1
|
Steadman D, Atkinson BN, Zhao Y, Willis NJ, Frew S, Monaghan A, Patel C, Armstrong E, Costelloe K, Magno L, Bictash M, Jones EY, Fish PV, Svensson F. Virtual Screening Directly Identifies New Fragment-Sized Inhibitors of Carboxylesterase Notum with Nanomolar Activity. J Med Chem 2022; 65:562-578. [PMID: 34939789 DOI: 10.1021/acs.jmedchem.1c01735] [Citation(s) in RCA: 2] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/09/2023]
Abstract
Notum is a negative regulator of Wnt signaling acting through the hydrolysis of a palmitoleoylate ester, which is required for Wnt activity. Inhibitors of Notum could be of use in diseases where dysfunctional Notum activity is an underlying cause. A docking-based virtual screen (VS) of a large commercial library was used to shortlist 952 compounds for experimental validation as inhibitors of Notum. The VS was successful with 31 compounds having an IC50 < 500 nM. A critical selection process was then applied with two clusters and two singletons (1-4d) selected for hit validation. Optimization of 4d guided by structural biology identified potent inhibitors of Notum activity that restored Wnt/β-catenin signaling in cell-based models. The [1,2,4]triazolo[4,3-b]pyradizin-3(2H)-one series 4 represent a new chemical class of Notum inhibitors and the first to be discovered by a VS campaign. These results demonstrate the value of VS with well-designed docking models based on X-ray structures.
Collapse
Affiliation(s)
- David Steadman
- Alzheimer's Research UK UCL Drug Discovery Institute, University College London, The Cruciform Building, Gower Street, LondonWC1E 6BT, U.K
| | - Benjamin N Atkinson
- Alzheimer's Research UK UCL Drug Discovery Institute, University College London, The Cruciform Building, Gower Street, LondonWC1E 6BT, U.K
| | - Yuguang Zhao
- Division of Structural Biology, Wellcome Centre for Human Genetics, University of Oxford, The Henry Wellcome Building for Genomic Medicine, Roosevelt Drive, OxfordOX3 7BN, U.K
| | - Nicky J Willis
- Alzheimer's Research UK UCL Drug Discovery Institute, University College London, The Cruciform Building, Gower Street, LondonWC1E 6BT, U.K
| | - Sarah Frew
- Alzheimer's Research UK UCL Drug Discovery Institute, University College London, The Cruciform Building, Gower Street, LondonWC1E 6BT, U.K
| | - Amy Monaghan
- Alzheimer's Research UK UCL Drug Discovery Institute, University College London, The Cruciform Building, Gower Street, LondonWC1E 6BT, U.K
| | - Chandni Patel
- Alzheimer's Research UK UCL Drug Discovery Institute, University College London, The Cruciform Building, Gower Street, LondonWC1E 6BT, U.K
| | - Emma Armstrong
- Alzheimer's Research UK UCL Drug Discovery Institute, University College London, The Cruciform Building, Gower Street, LondonWC1E 6BT, U.K
| | - Kathryn Costelloe
- Alzheimer's Research UK UCL Drug Discovery Institute, University College London, The Cruciform Building, Gower Street, LondonWC1E 6BT, U.K
| | - Lorenza Magno
- Alzheimer's Research UK UCL Drug Discovery Institute, University College London, The Cruciform Building, Gower Street, LondonWC1E 6BT, U.K
| | - Magda Bictash
- Alzheimer's Research UK UCL Drug Discovery Institute, University College London, The Cruciform Building, Gower Street, LondonWC1E 6BT, U.K
| | - E Yvonne Jones
- Division of Structural Biology, Wellcome Centre for Human Genetics, University of Oxford, The Henry Wellcome Building for Genomic Medicine, Roosevelt Drive, OxfordOX3 7BN, U.K
| | - Paul V Fish
- Alzheimer's Research UK UCL Drug Discovery Institute, University College London, The Cruciform Building, Gower Street, LondonWC1E 6BT, U.K
| | - Fredrik Svensson
- Alzheimer's Research UK UCL Drug Discovery Institute, University College London, The Cruciform Building, Gower Street, LondonWC1E 6BT, U.K
| |
Collapse
|
2
|
Zhao Y, Svensson F, Steadman D, Frew S, Monaghan A, Bictash M, Moreira T, Chalk R, Lu W, Fish PV, Jones EY. Structural Insights into Notum Covalent Inhibition. J Med Chem 2021; 64:11354-11363. [PMID: 34292747 PMCID: PMC8365597 DOI: 10.1021/acs.jmedchem.1c00701] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/17/2021] [Indexed: 12/28/2022]
Abstract
The carboxylesterase Notum hydrolyzes a palmitoleate moiety from Wingless/Integrated(Wnt) ligands and deactivates Wnt signaling. Notum inhibitors can restore Wnt signaling which may be of therapeutic benefit for pathologies such as osteoporosis and Alzheimer's disease. We report the identification of a novel class of covalent Notum inhibitors, 4-(indolin-1-yl)-4-oxobutanoate esters. High-resolution crystal structures of the Notum inhibitor complexes reveal a common covalent adduct formed between the nucleophile serine-232 and hydrolyzed butyric esters. The covalent interaction in solution was confirmed by mass spectrometry analysis. Inhibitory potencies vary depending on the warheads used. Mechanistically, the resulting acyl-enzyme intermediate carbonyl atom is positioned at an unfavorable angle for the approach of the active site water, which, combined with strong hydrophobic interactions with the enzyme pocket residues, hinders the intermediate from being further processed and results in covalent inhibition. These insights into Notum catalytic inhibition may guide development of more potent Notum inhibitors.
Collapse
Affiliation(s)
- Yuguang Zhao
- Division
of Structural Biology, Wellcome Centre for Human Genetics, University of Oxford, Oxford OX3 7BN, U.K.
| | - Fredrik Svensson
- Alzheimer’s
Research UK UCL Drug Discovery Institute, University College London, Cruciform Building, Gower Street, London WC1E 6BT, U.K.
| | - David Steadman
- Alzheimer’s
Research UK UCL Drug Discovery Institute, University College London, Cruciform Building, Gower Street, London WC1E 6BT, U.K.
| | - Sarah Frew
- Alzheimer’s
Research UK UCL Drug Discovery Institute, University College London, Cruciform Building, Gower Street, London WC1E 6BT, U.K.
| | - Amy Monaghan
- Alzheimer’s
Research UK UCL Drug Discovery Institute, University College London, Cruciform Building, Gower Street, London WC1E 6BT, U.K.
| | - Magda Bictash
- Alzheimer’s
Research UK UCL Drug Discovery Institute, University College London, Cruciform Building, Gower Street, London WC1E 6BT, U.K.
| | - Tiago Moreira
- Centre
for Medicines Discovery, University of Oxford, Oxford OX3 7DQ, U.K.
| | - Rod Chalk
- Centre
for Medicines Discovery, University of Oxford, Oxford OX3 7DQ, U.K.
| | - Weixian Lu
- Division
of Structural Biology, Wellcome Centre for Human Genetics, University of Oxford, Oxford OX3 7BN, U.K.
| | - Paul V. Fish
- Alzheimer’s
Research UK UCL Drug Discovery Institute, University College London, Cruciform Building, Gower Street, London WC1E 6BT, U.K.
| | - E. Yvonne Jones
- Division
of Structural Biology, Wellcome Centre for Human Genetics, University of Oxford, Oxford OX3 7BN, U.K.
| |
Collapse
|
3
|
Reegan AD, Kumar PS, Asharaja AC, Devi C, Jameela S, Balakrishna K, Ignacimuthu S. Larvicidal and ovicidal activities of phenyl acetic acid isolated from Streptomyces collinus against Culex quinquefasciatus Say and Aedes aegypti L. (Diptera: Culicidae). Exp Parasitol 2021; 226-227:108120. [PMID: 34089701 DOI: 10.1016/j.exppara.2021.108120] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/11/2020] [Revised: 03/26/2021] [Accepted: 05/30/2021] [Indexed: 11/19/2022]
Abstract
The bio-efficacy of crude ethyl acetate extract, fractions and a compound phenyl acetic acid from the ethyl acetate extract of Streptomyces collinus was evaluated on Culex quinquefasciatus Say and Aedes aegypti L. mosquitoes (Diptera: Culicidae). The larvae were exposed to concentrations of 2.5, 5.0, 7.5 and 10.0 ppm for fractions and 0.5, 1.0, 1.5 and 2.0 ppm for compound. After 24 h, the larval mortality was assessed and the LC₅₀ and LC90 values were calculated. Similarly, per cent ovicidal activity was calculated for eggs after 120 h post treatment for phenyl acetic acid. Among the eleven fractions screened, fraction 7 from the ethyl acetate extract of Streptomyces collinus exhibited good larvicidal activity against both mosquito species. The LC50 and LC90 values of fraction 7 were 4.42, 6.23 ppm against Cx. quinquefasciatus larvae and 5.13, 14.51 ppm against Ae. aegypti larvae, respectively. Further, the isolated compound, phenyl acetic acid from fraction 7 recorded 100% larvicidal activity at 2 ppm concentration with LC50 and LC90 values of 2.07, 4.87 ppm on Cx. quinquefasciatus larvae and 3.81, 9.87 ppm on Ae. aegypti larvae, respectively. Phenyl acetic acid presented 50.3% and 42.0% ovicidal activity against Cx. quinquefasciatus and Ae. aegypti eggs at 2 ppm concentration after 120 h post treatment. The compound, phenyl acetic acid could be used in mosquito control programme.
Collapse
Affiliation(s)
- Appadurai Daniel Reegan
- National Centre for Disease Control, NTI Campus, Bellary Road, Bangalore, 560 003, Karnataka, India.
| | - Pachaiyappan Saravana Kumar
- CAS Key Laboratory of Tropical Marine Bio-resources and Ecology, Guangdong Key Laboratory of Marine Materia Medica, South China Sea Institute of Oceanology, Chinese Academy of Sciences, Guangzhou, 510 301, Guangdong, China.
| | - Antony Cruz Asharaja
- P.G. and Research Department of Zoology, Pasumpon Muthuramalinga Thevar College, Melaneelithanallur, Tenkasi, 627 953, Tamil Nadu, India
| | - Chitra Devi
- Department of Zoology, Sadakathullah Appa College (Autonomous), Rahmath Nagar, Tirunelveli, 627 011, Tamil Nadu, India
| | - Sithi Jameela
- Department of Zoology, Sadakathullah Appa College (Autonomous), Rahmath Nagar, Tirunelveli, 627 011, Tamil Nadu, India
| | - Kedike Balakrishna
- Entomology Research Institute, Loyola College, Chennai, 600 034, Tamil Nadu, India
| | | |
Collapse
|
4
|
Flanagan DJ, Pentinmikko N, Luopajärvi K, Willis NJ, Gilroy K, Raven AP, Mcgarry L, Englund JI, Webb AT, Scharaw S, Nasreddin N, Hodder MC, Ridgway RA, Minnee E, Sphyris N, Gilchrist E, Najumudeen AK, Romagnolo B, Perret C, Williams AC, Clevers H, Nummela P, Lähde M, Alitalo K, Hietakangas V, Hedley A, Clark W, Nixon C, Kirschner K, Jones EY, Ristimäki A, Leedham SJ, Fish PV, Vincent JP, Katajisto P, Sansom OJ. NOTUM from Apc-mutant cells biases clonal competition to initiate cancer. Nature 2021; 594:430-435. [PMID: 34079124 PMCID: PMC7615049 DOI: 10.1038/s41586-021-03525-z] [Citation(s) in RCA: 91] [Impact Index Per Article: 30.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/05/2020] [Accepted: 04/07/2021] [Indexed: 02/06/2023]
Abstract
The tumour suppressor APC is the most commonly mutated gene in colorectal cancer. Loss of Apc in intestinal stem cells drives the formation of adenomas in mice via increased WNT signalling1, but reduced secretion of WNT ligands increases the ability of Apc-mutant intestinal stem cells to colonize a crypt (known as fixation)2. Here we investigated how Apc-mutant cells gain a clonal advantage over wild-type counterparts to achieve fixation. We found that Apc-mutant cells are enriched for transcripts that encode several secreted WNT antagonists, with Notum being the most highly expressed. Conditioned medium from Apc-mutant cells suppressed the growth of wild-type organoids in a NOTUM-dependent manner. Furthermore, NOTUM-secreting Apc-mutant clones actively inhibited the proliferation of surrounding wild-type crypt cells and drove their differentiation, thereby outcompeting crypt cells from the niche. Genetic or pharmacological inhibition of NOTUM abrogated the ability of Apc-mutant cells to expand and form intestinal adenomas. We identify NOTUM as a key mediator during the early stages of mutation fixation that can be targeted to restore wild-type cell competitiveness and provide preventative strategies for people at a high risk of developing colorectal cancer.
Collapse
Affiliation(s)
| | - Nalle Pentinmikko
- Institute of Biotechnology, HiLIFE, University of Helsinki, Helsinki, Finland
- Molecular and Integrative Bioscience Research Programme, Faculty of Biological and Environmental Sciences, University of Helsinki, Helsinki, Finland
| | - Kalle Luopajärvi
- Institute of Biotechnology, HiLIFE, University of Helsinki, Helsinki, Finland
- Molecular and Integrative Bioscience Research Programme, Faculty of Biological and Environmental Sciences, University of Helsinki, Helsinki, Finland
| | - Nicky J Willis
- Alzheimer's Research UK UCL Drug Discovery Institute, University College London, London, UK
| | - Kathryn Gilroy
- Cancer Research UK Beatson Institute, Glasgow, UK
- SpecifiCancer CRUK Grand Challenge Team (C7932/A29055), Department of Genetics, Harvard Medical School, Boston, MA, USA
| | - Alexander P Raven
- Cancer Research UK Beatson Institute, Glasgow, UK
- SpecifiCancer CRUK Grand Challenge Team (C7932/A29055), Department of Genetics, Harvard Medical School, Boston, MA, USA
| | - Lynn Mcgarry
- Cancer Research UK Beatson Institute, Glasgow, UK
| | - Johanna I Englund
- Institute of Biotechnology, HiLIFE, University of Helsinki, Helsinki, Finland
- Molecular and Integrative Bioscience Research Programme, Faculty of Biological and Environmental Sciences, University of Helsinki, Helsinki, Finland
| | - Anna T Webb
- Department of Cell and Molecular Biology (CMB), Karolinska Institutet, Stockholm, Sweden
| | - Sandra Scharaw
- Department of Cell and Molecular Biology (CMB), Karolinska Institutet, Stockholm, Sweden
| | - Nadia Nasreddin
- Intestinal Stem Cell Biology Lab, Wellcome Trust Centre Human Genetics, University of Oxford, Oxford, UK
| | - Michael C Hodder
- Cancer Research UK Beatson Institute, Glasgow, UK
- Institute of Cancer Sciences, University of Glasgow, Glasgow, UK
| | | | - Emma Minnee
- Cancer Research UK Beatson Institute, Glasgow, UK
- Vrije Universiteit Amsterdam, Amsterdam, The Netherlands
| | | | - Ella Gilchrist
- Cancer Research UK Beatson Institute, Glasgow, UK
- Institute of Cancer Sciences, University of Glasgow, Glasgow, UK
| | | | | | - Christine Perret
- Université de Paris, Institut Cochin, INSERM, CNRS, Paris, France
| | - Ann C Williams
- Colorectal Tumour Biology Group, School of Cellular and Molecular Medicine, Faculty of Life Sciences, University of Bristol, Bristol, UK
| | - Hans Clevers
- SpecifiCancer CRUK Grand Challenge Team (C7932/A29055), Department of Genetics, Harvard Medical School, Boston, MA, USA
- Hubrecht Institute, Royal Netherlands Academy of Arts and Sciences, Utrecht, The Netherlands
| | - Pirjo Nummela
- Department of Pathology, Applied Tumor Genomics, Research Programs Unit and HUSLAB, HUS Diagnostic Center, University of Helsinki and Helsinki University Hospital, Helsinki, Finland
| | - Marianne Lähde
- Translational Cancer Medicine Program, Faculty of Medicine, University of Helsinki, Helsinki, Finland
- Wihuri Research Institute, University of Helsinki, Helsinki, Finland
| | - Kari Alitalo
- Translational Cancer Medicine Program, Faculty of Medicine, University of Helsinki, Helsinki, Finland
- Wihuri Research Institute, University of Helsinki, Helsinki, Finland
| | - Ville Hietakangas
- Institute of Biotechnology, HiLIFE, University of Helsinki, Helsinki, Finland
- Molecular and Integrative Bioscience Research Programme, Faculty of Biological and Environmental Sciences, University of Helsinki, Helsinki, Finland
| | - Ann Hedley
- Cancer Research UK Beatson Institute, Glasgow, UK
| | | | - Colin Nixon
- Cancer Research UK Beatson Institute, Glasgow, UK
| | | | - E Yvonne Jones
- Division of Structural Biology, Wellcome Centre for Human Genetics, University of Oxford, Oxford, UK
| | - Ari Ristimäki
- Department of Pathology, Applied Tumor Genomics, Research Programs Unit and HUSLAB, HUS Diagnostic Center, University of Helsinki and Helsinki University Hospital, Helsinki, Finland
| | - Simon J Leedham
- Intestinal Stem Cell Biology Lab, Wellcome Trust Centre Human Genetics, University of Oxford, Oxford, UK
| | - Paul V Fish
- Alzheimer's Research UK UCL Drug Discovery Institute, University College London, London, UK
- The Francis Crick Institute, London, UK
| | | | - Pekka Katajisto
- Institute of Biotechnology, HiLIFE, University of Helsinki, Helsinki, Finland.
- Molecular and Integrative Bioscience Research Programme, Faculty of Biological and Environmental Sciences, University of Helsinki, Helsinki, Finland.
- Department of Cell and Molecular Biology (CMB), Karolinska Institutet, Stockholm, Sweden.
| | - Owen J Sansom
- Cancer Research UK Beatson Institute, Glasgow, UK.
- SpecifiCancer CRUK Grand Challenge Team (C7932/A29055), Department of Genetics, Harvard Medical School, Boston, MA, USA.
- Institute of Cancer Sciences, University of Glasgow, Glasgow, UK.
| |
Collapse
|
5
|
Abstract
Notum has recently been identified as a negative regulator of Wnt signaling through the removal of an essential palmitoleate group from Wnt proteins. There are emerging reports that Notum plays a role in human disease, with published data suggesting that targeting Notum could represent a new therapeutic approach for treating cancer, osteoporosis and neurodegenerative disorders. Complementary hit-finding strategies have been applied with successful approaches that include high-throughput screening, activity-based protein profiling, screening of fragment libraries and virtual screening campaigns. Structural studies are accelerating the discovery of new inhibitors of Notum. Three fit-for-purpose examples are LP-922056, ABC99 and ARUK3001185. The application of these small-molecule inhibitors is helping to further advance an understanding of the role Notum plays in human disease.
Collapse
Affiliation(s)
- Yuguang Zhao
- Division of Structural Biology, Wellcome Centre for Human Genetics, University of Oxford, Henry Wellcome Building for Genomic Medicine, Roosevelt Drive, Oxford, OX3 7BN, UK
| | - Sarah Jolly
- Alzheimer's Research UK UCL Drug Discovery Institute, University College London, Cruciform Building, Gower Street, London, WC1E 6BT, UK
| | - Stefano Benvegnu
- Alzheimer's Research UK UCL Drug Discovery Institute, University College London, Cruciform Building, Gower Street, London, WC1E 6BT, UK
| | - E Yvonne Jones
- Division of Structural Biology, Wellcome Centre for Human Genetics, University of Oxford, Henry Wellcome Building for Genomic Medicine, Roosevelt Drive, Oxford, OX3 7BN, UK
| | - Paul V Fish
- Alzheimer's Research UK UCL Drug Discovery Institute, University College London, Cruciform Building, Gower Street, London, WC1E 6BT, UK
| |
Collapse
|
6
|
Bayle E, Svensson F, Atkinson BN, Steadman D, Willis NJ, Woodward HL, Whiting P, Vincent JP, Fish PV. Carboxylesterase Notum Is a Druggable Target to Modulate Wnt Signaling. J Med Chem 2021; 64:4289-4311. [PMID: 33783220 PMCID: PMC8172013 DOI: 10.1021/acs.jmedchem.0c01974] [Citation(s) in RCA: 11] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/14/2020] [Indexed: 12/12/2022]
Abstract
Regulation of the Wnt signaling pathway is critically important for a number of cellular processes in both development and adult mammalian biology. This Perspective will provide a summary of current and emerging therapeutic opportunities in modulating Wnt signaling, especially through inhibition of Notum carboxylesterase activity. Notum was recently shown to act as a negative regulator of Wnt signaling through the removal of an essential palmitoleate group. Inhibition of Notum activity may represent a new approach to treat disease where aberrant Notum activity has been identified as the underlying cause. Reliable screening technologies are available to identify inhibitors of Notum, and structural studies are accelerating the discovery of new inhibitors. A selection of these hits have been optimized to give fit-for-purpose small molecule inhibitors of Notum. Three noteworthy examples are LP-922056 (26), ABC99 (27), and ARUK3001185 (28), which are complementary chemical tools for exploring the role of Notum in Wnt signaling.
Collapse
Affiliation(s)
- Elliott
D. Bayle
- Alzheimer’s
Research UK UCL Drug Discovery Institute, University College London, Cruciform Building, Gower Street, London WC1E 6BT, U.K.
- The
Francis Crick Institute, 1 Midland Road, Kings Cross, London NW1 1AT, U.K.
| | - Fredrik Svensson
- Alzheimer’s
Research UK UCL Drug Discovery Institute, University College London, Cruciform Building, Gower Street, London WC1E 6BT, U.K.
- The
Francis Crick Institute, 1 Midland Road, Kings Cross, London NW1 1AT, U.K.
| | - Benjamin N. Atkinson
- Alzheimer’s
Research UK UCL Drug Discovery Institute, University College London, Cruciform Building, Gower Street, London WC1E 6BT, U.K.
| | - David Steadman
- Alzheimer’s
Research UK UCL Drug Discovery Institute, University College London, Cruciform Building, Gower Street, London WC1E 6BT, U.K.
| | - Nicky J. Willis
- Alzheimer’s
Research UK UCL Drug Discovery Institute, University College London, Cruciform Building, Gower Street, London WC1E 6BT, U.K.
| | - Hannah L. Woodward
- Alzheimer’s
Research UK UCL Drug Discovery Institute, University College London, Cruciform Building, Gower Street, London WC1E 6BT, U.K.
| | - Paul Whiting
- Alzheimer’s
Research UK UCL Drug Discovery Institute, University College London, Cruciform Building, Gower Street, London WC1E 6BT, U.K.
| | - Jean-Paul Vincent
- The
Francis Crick Institute, 1 Midland Road, Kings Cross, London NW1 1AT, U.K.
| | - Paul V. Fish
- Alzheimer’s
Research UK UCL Drug Discovery Institute, University College London, Cruciform Building, Gower Street, London WC1E 6BT, U.K.
- The
Francis Crick Institute, 1 Midland Road, Kings Cross, London NW1 1AT, U.K.
| |
Collapse
|
7
|
Mahy W, Willis NJ, Zhao Y, Woodward HL, Svensson F, Sipthorp J, Vecchia L, Ruza RR, Hillier J, Kjær S, Frew S, Monaghan A, Bictash M, Salinas PC, Whiting P, Vincent JP, Jones EY, Fish PV. 5-Phenyl-1,3,4-oxadiazol-2(3 H)-ones Are Potent Inhibitors of Notum Carboxylesterase Activity Identified by the Optimization of a Crystallographic Fragment Screening Hit. J Med Chem 2020; 63:12942-12956. [PMID: 33124429 DOI: 10.1021/acs.jmedchem.0c01391] [Citation(s) in RCA: 9] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/06/2023]
Abstract
Carboxylesterase Notum is a negative regulator of the Wnt signaling pathway. There is an emerging understanding of the role Notum plays in disease, supporting the need to discover new small-molecule inhibitors. A crystallographic X-ray fragment screen was performed, which identified fragment hit 1,2,3-triazole 7 as an attractive starting point for a structure-based drug design hit-to-lead program. Optimization of 7 identified oxadiazol-2-one 23dd as a preferred example with properties consistent with drug-like chemical space. Screening 23dd in a cell-based TCF/LEF reporter gene assay restored the activation of Wnt signaling in the presence of Notum. Mouse pharmacokinetic studies with oral administration of 23dd demonstrated good plasma exposure and partial blood-brain barrier penetration. Significant progress was made in developing fragment hit 7 into lead 23dd (>600-fold increase in activity), making it suitable as a new chemical tool for exploring the role of Notum-mediated regulation of Wnt signaling.
Collapse
Affiliation(s)
- William Mahy
- Alzheimer's Research UK UCL Drug Discovery Institute, University College London, Cruciform Building, Gower Street, London WC1E 6BT, U.K
| | - Nicky J Willis
- Alzheimer's Research UK UCL Drug Discovery Institute, University College London, Cruciform Building, Gower Street, London WC1E 6BT, U.K
| | - Yuguang Zhao
- Division of Structural Biology, Wellcome Centre for Human Genetics, University of Oxford, The Henry Wellcome Building for Genomic Medicine, Roosevelt Drive, Oxford OX3 7BN, U.K
| | - Hannah L Woodward
- Alzheimer's Research UK UCL Drug Discovery Institute, University College London, Cruciform Building, Gower Street, London WC1E 6BT, U.K
| | - Fredrik Svensson
- Alzheimer's Research UK UCL Drug Discovery Institute, University College London, Cruciform Building, Gower Street, London WC1E 6BT, U.K
- The Francis Crick Institute, 1 Midland Road, Kings Cross, London NW1 1AT, U.K
| | - James Sipthorp
- Alzheimer's Research UK UCL Drug Discovery Institute, University College London, Cruciform Building, Gower Street, London WC1E 6BT, U.K
- The Francis Crick Institute, 1 Midland Road, Kings Cross, London NW1 1AT, U.K
| | - Luca Vecchia
- Division of Structural Biology, Wellcome Centre for Human Genetics, University of Oxford, The Henry Wellcome Building for Genomic Medicine, Roosevelt Drive, Oxford OX3 7BN, U.K
| | - Reinis R Ruza
- Division of Structural Biology, Wellcome Centre for Human Genetics, University of Oxford, The Henry Wellcome Building for Genomic Medicine, Roosevelt Drive, Oxford OX3 7BN, U.K
| | - James Hillier
- Division of Structural Biology, Wellcome Centre for Human Genetics, University of Oxford, The Henry Wellcome Building for Genomic Medicine, Roosevelt Drive, Oxford OX3 7BN, U.K
| | - Svend Kjær
- The Francis Crick Institute, 1 Midland Road, Kings Cross, London NW1 1AT, U.K
| | - Sarah Frew
- Alzheimer's Research UK UCL Drug Discovery Institute, University College London, Cruciform Building, Gower Street, London WC1E 6BT, U.K
| | - Amy Monaghan
- Alzheimer's Research UK UCL Drug Discovery Institute, University College London, Cruciform Building, Gower Street, London WC1E 6BT, U.K
| | - Magda Bictash
- Alzheimer's Research UK UCL Drug Discovery Institute, University College London, Cruciform Building, Gower Street, London WC1E 6BT, U.K
| | - Patricia C Salinas
- Department of Cell and Developmental Biology, Laboratory for Molecular and Cellular Biology, University College London, London WC1E 6BT, U.K
| | - Paul Whiting
- Alzheimer's Research UK UCL Drug Discovery Institute, University College London, Cruciform Building, Gower Street, London WC1E 6BT, U.K
| | - Jean-Paul Vincent
- The Francis Crick Institute, 1 Midland Road, Kings Cross, London NW1 1AT, U.K
| | - E Yvonne Jones
- Division of Structural Biology, Wellcome Centre for Human Genetics, University of Oxford, The Henry Wellcome Building for Genomic Medicine, Roosevelt Drive, Oxford OX3 7BN, U.K
| | - Paul V Fish
- Alzheimer's Research UK UCL Drug Discovery Institute, University College London, Cruciform Building, Gower Street, London WC1E 6BT, U.K
- The Francis Crick Institute, 1 Midland Road, Kings Cross, London NW1 1AT, U.K
| |
Collapse
|
8
|
Abstract
Notum inhibits Wnt signalling via enzymatic delipidation of Wnt ligands. Restoration of Wnt signalling by small molecule inhibition of Notum may be of therapeutic benefit in a number of pathologies including Alzheimer's disease. Here we report Notum activity can be inhibited by caffeine (IC50 19 µM), but not by demethylated caffeine metabolites: paraxanthine, theobromine and theophylline. Cellular luciferase assays show Notum-suppressed Wnt3a function can be restored by caffeine with an EC50 of 46 µM. The dissociation constant (Kd) between Notum and caffeine is 85 µM as measured by surface plasmon resonance. High-resolution crystal structures of Notum complexes with caffeine and its minor metabolite theophylline show both compounds bind at the centre of the enzymatic pocket, overlapping the position of the natural substrate palmitoleic lipid, but using different binding modes. The structural information reported here may be of relevance for the design of more potent brain-accessible Notum inhibitors.
Collapse
Affiliation(s)
- Yuguang Zhao
- Division of Structural Biology, Wellcome Centre for Human Genetics, University of Oxford, Oxford, OX3 7BN, UK.
| | - Jingshan Ren
- Division of Structural Biology, Wellcome Centre for Human Genetics, University of Oxford, Oxford, OX3 7BN, UK
| | - James Hillier
- Division of Structural Biology, Wellcome Centre for Human Genetics, University of Oxford, Oxford, OX3 7BN, UK
| | - Weixian Lu
- Division of Structural Biology, Wellcome Centre for Human Genetics, University of Oxford, Oxford, OX3 7BN, UK
| | - Edith Yvonne Jones
- Division of Structural Biology, Wellcome Centre for Human Genetics, University of Oxford, Oxford, OX3 7BN, UK.
| |
Collapse
|
9
|
Stehlin F, Ribi C. [Hereditary angioedema due to C1-esterase inhibitor deficiency : novel approaches]. Rev Med Suisse 2020; 16:675-678. [PMID: 32270933] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 06/11/2023]
Abstract
Hereditary angioedema type 1 and 2 are due to a deficiency in C1--esterase inhibitor. This molecule inhibits the generation of bradykinin, a potent inflammatory mediator that increases vascular permeability. Upon accumulation of bradykinin, patients affected develop painful subcutaneous or submucosal edemas that last for several days. In case the upper airways are affected, there is risk of suffocation. This type of angioedema does not respond to antihistamines, cortico-steroids or epinephrine. Management of angioedema attacks consists in injecting C1-esterase inhibitor concentrate or icatibant, a bradykinin receptor B2 antagonist. Preventive measures aim at reducing the frequency and the severity of angioedema attacks. Inhibition of -plasma kallikrein by lanadelumab, a monoclonal antibody adminis-tered subcutaneously, is effective and well tolerated.
Collapse
Affiliation(s)
| | - Camillo Ribi
- Service d'immunologie et allergie, CHUV, 1011 Lausanne
| |
Collapse
|
10
|
Zhao Y, Ren J, Hillier J, Jones M, Lu W, Jones EY. Structural characterization of melatonin as an inhibitor of the Wnt deacylase Notum. J Pineal Res 2020; 68:e12630. [PMID: 31876313 PMCID: PMC7027535 DOI: 10.1111/jpi.12630] [Citation(s) in RCA: 15] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 10/17/2019] [Revised: 12/18/2019] [Accepted: 12/20/2019] [Indexed: 12/21/2022]
Abstract
The hormone melatonin, secreted from the pineal gland, mediates multiple physiological effects including modulation of Wnt/β-catenin signalling. The Wnt palmitoleate lipid modification is essential for its signalling activity, while the carboxylesterase Notum can remove the lipid from Wnt and inactivate it. Notum enzyme inhibition can therefore upregulate Wnt signalling. While searching for Notum inhibitors by crystallographic fragment screening, a hit compound N-[2-(5-fluoro-1H-indol-3-yl)ethyl]acetamide that is structurally similar to melatonin came to our attention. We then soaked melatonin and its precursor N-acetylserotonin into Notum crystals and obtained high-resolution structures (≤1.5 Å) of their complexes. In each of the structures, two compound molecules bind with Notum: one at the enzyme's catalytic pocket, overlapping the space occupied by the acyl tail of the Wnt palmitoleate lipid, and the other at the edge of the pocket opposite the substrate entrance. Although the inhibitory activity of melatonin shown by in vitro enzyme assays is low (IC50 75 µmol/L), the structural information reported here provides a basis for the design of potent and brain accessible drugs for neurodegenerative diseases such as Alzheimer's disease, in which upregulation of Wnt signalling may be beneficial.
Collapse
Affiliation(s)
- Yuguang Zhao
- Division of Structural BiologyWellcome Centre for Human GeneticsUniversity of OxfordOxfordUK
| | - Jingshan Ren
- Division of Structural BiologyWellcome Centre for Human GeneticsUniversity of OxfordOxfordUK
| | - James Hillier
- Division of Structural BiologyWellcome Centre for Human GeneticsUniversity of OxfordOxfordUK
| | - Margaret Jones
- Division of Structural BiologyWellcome Centre for Human GeneticsUniversity of OxfordOxfordUK
| | - Weixian Lu
- Division of Structural BiologyWellcome Centre for Human GeneticsUniversity of OxfordOxfordUK
| | - Edith Yvonne Jones
- Division of Structural BiologyWellcome Centre for Human GeneticsUniversity of OxfordOxfordUK
| |
Collapse
|
11
|
Zhao W, Zheng Z, Zhang J, Roger SF, Luo X. Allelopathically inhibitory effects of eucalyptus extracts on the growth of Microcystis aeruginosa. Chemosphere 2019; 225:424-433. [PMID: 30889406 DOI: 10.1016/j.chemosphere.2019.03.070] [Citation(s) in RCA: 26] [Impact Index Per Article: 5.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/27/2018] [Revised: 03/04/2019] [Accepted: 03/11/2019] [Indexed: 06/09/2023]
Abstract
Microcystis aeruginosa (M. aeruginosa), as the dominant algae in eutrophic water bodies, has caused a serious harm to the local eco-environment. A biological tool, employing allelopathic inhibitory of eucalyptus to control M. aeruginosa, has been receiving tremendous attention. This work presents the results of the allelopathic inhibitory effects of eucalyptus (Eucalyptus grandis × E.urophylla 'GLGU9') extracts of roots (ERE), stems (ESE), and leaves (ELE) on culture solutions of M. aeruginosa and its eco-physiological mechanism. The inhibitory effects of the extracts on the growth of M. aeruginosa varied greatly with ELE exhibiting the highest level of potency. Modes of action by which ELE inhibited M. aeruginosa growth were established. They involved reduction in photosynthesis, disruption of the cell membrane integrity, and inhibition of esterase activities of the cyanobacterial cells. However, ELE did not exhibit any gradients of toxicity towards zebrafish nor Washington grass plant. Species abundance and diversity in the systems remained likewise unaffected by ELE. The synergistic interaction between ELE and single-component allelochemicals (e.g., gallic acid and berberine) was ascribed to the increase in efficacy of allelochemicals in the various systems. The results of this study provide an underlying, novel, and attractive approach for controlling the growth of M. aeruginosa in aquatic environments.
Collapse
Affiliation(s)
- Wei Zhao
- Department of Environmental Science and Engineering, Fudan University, Shanghai, 200433, PR China
| | - Zheng Zheng
- Department of Environmental Science and Engineering, Fudan University, Shanghai, 200433, PR China.
| | - JunLei Zhang
- Department of Environmental Science and Engineering, Fudan University, Shanghai, 200433, PR China
| | - Saint-Fort Roger
- Department of Environmental Science, Mount Royal University, Calgary, AB, T3E 6K6, Canada
| | - XingZhang Luo
- Department of Environmental Science and Engineering, Fudan University, Shanghai, 200433, PR China
| |
Collapse
|
12
|
Panini M, Tozzi F, Zimmer CT, Bass C, Field L, Borzatta V, Mazzoni E, Moores G. Biochemical evaluation of interactions between synergistic molecules and phase I enzymes involved in insecticide resistance in B- and Q-type Bemisia tabaci (Hemiptera: Aleyrodidae). Pest Manag Sci 2017; 73:1873-1882. [PMID: 28195678 DOI: 10.1002/ps.4553] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/09/2016] [Revised: 01/20/2017] [Accepted: 02/08/2017] [Indexed: 06/06/2023]
Abstract
BACKGROUND Metabolic resistance is an important consideration in the whitefly Bemisia tabaci, where an esterase-based mechanism has been attributed to pyrethroid resistance and over-expression of the cytochrome P450, CYP6CM1, has been correlated to resistance to imidacloprid and other neonicotinoids. RESULTS In vitro interactions between putative synergists and CYP6CM1, B and Q-type esterases were investigated, and structure-activity relationship analyses allowed the identification of chemical structures capable of acting as inhibitors of esterase and oxidase activities. Specifically, methylenedioxyphenyl (MDP) moieties with a polyether chain were preferable for optimum inhibition of B-type esterase, whilst corresponding dihydrobenzofuran structures were potent for the Q-esterase variation. Potent inhibition of CYP6CM1 resulted from structures which contained an alkynyl chain with a terminal methyl group. CONCLUSIONS Synergist candidates could be considered for field control of B. tabaci, especially to abrogate neonicotinoid resistance. © 2017 Society of Chemical Industry.
Collapse
Affiliation(s)
- Michela Panini
- ApresLabs Ltd, Harpenden, Herts, UK
- Dipartimento di Scienze delle Produzioni Vegetali Sostenibili, Università Cattolica del Sacro Cuore, Piacenza, Italy
| | | | - Christoph T Zimmer
- College of Life and Environmental Sciences, University of Exeter, Penryn, Cornwall, UK
- Department of Biological Chemistry and Crop Protection, Rothamsted Research, Harpenden, Herts, UK
| | - Chris Bass
- College of Life and Environmental Sciences, University of Exeter, Penryn, Cornwall, UK
- Department of Biological Chemistry and Crop Protection, Rothamsted Research, Harpenden, Herts, UK
| | - Linda Field
- Department of Biological Chemistry and Crop Protection, Rothamsted Research, Harpenden, Herts, UK
| | | | - Emanuele Mazzoni
- Dipartimento di Scienze delle Produzioni Vegetali Sostenibili, Università Cattolica del Sacro Cuore, Piacenza, Italy
| | | |
Collapse
|
13
|
Panini M, Tozzi F, Bass C, Zimmer CT, Field L, Borzatta V, Mazzoni E, Moores G. The interactions of piperonyl butoxide and analogues with the metabolic enzymes FE4 and CYP6CY3 of the green peach aphid Myzus persicae (Hemiptera: Aphididae). Pest Manag Sci 2017; 73:371-379. [PMID: 27174317 DOI: 10.1002/ps.4314] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/21/2015] [Revised: 05/09/2016] [Accepted: 05/09/2016] [Indexed: 06/05/2023]
Abstract
BACKGROUND Piperonyl butoxide (PBO) is a well-known insecticide synergist capable of interacting with phase 1 metabolic enzymes, specifically esterases and cytochrome P450s. In this study, structure-activity relationship analyses were used to characterise the interaction of around 30 analogues of PBO with the esterase FE4 and the P450 CYP6CY3 from insecticide-resistant Myzus persicae (Sulzer), in order to predict the synthesis of more potent inhibitors. RESULTS Enzyme inhibition studies were performed against esterase and oxidase activities and, together with in silico modelling, key activity determinants of the analogues were identified and optimised. Novel analogues were then designed and synthesised, some of which showed greater inhibition against both enzymatic systems: specifically, dihydrobenzofuran moieties containing an alkynyl side chain and a butyl side chain against FE4, and benzodioxole derivatives with a propyl/butyl side chain and an alkynyl ether moiety for CYP6CY3. CONCLUSIONS In vitro assays identified potential candidate synergists with high inhibitory potency. The in vivo confirmation of such results will allow consideration for a possible use in agriculture. © 2016 Society of Chemical Industry.
Collapse
Affiliation(s)
- Michela Panini
- ApresLabs Ltd, Harpenden, Herts, UK
- Dipartimento di Scienze delle Produzioni Vegetali Sostenibili, Università Cattolica del Sacro Cuore, Piacenza, Italy
| | | | - Chris Bass
- Rothamsted Research, Harpenden, Herts, UK
| | | | | | | | - Emanuele Mazzoni
- Dipartimento di Scienze delle Produzioni Vegetali Sostenibili, Università Cattolica del Sacro Cuore, Piacenza, Italy
| | | |
Collapse
|
14
|
Mansoor MM, Raza ABM, Abbas N, Aqueel MA, Afzal M. Resistance of green lacewing, Chrysoperla carnea Stephens to nitenpyram: Cross-resistance patterns, mechanism, stability, and realized heritability. Pestic Biochem Physiol 2017; 135:59-63. [PMID: 28043332 DOI: 10.1016/j.pestbp.2016.06.004] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/21/2016] [Revised: 04/12/2016] [Accepted: 06/18/2016] [Indexed: 06/06/2023]
Abstract
The green lacewing, Chrysoperla carnea Stephens (Neuroptera: Chrysopidae) is a major generalist predator employed in integrated pest management (IPM) plans for pest control on many crops. Nitenpyram, a neonicotinoid insecticide has widely been used against the sucking pests of cotton in Pakistan. Therefore, a field green lacewing strain was exposed to nitenpyram for five generations to investigate resistance evolution, cross-resistance pattern, stability, realized heritability, and mechanisms of resistance. Before starting the selection with nitenpyram, a field collected strain showed 22.08-, 23.09-, 484.69- and 602.90-fold resistance to nitenpyram, buprofezin, spinosad and acetamiprid, respectively compared with the Susceptible strain. After continuous selection for five generations (G1-G5) with nitenpyram in the laboratory, the Field strain (Niten-SEL) developed a resistance ratio of 423.95 at G6. The Niten-SEL strain at G6 showed no cross-resistance to buprofezin and acetamiprid and negative cross-resistance to spinosad compared with the Field strain (G1). For resistance stability, the Niten-SEL strain was left unexposed to any insecticide for four generations (G6-G9) and bioassay results at G10 showed that resistance to nitenpyram, buprofezin and spinosad was stable, while resistance to acetamiprid was unstable. The realized heritability values were 0.97, 0.16, 0.03, and -0.16 to nitenpyram, buprofezin, acetamiprid and spinosad, respectively, after five generations of selection. Moreover, the enzyme inhibitors (PBO or DEF) significantly decreased the nitenpyram resistance in the resistant strain, suggesting that resistance was due to microsomal oxidases and esterases. These results are very helpful for integration of green lacewings in IPM programs.
Collapse
Affiliation(s)
- Muhammad Mudassir Mansoor
- Department of Entomology, University College of Agriculture, University of Sargodha, Sargodha, Pakistan.
| | - Abu Bakar Muhammad Raza
- Department of Entomology, University College of Agriculture, University of Sargodha, Sargodha, Pakistan
| | - Naeem Abbas
- Department of Entomology, University College of Agriculture and Environmental Sciences, Islamia University of Bahawalpur, Bahawalpur, Pakistan
| | - Muhammad Anjum Aqueel
- Department of Entomology, University College of Agriculture, University of Sargodha, Sargodha, Pakistan
| | - Muhammad Afzal
- Department of Entomology, University College of Agriculture, University of Sargodha, Sargodha, Pakistan
| |
Collapse
|
15
|
Tak JH, Isman MB. Metabolism of citral, the major constituent of lemongrass oil, in the cabbage looper, Trichoplusia ni, and effects of enzyme inhibitors on toxicity and metabolism. Pestic Biochem Physiol 2016; 133:20-25. [PMID: 27742357 DOI: 10.1016/j.pestbp.2016.03.009] [Citation(s) in RCA: 39] [Impact Index Per Article: 4.9] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/08/2016] [Revised: 03/17/2016] [Accepted: 03/23/2016] [Indexed: 05/23/2023]
Abstract
Although screening for new and reliable sources of botanical insecticides remains important, finding ways to improve the efficacy of those already in use through better understanding of their modes-of-action or metabolic pathways, or by improving formulations, deserves greater attention as the latter may present lesser regulation hurdles. Metabolic processing of citral (a combination of the stereoisomers geranial and neral), a main constituent of lemongrass (Cymbopogon citratus) essential oil has not been previously examined in insects. To address this, we investigated insecticidal activities of lemongrass oil and citral, as well as the metabolism of citral in larvae of the cabbage looper, Trichoplusia ni, in associations with well-known enzyme inhibitors. Among the inhibitors tested, piperonyl butoxide showed the highest increase in toxicity followed by triphenyl phosphate, but no synergistic interaction between the inhibitors was observed. Topical application of citral to fifth instar larvae produced mild reductions in food consumption, and frass analysis after 24h revealed geranic acid (99.7%) and neric acid (98.8%) as major metabolites of citral. Neither citral nor any other metabolites were found following in vivo analysis of larvae after 24h, and no significant effect of enzyme inhibitors was observed on diet consumption or citral metabolism.
Collapse
Affiliation(s)
- Jun-Hyung Tak
- Faculty of Land and Food Systems, University of British Columbia, Vancouver, British Columbia V6T 1Z4, Canada.
| | - Murray B Isman
- Faculty of Land and Food Systems, University of British Columbia, Vancouver, British Columbia V6T 1Z4, Canada.
| |
Collapse
|
16
|
Ullah S, Shah RM, Shad SA. Genetics, realized heritability and possible mechanism of chlorfenapyr resistance in Oxycarenus hyalinipennis (Lygaeidae: Hemiptera). Pestic Biochem Physiol 2016; 133:91-96. [PMID: 27742367 DOI: 10.1016/j.pestbp.2016.02.007] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/19/2015] [Revised: 02/17/2016] [Accepted: 02/20/2016] [Indexed: 06/06/2023]
Abstract
Dusky cotton bug (DCB), Oxycarenus hyalinipennis (Lygaeidae: Hemiptera) is a serious pest of cotton and other malvaceous plants. Chlorfenapyr, a broad spectrum, N-substituted, halogenated pyrrole insecticide is used extensively to control many insect pests in cotton, including DCB. In this study, we investigated a field strain of DCB to assess its potential to develop resistance to chlorfenapyr. After six generations of continuous selection pressure with chlorfenapyr, DCB had a 7.24-fold and 149.06-fold resistance ratio (RR) at G1 and G6, respectively. The genetic basis of inheritance of chlorfenapyr resistance was also studied by crossing the chlorfenapyr selected (Chlorfenapyr-SEL) and laboratory population (Lab-PK). Results revealed an autosomal and incompletely dominant mode of inheritance for chlorfenapyr resistance in the Chlorfenapyr-SEL population of DCB. The results of the monogenic model test showed chlorfenapyr resistance was controlled by multiple genes. Estimated realized heritability for chlorfenapyr resistance in the tested DCB strain was 0.123. Synergism bioassays with piperonyl butoxide and S, S, S-butyl phosphorotrithioate revealed chlorfenapyr resistance might be due to esterase activity. These results would be useful for devising an effective resistance management strategy against DCB.
Collapse
Affiliation(s)
- Saif Ullah
- Department of Entomology, Faculty of Agricultural Sciences and Technology, Bahauddin Zakariya University, Multan, Punjab, Pakistan.
| | - Rizwan Mustafa Shah
- Department of Entomology, Faculty of Agricultural Sciences and Technology, Bahauddin Zakariya University, Multan, Punjab, Pakistan.
| | - Sarfraz Ali Shad
- Department of Entomology, Faculty of Agricultural Sciences and Technology, Bahauddin Zakariya University, Multan, Punjab, Pakistan.
| |
Collapse
|
17
|
Ratnatilaka Na Bhuket P, Niwattisaiwong N, Limpikirati P, Khemawoot P, Towiwat P, Ongpipattanakul B, Rojsitthisak P. Simultaneous determination of curcumin diethyl disuccinate and its active metabolite curcumin in rat plasma by LC-MS/MS: Application of esterase inhibitors in the stabilization of an ester-containing prodrug. J Chromatogr B Analyt Technol Biomed Life Sci 2016; 1033-1034:301-310. [PMID: 27595650 DOI: 10.1016/j.jchromb.2016.08.039] [Citation(s) in RCA: 25] [Impact Index Per Article: 3.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/31/2016] [Revised: 08/22/2016] [Accepted: 08/26/2016] [Indexed: 11/17/2022]
Abstract
Four esterase inhibitors, ethylenediamine tetraacetic acid disodium (Na2EDTA), sodium fluoride (NaF), bis(4-nitrophenyl) phosphate (BNPP) and phenylmethanesulfonyl fluoride (PMSF), were evaluated for their inhibitory effects on enzymatic hydrolysis of labile phenolate esters in curcumin diethyl disuccinate (CDD), a prodrug of curcumin (CUR), in rat plasma. BNPP and PMSF at 10mM exhibited stabilization by preventing degradation of CDD. BNPP at a final concentration of 10mM was subsequently selected to prevent ex vivo metabolism of CDD throughout LC-MS/MS analysis of CDD and CUR in rat plasma. A simple protein precipitation technique using acetonitrile as a precipitating agent was used to extract CDD, CUR and dimethylcurcumin (DMC), an internal standard, from rat plasma. Chromatographic separation was performed on a Halo C8 column (4.6×50mm, 2.7μm) using an isocratic mobile phase containing acetonitrile-0.2% formic acid in water (73:27v/v) with a flow rate of 0.4mLmin(-1). An AB SCIEX QTRAP(®) 6500 mass spectrometer was operated using a positive ion electrospray mode for ionization and detection of analytes and internal standard. Calibration curves for CDD and CUR were established using 50μL of rat plasma over the concentration range of 1-500ngmL(-1). The developed method was fully validated according to US Food and Drug Administration (FDA) guidelines for selectivity, sensitivity, linearity, accuracy, precision, dilution integrity, recovery, matrix effect, and stability. The validated method was applied to evaluate the pharmacokinetics of CDD and CUR in rats after a single intravenous dose of 40mgkg(-1). The method using BNPP as an esterase inhibitor was successful in determining the remaining CDD in rat plasma. The pharmacokinetic results indicate that CDD in rats is converted instantaneously to CUR after intravenous administration and a higher CUR plasma concentration at 5min is achieved in comparison with direct intravenous injection of CUR.
Collapse
Affiliation(s)
- Pahweenvaj Ratnatilaka Na Bhuket
- Biomedicinal Chemistry Program, Faculty of Pharmaceutical Sciences, Chulalongkorn University, 254 Phayathai Road, Patumwan, Bangkok, 10330, Thailand
| | - Nuansri Niwattisaiwong
- Department of Food and Pharmaceutical Chemistry, Faculty of Pharmaceutical Sciences, Chulalongkorn University, 254 Phayathai Road, Patumwan, Bangkok, 10330, Thailand; School of Pharmacy, Eastern Asia University, 200 Rangsit-Nakhon Nayok Road (Klong5), Thanyaburi, Pathum Thani, 12110, Thailand
| | - Patanachai Limpikirati
- Department of Food and Pharmaceutical Chemistry, Faculty of Pharmaceutical Sciences, Chulalongkorn University, 254 Phayathai Road, Patumwan, Bangkok, 10330, Thailand
| | - Phisit Khemawoot
- Department of Pharmacology and Physiology, Faculty of Pharmaceutical Sciences, Chulalongkorn University, 254 Phayathai Road, Patumwan, Bangkok, 10330, Thailand
| | - Pasarapa Towiwat
- Department of Pharmacology and Physiology, Faculty of Pharmaceutical Sciences, Chulalongkorn University, 254 Phayathai Road, Patumwan, Bangkok, 10330, Thailand
| | - Boonsri Ongpipattanakul
- Department of Biochemistry and Microbiology, Faculty of Pharmaceutical Sciences, Chulalongkorn University, 254 Phayathai Road, Patumwan, Bangkok, 10330, Thailand; Chulalongkorn University Drug and Health Products Innovation & Promotion Center, Faculty of Pharmaceutical Sciences, Chulalongkorn University, 254 Phayathai Road, Patumwan, Bangkok, 10330, Thailand
| | - Pornchai Rojsitthisak
- Department of Food and Pharmaceutical Chemistry, Faculty of Pharmaceutical Sciences, Chulalongkorn University, 254 Phayathai Road, Patumwan, Bangkok, 10330, Thailand.
| |
Collapse
|
18
|
Yeom HJ, Jung CS, Kang J, Kim J, Lee JH, Kim DS, Kim HS, Park PS, Kang KS, Park IK. Insecticidal and acetylcholine esterase inhibition activity of Asteraceae plant essential oils and their constituents against adults of the German cockroach (Blattella germanica). J Agric Food Chem 2015; 63:2241-2248. [PMID: 25664467 DOI: 10.1021/jf505927n] [Citation(s) in RCA: 34] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/04/2023]
Abstract
The fumigant and contact toxicities of 16 Asteraceae plant essential oils and their constituents against adult male and female Blattella germanica were examined. In a fumigant toxicity test, tarragon oil exhibited 100% and 90% fumigant toxicity against adult male German cockroaches at 5 and 2.5 mg/filter paper, respectively. Fumigant toxicities of Artemisia arborescens and santolina oils against adult male German cockroaches were 100% at 20 mg/filter paper, but were reduced to 60% and 22.5% at 10 mg/filter paper, respectively. In contact toxicity tests, tarragon and santolina oils showed potent insecticidal activity against adult male German cockroaches. Components of active oils were analyzed using gas chromatography, gas chromatography-mass spectrometry, or nuclear magnetic resonance spectrometer. Among the identified compounds from active essential oils, estragole demonstrated potent fumigant and contact toxicity against adult German cockroaches. β-Phellandrene exhibited inhibition of male and female German cockroach acetylcholinesterase activity with IC50 values of 0.30 and 0.28 mg/mL, respectively.
Collapse
Affiliation(s)
- Hwa-Jeong Yeom
- Division of Forest Insect Pests and Diseases, Korea Forest Research Institute , Seoul 130-712, Republic of Korea
| | | | | | | | | | | | | | | | | | | |
Collapse
|
19
|
Adachi S, Cognetta AB, Niphakis MJ, He Z, Zajdlik A, St Denis JD, Scully CCG, Cravatt BF, Yudin AK. Facile synthesis of borofragments and their evaluation in activity-based protein profiling. Chem Commun (Camb) 2015; 51:3608-11. [PMID: 25633248 PMCID: PMC4330092 DOI: 10.1039/c4cc09107h] [Citation(s) in RCA: 23] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/29/2022]
Abstract
The discovery of enzyme inhibitors relies on synthetic methods that enable rapid and modular construction of small molecules. Heterocyclic fragments designed to maximize enthalpic interactions with their protein targets represent a particularly desirable class of molecules. Here we describe a reagent that enables straightforward construction of "borofragments", in which a heterocycle is separated from the boron center by two or three rotatable bonds. The stability of these molecules depends on the MIDA group which likely acts as a slow-release element under biological conditions. Borofragments can be used to discover inhibitors of enzymes that use catalytic oxygen nucleophiles. We have employed this method to identify inhibitors of ABHD10 and the predicted carboxypeptidase CPVL. This technique should be applicable to other classes of targets.
Collapse
Affiliation(s)
- Shinya Adachi
- Davenport Research Laboratories, Department of Chemistry, University of Toronto, 80 St. George St., Toronto, ON M5S3H6, Canada.
| | | | | | | | | | | | | | | | | |
Collapse
|
20
|
Delhanty PJD, Huisman M, Julien M, Mouchain K, Brune P, Themmen APN, Abribat T, van der Lely AJ. The acylated (AG) to unacylated (UAG) ghrelin ratio in esterase inhibitor-treated blood is higher than previously described. Clin Endocrinol (Oxf) 2015; 82:142-6. [PMID: 24810977 DOI: 10.1111/cen.12489] [Citation(s) in RCA: 35] [Impact Index Per Article: 3.9] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 02/26/2014] [Revised: 04/11/2014] [Accepted: 05/01/2014] [Indexed: 01/13/2023]
Abstract
CONTEXT The acylated/unacylated ghrelin (AG/UAG) ratio has been reported to range from 0·02 to 0·3, suggesting biologically relevant independent regulation of each ghrelin isoform. However, AG is deacylated to UAG by esterases in blood samples, and esterase inhibition is critical for their accurate measurement. Our hypothesis is that at least part of the variation in reported AG and UAG values is due to inconsistent sample preparation. DESIGN A non-interventional study. Quantification with two different, commercially available, ELISA formats of AG and UAG in venous plasma stabilized or not with 4-(2-aminoethyl) benzenesulphonyl fluoride (AEBSF) and stored for 0-6 months at -20 or -80 °C. PARTICIPANTS Healthy, non-obese, adults (n = 8; 4 women), age 26-42 yrs, after an overnight fast. MEASUREMENTS AG and UAG stability following different methods of sample treatment and storage. RESULTS Non-AEBSF plasma contained low AG and high UAG (>270 pg/ml) indicating rapid conversion of AG to UAG. However, AEBSF plasma, stored at -80 °C and measured at 0, 1, 3 and 6 months contained AG and UAG ranges of 12-350 and 17-170 pg/ml, respectively. Mean (SEM) AG/UAG ratios were 1·7(0·3), 1·2(0·2), 1·5(0·3) and 1·8(0·5) at each time point with no significant effect of storage period. CONCLUSIONS AG and UAG levels measured in AEBSF-stabilized plasma indicate that the AG/UAG ratio is markedly higher than previously described and that UAG is a physiological component of the circulation. This highlights the importance of immediately stabilizing blood samples on collection for determination of both AG and UAG concentrations and provides a valuable tool for their measurement in physiological and interventional studies.
Collapse
|
21
|
Muthusamy R, Shivakumar MS. Effect of lambda cyhalothrin and temephos on detoxification enzyme systems in Culex quinquefasciatus (Diptera: Culicidae). J Environ Biol 2015; 36:235-239. [PMID: 26536798] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 06/05/2023]
Abstract
Mosquitoes serve as vector for transmitting diseases. Among mosquitoes, Culex quinquefasciatus transmits lymphatic filariasis, yellow fever Japanese encephalitis etc. Application of chemical insecticides is still the best option for vector control programmes. Continuous use of these chemicals on mosquito reduces its effects. The present study determined the baseline susceptibility of Cx. quinquefasciatus in response to λ-cyhalothrin and temephos treatments. In addition, the biochemical mechanisms and zymogram analysis involved in insecticide detoxification among larval mosquitoes were studied. The larval bioassay indicated high LC50 value for λ-cyhalothrin (0.1484ppm) as compared to temephos (0.01092ppm). While AChE assay showed increased activity in temephos treatments, glutathione reductase (GR) and esterase levels were increased at both the treatments. Esterase quantitative analysis revealed the expression of three bands at 43kDa, 67kDa and 245kDa. The findings suggest that insensitivity of AChE, esterase and high GR activity may play an important role in developing resistance to synthetic pyrethroid and organophosphate insecticides in Cx. quinquefasciatus population.
Collapse
|
22
|
Abstract
Prodrugs are effective tools in overcoming drawbacks typically associated with drug formulation and delivery. Those employing esterase-triggered functional groups are frequently utilized to mask polar carboxylic acids and phenols, increasing drug-like properties such as lipophilicity. Herein we detail a comprehensive assessment for strategies that effectively release hydroxy and phenolic moieties in the presence of an esterase. Matrix metalloproteinases (MMPs) serve as our proof-of-concept target. Three distinct ester-responsive protecting groups are incorporated into MMP proinhibitors containing hydroxy moieties. Analytical evaluation of the proinhibitors demonstrates that the use of a benzyl ether group appended to the esterase trigger leads to considerably faster kinetics of conversion and enhanced aqueous stability when compared with more conventional approaches where the trigger is directly attached to the inhibitor. Biological assays confirm that all protecting groups effectively cleave in the presence of esterase to generate the active inhibitor. The superior reaction-based prodrug strategies presented here should serve as a platform for esterase-responsive prodrug design in the future.
Collapse
Affiliation(s)
- Christian Perez
- Department of Chemistry and Biochemistry, University of California, San Diego, 9500 Gilman Drive, La Jolla, CA 92093
| | - Kevin B. Daniel
- Department of Chemistry and Biochemistry, University of California, San Diego, 9500 Gilman Drive, La Jolla, CA 92093
| | - Seth M. Cohen
- Department of Chemistry and Biochemistry, University of California, San Diego, 9500 Gilman Drive, La Jolla, CA 92093
| |
Collapse
|
23
|
Rao L, Xue Y, Zheng Y, Lu JR, Ma Y. A novel alkaliphilic bacillus esterase belongs to the 13(th) bacterial lipolytic enzyme family. PLoS One 2013; 8:e60645. [PMID: 23577139 PMCID: PMC3618048 DOI: 10.1371/journal.pone.0060645] [Citation(s) in RCA: 54] [Impact Index Per Article: 4.9] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/15/2012] [Accepted: 03/01/2013] [Indexed: 11/21/2022] Open
Abstract
Background Microbial derived lipolytic hydrolysts are an important class of biocatalysts because of their huge abundance and ability to display bioactivities under extreme conditions. In spite of recent advances, our understanding of these enzymes remains rudimentary. The aim of our research is to advance our understanding by seeking for more unusual lipid hydrolysts and revealing their molecular structure and bioactivities. Methodology/Principal Findings Bacillus. pseudofirmus OF4 is an extreme alkaliphile with tolerance of pH up to 11. In this work we successfully undertook a heterologous expression of a gene estof4 from the alkaliphilic B. pseudofirmus sp OF4. The recombinant protein called EstOF4 was purified into a homologous product by Ni-NTA affinity and gel filtration. The purified EstOF4 was active as dimer with the molecular weight of 64 KDa. It hydrolyzed a wide range of substrates including p-nitrophenyl esters (C2–C12) and triglycerides (C2–C6). Its optimal performance occurred at pH 8.5 and 50°C towards p-nitrophenyl caproate and triacetin. Sequence alignment revealed that EstOF4 shared 71% identity to esterase Est30 from Geobacillus stearothermophilus with a typical lipase pentapeptide motif G91LS93LG95. A structural model developed from homology modeling revealed that EstOF4 possessed a typical esterase 6α/7β hydrolase fold and a cap domain. Site-directed mutagenesis and inhibition studies confirmed the putative catalytic triad Ser93, Asp190 and His220. Conclusion EstOF4 is a new bacterial esterase with a preference to short chain ester substrates. With a high sequence identity towards esterase Est30 and several others, EstOF4 was classified into the same bacterial lipolytic family, Family XIII. All the members in this family originate from the same bacterial genus, bacillus and display optimal activities from neutral pH to alkaline conditions with short and middle chain length substrates. However, with roughly 70% sequence identity, these enzymes showed hugely different thermal stabilities, indicating their diverse thermal adaptations via just changing a few amino acid residues.
Collapse
Affiliation(s)
- Lang Rao
- State Key Laboratory of Microbial Resources, Institute of Microbiology, Chinese Academy of Sciences, Beijing, China
- The Graduate School, Chinese Academy of Sciences, Beijing, China
| | - Yanfen Xue
- State Key Laboratory of Microbial Resources, Institute of Microbiology, Chinese Academy of Sciences, Beijing, China
| | - Yingying Zheng
- State Key Laboratory of Microbial Resources, Institute of Microbiology, Chinese Academy of Sciences, Beijing, China
- The Graduate School, Chinese Academy of Sciences, Beijing, China
| | - Jian R. Lu
- Biological Physics Laboratory, School of Physics and Astronomy, the University of Manchester, Manchester, United Kingdom
- * E-mail: (JRL) (JL); (YM) (YM)
| | - Yanhe Ma
- State Key Laboratory of Microbial Resources, Institute of Microbiology, Chinese Academy of Sciences, Beijing, China
- * E-mail: (JRL) (JL); (YM) (YM)
| |
Collapse
|
24
|
Philippou D, Borzatta V, Capparella E, Moroni L, Field L, Moores G. The interactions between piperonyl butoxide and E4, a resistance-associated esterase from the peach-potato aphid, Myzus persicae Sulzer (Hemiptera: Aphididae). Pest Manag Sci 2013; 69:499-506. [PMID: 22969050 DOI: 10.1002/ps.3400] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/30/2012] [Revised: 07/02/2012] [Accepted: 08/20/2012] [Indexed: 06/01/2023]
Abstract
BACKGROUND It has been reported previously that piperonyl butoxide (PBO) can inhibit both P450 and esterase activity. Although the method by which PBO combines with cytochrome P450 has been identified, the way in which it acts as an esterase inhibitor has not been established. This paper characterises the interactions between PBO and the resistance-associated esterase in Myzus persicae, E4. RESULTS After incubation with PBO/analogues, hydrolysis of 1-naphthyl acetate by E4 is increased, but sequestration of azamethiphos is reduced. Rudimentary in silico modelling suggests PBO docks at the lip of the aromatic gorge. CONCLUSIONS PBO binds with E4 to accelerate small substrates to the active-site triad, while acting as a blockade to larger, insecticidal molecules. Structure-activity studies with analogues of PBO also reveal the essential chemical moieties present in the molecule.
Collapse
|
25
|
Brose SA, Golovko MY. A rapid oxygen exchange on prostaglandins in plasma represents plasma esterase activity that is inhibited by diethylumbelliferyl phosphate with high affinity. Rapid Commun Mass Spectrom 2012; 26:2472-6. [PMID: 22976214 PMCID: PMC3489958 DOI: 10.1002/rcm.6367] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/01/2023]
Abstract
RATIONALE Fatty acids (FA) labeled with (18) O at the carboxyl group, including oxidized species (FA(18) O), are a useful, low-cost, and easy to prepare tool for quantitative and qualitative mass spectrometry (MS) analysis in biological systems. In addition, they are used to trace the fate of FAs in metabolic pathways including FA re-esterification and lipid remodeling pathways. Although a rapid (18) O exchange on FA(18) O in biological systems has been reported, the mechanism contributing to (18) O exchange has not been fully evaluated. This gap in knowledge limits the use of FA(18) O as a standard for MS and complicates data interpretation for FA metabolism in biological systems. METHODS In the present study we have addressed a number of possible mechanisms for a rapid (18) O exchange on prostaglandin E(2) (PGE(2) ) using rat plasma as a model. High-performance liquid chromatography coupled with electrospray ionization triple quadrupole MS in the multiple reaction monitoring mode was used for quantification. RESULTS The major mechanism for a rapid (18) O exchange on PGE(2) (18) O in rat plasma is PGE(2) processing with esterases, while FA re-esterification and non-enzymatic mechanisms do not significantly contribute to this phenomenon. In addition, we report a highly effective inhibition of (18) O exchange with diethylumbelliferyl phosphate that can be used to stabilize FA(18) O in biological samples. CONCLUSIONS These data indicate the necessity to consider esterase activity when FA(18) O are used to study FA metabolism, and the importance of esterase activity inhibition when FA(18) O are used as internal standards for MS analysis in biological systems. In addition, the results provide a rational for the development of new approaches to study esterase activities and affinity towards modified FA.
Collapse
Affiliation(s)
- Stephen A. Brose
- Department of Pharmacology, Physiology, and Therapeutics, University of North Dakota, Grand Forks, ND 58202-9037
| | - Mikhail Y. Golovko
- Department of Pharmacology, Physiology, and Therapeutics, University of North Dakota, Grand Forks, ND 58202-9037
| |
Collapse
|
26
|
Rejón JD, Zienkiewicz A, Rodríguez-García MI, Castro AJ. Profiling and functional classification of esterases in olive (Olea europaea) pollen during germination. Ann Bot 2012; 110:1035-45. [PMID: 22922586 PMCID: PMC3448428 DOI: 10.1093/aob/mcs174] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/06/2023]
Abstract
BACKGROUND AND AIMS A pollen grain contains a number of esterases, many of which are released upon contact with the stigma surface. However, the identity and function of most of these esterases remain unknown. In this work, esterases from olive pollen during its germination were identifided and functionally characterized. METHODS The esterolytic capacity of olive (Olea europaea) pollen was examined using in vitro and in-gel enzymatic assays with different enzyme substrates. The functional analysis of pollen esterases was achieved by inhibition assays by using specific inhibitors. The cellular localization of esterase activities was performed using histochemical methods. KEY RESULTS Olive pollen showed high levels of non-specific esterase activity, which remained steady after hydration and germination. Up to 20 esterolytic bands were identified on polyacrylamide gels. All the inhibitors decreased pollen germinability, but only diisopropyl fluorophosphate (DIFP) hampered pollen tube growth. Non-specific esterase activity is localized on the surface of oil bodies (OBs) and small vesicles, in the pollen intine and in the callose layer of the pollen tube wall. Acetylcholinesterase (AChE) activity was mostly observed in the apertures, exine and pollen coat, and attached to the pollen tube wall surface and to small cytoplasmic vesicles. CONCLUSIONS In this work, for the first time a systematic functional characterization of esterase enzymes in pollen from a plant species with wet stigma has been carried out. Olive pollen esterases belong to four different functional groups: carboxylesterases, acetylesterases, AChEs and lipases. The cellular localization of esterase activity indicates that the intine is a putative storage site for esterolytic enzymes in olive pollen. Based on inhibition assays and cellular localization of enzymatic activities, it can be concluded that these enzymes are likely to be involved in pollen germination, and pollen tube growth and penetration of the stigma.
Collapse
Affiliation(s)
- Juan D. Rejón
- Department of Biochemistry, Cell and Molecular Biology of Plants, Estación Experimental del Zaidín, Consejo Superior de Investigaciones Científicas (CSIC), Profesor Albareda 1, 18008 Granada, Spain
| | - Agnieszka Zienkiewicz
- Department of Biochemistry, Cell and Molecular Biology of Plants, Estación Experimental del Zaidín, Consejo Superior de Investigaciones Científicas (CSIC), Profesor Albareda 1, 18008 Granada, Spain
- Chair of Plant Physiology and Biotechnology, Nicolaus Copernicus University, Gagarina 9, 87-100 Toruń, Poland
| | - María Isabel Rodríguez-García
- Department of Biochemistry, Cell and Molecular Biology of Plants, Estación Experimental del Zaidín, Consejo Superior de Investigaciones Científicas (CSIC), Profesor Albareda 1, 18008 Granada, Spain
| | - Antonio J. Castro
- Department of Biochemistry, Cell and Molecular Biology of Plants, Estación Experimental del Zaidín, Consejo Superior de Investigaciones Científicas (CSIC), Profesor Albareda 1, 18008 Granada, Spain
- For correspondence. E-mail
| |
Collapse
|
27
|
Makhaeva GF, Radchenko EV, Baskin II, Palyulin VA, Richardson RJ, Zefirov NS. Combined QSAR studies of inhibitor properties of O-phosphorylated oximes toward serine esterases involved in neurotoxicity, drug metabolism and Alzheimer's disease. SAR QSAR Environ Res 2012; 23:627-647. [PMID: 22587543 DOI: 10.1080/1062936x.2012.679690] [Citation(s) in RCA: 28] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/31/2023]
Abstract
Oxime reactivation of serine esterases (EOHs) inhibited by organophosphorus (OP) compounds can produce O-phosphorylated oximes (POXs). Such oxime derivatives are of interest, because some of them can have greater anti-EOH potencies than the OP inhibitors from which they were derived. Accordingly, inhibitor properties of 58 POXs against four EOHs, along with pair-wise selectivities between them, have been analysed using different QSAR approaches. EOHs (with their abbreviations and consequences of inhibition in parentheses) comprised acetylcholinesterase (AChE: acute neurotoxicity; cognition enhancement), butyrylcholinesterase (BChE: inhibition of drug metabolism or stoichiometric scavenging of EOH inhibitors; cognition enhancement), carboxylesterase (CaE: inhibition of drug metabolism or stoichiometric scavenging of EOH inhibitors), and neuropathy target esterase (NTE: delayed neurotoxicity). QSAR techniques encompassed linear regression and backpropagation neural networks in conjunction with fragmental descriptors containing labelled atoms, Molecular Field Topology Analysis (MFTA), Comparative Molecular Similarity Index Analysis (CoMSIA), and molecular modelling. All methods provided mostly consistent and complementary information, and they revealed structural features controlling the 'esterase profiles', i.e. patterns of anti-EOH activities and selectivities of the compounds of interest. In addition, MFTA models were used to design a library of compounds having a cognition-enhancement esterase profile suitable for potential application to the treatment of Alzheimer's disease.
Collapse
Affiliation(s)
- G F Makhaeva
- Institute of Physiologically Active Compounds, Chernogolovka, Moscow Region, Russia
| | | | | | | | | | | |
Collapse
|
28
|
Bullangpoti V, Wajnberg E, Audant P, Feyereisen R. Antifeedant activity of Jatropha gossypifolia and Melia azedarach senescent leaf extracts on Spodoptera frugiperda (Lepidoptera: Noctuidae) and their potential use as synergists. Pest Manag Sci 2012; 68:1255-1264. [PMID: 22488906 DOI: 10.1002/ps.3291] [Citation(s) in RCA: 26] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/03/2011] [Revised: 12/12/2011] [Accepted: 01/24/2012] [Indexed: 05/31/2023]
Abstract
BACKGROUND To reduce rates of synthetic insecticide applications, natural product alternatives and synergists are needed. A study has been made of the toxicity of ethanolic senescent leaf extracts (SLEs) of Jatropha gossypifolia and Melia azedarach on larvae of the noctuid pest Spodoptera frugiperda. Their effects as syngergists and inhibitors of several enzyme activities are also reported. RESULTS When added to the diet, M. azedarach SLE showed lower toxicity than J. gossypifolia SLE. However, after 2 weeks on the diet, the M. azedarach SLE proved to be lethal to 100% of the larval population. Artificial diets with both SLEs have an antifeedant effect on armyworm larvae. Acute toxicity after topical application in a dipping assay was relatively low for both J. gossypifolia and M. azedarach SLEs (LC(50) of 2.6 and 1.4 g L(-1), respectively, after 24 h). However, mixtures of the SLEs of M. azedarach and J. gossypifolia had a strong synergistic effect with cypermethrin. Synergism was higher with the J. gossypifolia SLE, perhaps because it contains several natural products with a methylenedioxyphenyl moiety. Both extracts inhibited P450, general esterase and acetylcholinesterase activities in vitro and in vivo. CONCLUSION Both J. gossypifolia and M. azedarach SLEs are antifeedants to armyworm larvae when present in the food, and also have a synergistic effect with cypermethrin in topical assays. Although the synergistic effect is less than with piperonyl butoxide, both SLEs have some inhibitor activity against detoxification enzymes and acetylcholinesterase. Thus J. gossypifolia and M. azedarach SLEs may be considered as ecofriendly approaches for the control of S. frugiperda in order to reduce cypermethrin usage.
Collapse
Affiliation(s)
- Vasakorn Bullangpoti
- Zoology Department, Faculty of Science, Kasetsart University, Bangkok, Thailand.
| | | | | | | |
Collapse
|
29
|
Zheng N, Fung EN, Buzescu A, Arnold ME, Zeng J. Esterase inhibitors as ester-containing drug stabilizers and their hydrolytic products: potential contributors to the matrix effects on bioanalysis by liquid chromatography/tandem mass spectrometry. Rapid Commun Mass Spectrom 2012; 26:1291-1304. [PMID: 22555922 DOI: 10.1002/rcm.6230] [Citation(s) in RCA: 11] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/31/2023]
Abstract
RATIONALE Esterase inhibitors are widely used to stabilize ester-containing drugs in biological matrices for quantitative liquid chromatography/tandem mass spectrometry (LC/MS/MS) assays. These co-existing inhibitors could cause matrix effects on bioanalysis and jeopardize the assay performance. We therefore developed an LC/MS/MS methodology to monitor the fate of inhibitors and evaluate their matrix effects, which is described in this study. METHODS Human plasma containing 20 mM of diisopropylfluorophosphate (DFP), paraoxon, eserine, phenylmethylsulfonyl fluoride (PMSF) or 2-thenoyltrifluoroacetone (TTFA) was extracted by liquid-liquid extraction (LLE) and analyzed by an LC/MS/MS assay for BMS-068645 (a model drug) with additional pre-optimized selected reaction monitoring (SRM) transitions using positive/negative electrospray ionization (ESI) mode for each inhibitor. Hydrolytic products were characterized by product ion or neutral loss scan LC/MS/MS analysis. The matrix effect contribution from each inhibitor was evaluated by post-column infusion of BMS-068645. RESULTS In the extracted samples by LLE, SRM chromatograms revealed the presence of paraoxon, eserine and TTFA with peak intensity of >2.50E08. Three DFP hydrolytic products, diisopropyl phosphate (DP), triisopropyl phosphate (TP) and DP dimer, and one PMSF hydrolytic product, phenymethanesulfonic acid (PMSA), were identified in the extracted samples. In post-column infusion profiles, ion suppression or enhancement was observed in the retention time regions of eserine (~10% suppression), paraoxon (~70% enhancement) and DP dimer (~20% suppression). CONCLUSIONS The SRM transitions described here make it possible to directly monitor the inhibitors and their hydrolytic products. In combination with post-column infusion, this methodology provides a powerful tool to routinely monitor the matrix effects-causing inhibitors, so that their matrix effects on the bioanalysis can be evaluated and minimized.
Collapse
Affiliation(s)
- Naiyu Zheng
- Bioanalytical Sciences, Bristol-Myers Squibb Research & Development, Princeton, NJ 08543, USA
| | | | | | | | | |
Collapse
|
30
|
Joya G, D'Suze G, Salazar V, Rosales A, Sevcik C, Visbal G, Ferreira ATS, Perales J. Scorpion toxins modify phytopathogenic fungus physiology. A possible source of new fungicides. J Agric Food Chem 2011; 59:6327-6337. [PMID: 21510675 DOI: 10.1021/jf200486t] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/30/2023]
Abstract
Seven toxins (F1-F7) were purified from Tityus discrepans scorpion venom on a C18 HPLC column. The compounds were fungitoxic on Macrophomina phaseolina. The molecular masses of F1-F7 were (Da) 1061.1, 7328.8, 7288.3, 7268.5, 7104.6, 6924.6, and 6823.3, respectively. It is not known if F1 is a small peptide or some other kind of organic molecule. Compounds F2-F7 were peptides. The most potent was F7, with a minimal inhibition concentration of 0.4 μg/μL and a concentration for 50% inhibition of 0.13 μg/μL. Fungal esterase activity was abolished by F2, F3, and F5 and inhibited by 89, 60, 58, and 54% by F4, F6, F7, and F1, respectively. F1, F2, F5, and F7 induced an increase on hyphae chitin wall and septum thickness. Peptides F3-F6 induced efflux of the fluorescent dye Na-CoroNa Red complex from hyphae. Only F5 and F6 were inhibited by the prokaryote sodium channel blockers amiloride and mibefradil. Gas chromatography-mass spectrometry analysis suggested that F1, F5, F6, and F7 altered sterol biosynthesis either by inhibiting ergosterol biosynthesis or by producing ergosterol analogues. The peptides affect M. phaseolina viability by three mechanisms: decreasing esterase activity, altering Na(+) membrane permeability, and altering wall sterol biosynthesis. It seems that interfering with sterol synthesis is an important mechanism behind the effect of the fungicideal toxins. However, the antifungal effects at short times are indicative of a direct esterase inhibition, which, with the increased membrane leakiness to Na(+), makes the fungus inviable.
Collapse
Affiliation(s)
- Galax Joya
- Laboratory on Cellular Neuropharmacology, Biophysics and Biochemistry Center, Instituto Venezolano de Investigaciones Científicas (IVIC), Caracas, Venezuela
| | | | | | | | | | | | | | | |
Collapse
|
31
|
Marzo A, Mancinelli A, Cardace G, Monti N, Arrigoni Martelli E. NaF and two other esterase inhibitors unaffect acetyl salicylic acid enzyme hydrolysis. J Pharm Pharmacol 2011; 44:786. [PMID: 1360537 DOI: 10.1111/j.2042-7158.1992.tb05523.x] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [What about the content of this article? (0)] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/27/2022]
|
32
|
Ferrari A, Lascano C, Pechen de D'Angelo AM, Venturino A. Effects of azinphos methyl and carbaryl on Rhinella arenarum larvae esterases and antioxidant enzymes. Comp Biochem Physiol C Toxicol Pharmacol 2011; 153:34-9. [PMID: 20709623 DOI: 10.1016/j.cbpc.2010.08.003] [Citation(s) in RCA: 21] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 03/29/2010] [Revised: 08/03/2010] [Accepted: 08/04/2010] [Indexed: 12/29/2022]
Abstract
Organophosphate (OP) and carbamate pesticides are anticholinesterasic agents also able to alter antioxidant defenses in different organisms. Amphibian larvae are naturally exposed to these pesticides in their aquatic environments located within agricultural areas. We studied the effect of the carbamate carbaryl (CB) and the OP azinphos methyl (AM), compounds extensively used in Northern Patagonian agricultural areas, on reduced glutathione (GSH) levels and the activities of esterases and antioxidant enzymes of the toad Rhinella arenarum larvae. Larvae were exposed 48 h to AM 3 and 6 mg/L or CB 10 and 20 mg/L. Cholinesterase and carboxylesterases were strongly inhibited by CB and AM. In insecticide-exposed larvae, carboxylesterases may serve as alternative targets protecting cholinesterase from inhibition. GSH-S-transferase (GST) activity was significantly increased by CB and AM. Superoxide dismutase activity increased in tadpoles exposed to 6 mg/L AM. Conversely, catalase (CAT) was significantly inhibited by both pesticides. GSH levels, GSH reductase and GSH peroxidase activities were not significantly affected by pesticide exposure. GST increase constitutes an important adaptive response to CB and AM exposure, as this enzyme has been related to pesticide tolerance in amphibian larvae. Besides, the ability to sustain GSH levels in spite of CAT inhibition indicates quite a good antioxidant response. In R. arenarum larvae, CAT and GST activities together with esterases could be used as biomarkers of CB and AM exposure.
Collapse
Affiliation(s)
- Ana Ferrari
- LIBIQUIMA, Facultad de Ingeniería, IDEPA, Universidad Nacional del Comahue-CONICET, Buenos Aires 1400, (8300) Neuquén, Argentina.
| | | | | | | |
Collapse
|
33
|
Rayo J, Muñoz L, Rosell G, Hammock BD, Guerrero A, Luque FJ, Pouplana R. Reactivity versus steric effects in fluorinated ketones as esterase inhibitors: a quantum mechanical and molecular dynamics study. J Mol Model 2010; 16:1753-64. [PMID: 20676708 PMCID: PMC3014912 DOI: 10.1007/s00894-010-0807-4] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/31/2009] [Accepted: 07/09/2010] [Indexed: 11/24/2022]
Abstract
Carboxylesterases (CEs) are a family of ubiquitous enzymes with broad substrate specificity, and their inhibition may have important implications in pharmaceutical and agrochemical fields. One of the most potent inhibitors both for mammalian and insect CEs are trifluoromethyl ketones (TFMKs), but the mechanism of action of these chemicals is not completely understood. This study examines the balance between reactivity versus steric effects in modulating the activity against human carboxylesterase 1. The intrinsic reactivity of the ketone moiety is determined from quantum mechanical computations, which combine gas phase B3LYP calculations with hydration free energies estimated with the IEF/MST model. In addition, docking and molecular dynamics simulations are used to explore the binding mode of the inhibitors along the deep gorge that delineates the binding site. The results point out that the activity largely depends on the nature of the fluorinated ketone, since the activity is modulated by the balance between the intrinsic electrophilicity of the carbonyl carbon atom and the ratio between keto and hydrate forms. However, the results also suggest that the correct alignment of the alkyl chain in the binding site can exert a large influence on the inhibitory activity, as this effect seems to override the intrinsic reactivity features of the fluorinated ketone. Overall, the results sustain a subtle balance between reactivity and steric effects in modulating the inhibitory activity of TFMK inhibitors.
Collapse
Affiliation(s)
- Josep Rayo
- Department of Biological Chemistry and Molecular Modeling, IQAC (CSIC), Jordi Girona 18-26, 08034 Barcelona, Spain
| | - Lourdes Muñoz
- Department of Biological Chemistry and Molecular Modeling, IQAC (CSIC), Jordi Girona 18-26, 08034 Barcelona, Spain
| | - Gloria Rosell
- Pharmaceutical Chemistry, Unity Associated to CSIC, Faculty of Pharmacy, University of Barcelona, Avda. Diagonal 643, 08028 Barcelona, Spain
| | - Bruce D. Hammock
- Department of Entomology and Cancer Center, University of California, Davis, CA 95616, USA
| | - Angel Guerrero
- Department of Biological Chemistry and Molecular Modeling, IQAC (CSIC), Jordi Girona 18-26, 08034 Barcelona, Spain
| | - F. Javier Luque
- Department of Physical Chemistry and Institute of Biomedicine (IBUB), Faculty of Pharmacy, University of Barcelona, Avda. Diagonal 643, 08028 Barcelona, Spain
| | - Ramon Pouplana
- Department of Physical Chemistry and Institute of Biomedicine (IBUB), Faculty of Pharmacy, University of Barcelona, Avda. Diagonal 643, 08028 Barcelona, Spain
| |
Collapse
|
34
|
Leite PZ, Margarido TCS, de Lima D, Rossa-Feres DDC, de Almeida EA. Esterase inhibition in tadpoles of Scinax fuscovarius (Anura, Hylidae) as a biomarker for exposure to organophosphate pesticides. Environ Sci Pollut Res Int 2010; 17:1411-1421. [PMID: 20383595 DOI: 10.1007/s11356-010-0326-y] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/30/2009] [Accepted: 03/16/2010] [Indexed: 05/29/2023]
Abstract
PURPOSE Organophosphate pesticides (OPs) are among the most used insecticides in agriculture, causing the inhibition of esterases like acetylcholinesterase (AChE), butyrylcholinesterase (BChE) and carboxylesterase (CbE). Pesticides can reach the aquatic environment, posing risks to non-target organisms, including tadpoles. METHODS In this work, we characterized the activities of AChE, BChE and CbE in tadpoles of the snouted treefrog Scinax fuscovarius, and verified their in vitro sensibility to different inhibitors [phenylmethane sulfonyl fluoride (PMSF), tetra-isopropylpyrophosphamide (iso-OMPA) and the OP diazinon]. In vivo effects of diazinon and esterase recovery after 2-pyridine-aldoxime (2-PAM) treatment of the protein extract were also studied in tadpoles with distinct stages of development exposed to 1 and 3 mg/l for 2 and 7 days. RESULTS Optimal conditions were established for AChE and CbE; BChE activity was negligible. PMSF affected esterase activities and is not recommended for homogenization buffers. Iso-OMPA treatment caused no changes in AChE and CbE activities, but diazinon inhibited these enzymes in a dose-responsive manner. In vivo, CbE activity was insensitive to diazinon in younger tadpoles, but inhibited after 2 days of exposure in more developed tadpoles. AChE activity was inhibited after 2 and 7 days of exposure, in a dose-responsive manner. Esterase reactivation by 2-PAM was obtained both in vitro and in vivo. CONCLUSIONS (1) Tadpoles can be adequate sentinel organisms in biomonitoring studies of OP contamination; (2) AChE was more sensitive than CbE to diazinon; (3) tadpoles from earlier developmental stages seems to be less responsive to OPs; (4) AChE activity was sensitive to diazinon in both development stages, being a better OP biomarker.
Collapse
Affiliation(s)
- Patricia Zazeri Leite
- Departamento de Química e Ciências Ambientais, Instituto de Biociências, Letras e Ciências Exatas, Universidade Estadual Paulista, Rua Cristóvão Colombo 2265, CEP 15054-000, São José do Rio Preto, Brazil
| | | | | | | | | |
Collapse
|
35
|
Collange B, Wheelock CE, Rault M, Mazzia C, Capowiez Y, Sanchez-Hernandez JC. Inhibition, recovery and oxime-induced reactivation of muscle esterases following chlorpyrifos exposure in the earthworm Lumbricus terrestris. Environ Pollut 2010; 158:2266-2272. [PMID: 20334963 DOI: 10.1016/j.envpol.2010.02.009] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/15/2009] [Revised: 11/17/2009] [Accepted: 02/11/2010] [Indexed: 05/29/2023]
Abstract
Assessment of wildlife exposure to organophosphorus (OP) pesticides generally involves the measurement of cholinesterase (ChE) inhibition, and complementary biomarkers (or related endpoints) are rarely included. Herein, we investigated the time course inhibition and recovery of ChE and carboxylesterase (CE) activities in the earthworm Lumbricus terrestris exposed to chlorpyrifos, and the ability of oximes to reactivate the phosphorylated ChE activity. Results indicated that these esterase activities are a suitable multibiomarker scheme for monitoring OP exposure due to their high sensitivity to OP inhibition and slow recovery to full activity levels following pesticide exposure. Moreover, oximes reactivated the inhibited ChE activity of the earthworms exposed to 12 and 48 mg kg(-1) chlorpyrifos during the first week following pesticide exposure. This methodology is useful for providing evidence for OP-mediated ChE inhibition in individuals with a short history of OP exposure (< or = 1 week); resulting a valuable approach for assessing multiple OP exposure episodes in the field.
Collapse
Affiliation(s)
- B Collange
- Universite d'Avignon et des Pays de Vaucluse, UMR 406 Abeilles et Environnement, Site AGROPARC, F-84914, Avignon Cede 09, France
| | | | | | | | | | | |
Collapse
|
36
|
Tartarotti E, Neto FL, Ceron CR. Esterase patterns in species of the triatome bug Rhodnius. Med Vet Entomol 2010; 24:26-31. [PMID: 20377728 DOI: 10.1111/j.1365-2915.2009.00827.x] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/29/2023]
Abstract
The aim of the present study was to analyse esterase patterns in three triatomine species of Rhodnius genus. Four loci, Est 1, Est 2, Est 3 and Est 4, were found. The corresponding enzymes were characterized as carboxylesterases (E.C. 3.1.1.1) or cholinesterases (E.C. 3.1.1.8) based on inhibitory experiments, using eserine sulphate, malathion, mercury chloride, p-chloromercuribenzoate (pCMB) and iodoacetamide. Low genetic variability was observed: Est 1, Est 2 and Est 3 were monomorphic in Rhodnius domesticus, Rhodnius robustus and Rhodnius neivai, whereas locus Est 4 was polymorphic in the first two species. The UPGMA analysis based on esterase genotypic frequencies indicated greater similarity between R. domesticus and R. robustus when compared with R. neivai. The present study expands our knowledge about genetic variability among triatomines and accords with the hypothesis that R. domesticus is a species derived from R. robustus.
Collapse
Affiliation(s)
- E Tartarotti
- Departamento de Biologia, Instituto de Biociências, Letras e Ciências Exatas, Universidade Estadual Paulista, UNESP, São Paulo, Brazil.
| | | | | |
Collapse
|
37
|
Achaleke J, Martin T, Ghogomu RT, Vaissayre M, Brévault T. Esterase-mediated resistance to pyrethroids in field populations of Helicoverpa armigera (Lepidoptera: Noctuidae) from Central Africa. Pest Manag Sci 2009; 65:1147-1154. [PMID: 19548293 DOI: 10.1002/ps.1807] [Citation(s) in RCA: 17] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/28/2023]
Abstract
BACKGROUND Evolution of pyrethroid resistance in the cotton bollworm Helicoverpa armigera (Hübner) (Lepidoptera: Noctuidae) threatens continued cotton production in Central Africa. Dose-response bioassays were conducted on area-wide collection of bollworm populations from major host plants, while biochemical techniques were used to evaluate basic mechanisms underlying resistance. RESULTS Pyrethroid resistance is primarily associated with detoxification by enhanced esterase activity. High resistance to cypermethrin (RF = 67-1771), cross-resistance to deltamethrin (RF = 60-2972) and lack of cross-resistance to the non-ester pyrethroid etofenprox (RF = 2-10) were observed among H. armigera field populations and laboratory-selected strains. Enzymatic assays showed that esterase activity, but not oxidase content or glutathione-S-transferase activity, was positively correlated with resistance to cypermethrin. Pretreatment with piperonyl butoxide (PBO) resulted in significant synergism with cypermethrin in 6/10 field populations, but not in the laboratory-selected strain, indicating that additional mechanisms such as mixed-function oxidase (MFO) may be involved in field resistance. The absence of cross-resistance to DDT ruled out a possible target-site modification. CONCLUSION Knowledge of the mechanisms involved in pyrethroid resistance and the lack of cross-resistance to spinosad and indoxacarb is a key to devising new resistance management strategies aimed at restoring the efficacy of pyrethroid-based programmes.
Collapse
|
38
|
|
39
|
|
40
|
Krajnović-Ozretić M, Zikić R. Esterase polymorphism in the Adriatic sardine (Sardina pilchardus Walb.). 1. Electrophoretic and biochemical properties of the serum and tissue esterases. Anim Blood Groups Biochem Genet 2009; 6:201-13. [PMID: 1211667 DOI: 10.1111/j.1365-2052.1975.tb01365.x] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/26/2022]
Abstract
At least four zones of esterase activity designated I, II, III and IV were found after electrophoretic separation of sera and soluble extracts of sardine tissues on starch gel. Each zone consisted of one or more bands that were distinguishable from other zones by electrophoretic mobility, substrate specificity and sensitivity to various inhibitors. Polymorphism was noted in zones I, II and III, while zone IV consisted of a single band. A genetic interpretation of the polymorphism was given for zone I esterases in the tissue, which appears to be controlled by four codominant alleles. The zones designated I, II and IV in the sera and II, III and IV in the liver were characterized as carboxylesterases, zone II in the sera was the only one with cholinesterase activity, while zone I in the liver tissue was unclassifiable.
Collapse
|
41
|
Laake K, Gjonnaess H, Fagerhol MK. Components of the kallikrein-kinin system and the spontaneous cold activation of factor VII in human plasma. Acta Pharmacol Toxicol (Copenh) 2009; 33:229-40. [PMID: 4800785 DOI: 10.1111/j.1600-0773.1973.tb02010.x] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/12/2023]
|
42
|
Abstract
Studies were made (at 37 degrees, pH 7.6) on the interaction of some organophosphorus compounds and carboxylic acid esters with cholinesterases (EC 3.1.1.7 and EC 3.1.1.8) and A-esterases (EC 3.1.1.2) in homogenates of Schistosoma mansoni (adults and cercariae) and Schistosoma haematobium (adults). The results are compared with those obtained from the same reactions in other parasitic helminths and in mammalian tissues. Metrifonate (0,0-dimethyl-2,2,2-trichloro-1-hydroxyethyl phosphonate) does not seem to react with cholinesterases from parasites or mammals. Dichlorvos (0,0-dimethyl-2,2-dichlorovinyl phosphate) is a phosphorylating inhibitor; the rate constants of inhibition of cholinesterases from schistosomes are in the order of 10(5) M-1 min.-1. Similar or lower rate constants (10(4) M-1 min.-1) are found for cholinesterase inhibition in other parasitic helminths and mammals. S. mansoni and S. haematobium hydrolyse carboxylic acid esters (10 mM) in decreasing order: phenylacetate (about 2 mumol per hour per mg protein), acetylthiocholine, propionylthiocholine, butyrylthiocholine. Dichlorvos (10 mM) is hydrolysed by S. mansoni and S. haematobium at about the same rate as by mammalian erythrocytes and human sera (about 10 mumol per hour per gram wet weight). Neither paraoxon (0,0-diethyl-4-nitrophenyl phosphate) nor methyl-paraoxon are hydrolysed by S. mansoni and S. haematobium, although both compounds are good substrates for mammalian A-esterases. The stability of metrifonate and dichlorvos in buffer solutions was also determined (at 37 degrees). Metrifonate is about equally stable in bicarbonate buffer (pH 7.6) and phosphate buffer (pH 7.4) (t 1/2 = 1.5 and 2.6 hrs, respectively), while dichlorvos is considerably more stable in bicarbonate (t 1/2 = (36 hrs) than in phosphate buffer (t 1/2 = 2.9 hrs).
Collapse
|
43
|
Moores GD, Philippou D, Borzatta V, Trincia P, Jewess P, Gunning R, Bingham G. An analogue of piperonyl butoxide facilitates the characterisation of metabolic resistance. Pest Manag Sci 2009; 65:150-154. [PMID: 18951417 DOI: 10.1002/ps.1661] [Citation(s) in RCA: 20] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/27/2023]
Abstract
BACKGROUND Previous work has demonstrated that piperonyl butoxide (PBO) not only inhibits microsomal oxidases but also resistance-associated esterases. The ability to inhibit both major metabolic resistance enzymes makes it an ideal synergist to enhance xenobiotics but negates the ability to differentiate which enzyme group is responsible for conferring resistance. RESULTS This study examines an analogue that retains the ability to inhibit esterases but is restricted in its ability to act on microsomal oxidases, thus allowing an informed decision on resistance enzymes to be made when used in conjunction with the parent molecule. CONCLUSION Using examples of resistant insects with well-characterised resistance mechanisms, a combination of PBO and analogue allows identification of the metabolic mechanism responsible for conferring resistance. The relative potency of PBO as both an esterase inhibitor and an oxidase inhibitor is also discussed.
Collapse
|
44
|
Abstract
BACKGROUND Conventional in vitro assays sometimes fail to reveal esterase inhibition by piperonyl butoxide (PBO), although synergism studies suggest loss of esterase-mediated sequestration of insecticide does take place. A new in vitro assay has been devised that routinely reveals binding between PBO and these esterases. RESULTS The new 'esterase interference' assay detects the blockade of resistance-associated esterases in a species, Myzus persicae Sülzer, where this has not previously been seen. The assay also demonstrates directly the protective effect esterases may confer to target sites of insecticides. CONCLUSION The new assay reveals esterase blockade by PBO and thus has the potential to be used as a high-throughput screening method for other potential synergists.
Collapse
Affiliation(s)
- Anna C Khot
- Rothamsted Research, Harpenden, Hertfordshire AL5 2JQ, UK
| | | | | | | |
Collapse
|
45
|
Lee S, Gustafson G, Skamnioti P, Baloch R, Gurr S. Host perception and signal transduction studies in wild-type Blumeria graminis f. sp. hordei and a quinoxyfen-resistant mutant implicate quinoxyfen in the inhibition of serine esterase activity. Pest Manag Sci 2008; 64:544-555. [PMID: 18229890 DOI: 10.1002/ps.1538] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/25/2023]
Abstract
BACKGROUND Quinoxyfen is a potent and effective fungicide, hitherto considered to control powdery mildew disease by perturbing signal transduction during early germling differentiation. The aim of this paper is to understand the mode of action of quinoxyfen by comparing the perception of host-derived signals and signal relay in a wild-type Blumeria graminis f. sp. hordei EM Marchal (Bgh) (WT/IM82) and a quinoxyfen-resistant field isolate (QR/2B11). RESULTS QR/2B11 germinates more promiscuously on host-like and artificial surfaces than the quinoxyfen-sensitive WT/IM82. The pivotal role of host cuticle deprivation in the formation of hooked appressorial germ tubes (hAGTs) in WT/IM82 and a dramatic drop in germling differentiation in the presence of the mildewicide are demonstrated. QR/2B11 strain shows a dependence on host cuticle-like features for hAGT formation but no significant difference between germling differentiation in the presence or absence of quinoxyfen. PKC-inhibitor Ro 318220 induces morphological changes similar to those seen in quinoxyfen-treated germlings. PKC1 transcript accumulation is equivalently upregulated by quinoxyfen in QR/2B11 and WT/IM82 strains, but Bgh cutinase CUT1 transcript is 8 times more abundant in QR/2B11 conidia than in WT/IM82 conidia. Quinoxyfen inhibits serine esterase activity in WT/IM82, but not in QR/2B11. CONCLUSION Collectively, these data suggest that quinoxyfen interferes with the perception of host-derived signals required for full germling differentiation, and that QR/2B11 bypasses the need for such signals. Moreover, quinoxyfen appears to target serine esterase activity, with a downstream perturbation in signal transduction; this represents the first demonstrable biochemical difference between the quinoxyfen-resistant and -sensitive isolates.
Collapse
Affiliation(s)
- Susannah Lee
- Department of Plant Sciences, University of Oxford, South Parks Road, Oxford OX1 3RB, UK
| | | | | | | | | |
Collapse
|
46
|
Walz I, Schwack W. Multienzyme inhibition assay for residue analysis of insecticidal organophosphates and carbamates. J Agric Food Chem 2007; 55:10563-10571. [PMID: 18052096 DOI: 10.1021/jf072348k] [Citation(s) in RCA: 13] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/25/2023]
Abstract
A recently developed spectrophotometric assay for the detection of organophosphorus and carbamate insecticides by means of cutinase inhibition has been successfully extended to two esterases derived from Bacillus subtilis (BS2) and rabbit liver. These esterases were selected because of their high sensitivity to the examined insecticide classes and their pronounced inhibition profile. With inhibition constants (ki) of 2.0x10(7) and 2.6x10(6) L/(mol.min) for rabbit liver esterase and BS2, respectively, chlorpyrifos oxon proved to be the strongest inhibitor directly followed by paraoxon. As compared to choline esterases and the recently studied cutinase, both esterases are surprisingly strongly inhibited by organophosphorus thions, showing k i in the range of 5.3x10(2) to 2.3x10(4) L/(mol.min). All tested insecticidal carbamates were also inhibitors of BS2 and rabbit liver esterase, albeit in a rather uniform manner. Generally, both enzymes were found to be about 2 orders of magnitude more sensitive on the studied insecticides than cutinase even with an enhanced sensitivity against plant matrix effects. Plant extracts, obtained according to the QuEChERS method, were subjected to solid-phase extraction (SPE) using a mixed mode strong anion exchanger/primary secondary amine sorbent and C18endcapped cartridges for superior cleanup. With spiked samples of apple juice, best recoveries of 73% (+/-61%), 94% (+/-25%), and 134% (+/-17%) were obtained for chlorpyrifos, parathion-methyl, and paraoxon, respectively. Results of exemplarily performed liquid chromatography-mass spectrometry control measurements were well in accordance with measurements obtained by enzyme inhibition.
Collapse
Affiliation(s)
- Ingrid Walz
- Institut für Lebensmittelchemie, Universität Hohenheim, Stuttgart, Germany
| | | |
Collapse
|
47
|
Pan H, Kopecková P, Liu J, Wang D, Miller SC, Kopecek J. Stability in plasmas of various species of HPMA copolymer-PGE1 conjugates. Pharm Res 2007; 24:2270-80. [PMID: 17899324 DOI: 10.1007/s11095-007-9449-3] [Citation(s) in RCA: 17] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/18/2007] [Accepted: 08/28/2007] [Indexed: 10/22/2022]
Abstract
PURPOSE To determine the stability of HPMA copolymer-prostaglandin E(1) (PGE(1)) conjugates in plasmas of different species and to identify the enzymes responsible for the cleavage of the ester bond. METHODS The conjugates were incubated in human, rat, and mouse plasma at 37 degrees C in the presence and absence of specific esterase inhibitors. The released PGE(1) was analyzed using an HPLC assay. To evaluate the effect of the conformation of the conjugate on the rate of PGE(1) release, its structure was modified by the attachment of hydrophobic side chains. RESULTS The rate of PGE(1) release was strongly species dependent. Whereas the conjugate was stable in human plasma, the PGE(1) release in rat or mouse plasma was substantial. In rat plasma, the ester bond cleavage was mainly catalyzed by butyrylcholinesterase; in mouse plasma, in addition to butyrylcholinesterase, carboxylesterase also contributed to the cleavage. The formation of compact polymer coils stabilized the ester bond. CONCLUSIONS HPMA copolymer-PGE(1) conjugates are strong candidates as novel therapeutics for the treatment of osteoporosis. The observed species differences in plasma stability of ester bonds are of importance, because the ovariectomized rat model is recommended by the FDA for pre-clinical evaluation.
Collapse
Affiliation(s)
- Huaizhong Pan
- Department of Pharmaceutics and Pharmaceutical Chemistry/CCCD, University of Utah, Salt Lake City, Utah 84112, USA
| | | | | | | | | | | |
Collapse
|
48
|
Rodríguez MM, Bisset JA, Fernández D. [Determination in vivo of the role of esterase and glutathione transferase enzymes in pyrethroid resistance of Aedes aegypti (Diptera: Culicidae)]. Rev Cubana Med Trop 2007; 59:209-212. [PMID: 23427458] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 06/01/2023]
Abstract
An in vivo study of two synergists, that is, Triphenil phosphate -specific esterase inhibitor- and ethacrynic acid -specific gluthation transferase inhibitor- was performed to determine if these enzymes were responsible for pyrethroid resistance of Aedes aegypti. To this end, two insecticide resistant Aedes aegypti strains were used, one strain selected with temephos by six selection generations (SAN-F6) and the other strain with delmamethrin by 12 selection generations (SAN-F12), being both strains resistant to pyrethroid insecticices. Through the use of TPP and EA synergists, it was proved that esterase and gluthation-s-transferase (GST) enzymes were responsible for pryrethroid resistance of these strains. These results showed the existence of cross-resistance and multidrug resistance, which should be taken into account for insecticide use strategies aimed at vector control.
Collapse
|
49
|
Ekinci D, Beydemir S, Alim Z. Some drugs inhibit in vitro hydratase and esterase activities of human carbonic anhydrase-I and II. Pharmacol Rep 2007; 59:580-587. [PMID: 18048959] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/02/2007] [Revised: 09/24/2007] [Indexed: 05/25/2023]
Abstract
In this study, we determined the in vitro inhibitory effects of ceftriaxone sodium, imipenem and ornidazole on hydratase and esterase activities of human erythrocyte carbonic anhydrase-I and II isozymes (CA I and II). Human erythrocyte CAI and II isozymes were purified by Sepharose-4B L-tyrosine affinity chromatography column with a yield of 30% and 40%, a specific activity of 920 and 8,000 EU/mg protein, respectively. In the overall purification procedure, human carbonic anhydrase (hCA)-I and (hCA)-II were purified 104 and 900-fold, respectively. In order to determine the purity of the enzymes, SDS-PAGE was performed. Inhibitory effects of the drugs on hCA-I and hCA-II were determined by using colorimetric method for CO2-hydratase activity assay and spectrophotometric method for esterase activity assay. P-Nitrophenyl acetate was used as a substrate in the spectrophotometric esterase activity assay. The obtained IC50 values (inhibitor concentrations which cause 50% inhibition of in vitro enzyme activity) for esterase activity were 1.900, 0.008, 0.318 mM for hCA-I and 2.542, 0.0258, 0.343 mM for hCA-II for ceftriaxone sodium, imipenem and ornidazole, respectively. IC50 values for CO2-hydratase activity were 0.864, 0.00354, 0.131 mM for hCA-I and 1.118, 0.0214, 0.263 mM for hCA-II for ceftriaxone sodium, imipenem and ornidazole, respectively. In conclusion, ceftriaxone sodium, imipenem and ornidazole showed inhibitory effects on human erythrocte carbonic anhydrase-I and II isozyme activities under in vitro conditions.
Collapse
Affiliation(s)
- Deniz Ekinci
- Atatürk University, Faculty of Science and Arts, Department of Chemistry, 25240 Erzurum, Turkey
| | | | | |
Collapse
|
50
|
Chen J, Yang L, Foulks JM, Weyrich AS, Marathe GK, McIntyre TM. Intracellular PAF catabolism by PAF acetylhydrolase counteracts continual PAF synthesis. J Lipid Res 2007; 48:2365-76. [PMID: 17693621 DOI: 10.1194/jlr.m700325-jlr200] [Citation(s) in RCA: 37] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022] Open
Abstract
Stimulated inflammatory cells synthesize platelet-activating factor (PAF), but lysates of these cells show little enhancement in PAF synthase activity. We show that human neutrophils contain intracellular plasma PAF acetylhydrolase (PLA2G7), an enzyme normally secreted by monocytes. The esterase inhibitors methyl arachidonoylfluorophosphonate (MAFP), its linoleoyl homolog, and Pefabloc inhibit plasma PAF acetylhydrolase. All of these inhibitors induced PAF accumulation by quiescent neutrophils and monocytes that was equivalent to agonist stimulation. Agonist stimulation after esterase inhibition did not further increase PAF accumulation. PAF acetylhydrolase activity in intact neutrophils was reduced, but not abolished, by agonist stimulation. Erythrocytes, which do not participate in the acute inflammatory response, inexplicably express the type I PAF acetylhydrolase, whose only known substrate is PAF. Inhibition of this enzyme by MAFP caused PAF accumulation by erythrocytes, which was hemolytic in the absence of PAF acetylhydrolase activity. We propose that PAF is continuously synthesized by a nonselective acyltransferase activity(ies) found even in noninflammatory cells as a component of membrane remodeling, which is then selectively and continually degraded by intracellular PAF acetylhydrolase activity to modulate PAF production.
Collapse
Affiliation(s)
- Jiawei Chen
- Department of Cell Biology, Cleveland Clinic Lerner College of Medicine, Cleveland Clinic, Cleveland, OH 44195, USA
| | | | | | | | | | | |
Collapse
|