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Wang F, Liu X, Lu CH, Willner I. Cysteine-mediated aggregation of Au nanoparticles: the development of a H2O2 sensor and oxidase-based biosensors. ACS NANO 2013; 7:7278-7286. [PMID: 23829431 DOI: 10.1021/nn402810x] [Citation(s) in RCA: 119] [Impact Index Per Article: 10.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/02/2023]
Abstract
The cysteine-stimulated aggregation of Au nanoparticles (Au NPs) is used as an auxiliary reporting system for the optical detection of H2O2, for optical probing of the glucose oxidase (GOx) and the catalyzed oxidation of glucose, for probing the biocatalytic cascade composed of acetylcholine esterase/choline oxidase (AChE/ChOx), and for following the inhibition of AChE. The analytical paradigm is based on the I(-)-catalyzed oxidation of cysteine by H2O2 to cystine, a process that prohibits the cysteine-triggered aggregation of the Au NPs. The system enabled the analysis of H2O2 with a detection limit of 2 μM. As the GOx-biocatalyzed oxidation of glucose yields H2O2, and the AChE/ChOx cascade leads to the formation of H2O2, the two biocatalytic processes could be probed by the cysteine-stimulated aggregation of the Au NPs. Since AChE is inhibited by 1,5-bis(4-allyldimethylammonium phenyl)pentane-3-one dibromide, the biocatalytic AChE/ChOx cascade is inhibited by the inhibitor, thus leading to the enhanced cysteine-mediated aggregation of the NPs. The results suggest the potential implementation of the cysteine-mediated aggregation of Au NPs in the presence of AChE/ChOx as a sensing platform for the optical detection of chemical warfare agents.
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Affiliation(s)
- Fuan Wang
- Institute of Chemistry, The Center for Nanoscience and Nanotechnology, The Hebrew University of Jerusalem, Jerusalem 91904, Israel
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2
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Wang M, Gu X, Zhang G, Zhang D, Zhu D. Continuous colorimetric assay for acetylcholinesterase and inhibitor screening with gold nanoparticles. LANGMUIR : THE ACS JOURNAL OF SURFACES AND COLLOIDS 2009; 25:2504-2507. [PMID: 19154124 DOI: 10.1021/la803870v] [Citation(s) in RCA: 95] [Impact Index Per Article: 6.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/27/2023]
Abstract
We report herein a new colorimetric assay method for acetylcholinesterase (AChE) activity and its inhibitor screening by making use of the following facts: (1) the aggregation of gold nanoparticles (Au-NPs) results in the red-shift of the plasmon absorption due to interparticle plasmon interactions and (2) AChE can catalyze the hydrolysis of acetylthiocholine into thiocholine which can induce the aggregation of Au-NPs. With this convenient method, the activity of AChE with a concentration as low as 0.6 mU/mL can be assayed. Moreover, this assay method is also useful for screening inhibitors of AChE. Given its simplicity and easy-operation, this method may extend to high-throughput screening of AChE inhibitors and relevant drug discovery.
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Affiliation(s)
- Ming Wang
- Beijing National Laboratory for Molecular Sciences, Organic Solids Laboratory, Institute of Chemistry, Chinese Academy of Sciences, Beijing 100190, China
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Taylor JT, Davis E, Dabisch P, Horsmon M, Matson K, Crouse C, Mioduszewski R. Acute toxic effects of inhaled dichlorvos vapor on respiratory mechanics and blood cholinesterase activity in guinea pigs. Inhal Toxicol 2008; 20:465-72. [PMID: 18368617 DOI: 10.1080/08958370701805709] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/22/2022]
Abstract
Using a modified noninvasive volume-displacement plethysmography system, we investigated the effects of inhaled dichlorvos (2,2-dimethyl-dichlorovinyl phosphate, or DDVP) vapor on the respiratory mechanics and blood cholinesterase activity of guinea pigs. Data revealed significant dose-dependent changes in several pulmonary parameters. Animals exposed to a DDVP concentration of 35 mg/m(3) did not show any significant changes in frequency, tidal volume, or minute ventilation. However, animals exposed to 55 mg/m(3) DDVP showed significantly decreased respiratory frequency and significantly increased tidal volume with no significant changes in minute ventilation. Similarly, animals exposed to 75 mg/m(3) DDVP showed significantly decreased respiratory frequency along with significantly increased tidal volume. The decreased respiratory frequency was large enough in the high exposure group to offset the increased tidal volume. This effect resulted in significantly decreased minute ventilation by the end of exposure, which remained attenuated 10 min after exposure. An analysis of whole-blood cholinesterase activity revealed significantly decreased activity for both acetylcholinesterase (AChE) and butyl-cholinesterase (BChE). Peak inhibition occurred for both enzymes at the end of exposure for all three concentrations and rapidly recovered within several minutes of exposure. Analysis of blood samples using gas chromatography-mass spectroscopy (GC-MS) revealed that minute ventilation may only play a minimal role in the dosimetry of inhaled DDVP vapor.
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Affiliation(s)
- James T Taylor
- National Academy of Sciences-National Research Council, Washington, DC, USA.
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Gill R, Bahshi L, Freeman R, Willner I. Optical Detection of Glucose and Acetylcholine Esterase Inhibitors by H2O2-Sensitive CdSe/ZnS Quantum Dots. Angew Chem Int Ed Engl 2008. [DOI: 10.1002/ange.200704794] [Citation(s) in RCA: 68] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/05/2022]
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Gill R, Bahshi L, Freeman R, Willner I. Optical Detection of Glucose and Acetylcholine Esterase Inhibitors by H2O2-Sensitive CdSe/ZnS Quantum Dots. Angew Chem Int Ed Engl 2008; 47:1676-9. [DOI: 10.1002/anie.200704794] [Citation(s) in RCA: 210] [Impact Index Per Article: 13.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/10/2022]
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Xiao Y, Pavlov V, Shlyahovsky B, Willner I. An OsII-Bisbipyridine-4-Picolinic Acid Complex Mediates the Biocatalytic Growth of Au Nanoparticles: Optical Detection of Glucose and Acetylcholine Esterase Inhibition. Chemistry 2005; 11:2698-704. [PMID: 15729675 DOI: 10.1002/chem.200400988] [Citation(s) in RCA: 43] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/07/2022]
Abstract
The complex Os(II)-bisbipyridine-4-picolinic acid, [Os(bpy)(2)PyCO(2)H](2+) (1), mediates the biocatalyzed growth of Au nanoparticles, Au NPs, and enables the spectroscopic assay of biocatalyzed transformations and enzyme inhibition by following the Au NP plasmon absorbance. In one system, [Os(bpy)(2)PyCO(2)H](2+) mediates the biocatalyzed oxidation of glucose and the growth of Au NPs in the presence of glucose oxidase, GOx, AuCl(4) (-), citrate and Au NP seeds. The mechanism of the Au NPs growth involves the oxidation of the [Os(bpy)(2)PyCO(2)H](2+) complex by AuCl(4) (-) to form [Os(bpy)(2)PyCO(2)H](3+) and Au(I). The [Os(bpy)(2)PyCO(2)H](3+) complex mediates the GOx biocatalyzed oxidation of glucose and the regeneration of the mediator 1. Citrate reduces Au(I) and enlarges the Au seeds by the catalytic deposition of gold on the Au NP seeds. In the second system, the enzyme acetylcholine esterase, AChE, is assayed by the catalytic growth of the Au NPs. The hydrolysis of acetylcholine (2) by AChE to choline is followed by the [Os(bpy)(2)PyCO(2)H](3+) mediated oxidation of choline to betaine and the concomitant growth of the Au NPs. The mediated growth of the Au NPs is inhibited by 1,5-bis(4-allyldimethylammonium-phenyl)pentane-3-one dibromide (3). A competitive inhibition process was demonstrated (K(M)=0.13 mM, K(I)=2.6 microM) by following the growth of the Au NPs.
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Affiliation(s)
- Yi Xiao
- Institute of Chemistry, The Hebrew University of Jerusalem, Jerusalem 91904, Israel
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Pavlov V, Xiao Y, Willner I. Inhibition of the acetycholine esterase-stimulated growth of Au nanoparticles: nanotechnology-based sensing of nerve gases. NANO LETTERS 2005; 5:649-53. [PMID: 15826103 DOI: 10.1021/nl050054c] [Citation(s) in RCA: 145] [Impact Index Per Article: 7.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/13/2023]
Abstract
The acetylcholine esterase, AChE, mediated hydrolysis of acetylthiocholine (1) yields a reducing agent thiocholine (2) that stimulates the catalytic enlargement of Au NP seeds in the presence of AuCl(4)(-). The reductive enlargement of the Au NPs is controlled by the concentration of the substrate (1) and by the activity of the enzyme. The catalytic growth of the Au NPs is inhibited by 1,5-bis(4-allyldimethylammoniumphenyl)pentane-3-one dibromide (3) or by diethyl p-nitrophenyl phosphate (paraoxon; 4), thus enabling a colorimetric test for AChE inhibitors. The colorimetric assay was also developed on glass supports.
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Affiliation(s)
- Valeri Pavlov
- Institute of Chemistry, The Hebrew University of Jerusalem, Jerusalem, 91904 Israel
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Flüge T, Hoymann HG, Hohlfeld J, Heinrich U, Fabel H, Wagner TO, Forssmann WG. Type A natriuretic peptides exhibit different bronchoprotective effects in rats. Eur J Pharmacol 1994; 271:395-402. [PMID: 7705439 DOI: 10.1016/0014-2999(94)90799-4] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/26/2023]
Abstract
The protective effect of 11.4, 22.8 or 45.6 pmol/kg/min cardiodilatin/atrial natriuretic peptide (CDD/ANP-(99-126)), urodilatin (CDD/ANP-(95-126)) or vehicle intravenously against acetylcholine-induced bronchoconstriction was compared in spontaneously breathing, halothane-anesthetized Wistar rats. The inhalation of acetylcholine induced significant alterations of the spontaneous breathing parameters evaluated by whole-body plethysmography without significant differences between the treatment groups. Forced parameters detect airflow changes with a greater sensitivity and were measured in hyperventilation-induced temporary apnoea after the challenge. The forced expiratory volume in 0.1 s revealed a significant protective effect of 11.4 pmol/kg/min urodilatin compared to the controls whereas the parameters of the forced expiratory flow-volume curve were significantly preserved by 11.4 and 22.8 pmol/kg/min urodilatin (P < 0.05). Urodilatin showed protective effects against an acetylcholine challenge whereas CDD/ANP-(99-126) was without significant influence.
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Affiliation(s)
- T Flüge
- Department of Respiratory Medicine, Hannover Medical School, Germany
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Hoymann HG, Heinrich U, Beume R, Kilian U. Comparative investigation of the effects of zardaverine and theophylline on pulmonary function in rats. Exp Lung Res 1994; 20:235-50. [PMID: 7925141 DOI: 10.3109/01902149409064385] [Citation(s) in RCA: 16] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/27/2023]
Abstract
Zardaverine (Byk Gulden, Konstanz, Germany) is a new selective phosphodiesterase (PDE) III/IV inhibitor. The bronchodilating and bronchoprotective potency of zardaverine and the nonselective PDE inhibitor theophylline was compared by measuring typical spontaneous and forced respiratory function parameters in anesthetized female Wistar rats using whole-body plethysmography. Zardaverine (3, 10, 30 mumol/kg) and theophylline (30, 100, 300 mumol/kg), respectively, were given orally in 4% Methocel/0.9% saline solution 20 min before measurement. One week before treatment, control measurements were performed in the same animals after administration of the vehicle. When spontaneously breathing, the 30 mumol/kg zardaverine- (300 mumol/kg theophylline-) treated animals showed significant changes: a 23% (14% ns) decrease in lung resistance and a 43% (25%) increase in dynamic compliance. These changes can be interpreted as an indication of bronchodilation, since quasistatic lung compliance was unchanged. In the acetylcholine challenge test, treatment with only 10 mumol/kg zardaverine (but 300 mumol/kg theophylline) revealed significant changes compared to control measurement: a 37% (28%) lower resistance and 85% (44%) higher compliance. It has been determined that zardaverine is more than 30 times as potent as theophylline in inhibiting acetylcholine-induced bronchospasms, which is also supported by forced expiratory flow data.
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Affiliation(s)
- H G Hoymann
- Fraunhofer Institute of Toxicology and Aerosol Research, Hannover, Germany
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Norel X, Angrisani M, Labat C, Gorenne I, Dulmet E, Rossi F, Brink C. Degradation of acetylcholine in human airways: role of butyrylcholinesterase. Br J Pharmacol 1993; 108:914-9. [PMID: 8485630 PMCID: PMC1908169 DOI: 10.1111/j.1476-5381.1993.tb13486.x] [Citation(s) in RCA: 43] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/31/2023] Open
Abstract
1. Neostigmine and BW284C51 induced concentration-dependent contractions in human isolated bronchial preparations whereas tetraisopropylpyrophosphoramide (iso-OMPA) was inactive on airway resting tone. 2. Neostigmine (0.1 microM) or iso-OMPA (100 microM) increased acetylcholine sensitivity in human isolated bronchial preparations but did not alter methacholine or carbachol concentration-effect curves. 3. In the presence of iso-OMPA (10 microM) the bronchial rings were more sensitive to neostigmine. The pD2 values were, control: 6.05 +/- 0.15 and treated: 6.91 +/- 0.14. 4. Neostigmine or iso-OMPA retarded the degradation of acetylcholine when this substrate was exogenously added to human isolated airways. A marked reduction of acetylcholine degradation was observed in the presence of both inhibitors. Exogenous butyrylcholine degradation was prevented by iso-OMPA (10 microM) but not by neostigmine (0.1 microM). 5. These results suggest the presence of butyrylcholinesterase activity in human bronchial muscle and this enzyme may co-regulate the degradation of acetylcholine in this tissue.
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Affiliation(s)
- X Norel
- CNRS URA 1159, Centre Chirurgical Marie-Lannelongue, France
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Pauluhn J, Eben A. Altered lung function in rats after subacute exposure to n-butyl isocyanate. Arch Toxicol 1992; 66:118-25. [PMID: 1605726 DOI: 10.1007/bf02342505] [Citation(s) in RCA: 12] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/27/2022]
Abstract
The objectives of this study were to use pulmonary function tests, blood gas measurements and bronchoalveolar lung lavage (BAL) to characterize lesions in the respiratory tract of young adult male Wistar rats as a result of a 5-day exposure (6 h/day) to 0, 1.1, 6.2, 15 or 26 mg n-butyl isocyanate (n-BIC)/m3 air. Further objectives were to probe the diagnostic sensitivities of these procedures in comparison with more traditional evaluations (clinical observation, lung weight, histopathology). Measurements were performed during post-exposure weeks 2 and 5. Most rats exposed to 26 mg/m3 died or were sacrificed in a moribund state during post-exposure week 2. All other rats survived the exposure regimen. In rats exposed to 15 and 26 mg/m3 a significant decrease in body weight, laboured breathing, hypoactivity, nasal discharge, cyanosis, and hypothermia were observed. Pulmonary function measurements revealed increased total lung capacity (TLC) and residual volume (RV), decreased forced expiratory flow rates and quasi-static compliance in rats exposed to 26 mg/m3. At the end of the observation period rats exposed to 6.2 and 15 mg/m3 air were hyperresponsive to an acetylcholine bronchoprovocation aerosol. Arterial blood gas measurements revealed an arterial hypoxia and an increase in venous admixture, suggesting a severe mismatch of the ventilation-perfusion relationship. Biochemical and cellular components in BAL fluid (BALF) indicated a concentration dependent and protracted increase of polymorphonuclear leucocytes and further inflammatory parameters. In the 1.1 mg/m3 group BALF parameters were not significantly elevated. The major histopathological lesions of the lung were thickening of septa, emphysema, and intra-alveolar oedema in rats exposed to 26 mg/m3.(ABSTRACT TRUNCATED AT 250 WORDS)
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Affiliation(s)
- J Pauluhn
- Bayer AG, Department of Toxicology, Wuppertal, FRG
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Pauluhn J, Eben A, Kimmerle G. Functional, biochemical, and histopathological evidence of airway obstruction in rats following a four-hour acute inhalation exposure to n-butyl isocyanate. EXPERIMENTAL PATHOLOGY 1990; 40:197-202. [PMID: 2098266 DOI: 10.1016/s0232-1513(11)80295-1] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/30/2022]
Abstract
Pulmonary function, arterial blood gases, acid-base status, and bronchoalveolar lavage fluid (BALF) composition were assessed in male Wistar rats after a single 4-h exposure to 0, 7.6, 23.5 or 55.2 mg n-butyl isocyanate (n-BIC)/m3 air. No significant changes other than transient clinical signs were observed in the rats exposed to 7.6 mg/m3 air. Four weeks after exposure the animals of the 55.2 mg/m3 group showed significant effects: those were pronounced histopathological changes of airways and parenchyma, and elevated relative lung weight. The neutrophils, LDH, and protein in BALF were elevated. Quasi-static lung compliance, peak expiratory flow rate, mean mid expiratory flow rate were decreased whereas lung resistance, residual volume, and single breath CO-diffusing capacity were increased. Blood gas measurements revealed an elevation in hemoglobin, pH, arterio-alveolar oxygen difference, and venous admixture. Arterial pO2 and pCO2 were decreased. In animals exposed to 23.5 mg/m3 only marginal effects were detectable.
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Affiliation(s)
- J Pauluhn
- BAYER AG, Department of Toxicology, Wuppertal, FRG
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Different Methods Used in Acute and Subchronic Inhalation Studies of Potential Lung Irritants, with Particular Attention to Lung Function Measurements. Inhal Toxicol 1988. [DOI: 10.1007/978-3-642-61355-5_6] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register]
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