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Zaidi SA, Katritch V. Structural Characterization of KOR Inactive and Active States for 3D Pharmacology and Drug Discovery. Handb Exp Pharmacol 2021; 271:41-64. [PMID: 33945028 DOI: 10.1007/164_2021_461] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/04/2023]
Abstract
The structure of the human kappa opioid receptor (KOR) in complex with the long-acting antagonist JDTic was solved crystallographically in 2012 and, along with structures of other opioid receptors, revolutionized our understanding of opioid system function and pharmacology. More recently, active state KOR structure was also determined, giving important insights into activation mechanisms of the receptor. In this review, we will discuss how the understanding of atomistic structures of KOR established a key platform for deciphering details of subtype and functional selectivity of KOR-targeting ligands and for discovery of new chemical probes with potentially beneficial pharmacological profiles.
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Affiliation(s)
- Saheem A Zaidi
- Department of Quantitative and Computational Biology, Bridge Institute, USC Michelson Center for Convergent Biosciences, University of Southern California, Los Angeles, CA, USA
| | - Vsevolod Katritch
- Department of Quantitative and Computational Biology, Bridge Institute, USC Michelson Center for Convergent Biosciences, University of Southern California, Los Angeles, CA, USA. .,Department of Chemistry, Bridge Institute, USC Michelson Center for Convergent Biosciences, University of Southern California, Los Angeles, CA, USA.
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2
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Shi Y, Meng F, Liu J, Wang B. In silico modeling and in vitro activity of vitexin and isovitexin against SGLT2. J Theor Comput Chem 2020. [DOI: 10.1142/s0219633619500354] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/18/2022]
Abstract
The homology model of hSGLT2 (human sodium dependent glucose co-transporter 2) was used as a target for diabetes mellitus. Molecular docking and dynamics simulations were carried out on vitexin- and isovitexin-SGLT2 complexes with dapagliflozin as positive control. The results show that both vitexin and isovitexin have weaker binding energies compared to dapagliflozin, indicating that both ligands may exhibit weak anti-diabetic effects through inhibiting SGLT2. The poor binding mode of vitexin and isovitexin may be responsible for their weak anti-diabetic effect. These results are in accordance with the inhibitory activity against hSGLT2 in vitro test with the inhibitory rate 26.3% of vitexin and 11.2% of isovitexin at the dose of 10[Formula: see text][Formula: see text]mol[Formula: see text][Formula: see text][Formula: see text]L[Formula: see text]. The results of calculation and in vitro test may explain the possible inhibiting mechanism of vitexin and isovitexin against SGLT2, and therefore enhance our understanding of the structure-activity relationships of SGLT2 inhibitors.
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Affiliation(s)
- Yongheng Shi
- Shaanxi University of Chinese Medicine, Xianyang 712046, P. R. China
- Key Laboratory of Pharmacodynamics and Material Basis of Chinese Medicine, Shaanxi Administration of Traditional Chinese Medicine, Xianyang 712046, P. R. China
| | - Fancui Meng
- Tianjin Key Laboratory of Molecular Design and Drug Discovery, Tianjin Institute of Pharmaceutical Research, Tianjin 300193, P. R. China
| | - Jiping Liu
- Shaanxi University of Chinese Medicine, Xianyang 712046, P. R. China
- Key Laboratory of Pharmacodynamics and Material Basis of Chinese Medicine, Shaanxi Administration of Traditional Chinese Medicine, Xianyang 712046, P. R. China
| | - Bin Wang
- Key Laboratory of Pharmacodynamics and Material Basis of Chinese Medicine, Shaanxi Administration of Traditional Chinese Medicine, Xianyang 712046, P. R. China
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3
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Balasubramani S, Sabapathi G, Moola AK, Solomon RV, Venuvanalingam P, Bollipo Diana RK. Evaluation of the Leaf Essential Oil from Artemisia vulgaris and Its Larvicidal and Repellent Activity against Dengue Fever Vector Aedes aegypti-An Experimental and Molecular Docking Investigation. ACS Omega 2018; 3:15657-15665. [PMID: 30556010 PMCID: PMC6288777 DOI: 10.1021/acsomega.8b01597] [Citation(s) in RCA: 13] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 07/10/2018] [Accepted: 10/31/2018] [Indexed: 06/09/2023]
Abstract
Aedes aegypti is a mosquito vector that spreads dengue fever and yellow fever worldwide in tropical and subtropical countries. Essential oil isolated from Artemisia vulgaris is found to have larvicidal and repellent action against this vector. The dried leaves were subjected to hydrodistillation using a clevenger-type apparatus for 4 h. The isolated essential oil was analyzed by using gas chromatography-mass spectrometry, and the major insecticidal compounds were identified as α-humulene (0.72%), β-caryophyllene (0.81%), and caryophyllene oxide (15.87%). Larvicidal activity results revealed that the essential oil exposure for 24 h period against the third stage larvae was LC50 = 6.87, LC90 = 59.197 ppm and for the fourth stage larvae LC50 = 4.269, LC90 = 50.363 ppm. Highest mortality rates were observed at 24 h exposure period of third and fourth stages, and the exposed A. aegypti larvae were subjected to histo chemical studies, and the studies revealed that larvae cells got totally damaged (midgut and cortex). The repellent activity results revealed that at 50% concentration of the essential oil showed the highest repellent activity at 60 min protection time against the A. aegypti female mosquitoes. To gain further insights into the insecticidal activity, density functional theory and molecular docking calculations were performed with the active components of this essential oil as the ligand and NS3 protease domain (PDB ID: 2FOM) as a receptor. Molecular docking calculation results show that (E)-β-caryophyllene strongly binds with NS3 protease domain than (Z)-β-caryophyllene, α-humulene, and β-caryophyllene oxide and is the major active component for the insecticidal action. It primarily interacts with the receptor through hydrophobic and ionic forces and using water bridges between the amino acid residues in the binding pocket and (E)-β-caryophyllene.
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Affiliation(s)
- Sundararajan Balasubramani
- Department
of Botany and Theoretical and Computational Chemistry Laboratory,
School of Chemistry, Bharathidasan University, Tiruchirappalli 620024, Tamil Nadu, India
| | - Gopal Sabapathi
- Department
of Botany and Theoretical and Computational Chemistry Laboratory,
School of Chemistry, Bharathidasan University, Tiruchirappalli 620024, Tamil Nadu, India
| | - Anil Kumar Moola
- Department
of Botany and Theoretical and Computational Chemistry Laboratory,
School of Chemistry, Bharathidasan University, Tiruchirappalli 620024, Tamil Nadu, India
| | - Rajadurai Vijay Solomon
- Department
of Chemistry, Madras Christian College (Autonomous), Chennai 600059, Tamil Nadu, India
| | - Ponnambalam Venuvanalingam
- Department
of Botany and Theoretical and Computational Chemistry Laboratory,
School of Chemistry, Bharathidasan University, Tiruchirappalli 620024, Tamil Nadu, India
| | - Ranjitha Kumari Bollipo Diana
- Department
of Botany and Theoretical and Computational Chemistry Laboratory,
School of Chemistry, Bharathidasan University, Tiruchirappalli 620024, Tamil Nadu, India
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4
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Funes M, Garro MF, Tosso RD, Maria AO, Saad JR, Enriz RD. Antinociceptive effect of neo-clerodane diterpenes obtained from Baccharis flabellata. Fitoterapia 2018; 130:94-99. [DOI: 10.1016/j.fitote.2018.08.017] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/02/2018] [Revised: 08/13/2018] [Accepted: 08/22/2018] [Indexed: 10/28/2022]
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Abstract
The Molecular Mechanics Poisson-Boltzmann Surface Area (MMPBSA) approach has been widely applied as an efficient and reliable free energy simulation method to model molecular recognition, such as for protein-ligand binding interactions. In this review, we focus on recent developments and applications of the MMPBSA method. The methodology review covers solvation terms, the entropy term, extensions to membrane proteins and high-speed screening, and new automation toolkits. Recent applications in various important biomedical and chemical fields are also reviewed. We conclude with a few future directions aimed at making MMPBSA a more robust and efficient method.
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Affiliation(s)
- Changhao Wang
- Chemical and Materials Physics Graduate Program, University of California, Irvine, Irvine, CA, United States
- Department of Molecular Biology and Biochemistry, University of California, Irvine, Irvine, CA, United States
- Department of Physics and Astronomy, University of California, Irvine, Irvine, CA, United States
| | - D'Artagnan Greene
- Department of Molecular Biology and Biochemistry, University of California, Irvine, Irvine, CA, United States
| | - Li Xiao
- Department of Molecular Biology and Biochemistry, University of California, Irvine, Irvine, CA, United States
- Department of Biomedical Engineering, University of California, Irvine, Irvine, CA, United States
| | - Ruxi Qi
- Department of Molecular Biology and Biochemistry, University of California, Irvine, Irvine, CA, United States
| | - Ray Luo
- Chemical and Materials Physics Graduate Program, University of California, Irvine, Irvine, CA, United States
- Department of Molecular Biology and Biochemistry, University of California, Irvine, Irvine, CA, United States
- Department of Biomedical Engineering, University of California, Irvine, Irvine, CA, United States
- Department of Chemical Engineering and Materials Science, University of California, Irvine, Irvine, CA, United States
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6
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Chen Z, Dong S, Meng F, Liang Y, Zhang S, Sun J. Insights into the binding of agonist and antagonist to TAS2R16 receptor: a molecular simulation study. Molecular Simulation 2017. [DOI: 10.1080/08927022.2017.1376325] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 10/18/2022]
Affiliation(s)
- Zhirong Chen
- Department of Pharmacology of Chinese Medicine, Beijing University of Chinese Medicine, Beijing, China
| | - Shifen Dong
- Department of Pharmacology of Chinese Medicine, Beijing University of Chinese Medicine, Beijing, China
| | - Fancui Meng
- Tianjin Key Laboratory of Molecular Design and Drug Discovery, Tianjin Institute of Pharmaceutical Research, Tianjin, China
| | - Yaoyue Liang
- Department of Pharmacology of Chinese Medicine, Beijing University of Chinese Medicine, Beijing, China
| | - Shuofeng Zhang
- Department of Pharmacology of Chinese Medicine, Beijing University of Chinese Medicine, Beijing, China
| | - Jianning Sun
- Department of Pharmacology of Chinese Medicine, Beijing University of Chinese Medicine, Beijing, China
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Kurt BZ, Gazioglu I, Dag A, Salmas RE, Kayık G, Durdagi S, Sonmez F. Synthesis, anticholinesterase activity and molecular modeling study of novel carbamate-substituted thymol/carvacrol derivatives. Bioorg Med Chem 2017; 25:1352-63. [DOI: 10.1016/j.bmc.2016.12.037] [Citation(s) in RCA: 35] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/20/2016] [Accepted: 12/22/2016] [Indexed: 12/26/2022]
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8
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Richarz AN, Avramopoulos A, Benfenati E, Gajewicz A, Golbamaki Bakhtyari N, Leonis G, Marchese Robinson RL, Papadopoulos MG, Cronin MT, Puzyn T. Compilation of Data and Modelling of Nanoparticle Interactions and Toxicity in the NanoPUZZLES Project. Adv Exp Med Biol 2017; 947:303-324. [PMID: 28168672 DOI: 10.1007/978-3-319-47754-1_10] [Citation(s) in RCA: 5] [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: 12/12/2022]
Abstract
The particular properties of nanomaterials have led to their rapidly increasing use in diverse fields of application. However, safety assessment is not keeping pace and there are still gaps in the understanding of their hazards. Computational models predicting nanotoxicity, such as (quantitative) structure-activity relationships ((Q)SARs), can contribute to safety evaluation, in line with general efforts to apply alternative methods in chemical risk assessment. Their development is highly dependent on the availability of reliable and high quality experimental data, both regarding the compounds' properties as well as the measured toxic effects. In particular, "nano-QSARs" should take the nano-specific characteristics into account. The information compiled needs to be well organized, quality controlled and standardized. Integrating the data in an overarching, structured data collection aims to (a) organize the data in a way to support modelling, (b) make (meta)data necessary for modelling available, and (c) add value by making a comparison between data from different sources possible.Based on the available data, specific descriptors can be derived to parameterize the nanomaterial-specific structure and physico-chemical properties appropriately. Furthermore, the interactions between nanoparticles and biological systems as well as small molecules, which can lead to modifications of the structure of the active nanoparticles, need to be described and taken into account in the development of models to predict the biological activity and toxicity of nanoparticles. The EU NanoPUZZLES project was part of a global cooperative effort to advance data availability and modelling approaches supporting the characterization and evaluation of nanomaterials.
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Affiliation(s)
- Andrea-Nicole Richarz
- School of Pharmacy and Biomolecular Sciences, Liverpool John Moores University, Liverpool, UK
| | - Aggelos Avramopoulos
- Institute of Biology, Pharmaceutical Chemistry and Biotechnology, National Hellenic Research Foundation, Athens, Greece
| | - Emilio Benfenati
- Laboratory of Environmental Chemistry and Toxicology, Istituto di Ricerche Farmacologiche Mario Negri, Milan, Italy
| | - Agnieszka Gajewicz
- Laboratory of Environmental Chemometrics, Institute for Environmental and Human Health Protection, Faculty of Chemistry, University of Gdańsk, Gdańsk, Poland
| | - Nazanin Golbamaki Bakhtyari
- Laboratory of Environmental Chemistry and Toxicology, Istituto di Ricerche Farmacologiche Mario Negri, Milan, Italy
| | - Georgios Leonis
- Institute of Biology, Pharmaceutical Chemistry and Biotechnology, National Hellenic Research Foundation, Athens, Greece
| | | | - Manthos G Papadopoulos
- Institute of Biology, Pharmaceutical Chemistry and Biotechnology, National Hellenic Research Foundation, Athens, Greece
| | - Mark Td Cronin
- School of Pharmacy and Biomolecular Sciences, Liverpool John Moores University, Liverpool, UK
| | - Tomasz Puzyn
- Laboratory of Environmental Chemometrics, Institute for Environmental and Human Health Protection, Faculty of Chemistry, University of Gdańsk, Gdańsk, Poland
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Mirza SB, Ekhteiari Salmas R, Fatmi MQ, Durdagi S. Discovery of Klotho peptide antagonists against Wnt3 and Wnt3a target proteins using combination of protein engineering, protein-protein docking, peptide docking and molecular dynamics simulations. J Enzyme Inhib Med Chem 2016; 32:84-98. [PMID: 27766889 PMCID: PMC6009926 DOI: 10.1080/14756366.2016.1235569] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/05/2022] Open
Abstract
The Klotho is known as lifespan enhancing protein involved in antagonizing the effect of Wnt proteins. Wnt proteins are stem cell regulators, and uninterrupted exposure of Wnt proteins to the cell can cause stem and progenitor cell senescence, which may lead to aging. Keeping in mind the importance of Klotho in Wnt signaling, in silico approaches have been applied to study the important interactions between Klotho and Wnt3 and Wnt3a (wingless-type mouse mammary tumor virus (MMTV) integration site family members 3 and 3a). The main aim of the study is to identify important residues of the Klotho that help in designing peptides which can act as Wnt antagonists. For this aim, a protein engineering study is performed for Klotho, Wnt3 and Wnt3a. During the theoretical analysis of homology models, unexpected role of number of disulfide bonds and secondary structure elements has been witnessed in case of Wnt3 and Wnt3a proteins. Different in silico experiments were carried out to observe the effect of correct number of disulfide bonds on 3D protein models. For this aim, total of 10 molecular dynamics (MD) simulations were carried out for each system. Based on the protein–protein docking simulations of selected protein models of Klotho with Wnt3 and Wnt3a, different peptides derived from Klotho have been designed. Wnt3 and Wnt3a proteins have three important domains: Index finger, N-terminal domain and a patch of ∼10 residues on the solvent exposed surface of palm domain. Protein–peptide docking of designed peptides of Klotho against three important domains of palmitoylated Wnt3 and Wnt3a yields encouraging results and leads better understanding of the Wnt protein inhibition by proposed Klotho peptides. Further in vitro studies can be carried out to verify effects of novel designed peptides as Wnt antagonists.
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Affiliation(s)
- Shaher Bano Mirza
- a Department of Biophysics, School of Medicine , Bahcesehir University (BAU) , Istanbul , Turkey.,b Department of Biosciences , COMSATS Institute of Information Technology (CIIT) , Islamabad , Pakistan
| | - Ramin Ekhteiari Salmas
- a Department of Biophysics, School of Medicine , Bahcesehir University (BAU) , Istanbul , Turkey
| | - M Qaiser Fatmi
- b Department of Biosciences , COMSATS Institute of Information Technology (CIIT) , Islamabad , Pakistan
| | - Serdar Durdagi
- a Department of Biophysics, School of Medicine , Bahcesehir University (BAU) , Istanbul , Turkey
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10
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Schmitt S, Delamare J, Tirel O, Fillesoye F, Dhilly M, Perrio C. N-[ 18F]-FluoropropylJDTic for κ-opioid receptor PET imaging: Radiosynthesis, pre-clinical evaluation, and metabolic investigation in comparison with parent JDTic. Nucl Med Biol 2016; 44:50-61. [PMID: 27821345 DOI: 10.1016/j.nucmedbio.2016.09.005] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/22/2016] [Revised: 09/07/2016] [Accepted: 09/17/2016] [Indexed: 02/08/2023]
Abstract
INTRODUCTION To image kappa opioid receptor (KOR) for preclinical studies, N-fluoropropylJDTic 9 derived from the best-established KOR antagonist JDTic, was labeled with fluorine-18. METHODS Radiosynthesis of [18F]9 was achieved according to an automated two-step procedure from [18F]-fluoride. Peripheral and cerebral distributions were determined by ex vivo experiments and by PET imaging in mouse. Radiometabolism studies were performed both in vivo in mice and in vitro in mouse and human liver microsomes. Identification of the major metabolic fragmentations was carried out by UPLC-MS analysis of enzymatic cleavage of non-radioactive ligand 9. Microsomal metabolic degradation of parent JDTic was also achieved for comparison. RESULTS The radiotracer [18F]9 was produced after 140±5min total synthesis time (2.2±0.4% not decay corrected radiochemical yield) with a specific activity of 41-89GBq/μmol (1.1-2.4Ci/μmol). Peripheral and regional brain distributions of [18F]9 were consistent with known KOR locations but no significant specific binding in brain was shown. [18F]9 presented a typical hepatobiliary and renal elimination, and was rapidly metabolized. The in vivo and in vitro radiometabolic profiles of [18F]9 were similar. Piperidine 12 was identified as the major metabolic fragment of the non-radioactive ligand 9. JDTic 7 was found to be much more stable than 9. CONCLUSION Although the newly proposed radioligand [18F]9 was concluded to be not suitable for KOR PET imaging due to the formation of brain penetrating radiometabolites, our findings highlight the metabolic stability of JDTic and may help in the design of novel JDTic derivatives for in vivo applications.
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Affiliation(s)
- Sébastien Schmitt
- Normandie Univ, UNICAEN, CEA, CNRS, UMR6301-ISTCT, LDM-TEP, Cyceron, Boulevard Henri Becquerel, 14000, Caen, France
| | - Jérôme Delamare
- Normandie Univ, UNICAEN, CEA, CNRS, UMR6301-ISTCT, LDM-TEP, Cyceron, Boulevard Henri Becquerel, 14000, Caen, France
| | - Olivier Tirel
- Normandie Univ, UNICAEN, CEA, CNRS, UMR6301-ISTCT, LDM-TEP, Cyceron, Boulevard Henri Becquerel, 14000, Caen, France
| | - Fabien Fillesoye
- Normandie Univ, UNICAEN, CEA, CNRS, UMR6301-ISTCT, LDM-TEP, Cyceron, Boulevard Henri Becquerel, 14000, Caen, France
| | - Martine Dhilly
- Normandie Univ, UNICAEN, CEA, CNRS, UMR6301-ISTCT, LDM-TEP, Cyceron, Boulevard Henri Becquerel, 14000, Caen, France
| | - Cécile Perrio
- Normandie Univ, UNICAEN, CEA, CNRS, UMR6301-ISTCT, LDM-TEP, Cyceron, Boulevard Henri Becquerel, 14000, Caen, France.
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Guerrieri E, Bermudez M, Wolber G, Berzetei-Gurske IP, Schmidhammer H, Spetea M. Structural determinants of diphenethylamines for interaction with the κ opioid receptor: Synthesis, pharmacology and molecular modeling studies. Bioorg Med Chem Lett 2016; 26:4769-4774. [PMID: 27567368 DOI: 10.1016/j.bmcl.2016.08.031] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/01/2016] [Revised: 08/10/2016] [Accepted: 08/11/2016] [Indexed: 10/21/2022]
Abstract
The κ opioid (KOP) receptor crystal structure in an inactive state offers nowadays a valuable platform for inquiry into receptor function. We describe the synthesis, pharmacological evaluation and docking calculations of KOP receptor ligands from the class of diphenethylamines using an active-like structure of the KOP receptor attained by molecular dynamics simulations. The structure-activity relationships derived from computational studies was in accordance with pharmacological activities of targeted diphenethylamines at the KOP receptor established by competition binding and G protein activation in vitro assays. Our analysis identified that agonist binding results in breaking of the Arg156-Thr273 hydrogen bond, which stabilizes the inactive receptor conformation, and a crucial hydrogen bond with His291 is formed. Compounds with a phenolic 4-hydroxy group do not form the hydrogen bond with His291, an important residue for KOP affinity and agonist activity. The size of the N-substituent hosted by the hydrophobic pocket formed by Val108, Ile316 and Tyr320 considerably influences binding and selectivity, with the n-alkyl size limit being five carbon atoms, while bulky substituents turn KOP agonists in antagonists. Thus, combination of experimental and molecular modeling strategies provides an initial framework for understanding the structural features of diphenethylamines that are essential to promote binding affinity and selectivity for the KOP receptor, and may be involved in transduction of the ligand binding event into molecular changes, ultimately leading to receptor activation.
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Affiliation(s)
- Elena Guerrieri
- Department of Pharmaceutical Chemistry, Institute of Pharmacy and Center for Molecular Biosciences Innsbruck (CMBI), University of Innsbruck, Innrain 80-82, A-6020 Innsbruck, Austria
| | - Marcel Bermudez
- Institute of Pharmacy, Freie Universität Berlin, D-14195 Berlin, Germany
| | - Gerhard Wolber
- Institute of Pharmacy, Freie Universität Berlin, D-14195 Berlin, Germany
| | - Ilona P Berzetei-Gurske
- Biosciences Division, SRI International, 333 Ravenswood Avenue, Menlo Park, CA 94025, United States
| | - Helmut Schmidhammer
- Department of Pharmaceutical Chemistry, Institute of Pharmacy and Center for Molecular Biosciences Innsbruck (CMBI), University of Innsbruck, Innrain 80-82, A-6020 Innsbruck, Austria
| | - Mariana Spetea
- Department of Pharmaceutical Chemistry, Institute of Pharmacy and Center for Molecular Biosciences Innsbruck (CMBI), University of Innsbruck, Innrain 80-82, A-6020 Innsbruck, Austria.
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12
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Ekhteiari Salmas R, Unlu A, Bektaş M, Yurtsever M, Mestanoglu M, Durdagi S. Virtual screening of small molecules databases for discovery of novel PARP-1 inhibitors: combination of in silico and in vitro studies. J Biomol Struct Dyn 2016; 35:1899-1915. [DOI: 10.1080/07391102.2016.1199328] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/21/2022]
Affiliation(s)
| | - Ayhan Unlu
- Faculty of Medicine, Department of Biophysics, Trakya University, Edirne, Turkey
| | - Muhammet Bektaş
- Istanbul Faculty of Medicine, Department of Biophysics, Istanbul University, Istanbul, Turkey
| | - Mine Yurtsever
- Department of Chemistry, Istanbul Technical University, Istanbul, Turkey
| | | | - Serdar Durdagi
- Department of Biophysics, School of Medicine, Bahcesehir University, Istanbul, Turkey
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13
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Özgeriş B, Göksu S, Polat Köse L, Gülçin İ, Salmas RE, Durdagi S, Tümer F, Supuran CT. Acetylcholinesterase and carbonic anhydrase inhibitory properties of novel urea and sulfamide derivatives incorporating dopaminergic 2-aminotetralin scaffolds. Bioorg Med Chem 2016; 24:2318-29. [DOI: 10.1016/j.bmc.2016.04.002] [Citation(s) in RCA: 105] [Impact Index Per Article: 13.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/21/2016] [Revised: 03/30/2016] [Accepted: 04/01/2016] [Indexed: 12/20/2022]
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Salmas RE, Yurtsever M, Durdagi S. Atomistic molecular dynamics simulations of typical and atypical antipsychotic drugs at the dopamine D2 receptor (D2R) elucidates their inhibition mechanism. J Biomol Struct Dyn 2016; 35:738-754. [DOI: 10.1080/07391102.2016.1159986] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/21/2022]
Affiliation(s)
| | - Mine Yurtsever
- Department of Chemistry, Istanbul Technical University, Istanbul, Turkey
| | - Serdar Durdagi
- Department of Biophysics, School of Medicine, Bahcesehir University, Istanbul, Turkey
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15
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Mirza SB, Salmas RE, Fatmi MQ, Durdagi S. Virtual screening of eighteen million compounds against dengue virus: Combined molecular docking and molecular dynamics simulations study. J Mol Graph Model 2016; 66:99-107. [PMID: 27054972 DOI: 10.1016/j.jmgm.2016.03.008] [Citation(s) in RCA: 30] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/18/2015] [Revised: 02/08/2016] [Accepted: 03/24/2016] [Indexed: 01/01/2023]
Abstract
Dengue virus is a major issue of tropical and sub-tropical regions. Dengue virus has been the cause behind the major alarming epidemics in the history with mass causalities from the decades. Unavailability of on-shelf drugs for the prevention of further proliferation of virus inside the human body results in immense number of deaths each year. This issue necessitates the design of novel anti-dengue drug. The protease enzyme pathway is the critical target for drug design due to its significance in the replication, survival and other cellular activities of dengue virus. Therefore, approximately eighteen million compounds from the ZINC database have been virtually screened against nonstructural protein 3 (NS3). The incremental construction algorithm of Glide docking program has been used with its features high throughput virtual screening (HTVS), standard precision (SP), extra precision (XP) and in combination of Prime module, induced fit docking (IFD) approach has also been applied. Five top-ranked compounds were then selected from the IFD results with better predicted binding energies with the catalytic triad residues (His51, Asp75, and Ser135) that may act as potential inhibitors for the underlying target protease enzyme. The top-ranked compounds ZINC95518765, ZINC44921800, ZINC71917414, ZINC39500661, ZINC36681949 have shown the predicted binding energies of -7.55, -7.36, -8.04, -8.41, -9.18kcal/mol, respectively, forming binding interactions with three catalytically important amino acids. Top-docking poses of compounds are then used in molecular dynamics (MD) simulations. In computational studies, our proposed compounds confirm promising results against all the four serotypes of dengue virus, strengthening the opportunity of these compounds to work as potential on-shelf drugs against dengue virus. Further experimentation on the proposed compounds can result in development of strong inhibitors.
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Affiliation(s)
- Shaher Bano Mirza
- Department of Biophysics, School of Medicine, Bahcesehir University (BAU), Istanbul, Turkey; Department of Biosciences, COMSATS Institute of Information Technology (CIIT), Park Road, Chak Shahzad, Islamabad, Pakistan
| | - Ramin Ekhteiari Salmas
- Department of Biophysics, School of Medicine, Bahcesehir University (BAU), Istanbul, Turkey
| | - M Qaiser Fatmi
- Department of Biosciences, COMSATS Institute of Information Technology (CIIT), Park Road, Chak Shahzad, Islamabad, Pakistan.
| | - Serdar Durdagi
- Department of Biophysics, School of Medicine, Bahcesehir University (BAU), Istanbul, Turkey.
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16
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Kaserer T, Lantero A, Schmidhammer H, Spetea M, Schuster D. μ Opioid receptor: novel antagonists and structural modeling. Sci Rep 2016; 6:21548. [PMID: 26888328 PMCID: PMC4757823 DOI: 10.1038/srep21548] [Citation(s) in RCA: 55] [Impact Index Per Article: 6.9] [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: 11/13/2015] [Accepted: 01/27/2016] [Indexed: 11/08/2022] Open
Abstract
The μ opioid receptor (MOR) is a prominent member of the G protein-coupled receptor family and the molecular target of morphine and other opioid drugs. Despite the long tradition of MOR-targeting drugs, still little is known about the ligand-receptor interactions and structure-function relationships underlying the distinct biological effects upon receptor activation or inhibition. With the resolved crystal structure of the β-funaltrexamine-MOR complex, we aimed at the discovery of novel agonists and antagonists using virtual screening tools, i.e. docking, pharmacophore- and shape-based modeling. We suggest important molecular interactions, which active molecules share and distinguish agonists and antagonists. These results allowed for the generation of theoretically validated in silico workflows that were employed for prospective virtual screening. Out of 18 virtual hits evaluated in in vitro pharmacological assays, three displayed antagonist activity and the most active compound significantly inhibited morphine-induced antinociception. The new identified chemotypes hold promise for further development into neurochemical tools for studying the MOR or as potential therapeutic lead candidates.
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Affiliation(s)
- Teresa Kaserer
- Computer-Aided Molecular Design Group, Department of Pharmaceutical Chemistry, Institute of Pharmacy and Center for Molecular Biosciences Innsbruck (CMBI), University of Innsbruck, Innrain 80-82, 6020 Innsbruck, Austria
| | - Aquilino Lantero
- Opioid Research Group, Department of Pharmaceutical Chemistry, Institute of Pharmacy and Center for Molecular Biosciences Innsbruck (CMBI), University of Innsbruck, Innrain 80-82, 6020 Innsbruck, Austria
| | - Helmut Schmidhammer
- Opioid Research Group, Department of Pharmaceutical Chemistry, Institute of Pharmacy and Center for Molecular Biosciences Innsbruck (CMBI), University of Innsbruck, Innrain 80-82, 6020 Innsbruck, Austria
| | - Mariana Spetea
- Opioid Research Group, Department of Pharmaceutical Chemistry, Institute of Pharmacy and Center for Molecular Biosciences Innsbruck (CMBI), University of Innsbruck, Innrain 80-82, 6020 Innsbruck, Austria
| | - Daniela Schuster
- Computer-Aided Molecular Design Group, Department of Pharmaceutical Chemistry, Institute of Pharmacy and Center for Molecular Biosciences Innsbruck (CMBI), University of Innsbruck, Innrain 80-82, 6020 Innsbruck, Austria
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17
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Durdagi S, Salmas RE, Stein M, Yurtsever M, Seeman P. Binding Interactions of Dopamine and Apomorphine in D2High and D2Low States of Human Dopamine D2 Receptor Using Computational and Experimental Techniques. ACS Chem Neurosci 2016; 7:185-95. [PMID: 26645629 DOI: 10.1021/acschemneuro.5b00271] [Citation(s) in RCA: 35] [Impact Index Per Article: 4.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/18/2023] Open
Abstract
We have recently reported G-protein coupled receptor (GPCR) model structures for the active and inactive states of the human dopamine D2 receptor (D2R) using adrenergic crystal structures as templates. Since the therapeutic concentrations of dopamine agonists that suppress the release of prolactin are the same as those that act at the high-affinity state of the D2 receptor (D2High), D2High in the anterior pituitary gland is considered to be the functional state of the receptor. In addition, the therapeutic concentrations of anti-Parkinson drugs are also related to the dissociation constants in the D2High form of the receptor. The discrimination between the high- and low-affinity (D2Low) components of the D2R is not obvious and requires advanced computer-assisted structural biology investigations. Therefore, in this work, the derived D2High and D2Low receptor models (GPCR monomer and dimer three-dimensional structures) are used as drug-binding targets to investigate binding interactions of dopamine and apomorphine. The study reveals a match between the experimental dissociation constants of dopamine and apomorphine at their high- and low-affinity sites of the D2 receptor in monomer and dimer and their calculated dissociation constants. The allosteric receptor-receptor interaction for dopamine D2R dimer is associated with the accessibility of adjacent residues of transmembrane region 4. The measured negative cooperativity between agonist ligand at dopamine D2 receptor is also correctly predicted using the D2R homodimerization model.
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Affiliation(s)
- Serdar Durdagi
- Department
of Biophysics, School of Medicine, Bahcesehir University, 34349 Istanbul, Turkey
| | - Ramin Ekhteiari Salmas
- Department
of Biophysics, School of Medicine, Bahcesehir University, 34349 Istanbul, Turkey
- Department
of Chemistry, Istanbul Technical University, 34469 Istanbul, Turkey
| | - Matthias Stein
- Molecular
Simulations and Design Group, Max-Planck Institute for Dynamics of Complex Technical Systems, Sandtorstrasse 1, 39106, Magdeburg, Germany
| | - Mine Yurtsever
- Department
of Chemistry, Istanbul Technical University, 34469 Istanbul, Turkey
| | - Philip Seeman
- Departments
of Pharmacology and Psychiatry, University of Toronto, 260 Heath
Street West, Unit 605, M5P 3L6, Toronto, Ontario Canada
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18
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Salmas RE, Mestanoglu M, Unlu A, Yurtsever M, Durdagi S. Mutated form (G52E) of inactive diphtheria toxin CRM197: molecular simulations clearly display effect of the mutation to NAD binding. J Biomol Struct Dyn 2016; 34:2462-8. [PMID: 26836774 DOI: 10.1080/07391102.2015.1119060] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/13/2023]
Abstract
Mutated form (G52E) of diphtheria toxin (DT) CRM197 is an inactive and nontoxic enzyme. Here, we provided a molecular insight using comparative molecular dynamics (MD) simulations to clarify the influence of a single point mutation on overall protein and active-site loop. Post-processing MD analysis (i.e. stability, principal component analysis, hydrogen-bond occupancy, etc.) is carried out on both wild and mutated targets to investigate and to better understand the mechanistic differences of structural and dynamical properties on an atomic scale especially at nicotinamide adenine dinucleotide (NAD) binding site when a single mutation (G52E) happens at the DT. In addition, a docking simulation is performed for wild and mutated forms. The docking scoring analysis and docking poses results revealed that mutant form is not able to properly accommodate the NAD molecule.
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Affiliation(s)
- Ramin Ekhteiari Salmas
- a Department of Chemistry , Istanbul Technical University , Istanbul , Turkey.,b Department of Biophysics , School of Medicine, Bahcesehir University , Istanbul , Turkey
| | - Mert Mestanoglu
- c School of Medicine , Bahcesehir University , Istanbul , Turkey
| | - Ayhan Unlu
- d Faculty of Medicine, Department of Biophysics , Trakya University , Edirne , Turkey
| | - Mine Yurtsever
- a Department of Chemistry , Istanbul Technical University , Istanbul , Turkey
| | - Serdar Durdagi
- b Department of Biophysics , School of Medicine, Bahcesehir University , Istanbul , Turkey
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19
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Abstract
Aspalathin and nothofagin are the major dihydrochalcones found in rooibos (Aspalathus linearis), which display anti-diabetic activities, but the mechanism is still unclear. In this paper, hSGLT2 (human sodium dependent glucose co-transporter 2), a target for diabetes mellitus, was built using homology modeling method. Molecular docking and dynamics simulations were carried out on aspalathin, nothofagin and SGLT2 complexes with dapagliflozin as positive control. The results show that both the binding energies and binding modes of aspalathin and nothofagin are similar to dapagliflozin, indicating that either component of rooibos may exhibit anti-diabetic effects through inhibiting SGLT2 receptor. However, the predicted permeability value of aspalathin and nothofagin is low, which may cause poor absorption, resulting in weak SGLT2 inhibition. Calculation results elucidate the possible inhibiting mechanism of aspalathin and nothofagin against SGLT2, and therefore enhance our understanding of anti-diabetic activities of rooibos.
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Affiliation(s)
- Wei Liu
- Tianjin Key Laboratory of Molecular Design and Drug Discovery, Tianjin Institute of Pharmaceutical Research, Tianjin 300193, P. R. China
| | - Huanjie Wang
- State Key Laboratory of Drug Delivery Technology and Pharmacokinetics, Tianjin Institute of Pharmaceutical Research, Tianjin 300193, P. R. China
| | - Fancui Meng
- Tianjin Key Laboratory of Molecular Design and Drug Discovery, Tianjin Institute of Pharmaceutical Research, Tianjin 300193, P. R. China
- State Key Laboratory of Drug Delivery Technology and Pharmacokinetics, Tianjin Institute of Pharmaceutical Research, Tianjin 300193, P. R. China
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20
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Abstract
This paper is the thirty-seventh consecutive installment of the annual review of research concerning the endogenous opioid system. It summarizes papers published during 2014 that studied the behavioral effects of molecular, pharmacological and genetic manipulation of opioid peptides, opioid receptors, opioid agonists and opioid antagonists. The particular topics that continue to be covered include the molecular-biochemical effects and neurochemical localization studies of endogenous opioids and their receptors related to behavior (endogenous opioids and receptors), and the roles of these opioid peptides and receptors in pain and analgesia (pain and analgesia); stress and social status (human studies); tolerance and dependence (opioid mediation of other analgesic responses); learning and memory (stress and social status); eating and drinking (stress-induced analgesia); alcohol and drugs of abuse (emotional responses in opioid-mediated behaviors); sexual activity and hormones, pregnancy, development and endocrinology (opioid involvement in stress response regulation); mental illness and mood (tolerance and dependence); seizures and neurologic disorders (learning and memory); electrical-related activity and neurophysiology (opiates and conditioned place preferences (CPP)); general activity and locomotion (eating and drinking); gastrointestinal, renal and hepatic functions (alcohol and drugs of abuse); cardiovascular responses (opiates and ethanol); respiration and thermoregulation (opiates and THC); and immunological responses (opiates and stimulants). This paper is the thirty-seventh consecutive installment of the annual review of research concerning the endogenous opioid system. It summarizes papers published during 2014 that studied the behavioral effects of molecular, pharmacological and genetic manipulation of opioid peptides, opioid receptors, opioid agonists and opioid antagonists. The particular topics that continue to be covered include the molecular-biochemical effects and neurochemical localization studies of endogenous opioids and their receptors related to behavior (endogenous opioids and receptors), and the roles of these opioid peptides and receptors in pain and analgesia (pain and analgesia); stress and social status (human studies); tolerance and dependence (opioid mediation of other analgesic responses); learning and memory (stress and social status); eating and drinking (stress-induced analgesia); alcohol and drugs of abuse (emotional responses in opioid-mediated behaviors); sexual activity and hormones, pregnancy, development and endocrinology (opioid involvement in stress response regulation); mental illness and mood (tolerance and dependence); seizures and neurologic disorders (learning and memory); electrical-related activity and neurophysiology (opiates and conditioned place preferences (CPP)); general activity and locomotion (eating and drinking); gastrointestinal, renal and hepatic functions (alcohol and drugs of abuse); cardiovascular responses (opiates and ethanol); respiration and thermoregulation (opiates and THC); and immunological responses (opiates and stimulants).
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Affiliation(s)
- Richard J Bodnar
- Department of Psychology and Neuropsychology Doctoral Sub-Program, Queens College, City University of New York, Flushing, NY 11367, United States.
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21
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Leonis G, Avramopoulos A, Papavasileiou KD, Reis H, Steinbrecher T, Papadopoulos MG. A Comprehensive Computational Study of the Interaction between Human Serum Albumin and Fullerenes. J Phys Chem B 2015; 119:14971-85. [PMID: 26523956 DOI: 10.1021/acs.jpcb.5b05998] [Citation(s) in RCA: 18] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/01/2023]
Abstract
Human serum albumin (HSA) is the most abundant blood plasma protein, which transports fatty acids, hormones, and drugs. We consider nanoparticle-HSA interactions by investigating the binding of HSA with three fullerene analogs. Long MD simulations, quantum mechanical (fragment molecular orbital, energy decomposition analysis, atoms-in-molecules), and free energy methods elucidated the binding mechanism in these complexes. Such a systematic study is valuable due to the lack of comprehensive theoretical approaches to date. The main elements of the mechanism include the following: binding to IIA site results in allosteric modulation of the IIIA and heme binding sites with an increase in α-helical structure of IIIA. Fullerenes displayed high binding affinities for HSA; therefore, HSA can be used as a fullerene carrier, facilitating any toxic function the fullerene may exert. Complex formation is driven by hydrogen bonding, van der Waals, nonpolar, charge transfer, and dispersion energy contributions. Proper functionalization of C60 has enhanced its binding to HSA by more than an order of magnitude. This feature may be important for biological applications (e.g., photodynamic therapy of cancer). Satisfactory agreement with relevant experimental and theoretical data has been obtained.
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Affiliation(s)
- Georgios Leonis
- Institute of Biology, Pharmaceutical Chemistry and Biotechnology, National Hellenic Research Foundation , 48 Vas. Constantinou Ave., Athens 11635, Greece
| | - Aggelos Avramopoulos
- Institute of Biology, Pharmaceutical Chemistry and Biotechnology, National Hellenic Research Foundation , 48 Vas. Constantinou Ave., Athens 11635, Greece
| | - Konstantinos D Papavasileiou
- Institute of Biology, Pharmaceutical Chemistry and Biotechnology, National Hellenic Research Foundation , 48 Vas. Constantinou Ave., Athens 11635, Greece
| | - Heribert Reis
- Institute of Biology, Pharmaceutical Chemistry and Biotechnology, National Hellenic Research Foundation , 48 Vas. Constantinou Ave., Athens 11635, Greece
| | - Thomas Steinbrecher
- Institut für Physikalische Chemie, KIT , Fritz-Haber Weg 2, 76131 Karlsruhe, Germany
| | - Manthos G Papadopoulos
- Institute of Biology, Pharmaceutical Chemistry and Biotechnology, National Hellenic Research Foundation , 48 Vas. Constantinou Ave., Athens 11635, Greece
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22
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Shang Y, Filizola M. Opioid receptors: Structural and mechanistic insights into pharmacology and signaling. Eur J Pharmacol 2015; 763:206-13. [PMID: 25981301 DOI: 10.1016/j.ejphar.2015.05.012] [Citation(s) in RCA: 59] [Impact Index Per Article: 6.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/25/2015] [Revised: 03/02/2015] [Accepted: 05/11/2015] [Indexed: 01/18/2023]
Abstract
Opioid receptors are important drug targets for pain management, addiction, and mood disorders. Although substantial research on these important subtypes of G protein-coupled receptors has been conducted over the past two decades to discover ligands with higher specificity and diminished side effects, currently used opioid therapeutics remain suboptimal. Luckily, recent advances in structural biology of opioid receptors provide unprecedented insights into opioid receptor pharmacology and signaling. We review here a few recent studies that have used the crystal structures of opioid receptors as a basis for revealing mechanistic details of signal transduction mediated by these receptors, and for the purpose of drug discovery.
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Affiliation(s)
- Yi Shang
- Icahn School of Medicine at Mount Sinai, Department of Structural and Chemical Biology, One Gustave, L. Levy Place, Box 1677, New York, NY 10029, USA
| | - Marta Filizola
- Icahn School of Medicine at Mount Sinai, Department of Structural and Chemical Biology, One Gustave, L. Levy Place, Box 1677, New York, NY 10029, USA.
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23
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Guerrieri E, Mallareddy JR, Tóth G, Schmidhammer H, Spetea M. Synthesis and pharmacological evaluation of [(3)H]HS665, a novel, highly selective radioligand for the kappa opioid receptor. ACS Chem Neurosci 2015; 6:456-63. [PMID: 25496417 DOI: 10.1021/cn5002792] [Citation(s) in RCA: 17] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/19/2022] Open
Abstract
Herein we report the radiolabeling and pharmacological investigation of a novel radioligand, the N-cyclobutylmethyl substituted diphenethylamine [(3)H]HS665, designed to bind selectively to the kappa opioid peptide (KOP) receptor, a target of therapeutic interest for the treatment of a variety of human disorders (i.e., pain, affective disorders, drug addiction, and psychotic disorders). HS665 was prepared in tritium-labeled form by a dehalotritiated method resulting in a specific activity of 30.65 Ci/mmol. Radioligand binding studies were performed to establish binding properties of [(3)H]HS665 to the recombinant human KOP receptor in membranes from Chinese hamster ovary cells stably expressing human KOP receptors (CHOhKOP) and to the native neuronal KOP receptor in guinea pig brain membranes. Binding of [(3)H]HS665 was specific and saturable in both tissue preparations. A single population of high affinity binding sites was labeled by [(3)H]HS665 in membranes from CHOhKOP cells and guinea pig brain with similar equilibrium dissociation constants, Kd, 0.45 and 0.64 nM, respectively. Average receptor density of [(3)H]HS665 recognition sites were 5564 and 154 fmol/mg protein in CHOhKOP cells and guinea pig brain, respectively. This study shows that the new radioligand distinguishes and labels KOP receptors specifically in neuronal and cellular systems expressing KOP receptors, making this molecule a valuable tool in probing structural and functional mechanisms governing ligand-KOP receptor interactions in both a recombinant and native in vitro setting.
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Affiliation(s)
- Elena Guerrieri
- Department of Pharmaceutical Chemistry, Institute of Pharmacy and Center for Molecular Biosciences (CMBI), University of Innsbruck, Innrain 80-82, A-6020 Innsbruck, Austria
| | - Jayapal Reddy Mallareddy
- Institute of Biochemistry, Biological Research Centre, Hungarian Academy of Sciences, Temesvari krt 62, H-6726 Szeged, Hungary
| | - Géza Tóth
- Institute of Biochemistry, Biological Research Centre, Hungarian Academy of Sciences, Temesvari krt 62, H-6726 Szeged, Hungary
| | - Helmut Schmidhammer
- Department of Pharmaceutical Chemistry, Institute of Pharmacy and Center for Molecular Biosciences (CMBI), University of Innsbruck, Innrain 80-82, A-6020 Innsbruck, Austria
| | - Mariana Spetea
- Department of Pharmaceutical Chemistry, Institute of Pharmacy and Center for Molecular Biosciences (CMBI), University of Innsbruck, Innrain 80-82, A-6020 Innsbruck, Austria
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