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Conceição RAD, von Ranke N, Azevedo L, Franco D, Nadur NF, Kummerle AE, Barbosa MLDC, Souza AMT. Structure-based design of new N-benzyl-piperidine derivatives as multitarget-directed AChE/BuChE inhibitors for Alzheimer's disease. J Cell Biochem 2023; 124:1734-1748. [PMID: 37796142 DOI: 10.1002/jcb.30483] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/03/2023] [Revised: 09/16/2023] [Accepted: 09/20/2023] [Indexed: 10/06/2023]
Abstract
The pathogenic complexity of Alzheimer's disease (AD) demands the development of multitarget-directed agents aiming at improving actual pharmacotherapy. Based on the cholinergic hypothesis and considering the well-established role of butyrylcholinesterase (BuChE) in advanced stages of AD, the chemical structure of the acetylcholinesterase (AChE) inhibitor drug donepezil (1) was rationally modified for the design of new N-benzyl-piperidine derivatives (4a-d) as potential multitarget-direct AChE and BuChE inhibitors. The designed analogues were further studied through the integration of in silico and in vitro methods. ADMET predictions showed that 4a-d are anticipated to be orally bioavailable, able to cross the blood-brain barrier and be retained in the brain, and to have low toxicity. Computational docking and molecular dynamics indicated the formation of favorable complexes between 4a-d and both cholinesterases. Derivative 4a presented the lowest binding free energy estimation due to interaction with key residues from both target enzymes (-36.69 ± 4.47 and -32.23 ± 3.99 kcal/mol with AChE and BuChE, respectively). The in vitro enzymatic assay demonstrated that 4a was the most potent inhibitor of AChE (IC50 2.08 ± 0.16 µM) and BuChE (IC50 7.41 ± 0.44 µM), corroborating the in silico results and highlighting 4a as a novel multitarget-directed AChE/BuChE inhibitor.
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Affiliation(s)
- Raissa Alves da Conceição
- Laboratory of Molecular Modeling & QSAR (ModMolQSAR), Faculty of Pharmacy, Federal University of Rio de Janeiro, Rio de Janeiro, Brazil
- Laboratory of Organic Synthesis and Medicinal Chemistry (LaSOQuiM), Faculty of Pharmacy, Federal University of Rio de Janeiro, Rio de Janeiro, Brazil
| | - Natalia von Ranke
- Laboratory of Molecular Modeling & QSAR (ModMolQSAR), Faculty of Pharmacy, Federal University of Rio de Janeiro, Rio de Janeiro, Brazil
| | - Luciana Azevedo
- Laboratory of Molecular Diversity and Medicinal Chemistry (LaDMol-QM), Institute of Chemistry, Federal Rural University of Rio de Janeiro, Seropédica, Brazil
| | - Daiana Franco
- Laboratory of Molecular Diversity and Medicinal Chemistry (LaDMol-QM), Institute of Chemistry, Federal Rural University of Rio de Janeiro, Seropédica, Brazil
| | - Nathalia Fonseca Nadur
- Laboratory of Molecular Diversity and Medicinal Chemistry (LaDMol-QM), Institute of Chemistry, Federal Rural University of Rio de Janeiro, Seropédica, Brazil
| | - Arthur Eugen Kummerle
- Laboratory of Molecular Diversity and Medicinal Chemistry (LaDMol-QM), Institute of Chemistry, Federal Rural University of Rio de Janeiro, Seropédica, Brazil
| | - Maria Letícia de C Barbosa
- Laboratory of Organic Synthesis and Medicinal Chemistry (LaSOQuiM), Faculty of Pharmacy, Federal University of Rio de Janeiro, Rio de Janeiro, Brazil
| | - Alessandra M T Souza
- Laboratory of Molecular Modeling & QSAR (ModMolQSAR), Faculty of Pharmacy, Federal University of Rio de Janeiro, Rio de Janeiro, Brazil
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2
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Bao LQ, Baecker D, Mai Dung DT, Phuong Nhung N, Thi Thuan N, Nguyen PL, Phuong Dung PT, Huong TTL, Rasulev B, Casanola-Martin GM, Nam NH, Pham-The H. Development of Activity Rules and Chemical Fragment Design for In Silico Discovery of AChE and BACE1 Dual Inhibitors against Alzheimer's Disease. Molecules 2023; 28:molecules28083588. [PMID: 37110831 PMCID: PMC10142303 DOI: 10.3390/molecules28083588] [Citation(s) in RCA: 3] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/17/2023] [Revised: 04/15/2023] [Accepted: 04/18/2023] [Indexed: 04/29/2023] Open
Abstract
Multi-target drug development has become an attractive strategy in the discovery of drugs to treat of Alzheimer's disease (AzD). In this study, for the first time, a rule-based machine learning (ML) approach with classification trees (CT) was applied for the rational design of novel dual-target acetylcholinesterase (AChE) and β-site amyloid-protein precursor cleaving enzyme 1 (BACE1) inhibitors. Updated data from 3524 compounds with AChE and BACE1 measurements were curated from the ChEMBL database. The best global accuracies of training/external validation for AChE and BACE1 were 0.85/0.80 and 0.83/0.81, respectively. The rules were then applied to screen dual inhibitors from the original databases. Based on the best rules obtained from each classification tree, a set of potential AChE and BACE1 inhibitors were identified, and active fragments were extracted using Murcko-type decomposition analysis. More than 250 novel inhibitors were designed in silico based on active fragments and predicted AChE and BACE1 inhibitory activity using consensus QSAR models and docking validations. The rule-based and ML approach applied in this study may be useful for the in silico design and screening of new AChE and BACE1 dual inhibitors against AzD.
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Affiliation(s)
- Le-Quang Bao
- Department of Pharmaceutical Chemistry, Hanoi University of Pharmacy, 13-15 Le Thanh Tong, Hoan Kiem, Hanoi 10000, Vietnam
| | - Daniel Baecker
- Department of Pharmaceutical and Medicinal Chemistry, Institute of Pharmacy, University of Greifswald, Friedrich-Ludwig-Jahn-Straße 17, 17489 Greifswald, Germany
| | - Do Thi Mai Dung
- Department of Pharmaceutical Chemistry, Hanoi University of Pharmacy, 13-15 Le Thanh Tong, Hoan Kiem, Hanoi 10000, Vietnam
| | - Nguyen Phuong Nhung
- Department of Pharmaceutical Chemistry, Hanoi University of Pharmacy, 13-15 Le Thanh Tong, Hoan Kiem, Hanoi 10000, Vietnam
| | - Nguyen Thi Thuan
- Department of Pharmaceutical Chemistry, Hanoi University of Pharmacy, 13-15 Le Thanh Tong, Hoan Kiem, Hanoi 10000, Vietnam
| | - Phuong Linh Nguyen
- College of Computing & Informatics, Drexel University, 3141 Chestnut St., Philadelphia, PA 19104, USA
| | - Phan Thi Phuong Dung
- Department of Pharmaceutical Chemistry, Hanoi University of Pharmacy, 13-15 Le Thanh Tong, Hoan Kiem, Hanoi 10000, Vietnam
| | - Tran Thi Lan Huong
- Department of Pharmaceutical Chemistry, Hanoi University of Pharmacy, 13-15 Le Thanh Tong, Hoan Kiem, Hanoi 10000, Vietnam
| | - Bakhtiyor Rasulev
- Department of Coatings and Polymeric Materials, North Dakota State University, Fargo, ND 58102, USA
| | | | - Nguyen-Hai Nam
- Department of Pharmaceutical Chemistry, Hanoi University of Pharmacy, 13-15 Le Thanh Tong, Hoan Kiem, Hanoi 10000, Vietnam
| | - Hai Pham-The
- Department of Pharmaceutical Chemistry, Hanoi University of Pharmacy, 13-15 Le Thanh Tong, Hoan Kiem, Hanoi 10000, Vietnam
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Zhang M, Yan X, Wang L, Liu Z. Facile Synthesis of New Imidazo[4',5':4,5]benzo[1,2-d] isoxazol-6-one Derivatives and In Silico Studies of Their Drug-like Profiles. ORG PREP PROCED INT 2021. [DOI: 10.1080/00304948.2021.1920303] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/20/2022]
Affiliation(s)
- Maofeng Zhang
- College of Pharmacy, Jiangsu Solid Preparation Engineering Technology Research and Development Center, Taizhou Polytechnic College, Taizhou, P. R. China
| | - Xingli Yan
- College of Pharmacy, Jiangsu Solid Preparation Engineering Technology Research and Development Center, Taizhou Polytechnic College, Taizhou, P. R. China
| | - Lizhong Wang
- College of Pharmacy, Jiangsu Solid Preparation Engineering Technology Research and Development Center, Taizhou Polytechnic College, Taizhou, P. R. China
| | - Zhuyun Liu
- College of Pharmacy, Jiangsu Solid Preparation Engineering Technology Research and Development Center, Taizhou Polytechnic College, Taizhou, P. R. China
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4
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Pourshojaei Y, Eskandari K, Asadipour A. Highly Significant Scaffolds to Design and Synthesis Cholinesterase Inhibitors as Anti-Alzheimer Agents. Mini Rev Med Chem 2019; 19:1577-1598. [DOI: 10.2174/1389557519666190719143112] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/23/2018] [Revised: 06/02/2019] [Accepted: 06/25/2019] [Indexed: 12/19/2022]
Abstract
:
Alzheimer, a progressive disease, is a common term for memory loss which interferes with
daily life through severe influence on cognitive abilities. Based on the cholinergic hypothesis, and Xray
crystallographic determination of the structure of acetylcholinesterase (AChE) enzyme, the level of
acetylcholine (ACh, an important neurotransmitter associated with memory) in the hippocampus and
cortex area of the brain has a direct effect on Alzheimer. This fact encourages scientists to design and
synthesize a wide range of acetylcholinesterase inhibitors (AChEIs) to control the level of ACh in the
brain, keeping in view the crystallographic structure of AChE enzyme and drugs approved by the Food
and Drug Administration (FDA).
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AChEIs have slightly diverse pharmacological properties, but all of them work by inhibiting the segregation
of ACh by blocking AChE. We reviewed significant scaffolds introduced as AChEIs. In some
studies, the activity against butyrylcholinesterase (BuChE) has been evaluated as well because BuChE
is a similar enzyme to neuronal acetylcholinesterase and is capable of hydrolyzing ACh. In order to
study AChEIs effectively, we divided them structurally into 12 classes and briefly explained effective
AChEIs and compared their activities against AChE enzyme.
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Affiliation(s)
- Yaghoub Pourshojaei
- Department of Medicinal Chemistry, Faculty of Pharmacy & Pharmaceutics Research Center, Institute of Neuropharmacology, Kerman University of Medical Sciences, Kerman, Iran
| | - Khalil Eskandari
- Department of Medicinal Chemistry, Faculty of Pharmacy & Pharmaceutics Research Center, Institute of Neuropharmacology, Kerman University of Medical Sciences, Kerman, Iran
| | - Ali Asadipour
- Department of Medicinal Chemistry, Faculty of Pharmacy & Pharmaceutics Research Center, Institute of Neuropharmacology, Kerman University of Medical Sciences, Kerman, Iran
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5
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Cleves AE, Jain AN. Quantitative surface field analysis: learning causal models to predict ligand binding affinity and pose. J Comput Aided Mol Des 2018; 32:731-757. [PMID: 29934750 PMCID: PMC6096883 DOI: 10.1007/s10822-018-0126-x] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/23/2018] [Accepted: 06/14/2018] [Indexed: 12/27/2022]
Abstract
We introduce the QuanSA method for inducing physically meaningful field-based models of ligand binding pockets based on structure-activity data alone. The method is closely related to the QMOD approach, substituting a learned scoring field for a pocket constructed of molecular fragments. The problem of mutual ligand alignment is addressed in a general way, and optimal model parameters and ligand poses are identified through multiple-instance machine learning. We provide algorithmic details along with performance results on sixteen structure-activity data sets covering many pharmaceutically relevant targets. In particular, we show how models initially induced from small data sets can extrapolatively identify potent new ligands with novel underlying scaffolds with very high specificity. Further, we show that combining predictions from QuanSA models with those from physics-based simulation approaches is synergistic. QuanSA predictions yield binding affinities, explicit estimates of ligand strain, associated ligand pose families, and estimates of structural novelty and confidence. The method is applicable for fine-grained lead optimization as well as potent new lead identification.
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Affiliation(s)
- Ann E Cleves
- Helen Diller Family Comprehensive Cancer Center, University of California, San Francisco, USA
| | - Ajay N Jain
- Department of Bioengineering and Therapeutic Sciences, University of California, San Francisco, USA.
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6
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Lee BC, Moon BS, Park HS, Jung JH, Park HS, Park DD, de Candia M, Denora N, Altomare CD, Kim SE. The position of fluorine in CP-118,954 affects AChE inhibition potency and PET imaging quantification for AChE expression in the rat brain. Eur J Pharm Sci 2017; 109:209-216. [PMID: 28818531 DOI: 10.1016/j.ejps.2017.08.008] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/20/2017] [Revised: 07/21/2017] [Accepted: 08/14/2017] [Indexed: 10/19/2022]
Abstract
The in vitro inhibition potency against acetylcholinesterase (AChE) of fluorinated derivatives of CP-118,954 (1) has been shown to depend upon the position of aromatic fluorine (F) substitution on the N-benzyl moiety. Indeed, the meta-F-substituted compound 3 (IC50=1.4nM) shows similar potency with the parent compound 1 (IC50=1.2nM), whereas the ortho-F derivative 2 (IC50=3.2nM) and para-F derivative 4 (IC50=10.8nM) were found to be less potent AChE inhibitors. A comparative in vivo microdialysis study in rats showed that 3 has the strongest effect on the neuropharmacological properties as AChE inhibitor. For PET imaging studies, a radiolabeled ligand ([18F]3) was synthesized through nucleophilic aromatic substitution reaction of diaryliodonium salt-based aldehyde precursor followed by reductive alkylation in a two-step radiolabeling procedure with 11.5 ± 1.2% (n=24, non-decay corrected) radiochemical yield and over 99% radiochemical purity. In a comparative PET imaging study of the three 18F-containing derivatives of CP-118,954 ([18F]2-4), [18F]3 showed the highest radioactivity in the AChE-rich region of normal rat brain which visually reflected the in vitro AChE-binding affinity of 3. These findings support [18F]3 as a promising AChE-targeted PET imaging ligand for the assessment of cholinergic activity into the brain, providing also insights into the AChE ligand disposition, which depends upon the position of the aromatic fluorine in the benzyl moiety.
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Affiliation(s)
- Byung Chul Lee
- Department of Nuclear Medicine, Seoul National University Bundang Hospital, Seoul National University College of Medicine, Seongnam 13620, Republic of Korea; Center for Nanomolecular Imaging and Innovative Drug Development, Advanced Institutes of Convergence Technology, Suwon 16229, Republic of Korea
| | - Byung Seok Moon
- Department of Nuclear Medicine, Seoul National University Bundang Hospital, Seoul National University College of Medicine, Seongnam 13620, Republic of Korea
| | - Hyun Soo Park
- Department of Nuclear Medicine, Seoul National University Bundang Hospital, Seoul National University College of Medicine, Seongnam 13620, Republic of Korea
| | - Jae Ho Jung
- Department of Nuclear Medicine, Seoul National University Bundang Hospital, Seoul National University College of Medicine, Seongnam 13620, Republic of Korea
| | - Hyun Sik Park
- Department of Nuclear Medicine, Seoul National University Bundang Hospital, Seoul National University College of Medicine, Seongnam 13620, Republic of Korea
| | - Do Dam Park
- Department of Nuclear Medicine, Seoul National University Bundang Hospital, Seoul National University College of Medicine, Seongnam 13620, Republic of Korea
| | - Modesto de Candia
- Department of Pharmacy-Drug Sciences, University of Bari Aldo Moro, Via E. Orabona 4, 70125 Bari, Italy
| | - Nunzio Denora
- Department of Pharmacy-Drug Sciences, University of Bari Aldo Moro, Via E. Orabona 4, 70125 Bari, Italy
| | - Cosimo D Altomare
- Department of Pharmacy-Drug Sciences, University of Bari Aldo Moro, Via E. Orabona 4, 70125 Bari, Italy
| | - Sang Eun Kim
- Department of Nuclear Medicine, Seoul National University Bundang Hospital, Seoul National University College of Medicine, Seongnam 13620, Republic of Korea; Center for Nanomolecular Imaging and Innovative Drug Development, Advanced Institutes of Convergence Technology, Suwon 16229, Republic of Korea; Department of Transdisciplinary Studies, Graduate School of Convergence Science and Technology, Seoul National University, Seoul 08826, Republic of Korea.
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7
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Singh M, Kaur M, Chadha N, Silakari O. Hybrids: a new paradigm to treat Alzheimer’s disease. Mol Divers 2015; 20:271-97. [DOI: 10.1007/s11030-015-9628-9] [Citation(s) in RCA: 47] [Impact Index Per Article: 5.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/01/2015] [Accepted: 07/29/2015] [Indexed: 12/19/2022]
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Di Pietro O, Pérez-Areales FJ, Juárez-Jiménez J, Espargaró A, Clos MV, Pérez B, Lavilla R, Sabaté R, Luque FJ, Muñoz-Torrero D. Tetrahydrobenzo[h][1,6]naphthyridine-6-chlorotacrine hybrids as a new family of anti-Alzheimer agents targeting β-amyloid, tau, and cholinesterase pathologies. Eur J Med Chem 2014; 84:107-17. [DOI: 10.1016/j.ejmech.2014.07.021] [Citation(s) in RCA: 47] [Impact Index Per Article: 4.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/04/2014] [Revised: 06/18/2014] [Accepted: 07/06/2014] [Indexed: 11/28/2022]
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9
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Kikuchi T, Okamura T, Zhang MR, Irie T. PET probes for imaging brain acetylcholinesterase. J Labelled Comp Radiopharm 2013; 56:172-9. [DOI: 10.1002/jlcr.3002] [Citation(s) in RCA: 17] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/27/2012] [Revised: 11/08/2012] [Accepted: 11/08/2012] [Indexed: 12/31/2022]
Affiliation(s)
- Tatsuya Kikuchi
- Probe Research Team, Molecular Probe Program, Molecular Imaging Center; National Institute of Radiological Sciences; Chiba; 263-8555; Japan
| | - Toshimitsu Okamura
- Probe Research Team, Molecular Probe Program, Molecular Imaging Center; National Institute of Radiological Sciences; Chiba; 263-8555; Japan
| | - Ming-Rong Zhang
- Probe Research Team, Molecular Probe Program, Molecular Imaging Center; National Institute of Radiological Sciences; Chiba; 263-8555; Japan
| | - Toshiaki Irie
- Probe Research Team, Molecular Probe Program, Molecular Imaging Center; National Institute of Radiological Sciences; Chiba; 263-8555; Japan
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10
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A review on cholinesterase inhibitors for Alzheimer’s disease. Arch Pharm Res 2013; 36:375-99. [DOI: 10.1007/s12272-013-0036-3] [Citation(s) in RCA: 355] [Impact Index Per Article: 32.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/01/2012] [Accepted: 02/05/2013] [Indexed: 12/25/2022]
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Yan A, Wang K. Quantitative structure and bioactivity relationship study on human acetylcholinesterase inhibitors. Bioorg Med Chem Lett 2012; 22:3336-42. [DOI: 10.1016/j.bmcl.2012.02.108] [Citation(s) in RCA: 28] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/02/2012] [Revised: 02/15/2012] [Accepted: 02/27/2012] [Indexed: 11/29/2022]
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12
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Anand P, Singh B. Synthesis and evaluation of novel 4-[(3H,3aH,6aH)-3-phenyl)-4,6-dioxo-2-phenyldihydro-2H-pyrrolo[3,4-d]isoxazol-5(3H,6H,6aH)-yl]benzoic acid derivatives as potent acetylcholinesterase inhibitors and anti-amnestic agents. Bioorg Med Chem 2012; 20:521-30. [DOI: 10.1016/j.bmc.2011.05.027] [Citation(s) in RCA: 24] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/17/2011] [Revised: 05/16/2011] [Accepted: 05/17/2011] [Indexed: 11/27/2022]
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Binding of 2-[18F]fluoro-CP-118,954 to mouse acetylcholinesterase: microPET and ex vivo Cerenkov luminescence imaging studies. Nucl Med Biol 2011; 38:541-7. [DOI: 10.1016/j.nucmedbio.2010.11.010] [Citation(s) in RCA: 11] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/12/2010] [Revised: 11/13/2010] [Accepted: 11/28/2010] [Indexed: 11/17/2022]
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14
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Araújo JQ, de Brito MA, Hoelz LVB, de Alencastro RB, Castro HC, Rodrigues CR, Albuquerque MG. Receptor-dependent (RD) 3D-QSAR approach of a series of benzylpiperidine inhibitors of human acetylcholinesterase (HuAChE). Eur J Med Chem 2011; 46:39-51. [DOI: 10.1016/j.ejmech.2010.10.009] [Citation(s) in RCA: 22] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/29/2010] [Revised: 09/09/2010] [Accepted: 10/10/2010] [Indexed: 11/27/2022]
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Lv W, Xue Y. Prediction of acetylcholinesterase inhibitors and characterization of correlative molecular descriptors by machine learning methods. Eur J Med Chem 2010; 45:1167-72. [DOI: 10.1016/j.ejmech.2009.12.038] [Citation(s) in RCA: 25] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/02/2009] [Revised: 12/15/2009] [Accepted: 12/17/2009] [Indexed: 11/28/2022]
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Ul-Haq Z, Mahmood U, Jehangir B. Ligand-based 3D-QSAR studies of physostigmine analogues as acetylcholinesterase inhibitors. Chem Biol Drug Des 2009; 74:571-81. [PMID: 19843075 DOI: 10.1111/j.1747-0285.2009.00897.x] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Abstract
Natural alkaloid Physostigmine is one of the most potent pseudo-irreversible inhibitor of Acetylcholinesterase. It was found to accelerate long-term memory process, but due to its short half life and variable bioavailability, has inconsistent clinical efficacy. 3D-QSAR studies based on the comparative molecular field analysis and comparative molecular similarity indices analysis were applied to a set of 40 Physostigmine derivatives which are divided into two classes: A and B. The study was conducted to obtain a highly reliable and extensive dynamic QSAR model based on alignment procedure with co-crystallized Ganstigmine as template. The strategy yielded significant 3D-QSAR models with the cross-validated q(2) values 0.762 and 0.754 for comparative molecular field analysis and comparative molecular similarity indices analysis, respectively. Resulted models were validated by external set of eight compounds yielding high correlation coefficient r(2) values of 0.730 and 0.720 for comparative molecular field analysis and comparative molecular similarity indices analysis, respectively. Furthermore, the analysis of comparative molecular field analysis and comparative molecular similarity indices analysis contour maps within the active site of AChE were conducted in order to understand the interactions between the receptor and the Physostigmine derivatives. This study will facilitate the rational design of more potent Physostigmine compounds which might have better activity and reduce toxicity for the treatment of Alzheimer disease.
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Affiliation(s)
- Zaheer Ul-Haq
- Dr. Panjwani Center for Molecular Medicine and Drug Research, International Center for Chemical and Biological Sciences, University of Karachi, Karachi 75270, Pakistan.
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Lee I, Choe YS, Ryu EK, Choi BW, Choi JY, Choi Y, Lee KH, Kim BT. Synthesis and evaluation of radioiodine-labelled CP-118,954 for the in-vivo imaging of acetylcholinesterase. Nucl Med Commun 2007; 28:561-6. [PMID: 17538398 DOI: 10.1097/mnm.0b013e328194f1f7] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/27/2022]
Abstract
OBJECTIVES Alzheimer's disease (AD) is characterized by reduced acetylcholinesterase (AChE) activity in the post-mortem tissues of AD patients. Therefore, AChE has been an attractive target for the diagnosis of AD. In the present study, 5,7-dihydro-3-[2-(1-(phenylmethyl)-4-piperidinyl)ethyl]-6H-pyrrolo[3,2-f]-1,2-benzisoxazol-6-one (CP-118,954), a potent AChE inhibitor, was labelled with radioiodine and evaluated as an AChE imaging agent for SPECT. METHODS Radioiodine-labelled CP-118,954 was prepared from CP-144,885 and [(125)I]iodobenzyl bromide, and anti-AChE activities of iodine-substituted CP-118,954 were measured. Metabolism studies were carried out in samples of blood and whole brain of mice injected with 2-[(123)I]iodo-CP-118,954 ((123)I-1). Tissue distribution studies were also performed in mice injected with I-1, and samples of blood, thyroid, stomach, and brain tissue (cerebellum, striatum and cortex) were removed, weighed and counted. RESULTS Of the ligands, 2-iodo-CP-118,954 exhibited higher binding affinity for AChE (IC50=24 nM) than the other positional isomers. 2-[(125)I]Iodo-CP-118,954 was found to have a lipophilicity (log P=2.1) favouring brain permeability and metabolic stability in mouse brain, but a marginal target (striatum) to non-target (cerebellum) uptake ratio (1.1) in mouse brain. CONCLUSION This result demonstrates that 2-[(125)I]iodo-CP-118,954 may be unsuitable for AChE imaging. These findings suggest that radioligands suitable for AChE imaging should have not only a specific structure but also a sub-nanomolar to low nanomolar IC50.
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Affiliation(s)
- Iljung Lee
- Department of Nuclear Medicine, Samsung Medical Center, Sungkyunkwan University School of Medicine, 50 Ilwon-dong, Kangnam-ku, Seoul 135-710, Korea
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Lee SY, Choe YS, Ryu EK, Iimura Y, Choi Y, Lee KH, Kim BT. Is subnanomolar binding affinity required for the in vivo imaging of acetylcholinesterase? Studies on 18F-labeled G379. Nucl Med Biol 2006; 33:91-4. [PMID: 16459263 DOI: 10.1016/j.nucmedbio.2005.10.003] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/05/2005] [Revised: 09/27/2005] [Accepted: 10/03/2005] [Indexed: 11/26/2022]
Abstract
Acetylcholinesterase (AChE) is an important cholinergic marker of Alzheimer's disease (AD) and shows reduced activity in postmortem AD brain tissues. 1-(4-Fluorobenzyl)-4-[(5,6-dimethoxy-1-oxoindan-2-fluoro-2-yl)methyl]piperidine (G379, ), an AChE inhibitor with a subnanomolar IC(50) (0.56 nM), was prepared as a (18)F-labeled radioligand ([(18)F]) and evaluated in mice. Metabolism studies of [(18)F] showed no metabolites in the mouse brain. Tissue distribution studies demonstrated its uniform regional distribution in the mouse brain, suggesting that this radioligand is not suitable for the in vivo imaging of AChE. This result along with reports on radiolabeled N-benzylpiperidine lactam benzisoxazole (IC(50) < 1 nM) and other radiolabeled benzylpiperidine derivatives (IC(50) > 1 nM) suggested that a subnanomolar IC(50) may not be the only important factor in determining the suitability of a radioligand for in vivo studies of AChE.
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Affiliation(s)
- Sang-Yoon Lee
- Department of Nuclear Medicine, Samsung Medical Center, Sungkyunkwan University School of Medicine, Seoul, South Korea
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Ryu EK, Choe YS, Park EY, Paik JY, Kim YR, Lee KH, Choi Y, Kim SE, Kim BT. Synthesis and evaluation of 2-[18F]fluoro-CP-118,954 for the in vivo mapping of acetylcholinesterase. Nucl Med Biol 2005; 32:185-91. [PMID: 15721764 DOI: 10.1016/j.nucmedbio.2004.09.006] [Citation(s) in RCA: 14] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/30/2004] [Revised: 09/13/2004] [Accepted: 09/17/2004] [Indexed: 10/25/2022]
Abstract
5,7-Dihydro-3-[2-[1-(2-fluorobenzyl)-4-piperidinyl]ethyl]-6H-pyrrolo[3,2,f]-1,2-benzisoxazol-6-one (2-flouro-CP-118,954; 1), a potent acetylcholinesterase (AChE) inhibitor, was prepared as a radioligand by reductive alkylation of CP-144,885 the debenzylated form of CP 118,954, with 2-[18F]fluorobenzaldehyde. The decay-corrected radiochemical yield was 25-30% and the effective specific activity was 41-53 GBq/micromol. Tissue distribution studies of 2-[18F]fluoro-CP-118,954 ([18F]1) in mice showed that the regional brain distribution correlated well with the known density of AChE in the mouse brain. A high level of uptake in the striatum was also shown at all time points in the olfactory tubercle, which is known to have dopaminergic neurons. Blocking studies showed that radioligand uptake in all brain regions was not altered by either the dopamine receptor antagonists or the sigma receptor agonist. On the other hand, radioligand uptake in both the striatum and the olfactory tubercle was significantly blocked (80%) by ligand 1. The low level of bone uptake over time suggested that [18F]1 underwent little in vivo metabolic defluorination. The lack of metabolite formation in the mouse brain indicated that the regional distribution was attributed to [18F]1. These results demonstrated that [18F]1 binds specifically and selectively to AChE in mice and appears to be a suitable radioligand for the in vivo mapping of AChE.
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Affiliation(s)
- Eun Kyoung Ryu
- Department of Nuclear Medicine, Samsung Medical Center, Sungkyunkwan University School of Medicine, 135-710 Seoul, Republic of Korea
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Guo J, Hurley MM, Wright JB, Lushington GH. A docking score function for estimating ligand-protein interactions: application to acetylcholinesterase inhibition. J Med Chem 2004; 47:5492-500. [PMID: 15481986 DOI: 10.1021/jm049695v] [Citation(s) in RCA: 39] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Abstract
Acetylcholinesterase (AChE) inhibition is an important research topic because of its wide range of associated health implications. A receptor-specific scoring function was developed herein for predicting binding affinities for human AChE (huAChE) inhibitors. This method entails a statistically trained weighted sum of electrostatic and van der Waals (VDW) interactions between ligands and the receptor residues. Within the 53 ligand training set, a strong correlation was found (R2 = 0.89) between computed and experimental inhibition constants. Leave-one-out cross-validation indicated high predictive power (Q2 = 0.72), and analysis of a separate 16-compound test set also produced very good correlation with experiment (R2 = 0.69). Scoring function analysis has permitted identification and characterization of important ligand-receptor interactions, producing a list of those residues making the most important electrostatic and VDW contributions within the main active site, gorge area, acyl binding pocket, and periferal site. These analyses are consistent with X-ray crystallographic and site-directed mutagenesis studies.
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Affiliation(s)
- Jianxin Guo
- Molecular Graphics and Modeling Lab, University of Kansas, Lawrence, Kansas 66045, USA
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Lee SY, Choe YS, Kim YR, Paik JY, Choi BW, Kim SE, Lee KH, Choi Y, Kim BT. Synthesis and evaluation of 5,7-dihydro-3-[2-[1-(4-[18F]-fluorobenzyl)-4-piperidinyl]ethyl]-6H-pyrrolo[3,2-f]-1,2-benzisoxazol-6-one for in vivo mapping of acetylcholinesterase*. Nucl Med Commun 2004; 25:591-6. [PMID: 15167519 DOI: 10.1097/01.mnm.0000126629.09543.1d] [Citation(s) in RCA: 13] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/26/2022]
Abstract
OBJECTIVES Acetylcholinesterase (AChE) is an important cholinergic marker for the diagnosis of Alzheimer's disease (AD). A recent study has demonstrated that C-labelled 5,7-dihydro-7-methyl-3-[2-[1-(phenylmethyl)-4-piperidinyl]ethyl]-6H-pyrrolo[3,2-f]-1,2-benzisoxazol-6-one (CP-126,998) shows promising results. The demethylated form of this ligand (CP-118,954) is a more potent and selective inhibitor than CP-126,998. In this study, therefore, CP-118,954 was labelled with F and evaluated for the in vivo mapping of AChE. METHODS The 4-fluoro (1). and 2-fluoro (2). derivatives of CP-118,954 were synthesized from 4-methyl-3-nitroanisole in 11 steps. Their in vitro binding affinities to AChE were measured using Ellman's method. The preparation of [F]-1 was carried out by reductive alkylation of the piperidine precursor with 4-[F]-fluorobenzaldehyde, followed by high-performance liquid chromatography (HPLC) purification. In vitro autoradiography was performed by incubating rat brain coronal slices with [F]-1. Tissue distribution studies were performed in mouse brain and the data were expressed as the percentage of the injected dose per gram of tissue (%ID x g). RESULTS Two fluorine-substituted AChE inhibitors were synthesized and their in vitro binding data showed that the 4-fluoro and 2-fluoro derivatives (1 and 2) had similar or superior binding affinity to that of the unsubstituted ligand, CP-118,954. The F-labelled ligand was synthesized in 20-35% radiochemical yield (EOS) and with high effective specific activity (36-42 GBq x micromol). Autoradiography showed high uptake of [F]-1 in the striatum and this striatal uptake was completely inhibited by the unlabelled ligand 1. Tissue distribution studies demonstrated that high radioactivity was accumulated in the striatum, an AChE-rich region. CONCLUSIONS This study demonstrates that [F]-1 may hold promise as a radioligand for the in vivo mapping of AChE.
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Affiliation(s)
- Sang-Yoon Lee
- Department of Nuclear Medicine, Samsung Medical Center, Sungkyunkwan University School of Medicine, Seoul, Korea
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Bencherif B, Endres CJ, Musachio JL, Villalobos A, Hilton J, Scheffel U, Dannals RF, Williams S, Frost JJ. PET imaging of brain acetylcholinesterase using [11C]CP-126,998, a brain selective enzyme inhibitor. Synapse 2002; 45:1-9. [PMID: 12112408 DOI: 10.1002/syn.10072] [Citation(s) in RCA: 28] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/09/2022]
Abstract
PET and [(11)C]CP-126,998, an N-benzylpiperidinebenzisoxazole, were used to image brain acetylcholinesterase (AChE) distribution in healthy controls before and after administration of 5 mg donepezil p.o., a reversible AChE inhibitor. Logan plots were used to compute distribution volumes (V(T)). The V(T) of [(11)C]CP-126,998 was highest in the basal ganglia and cerebellum and lowest in the cerebral cortex, thalamus, amygdala, and hippocampus. The regional V(T) values correlated well with AChE concentration measured in vitro. Donepezil, given 4 h before PET scanning, induced a substantial inhibition of [(11)C]CP-126,998 binding (43-62%) in all brain regions when compared to the baseline PET study. The results of this study indicate that PET imaging of [(11)C]CP-126,998 may be useful in quantifying the distribution of regional brain AChE. This new PET radiotracer may potentially be employed in the diagnosis and treatment of patients with disorders of cholinergic neurotransmission, such as Alzheimer's disease.
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Affiliation(s)
- B Bencherif
- Department of Radiology, The Johns Hopkins University School of Medicine, Baltimore, Maryland 21287, USA
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23
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Musachio JL, Flesher JE, Scheffel UA, Rauseo P, Hilton J, Mathews WB, Ravert HT, Dannals RF, Frost JJ. Radiosynthesis and mouse brain distribution studies of [11C] CP-126,998: a PET ligand for in vivo study of acetylcholinesterase. Nucl Med Biol 2002; 29:547-52. [PMID: 12088724 DOI: 10.1016/s0969-8051(02)00299-8] [Citation(s) in RCA: 16] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/27/2022]
Abstract
The selective, reversible acetylcholinesterase inhibitor 5,7-Dihydro-7-methyl-3- [2-[1-(phenylmethyl]-4-piperidinyl]ethyl]-6H-pyrrolo[3,2-f]-1,2-benzisoxazol3-6-one (CP-126,998) was labeled with C-11 iodomethane via base-promoted alkylation of the lactam nitrogen. [11C] CP-126,998 was synthesized in good radiochemical yield (13-29% non-decay corrected) and high specific radioactivity (177-418 GBq/micromol). In vivo mouse biodistribution studies reveal [11C] CP-126,998 to localize preferentially in striatal tissue, a region known to be rich in acetylcholinesterase. Competitive blocking studies using a variety of acetylcholinesterase inhibitors (diisopropylfluorophosphate, tacrine, CP-118,954) verified the specificity of the PET radiotracer for brain acetylcholinesterase.
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Affiliation(s)
- John L Musachio
- Johns Hopkins University School of Medicine, Department of Radiology, Division of Nuclear Medicine, Baltimore, MD 21287, USA.
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Barril X, Orozco M, Luque FJ. Predicting relative binding free energies of tacrine-huperzine A hybrids as inhibitors of acetylcholinesterase. J Med Chem 1999; 42:5110-9. [PMID: 10602696 DOI: 10.1021/jm990371u] [Citation(s) in RCA: 32] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Abstract
The binding of the 9-methyl derivative of tacrine-huperzine A hybrid to Torpedo californica acetylcholinesterase (AChE) has been studied by computational methods. Molecular dynamics simulations have been performed for the AChE-drug complex considering two different ionization states of the protein and two different orientations of the drug in the binding pocket, which were chosen from a previous screening procedure. Analysis of structural fluctuations and of the pattern of interactions between drug and enzyme clearly favor one binding mode for the tacrine-huperzine A hydrid, which mixes effectively some of the binding features of tacrine and huperzine A. The differences in inhibitory activity for a series of related derivatives have been successfully predicted by free energy calculations, which reinforces the confidence in the binding mode and its usefulness for molecular modeling studies. The same techniques have been used to make de novo predictions for a new 3-fluoro-9-ethyl derivative, which can be used to verify a posteriori the goodness of the binding mode. Finally, we have also investigated the effect of replacing Phe300 in the Torpedo californica enzyme by Tyr, which is present in the human AChE. The results indicate that the Phe330-->Tyr mutation is expected to have little effect on the binding affinities. Overall, the whole of results supports the validity of the putative binding model to explain the binding of tacrine-huperzine A hybrids to AChE.
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Affiliation(s)
- X Barril
- Departament de Fisicoquímica, Facultat de Farmàcia, Universitat de Barcelona, Avgda. Diagonal 643, 08028 Barcelona, Spain
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Carlier PR, Chow ES, Han Y, Liu J, El Yazal J, Pang YP. Heterodimeric tacrine-based acetylcholinesterase inhibitors: investigating ligand-peripheral site interactions. J Med Chem 1999; 42:4225-31. [PMID: 10514292 DOI: 10.1021/jm990224w] [Citation(s) in RCA: 109] [Impact Index Per Article: 4.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Abstract
Dimeric acetylcholinesterase (AChE) inhibitors containing a single 9-amino-1,2,3,4-tetrahydroacridine (tacrine) unit were constructed in an effort to further delineate structural requirements for optimal binding to the AChE peripheral site. Basic amines of differing hydrophobicity were selected as peripheral site ligands, and in each case, improvements in inhibitory potency and selectivity were seen relative to tacrine itself. AChE IC(50) values of the optimum dimers decrease significantly as the peripheral site ligand was permuted in the series ammonia > dimethylamine > 4-aminopyridine > 4-aminoquinoline > tacrine. Calculated desolvation free energies of the optimum dimers match the trend in IC(50) values, suggesting the importance of ligand hydrophobicity for effective cation-pi interaction with the peripheral site.
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Affiliation(s)
- P R Carlier
- Department of Chemistry, Hong Kong University of Science and Technology, Clear Water Bay, Kowloon, Hong Kong.
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Bernard P, Kireev DB, Chrétien JR, Fortier PL, Coppet L. Automated docking of 82 N-benzylpiperidine derivatives to mouse acetylcholinesterase and comparative molecular field analysis with 'natural' alignment. J Comput Aided Mol Des 1999; 13:355-71. [PMID: 10425601 DOI: 10.1023/a:1008071118697] [Citation(s) in RCA: 22] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/12/2022]
Abstract
Automated docking and three-dimensional Quantitative Structure-Activity Relationship studies (3D QSAR) were performed for a series of 82 reversible, competitive and selective acetylcholinesterase (AChE) inhibitors. The suggested automated docking technique, making use of constraints taken from experimental crystallographic data, allowed to dock all the 82 substituted N-benzylpiperidines to the crystal structure of mouse AChE, because of short computational times. A 3D QSAR model was then established using the CoMFA method. In contrast to conventional CoMFA studies, the compounds were not fitted to a reference molecule but taken in their 'natural' alignment obtained by the docking study. The established and validated CoMFA model was then applied to another series of 29 N-benzylpiperidine derivatives whose AChE inhibitory activity data were measured under different experimental conditions. A good correlation between predicted and experimental activity data shows that the model can be extended to AChE inhibitory activity data measured on another acetylcholinesterase and/or at different incubation times and pH level.
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Affiliation(s)
- P Bernard
- Laboratoire de Chimiométrie, Université d'Orléans, France
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27
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Kryger G, Silman I, Sussman JL. Structure of acetylcholinesterase complexed with E2020 (Aricept): implications for the design of new anti-Alzheimer drugs. Structure 1999; 7:297-307. [PMID: 10368299 DOI: 10.1016/s0969-2126(99)80040-9] [Citation(s) in RCA: 556] [Impact Index Per Article: 22.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/01/2022]
Abstract
BACKGROUND Several cholinesterase inhibitors are either being utilized for symptomatic treatment of Alzheimer's disease or are in advanced clinical trials. E2020, marketed as Aricept, is a member of a large family of N-benzylpiperidine-based acetylcholinesterase (AChE) inhibitors developed, synthesized and evaluated by the Eisai Company in Japan. These inhibitors were designed on the basis of QSAR studies, prior to elucidation of the three-dimensional structure of Torpedo californica AChE (TcAChE). It significantly enhances performance in animal models of cholinergic hypofunction and has a high affinity for AChE, binding to both electric eel and mouse AChE in the nanomolar range. RESULTS Our experimental structure of the E2020-TcAChE complex pinpoints specific interactions responsible for the high affinity and selectivity demonstrated previously. It shows that E2020 has a unique orientation along the active-site gorge, extending from the anionic subsite of the active site, at the bottom, to the peripheral anionic site, at the top, via aromatic stacking interactions with conserved aromatic acid residues. E2020 does not, however, interact directly with either the catalytic triad or the 'oxyanion hole', but only indirectly via solvent molecules. CONCLUSIONS Our study shows, a posteriori, that the design of E2020 took advantage of several important features of the active-site gorge of AChE to produce a drug with both high affinity for AChE and a high degree of selectivity for AChE versus butyrylcholinesterase (BChE). It also delineates voids within the gorge that are not occupied by E2020 and could provide sites for potential modification of E2020 to produce drugs with improved pharmacological profiles.
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Affiliation(s)
- G Kryger
- Department of Structural Biology, Weizmann Institute of Science, Rehovot 76100, Israel.
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28
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Brown-Proctor C, Snyder SE, Sherman PS, Kilbourn MR. Synthesis and evaluation of 6-[11C]methoxy-3-[2-[1-(phenylmethyl)-4-piperidinyl]ethyl]-1,2- benzisoxazole as an in vivo radioligand for acetylcholinesterase. Nucl Med Biol 1999; 26:99-103. [PMID: 10096508 DOI: 10.1016/s0969-8051(98)00078-x] [Citation(s) in RCA: 17] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/25/2022]
Abstract
6-Methoxy-3-[2-[1-(phenylmethyl)-4-piperidinyl]ethyl]-1,2-benzisoxazole is a high affinity (K(i) = 8.2 nM) reversible inhibitor of acetylcholinesterase (AChE). The carbon-11 labeled form was prepared in high (>97%) radiochemical purity and with specific activities of 37+/-20 GBq/micromol at end of synthesis, by the alkylation of the desmethyl precursor with [11C]methyl trifluoromethanesulfonate in N,N-dimethyl-formamide at room temperature. In vivo studies in mice demonstrated good blood brain permeability but essentially uniform regional brain distribution. Thus, despite in vitro and in vivo activity as an AChE inhibitor, 6-[11C]methoxy-3-[2-[1-(phenylmethyl)-4-piperidinyl]ethyl]-1,2-benzis oxa zole does not appear to be a good candidate for in vivo imaging studies of AChE in the mammalian brain.
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Affiliation(s)
- C Brown-Proctor
- Department of Internal Medicine, University of Michigan Medical Center, Ann Arbor 48109-0552, USA
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Pang YP, Quiram P, Jelacic T, Hong F, Brimijoin S. Highly potent, selective, and low cost bis-tetrahydroaminacrine inhibitors of acetylcholinesterase. Steps toward novel drugs for treating Alzheimer's disease. J Biol Chem 1996; 271:23646-9. [PMID: 8798583 DOI: 10.1074/jbc.271.39.23646] [Citation(s) in RCA: 288] [Impact Index Per Article: 10.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/02/2023] Open
Abstract
We report highly potent, selective, and low cost bifunctional acetylcholinesterase (AChE) inhibitors developed by our two-step prototype optimization strategy utilizing computer modeling of ligand docking with target proteins: 1) identify low affinity sites normally missed by x-ray crystallography; and 2) design bifunctional analogs capable of simultaneous binding at the computer-determined low affinity site and the x-ray-identified high affinity site. Applying this strategy to 9-amino-1,2,3,4-tetrahydroacridine (THA), a drug for Alzheimer's disease, we obtained alkylene linked bis-THA analogs. These analogs were up to 10,000-fold more selective and 1,000-fold more potent than THA in inhibiting rat AChE and yet required one simple reaction to synthesize. Additionally, alkylene linked benzyl-THA analogs were developed to examine the specificity of the docking-derived low affinity THA peripheral site in AChE. The present work and our previous computational studies strongly suggest that a low affinity THA peripheral site exists in AChE. This peripheral site provides a structural basis for design of improved cholinesterase ligands for treating Alzheimer's disease and for other health-related purposes.
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Affiliation(s)
- Y P Pang
- Neurochemistry Research, Mayo Foundation for Medical Education and Research, Jacksonville, Florida 32224, USA
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