show that liver and plasma BuChE, but not AChE, expression is influenced by sex hormones, leading to high levels of blood BuChE in females. The fluctuation of female plasma BuChE during the day should be taken into account to adjust the bioavailability and the therapeutic effects of cholinesterase inhibitors used in cholinergic-based conditions such Alzheimer's disease. Copyright (c) 2010 Elsevier Ireland Ltd. All rights reserved.

Rivastigmine: the advantages of dual inhibition of acetylcholinesterase and butyrylcholinesterase and its role in subcortical vascular dementia and Parkinson’s disease dementia

PubMed Central

Kandiah, Nagaendran; Pai, Ming-Chyi; Senanarong, Vorapun; Looi, Irene; Ampil, Encarnita; Park, Kyung Won; Karanam, Ananda Krishna; Christopher, Stephen

2017-01-01

Several studies have demonstrated clinical benefits of sustained cholinesterase inhibition with rivastigmine in Alzheimer’s disease (AD) and Parkinson’s disease dementia (PDD). Unlike donepezil and galantamine that selectively inhibit acetylcholinesterase (AChE; EC 3.1.1.7), rivastigmine is a unique cholinesterase inhibitor with both AChE and butyrylcholinesterase (BuChE; EC 3.1.1.8) inhibitory activity. Rivastigmine is also available as transdermal patch that has been approved by the US Food and Drug Administration for the treatment of mild, moderate, and severe AD as well as mild-to-moderate PDD. In this review, we explore the role of BuChE inhibition in addition to AChE inhibition with rivastigmine in the outcomes of cognition, global function, behavioral symptoms, and activities of daily living. Additionally, we review the evidence supporting the use of dual AChE−BuChE inhibitory activity of rivastigmine as a therapeutic strategy in the treatment of neurological disorders, with a focus on the role of rivastigmine in subcortical dementias such as vascular dementia (VaD) and PDD. Toward this objective, we performed a literature search in PubMed and Ovid with limits to articles published in the English language before June 2016. The available evidence from the literature suggests that the dual inhibition of AChE and BuChE may afford additional therapeutic potential of rivastigmine in subcortical dementias (subcortical VaD and PDD) with benefits on cognition and behavioral symptoms. Rivastigmine was found to specifically benefit executive dysfunction frequently observed in subcortical dementias; however, large randomized clinical studies are warranted to support these observations. PMID:28458525

Butyrylcholinesterase inhibitors ameliorate cognitive dysfunction induced by amyloid-β peptide in mice

PubMed Central

Furukawa-Hibi, Yoko; Alkam, Tursun; Nitta, Atsumi; Matsuyama, Akihiro; Mizoguchi, Hiroyuki; Suzuki, Kazuhiko; Moussaoui, Saliha; Yu, Qian-Sheng; Greig, Nigel H.; Nagai, Taku; Yamada, Kiyofumi

2016-01-01

The cholinesterase inhibitor, rivastigmine, ameliorates cognitive dysfunction and is approved for the treatment of Alzheimer's disease (AD). Rivastigmine is a dual inhibitor of acetylcholinesterase (AChE) and butyrylcholinesterase (BuChE); however, the impact of BuChE inhibition on cognitive dysfunction remains to be determined. We compared the effects of a selective BuChE inhibitor, N1-phenethylnorcymserine (PEC), rivastigmine and donepezil (an AChE-selective inhibitor) on cognitive dysfunction induced by amyloid-β peptide (Aβ1–40) in mice. Five-week-old imprinting control region (ICR) mice were injected intracerebroventricularly (i.c.v.) with either Aβ1–40 or the control peptide Aβ40–1 on Day 0, and their recognition memory was analyzed by a novel object recognition test. Treatment with donepezil (1.0 mg/kg), rivastigmine (0.03, 0.1, 0.3 mg/kg) or PEC (1.0, 3.0 mg/kg) 20 min prior to, or immediately after the acquisition session (Day 4) ameliorated the Aβ1–40 induced memory impairment, indicating a beneficial effect on memory acquisition and consolidation. In contrast, none of the investigated drugs proved effective when administrated before the retention session (Day 5). Repeated daily administration of donepezil, rivastigmine or PEC, on Days 0–3 inclusively, ameliorated the cognitive dysfunction in Aβ1–40 challenged mice. Consistent with the reversal of memory impairments, donepezil, rivastigmine or PEC treatment significantly reduced Aβ1–40 induced tyrosine nitration of hippocampal proteins, a marker of oxidative damage. These results indicate that BuChE inhibition, as well as AChE inhibition, is a viable therapeutic strategy for cognitive dysfunction in AD. PMID:21820013

Progression from Mild Cognitive Impairment to Alzheimer's disease: effects of gender, butyrylcholinesterase genotype and rivastigmine treatment

PubMed Central

Ferris, Steven; Nordberg, Agneta; Soininen, Hilkka; Darreh-Shori, Taher; Lane, Roger

2014-01-01

Objective Evaluate the influence of gender and butyrylcholinesterase (BuChE) genotype on incidence of progression to AD, rate of cognitive and functional decline, and response to rivastigmine treatment in mild cognitive impairment (MCI) subjects. Methods This retrospective exploratory analysis from a 3–4 year, randomized, placebo-controlled study of rivastigmine in MCI subjects included participants who consented to pharmacogenetic testing. Results Of 1018 total patients, 490 (253 [52%] female) were successfully genotyped for BuChE. In subjects receiving placebo, the BuChE wt/wt genotype was associated with a statistically significantly higher rate of progression to AD and functional decline in women, compared with men with the BuChE wt/wt genotype. In subjects with a BuChE-K allele receiving placebo, incidence of progression to AD and rate of functional decline were not significantly different by gender, however cognitive decline was significantly faster in men. Statistically significant benefits of rivastigmine treatment on progression to AD, functional decline, ventricular volume expansion, whole brain atrophy and white matter loss were evident in female BuChE wt/wt. Conclusion Gender appears to differentially influence the type of decline in MCI subjects according to BuChE genotype, with more rapid progression of cognitive decline in male BuChE-K, and more rapid progression to AD and functional decline in female BuChE wt/wt. Cognitive decline in male BuChE-K and functional decline and progression to AD in female BuChE wt/wt were significantly attenuated by rivastigmine. Rivastigmine treatment also significantly reduced ventricular expansion, whole brain atrophy rate and white matter loss in female BuChE wt/wt, suggesting a possible disease-modifying effect. PMID:19617863

The use of chemometrics to study multifunctional indole alkaloids from Psychotria nemorosa (Palicourea comb. nov.). Part II: Indication of peaks related to the inhibition of butyrylcholinesterase and monoamine oxidase-A.

PubMed

Klein-Júnior, Luiz C; Viaene, Johan; Tuenter, Emmy; Salton, Juliana; Gasper, André L; Apers, Sandra; Andries, Jan P M; Pieters, Luc; Henriques, Amélia T; Vander Heyden, Yvan

2016-09-09

Psychotria nemorosa is chemically characterized by indole alkaloids and displays significant inhibitory activity on butyrylcholinesterase (BChE) and monoamine oxidase-A (MAO-A), both enzymes related to neurodegenerative disorders. In the present study, 43 samples of P. nemorosa leaves were extracted and fractionated in accordance to previously optimized methods (see Part I). These fractions were analyzed by means of UPLC-DAD and assayed for their BChE and MAO-A inhibitory potencies. The chromatographic fingerprint data was first aligned using correlation optimized warping and Principal Component Analysis to explore the data structure was performed. Multivariate calibration techniques, namely Partial Least Squares (PLS1), PLS2 and Orthogonal Projections to Latent Structure (O-PLS1), were evaluated for modelling the activities as a function of the fingerprints. Since the best results were obtained with O-PLS1 model (RMSECV=9.3 and 3.3 for BChE and MAO-A, respectively), the regression coefficients of the model were analyzed and plotted relative to the original fingerprints. Four peaks were indicated as multifunctional compounds, with the capacity to impair both BChE and MAO-A activities. In order to confirm these results, a semi-prep HPLC technique was used and a fraction containing the four peaks was purified and evaluated in vitro. It was observed that the fraction exhibited an IC50 of 2.12μgmL(-1) for BChE and 1.07μgmL(-1) for MAO-A. These results reinforce the prediction obtained by O-PLS1 modelling. Copyright © 2016 Elsevier B.V. All rights reserved.

Molecular Modeling on Berberine Derivatives toward BuChE: An Integrated Study with Quantitative Structure-Activity Relationships Models, Molecular Docking, and Molecular Dynamics Simulations.

PubMed

Fang, Jiansong; Pang, Xiaocong; Wu, Ping; Yan, Rong; Gao, Li; Li, Chao; Lian, Wenwen; Wang, Qi; Liu, Ai-lin; Du, Guan-hua

2016-05-01

A dataset of 67 berberine derivatives for the inhibition of butyrylcholinesterase (BuChE) was studied based on the combination of quantitative structure-activity relationships models, molecular docking, and molecular dynamics methods. First, a series of berberine derivatives were reported, and their inhibitory activities toward butyrylcholinesterase (BuChE) were evaluated. By 2D- quantitative structure-activity relationships studies, the best model built by partial least-square had a conventional correlation coefficient of the training set (R(2)) of 0.883, a cross-validation correlation coefficient (Qcv2) of 0.777, and a conventional correlation coefficient of the test set (Rpred2) of 0.775. The model was also confirmed by Y-randomization examination. In addition, the molecular docking and molecular dynamics simulation were performed to better elucidate the inhibitory mechanism of three typical berberine derivatives (berberine, C2, and C55) toward BuChE. The predicted binding free energy results were consistent with the experimental data and showed that the van der Waals energy term (ΔEvdw) difference played the most important role in differentiating the activity among the three inhibitors (berberine, C2, and C55). The developed quantitative structure-activity relationships models provide details on the fine relationship linking structure and activity and offer clues for structural modifications, and the molecular simulation helps to understand the inhibitory mechanism of the three typical inhibitors. In conclusion, the results of this study provide useful clues for new drug design and discovery of BuChE inhibitors from berberine derivatives. © 2015 John Wiley & Sons A/S.

Butyrylcholinesterase regulates central ghrelin signaling and has an impact on food intake and glucose homeostasis.

PubMed

Chen, V P; Gao, Y; Geng, L; Brimijoin, S

2017-09-01

Ghrelin is the only orexigenic hormone known to stimulate food intake and promote obesity and insulin resistance. We recently showed that plasma ghrelin is controlled by butyrylcholinesterase (BChE), which has a strong impact on feeding and weight gain. BChE knockout (KO) mice are prone to obesity on high-fat diet, but hepatic BChE gene transfer rescues normal food intake and obesity resistance. However, these mice lack brain BChE and still develop hyperinsulinemia and insulin resistance, suggesting essential interactions between BChE and ghrelin within the brain. To test the hypothesis we used four experimental groups: (1) untreated wild-type mice, (2) BChE KO mice with LUC delivered by adeno-associated virus (AAV) in combined intravenous (i.v.) and intracerebral (i.c.) injections, (3) KO mice given AAV for mouse BChE (i.v. only) and (4) KO mice given the same vector both i.v. and i.c. All mice ate a 45% calorie high-fat diet from the age of 1 month. Body weight, body composition, daily caloric intake and serum parameters were monitored throughout, and glucose tolerance and insulin tolerance tests were performed at intervals. Circulating ghrelin levels dropped substantially in the KO mice after i.v. AAV-BChE delivery, which led to normal food intake and healthy body weight. BChE KO mice that received AAV-BChE through i.v. and i.c. combined treatments not only resisted weight gain on high-fat diet but also retained normal glucose and insulin tolerance. These data indicate a central role for BChE in regulating both insulin and glucose homeostasis. BChE gene transfer could be a useful therapy for complications linked to diet-induced obesity and insulin resistance.

In Vitro and In Vivo Metabolism and Inhibitory Activities of Vasicine, a Potent Acetylcholinesterase and Butyrylcholinesterase Inhibitor

PubMed Central

Liu, Wei; Shi, Xiaoyuan; Yang, Yadi; Cheng, Xuemei; Liu, Qing; Han, Han; Yang, Baohua; He, Chunyong; Wang, Yongli; Jiang, Bo; Wang, Zhengtao; Wang, Changhong

2015-01-01

Vasicine (VAS), a potential natural cholinesterase inhibitor, exhibited promising anticholinesterase activity in preclinical models and has been in development for treatment of Alzheimer’s disease. This study systematically investigated the in vitro and in vivo metabolism of VAS in rat using ultra performance liquid chromatography combined with electrospray ionization quadrupole time-of-flight mass spectrometry. A total of 72 metabolites were found based on a detailed analysis of their 1H- NMR and 13C NMR data. Six key metabolites were isolated from rat urine and elucidated as vasicinone, vasicinol, vasicinolone, 1,2,3,9-tetrahydropyrrolo [2,1-b] quinazolin-3-yl hydrogen sulfate, 9-oxo-1,2,3,9-tetrahydropyrrolo [2,1-b] quinazolin-3-yl hydrogen sulfate, and 1,2,3,9-tetrahydropyrrolo [2,1-b] quinazolin-3-β-D-glucuronide. The metabolic pathway of VAS in vivo and in vitro mainly involved monohydroxylation, dihydroxylation, trihydroxylation, oxidation, desaturation, sulfation, and glucuronidation. The main metabolic soft spots in the chemical structure of VAS were the 3-hydroxyl group and the C-9 site. All 72 metabolites were found in the urine sample, and 15, 25, 45, 18, and 11 metabolites were identified from rat feces, plasma, bile, rat liver microsomes, and rat primary hepatocyte incubations, respectively. Results indicated that renal clearance was the major excretion pathway of VAS. The acetylcholinesterase (AChE) and butyrylcholinesterase (BChE) inhibitory activities of VAS and its main metabolites were also evaluated. The results indicated that although most metabolites maintained potential inhibitory activity against AChE and BChE, but weaker than that of VAS. VAS undergoes metabolic inactivation process in vivo in respect to cholinesterase inhibitory activity. PMID:25849329

Butyrylcholinesterase K and Apolipoprotein E-ɛ4 Reduce the Age of Onset of Alzheimer's Disease, Accelerate Cognitive Decline, and Modulate Donepezil Response in Mild Cognitively Impaired Subjects.

PubMed

De Beaumont, Louis; Pelleieux, Sandra; Lamarre-Théroux, Louise; Dea, Doris; Poirier, Judes

2016-10-04

Genetic heterogeneity in amnestic mild cognitively impaired (aMCI) subjects could lead to variations in progression rates and response to cholinomimetic agents. Together with the apolipoprotein E4 (APOE-ɛ4) gene, butyrylcholinesterase (BCHE) has become recently one of the few Alzheimer's disease (AD) susceptibility genes with distinct pharmacogenomic properties. To validate candidate genes (APOE/BCHE) which display associations with age of onset of AD and donepezil efficacy in aMCI subjects. Using the Petersen et al. (2005) study on vitamin E and donepezil efficacy in aMCI, we contrasted the effects of BCHE and APOE variants on donepezil drug response using the Alzheimer's Disease Assessment Score-Cognition (ADAS-Cog) scale. Independently, we assessed the effects of APOE/BCHE genotypes on age of onset and cortical choline acetyltransferase activity in autopsy-confirmed AD and age-matched control subjects. Statistical analyses revealed a significant earlier age of onset in AD for APOE-ɛ4, BCHE-K*, and APOE-ɛ4/BCHE-K* carriers. Among the carriers of APOE-ɛ4 and BCHE-K*, the benefit of donepezil was evident at the end of the three-year follow-up. The responder's pharmacogenomic profile is consistent with reduced brain cholinergic activity measured in APOE-ɛ4 and BCHE-K* positive subjects. APOE-ɛ4 and BCHE-K* positive subjects display an earlier age of onset of AD, an accelerated cognitive decline and a greater cognitive benefits to donepezil therapy. These results clearly emphasize the necessity of monitoring potential pharmacogenomic effects in this population of subjects, and suggest enrichment strategies for secondary prevention trials involving prodromal AD subjects.

Rivastigmine: the advantages of dual inhibition of acetylcholinesterase and butyrylcholinesterase and its role in subcortical vascular dementia and Parkinson's disease dementia.

PubMed

Kandiah, Nagaendran; Pai, Ming-Chyi; Senanarong, Vorapun; Looi, Irene; Ampil, Encarnita; Park, Kyung Won; Karanam, Ananda Krishna; Christopher, Stephen

2017-01-01

Several studies have demonstrated clinical benefits of sustained cholinesterase inhibition with rivastigmine in Alzheimer's disease (AD) and Parkinson's disease dementia (PDD). Unlike donepezil and galantamine that selectively inhibit acetylcholinesterase (AChE; EC 3.1.1.7), rivastigmine is a unique cholinesterase inhibitor with both AChE and butyrylcholinesterase (BuChE; EC 3.1.1.8) inhibitory activity. Rivastigmine is also available as transdermal patch that has been approved by the US Food and Drug Administration for the treatment of mild, moderate, and severe AD as well as mild-to-moderate PDD. In this review, we explore the role of BuChE inhibition in addition to AChE inhibition with rivastigmine in the outcomes of cognition, global function, behavioral symptoms, and activities of daily living. Additionally, we review the evidence supporting the use of dual AChE-BuChE inhibitory activity of rivastigmine as a therapeutic strategy in the treatment of neurological disorders, with a focus on the role of rivastigmine in subcortical dementias such as vascular dementia (VaD) and PDD. Toward this objective, we performed a literature search in PubMed and Ovid with limits to articles published in the English language before June 2016. The available evidence from the literature suggests that the dual inhibition of AChE and BuChE may afford additional therapeutic potential of rivastigmine in subcortical dementias (subcortical VaD and PDD) with benefits on cognition and behavioral symptoms. Rivastigmine was found to specifically benefit executive dysfunction frequently observed in subcortical dementias; however, large randomized clinical studies are warranted to support these observations.

Quantification of Butyrylcholinesterase Activity as a Sensitive and Specific Biomarker of Alzheimer's Disease.

PubMed

Macdonald, Ian R; Maxwell, Selena P; Reid, George A; Cash, Meghan K; DeBay, Drew R; Darvesh, Sultan

2017-01-01

Amyloid-β (Aβ) plaques are a neuropathological hallmark of Alzheimer's disease (AD); however, a significant number of cognitively normal older adults can also have Aβ plaques. Thus, distinguishing AD from cognitively normal individuals with Aβ plaques (NwAβ) based on Aβ plaque detection is challenging. It has been observed that butyrylcholinesterase (BChE) accumulates in plaques preferentially in AD. Thus, detecting BChE-associated plaques has the potential as an improved AD biomarker. We present Aβ, thioflavin-S, and BChE quantification of 26 postmortem brain tissues; AD (n = 8), NwAβ (n = 6), cognitively normal without plaques (n = 8), and other common dementias including corticobasal degeneration, frontotemporal dementia with tau, dementia with Lewy bodies, and vascular dementia. Pathology burden in the orbitofrontal cortex, entorhinal cortex, amygdala, and hippocampal formation was determined and compared. The predictive value of Aβ and BChE quantification was determined, via receiver-operating characteristic plots, to evaluate their AD diagnostic performance using sensitivity, specificity, and area under curve (AUC) metrics. In general, Aβ and BChE-associated pathology were greater in AD, particularly in the orbitofrontal cortex. In this region, the largest increase (9.3-fold) was in BChE-associated pathology, observed between NwAβ and AD, due to the virtual absence of BChE-associated plaques in NwAβ brains. Furthermore, BChE did not associate with pathology of the other dementias. In this sample, BChE-associated pathology provided better diagnostic performance (AUC = 1.0, sensitivity/specificity = 100% /100%) when compared to Aβ (AUC = 0.98, 100% /85.7%). These findings highlight the predictive value of BChE as a biomarker for AD that could facilitate timely disease diagnosis and management.

Premature awakening and underuse of neuromuscular monitoring in a registry of patients with butyrylcholinesterase deficiency.

PubMed

Thomsen, J L; Nielsen, C V; Palmqvist, D F; Gätke, M R

2015-07-01

Patients with butyrylcholinesterase (BChE) deficiency can experience prolonged paralysis after receiving suxamethonium or mivacurium. We hypothesized that patients suspected of BChE deficiency had a higher risk of being awakened while paralysed and having respiratory complications if neuromuscular monitoring was not applied before awakening. We retrospectively included patients referred to the Danish Cholinesterase Research Unit between 2004 and 2012 on suspicion of BChE deficiency. We collected data on genotype, BChE activity, neuromuscular blocking agents administered, neuromuscular monitoring, and postoperative respiratory complications, defined as arterial oxygen desaturation <90%, assisted ventilation, reintubation of the trachea, and pulmonary aspiration. Patients were classified as prematurely awakened if anaesthesia had been terminated while the patient was still paralysed. We included 123 patients. Neuromuscular monitoring was applied before awakening in 48 (39%) patients. A nerve stimulator was never used or only after attempted awakening in the remaining 75 (61%) patients. Premature awakening occurred in 75 (100%) and 14 (29%) of the unmonitored and monitored patients, respectively (P<0.001, Fisher's exact test). In 11 of the monitored patients, the results of neuromuscular monitoring were interpreted as equipment failure or were disregarded. Respiratory complications occurred in 19 (25%) and five (10%) of the unmonitored and monitored patients, respectively (P=0.06). Patients with BChE deficiency are at higher risk of being awakened while paralysed if neuromuscular monitoring is not applied or used; neuromuscular monitoring is recommended whenever a neuromuscular blocking agent is administered. © The Author 2015. Published by Oxford University Press on behalf of the British Journal of Anaesthesia. All rights reserved. For Permissions, please email: journals.permissions@oup.com.

Butyrylcholinesterase Levels on Admission Predict Severity and 12-Month Mortality in Hospitalized AIDS Patients

PubMed Central

Xu, Lijun; Huang, Ying; Yang, Zongxing; Sun, Jia; Xu, Yan; Zheng, Jinlei; Kinloch, Sabine; Yin, Michael T.; Weng, Honglei

2018-01-01

Background Butyrylcholinesterase (BChE) is synthesized mainly in the liver and an important marker in many infectious/inflammatory diseases, but its role in acquired immunodeficiency syndrome (AIDS) patients is not clear. We wished to ascertain if BChE level is associated with the progression/prognosis of AIDS patients. Methods BChE levels (in U/L) were measured in 505 patients; <4500 was defined as “low” and ≥4500 as “normal.” Associations between BChE level and CD4 count, WHO stage, body mass index (BMI), C-reactive protein (CRP) level, and duration of hospitalization were assessed. Kaplan–Meier curves and Cox proportional hazards model were used to assess associations between low BChE levels and mortality, after adjustment for age, CD4 count, WHO stage, and laboratory parameters. Results A total of 129 patients (25.5%) had a lower BChE level. BChE was closely associated with CD4 count, WHO stage, CRP level, and BMI (all P < 0.001). Eighty-four patients (16.6%) died in the first year of follow-up. One-year survival was 64.5 ± 4.5% for patients with low BChE and 87.6 ± 1.8% for those with normal BChE (log-rank, P < 0.001). After adjustment for sex, age, BMI, WHO stage, and CD4 count, as well as serum levels of hemoglobin, sodium, and albumin, the hazard ratio was 1.8 (95% confidence interval, 1.0–3.2) for patients with a low BChE compared with those with a normal BChE (P = 0.035). Conclusion BChE level is associated with HIV/AIDS severity and is an independent risk factor for increased mortality in AIDS patients. PMID:29736152

The chemistry of aminoguanidine derivatives - preparation, crystal structure, thermal properties, and molecular docking studies of aminoguanidinium salts of several carboxylic acids

NASA Astrophysics Data System (ADS)

Selvakumar, Rajendran; Geib, Steven J.; Muthu Sankar, Aathi; Premkumar, Thathan; Govindarajan, Subbaiah

2015-11-01

The reaction of aminoguanidine bicarbonate (Amg) with oxamic, oxalic, malonic and sulfoacetic acids yielded (AmgH)H2NOC-COO (1), OOC-CONHNHC(NH2)NH2 (2) (AmgH)HOOC-CH2-COO (3) and O3S-CH2-CONHNHC(NH2)NH2 (4), respectively. For the first time, we studied the salt-forming ability of aminoguanidine with several carboxylic acids, such as oxamic, oxalic, malonic and sulphoacetic acids. We also compared the structural and thermal properties of these salts. Oxamic and malonic acids form only mono-aminoguanidinium salts, whereas oxalic acid mainly forms di-aminoguanidinium oxalate. In addition, oxalic acid forms guanylhydrazido-oxalic acid which exists as zwitter ion. Unlike other acids, sulfoacetic acid readily forms only the zwitter ionic salts (2-guanylhydrazido-oxo-methanesulfonic acid) rather than the usual simple salt. This result may be a result of the highly acidic nature of the sulfonic group, which favors acid catalyzed condensation. More significantly, for the first time, the ability guanylhydrazido-oxalic acid (2) and 2-guanylhydrazido-oxo-methanesulfonic acid (4) to inhibit human butyrylcholinesterase (human BChE) receptor has been studied with a molecular docking approach. The binding of the compounds to human BChE was examined as it is crucial to understanding the biological significance of aminoguanidine derivatives. The compounds were identified and characterized by analytical, FT-IR spectroscopic and thermal studies. Furthermore, the structures of compounds 1, 2 and 4 were confirmed by single X-ray diffraction studies. Compounds 1 and 2 crystallized in a monoclinic crystal system with P21/c and Cc space groups, respectively, whereas compound 4 crystalized in an orthorhombic system with a Pbca space group. All the compounds (1-4) underwent endo- followed by exothermic decomposition in the temperature range from 130 to 600 °C to yield gaseous products.

Sample Preparation Report of the Fourth OPCW Confidence Building Exercise on Biomedical Sample Analysis

DOE Office of Scientific and Technical Information (OSTI.GOV)

Udey, R. N.; Corzett, T. H.; Alcaraz, A.

Following the successful completion of the 3rd biomedical confidence building exercise (February 2013 – March 2013), which included the analysis of plasma and urine samples spiked at low ppb levels as part of the exercise scenario, another confidence building exercise was targeted to be conducted in 2014. In this 4th exercise, it was desired to focus specifically on the analysis of plasma samples. The scenario was designed as an investigation of an alleged use of chemical weapons where plasma samples were collected, as plasma has been reported to contain CWA adducts which remain present in the human body for severalmore » weeks (Solano et al. 2008). In the 3rd exercise most participants used the fluoride regeneration method to analyze for the presence of nerve agents in plasma samples. For the 4th biomedical exercise it was decided to evaluate the analysis of human plasma samples for the presence/absence of the VX adducts and aged adducts to blood proteins (e.g., VX-butyrylcholinesterase (BuChE) and aged BuChE adducts using a pepsin digest technique to yield nonapeptides; or equivalent). As the aging of VX-BuChE adducts is relatively slow (t1/2 = 77 hr at 37 °C [Aurbek et al. 2009]), soman (GD), which ages much more quickly (t1/2 = 9 min at 37 °C [Masson et al. 2010]), was used to simulate an aged VX sample. Additional objectives of this exercise included having laboratories assess novel OP-adducted plasma sample preparation techniques and analytical instrumentation methodologies, as well as refining/designating the reporting formats for these new techniques.« less

Metformin and Its Sulfenamide Prodrugs Inhibit Human Cholinesterase Activity.

PubMed

Markowicz-Piasecka, Magdalena; Sikora, Joanna; Mateusiak, Łukasz; Mikiciuk-Olasik, Elżbieta; Huttunen, Kristiina M

2017-01-01

The results of epidemiological and pathophysiological studies suggest that type 2 diabetes mellitus (T2DM) may predispose to Alzheimer's disease (AD). The two conditions present similar glucose levels, insulin resistance, and biochemical etiologies such as inflammation and oxidative stress. The diabetic state also contributes to increased acetylcholinesterase (AChE) activity, which is one of the factors leading to neurodegeneration in AD. The aim of this study was to assess in vitro the effects of metformin, phenformin, and metformin sulfenamide prodrugs on the activity of human AChE and butyrylcholinesterase (BuChE) and establish the type of inhibition. Metformin inhibited 50% of the AChE activity at micromolar concentrations (2.35  μ mol/mL, mixed type of inhibition) and seemed to be selective towards AChE since it presented low anti-BuChE activity. The tested metformin prodrugs inhibited cholinesterases (ChE) at nanomolar range and thus were more active than metformin or phenformin. The cyclohexyl sulfenamide prodrug demonstrated the highest activity towards both AChE (IC 50  = 890 nmol/mL, noncompetitive inhibition) and BuChE (IC 50  = 28 nmol/mL, mixed type inhibition), while the octyl sulfenamide prodrug did not present anti-AChE activity, but exhibited mixed inhibition towards BuChE (IC 50  = 184 nmol/mL). Therefore, these two bulkier prodrugs were concluded to be the most selective compounds for BuChE over AChE. In conclusion, it was demonstrated that biguanides present a novel class of inhibitors for AChE and BuChE and encourages further studies of these compounds for developing both selective and nonselective inhibitors of ChEs in the future.

Combined Cocaine Hydrolase Gene Transfer and Anti-Cocaine Vaccine Synergistically Block Cocaine-Induced Locomotion

PubMed Central

Carroll, Marilyn E.; Zlebnik, Natalie E.; Anker, Justin J.; Kosten, Thomas R.; Orson, Frank M.; Shen, Xiaoyun; Kinsey, Berma; Parks, Robin J.; Gao, Yang; Brimijoin, Stephen

2012-01-01

Mice and rats were tested for reduced sensitivity to cocaine-induced hyper-locomotion after pretreatment with anti-cocaine antibody or cocaine hydrolase (CocH) derived from human butyrylcholinesterase (BChE). In Balb/c mice, direct i.p. injection of CocH protein (1 mg/kg) had no effect on spontaneous locomotion, but it suppressed responses to i.p. cocaine up to 80 mg/kg. When CocH was injected i.p. along with a murine cocaine antiserum that also did not affect spontaneous locomotion, there was no response to any cocaine dose. This suppression of locomotor activity required active enzyme, as it was lost after pretreatment with iso-OMPA, a selective BChE inhibitor. Comparable results were obtained in rats that developed high levels of CocH by gene transfer with helper-dependent adenoviral vector, and/or high levels of anti-cocaine antibody by vaccination with norcocaine hapten conjugated to keyhole limpet hemocyanin (KLH). After these treatments, rats were subjected to a locomotor sensitization paradigm involving a “training phase" with an initial i.p. saline injection on day 1 followed by 8 days of repeated cocaine injections (10 mg/kg, i.p.). A 15-day rest period then ensued, followed by a final “challenge" cocaine injection. As in mice, the individual treatment interventions reduced cocaine-stimulated hyperactivity to a modest extent, while combined treatment produced a greater reduction during all phases of testing compared to control rats (with only saline pretreatment). Overall, the present results strongly support the view that anti-cocaine vaccine and cocaine hydrolase vector treatments together provide enhanced protection against the stimulatory actions of cocaine in rodents. A similar combination therapy in human cocaine users might provide a robust therapy to help maintain abstinence. PMID:22912888

Proline-Based Carbamates as Cholinesterase Inhibitors.

PubMed

Pizova, Hana; Havelkova, Marketa; Stepankova, Sarka; Bak, Andrzej; Kauerova, Tereza; Kozik, Violetta; Oravec, Michal; Imramovsky, Ales; Kollar, Peter; Bobal, Pavel; Jampilek, Josef

2017-11-14

Series of twenty-five benzyl (2S)-2-(arylcarbamoyl)pyrrolidine-1-carboxylates was prepared and completely characterized. All the compounds were tested for their in vitro ability to inhibit acetylcholinesterase (AChE) and butyrylcholinesterase (BChE), and the selectivity of compounds to individual cholinesterases was determined. Screening of the cytotoxicity of all the compounds was performed using a human monocytic leukaemia THP-1 cell line, and the compounds demonstrated insignificant toxicity. All the compounds showed rather moderate inhibitory effect against AChE; benzyl (2 S )-2-[(2-chlorophenyl)carbamoyl]pyrrolidine-1-carboxylate (IC 50 = 46.35 μM) was the most potent agent. On the other hand, benzyl (2 S )-2-[(4-bromophenyl)-] and benzyl (2 S )-2-[(2-bromophenyl)carbamoyl]pyrrolidine-1-carboxylates expressed anti-BChE activity (IC 50 = 28.21 and 27.38 μM, respectively) comparable with that of rivastigmine. The ortho -brominated compound as well as benzyl (2 S )-2-[(2-hydroxyphenyl)carbamoyl]pyrrolidine-1-carboxylate demonstrated greater selectivity to BChE. The in silico characterization of the structure-inhibitory potency for the set of proline-based carbamates considering electronic, steric and lipophilic properties was provided using comparative molecular surface analysis (CoMSA) and principal component analysis (PCA). Moreover, the systematic space inspection with splitting data into the training/test subset was performed to monitor the statistical estimators performance in the effort to map the probability-guided pharmacophore pattern. The comprehensive screening of the AChE/BChE profile revealed potentially relevant structural and physicochemical features that might be essential for mapping of the carbamates inhibition efficiency indicating qualitative variations exerted on the reaction site by the substituent in the 3'-/4'-position of the phenyl ring. In addition, the investigation was completed by a molecular docking study of recombinant human AChE.

Modification of pharmacokinetic and abuse-related effects of cocaine by human-derived cocaine hydrolase in monkeys

PubMed Central

Schindler, Charles W.; Justinova, Zuzana; Lafleur, David; Woods, Doug; Roschke, Viktor; Hallak, Hussein; Sklair-Tavron, Liora; Redhi, Godfrey H.; Yasar, Sevil; Bergman, Jack; Goldberg, Steven R.

2011-01-01

Although substantial research effort has focused on developing pharmacological treatments for cocaine abuse, no effective medications have been developed. Recent studies show that enzymes that metabolize cocaine in the periphery, forestalling its entry into the brain, can prevent cocaine toxicity and its behavioral effects in rodents. Here we report on effects of one such enzyme (Albu-CocH) on the pharmacokinetic and behavioral effects of cocaine in squirrel monkeys. Albu-CocH was developed from successive mutations of human butyrylcholinesterase (BChE) and has 1000-fold greater catalytic activity against cocaine than naturally occurring BChE. Pharmacokinetic studies showed that Albu-CocH (5 mg/kg) had a half-life of 56.6 hours in squirrel monkeys. In these studies, plasma levels of cocaine following i.v. 1 mg/kg cocaine were reduced two hours after administration of Albu-CocH, whereas plasma levels of the cocaine metabolite ecgonine methyl ester were increased. These effects were still evident 72 hrs following Albu-CocH administration. In behavioral experiments in monkeys, pretreatment with 5 mg/kg Albu-CocH dramatically decreased self-administration of a reinforcing dose of i.v. cocaine (30 μg/kg/injection) for over 24 hours. Pretreatment with 5 mg/kg Albu-CocH also attenuated the reinstatement of extinguished cocaine self-administration by an i.v. priming injection of cocaine (0.1 or 0.3 mg/kg) and, in separate studies, attenuated the discriminative stimulus effects of cocaine. The ability of Albu-CocH to attenuate the abuse-related effects of cocaine in squirrel monkeys indicates that further investigation of BChE mutants as potential treatment for cocaine abuse and toxicity is warranted. PMID:22264200

Rational design of an enzyme mutant for anti-cocaine therapeutics

NASA Astrophysics Data System (ADS)

Zheng, Fang; Zhan, Chang-Guo

2008-09-01

(-)-Cocaine is a widely abused drug and there is no available anti-cocaine therapeutic. The disastrous medical and social consequences of cocaine addiction have made the development of an effective pharmacological treatment a high priority. An ideal anti-cocaine medication would be to accelerate (-)-cocaine metabolism producing biologically inactive metabolites. The main metabolic pathway of cocaine in body is the hydrolysis at its benzoyl ester group. Reviewed in this article is the state-of-the-art computational design of high-activity mutants of human butyrylcholinesterase (BChE) against (-)-cocaine. The computational design of BChE mutants have been based on not only the structure of the enzyme, but also the detailed catalytic mechanisms for BChE-catalyzed hydrolysis of (-)-cocaine and (+)-cocaine. Computational studies of the detailed catalytic mechanisms and the structure-and-mechanism-based computational design have been carried out through the combined use of a variety of state-of-the-art techniques of molecular modeling. By using the computational insights into the catalytic mechanisms, a recently developed unique computational design strategy based on the simulation of the rate-determining transition state has been employed to design high-activity mutants of human BChE for hydrolysis of (-)-cocaine, leading to the exciting discovery of BChE mutants with a considerably improved catalytic efficiency against (-)-cocaine. One of the discovered BChE mutants (i.e., A199S/S287G/A328W/Y332G) has a ˜456-fold improved catalytic efficiency against (-)-cocaine. The encouraging outcome of the computational design and discovery effort demonstrates that the unique computational design approach based on the transition-state simulation is promising for rational enzyme redesign and drug discovery.

GC-MS and LC-MS analysis of nerve agents in body fluids: intra-laboratory verification test using spiked plasma and urine samples.

PubMed

Koller, Marianne; Becker, Christian; Thiermann, Horst; Worek, Franz

2010-05-15

The purpose of this study was to check the applicability of different analytical methods for the identification of unknown nerve agents in human body fluids. Plasma and urine samples were spiked with nerve agents (plasma) or with their metabolites (urine) or were left blank. Seven random samples (35% of all samples) were selected for the verification test. Plasma was worked up for unchanged nerve agents and for regenerated nerve agents after fluoride-induced reactivation of nerve agent-inhibited butyrylcholinesterase. Both extracts were analysed by GC-MS. Metabolites were extracted from plasma and urine, respectively, and were analysed by LC-MS. The urinary metabolites and two blank samples could be identified without further measurements, plasma metabolites and blanks were identified in six of seven samples. The analysis of unchanged nerve agent provided five agents/blanks and the sixth agent after further investigation. The determination of the regenerated agents also provided only five clear findings during the first screening because of a rather noisy baseline. Therefore, the sample preparation was extended by a size exclusion step performed before addition of fluoride which visibly reduced baseline noise and thus improved identification of the two missing agents. The test clearly showed that verification should be performed by analysing more than one biomarker to ensure identification of the agent(s). Copyright (c) 2010 Elsevier B.V. All rights reserved.

Ionic liquid mediated synthesis of mono- and bis-spirooxindole-hexahydropyrrolidines as cholinesterase inhibitors and their molecular docking studies.

PubMed

Kia, Yalda; Osman, Hasnah; Kumar, Raju Suresh; Basiri, Alireza; Murugaiyah, Vikneswaran

2014-02-15

One pot, three-component reaction of 1-acryloyl-3,5-bisarylmethylidenepiperidin-4-ones with isatin and sarcosine in molar ratios of 1:1:1 and 1:2:2 furnished to mono- and bis-spiropyrrolidine heterocyclic hybrids comprising functionalized piperidine, pyrrolidine and oxindole structural motifs. Both mono and bis-spiropyrrolidines displayed good inhibitory activity against acetylcholinesterase (AChE) with IC₅₀ values of 2.36-9.43 μM. For butyrylcholinesterase (BChE), mono-cycloadducts in series 8 with IC₅₀ values of lower than 10 μM displayed better inhibitory activities than their bis-cycloadduct analogs in series 9 with IC₅₀ values of 7.44-19.12 μM. The cycloadducts 9j and 8e were found to be the most potent AChE and BChE inhibitors with IC₅₀ values of 2.35 and 3.21 μM, respectively. Compound 9j was found to be competitive inhibitor of AChE while compound 8e was a mixed-mode inhibitor of BChE with calculated Ki values of 2.01 and 6.76 μM, respectively. Molecular docking on Torpedo californica AChE and human BChE showed good correlation between IC₅₀ values and free binding energy values of the synthesized compounds docked into the active site of the enzymes. Copyright © 2014 Elsevier Ltd. All rights reserved.

Discorhabdin alkaloids from Antarctic Latrunculia spp. sponges as a new class of cholinesterase inhibitors.

PubMed

Botić, Tanja; Defant, Andrea; Zanini, Pietro; Žužek, Monika Cecilija; Frangež, Robert; Janussen, Dorte; Kersken, Daniel; Knez, Željko; Mancini, Ines; Sepčić, Kristina

2017-08-18

The brominated pyrroloiminoquinone alkaloids discorhabdins B, L and G and 3-dihydro-7,8- dehydrodiscorhabdin C, isolated from methanol extracts of two specimens of Latrunculia sp. sponges collected near the Antarctic Peninsula, are here demonstrated for the first time to be reversible competitive inhibitors of cholinesterases. They showed K i for electric eel acetylcholinesterase of 1.6-15.0 μM, for recombinant human acetylcholinesterase of 22.8-98.0 μM, and for horse serum butyrylcholinesterase of 5.0-76.0 μM. These values are promising when compared to the current cholinesterase inhibitors used for treatment of patients with Alzheimer's disease, to counteract the acetylcholine deficiency in the brain. Good correlation was obtained between IC 50 data and results by molecular docking calculation on the binding interactions within the acetylcholinesterase active site, which also indicated the moieties in discorhabdin structures involved. To avoid unwanted peripheral side effects that can appear in patients using some acetylcholinesterase inhibitors, electrophysiological experiments were carried out on one of the most active of these compounds, discorhabdin G, which confirmed that it had no detectable undesirable effects on neuromuscular transmission and skeletal muscle function. These findings are promising for development of cholinesterase inhibitors based on the scaffold of discorhabdins, as potential new agents for treatment of patients with Alzheimer's disease. Copyright © 2017 Elsevier Masson SAS. All rights reserved.

Essential oil compositions and anticholinesterase activities of two edible plants Tragopogon latifolius var. angustifolius and Lycopsis orientalis.

PubMed

Ertaş, Abdulselam; Gören, Ahmet C; Boğa, Mehmet; Yeşil, Yeter; Kolak, Ufuk

2014-01-01

This is the first report in the literature on essential oil compositions of Tragopogon latifolius var. angustifolius and Lycopsis orientalis which were analysed by using GC-FID and GC-MS techniques. The main constituents of T. latifolius var. angustifolius were identified as α-selinene (10.5%), 2,5-di-tert octyl-p-benzoquinone (9.5%) and valencene (7.0%); however, the main components of L. orientalis were identified as heptacosane (10.5%), τ-muurolene (9.6%) and tetratetracontane (9.4%). The essential oils of T. latifolius var. angustifolius and L. orientalis species exhibited moderate inhibitory activity against acetyl- and butyryl-cholinesterase enzymes at 200 μg/mL.

Compounds from the aerial parts of Piper bavinum and their anti-cholinesterase activity.

PubMed

Dung, Hoang Viet; Cuong, To Dao; Chinh, Nguyen Minh; Quyen, Do; Kim, Jeong Ah; Byeon, Jeong Su; Woo, Mi Hee; Choi, Jae Sui; Min, Byung Sun

2015-01-01

A new alkenylphenol, bavinol A (1), together with six known compounds (2-7) were isolated from the aerial parts of Piper bavinum (Piperaceae). The chemical structures of these compounds were determined by spectroscopic analyses including 2D NMR spectroscopy. The anti-Alzheimer effects of compounds 1-7 were evaluated from acetylcholinesterase (AChE) and butyrylcholinesterase (BChE) inhibitory activity assays. Bavinol A (1), ampelopsin (3), and violanthin (4) exhibited AChE inhibitory activities with IC50 values of 29.80, 59.47 and 79.80 μM. Compound 1 also showed the most potent BChE inhibitory activity with an IC50 value of 19.25 μM.

Novel coumarin derivatives bearing N-benzyl pyridinium moiety: potent and dual binding site acetylcholinesterase inhibitors.

PubMed

Alipour, Masoumeh; Khoobi, Mehdi; Foroumadi, Alireza; Nadri, Hamid; Moradi, Alireza; Sakhteman, Amirhossein; Ghandi, Mehdi; Shafiee, Abbas

2012-12-15

A novel series of coumarin derivatives linked to benzyl pyridinium group were synthesized and biologically evaluated as inhibitors of both acetylcholinesterase (AChE) and butyrylcholinesterase (BuChE). The enzyme inhibitory activity of synthesized compounds was measured using colorimetric Ellman's method. It was revealed that compounds 3e, 3h, 3l, 3r and 3s have shown higher activity compared with donepezil hydrochloride as standard drug. Most of the compounds in these series had nanomolar range IC(50) in which compound 3r (IC(50) = 0.11 nM) was the most active compound against acetylcholinesterase enzyme. Copyright © 2012 Elsevier Ltd. All rights reserved.

Quantitative distributions of different cholinesterases and inhibition of acetylcholinesterase by metidathion and paraquat in alimentary canal of common carp.

PubMed

Láng, G; Kufcsák, O; Szegletes, T; Nemcsók, J

1997-07-01

1. The cholinesterases play an important role in the innervation of organs. The ratio of solubilized to membrane-bound cholinesterase and the quantitative distributions of acetylcholinesterase and butyrylcholinesterase were measured in different segments of the gut of carp (Cyprinus carpio) connected with different types of nerve-muscle synapses in different parts of the alimentary tract. 2. The inhibition of acetylcholinesterase (EC 3.1.1.7.) by the herbicide paraquat and the insecticide metidathion was measured in different parts of the gut of carp. 3. Metidathion and paraquat significantly decreased the activity of acetylcholinesterase in different segments of the alimentary tract of common carp, in a concentration-dependent manner.

An in vitro and in vivo evaluation of the efficacy of recombinant human liver prolidase as a catalytic bioscavenger of chemical warfare nerve agents.

PubMed

Rezk, Peter E; Zdenka, Pierre; Sabnekar, Praveena; Kajih, Takwen; Mata, David G; Wrobel, Chester; Cerasoli, Douglas M; Chilukuri, Nageswararao

2015-01-01

In this study, we determined the ability of recombinant human liver prolidase to hydrolyze nerve agents in vitro and its ability to afford protection in vivo in mice. Using adenovirus containing the human liver prolidase gene, the enzyme was over expressed by 200- to 300-fold in mouse liver and purified to homogeneity by affinity and gel filtration chromatography. The purified enzyme hydrolyzed sarin, cyclosarin and soman with varying rates of hydrolysis. The most efficient hydrolysis was with sarin, followed by soman and by cyclosarin {apparent kcat/Km [(1.9 ± 0.3), (1.7 ± 0.2), and (0.45 ± 0.04)] × 10(5 )M(-1 )min(-1), respectively}; VX and tabun were not hydrolyzed by the recombinant enzyme. The enzyme hydrolyzed P (+) isomers faster than the P (-) isomers. The ability of recombinant human liver prolidase to afford 24 hour survival against a cumulative dose of 2 × LD50 of each nerve agent was investigated in mice. Compared to mice injected with a control virus, mice injected with the prolidase expressing virus contained (29 ± 7)-fold higher levels of the enzyme in their blood on day 5. Challenging these mice with two consecutive 1 × LD50 doses of sarin, cyclosarin, and soman resulted in the death of all animals within 5 to 8 min from nerve agent toxicity. In contrast, mice injected with the adenovirus expressing mouse butyrylcholinesterase, an enzyme which is known to afford protection in vivo, survived multiple 1 × LD50 challenges of these nerve agents and displayed no signs of toxicity. These results suggest that, while prolidase can hydrolyze certain G-type nerve agents in vitro, the enzyme does not offer 24 hour protection against a cumulative dose of 2 × LD50 of G-agents in mice in vivo.

Butyrylcholinesterase in guinea pig lung lavage: a novel biomarker to assess lung injury following inhalation exposure to nerve agent VX.

PubMed

Graham, Jacob R; Wright, Benjamin S; Rezk, Peter E; Gordon, Richard K; Sciuto, Alfred M; Nambiar, Madhusoodana P

2006-06-01

Respiratory disturbances play a central role in chemical warfare nerve agent (CWNA) induced toxicity; they are the starting point of mass casualty and the major cause of death. We developed a microinstillation technique of inhalation exposure to nerve agent VX and assessed lung injury by biochemical analysis of the bronchoalveolar lavage fluid (BALF). Here we demonstrate that normal guinea pig BALF has a significant amount of cholinesterase activity. Treatment with Huperzine A, a specific inhibitor of acetylcholinesterase (AChE), showed that a minor fraction of BALF cholinesterase is AChE. Furthermore, treatment with tetraisopropyl pyrophosphoramide (iso-OMPA), a specific inhibitor of butyrylcholinesterase (BChE), inhibited more than 90% of BChE activity, indicating the predominance of BChE in BALF. A predominance of BChE expression in the lung lavage was seen in both genders. Substrate specific inhibition indicated that nearly 30% of the cholinesterase in lung tissue homogenate is AChE. BALF and lung tissue AChE and BChE activities were strongly inhibited in guinea pigs exposed for 5 min to 70.4 and 90.4 microg/m3 VX and allowed to recover for 15 min. In contrast, BALF AChE activity was increased 63% and 128% and BChE activity was increased 77% and 88% after 24 h of recovery following 5 min inhalation exposure to 70.4 microg/m3 and 90.4 mg/m3 VX, respectively. The increase in BALF AChE and BChE activity was dose dependent. Since BChE is synthesized in the liver and present in the plasma, an increase in BALF indicates endothelial barrier injury and leakage of plasma into lung interstitium. Therefore, a measure of increased levels of AChE and BChE in the lung lavage can be used to determine the chronology of barrier damage as well as the extent of lung injury following exposure to chemical warfare nerve agents.

Characterization of a Novel BCHE “Silent” Allele: Point Mutation (p.Val204Asp) Causes Loss of Activity and Prolonged Apnea with Suxamethonium

PubMed Central

Delacour, Herve; Lushchekina, Sofya; Mabboux, Isabelle; Bousquet, Aurore; Ceppa, Franck; Schopfer, Lawrence M.; Lockridge, Oksana; Masson, Patrick

2014-01-01

Butyrylcholinesterase deficiency is characterized by prolonged apnea after the use of muscle relaxants (suxamethonium or mivacurium) in patients who have mutations in the BCHE gene. Here, we report a case of prolonged neuromuscular block after administration of suxamethonium leading to the discovery of a novel BCHE variant (c.695T>A, p.Val204Asp). Inhibition studies, kinetic analysis and molecular dynamics were undertaken to understand how this mutation disrupts the catalytic triad and determines a “silent” phenotype. Low activity of patient plasma butyrylcholinesterase with butyrylthiocholine (BTC) and benzoylcholine, and values of dibucaine and fluoride numbers fit with heterozygous atypical silent genotype. Electrophoretic analysis of plasma BChE of the proband and his mother showed that patient has a reduced amount of tetrameric enzyme in plasma and that minor fast-moving BChE components: monomer, dimer, and monomer-albumin conjugate are missing. Kinetic analysis showed that the p.Val204Asp/p.Asp70Gly-p.Ala539Thr BChE displays a pure Michaelian behavior with BTC as the substrate. Both catalytic parameters Km = 265 µM for BTC, two times higher than that of the atypical enzyme, and a low Vmax are consistent with the absence of activity against suxamethonium. Molecular dynamic (MD) simulations showed that the overall effect of the mutation p.Val204Asp is disruption of hydrogen bonding between Gln223 and Glu441, leading Ser198 and His438 to move away from each other with subsequent disruption of the catalytic triad functionality regardless of the type of substrate. MD also showed that the enzyme volume is increased, suggesting a pre-denaturation state. This fits with the reduced concentration of p.Ala204Asp/p.Asp70Gly-p.Ala539Thr tetrameric enzyme in the plasma and non-detectable fast moving-bands on electrophoresis gels. PMID:25054547

Postnatal growth hormone deficiency in growing rats causes marked decline in the activity of spinal cord acetylcholinesterase but not butyrylcholinesterase.

PubMed

Koohestani, Faezeh; Brown, Chester M; Meisami, Esmail

2012-11-01

The effects of growth hormone (GH) deficiency on the developmental changes in the abundance and activity of cholinesterase enzymes were studied in the developing spinal cord (SC) of postnatal rats by measuring the specific activity of acetylcholinesterase (AChE), a marker for cholinergic neurons and their synaptic compartments, and butyrylcholinesterase (BuChE), a marker for glial cells and neurovascular cells. Specific activities of these two enzymes were measured in SC tissue of 21- and 90 day-old (P21, weaning age; P90, young adulthood) GH deficient spontaneous dwarf (SpDwf) mutant rats which lack anterior pituitary and circulating plasma GH, and were compared with SC tissue of normal age-matched control animals. Assays were carried out for AChE and BuChE activity in the presence of their specific chemical inhibitors, BW284C51 and iso-OMPA, respectively. Results revealed that mean AChE activity was markedly and significantly reduced [28% at P21, 49% at P90, (p<0.01)] in the SC of GH deficient rats compared to age-matched controls. GH deficiency had a higher and more significant effect on AChE activity of the older (P90) rats than the younger ones (P21) ones. In contrast, BuChE activity in SC showed no significant changes in GH deficient rats at either of the two ages studied. Results imply that, in the absence of pituitary GH, the postnatal proliferation of cholinergic synapses in the rat SC, a CNS structure, where AChE activity is abundant, is markedly reduced during both the pre- and postweaning periods; more so in the postweaning than preweaning ages. In contrast, the absence of any effects on BuChE activity implies that GH does not affect the development of non-neuronal elements, e.g., glia, as much as the neuronal and synaptic compartments of the developing rat SC. Copyright © 2012 ISDN. Published by Elsevier Ltd. All rights reserved.

Novel neuroprotective and hepatoprotective effects of citric acid in acute malathion intoxication.

PubMed

Abdel-Salam, Omar M E; Youness, Eman R; Mohammed, Nadia A; Yassen, Noha N; Khadrawy, Yasser A; El-Toukhy, Safinaz Ebrahim; Sleem, Amany A

2016-12-01

To study the effect of citric acid given alone or combined with atropine on brain oxidative stress, neuronal injury, liver damage, and DNA damage of peripheral blood lymphocytes induced in the rat by acute malathion exposure. Rats were received intraperitoneal (i.p.) injection of malathion 150 mg/kg along with citric acid (200 or 400 mg/kg, orally), atropine (1 mg/kg, i.p.) or citric acid 200 mg/kg + atropine 1 mg/kg and euthanized 4 h later. Malathion resulted in increased lipid peroxidation (malondialdehyde) and nitric oxide concentrations accompanied with a decrease in brain reduced glutathione, glutathione peroxidase (GPx) activity, total antioxidant capacity (TAC) and glucose concentrations. Paraoxonase-1, acetylcholinesterase (AChE) and butyrylcholinesterase activities decreased in brain as well. Liver aspartate aminotransferase and alanine aminotransferase activities were raised. The comet assay showed increased DNA damage of peripheral blood lymphocytes. Histological damage and increased expression of inducible nitric oxide synthase (iNOS) were observed in brain and liver. Citric acid resulted in decreased brain lipid peroxidation and nitric oxide. Meanwhile, glutathione, GPx activity, TAC capacity and brain glucose level increased. Brain AChE increased but PON1 and butyrylcholinesterase activities decreased by citric acid. Liver enzymes, the percentage of damaged blood lymphocytes, histopathological alterations and iNOS expression in brain and liver was decreased by citric acid. Meanwhile, rats treated with atropine showed decreased brain MDA, nitrite but increased GPx activity, TAC, AChE and glucose. The drug also decreased DNA damage of peripheral blood lymphocytes, histopathological alterations and iNOS expression in brain and liver. The study demonstrates a beneficial effect for citric acid upon brain oxidative stress, neuronal injury, liver and DNA damage due to acute malathion exposure. Copyright © 2016 Hainan Medical University. Production and hosting by Elsevier B.V. All rights reserved.

A single mutation near the C-terminus in alpha/beta hydrolase fold protein family causes a defect in protein processing.

PubMed

De Jaco, Antonella; Kovarik, Zrinka; Comoletti, Davide; Jennings, Lori L; Gaietta, Guido; Ellisman, Mark H; Taylor, Palmer

2005-12-15

An Arg to Cys mutation in the extracellular domain of neuroligin-3 (NL3) was recently found in a twin set with autism [S. Jamain, H. Quach, C. Betancur, M. Rastam, C. Colineaux, I.C. Gillberg, H. Soderstrom, B. Giros, M. Leboyer, C. Gillberg, T. Bourgeron, Paris Autism Research International Sibpair Study, mutations of the X-linked genes encoding neuroligins NLGN3 and NLGN4 are associated with autism, Nat. Genet. 34 (2003) 27-29]. The Cys substitution in NL3 causes altered intracellular protein trafficking, intracellular retention and diminished association with its cognate partner, beta-neurexin [D. Comoletti, A. De Jaco, L.L. Jennings, R.E. Flynn, G. Gaietta, I. Tsigelny, M.H. Ellisman, P. Taylor, The R451C-neuroligin-3 mutation associated with autism reveals a defect in protein processing, J. Neurosci. 24 (2004) 4889-4893]. NL3, butyrylcholinesterase (BuChE), and acetylcholinesterase (AChE), as members of the (/(-hydrolase fold family of proteins, share over 30% of amino acid identity in their extracellular domains. In particular, Arg451 in NL3 is conserved in the alpha/beta-hydrolase fold family being homologous to Arg386 in BuChE and Arg395 in AChE. A Cys substitution at the homologous Arg in the BuChE was found studying post-succinylcholine apnea in an Australian population [T. Yen, B.N. Nightingale, J.C. Burns, D.R. Sullivan, P.M. Stewart, Butyrylcholinesterase (BCHE) genotyping for post-succinylcholine apnea in an Australian population, Clin. Chem. 49 (2003) 1297-308]. We have made the homologous mutation in the mouse AChE and BuChE genes and showed that the Arg to Cys mutations resulted in identical alterations in the cellular phenotype for the various members of the alpha/beta-hydrolase fold family proteins.

Identification of butyrylcholinesterase adducts after inhibition with isomalathion using mass spectrometry: difference in mechanism between (1R)- and (1S)-stereoisomers.

PubMed

Doorn, J A; Schall, M; Gage, D A; Talley, T T; Thompson, C M; Richardson, R J

2001-10-15

Previous kinetic studies found that butyrylcholinesterase (BChE) inhibited by (1R)-isomalathions readily reactivated, while enzyme inactivated by (1S)-isomers did not. This study tested the hypothesis that (1R)- and (1S)-isomers inhibit BChE by different mechanisms, yielding distinct adducts identifiable by peptide mass mapping with matrix-assisted laser desorption/ionization time-of-flight mass spectrometry (MALDI-TOF-MS). Equine BChE (EBChE) was inhibited to <10% of control activity with each isomer of isomalathion and the reference compound isoparathion methyl. Control and treated enzyme was digested with trypsin, and peptides were fractionated with HPLC. Separated and unseparated peptides were analyzed with MALDI-TOF-MS. Identity of an organophosphorus peptide adduct was confirmed by fragmentation using postsource decay analysis. EBChE inhibited by (1R)-isomalathions or (S)-isoparathion methyl readily reactivated after oxime treatment with 30-40% activity recovered. Enzyme inactivated by (1S)-isomalathions or (R)-isoparathion methyl recovered <2% and <5% activity, respectively, after oxime treatment. MALDI-TOF-MS analysis revealed that inhibition of EBChE by (1R)-isomalathions and (R)- or (S)-isoparathion methyl yielded O,S-dimethyl phosphate adducts. Enzyme inactivated by (1S)-isomalathions produced only O-methyl phosphate adduct. EBChE modified by (1R)-isomalathions or either enantiomer of isoparathion methyl yielded an O-methyl phosphate adduct as well. The results indicate that EBChE inhibition by (1R)-isomalathions proceeds with loss of diethyl thiosuccinate, but inactivation by (1S)-isomers occurs with loss of thiomethyl as the primary leaving group followed by rapid expulsion of diethyl thiosuccinate to yield an aged enzyme. Furthermore, the data suggest that aging of the O,S-dimethyl phosphate adduct occurs via an S(N)2 process with loss of thiomethyl. Copyright 2001 Academic Press.

Effects of energetic restriction diet on butyrylcholinesterase in obese women from southern Brazil - A longitudinal study.

PubMed

Santos, Willian Dos; Tureck, Luciane Viater; Saliba, Louise Farah; Schenknecht, Caroline Schovanz; Scaraboto, Débora; Souza, Ricardo Lehtonen R; Furtado-Alle, Lupe

2017-01-01

Butyrylcholinesterase (BChE) activity has been associated with obesity, lipid concentrations, and CHE2 locus phenotypes. This, the aim of this study was to evaluate the effects of an energetic restriction diet intervention on anthropometrical and biochemical variables and on absolute and relative BChE activity in CHE2 C5+ and CHE2 C5- individuals. One hundred eleven premenopausal obese women from Southern Brazil participated in an energetic restriction diet intervention (deficit of 2500 kJ/day) for 8 weeks. Their anthropometric and biochemical parameters were evaluated before and after the intervention. Plasma BChE activity was measured, and BChE bands in plasma and CHE2 locus phenotypes were detected by electrophoresis. The dietetic intervention decreased anthropometric and biochemical parameters as well as absolute BChE activity and relative activity of the G4 band. The CHE2 C5+ phenotype presented a different effect when compared with the CHE2 C5- phenotype. The CHE2 C5+ phenotype showed an effect in absolute BChE activity and in the relative activity of the G4 form, maintaining higher BChE activity regardless of the metabolic changes. In our study, 8 weeks was not sufficient time to lower the body mass index to normal, but it was enough to significantly reduce the absolute BChE activity, which became similar to the levels in nonobese individuals. CHE2 C5+ individuals were resistant to the decrease in BChE activity compared to CHE2 C5- individuals. This shows that the diet did not affect the CHE2 and G4 fraction complex and that the products of the CHE2 locus in association with BChE have a role in energy metabolism, maintaining high levels of enzymatic activity even after dietary intervention.

Piper betle leaves: profiling phenolic compounds by HPLC/DAD-ESI/MS(n) and anti-cholinesterase activity.

PubMed

Ferreres, Federico; Oliveira, Andreia P; Gil-Izquierdo, Angel; Valentão, Patrícia; Andrade, Paula B

2014-01-01

Piper betle L. is a widely distributed plant in the tropical and subtropical regions, its leaves being largely consumed as a masticator and mouth freshener. The purposes of this work were to characterise the phenolic profile of this species and to improve knowledge of its anti-cholinesterase properties. The phenolic composition of P. betle leaf aqueous and ethanol extracts was characterised by HPLC coupled with a diode-array detector and combined with electrospray ionisation tandem MS, and in vitro cholinesterase inhibitory capacity of both extracts was assessed by spectrophotometric microassays. The effect on neuronal cells (SH-SY5Y) viability was evaluated by 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide reduction and lactate dehydrogenase leakage. Twelve phenolic compounds, comprising a phenylpropanoid, five cinnamoyl and six flavonoids derivatives were identified in P. betle leaves. Hydroxychavicol was the major compound in both extracts; however, the aqueous extract presented a greater diversity of compounds. Both extracts showed strong activity against both acetyl- and butyrylcholinesterase, which can be due, at least partially, to the phenolic composition. Furthermore, the aqueous extract proved to be cytotoxic to human neuroblastoma cells at concentrations higher than 500 µg/mL. The results suggest that the consumption of P. betle leaves as an infusion can have a positive impact in the prevention and treatment of neurodegenerative diseases. Apigenin and luteolin derivatives are reported for the first time in this species. Copyright © 2014 John Wiley & Sons, Ltd.

Synthesis, Biological Evaluation and Molecular Docking Study of Hydrazone-Containing Pyridinium Salts as Cholinesterase Inhibitors.

PubMed

Parlar, Sulunay; Bayraktar, Gulsah; Tarikogullari, Ayse Hande; Alptüzün, Vildan; Erciyas, Ercin

2016-01-01

A series of pyridinium salts bearing alkylphenyl groups at 1 position and hydrazone structure at 4 position of the pyridinium ring were synthesized and evaluated for the inhibition of both acetylcholinesterase (AChE) and butyrylcholinesterase (BuChE) enzymes. The cholinesterase (ChE) inhibitory activity studies were carried out by using the Ellman's colorimetric method. All compounds displayed considerable AChE and BuChE inhibitory activity and some of the compounds manifested remarkable anti-AChE activity compared to the reference compound, galantamine. Among the title compounds, the series including benzofuran aromatic ring exhibited the best inhibitory activity both on AChE and BuChE enzymes. Compound 3b, 4-[2-(1-(benzofuran-2-yl)ethylidene)hydrazinyl]-1-(3-phenylpropyl)pyridinium bromide, was the most active compound with IC50 value of 0.23 (0.24) µM against enantiomeric excess (ee)AChE (human (h)AChE) while compound 3a, 4-[2-(1-(benzofuran-2-yl)ethylidene)hydrazinyl]-1-phenethylpyridinium bromide, was the most active compound with IC50 value of 0.95 µM against BuChE. Moreover, 3a and b exhibited higher activity than the reference compound galantamine (eeAChE (hAChE) IC50 0.43 (0.52) µM; BuChE IC50 14.92 µM). Molecular docking studies were carried out on 3b having highest inhibitory activity against AChE.

De novo amplification within a silent human cholinesterase gene in a family subjected to prolonged exposure to organophosphorus insecticides

DOE Office of Scientific and Technical Information (OSTI.GOV)

Prody, C.A.; Dreyfus, P.; Soreq, H.

1989-01-01

A 100-fold DNA amplification in the CHE gene, coding for serum butyrylcholinesterase (BtChoEase), was found in a farmer expressing silent CHE phenotype. Individuals homozygous for this gene display a defective serum BtChoEase and are particularly vulnerable to poisoning by agricultural organophosphorus insecticides, to which all members of this family had long been exposed. DNA blot hybridization with regional BtChoEase cDNA probes suggested that the amplification was most intense in regions encoding central sequences within BtChoEase cDNA, whereas distal sequences were amplified to a much lower extent. This is in agreement with the onion skin model, based on amplification of genesmore » in cultured cells and primary tumors. The amplification was absent in the grandparents but present at the same extent in one of their sons and in a grandson, with similar DNA blot hybridization patterns. In situ hybridization experiments localized the amplified sequences to the long arm of chromosome 3, close to the site where the authors previously mapped the CHE gene. Altogether, these observations suggest that the initial amplification event occurred early in embryogenesis, spermatogenesis, or oogenesis, where the CHE gene is intensely active and where cholinergic functioning was indicated to be physiologically necessary. These findings demonstrate a de novo amplification in apparently healthy individuals within an autosomal gene producing a target protein to an inhibitor.« less

Synthesis and acetylcholinesterase inhibitory activity of polyhydroxylated sulfated steroids: structure/activity studies.

PubMed

Richmond, Victoria; Murray, Ana P; Maier, Marta S

2013-11-01

Disulfated and trisulfated steroids have been synthesized from cholesterol and their acetylcholinesterase inhibitory activity has been evaluated. In our studies we have found that the activity was not only dependent on the location of the sulfate groups but on their configurations. 2β,3α,6α-trihydroxy-5α-cholestan-6-one trisulfate (18) was the most active steroid with an IC50 value of 15.48 μM comparable to that of 2β,3α-dihydroxy-5α-cholestan-6-one disulfate (1). Both compounds were found to be less active than the reference compound eserine. The butyrylcholinesterase activity of 1 and 18 was one magnitude lower than that against acetylcholinesterase revealing a selective inhibitor profile. Copyright © 2013 Elsevier Inc. All rights reserved.

Multitarget-Directed Ligands Combining Cholinesterase and Monoamine Oxidase Inhibition with Histamine H3 R Antagonism for Neurodegenerative Diseases.

PubMed

Bautista-Aguilera, Óscar M; Hagenow, Stefanie; Palomino-Antolin, Alejandra; Farré-Alins, Víctor; Ismaili, Lhassane; Joffrin, Pierre-Louis; Jimeno, María L; Soukup, Ondřej; Janočková, Jana; Kalinowsky, Lena; Proschak, Ewgenij; Iriepa, Isabel; Moraleda, Ignacio; Schwed, Johannes S; Romero Martínez, Alejandro; López-Muñoz, Francisco; Chioua, Mourad; Egea, Javier; Ramsay, Rona R; Marco-Contelles, José; Stark, Holger

2017-10-02

The therapy of complex neurodegenerative diseases requires the development of multitarget-directed drugs (MTDs). Novel indole derivatives with inhibitory activity towards acetyl/butyrylcholinesterases and monoamine oxidases A/B as well as the histamine H 3 receptor (H3R) were obtained by optimization of the neuroprotectant ASS234 by incorporating generally accepted H3R pharmacophore motifs. These small-molecule hits demonstrated balanced activities at the targets, mostly in the nanomolar concentration range. Additional in vitro studies showed antioxidative neuroprotective effects as well as the ability to penetrate the blood-brain barrier. With this promising in vitro profile, contilisant (at 1 mg kg -1 i.p.) also significantly improved lipopolysaccharide-induced cognitive deficits. © 2017 Wiley-VCH Verlag GmbH & Co. KGaA, Weinheim.

New (benz)imidazolopyridino tacrines as nonhepatotoxic, cholinesterase inhibitors for Alzheimer disease.

PubMed

Boulebd, Houssem; Ismaili, Lhassane; Martin, Helene; Bonet, Alexandre; Chioua, Mourad; Marco Contelles, José; Belfaitah, Ali

2017-05-01

Due to the multifactorial nature of Alzheimer's disease, there is an urgent search for new more efficient, multitarget-directed drugs. This paper describes the synthesis, antioxidant and in vitro biological evaluation of ten (benz)imidazopyridino tacrines (7-16), showing less toxicity than tacrine at high doses, and potent cholinesterase inhibitory capacity, in the low micromolar range. Among them, compound 10 is a nonhepatotoxic tacrine at 1000 mM, showing moderate, but totally selective electric eel acetylcholinesterase inhibition, whereas molecule 16 is twofold less toxic than tacrine at 1000 μM, showing moderate and almost equipotent inhibition for electric eel acetylcholinesterase and equine butyrylcholinesterase. (Benz)imidazopyridino tacrines (7-16) have been identified as a new and promising type of tacrines for the potential treatment of Alzheimer's disease.

Cholinesterase inhibitors from the roots of Harpagophytum procumbens.

PubMed

Bae, Yoon Ho; Cuong, To Dao; Hung, Tran Manh; Kim, Jeong Ah; Woo, Mi Hee; Byeon, Jeong Su; Choi, Jae Sue; Min, Byung Sun

2014-01-01

Inhibition of cholinesterase has been proposed to be a therapeutic target for the treatment of Alzheimer's diseases. In our preliminary screening study on the acetylcholinesterase (AChE) inhibitory activity, an ethyl acetate soluble fraction of the roots of Harpagophytum procumbens (Pedaliaceae) was found to inhibit AChE activity at the concentration of 100 μg/mL. Ten compounds (1-10) were isolated from the active fraction and evaluated for their inhibitory effect on AChE and butyrylcholinesterase (BChE). Among the isolates, verbascosides (5, 6, and 8) containing a caffeoyl and a 3,4-dihydroxyphenethyl groups in their structures, showed effective AChE inhibitory activity and also possessed BChE inhibitory activity. The findings suggest that verbascoside derivatives may be partially related to the anti-Alzheimer effect of this medicinal plant.

Cholinesterase inhibitors from Cleistocalyx operculatus buds.

PubMed

Min, Byung Sun; Cuong, To Dao; Lee, Joo-Sang; Shin, Beom-Soo; Woo, Mi Hee; Hung, Tran Manh

2010-10-01

Five flavonoids, myricetin-3'-methylether 3-O-β-D: -galactopyranoside (1), myricetin-3',5'-dimethylether 3-O-β-D: -galactopyranoside (2), quercetin (3), kaempferol (4), and tamarixetin (5) were isolated from the buds of Cleistocalyx operculatus (Myrtaceae). The chemical structures of these compounds were determined on the basis of spectroscopic analyses, including 2D NMR. Their anti-Alzheimer effects were evaluated via acetylcholinesterase (AChE) and butyrylcholinesterase (BChE) inhibitory activity assays. All five compounds 1-5 showed potential inhibitory activities against AChE with IC(50) values of 19.9, 37.8, 25.9, 30.4 and 22.3 μM, respectively, while compounds 1, 3, 4 and 5 also possessed BChE inhibitory activity with IC(50) values of 152.5, 177.8, 62.5, and 160.6 μM, respectively.

Cholinesterase inhibitors from botanicals

PubMed Central

Ahmed, Faiyaz; Ghalib, Raza Murad; Sasikala, P.; Ahmed, K. K. Mueen

2013-01-01

Alzheimer's disease (AD) is a progressive neurodegenerative disease, wherein a progressive loss of cholinergic synapses occurs in hippocampus and neocortex. Decreased concentration of the neurotransmitter, acetylcholine (ACh), appears to be critical element in the development of dementia, and the most appropriate therapeutic approach to treat AD and other form of dementia is to restore acetylcholine levels by inhibiting both major form of cholinesterase: Acetylcholinesterase (AChE) and butyrylcholinesterase (BChE). Consequently, researches have focused their attention towards finding cholinesterase inhibitors from natural products. A large number of such inhibitors have been isolated from medicinal plants. This review presents a comprehensive account of the advances in field of cholinesterase inhibitor phytoconstituents. The structures of some important phytoconstituents (collected through www.Chemspider.com) are also presented and the scope for future research is discussed. PMID:24347920

Mechanism of inhibition of cholinesterases by Huperzine A. (Reannouncement with new availability information)

DOE Office of Scientific and Technical Information (OSTI.GOV)

Ashani, Y.; Peggins, J.O.; Doctor, B.P.

1992-04-30

Huperzine A, an alkaloid isolated from Huperzia serrata was found to reversibly inhibit acetylcholinesterases (EC 3.1.7) and (EC 3.1.1.8) with i 3.1 on- and off-rates that depend on both the type and the source of enzyme. Long incubation of high concentrations of purified (1-8 PM) with huperzine-A did not show any chemical modification of huperzine-A. A low dissociation constant K sub 1 was obtained for mammalian acetylcholinesterase-huperzine (20-40 nM) compared to mammalian butyrylcholinesterase-huperzine (20-40 microns.) This indicates that the thermodynamic stability of huperzine-cholinesterase complex may depend on the number and type of aromatic amino acid residues in the catalytic pocketmore » region of the cholinesterase molecule.« less

Cholinesterase activity in black-crowned night-herons exposed to fenthion-treated water

USGS Publications Warehouse

Smith, G.J.; Spann, J.W.; Hill, E.F.

1986-01-01

Fenthion, (O,O-Dimethyl O-(3-methyl-4-(methylthio)phenyl) phosphorothioate), a widely used mosquito control agent, has caused wildlife mortality. To simulate a shallow wetland environment, an exposure chamber was used containing water treated with fenthion at 1 and 10 times the field application rate of 112 g active ingredient (AI)/ha. This system permitted an evaluation of exposure routes and the effects of fenthion in a representative species of wading bird, the black-crowned night-heron (Nycticorax nycticorax). The results suggested that herons received only a dermal exposure, and that their brain acetylcholinesterase activity was not significantly inhibited. In contrast, however, plasma butyrylcholinesterase activity was inhibited, suggesting the herons were exposed to the insecticide. The application rates and types of exposures were not life-threatening in this species.

Regulated Extracellular Choline Acetyltransferase Activity— The Plausible Missing Link of the Distant Action of Acetylcholine in the Cholinergic Anti-Inflammatory Pathway

PubMed Central

Aeinehband, Shahin; Behbahani, Homira; Grandien, Alf; Nilsson, Bo; Ekdahl, Kristina N.; Lindblom, Rickard P. F.; Piehl, Fredrik; Darreh-Shori, Taher

2013-01-01

Acetylcholine (ACh), the classical neurotransmitter, also affects a variety of nonexcitable cells, such as endothelia, microglia, astrocytes and lymphocytes in both the nervous system and secondary lymphoid organs. Most of these cells are very distant from cholinergic synapses. The action of ACh on these distant cells is unlikely to occur through diffusion, given that ACh is very short-lived in the presence of acetylcholinesterase (AChE) and butyrylcholinesterase (BuChE), two extremely efficient ACh-degrading enzymes abundantly present in extracellular fluids. In this study, we show compelling evidence for presence of a high concentration and activity of the ACh-synthesizing enzyme, choline-acetyltransferase (ChAT) in human cerebrospinal fluid (CSF) and plasma. We show that ChAT levels are physiologically balanced to the levels of its counteracting enzymes, AChE and BuChE in the human plasma and CSF. Equilibrium analyses show that soluble ChAT maintains a steady-state ACh level in the presence of physiological levels of fully active ACh-degrading enzymes. We show that ChAT is secreted by cultured human-brain astrocytes, and that activated spleen lymphocytes release ChAT itself rather than ACh. We further report differential CSF levels of ChAT in relation to Alzheimer’s disease risk genotypes, as well as in patients with multiple sclerosis, a chronic neuroinflammatory disease, compared to controls. Interestingly, soluble CSF ChAT levels show strong correlation with soluble complement factor levels, supporting a role in inflammatory regulation. This study provides a plausible explanation for the long-distance action of ACh through continuous renewal of ACh in extracellular fluids by the soluble ChAT and thereby maintenance of steady-state equilibrium between hydrolysis and synthesis of this ubiquitous cholinergic signal substance in the brain and peripheral compartments. These findings may have important implications for the role of cholinergic signaling in states of inflammation in general and in neurodegenerative disease, such as Alzheimer’s disease and multiple sclerosis in particular. PMID:23840379

Modification of pharmacokinetic and abuse-related effects of cocaine by human-derived cocaine hydrolase in monkeys.

PubMed

Schindler, Charles W; Justinova, Zuzana; Lafleur, David; Woods, Doug; Roschke, Viktor; Hallak, Hussein; Sklair-Tavron, Liora; Redhi, Godfrey H; Yasar, Sevil; Bergman, Jack; Goldberg, Steven R

2013-01-01

Although substantial research effort has focused on developing pharmacological treatments for cocaine abuse, no effective medications have been developed. Recent studies show that enzymes that metabolize cocaine in the periphery, forestalling its entry into the brain, can prevent cocaine toxicity and its behavioral effects in rodents. Here we report on effects of one such enzyme (Albu-CocH) on the pharmacokinetic and behavioral effects of cocaine in squirrel monkeys. Albu-CocH was developed from successive mutations of human butyrylcholinesterase (BChE) and has 1000-fold greater catalytic activity against cocaine than naturally occurring BChE. Pharmacokinetic studies showed that Albu-CocH (5 mg/kg) had a half-life of 56.6 hours in squirrel monkeys. In these studies, plasma levels of cocaine following i.v. 1 mg/kg cocaine were reduced 2 hours after administration of Albu-CocH, whereas plasma levels of the cocaine metabolite ecgonine methyl ester were increased. These effects were still evident 72 hours following Albu-CocH administration. In behavioral experiments in monkeys, pre-treatment with 5 mg/kg Albu-CocH dramatically decreased self-administration of a reinforcing dose of i.v. cocaine (30 µg/kg/injection) for over 24 hours. Pre-treatment with 5 mg/kg Albu-CocH also attenuated the reinstatement of extinguished cocaine self-administration by an i.v. priming injection of cocaine (0.1 or 0.3 mg/kg) and, in separate studies, attenuated the discriminative-stimulus effects of cocaine. The ability of Albu-CocH to attenuate the abuse-related effects of cocaine in squirrel monkeys indicates that further investigation of BChE mutants as potential treatment for cocaine abuse and toxicity is warranted. Published 2012. This article is a U.S. Government work and is in the public domain in the USA.

Human serum cholinesterase from liver pathological samples exhibit highly elevated aryl acylamidase activity.

PubMed

Boopathy, Rathanam; Rajesh, Ramanna Valmiki; Darvesh, Sultan; Layer, Paul G

2007-05-01

Although aspartate aminotransferase (AST) and gamma-glutamyltransferase (gamma GT) enzymes are widely used as markers for liver disorders, the ubiquitous enzyme butyrylcholinesterase (BChE), synthesized in liver is also used as marker in the assessment of liver pathophysiology. This BChE enzyme in addition to its esterase activity has yet another enzymatic function designated as aryl acylamidase (AAA) activity. It is determined in in vitro based on the hydrolysis of the synthetic substrate o-nitroacetanilide. In the present study, human serum cholinesterase (BChE) activity was studied with respect to its AAA activity on the BChE protein (AAA(BChE)) in patients with liver disorders. AST and gamma GT values were taken into account in this study as known markers for liver disorders. Blood samples were grouped into 3 based on esterase activity associated with BChE protein. They are normal, low, and very low BChE activity but with markedly increased AST and gamma GT levels. These samples were tested for their respective AAA function. Association of AAA with BChE from samples was proved using BChE monoclonal antibody precipitation experiment. The absolute levels of AAA were increased as BChE activity decreased while deviating from normal samples and such deviation was directly proportional to the severity of the liver disorder. Differences between these groups became prominent after determining the ratios of AAA(BChE) to BChE activities. Samples showing very high AAA(BChE) to BChE ratio were also showing high to very high gamma GT values. These findings establish AAA(BChE) as an independently regulated enzymatic activity on BChE especially in liver disorders. Moreover, since neither the low esterase activity of BChE by itself nor increased levels of AST/gamma GT are sufficient pathological indicators, this pilot study merits replication with large sample numbers.

Acylated ghrelin concentrations are markedly decreased during pregnancy in mothers with and without gestational diabetes: relationship with cholinesterase.

PubMed

Tham, Elaine; Liu, Jianhua; Innis, Sheila; Thompson, David; Gaylinn, Bruce D; Bogarin, Roberto; Haim, Alon; Thorner, Michael O; Chanoine, Jean-Pierre

2009-05-01

Acylated (octanoylated) ghrelin stimulates food intake and growth hormone secretion and is deacylated into desacyl ghrelin by butyrylcholinesterase. Acylated and desacyl ghrelin both promote adipogenesis. Ghrelin concentrations decrease with hyperglycemia and hyperinsulinism. We hypothesized that 1) acylated ghrelin increases during pregnancy, contributing positively to energy balance, but is lower in women with gestational diabetes and 2) butyrylcholinesterase activity is inversely correlated with acylated ghrelin concentrations. In a first group of subjects, using two-site sandwich ghrelin assays that specifically detect full-length forms, we investigated women with and without gestational diabetes (n = 14/group) during pregnancy and after delivery. We examined whether changes in ghrelin during a test meal were correlated with changes in pituitary growth hormone [assessed through calculation of the area under the curve (AUC) during the test meal]. In postpartum subjects, the percent of total ghrelin that is acylated was four to five times higher than previously observed using single antibody assays. During pregnancy, acylated ghrelin concentrations (mean +/- SE) were lower compared with the postpartum period throughout the meal (AUC 1.2 +/- 0.2 vs. 10.2 +/- 1.9 ng.ml(-1).90 min(-1), P < 0.001). In the postpartum, acylated ghrelin and growth hormone were positively correlated (r = 0.50, P = 0.007). Desacyl (but not acylated) ghrelin was increased in subjects with gestational diabetes during and after pregnancy (AUC 15.4 +/- 1.9 vs. 8.6 +/- 1.2 ng.ml(-1).90 min(-1), P = 0.005). In a second group of subjects (n = 13), acylated ghrelin was similarly suppressed during pregnancy. Circulating octanoate concentrations (3.1 +/- 0.5 vs. 4.5 +/- 0.6 microg/ml, P = 0.029) and cholinesterase activity (705 +/- 33 vs. 1,013 +/- 56 U/ml, P < 0.001) were lower during pregnancy compared with the postpartum period. In conclusion, acylated ghrelin markedly decreases during pregnancy, likely because of a decrease in the acylation process. Desacyl ghrelin increases in gestational diabetes, possibly reflecting resistance to the inhibitory effect of insulin on ghrelin secretion.

Acylated ghrelin concentrations are markedly decreased during pregnancy in mothers with and without gestational diabetes: relationship with cholinesterase

PubMed Central

Tham, Elaine; Liu, Jianhua; Innis, Sheila; Thompson, David; Gaylinn, Bruce D.; Bogarin, Roberto; Haim, Alon; Thorner, Michael O.; Chanoine, Jean-Pierre

2009-01-01

Acylated (octanoylated) ghrelin stimulates food intake and growth hormone secretion and is deacylated into desacyl ghrelin by butyrylcholinesterase. Acylated and desacyl ghrelin both promote adipogenesis. Ghrelin concentrations decrease with hyperglycemia and hyperinsulinism. We hypothesized that 1) acylated ghrelin increases during pregnancy, contributing positively to energy balance, but is lower in women with gestational diabetes and 2) butyrylcholinesterase activity is inversely correlated with acylated ghrelin concentrations. In a first group of subjects, using two-site sandwich ghrelin assays that specifically detect full-length forms, we investigated women with and without gestational diabetes (n = 14/group) during pregnancy and after delivery. We examined whether changes in ghrelin during a test meal were correlated with changes in pituitary growth hormone [assessed through calculation of the area under the curve (AUC) during the test meal]. In postpartum subjects, the percent of total ghrelin that is acylated was four to five times higher than previously observed using single antibody assays. During pregnancy, acylated ghrelin concentrations (mean ± SE) were lower compared with the postpartum period throughout the meal (AUC 1.2 ± 0.2 vs. 10.2 ± 1.9 ng·ml−1·90 min−1, P < 0.001). In the postpartum, acylated ghrelin and growth hormone were positively correlated (r = 0.50, P = 0.007). Desacyl (but not acylated) ghrelin was increased in subjects with gestational diabetes during and after pregnancy (AUC 15.4 ± 1.9 vs. 8.6 ± 1.2 ng·ml−1·90 min−1, P = 0.005). In a second group of subjects (n = 13), acylated ghrelin was similarly suppressed during pregnancy. Circulating octanoate concentrations (3.1 ± 0.5 vs. 4.5 ± 0.6 μg/ml, P = 0.029) and cholinesterase activity (705 ± 33 vs. 1,013 ± 56 U/ml, P < 0.001) were lower during pregnancy compared with the postpartum period. In conclusion, acylated ghrelin markedly decreases during pregnancy, likely because of a decrease in the acylation process. Desacyl ghrelin increases in gestational diabetes, possibly reflecting resistance to the inhibitory effect of insulin on ghrelin secretion. PMID:19240252

Combined in Vitro and in Silico Studies for the Anticholinesterase Activity and Pharmacokinetics of Coumarinyl Thiazoles and Oxadiazoles

PubMed Central

Ibrar, Aliya; Khan, Ajmal; Ali, Majid; Sarwar, Rizwana; Mehsud, Saifullah; Farooq, Umar; Halimi, Syed M. A.; Khan, Imtiaz; Al-Harrasi, Ahmed

2018-01-01

In a continuation of our previous work for the exploration of novel enzyme inhibitors, two new coumarin-thiazole 6(a–o) and coumarin-oxadiazole 11(a–h) hybrids have been designed and synthesized. All the compounds were characterized by 1H- and 13C-NMR spectroscopy and elemental analysis. New hybrid analogs were evaluated against acetylcholinesterase (AChE) and butyrylcholinesterase (BuChE) in order to know their potential for the prevention of Alzheimer's disease (AD). In coumarinyl thiazole series, compound 6b was found as the most active member against AChE having IC50 value of 0.87 ± 0.09 μM, while the compound 6j revealed the same efficacy against BuChE with an IC50 value of 11.01 ± 3.37 μM. In case of coumarinyl oxadiazole series, 11a was turned out to be the lead candidate against AChE with an IC50 value of 6.07 ± 0.23 μM, whereas compound 11e was found significantly active against BuChE with an IC50 value of 0.15 ± 0.09 μM. To realize the binding interaction of these compounds with AChE and BuChE, the molecular docking studies were performed. Compounds from coumarinyl thiazole series with potent AChE activity (6b, 6h, 6i, and 6k) were found to interact with AChE in the active site with MOE score of −10.19, −9.97, −9.68, and −11.03 Kcal.mol−1, respectively. The major interactions include hydrogen bonding, π-π stacking with aromatic residues, and interaction through water bridging. The docking studies of coumarinyl oxadiazole derivatives 11(a–h) suggested that the compounds with high anti-butyrylcholinesterase activity (11e, 11a, and 11b) provided MOE score of −9.9, −7.4, and −8.2 Kcal.mol−1, respectively, with the active site of BuChE building π-π stacking with Trp82 and water bridged interaction. PMID:29632858

Blood and bronchoalveolar lavage fluid acetylcholinesterase levels following microinstillation inhalation exposure to sarin in Guinea pigs.

PubMed

Che, Magnus M; Conti, Michele; Boylan, Megan; Sciuto, Alfred M; Gordon, Richard K; Nambiar, Madhusoodana P

2008-07-01

We determined acetylcholinesterase (AChE) and butyrylcholinesterase (BChE) inhibition in the bronchoalveolar lavage fluid (BALF) following inhalation exposure to chemical threat nerve agent (CTNA) sarin. Age- and weight-matched male guinea pigs were exposed to five different doses of sarin (169.3, 338.7, 508, 677.4, and 846.5 mg/m(3)) using a microinstillation inhalation exposure technique for 4 min. The technique involves aerosolization of the agent in the trachea using a microcatheter with a center hole that delivers the agent and multiple peripheral holes that pumps air to aerosolize the agent at the tip. Animals exposed to higher doses of sarin occasionally developed seizures and succumbed to death within 15 min after exposure. The LCt(50) for sarin using the microinstillation technique was determined to be close to 677.4 mg/m(3). Ear blood AChE activity showed a dose-dependent inhibition at 15 min postexposure. The inhibition of blood AChE remained constant over 35 and 55 min after sarin exposure indicating that there was no lung depot effect. Cardiac blood AChE and butyrylcholinesterase (BChE) activity in surviving animals euthanized at 24 h postexposure showed a dose-dependent inhibition with an inhibition of 60% at 677.4 and 846.5 mg/m(3) sarin exposure. AChE and BChE activity in bronchoalveolar lavage fluid (BALF) showed a slight increase at 338.7 to 677.4 mg/m(3) sarin exposure but a marginal inhibition at 169.3 mg/m(3). In contrast, the AChE protein levels determined by immunoblotting showed an increase at 169.3 mg/m(3) in the BALF. The BALF protein level, a biomarker of lung injury, was increased maximally at 338.7 mg/m(3) and that increase was dropped with an increase in the dose of sarin. The BALF protein levels correlated with the AChE and BChE activity. These data suggest that sarin microinstillation inhalation exposure results in respiratory toxicity and lung injury characterized by changes in lavage AChE, BChE, and protein levels.

Determinants of Butyrylcholinesterase Inhibition Among Agricultural Pesticide Handlers in Washington State: An Update

PubMed Central

Krenz, Jennifer E.; Hofmann, Jonathan N.; Smith, Theresa R.; Cunningham, Rad N.; Fenske, Richard A.; Simpson, Christopher D.; Keifer, Matthew

2015-01-01

Objectives: Organophosphate (OP) and N-methyl-carbamate (CB) insecticides are used widely in agriculture to manage insect pests of economic importance. Agricultural workers are more likely to suffer exposure because of the widespread use of OP/CBs in agriculture, and pesticide-related illnesses among handlers may be more severe when compared to other farm workers. The goal of this study was to identify occupational and personal characteristics associated with butyrylcholinesterase (BuChE) inhibition in participants recruited from the Washington State Cholinesterase Monitoring Program from 2006 to 2011. Methods: We conducted a longitudinal study among agricultural pesticide handlers in Washington State during the OP/CB spray season (March–July) over a 6-year period (2006–2011). Linear mixed effects regression models were used to evaluate BuChE inhibition in relation to self-reported occupational and personal characteristics. Results: Relative to pre-season baseline levels, the mean decrease in BuChE activity during the OP/CB spray season over all years of the study period was 3.77% (P < 0.001). Greater BuChE inhibition was observed among handlers who reported using multiple OP/CBs (β = −2.70, P = 0.045), mixed or loaded OP/CBs (β = −3.97, P = 0.002), did not store personal protective equipment (PPE) in a locker at work (β = −3.4, P = 0.014), or did not wear chemical-resistant boots (β = −16.6, P < 0.001). Discussion and Conclusions: The Washington State Cholinesterase Monitoring Program has provided a valuable opportunity to evaluate potential sources of OP/CB exposure among agricultural pesticide handlers. Several previously reported associations were confirmed in the current analysis, which included a larger number of pesticide handlers enrolled over a longer time period. The use of multiple OP/CBs and mixing/loading activities were significant risk factors, and the use of chemical-resistant boots and lockers for PPE storage were protective factors. Our findings point toward logical interventions to reduce exposure such as the implementation of engineering controls for mixing/loading activities, requirements for appropriate footwear, and the regular use of lockers for PPE storage. PMID:25261454

Determinants of butyrylcholinesterase inhibition among agricultural pesticide handlers in Washington State: an update.

PubMed

Krenz, Jennifer E; Hofmann, Jonathan N; Smith, Theresa R; Cunningham, Rad N; Fenske, Richard A; Simpson, Christopher D; Keifer, Matthew

2015-01-01

Organophosphate (OP) and N-methyl-carbamate (CB) insecticides are used widely in agriculture to manage insect pests of economic importance. Agricultural workers are more likely to suffer exposure because of the widespread use of OP/CBs in agriculture, and pesticide-related illnesses among handlers may be more severe when compared to other farm workers. The goal of this study was to identify occupational and personal characteristics associated with butyrylcholinesterase (BuChE) inhibition in participants recruited from the Washington State Cholinesterase Monitoring Program from 2006 to 2011. We conducted a longitudinal study among agricultural pesticide handlers in Washington State during the OP/CB spray season (March-July) over a 6-year period (2006-2011). Linear mixed effects regression models were used to evaluate BuChE inhibition in relation to self-reported occupational and personal characteristics. Relative to pre-season baseline levels, the mean decrease in BuChE activity during the OP/CB spray season over all years of the study period was 3.77% (P < 0.001). Greater BuChE inhibition was observed among handlers who reported using multiple OP/CBs (β = -2.70, P = 0.045), mixed or loaded OP/CBs (β = -3.97, P = 0.002), did not store personal protective equipment (PPE) in a locker at work (β = -3.4, P = 0.014), or did not wear chemical-resistant boots (β = -16.6, P < 0.001). The Washington State Cholinesterase Monitoring Program has provided a valuable opportunity to evaluate potential sources of OP/CB exposure among agricultural pesticide handlers. Several previously reported associations were confirmed in the current analysis, which included a larger number of pesticide handlers enrolled over a longer time period. The use of multiple OP/CBs and mixing/loading activities were significant risk factors, and the use of chemical-resistant boots and lockers for PPE storage were protective factors. Our findings point toward logical interventions to reduce exposure such as the implementation of engineering controls for mixing/loading activities, requirements for appropriate footwear, and the regular use of lockers for PPE storage. © The Author 2014. Published by Oxford University Press on behalf of the British Occupational Hygiene Society.

Combined in vitro and in silico studies for the anticholinesterase activity and pharmacokinetics of coumarinyl thiazoles and oxadiazoles

NASA Astrophysics Data System (ADS)

Ibrar, Aliya; Khan, Ajmal; Ali, Majid; Sarwar, Rizwana; Mehsud, Saifullah; Farooq, Umar; Halimi, Syed M. A.; Khan, Imtiaz; Al-Harrasi, Ahmed

2018-03-01

In a continuation of our previous work for the exploration of novel enzyme inhibitors, two new coumarin-thiazole 6(a–o) and coumarin-oxadiazole 11(a–h) hybrids have been designed and synthesized. All the compounds were characterized by 1H- and 13C-NMR spectroscopy and elemental analysis. New hybrid analogues were evaluated against acetylcholinesterase (AChE) and butyrylcholinesterase (BuChE) in order to know their potential for the prevention of Alzheimer’s disease (AD). In coumarinyl thiazole series, compound 6b was found as the most active member against AChE having IC50 value of 0.87 ± 0.09 µM, while the compound 6j revealed the same efficacy against BuChE with an IC50 value of 11.01 ± 3.37 µM. In case of coumarinyl oxadiazole series, 11a was turned out to be the lead candidate against AChE with an IC50 value of 6.07 ± 0.23 µM, whereas compound 11e was found significantly active against BuChE with an IC50 value of 0.15 ± 0.09 µM. To realize the binding interaction of these compounds with AChE and BuChE, the molecular docking studies were performed. Compounds from coumarinyl thiazole series with potent AChE activity (6b, 6h, 6i and 6k) were found to interact with AChE in the active site with MOE score of ‒10.19, ‒9.97, ‒9.68, and ‒11.03 Kcal.mol‒1, respectively. The major interactions include hydrogen bonding, π-π stacking with aromatic residues, and interaction through water bridging. The docking studies of coumarinyl oxadiazole derivatives 11(a-h) suggested that the compounds with high anti-butyrylcholinesterase activity (11e, 11a and 11b) provided MOE score of ‒9.9, ‒7.4 and ‒8.2 Kcal.mol‒1 respectively, with the active site of BuChE building π-π stacking with Trp82 and water bridged interaction.

Effects of motor patterns on water-soluble and membrane proteins and cholinesterase activity in subcellular fractions of rat brain tissue

NASA Technical Reports Server (NTRS)

Pevzner, L. Z.; Venkov, L.; Cheresharov, L.

1980-01-01

Albino rats were kept for a year under conditions of daily motor load or constant hypokinesia. An increase in motor activity results in a rise in the acetylcholinesterase activity determined in the synaptosomal and purified mitochondrial fractions while hypokinesia induces a pronounced decrease in this enzyme activity. The butyrylcholinesterase activity somewhat decreases in the synaptosomal fraction after hypokinesia but does not change under the motor load pattern. Motor load causes an increase in the amount of synaptosomal water-soluble proteins possessing an intermediate electrophoretic mobility and seem to correspond to the brain-specific protein 14-3-2. In the synaptosomal fraction the amount of membrane proteins with a low electrophoretic mobility and with the cholinesterase activity rises. Hypokinesia, on the contrary, decreases the amount of these membrane proteins.

Anti-Alzheimers activity and molecular mechanism of albumin-derived peptides against AChE and BChE.

PubMed

Yu, Zhipeng; Wu, Sijia; Zhao, Wenzhu; Ding, Long; Fan, Yue; Shiuan, David; Liu, Jingbo; Chen, Feng

2018-02-21

Alzheimer's disease (AD) is a global health issue affecting millions of elderly people worldwide. The aim of the present study was to identify novel anti-AD peptides isolated from albumin. Anti-AD activities of the peptides were evaluated via inhibitory activities on acetylcholinesterase (AChE) and butyrylcholinesterase (BChE). Furthermore, the potential molecular mechanisms of the KLPGF/AChE were investigated by CDOCKER of Discovery studio 2017. The results revealed that peptide KLPGF could effectively inhibit AChE with an inhibition rate of 61.23% at a concentration of 50 μg mL -1 . In addition, the peptide KLPGF came in contact with acylation sites and peripheral anion sites of AChE. The present study demonstrates that the peptide KLPGF could become a potential functional food intervention in AD.

[Design, synthesis and evaluation of bis-nicotine derivatives as inhibitors of cholinesterases and beta-amyloid aggregation].

PubMed

Luo, Wen; Zhao, Yong-mei; Tian, Run-guo; Su, Ya-bin; Hong, Chen

2013-11-01

A novel series of bis-nicotine derivatives (3a-3i) were designed, synthesized and evaluated as bivalent anti-Alzheimer's disease agents. The pharmacological results indicated that compounds 3e-3i inhibited both acetylcholinesterase (AChE) and butyrylcholinesterase (BChE) in the micromolar range (IC50, 2.28-117.86 micromol x L(-1) for AChE and 1.67-125 micromol x L(-1) for BChE), which was at the same potency as rivastigmine. A Lineweaver-Burk plot and molecular modeling study showed that these derivatives targeted both the catalytic active site (CAS) and the peripheral anionic site (PAS) of AChE. Besides, these compounds could significantly inhibit the self-induced Abeta aggregation with inhibition activity (11.85%-62.14%) at the concentration of 20 micromol x L(-1).

Cholinesterase inhibitors: a patent review (2007 - 2011).

PubMed

de los Ríos, Cristóbal

2012-08-01

Cholinesterase inhibitors participate in the maintenance of the levels of the neurotransmitter acetylcholine by inhibiting the enzymes implicated in its degradation, namely, butyrylcholinesterase and acetylcholinesterase. This pharmacological action has an important role in several diseases, including neurodegenerative diseases such as Alzheimer's. This article reviews recent advances in the development of cholinesterase enzyme inhibitors, covering the development of new chemical entities, new pharmaceutical formulations with known inhibitors or treatments in combination with other drug families. The development of cholinesterase inhibitors has to face several issues, including the fact that the principal indication for these drugs, Alzheimer's disease, is not currently believed to derivate from a cholinergic deficiency, although most of the drugs clinically used for these disease are cholinesterase inhibitors. Moreover, the adverse effects found when administering cholinesterase inhibitors limit their use in other diseases, such as gastrointestinal diseases, glaucoma, or analgesia.

Design, synthesis, molecular modeling and anticholinesterase activity of benzylidene-benzofuran-3-ones containing cyclic amine side chain.

PubMed

Mehrabi, Farzad; Pourshojaei, Yaghoub; Moradi, Alireza; Sharifzadeh, Mohammad; Khosravani, Leila; Sabourian, Reyhaneh; Rahmani-Nezhad, Samira; Mohammadi-Khanaposhtani, Maryam; Mahdavi, Mohammad; Asadipour, Ali; Rahimi, Hamid Reza; Moghimi, Setareh; Foroumadi, Alireza

2017-05-01

A series of 2-benzylidene-benzofuran-3-ones were designed from the structures of Ebselen analogs and aurone derivatives and synthesized in good yields. The target compounds were prepared by the condensation reaction between appropriate benzofuranones with amino alkoxy aldehydes and evaluated as cholinesterase inhibitors by Ellman's method. The in vitro anti-acetylcholinesterase (AChE)/butyrylcholinesterase activities of the synthesized compounds revealed that 7e (IC 50 = 0.045 μM) is the most active compound against AChE. Furthermore, the docking study confirmed the results obtained through in vitro experiments and predicted the possible binding conformation. The anticholinesterase activities of benzylidene-benzofurane-3-ones as aurone analogs revealed that the compounds bearing piperidinylethoxy residue showed better activities against AChE, introducing these compounds for further drug discovery developments. [Formula: see text].

Exposure to triaryl phosphates: metabolism and biomarkers of exposure.

PubMed

Furlong, Clement E

2011-01-01

The leakage of tricresyl phosphate-containing engine lubricants into aircraft cabin air, either from worn or defective engine seals or under normal operating conditions, is a serious concern for both the health and safety of the cabin occupants, since the oil contains one to five percent tricresyl phosphate (TCP) esters, known neurotoxins. The exposure of pilots is a particular concern since their impairment can affect their safe operation of the aircraft. Mass spectrometric (MS)-based protocols for documenting exposures of individuals are described that entail a rapid purification of the TCP-modified plasma enzyme butyrylcholinesterase (BChE). Following protease digestion of BChE, the modified active site peptide is characterized by MS analysis. Approaches for identifying safer engine oil additives are also described. Some general comments regarding the necessity of improving the quality and safety of the cabin air supply are presented.

Tritium labeling of a powerful methylphosphonate inhibitor of cholinesterase: synthesis and biological applications

DOE Office of Scientific and Technical Information (OSTI.GOV)

Balan, A.; Barness, I.; Simon, G.

1988-02-15

7-(Methylethoxy phosphinyloxy)-1-methyl-quinolinium iodide (MEPQ), a powerful anti-cholinesterase methylphosphonate ester, was labeled with tritium (9 Ci/mmol) at the methylphosphonyl moiety (TCH2P(O)(OR)X) by an iodine-tritium replacement reaction. Kinetic measurements of the rate of inhibition of acetylcholinesterase (AChE) by (/sup 3/H)MEPQ and its rate of hydrolysis in alkaline solution confirmed the identity of (/sup 3/H)MEPQ with authentic MEPQ, which was prepared by the same reaction sequences. Gel-filtration experiments verified the radiospecificity of (/sup 3/H)MEPQ. In vitro radiolabeling of both AChE and butyrylcholinesterase along with the whole-body autoradiography of (/sup 3/H)MEPQ-treated mice suggests that (/sup 3/H)MEPQ is a convenient marker for studying biological systemsmore » containing these esterases.« less

Synthesis of dibenzodioxazocines and their effects on cholinesterases and muscarinic cholinergic receptors.

PubMed

Gaál, J; Batke, J; Borsodi, A; Rózsa, L; Somogyi, G

1989-01-01

A new family of tricyclic compounds, the dibenzodioxazocines were synthesized. These compounds were the following: 2-chloro-12-(2-piperidino-ethyl)-dibenzo d,g 1,3,6 dioxazocine hydrochloride: EGYT-2347, 2-chloro-12-(3-dimethylamino-2-methyl-propyl)-dibenzo [d,g] [1,3,6]-dibenzodioxazocine hydrochloride: EGYT-2509, 2-chloro-12-(3-dimethylamino-propyl)-dibenzo [d,g] [1,3,6] dioxazocine-maleate: EGYT-2474 and 2-chloro-12-2-(4-methyl-piperazino)-ethyl-dibenzo [d,g] [1,3,6]-dioxazocine-dihydrochloride: EGYT-2541. These compounds are inhibitors of both butyryl- and acetylcholinesterase to and they exhibited relatively good anticholinergic properties in receptor binding experiments. The most selective inhibitor of butyrylcholinesterase is the compound EGYT-2347 (Ki = 1.5 x 10(-7) M) which strongly binds to rat brain muscarinic cholinergic receptor (KD = 4.1 x 10(-8) M).

Current concepts on selected plant secondary metabolites with promising inhibitory effects against enzymes linked to Alzheimer's disease.

PubMed

Orhan, I Erdogan

2012-01-01

Alzheimer's disease (AD) has become one of the deadliest diseases for human beings with special incidence in elderly population. It is a progressive neurodegenerative disease and the most prevalent cause of dementia. The neuropathology of AD has not been fully elucidated yet, however, cholinergic hypothesis is the most accepted theory nowadays, resulting from the cholinergic deficit emerging in the brains of AD patients. Shortage of the neurotransmitters, acetylcholine and butyrylcholine has been demonstrated, and therefore, inhibition of the enzymes; acetylcholinesterase (AChE) and butyrylcholinesterase (BChE) that break down acetylcholine and butyrylcholine has become a standard approach for AD treatment. However, cholinesterase inhibitors are only effective in symptomatic treatment and have no ability to impede the disease. The pathogenesis of AD is highly complex and another hypothesis is the formation of amyloid plaques containing beta-amyloid peptide, which causes neurolesions in the brains of AD patients. Beta-amyloid peptide is generated after the sequential cleavage of amyloid precursor protein, especially by the beta- and gamma-secretase in the amyloidogenic pathway. The secretases involved in the processing of amyloid precursor protein are of particular interest and, consequently, the inhibition of secretase enzyme family of protease type has become another desired treatment strategy for AD. On the other hand, medicinal plants are attractive sources for drug research and development as they produce chemically-varying molecules with preferred biological activities. The aim of this article is to review the available data on selected inhibitors from plant secondary metabolites with emphasis on cholinesterase, prolyl endopeptidase, and secretase enzyme families as being the current treatments of AD.

Synthesis and cholinesterase inhibition of cativic acid derivatives.

PubMed

Alza, Natalia P; Richmond, Victoria; Baier, Carlos J; Freire, Eleonora; Baggio, Ricardo; Murray, Ana Paula

2014-08-01

Alzheimer's disease (AD) is a neurodegenerative disorder associated with memory impairment and cognitive deficit. Most of the drugs currently available for the treatment of AD are acetylcholinesterase (AChE) inhibitors. In a preliminary study, significant AChE inhibition was observed for the ethanolic extract of Grindelia ventanensis (IC₅₀=0.79 mg/mL). This result prompted us to isolate the active constituent, a normal labdane diterpenoid identified as 17-hydroxycativic acid (1), through a bioassay guided fractionation. Taking into account that 1 showed moderate inhibition of AChE (IC₅₀=21.1 μM), selectivity over butyrylcholinesterase (BChE) (IC₅₀=171.1 μM) and that it was easily obtained from the plant extract in a very good yield (0.15% w/w), we decided to prepare semisynthetic derivatives of this natural diterpenoid through simple structural modifications. A set of twenty new cativic acid derivatives (3-6) was prepared from 1 through transformations on the carboxylic group at C-15, introducing a C2-C6 linker and a tertiary amine group. They were tested for their inhibitory activity against AChE and BChE and some structure-activity relationships were outlined. The most active derivative was compound 3c, with an IC₅₀ value of 3.2 μM for AChE. Enzyme kinetic studies and docking modeling revealed that this inhibitor targeted both the catalytic active site and the peripheral anionic site of this enzyme. Furthermore, 3c showed significant inhibition of AChE activity in SH-SY5Y human neuroblastoma cells, and was non-cytotoxic. Copyright © 2014 Elsevier Ltd. All rights reserved.

Exposure to triaryl phosphates: metabolism and biomarkers of exposure

PubMed Central

Furlong, Clement E.

2013-01-01

The leakage of tricresyl phosphate-containing engine lubricants into aircraft cabin air, either from worn or defective engine seals or under normal operating conditions, is a serious concern for both the health and safety of the cabin occupants, since the oil contains one to five percent tricresyl phosphate (TCP) esters, known neurotoxins. The exposure of pilots is a particular concern since their impairment can affect their safe operation of the aircraft. Mass spectrometric (MS)-based protocols for documenting exposures of individuals are described that entail a rapid purification of the TCP-modified plasma enzyme butyrylcholinesterase (BChE). Following protease digestion of BChE, the modified active site peptide is characterized by MS analysis. Approaches for identifying safer engine oil additives are also described. Some general comments regarding the necessity of improving the quality and safety of the cabin air supply are presented. PMID:24285929

The significance of the measurement of serum xanthine oxidase and oxidation markers in patients with acute organophosphorus pesticide poisoning.

PubMed

Zhang, J-W; Lv, G-C; Zhao, Y

2010-01-01

This study investigated whether xanthine oxidase (XO) plays an important role in the mechanism of toxicity of acute organophosphorus pesticide poisoning (AOPP). The serum activities of XO, superoxide dismutase (SOD), paraoxonase-1 (PON1), butyrylcholinesterase (BChE) and malondialdehyde (MDA) were compared in 49 patients with AOPP and 50 age- and gender-matched healthy controls. Serum XO and MDA activities were higher and the serum SOD, PON1 and BChE activities were lower in the AOPP patients compared with the controls. Pearson correlation analysis demonstrated a significant negative correlation between XO activity and the SOD, PON1 and BChE activities, but a significant positive correlation between XO activity and MDA. These results suggest that increased activity of XO and decreased antioxidant enzyme activity contribute to the development of oxidative injury in AOPP patients. Thus, effective antioxidant therapy may be a therapeutic option following AOPP.

Biological Evaluation of Azomethine-dihydroquinazolinone Conjugates as Cancer and Cholinesterase Inhibitors.

PubMed

Iqbal, Jamshed; Saeed, Aamer; Shah, Syed J A; al-Rashida, Mariya; Shams-ul Mahmood

2016-01-01

In an attempt to discover novel anti-cancer agents and potent cholinesterase inhibitors, 11 azomethine-dihydroquinazolinone conjugates were evaluated against lung carcinoma cells and cholinesterases. Most of the compounds exhibited significant cytotoxicity at low micromolar concentrations and were less toxic to normal cells. After 24 h incubation period, 2i showed maximum cytotoxicity. The 4-bromine substituted compounds showed higher acetylcholinesterase (AChE) inhibitory activity than other screened compounds. The most active compound 2c, among the series, had an IC50 value 209.8 µM against AChE. The tested compounds showed less inhibition against butyrylcholinesterase. Molecular docking studies were performed in order to investigate the plausible binding modes of synthesized compounds. The compounds can be further optimized to treat cancer and Alzheimer's disease. These derivatives may open new pathways for introducing new therapies for curing cancer and senile dementia.

Ionic liquid mediated synthesis and molecular docking study of novel aromatic embedded Schiff bases as potent cholinesterase inhibitors.

PubMed

Abd Razik, Basma M; Osman, Hasnah; Basiri, Alireza; Salhin, Abdussalam; Kia, Yalda; Ezzat, Mohammed Oday; Murugaiyah, Vikneswaran

2014-12-01

Novel aromatic embedded Schiff bases have been synthesized in ionic liquid [bmim]Br and evaluated in vitro for their acetylcholinesterase (AChE) and butyrylcholinesterase (BChE) enzymes inhibitory activities. Among the newly synthesized compounds, 5f, 5h and 7j displayed higher AChE enzyme inhibitory activities than standard drug, galanthamine, with IC50 values of 1.88, 2.05 and 2.03μM, respectively. Interestingly, all the compounds except for compound 5c displayed higher BChE inhibitories than standard with IC50 values ranging from 3.49 to 19.86μM. Molecular docking analysis for 5f and 7j possessing the most potent AChE and BChE inhibitory activities, disclosed their binding interaction templates to the active site of AChE and BChE enzymes, respectively. Copyright © 2014 Elsevier Inc. All rights reserved.

Design, synthesis and evaluation of novel tacrine-coumarin hybrids as multifunctional cholinesterase inhibitors against Alzheimer's disease.

PubMed

Xie, Sai-Sai; Wang, Xiao-Bing; Li, Jiang-Yan; Yang, Lei; Kong, Ling-Yi

2013-06-01

A series of tacrine-coumarin hybrids (8a-t) were designed, synthesized and evaluated as multifunctional cholinesterase (ChE) inhibitors against Alzheimer's disease (AD). The screening results showed that most of them exhibited a significant ability to inhibit ChE and self-induced β-amyloid (Aβ) aggregation, and to act as metal chelators. Especially, 8f displayed the greatest ability to inhibit acetylcholinesterase (AChE, IC50 = 0.092 μM) and Aβ aggregation (67.8%, 20 μM). It was also a good butyrylcholinesterase inhibitor (BuChE, IC50 = 0.234 μM) and metal chelator. Besides, kinetic and molecular modeling studies indicated that 8f was a mixed-type inhibitor, binding simultaneously to active, peripheral and mid-gorge sites of AChE. These results suggested that 8f might be an excellent multifunctional agent for AD treatment. Copyright © 2013 Elsevier Masson SAS. All rights reserved.

Synthesis, characterization, and molecular docking analysis of novel benzimidazole derivatives as cholinesterase inhibitors.

PubMed

Yoon, Yeong Keng; Ali, Mohamed Ashraf; Wei, Ang Chee; Choon, Tan Soo; Khaw, Kooi-Yeong; Murugaiyah, Vikneswaran; Osman, Hasnah; Masand, Vijay H

2013-08-01

Two series of novel acetylcholinesterase (AChE) and butyrylcholinesterase (BChE) inhibitors containing benzimidazole core structure were synthesized by a four-step reaction pathway starting from 4-fluoro-3-nitrobenzoic acid as the basic compound. The structure of the novel benzimidazoles was characterized and confirmed by the elemental and mass spectral analyses as well as (1)H NMR spectroscopic data. Of the 34 novel synthesized compounds, three benzimidazoles revealed AChE inhibition with IC50<10 μM. The highest inhibitory activity (IC50=5.12 μM for AChE and IC50=8.63 μM for BChE) corresponds to the compound 5IIc (ethyl 1-(3-(1H-imidazol-1-yl)propyl)-2-(4-nitrophenyl)-1H-benzo[d]imidazole-5-carboxylate). The relationship between lipophilicity and the chemical structures as well as their limited structure-activity relationship was discussed. Copyright © 2013 Elsevier Inc. All rights reserved.

Design, synthesis and evaluation of 4-dimethylamine flavonoid derivatives as potential multifunctional anti-Alzheimer agents.

PubMed

Luo, Wen; Wang, Ting; Hong, Chen; Yang, Ya-Chen; Chen, Ying; Cen, Juan; Xie, Song-Qiang; Wang, Chao-Jie

2016-10-21

A new series of 4-dimethylamine flavonoid derivatives were designed and synthesized as potential multifunctional anti-Alzheimer agents. The inhibition of cholinesterase activity, self-induced β-amyloid (Aβ) aggregation, and antioxidant activity by these derivatives was investigated. Most of the compounds exhibited potent acetylcholinesterase (AChE) and butyrylcholinesterase (BChE) inhibitory activity. A Lineweaver-Burk plot and molecular modeling study showed that these compounds targeted both the catalytic active site (CAS) and peripheral anionic site (PAS) of AChE. The derivatives showed potent self-induced Aβ aggregation inhibition and peroxyl radical absorbance activity. Moreover, compound 6d significantly protected PC12 neurons against H2O2-induced cell death at low concentrations. Thus, these compounds could become multifunctional agents for further development for the treatment of AD. Copyright © 2016 Elsevier Masson SAS. All rights reserved.

QSAR for cholinesterase inhibition by organophosphorus esters and CNDO/2 calculations for organophosphorus ester hydrolysis

NASA Technical Reports Server (NTRS)

Johnson, H.; Kenley, R. A.; Rynard, C.; Golub, M. A.

1985-01-01

Quantitative structure-activity relationships were derived for acetyl- and butyrylcholinesterase inhibition by various organophosphorus esters. Bimolecular inhibition rate constants correlate well with hydrophobic substituent constants, and with the presence or absence of catonic groups on the inhibitor, but not with steric substituent constants. CNDO/2 calculations were performed on a separate set of organophosphorus esters, RR'P(O)X, where R and R' are alkyl and/or alkoxy groups and X is fluorine, chlorine or a phenoxy group. For each subset with the same X, the CNDO-derived net atomic charge at the central phosphorus atom in the ester correlates well with the alkaline hydrolysis rate constant. For the whole set of esters with different X, two equations were derived that relate either charge and leaving group steric bulk, or orbital energy and bond order to the hydrogen hydrolysis rate constant.

QSAR for cholinesterase inhibition by organophosphorus esters and CNDO/2 calculations for organophosphorus ester hydrolysis. [quantitative structure-activity relationship, complete neglect of differential overlap

NASA Technical Reports Server (NTRS)

Johnson, H.; Kenley, R. A.; Rynard, C.; Golub, M. A.

1985-01-01

Quantitative structure-activity relationships were derived for acetyl- and butyrylcholinesterase inhibition by various organophosphorus esters. Bimolecular inhibition rate constants correlate well with hydrophobic substituent constants, and with the presence or absence of cationic groups on the inhibitor, but not with steric substituent constants. CNDO/2 calculations were performed on a separate set of organophosphorus esters, RR-primeP(O)X, where R and R-prime are alkyl and/or alkoxy groups and X is fluorine, chlorine or a phenoxy group. For each subset with the same X, the CNDO-derived net atomic charge at the central phosphorus atom in the ester correlates well with the alkaline hydrolysis rate constant. For the whole set of esters with different X, two equations were derived that relate either charge and leaving group steric bulk, or orbital energy and bond order to the hydrolysis rate constant.

Tolerance of adult mallards to subacute ingestion of crude petroleum oil

USGS Publications Warehouse

Rattner, B.A.

1981-01-01

Adult male mallards were fed untreated mash or mash containing 1.5% Prudhoe Bay crude oil for 7 days ad lib. During the initial 24 h of exposure to crude petroleum oil, ducks consumed less mash (P less than 0.05) and lost approx. 3.5% of their initial body weight (P less than 0.05), however, neither intake nor body weight differ between groups on days 2-7. Plasma samples collected between 09.00 and 10.00 h on days 0, 1, 3, or 7 indicated that corticosterone, glucose, thyroxine, total protein, and uric acid concentrations, and the activities of aspartate aminotransferase (AST), alanine aminotransferase (ALT), and butyrylcholinesterase (BCHE) were not affected by treatment. These findings suggest that adult mallards may be able to tolerate large quantities of crude petroleum oil mixed in their diet (approx. 25 ml over a 7-day period) without overt or biochemical indications of distress.

Relationship Between Paraoxonase-1 and Butyrylcholinesterase Activities and Nutritional Status in Mexican Children.

PubMed

Ramírez-Jiménez, Rocío; Martínez-Salazar, María Fernanda; Almenares-López, Damianys; Yáñez-Estrada, Leticia; Monroy-Noyola, Antonio

2018-03-01

The enzymes butyrylcholinesterase (BuChE) and paraoxonase-1 (PON1) are the primary bioscavenging enzymes in serum and exhibit antioxidant and anti-inflammatory activities. PON1 has been associated with diseases caused by high oxidative stress, whereas BuChE appears to be involved in the pathophysiology of the metabolic syndrome and related disorders. It has been suggested that children from rural communities in Mexico may have a predisposition to develop obesity or type 2 diabetes during adolescence or adulthood. The objective of this study was to determine whether associations exist between the paraoxonase (PONase)/arylesterase (AREase) activity of PON1, its PON1-Q192R and PON1-L55M polymorphisms, and BuChE activity with the nutritional status and lipid profiles in a group of children from rural communities in Mexico. A group of 97 boys and girls from a rural community in Mexico were assessed for body mass index, the enzymatic activities of BuChE, PONase, and AREase were measured in serum, and their lipid profiles were determined. Genetic polymorphisms of PON1-L55M and PON1-Q192R were determined by polymerase chain reaction-restriction fragment length polymorphism (PCR-RFLP). The children were classified into four groups: thinness, normal weight, overweight, and obese. Of the children studied, 34.4% were overweight and obese. The mean age of the participants was 9.5 years (standard deviation = 1.8). The L allele of the PON1-L55M genotype was the most frequent (83.3%), and the R allele of the PON1-Q192R genotype was the most frequent (61.8%). Overweight and obese children had higher values of BuChE, total cholesterol, triglycerides (TG), and lower high-density lipoprotein (HDL-C) values than children with thinness or normal weight (P = 0.028, P = 0.019, P = 0.004, P = 0.069 and P = 0.021, respectively). The levels of AREase and PONase and the prevalence of PON1-L55M and PON1-Q192R genotypes were similar between groups (P = 0.484 and P = 0.380, respectively). This study establishes a positive association of BuChE activity with nutritional status and serum TG.

Differential effects of developmental hypo- and hyperthyroidism on acetylcholinesterase and butyrylcholinesterase activity in the spinal cord of developing postnatal rat pups.

PubMed

Koohestani, Faezeh; Brown, Chester M; Meisami, Esmail

2012-11-01

The plasticity and vulnerability of the rat spinal cord (SC) during postnatal development has been less investigated compared to other CNS structures. In this study, we determined the effects of thyroid hormonal (TH) deficiency and excess on postnatal growth and neurochemical development of the rat SC. The growth as well as the specific and total activity of acetylcholinesterase (AChE) and butyrylcholinesterase (BuChE) enzymes of the SC were determined in hypo- and hyperthyroid rat pups at postnatal (P) days P1, P5, P10 and P21 (weaning), and were compared to age-matched untreated normal controls. AChE is a cholinergic synaptic enzyme while BuChE is a metabolic enzyme mainly found in glial cells and neurovascular cells. The SC is rich in somatic motor, autonomic cholinergic neurons and associated interneurons. Daily subcutaneous injection of pups with thyroxine (T4) and administration of antithyroid goitrogen propylthiouracil (PTU) in the litter's drinking water were used to induce hyper- and hypothyroidism, respectively. Enzyme assays were carried out spectrophotometrically at the above-mentioned ages, using SC homogenates with acetylthiocholine-chloride as the substrate, together with specific cholinesterase inhibitors, which specifically target AChE and BuChE. SC weights were significantly lower at P10 and P21 in hypothyroid pups but unchanged in the hyperthyroid ones. Hypothyroidism significantly reduced both specific and total AChE activity in SC of P10 and P21 rat pups, while having no effects on the BuChE activity, although total BuChE activity was decreased due to reduced total tissue weight. In contrast both specific and total AChE activities were markedly and significantly increased (>100%) in the P10 and P21 hyperthyroid pups. However, BuChE specific activity was unaffected by this treatment. The results indicate that hypothyroid condition significantly reduces, while hyperthyroidism increases, the postnatal development of cholinergic synapses, thereby influencing the functional development of this major sensory and motor structure. However, the neurochemical development of glia and other non-neuronal cells, where BuChE is mainly localized, is comparatively unaffected in these abnormal developmental conditions. Copyright © 2012 ISDN. Published by Elsevier Ltd. All rights reserved.

Pharmacodynamic, pharmacokinetic and pharmacogenetic aspects of drugs used in the treatment of Alzheimer's disease.

PubMed

Noetzli, Muriel; Eap, Chin B

2013-04-01

With the aging population and its rapidly increasing prevalence, dementia has become an important public health concern in developed and developing countries. To date, the pharmacological treatment is symptomatic and based on the observed neurotransmitter disturbances. The four most commonly used drugs are donepezil, galantamine, rivastigmine and memantine. Donepezil, galantamine and rivastigmine are acetylcholinesterase inhibitors with different pharmacodynamic and pharmacokinetic profiles. Donepezil inhibits selectively the acetylcholinesterase and has a long elimination half-life (t(1/2)) of 70 h. Galantamine is also a selective acetylcholinesterase inhibitor, but also modulates presynaptic nicotinic receptors. It has a t(1/2) of 6-8 h. Donepezil and galantamine are mainly metabolised by cytochrome P450 (CYP) 2D6 and CYP3A4 in the liver. Rivastigmine is a so-called 'pseudo-irreversible' inhibitor of acetylcholinesterase and butyrylcholinesterase. The t(1/2) of the drug is very short (1-2 h), but the duration of action is longer as the enzymes are blocked for around 8.5 and 3.5 h, respectively. Rivastigmine is metabolised by esterases in liver and intestine. Memantine is a non-competitive low-affinity antagonist of the NMDA receptor with a t(1/2) of 70 h. Its major route of elimination is unchanged via the kidneys. Addressing the issue of inter-patient variability in treatment response might be of special importance for the vulnerable population taking anti-dementia drugs. Pharmacogenetic considerations might help to avoid multiple medication changes due to non-response and/or adverse events. Some pharmacogenetic studies conducted on donepezil and galantamine reported an influence of the CYP2D6 genotype on the pharmacokinetics of the drugs and/or on the response to treatment. Moreover, polymorphisms in genes of the cholinergic markers acetylcholinesterase, butyrylcholinesterase, choline acetyltransferase and paraoxonase were found to be associated with better clinical response to acetylcholinesterase inhibitors. However, confirmation studies in larger populations are necessary to establish evidence of which subgroups of patients will most likely benefit from anti-dementia drugs. The aim of this review is to summarize the pharmacodynamics and pharmacokinetics of the four commonly used anti-dementia drugs and to give an overview on the current knowledge of pharmacogenetics in this field.

Reaction pathways and free energy profiles for cholinesterase-catalyzed hydrolysis of 6-monoacetylmorphine

PubMed Central

Qiao, Yan; Han, Keli; Zhan, Chang-Guo

2014-01-01

As the most active metabolite of heroin, 6-monoacetylmorphine (6-MAM) can penetrate into the brain for the rapid onset of heroin effects. The primary enzymes responsible for the metabolism of 6-MAM to the less potent morphine in humans are acetylcholinesterase (AChE) and butyrylcholinesterase (BChE). The detailed reaction pathways for AChE- and BChE-catalyzed hydrolysis of 6-MAM to morphine have been explored, for the first time, in the present study by performing first-principles quantum mechanical/molecular mechanical free energy calculations. It has been demonstrated that the two enzymatic reaction processes follow the similar catalytic reaction mechanism, and the whole catalytic reaction pathway for each enzyme consists of four reaction steps. According to the calculated results, the second reaction step associated with the transition state TS2a/TS2b should be rate-determining for the AChE/BChE-catalyzed hydrolysis, and the free energy barrier calculated for the AChE-catalyzed hydrolysis (18.3 kcal/mol) is 2.5 kcal/mol lower than that for the BChE-catalyzed hydrolysis (20.8 kcal/mol). The free energy barriers calculated for the AChE- and BChE-catalyzed reactions are in good agreement with the experimentally derived activation free energies (17.5 and 20.7 kcal/mol for the AChE- and BChE-catalyzed reactions, respectively). Further structural analysis reveals that the aromatic residues Phe295 and Phe297 in the acyl pocket of AChE (corresponding to Leu286 and Val288 in BChE) contribute to the lower energy of TS2a relative to TS2b. The obtained structural and mechanistic insights could be valuable for use in future rational design of a novel therapeutic treatment of heroin abuse. PMID:24595354

The proof-of-concept of ASS234: Peripherally administered ASS234 enters the central nervous system and reduces pathology in a male mouse model of Alzheimer disease.

PubMed

Serrano, Mari Paz; Herrero-Labrador, Raquel; Futch, Hunter S; Serrano, Julia; Romero, Alejandro; Fernandez, Ana Patricia; Samadi, Abdelouahid; Unzeta, Mercedes; Marco-Contelles, Jose; Martínez-Murillo, Ricardo

2017-01-01

The heterogeneity of Alzheimer disease requires the development of multitarget drugs for treating the symptoms of the disease and its progression. Both cholinergic and monoamine oxidase dysfunctions are involved in the pathological process. Thus, we hypothesized that the development of therapies focused on these targets might be effective. We have developed and assessed a new product, coded ASS234, a multipotent acetyl and butyrylcholinesterase/monoamine oxidase A-B inhibitor with a potent inhibitory effect on amyloid-β aggregation as well as antioxidant and antiapoptotic properties. But there is a need to reliably correlate in vitro and in vivo drug release data. We examined the effect of ASS234 on cognition in healthy adult C57BL/6J mice in a model of scopolamine-induced cognitive impairment that often accompanies normal and pathological aging. Also, in a characterized transgenic APPswe/PS1ΔE9 mouse model of Alzheimer disease, we examined the effects of short-term ASS234 treatment on plaque deposition and gliosis using immunohistochemistry. Toxicology of ASS234 was assessed using a quantitative high-throughput in vitro cytotoxicity screening assay following the MTT assay method in HepG2 liver cells. In vivo, ASS234 significantly decreased scopolamine-induced learning deficits in C57BL/6J mice. Also, reduction of amyloid plaque burden and gliosis in the cortex and hippocampus was assessed. In vitro, ASS234 exhibited lesser toxicity than donepezil and tacrine. The study was conducted in male mice only. Although the Alzheimer disease model does not recapitulate all features of the human disease, it exhibits progressive monoaminergic neurodegeneration. ASS234 is a promising alternative drug of choice to treat the cognitive decline and neurodegeneration underlying Alzheimer disease.

Cocaine cardiovascular effects and pharmacokinetics after treatment with the acetylcholinesterase inhibitor donepezil.

PubMed

Grasing, Kenneth; Mathur, Deepan; DeSouza, Cherilyn; Newton, Thomas F; Moody, David E; Sturgill, Marc

2016-08-01

In rodents, cholinesterase inhibitors can cause sustained decreases in the reinforcing effects of cocaine. Nonetheless, cocaine is metabolized by butyrylcholinesterase (BuChE), raising concerns that cholinesterase inhibition could increase its peripheral concentrations, perhaps augmenting toxicity. Although donepezil is approved for use in patients and selective for inhibiting acetylcholinesterase over BuChE, no studies have reported cocaine bioavailability in human subjects receiving donepezil. Twelve cocaine-dependent veterans received three days of treatment with either oral placebo or 5 mg daily of donepezil, followed by cross-over to the opposite treatment. During both oral treatments, double-blind intravenous cocaine was administered at .0, .18, and .36 mg/kg in a laboratory setting, followed by determinations of heart rate, blood pressure, and plasma concentrations of cocaine and major metabolites. Intravenous cocaine produced dose-related increases in systolic blood pressure that were most pronounced over the initial 30 minutes after treatment. Oral donepezil attenuated drug-induced elevations of systolic blood pressure following low-dose cocaine (.18 mg/kg). No significant difference in blood pressure following treatment with placebo or donepezil after high-dose cocaine (.36 mg/kg). Peak values of blood pressure and heart rate were unaffected by donepezil. Plasma concentrations of cocaine and metabolites did not differ in donepezil- and placebo-treated participants. We conclude that donepezil can attenuate drug-induced increases in systolic blood pressure following low-dose cocaine, but does not otherwise modify the cardiovascular effects of intravenous cocaine. Clinically significant changes in cocaine bioavailability and cardiovascular effects do not occur following this dose of donepezil. (Am J Addict 2016;25:392-399). © 2016 American Academy of Addiction Psychiatry.

A Comprehensive Evaluation of the Efficacy of Leading Oxime Therapies in Guinea Pigs Exposed to Organophosphorus Chemical Warfare Agents or Pesticides

PubMed Central

Wilhelm, Christina M.; Snider, Thomas H.; Babin, Michael C.; Jett, David A.; Platoff, Gennady E.; Yeung, David T.

2014-01-01

The currently fielded pre-hospital therapeutic regimen for the treatment of organophosphorus (OP) poisoning in the United States (U.S.) is the administration of atropine in combination with an oxime antidote (2-PAM Cl) to reactivate inhibited acetylcholinesterase (AChE). Depending on clinical symptoms, an anticonvulsant, e.g., diazepam, may also be administered. Unfortunately, 2-PAM Cl does not offer sufficient protection across the range of OP threat agents, and there is some question as to whether it is the most effective oxime compound available. The objective of the present study is to identify an oxime antidote, under standardized and comparable conditions, that offers protection at the FDA approved human equivalent dose (HED) of 2-PAM Cl against tabun (GA), sarin (GB), soman (GD), cyclosarin (GF), and VX, and the pesticides paraoxon, chlorpyrifos oxon, and phorate oxon. Male Hartley guinea pigs were subcutaneously challenged with a lethal level of OP and treated at approximately 1 min post challenge with atropine followed by equimolar oxime therapy (2-PAM Cl, HI-6 DMS, obidoxime Cl2, TMB-4, MMB4-DMS, HLö-7 DMS, MINA, and RS194B) or therapeutic-index (TI) level therapy (HI-6 DMS, MMB4-DMS, MINA, and RS194B). Clinical signs of toxicity were observed for 24 hours post challenge and blood cholinesterase [AChE and butyrylcholinesterase (BChE)] activity was analyzed utilizing a modified Ellman’s method. When the oxime is standardized against the HED of 2-PAM Cl for guinea pigs, the evidence from clinical observations, lethality, quality of life (QOL) scores, and cholinesterase reactivation rates across all OPs indicated that MMB4 DMS and HLö-7 DMS were the two most consistently efficacious oximes. PMID:25448441

Willughbeia cochinchinensis prevents scopolamine-induced deficits in memory, spatial learning, and object recognition in rodents.

PubMed

Can, Mao Van; Tran, Anh Hai; Pham, Dam Minh; Dinh, Bao Quoc; Le, Quan Van; Nguyen, Ba Van; Nguyen, Mai Thanh Thi; Nguyen, Hai Xuan; Nguyen, Nhan Trung; Nishijo, Hisao

2018-03-25

Willughbeia cochinchinensis (WC) has been used in Vietnamese traditional medicine for the treatment of dementia as well as diarrhea, heartburn, and cutaneous abscess and as a diuretic. Alzheimer's disease (AD) is one of the most prevalent diseases in elderly individuals. Acetylcholinesterase (AChE) and butyrylcholinesterase (BChE) inhibitors have been widely used to treat patients with AD. In the present study, we investigated anti-AChE and anti-BChE activities of a natural product, WC, for its potential applications in therapies to prevent/treat dementia. First, compounds extracted from WC were tested for their AChE and BChE inhibitory activities in vitro. Second, in vivo behavioral experiments were performed to investigate the effects of WC at doses of 100, 150, and 200mg/kg on scopolamine (1.5mg/kg)-induced memory and cognitive deficits in mice. The behavior of mice treated with and without WC and/or scopolamine was tested using the Y-maze, Morris water maze, and novel object recognition task. The results of the in vitro assay demonstrated anti-AChE and anti-BChE activities of the compounds extracted from WC. The results of behavioral experiments showed that the administration of WC prevented 1) scopolamine-induced decrease in spontaneous alternation (%) behavior in the Y-maze, 2) scopolamine-induced deficits in spatial learning and memory in the Morris water maze, and 3) scopolamine-induced deficits in novel object recognition. These results indicate that WC prevents cognitive and memory deficits induced by scopolamine injection. Our findings suggest that WC may represent a novel candidate for the treatment of memory and cognitive deficits in humans with dementia. Copyright © 2017. Published by Elsevier B.V.

Identifying Safer Anti-Wear Triaryl Phosphate Additives for Jet Engine Lubricants

PubMed Central

Baker, Paul E.; Cole, Toby B.; Cartwright, Megan; Suzuki, Stephanie M.; Thummel, Kenneth E.; Lin, Yvonne S.; Co, Aila L.; Rettie, Allan E.; Kim, Jerry H.; Furlong, Clement E.

2013-01-01

Individuals aboard jet aircraft may be exposed to potentially toxic triaryl organophosphate anti-wear lubricant additives (TAPs) that are converted by cytochromes P450 into toxic metabolites. Consequences of exposure could be reduced by using less toxic TAPs. Our goal was to determine whether an in vitro assay for inhibition of butyrylcholinesterase (BChE) by bioactivated TAPs would be predictive of inhibition of serine active-site enzymes in vivo. The in vitro assay involved TAP bioactivation with liver microsomes and NADPH, followed by incubation with human BChE and measurement of BChE activity. Of 19 TAPs tested, tert-butylated isomers produced the least BChE inhibition. To determine the relevance of these results in vivo, mice were exposed to Durad 125 (D125; a commercial mixture of TAP esters) or to TAPs demonstrating low or no BChE inhibition when assayed in vitro. Inhibition of BChE by bioactivated TAPs in vitro correlated well with inhibition of other serine active-site enzymes in vivo, with the exception of brain acetylcholinesterase and neuropathy target esterase (NTE), which were not inhibited by any TAP tested following single exposures. A recombinant catalytic domain of NTE (rNEST) exhibited classical kinetic properties of NTE. The metabolite of tri-(o-cresyl) phosphate (ToCP), 2-(o-cresyl)-4H-1,3,2-benzodioxaphosphoran-2-one (CBDP), inhibited rNEST in vitro, but with an IC50 value almost 6-times higher than for inhibition of BChE. Physiologically-relevant concentrations of the flavonoid, naringenin, dramatically reduced D125 bioconversion in vitro. The in vitro assay should provide a valuable tool for prescreening candidate TAP anti-wear additives, identifying safer additives and reducing the number of animals required for in vivo toxicity testing. PMID:23085349

Acetamide Derivatives of Chromen-2-ones as Potent Cholinesterase Inhibitors.

PubMed

Prasad, Suchita; Kumar, Bipul; Kumar, Shiv; Chand, Karam; Kamble, Shashank S; Gautam, Hemant K; Sharma, Sunil K

2017-08-01

Alzheimer's disease (AD), a neurodegenerative disorder, is a serious medical issue worldwide with drastic social consequences. Inhibition of cholinesterase is one of the rational and effective approaches to retard the symptoms of AD and, hence, consistent efforts are being made to develop efficient anti-cholinesterase agents. In pursuit of this, a series of 19 acetamide derivatives of chromen-2-ones were synthesized and evaluated for their acetylcholinesterase (AChE) and butyrylcholinesterase (BChE) inhibitory potential. All the synthesized compounds exhibited significant anti-AChE and anti-BChE activity, with IC 50 values in the range of 0.24-10.19 μM and 0.64-30.08 μM, respectively, using donepezil hydrochloride as the standard. Out of 19 compounds screened, 3 compounds, viz. 22, 40, and 43, caused 50% inhibition of AChE at 0.24, 0.25, and 0.25 μM, respectively. A kinetic study revealed them to be mixed-type inhibitors, binding with both the CAS and PAS sites of AChE. The above-selected compounds were found to be effective inhibitors of AChE-induced and self-mediated Aβ 1-42 aggregation. ADMET predictions demonstrated that these compounds may possess suitable blood-brain barrier (BBB) permeability. Hemolytic assay results revealed that these compounds did not lyse human RBCs up to a thousand times of their IC 50 value. MTT assays performed for the shortlisted compounds showed them to be negligibly toxic after 24 h of treatment with the SH-SY5Y neuroblastoma cells. These results provide insights for further optimization of the scaffolds for designing the next generation of compounds as lead cholinesterase inhibitors. © 2017 Deutsche Pharmazeutische Gesellschaft.

Cocaine Cardiovascular Effects and Pharmacokinetics after Treatment with the Acetylcholinesterase Inhibitor Donepezil

PubMed Central

Grasing, Kenneth; Mathur, Deepan; DeSouza, Cherilyn; Newton, Thomas F.; Moody, David E.; Sturgill, Marc

2016-01-01

Background In rodents, cholinesterase inhibitors can cause sustained decreases in the reinforcing effects of cocaine. Nonetheless, cocaine is metabolized by butyrylcholinesterase (BuChE), raising concerns that cholinesterase inhibition could increase its peripheral concentrations, perhaps augmenting toxicity. Although donepezil is approved for use in patients and selective for inhibiting acetylcholinesterase over BuChE, no studies have reported cocaine bioavailability in human subjects receiving donepezil. Methods Twelve cocaine-dependent veterans received three days of treatment with either oral placebo or 5 mg daily of donepezil, followed by cross-over to the opposite treatment. During both oral treatments, double-blind intravenous cocaine was administered at 0.0, 0.18, 0.36 mg/kg in a laboratory setting, followed by determinations of heart rate, blood pressure, and plasma concentrations of cocaine and major metabolites. Results Intravenous cocaine produced dose-related increases in systolic blood pressure that were most pronounced over the initial 30 minutes after treatment. Oral donepezil attenuated drug-induced elevations of systolic blood pressure following low-dose cocaine (0.18 mg/kg). No significant difference in blood pressure following treatment with placebo or donepezil after high-dose cocaine (0.36 mg/kg). Peak values of blood pressure and heart rate were unaffected by donepezil. Plasma concentrations of cocaine and metabolites did not differ in donepezil- and placebo- treated participants. Conclusions and Scientific Significance We conclude that donepezil can attenuate drug-induced increases in systolic blood pressure following low-dose cocaine, but does not otherwise modify the cardiovascular effects of intravenous cocaine. Clinically significant changes in cocaine bioavailability and cardiovascular effects do not occur following this dose of donepezil. PMID:27392137

Identifying safer anti-wear triaryl phosphate additives for jet engine lubricants.

PubMed

Baker, Paul E; Cole, Toby B; Cartwright, Megan; Suzuki, Stephanie M; Thummel, Kenneth E; Lin, Yvonne S; Co, Aila L; Rettie, Allan E; Kim, Jerry H; Furlong, Clement E

2013-03-25

Individuals aboard jet aircraft may be exposed to potentially toxic triaryl organophosphate anti-wear lubricant additives (TAPs) that are converted by cytochromes P450 into toxic metabolites. Consequences of exposure could be reduced by using less toxic TAPs. Our goal was to determine whether an in vitro assay for inhibition of butyrylcholinesterase (BChE) by bioactivated TAPs would be predictive of inhibition of serine active-site enzymes in vivo. The in vitro assay involved TAP bioactivation with liver microsomes and NADPH, followed by incubation with human BChE and measurement of BChE activity. Of 19 TAPs tested, tert-butylated isomers produced the least BChE inhibition. To determine the relevance of these results in vivo, mice were exposed to Durad 125 (D125; a commercial mixture of TAP esters) or to TAPs demonstrating low or no BChE inhibition when assayed in vitro. Inhibition of BChE by bioactivated TAPs in vitro correlated well with inhibition of other serine active-site enzymes in vivo, with the exception of brain acetylcholinesterase and neuropathy target esterase (NTE), which were not inhibited by any TAP tested following single exposures. A recombinant catalytic domain of NTE (rNEST) exhibited classical kinetic properties of NTE. The metabolite of tri-(o-cresyl) phosphate (ToCP), 2-(o-cresyl)-4H-1,3,2-benzodioxaphosphoran-2-one (CBDP), inhibited rNEST in vitro, but with an IC(50) value almost 6-times higher than for inhibition of BChE. Physiologically-relevant concentrations of the flavonoid naringenin dramatically reduced D125 bioconversion in vitro. The in vitro assay should provide a valuable tool for prescreening candidate TAP anti-wear additives, identifying safer additives and reducing the number of animals required for in vivo toxicity testing. Copyright © 2012 Elsevier Ireland Ltd. All rights reserved.

Planarian cholinesterase: in vitro characterization of an evolutionarily ancient enzyme to study organophosphorus pesticide toxicity and reactivation.

PubMed

Hagstrom, Danielle; Hirokawa, Hideto; Zhang, Limin; Radic, Zoran; Taylor, Palmer; Collins, Eva-Maria S

2017-08-01

The freshwater planarian Dugesia japonica has recently emerged as an animal model for developmental neurotoxicology and found to be sensitive to organophosphorus (OP) pesticides. While previous activity staining of D. japonica, which possess a discrete cholinergic nervous system, has shown acylthiocholine catalysis, it is unknown whether this is accomplished through an acetylcholinesterase (AChE), butyrylcholinesterase (BChE), or a hybrid esterase and how OP exposure affects esterase activity. Here, we show that the majority of D. japonica cholinesterase (DjChE) activity departs from conventional AChE and BChE classifications. Inhibition by classic protonable amine and quaternary reversible inhibitors (ethopropazine, donepezil, tacrine, edrophonium, BW284c51, propidium) shows that DjChE is far less sensitive to these inhibitors than human AChE, suggesting discrete differences in active center and peripheral site recognition and structures. Additionally, we find that different OPs (chlorpyrifos oxon, paraoxon, dichlorvos, diazinon oxon, malaoxon) and carbamylating agents (carbaryl, neostigmine, physostigmine, pyridostigmine) differentially inhibit DjChE activity in vitro. DjChE was most sensitive to diazinon oxon and neostigmine and least sensitive to malaoxon and carbaryl. Diazinon oxon-inhibited DjChE could be reactivated by the quaternary oxime, pralidoxime (2-PAM), and the zwitterionic oxime, RS194B, with RS194B being significantly more potent. Sodium fluoride (NaF) reactivates OP-DjChE faster than 2-PAM. As one of the most ancient true cholinesterases, DjChE provides insight into the evolution of a hybrid enzyme before the separation into distinct AChE and BChE enzymes found in higher vertebrates. The sensitivity of DjChE to OPs and capacity for reactivation validate the use of planarians for OP toxicology studies.

Cholinesterase activity during embryonic development in the blood-feeding bug Triatoma patagonica.

PubMed

Visciarelli, E C; Chopa, C Sánchez; Picollo, M I; Ferrero, A A

2011-09-01

Triatoma patagonica Del Ponte (Hemiptera: Reduviidae), a vector of Chagas' disease, is widely distributed in Argentina and is found in sylvatic and peridomiciliary ecotopes, as well as occasionally in human dwellings after the chemical control of Triatoma infestans. Anti-cholinesteratic products can be applied in peridomiciliary areas and thus knowledge of cholinesterase activity during embryonic development in this species might contribute further information relevant to effective chemical control. Cholinesterase activity was characterized by reactions to eserine 10(-5) m, to increasing concentrations of substrate and to varying centrifugal speeds. Acetylcholinesterase activity was detected on day 4 and was significant from day 5. A reduction in cholinesterase activity towards acetylthiocholine (ATC) was observed on days 9 and 10 of development. Cholinesterase activity towards ATC and butyrylthiocholine (BTC) in homogenates of eggs was inhibited by eserine 10(-5) m. The shape of the curve indicating levels of inhibition at different concentrations of ATC was typical of acetylcholinesterase. Activity towards BTC did not appear to be inhibited by excess substrate, which parallels the behaviour of butyrylcholinesterases. Cholinesterase activity towards ATC was reduced in supernatant centrifuged at 15 000 g compared with supernatant centrifuged at 1100 g. The cholinesterase system that hydrolyzes mainly ATC seems to belong to the nervous system, as indicated by its behaviour towards the substrates assayed, its greater insolubility and the fact that it evolves parallel to the development of the nervous system. Knowledge of biochemical changes associated with the development and maturation of the nervous system during embryonic development would contribute to the better understanding of anti-cholinesteratic compounds with ovicidal action that might be used in control campaigns against vectors of Chagas' disease. © 2011 The Authors. Medical and Veterinary Entomology © 2011 The Royal Entomological Society.

Naturally Occurring Variations in the Human Cholinesterase Genes: Heritability and Association with Cardiovascular and Metabolic Traits

PubMed Central

Valle, Anne M.; Radić, Zoran; Rana, Brinda K.; Mahboubi, Vafa; Wessel, Jennifer; Shih, Pei-an Betty; Rao, Fangwen; O'Connor, Daniel T.

2011-01-01

Cholinergic neurotransmission in the central and autonomic nervous systems regulates immediate variations in and longer-term maintenance of cardiovascular function with acetylcholinesterase (AChE) activity that is critical to temporal responsiveness. Butyrylcholinesterase (BChE), largely confined to the liver and plasma, subserves metabolic functions. AChE and BChE are found in hematopoietic cells and plasma, enabling one to correlate enzyme levels in whole blood with hereditary traits in twins. Using both twin and unrelated subjects, we found certain single nucleotide polymorphisms (SNPs) in the ACHE gene correlated with catalytic properties and general cardiovascular functions. SNP discovery from ACHE resequencing identified 19 SNPs: 7 coding SNPs (cSNPs), of which 4 are nonsynonymous, and 12 SNPs in untranslated regions, of which 3 are in a conserved sequence of an upstream intron. Both AChE and BChE activity traits in blood were heritable: AChE at 48.8 ± 6.1% and BChE at 81.4 ± 2.8%. Allelic and haplotype variations in the ACHE and BCHE genes were associated with changes in blood AChE and BChE activities. AChE activity was associated with BP status and SBP, whereas BChE activity was associated with features of the metabolic syndrome (especially body weight and BMI). Gene products from cDNAs with nonsynonymous cSNPs were expressed and purified. Protein expression of ACHE nonsynonymous variant D134H (SNP6) is impaired: this variant shows compromised stability and altered rates of organophosphate inhibition and oxime-assisted reactivation. A substantial fraction of the D134H instability could be reversed in the D134H/R136Q mutant. Hence, common genetic variations at ACHE and BCHE loci were associated with changes in corresponding enzymatic activities in blood. PMID:21493754

Evaluation of Candidate Genes for Cholinesterase Activity in Farmworkers Exposed to Organophosphorus Pesticides: Association of Single Nucleotide Polymorphisms in BCHE

PubMed Central

Howard, Timothy D.; Hsu, Fang-Chi; Grzywacz, Joseph G.; Chen, Haiying; Quandt, Sara A.; Vallejos, Quirina M.; Whalley, Lara E.; Cui, Wei; Padilla, Stephanie; Arcury, Thomas A.

2010-01-01

Background Organophosphate pesticides act as cholinesterase inhibitors. For those with agricultural exposure to these chemicals, risk of potential exposure-related health effects may be modified by genetic variability in cholinesterase metabolism. Cholinesterase activity is a useful, indirect measurement of pesticide exposure, especially in high-risk individuals such as farmworkers. To understand fully the links between pesticide exposure and potential human disease, analyses must be able to consider genetic variability in pesticide metabolism. Objectives We studied participants in the Community Participatory Approach to Measuring Farmworker Pesticide Exposure (PACE3) study to determine whether cholinesterase levels are associated with single-nucleotide polymorphisms (SNPs) involved in pesticide metabolism. Methods Cholinesterase levels were measured from blood samples taken from 287 PACE3 participants at up to four time points during the 2007 growing season. We performed association tests of cholinesterase levels and 256 SNPs in 30 candidate genes potentially involved in pesticide metabolism. A false discovery rate (FDR) p-value was used to account for multiple testing. Results Thirty-five SNPs were associated (unadjusted p < 0.05) based on at least one of the genetic models tested (general, additive, dominant, and recessive). The strongest evidence of association with cholinesterase levels was observed with two SNPs, rs2668207 and rs2048493, in the butyrylcholinesterase (BCHE) gene (FDR adjusted p = 0.15 for both; unadjusted p = 0.00098 and 0.00068, respectively). In participants with at least one minor allele, cholinesterase levels were lower by 4.3–9.5% at all time points, consistent with an effect that is independent of pesticide exposure. Conclusions Common genetic variation in the BCHE gene may contribute to subtle changes in cholinesterase levels. PMID:20529763

Use of a novel radiometric method to assess the inhibitory effect of donepezil on acetylcholinesterase activity in minimally diluted tissue samples

PubMed Central

Kikuchi, Tatsuya; Okamura, Toshimitsu; Arai, Takuya; Obata, Takayuki; Fukushi, Kiyoshi; Irie, Toshiaki; Shiraishi, Tetsuya

2010-01-01

Background and purpose: Cholinesterase inhibitors have been widely used for the treatment of patients with dementia. Monitoring of the cholinesterase activity in the blood is used as an indicator of the effect of the cholinesterase inhibitors in the brain. The selective measurement of cholinesterase with low tissue dilution is preferred for accurate monitoring; however, the methods have not been established. Here, we investigated the effect of tissue dilution on the action of cholinesterase inhibitors using a novel radiometric method with selective substrates, N-[14C]methylpiperidin-4-yl acetate ([14C]MP4A) and (R)-N-[14C]methylpiperidin-3-yl butyrate ([14C]MP3B_R), for AChE and butyrylcholinesterase (BChE) respectively. Experimental approach: We investigated the kinetics of hydrolysis of [14C]-MP4A and [14C]-MP3B_R by cholinesterases, and evaluated the selectivity of [14C]MP4A and [14C]MP3B_R for human AChE and BChE, respectively, compared with traditional substrates. Then, IC50 values of cholinesterase inhibitors in minimally diluted and highly diluted tissues were measured with [14C]MP4A and [14C]MP3B_R. Key results: AChE and BChE activities were selectively measured as the first-order hydrolysis rates of [14C]-MP4A and [14C]MP3B_R respectively. The AChE selectivity of [14C]MP4A was an order of magnitude higher than traditional substrates used for the AChE assay. The IC50 values of specific AChE and BChE inhibitors, donepezil and ethopropazine, in 1.2-fold diluted human whole blood were much higher than those in 120-fold diluted blood. In addition, the IC50 values of donepezil in monkey brain were dramatically decreased as the tissue was diluted. Conclusions and implications: This method would effectively monitor the activity of cholinesterase inhibitors used for therapeutics, pesticides and chemical warfare agents. PMID:20401964

Repeated Gestational Exposure of Mice to Chlorpyrifos Oxon Is Associated with Paraoxonase 1 (PON1) Modulated Effects in Maternal and Fetal Tissues

PubMed Central

Co, Aila L.; Hay, Ariel M.; MacDonald, James W.; Bammler, Theo K.; Farin, Federico M.; Costa, Lucio G.; Furlong, Clement E.

2014-01-01

Chlorpyrifos oxon (CPO), the toxic metabolite of the organophosphorus (OP) insecticide chlorpyrifos, causes developmental neurotoxicity in humans and rodents. CPO is hydrolyzed by paraoxonase-1 (PON1), with protection determined by PON1 levels and the human Q192R polymorphism. To examine how the Q192R polymorphism influences fetal toxicity associated with gestational CPO exposure, we measured enzyme inhibition and fetal-brain gene expression in wild-type (PON1+/+), PON1-knockout (PON1−/−), and tgHuPON1R192 and tgHuPON1Q192 transgenic mice. Pregnant mice exposed dermally to 0, 0.50, 0.75, or 0.85 mg/kg/d CPO from gestational day (GD) 6 through 17 were sacrificed on GD18. Biomarkers of CPO exposure inhibited in maternal tissues included brain acetylcholinesterase (AChE), red blood cell acylpeptide hydrolase (APH), and plasma butyrylcholinesterase (BChE) and carboxylesterase (CES). Fetal plasma BChE was inhibited in PON1−/− and tgHuPON1Q192, but not PON1+/+ or tgHuPON1R192 mice. Fetal brain AChE and plasma CES were inhibited in PON1−/− mice, but not in other genotypes. Weighted gene co-expression network analysis identified five gene modules based on clustering of the correlations among their fetal-brain expression values, allowing for correlation of module membership with the phenotypic data on enzyme inhibition. One module that correlated highly with maternal brain AChE activity had a large representation of homeobox genes. Gene set enrichment analysis revealed multiple gene sets affected by gestational CPO exposure in tgHuPON1Q192 but not tgHuPON1R192 mice, including gene sets involved in protein export, lipid metabolism, and neurotransmission. These data indicate that maternal PON1 status modulates the effects of repeated gestational CPO exposure on fetal-brain gene expression and on inhibition of both maternal and fetal biomarker enzymes. PMID:25070982

New Cholinesterase Inhibitory Constituents from Lonicera quinquelocularis

PubMed Central

Khan, Dilfaraz; Khan, Hidayat Ullah; Khan, Farmanullah; Khan, Shafiullah; Badshah, Syed; Khan, Abdul Samad; Samad, Abdul; Ali, Farman; Khan, Ihsanullah; Muhammad, Nawshad

2014-01-01

A phytochemical investigation on the ethyl acetate soluble fraction of Lonicera quinquelocularis (whole plant) led to the first time isolation of one new phthalate; bis(7-acetoxy-2-ethyl-5-methylheptyl) phthalate (3) and two new benzoates; neopentyl-4-ethoxy-3, 5-bis (3-methyl-2-butenyl benzoate (4) and neopentyl-4-hydroxy-3, 5-bis (3-methyl-2-butenyl benzoate (5) along with two known compounds bis (2-ethylhexyl phthalate (1) and dioctyl phthalate (2). Their structures were established on the basis of spectroscopic analysis and by comparison with available data in the literature. All the compounds (1–5) were tested for their acetylcholinesterase (AChE) and butyrylcholinesterase (BChE) inhibitory activities in dose dependent manner. The IC50 (50% inhibitory effect) values of compounds 3 and 5 against AChE were 1.65 and 3.43 µM while the values obtained against BChE were 5.98 and 9.84 µM respectively. Compounds 2 and 4 showed weak inhibition profile. PMID:24733024

Mycobacterium tuberculosis and cholinesterase inhibitors from Voacanga globosa.

PubMed

Macabeo, Allan Patrick G; Vidar, Warren S; Chen, Xinyu; Decker, Michael; Heilmann, Jörg; Wan, Baojie; Franzblau, Scott G; Galvez, Elano V; Aguinaldo, Ma Alicia M; Cordell, Geoffrey A

2011-07-01

Globospiramine (1), a new spirobisindole alkaloid possessing an Aspidosperma-Aspidosperma skeleton, together with deoxyvobtusine (2), deoxyvobtusine lactone (3), vobtusine lactone (4) and lupeol (5), were isolated and identified from Voacanga globosa through a bioassay-guided purification. The gross structure and absolute stereochemistry of 1 were established by circular dichroism spectroscopy, HR-MS and unambiguous NMR spectroscopic experiments. In addition, a new biogenetic pathway for the formation of the spiro-Aspidosperma-Aspidosperma skeleton is proposed. Alkaloid 1 showed potent antituberculosis activity against Mycobacterium tuberculosis H(37)Rv as evidenced in microplate Alamar blue assay (MIC = 4 μg/mL) and low-oxygen recovery assay (LORA (MIC = 5.2 μg/mL). The bisindole alkaloids also exhibited promising activity against acetylcholinesterase and, especially butyrylcholinesterase, with deoxyvobtusine (2) (IC(50) = 6.2 μM) as the most strongly inhibiting compound. This study extends the variety of alkaloid structural platforms which exhibit antimycobacterial and anticholinesterase activity. Copyright © 2011 Elsevier Masson SAS. All rights reserved.

State-wide hospital clinical laboratory plan for measuring cholinesterase activity for individuals suspected of exposure to nerve agent chemical weapons.

PubMed

Wu, Alan H B; Smith, Andrew; McComb, Robert; Bowers, George N; Makowski, Gregory S; McKay, Charles A; Vena, Jason; McDonagh, John; Hopfer, Sidney; Sena, Salvatore F; Malkus, Herbert; Forte, Elaine; Kelly, Katherine

2008-02-01

Hospital laboratories currently lack the capacity to provide emergency determination of cholinesterase activity. We have developed a hospital-based 3-tiered system to test plasma for butyrylcholinesterase (BChE) activity and whole blood for red cell acetylcholinesterase (AChE) activity using available technology and personnel. Interagency communications, toxidrome definition, and patient triage will be coordinated by the Connecticut Department of Public Health and the Poison Control Center. Initial BChE data documents good precision between institutions (coefficient of variation < 8%). Laboratory testing of plasma or blood for cholinesterase activity is important in the management of nerve agent exposure and in ruling out disease in those with non-specific symptoms in the setting of a terrorist attack or accidental exposure. Rapid availability of strong hospital-based analytic support in a smoothly functioning network of clinical, public health, and laboratory services will facilitate overall regional response to chemical terrorism or large scale HazMat events.

Anticholinesterase and Antityrosinase Activities of Ten Piper Species from Malaysia

PubMed Central

Salleh, Wan Mohd Nuzul Hakimi Wan; Hashim, Nur Athirah; Ahmad, Farediah; Heng Yen, Khong

2014-01-01

Purpose: The aim of this study was to investigate acetylcholinesterase (AChE), butyrylcholinesterase (BChE) and antityrosinase activities of extracts from ten Piper species namely; P. caninum, P. lanatum, P. abbreviatum, P. aborescens, P. porphyrophyllum, P. erecticaule, P. ribesioides, P. miniatum, P. stylosum, and P. majusculum. Methods: Anticholinesterase and antityrosinase activities were evaluated against in vitro Ellman spectroscopy method and mushroom tyrosinase, respectively. Results: The EtOAc extract of P. erecticaule showed the highest AChE and BChE inhibitory with 22.9% and 70.9% inhibition, respectively. In antityrosinase activity, all extracts of P. porphyrophyllum showed the highest inhibitory effects against mushroom tyrosinase, compared to standard, kojic acid. Conclusion: This study showed that P. erecticaule and P. porphyrophyllum have potential AChE/BChE and tyrosinase inhibition activities. The respective extracts can be explored further for the development of novel lead as AChE/BChE and tyrosinase inhibitors in therapeutic management of Alzheimer’s disease. PMID:25671185

Protective effects of aerosolized scopolamine against soman-induced acute respiratory toxicity in guinea pigs.

PubMed

Perkins, Michael W; Pierre, Zdenka; Rezk, Peter; Song, Jian; Oguntayo, Samuel; Morthole, Venee; Sciuto, Alfred M; Doctor, Bhupendra P; Nambiar, Madhusoodana P

2011-12-01

The protective efficacy of the antimuscarinic agent scopolamine was evaluated against soman (o-pinacolyl methylphosphonofluoridate [GD])-induced respiratory toxicity in guinea pigs. Anesthetized animals were exposed to GD (841 mg/m(3)) by microinstillation inhalation exposure and treated 30 seconds later with endotracheally aerosolized scopolamine (0.25 mg/kg) and allowed to recover for 24 hours. Treatment with scopolamine significantly increased survival and reduced clinical signs of toxicity and body weight loss in GD-exposed animals. Analysis of bronchoalveolar lavage (BAL) fluid showed normalization of GD-induced increased cell death, total cell count, and protein following scopolamine treatment. The BAL fluid acetylcholinesterase and butyrylcholinesterase levels were also increased by scopolamine treatment. Respiratory dynamics parameters were normalized at 4 and 24 hours post-GD exposure in scopolamine-treated animals. Lung histology showed that scopolamine treatment reduced bronchial epithelial and subepithelial inflammation and multifocal alveolar septal edema. These results suggest that aerosolized scopolamine considerably protects against GD-induced respiratory toxicity.

Arisugacins A and B, novel and selective acetylcholinesterase inhibitors from Penicillium sp. FO-4259. I. Screening, taxonomy, fermentation, isolation and biological activity.

PubMed

Kuno, F; Otoguro, K; Shiomi, K; Iwai, Y; Omura, S

1996-08-01

An in vitro screening method for selective acetylcholinesterase (AChE) inhibitors was established. Inhibitory activity of AChE and butyrylcholinesterase (BuChE) was measured and the culture broths of microorganisms that showed selective inhibition against AChE were characterized. By using this method, a strain producing the novel and selective inhibitors of AChE, arisugacins A and B, was picked out among over seven thousand microorganisms tested. Arisugacins were obtained as white powders from the culture broth together with three known compounds, territrems B and C and cyclopenin that also showed selective inhibition against AChE. Arisugacins and territrems are members of the meroterpenoid compounds. They showed potent inhibitory activities against AChE with IC50 values in range of 1.0 approximately 25.8 nM. Furthermore, they showed greater than 2,000-fold more potent inhibition against AChE than BuChE.

Delta-aminolevulinic acid dehydratase enzyme activity in blood, brain, and liver of lead-dosed ducks

USGS Publications Warehouse

Dieter, M.P.; Finley, M.T.

1979-01-01

Mallard ducks were dosed with a single shotgun pellet (ca. 200 mg lead). After 1 month there was about 1 ppm lead in blood, 2.5 in liver, and 0.5 in brain. Lead-induced inhibition of delta-aminolevulinic acid dehydratase enzyme in blood and cerebellum was much greater than in cerebral hemisphere or liver and was strongly correlated with the lead concentration in these tissues. The cerebellar portion of the brain was more sensitive to delta-aminolevulinic acid dehydratase enzyme inhibition by lead than were the other tissues examined. There was also a greater increase in the glial cell marker enzyme, butyrylcholinesterase, in cerebellum than in cerebral hemisphere, suggesting that nonregenerating neuronal cells were destroyed by lead and replaced by glial cells in that portion of the brain. Even partial loss of cerebellar tissue is severely debilitating in waterfowl, because functions critical to survival such as visual, auditory, motor, and reflex responses are integrated at this brain center.

Inhibition of Cholinesterases and Some Pro-Oxidant induced Oxidative Stress in Rats Brain by Two Tomato (Lycopersicon Esculentum) Varieties

PubMed Central

Oboh, G.; Bakare, O.O.; Ademosun, A.O.; Akinyemi, A.J.; Olasehinde, T.A.

2015-01-01

This study sought to investigate the effects of two tomato varieties [Lycopersicon esculentum Mill. var. esculentum (ESC) and Lycopersicon esculentum Mill. var. cerasiforme (CER)] on acetylcholinesterase (AChE) and butyrylcholinesterase (BChE) activities in vitro. Phenolics content, carotenoids characterisation, inhibition of Fe2+ and quinolinic acid-induced malondialdehyde (MDA) production in rats brain homogenate and NO* scavenging abilities were also assesed in addition to the AChE and BChE inhibition assays. There was no significant difference in the AChE inhibitory ability of the samples, while CER had significantly higher BChE inhibitory activity. Furthermore, the tomatoes inhibited Fe2+ and quinolinic acid-induced MDA production and further exhibited antioxidant activities through their NO* scavenging abilities. There was no significant difference in the phenolic content of the samples, while significantly high amounts of lycopene were detected in the tomatoes. The cholinesterase-inhibition and antioxidant properties of the “tomatoes” could make them good dietary means for the management of neurodegenerative disorders.

Beverages of lemon juice and exotic noni and papaya with potential for anticholinergic effects.

PubMed

Gironés-Vilaplana, Amadeo; Valentão, Patrícia; Andrade, Paula B; Ferreres, Federico; Moreno, Diego A; García-Viguera, Cristina

2015-03-01

Lemon (Citrus limon (L.) Burm. f.) juice beverages enriched either with noni (Morinda citrifolia L.) (LN) or papaya (Carica papaya L.) (LP), were characterized by HPLC-DAD-ESI/MS(n), the antioxidant capacity was evaluated by (DPPH·), superoxide (O2(·-)), hydroxyl radicals (·OH) and hypochlorous acid (HOCl) assays, and their potential as acetylcholinesterase (AChE) and butyrylcholinesterase (BuChE) inhibitors was also assessed. The fruits are rich in a wide range of bioactive phenolics. Regarding DPPH·, ·OH and HOCl assays, the LP displayed strong activity, and LN was the most active against O2(·-). Concerning cholinesterases, LP was the most active, mainly due to lemon juice contribution. The effect on the cholinesterases was not as strong as in previous reports on purified extracts, but the bioactive-rich beverages offer the possibility of dietary coadjutants for daily consumption of health-promoting substances by adults with aging-related cognitive or physical disorders. Copyright © 2014 Elsevier Ltd. All rights reserved.

Enzyme-linked DNA dendrimer nanosensors for acetylcholine

PubMed Central

Walsh, Ryan; Morales, Jennifer M.; Skipwith, Christopher G.; Ruckh, Timothy T.; Clark, Heather A.

2015-01-01

It is currently difficult to measure small dynamics of molecules in the brain with high spatial and temporal resolution while connecting them to the bigger picture of brain function. A step towards understanding the underlying neural networks of the brain is the ability to sense discrete changes of acetylcholine within a synapse. Here we show an efficient method for generating acetylcholine-detecting nanosensors based on DNA dendrimer scaffolds that incorporate butyrylcholinesterase and fluorescein in a nanoscale arrangement. These nanosensors are selective for acetylcholine and reversibly respond to levels of acetylcholine in the neurophysiological range. This DNA dendrimer architecture has the potential to overcome current obstacles to sensing in the synaptic environment, including the nanoscale size constraints of the synapse and the ability to quantify the spatio-temporal fluctuations of neurotransmitter release. By combining the control of nanosensor architecture with the strategic placement of fluorescent reporters and enzymes, this novel nanosensor platform can facilitate the development of new selective imaging tools for neuroscience. PMID:26442999

Enzyme-linked DNA dendrimer nanosensors for acetylcholine.

PubMed

Walsh, Ryan; Morales, Jennifer M; Skipwith, Christopher G; Ruckh, Timothy T; Clark, Heather A

2015-10-07

It is currently difficult to measure small dynamics of molecules in the brain with high spatial and temporal resolution while connecting them to the bigger picture of brain function. A step towards understanding the underlying neural networks of the brain is the ability to sense discrete changes of acetylcholine within a synapse. Here we show an efficient method for generating acetylcholine-detecting nanosensors based on DNA dendrimer scaffolds that incorporate butyrylcholinesterase and fluorescein in a nanoscale arrangement. These nanosensors are selective for acetylcholine and reversibly respond to levels of acetylcholine in the neurophysiological range. This DNA dendrimer architecture has the potential to overcome current obstacles to sensing in the synaptic environment, including the nanoscale size constraints of the synapse and the ability to quantify the spatio-temporal fluctuations of neurotransmitter release. By combining the control of nanosensor architecture with the strategic placement of fluorescent reporters and enzymes, this novel nanosensor platform can facilitate the development of new selective imaging tools for neuroscience.

Enzyme-linked DNA dendrimer nanosensors for acetylcholine

NASA Astrophysics Data System (ADS)

Walsh, Ryan; Morales, Jennifer M.; Skipwith, Christopher G.; Ruckh, Timothy T.; Clark, Heather A.

2015-10-01

It is currently difficult to measure small dynamics of molecules in the brain with high spatial and temporal resolution while connecting them to the bigger picture of brain function. A step towards understanding the underlying neural networks of the brain is the ability to sense discrete changes of acetylcholine within a synapse. Here we show an efficient method for generating acetylcholine-detecting nanosensors based on DNA dendrimer scaffolds that incorporate butyrylcholinesterase and fluorescein in a nanoscale arrangement. These nanosensors are selective for acetylcholine and reversibly respond to levels of acetylcholine in the neurophysiological range. This DNA dendrimer architecture has the potential to overcome current obstacles to sensing in the synaptic environment, including the nanoscale size constraints of the synapse and the ability to quantify the spatio-temporal fluctuations of neurotransmitter release. By combining the control of nanosensor architecture with the strategic placement of fluorescent reporters and enzymes, this novel nanosensor platform can facilitate the development of new selective imaging tools for neuroscience.

Synthesis and in vitro evaluation of new derivatives of 2-substituted-6-fluorobenzo[d]thiazoles as cholinesterase inhibitors.

PubMed

Imramovský, Aleš; Pejchal, Vladimír; Štěpánková, Šárka; Vorčáková, Katarína; Jampílek, Josef; Vančo, Ján; Šimůnek, Petr; Královec, Karel; Brůčková, Lenka; Mandíková, Jana; Trejtnar, František

2013-04-01

A series of novel cholinesterase inhibitors based on 2-substituted 6-fluorobenzo[d]thiazole were synthesised and characterised by IR, (1)H, (13)C and (19)F NMR spectroscopy and HRMS. Purity was checked by elemental analyses. The novel carbamates were tested for their ability to inhibit acetylcholinesterase (AChE) and butyrylcholinesterase (BChE). The toxicity of the most active compounds was investigated using a standard in vitro test with HepG2 cells, and the ratio between biological activity and toxicity was determined. In addition, the toxicity of the most active compounds was evaluated against MCF7 cells using the xCELLigence system. Structure-activity relationships reflecting the dependence of cholinesterase inhibitors on the lipophilicity of the compounds as well as on the Taft polar and steric substituent constants are discussed. The specific orientation of the inhibitors in the binding site of acetylcholinesterase was determined using molecular docking of the most active compound. Copyright © 2013 Elsevier Ltd. All rights reserved.

Efficient synthesis of novel dialkyl-3-cyanopropylphosphate derivatives and evaluation of their anticholinesterase activity.

PubMed

Aouani, Iyadh; Sellami, Badreddine; Lahbib, Karima; Cavalier, Jean-François; Touil, Soufiane

2017-06-01

Based on the broad spectrum of biological activities associated with organophosphates, a novel type of this class of compounds was synthesized, bearing a nitrile group, from the sodium alkoxide-catalyzed reaction of dialkylphosphites with γ-ketonitriles at 80°C under solvent-free conditions. A reaction mechanism involving a phospha-Brook type rearrangement is proposed. Eight title compounds were investigated for their in vitro inhibitory potency and selectivity against acetylcholinesterase (AChE) and butyrylcholinesterase (BChE) using Ellman's spectrophotometric method. The synthesized derivatives exhibited mostly a moderate activity against both cholinesterases. The IC 50 values for BChE were in a smaller concentration range (5.96-23.35µM) compared to those for AChE inhibition (9.61-53.74µM). The diethyl-3-cyano-1-p-tolylpropylphosphate which displayed the higher dual inhibitory potency towards both cholinesterases could be considered as a potential candidate for developing new drugs to treat Alzheimer's disease. Copyright © 2017 Elsevier Inc. All rights reserved.

Cholinesterase inhibitory activity and chemical constituents of Stenochlaena palustris fronds at two different stages of maturity.

PubMed

Chear, Nelson Jeng-Yeou; Khaw, Kooi-Yeong; Murugaiyah, Vikneswaran; Lai, Choon-Sheen

2016-04-01

Stenochlaena palustris fronds are popular as a vegetable in Southeast Asia. The objectives of this study were to evaluate the anticholinesterase properties and phytochemical profiles of the young and mature fronds of this plant. Both types of fronds were found to have selective inhibitory effect against butyrylcholinesterase compared with acetylcholinesterase. However, different sets of compounds were responsible for their activity. In young fronds, an antibutyrylcholinesterase effect was observed in the hexane extract, which was comprised of a variety of aliphatic hydrocarbons, fatty acids, and phytosterols. In the mature fronds, inhibitory activity was observed in the methanol extract, which contained a series of kaempferol glycosides. Our results provided novel information concerning the ability of S. palustris to inhibit cholinesterase and its phytochemical profile. Further research to investigate the potential use of this plant against Alzheimer's disease is warranted, however, young and mature fronds should be distinguished due to their phytochemical differences. Copyright © 2016. Published by Elsevier B.V.

Anticholinesterase, antioxidant activity and phytochemical investigation into aqueous extracts from five species of Agrimonia genus.

PubMed

Kubínová, Renata; Švajdlenka, Emil; Jankovská, Dagmar

2016-01-01

Aqueous extracts of aerial flowering parts of five Agrimonia species (Rosaceae): Agrimonia coreana Nakai, Agrimonia japonica (Miq.) Koidz, Agrimonia procera Wallr., Agrimonia eupatoria L. and Agrimonia leucantha Kunze were investigated on their antioxidant activity, measured using five different methods; the best was the extract from A. procera with IC50 values from 6 to 29 μg/mL. All the extracts displayed inhibition of acetylcholinesterase (AChE) and butyrylcholinesterase (BuChE) at the tested concentration of 100 μg/mL. We found the highest inhibition of cholinesterase in the extract of A. japonica with inhibition 70.4% for AChE and 79.8% for BuChE. These findings are statistically significant in comparison with those of other extracts (p < 0.001). The phytochemical analyses showed that the antioxidant activity of Agrimonia extracts can be affected especially by hexahydroxydiphenoyl (HHDP)-glucose and quercetin glycosides, and inhibition of cholinesterases by apigenin, luteolin and quercetin glycosides.

Antioxidant and Anticholinesterase Activities of Essential Oils of Cinnamomum griffithii and C. macrocarpum.

PubMed

Salleh, Wan Mohd Nuzul Hakimi; Ahmad, Farediah; Yen, Khong Heng

2015-08-01

The essential oils of Cinnamomum griffithii and C. macrocarpum were analyzed by GC and GC-MS and evaluated for their antioxidant and anticholinesterase activities. The essential oils of leaf and bark of C. grffithii were characterized by the presence of 30 components, with methyl eugenol (38.5-43.8%) as the major component. A total of 11 components were characterized in.the leaf and bark of C. macrocarpum essential oil with the most abundant component was safrole (54.5-59.5%). The bark oil of C. griffithii demonstrated significant activity on DPPH (IC50 73.4 microg/mL) and a high phenolic content (192.0%), while the leaf oil inhibited oxidation of β-carotene/linoleic acid with an inhibition value of 65.5 μg/mL. Acetylcholinesterase and butyrylcholinesterase inhibition were assessed and the results showed that C. macrocarpun bark oil exhibited significant activity with inhibition values of 55.8% and 66.1%, respectively at a concentration of 1 mg/mL.

Design, synthesis and preliminary structure-activity relationship investigation of nitrogen-containing chalcone derivatives as acetylcholinesterase and butyrylcholinesterase inhibitors: a further study based on Flavokawain B Mannich base derivatives.

PubMed

Liu, Haoran; Fan, Haoqun; Gao, Xiaohui; Huang, Xueqing; Liu, Xianjun; Liu, Linbo; Zhou, Chao; Tang, Jingjing; Wang, Qiuan; Liu, Wukun

2016-08-01

In order to study the structure-activity relationship of Flavokawain B Mannich-based derivatives as acetylcholinesterase (AChE) inhibitors in our recent investigation, 20 new nitrogen-containing chalcone derivatives (4 a-8d) were designed, synthesized, and evaluated for AChE inhibitory activity in vitro. The results suggested that amino alkyl side chain of chalcone dramatically influenced the inhibitory activity against AChE. Among them, compound 6c revealed the strongest AChE inhibitory activity (IC50 value: 0.85 μmol/L) and the highest selectivity against AChE over BuChE (ratio: 35.79). Enzyme kinetic study showed that the inhibition mechanism of compound 6c against AChE was a mixed-type inhibition. The molecular docking assay showed that this compound can both bind with the catalytic site and the peripheral site of AChE.

Chemical composition, antioxidant properties and anti-cholinesterase activity of Cordia gilletii (Boraginaceae) leaves essential oil.

PubMed

Bonesi, Marco; Okusa, Philippe N; Tundis, Rosa; Loizzo, Monica R; Menichini, Federica; Stévigny, Caroline; Duez, Pierre; Menichini, Francesco

2011-02-01

This study aimed to investigate for the first time the chemical composition, the antioxidant properties and the acetylcholinesterase (AChE) and butyrylcholinesterase (BChE) inhibitory activity of the essential oil from the leaves of Cordia gilletii De Wild (Boraginaceae). The essential oil, characterized by 23 constituents (90.1% of the total oil), was constituted by terpene derivatives (25.6%) and non-terpene derivatives (64.5%), among which aldehydes, fatty acids and alkanes were present with the percentage of 16.5%, 18.8% and 23.1%, respectively. The antioxidant activity of C. gilletii essential oil was screened by two in vitro tests: DPPH and beta-carotene bleaching test. The essential oil revealed antioxidant activity with an IC50 value of 75.0 and 129.9 microg/mL on DPPH radical and beta-carotene decoloration tests, respectively. Moreover, C. gilletii inhibited AChE enzyme with an IC50 value of 105.6 microg/mL.

Structural analysis of the asparagine-linked oligosaccharides of cholinesterases. N-linked carbohydrates of cholinesterases

DOE Office of Scientific and Technical Information (OSTI.GOV)

Saxena, A.; Doctor, B.P.

1995-12-31

Cholinesterases are serine esterases that hydrolyse choline esters faster than other substrates. They are highly glycosylated proteins with up to 24% of their molecular weight constituted of carbohydrates. Here we report the results of our studies on the glycosylation of fetal bovine serum acetylcholinesterase (FBS AChE) and horse serum butyrylcholinesterase (Eq BChE). Analysis of the monosaccharide content of the two enzymes indicated that Eq BChE contained 520 nmoles of monosaccharide/mg protein, as compared to 1290 nmoles/mg protein for Eq BChE. Both enzymes contained mannose, galactose, N-acetylglucosamine and sialic acid. Fucose was present in Eq BChE only. The structures of themore » two major oligosaccharides from FBS AChE and one major oligosaccharide from Eq BChE were determined and found to be very similar except that one of the oligosaccharides from FBS AChE contained a galactose alphal-3 galactose betal-4-determinant which has been identified as a potentially immunogenic determinant.« less

[Interest of the cholinesterase assay during organophosphate poisonings].

PubMed

Jalady, A-M; Dorandeu, F

2013-12-01

Cholinesterases are the main targets of organophosphorus compounds. The two enzymes present in the blood (butyrylcholinesterase, BChE; acetylcholinesterase, AChE) are biomarkers of their systemic toxicity. Activity of the plasma BChE is very often determined as it allows a rapid diagnostic of poisoning and is a marker of the persistence of the toxicant in the blood. The activity of the red blood cell AChE gives a better picture of the synaptic inhibition in the nervous system but the assay is less commonly available in routine laboratories. Better biomarker of the exposure, it allows a diagnosis of the severity of the poisoning and helps to assess the efficacy of oxime therapy. Besides the practical aspects of blood collection and sample processing, and the interpretation of the assays, this review stresses the complementarity of both enzyme assays and recalls their crucial interest for the confirmation of poisoning with an organophosphorus in a situation of war or terrorist attack and for the monitoring of occupational exposures. Copyright © 2013. Published by Elsevier SAS.

Cholinesterases, a target of pharmacology and toxicology.

PubMed

Pohanka, Miroslav

2011-09-01

Cholinesterases are a group of serine hydrolases that split the neurotransmitter acetylcholine (ACh) and terminate its action. Of the two types, butyrylcholinesterase and acetylcholinesterase (AChE), AChE plays the key role in ending cholinergic neurotransmission. Cholinesterase inhibitors are substances, either natural or man-made that interfere with the break-down of ACh and prolong its action. Hence their relevance to toxicology and pharmacology. The present review summarizes current knowledge of the cholinesterases and their inhibition. Particular attention is paid to the toxicology and pharmacology of cholinesterase-related inhibitors such as nerve agents (e.g. sarin, soman, tabun, VX), pesticides (e.g. paraoxon, parathion, malathion, malaoxon, carbofuran), selected plants and fungal secondary metabolites (e.g. aflatoxins), drugs for Alzheimer's disease (e.g. huperzine, metrifonate, tacrine, donepezil) and Myasthenia gravis (e.g. pyridostigmine) treatment and other compounds (propidium, ethidium, decamethonium). The crucial role of the cholinesterases in neural transmission makes them a primary target of a large number of cholinesterase-inhibiting drugs and toxins. In pharmacology, this has relevance to the treatment of neurodegenerative disorders.

Cholinesterases as biomarkers for parasympathetic dysfunction and inflammation-related disease.

PubMed

Shenhar-Tsarfaty, Shani; Berliner, Shlomo; Bornstein, Natan M; Soreq, Hermona

2014-07-01

Accumulating evidence suggests parasympathetic dysfunction and elevated inflammation as underlying processes in multiple peripheral and neurological diseases. Acetylcholine, the main parasympathetic neurotransmitter and inflammation regulator, is hydrolyzed by the two closely homologous enzymes, acetylcholinesterase and butyrylcholinesterase (AChE and BChE, respectively), which are also expressed in the serum. Here, we consider the potential value of both enzymes as possible biomarkers in diseases associated with parasympathetic malfunctioning. We cover the modulations of cholinesterase activities in inflammation-related events as well as by cholinesterase-targeted microRNAs. We further discuss epigenetic control over cholinesterase gene expression and the impact of single-nucleotide polymorphisms on the corresponding physiological and pathological processes. In particular, we focus on measurements of circulation cholinesterases as a readily quantifiable readout for changes in the sympathetic/parasympathetic balance and the implications of changes in this readout in health and disease. Taken together, this cumulative know-how calls for expanding the use of cholinesterase activity measurements for both basic research and as a clinical assessment tool.

Ferrocenylaniline based amide analogs of methoxybenzoic acids: Synthesis, structural characterization and butyrylcholinesterase (BChE) inhibition studies

NASA Astrophysics Data System (ADS)

Altaf, Ataf Ali; Kausar, Samia; Hamayun, Muhammad; Lal, Bhajan; Tahir, Muhammad Nawaz; Badshah, Amin

2017-10-01

Three new ferrocene based amides were synthesized with slight structural difference. The general formula of the amides is C5H5FeC5H4C6H4NHCOC6H4(OCH3). The synthesized compounds were characterized by instrumental techniques like elemental analysis, FTIR and NMR spectroscopy. Structure of the two compounds was also studied by single crystal X-rays diffraction analysis. Structural studies provide the evidence that pMeO (one of the synthesized compounds) is an example of amides having no intermolecular hydrogen bonding in solid structure. In the BChE inhibition assay, compound (oMeO) having strong intermolecular force in the solid structure is less active than the compound (pMeO) with weak intermolecular forces in the solid structure. The docking studies proved that hydrogen bonding between inhibitor and BChE enzyme is of more importance for the activity, rather than intermolecular hydrogen bonding in the solid structure of inhibitor.

Nippostrongylus brasiliensis: infection induces upregulation of acetylcholinesterase activity on rat intestinal epithelial cells.

PubMed

Russell, W S; Henson, S M; Hussein, A S; Tippins, J R; Selkirk, M E

2000-12-01

Expression of cholines terases and muscarinic acetylcholine receptors in the jejunal mucosa has been investigated during infection of rats with the nematode parasite Nippostrongylus brasiliensis. Selective expression of m3 receptors was observed on epithelial cells from uninfected rats and animals 7 days postinfection, and saturation binding with [(3)H]quinuclidinyl benzilate indicated that receptor expression on cell membranes was unaltered by infection. Butyrylcholinesterase was highly expressed in mucosal epithelia, but acetylcholinesterase was present at low levels in uninfected animals. In contrast, discrete foci of intense acetylcholinesterase activity were observed on the basement membrane of intestinal epithelial cells in animals infected with N. brasiliensis. This was demonstrated to be due to upregulation of expression of endogenous enzyme, which peaked at Day 10 postinfection and subsequently declined to preinfection levels. It is suggested that this occurs in response to hyper-activation of the enteric nervous system as a result of infection, and may benefit the host by limiting excessive fluid secretion due to cholinergic stimulation. Copyright 2000 Academic Press.

Contaminant concentrations, biochemical and hematological biomarkers in blood of West Indian manatees Trichechus manatus from Brazil.

PubMed

Anzolin, D G; Sarkis, J E S; Diaz, E; Soares, D G; Serrano, I L; Borges, J C G; Souto, A S; Taniguchi, S; Montone, R C; Bainy, A C D; Carvalho, P S M

2012-07-01

The West Indian manatee Trichechus manatus is threatened with extinction in Brazil, and this study focused on nondestructive blood samples analyzed for metals, polychlorinated biphenyls (PCBs) and organochlorine pesticides (OCPs), as well as biochemical and hematological biomarkers. Studied manatees were kept at Projeto Peixe-Boi headquarters in Pernambuco State, and at two natural areas in estuaries where they are released to the wild. Manatees kept at the natural estuary in Paraiba State have blood concentrations of Al, Pb, Cd, Sn that are 11, 7, 8 and 23 times greater, respectively, than the concentrations found in blood of animals from the same species in Florida, USA. An inhibition of butyrylcholinesterase in manatees kept at the two reintroduction sites in Alagoas and Paraiba States indicated possible exposure of the animals to cholinesterase inhibitor insecticides. PCBs and OCPs were not detected. Results from this study will help delineate conservation efforts in the region. Copyright © 2012 Elsevier Ltd. All rights reserved.

Bioscavengers for the protection of humans against organophosphate toxicity.

PubMed

Doctor, Bhupendra P; Saxena, Ashima

2005-12-15

Current antidotes for organophosphorus compounds (OP) poisoning consist of a combination of pretreatment with carbamates (pyridostigmine bromide), to protect acetylcholinesterase (AChE) from irreversible inhibition by OP compounds, and post-exposure therapy with anti-cholinergic drugs (atropine sulfate) to counteract the effects of excess acetylcholine and oximes (e.g., 2-PAM chloride) to reactivate OP-inhibited AChE. These antidotes are effective in preventing lethality from OP poisoning, but they do not prevent post-exposure incapacitation, convulsions, seizures, performance decrements, or in many cases permanent brain damage. These symptoms are commonly observed in experimental animals and are likely to occur in humans. The problems intrinsic to these antidotes stimulated attempts to develop a single protective drug, itself devoid of pharmacological effects, which would provide protection against the lethality of OP compounds and prevent post-exposure incapacitation. One approach is the use of enzymes such as cholinesterases (ChEs), beta-esterases in general, as single pretreatment drugs to sequester highly toxic OP anti-ChEs before they reach their physiological targets. This approach turns the irreversible nature of the OP: ChE interaction from disadvantage to an advantage; instead of focusing on OP as an anti-ChE, one can use ChE as an anti-OP. Using this approach, it was shown that administration of fetal bovine serum AChE (FBSAChE) or equine serum butyrylcholinesterase (EqBChE) or human serum BChE (HuBChE) protected the animals from multiple LD50s of a variety of highly toxic OPs without any toxic effects or performance decrements. The bioscavengers that have been explored to date for the detoxification of OPs fall into three categories: (A) those that can catalytically hydrolyze OPs and thus render them non-toxic, such as OP hydrolase and OP anhydrase; (B) those that stoichiometrically bind to OPs, that is, 1 mol of enzyme neutralizes one or 2 mol of OP inactivating both, such as ChEs and related enzymes; and (C) and those generally termed as "pseudo catalytic", e.g., a combination of ChE and an oxime pre-treatment such that the catalytic activity of OP-inhibited ChE can rapidly and continuously be restored in the presence of an oxime. Since the biochemical mechanism underlying prophylaxis by exogenous esterases such as ChEs is established and tested in several animal species, including non-human primates, this concept should allow a reliable extrapolation of results from animal experiments to human application. Having being extensively investigated by several groups, plasma derived HuBChE is judged to be the most suitable bioscavenger for its advancement for human use. The program is being developed at the present time for conducting a safety clinical trial in human volunteers. Several other candidate bioscavengers will follow; e.g., recombinant HuBChE expressed in the milk of transgenic goats, pseudo catalytic scavenger(s), e.g., a combination of ChE and oxime, and possibly PON 1 as a catalytic scavenger in the future.

QSAR, docking, dynamic simulation and quantum mechanics studies to explore the recognition properties of cholinesterase binding sites.

PubMed

Correa-Basurto, J; Bello, M; Rosales-Hernández, M C; Hernández-Rodríguez, M; Nicolás-Vázquez, I; Rojo-Domínguez, A; Trujillo-Ferrara, J G; Miranda, René; Flores-Sandoval, C A

2014-02-25

A set of 84 known N-aryl-monosubstituted derivatives (42 amides: series 1 and 2, and 42 imides: series 3 an 4, from maleic and succinic anhydrides, respectively) that display inhibitory activity toward both acetylcholinesterase and butyrylcholinesterase (ChEs) was considered for Quantitative structure-activity relationship (QSAR) studies. These QSAR studies employed docking data from both ChEs that were previously submitted to molecular dynamics (MD) simulations. Donepezil and galanthamine stereoisomers were included to analyze their quantum mechanics properties and for validating the docking procedure. Quantum parameters such as frontier orbital energies, dipole moment, molecular volume, atomic charges, bond length and reactivity parameters were measured, as well as partition coefficients, molar refractivity and polarizability were also analyzed. In order to evaluate the obtained equations, four compounds: 1a (4-oxo-4-(phenylamino)butanoic acid), 2a ((2Z)-4-oxo-4-(phenylamino)but-2-enoic acid), 3a (2-phenylcyclopentane-1,3-dione) and 4a (2-phenylcyclopent-4-ene-1,3-dione) were employed as independent data set, using only equations with r(m(test))²>0.5. It was observed that residual values gave low value in almost all series, excepting in series 1 for compounds 3a and 4a, and in series 4 for compounds 1a, 2a and 3a, giving a low value for 4a. Consequently, equations seems to be specific according to the structure of the evaluated compound, that means, series 1 fits better for compound 1a, series 3 or 4 fits better for compounds 3a or 4a. Same behavior was observed in the butyrylcholinesterase (BChE). Therefore, obtained equations in this QSAR study could be employed to calculate the inhibition constant (Ki) value for compounds having a similar structure as N-aryl derivatives described here. The QSAR study showed that bond lengths, molecular electrostatic potential and frontier orbital energies are important in both ChE targets. Docking studies revealed that despite the multiple conformations obtained through MD simulations on both ChEs, the ligand recognition properties were conserved. In fact, the complex formed between ChEs and the best N-aryl compound reproduced the binding mode experimentally reported, where the ligand was coupled into the choline-binding site and stabilized through π-π interactions with Trp82 or Trp86 for BChE and AChE, respectively, suggesting that this compound could be an efficient inhibitor and supporting our model. Copyright © 2014. Published by Elsevier Ireland Ltd.

The proof-of-concept of ASS234: Peripherally administered ASS234 enters the central nervous system and reduces pathology in a male mouse model of Alzheimer disease

PubMed Central

Serrano, Mari Paz; Herrero-Labrador, Raquel; Futch, Hunter S.; Serrano, Julia; Romero, Alejandro; Fernandez, Ana Patricia; Samadi, Abdelouahid; Unzeta, Mercedes; Marco-Contelles, Jose; Martínez-Murillo, Ricardo

2017-01-01

Background The heterogeneity of Alzheimer disease requires the development of multitarget drugs for treating the symptoms of the disease and its progression. Both cholinergic and monoamine oxidase dysfunctions are involved in the pathological process. Thus, we hypothesized that the development of therapies focused on these targets might be effective. We have developed and assessed a new product, coded ASS234, a multipotent acetyl and butyrylcholinesterase/monoamine oxidase A–B inhibitor with a potent inhibitory effect on amyloid-β aggregation as well as antioxidant and antiapoptotic properties. But there is a need to reliably correlate in vitro and in vivo drug release data. Methods We examined the effect of ASS234 on cognition in healthy adult C57BL/6J mice in a model of scopolamine-induced cognitive impairment that often accompanies normal and pathological aging. Also, in a characterized transgenic APPswe/PS1ΔE9 mouse model of Alzheimer disease, we examined the effects of short-term ASS234 treatment on plaque deposition and gliosis using immunohistochemistry. Toxicology of ASS234 was assessed using a quantitative high-throughput in vitro cytotoxicity screening assay following the MTT assay method in HepG2 liver cells. Results In vivo, ASS234 significantly decreased scopolamine-induced learning deficits in C57BL/6J mice. Also, reduction of amyloid plaque burden and gliosis in the cortex and hippocampus was assessed. In vitro, ASS234 exhibited lesser toxicity than donepezil and tacrine. Limitations The study was conducted in male mice only. Although the Alzheimer disease model does not recapitulate all features of the human disease, it exhibits progressive monoaminergic neurodegeneration. Conclusion ASS234 is a promising alternative drug of choice to treat the cognitive decline and neurodegeneration underlying Alzheimer disease. PMID:27636528

Cholinesterase inhibitory activities of Apai-sa-le recipe and its ingredients.

PubMed

Senavong, Pimolvan; Sattaponpan, Chitsanucha; Silavat Suk-um; Itharat, Arunporn

2014-08-01

Acetylcholinesterase and butyrylcholoinesterase inhibitors are well-known drugs commonly used in the treatment ofAlzheimer's disease (AD) to improve cognitive function. These enzyme inhibitors were reported to be found in manyplants. Apai-sa-le recipe was a Thai tradition used as nootropic recipe and formerly claimed to improve memory. Therefore, it is interesting to investigate cholinesterase inhibitory activity ofthe recipe and its ingredients. To determine the whole recipe ofApai-sa-le and its ingredients for inhibitory effect on acetylcholinesterase (AChE) and human butyrylcholinesterase (BuChE) activities. Thirty grams of each plant and 181 grams of the whole recipe were separately extracted by 95% ethanol, after filtered the filtrate were evaporated and vacuum-dried at 45°C. By Elman method, the inhibitory activities of both enzymes were assessed. The volatile constituents ofeach extract were determined by GCMS. The constituents in the non- volatile extract were examined by TLC and the antioxidant activity was determined. Four plants exhibited specific BuChE inhibitor were Lepidium sativum Linn. (Ls), Piper nigrum L. (Pn), Angelica dahurica Benth (Ad) andAtractylodes lancea DC. (Al), which shown the lC50 of 5.59, 24.52, 73.23, 96.25 μg/ml, respectively whereas galantamine and the whole recipe showed IC50 of 0.59 and 236 μg/ml. Only Pn extract inhibited AChE at lCso of 25.46 μg/ml. By GCMS and TLC fingerprints revealed the main constituents in LS, Ad, Al andPn as apiol, cumialdehyde, furanodiene and piperine. Moreover nine plant extracts and the whole recipe showed antioxidant activity. Lepidium sativum Linn. (Ls) extract showed the most potency on BuChE inhibitory effect. Three ingredients and the whole recipe exhibited mild activity. Only Piper nigrum L demonstrated inhibition effect on both AChE and BuChE.

Acute administration of tramadol and tapentadol at effective analgesic and maximum tolerated doses causes hepato- and nephrotoxic effects in Wistar rats.

PubMed

Barbosa, Joana; Faria, Juliana; Leal, Sandra; Afonso, Luís Pedro; Lobo, João; Queirós, Odília; Moreira, Roxana; Carvalho, Félix; Dinis-Oliveira, Ricardo Jorge

2017-08-15

Tramadol and tapentadol are two atypical synthetic opioid analgesics, with monoamine reuptake inhibition properties. Mainly aimed at the treatment of moderate to severe pain, these drugs are extensively prescribed for multiple clinical applications. Along with the increase in their use, there has been an increment in their abuse, and consequently in the reported number of adverse reactions and intoxications. However, little is known about their mechanisms of toxicity. In this study, we have analyzed the in vivo toxicological effects in liver and kidney resulting from an acute exposure of a rodent animal model to both opioids. Male Wistar rats were intraperitoneally administered with 10, 25 and 50mg/kg tramadol and tapentadol, corresponding to a low, effective analgesic dose, an intermediate dose and the maximum recommended daily dose, respectively, for 24h. Toxicological effects were assessed in terms of oxidative stress, biochemical and metabolic parameters and histopathology, using serum and urine samples, liver and kidney homogenates and tissue specimens. The acute exposure to tapentadol caused a dose-dependent increase in protein oxidation in liver and kidney. Additionally, exposure to both opioids led to hepatic commitment, as shown by increased serum lipid levels, decreased urea concentration, increased alanine aminotransferase and decreased butyrylcholinesterase activities. It also led to renal impairment, as reflected by proteinuria and decreased glomerular filtration rate. Histopathological findings included sinusoidal dilatation, microsteatosis, vacuolization, cell infiltrates and cell degeneration, indicating metabolic changes, inflammation and cell damage. In conclusion, a single effective analgesic dose or the maximum recommended daily dose of both opioids leads to hepatotoxicity and nephrotoxicity, with tapentadol inducing comparatively more toxicity. Whether these effects reflect risks during the therapeutic use or human overdoses requires focused attention by the medical community. Copyright © 2017 Elsevier B.V. All rights reserved.

Preparation, characterization of Fe3O4 at TiO2 magnetic nanoparticles and their application for immunoassay of biomarker of exposure to organophosphorus pesticides

DOE Office of Scientific and Technical Information (OSTI.GOV)

Zhang, Xiao; Wang, Hongbo; Yang, Chunming

2013-03-15

Novel Fe3O4 at TiO2 magnetic nanoparticles were prepared and developed for a new nanoparticle-based immunosensor for electrochemical quantification of organophosphorylated butyrylcholinesterase (BChE) in plasma, a specific biomarker of exposure to organophosphorus (OP) agents. The Fe3O4 at TiO2 nanoparticles were synthesized by hydrolysis of tetrabutyltitanate on the surface of Fe3O4 magnetic nanospheres, and characterized by attenuated total reflection Fourier-transform infrared spectra, transmission electron microscope and X-ray diffraction. The functional Fe3O4 at TiO2 nanoparticles were performed as capture antibody to selectively enrich phosphorylated moiety instead of phosphoserine antibody in the traditional sandwich immunoassays. The secondary recognition was served by quantum dots (QDs)-taggedmore » anti-BChE antibody (QDs-anti-BChE). With the help of a magnet, the resulting sandwich-like complex, Fe3O4 at TiO2/OP-BChE/QDs-anti-BChE, was easily isolated from sample solutions and the released cadmium ions were detected on a disposable screen-printed electrode (SPE). The binding affinities were investigated by both surface plasmon resonance (SPR) and square wave voltammetry (SWV). This method not only avoids the drawback of unavailability of commercial OP-specific antibody but also amplifies detection signal by QDs-tags together with easy separation of samples by magnetic forces. The proposed immunosensor yields a linear response over a broad OP-BChE concentrations range from 0.02 to 10 nM, with detection limit of 0.01 nM. Moreover, the disposable nanoparticle-based immunosensor has been validated with human plasma samples. It offers a new method for rapid, sensitive, selective and inexpensive screening/evaluating exposure to OP pesticides.« less

A High-Throughput Enzyme Assay for Organophosphate Residues in Milk

PubMed Central

Mishra, Rupesh K.; Deshpande, Kanchanmala; Bhand, Sunil

2010-01-01

A rapid, high-sensitivity, chemiluminescence (CL) enzyme assay for the determination of organophosphate (OP) residues in milk is presented. The assay for quantification of OP residues in milk is based on the inhibition of enzyme butyrylcholinesterase (BuChE). BuChE was stabilized and preloaded in 384 well plates at 30 °C. The assay permits rapid determination of OPs in milk within 12 min including an incubation step. The enzyme assay was tested for individual and mixtures of OPs such as methyl paraoxon (MPOx), methyl parathion (MP) and malathion (MT) in milk to evaluate their synergistic effect on BuChE inhibition. Good linearity was obtained in the range 0.005–50 μg·L−1 for MPOx and 0.5–1,000 μg·L−1 for MP as well as MT in milk. Mean recovery of 93.2%–98.6% was obtained for MPOx spiked milk samples with 0.99%–1.67% reproducibility (RSD). The proposed method facilitated rapid screening of milk samples in 384 well plate formats with further miniaturization presented in 1,536 well plates. PMID:22163525

Radiolabeled cycloSaligenyl Monophosphates of 5-Iodo-2′-deoxyuridine, 5-Iodo-3′-fluoro-2′, 3′-dideoxyuridine, and 3′-Fluorothymidine for Molecular Radiotherapy of Cancer: Synthesis and Biological Evaluation

PubMed Central

Kortylewicz, Zbigniew P.; Kimura, Yu; Inoue, Kotaro; Mack, Elizabeth; Baranowska-Kortylewicz, Janina

2012-01-01

Targeted molecular radiotherapy opens unprecedented opportunities to eradicate cancer cells with minimal irradiation of normal tissues. Described in this study are radioactive cycloSaligenyl monophosphates designed to deliver lethal doses of radiation to cancer cells. These compounds can be radiolabeled with SPECT- and PET-compatible radionuclides as well as radionuclides suitable for Auger electron therapies. This characteristic provides an avenue for the personalized and comprehensive treatment strategy that comprises diagnostic imaging to identify sites of disease, followed by the targeted molecular radiotherapy based on the imaging results. The developed radiosynthetic methods produce no-carrier-added products with high radiochemical yield and purity. The interaction of these compounds with their target, butyrylcholinesterase, depends on the stereochemistry around the P atom. IC50 values are in the nM range. In vitro studies indicate that radiation doses delivered to the cell nucleus are sufficient to kill cells of several difficult to treat malignancies including glioblastoma, and ovarian and colorectal cancers. PMID:22339166

Novel multipotent phenylthiazole-tacrine hybrids for the inhibition of cholinesterase activity, β-amyloid aggregation and Ca²⁺ overload.

PubMed

Wang, Yue; Wang, Fang; Yu, Jun-Ping; Jiang, Feng-Chao; Guan, Xin-Lei; Wang, Can-Ming; Li, Lei; Cao, Hui; Li, Ming-Xing; Chen, Jian-Guo

2012-11-01

In this study, a series of multipotent phenylthiazole-tacrine hybrids (7a-7e, 8, and 9a-9m) were synthesized and biologically evaluated. Screening results showed that phenylthiazole-tacrine hybrids were potent cholinesterase inhibitors with pIC(50) (-logIC(50)) value ranging from 5.78 ± 0.05 to 7.14 ± 0.01 for acetylcholinesterase (AChE), and from 5.75 ± 0.03 to 10.35 ± 0.15 for butyrylcholinesterase (BuChE). The second series of phenylthiazole-tacrine hybrids (9a-9m) could efficiently prevent Aβ(1-42) self-aggregation. The structure-activity relationship revealed that their inhibitory potency relied on the type of middle linker and substitutions at 4'-position of 4-phenyl-2-aminothiazole. In addition, 7a and 7c also displayed the Ca(2+) overload blockade effect in the primary cultured cortical neurons. Consequently, these compounds emerged as promising molecules for the therapy of Alzheimer's disease. Copyright © 2012 Elsevier Ltd. All rights reserved.

Evaluation of anti-cholinesterase, antibacterial and cytotoxic activities of green synthesized silver nanoparticles using from Millettia pinnata flower extract.

PubMed

Rajakumar, Govindasamy; Gomathi, Thandapani; Thiruvengadam, Muthu; Devi Rajeswari, V; Kalpana, V N; Chung, Ill-Min

2017-02-01

The aim of this study is to develop an easy and eco-friendly method for the synthesis of Ag-NPs using extracts from the medicinal plant, Millettia pinnata flower extract and investigate the effects of Ag-NPs on acetylcholinesterase (AChE), butyrylcholinesterase (BChE), antibacterial and cytotoxicity activity. UV-Vis peak at 438 nm confirmed the Ag-NPs absorbance. The SEM analysis results confirmed the presence of spherical shaped Ag-NPs by a huge disparity in the particle size distribution with an average size of 49 ± 0.9 nm. TEM images revealed the formation of Ag-NPs with spherical shape and sizes in the range between 16 and 38 nm. The Ag-NPs showed an excellent inhibitory efficacy against AChE and BChE. The highest antibacterial activity was found against Escherichia coli (20.25 ± 0.91 mm). These nanoparticles showed the cytotoxic effects against brine shrimp (artemia saliana) nauplii with a LD 50 value of 33.92. Copyright © 2016 Elsevier Ltd. All rights reserved.

Insights into cholinesterase inhibitory and antioxidant activities of five Juniperus species.

PubMed

Orhan, Nilufer; Orhan, Ilkay Erdogan; Ergun, Fatma

2011-09-01

In vitro acetylcholinesterase (AChE) and butyrylcholinesterase (BChE) inhibitory and antioxidant activities of the aqueous and ethanol extracts of the leaves, ripe fruits, and unripe fruits of Juniperus communis ssp. nana, Juniperus oxycedrus ssp. oxycedrus, Juniperus sabina, Juniperus foetidissima, and Juniperus excelsa were investigated in the present study. Cholinesterase inhibition of the extracts was screened using ELISA microplate reader. Antioxidant activity of the extracts was tested by 2,2-diphenyl-1-picrylhydrazyl (DPPH) and superoxide radical scavenging, ferrous ion-chelating, and ferric-reducing antioxidant power (FRAP) assays. Total phenol and flavonoid contents of the extracts were determined spectrophotometrically. The extracts had low or no inhibition towards AChE, whereas the leaf aqueous extract of J. foetidissima showed the highest BChE inhibition (93.94 ± 0.01%). The leaf extracts usually exerted higher antioxidant activity. We herein describe the first study on anticholinesterase and antioxidant activity by the methods of ferrous ion-chelating, superoxide radical scavenging, and ferric-reducing antioxidant power (FRAP) assays of the mentioned Juniperus species. Copyright © 2011 Elsevier Ltd. All rights reserved.

Mannich-Benzimidazole Derivatives as Antioxidant and Anticholinesterase Inhibitors: Synthesis, Biological Evaluations, and Molecular Docking Study.

PubMed

Alpan, Ayşe Selcen; Sarıkaya, Görkem; Çoban, Güneş; Parlar, Sülünay; Armagan, Güliz; Alptüzün, Vildan

2017-07-01

A series of Mannich bases of benzimidazole derivatives having a phenolic group were designed to assess their anticholinesterase and antioxidant activities. The acetylcholinesterase (AChE) and butyrylcholinesterase (BuChE) inhibitory activities were evaluated in vitro by using Ellman's method. According to the activity results, all of the compounds exhibited moderate to good AChE inhibitory activity (except for 2a), with IC 50 values ranging from 0.93 to 10.85 μM, and generally displayed moderate BuChE inhibitory activity. Also, most of the compounds were selective against BuChE. Compound 4b was the most active molecule on the AChE enzyme and also selective. In addition, we investigated the antioxidant effects of the synthesized compounds against FeCl 2 /ascorbic acid-induced oxidative stress in the rat brain in vitro, and the activity results showed that most of the compounds are effective as radical scavengers. Molecular docking studies and molecular dynamics simulations were also carried out. © 2017 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

Design, synthesis and biological evaluation of multifunctional tacrine-curcumin hybrids as new cholinesterase inhibitors with metal ions-chelating and neuroprotective property.

PubMed

Liu, Zhikun; Fang, Lei; Zhang, Huan; Gou, Shaohua; Chen, Li

2017-04-15

Total sixteen tacrine-curcumin hybrid compounds were designed and synthesized for the purpose of searching for multifunctional anti-Alzheimer agents. In vitro studies showed that these hybrid compounds showed good cholinesterase inhibitory activity. Particularly, the potency of K 3-2 is even beyond tacrine. Some of the compounds exhibited different selectivity on acetylcholinesterase or butyrylcholinesterase due to the structural difference. Thus, the structure and activity relationship is summarized and further discussed based on molecular modeling studies. The ORAC and MTT assays indicated that the hybrid compounds possessed pronounced antioxidant activity and could effectively protect PC12 cells from the H 2 O 2 /Aβ42-induced toxicity. Moreover, the hybrid compounds also showed positive metal ions-chelating ability in vitro, suggesting a potential to halt ion-induced Aβ aggregation. All the obtained results demonstrated that the tacrine-curcumin hybrid compounds, in particular compound K 3-2 , can be considered as potential therapeutic agents for Alzheimer's disease. Copyright © 2017 Elsevier Ltd. All rights reserved.

Natural cholinesterase inhibitors from Myristica cinnamomea King.

PubMed

Abdul Wahab, Siti Mariam; Sivasothy, Yasodha; Liew, Sook Yee; Litaudon, Marc; Mohamad, Jamaludin; Awang, Khalijah

2016-08-01

A new acylphenol, malabaricone E (1) together with the known malabaricones A-C (2-4), maingayones A and B (5 and 6) and maingayic acid B (7) were isolated from the ethyl acetate extract of the fruits of Myristica cinnamomea King. Their structures were determined by 1D and 2D NMR techniques and LCMS-IT-TOF analysis. Compounds 3 (1.84±0.19 and 1.76±0.21μM, respectively) and 4 (1.94±0.27 and 2.80±0.49μM, respectively) were identified as dual inhibitors, with almost equal acetylcholinesterase (AChE) and butyrylcholinesterase (BChE) enzymes inhibiting potentials. The Lineweaver-Burk plots of compounds 3 and 4 indicated that they were mixed-mode inhibitors. Based on the molecular docking studies, compounds 3 and 4 interacted with the peripheral anionic site (PAS), the catalytic triad and the oxyanion hole of the AChE. As for the BChE, while compound 3 interacted with the PAS, the catalytic triad and the oxyanion hole, compound 4 only interacted with the catalytic triad and the oxyanion hole. Copyright © 2016 Elsevier Ltd. All rights reserved.

Evaluation of Antioxidant, Anticholinesterase, and Antidiabetic Potential of Dry Leaves and Stems in Tamarix aphylla Growing Wild in Tunisia.

PubMed

Mahfoudhi, Adel; Grosso, Clara; Gonçalves, Rui F; Khelifi, Eltaief; Hammami, Saoussen; Achour, Sami; Trabelsi-Ayadi, Malika; Valentão, Patrícia; Andrade, Paula B; Mighri, Zine

2016-12-01

Tamarix aphylla (L.) Karst. has a wide geographic distribution and was employed in traditional medicine as astringent, anti-rheumatic and to treat fever. T. aphylla leaves and stems extracts were studied from both chemical and biological points of view to assess the antidiabetic, anticholinesterase and antioxidant potential of this species. The HPLC/Diode Array Detector (DAD) analysis showed the presence of 14 phenolic compounds (gallic, caffeic, p-coumaric, ferulic and ellagic acids, kaempferol, quercetin, quercetin 3-O-galactoside and six flavonol derivatives). This is the first study reporting a comparative study of the biological activities of different extracts from T. aphylla. High activities were obtained against DPPH radical, superoxide anion radical (O2∙-) and nitric oxide radical ( • NO) in a concentration-dependent manner, the most active extracts being the polar ones. T. aphylla also showed moderate protective effects against acetylcholinesterase, but no effects were observed against butyrylcholinesterase. Against α-glucosidase the MeOH extracts displayed IC 50 values from 8.41 to 24.81 μg/ml. © 2016 Wiley-VHCA AG, Zurich, Switzerland.

Capsofulvesins A-C, cholinesterase inhibitors from Capsosiphon fulvescens.

PubMed

Fang, Zhe; Yang Jeong, Su; Ah Jung, Hyun; Sue Choi, Jae; Sun Min, Byung; Hee Woo, Mi

2012-01-01

Activity-directed isolation of the n-hexane and dichloromethane fractions of Capsosiphon fulvescens resulted in the identification of four new glycolipids (1-3): (2S)-1-O-(6Z,9Z,12Z,15Z-octadecatetraenoyl)-2-O-(4Z,7Z,10Z,13Z-hexadecatetraenoyl)-3-O-β-D-galactopyranosyl glycerol (1, capsofulvesin A), (2S)-l-O-(9Z,12Z,15Z-octadecatrienoyl)-2-O-(10Z,13Z-hexadecadienoyl)-3-O-β-D-galactopyranosyl glycerol (2, capsofulvesin B), (2S)-1-O-(6Z,9Z,12Z,15Z-octadecatetraenoyl)-3-O-β-D-galacatopyranosyl glycerol (3, capsofulvesin C). Compounds 1-6 exhibited acetylcholinesterase (AChE) inhibitory activities with IC(50) values ranging from 50.90 to 82.83 µM, whereas 2-6 showed butyrylcholinesterase (BChE) inhibitory activities with IC(50) values of 114.75-185.55 µM. Although most of the compounds isolated lacked scavenging activity for 1,1-diphenyl-2-picrylhydrazyl (DPPH) radical and peroxynitrite (ONOO(-)), compound 8 showed ONOO(-) scavenging activity with an IC(50) value of 26.23 µg/mL.

Alkaloid profiling and anticholinesterase activity of South American Lycopodiaceae species.

PubMed

Konrath, Eduardo Luis; Ortega, María Gabriela; de Loreto Bordignon, Sérgio; Apel, Miriam Anders; Henriques, Amélia Teresinha; Cabrera, José Luis

2013-02-01

The alkaloid extracts of four Huperzia and one Lycopodiella species, from Brazilian habitats, were tested for their in vitro anticholinesterase activities. IC(50) values showed a potent acetylcholinesterase inhibition for H. reflexa (0.11 ± 0.05 μg/mL), followed by H. quadrifariata (2.0 ± 0.3 μg/mL), H. acerosa (5.5 ± 0.9 μg/mL), H. heterocarpon (25.6 ± 2.7 μg/mL) and L. cernua (42.6 ± 1.5 μg/mL). A lower inhibition of butyrylcholinesterase was observed for all species with the exception of H. heterocarpon (8.3 ± 0.9 μg/mL), whose alkaloid extract presented a selectivity for pseudocholinesterase. Moreover, the chemical study of the bioactive extracts performed by GC-MS, revealed the presence of a number of Lycopodium alkaloids belonging to the lycopodane, flabellidane and cernuane groups. Surprisingly, the potent acetylcholinesterase inhibitors huperzines A and B were not detected in the extracts, suggesting that other alkaloids may be responsible for such an effect.

Antioxidant and cholinesterase inhibitory activity of a new peptide from Ziziphus jujuba fruits.

PubMed

Zare-Zardini, Hadi; Tolueinia, Behnaz; Hashemi, Azam; Ebrahimi, Leila; Fesahat, Farzaneh

2013-11-01

Antioxidant agents and cholinesterase inhibitors are the foremost drugs for the treatment of Alzheimer's disease (AD). In this study, a new peptide from Ziziphus jujuba fruits was investigated for its inhibitory activity against acetylcholinesterase (AChE) and butyrylcholinesterase (BChE) enzymes as well as antioxidant activity. This peptide was introduced as a new peptide and named Snakin-Z. The Snakin-Z displayed considerable cholinesterase inhibition against AChE and BChE. The half maximal inhibitory concentration (IC50) values of Snakin-Z against AChE and BChE are 0.58 ± 0.08 and 0.72 ± 0.085 mg/mL, respectively. This peptide has 80% enzyme inhibitory activity on AChE and BChE at 1.5 mg/mL. The Snakin-Z also had the high antioxidant activity (IC50 = 0.75 ± 0.09 mg/mL). Thus, it is suggested that Snakin-Z may be beneficial in the treatment of AD. However, more detailed researches are still required as in vivo testing its anticholinesterase and antioxidant activities.

Effect-directed analysis via hyphenated high-performance thin-layer chromatography for bioanalytical profiling of sunflower leaves.

PubMed

Móricz, Ágnes M; Ott, Péter G; Yüce, Imanuel; Darcsi, András; Béni, Szabolcs; Morlock, Gertrud E

2018-01-19

High-performance thin-layer chromatography (HPTLC) coupled with effect-directed analysis was used for non-targeted screening of sunflower leaf extract for components exhibiting antioxidant, antibacterial and/or cholinesterase enzyme inhibitory effects. The active compounds were characterized by HPTLC-electrospray ionization-high resolution mass spectrometry (ESI-HRMS) and HPTLC-Direct Analysis in Real Time (DART)-MS/MS. The latter ambient ionization technique (less soft than ESI) resulted in oxidation and fragmentation products and characteristic fragment ions. NMR spectroscopy after targeted isolation via preparative normal phase flash chromatography and semi-preparative reversed phase high-performance liquid chromatography supported the identification of two diterpenes to be (-)-kaur-16-en-19-oic acid and 15-α-angeloyloxy-ent-kaur-16-en-19-oic acid. Both compounds found to be multi-potent as they inhibited acetylcholinesterase and butyrylcholinesterase and showed antibacterial effects against Gram-positive Bacillus subtilis and Gram-negative Aliivibrio fischeri bacteria. Kaurenoic acid was also active against the Gram-negative pepper pathogenic Xanthomonas euvesicatoria bacteria. Copyright © 2017 Elsevier B.V. All rights reserved.

Suitability of cholinesterase of polychaete Diopatra neapolitana as biomarker of exposure to pesticides: In vitro characterization.

PubMed

Mennillo, Elvira; Casu, Valentina; Tardelli, Federica; De Marchi, Lucia; Freitas, Rosa; Pretti, Carlo

2017-01-01

Cholinesterases of Diopatra neapolitana were characterized for their activity in whole body and different body segments (apical, intermediate, posterior), substrate affinity (acetyl-, butyryl-, propionylthiocholine), kinetic parameters (K m and V max ) and in vitro response to model inhibitors (eserine hemisulfate, isoOMPA, BW284C51) and carbamates (carbofuran, methomyl, aldicarb and carbaryl). Results showed that the rate of hydrolysis for acetyl- and propionylthiocholine was higher in the posterior segment than the apical/intermediate segments and whole body. Cholinesterases of D. neapolitana showed a substrate preference for acetylthiocholine followed by propionylthiocholine; butyrylthioline was poorly hydrolyzed indicating, together with the absence of inhibition by the specific inhibitor and the absence of reactive bands in native electrophoresis, a lack of an active butyrylcholinesterase, differently than that observed in other Annelida species. The degree of inhibition by selected carbamates of cholinesterase activity with propionylthiocholine as substrate was higher than that observed with ATChI-ChE activity; aldicarb showed the highest inhibitory effect. Copyright © 2016 Elsevier Inc. All rights reserved.

Quantitative estimation of cholinesterase-specific drug metabolism of carbamate inhibitors provided by the analysis of the area under the inhibition-time curve.

PubMed

Zhou, Huimin; Xiao, Qiaoling; Tan, Wen; Zhan, Yiyi; Pistolozzi, Marco

2017-09-10

Several molecules containing carbamate groups are metabolized by cholinesterases. This metabolism includes a time-dependent catalytic step which temporary inhibits the enzymes. In this paper we demonstrate that the analysis of the area under the inhibition versus time curve (AUIC) can be used to obtain a quantitative estimation of the amount of carbamate metabolized by the enzyme. (R)-bambuterol monocarbamate and plasma butyrylcholinesterase were used as model carbamate-cholinesterase system. The inhibition of different concentrations of the enzyme was monitored for 5h upon incubation with different concentrations of carbamate and the resulting AUICs were analyzed. The amount of carbamate metabolized could be estimated with <15% accuracy (RE%) and ≤23% precision (RSD%). Since the knowledge of the inhibition kinetics is not required for the analysis, this approach could be used to determine the amount of drug metabolized by cholinesterases in a selected compartment in which the cholinesterase is confined (e.g. in vitro solutions, tissues or body fluids), either in vitro or in vivo. Copyright © 2017 Elsevier B.V. All rights reserved.

Structure-Based Design and Optimization of Multitarget-Directed 2H-Chromen-2-one Derivatives as Potent Inhibitors of Monoamine Oxidase B and Cholinesterases.

PubMed

Farina, Roberta; Pisani, Leonardo; Catto, Marco; Nicolotti, Orazio; Gadaleta, Domenico; Denora, Nunzio; Soto-Otero, Ramon; Mendez-Alvarez, Estefania; Passos, Carolina S; Muncipinto, Giovanni; Altomare, Cosimo D; Nurisso, Alessandra; Carrupt, Pierre-Alain; Carotti, Angelo

2015-07-23

The multifactorial nature of Alzheimer's disease calls for the development of multitarget agents addressing key pathogenic processes. To this end, by following a docking-assisted hybridization strategy, a number of aminocoumarins were designed, prepared, and tested as monoamine oxidases (MAOs) and acetyl- and butyryl-cholinesterase (AChE and BChE) inhibitors. Highly flexible N-benzyl-N-alkyloxy coumarins 2-12 showed good inhibitory activities at MAO-B, AChE, and BChE but low selectivity. More rigid inhibitors, bearing meta- and para-xylyl linkers, displayed good inhibitory activities and high MAO-B selectivity. Compounds 21, 24, 37, and 39, the last two featuring an improved hydrophilic/lipophilic balance, exhibited excellent activity profiles with nanomolar inhibitory potency toward hMAO-B, high hMAO-B over hMAO-A selectivity and submicromolar potency at hAChE. Cell-based assays of BBB permeation, neurotoxicity, and neuroprotection supported the potential of compound 37 as a BBB-permeant neuroprotective agent against H2O2-induced oxidative stress with poor interaction as P-gp substrate and very low cytotoxicity.

Chemical profiling analysis of Maca using UHPLC-ESI-Orbitrap MS coupled with UHPLC-ESI-QqQ MS and the neuroprotective study on its active ingredients

NASA Astrophysics Data System (ADS)

Zhou, Yanyan; Li, Peng; Brantner, Adelheid; Wang, Hongjie; Shu, Xinbin; Yang, Jian; Si, Nan; Han, Lingyu; Zhao, Haiyu; Bian, Baolin

2017-03-01

Lepidium meyenii (Maca), originated from Peru, has been cultivated widely in China as a popular health care food. However, the chemical and effective studies of Maca were less in-depth, which restricted its application seriously. To ensure the quality of Maca, a feasible and accurate strategy was established. One hundred and sixty compounds including 30 reference standards were identified in 6 fractions of methanol extract of Maca by UHPLC-ESI-Orbitrap MS. Among them, 15 representative active compounds were simultaneously determined in 17 samples by UHPLC-ESI-QqQ MS. The results suggested that Maca from Yunnan province was the potential substitute for the one from Peru. Meanwhile, the neuroprotective effects of Maca were investigated. Three fractions and two pure compounds showed strong activities in the 1-methyl-4-phenyl-1, 2, 3, 6-tetrahydropyridine (MPTP)-induced zebrafish model. Among them, 80% methanol elution fraction (Fr5) showed significant neuroprotective activity, followed by 100% part (Fr6). The inhibition of acetylcholinesterase (AChE) and butyrylcholinesterase (BuChE) was a possible mechanism of its neuroprotective effect.

Chemical profiling analysis of Maca using UHPLC-ESI-Orbitrap MS coupled with UHPLC-ESI-QqQ MS and the neuroprotective study on its active ingredients

PubMed Central

Zhou, Yanyan; Li, Peng; Brantner, Adelheid; Wang, Hongjie; Shu, Xinbin; Yang, Jian; Si, Nan; Han, Lingyu; Zhao, Haiyu; Bian, Baolin

2017-01-01

Lepidium meyenii (Maca), originated from Peru, has been cultivated widely in China as a popular health care food. However, the chemical and effective studies of Maca were less in-depth, which restricted its application seriously. To ensure the quality of Maca, a feasible and accurate strategy was established. One hundred and sixty compounds including 30 reference standards were identified in 6 fractions of methanol extract of Maca by UHPLC-ESI-Orbitrap MS. Among them, 15 representative active compounds were simultaneously determined in 17 samples by UHPLC-ESI-QqQ MS. The results suggested that Maca from Yunnan province was the potential substitute for the one from Peru. Meanwhile, the neuroprotective effects of Maca were investigated. Three fractions and two pure compounds showed strong activities in the 1-methyl-4-phenyl-1, 2, 3, 6-tetrahydropyridine (MPTP)-induced zebrafish model. Among them, 80% methanol elution fraction (Fr5) showed significant neuroprotective activity, followed by 100% part (Fr6). The inhibition of acetylcholinesterase (AChE) and butyrylcholinesterase (BuChE) was a possible mechanism of its neuroprotective effect. PMID:28304399

Chemical profiling analysis of Maca using UHPLC-ESI-Orbitrap MS coupled with UHPLC-ESI-QqQ MS and the neuroprotective study on its active ingredients.

PubMed

Zhou, Yanyan; Li, Peng; Brantner, Adelheid; Wang, Hongjie; Shu, Xinbin; Yang, Jian; Si, Nan; Han, Lingyu; Zhao, Haiyu; Bian, Baolin

2017-03-17

Lepidium meyenii (Maca), originated from Peru, has been cultivated widely in China as a popular health care food. However, the chemical and effective studies of Maca were less in-depth, which restricted its application seriously. To ensure the quality of Maca, a feasible and accurate strategy was established. One hundred and sixty compounds including 30 reference standards were identified in 6 fractions of methanol extract of Maca by UHPLC-ESI-Orbitrap MS. Among them, 15 representative active compounds were simultaneously determined in 17 samples by UHPLC-ESI-QqQ MS. The results suggested that Maca from Yunnan province was the potential substitute for the one from Peru. Meanwhile, the neuroprotective effects of Maca were investigated. Three fractions and two pure compounds showed strong activities in the 1-methyl-4-phenyl-1, 2, 3, 6-tetrahydropyridine (MPTP)-induced zebrafish model. Among them, 80% methanol elution fraction (Fr 5 ) showed significant neuroprotective activity, followed by 100% part (Fr 6 ). The inhibition of acetylcholinesterase (AChE) and butyrylcholinesterase (BuChE) was a possible mechanism of its neuroprotective effect.

Exploring in vitro neurobiological effects and high-pressure liquid chromatography-assisted quantitation of chlorogenic acid in 18 Turkish coffee brands.

PubMed

Erdem, Sinem Aslan; Senol, F Sezer; Budakoglu, Esin; Orhan, Ilkay Erdogan; Sener, Bilge

2016-01-01

The hydroalcoholic extracts of the Turkish traditional coffee samples from 18 commercial brands were tested for their neurobiological effects through enzyme inhibition based on enzyme-linked immunosorbance microtiter assays against acetylcholinesterase, butyrylcholinesterase, and tyrosinase, linked to Alzheimer's and Parkinson's diseases. The extracts were also subjected to several antioxidant test systems to define their antiradical, metal-chelation capacity, and reducing power. Total phenol and flavonoid contents in the extracts were delineated by spectrophotometric methods, while chlorogenic acid in the coffee samples was quantified by high-pressure liquid chromatography. The extracts displayed low to moderate inhibition (from 2.13 ± 0.01% to 36.12 ± 1.07% at 200 μg/mL) against the tested enzymes, whereas they had notable 2,2'-diphenyl-1-picrylhydrazyl radical scavenging activity up to 56.15 ± 2.03% at 200 μg/mL. The extracts exerted a remarkable ferric-reducing antioxidant power values, while chlorogenic acid was found to range between 0.288 ± 0.005% and 2.335 ± 0.010%. Copyright © 2015. Published by Elsevier B.V.

Novel tetrahydrocarbazole benzyl pyridine hybrids as potent and selective butryl cholinesterase inhibitors with neuroprotective and β-secretase inhibition activities.

PubMed

Ghobadian, Roshanak; Mahdavi, Mohammad; Nadri, Hamid; Moradi, Alireza; Edraki, Najmeh; Akbarzadeh, Tahmineh; Sharifzadeh, Mohammad; Bukhari, Syed Nasir Abbas; Amini, Mohsen

2018-05-23

Butyrylcholinesterase (BuChE) inhibitors have become interesting target for treatment of Alzheimer's disease (AD). A series of dual binding site BuChE inhibitors were designed and synthesized based on 2,3,4,9-tetrahydro-1H-carbazole attached benzyl pyridine moieties. In-vitro assay revealed that all of the designed compounds were selective and potent BuChE inhibitors. The most potent BuChE inhibitor was compound 6i (IC 50  = 0.088 ± 0.0009 μM) with the mixed-type inhibition. Docking study revealed that 6i is a dual binding site BuChE inhibitor. Also, Pharmacokinetic properties for 6i were accurate to Lipinski's rule. In addition, compound 6i demonstrated neuroprotective and β-secretase (BACE1) inhibition activities. This compound could also inhibit AChE-induced and self-induced Aβ peptide aggregation at concentration of 100 μM and 10 μM respectively. Generally, the results are presented as new potent selective BuChE inhibitors with a therapeutic potential for the treatment of AD. Copyright © 2018 Elsevier Masson SAS. All rights reserved.

Acute cholinergic syndrome in a patient with mild Alzheimer's type dementia who had applied a large number of rivastigmine transdermal patches on her body.

PubMed

Suzuki, Yoshiki; Kamijo, Yoshito; Yoshizawa, Tomohiro; Fujita, Yuji; Usui, Kiyotaka; Kishino, Tohru

2017-11-01

A 91-year-old woman was transferred to our Emergency Medical Center and Poison Center with somnolence, hypertension (186/61 mm Hg), and repeated vomiting. Three hours later, 10 transdermal patches, each containing 18 mg of rivastigmine (9.5 mg/24 h), were found on her lower back and both thighs, when miosis, facial and trunk sweating, enhanced bowel sound, hypertension, and sinus tachycardia were noted. She was diagnosed with acute cholinergic syndrome due to rivastigmine poisoning. Her hypertension and sinus tachycardia peaked 8 and 5 h after all the patches were removed, respectively. Her symptoms subsided spontaneously after 17 h. In the present case, our patient was presented with acute cholinergic syndrome due to carbamate intoxication after massive transdermal exposure to rivastigmine. Toxicological analysis revealed a remarkably high estimated serum rivastigmine concentration (150.6 ng/ml) and notably low serum butyrylcholinesterase activity (35 IU/l) on admission, with a markedly prolonged calculated elimination half-life of 6.5 h. Emergency physicians should consider acetylcholinesterase inhibitor exposure (e.g., rivastigmine) when patients are present with acute cholinergic syndrome.

HPLC-DAD fingerprinting analysis, antioxidant activities of Tithonia diversifolia (Hemsl.) A. Gray leaves and its inhibition of key enzymes linked to Alzheimer's disease.

PubMed

Ojo, Oluwafemi Adeleke; Ojo, Adebola Busola; Ajiboye, Basiru Olaitan; Olaiya, Oluranti; Okesola, Mary Abiola; Boligon, Aline Augusti; de Campos, Marli Matiko Anraku; Oyinloye, Babatunji Emmanuel; Kappo, Abidemi Paul

2018-01-01

Tithonia diversifolia (Hemsl.) A. Gray leaves have long been used to manage neurodegenerative diseases without scientific basis. This study characterized the phenolic constituents, evaluated the antioxidant properties of phenolic extracts from T. diversifolia leaves used as traditional medicine in Africa and its inhibition of key enzymes linked to Alzheimer's disease. The extract was rich in phenolic acids (gallic acid, chlorogenic acid, caffeic acid and p -coumaric acid) and flavonoids (apigenin) and had 1,1-diphenyl-2-picryl-hydrazil radical scavenging abilities (IC 50  = 41.05 μg. mL -1 ), 2,2-Azino-bis3-ethylbenthiazoline-6sulphonic acid radical scavenging ability (IC 50  = 33.51 μg. mL -1 ), iron chelation (IC 50  = 38.50 μg. mL -1 ), reducing power (Fe 3+ - Fe 2+ ) (7.34 AAEmg/100 g), inhibited acetylcholinesterase (IC 50  = 39.27 μg mL -1 ) and butyrylcholinesterase (IC 50  = 35.01 μg mL -1 ) activities. These results reveal the leaf as a rich source of phenolic compounds with antioxidant and cholinesterase inhibitory activity.

Structure-activity relationship investigation of tertiary amine derivatives of cinnamic acid as acetylcholinesterase and butyrylcholinesterase inhibitors: compared with that of phenylpropionic acid, sorbic acid and hexanoic acid.

PubMed

Gao, Xiaohui; Tang, Jingjing; Liu, Haoran; Liu, Linbo; Kang, Lu; Chen, Wen

2018-12-01

In the present investigation, 48 new tertiary amine derivatives of cinnamic acid, phenylpropionic acid, sorbic acid and hexanoic acid (4d-6g, 10d-12g, 16d-18g and 22d-24g) were designed, synthesized and evaluated for the effect on AChE and BChE in vitro. The results revealed that the alteration of aminoalkyl types and substituted positions markedly influences the effects in inhibiting AChE. Almost of all cinnamic acid derivatives had the most potent inhibitory activity than that of other acid derivatives with the same aminoalkyl side chain. Unsaturated bond and benzene ring in cinnamic acid scaffold seems important for the inhibitory activity against AChE. Among them, compound 6g revealed the most potent AChE inhibitory activity (IC 50 value: 3.64 µmol/L) and highest selectivity over BChE (ratio: 28.6). Enzyme kinetic study showed that it present a mixed-type inhibition against AChE. The molecular docking study suggested that it can bind with the catalytic site and peripheral site of AChE.

Microwave-assisted synthesis of novel purine nucleosides as selective cholinesterase inhibitors.

PubMed

Schwarz, S; Csuk, R; Rauter, A P

2014-04-21

Alzheimer's disease (AD), the most common form of senile dementia, is characterized by high butyrylcholinesterase (BChE) levels in the brain in later AD stages, for which no treatment is available. Pursuing our studies on selective BChE inhibitors, that may contribute to understand the role of this enzyme in disease progression, we present now microwave-assisted synthesis and anticholinesterase activity of a new nucleoside series embodying 6-chloropurine or 2-acetamido-6-chloropurine linked to D-glucosyl, D-galactosyl and D-mannosyl residues. It was designed to assess the contribution of sugar stereochemistry, purine structure and linkage to the sugar for cholinesterase inhibition efficiency and selectivity. Compounds were subjected to Ellman's assay and their inhibition constants determined. The α-anomers were the most active compounds, while selectivity for BChE or acetylcholinesterase (AChE) inhibition could be tuned by the purine base, by the glycosyl moiety and by N(7)-ligation. Some of the nucleosides were far more potent than the drug galantamine, and the most promising competitive and selective BChE inhibitor, the N(7)-linked 2-acetamido-α-D-mannosylpurine, showed a Ki of 50 nM and a selectivity factor of 340 fold for BChE over AChE.

Novel tacrine-1,2,3-triazole hybrids: In vitro, in vivo biological evaluation and docking study of cholinesterase inhibitors.

PubMed

Najafi, Zahra; Mahdavi, Mohammad; Saeedi, Mina; Karimpour-Razkenari, Elahe; Asatouri, Raymond; Vafadarnejad, Fahimeh; Moghadam, Farshad Homayouni; Khanavi, Mahnaz; Sharifzadeh, Mohammad; Akbarzadeh, Tahmineh

2017-01-05

A new series of tacrine-1,2,3-triazole hybrids were designed, synthesized, and evaluated as potent dual cholinesterase inhibitors. Most of synthesized compounds showed good in vitro inhibitory activities toward both acetylcholinesterase (AChE) and butyrylcholinesterase (BChE). Among them, 7-chloro-N-((1-(4-methoxybenzyl)-1H-1,2,3-triazol-4-yl)methyl)-1,2,3,4-tetrahydroacridin-9-amine (5l) was found to be the most potent anti-AChE derivative (IC 50  = 0.521 μM) and N-((1-(4-methoxybenzyl)-1H-1,2,3-triazol-4-yl)methyl)-1,2,3,4-tetrahydroacridin-9-amine (5j) demonstrated the best anti-BChE activity (IC 50  = 0.055 μM). In vivo studies of compound 5l in Morris water maze task confirmed memory improvement in scopolamine-induced impairment. Also, molecular modeling and kinetic studies showed that compounds 5l and 5j bound simultaneously to the peripheral anionic site (PAS) and catalytic sites (CS) of the AChE and BChE. Copyright © 2016 Elsevier Masson SAS. All rights reserved.

Synthesis of novel 5-(aroylhydrazinocarbonyl)escitalopram as cholinesterase inhibitors.

PubMed

Nisa, Mehr-Un; Munawar, Munawar A; Iqbal, Amber; Ahmed, Asrar; Ashraf, Muhammad; Gardener, Qurra-Tul-Ann A; Khan, Misbahul A

2017-09-29

A novel series of 5-(aroylhydrazinocarbonyl)escitalopram (58-84) have been designed, synthesized and tested for their inhibitory potential against cholinesterases. 3-Chlorobenzoyl- (71) was found to be the most potent compound of this series having IC 50 1.80 ± 0.11 μM for acetylcholinesterase (AChE) inhibition. For the butyrylcholinesterase (BChE) inhibition, 2-bromobenzoyl- (76) was the most active compound of the series with IC 50 2.11 ± 0.31 μM. Structure-activity relationship illustrated that mild electron donating groups enhanced enzyme inhibition while electron withdrawing groups reduced the inhibition except o-NO 2 . However, size and position of the substituents affected enzyme inhibitions. . In docking study of AChE, the ligands 71, 72 and 76 showed the scores of 5874, 5756 and 5666 and ACE of -64.92,-203.25 and -140.29 kcal/mol, respectively. In case of BChE, ligands 71, 76 and 81 depicted high scores 6016, 6150 and 5994 with ACE values -170.91, -256.84 and -235.97 kcal/mol, respectively. Copyright © 2017 Elsevier Masson SAS. All rights reserved.

Characterization of potent anticholinesterase plant oil based microemulsion.

PubMed

Chaiyana, Wantida; Saeio, Kiattisak; Hennink, Wim E; Okonogi, Siriporn

2010-11-30

In the present study, essential oils of three edible Thai plants, Cymbopogon citratus (Gramineae), Citrus hystrix (Rutaceae) and Zingiber cassumunar (Zingiberaceae) were comparatively tested for acetylcholinesterase (AChE) and butyrylcholinesterase (BChE) inhibitory activities using Ellman's colorimetric method. C. citratus oil exhibited the highest activity with IC(50) values of 0.34±0.07μl/ml and 2.14±0.18μl/ml against BChE and AChE activity, respectively. It was further investigated whether microemulsions of this oil could be obtained. The effects of type of surfactant and co-surfactant as well as pH and ionic strength on the phase behavior of the oil/water system were investigated. Brij 97, Triton X-114, Tween 20 and Tween 85 were employed as surfactant whereas ethanol and hexanol were used as cosurfactants. The size analysis, electrical conductivity measurements and cholinesterase inhibition assays were done in selected microemulsion. The results revealed that the type and concentration of surfactant and co-surfactant exhibited a distinct influence on the C. citratus oil microemulsions. Moreover, the inhibitory activities of the microemulsion formulation were remarkable. Copyright © 2010 Elsevier B.V. All rights reserved.

Accumulation of phenolic compounds in in vitro cultures and wild plants of Lavandula viridis L'Hér and their antioxidant and anti-cholinesterase potential.

PubMed

Costa, Patrícia; Gonçalves, Sandra; Valentão, Patrícia; Andrade, Paula B; Romano, Anabela

2013-07-01

In this study, we evaluated the phenolic profile, antioxidant and anti-cholinesterase potential of different extracts from wild plants and in vitro cultures of Lavandula viridis L'Hér. The HPLC-DAD analysis allowed the identification and quantification of 3-O-caffeoylquinic, 4-O-caffeoylquinic, 5-O-caffeoylquinic and rosmarinic acids, and luteolin and pinocembrin. Water/ethanol extract from in vitro cultures contained the highest amount of the identified phenolic compounds (51652.92 mg/kg). To investigate the antioxidant activity we used Trolox equivalent antioxidant capacity, oxygen radical absorbance capacity, Fe(2+) chelation activity and the inhibition of Fe(2+)-induced lipid peroxidation in mouse brain homogenates (in vitro). Overall, all the extracts from both wild plants and in vitro cultures exhibited ability to scavenge free radicals, to chelate Fe(2+) and to protect against lipid peroxidation. In addition, the extracts from L. viridis were active in inhibiting both acetylcholinesterase and butyrylcholinesterase (Ellman's method). Our findings suggest that L. viridis in vitro cultures represent a promising alternative for the production of active metabolites with antioxidant and anti-cholinesterase activity. Copyright © 2013 Elsevier Ltd. All rights reserved.

Phenolic, flavonoid contents, anticholinesterase and antioxidant evaluation of Iris germanica var; florentina.

PubMed

Ullah, Farhat; Ayaz, Muhammad; Sadiq, Abdul; Hussain, Abid; Ahmad, Sajjad; Imran, Muhammad; Zeb, Anwar

2016-06-01

This study was designed to investigate antioxidant and anticholinesterase potential of Iris germanica var; florentina. Acetylcholinesterase (AChE) and butyrylcholinesterase (BChE) inhibitory potential of plant samples were investigated by Ellman's assay. Antioxidant activity was performed using DPPH, H2O2 and ABTS free radical scavenging assays. Total phenolics and flavonoids contents were expressed in mg GAE/g dry weight and mg RTE/g, respectively. In AChE inhibition assay, Ig.Fl, Ig.Sp and Ig.Cf fractions exhibited highest activity with IC50 values of < 0.1, 5.64 and 19 μg/mL, respectively. In BChE inhibitory assay, Ig.Fl, Ig.Sp, Ig.Cf and Ig.Cr were most active with IC50 of < 0.1, < 0.1, 31 and 78 μg/mL, respectively. In DPPH assay, Ig.Fl and Ig.Cf exhibited highest inhibition of free radicals, 80.52% (IC50 = 9 μg/mL) and 78.30% (IC50 = 8 μg/mL), respectively. In ABTS assay Ig.Cr, Ig.Cf, Ig.Fl and Ig.Sp exhibited IC50 values of < 0.1, 2, 2 and 3 μg/mL, respectively.

Isolation of cholinesterase and β-secretase 1 inhibiting compounds from Lycopodiella cernua.

PubMed

Nguyen, Van Thu; To, Dao Cuong; Tran, Manh Hung; Oh, Sang Ho; Kim, Jeong Ah; Ali, Md Yousof; Woo, Mi-Hee; Choi, Jae Sue; Min, Byung Sun

2015-07-01

Three new serratene-type triterpenoids (1-3) and a new hydroxy unsaturated fatty acid (13) together with nine known compounds (4-12) were isolated from Lycopodiella cernua. The chemical structures were established using NMR, MS, and Mosher's method. Compound 13 showed the most potent inhibitory activity against acetylcholinesterase (AChE) with an IC50 value of 0.22μM. For butyrylcholinesterase (BChE) inhibitory activity, 5 showed the most potent activity with an IC50 value of 0.42μM. Compound 2 showed the most potent activity with an IC50 of 0.23μM for BACE-1 inhibitory activity. The kinetic activities were investigated to determine the type of enzyme inhibition involved. The types of AChE inhibition shown by compounds 4, 5, and 13 were mixed; BChE inhibition by 5 was competitive, while 2 and 6 showed mixed-types. In addition, molecular docking studies were performed to investigate the interaction of these compounds with the pocket sites of AChE. The docking results revealed that the tested inhibitors 3, 4, and 13 were stably present in several pocket domains of the AChE residue. Copyright © 2015 Elsevier Ltd. All rights reserved.

Phytochemical profile of a blend of black chokeberry and lemon juice with cholinesterase inhibitory effect and antioxidant potential.

PubMed

Gironés-Vilaplana, Amadeo; Valentão, Patrícia; Andrade, Paula B; Ferreres, Federico; Moreno, Diego A; García-Viguera, Cristina

2012-10-15

In this study, black chokeberry concentrate was added (5% w/v) to lemon juice, since previous reports suggested potential health benefits of this blend. The phytochemical composition, antioxidant capacity (scavenging of DPPH, superoxide and hydroxyl radicals, and hypochlorous acid), and inhibitory activity against cholinesterase of the new blend were determined and compared with those of lemon juice and chokeberry in citric acid (5%). The chokeberry concentrate, rich in cyanidin-glycosides, quercetin derivatives, and 3-O-caffeoylquinic acid, and lemon juice, possessing flavones, flavanones, quercetin derivates, and hydroxycinnamic acids, were characterised. The new drink showed a higher antioxidant effect than the chokeberry or lemon controls for all the tested methods, except for hypochlorous acid, in which lemon juice displayed higher activity. Both the lemon juice and chokeberry controls inhibited acetylcholinesterase and butyrylcholinesterase, and this effect was increased in the new mixtures. The results of the different radical scavenging assays indicate that the lemon-black chokeberry (5% w/v) mixture was more antioxidative than the respective controls separately. Moreover, their inhibition of cholinesterase is of interest regarding neurodegenerative disorders such as Alzheimer's disease, Parkinson's disease, or senile dementia. Copyright © 2012 Elsevier Ltd. All rights reserved.

Coumarin derivatives bearing benzoheterocycle moiety: synthesis, cholinesterase inhibitory, and docking simulation study

PubMed Central

Hirbod, Kimia; Jalili-baleh, Leili; Nadri, Hamid; ebrahimi, Seyed esmaeil Sadat; Moradi, Alireza; Pakseresht, Bahar; Foroumadi, Alireza; Shafiee, Abbas; Khoobi, Mehdi

2017-01-01

Objective(s): To investigate the efficiency of a novel series of coumarin derivatives bearing benzoheterocycle moiety as novel cholinesterase inhibitors. Materials and Methods: Different 7-hydroxycoumarin derivatives were synthesized via Pechmann or Knoevenagel condensation and conjugated to different benzoheterocycle (8-hydroxyquinoline, 2-mercaptobenzoxazole or 2-mercaptobenzimidazole) using dibromoalkanes 3a-m: Final compounds were evaluated against acetylcholinesterase (AChE) and butyrylcholinesterase (BuChE) by Ellman’s method. Kinetic study of AChE inhibition and ligand-protein docking simulation were also carried out for the most potent compound 3b. Results: Some of the compounds revealed potent and selective activity against AChE. Compound 3b containing the quinoline group showed the best activity with an IC50 value of 8.80 μM against AChE. Kinetic study of AChE inhibition revealed the mixed-type inhibition of the enzyme by compound 3b. Ligand-protein docking simulation also showed that the flexibility of the hydrophobic five carbons linker allows the quinoline ring to form π-π interaction with Trp279 in the PAS. Conclusion: We suggest these synthesized compounds could become potential leads for AChE inhibition and prevention of AD symptoms. PMID:28868119

Folding anomalies of neuroligin3 caused by a mutation in the alpha/beta-hydrolase fold domain.

PubMed

De Jaco, Antonella; Dubi, Noga; Comoletti, Davide; Taylor, Palmer

2010-09-06

Proteins of the alpha/beta-hydrolase fold family share a common structural fold, but perform a diverse set of functions. We have been studying natural mutations occurring in association with congenital disorders in the alpha/beta-hydrolase fold domain of neuroligin (NLGN), butyrylcholinesterase (BChE), acetylcholinesterase (AChE). Starting from the autism-related R451C mutation in the alpha/beta-hydrolase fold domain of NLGN3, we had previously shown that the Arg to Cys substitution is responsible for endoplasmic reticulum (ER) retention of the mutant protein and that a similar trafficking defect is observed when the mutation is inserted at the homologous positions in AChE and BChE. Herein we show further characterization of the R451C mutation in NLGN3 when expressed in HEK-293, and by protease digestion sensitivity, we reveal that the phenotype results from protein misfolding. However, the presence of an extra Cys does not interfere with the formation of disulfide bonds as shown by reaction with PEG-maleimide and estimation of the molecular mass changes. These findings highlight the role of proper protein folding in protein processing and localization. Copyright (c) 2010 Elsevier Ireland Ltd. All rights reserved.

FOLDING ANOMALIES OF NEUROLIGIN3 CAUSED BY A MUTATION IN THE α/β-HYDROLASE FOLD DOMAIN

PubMed Central

De Jaco, Antonella; Dubi, Noga; Comoletti, Davide; Taylor, Palmer

2017-01-01

Proteins of the α/β-hydrolase fold family share a common structural fold, but perform a diverse set of functions. We have been studying natural mutations occurring in association with congenital disorders in the α/β-hydrolase fold domain of neuroligin (NLGN), butyrylcholinesterase (BChE), acetylcholinesterase (AChE). Starting from the autism-related R451C mutation in the α/β-hydrolase fold domain of NLGN3, we had previously shown that the Arg to Cys substitution is responsible for endoplasmic reticulum (ER) retention of the mutant protein and that a similar trafficking defect is observed when the mutation is inserted at the homologous positions in AChE and BChE. Herein we show further characterization of the R451C mutation in NLGN3 when expressed in HEK-293, and by protease digestion sensitivity, we reveal that the phenotype results from protein misfolding. However, the presence of an extra Cys doesn’t interfere with the formation of disulfide bonds as shown by reaction with PEG-maleimide and estimation of the molecular mass changes. These findings highlight the role of proper protein folding in protein processing and localization. PMID:20227402

Evaluation of antioxidant potential, enzyme inhibition activity and phenolic profile of Lathyrus cicera and Lathyrus digitatus: Potential sources of bioactive compounds for the food industry.

PubMed

Llorent-Martínez, E J; Ortega-Barrales, P; Zengin, G; Mocan, A; Simirgiotis, M J; Ceylan, R; Uysal, S; Aktumsek, A

2017-09-01

The genus Lathyrus has great importance in terms of food and agricultural areas. In this study, the in vitro antioxidant activity (phosphomolybdenum, DPPH, ABTS, FRAP, CUPRAC and metal chelating) and enzyme inhibitory activity evaluation (acetylcholinesterase, butyrylcholinesterase, α-amylase and α-glucosidase) of L. cicera and L. digitatus were investigated, as well as their phytochemical profiles. The screening of the main phytochemical compounds in aerial parts of L. cicera and L. digitatus was carried out by high-performance liquid chromatography with electrospray ionization mass spectrometric detection (HPLC-ESI-MS n ), observing that flavonoids represent the highest percentage of identified compounds, with abundance of tri- and tetra-glycosilated flavonoids, including acylated ones, especially in L. cicera. Generally, L. digitatus exhibited stronger antioxidant and enzyme inhibitory activities in correlation with its higher level of phenolics. The high number of phenolic compounds and the results of the antioxidant and enzyme assays suggest that these plants may be further used as sources of bioactive compounds, and for the preparation of new nutraceuticals. Copyright © 2017 Elsevier Ltd. All rights reserved.

Relationship between LINE-1 methylation pattern and pesticide exposure in urban sprayers.

PubMed

Benitez-Trinidad, Alma Betsaida; Medina-Díaz, Irma Martha; Bernal-Hernández, Yael Yvette; Barrón-Vivanco, Briscia Socorro; González-Arias, Cyndia Azucena; Herrera-Moreno, José Francisco; Alvarado-Cruz, Isabel; Quintanilla-Vega, Betzabet; Rojas-García, Aurora Elizabeth

2018-03-01

Recently a relationship has been reported between pesticide exposure and changes in global DNA methylation patterns. Urban sprayers are a particularly vulnerable population because of the high risk of pesticide exposure that their work implies. Therefore, the aim of this study was to estimate the changes in the Long Interspersed Nucleotide Element (LINE-1) in urban sprayers and its relationship with pesticide exposure. The study population consisted of 190 individuals stratified into three study groups: no occupational pesticide exposure; moderate exposure, and high exposure. Pesticide exposure and other external factors such as diet, lifestyle, and others were evaluated through a validated questionnaire, and the butyrylcholinesterase enzyme activity was evaluated spectrophotometrically and used as exposure biomarker. DNA methylation was evaluated by pyrosequencing on bisulfite-treated DNA. The results showed a significant decrease of %5mC in both the moderate- and high-exposure groups with respect to the non-exposed group (p < 0.05). In addition, alcohol intake was associated with a higher percentage of LINE- 1 methylation. In conclusion, our results suggest that occupational pesticide exposure and external factors appears to modify the DNA methylation pattern measured through LINE-1. Copyright © 2018 Elsevier Ltd. All rights reserved.

Dysregulated Homeostasis of Acetylcholine Levels in Immune Cells of RR-Multiple Sclerosis Patients.

PubMed

Di Bari, Maria; Reale, Marcella; Di Nicola, Marta; Orlando, Viviana; Galizia, Sabrina; Porfilio, Italo; Costantini, Erica; D'Angelo, Chiara; Ruggieri, Serena; Biagioni, Stefano; Gasperini, Claudio; Tata, Ada Maria

2016-11-30

Multiple sclerosis (MS) is characterized by pro-inflammatory cytokine production. Acetylcholine (ACh) contributes to the modulation of central and peripheral inflammation. We studied the homeostasis of the cholinergic system in relation to cytokine levels in immune cells and sera of relapsing remitting-MS (RR-MS) patients. We demonstrated that lower ACh levels in serum of RR-MS patients were inversely correlated with the increased activity of the hydrolyzing enzymes acetylcholinesterase (AChE) and butyrylcholinesterase (BuChE). Interestingly, the expression of the ACh biosynthetic enzyme and the protein carriers involved in non-vesicular ACh release were found overexpressed in peripheral blood mononuclear cells of MS patients. The inflammatory state of the MS patients was confirmed by increased levels of TNFα, IL-12/IL-23p40, IL-18. The lower circulating ACh levels in sera of MS patients are dependent on the higher activity of cholinergic hydrolyzing enzymes. The smaller ratio of ACh to TNFα, IL-12/IL-23p40 and IL-18 in MS patients, with respect to healthy donors (HD), is indicative of an inflammatory environment probably related to the alteration of cholinergic system homeostasis.

Dysregulated Homeostasis of Acetylcholine Levels in Immune Cells of RR-Multiple Sclerosis Patients

PubMed Central

Di Bari, Maria; Reale, Marcella; Di Nicola, Marta; Orlando, Viviana; Galizia, Sabrina; Porfilio, Italo; Costantini, Erica; D’Angelo, Chiara; Ruggieri, Serena; Biagioni, Stefano; Gasperini, Claudio; Tata, Ada Maria

2016-01-01

Multiple sclerosis (MS) is characterized by pro-inflammatory cytokine production. Acetylcholine (ACh) contributes to the modulation of central and peripheral inflammation. We studied the homeostasis of the cholinergic system in relation to cytokine levels in immune cells and sera of relapsing remitting-MS (RR-MS) patients. We demonstrated that lower ACh levels in serum of RR-MS patients were inversely correlated with the increased activity of the hydrolyzing enzymes acetylcholinesterase (AChE) and butyrylcholinesterase (BuChE). Interestingly, the expression of the ACh biosynthetic enzyme and the protein carriers involved in non-vesicular ACh release were found overexpressed in peripheral blood mononuclear cells of MS patients. The inflammatory state of the MS patients was confirmed by increased levels of TNFα, IL-12/IL-23p40, IL-18. The lower circulating ACh levels in sera of MS patients are dependent on the higher activity of cholinergic hydrolyzing enzymes. The smaller ratio of ACh to TNFα, IL-12/IL-23p40 and IL-18 in MS patients, with respect to healthy donors (HD), is indicative of an inflammatory environment probably related to the alteration of cholinergic system homeostasis. PMID:27916909

Cholinesterases as markers of the inflammatory process associated oxidative stress in cattle infected by Babesia bigemina.

PubMed

Doyle, Rovaina L; Da Silva, Aleksandro S; Oliveira, Camila B; França, Raqueli T; Carvalho, Fabiano B; Abdalla, Fátima H; Costa, Pauline; Klafke, Guilherme M; Martins, João R; Tonin, Alexandre A; Castro, Verônica S P; Santos, Franklin G B; Lopes, Sonia T A; Andrade, Cinthia M

2016-06-01

The objective of this study was to assess the influence of an asymptomatic experimental infection by Babesia bigemina on cholinesterase's as markers of the inflammatory process and biomarkers of oxidative imbalance. For this purpose, eight naive animals were used, as follows: four as controls or uninfected; and four infected with an attenuated strain of B. bigemina. Blood samples were collected on days 0, 7 and 11 post-inoculation (PI). Parasitemia was determined by blood smear evaluation, showing that the infection by B. bigemina resulted in mean 0.725 and 0.025% on day 7 and 11 PI, respectively, as well as mild anemia. The activities of acetylcholinesterase, butyrylcholinesterase and catalase were lower, while levels of thiobarbituric acid reactive substances and superoxide dismutase activity were higher in infected animals, when compared with the control group. This attenuated strain of B. bigemina induced an oxidative stress condition, as well as it reduces the cholinesterasés activity in infected and asymptomatic cattle. Therefore, this decrease of cholinesterase in infection by B. bigemina purpose is to inhibit inflammation, for thereby increasing acetylcholine levels, potent anti-inflammatory molecules. Copyright © 2016. Published by Elsevier Ltd.

Design, synthesis and evaluation of novel 7-aminoalkyl-substituted flavonoid derivatives with improved cholinesterase inhibitory activities.

PubMed

Luo, Wen; Chen, Ying; Wang, Ting; Hong, Chen; Chang, Li-Ping; Chang, Cong-Cong; Yang, Ya-Cheng; Xie, Song-Qiang; Wang, Chao-Jie

2016-02-15

A novel series of 7-aminoalkyl-substituted flavonoid derivatives 5a-5r were designed, synthesized and evaluated as potential cholinesterase inhibitors. The results showed that most of the synthesized compounds exhibited potent acetylcholinesterase (AChE) and butyrylcholinesterase (BChE) inhibitory activities at the micromolar range. Compound 2-(naphthalen-1-yl)-7-(8-(pyrrolidin-1-yl)octyloxy)-4H-chromen-4-one (5q) showed the best inhibitory activity (IC50, 0.64μM for AChE and 0.42μM for BChE) which were better than our previously reported compounds and the commercially available cholinergic agent Rivastigmine. The results from a Lineweaver-Burk plot indicated a mixed-type inhibition for compound 5q with AChE and BChE. Furthermore, molecular modeling study showed that 5q targeted both the catalytic active site (CAS) and the peripheral anionic site (PAS) of AChE. Besides, these compounds (5a-5r) did not affect PC12 and HepG2 cell viability at the concentration of 10μM. Consequently, these flavonoid derivatives should be further investigated as multipotent agents for the treatment of Alzheimer's disease. Copyright © 2015 Elsevier Ltd. All rights reserved.

Chemical and molecular aspects on interactions of galanthamine and its derivatives with cholinesterases.

PubMed

Gulcan, Hayrettin O; Orhan, Ilkay E; Sener, Bilge

2015-01-01

Dual action of galanthamine as potent cholinesterase inhibitor and nicotinic modulator has attracted a great attention to be used in the treatment of AD. Consequently, galanthamine, a natural alkaloid isolated from a Galanthus species (snowdrop, Amaryllidaceae), has become an attractive model compound for synthesis of its novel derivatives to discover new drug candidates. Numerous studies have been done to elucidate interactions between galanthamine and its different derivatives and the enzymes; acetylcholinesterase (AChE) and butyrylcholinesterase (BChE) using in vitro and in silico experimental models. The in vitro studies revealed that galanthamine inhibits AChE in strong, competitive, long-acting, and reversible manner as well as BChE, although its selectivity towards AChE is much higher than BChE. The in silico studies carried out by employing molecular docking experiments as well as molecular dynamics simulations pointed out to existence of strong interactions of galanthamine with the active gorge of AChE, mostly of Torpedo californica (the Pasific electric ray) origin. In this review, we evaluate the mainstays of cholinesterase inhibitory action of galanthamine and its various derivatives from the point of view of chemical and molecular aspects.

The significance of low substrate concentration measurements for mechanistic interpretation in cholinesterases.

PubMed

Stojan, Jure

2013-03-25

Cholinesterases do not follow the Michaelis-Menten kinetics. In the past, many reaction schemes were suggested to explain their complex interactions during the substrate turnover. Covalent catalysis was recognized very early and therefore, double intermediate traditional reaction scheme for the hydrolysis of good substrates at low concentrations was postulated. However, at intermediate and high substrate concentrations homotropic pseudocooperative effects take place in all cholinesterases, due to the nature of their buried active center. In this study, the significance and usefulness of experimental data obtained at low substrate concentrations, where only one substrate molecule accesses the active site at a time, are to be specified for the overall mechanistic evaluations. Indeed, different interpretations are expected when data are processed with equations derived from different reaction schemes. Consequently, the scheme with two substrate binding sites which comprises the structurally evidenced fully occupied active site as ultimate cause for substantially decreased cholinesterase activity at extremely high substrate concentrations is considered here. A special emphasis is put on butyrylcholinesterase, the enzyme with the largest active site among cholinesterases, where the pseudocooperative effects appear at much higher concentrations than in acetylcholinesterases. Copyright © 2012 Elsevier Ireland Ltd. All rights reserved.

Evaluation of Antioxidant, Anti-cholinesterase, and Anti-inflammatory Effects of Culinary Mushroom Pleurotus pulmonarius.

PubMed

Nguyen, Trung Kien; Im, Kyung Hoan; Choi, Jaehyuk; Shin, Pyung Gyun; Lee, Tae Soo

2016-12-01

Culinary mushroom Pleurotus pulmonarius has been popular in Asian countries. In this study, the anti-oxidant, cholinesterase, and inflammation inhibitory activities of methanol extract (ME) of fruiting bodies of P. pulmonarius were evaluted. The 1,1-diphenyl-2-picryl-hydrazy free radical scavenging activity of ME at 2.0 mg/mL was comparable to that of butylated hydroxytoluene, the standard reference. The ME exhibited significantly higher hydroxyl radical scavenging activity than butylated hydroxytoluene. ME showed slightly lower but moderate inhibitory activity against acetylcholinesterase (AChE) and butyrylcholinesterase than galantamine, a standard AChE inhibitor. It also exhibited protective effect against cytotoxicity to PC-12 cells induced by glutamate (10~100 µg/mL), inhibitory effect on nitric oxide (NO) production and inducible nitric oxide synthase protein expression in lipopolysaccharide-stimulated RAW 264.7 macrophages, and carrageenan-induced paw edema in a rat model. High-performance liquid chromatography analysis revealed the ME of P. pulmonarius contained at least 10 phenolic compounds and some of them were identified by the comparison with known standard phenolics. Taken together, our results demonstrate that fruiting bodies of P. pulmonarius possess antioxidant, anti-cholinesterase, and inflammation inhibitory activities.

Evaluation of Antioxidant, Anti-cholinesterase, and Anti-inflammatory Effects of Culinary Mushroom Pleurotus pulmonarius

PubMed Central

Nguyen, Trung Kien; Im, Kyung Hoan; Choi, Jaehyuk; Shin, Pyung Gyun

2016-01-01

Culinary mushroom Pleurotus pulmonarius has been popular in Asian countries. In this study, the anti-oxidant, cholinesterase, and inflammation inhibitory activities of methanol extract (ME) of fruiting bodies of P. pulmonarius were evaluted. The 1,1-diphenyl-2-picryl-hydrazy free radical scavenging activity of ME at 2.0 mg/mL was comparable to that of butylated hydroxytoluene, the standard reference. The ME exhibited significantly higher hydroxyl radical scavenging activity than butylated hydroxytoluene. ME showed slightly lower but moderate inhibitory activity against acetylcholinesterase (AChE) and butyrylcholinesterase than galantamine, a standard AChE inhibitor. It also exhibited protective effect against cytotoxicity to PC-12 cells induced by glutamate (10~100 µg/mL), inhibitory effect on nitric oxide (NO) production and inducible nitric oxide synthase protein expression in lipopolysaccharide-stimulated RAW 264.7 macrophages, and carrageenan-induced paw edema in a rat model. High-performance liquid chromatography analysis revealed the ME of P. pulmonarius contained at least 10 phenolic compounds and some of them were identified by the comparison with known standard phenolics. Taken together, our results demonstrate that fruiting bodies of P. pulmonarius possess antioxidant, anti-cholinesterase, and inflammation inhibitory activities. PMID:28154487

Synthesis and biological evaluation of ranitidine analogs as multiple-target-directed cognitive enhancers for the treatment of Alzheimer's disease.

PubMed

Gao, Jie; Midde, Narasimha; Zhu, Jun; Terry, Alvin V; McInnes, Campbell; Chapman, James M

2016-11-15

Using molecular modeling and rationally designed structural modifications, the multi-target structure-activity relationship for a series of ranitidine analogs has been investigated. Incorporation of a variety of isosteric groups indicated that appropriate aromatic moieties provide optimal interactions with the hydrophobic and π-π interactions with the peripheral anionic site of the AChE active site. The SAR of a series of cyclic imides demonstrated that AChE inhibition is increased by additional aromatic rings, where 1,8-naphthalimide derivatives were the most potent analogs and other key determinants were revealed. In addition to improving AChE activity and chemical stability, structural modifications allowed determination of binding affinities and selectivities for M1-M4 receptors and butyrylcholinesterase (BuChE). These results as a whole indicate that the 4-nitropyridazine moiety of the JWS-USC-75IX parent ranitidine compound (JWS) can be replaced with other chemotypes while retaining effective AChE inhibition. These studies allowed investigation into multitargeted binding to key receptors and warrant further investigation into 1,8-naphthalimide ranitidine derivatives for the treatment of Alzheimer's disease. Copyright © 2016 Elsevier Ltd. All rights reserved.

Inhibition of spicule elongation in sea urchin embryos by the acetylcholinesterase inhibitor eserine.

PubMed

Ohta, Kazumasa; Takahashi, Chifumi; Tosuji, Hiroaki

2009-08-01

The activity of acetylcholinesterase (AchE) increases rapidly after the gastrula stage of sea urchin development. In this report, changes in activity and in the molecular differentiation of AchE were investigated. AchE activity increased slightly during gastrulation and rose sharply thereafter, and was dependent on new RNA synthesis. No activity of butyrylcholinesterase was found. Morphogenesis in sea urchin embryos was inhibited by the AchE inhibitor eserine, which specifically inhibited arm rod formation but not body rod formation. Spicule formation and enzyme activity in cultured micromeres were inhibited by eserine in a dose-dependent manner. During gastrulation, two molecular forms of AchE were detected with polyacrylamide gel electrophoresis. The appearance of an additional band on the gel was consistent with the occurrence of a remarkable increase in the enzyme activity. This additional band appeared as a larger molecular form in Anthocidaris crassispina, Hemicentrotus pulcherrimus, Stomopneustes variolaris, and Strongylocentrotus nudus, and as a smaller form in Clypeaster japonicus and Temnopleurus hardwicki. These results suggest that the change in the molecular form of AchE induced a change in enzymatic activity that in turn may play a role in spicule elongation in sea urchin embryos.

Chemical composition and bioactivity of Citrus medica L. cv. Diamante essential oil obtained by hydrodistillation, cold-pressing and supercritical carbon dioxide extraction.

PubMed

Menichini, Federica; Tundis, Rosa; Bonesi, Marco; de Cindio, Bruno; Loizzo, Monica R; Conforti, Filomena; Statti, Giancarlo A; Menabeni, Roberta; Bettini, Ruggero; Menichini, Francesco

2011-04-01

The chemical composition of the essential oil of Citrus medica L. cv. Diamante peel obtained by hydrodistillation, cold-pressing and supercritical carbon dioxide extraction techniques was determined by GC/MS analysis. Forty-six components were fully characterised. Limonene and γ-terpinene were the major components of the oils obtained by hydrodistillation (HD) and cold-pressing (CP), while citropten was the major constituent in the oil obtained by supercritical carbon dioxide extraction (SFE). Acetylcholinesterase (AChE) and butyrylcholinesterase (BChE) inhibitory activities were evaluated. The essential oil obtained by hydrodistillation exerted the highest inhibitory activity against BChE (IC₅₀ value of 154.6 µg mL⁻¹) and AChE (IC₅₀ value of 171.3 µg mL⁻¹. Interestingly, the oil obtained by cold-pressing exhibited a selective inhibitory activity against AChE. The essential oils have also been evaluated for the inhibition of NO production in LPS induced RAW 264.7 macrophages. The oil obtained by hydrodistillation exerted a significant inhibition of NO production with an IC₅₀ value of 17 µg mL⁻¹ (IC₅₀ of positive control 53 µg mL⁻¹).

Evaluation of biochemical and redox parameters in rats fed with corn grown in soil amended with urban sewage sludge.

PubMed

Grotto, Denise; Carneiro, Maria Fernanda Hornos; Sauer, Elisa; Garcia, Solange Cristina; de Melo, Wanderley José; Barbosa, Fernando

2013-09-01

The increased production of urban sewage sludge requires alternative methods for final disposal. A very promising choice is the use of sewage sludge as a fertilizer in agriculture, since it is rich in organic matter, macro and micronutrients. However, urban sewage sludge may contain toxic substances that may cause deleterious effects on the biota, water and soil, and consequently on humans. There is a lack of studies evaluating how safe the consumption of food cultivated in soils containing urban sewage sludge is. Thus, the aim of this paper was to evaluate biochemical and redox parameters in rats fed with corn produced in a soil treated with urban sewage sludge for a long term. For these experiments, maize plants were grown in soil amended with sewage sludge (rates of 5, 10 and 20 t/ha) or not (control). Four different diets were prepared with the corn grains produced in the field experiment, and rats were fed with these diets for 1, 2, 4, 8 and 12 weeks. Biochemical parameters (glucose, total cholesterol and fractions, triglycerides, aspartate aminotransferase and alanine aminotransferase) as well the redox state biomarkers such as reduced glutathione (GSH), malondialdehyde (MDA), catalase, glutathione peroxidase and butyrylcholinesterase (BuChE) were assessed. Our results show no differences in the biomarkers over 1 or 2 weeks. However, at 4 weeks BuChE activity was inhibited in rats fed with corn grown in soil amended with sewage sludge (5, 10 and 20 t/ha), while MDA levels increased. Furthermore, prolonged exposure to corn cultivated in the highest amount per hectare of sewage sludge (8 and 12 weeks) was associated with an increase in MDA levels and a decrease in GSH levels, respectively. Our findings add new evidence of the risks of consuming food grown with urban sewage sludge. However, considering that the amount and type of toxic substances present in urban sewage sludge varies considerably among different sampling areas, further studies are needed to evaluate sludge samples collected from different sources and/or undergoing different types of treatment. Copyright © 2013 Elsevier Inc. All rights reserved.

A comprehensive evaluation of the efficacy of leading oxime therapies in guinea pigs exposed to organophosphorus chemical warfare agents or pesticides

DOE Office of Scientific and Technical Information (OSTI.GOV)

Wilhelm, Christina M., E-mail: wilhelmc@battelle.org; Snider, Thomas H., E-mail: snidert@battelle.org; Babin, Michael C., E-mail: babinm@battelle.org

The currently fielded pre-hospital therapeutic regimen for the treatment of organophosphorus (OP) poisoning in the United States (U.S.) is the administration of atropine in combination with an oxime antidote (2-PAM Cl) to reactivate inhibited acetylcholinesterase (AChE). Depending on clinical symptoms, an anticonvulsant, e.g., diazepam, may also be administered. Unfortunately, 2-PAM Cl does not offer sufficient protection across the range of OP threat agents, and there is some question as to whether it is the most effective oxime compound available. The objective of the present study is to identify an oxime antidote, under standardized and comparable conditions, that offers protection atmore » the FDA approved human equivalent dose (HED) of 2-PAM Cl against tabun (GA), sarin (GB), soman (GD), cyclosarin (GF), and VX, and the pesticides paraoxon, chlorpyrifos oxon, and phorate oxon. Male Hartley guinea pigs were subcutaneously challenged with a lethal level of OP and treated at approximately 1 min post challenge with atropine followed by equimolar oxime therapy (2-PAM Cl, HI-6 DMS, obidoxime Cl{sub 2}, TMB-4, MMB4-DMS, HLö-7 DMS, MINA, and RS194B) or therapeutic-index (TI) level therapy (HI-6 DMS, MMB4-DMS, MINA, and RS194B). Clinical signs of toxicity were observed for 24 h post challenge and blood cholinesterase [AChE and butyrylcholinesterase (BChE)] activity was analyzed utilizing a modified Ellman's method. When the oxime is standardized against the HED of 2-PAM Cl for guinea pigs, the evidence from clinical observations, lethality, quality of life (QOL) scores, and cholinesterase reactivation rates across all OPs indicated that MMB4 DMS and HLö-7 DMS were the two most consistently efficacious oximes. - Highlights: • First comprehensive evaluation of leading AChE oxime reactivators • All oximes are compared against current U.S. therapy 2-PAM Cl. • Relative therapeutic oxime efficacies against OP CWNA and pesticides • Contribution to more effective antidotes for civilian and military populations.« less

Associations of maternal organophosphate pesticide exposure and PON1 activity with birth outcomes in SAWASDEE birth cohort, Thailand

PubMed Central

Naksen, Warangkana; Prapamontol, Tippawan; Mangklabruks, Ampica; Chantara, Somporn; Thavornyutikarn, Prasak; Srinual, Niphan; Panuwet, Parinya; Ryan, P. Barry; Riederer, Anne M.; Barr, Dana Boyd

2015-01-01

Prenatal organophosphate (OP) pesticide exposure has been reported to be associated with adverse birth outcomes and neurodevelopment. However, the mechanisms of toxicity of OP pesticides on human fetal development have not yet been elucidated. Our pilot study birth cohort, the Study of Asian Women and Offspring’s Development and Environmental Exposures (SAWASDEE cohort) aimed to evaluate environmental chemical exposures and their relation to birth outcomes and infant neurodevelopment in 52 pregnant farmworkers in Fang district, Chiang Mai province, Thailand. A large array of data was collected multiple times during pregnancy including approximately monthly urine samples for evaluation of pesticide exposure, three blood samples for pesticide-related enzyme measurements and questionnaire data. This study investigated the changes in maternal acetylcholinesterase (AChE) and paraoxonase 1 (PON1) activities and their relation to urinary diakylphosphates (DAPs), class-related metabolites of OP pesticides, during pregnancy. Maternal AChE, butyrylcholinesterase (BChE) and PON1 activities were measured three times during pregnancy and urinary DAP concentrations were measured, on average, 8 times from enrollment during pregnancy until delivery. Among the individuals in the group with low maternal PON1 activity (n = 23), newborn head circumference was negatively correlated with log10 maternal ΣDEAP and ΣDAP at enrollment (gestational age=12±3 weeks; β = −1.0 cm, p = 0.03 and β = −1.8 cm, p <0.01, respectively) and at 32 weeks pregnancy (β = −1.1 cm, p = 0.04 and β = −2.6 cm, p = 0.01, respectively). Furthermore, among these mothers, newborn birthweight was also negatively associated with log10 maternal ΣDEAP and ΣDAP at enrollment (β = −219.7 g, p = 0.05 and β = −371.3 g, p = 0.02, respectively). Associations between maternal DAP levels and newborn outcomes were not observed in the group of participants with high maternal PON1 activity. Our results support previous findings from US birth cohort studies. This is the first study to report the associations between prenatal OP pesticide exposure and birth outcomes in Thailand. PMID:26186137

Associations of maternal organophosphate pesticide exposure and PON1 activity with birth outcomes in SAWASDEE birth cohort, Thailand.

PubMed

Naksen, Warangkana; Prapamontol, Tippawan; Mangklabruks, Ampica; Chantara, Somporn; Thavornyutikarn, Prasak; Srinual, Niphan; Panuwet, Parinya; Ryan, P Barry; Riederer, Anne M; Barr, Dana Boyd

2015-10-01

Prenatal organophosphate (OP) pesticide exposure has been reported to be associated with adverse birth outcomes and neurodevelopment. However, the mechanisms of toxicity of OP pesticides on human fetal development have not yet been elucidated. Our pilot study birth cohort, the Study of Asian Women and Offspring's Development and Environmental Exposures (SAWASDEE cohort) aimed to evaluate environmental chemical exposures and their relation to birth outcomes and infant neurodevelopment in 52 pregnant farmworkers in Fang district, Chiang Mai province, Thailand. A large array of data was collected multiple times during pregnancy including approximately monthly urine samples for evaluation of pesticide exposure, three blood samples for pesticide-related enzyme measurements and questionnaire data. This study investigated the changes in maternal acetylcholinesterase (AChE) and paraoxonase 1 (PON1) activities and their relation to urinary diakylphosphates (DAPs), class-related metabolites of OP pesticides, during pregnancy. Maternal AChE, butyrylcholinesterase (BChE) and PON1 activities were measured three times during pregnancy and urinary DAP concentrations were measured, on average, 8 times from enrollment during pregnancy until delivery. Among the individuals in the group with low maternal PON1 activity (n=23), newborn head circumference was negatively correlated with log10 maternal ∑DEAP and ∑DAP at enrollment (gestational age=12±3 weeks; β=-1.0 cm, p=0.03 and β=-1.8 cm, p<0.01, respectively) and at 32 weeks pregnancy (β=-1.1cm, p=0.04 and β=-2.6 cm, p=0.01, respectively). Furthermore, among these mothers, newborn birthweight was also negatively associated with log10 maternal ∑DEAP and ∑DAP at enrollment (β=-219.7 g, p=0.05 and β=-371.3g, p=0.02, respectively). Associations between maternal DAP levels and newborn outcomes were not observed in the group of participants with high maternal PON1 activity. Our results support previous findings from US birth cohort studies. This is the first study to report the associations between prenatal OP pesticide exposure and birth outcomes in Thailand. Copyright © 2015 Elsevier Inc. All rights reserved.

Matrix-assisted laser desorption/ionization time-of-flight mass spectrometry (MALDI-TOF MS) for detection and identification of albumin phosphylation by organophosphorus pesticides and G- and V-type nerve agents.

PubMed

John, Harald; Breyer, Felicitas; Thumfart, Jörg Oliver; Höchstetter, Hans; Thiermann, Horst

2010-11-01

Toxic organophosphorus compounds (OPC), e.g., pesticides and nerve agents (NA), are known to phosphylate distinct endogenous proteins in vivo and in vitro. OPC adducts of butyrylcholinesterase and albumin are considered to be valuable biomarkers for retrospective verification of OPC exposure. Therefore, we have detected and identified novel adducts of human serum albumin (HSA) by means of matrix-assisted laser desorption/ionization time-of-flight mass spectrometry (MALDI-TOF MS). Pure albumin and plasma were incubated with numerous pesticides and NA of the V- and G-type in different molar ratios. Samples were prepared either by sodium dodecyl sulfate-polyacrylamide gel electrophoresis followed by in-gel enzymatic cleavage using endoproteinase Glu-C (Glu-C) or by combining highly albumin-selective affinity extraction with ultrafiltration followed by reduction, carbamidomethylation, and enzymatic cleavage (Glu-C) prior to MALDI-TOF MS analysis. Characteristic mass shifts for phosphylation revealed tyrosine adducts at Y(411) (Y(401)KFQNALLVRY(411)TKKVPQVSTPTLVE(425)), Y(148) and Y(150) (I(142)ARRHPY(148)FY(150)APE(153), single and double labeled), and Y(161) (L(154)LFFAKRY(161)KAAFTE(167)) produced by original NA (tabun, sarin, soman, cyclosarin, VX, Chinese VX, and Russian VX) as well as by chlorpyrifos-oxon, diisopropyl fluorophosphate (DFP), paraoxon-ethyl (POE), and profenofos. MALDI-MS/MS of the single-labeled I(142)-E(153) peptide demonstrated that Y(150) was phosphylated with preference to Y(148). Aged albumin adducts were not detected. The procedure described was reproducible and feasible for detection of adducts at the most reactive Y(411)-residue (S/N ≥ 3) when at least 1% of total albumin was labeled. This was achieved by incubating plasma with molar HSA/OPC ratios ranging from approximately 1:0.03 (all G-type NA, DFP, and POE) to 1:3 (V-type NA, profenofos). Relative signal intensity of the Y(411) adduct correlated well with the spotted relative molar amount underlining the usefulness for quantitative adduct determination. In conclusion, the current analytical design exhibits potential as a verification tool for high-dose exposure.

The Leu-Arg-Glu (LRE) adhesion motif in proteins of the neuromuscular junction with special reference to proteins of the carboxylesterase/cholinesterase family.

PubMed

Johnson, Glynis; Moore, Samuel W

2013-09-01

Short linear motifs confer evolutionary flexibility on proteins as they can be added with relative ease allowing the acquisition of new functions. Such motifs may mediate a variety of signalling functions. The adhesion-mediating Leu-Arg-Glu (LRE) motif is enriched in laminin beta 2, and has been observed in other proteins, including members of the carboxylesterase/cholinesterase family. It acts as a stop signal for growing axons in the developing neuromuscular junction, binding to the voltage-gated calcium channel. In this bioinformatic analysis, we have investigated the presence of the motif in proteins of the neuromuscular junction, and have also examined its structural position and potential for ligand interaction, as well as phylogenetic conservation, in the carboxylesterase/cholinesterase family. The motif was observed to occur with a significantly higher frequency than expected in the UniProt/Swiss-Prot database, as well as in four individual species (human, mouse, Caenorhabditis elegans and Drosophila melanogaster). Examination of its presence in neuromuscular junction proteins showed it to be enriched in certain proteins of the synaptic basement membrane, including laminin, agrin, acetylcholinesterase and tenascin. A highly significant enrichment was observed in cytoskeletal proteins, particularly intermediate filament proteins and members of the spectrin family. In the carboxylesterase/cholinesterase family, the motif was observed in four conserved positions in the protein structure. It is present in the majority of mammalian acetylcholinesterases, as well as acetylcholinesterases from electric fish and a number of invertebrates. In insects, it is present in the ace-2, rather than in the synaptic ace-1, enzyme. It is also observed in the cholinesterase-like adhesion molecules (neuroligins, neurotactin and glutactin). It is never seen in butyrylcholinesterases, which do not mediate cell adhesion. In conclusion, the significant enrichment of the motif in certain classes of protein, as well as its conserved presence and structural positioning in one protein family, suggests that it has specific functions both in cell adhesion in the neuromuscular junction and in maintaining the structural integrity of the cytoskeleton. Copyright © 2013 Elsevier Inc. All rights reserved.

Comparative study on the inhibitory effect of caffeic and chlorogenic acids on key enzymes linked to Alzheimer's disease and some pro-oxidant induced oxidative stress in rats' brain-in vitro.

PubMed

Oboh, Ganiyu; Agunloye, Odunayo M; Akinyemi, Ayodele J; Ademiluyi, Adedayo O; Adefegha, Stephen A

2013-02-01

This study sought to investigate and compare the interaction of caffeic acid and chlorogenic acid on acetylcholinesterase (AChE) and butyrylcholinesterase (BChE), and some pro-oxidants (FeSO(4), sodium nitroprusside and quinolinic acid) induced oxidative stress in rat brain in vitro. The result revealed that caffeic acid and chlorogenic acid inhibited AChE and BChE activities in dose-dependent manner; however, caffeic acid had a higher inhibitory effect on AChE and BChE activities than chlorogenic acid. Combination of the phenolic acids inhibited AChE and BChE activities antagonistically. Furthermore, pro-oxidants such as, FeSO(4), sodium nitroprusside and quinolinic acid caused increase in the malondialdehyde (MDA) contents of the brain which was significantly decreased dose-dependently by the phenolic acids. Inhibition of AChE and BChE activities slows down acetylcholine and butyrylcholine breakdown in the brain. Therefore, one possible mechanism through which the phenolic acids exert their neuroprotective properties is by inhibiting AChE and BChE activities as well as preventing oxidative stress-induced neurodegeneration. However, esterification of caffeic acid with quinic acid producing chlorogenic acid affects these neuroprotective properties.

In Vitro Screening of Three Indian Medicinal Plants for Their Phytochemicals, Anticholinesterase, Antiglucosidase, Antioxidant, and Neuroprotective Effects.

PubMed

Penumala, Mohan; Zinka, Raveendra Babu; Shaik, Jeelan Basha; Amooru Gangaiah, Damu

2017-01-01

Cooccurrence of Diabetes Mellitus and Alzheimer's disease in elder people prompts scientists to develop multitarget agents that combat causes and symptoms of both diseases simultaneously. In line with this modern paradigm and as a follow-up to our previous studies, the present study is designed to investigate the crude methanolic extracts and subsequent CHCl 3 , n -BuOH, and H 2 O fractions of Acalypha alnifolia , Pavetta indica, and Ochna obtusata for their inhibitory activities towards specific targets involved in AD and DM, namely, acetylcholinesterase, butyrylcholinesterase, and α -glucosidase ( α -Glc). The methanolic extract and its derived chloroform fractions exhibited remarkable inhibitory capacities with IC 50 values being found at the μ g/mL level. Further studies on most active chloroform fractions presented a prominent ability to scavenge DPPH and ABTS reactive species and highest neuroprotective effect against H 2 O 2 induced cell injury. Phytochemical analysis showed a large amount of phenolics, flavonoids, and terpenoids in active fractions. In conclusion, A. alnifolia , P. indica, and O. obtusata could be promising sources for the treatment of AD and DM since these fractions induced significant anticholinesterase, antidiabetic, antioxidant, and neuroprotection effects attributable to phenolic, flavonoid, and terpenoid contents and encourage further studies for development of multifunctional therapeutic agent for AD and DM dual therapy.

Effect of environmental contaminants in the Mississippi River Basin on carboxylesterases from four aquatic species

DOE Office of Scientific and Technical Information (OSTI.GOV)

Jaiswal, R.; Huang, T.; Obih, P.

1995-12-31

The objectives of this study are to investigate the sensitivity of different classes of esterases in various aquatic species to environmental contaminants and the possible use of these enzymes as biomarkers for monitoring the effects of pollutants. Acetylcholinesterase (AChE), butyrylcholinesterase (BuChE), and the non-specific carboxylesterases (CaE) were analyzed in three fish species, Ictiobus bubalus (small mouth buffalo), Ictiobus cyprinellus (big mouth buffalo) and Lepisosteus oculatus (spotted gar) and the green tree frog, Hyla cinerea. These samples were collected from the Devil`s Swamp Site (DSS), an industrial site known to be highly contaminated at the Mississippi River Basin, and Lake Tunica,more » a nonindustrial site. ACHE and BuChE activities in the subcellular fractions of liver and brain were significantly lower in fishes and frogs obtained from DSS when compared to the same species obtained from Tunica swamp site. The greatest decrease was observed with ACHE activity in the liver and brain of Ictiobus bubalus from DSS. CaE activity analyzed with p-nitrophenyl acetate was found to be significantly lower in the liver of all three fish species collected from DSS when compared to the same fish species obtained from the Tunica swamp site.« less

Acetylcholine-hydrolyzing activities in soluble brain fraction: Characterization with reversible and irreversible inhibitors.

PubMed

Estévez, Jorge; Selva, Verónica; Benabent, Mónica; Mangas, Iris; Sogorb, Miguel Ángel; Vilanova, Eugenio

2016-11-25

Some effects of organophosphorus compounds (OPs) esters cannot be explained through actions on currently recognized targets acetylcholinesterase or neuropathy target esterase (NTE). In soluble chicken brain fraction, three components (Eα, Eβ and Eγ) of pheny lvalerate esterase activity (PVase) were kinetically discriminated and their relationship with acetylcholine-hydrolyzing activity (cholinesterase activity) were studied in previous works. In this work, four enzymatic components (CS1, CS2, CS3 and CS4) of cholinesterase activity have been discriminated in soluble fraction, according to their sensitivity to irreversible inhibitors mipafox, paraoxon, PMSF and iso-OMPA and to reversible inhibitors ethopropazine and BW284C51. Cholinesterase component CS1 can be related to the Eα component of PVase activity and identified as butyrylcholinesterase (BuChE). No association and similarities can be stablished among the other PVase component (Eβ and Eγ) with the other cholinesterase components (CS2, CS3, CS4). The kinetic analysis has allowed us to stablish a method for discriminating the enzymatic component based on a simple test with two inhibitors. It can be used as biomarker in toxicological studies and for monitoring these cholinesterase components during isolation and molecular identification processes, which will allow OP toxicity to be understood by a multi-target approach. Copyright © 2016 Elsevier Ireland Ltd. All rights reserved.

Profiling Cholinesterase Adduction: A High-Throughput Prioritization Method for Organophosphate Exposure Samples

PubMed Central

Carter, Melissa D.; Crow, Brian S.; Pantazides, Brooke G.; Watson, Caroline M.; deCastro, B. Rey; Thomas, Jerry D.; Blake, Thomas A.; Johnson, Rudolph C.

2017-01-01

A high-throughput prioritization method was developed for use with a validated confirmatory method detecting organophosphorus nerve agent exposure by immunomagnetic separation-HPLC-MS/MS. A ballistic gradient was incorporated into this analytical method in order to profile unadducted butyrylcholinesterase (BChE) in clinical samples. With Zhang, et al. 1999’s Z′-factor of 0.88 ± 0.01 (SD) of control analytes and Z-factor of 0.25 ± 0.06 (SD) of serum samples, the assay is rated an “excellent assay” for the synthetic peptide controls used and a “double assay” when used to prioritize clinical samples. Hits, defined as samples containing BChE Ser-198 adducts or no BChE present, were analyzed in a confirmatory method for identification and quantitation of the BChE adduct, if present. The ability to prioritize samples by highest exposure for confirmatory analysis is of particular importance in an exposure to cholinesterase inhibitors such as organophosphorus nerve agents where a large number of clinical samples may be collected. In an initial blind screen, 67 out of 70 samples were accurately identified giving an assay accuracy of 96% and yielded no false negatives. The method is the first to provide a high-throughput prioritization assay for profiling adduction of Ser-198 BChE in clinical samples. PMID:23954929

Rivastigmine in the treatment of Alzheimer’s disease: an update

PubMed Central

Onor, Maria Luisa; Trevisiol, Marianna; Aguglia, Eugenio

2007-01-01

Alzheimer’s disease is the most common form of dementia in industrialized countries. In the European Union, about 54% of dementia cases are believed to be due to Alzheimer’s disease. The condition is an age-related neurodegenerative disorder characterized by multiple cognitive deficiencies, including loss of memory, judgment, and comprehension. These manifestations are accompanied by behavioral and mood disturbances. Although no cure has yet been discovered for Alzheimer’s disease, symptomatic therapies are now widely available and offer significant relief to patients and benefits to caregivers in terms of reduced care burden. At the start of the 21st century, health technology assessments recommended three agents for the symptomatic treatment of mild to moderate Alzheimer disease: rivastigmine, donepezil, and galantamine. Rivastigmine (Exelon®, Novartis Basel—Switzerland) is a slowly reversible inhibitor of acetylcholinesterase (AChE) and butyrylcholinesterase (BuChE), while donepezil (Aricept®, Pfizer, New York, USA) and galantamine (Reminyl®, Janssen, New Jersey,USA) show no functional inhibition of BuChE, and are considered AChE-selective, rapidly-reversible inhibitors. The efficacy of all three agents has been evaluated in large, double-blind, placebo-controlled clinical trials of up to 6 months’ duration. Rivastigmine treatment in mild to moderate Alzheimer’s disease improves cognition, activities of daily living, and global function. PMID:18044073

Pharmacokinetic Modeling to Simulate the Concentration-Time Profiles After Dermal Application of Rivastigmine Patch.

PubMed

Nozaki, Sachiko; Yamaguchi, Masayuki; Lefèvre, Gilbert

2016-07-01

Rivastigmine is an inhibitor of acetylcholinesterases and butyrylcholinesterases for symptomatic treatment of Alzheimer disease and is available as oral and transdermal patch formulations. A dermal absorption pharmacokinetic (PK) model was developed to simulate the plasma concentration-time profile of rivastigmine to answer questions relative to the efficacy and safety risks after misuse of the patch (e.g., longer application than 24 h, multiple patches applied at the same time, and so forth). The model comprised 2 compartments which was a combination of mechanistic dermal absorption model and a basic 1-compartment model. The initial values for the model were determined based on the physicochemical characteristics of rivastigmine and PK parameters after intravenous administration. The model was fitted to the clinical PK profiles after single application of rivastigmine patch to obtain model parameters. The final model was validated by confirming that the simulated concentration-time curves and PK parameters (Cmax and area under the drug plasma concentration-time curve) conformed to the observed values and then was used to simulate the PK profiles of rivastigmine. This work demonstrated that the mechanistic dermal PK model fitted the clinical data well and was able to simulate the PK profile after patch misuse. Copyright © 2016 American Pharmacists Association®. Published by Elsevier Inc. All rights reserved.

Synthesis of Amide and Ester Derivatives of Cinnamic Acid and Its Analogs: Evaluation of Their Free Radical Scavenging and Monoamine Oxidase and Cholinesterase Inhibitory Activities.

PubMed

Takao, Koichi; Toda, Kazuhiro; Saito, Takayuki; Sugita, Yoshiaki

2017-01-01

A series of cinnamic acid derivatives, amides (1-12) and esters (13-22), were synthesized, and structure-activity relationships for antioxidant activity, and monoamine oxidases (MAO) A and B, acetylcholinesterase, and butyrylcholinesterase (BChE) inhibitory activities were analyzed. Among the synthesized compounds, compounds 1-10, 12-18, and rosmarinic acid (23), which contained catechol, o-methoxyphenol or 5-hydroxyindole moieties, showed potent 1,1-diphenyl-2-picrylhydrazyl (DPPH) free radical scavenging activity. Compounds 9-11, 15, 17-22 showed potent and selective MAO-B inhibitory activity. Compound 20 was the most potent inhibitor of MAO-B. Compounds 18 and 21 showed moderate BChE inhibitory activity. In addition, compound 18 showed potent antioxidant activity and MAO-B inhibitory activity. In a comparison of the cinnamic acid amides and esters, the amides exhibited more potent DPPH free radical scavenging activity, while the esters showed stronger inhibitory activities against MAO-B and BChE. These results suggested that cinnamic acid derivatives such as compound 18, p-coumaric acid 3,4-dihydroxyphenethyl ester, and compound 20, p-coumaric acid phenethyl ester, may serve as lead compounds for the development of novel MAO-B inhibitors and candidate lead compounds for the prevention or treatment of Alzheimer's disease.

Nature as a source of metabolites with cholinesterase-inhibitory activity: an approach to Alzheimer's disease treatment.

PubMed

Pinho, Brígida R; Ferreres, Federico; Valentão, Patrícia; Andrade, Paula B

2013-12-01

Alzheimer's disease (AD) is the most common cause of dementia, being responsible for high healthcare costs and familial hardships. Despite the efforts of researchers, no treatment able to delay or stop AD progress exists. Currently, the available treatments are only symptomatic, cholinesterase inhibitors being the most widely used drugs. Here we describe several natural compounds with anticholinesterase (acetylcholinesterase and butyrylcholinesterase) activity and also some synthetic compounds whose structures are based on those of natural compounds. Galantamine and rivastigmine are two cholinesterase inhibitors used in therapeutics: galantamine is a natural alkaloid that was extracted for the first time from Galanthus nivalis L., while rivastigmine is a synthetic alkaloid, the structure of which is modelled on that of natural physostigmine. Alkaloids include a high number of compounds with anticholinesterases activity at the submicromolar range. Quinones and stilbenes are less well studied regarding cholinesterase inhibition, although some of them, such as sargaquinoic acid or (+)-α-viniferin, show promising activity. Among flavonoids, flavones and isoflavones are the most potent compounds. Xanthones and monoterpenes are generally weak cholinesterase inhibitors. Nature is an almost endless source of bioactive compounds. Several natural compounds have anticholinesterase activity and others can be used as leader compounds for the synthesis of new drugs. © 2013 Royal Pharmaceutical Society.

Cholinesterase inhibitor (Altenuene) from an endophytic fungus Alternaria alternata: optimization, purification and characterization.

PubMed

Bhagat, J; Kaur, A; Kaur, R; Yadav, A K; Sharma, V; Chadha, B S

2016-10-01

The aim of this study was to screen endophytic fungi isolated from Vinca rosea for their potential to produce acetylcholinesterase (AChE) inhibitors. Endophytic fungi isolated from V. rosea (Catharanthus roseus), were screened for AChE inhibitor production using Ellman's method. Maximum inhibition against AChE (78%) was observed in an isolate VS-10, identified to be Alternaria alternata on morphological and molecular basis. The isolate also inhibited butyrylcholinesterase (73%). Significant increase (1·3 fold) was achieved after optimization of process parameters using one variable at time approach. The inhibitor was purified using chromatographic techniques. The structure elucidation of the inhibitor was carried out using spectroscopic techniques and was identified to be 'altenuene'. The purified inhibitor possessed antioxidant potential as revealed by dot blot assay. The insecticidal potential of purified inhibitor was evaluated by feeding Spodoptora litura on diet amended with inhibitor. It evinced significant larval mortality. Endophytic A. alternata can serve as a source of dual cholinesterase inhibitor 'altenuene' with significant antioxidant and insecticidal activity. This is the first report on acetylcholinestearse inhibitory activity of altenuene. Alternaria alternata has the potential to produce a dual ChE inhibitor with antioxidant activity useful in the treatment of neurodegenerative disorders and in agriculture as biocontrol agent. © 2016 The Society for Applied Microbiology.

Antioxidant and anticholinesterase activities of eleven edible plants.

PubMed

Boğa, Mehmet; Hacıbekiroğlu, Işıl; Kolak, Ufuk

2011-03-01

Consumers have become more interested in beneficial effects of vegetables, fruits, and tea to protect their health. The antioxidant potential and anticholinesterase activity of eleven edible plants were investigated. The dichloromethane, ethanol and water extracts prepared from celery [Apium graveolens L. (Umbelliferae)], Jerusalem artichoke [Helianthus tuberosus L. (Compositae)], spinach [Spinacia oleracea L. (Chenopodiaceae)], chard [Beta vulgaris L. var. cicla (Chenopodiaceae)], purslane [Portulaca oleracea L. (Portulacaceae)], ispit, or borage [Trachystemon orientale (L.) G. Don (Boraginaceae)], garden rocket [Eruca sativa Mill. (Brassicaceae)], red cabbage [Brassica oleracea L. var. capitata f. rubra DC. (Cruciferae)], lime flower [Tilia tomentosa Moench (Tiliaceae)], cinnamon [Cinnamomum cassia Presl. (Lauraceae)], and rosehip [Rosa canina L. (Rosaceae)], were tested to determine their antioxidant and anticholinesterase activities by using CUPRAC (cupric reducing antioxidant capacity) and Ellman methods, respectively, for the first time. As a result, the dichloromethane, ethanol and water extracts of cinnamon showed the best antioxidant effect among the extracts of the tested plants. The ethanol extract of cinnamon exhibited 63.02% inhibition against acetylcholinesterase and 85.11% inhibition against butyrylcholinesterase (BChE) at 200 µg/mL concentration while the dichloromethane extract of garden rocket possessed the highest inhibition (91.27%) against BChE among all the tested extracts. This study indicated that the ethanol extract of cinnamon may be a new potential resource of natural antioxidant and anticholinesterase compounds.

Antioxidant, Antityrosinase, Anticholinesterase, and Nitric Oxide Inhibition Activities of Three Malaysian Macaranga Species

PubMed Central

Abas, Faridah; Ahmad, Syahida; Shaari, Khozirah; Khamis, Shamsul; Lajis, N. H.

2013-01-01

The methanol extracts of three Macaranga species (M. denticulata, M. pruinosa, and M. gigantea) were screened to evaluate their total phenolic contents and activities as cholinesterase inhibitors, nitric oxide (NO) production inhibitors, tyrosinase inhibitors, and antioxidants. The bark of M. denticulata showed the highest total phenolic content (2682 mg gallic acid equivalent (GAE)/100 g) and free radical scavenging activity (IC50 = 0.063 mg/mL). All of the samples inhibited linoleic acid peroxidation by greater than 80%, with the leaves of M. gigantea exhibiting the highest inhibition of 92.21%. Most of the samples exhibited significant antioxidant potential. The bark of M. denticulata and the leaves of both M. pruinosa and M. gigantea exhibited greater than 50% tyrosinase inhibition, with the bark of M. denticulata having the highest percentage of inhibition (68.7%). The bark and leaves of M. denticulata exhibited greater than 50% inhibition (73.82% and 54.50%, resp.) of the acetylcholinesterase enzyme (AChE), while none of the samples showed any significant inhibition of butyrylcholinesterase (BChE). Only the bark of M. denticulata and M. gigantea displayed greater than 50% inhibition of nitric oxide production in cells (81.79% and 56.51%, resp.). These bioactivities indicate that some Macaranga spp. have therapeutic potential in medicinal research. PMID:24319356

Chemical constituents of essential oil of endemic Rhanterium suaveolens Desf. growing in Algerian Sahara with antibiofilm, antioxidant and anticholinesterase activities.

PubMed

Chemsa, Ahmed Elkhalifa; Erol, Ebru; Öztürk, Mehmet; Zellagui, Amar; Özgür, Ceylan; Gherraf, Noureddine; Duru, Mehmet Emin

2016-09-01

Twenty compounds were detected in the essential oil of Rhanterium suaveolens representing 98.01% of the total oil content. Perillaldehyde (45.79%), caryophyllene oxide (24.82%) and β-cadinol (5.61%) were identified as the main constituents. In β-carotene-linoleic acid assay, both the oil and the methanol extract exhibited good lipid peroxidation inhibition activity, with IC50 values of 17.97 ± 5.40 and 11.55 ± 3.39 μg/mL, respectively. In DPPH and CUPRAC assays, however, the methanol extract exhibited a good antioxidant activity. The highest antibiofilm activity has been found 50.30% against Staphylococcus epidermidis (MU 30) at 20 μg/mL for essential oil and 58.34% against Micrococcus luteus (NRRL B-4375) at 25 mg/mL concentration for methanol extract. The in vitro anticholinesterase activity of methanol extract showed a moderate acetylcholinesterase inhibitory (IC50 = 168.76 ± 0.62 μg/mL) and good butyrylcholinesterase inhibitory (IC50 = 54.79 ± 1.89 μg/mL) activities. The essential oil was inactive against both enzymes.

Novel Tacrine-Based Pyrano[3',4':5,6]pyrano[2,3-b]quinolinones: Synthesis and Cholinesterase Inhibitory Activity.

PubMed

Hariri, Roshanak; Afshar, Zahra; Mahdavi, Mohammad; Safavi, Maliheh; Saeedi, Mina; Najafi, Zahra; Sabourian, Reyhaneh; Karimpour-Razkenari, Elahe; Edraki, Najmeh; Moghadam, Farshad Homayouni; Shafiee, Abbas; Khanavi, Mahnaz; Akbarzadeh, Tahmineh

2016-12-01

In order to develop effective anti-cholinesterase compounds, a novel series of pyrano[3',4':5,6]pyrano[2,3-b]quinolinones were designed, synthesized, and evaluated in vitro against acetylcholinesterase (AChE) and butyrylcholinesterase (BChE). All derivatives showed very good AChE inhibitory (AChEI) activity (IC 50  = 0.37-5.62 μM) compared with rivastigmine (IC 50  = 11.07 μM). Among them, 11-amino-12-(2,3-dichlorophenyl)-3-methyl-7,8,9,10-tetrahydropyrano[3',4':5,6]pyrano[2,3-b]quinolin-1(12H)-one (6f) displayed the best inhibitory activity. However, most of the synthesized compounds showed no anti-BChE activity and compounds 6b and 6f were found to be only moderate inhibitors. The most potent anti-AChE compound 6f had low and moderate inhibitory activity and neuroprotective effects against beta-secretase (BACE1) and oxidative stress-induced cell death, respectively. Also, kinetic and molecular docking studies of binding interactions elucidated that compound 6f bound to both the catalytic anionic site (CAS) and peripheral anionic site (PAS) of AChE. © 2016 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

Antioxidant, antityrosinase, anticholinesterase, and nitric oxide inhibition activities of three malaysian macaranga species.

PubMed

Mazlan, Nor Aishah; Mediani, Ahmed; Abas, Faridah; Ahmad, Syahida; Shaari, Khozirah; Khamis, Shamsul; Lajis, N H

2013-01-01

The methanol extracts of three Macaranga species (M. denticulata, M. pruinosa, and M. gigantea) were screened to evaluate their total phenolic contents and activities as cholinesterase inhibitors, nitric oxide (NO) production inhibitors, tyrosinase inhibitors, and antioxidants. The bark of M. denticulata showed the highest total phenolic content (2682 mg gallic acid equivalent (GAE)/100 g) and free radical scavenging activity (IC50 = 0.063 mg/mL). All of the samples inhibited linoleic acid peroxidation by greater than 80%, with the leaves of M. gigantea exhibiting the highest inhibition of 92.21%. Most of the samples exhibited significant antioxidant potential. The bark of M. denticulata and the leaves of both M. pruinosa and M. gigantea exhibited greater than 50% tyrosinase inhibition, with the bark of M. denticulata having the highest percentage of inhibition (68.7%). The bark and leaves of M. denticulata exhibited greater than 50% inhibition (73.82% and 54.50%, resp.) of the acetylcholinesterase enzyme (AChE), while none of the samples showed any significant inhibition of butyrylcholinesterase (BChE). Only the bark of M. denticulata and M. gigantea displayed greater than 50% inhibition of nitric oxide production in cells (81.79% and 56.51%, resp.). These bioactivities indicate that some Macaranga spp. have therapeutic potential in medicinal research.

Anticholinesterase activity of 7-methoxyflavones isolated from Kaempferia parviflora.

PubMed

Sawasdee, Pattara; Sabphon, Chalisa; Sitthiwongwanit, Duangporn; Kokpol, Udom

2009-12-01

The rhizome of Kaempferia parviflora or kra-chai-dum (in Thai) is used traditionally as a folk medicine. The preliminary cholinesterase inhibitory screening of this plant extract exhibited significant acetylcholinesterase (AChE) and butyrylcholinesterase (BChE) inhibitory activities. Thirteen known methoxyflavones (1-13) were isolated and their structures were completely elucidated based on NMR analysis and compared with literature reports. Minor compounds 12-13 were reported for the first time from this species. The cholinesterase inhibitory test results showed that the highest potential inhibitors toward AChE and BChE were 5,7,4'-trimethoxyflavone (6) and 5,7-dimethoxyflavone (7), respectively, with the percentage inhibitory activity varying over 43-85%. The structure-activity relationship study led to the conclusion that compounds bearing 5,7-dimethoxy groups and a free substituent at C-3 had a significant inhibitory effect at a concentration of 0.1 mg/mL, but those bearing a 5-hydroxyl group reduced the inhibitory potency. On the other hand, flavones bearing a 3'- or 5'-methoxy group did not influence the inhibitory effect. Interestingly, 5,7-dimethoxyflavone (7) exhibited strong selectivity for BChE over AChE which may be of great interest to modify as a treatment agent for Alzheimer's disease. Copyright (c) 2009 John Wiley & Sons, Ltd.

New beverages of lemon juice enriched with the exotic berries maqui, açaı́, and blackthorn: bioactive components and in vitro biological properties.

PubMed

Gironés-Vilaplana, Amadeo; Valentão, Patrícia; Moreno, Diego A; Ferreres, Federico; García-Viguera, Cristina; Andrade, Paula B

2012-07-04

Following previous research on lemon juice enriched with berries, the aim of this work was to design new blends based on lemon juice mixed with different edible berries of exotic and national origin: maqui ( Aristotelia chilensis (Molina) Stuntz), açaı́ ( Euterpe oleracea Mart.), and blackthorn ( Prunus spinosa L.). The phytochemical characterization of controls and blends was performed by HPLC-DAD-ESI/MS(n). Their antioxidant capacity against DPPH, superoxide, and hydroxyl radicals and hypochlorous acid and their potential to inhibit cholinesterases were also assessed. The profiling of the red fruits and lemon revealed a wide range of bioactive phenolics. The novel beverage based on lemon juice and maqui berry (LM) was the most interesting blend in terms of antioxidant capacity. Berry control samples displayed reduced effects on acetylcholinesterase and butyrylcholinesterase, the lemon juice control being always the most active. This activity was also remarkable for lemon-blackthorn (LB) and lemon-açaı́ (LA) blends, the last being the most effective inhibitor of cholinesterases among all samples. The results suggested that lemon juice enriched with berries could be of potential interest in the design of new drinks with a nutritive related function on health for chronic diseases.

Organophosphorus poisoning (acute).

PubMed

2007-03-01

Acute organophosphorus poisoning occurs after dermal, respiratory, or oral exposure to either low-volatility pesticides (e.g. chlorpyrifos, dimethoate) or high-volatility nerve gases (e.g. sarin, tabun). Most cases occur in resource-poor countries as a result of occupational or deliberate exposure to organophosphorus pesticides. We conducted a systematic review and aimed to answer the following clinical question: What are the effects of treatments for acute organophosphorus poisoning? We searched: Medline, Embase, The Cochrane Library and other important databases up to August 2006 (Clinical Evidence reviews are updated periodically, please check our website for the most up-to-date version of this review). We included harms alerts from relevant organisations such as the US Food and Drug Administration (FDA) and the UK Medicines and Healthcare products Regulatory Agency (MHRA). We found 22 systematic reviews, RCTs, or observational studies that met our inclusion criteria. We performed a GRADE evaluation of the quality of evidence for interventions. In this systematic review we present information relating to the effectiveness and safety of the following interventions: activated charcoal, alpha2 adrenergic receptor agonists, atropine, benzodiazepines, butyrylcholinesterase replacement therapy, cathartics, extracorporeal clearance, gastric lavage, glycopyrronium bromide, ipecacuanha, magnesium sulphate, milk or other home remedies, N-methyl-D-aspartate receptor antagonists, organophosphorus hydrolases, oximes, sodium bicarbonate, washing the poisoned person and removing contaminated clothing.

Organophosphorus poisoning (acute).

PubMed

Blain, Peter G

2011-05-17

Acetylcholinesterase inhibition by organophosphorus pesticides or organophosphate nerve agents can cause acute parasympathetic system dysfunction, muscle weakness, seizures, coma, and respiratory failure. Prognosis depends on the dose and relative toxicity of the specific compound, as well as pharmacokinetic factors. We conducted a systematic review and aimed to answer the following clinical question: What are the effects of treatments for acute organophosphorus poisoning? We searched: Medline, Embase, The Cochrane Library, and other important databases up to April 2010 (Clinical Evidence reviews are updated periodically; please check our website for the most up-to-date version of this review). We included harms alerts from relevant organisations such as the US Food and Drug Administration (FDA) and the UK Medicines and Healthcare products Regulatory Agency (MHRA). We found 62 systematic reviews, RCTs, or observational studies that met our inclusion criteria. We performed a GRADE evaluation of the quality of evidence for interventions. In this systematic review we present information relating to the effectiveness and safety of the following interventions: activated charcoal (single or multiple doses), alpha(2) adrenergic receptor agonists, atropine, benzodiazepines, butyrylcholinesterase replacement therapy, cathartics, extracorporeal clearance, gastric lavage, glycopyrronium bromide (glycopyrrolate), ipecacuanha (ipecac), magnesium sulphate, milk or other home remedy immediately after ingestion, N-methyl-D-aspartate receptor antagonists, organophosphorus hydrolases, oximes, removing contaminated clothes and washing the poisoned person, and sodium bicarbonate.

Recent developments in the synthesis of acetylcholinesterase inhibitors.

PubMed

Marco, José L; Carreiras, M Carmo

2003-09-01

The acetylcholinesterase (AChE) and butyrylcholinesterase (BuChE) inhibitory activities of a series of pyrano[2,3-b]quinolines (2, 3), [1,8]naphthyridines (5, 6), 4-amino-2,3-diaryl-5,6,7,8-tetrahydrofuro[2,3-b]quinolines (11-13)/ 4-amino-6,7,8,9-tetrahydro-2,3-diphenyl-5H-cyclohepta[e]furo[2,3-b]pyridine (14), 4-amino-5,6,7,8-tetrahydro-2,3-diphenylthieno[2,3-b]quinoline (15)/ 4-amino-6,7,8,9-tetrahydro-2,3-diphenyl-5H-cyclohepta[e]thieno[2,3-b]pyridine (16) are described. These compounds are tacrine analogues that have been prepared from readily available polyfunctionalized ethyl [6-amino-5-cyano-4H-pyran]-3-carboxylates (9, 10), ethyl [6-amino-5-cyanopyridine]-3-carboxylates (7, 8), 2-amino-3-cyano-4,5-diarylfurans (17-19) and 2-amino-3-cyano-4,5-diphenylthiophene (20) via Friedländer condensation with selected ketones. These compounds are competitive and, in a few cases, non-competitive inhibitors for AChE, the most potent being compound (14), though three-fold less active than tacrine. The BuChE inhibitory activity is only significant in compounds 11 and 14, ten-fold less active than tacrine. Furthermore, the products 12 and 13 are selective and moderate AChE inhibitors.

Evolution of cholinesterases in the animal kingdom.

PubMed

Pezzementi, Leo; Chatonnet, Arnaud

2010-09-06

Cholinesterases emerged from a family of enzymes and proteins with adhesion properties. This family is absent in plants and expanded in multicellular animals. True cholinesterases appeared in triploblastic animals together with the cholinergic system. Lineage specific duplications resulted in two acetylcholinesterases in most hexapods and in up to four genes in nematodes. In vertebrates the duplication leading to acetylcholinesterase (AChE) and butyrylcholinesterase (BChE) is now considered to be an ancient event which occurred before the split of osteichthyes. The product of one or the other of the paralogues is responsible for the physiological hydrolysis of acetylcholine, depending on the species lineage and tissue considered. The BChE gene seems to have been lost in some fish lineages. The complete genome of amphioxus (Branchiostoma floridae: cephalochordate) contains a large number of duplicated genes or pseudogenes of cholinesterases. Sequence comparison and tree constructions raise the question of considering the atypical ChE studied in this organism as a representative of ancient BChE. Thus nematodes, arthropods, annelids, molluscs, and vertebrates typically possess two paralogous genes coding for cholinesterases. The origin of the duplication(s) is discussed. The mode of attachment through alternative C-terminal coding exons seems to have evolved independently from the catalytic part of the gene. Copyright (c) 2010 Elsevier Ireland Ltd. All rights reserved.

Protease inhibitors and indoleamines selectively inhibit cholinesterases in the histopathologic structures of Alzheimer disease.

PubMed Central

Wright, C I; Guela, C; Mesulam, M M

1993-01-01

Neurofibrillary tangles and amyloid plaques express acetylcholinesterase and butyrylcholinesterase activity in Alzheimer disease. We previously reported that traditional acetylcholinesterase inhibitors such as BW284C51, tacrine, and physostigmine were more potent inhibitors of the acetylcholinesterase in normal axons and cell bodies than of the acetylcholinesterase in plaques and tangles. We now report that the reverse pattern is seen with indoleamines (such as serotonin and its precursor 5-hydroxytryptophan), carboxypeptidase inhibitor, and the nonspecific protease inhibitor bacitracin. These substances are more potent inhibitors of the cholinesterases in plaques and tangles than of those in normal axons and cell bodies. These results show that the enzymatic properties of plaque and tangle-associated cholinesterases diverge from those of normal axons and cell bodies. The selective susceptibility to bacitracin and carboxypeptidase inhibitor indicates that the catalytic sites of plaque and tangle-bound cholinesterases are more closely associated with peptidase or protease-like properties than the catalytic sites of cholinesterases in normal axons and cell bodies. This shift in enzymatic affinity may lead to the abnormal protein processing that is thought to play a major role in the pathogenesis of Alzheimer disease. The availability of pharmacological and dietary means for altering brain indoleamines raises therapeutic possibilities for inhibiting the abnormal cholinesterase activity associated with Alzheimer disease. Images PMID:8421706

Development of acetophenone ligands as potential neuroimaging agents for cholinesterases.

PubMed

Jollymore-Hughes, Courtney T; Pottie, Ian R; Martin, Earl; Rosenberry, Terrone L; Darvesh, Sultan

2016-11-01

Association of cholinesterase with β-amyloid plaques and tau neurofibrillary tangles in Alzheimer's disease offers an opportunity to detect disease pathology during life. Achieving this requires development of radiolabelled cholinesterase ligands with high enzyme affinity. Various fluorinated acetophenone derivatives bind to acetylcholinesterase with high affinity, including 2,2,2-trifluoro-1-(3-dimethylaminophenyl)ethanone (1) and 1-(3-tert-butylphenyl)-2,2,2-trifluoroethanone (2). Such compounds also offer potential for incorporation of radioactive fluorine ( 18 F) for Positron Emission Tomography (PET) imaging of cholinesterases in association with Alzheimer's disease pathology in the living brain. Here we describe the synthesis of two meta-substituted chlorodifluoroacetophenones using a Weinreb amide strategy and their rapid conversion to the corresponding trifluoro derivatives through nucleophilic substitution by fluoride ion, in a reaction amenable to incorporating 18 F for PET imaging. In vitro kinetic analysis indicates tight binding of the trifluoro derivatives to cholinesterases. Compound 1 has a K i value of 7nM for acetylcholinesterase and 1300nM for butyrylcholinesterase while for compound 2 these values are 0.4nM and 26nM, respectively. Tight binding of these compounds to cholinesterase encourages their development for PET imaging detection of cholinesterase associated with Alzheimer's disease pathology. Copyright © 2016 Elsevier Ltd. All rights reserved.

Prospective neurobiological effects of the aerial and root extracts and some pure compounds of randomly selected Scorzonera species.

PubMed

Senol, F Sezer; Acikara, Ozlem Bahadir; Citoglu, Gulcin Saltan; Orhan, Ilkay Erdogan; Dall' Acqua, Stefano; Ozgökce, Fevzi

2014-07-01

Scorzonera L. species (Asteraceae) are edible and as medicinal plants are used for various purposed in folk medicine. The methanol extracts of the aerial parts and roots from 27 Scorzonera taxa were investigated for their possible neurobiological effects. Inhibitory potential of the Scorzonera species was tested against acetylcholinesterase (AChE), butyrylcholinesterase (BChE), and tyrosinase (TYRO) at 100 µg mL(-1) using ELISA microtiter assay. Antioxidant activity of the extracts was tested with radical scavenging activity, metal-chelation capacity, ferric- (FRAP), and phosphomolibdenum-reducing antioxidant power (PRAP) assays. Chlorogenic acid, hyperoside, rutin, and scorzotomentosin-4-O-β-glucoside were also screened in the same manner. Total phenol and flavonoid quantification in the extracts were determined spectrophotometrically. The aerial parts of Scorzonera pisidica (40.25 ± 0.74%) and chlorogenic acid (46.97 ± 0.82%) displayed the highest TYRO inhibition, while the remaining samples showed only trivial inhibition against cholinesterases (2.08 ± 1.35%-25.32 ± 1.37%). The same extract of S. pisidica was revealed to be the most potent in scavenging of all three radicals and FRAP assay. Out of 27 taxa, S. pisidica, in particular, may deserve further investigation for its neuroprotective potential.

Effect of BCHE single nucleotide polymorphisms on lipid metabolism markers in women.

PubMed

Oliveira, Jéssica de; Tureck, Luciane Viater; Santos, Willian Dos; Saliba, Louise Farah; Schenknecht, Caroline Schovanz; Scaraboto, Débora; Souza, Ricardo Lehtonen R; Furtado-Alle, Lupe

2017-01-01

Butyrylcholinesterase (BChE) activity and polymorphisms in its encoding gene had previously been associated with metabolic traits of obesity. This study investigated the association of three single nucleotide polymorphisms (SNPs) in the BCHE gene: -116G > A (rs1126680), 1615GA (rs1803274), 1914A < G (rs3495), with obesity and lipid metabolism markers, body mass index (BMI), total cholesterol (TC), low density lipoprotein cholesterol (LDL-C), high density lipoprotein cholesterol (HDL-C), triglyceride (TG) levels, and BChE enzymatic activity in obese (BMI≥30/n = 226) and non-obese women (BMI < 25/n = 81). BCHE SNPs genotyping was obtained by TaqMan allelic discrimination assay and by RFLP-PCR. Plasmatic BChE activity was measured using propionylthiocholine as substrate. Similar allele frequencies were found in obese and non-obese women for the three studied SNPs (p > 0.05). The dominant and recessive models were tested, and different effects were found. The -116A allele showed a dominant effect in BChE activity reduction in both non-obese and obese women (p = 0.045 and p < 0.001, respectively). The 1914A > G and 1615GA SNPs influenced the TG levels only in obese women. The 1914G and the 1615A alleles were associated with decreased plasma levels of TG. Thus, our results suggest that the obesity condition, characterized by loss of energy homeostasis, is modulated by BCHE polymorphisms.

Design, synthesis and biological evaluation of 3,4-dihydro-2(1H)-quinoline-O-alkylamine derivatives as new multipotent cholinesterase/monoamine oxidase inhibitors for the treatment of Alzheimer's disease.

PubMed

Sang, Zhipei; Pan, Wanli; Wang, Keren; Ma, Qinge; Yu, Lintao; Liu, Wenmin

2017-06-15

A new family of multitarget molecules able to interact with acetylcholinesterase (AChE) and butyrylcholinesterase (BuChE), as well as with monoamino oxidase (MAO) A and B, has been synthesized. Novel 3,4-dihydro-2(1H)-quinoline-O-alkylamine derivatives have been designed using a conjunctive approach that combines the JMC49 and donepezil. The most promising compound TM-33 showed potent and balance inhibitory activities toward ChE and MAO (eeAChE, eqBuChE, hMAO-A and hMAO-B with IC 50 values of 0.56μM, 2.3μM, 0.3μM and 1.4μM, respectively) but low selectivity. Both kinetic analysis of AChE inhibition and molecular modeling study suggested that TM-33 binds simultaneously to the catalytic active site and peripheral anionic site of AChE. Furthermore, our investigation proved that TM-33 could cross the blood-brain barrier (BBB) in vitro, and abided by Lipinski's rule of five. The results suggest that compound TM-33, an interesting multi-targeted active molecule, offers an attractive starting point for further lead optimization in the drug-discovery process against Alzheimer's disease. Copyright © 2017 Elsevier Ltd. All rights reserved.

Protective propensity of bacoside A and bromelain on renal cholinesterases, γ-Aminobutyric acid and serotonin level of Mus musculus intoxicated with dichlorvos.

PubMed

Agarwal, Sonam; Chaudhary, Bharti; Bist, Renu

2017-01-05

Current study established a protective action of bacoside A and bromelain against the toxic effects of dichlorvos in kidneys of mice. Experimental design included five groups. The first group was control. Mice of groups II, III and IV were administered doses of dichlorvos, bromelain and bacoside A respectively. In group V, mice were treated with both the antioxidants (bacoside A and bromelain) and dichlorvos. After 21 days of exposure of different doses, levels of acetylcholinesterase (AChE), butyrylcholinesterase (BChE), γ-aminobutyric acid (GABA) and serotonin were measured in renal tissues. Dichlorvos significantly reduced the kidney AChE (p < 0.001), BChE (p < 0.01) and GABA level (p < 0.01) compared to control. A simultaneous significant elevation in the serotonin level (p < 0.01) was recorded after dichlorvos exposure. Concomitant exposure of bacoside A and bromelain followed by dichlorvos treatment in group V not only restored, but increased the renal cholinesterases and GABA level. Meanwhile, a significant decline in serotonin level (p < 0.001) was revealed, compared to dichlorvos exposed mice. Bacoside A and bromelain occupy a tremendous antioxidant action in the mice kidneys and a combination of the same ameliorates the renal toxicity induced by dichlorvos. Copyright © 2016 Elsevier Ireland Ltd. All rights reserved.

Anti-Alzheimer's disease activity of compounds from the root bark of Morus alba L.

PubMed

Kuk, Eun Bi; Jo, A Ra; Oh, Seo In; Sohn, Hee Sook; Seong, Su Hui; Roy, Anupom; Choi, Jae Sue; Jung, Hyun Ah

2017-03-01

The inhibition of acetylcholinesterase (AChE), butyrylcholinesterase (BChE), and β-site amyloid precursor protein cleaving enzyme 1 (BACE1) plays important roles in prevention and treatment of Alzheimer's disease (AD). Among the individual parts of Morus alba L. including root bark, branches, leaves, and fruits, the root bark showed the most potent enzyme inhibitory activities. Therefore, the aim of this study was to evaluate the anti-AD activity of the M. alba root bark and its isolate compounds, including mulberrofuran G (1), albanol B (2), and kuwanon G (3) via inhibition of AChE, BChE, and BACE1. Compounds 1 and 2 showed strong AChE- and BChE-inhibitory activities; 1-3 showed significant BACE1 inhibitory activity. Based on the kinetic study with AChE and BChE, 2 and 3 showed noncompetitive-type inhibition; 1 showed mixed-type inhibition. Moreover, 1-3 showed mixed-type inhibition against BACE1. The molecular docking simulations of 1-3 demonstrated negative binding energies, indicating a high affinity to AChE and BACE1. The hydroxyl group of 1-3 formed hydrogen bond with the amino acid residues located at AChE and BACE1. Consequently, these results indicate that the root bark of M. alba and its active compounds might be promising candidates for preventive and therapeutic agents for AD.

Evaluation of the neuroprotective and antidiabetic potential of phenol-rich extracts from virgin olive oils by in vitro assays.

PubMed

Figueiredo-González, M; Reboredo-Rodríguez, P; González-Barreiro, C; Simal-Gándara, J; Valentão, P; Carrasco-Pancorbo, A; Andrade, P B; Cancho-Grande, B

2018-04-01

In this work, phenol-rich extracts from 'Cornicabra' and 'Picual' virgin-olive oils (EVOOs) were examined, for the first time, to establish their capacity to inhibit key enzymes involved in Alzheimer's disease (AD) (acetylcholinesterase (AChE), butyrylcholinesterase (BuChE) and 5-lipoxygenase (LOX)), major depressive disorder (MDD) and Parkinson's disease (PD) (monoamine oxidases: hMAO-A and hMAO-B respectively), and diabetes mellitus (DM) (α-glucosidase and α-amylase). 'Cornicabra' displayed the best inhibitory activity against all enzymes, when compared to 'Picual': BuChE (IC 50  = 156 ± 4 and 308 ± 33 mg mL -1 ), LOX (IC 50  = 26 ± 0.5 and 37 ± 3 mg mL -1 ), hMAO-A (IC 50  = 20 ± 2 and 37 ± 0.2 mg mL -1 ), hMAO-B (IC 50  = 131 ± 7 and 215 ± 13 mg mL -1 ) and α-glucosidase (IC 50  = 154 ± 17 and 251 ± 31 mg mL -1 ), respectively. The behaviour observed can be associated with the higher content of secoiridoids, lignans and phenolic acids in 'Cornicabra' EVOO. Copyright © 2018 Elsevier Ltd. All rights reserved.

Nutraceutical Potential of Phenolics from 'Brava' and 'Mansa' Extra-Virgin Olive Oils on the Inhibition of Enzymes Associated to Neurodegenerative Disorders in Comparison with Those of 'Picual' and 'Cornicabra'.

PubMed

Figueiredo-González, María; Reboredo-Rodríguez, Patricia; González-Barreiro, Carmen; Carrasco-Pancorbo, Alegría; Simal-Gándara, Jesús; Cancho-Grande, Beatriz

2018-03-21

The increasing interest in the Mediterranean diet is based on the protective effects against several diseases, including neurodegenerative disorders. Polyphenol-rich functional foods have been proposed to be unique supplementary and nutraceutical treatments for these disorders. Extra-virgin olive oils (EVOOs) obtained from 'Brava' and 'Mansa', varieties recently identified from Galicia (northwestern Spain), were selected for in vitro screening to evaluate their capacity to inhibit key enzymes involved in Alzheimer's disease (AD) (acetylcholinesterase (AChE), butyrylcholinesterase (BuChE) and 5-lipoxygenase (5-LOX)), major depressive disorder (MDD) and Parkinson's disease (PD) (monoamine oxidases: h MAO-A and h MAO-B respectively). 'Brava' oil exhibited the best inhibitory activity against all enzymes, when they are compared to 'Mansa' oil: BuChE (IC 50 = 245 ± 5 and 591 ± 23 mg·mL -1 ), 5-LOX (IC 50 = 45 ± 7 and 106 ± 14 mg·mL -1 ), h MAO-A (IC 50 = 30 ± 1 and 72 ± 10 mg·mL -1 ) and h MAO-B (IC 50 = 191 ± 8 and 208 ± 14 mg·mL -1 ), respectively. The inhibitory capacity of the phenolic extracts could be associated with the content of secoiridoids, lignans and phenolic acids.

In Silico Identification and Experimental Validation of Novel Anti-Alzheimer's Multitargeted Ligands from a Marine Source Featuring a "2-Aminoimidazole plus Aromatic Group" Scaffold.

PubMed

Vitale, Rosa Maria; Rispoli, Vincenzo; Desiderio, Doriana; Sgammato, Roberta; Thellung, Stefano; Canale, Claudio; Vassalli, Massimo; Carbone, Marianna; Ciavatta, Maria Letizia; Mollo, Ernesto; Felicità, Vera; Arcone, Rosaria; Gavagnin Capoggiani, Margherita; Masullo, Mariorosario; Florio, Tullio; Amodeo, Pietro

2018-03-07

Multitargeting or polypharmacological approaches, looking for single chemical entities retaining the ability to bind two or more molecular targets, are a potentially powerful strategy to fight complex, multifactorial pathologies. Unfortunately, the search for multiligand agents is challenging because only a small subset of molecules contained in molecular databases are bioactive and even fewer are active on a preselected set of multiple targets. However, collections of natural compounds feature a significantly higher fraction of bioactive molecules than synthetic ones. In this view, we searched our library of 1175 natural compounds from marine sources for molecules including a 2-aminoimidazole+aromatic group motif, found in known compounds active on single relevant targets for Alzheimer's disease (AD). This identified two molecules, a pseudozoanthoxanthin (1) and a bromo-pyrrole alkaloid (2), which were predicted by a computational approach to possess interesting multitarget profiles on AD target proteins. Biochemical assays experimentally confirmed their biological activities. The two compounds inhibit acetylcholinesterase, butyrylcholinesterase, and β-secretase enzymes in high- to sub-micromolar range. They are also able to prevent and revert β-amyloid (Aβ) aggregation of both Aβ 1-40 and Aβ 1-42 peptides, with 1 being more active than 2. Preliminary in vivo studies suggest that compound 1 is able to restore cholinergic cortico-hippocampal functional connectivity.

Synthesis, spectral characterization and computed optical analysis of potent triazole based compounds

NASA Astrophysics Data System (ADS)

Sumrra, Sajjad H.; Mushtaq, Fazila; Khalid, Muhammad; Raza, Muhammad Asam; Nazar, Muhammad Faizan; Ali, Bakhat; Braga, Ataualpa A. C.

2018-02-01

Biologically active triazole Schiff base ligand (L) and metal complexes [Fe(II), Co(II), Ni(II), Cu(II) and Zn(II)] are reported herein. The ligand acted as tridentate and coordinated towards metallic ions via azomethine-N, triazolic-N moiety and deprotonated-O of phenyl substituents in an octahedral manner. These compounds were characterized by physical, spectral and analytical analysis. The synthesized ligand and metal complexes were screened for antibacterial pathogens against Chromohalobacter salexigens, Chromohalobacter israelensi, Halomonas halofila and Halomonas salina, antifungal bioassay against Aspergillus niger and Aspergellus flavin, antioxidant (DPPH, phosphomolybdate) and also for enzyme inhibition [butyrylcholinesterase (BChE) and acetylcholinesterase (AChE)] studies. The results of these activities indicated the ligand to possess potential activity which significantly increased upon chelation. Moreover, vibrational bands, frontier molecular orbitals (FMOs) and natural bond analysis (NBO) of ligand (1) were carried out through density functional theory (DFT) with B3lYP/6-311 ++G (d,p) approach. While, UV-Vis analysis was performed by time dependent TD-DFT with B3lYP/6-311 ++G (d,p) method. NBO analysis revealed that investigated compound (L) contains enormous molecular stability owing to hyper conjugative interactions. Theoretical spectroscopic findings showed good agreement to experimental spectroscopic data. Global reactivity descriptors were calculated using the energies of FMOs which indicated compound (L) might be bioactive. These parameters confirmed the charge transfer phenomenon and reasonable correspondence with experimental bioactivity results.

Effects of sublethal fenitrothion ingestion on cholinesterase inhibition, standard metabolism, thermal preference, and prey-capture ability in the Australian central bearded dragon (Pogona vitticeps, Agamidae).

PubMed

Bain, David; Buttemer, William A; Astheimer, Lee; Fildes, Karen; Hooper, Michael J

2004-01-01

The central bearded dragon (Pogona vitticeps) is a medium-sized lizard that is common in semiarid habitats in Australia and that potentially is at risk of fenitrothion exposure from use of the chemical in plague locust control. We examined the effects of single sublethal doses of this organophosphate (OP; low dose = 2.0 mg/kg; high dose = 20 mg/kg; control = vehicle alone) on lizard thermal preference, standard metabolic rate, and prey-capture ability. We also measured activities of plasma total cholinesterase (ChE) and acetylcholinesterase before and at 0, 2, 8, 24, 120, and 504 h after OP dosing. Predose plasma total ChE activity differed significantly between sexes and averaged 0.66 +/- 0.06 and 0.45 +/- 0.06 micromol/min/ml for males and females, respectively. Approximately 75% of total ChE activity was attributable to butyrylcholinesterase. Peak ChE inhibition reached 19% 2 h after OP ingestion in the low-dose group, and 68% 8 h after ingestion in high-dose animals. Neither OP doses significantly affected diurnal body temperature, standard metabolic rate, or feeding rate. Plasma total ChE levels remained substantially depressed up to 21 d after dosing in the high-dose group, making this species a useful long-term biomonitor of OP exposure in its habitat.

Biological Activities and Chemical Composition of Methanolic Extracts of Selected Autochthonous Microalgae Strains from the Red Sea.

PubMed

Pereira, Hugo; Custódio, Luísa; Rodrigues, Maria João; de Sousa, Carolina Bruno; Oliveira, Marta; Barreira, Luísa; Neng, Nuno da Rosa; Nogueira, José Manuel Florêncio; Alrokayan, Salman A; Mouffouk, Fouzi; Abu-Salah, Khalid M; Ben-Hamadou, Radhouan; Varela, João

2015-06-03

Four lipid-rich microalgal species from the Red Sea belonging to three different genera (Nannochloris, Picochlorum and Desmochloris), previously isolated as novel biodiesel feedstocks, were bioprospected for high-value, bioactive molecules. Methanol extracts were thus prepared from freeze-dried biomass and screened for different biological activities. Nannochloris sp. SBL1 and Desmochloris sp. SBL3 had the highest radical scavenging activity against 1,1-diphenyl-2-picrylhydrazyl, and the best copper and iron chelating activities. All species had potent butyrylcholinesterase inhibitory activity (>50%) and mildly inhibited tyrosinase. Picochlorum sp. SBL2 and Nannochloris sp. SBL4 extracts significantly reduced the viability of tumoral (HepG2 and HeLa) cells with lower toxicity against the non-tumoral murine stromal (S17) cells. Nannochloris sp. SBL1 significantly reduced the viability of Leishmania infantum down to 62% (250 µg/mL). Picochlorum sp. SBL2 had the highest total phenolic content, the major phenolic compounds identified being salicylic, coumaric and gallic acids. Neoxanthin, violaxanthin, zeaxanthin, lutein and β-carotene were identified in the extracts of all strains, while canthaxanthin was only identified in Picochlorum sp. SBL2. Taken together, these results strongly suggest that the microalgae included in this work could be used as sources of added-value products that could be used to upgrade the final biomass value.

Biological Activities and Chemical Composition of Methanolic Extracts of Selected Autochthonous Microalgae Strains from the Red Sea

PubMed Central

Pereira, Hugo; Custódio, Luísa; Rodrigues, Maria João; Bruno de Sousa, Carolina; Oliveira, Marta; Barreira, Luísa; Neng, Nuno da Rosa; Nogueira, José Manuel Florêncio; Alrokayan, Salman A.; Mouffouk, Fouzi; Abu-Salah, Khalid M.; Ben-Hamadou, Radhouan; Varela, João

2015-01-01

Four lipid-rich microalgal species from the Red Sea belonging to three different genera (Nannochloris, Picochlorum and Desmochloris), previously isolated as novel biodiesel feedstocks, were bioprospected for high-value, bioactive molecules. Methanol extracts were thus prepared from freeze-dried biomass and screened for different biological activities. Nannochloris sp. SBL1 and Desmochloris sp. SBL3 had the highest radical scavenging activity against 1,1-diphenyl-2-picrylhydrazyl, and the best copper and iron chelating activities. All species had potent butyrylcholinesterase inhibitory activity (>50%) and mildly inhibited tyrosinase. Picochlorum sp. SBL2 and Nannochloris sp. SBL4 extracts significantly reduced the viability of tumoral (HepG2 and HeLa) cells with lower toxicity against the non-tumoral murine stromal (S17) cells. Nannochloris sp. SBL1 significantly reduced the viability of Leishmania infantum down to 62% (250 µg/mL). Picochlorum sp. SBL2 had the highest total phenolic content, the major phenolic compounds identified being salicylic, coumaric and gallic acids. Neoxanthin, violaxanthin, zeaxanthin, lutein and β-carotene were identified in the extracts of all strains, while canthaxanthin was only identified in Picochlorum sp. SBL2. Taken together, these results strongly suggest that the microalgae included in this work could be used as sources of added-value products that could be used to upgrade the final biomass value. PMID:26047482

Chemistry and functional properties in prevention of neurodegenerative disorders of five Cistus species essential oils.

PubMed

Loizzo, Monica Rosa; Ben Jemia, Mariem; Senatore, Felice; Bruno, Maurizio; Menichini, Francesco; Tundis, Rosa

2013-09-01

The chemical composition of Cistus creticus, Cistus salvifolius, Cistus libanotis, Cistus monspeliensis and Cistus villosus essential oils has been examined by GC and GC-MS analysis. Height-nine constituents were identified in C. salvifolius oil, sixty in C. creticus, fifty-six in C. libanotis, fifty-four in C. villosus, forty-five in C. monspeliensis. Although the five species belong to the same genus, the composition showed interesting differences. Essential oils were screened also for their potential antioxidant effects (by DPPH, ABTS, FRAP and β-carotene bleaching test) and their acetylcholinesterase (AChE) and butyrylcholinesterase (BChE) inhibitory activity, useful for prevention and treatment of Alzheimer's disease. C. monspeliensis exhibited the most promising activity in β-carotene bleaching test (IC₅₀ of 54.7 μg/mL). In FRAP test C. libanotis showed a value of 19.2 μM Fe(II)/g. C. salvifolius showed the highest activity against AChE (IC₅₀ of 58.1 μg/mL) while C. libanotis, C. creticus, C. salvifolius demonstrated a good inhibitory activity against BChE with IC₅₀ values of 23.7, 29.1 and 34.2 μg/mL, respectively. Overall our results could promote the use of the essential oil of different Cistus species as food additives and for formulation of herbal infusion or nutraceutical products. Copyright © 2013 Elsevier Ltd. All rights reserved.

Cholinesterase activities and behavioral changes in Hypsiboas pulchellus (Anura: Hylidae) tadpoles exposed to glufosinate ammonium herbicide.

PubMed

Peltzer, Paola M; Junges, Celina M; Attademo, Andrés M; Bassó, Agustín; Grenón, Paula; Lajmanovich, Rafael C

2013-09-01

In this study, amphibian tadpoles of Hypsiboas pulchellus were exposed to herbicide Liberty®, which contains glufosinate ammonium (GLA), for 48 h to the following concentrations: 0 (control), 3.55, 4.74, 6.32, 8.43, 11.25, 15, 20, 26.6, and 35.5 mg GLA L(-1). Acetylcholinesterase (AChE) and butyrylcholinesterase (BChE) activities, as well as swimming capabilities (swimming speed and mean distance) were measured in tadpoles whose concentrations displayed survival rates > 85 %. Our results reveal that sublethal concentrations of GLA significantly inhibited both AChE and BChE activities in tadpoles with respect to the control, showing a concentration-dependent inhibitory effect. The highest inhibition percentages of AChE (50.86%) and BChE (53.02%) were registered in tadpoles exposed to 15 mg GLA L(-1). At this concentration, a significant increase of the swimming speed and mean distance were found in exposed tadpoles with respect to the control, as well as a negative and significant correlation between swimming speed and BChE activity, thus suggesting that this enzyme inhibition is related to an increase in swimming speed. Therefore, exposure of tadpoles to GLA in the wild at concentrations similar to those tested here may have adverse consequences at population level because neurotransmission and swimming performance are essential for tadpole performance and survival.

Neurologically Potent Molecules from Crataegus oxyacantha; Isolation, Anticholinesterase Inhibition, and Molecular Docking

PubMed Central

Ali, Mumtaz; Muhammad, Sultan; Shah, Muhammad R.; Khan, Ajmal; Rashid, Umer; Farooq, Umar; Ullah, Farhat; Sadiq, Abdul; Ayaz, Muhammad; Ali, Majid; Ahmad, Manzoor; Latif, Abdul

2017-01-01

Crataegus oxyacantha is an important herbal supplement and famous for its antioxidant potential. The antioxidant in combination with anticholinesterase activity can be considered as an important target in the management of Alzheimer’s disease. The compounds isolated from C. oxyacantha were evaluated for cholinesterases inhibitory activity using Ellman’s assay with Galantamine as standard drug. Total of nine (1–9) compounds were isolated. Compounds 1 and 2 were isolated for the first time from natural source. Important natural products like β-Sitosterol-3-O-β-D-Glucopyranoside (3), lupeol (4), β-sitosterol (5), betulin (6), betulinic acid (7), oleanolic acid (8), and chrysin (9) have also been isolated from C. oxyacantha. Overall, all the compounds exhibited an overwhelming acetylcholinesterase (AChE) inhibition potential in the range 5.22–44.47 μM. The compound 3 was prominent AChE inhibitor with IC50 value of 5.22 μM. Likewise, all the compounds were also potent in butyrylcholinesterase (BChE) inhibitions with IC50s of up to 0.55–15.36 μM. All the compounds, except 3, were selective toward BChE. Mechanism of the inhibition of both the enzymes were further studied by docking procedures using Genetic Optimization for Ligand Docking suit v5.4.1. Furthermore, computational blood brain barrier prediction of the isolated compounds suggest that these are BBB+. PMID:28638340

In Vitro Screening of Three Indian Medicinal Plants for Their Phytochemicals, Anticholinesterase, Antiglucosidase, Antioxidant, and Neuroprotective Effects

PubMed Central

Penumala, Mohan; Zinka, Raveendra Babu; Shaik, Jeelan Basha

2017-01-01

Cooccurrence of Diabetes Mellitus and Alzheimer's disease in elder people prompts scientists to develop multitarget agents that combat causes and symptoms of both diseases simultaneously. In line with this modern paradigm and as a follow-up to our previous studies, the present study is designed to investigate the crude methanolic extracts and subsequent CHCl3, n-BuOH, and H2O fractions of Acalypha alnifolia, Pavetta indica, and Ochna obtusata for their inhibitory activities towards specific targets involved in AD and DM, namely, acetylcholinesterase, butyrylcholinesterase, and α-glucosidase (α-Glc). The methanolic extract and its derived chloroform fractions exhibited remarkable inhibitory capacities with IC50 values being found at the μg/mL level. Further studies on most active chloroform fractions presented a prominent ability to scavenge DPPH and ABTS reactive species and highest neuroprotective effect against H2O2 induced cell injury. Phytochemical analysis showed a large amount of phenolics, flavonoids, and terpenoids in active fractions. In conclusion, A. alnifolia, P. indica, and O. obtusata could be promising sources for the treatment of AD and DM since these fractions induced significant anticholinesterase, antidiabetic, antioxidant, and neuroprotection effects attributable to phenolic, flavonoid, and terpenoid contents and encourage further studies for development of multifunctional therapeutic agent for AD and DM dual therapy. PMID:29204442

Biomarkers of Sensitivity and Exposure in Washington State Pesticide Handlers

PubMed Central

Keifer, M.C.; Checkoway, H.; De Roos, A.J.; Farin, F.M.; Fenske, R.A.; Richter, R.J.; van Belle, G.; Furlong, C.E.

2011-01-01

Organophosphate (OP) and N-methyl-carbamate (CB) insecticides are widely used in agriculture in the US and abroad. These compounds – which inhibit acetylcholinesterase (AChE) enzyme activity – continue to be responsible for a high proportion of pesticide poisonings among US agricultural workers. It is possible that some individuals may be especially susceptible to health effects related to OP/CB exposure. The paraoxonase (PON1) enzyme metabolizes the highly toxic oxon forms of some OPs, and an individual's PON1 status may be an important determinant of his or her sensitivity to these chemicals. This chapter discusses methods used to characterize individual PON1 status and reviews previous epidemiologic studies that have evaluated PON1-related sensitivity to OPs in relation to various health endpoints. It also describes an ongoing longitudinal study among OP-exposed agricultural pesticide handlers who are participating in a recently implemented cholinesterase monitoring program in Washington State. This study will evaluate handlers' PON1 status as a hypothesized determinant of butyrylcholinesterase (BuChE) inhibition. Such studies will be useful to determine how regulatory risk assessments might account for differences in PON1-related OP sensitivity when characterizing inter-individual variability in risk related to OP exposure. Recent work assessing newer and more sensitive biomarkers of OP exposure is also discussed briefly in this chapter. PMID:20221867

Postnatal chlorpyrifos exposure and apolipoprotein E (APOE) genotype differentially affect cholinergic expression and developmental parameters in transgenic mice.

PubMed

Basaure, Pia; Guardia-Escote, Laia; Cabré, Maria; Peris-Sampedro, Fiona; Sánchez-Santed, Fernando; Domingo, José L; Colomina, Maria Teresa

2018-05-03

Chlorpyrifos (CPF) is one of the most commonly used organophosphate pesticides in the world. Our previous results described that apolipoprotein E (APOE) polymorphisms are a source of individual differences in susceptibility to CPF. The aim of this study was to assess the physical and biochemical effects of postnatal exposure to CPF in the apoE targeted replacement mouse model. Mice were exposed to CPF at 0 or 1 mg/kg/day from postnatal day 10-15. Physical development, plasma and forebrain cholinesterase (ChE) activity and gene expression in liver and forebrain were evaluated. CPF exposure delays physical maturation and decreases the expression of choline acetyltransferase, α4-subunit and the α7 receptor. CPF decreases the expression of vesicular acetylcholine transporter (VAChT) mRNA in the forebrain only in apoE3 mice. The expression of paraoxonase-2 in the forebrain was also influenced by APOE genotype and CPF. Differences between genotypes were observed in litter size, ChE activity, expression of butyrylcholinesterase and paraoxonase-1 in liver and variants of acetylcholinesterase, VAChT and the α7 receptor in the forebrain. These results support that there are different vulnerabilities to postnatal CPF exposure according to the APOE polymorphism, which in turn affects the cholinergic system and defenses to oxidative stress. Copyright © 2018 Elsevier Ltd. All rights reserved.

2-Arylbenzofurans from Artocarpus lakoocha and methyl ether analogs with potent cholinesterase inhibitory activity.

PubMed

Namdaung, Umalee; Athipornchai, Anan; Khammee, Thongchai; Kuno, Mayuso; Suksamrarn, Sunit

2018-01-01

In vitro screening for acetylcholinesterase (AChE) and butyrylcholinesterase (BChE) inhibitory activities of the Artocarpus lakoocha root-bark extracts revealed interesting results. Bioassay-guided fractionation resulted in the isolation of two new (1 and 2) and six known 2-arylbenzofurans 3-8, along with one stilbenoid 9 and one flavonoid 10. The structures of the isolated compounds were elucidated by UV, IR, 1D- and 2D-NMR and MS spectroscopic data analysis. Compounds 4, 6 and 7 exhibited more potent AChE inhibitory activity (IC 50  = 0.87-1.10 μM) than the reference drug, galantamine. Compounds 4, 8 and 9 displayed greater BChE inhibition than the standard drug. The preferential inhibition of BChE over AChE indicated that 4 also showed a promising dual AChE and BChE inhibitor. The synthetic mono-methylated analogs 4a-c and 6a-b were found to be good BChE inhibitors with IC 50 values ranging between 0.31 and 1.11 μM. Based on the docking studies, compounds 4 and 6 are well-fitted in the catalytic triad of AChE. Compounds 4 and 6 showed different binding orientations on BChE, and the most potent BChE inhibitor 4 occupied dual binding to both CAS and PAS more efficiently. Copyright © 2017 Elsevier Masson SAS. All rights reserved.

Synthesis and in vitro evaluation of novel rhodanine derivatives as potential cholinesterase inhibitors.

PubMed

Krátký, Martin; Štěpánková, Šárka; Vorčáková, Katarína; Vinšová, Jarmila

2016-10-01

Based on a broad spectrum of biological activities of rhodanines, we synthesized aromatic amides and esters of 2-(4-oxo-2-thioxothiazolidin-3-yl)acetic acid (rhodanine-3-acetic acid) via carbodiimide- or PCl3-mediated coupling. Both esters and amides were investigated for their in vitro inhibitory potency and selectivity against acetylcholinesterase (AChE) from electric eel and butyrylcholinesterase (BChE) from equine serum using Ellman's spectrophotometric method. The derivatives exhibited mostly a moderate activity against both cholinesterases. IC50 values for AChE were in a closer concentration range of 24.05-86.85μM when compared to BChE inhibition (7.92-227.19μM). The esters caused the more efficient inhibition of AChE than amides and parent acid. The esterification and amidation of the rhodanine-3-acetic acid increased inhibition of BChE, even up to 26 times. Derivatives of 4-nitroaniline/phenol showed the activity superior to other substituents (H, Cl, CH3, OCH3, CF3). Rhodanines produced a balanced inhibition of both cholinesterases. Seven derivatives produced the more potent inhibition of AChE than rivastigmine, a clinically used drug; additional three compounds were comparable. Two amides exceeded inhibitory potency of rivastigmine towards BChE. Importantly, this is the first evidence that rhodanine-based compounds are able to inhibit BChE. Copyright © 2016 Elsevier Inc. All rights reserved.

Synthesis and biological evaluation of a series of dithiocarbamates as new cholinesterase inhibitors.

PubMed

Altıntop, Mehlika D; Gurkan-Alp, A Selen; Ozkay, Yusuf; Kaplancıklı, Zafer A

2013-08-01

In the present paper, a novel series of dithiocarbamates was synthesized via the treatment of 4-(trifluoromethyl)benzyl chloride with appropriate sodium salts of N,N-disubstituted dithiocarbamic acids. The chemical structures of the compounds were elucidated by (1) H NMR, mass spectral data, and elemental analyses. Each derivative was evaluated for its ability to inhibit acetylcholinesterase (AChE) and butyrylcholinesterase (BuChE) using a modification of Ellman's spectrophotometric method. The most potent AChE inhibitor was found as compound 2g (IC50  = 0.53 ± 0.001 µM) followed by compounds 2f (IC50  = 0.74 ± 0.001 µM) and 2j (IC50  = 0.89 ± 0.002 µM) when compared with donepezil (IC50  = 0.048 ± 0.001 µM). Compounds 2f and 2g were more effective than donepezil (IC50  = 7.88 ± 0.52 µM) on BuChE inhibition. Compounds 2f and 2g exhibited the inhibitory effect on BuChE with IC50 values of 1.39 ± 0.041 and 3.64 ± 0.072 µM, respectively. © 2013 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

New cholinesterase inhibitors for Alzheimer's disease: Structure Activity Studies (SARs) and molecular docking of isoquinolone and azepanone derivatives.

PubMed

Bacalhau, Patrícia; San Juan, Amor A; Marques, Carolina S; Peixoto, Daniela; Goth, Albertino; Guarda, Cátia; Silva, Mara; Arantes, Sílvia; Caldeira, A Teresa; Martins, Rosário; Burke, Anthony J

2016-08-01

A library of isoquinolinone and azepanone derivatives were screened for both acetylcholinesterase (AChE) and butyrylcholinesterase (BuChE) activity. The strategy adopted included (a) in vitro biological assays, against eel AChE (EeAChE) and equine serum BuChE (EqBuChE) in order to determine the compounds IC50 and their dose-response activity, consolidated by (b) molecular docking studies to evaluate the docking poses and interatomic interactions in the case of the hit compounds, validated by STD-NMR studies. Compound (1f) was identified as one of these hits with an IC50 of 89.5μM for EeAChE and 153.8μM for EqBuChE, (2a) was identified as a second hit with an IC50 of 108.4μM (EeAChE) and 277.8μM (EqBuChE). In order to gain insights into the binding mode and principle active site interactions of these molecules, (R)-(1f) along with 3 other analogues (also as the R-enantiomer) were docked into both RhAChE and hBuChE models. Galantamine was used as the benchmark. The docking study was validated by performing an STD-NMR study of (1f) with EeAChE using galantamine as the benchmark. Copyright © 2016 Elsevier Inc. All rights reserved.

Alkaloids as a source of potential anticholinesterase inhibitors for the treatment of Alzheimer's disease.

PubMed

Konrath, Eduardo Luis; Passos, Carolina dos Santos; Klein, Luiz Carlos; Henriques, Amélia T

2013-12-01

The inhibition of acetylcholinesterase (AChE), the key enzyme in the breakdown of acetylcholine, is currently the main pharmacological strategy available for Alzheimer's disease (AD). In this sense, many alkaloids isolated from natural sources, such as physostigmine, have been long recognized as acetyl- and butyrylcholinesterase (BChE) inhibitors. Since the approval of galantamine for the treatment of AD patients, the search for new anticholinesterase alkaloids has escalated, leading to promising candidates such as huperzine A. This review aims to summarize recent advances in current knowledge on alkaloids as AChE and BChE inhibitors, highlighting structure-activity relationship (SAR) and docking studies. Natural alkaloids belonging to the steroidal/triterpenoidal, quinolizidine, isoquinoline and indole classes, mainly distributed within Buxaceae, Amaryllidaceae and Lycopodiaceae, are considered important sources of alkaloids with anti-enzymatic properties. Investigations into the possible SARs for some active compounds are based on molecular modelling studies, predicting the mode of interaction of the molecules with amino acid residues in the active site of the enzymes. Following this view, an increasing interest in achieving more potent and effective analogues makes alkaloids good chemical templates for the development of new cholinesterase inhibitors. The anticholinesterase activity of alkaloids, together with their structural diversity and physicochemical properties, makes them good candidate agents for the treatment of AD. © 2013 Royal Pharmaceutical Society.

Potential anti-cholinesterase and β-site amyloid precursor protein cleaving enzyme 1 inhibitory activities of cornuside and gallotannins from Cornus officinalis fruits.

PubMed

Bhakta, Himanshu Kumar; Park, Chan Hum; Yokozawa, Takako; Tanaka, Takashi; Jung, Hyun Ah; Choi, Jae Sue

2017-07-01

Cholinesterase (ChE) and β-site amyloid precursor protein cleaving enzyme 1 (BACE1) inhibitors are promising agents for the treatment of Alzheimer's disease (AD). In the present study, we examined the inhibitory activity of seven compounds isolated from the fruits of Cornus officinalis, cornuside, polymeric proanthocyanidins, 1,2,3-tri-O-galloyl-β-D-glucose, 1,2,3,6-tetra-O-galloyl-β-D-glucose, tellimagrandin I, tellimagrandin II, and isoterchebin, against acetylcholinesterase (AChE), butyrylcholinesterase (BChE), and BACE1. All of the compounds displayed concentration-dependent in vitro inhibitory activity toward the ChEs and BACE1. Among them, tellimagrandin II exhibited the best inhibitory activity toward ChEs, whereas the best BACE1 inhibitor was 1,2,3,6-tetra-O-galloyl-β-D-glucose. Isoterchebin and polymeric proanthocyanidins were also significant ChE inhibitors. The kinetic and docking studies demonstrated that all compounds interacted with both the catalytic active sites and the peripheral anionic sites of the ChEs and BACE1. Tellimagrandin II, isoterchebin, and the polymeric proanthocyanidins exhibited concentration-dependent inhibition of peroxynitrite-mediated protein tyrosine nitration. In conclusion, we identified significant ChE and BACE1 inhibitors from Corni Fructus that could have value as new multi-targeted compounds for anti-AD agents.

In-silico identification of the binding mode of synthesized adamantyl derivatives inside cholinesterase enzymes

PubMed Central

Al-Aboudi, Amal; Al-Qawasmeh, Raed A; Shahwan, Alaa; Mahmood, Uzma; Khalid, Asaad; Ul-Haq, Zaheer

2015-01-01

Aim: To investigate the binding mode of synthesized adamantly derivatives inside of cholinesterase enzymes using molecular docking simulations. Methods: A series of hybrid compounds containing adamantane and hydrazide moieties was designed and synthesized. Their inhibitory activities against acetylcholinesterase (AChE) and (butyrylcholinesterase) BChE were assessed in vitro. The binding mode of the compounds inside cholinesterase enzymes was investigated using Surflex-Dock package of Sybyl7.3 software. Results: A total of 26 adamantyl derivatives were synthesized. Among them, adamantane-1-carboxylic acid hydrazide had an almost equal inhibitory activity towards both enzymes, whereas 10 other compounds exhibited moderate inhibitory activity against BChE. The molecular docking studies demonstrated that hydrophobic interactions between the compounds and their surrounding residues in the active site played predominant roles, while hydrophilic interactions were also found. When the compounds were docked inside each enzyme, they exhibited stronger interactions with BChE over AChE, possibly due to the larger active site of BChE. The binding affinities of the compounds for BChE and AChE estimated were in agreement with the experimental data. Conclusion: The new adamantly derivatives selectively inhibit BChE with respect to AChE, thus making them good candidates for testing the hypothesis that BChE inhibitors would be more efficient and better tolerated than AChE inhibitors in the treatment of Alzheimer's disease. PMID:25937631

Cholinesterase enzymes inhibitors from the leaves of Rauvolfia reflexa and their molecular docking study.

PubMed

Fadaeinasab, Mehran; Hadi, A Hamid A; Kia, Yalda; Basiri, Alireza; Murugaiyah, Vikneswaran

2013-03-25

Plants of the Apocynaceae family have been traditionally used in the treatment of age-related brain disorders. Rauvolfia reflexa, a member of the family, has been used as an antidote for poisons and to treat malaria. The dichloromethane, ethanol and methanol extracts from the leaves of Rauvolfia reflexa showed potential acetylcholinesterase (AChE) and butyrylcholinesterase (BChE) inhibitory activities, with IC50 values in the 8.49 to 52.23 g/mL range. Further cholinesterase inhibitory-guided isolation of these extracts afforded four bioactive compounds, namely: (E)-3-(3,4,5-trimethoxyphenyl)acrylic acid (1), (E)-methyl 3-(4-hydroxy-3,5-dimethoxyphenyl) acrylate (2), 17-methoxycarbonyl-14-heptadecaenyl-4-hydroxy-3-methoxycinnamate (3) and 1,2,3,4-tetrahydro-1-oxo-β-carboline (4). The isolated compounds showed moderate cholinesterase inhibitory activity compared to the reference standard, physostigmine. Compounds 1 and 2 showed the highest inhibitory activity against AChE (IC50 = 60.17 µM) and BChE (IC50 = 61.72 µM), respectively. Despite having similar molecular weight, compounds 1 and 2 were structurally different according to their chemical substitution patterns, leading to their different enzyme inhibition selectivity. Compound 2 was more selective against BChE, whereas compound 1 was a selective inhibitor of AChE. Molecular docking revealed that both compounds 1 and 2 were inserted, but not deeply into the active site of the cholinesterase enzymes.

Trafficking of cholinesterases and neuroligins mutant proteins. An association with autism.

PubMed

De Jaco, Antonella; Comoletti, Davide; King, Charles C; Taylor, Palmer

2008-09-25

Autism encompasses a wide spectrum of disorders arising during brain development. Recent studies reported that sequence polymorphisms in neuroligin-3 (NLGN3) and neuroligin-4 (NLGN4) genes have been linked to autism spectrum disorders indicating neuroligin genes as candidate targets in brain disorders. We have characterized a single mutation found in two affected brothers that substituted Arg451 to Cys in NL3. Our data show that the exposed Cys causes retention of the protein in the endoplasmic reticulum (ER) when expressed in HEK-293 cells. To examine whether the introduction of a Cys in the C-terminal region of other alpha/beta-hydrolase fold proteins could promote the same cellular phenotype, we made homologous mutations in acetylcholinesterase (AChE) and butyrylcholinesterase (BChE) and found a similar processing deficiency and intracellular retention (De Jaco et al., J Biol Chem. 2006, 281:9667-76). NL3, AChE and BChE mutant proteins are recognized as misfolded in the ER, and degraded via the proteasome pathway. A 2D electrophoresis coupled with mass spectrometry based approach was used to analyze proteins co-immunoprecipitating with NL3 and show differential expression of factors interacting with wild type and mutant NL3. We identified several proteins belonging to distinct ER resident chaperones families, including calnexin, responsible for playing a role in the folding steps of the AChE and NLs.

Neuroprotective Effects of Korean Red Pine(Pinus densiflora) Bark Extract and Its Phenolics.

PubMed

Kim, Ji-Won; Im, Sungbin; Jeong, Ha-Ram; Jung, Young-Seung; Lee, Inil; Kim, Kwan Joong; Park, Seung Kook; Kim, Dae-Ok

2018-03-15

Korean red pine ( Pinus densiflora ) is one of the major Pinus species in Korea. Red pine barkis removed prior to the chipping process in the wood industry and discarded aswaste. However, red pine bark contains a considerable amount of naturally occurring phenolics including flavonoids and therefore may have a variety of biological effects. In this study, we investigated if Korean red pine bark extract (KRPBE) could protect neuronal PC-12 cells from oxidative stress and inhibit cholinesterase activity.Analysis of reversed-phase high-performance liquid chromatography results revealed four phenolics in KRPBE:vanillin, protocatechuic acid, catechin and taxifolin.Total phenolic and flavonoid contents of KRPBE were 397.9 mg gallic acid equivalents/g dry weight (DW) and 248.7 mg catechin equivalents/g DW, respectively. Antioxidant capacities of KRPBE measured using ABTS, DPPH, and ORAC assays were 697.3, 521.8, and 2,627.7 mg vitamin C equivalents/g DW, respectively. KRPBE and its identified phenolics protected against H 2 O 2 -induced oxidative cell death in a dose-dependent manner. Acetylcholinesterase and butyrylcholinesterase, which degrade the neurotransmitter acetylcholine to terminate neurotransmission in synaptic clefts, were inhibited by treatment with KRPBE and its identified phenolics. Taken together, these results suggest that KRPBE and its constituent antioxidative phenolics are potent neuroprotective agents that can maintain cell viability in the context of oxidative stress and inhibit cholinesterase activity.

Association of Paraoxonase-1 Q192R (rs662) Single Nucleotide Variation with Cardiovascular Risk in Coffee Harvesters of Central Colombia

PubMed Central

Garzón-Castaño, Sandra; Ramos-Márquez, Martha E.; Hernández-Cañaveral, Iván

2017-01-01

Paraoxonase 1 (PON1), a high-density lipoprotein-associated antioxidant enzyme, hydrolyzes several organophosphate pesticides and oxidized lipids. The PON1 Q192R polymorphism affects the catalytic efficiency and is considered a risk factor for pesticide intoxication and cardiovascular disease (CVD) but the association is not consistent between individuals or populations. We aimed to study the association of PON1 Q192R polymorphism with CVD risk in coffee harvesters of central Colombia. Demographics were collected from 205 subjects via standardized questionnaires. Lipid profiles and serum butyrylcholinesterase (BChE) were measured by standard procedures. The calculated 10-year atherosclerotic CVD (ASCVD) risk was used as the cardiovascular risk estimate. Q192R genotype was determined by real-time PCR. Prevalence of hypertension, hypercholesterolemia, and the 10-year ASCVD risk was 33%, 62%, and 22%, respectively. BChE levels were no indicative of recent pesticide exposure, although a positive correlation was observed with BChE and hypercholesterolemia. The Q192R genotype frequencies were 38% (QQ), 44% (QR), and 18% (RR). We found an association of the 192Q genotype with hypertension. The results of this study signal the importance to evaluate the influence and potential interactions of BChE and PON1 192Q allele with known genetic and environmental factors implicated in the pathogenesis of CVD. PMID:29430251

Characterization of acetylcholinesterase-inhibition by itopride.

PubMed

Iwanaga, Y; Kimura, T; Miyashita, N; Morikawa, K; Nagata, O; Itoh, Z; Kondo, Y

1994-11-01

Itopride is a gastroprokinetic benzamide derivative. This agent inhibited both electric eel acetylcholinesterase (AChE) and horse serum butyrylcholinesterase (BuChE). The IC50 of itopride with AChE (2.04 +/- 0.27 microM) was, however, 100-fold less than that with BuChE, whereas in the case of neostigmine with AChE (11.3 +/- 3.4 nM), it was 10-fold less. The recovery of AChE activity inhibited by 10(-7) M neostigmine was partial, but that inhibited by up to 3 x 10(-5) M itopride was complete when the reaction mixture was subjected to ultrafiltration. Double reciprocal plots of the experimental data showed that both Km and Vmax were affected by itopride, suggesting that the inhibition is a "mixed" type, although primarily being an uncompetitive one. The inhibitory effect of itopride on cholinesterase (ChE) activity in guinea pig gastrointestine was much weaker than that on pure AChE. However, in the presence of a low dose of diisopropyl fluorophosphate, just enough to inhibit BuChE but not AChE, the IC50s of itopride against ChE activities were found to be about 0.5 microM. In conclusion, itopride exerts reversible and a "mixed" type of inhibition preferably against AChE. The IC50 of itopride for electric eel and guinea pig gastrointestinal AChE inhibition was 200 times and 50 times as large as that of neostigmine, respectively.

B-esterase activities and blood cell morphology in the frog Leptodactylus chaquensis (Amphibia: Leptodactylidae) on rice agroecosystems from Santa Fe Province (Argentina).

PubMed

Attademo, Andrés M; Cabagna-Zenklusen, Mariana; Lajmanovich, Rafael C; Peltzer, Paola M; Junges, Celina; Bassó, Agustín

2011-01-01

Activity of B-esterases (BChE: butyrylcholinesterase and CbE: carboxylesterase using two model substrates: α-naphthyl acetate and 4-nitrophenyl valerate) in a native frog, Leptodactylus chaquensis from rice fields (RF1: methamidophos and RF2: cypermethrin and endosulfan sprayed by aircraft) and non-contaminated area (pristine forest) was measured. The ability of pyridine-2-aldoxime methochloride (2-PAM) to reactivate BChE levels was also explored. In addition, changes in blood cell morphology and parasite infection were determined. Mean values of plasma BChE activities were lower in samples from the two rice fields than in those from the reference site. CbE (4-nitrophenyl valerate) levels varied in the three sites studied, being highest in RF1. Frog plasma from RF1 showed positive reactivation of BChE activity after incubation with 2-PAM. Blood parameters of frogs from RF2 revealed morphological alterations (anisochromasia and immature erythrocytes frequency). Moreover, a major infection of protozoan Trypanosoma sp. in individuals from the two rice fields was detected. We suggest that integrated use of several biomarkers (BChE and CBEs, chemical reactivation of plasma with 2-PAM, and blood cell parameters) may be a promising procedure for use in biomonitoring programmes to diagnose pesticide exposure of wild populations of this frog and other native anuran species in Argentina.

Syntheses, cholinesterases inhibition, and molecular docking studies of pyrido[2,3-b]pyrazine derivatives.

PubMed

Hameed, Abdul; Zehra, Syeda T; Shah, Syed J A; Khan, Khalid M; Alharthy, Rima D; Furtmann, Norbert; Bajorath, Jürgen; Tahir, Muhammad N; Iqbal, Jamshed

2015-11-01

Cholinesterases, acetylcholinesterase (AChE) and butyrylcholinesterase (BChE), have a role in cholinergic deficit which evidently leads to Alzheimer's disease (AD). Inhibition of cholinesterases with small molecules is an attractive strategy in AD therapy. This study demonstrates synthesis of pyrido[2,3-b]pyrazines (6a-6q) series, their inhibitory activities against both cholinesterases, AChE and BChE, and molecular docking studies. The bioactivities data of pyrido[2,3-b]pyrazines showed 3-(3'-nitrophenyl)pyrido[2,3-b]pyrazine 6n a potent dual inhibitor among the series against both AChE and BChE with IC50 values of 0.466 ± 0.121 and 1.89 ± 0.05 μm, respectively. The analogues 3-(3'-methylphenyl)pyrido[2,3-b]pyrazine 6c and 3-(3'-fluorophenyl)pyrido[2,3-b]pyrazine 6f were found to be selective inhibition for BChE with IC50 values of 0.583 ± 0.052 μm and AChE with IC50 value of 0.899 ± 0.10 μm, respectively. Molecular docking studies of the active compounds suggested the putative binding modes with cholinesterases. The potent compounds among the series could potentially serves as good leads for the development of new cholinesterase inhibitors. © 2015 John Wiley & Sons A/S.

Effects of cholinesterase inhibitors on the activities and protein levels of cholinesterases in the cerebrospinal fluid of patients with Alzheimer's disease: a review of recent clinical studies.

PubMed

Darreh-Shori, T; Soininen, H

2010-02-01

Alzheimer's disease (AD) is a progressive neurodegenerative disease characterized by cognitive decline associated with a deficit in cholinergic function. Inhibitors of acetylcholinesterase (AChE) and/or butyrylcholinesterase (BuChE), such as donepezil, galantamine or rivastigmine, are widely prescribed as symptomatic treatments for AD. These agents exhibit a wide variation in their pharmacological properties. Here we review clinical data from 1998 to 2009 investigating the effect of different cholinesterase inhibitor treatments on the levels and activities of cholinesterases in the cerebrospinal fluid (CSF) of AD patients. These studies suggest that treatment with rapidly-reversible cholinesterase inhibitors (e.g. donepezil, galantamine, tacrine) are associated with marked and significant upregulation of AChE activities and protein levels in the CSF of AD patients. In contrast, pseudo-irreversible cholinesterase inhibition (e.g. rivastigmine) is associated with a significant decrease in both CSF AChE and BuChE activities, with no upregulation of CSF protein levels. Additionally, donepezil is associated with a decrease in the level of the AChE-R isoform relative to the synaptic AChE-S isoform, whereas rivastigmine seems to increase this ratio. These findings suggest that these agents exert different effects on CSF cholinesterases. The clinical effects of these pharmacological differences are yet to be fully established.

The progress in the cholinesterase quantification methods.

PubMed

Holas, Ondrej; Musilek, Kamil; Pohanka, Miroslav; Kuca, Kamil

2012-12-01

Determination of acetylcholinesterase and butyrylcholinesterase activity has become an important tool in drug design and discovery as well as in medicine and toxicology. There are a large number of compounds that are able to modulate cholinesterase activity. These compounds can be used for pharmacological management of various disorders (e.g., Alzheimer's disease, myasthenia Gravis). Moreover, organophosphate poisoning is frequently diagnosed via a cholinesterase activity assay. This broad variety of methods has been developed over the past decades for cholinesterase activity quantification. This review provides a summary of the methods that are based on specific properties of cholinesterases and their interactions with native or artificial substrates. The authors also aim to provide an overview of different techniques used for the determination of quantitative cholinesterase activity. Specifically, the authors describe and discuss the manometric, potentiometric, titrimetric, photometric, fluorometric, and radioisotopic methods. Existing methods are able to cover most of the problems that arise during cholinesterase activity determination. Colorimetry according to Ellman has proved to be the most useful and versatile approach. It may be used in various protocols for the determination of pesticide or nerve agent exposure or for the development of new drugs. Its possible improvement lies in optimization of hemoglobin-rich samples. The progress of the most common methods (including Ellman) depends on miniaturization and modern physical platforms (e.g., optical fibers, chip methods, or nanotechnologies).

Processing of Cholinesterase-like α/β-Hydrolase Fold Proteins: Alterations Associated with Congenital Disorders

PubMed Central

De Jaco, Antonella; Comoletti, Davide; Dubi, Noga; Camp, Shelley; Taylor, Palmer

2016-01-01

The α/β hydrolase fold family is perhaps the largest group of proteins presenting significant structural homology with divergent functions, ranging from catalytic hydrolysis to heterophilic cell adhesive interactions to chaperones in hormone production. All the proteins of the family share a common three-dimensional core structure containing the α/β-hydrolase fold domain that is crucial for proper protein function. Several mutations associated with congenital diseases or disorders have been reported in conserved residues within the α/β-hydrolase fold domain of cholinesterase-like proteins, neuroligins, butyrylcholinesterase and thyroglobulin. These mutations are known to disrupt the architecture of the common structural domain either globally or locally. Characterization of the natural mutations affecting the α/β-hydrolase fold domain in these proteins has shown that they mainly impair processing and trafficking along the secretory pathway causing retention of the mutant protein in the endoplasmic reticulum. Studying the processing of α/β-hydrolase fold mutant proteins should uncover new functions for this domain, that in some cases require structural integrity for both export of the protein from the ER and for facilitating subunit dimerization. A comparative study of homologous mutations in proteins that are closely related family members, along with the definition of new three-dimensional crystal structures, will identify critical residues for the assembly of the α/β-hydrolase fold. PMID:21933121

HPTLC Fingerprinting and Cholinesterase Inhibitory and Metal-Chelating Capacity of Various Citrus Cultivars and
Olea europaea

PubMed Central

Senol, Fatma Sezer; Ankli, Anita; Reich, Eike

2016-01-01

Summary Inhibitory activity of thirty-one ethanol extracts obtained from albedo, flavedo, seed and leaf parts of 17 cultivars of Citrus species from Turkey, the bark and leaves of Olea europaea L. from two locations (Turkey and Cyprus) as well as caffeic acid and hesperidin was tested against acetylcholinesterase (AChE) and butyrylcholinesterase (BChE), related to the pathogenesis of Alzheimer’s disease, using ELISA microtiter assays at 500 µg/mL. Metal-chelating capacity of the extracts was also determined. BChE inhibitory effect of the Citrus sp. extracts was from (7.7±0.7) to (70.3±1.1) %, whereas they did not show any inhibition against AChE. Cholinesterase inhibitory activity of the leaf and bark ethanol extracts of O. europaea was very weak ((10.2±3.1) to (15.0±2.3) %). The extracts had either no or low metal-chelating capacity at 500 µg/mL. HPTLC fingerprinting of the extracts, which indicated a similar phytochemical pattern, was also done using the standards of caffeic acid and hesperidin with weak cholinesterase inhibition. Among the screened extracts, the albedo extract of C. limon ‘Interdonato’, the flavedo extracts of ‘Kara Limon’ and ‘Cyprus’ cultivars and the seed extract of C. maxima appear to be promising as natural BChE inhibitors. PMID:27956858

Evaluation of fruit extracts of six Turkish Juniperus species for their antioxidant, anticholinesterase and antimicrobial activities.

PubMed

Oztürk, Mehmet; Tümen, İbrahim; Uğur, Aysel; Aydoğmuş-Öztürk, Fatma; Topçu, Gülaçtı

2011-03-30

Juniperus L. (Cupressaceae) species are mostly spread out in the Northern Hemisphere of the world, and some of them are used as folkloric medicines. The fruits of some species are eaten. Since oxidative stress is one of the reasons for neurodegeneration and is associated with the Alzheimer's disease (AD), the extracts prepared from the fruits of six Juniperus species were screened for their antioxidant activity. Therefore, the extracts were also evaluated against acetylcholinesterase (AChE) and butyrylcholinesterase (BChE), which are chief enzymes in the pathogenesis of AD. In addition, antimicrobial activity was also evaluated. In the β-carotene-linoleic acid assay, acetone extracts of J. oxycedrus subsp. oxycedrus, J. sabina and J. excelsa, and methanol extracts of J. phoenicea and J. sabina, effectively inhibited oxidation of linoleic acid. The hexane extracts of J. oxycedrus subsp. oxycedrus, J. foetidissima and J. phoenicea showed remarkable inhibitory effect against AChE and BChE. Because of their high antioxidant activity, J. excelsa, J. oxycedrus subsp. oxycedrus, J. sabina and J. phoenicia might be used in the food industry as preservative agents or extension of the shelf-life of raw and processed foods. Since the hexane extracts of J. oxycedrus subsp. oxycedrus and J. foetidissima demonstrated significant anticholinesterase activity they should be considered as a potential source for anticholinesterase agents. Copyright © 2010 Society of Chemical Industry.

Novel Organophosphate Ligand O-(2-Fluoroethyl)-O-(p-Nitrophenyl)Methylphosphonate: Synthesis, Hydrolytic Stability and Analysis of the Inhibition and Reactivation of Cholinesterases.

PubMed

Chao, Chih-Kai; Ahmed, S Kaleem; Gerdes, John M; Thompson, Charles M

2016-11-21

The organophosphate O-(2-fluoroethyl)-O-(p-nitrophenyl) methyphosphonate 1 is the first-in-class, fluorine-18 radiolabeled organophosphate inhibitor ([ 18 F]1) of acetylcholinesterase (AChE). In rats, [ 18 F]1 localizes in AChE rich regions of the brain and other tissues where it likely exists as the (CH 3 )( 18 FCH 2 CH 2 O)P(O)-AChE adduct (ChE-1). Characterization of this adduct would define the inhibition mechanism and subsequent postinhibitory pathways and reactivation rates. To validate this adduct, the stability (hydrolysis) of 1 and ChE-1 reactivation rates were determined. Base hydrolysis of 1 yields p-nitrophenol and (CH 3 ) (FCH 2 CH 2 O)P(O)OH with pseudo first order rate constants (k obsd ) at pH 7.4 (PBS) of 3.25 × 10 -4 min -1 (t 1/2 = 35.5 h) at 25 °C and 8.70 × 10 -4 min -1 (t 1/2 = 13.3 h) at 37 °C. Compound 1 was a potent inhibitor of human acetylcholinesterase (HuAChE; k i = 7.5 × 10 5 M -1 min -1 ), electric eel acetylcholinesterase (EEAChE) (k i = 3.0 × 10 6 M -1 min -1 ), and human serum butyrylcholinesterase (HuBChE; 1.95 × 10 5 M -1 min -1 ). Spontaneous and oxime-mediated reactivation rates for the (CH 3 ) (FCH 2 CH 2 O)P(O)-serine ChE adducts using 2-PAM (10 μM) were (a) HuAChE 8.8 × 10 -5 min -1 (t 1/2 = 131.2 h) and 2.41 × 10 -2 min -1 (t 1/2 = 0.48 h), (b) EEAChE 9.32 × 10 -3 min -1 (t 1/2 = 1.24 h) and 3.33 × 10 -2 min -1 (t 1/2 = 0.35 h), and (c) HuBChE 1.16 × 10 -4 min -1 (t 1/2 = 99.6 h) and 4.19 × 10 -2 min -1 (t 1/2 = 0.27 h). All ChE-1 adducts undergo rapid and near complete restoration of enzyme activity following addition of 2-PAM (30 min), and no aging was observed for either reactivation process. The fast reactivation rates and absence of aging of ChE-1 adducts are explained on the basis of the electron-withdrawing fluorine group that favors the nucleophilic reactivation processes but disfavors cation-based dealkylation aging mechanisms. Therefore, the likely fate of radiolabeled compound 1 in vivo is the formation of (CH 3 )(FCH 2 CH 2 O)P(O)-serine adducts and monoacid (CH 3 )(FCH 2 CH 2 O)P(O)OH from hydrolysis and reactivation.

Alteration of paraoxonase, arylesterase and lactonase activities in people around fluoride endemic area of Tamil Nadu, India.

PubMed

Arulkumar, Mani; Vijayan, Raji; Penislusshiyan, Sakayanathan; Sathishkumar, Palanivel; Angayarkanni, Jayaraman; Palvannan, Thayumanavan

2017-08-01

Toxicity due to excess fluoride concentration in drinking water is of great concern in people who rely only on the ground water as their water source in many region of the world. We collected samples and examined the toxicity of fluoride in a population residing at Salem, Dharmapuri and Krishnagiri districts of Tamil Nadu, India and measured HDL bound enzyme (PON1), erythrocyte membrane bound enzymes (acetylcholinesterase, AChE) and adenosine 5' triphosphatase (ATPases), plasma enzyme (butyrylcholinesterase, BChE) and rate limiting enzyme in heme biosynthesis (delta aminolevulinic acid dehydratase, δ-ALAD) activities. In fluorosis patients, formation of lipid peroxidation product was more in erythrocytes than in plasma. The observation further revealed that there was 50% reduction in the activity of HDL bound anti atherogenic enzyme-paraoxonase (PON1). The activities of membrane bound and signaling enzymes (acetylcholinesterase - AChE and adenosine 5' triphosphatase - ATPase) of erythrocyte were also diminished. These results suggested that there was defectiveness in the signaling and energy metabolism in fluorosis patients. Altered isoenzyme pattern of lactate dehydrogenase (LDH) in fluorosis samples was observed. Furthermore, the result suggested that both the heart (LDH 1) and liver (LDH 5) were most affected by fluoride toxicity. The study also provided reference values for tests which are used to predict the severity of fluoride toxicity. The toxic effect of fluoride was due to the collective effects on vital protective system rather than single factor. Copyright © 2017 Elsevier B.V. All rights reserved.

Predicting targets of compounds against neurological diseases using cheminformatic methodology

NASA Astrophysics Data System (ADS)

Nikolic, Katarina; Mavridis, Lazaros; Bautista-Aguilera, Oscar M.; Marco-Contelles, José; Stark, Holger; do Carmo Carreiras, Maria; Rossi, Ilaria; Massarelli, Paola; Agbaba, Danica; Ramsay, Rona R.; Mitchell, John B. O.

2015-02-01

Recently developed multi-targeted ligands are novel drug candidates able to interact with monoamine oxidase A and B; acetylcholinesterase and butyrylcholinesterase; or with histamine N-methyltransferase and histamine H3-receptor (H3R). These proteins are drug targets in the treatment of depression, Alzheimer's disease, obsessive disorders, and Parkinson's disease. A probabilistic method, the Parzen-Rosenblatt window approach, was used to build a "predictor" model using data collected from the ChEMBL database. The model can be used to predict both the primary pharmaceutical target and off-targets of a compound based on its structure. Molecular structures were represented based on the circular fingerprint methodology. The same approach was used to build a "predictor" model from the DrugBank dataset to determine the main pharmacological groups of the compound. The study of off-target interactions is now recognised as crucial to the understanding of both drug action and toxicology. Primary pharmaceutical targets and off-targets for the novel multi-target ligands were examined by use of the developed cheminformatic method. Several multi-target ligands were selected for further study, as compounds with possible additional beneficial pharmacological activities. The cheminformatic targets identifications were in agreement with four 3D-QSAR (H3R/D1R/D2R/5-HT2aR) models and by in vitro assays for serotonin 5-HT1a and 5-HT2a receptor binding of the most promising ligand ( 71/MBA-VEG8).

Oxidative stress in dairy cows seropositives for Neospora caninum.

PubMed

Glombowsky, Patrícia; Bottari, Nathieli B; Klauck, Vanderlei; Fávero, Juscivete F; Soldá, Natan M; Baldissera, Matheus D; Perin, Gessica; Morsch, Vera M; Schetinger, Maria Rosa C; Stefani, Lenita M; Da Silva, Aleksandro S

2017-10-01

Bovine neosporosis is caused by the protozoan Neospora caninum and is one of the major causes of abortion in cows. Cattle are intermediate hosts of this parasite and may have asymptomatic or symptomatic infections. Therefore, the aim of this study was to evaluate oxidative stress marker reactive oxygen species (ROS), thiobarbituric reactive acid substances (TBARS) levels, glutathione S-transferase (GST), adenosine deaminase (ADA), and butyrylcholinesterase (BChE) activities in dairy cows seropositives for N. caninum (asymptomatic or symptomatic). Dairy cows (n=90) were tested by immunofluorescent antibody assay (IFA) for N. caninum and divided accordingly into three groups: the group A (seronegatives, n=30), the group B (seropositives and asymptomatic, n=30), and the group C (seropositives and symptomatic, n=30). It was observed increased levels of TBARS and reduced (P<0.05) BChE activity in seropositives either asymptomatic or symptomatic animals. ROS levels and ADA activity increased, and GST activity decreased (P<0.05) only in seropositives symptomatic dairy cows (the group C) compared to seronegatives dairy cows (the group A). Based on these results, it was observed that seropositive animals showed cell damage associated with oxidative stress and inflammation, mainly in those with symptomatic infections. Increased seric ROS levels and BChE activity may have influenced N. caninum pathogenesis in symptomatic animals due to increased cell damage and exacerbated inflammatory response, leading to the development of clinical signs. Copyright © 2017 Elsevier Ltd. All rights reserved.

Design, evaluation and structure-activity relationship studies of the AChE reactivators against organophosphorus pesticides.

PubMed

Musilek, Kamil; Dolezal, Martin; Gunn-Moore, Frank; Kuca, Kamil

2011-07-01

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. © 2009 Wiley Periodicals, Inc.

Evaluation of Antioxidant, Antidiabetic and Anticholinesterase Activities of Smallanthus sonchifolius Landraces and Correlation with Their Phytochemical Profiles

PubMed Central

Russo, Daniela; Valentão, Patrícia; Andrade, Paula B.; Fernandez, Eloy C.; Milella, Luigi

2015-01-01

The present study aimed to investigate the phytochemical profile of leaf methanol extracts of fourteen Smallanthus sonchifolius (yacon) landraces and their antioxidant, anticholinesterase and antidiabetic activities that could lead to the finding of more effective agents for the treatment and management of Alzheimer’s disease and diabetes. For this purpose, antioxidant activity was assessed using different tests: ferric reducing ability power (FRAP), 2,2-diphenyl-1-picryl hydrazyl (DPPH), nitric oxide (˙NO) and superoxide (O2˙−) scavenging and lipid peroxidation inhibition assays. Anticholinesterase activity was investigated by quantifying the acetylcholinesterase (AChE) and butyrylcholinesterase (BChE) inhibitory activities, whereas antidiabetic activity was investigated by α-amylase and α-glucosidase inhibition tests. To understand the contribution of metabolites, phytochemical screening was also performed by high performance liquid chromatography-diode array detector (HPLC-DAD) system. Among all, methanol extract of PER09, PER04 and ECU44 landraces exhibited the highest relative antioxidant capacity index (RACI). ECU44 was found to be rich in 4,5-di-O-caffeoylquinic acid (CQA) and 3,5-di-O-CQA and displayed a good α-amylase and α-glucosidase inhibition, showing the lowest IC50 values. Flavonoids, instead, seem to be involved in the AChE and BChE inhibition. The results of this study revealed that the bioactive compound content differences could be determinant for the medicinal properties of this plant especially for antioxidant and antidiabetic activities. PMID:26263984

Multitarget Therapeutic Leads for Alzheimer's Disease: Quinolizidinyl Derivatives of Bi- and Tricyclic Systems as Dual Inhibitors of Cholinesterases and β-Amyloid (Aβ) Aggregation.

PubMed

Tonelli, Michele; Catto, Marco; Tasso, Bruno; Novelli, Federica; Canu, Caterina; Iusco, Giovanna; Pisani, Leonardo; Stradis, Angelo De; Denora, Nunzio; Sparatore, Anna; Boido, Vito; Carotti, Angelo; Sparatore, Fabio

2015-06-01

Multitarget therapeutic leads for Alzheimer's disease were designed on the models of compounds capable of maintaining or restoring cell protein homeostasis and of inhibiting β-amyloid (Aβ) oligomerization. Thirty-seven thioxanthen-9-one, xanthen-9-one, naphto- and anthraquinone derivatives were tested for the direct inhibition of Aβ(1-40) aggregation and for the inhibition of electric eel acetylcholinesterase (eeAChE) and horse serum butyrylcholinesterase (hsBChE). These compounds are characterized by basic side chains, mainly quinolizidinylalkyl moieties, linked to various bi- and tri-cyclic (hetero)aromatic systems. With very few exceptions, these compounds displayed inhibitory activity on both AChE and BChE and on the spontaneous aggregation of β-amyloid. In most cases, IC50 values were in the low micromolar and sub-micromolar range, but some compounds even reached nanomolar potency. The time course of amyloid aggregation in the presence of the most active derivative (IC50 =0.84 μM) revealed that these compounds might act as destabilizers of mature fibrils rather than mere inhibitors of fibrillization. Many compounds inhibited one or both cholinesterases and Aβ aggregation with similar potency, a fundamental requisite for the possible development of therapeutics exhibiting a multitarget mechanism of action. The described compounds thus represent interesting leads for the development of multitarget AD therapeutics. © 2015 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

Acquisition and reinstatement of ethanol-induced conditioned place preference in rats: Effects of the cholinesterase inhibitors donepezil and rivastigmine.

PubMed

Gawel, Kinga; Labuz, Krzysztof; Gibula-Bruzda, Ewa; Jenda, Malgorzata; Marszalek-Grabska, Marta; Silberring, Jerzy; Kotlinska, Jolanta H

2016-07-01

The present study examined the influence of the cholinesterase inhibitors donepezil (a selective inhibitor of acetylcholinesterase) and rivastigmine (also an inhibitor of butyrylcholinesterase) on the acquisition and reinstatement of ethanol-induced conditioned place preference (CPP) in rats. Before the CPP procedure, animals received a single injection of ethanol (0.5 g/kg, 10% w/v, intraperitoneally [i.p.]) for 15 days. The ethanol-induced CPP (biased method) was developed by four injections of ethanol (0.5 g/kg, 10% w/v, i.p.) every second day. Control rats received saline instead of ethanol. Donepezil (0.5, 1 or 3 mg/kg, i.p.) or rivastigmine (0.03, 0.5 or 1 mg/kg, i.p.) were administered before ethanol during conditioning or before the reinstatement of ethanol-induced CPP. The cholinesterase inhibitors were equally effective in increasing (dose dependently) the acquisition of ethanol-induced CPP. Furthermore, priming injections of both inhibitors reinstated (cross-reinstatement) the ethanol-induced CPP with similar efficacy. These effects of both cholinesterase inhibitors were reversed by mecamylamine (3 mg/kg, i.p.), a nicotinic acetylcholine receptor antagonist, but not by scopolamine (0.5 mg/kg, i.p.), a muscarinic acetylcholine receptor antagonist. Thus, our results show that the cholinergic system is involved in the reinforcing properties of ethanol, and nicotinic acetylcholine receptors play an important role in the relapse to ethanol-seeking behaviour. © The Author(s) 2016.