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Tucci P, Brown I, Bewick GS, Pertwee RG, Marini P. The Plant Derived 3-3'-Diindolylmethane (DIM) Behaves as CB 2 Receptor Agonist in Prostate Cancer Cellular Models. Int J Mol Sci 2023; 24:ijms24043620. [PMID: 36835033 PMCID: PMC9962283 DOI: 10.3390/ijms24043620] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/28/2022] [Revised: 01/30/2023] [Accepted: 02/09/2023] [Indexed: 02/15/2023] Open
Abstract
3-3'-Diindolylmethane (DIM) is a biologically active dimer derived from the endogenous conversion of indole-3-carbinol (I3C), a naturally occurring glucosinolate found in many cruciferous vegetables (i.e., Brassicaceae). DIM was the first pure androgen receptor antagonist isolated from the Brassicaceae family and has been recently investigated for its potential pharmacological use in prostate cancer prevention and treatment. Interestingly, there is evidence that DIM can also interact with cannabinoid receptors. In this context, by considering the well-known involvement of the endocannabinoid system in prostate cancer, we have pharmacologically characterized the properties of DIM on both CB1 and CB2 cannabinoid receptors in two human prostate cancer cell lines: PC3 (androgen-independent/androgen receptor negative) and LNCaP (androgen-dependent). In the PC3 cell line, DIM was able to activate CB2 receptors and potentially associated apoptotic pathways. On the other hand, although DIM was also able to activate CB2 receptors in the LNCaP cell line, no apoptotic effects were observed. Our evidence confirms that DIM is a CB2 receptor ligand and, moreover, it has a potential anti-proliferative effect on androgen-independent/androgen receptor-negative prostate cancer cells.
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Affiliation(s)
- Paolo Tucci
- Department of Clinical and Experimental Medicine, University of Foggia, 71122 Foggia, Italy
- Correspondence:
| | - Iain Brown
- Division of Applied Medicine, School of Medicine and Dentistry, Foresterhill, University of Aberdeen, Aberdeen AB25 2ZD, UK
| | - Guy S. Bewick
- The Institute of Medical Sciences, Foresterhill, University of Aberdeen, Aberdeen AB25 2ZD, UK
| | - Roger G. Pertwee
- The Institute of Medical Sciences, Foresterhill, University of Aberdeen, Aberdeen AB25 2ZD, UK
| | - Pietro Marini
- Institute of Education in Healthcare and Medical Sciences, Foresterhill, University of Aberdeen, Aberdeen AB25 2ZD, UK
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2
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Yuan J, Jiang C, Wang J, Chen CJ, Hao Y, Zhao G, Feng Z, Xie XQ. In Silico Prediction and Validation of CB2 Allosteric Binding Sites to Aid the Design of Allosteric Modulators. Molecules 2022; 27:molecules27020453. [PMID: 35056767 PMCID: PMC8781014 DOI: 10.3390/molecules27020453] [Citation(s) in RCA: 4] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/10/2021] [Revised: 01/01/2022] [Accepted: 01/03/2022] [Indexed: 11/16/2022] Open
Abstract
Although the 3D structures of active and inactive cannabinoid receptors type 2 (CB2) are available, neither the X-ray crystal nor the cryo-EM structure of CB2-orthosteric ligand-modulator has been resolved, prohibiting the drug discovery and development of CB2 allosteric modulators (AMs). In the present work, we mainly focused on investigating the potential allosteric binding site(s) of CB2. We applied different algorithms or tools to predict the potential allosteric binding sites of CB2 with the existing agonists. Seven potential allosteric sites can be observed for either CB2-CP55940 or CB2-WIN 55,212-2 complex, among which sites B, C, G and K are supported by the reported 3D structures of Class A GPCRs coupled with AMs. Applying our novel algorithm toolset-MCCS, we docked three known AMs of CB2 including Ec2la (C-2), trans-β-caryophyllene (TBC) and cannabidiol (CBD) to each site for further comparisons and quantified the potential binding residues in each allosteric binding site. Sequentially, we selected the most promising binding pose of C-2 in five allosteric sites to conduct the molecular dynamics (MD) simulations. Based on the results of docking studies and MD simulations, we suggest that site H is the most promising allosteric binding site. We plan to conduct bio-assay validations in the future.
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Affiliation(s)
- Jiayi Yuan
- Department of Pharmaceutical Sciences and Computational Chemical Genomics Screening Center, School of Pharmacy, University of Pittsburgh, Pittsburgh, PA 15261, USA; (J.Y.); (C.J.); (J.W.); (C.-J.C.); (Y.H.); (G.Z.)
- Department of Pharmaceutical Sciences and National Center of Excellence for Computational Drug Abuse Research, School of Pharmacy, University of Pittsburgh, Pittsburgh, PA 15261, USA
| | - Chen Jiang
- Department of Pharmaceutical Sciences and Computational Chemical Genomics Screening Center, School of Pharmacy, University of Pittsburgh, Pittsburgh, PA 15261, USA; (J.Y.); (C.J.); (J.W.); (C.-J.C.); (Y.H.); (G.Z.)
- Department of Pharmaceutical Sciences and National Center of Excellence for Computational Drug Abuse Research, School of Pharmacy, University of Pittsburgh, Pittsburgh, PA 15261, USA
| | - Junmei Wang
- Department of Pharmaceutical Sciences and Computational Chemical Genomics Screening Center, School of Pharmacy, University of Pittsburgh, Pittsburgh, PA 15261, USA; (J.Y.); (C.J.); (J.W.); (C.-J.C.); (Y.H.); (G.Z.)
- Department of Pharmaceutical Sciences and National Center of Excellence for Computational Drug Abuse Research, School of Pharmacy, University of Pittsburgh, Pittsburgh, PA 15261, USA
| | - Chih-Jung Chen
- Department of Pharmaceutical Sciences and Computational Chemical Genomics Screening Center, School of Pharmacy, University of Pittsburgh, Pittsburgh, PA 15261, USA; (J.Y.); (C.J.); (J.W.); (C.-J.C.); (Y.H.); (G.Z.)
- Department of Pharmaceutical Sciences and National Center of Excellence for Computational Drug Abuse Research, School of Pharmacy, University of Pittsburgh, Pittsburgh, PA 15261, USA
| | - Yixuan Hao
- Department of Pharmaceutical Sciences and Computational Chemical Genomics Screening Center, School of Pharmacy, University of Pittsburgh, Pittsburgh, PA 15261, USA; (J.Y.); (C.J.); (J.W.); (C.-J.C.); (Y.H.); (G.Z.)
- Department of Pharmaceutical Sciences and National Center of Excellence for Computational Drug Abuse Research, School of Pharmacy, University of Pittsburgh, Pittsburgh, PA 15261, USA
| | - Guangyi Zhao
- Department of Pharmaceutical Sciences and Computational Chemical Genomics Screening Center, School of Pharmacy, University of Pittsburgh, Pittsburgh, PA 15261, USA; (J.Y.); (C.J.); (J.W.); (C.-J.C.); (Y.H.); (G.Z.)
- Department of Pharmaceutical Sciences and National Center of Excellence for Computational Drug Abuse Research, School of Pharmacy, University of Pittsburgh, Pittsburgh, PA 15261, USA
| | - Zhiwei Feng
- Department of Pharmaceutical Sciences and Computational Chemical Genomics Screening Center, School of Pharmacy, University of Pittsburgh, Pittsburgh, PA 15261, USA; (J.Y.); (C.J.); (J.W.); (C.-J.C.); (Y.H.); (G.Z.)
- Department of Pharmaceutical Sciences and National Center of Excellence for Computational Drug Abuse Research, School of Pharmacy, University of Pittsburgh, Pittsburgh, PA 15261, USA
- Correspondence: (Z.F.); (X.-Q.X.)
| | - Xiang-Qun Xie
- Department of Pharmaceutical Sciences and Computational Chemical Genomics Screening Center, School of Pharmacy, University of Pittsburgh, Pittsburgh, PA 15261, USA; (J.Y.); (C.J.); (J.W.); (C.-J.C.); (Y.H.); (G.Z.)
- Department of Pharmaceutical Sciences and National Center of Excellence for Computational Drug Abuse Research, School of Pharmacy, University of Pittsburgh, Pittsburgh, PA 15261, USA
- Correspondence: (Z.F.); (X.-Q.X.)
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Wang M, Hou S, Liu Y, Li D, Lin J. Identification of Novel Antagonists Targeting Cannabinoid Receptor 2 Using a Multi-Step Virtual Screening Strategy. Molecules 2021; 26:molecules26216679. [PMID: 34771087 PMCID: PMC8587544 DOI: 10.3390/molecules26216679] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/23/2021] [Revised: 10/30/2021] [Accepted: 11/02/2021] [Indexed: 11/28/2022] Open
Abstract
The endocannabinoid system plays an essential role in the regulation of analgesia and human immunity, and Cannabinoid Receptor 2 (CB2) has been proved to be an ideal target for the treatment of liver diseases and some cancers. In this study, we identified CB2 antagonists using a three-step “deep learning–pharmacophore–molecular docking” virtual screening approach. From the ChemDiv database (1,178,506 compounds), 15 hits were selected and tested by radioligand binding assays and cAMP functional assays. A total of 7 out of the 15 hits were found to exhibit binding affinities in the radioligand binding assays against CB2 receptor, with a pKi of 5.15–6.66, among which five compounds showed antagonistic activities with pIC50 of 5.25–6.93 in the cAMP functional assays. Among these hits, Compound 8 with the 4H-pyrido[1,2-a]pyrimidin-4-one scaffold showed the best binding affinity and antagonistic activity with a pKi of 6.66 and pIC50 of 6.93, respectively. The new scaffold could serve as a lead for further development of CB2 drugs. Additionally, we hope that the model in this study could be further utilized to identify more novel CB2 receptor antagonists, and the developed approach could also be used to design potent ligands for other therapeutic targets.
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Affiliation(s)
- Mukuo Wang
- State Key Laboratory of Medicinal Chemical Biology, College of Pharmacy, Tianjin Key Laboratory of Molecular Drug Research, Nankai University, Haihe Education Park, 38 Tongyan Road, Tianjin 300350, China; (M.W.); (S.H.); (Y.L.)
| | - Shujing Hou
- State Key Laboratory of Medicinal Chemical Biology, College of Pharmacy, Tianjin Key Laboratory of Molecular Drug Research, Nankai University, Haihe Education Park, 38 Tongyan Road, Tianjin 300350, China; (M.W.); (S.H.); (Y.L.)
| | - Ye Liu
- State Key Laboratory of Medicinal Chemical Biology, College of Pharmacy, Tianjin Key Laboratory of Molecular Drug Research, Nankai University, Haihe Education Park, 38 Tongyan Road, Tianjin 300350, China; (M.W.); (S.H.); (Y.L.)
| | - Dongmei Li
- State Key Laboratory of Medicinal Chemical Biology, College of Pharmacy, Tianjin Key Laboratory of Molecular Drug Research, Nankai University, Haihe Education Park, 38 Tongyan Road, Tianjin 300350, China; (M.W.); (S.H.); (Y.L.)
- Correspondence: (D.L.); (J.L.)
| | - Jianping Lin
- State Key Laboratory of Medicinal Chemical Biology, College of Pharmacy, Tianjin Key Laboratory of Molecular Drug Research, Nankai University, Haihe Education Park, 38 Tongyan Road, Tianjin 300350, China; (M.W.); (S.H.); (Y.L.)
- Biodesign Center, Tianjin Institute of Industrial Biotechnology, Chinese Academy of Sciences, 32 West 7th Avenue, Tianjin Airport Economic Area, Tianjin 300308, China
- Platform of Pharmaceutical Intelligence, Tianjin International Joint Academy of Biomedicine, Tianjin 300457, China
- Correspondence: (D.L.); (J.L.)
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Faúndez-Parraguez M, Alarcón-Miranda C, Cho YH, Pessoa-Mahana H, Gallardo-Garrido C, Chung H, Faúndez M, Pessoa-Mahana D. New Pyridone-Based Derivatives as Cannabinoid Receptor Type 2 Agonists. Int J Mol Sci 2021; 22:11212. [PMID: 34681877 PMCID: PMC8537746 DOI: 10.3390/ijms222011212] [Citation(s) in RCA: 6] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/07/2021] [Revised: 09/28/2021] [Accepted: 10/08/2021] [Indexed: 12/12/2022] Open
Abstract
The activation of the human cannabinoid receptor type II (CB2R) is known to mediate analgesic and anti-inflammatory processes without the central adverse effects related to cannabinoid receptor type I (CB1R). In this work we describe the synthesis and evaluation of a novel series of N-aryl-2-pyridone-3-carboxamide derivatives tested as human cannabinoid receptor type II (CB2R) agonists. Different cycloalkanes linked to the N-aryl pyridone by an amide group displayed CB2R agonist activity as determined by intracellular [cAMP] levels. The most promising compound 8d exhibited a non-toxic profile and similar potency (EC50 = 112 nM) to endogenous agonists Anandamide (AEA) and 2-Arachidonoylglycerol (2-AG) providing new information for the development of small molecules activating CB2R. Molecular docking studies showed a binding pose consistent with two structurally different agonists WIN-55212-2 and AM12033 and suggested structural requirements on the pyridone substituents that can satisfy the orthosteric pocket and induce an agonist response. Our results provide additional evidence to support the 2-pyridone ring as a suitable scaffold for the design of CB2R agonists and represent a starting point for further optimization and development of novel compounds for the treatment of pain and inflammation.
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Affiliation(s)
- Manuel Faúndez-Parraguez
- Pharmacy Department, Faculty of Chemistry, Pontificia Universidad Católica de Chile, Vicuña Mackenna 4860, Santiago 7820436, Chile; (C.A.-M.); (Y.H.C.); (C.G.-G.); (H.C.); (M.F.)
| | - Carlos Alarcón-Miranda
- Pharmacy Department, Faculty of Chemistry, Pontificia Universidad Católica de Chile, Vicuña Mackenna 4860, Santiago 7820436, Chile; (C.A.-M.); (Y.H.C.); (C.G.-G.); (H.C.); (M.F.)
| | - Young Hwa Cho
- Pharmacy Department, Faculty of Chemistry, Pontificia Universidad Católica de Chile, Vicuña Mackenna 4860, Santiago 7820436, Chile; (C.A.-M.); (Y.H.C.); (C.G.-G.); (H.C.); (M.F.)
| | - Hernán Pessoa-Mahana
- Organic Chemistry and Physical Chemistry Department, Faculty of Chemical and Pharmaceutical Sciences, Universidad de Chile, Olivos 1007, Santiago 7820436, Chile;
| | - Carlos Gallardo-Garrido
- Pharmacy Department, Faculty of Chemistry, Pontificia Universidad Católica de Chile, Vicuña Mackenna 4860, Santiago 7820436, Chile; (C.A.-M.); (Y.H.C.); (C.G.-G.); (H.C.); (M.F.)
| | - Hery Chung
- Pharmacy Department, Faculty of Chemistry, Pontificia Universidad Católica de Chile, Vicuña Mackenna 4860, Santiago 7820436, Chile; (C.A.-M.); (Y.H.C.); (C.G.-G.); (H.C.); (M.F.)
| | - Mario Faúndez
- Pharmacy Department, Faculty of Chemistry, Pontificia Universidad Católica de Chile, Vicuña Mackenna 4860, Santiago 7820436, Chile; (C.A.-M.); (Y.H.C.); (C.G.-G.); (H.C.); (M.F.)
| | - David Pessoa-Mahana
- Pharmacy Department, Faculty of Chemistry, Pontificia Universidad Católica de Chile, Vicuña Mackenna 4860, Santiago 7820436, Chile; (C.A.-M.); (Y.H.C.); (C.G.-G.); (H.C.); (M.F.)
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5
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Abstract
The Sterling Research Group identified pravadoline as an aminoalkylindole (AAI) non-steroidal anti-inflammatory pain reliever. As drug design progressed, the ability of AAI analogs to block prostaglandin synthesis diminished, and antinociceptive activity was found to result from action at the CB1 cannabinoid receptor, a G-protein-coupled receptor (GPCR) abundant in the brain. Several laboratories applied computational chemistry methods to ultimately conclude that AAI and cannabinoid ligands could overlap within a common binding pocket but that WIN55212-2 primarily utilized steric interactions via aromatic stacking, whereas cannabinoid ligands required some electrostatic interactions, particularly involving the CB1 helix-3 lysine. The Huffman laboratory identified strategies to establish CB2 receptor selectivity among cannabimimetic indoles to avoid their CB1-related adverse effects, thereby stimulating preclinical studies to explore their use as anti-hyperalgesic and anti-allodynic pharmacotherapies. Some AAI analogs activate novel GPCRs referred to as "Alkyl Indole" receptors, and some AAI analogs act at the colchicine-binding site on microtubules. The AAI compounds having the greatest potency to interact with the CB1 receptor have found their way into the market as "Spice" or "K2". The sale of these alleged "herbal products" evades FDA consumer protections for proper labeling and safety as a medicine, as well as DEA scheduling as compounds having no currently accepted medical use and a high potential for abuse. The distribution to the public of potent alkyl indole synthetic cannabimimetic chemicals without regard for consumer safety contrasts with the adherence to regulatory requirements for demonstration of safety that are routinely observed by ethical pharmaceutical companies that market medicines.
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Affiliation(s)
- Allyn C. Howlett
- Department of Physiology and Pharmacology, Wake Forest School of Medicine, Winston-Salem, NC 27157, USA
| | - Brian F. Thomas
- Department of Analytical Sciences, The Cronos Group, Toronto, ON M5V 2H1, Canada;
| | - John W. Huffman
- Department of Chemistry, Clemson University, Clemson, SC 29634, USA;
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6
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Teodoro R, Gündel D, Deuther-Conrad W, Ueberham L, Toussaint M, Bormans G, Brust P, Moldovan RP. Development of [ 18F]LU14 for PET Imaging of Cannabinoid Receptor Type 2 in the Brain. Int J Mol Sci 2021; 22:ijms22158051. [PMID: 34360817 PMCID: PMC8347709 DOI: 10.3390/ijms22158051] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/25/2021] [Revised: 07/20/2021] [Accepted: 07/23/2021] [Indexed: 12/16/2022] Open
Abstract
Cannabinoid receptors type 2 (CB2R) represent an attractive therapeutic target for neurodegenerative diseases and cancer. Aiming at the development of a positron emission tomography (PET) radiotracer to monitor receptor density and/or occupancy during a CB2R-tailored therapy, we herein describe the radiosynthesis of cis-[18F]1-(4-fluorobutyl-N-((1s,4s)-4-methylcyclohexyl)-2-oxo-1,2-dihydro-1,8-naphthyridine-3-carboxamide ([18F]LU14) starting from the corresponding mesylate precursor. The first biological evaluation revealed that [18F]LU14 is a highly affine CB2R radioligand with >80% intact tracer in the brain at 30 min p.i. Its further evaluation by PET in a well-established rat model of CB2R overexpression demonstrated its ability to selectively image the CB2R in the brain and its potential as a tracer to further investigate disease-related changes in CB2R expression.
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Affiliation(s)
- Rodrigo Teodoro
- Helmholtz-Zentrum Dresden-Rossendorf (HZDR), Institute of Radiopharmaceutical Cancer Research, Department of Neuroradiopharmaceuticals, Research Site Leipzig, 04318 Leipzig, Germany; (R.T.); (D.G.); (W.D.-C.); (L.U.); (M.T.); (P.B.)
| | - Daniel Gündel
- Helmholtz-Zentrum Dresden-Rossendorf (HZDR), Institute of Radiopharmaceutical Cancer Research, Department of Neuroradiopharmaceuticals, Research Site Leipzig, 04318 Leipzig, Germany; (R.T.); (D.G.); (W.D.-C.); (L.U.); (M.T.); (P.B.)
| | - Winnie Deuther-Conrad
- Helmholtz-Zentrum Dresden-Rossendorf (HZDR), Institute of Radiopharmaceutical Cancer Research, Department of Neuroradiopharmaceuticals, Research Site Leipzig, 04318 Leipzig, Germany; (R.T.); (D.G.); (W.D.-C.); (L.U.); (M.T.); (P.B.)
| | - Lea Ueberham
- Helmholtz-Zentrum Dresden-Rossendorf (HZDR), Institute of Radiopharmaceutical Cancer Research, Department of Neuroradiopharmaceuticals, Research Site Leipzig, 04318 Leipzig, Germany; (R.T.); (D.G.); (W.D.-C.); (L.U.); (M.T.); (P.B.)
| | - Magali Toussaint
- Helmholtz-Zentrum Dresden-Rossendorf (HZDR), Institute of Radiopharmaceutical Cancer Research, Department of Neuroradiopharmaceuticals, Research Site Leipzig, 04318 Leipzig, Germany; (R.T.); (D.G.); (W.D.-C.); (L.U.); (M.T.); (P.B.)
| | - Guy Bormans
- Radiopharmaceutical Research, Department of Pharmaceutical and Pharmacological Sciences, KU Leuven, BE-3000 Leuven, Belgium;
| | - Peter Brust
- Helmholtz-Zentrum Dresden-Rossendorf (HZDR), Institute of Radiopharmaceutical Cancer Research, Department of Neuroradiopharmaceuticals, Research Site Leipzig, 04318 Leipzig, Germany; (R.T.); (D.G.); (W.D.-C.); (L.U.); (M.T.); (P.B.)
- The Lübeck Institute of Experimental Dermatology, University Medical Center Schleswig-Holstein, 23562 Lübeck, Germany
| | - Rareş-Petru Moldovan
- Helmholtz-Zentrum Dresden-Rossendorf (HZDR), Institute of Radiopharmaceutical Cancer Research, Department of Neuroradiopharmaceuticals, Research Site Leipzig, 04318 Leipzig, Germany; (R.T.); (D.G.); (W.D.-C.); (L.U.); (M.T.); (P.B.)
- Correspondence: ; Tel.: +49-3412-3417-94634
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7
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Turu G, Soltész-Katona E, Tóth AD, Juhász C, Cserző M, Misák Á, Balla A, Caron MG, Hunyady L. Biased Coupling to β-Arrestin of Two Common Variants of the CB 2 Cannabinoid Receptor. Front Endocrinol (Lausanne) 2021; 12:714561. [PMID: 34484125 PMCID: PMC8415483 DOI: 10.3389/fendo.2021.714561] [Citation(s) in RCA: 8] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 05/25/2021] [Accepted: 07/08/2021] [Indexed: 01/14/2023] Open
Abstract
β-arrestins are partners of the G protein-coupled receptors (GPCRs), regulating their intracellular trafficking and signaling. Development of biased GPCR agonists, selectively targeting either G protein or β-arrestin pathways, are in the focus of interest due to their therapeutic potential in different pathological conditions. The CB2 cannabinoid receptor (CB2R) is a GPCR involved in various functions in the periphery and the central nervous system. Two common occurring variants of CB2R, harboring Q63R or L133I missense mutations, have been implicated in the development of a diverse set of disorders. To evaluate the effect of these mutations, we characterized the binding profile of these mutant CB2 receptors to G proteins and β-arrestin2. Although their ability to inhibit cAMP signaling was similar, the Q63R mutant had increased, whereas the L133I mutant receptor had decreased β-arrestin2 binding. In line with these observations, the variants also had altered intracellular trafficking. Our results show that two common variants of the CB2 receptor have biased signaling properties, which may contribute to the pathogenesis of the associated disorders and may offer CB2R as a target for further development of biased receptor activation strategies.
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Affiliation(s)
- Gábor Turu
- Department of Physiology, Faculty of Medicine, Semmelweis University, Budapest, Hungary
- MTA-SE Laboratory of Molecular Physiology, Hungarian Academy of Sciences and Semmelweis University, Budapest, Hungary
- Department of Cell Biology, Duke University Medical Center, Duke University School of Medicine, Durham, NC, United States
- *Correspondence: Gábor Turu, ; László Hunyady,
| | - Eszter Soltész-Katona
- Department of Physiology, Faculty of Medicine, Semmelweis University, Budapest, Hungary
- MTA-SE Laboratory of Molecular Physiology, Hungarian Academy of Sciences and Semmelweis University, Budapest, Hungary
| | - András Dávid Tóth
- Department of Physiology, Faculty of Medicine, Semmelweis University, Budapest, Hungary
- MTA-SE Laboratory of Molecular Physiology, Hungarian Academy of Sciences and Semmelweis University, Budapest, Hungary
| | - Cintia Juhász
- Department of Physiology, Faculty of Medicine, Semmelweis University, Budapest, Hungary
| | - Miklós Cserző
- Department of Physiology, Faculty of Medicine, Semmelweis University, Budapest, Hungary
- MTA-SE Laboratory of Molecular Physiology, Hungarian Academy of Sciences and Semmelweis University, Budapest, Hungary
| | - Ádám Misák
- Department of Physiology, Faculty of Medicine, Semmelweis University, Budapest, Hungary
| | - András Balla
- Department of Physiology, Faculty of Medicine, Semmelweis University, Budapest, Hungary
- MTA-SE Laboratory of Molecular Physiology, Hungarian Academy of Sciences and Semmelweis University, Budapest, Hungary
| | - Marc G. Caron
- Department of Cell Biology, Duke University Medical Center, Duke University School of Medicine, Durham, NC, United States
| | - László Hunyady
- Department of Physiology, Faculty of Medicine, Semmelweis University, Budapest, Hungary
- MTA-SE Laboratory of Molecular Physiology, Hungarian Academy of Sciences and Semmelweis University, Budapest, Hungary
- *Correspondence: Gábor Turu, ; László Hunyady,
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8
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Morales P, Navarro G, Gómez‐Autet M, Redondo L, Fernández‐Ruiz J, Pérez‐Benito L, Cordomí A, Pardo L, Franco R, Jagerovic N. Discovery of Homobivalent Bitopic Ligands of the Cannabinoid CB 2 Receptor*. Chemistry 2020; 26:15839-15842. [PMID: 32794211 PMCID: PMC7756656 DOI: 10.1002/chem.202003389] [Citation(s) in RCA: 17] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/19/2020] [Revised: 08/12/2020] [Indexed: 12/21/2022]
Abstract
Single chemical entities with potential to simultaneously interact with two binding sites are emerging strategies in medicinal chemistry. We have designed, synthesized and functionally characterized the first bitopic ligands for the CB2 receptor. These compounds selectively target CB2 versus CB1 receptors. Their binding mode was studied by molecular dynamic simulations and site-directed mutagenesis.
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Affiliation(s)
- Paula Morales
- Medicinal Chemistry InstituteSpanish Research CouncilMadridSpain
| | - Gemma Navarro
- Department of Biochemistry and Physiology, CIBERNEDFaculty of Pharmacy and Food SciencesUniversitat de BarcelonaBarcelonaSpain
| | - Marc Gómez‐Autet
- Laboratory of Computational Medicine, Biostatistics UnitFaculty of MedicineUniversitat Autónoma de BarcelonaBarcelonaSpain
| | - Laura Redondo
- Medicinal Chemistry InstituteSpanish Research CouncilMadridSpain
| | - Javier Fernández‐Ruiz
- Department of Biochemistry and Molecular Biology, CIBERNED, IRYCISFaculty of MedicineUniversidad Complutense de MadridMadridSpain
| | - Laura Pérez‐Benito
- Laboratory of Computational Medicine, Biostatistics UnitFaculty of MedicineUniversitat Autónoma de BarcelonaBarcelonaSpain
- Present address: Computational ChemistryJanssen Research & Development, Janssen Pharmaceutica N.V.Belgium
| | - Arnau Cordomí
- Laboratory of Computational Medicine, Biostatistics UnitFaculty of MedicineUniversitat Autónoma de BarcelonaBarcelonaSpain
| | - Leonardo Pardo
- Laboratory of Computational Medicine, Biostatistics UnitFaculty of MedicineUniversitat Autónoma de BarcelonaBarcelonaSpain
| | - Rafael Franco
- Department of Biochemistry and Physiology, CIBERNEDFaculty of Pharmacy and Food SciencesUniversitat de BarcelonaBarcelonaSpain
- Department of Biochemistry and Molecular Biology, CIBERNEDSchool of ChemistryUniversitat de BarcelonaBarcelonaSpain
| | - Nadine Jagerovic
- Medicinal Chemistry InstituteSpanish Research CouncilMadridSpain
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9
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Gonçalves ECD, Assis PM, Junqueira LA, Cola M, Santos ARS, Raposo NRB, Dutra RC. Citral Inhibits the Inflammatory Response and Hyperalgesia in Mice: The Role of TLR4, TLR2/Dectin-1, and CB2 Cannabinoid Receptor/ATP-Sensitive K + Channel Pathways. J Nat Prod 2020; 83:1190-1200. [PMID: 32150408 DOI: 10.1021/acs.jnatprod.9b01134] [Citation(s) in RCA: 19] [Impact Index Per Article: 4.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/27/2023]
Abstract
Citral ((2E)-3,7-dimethylocta-2,6-dienal), a bioactive component of lemongrass, inhibits oxidant activity, nuclear factor kappa B (NF-κB) activation, and cyclooxygenase-2 (COX-2) expression, even as it activates peroxisome proliferator-activated receptor (PPAR)-α and γ. Additionally, citral produces long-lasting inhibition of transient receptor potential (TRP) channels that are found in sensory neurons, such as TRPV1-3 and TRPM8, while it transiently blocks TRPV4 and TRPA1. Here, the effect of citral in experimental models of acute inflammation and hyperalgesia in mice, and the underlying citral mechanisms of action were investigated. ADMET properties and molecular targets were predicted using the online server. The immunomodulatory and antihyperalgesic effects of citral were evaluated, using mechanical and thermal stimuli, at different time-points on carrageenan, lipopolysaccharides (LPS), and zymosan-induced paw edema and hyperalgesia in mice. ADMET analysis ensures that the citral has not violated Lipinski's rule of five, indicating its safety consumption, and molecular target prediction software identified that citral is a potential fatty acid amide hydrolase (FAAH) inhibitor. Oral treatment with citral (50-300 mg/kg) significantly inhibited carrageenan-induced paw edema and thermal allodynia. Furthermore, citral modulated the inflammation induced by LPS and zymosan, toll-like receptor (TLR) 4, and TLR2/dectin-1 ligands, respectively. Moreover, pretreatment with cannabinoid receptor type 2 (CB2R) antagonists and ATP-sensitive K+ channel inhibitor, but not with a cannabinoid receptor type 1 (CB1R) antagonist, significantly reversed the anti-inflammatory effect of citral. Intriguingly, citral did not cause any relevant action in the central nervous system, and it was safe when assessed in a 14 day toxicity assay in male mice. Therefore, citral constitutes a promising, innovative, and safe molecule for the management of immunoinflammatory conditions and pain states.
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Affiliation(s)
- Elaine C D Gonçalves
- Laboratory of Autoimmunity and Immunopharmacology, Department of Health Sciences, Campus Araranguá, Universidade Federal de Santa Catarina, 88906-072, Araranguá, SC, Brazil
- Post-Graduate Program of Neuroscience, Center of Biological Sciences, Universidade Federal de Santa Catarina, 88040-900, Florianópolis, SC, Brazil
| | - Pollyana M Assis
- Center of Research and Innovation in Health Sciences (NUPICS), School of Pharmacy, Universidade Federal de Juiz de Fora, 36036-330, Juiz de Fora, MG, Brazil
| | - Laura A Junqueira
- Center of Research and Innovation in Health Sciences (NUPICS), School of Pharmacy, Universidade Federal de Juiz de Fora, 36036-330, Juiz de Fora, MG, Brazil
| | - Maíra Cola
- Laboratory of Autoimmunity and Immunopharmacology, Department of Health Sciences, Campus Araranguá, Universidade Federal de Santa Catarina, 88906-072, Araranguá, SC, Brazil
| | - Adair R S Santos
- Laboratory of Neurobiology of Pain and Inflammation, Department of Physiological Sciences, Center of Biological Sciences, Universidade Federal de Santa Catarina, 88040-900, Florianópolis, SC, Brazil
| | - Nadia R B Raposo
- Center of Research and Innovation in Health Sciences (NUPICS), School of Pharmacy, Universidade Federal de Juiz de Fora, 36036-330, Juiz de Fora, MG, Brazil
| | - Rafael C Dutra
- Laboratory of Autoimmunity and Immunopharmacology, Department of Health Sciences, Campus Araranguá, Universidade Federal de Santa Catarina, 88906-072, Araranguá, SC, Brazil
- Post-Graduate Program of Neuroscience, Center of Biological Sciences, Universidade Federal de Santa Catarina, 88040-900, Florianópolis, SC, Brazil
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10
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Peng Y, Zheng X, Fan Z, Zhou H, Zhu X, Wang G, Liu Z. Paeonol alleviates primary dysmenorrhea in mice via activating CB2R in the uterus. Phytomedicine 2020; 68:153151. [PMID: 32058234 DOI: 10.1016/j.phymed.2019.153151] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/11/2019] [Revised: 10/18/2019] [Accepted: 12/11/2019] [Indexed: 06/10/2023]
Abstract
BACKGROUND AND PURPOSE Primary dysmenorrhea is the most common gynaecologic problem in menstruating women and is characterized by spasmodic uterine contraction and pain symptoms associated with inflammatory disturbances. Paeonol is an active phytochemical component that has shown anti-inflammatory and analgesic effects in several animal models. The aim of this study was to explore whether paeonol is effective against dysmenorrhea and to investigate the potential mechanism of cannabinoid receptor signalling. EXPERIMENTAL APPROACH Dysmenorrhea was established by injecting oestradiol benzoate into female mice. The effects of paeonol on writhing time and latency, uterine pathology and inflammatory mediators were explored. Isolated uterine smooth muscle was used to evaluate the direct effect of paeonol on uterine contraction. KEY RESULTS The oral administration of paeonol reduced dysmenorrhea pain and PGE2 and TNF-α expression in the uterine tissues of mice, and paeonol was found to be distributed in lesions of the uterus. Paeonol almost completely inhibited oxytocin-, high potassium- and Ca2+-induced contractions in isolated uteri. Antagonists of CB2R (AM630) and the MAPK pathway (U0126), but not of CB1R (AM251), reversed the inhibitory effect of paeonol on uterine contraction. Paeonol significantly blocked L-type Ca2+ channels and calcium influx in uterine smooth muscle cells via CB2R. Molecular docking results showed that paeonol fits well with the binding site of CB2R. CONCLUSIONS AND IMPLICATIONS Paeonol partially acts through CB2R to restrain calcium influx and uterine contraction to alleviate dysmenorrhea in mice. These results suggest that paeonol has therapeutic potential for the treatment of dysmenorrhea.
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Affiliation(s)
- Yi Peng
- State Key Laboratory of Natural Medicines, China Pharmaceutical University, Nanjing, Jiangsu 210029, China
| | - Xiao Zheng
- State Key Laboratory of Natural Medicines, China Pharmaceutical University, Nanjing, Jiangsu 210029, China
| | - Zhiyi Fan
- Department of Pharmacy, Nanjing University of Chinese Medicine Affiliated Hospital, Nanjing, Jiangsu 210029, China
| | - Hongliang Zhou
- Department of Pharmacy, Nanjing University of Chinese Medicine Affiliated Hospital, Nanjing, Jiangsu 210029, China
| | - Xuanxuan Zhu
- Department of Pharmacy, Nanjing University of Chinese Medicine Affiliated Hospital, Nanjing, Jiangsu 210029, China
| | - Guangji Wang
- State Key Laboratory of Natural Medicines, China Pharmaceutical University, Nanjing, Jiangsu 210029, China.
| | - Zhihui Liu
- Department of Pharmacy, Nanjing University of Chinese Medicine Affiliated Hospital, Nanjing, Jiangsu 210029, China.
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11
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Linciano P, Citti C, Luongo L, Belardo C, Maione S, Vandelli MA, Forni F, Gigli G, Laganà A, Montone CM, Cannazza G. Isolation of a High-Affinity Cannabinoid for the Human CB1 Receptor from a Medicinal Cannabis sativa Variety: Δ 9-Tetrahydrocannabutol, the Butyl Homologue of Δ 9-Tetrahydrocannabinol. J Nat Prod 2020; 83:88-98. [PMID: 31891265 DOI: 10.1021/acs.jnatprod.9b00876] [Citation(s) in RCA: 33] [Impact Index Per Article: 8.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/10/2023]
Abstract
The butyl homologues of Δ9-tetrahydrocannabinol, Δ9-tetrahydrocannabutol (Δ9-THCB), and cannabidiol, cannabidibutol (CBDB), were isolated from a medicinal Cannabis sativa variety (FM2) inflorescence. Appropriate spectroscopic and spectrometric characterization, including NMR, UV, IR, ECD, and HRMS, was carried out on both cannabinoids. The chemical structures and absolute configurations of the isolated cannabinoids were confirmed by comparison with the spectroscopic data of the respective compounds obtained by stereoselective synthesis. The butyl homologue of Δ9-THC, Δ9-THCB, showed an affinity for the human CB1 (Ki = 15 nM) and CB2 receptors (Ki = 51 nM) comparable to that of (-)-trans-Δ9-THC. Docking studies suggested the key bonds responsible for THC-like binding affinity for the CB1 receptor. The formalin test in vivo was performed on Δ9-THCB in order to reveal possible analgesic and anti-inflammatory properties. The tetrad test in mice showed a partial agonistic activity of Δ9-THCB toward the CB1 receptor.
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MESH Headings
- Analgesics/pharmacology
- Animals
- Cannabidiol/chemistry
- Cannabinoids/chemistry
- Cannabinoids/isolation & purification
- Cannabis/chemistry
- Dronabinol/chemistry
- Dronabinol/isolation & purification
- Humans
- Medical Marijuana
- Mice
- Molecular Structure
- Receptor, Cannabinoid, CB1/chemistry
- Receptor, Cannabinoid, CB1/isolation & purification
- Receptor, Cannabinoid, CB1/metabolism
- Receptor, Cannabinoid, CB2/chemistry
- Receptor, Cannabinoid, CB2/metabolism
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Affiliation(s)
- Pasquale Linciano
- Department of Life Sciences , University of Modena and Reggio Emilia , Via Campi 103 , 41125 Modena , Italy
| | - Cinzia Citti
- Department of Life Sciences , University of Modena and Reggio Emilia , Via Campi 103 , 41125 Modena , Italy
- Mediteknology s.r.l. , Via Arnesano , 73100 Lecce , Italy
- CNR NANOTEC , Campus Ecotekne, Via Monteroni , 73100 Lecce , Italy
| | - Livio Luongo
- Department of Experimental Medicine, Division of Pharmacology , Università della Campania "L. Vanvitelli" , Via Santa Maria di Costantinopoli 16 , 80138 Naples , Italy
| | - Carmela Belardo
- Department of Experimental Medicine, Division of Pharmacology , Università della Campania "L. Vanvitelli" , Via Santa Maria di Costantinopoli 16 , 80138 Naples , Italy
| | - Sabatino Maione
- Department of Experimental Medicine, Division of Pharmacology , Università della Campania "L. Vanvitelli" , Via Santa Maria di Costantinopoli 16 , 80138 Naples , Italy
| | - Maria Angela Vandelli
- Department of Life Sciences , University of Modena and Reggio Emilia , Via Campi 103 , 41125 Modena , Italy
| | - Flavio Forni
- Department of Life Sciences , University of Modena and Reggio Emilia , Via Campi 103 , 41125 Modena , Italy
| | - Giuseppe Gigli
- CNR NANOTEC , Campus Ecotekne, Via Monteroni , 73100 Lecce , Italy
| | - Aldo Laganà
- CNR NANOTEC , Campus Ecotekne, Via Monteroni , 73100 Lecce , Italy
- Department of Chemistry , Sapienza University of Rome , Piazzale Aldo Moro 5 , 00185 Rome , Italy
| | - Carmela Maria Montone
- Department of Chemistry , Sapienza University of Rome , Piazzale Aldo Moro 5 , 00185 Rome , Italy
| | - Giuseppe Cannazza
- Department of Life Sciences , University of Modena and Reggio Emilia , Via Campi 103 , 41125 Modena , Italy
- CNR NANOTEC , Campus Ecotekne, Via Monteroni , 73100 Lecce , Italy
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12
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Beckner RL, Zoubak L, Hines KG, Gawrisch K, Yeliseev AA. Probing thermostability of detergent-solubilized CB 2 receptor by parallel G protein-activation and ligand-binding assays. J Biol Chem 2020; 295:181-190. [PMID: 31776188 PMCID: PMC6952600 DOI: 10.1074/jbc.ra119.010696] [Citation(s) in RCA: 8] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/16/2019] [Revised: 11/22/2019] [Indexed: 11/06/2022] Open
Abstract
G protein-coupled receptors (GPCRs) comprise a large class of integral membrane proteins involved in the regulation of a broad spectrum of physiological processes and are a major target for pharmaceutical drug development. Structural studies can help advance the rational design of novel specific pharmaceuticals that target GPCRs, but such studies require expression of significant quantities of these proteins in pure, homogenous, and sufficiently stable form. An essential precursor for these structural studies is an assessment of protein stability under experimental conditions. Here we report that solubilization of a GPCR, type II cannabinoid receptor CB2, in a Façade detergent enables radioligand thermostability assessments of this receptor with low background from nonspecific interactions with lipophilic cannabinoid ligand. Furthermore, this detergent is compatible with a [35S]GTPγS radionucleotide exchange assay measuring guanine exchange factor activity that can be applied after heat treatment to further assess receptor thermostability. We demonstrate that both assays can be utilized to determine differences in CB2 thermostability caused by mutations, detergent composition, and the presence of stabilizing ligands. We report that a constitutively active CB2 variant has higher thermostability than the WT receptor, a result that differs from a previous thermostability assessment of the analogous CB1 mutation. We conclude that both ligand-binding and activity-based assays under optimized detergent conditions can support selection of thermostable variants of experimentally demanding GPCRs.
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Affiliation(s)
- Ryan L Beckner
- NIAAA, National Institutes of Health, Bethesda, Maryland 208521
| | | | - Kirk G Hines
- NIAAA, National Institutes of Health, Bethesda, Maryland 208521
| | - Klaus Gawrisch
- NIAAA, National Institutes of Health, Bethesda, Maryland 208521
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13
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Alapafuja SO, Nikas SP, Ho TC, Tong F, Benchama O, Makriyannis A. Chain Substituted Cannabilactones with Selectivity for the CB2 Cannabinoid Receptor. Molecules 2019; 24:E3559. [PMID: 31581433 PMCID: PMC6804212 DOI: 10.3390/molecules24193559] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/23/2019] [Revised: 09/25/2019] [Accepted: 09/27/2019] [Indexed: 11/21/2022] Open
Abstract
In earlier work, we reported a novel class of CB2 selective ligands namely cannabilactones. These compounds carry a dimethylheptyl substituent at C3, which is typical for synthetic cannabinoids. In the current study with the focus on the pharmacophoric side chain at C3 we explored the effect of replacing the C1'-gem-dimethyl group with the bulkier cyclopentyl ring, and, we also probed the chain's length and terminal carbon substitution with bromo or cyano groups. One of the analogs synthesized namely 6-[1-(1,9-dihydroxy-6-oxo-6H-benzo[c]chromen-3-yl) cyclopentyl] hexanenitrile (AM4346) has very high affinity (Ki = 4.9 nM) for the mouse CB2 receptor (mCB2) and 131-fold selectivity for that target over the rat CB1 (rCB1). The species difference in the affinities of AM4346 between the mouse (m) and the human (h) CB2 receptors is reduced when compared to our first-generation cannabilactones. In the cyclase assay, our lead compound was found to be a highly potent and efficacious hCB2 receptor agonist (EC50 = 3.7 ± 1.5 nM, E(max) = 89%). We have also extended our structure-activity relationship (SAR) studies to include biphenyl synthetic intermediates that mimic the structure of the phytocannabinoid cannabinodiol.
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Affiliation(s)
- Shakiru O Alapafuja
- Center for Drug Discovery and Department of Pharmaceutical Sciences, Northeastern University, Boston, MA 02115, USA.
| | - Spyros P Nikas
- Center for Drug Discovery and Department of Pharmaceutical Sciences, Northeastern University, Boston, MA 02115, USA.
| | - Thanh C Ho
- Center for Drug Discovery and Department of Pharmaceutical Sciences, Northeastern University, Boston, MA 02115, USA.
| | - Fei Tong
- Center for Drug Discovery and Department of Pharmaceutical Sciences, Northeastern University, Boston, MA 02115, USA.
| | - Othman Benchama
- Center for Drug Discovery and Department of Pharmaceutical Sciences, Northeastern University, Boston, MA 02115, USA.
| | - Alexandros Makriyannis
- Center for Drug Discovery and Department of Pharmaceutical Sciences, Northeastern University, Boston, MA 02115, USA.
- Department of Chemistry & Chemical Biology, Northeastern University, Boston, MA 02115, USA.
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14
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Porter RF, Szczesniak AM, Toguri JT, Gebremeskel S, Johnston B, Lehmann C, Fingerle J, Rothenhäusler B, Perret C, Rogers-Evans M, Kimbara A, Nettekoven M, Guba W, Grether U, Ullmer C, Kelly MEM. Selective Cannabinoid 2 Receptor Agonists as Potential Therapeutic Drugs for the Treatment of Endotoxin-Induced Uveitis. Molecules 2019; 24:molecules24183338. [PMID: 31540271 PMCID: PMC6767236 DOI: 10.3390/molecules24183338] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/05/2019] [Revised: 09/04/2019] [Accepted: 09/11/2019] [Indexed: 12/21/2022] Open
Abstract
(1) Background: The cannabinoid 2 receptor (CB2R) is a promising anti-inflammatory drug target and development of selective CB2R ligands may be useful for treating sight-threatening ocular inflammation. (2) Methods: This study examined the pharmacology of three novel chemically-diverse selective CB2R ligands: CB2R agonists, RO6871304, and RO6871085, as well as a CB2R inverse agonist, RO6851228. In silico molecular modelling and in vitro cell-based receptor assays were used to verify CB2R interactions, binding, cell signaling (ß-arrestin and cAMP) and early absorption, distribution, metabolism, excretion, and toxicology (ADMET) profiling of these receptor ligands. All ligands were evaluated for their efficacy to modulate leukocyte-neutrophil activity, in comparison to the reported CB2R ligand, HU910, using an in vivo mouse model of endotoxin-induced uveitis (EIU) in wild-type (WT) and CB2R-/- mice. The actions of RO6871304 on neutrophil migration and adhesion were examined in vitro using isolated neutrophils from WT and CB2R-/- mice, and in vivo in WT mice with EIU using adoptive transfer of WT and CB2R-/- neutrophils, respectively. (3) Results: Molecular docking studies indicated that RO6871304 and RO6871085 bind to the orthosteric site of CB2R. Binding studies and cell signaling assays for RO6871304 and RO6871085 confirmed high-affinity binding to CB2R and selectivity for CB2R > CB1R, with both ligands acting as full agonists in cAMP and ß-arrestin assays (EC50s in low nM range). When tested in EIU, topical application of RO6871304 and RO6871085 decreased leukocyte-endothelial adhesion and this effect was antagonized by the inverse agonist, RO6851228. The CB2R agonist, RO6871304, decreased in vitro neutrophil migration of WT neutrophils but not neutrophils from CB2R-/-, and attenuated adhesion of adoptively-transferred leukocytes in EIU. (4) Conclusions: These unique ligands are potent and selective for CB2R and have good immunomodulating actions in the eye. RO6871304 and RO6871085, as well as HU910, decreased leukocyte adhesion in EIU through inhibition of resident ocular immune cells. The data generated with these three structurally-diverse and highly-selective CB2R agonists support selective targeting of CB2R for treating ocular inflammatory diseases.
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MESH Headings
- Animals
- Anti-Inflammatory Agents/administration & dosage
- Anti-Inflammatory Agents/chemistry
- Anti-Inflammatory Agents/pharmacology
- Cannabinoid Receptor Agonists/administration & dosage
- Cannabinoid Receptor Agonists/chemistry
- Cannabinoid Receptor Agonists/pharmacology
- Cell Adhesion/drug effects
- Cells, Cultured
- Disease Models, Animal
- Endotoxins/adverse effects
- Leukocytes/drug effects
- Leukocytes/metabolism
- Male
- Mice
- Mice, Knockout
- Models, Molecular
- Molecular Docking Simulation
- Molecular Structure
- Neutrophils/drug effects
- Neutrophils/metabolism
- Receptor, Cannabinoid, CB2/antagonists & inhibitors
- Receptor, Cannabinoid, CB2/chemistry
- Receptor, Cannabinoid, CB2/genetics
- Signal Transduction
- Uveitis/chemically induced
- Uveitis/drug therapy
- Uveitis/immunology
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Affiliation(s)
| | | | - James Thomas Toguri
- Department of Pharmacology, Dalhousie University, Halifax, NS B3H 4R2, Canada.
| | - Simon Gebremeskel
- Department of Microbiology and Immunology, Dalhousie University, Halifax, NS B3H 4R2, Canada.
| | - Brent Johnston
- Department of Microbiology and Immunology, Dalhousie University, Halifax, NS B3H 4R2, Canada.
- Department of Pediatrics, Dalhousie University, Halifax, NS B3H 4R2, Canada.
| | - Christian Lehmann
- Department of Pharmacology, Dalhousie University, Halifax, NS B3H 4R2, Canada.
- Department of Microbiology and Immunology, Dalhousie University, Halifax, NS B3H 4R2, Canada.
- Department of Anesthesia, Pain Management and Perioperative Care, Dalhousie University, Halifax, NS B3H 4R2, Canada.
| | - Jürgen Fingerle
- Roche Innovation Center Basel, F. Hoffmann-La Roche Ltd., 4070 Basel, Switzerland.
| | - Benno Rothenhäusler
- Roche Innovation Center Basel, F. Hoffmann-La Roche Ltd., 4070 Basel, Switzerland.
| | - Camille Perret
- Roche Innovation Center Basel, F. Hoffmann-La Roche Ltd., 4070 Basel, Switzerland.
| | - Mark Rogers-Evans
- Roche Innovation Center Basel, F. Hoffmann-La Roche Ltd., 4070 Basel, Switzerland.
| | - Atsushi Kimbara
- Roche Innovation Center Basel, F. Hoffmann-La Roche Ltd., 4070 Basel, Switzerland.
| | - Matthias Nettekoven
- Roche Innovation Center Basel, F. Hoffmann-La Roche Ltd., 4070 Basel, Switzerland.
| | - Wolfgang Guba
- Roche Innovation Center Basel, F. Hoffmann-La Roche Ltd., 4070 Basel, Switzerland.
| | - Uwe Grether
- Roche Innovation Center Basel, F. Hoffmann-La Roche Ltd., 4070 Basel, Switzerland.
| | - Christoph Ullmer
- Roche Innovation Center Basel, F. Hoffmann-La Roche Ltd., 4070 Basel, Switzerland.
| | - Melanie E M Kelly
- Department of Pharmacology, Dalhousie University, Halifax, NS B3H 4R2, Canada.
- Department of Anesthesia, Pain Management and Perioperative Care, Dalhousie University, Halifax, NS B3H 4R2, Canada.
- Department of Ophthalmology and Visual Sciences, Dalhousie University, Halifax, NS B3H 2Y9, Canada.
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15
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Vijayakumar S, Manogar P, Prabhu S, Pugazhenthi M, Praseetha PK. A pharmacoinformatic approach on Cannabinoid receptor 2 (CB2) and different small molecules: Homology modelling, molecular docking, MD simulations, drug designing and ADME analysis. Comput Biol Chem 2018; 78:95-107. [PMID: 30500557 DOI: 10.1016/j.compbiolchem.2018.11.013] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/24/2018] [Revised: 11/14/2018] [Accepted: 11/16/2018] [Indexed: 11/20/2022]
Abstract
CB2 receptor belongs to the family of G-protein coupled receptors (GPCRs), which extensively controls a range of pointer transduction. CB2 plays an essential role in the immune system. It also associates in the pathology of different ailment conditions. In this scenario, the synthetic drugs are inducing side effects to the human beings after the drug use. Therefore, this study is seeking novel alternate drug molecules with least side effects than conventional drugs. The alternative drug molecules were chosen from the natural sources. These molecules were selected from cyanobacteria with the help of earlier research findings. The target and ligand molecules were obtained from recognized databases. The bioactive molecules are selected from various cyanobacterial species, which are selected by their biological and pharmacological properties, after, which we incorporated to the crucial findings such as homology modelling, molecular docking, MD simulations along with absorption, distribution, metabolism, and excretion (ADME) analysis. Initially, the homology modelling was performed to frame the target from unknown sequences of CB2, which revealed 44% of similarities and 66% of identities with the A2A receptor. Subsequently, the CB2 protein molecule has docked with already known and prepared bioactive molecules, agonists and antagonist complex. In the present study, the agonists (5) and antagonist (1) were also taken for comparing the results with natural molecules. At the end of the docking analysis, the cyanobacterial molecules and an antagonist TNC-201 are revealed better docking scores with well binding contacts than the agonists. Especially, the usneoidone shows better results than other cyanobacterial molecules, and it is very close docking scores with that of TCN-201. Therefore, the usneoidone has incorporated to MD simulation with Cannabinoid receptors 2 (CB2). In MD simulations, the complex (CB2 and usneoidone) reveals better stability in 30 ns. Based on the computational outcome, we concluded that usneoidone is an effectual and appropriate drug candidate for activating CB2 receptors and it will be serving as a better component for the complications of CB2. Moreover, these computational approaches can be motivated to discover novel drug candidates in the pharmacological and healthcare sectors.
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Affiliation(s)
- S Vijayakumar
- Computational Phytochemistry Lab, Department of Botany and Microbiology, AVVM Sri Pushpam College (Autonomous), Poondi, Thanjavur, Tamil Nadu, India.
| | - P Manogar
- Computational Phytochemistry Lab, Department of Botany and Microbiology, AVVM Sri Pushpam College (Autonomous), Poondi, Thanjavur, Tamil Nadu, India
| | - S Prabhu
- Computational Phytochemistry Lab, Department of Botany and Microbiology, AVVM Sri Pushpam College (Autonomous), Poondi, Thanjavur, Tamil Nadu, India
| | - M Pugazhenthi
- Department of Chemistry, AVVM Sri Pushpam College (Autonomous) Poondi, Thanjavur (Dist), Tamil Nadu, India
| | - P K Praseetha
- Department of Nanotechnology Noorul Islam Centre for Higher Education Kumaracoil, Kanyakumari district Tamil Nadu, 629180, India
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16
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Floresta G, Apirakkan O, Rescifina A, Abbate V. Discovery of High-Affinity Cannabinoid Receptors Ligands through a 3D-QSAR Ushered by Scaffold-Hopping Analysis. Molecules 2018; 23:molecules23092183. [PMID: 30200181 PMCID: PMC6225167 DOI: 10.3390/molecules23092183] [Citation(s) in RCA: 24] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/23/2018] [Revised: 08/26/2018] [Accepted: 08/28/2018] [Indexed: 01/08/2023] Open
Abstract
Two 3D quantitative structure–activity relationships (3D-QSAR) models for predicting Cannabinoid receptor 1 and 2 (CB1 and CB2) ligands have been produced by way of creating a practical tool for the drug-design and optimization of CB1 and CB2 ligands. A set of 312 molecules have been used to build the model for the CB1 receptor, and a set of 187 molecules for the CB2 receptor. All of the molecules were recovered from the literature among those possessing measured Ki values, and Forge was used as software. The present model shows high and robust predictive potential, confirmed by the quality of the statistical analysis, and an adequate descriptive capability. A visual understanding of the hydrophobic, electrostatic, and shaping features highlighting the principal interactions for the CB1 and CB2 ligands was achieved with the construction of 3D maps. The predictive capabilities of the model were then used for a scaffold-hopping study of two selected compounds, with the generation of a library of new compounds with high affinity for the two receptors. Herein, we report two new 3D-QSAR models that comprehend a large number of chemically different CB1 and CB2 ligands and well account for the individual ligand affinities. These features will facilitate the recognition of new potent and selective molecules for CB1 and CB2 receptors.
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MESH Headings
- Cannabinoid Receptor Agonists/chemistry
- Cannabinoid Receptor Agonists/metabolism
- Cannabinoid Receptor Antagonists/chemistry
- Cannabinoid Receptor Antagonists/metabolism
- Drug Design
- Hydrophobic and Hydrophilic Interactions
- Ligands
- Models, Molecular
- Molecular Conformation
- Molecular Docking Simulation
- Molecular Dynamics Simulation
- Molecular Structure
- Protein Binding
- Quantitative Structure-Activity Relationship
- Receptor, Cannabinoid, CB1/chemistry
- Receptor, Cannabinoid, CB1/metabolism
- Receptor, Cannabinoid, CB2/chemistry
- Receptor, Cannabinoid, CB2/metabolism
- Receptors, Cannabinoid/chemistry
- Receptors, Cannabinoid/metabolism
- Software
- Static Electricity
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Affiliation(s)
- Giuseppe Floresta
- Department of Drug Sciences, University of Catania, V.le A. Doria, 95125 Catania, Italy.
- Department of Chemical Sciences, University of Catania, V.le A. Doria, 95125 Catania, Italy.
- Institute of Pharmaceutical Science, King's College London, Stamford Street, London SE1 9NH, UK.
| | - Orapan Apirakkan
- King's Forensics, School of Population Health & Environmental Sciences, King's College London, Franklin-Wilkins Building, 150 Stamford Street, London SE1 9NH, UK.
| | - Antonio Rescifina
- Department of Drug Sciences, University of Catania, V.le A. Doria, 95125 Catania, Italy.
| | - Vincenzo Abbate
- King's Forensics, School of Population Health & Environmental Sciences, King's College London, Franklin-Wilkins Building, 150 Stamford Street, London SE1 9NH, UK.
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17
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Yeliseev A, Zoubak L, Schmidt TGM. Application of Strep-Tactin XT for affinity purification of Twin-Strep-tagged CB 2, a G protein-coupled cannabinoid receptor. Protein Expr Purif 2017; 131:109-118. [PMID: 27867058 PMCID: PMC5406253 DOI: 10.1016/j.pep.2016.11.006] [Citation(s) in RCA: 19] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/18/2016] [Revised: 11/02/2016] [Accepted: 11/04/2016] [Indexed: 11/29/2022]
Abstract
Human cannabinoid receptor CB2 belongs to the class A of G protein-coupled receptor (GPCR). CB2 is predominantly expressed in membranes of cells of immune origin and is implicated in regulation of metabolic pathways of inflammation, neurodegenerative disorders and pain sensing. High resolution structural studies of CB2 require milligram quantities of purified, structurally intact protein. While we previously reported on the methodology for expression of the recombinant CB2 and its stabilization in a functional state, here we describe an efficient protocol for purification of this protein using the Twin-Strep-tag/Strep-Tactin XT system. To improve the affinity of interaction of the recombinant CB2 with the resin, the double repeat of the Strep-tag (a sequence of eight amino acids WSHPQFEK), named the Twin-Strep-tag was attached either to the N- or C-terminus of CB2 via a short linker, and the recombinant protein was expressed in cytoplasmic membranes of E. coli as a fusion with the N-terminal maltose binding protein (MBP). The CB2 was isolated at high purity from dilute solutions containing high concentrations of detergents, glycerol and salts, by capturing onto the Strep-Tactin XT resin, and was eluted from the resin under mild conditions upon addition of biotin. Surface plasmon resonance studies performed on the purified protein demonstrate the high affinity of interaction between the Twin-Strep-tag fused to the CB2 and Strep-Tactin XT with an estimated Kd in the low nanomolar range. The affinity of binding did not vary significantly in response to the position of the tag at either N- or C-termini of the fusion. The binding capacity of the resin was several-fold higher for the tag located at the N-terminus of the protein as opposed to the C-terminus- or middle of the fusion. The variation in the length of the linker between the double repeats of the Strep-tag from 6 to 12 amino acid residues did not significantly affect the binding. The novel purification protocol reported here enables efficient isolation of a recombinant GPCR expressed at low titers in host cells. This procedure is suitable for preparation of milligram quantities of stable isotope-labelled receptor for high-resolution NMR studies.
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MESH Headings
- Chromatography, Affinity/methods
- Escherichia coli
- Gene Expression
- Humans
- Nuclear Magnetic Resonance, Biomolecular
- Receptor, Cannabinoid, CB2/biosynthesis
- Receptor, Cannabinoid, CB2/chemistry
- Receptor, Cannabinoid, CB2/genetics
- Receptor, Cannabinoid, CB2/isolation & purification
- Recombinant Fusion Proteins/biosynthesis
- Recombinant Fusion Proteins/chemistry
- Recombinant Fusion Proteins/genetics
- Recombinant Fusion Proteins/isolation & purification
- Surface Plasmon Resonance
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Affiliation(s)
- Alexei Yeliseev
- National Institute on Alcoholism and Alcohol Abuse, National Institutes of Health, 5625 Fishers Lane, Room 3N17, Rockville, MD, 20892, USA.
| | - Lioudmila Zoubak
- National Institute on Alcoholism and Alcohol Abuse, National Institutes of Health, 5625 Fishers Lane, Room 3N17, Rockville, MD, 20892, USA
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18
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Hu J, Feng Z, Ma S, Zhang Y, Tong Q, Alqarni MH, Gou X, Xie XQ. Difference and Influence of Inactive and Active States of Cannabinoid Receptor Subtype CB2: From Conformation to Drug Discovery. J Chem Inf Model 2016; 56:1152-63. [PMID: 27186994 PMCID: PMC5395206 DOI: 10.1021/acs.jcim.5b00739] [Citation(s) in RCA: 26] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/10/2023]
Abstract
Cannabinoid receptor 2 (CB2), a G protein-coupled receptor (GPCR), is a promising target for the treatment of neuropathic pain, osteoporosis, immune system, cancer, and drug abuse. The lack of an experimental three-dimensional CB2 structure has hindered not only the development of studies of conformational differences between the inactive and active CB2 but also the rational discovery of novel functional compounds targeting CB2. In this work, we constructed models of both inactive and active CB2 by homology modeling. Then we conducted two comparative 100 ns molecular dynamics (MD) simulations on the two systems-the active CB2 bound with both the agonist and G protein and the inactive CB2 bound with inverse agonist-to analyze the conformational difference of CB2 proteins and the key residues involved in molecular recognition. Our results showed that the inactive CB2 and the inverse agonist remained stable during the MD simulation. However, during the MD simulations, we observed dynamical details about the breakdown of the "ionic lock" between R131(3.50) and D240(6.30) as well as the outward/inward movements of transmembrane domains of the active CB2 that bind with G proteins and agonist (TM5, TM6, and TM7). All of these results are congruent with the experimental data and recent reports. Moreover, our results indicate that W258(6.48) in TM6 and residues in TM4 (V164(4.56)-L169(4.61)) contribute greatly to the binding of the agonist on the basis of the binding energy decomposition, while residues S180-F183 in extracellular loop 2 (ECL2) may be of importance in recognition of the inverse agonist. Furthermore, pharmacophore modeling and virtual screening were carried out for the inactive and active CB2 models in parallel. Among all 10 hits, two compounds exhibited novel scaffolds and can be used as novel chemical probes for future studies of CB2. Importantly, our studies show that the hits obtained from the inactive CB2 model mainly act as inverse agonist(s) or neutral antagonist(s) at low concentration. Moreover, the hit from the active CB2 model also behaves as a neutral antagonist at low concentration. Our studies provide new insight leading to a better understanding of the structural and conformational differences between two states of CB2 and illuminate the effects of structure on virtual screening and drug design.
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Affiliation(s)
- Jianping Hu
- Department of Pharmaceutical Sciences and Computational Chemical Genomics Screening Center, School of Pharmacy, NIH National Center of Excellence for Computational Drug Abuse Research, Drug Discovery Institute, and Department of Computational Biology and Structural Biology, School of Medicine, University of Pittsburgh, Pittsburgh, Pennsylvania 15260, United States
- College of Chemistry, Leshan Normal University, Leshan, Sichuan 614004, China
- School of Pharmacy and Bioengineering; Key Laboratory of Medicinal and Edible Plants Resources Development, Chengdu University, Chengdu, Sichuan 610106, China
| | - Zhiwei Feng
- Department of Pharmaceutical Sciences and Computational Chemical Genomics Screening Center, School of Pharmacy, NIH National Center of Excellence for Computational Drug Abuse Research, Drug Discovery Institute, and Department of Computational Biology and Structural Biology, School of Medicine, University of Pittsburgh, Pittsburgh, Pennsylvania 15260, United States
| | - Shifan Ma
- Department of Pharmaceutical Sciences and Computational Chemical Genomics Screening Center, School of Pharmacy, NIH National Center of Excellence for Computational Drug Abuse Research, Drug Discovery Institute, and Department of Computational Biology and Structural Biology, School of Medicine, University of Pittsburgh, Pittsburgh, Pennsylvania 15260, United States
| | - Yu Zhang
- Department of Pharmaceutical Sciences and Computational Chemical Genomics Screening Center, School of Pharmacy, NIH National Center of Excellence for Computational Drug Abuse Research, Drug Discovery Institute, and Department of Computational Biology and Structural Biology, School of Medicine, University of Pittsburgh, Pittsburgh, Pennsylvania 15260, United States
| | - Qin Tong
- Department of Pharmaceutical Sciences and Computational Chemical Genomics Screening Center, School of Pharmacy, NIH National Center of Excellence for Computational Drug Abuse Research, Drug Discovery Institute, and Department of Computational Biology and Structural Biology, School of Medicine, University of Pittsburgh, Pittsburgh, Pennsylvania 15260, United States
| | - Mohammed Hamed Alqarni
- Department of Pharmaceutical Sciences and Computational Chemical Genomics Screening Center, School of Pharmacy, NIH National Center of Excellence for Computational Drug Abuse Research, Drug Discovery Institute, and Department of Computational Biology and Structural Biology, School of Medicine, University of Pittsburgh, Pittsburgh, Pennsylvania 15260, United States
| | - Xiaojun Gou
- School of Pharmacy and Bioengineering; Key Laboratory of Medicinal and Edible Plants Resources Development, Chengdu University, Chengdu, Sichuan 610106, China
| | - Xiang-Qun Xie
- Department of Pharmaceutical Sciences and Computational Chemical Genomics Screening Center, School of Pharmacy, NIH National Center of Excellence for Computational Drug Abuse Research, Drug Discovery Institute, and Department of Computational Biology and Structural Biology, School of Medicine, University of Pittsburgh, Pittsburgh, Pennsylvania 15260, United States
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19
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Gianella-Borradori M, Christou I, Bataille CJR, Cross RL, Wynne GM, Greaves DR, Russell AJ. Ligand-based virtual screening identifies a family of selective cannabinoid receptor 2 agonists. Bioorg Med Chem 2015; 23:241-63. [PMID: 25487422 PMCID: PMC4346271 DOI: 10.1016/j.bmc.2014.11.002] [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] [MESH Headings] [Grants] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/01/2014] [Revised: 10/31/2014] [Accepted: 11/01/2014] [Indexed: 11/17/2022]
Abstract
The cannabinoid receptor 2 (CB2R) has been linked with the regulation of inflammation, and selective receptor activation has been proposed as a target for the treatment of a range of inflammatory diseases such as atherosclerosis and arthritis. In order to identify selective CB2R agonists with appropriate physicochemical and ADME properties for future evaluation in vivo, we first performed a ligand-based virtual screen. Subsequent medicinal chemistry optimisation studies led to the identification of a new class of selective CB2R agonists. Several examples showed high levels of activity (EC50<200 nM) and binding affinity (Ki<200 nM) for the CB2R, and no detectable activity at the CB1R. The most promising example, DIAS2, also showed favourable in vitro metabolic stability and absorption properties along with a clean selectivity profile when evaluated against a panel of GPCRs and kinases.
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Affiliation(s)
- Matteo Gianella-Borradori
- Department of Chemistry, Chemistry Research Laboratory, University of Oxford, Mansfield Road, Oxford OX1 3TA, UK
| | - Ivy Christou
- Sir William Dunn School of Pathology, South Parks Road, Oxford OX1 3RE, UK
| | - Carole J R Bataille
- Department of Chemistry, Chemistry Research Laboratory, University of Oxford, Mansfield Road, Oxford OX1 3TA, UK
| | - Rebecca L Cross
- Department of Chemistry, Chemistry Research Laboratory, University of Oxford, Mansfield Road, Oxford OX1 3TA, UK
| | - Graham M Wynne
- Department of Chemistry, Chemistry Research Laboratory, University of Oxford, Mansfield Road, Oxford OX1 3TA, UK
| | - David R Greaves
- Sir William Dunn School of Pathology, South Parks Road, Oxford OX1 3RE, UK.
| | - Angela J Russell
- Department of Chemistry, Chemistry Research Laboratory, University of Oxford, Mansfield Road, Oxford OX1 3TA, UK; Department of Pharmacology, University of Oxford, Mansfield Road, Oxford OX1 3QT, UK.
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20
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Feng Z, Alqarni MH, Yang P, Tong Q, Chowdhury A, Wang L, Xie XQ. Modeling, molecular dynamics simulation, and mutation validation for structure of cannabinoid receptor 2 based on known crystal structures of GPCRs. J Chem Inf Model 2014; 54:2483-99. [PMID: 25141027 PMCID: PMC4170816 DOI: 10.1021/ci5002718] [Citation(s) in RCA: 76] [Impact Index Per Article: 7.6] [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: 05/06/2014] [Indexed: 12/29/2022]
Abstract
The cannabinoid receptor 2 (CB2) plays an important role in the immune system. Although a few of GPCRs crystallographic structures have been reported, it is still challenging to obtain functional transmembrane proteins and high resolution X-ray crystal structures, such as for the CB2 receptor. In the present work, we used 10 reported crystal structures of GPCRs which had high sequence identities with CB2 to construct homology-based comparative CB2 models. We applied these 10 models to perform a prescreen by using a training set consisting of 20 CB2 active compounds and 980 compounds randomly selected from the National Cancer Institute (NCI) database. We then utilized the known 170 cannabinoid receptor 1 (CB1) or CB2 selective compounds for further validation. Based on the docking results, we selected one CB2 model (constructed by β1AR) that was most consistent with the known experimental data, revealing that the defined binding pocket in our CB2 model was well-correlated with the training and testing data studies. Importantly, we identified a potential allosteric binding pocket adjacent to the orthosteric ligand-binding site, which is similar to the reported allosteric pocket for sodium ion Na(+) in the A2AAR and the δ-opioid receptor. Our studies in correlation of our data with others suggested that sodium may reduce the binding affinities of endogenous agonists or its analogs to CB2. We performed a series of docking studies to compare the important residues in the binding pockets of CB2 with CB1, including antagonist, agonist, and our CB2 neutral compound (neutral antagonist) XIE35-1001. Then, we carried out 50 ns molecular dynamics (MD) simulations for the CB2 docked with SR144528 and CP55940, respectively. We found that the conformational changes of CB2 upon antagonist/agonist binding were congruent with recent reports of those for other GPCRs. Based on these results, we further examined one known residue, Val113(3.32), and predicted two new residues, Phe183 in ECL2 and Phe281(7.35), that were important for SR144528 and CP55940 binding to CB2. We then performed site-directed mutation experimental study for these residues and validated the predictions by radiometric binding affinity assay.
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Affiliation(s)
- Zhiwei Feng
- Department
of Pharmaceutical Sciences and Computational Chemical
Genomics Screening Center, School of Pharmacy, Computational Drug Abuse Research
Center, Drug Discovery Institute, and Department of Computational Biology and Department
of Structural Biology, University of Pittsburgh, Pittsburgh, Pennsylvania 15261, United States
| | - Mohammed Hamed Alqarni
- Department
of Pharmaceutical Sciences and Computational Chemical
Genomics Screening Center, School of Pharmacy, Computational Drug Abuse Research
Center, Drug Discovery Institute, and Department of Computational Biology and Department
of Structural Biology, University of Pittsburgh, Pittsburgh, Pennsylvania 15261, United States
| | - Peng Yang
- Department
of Pharmaceutical Sciences and Computational Chemical
Genomics Screening Center, School of Pharmacy, Computational Drug Abuse Research
Center, Drug Discovery Institute, and Department of Computational Biology and Department
of Structural Biology, University of Pittsburgh, Pittsburgh, Pennsylvania 15261, United States
| | - Qin Tong
- Department
of Pharmaceutical Sciences and Computational Chemical
Genomics Screening Center, School of Pharmacy, Computational Drug Abuse Research
Center, Drug Discovery Institute, and Department of Computational Biology and Department
of Structural Biology, University of Pittsburgh, Pittsburgh, Pennsylvania 15261, United States
| | - Ananda Chowdhury
- Department
of Pharmaceutical Sciences and Computational Chemical
Genomics Screening Center, School of Pharmacy, Computational Drug Abuse Research
Center, Drug Discovery Institute, and Department of Computational Biology and Department
of Structural Biology, University of Pittsburgh, Pittsburgh, Pennsylvania 15261, United States
| | - Lirong Wang
- Department
of Pharmaceutical Sciences and Computational Chemical
Genomics Screening Center, School of Pharmacy, Computational Drug Abuse Research
Center, Drug Discovery Institute, and Department of Computational Biology and Department
of Structural Biology, University of Pittsburgh, Pittsburgh, Pennsylvania 15261, United States
| | - Xiang-Qun Xie
- Department
of Pharmaceutical Sciences and Computational Chemical
Genomics Screening Center, School of Pharmacy, Computational Drug Abuse Research
Center, Drug Discovery Institute, and Department of Computational Biology and Department
of Structural Biology, University of Pittsburgh, Pittsburgh, Pennsylvania 15261, United States
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21
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Alqarni M, Myint KZ, Tong Q, Yang P, Bartlow P, Wang L, Feng R, Xie XQ. Examining the critical roles of human CB2 receptor residues Valine 3.32 (113) and Leucine 5.41 (192) in ligand recognition and downstream signaling activities. Biochem Biophys Res Commun 2014; 452:334-9. [PMID: 25148941 DOI: 10.1016/j.bbrc.2014.08.048] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/06/2014] [Accepted: 08/11/2014] [Indexed: 11/19/2022]
Abstract
We performed molecular modeling and docking to predict a putative binding pocket and associated ligand-receptor interactions for human cannabinoid receptor 2 (CB2). Our data showed that two hydrophobic residues came in close contact with three structurally distinct CB2 ligands: CP-55,940, SR144528 and XIE95-26. Site-directed mutagenesis experiments and subsequent functional assays implicated the roles of Valine residue at position 3.32 (V113) and Leucine residue at position 5.41 (L192) in the ligand binding function and downstream signaling activities of the CB2 receptor. Four different point mutations were introduced to the wild type CB2 receptor: V113E, V113L, L192S and L192A. Our results showed that mutation of Val113 with a Glutamic acid and Leu192 with a Serine led to the complete loss of CB2 ligand binding as well as downstream signaling activities. Substitution of these residues with those that have similar hydrophobic side chains such as Leucine (V113L) and Alanine (L192A), however, allowed CB2 to retain both its ligand binding and signaling functions. Our modeling results validated by competition binding and site-directed mutagenesis experiments suggest that residues V113 and L192 play important roles in ligand binding and downstream signaling transduction of the CB2 receptor.
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Affiliation(s)
- Mohammed Alqarni
- Department of Pharmaceutical Sciences and Computational Chemical Genomics Screening Center, School of Pharmacy, Pittsburgh, PA 15260, USA
| | - Kyaw Zeyar Myint
- Department of Pharmaceutical Sciences and Computational Chemical Genomics Screening Center, School of Pharmacy, Pittsburgh, PA 15260, USA; Joint Carnegie Mellon University-University of Pittsburgh Ph.D. Program, Department of Computational Biology and Structural Biology, School of Medicine, Pittsburgh, PA 15260, USA
| | - Qin Tong
- Department of Pharmaceutical Sciences and Computational Chemical Genomics Screening Center, School of Pharmacy, Pittsburgh, PA 15260, USA
| | - Peng Yang
- Department of Pharmaceutical Sciences and Computational Chemical Genomics Screening Center, School of Pharmacy, Pittsburgh, PA 15260, USA
| | - Patrick Bartlow
- Department of Pharmaceutical Sciences and Computational Chemical Genomics Screening Center, School of Pharmacy, Pittsburgh, PA 15260, USA
| | - Lirong Wang
- Department of Pharmaceutical Sciences and Computational Chemical Genomics Screening Center, School of Pharmacy, Pittsburgh, PA 15260, USA
| | - Rentian Feng
- Department of Pharmaceutical Sciences and Computational Chemical Genomics Screening Center, School of Pharmacy, Pittsburgh, PA 15260, USA
| | - Xiang-Qun Xie
- Department of Pharmaceutical Sciences and Computational Chemical Genomics Screening Center, School of Pharmacy, Pittsburgh, PA 15260, USA; Joint Carnegie Mellon University-University of Pittsburgh Ph.D. Program, Department of Computational Biology and Structural Biology, School of Medicine, Pittsburgh, PA 15260, USA; Drug Discovery Institute, University of Pittsburgh, Pittsburgh, PA 15260, USA.
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22
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Gao M, Xu J, Wang M, Zheng QH. Facile and high-yield synthesis of N-(4-diethylamino)benzyl-4-[¹¹C]methoxy-N-(p-tolyl)benzenesulfonamide as a new potential PET selective CB2 radioligand. Appl Radiat Isot 2014; 90:181-6. [PMID: 24768996 DOI: 10.1016/j.apradiso.2014.03.029] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/21/2014] [Revised: 03/11/2014] [Accepted: 03/30/2014] [Indexed: 11/20/2022]
Abstract
The reference standard N-(4-diethylamino)benzyl-4-methoxy-N-(p-tolyl)benzenesulfonamide (3c) (CB2, Ki=0.5 nM; CB1, Ki=1297 nM; selectivity CB1/CB2=2594) and its corresponding precursor N-(4-diethylamino)benzyl-4-hydroxy-N-(p-tolyl)benzenesulfonamide (3d) were synthesized from 4-(diethylamino)benzaldehyde and p-toluidine in 3 steps with 75-84% overall chemical yield. The target tracer N-(4-diethylamino)benzyl-4-[(11)C]methoxy-N-(p-tolyl)benzenesulfonamide ([(11)C]3c) was synthesized from the phenol hydroxyl precursor by O-[(11)C]-methylation with [(11)C]CH3OTf, followed by HPLC combined with SPE purification in 40-50% decay corrected radiochemical yields with 370-740 GBq/μmol specific activity at the end of bombardment (EOB).
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Affiliation(s)
- Mingzhang Gao
- Department of Radiology and Imaging Sciences, Indiana University School of Medicine, 1345 West 16th Street, L3-202, Indianapolis, IN 46202-2111, USA
| | - Julie Xu
- Department of Radiology and Imaging Sciences, Indiana University School of Medicine, 1345 West 16th Street, L3-202, Indianapolis, IN 46202-2111, USA
| | - Min Wang
- Department of Radiology and Imaging Sciences, Indiana University School of Medicine, 1345 West 16th Street, L3-202, Indianapolis, IN 46202-2111, USA
| | - Qi-Huang Zheng
- Department of Radiology and Imaging Sciences, Indiana University School of Medicine, 1345 West 16th Street, L3-202, Indianapolis, IN 46202-2111, USA.
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23
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Wu Z, Shao P, Zhang S, Bai M. Targeted zwitterionic near infrared fluorescent probe for improved imaging of type 2 cannabinoid receptors. J Biomed Opt 2014; 19:36006. [PMID: 24604536 PMCID: PMC4019425 DOI: 10.1117/1.jbo.19.3.036006] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/30/2013] [Accepted: 01/30/2014] [Indexed: 05/05/2023]
Abstract
Recent studies indicate that the type 2 cannabinoid receptors (CB2R) have become an attractive target for treating a variety of pathologies, including cancers, neurodegenerative diseases, inflammation, pain, osteoporosis, immunological disorders and drug abuse. In addition, it appears that many of these diseases have up-regulated CB2R expression. However, the precise role of CB2R in the regulation of diseases remains unclear. The ability to specifically image CB2R would contribute to develop reliable CB2R-based therapeutic approaches with a better understanding of the mechanism of CB2R action in these diseases. We developed a CB2R-targeted zwitterionic near-infrared (NIR) fluorescent probe, ZW760-mbc94. When compared with a previously reported CB2R probe (NIR760-mbc94) with the same targeting moiety but a charged NIR fluorescent dye, ZW760-mbc94 showed improved binding specificity in vitro and ex vivo. Overall, ZW760-mbc94 appears to have great potential as a CB2R-targeted contrast agent.
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Affiliation(s)
- Zhiyuan Wu
- University of Pittsburgh, Department of Radiology, Molecular Imaging Laboratory, Pittsburgh, Pennsylvania 15219
- Shanghai Jiao Tong University, School of Medicine, Ruijin Hospital, Department of Radiology, Shanghai 200025, China
| | - Pin Shao
- University of Pittsburgh, Department of Radiology, Molecular Imaging Laboratory, Pittsburgh, Pennsylvania 15219
| | - Shaojuan Zhang
- University of Pittsburgh, Department of Radiology, Molecular Imaging Laboratory, Pittsburgh, Pennsylvania 15219
- Xi’an Jiaotong University, the First Hospital of Medical School, Department of Diagnostic Radiology, Xi’an, Shaanxi 710061, China
| | - Mingfeng Bai
- University of Pittsburgh, Department of Radiology, Molecular Imaging Laboratory, Pittsburgh, Pennsylvania 15219
- University of Pittsburgh Cancer Institute, Pittsburgh, Pennsylvania 15232
- Address all correspondence to: Mingfeng Bai, E-mail:
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24
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Abstract
Tandem affinity purification has been increasingly applied to isolation of recombinant proteins. It relies on two consecutive chromatographic steps that take advantage of the affinity tags placed at opposing ends of the target protein. This allows for efficient removal of contaminating proteins, including products of proteolytic degradation of the fusion that lack either N- or C-terminal tags. Here, we describe the use of two small affinity tags, a poly-histidine tag and a Strep-tag for expression and purification of the human cannabinoid receptor CB2, an integral membrane G protein-coupled receptor.
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Affiliation(s)
- Silvia C Locatelli-Hoops
- Laboratory of Membrane Biochemistry and Biophysics, National Institute on Alcohol Abuse and Alcoholism, National Institutes of Health, 5625 Fishers Lane, Bethesda, MD, 20892, USA
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25
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Kotsikorou E, Navas F, Roche MJ, Gilliam AF, Thomas B, Seltzman HH, Kumar P, Song ZH, Hurst DP, Lynch DL, Reggio PH. The importance of hydrogen bonding and aromatic stacking to the affinity and efficacy of cannabinoid receptor CB2 antagonist, 5-(4-chloro-3-methylphenyl)-1-[(4-methylphenyl)methyl]-N-[(1S,2S,4R)-1,3,3-trimethylbicyclo[2.2.1]hept-2-yl]-1H-pyrazole-3-carboxamide (SR144528). J Med Chem 2013; 56:6593-612. [PMID: 23855811 PMCID: PMC3804063 DOI: 10.1021/jm400070u] [Citation(s) in RCA: 17] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/11/2022]
Abstract
Despite the therapeutic promise of the subnanomolar affinity cannabinoid CB2 antagonist, 5-(4-chloro-3-methylphenyl)-1-[(4-methylphenyl)methyl]-N-[(1S,2S,4R)-1,3,3-trimethylbicyclo[2.2.1]hept-2-yl]-1H-pyrazole-3-carboxamide (SR144528, 1), little is known about its binding site interactions and no primary interaction site for 1 at CB2 has been identified. We report here the results of Glide docking studies in our cannabinoid CB2 inactive state model that were then tested via compound synthesis, binding, and functional assays. Our results show that the amide functional group of 1 is critical to its CB2 affinity and efficacy and that aromatic stacking interactions in the TMH5/6 aromatic cluster of CB2 are also important. Molecular modifications that increased the positive electrostatic potential in the region between the fenchyl and aromatic rings led to more efficacious compounds. This result is consistent with the EC-3 loop negatively charged amino acid, D275 (identified via Glide docking studies) acting as the primary interaction site for 1 and its analogues.
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Affiliation(s)
| | - Frank Navas
- Research Triangle Institute, Research Triangle Park, NC 27609
| | | | - Anne F. Gilliam
- Research Triangle Institute, Research Triangle Park, NC 27609
| | - Brian Thomas
- Research Triangle Institute, Research Triangle Park, NC 27609
| | | | - Pritesh Kumar
- Department of Pharmacology and Toxicology, University of Louisville, University of Louisville School of Medicine, Louisville, KY 40292
| | - Zhao-Hui Song
- Department of Pharmacology and Toxicology, University of Louisville, University of Louisville School of Medicine, Louisville, KY 40292
| | - Dow P. Hurst
- Center for Drug Discovery, Department of Chemistry and Biochemistry, University of North Carolina at Greensboro, Greensboro, NC 27402
| | - Diane L. Lynch
- Center for Drug Discovery, Department of Chemistry and Biochemistry, University of North Carolina at Greensboro, Greensboro, NC 27402
| | - Patricia H. Reggio
- Center for Drug Discovery, Department of Chemistry and Biochemistry, University of North Carolina at Greensboro, Greensboro, NC 27402
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26
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Chen JJ, Han S, Cao Y, Chen JZ. The agonist binding mechanism of human CB2 receptor studied by molecular dynamics simulation, free energy calculation and 3D-QSAR studies. Yao Xue Xue Bao 2013; 48:1436-1449. [PMID: 24358778] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 06/03/2023]
Abstract
CB2-selective agonists have drawn attention in drug discovery, since CB2 becomes a promising target for the treatment of neuropathic pain without psychoactive or other CNS-related side effects. However, the lack of experimental data of the 3D structures of human cannabinoid receptors hampers the understanding of the binding modes between ligands and CB2 by traditional methods. In the present work, combinational molecular modeling studies including flexible docking, MD simulations and free energy calculations were performed to investigate the interaction modes and mechanism of CB2-unselective agonist CP55940 and CB2-selective agonist GW842166X, separately binding with the homology model of CB2 in a DPPC/TIP3P simulated membrane environment. The binding free energies calculated by MM-PBSA method give an explanation for the activity differences of the studied ligands. Binding free energies decomposition by MM-GBSA method shows that the van der Waals interaction is the dominant driving force during the binding process. Our MD simulations demonstrate that Phe197 could be a critical residue for the binding of CB2-selective agonists. Furthermore, by using the MD simulated binding conformer as a template, the 3D-QSAR studies were performed with the comparative molecular field analysis (CoMFA) approach on a set of GW842166X analogues. A combinational exploration of both CoMFA steric and potential contour maps for CB2 affinities and the MD studied interaction modes sheds light on the structural requirements for CB2 agonists and serves as a basis for the design of novel CB2 agonists.
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Affiliation(s)
- Jiong-jiong Chen
- College of Pharmaceutical Sciences, Zhejiang University, Hangzhou 310058, China
| | - Shuang Han
- College of Pharmaceutical Sciences, Zhejiang University, Hangzhou 310058, China
| | - Yang Cao
- College of Pharmaceutical Sciences, Zhejiang University, Hangzhou 310058, China
| | - Jian-zhong Chen
- College of Pharmaceutical Sciences, Zhejiang University, Hangzhou 310058, China
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27
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Zheng C, Chen L, Chen X, He X, Yang J, Shi Y, Zhou N. The second intracellular loop of the human cannabinoid CB2 receptor governs G protein coupling in coordination with the carboxyl terminal domain. PLoS One 2013; 8:e63262. [PMID: 23667597 PMCID: PMC3646771 DOI: 10.1371/journal.pone.0063262] [Citation(s) in RCA: 19] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/02/2012] [Accepted: 04/01/2013] [Indexed: 11/18/2022] Open
Abstract
The major effects of cannabinoids and endocannabinoids are mediated via two G protein-coupled receptors, CB1 and CB2, elucidation of the mechanism and structural determinants of the CB2 receptor coupling with G proteins will have a significant impact on drug discovery. In the present study, we systematically investigated the role of the intracellular loops in the interaction of the CB2 receptor with G proteins using chimeric receptors alongside the characterization of cAMP accumulation and ERK1/2 phosphorylation. We provided evidence that ICL2 was significantly involved in G protein coupling in coordination with the C-terminal end. Moreover, a single alanine substitution of the Pro-139 in the CB2 receptor that corresponds to Leu-222 in the CB1 receptor resulted in a moderate impairment in the inhibition of cAMP accumulation, whereas mutants P139F, P139M and P139L were able to couple to the Gs protein in a CRE-driven luciferase assay. With the ERK activation experiments, we further found that P139L has the ability to activate ERK through both Gi- and Gs-mediated pathways. Our findings defined an essential role of the second intracellular loop of the CB2 receptor in coordination with the C-terminal tail in G protein coupling and receptor activation.
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MESH Headings
- Adenylyl Cyclase Inhibitors
- Adenylyl Cyclases/metabolism
- Amino Acid Sequence
- Cell Membrane/drug effects
- Cell Membrane/metabolism
- Cyclic AMP-Dependent Protein Kinases/antagonists & inhibitors
- Cyclic AMP-Dependent Protein Kinases/metabolism
- Enzyme Activation/drug effects
- Extracellular Signal-Regulated MAP Kinases/metabolism
- GTP-Binding Proteins/metabolism
- HEK293 Cells
- Humans
- Molecular Sequence Data
- Mutant Proteins/chemistry
- Mutant Proteins/metabolism
- Proline/metabolism
- Protein Binding/drug effects
- Protein Kinase Inhibitors/pharmacology
- Protein Structure, Secondary
- Protein Structure, Tertiary
- Receptor, Cannabinoid, CB1/chemistry
- Receptor, Cannabinoid, CB1/metabolism
- Receptor, Cannabinoid, CB2/agonists
- Receptor, Cannabinoid, CB2/chemistry
- Receptor, Cannabinoid, CB2/metabolism
- Recombinant Proteins/metabolism
- Signal Transduction/drug effects
- Structure-Activity Relationship
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Affiliation(s)
- Congxia Zheng
- Institute of Biochemistry, College of Life Sciences, Zhejiang University, Hangzhou, Zhejiang, China
- School of Art, Zhejiang International Studies University, Hangzhou, Zhejiang, China
| | - Linjie Chen
- Institute of Biochemistry, College of Life Sciences, Zhejiang University, Hangzhou, Zhejiang, China
| | - Xiaopan Chen
- Institute of Biochemistry, College of Life Sciences, Zhejiang University, Hangzhou, Zhejiang, China
| | - Xiaobai He
- Institute of Biochemistry, College of Life Sciences, Zhejiang University, Hangzhou, Zhejiang, China
| | - Jingwen Yang
- Institute of Sericulture and Apiculture, College of Animal Sciences, Zhejiang University, Hangzhou, Zhejiang, China
| | - Ying Shi
- Institute of Biochemistry, College of Life Sciences, Zhejiang University, Hangzhou, Zhejiang, China
| | - Naiming Zhou
- Institute of Biochemistry, College of Life Sciences, Zhejiang University, Hangzhou, Zhejiang, China
- * E-mail:
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28
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Kusakabe KI, Iso Y, Tada Y, Sakagami M, Morioka Y, Chomei N, Shinonome S, Kawamoto K, Takenaka H, Yasui K, Hamana H, Hanasaki K. Selective CB2 agonists with anti-pruritic activity: discovery of potent and orally available bicyclic 2-pyridones. Bioorg Med Chem 2013; 21:3154-63. [PMID: 23623258 DOI: 10.1016/j.bmc.2013.03.030] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/04/2013] [Revised: 03/15/2013] [Accepted: 03/16/2013] [Indexed: 01/24/2023]
Abstract
The CB2 receptor has emerged as a potential target for the treatment of pruritus as well as pain without CB1-mediated side effects. We previously identified 2-pyridone derivatives 1 and 2 as potent CB2 agonists; however, this series of compounds was found to have unacceptable pharmacokinetic profiles with no significant effect in vivo. To improve these profiles, we performed further structural optimization of 1 and 2, which led to the discovery of bicyclic 2-pyridone 18e with improved CB2 affinity and selectivity over CB1. In a mouse pruritus model, 18e inhibited compound 48/80 induced scratching behavior at a dose of 100 mg/kg. In addition, the docking model of 18e with an active-state CB2 homology model indicated the structural basis of its high affinity and selectivity over CB1.
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MESH Headings
- Administration, Oral
- Animals
- Antipruritics/chemical synthesis
- Antipruritics/pharmacokinetics
- Antipruritics/pharmacology
- Behavior, Animal/drug effects
- Bridged Bicyclo Compounds/chemical synthesis
- Bridged Bicyclo Compounds/pharmacokinetics
- Bridged Bicyclo Compounds/pharmacology
- CHO Cells
- Cricetulus
- Disease Models, Animal
- Drug Discovery
- Mice
- Mice, Inbred ICR
- Molecular Docking Simulation
- Pruritus/drug therapy
- Pruritus/metabolism
- Pruritus/physiopathology
- Pyridones/chemical synthesis
- Pyridones/pharmacokinetics
- Pyridones/pharmacology
- Receptor, Cannabinoid, CB1/chemistry
- Receptor, Cannabinoid, CB2/agonists
- Receptor, Cannabinoid, CB2/chemistry
- Receptor, Cannabinoid, CB2/metabolism
- Structure-Activity Relationship
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Affiliation(s)
- Ken-ichi Kusakabe
- Medicinal Research Laboratories, Shionogi Pharmaceutical Research Center, 11-1 Futaba-cho 3-chome, Toyonaka, Osaka 561-0825, Japan.
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29
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Abstract
In this manuscript, we have reported a novel 2D fingerprint-based artificial neural network QSAR (FANN-QSAR) method in order to effectively predict biological activities of structurally diverse chemical ligands. Three different types of fingerprints, namely, ECFP6, FP2 and MACCS, were used in FANN-QSAR algorithm development, and FANN-QSAR models were compared to known 3D and 2D QSAR methods using five data sets previously reported. In addition, the derived models were used to predict GPCR cannabinoid ligand binding affinities using our manually curated cannabinoid ligand database containing 1699 structurally diverse compounds with reported cannabinoid receptor subtype CB(2) activities. To demonstrate its useful applications, the established FANN-QSAR algorithm was used as a virtual screening tool to search a large NCI compound database for lead cannabinoid compounds, and we have discovered several compounds with good CB(2) binding affinities ranging from 6.70 nM to 3.75 μM. To the best of our knowledge, this is the first report for a fingerprint-based neural network approach validated with a successful virtual screening application in identifying lead compounds. The studies proved that the FANN-QSAR method is a useful approach to predict bioactivities or properties of ligands and to find novel lead compounds for drug discovery research.
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Affiliation(s)
- Kyaw-Zeyar Myint
- Department of Computational Biology, Joint Carnegie Mellon University-University of Pittsburgh Ph.D. Program, School of Medicine; Pittsburgh, Pennsylvania 15260
- Department of Pharmaceutical Sciences and Computational Chemical Genomics Screening Center, School of Pharmacy; Pittsburgh, Pennsylvania 15260
- Drug Discovery Institute; University of Pittsburgh, Pittsburgh, Pennsylvania 15260
| | - Lirong Wang
- Department of Pharmaceutical Sciences and Computational Chemical Genomics Screening Center, School of Pharmacy; Pittsburgh, Pennsylvania 15260
- Drug Discovery Institute; University of Pittsburgh, Pittsburgh, Pennsylvania 15260
- Pittsburgh Chemical Methods and Library Development (CMLD) Center; University of Pittsburgh, Pittsburgh, Pennsylvania 15260
| | - Qin Tong
- Department of Pharmaceutical Sciences and Computational Chemical Genomics Screening Center, School of Pharmacy; Pittsburgh, Pennsylvania 15260
| | - Xiang-Qun Xie
- Department of Computational Biology, Joint Carnegie Mellon University-University of Pittsburgh Ph.D. Program, School of Medicine; Pittsburgh, Pennsylvania 15260
- Department of Pharmaceutical Sciences and Computational Chemical Genomics Screening Center, School of Pharmacy; Pittsburgh, Pennsylvania 15260
- Drug Discovery Institute; University of Pittsburgh, Pittsburgh, Pennsylvania 15260
- Pittsburgh Chemical Methods and Library Development (CMLD) Center; University of Pittsburgh, Pittsburgh, Pennsylvania 15260
- Department of Structural Biology, University of Pittsburgh, Pittsburgh, Pennsylvania 15260
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30
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Kimura T, Yeliseev AA, Vukoti K, Rhodes SD, Cheng K, Rice KC, Gawrisch K. Recombinant cannabinoid type 2 receptor in liposome model activates g protein in response to anionic lipid constituents. J Biol Chem 2012; 287:4076-87. [PMID: 22134924 PMCID: PMC3281699 DOI: 10.1074/jbc.m111.268425] [Citation(s) in RCA: 35] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/04/2011] [Revised: 11/29/2011] [Indexed: 11/06/2022] Open
Abstract
Human cannabinoid type 2 (CB(2)) receptor expressed in Escherichia coli was purified and successfully reconstituted in the functional form into lipid bilayers composed of POPC, 1-palmitoyl-2-oleoyl-sn-glycero-3-phosphocholine, 1-palmitoyl-2-oleoyl-sn-glycero-3-phospho-L-serine (POPS), and cholesteryl hemisuccinate (CHS). Reconstitution was performed by detergent removal from the protein/lipid/detergent mixed micelles either on an adsorbent column, or by rapid dilution to below the critical micelle concentration of detergent followed by removal of detergent monomers on a concentrator. Proteoliposomes prepared at a protein/phospholipid/CHS molar ratio of 1/620-650/210-220 are free of detergent as shown by (1)H NMR, have a homogeneous protein/lipid ratio shown by isopycnic gradient ultracentrifugation, and are small in size with a mean diameter of 150-200 nm as measured by dynamic light scattering. Functional integrity of the reconstituted receptor was confirmed by quantitative binding of (2)H-labeled agonist CP-55,940-d(6) measured by (2)H magic angle spinning NMR, as well as by activation of G protein. The efficiency of G protein activation by agonist-bound CB(2) receptor was affected by negative electric surface potentials of proteoliposomes controlled by the content of anionic CHS or POPS. The activation was highest at an anionic lipid content of about 50 mol %. There was no correlation between the efficiency of G protein activation and an increase of hydrocarbon chain order induced by CHS or cholesterol. The results suggest the importance of anionic lipids in regulating signal transduction by CB(2) receptor and other class A GPCR. The successful reconstitution of milligram quantities of pure, functional CB(2) receptor enables a wide variety of structural studies.
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Affiliation(s)
- Tomohiro Kimura
- From the Laboratory of Membrane Biochemistry and Biophysics, NIAAA, and
| | | | - Krishna Vukoti
- From the Laboratory of Membrane Biochemistry and Biophysics, NIAAA, and
| | - Steven D. Rhodes
- From the Laboratory of Membrane Biochemistry and Biophysics, NIAAA, and
| | - Kejun Cheng
- the Chemical Biology Research Branch, NIDA and NIAAA, National Institutes of Health, Bethesda, Maryland 20852
| | - Kenner C. Rice
- the Chemical Biology Research Branch, NIDA and NIAAA, National Institutes of Health, Bethesda, Maryland 20852
| | - Klaus Gawrisch
- From the Laboratory of Membrane Biochemistry and Biophysics, NIAAA, and
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31
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Chen JZ, Myint KZ, Xie XQ. New QSAR prediction models derived from GPCR CB2-antagonistic triaryl bis-sulfone analogues by a combined molecular morphological and pharmacophoric approach. SAR QSAR Environ Res 2011; 22:525-544. [PMID: 21714749 DOI: 10.1080/1062936x.2011.569948] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/31/2023]
Abstract
In order to build quantitative structure-activity relationship (QSAR) models for virtual screening of novel cannabinoid CB2 ligands and hit ranking selections, a new QSAR algorithm has been developed for the cannabinoid ligands, triaryl bis-sulfones, using a combined molecular morphological and pharmacophoric search approach. Both pharmacophore features and shape complementarity were considered using a number of molecular descriptors, including Surflex-Sim similarity and Unity Query fit, in addition to other molecular properties such as molecular weight, ClogP, molecular volume, molecular area, molecular polar volume, molecular polar surface area and dipole moment. Subsequently, partial least squares regression analyses were carried out to derive QSAR models linking bioactivity and the descriptors mentioned, using a training set of 25 triaryl bis-sulfones. Good prediction capability was confirmed for the best QSAR model by evaluation against a test set of a further 20 triaryl bis-sulfones. The pharmacophore and molecular shape-based QSAR scoring function now established can be used to predict the biological properties of virtual hits or untested compounds obtained from ligand-based virtual screenings.
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Affiliation(s)
- J-Z Chen
- Department of Pharmaceutical Sciences, University of Pittsburgh, PA, USA
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32
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Moaddel R, Rosenberg A, Spelman K, Frazier J, Frazier C, Nocerino S, Brizzi A, Mugnaini C, Wainer IW. Development and characterization of immobilized cannabinoid receptor (CB1/CB2) open tubular column for on-line screening. Anal Biochem 2011; 412:85-91. [PMID: 21215722 PMCID: PMC3053438 DOI: 10.1016/j.ab.2010.12.034] [Citation(s) in RCA: 34] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/29/2010] [Revised: 12/20/2010] [Accepted: 12/28/2010] [Indexed: 01/23/2023]
Abstract
Cannabinoid receptors, CB1 and CB2, are therapeutic targets in the treatment of anxiety, obesity, movement disorders, glaucoma, and pain. We have developed an on-line screening method for CB1 and CB2 ligands, where cellular membrane fragments of a chronic myelogenous leukemia cell line, KU-812, were immobilized onto the surface of an open tubular (OT) capillary to create a CB1/CB2-OT column. The binding activities of the immobilized CB1/CB2 receptors were established using frontal affinity chromatographic techniques. This is the first report that confirms the presence of functional CB1 and CB2 receptors on KU-812 cells. The data from this study confirm that the CB1/CB2-OT column can be used to determine the binding affinities (K(i) values) for a single compound and to screen individual compounds or a mixture of multiple compounds. The CB1/CB2-OT column was also used to screen a botanical matrix, Zanthoxylum clava-herculis, where preliminary results suggest the presence of a high-affinity phytocannabinoid.
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MESH Headings
- Cannabinoids/chemistry
- Cell Line, Tumor
- Chromatography, Affinity/methods
- Humans
- Immobilized Proteins/chemistry
- Plant Roots/chemistry
- Protein Binding
- Receptor, Cannabinoid, CB1/agonists
- Receptor, Cannabinoid, CB1/chemistry
- Receptor, Cannabinoid, CB2/agonists
- Receptor, Cannabinoid, CB2/chemistry
- Zanthoxylum/chemistry
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Affiliation(s)
- R Moaddel
- Gerontology Research Center, National Institute on Aging, National Institutes of Health, Baltimore, MD 21224, USA.
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33
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Durdagi S, Kapou A, Kourouli T, Andreou T, Nikas SP, Nahmias VR, Papahatjis DP, Papadopoulos MG, Mavromoustakos T. The Application of 3D-QSAR Studies for Novel Cannabinoid Ligands Substituted at the C1‘ Position of the Alkyl Side Chain on the Structural Requirements for Binding to Cannabinoid Receptors CB1 and CB2. J Med Chem 2007; 50:2875-85. [PMID: 17521177 DOI: 10.1021/jm0610705] [Citation(s) in RCA: 41] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Abstract
A set of 30 novel Delta8-tetrahydrocannabinol and cannabidiol analogues were subjected to three-dimensional quantitative structure-activity relationship studies using the comparative molecular field analysis (CoMFA) and comparative molecular similarity indices analysis (CoMSIA) approaches. Using a combination of molecular modeling techniques and NMR spectroscopy, the putative bioactive conformation of the most potent cannabinoid (CB) ligand in the training set was determined. This conformer was used as the template and CB1 and CB2 pharmacophore models were developed. These models were fitted with experimental binding data and gave high correlation coefficients. Contour maps of the CB1 and CB2 models of CoMFA and CoMSIA approaches show that steric effects dominantly determine the binding affinities. The CoMFA and CoMSIA analyses based on the binding affinity data of CB ligands at the CB1 and CB2 receptors allowed us to deduce the possible optimal binding positions. This information can be used for the design of new CB analogues with enhanced activity and other tailored properties.
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Affiliation(s)
- Serdar Durdagi
- Institute of Organic and Pharmaceutical Chemistry, The National Hellenic Research Foundation, 48 Vas. Constantinou Avenue, 11635 Athens, Greece
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34
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Zhang R, Kim TK, Qiao ZH, Cai J, Pierce WM, Song ZH. Biochemical and mass spectrometric characterization of the human CB2 cannabinoid receptor expressed in Pichia pastoris--importance of correct processing of the N-terminus. Protein Expr Purif 2007; 55:225-35. [PMID: 17500008 DOI: 10.1016/j.pep.2007.03.018] [Citation(s) in RCA: 19] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/04/2006] [Revised: 03/13/2007] [Accepted: 03/13/2007] [Indexed: 10/23/2022]
Abstract
This study was conducted to optimize the expression of human CB2 cannabinoid receptors in methylotrophic yeast Pichia pastoris (P. pastoris). Two major species of expressed CB2 proteins were seen on Western blot, i.e., a 42 kDa band which matches the calculated molecular weight for tagged CB2, and a 52/55 kDa doublet. Treatment of membranes with N-glycosidase F or inclusion of tunicamycin in the culture medium during induction resulted in the disappearance of the 55 kDa, but not the 52 kDa band, suggesting that the 3 kDa extra in the 55 kDa band is due to N-glycosylation, but the 10 kDa extra in the 52 kDa band is not due to N-glycosylation. Anti-FLAG M1 antibody had a much higher preference for the 42 kDa band over the 52/55 kDa doublet, and a 10 kDa fragment recognized by anti-FLAG M2 antibody was generated by CNBr digestion of the 52/55 doublet. These data strongly support the hypothesis that the 10 kDa increase in molecular weight was due to unprocessed alpha-factor sequence. This conclusion was further validated by finding several peptide sequences for alpha-factor fragments at the N-terminal of the CB2 receptor using pepsin/chymotrypsin digestion and LC/MS/MS approaches. Importantly, unprocessed alpha-factor was found to be associated with poor ligand binding. In addition, controlling the level of CB2 protein expression was found to be critical for minimizing the presence of unprocessed alpha-factor sequence. The information gained from this study should aid the proper expression of not only CB2 receptor but also other members of the GPCR family in P. pastoris.
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Affiliation(s)
- Rundong Zhang
- Department of Pharmacology and Toxicology, University of Louisville School of Medicine, Louisville, KY 40292, USA
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35
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MESH Headings
- Humans
- Ligands
- Peptide Mapping
- Receptor, Cannabinoid, CB1/chemistry
- Receptor, Cannabinoid, CB1/metabolism
- Receptor, Cannabinoid, CB1/physiology
- Receptor, Cannabinoid, CB2/chemistry
- Receptor, Cannabinoid, CB2/metabolism
- Receptor, Cannabinoid, CB2/physiology
- Receptors, G-Protein-Coupled/chemistry
- Receptors, G-Protein-Coupled/metabolism
- Receptors, G-Protein-Coupled/physiology
- Sequence Homology, Amino Acid
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36
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Abstract
Since the discovery that Delta 9-tetrahydrocannabinol and related cannabinoids from Cannabis sativa L. act on specific physiological receptors in the human body and the subsequent elucidation of the mammalian endogenous cannabinoid system, no other natural product class has been reported to mimic the effects of cannabinoids. We recently found that N-alkyl amides from purple coneflower (Echinacea spp.) constitute a new class of cannabinomimetics, which specifically engage and activate the cannabinoid type-2 (CB2) receptors. Cannabinoid type-1 (CB1) and CB2 receptors belong to the family of G protein-coupled receptors and are the primary targets of the endogenous cannabinoids N-arachidonoyl ethanolamine and 2-arachidonoyl glyerol. CB2 receptors are believed to play an important role in distinct pathophysiological processes, including metabolic dysregulation, inflammation, pain, and bone loss. CB2 receptors have, therefore, become of interest as new targets in drug discovery. This review focuses on N-alkyl amide secondary metabolites from plants and underscores that this group of compounds may provide novel lead structures for the development of CB2-directed drugs.
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Affiliation(s)
- Jürg Gertsch
- Institute of Pharmaceutical Sciences, ETH Zurich, Zürich, Switzerland.
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37
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Yeliseev A, Zoubak L, Gawrisch K. Use of dual affinity tags for expression and purification of functional peripheral cannabinoid receptor. Protein Expr Purif 2006; 53:153-63. [PMID: 17223358 PMCID: PMC1906715 DOI: 10.1016/j.pep.2006.12.003] [Citation(s) in RCA: 42] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/25/2006] [Revised: 11/30/2006] [Accepted: 12/07/2006] [Indexed: 11/25/2022]
Abstract
The human peripheral cannabinoid receptor (CB2) was expressed as a fusion with the maltose-binding protein (at the N-terminus), thioredoxin A (at the C-terminus) and two small affinity tags (a Strep-tag and a polyhistidine tag). Expression levels of the recombinant receptor in Escherichia coli BL21(DE3) cells were dependent on location and type of tags in the expression construct, and were as high as 1-2mg per liter of bacterial culture. The recombinant receptor was ligand binding-competent, and activated cognate G-proteins in an in vitro coupled assay. The fusion CB2-125 protein was purified by immobilized metal affinity chromatography on a Ni-NTA resin. Maltose-binding protein, thioredoxin and a decahistidine tag were removed from the fusion by treatment with Tobacco etch virus (Tev) protease. Purification to over 90% homogeneity of the resulting CB2, containing an N-terminal Strep-tag was achieved by affinity chromatography on a StrepTactin resin. Circular dichroism spectroscopy indicated an alpha-helical content of the purified recombinant protein of approximately 54%. The expression and purification protocol allows for production of large (milligram) quantities of functional peripheral cannabinoid receptor, suitable for subsequent structural characterization. Preliminary results of reconstitution experiments indicate that the CB2 has retained its ligand-binding properties.
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MESH Headings
- Affinity Labels/chemistry
- Affinity Labels/metabolism
- Binding Sites
- Binding, Competitive
- Carrier Proteins/metabolism
- Cell Membrane/metabolism
- Chromatography, Affinity
- Circular Dichroism
- Endopeptidases/metabolism
- Escherichia coli/genetics
- Escherichia coli Proteins/metabolism
- Gene Expression
- Histidine/chemistry
- Humans
- Hydrolysis
- Maltose-Binding Proteins
- Protein Binding
- Protein Structure, Secondary
- Receptor, Cannabinoid, CB2/chemistry
- Receptor, Cannabinoid, CB2/genetics
- Receptor, Cannabinoid, CB2/isolation & purification
- Receptor, Cannabinoid, CB2/metabolism
- Recombinant Fusion Proteins/chemistry
- Recombinant Fusion Proteins/isolation & purification
- Recombinant Fusion Proteins/metabolism
- Streptavidin/metabolism
- Thioredoxins/metabolism
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Affiliation(s)
- Alexei Yeliseev
- Laboratory of Membrane Biochemistry and Biophysics, National Institute on Alcohol Abuse and Alcoholism, National Institutes of Health, 5625 Fishers Lane, Bethesda, MD 20892, USA.
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38
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Matovic N, Matthias A, Gertsch J, Raduner S, Bone KM, Lehmann RP, Devoss JJ. Stereoselective synthesis, natural occurrence and CB(2) receptor binding affinities of alkylamides from herbal medicines such as Echinacea sp. Org Biomol Chem 2006; 5:169-74. [PMID: 17164922 DOI: 10.1039/b615487e] [Citation(s) in RCA: 27] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
Abstract
A divergent synthesis of (2E,4E,8E,10E)- and (2E,4E,8E,10Z)-N-isobutyldodeca-2,4,8,10-tetraenamides from pent-4-yn-1-ol allowed identification of the (2E,4E,8E,10Z)-isomer for the first time in Echinacea species. A short, stereoselective synthesis of the (2E,4E,8E,10Z)-isomer is also described which allowed further biological evaluation of this material, and the demonstration that this isomer does not occur in Spilanthes mauritiana as previously reported.
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Affiliation(s)
- N Matovic
- Chemistry, School of Molecular and Microbial Sciences, The University of Queensland, Brisbane, 4072, Australia
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39
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Rodriguez-Martin I, Herrero-Turrion MJ, Marron Fdez de Velasco E, Gonzalez-Sarmiento R, Rodriguez RE. Characterization of two duplicate zebrafish Cb2-like cannabinoid receptors. Gene 2006; 389:36-44. [PMID: 17126498 DOI: 10.1016/j.gene.2006.09.016] [Citation(s) in RCA: 35] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/05/2006] [Revised: 09/04/2006] [Accepted: 09/13/2006] [Indexed: 11/29/2022]
Abstract
Several cannabinoid receptors have been detected in many organisms. The best known are CB1, mainly expressed in the central nervous system and CB2 which is almost exclusively expressed in the periphery. Here we report the molecular characterization of two duplicate CB2-like cannabinoid receptors from zebrafish (Danio rerio) (zebrafish Cb2a and zebrafish Cb2b). The amino acid sequences of these receptors present 56% identity with Takifugu rubripes CB2 sequence and 39% with human CB2 sequence and conserve some specific key residues for cannabinoid receptor function. Both duplicate receptors are expressed in peripheral tissues (gills, heart, intestine and muscle), immune tissue (spleen) and also in the central nervous system. Using in situ hybridization techniques zebrafish Cb2 mRNA expression was observed for the first time in the adenohypophysial cells of the rostral pars distalis and proximal pars distalis of the pituitary gland. Given the importance of the existence of duplication of genes in teleosts, the combined analysis of these two new cannabinoid receptors opens a new exciting door to investigate and understand cannabinoid function throughout evolution.
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MESH Headings
- Amino Acid Sequence
- Animals
- Base Sequence
- Brain/cytology
- Chromosomes
- Female
- Gene Expression Profiling
- Gene Expression Regulation
- Genes, Duplicate/genetics
- Genome
- Humans
- In Situ Hybridization
- Male
- Molecular Sequence Data
- Phylogeny
- RNA, Messenger/genetics
- RNA, Messenger/metabolism
- Receptor, Cannabinoid, CB2/chemistry
- Receptor, Cannabinoid, CB2/genetics
- Receptor, Cannabinoid, CB2/metabolism
- Receptors, Cannabinoid/chemistry
- Receptors, Cannabinoid/genetics
- Receptors, Cannabinoid/metabolism
- Zebrafish/genetics
- Zebrafish Proteins/chemistry
- Zebrafish Proteins/genetics
- Zebrafish Proteins/metabolism
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Affiliation(s)
- I Rodriguez-Martin
- Faculty of Medicine, Department of Biochemistry and Molecular Biology, University of Salamanca, Spain; Instituto de Neurociencias de Castilla y Leon (INCYL), Spain
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40
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Nebane NM, Kellie B, Song ZH. The effects of charge-neutralizing mutation D6.30N on the functions of CB1 and CB2 cannabinoid receptors. FEBS Lett 2006; 580:5392-8. [PMID: 16989818 DOI: 10.1016/j.febslet.2006.09.001] [Citation(s) in RCA: 13] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/05/2006] [Revised: 08/30/2006] [Accepted: 09/01/2006] [Indexed: 11/26/2022]
Abstract
Charge-neutralizing mutation D6.30N of the human cannabinoid receptor subtype 1 (CB1) and cannabinoid receptor subtype 2 (CB2) cannabinoid receptors was made to test two hypotheses: (1) D6.30 may be crucial for the functions of CB1 and CB2 receptors. (2) D6.30 may participate in an ionic lock with R3.50 that keeps the receptors in an inactive conformation. Specific ligand binding and ligand-induced inhibition of forskolin-stimulated cAMP accumulation were observed with human embryonic kidney epithelial cell line (HEK293) cells expressing wild-type CB1 and CB2, as well as CB1D6.30N and CB2D6.30N mutant receptors. There was however a decrease in maximum response of the mutant receptors compared to their wild-type counterparts, suggesting that D6.30 is essential for full activation of both CB1 and CB2 receptors. Both CB1D6.30N and CB2D6.30N demonstrated a level of constitutive activity no greater than that of their wild-type counterparts, indicating that either D6.30 does not participate in a salt bridge with R3.50, or the salt bridge is not critical for keeping cannabinoid receptors in the inactive conformation.
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MESH Headings
- Amino Acid Substitution
- Cell Line
- Colforsin/metabolism
- Colforsin/pharmacology
- Cyclic AMP/metabolism
- Humans
- Ligands
- Mutation, Missense
- Protein Binding/genetics
- Protein Structure, Secondary/genetics
- Receptor, Cannabinoid, CB1/chemistry
- Receptor, Cannabinoid, CB1/genetics
- Receptor, Cannabinoid, CB1/metabolism
- Receptor, Cannabinoid, CB2/chemistry
- Receptor, Cannabinoid, CB2/genetics
- Receptor, Cannabinoid, CB2/metabolism
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Affiliation(s)
- Ntsang M Nebane
- Department of Pharmacology and Toxicology, School of Medicine University of Louisville, KY 40292, USA
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41
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Abstract
The expression of membrane proteins has been the bottleneck for their structural studies. Recently, we developed a method to obtain milligram quantities of isotope-labeled seven transmembrane G-protein coupled cannabinoid (CB) receptor fragment in E. coli. In order to verify this method and confirm the recombinant isotope-labeled CB2 fragment, 3D hetero-nuclear NMR techniques were used to analyze the structure of the fragment CB2(180-233) in DMSO-d6 solvent. The sequential assignments of TM5 and intra-cellular loop 3 were accomplished, which confirmed the experimental protocols of isotope-labeled recombinant protein expression, fusion protein cleavage, and membrane protein purification. The obtained structure also showed alpha-helix in the TM5 region, but it was interrupted by a disordered region (Gly204_ILe206). These results further revealed that our established approach is a promising method to express recombinant membrane proteins for their structural studies.
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Affiliation(s)
- J Zhao
- Department of Pharmaceutical and Pharmacological Sciences, College of Pharmacy, University of Houston, TX 77204-5037, USA
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42
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Saario SM, Poso A, Juvonen RO, Järvinen T, Salo-Ahen OMH. Fatty Acid Amide Hydrolase Inhibitors from Virtual Screening of the Endocannabinoid System. J Med Chem 2006; 49:4650-6. [PMID: 16854070 DOI: 10.1021/jm060394q] [Citation(s) in RCA: 52] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Abstract
The endocannabinoid system consists of two cannabinoid receptors (CB1 and CB2), endogenous ligands (endocannabinoids), and the enzymes involved in the metabolism of the endocannabinoids, including fatty acid amide hydrolase (FAAH) and monoglyceride lipase (MGL). In the present study, virtual screening of MGL inhibitors was performed by utilizing a comparative model of the human MGL enzyme. All hit molecules were tested for their potential MGL inhibitory activity, but no compounds were found capable of inhibiting MGL-like enzymatic activity in rat cerebellar membranes. However, these compounds were also tested for their potential FAAH inhibitory activity and five compounds (2-6) inhibiting FAAH were found with IC50 values between 4 and 44 microM. In addition, the hit molecules from the virtual screening of CB2 receptor ligands (reported previously in Salo et al. J. Med. Chem. 2005, 48, 7166) were also tested in our FAAH assay, and four active compounds (7-10) were found with IC50 values between 0.52 and 22 microM. Additionally, compound 7 inhibited MGL-like enzymatic activity with an IC50 value of 31 microM.
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Affiliation(s)
- Susanna M Saario
- Department of Pharmaceutical Chemistry, University of Kuopio, P.O. Box 1627, FIN-70211 Kuopio, Finland.
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43
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Tuccinardi T, Ferrarini PL, Manera C, Ortore G, Saccomanni G, Martinelli A. Cannabinoid CB2/CB1 selectivity. Receptor modeling and automated docking analysis. J Med Chem 2006; 49:984-94. [PMID: 16451064 DOI: 10.1021/jm050875u] [Citation(s) in RCA: 68] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Abstract
Three-dimensional models of the CB1 and CB2 cannabinoid receptors were constructed by means of a molecular modeling procedure, using the X-ray structure of bovine rhodopsin as the initial template, and taking into account the available site-directed mutagenesis data. The cannabinoid system was studied by means of docking techniques. An analysis of the interaction of WIN55212-2 with both receptors showed that CB2/CB1 selectivity is mainly determined by the interaction in the CB2 with the nonconserved residues S3.31 and F5.46, whose importance was suggested by site-directed mutagenesis data. We also carried out an automated docking of several ligands into the CB2 model, using the AUTODOCK 3.0 program; the good correlation obtained between the estimated free energy binding and the experimental binding data confirmed our binding hypothesis and the reliability of the model.
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Affiliation(s)
- Tiziano Tuccinardi
- Dipartimento di Scienze Farmaceutiche, Università di Pisa, via Bonanno 6, 56126 Pisa, Italy
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44
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Raduner S, Majewska A, Chen JZ, Xie XQ, Hamon J, Faller B, Altmann KH, Gertsch J. Alkylamides from Echinacea are a new class of cannabinomimetics. Cannabinoid type 2 receptor-dependent and -independent immunomodulatory effects. J Biol Chem 2006; 281:14192-206. [PMID: 16547349 DOI: 10.1074/jbc.m601074200] [Citation(s) in RCA: 183] [Impact Index Per Article: 10.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022] Open
Abstract
Alkylamides (alkamides) from Echinacea modulate tumor necrosis factor alpha mRNA expression in human monocytes/macrophages via the cannabinoid type 2 (CB2) receptor (Gertsch, J., Schoop, R., Kuenzle, U., and Suter, A. (2004) FEBS Lett. 577, 563-569). Here we show that the alkylamides dodeca-2E,4E,8Z,10Z-tetraenoic acid isobutylamide (A1) and dodeca-2E,4E-dienoic acid isobutylamide (A2) bind to the CB2 receptor more strongly than the endogenous cannabinoids. The Ki values of A1 and A2 (CB2 approximately 60 nM; CB1 >1500 nM) were determined by displacement of the synthetic high affinity cannabinoid ligand [3H]CP-55,940. Molecular modeling suggests that alkylamides bind in the solvent-accessible cavity in CB2, directed by H-bonding and pi-pi interactions. In a screen with 49 other pharmacologically relevant receptors, it could be shown that A1 and A2 specifically bind to CB2 and CB1. A1 and A2 elevated total intracellular Ca2+ in CB2-positive but not in CB2-negative promyelocytic HL60 cells, an effect that was inhibited by the CB2 antagonist SR144528. At 50 nM, A1, A2, and the endogenous cannabinoid anandamide (CB2 Ki >200 nM) up-regulated constitutive interleukin (IL)-6 expression in human whole blood in a seemingly CB2-dependent manner. A1, A2, anandamide, the CB2 antagonist SR144528 (Ki <10 nM), and also the non-CB2-binding alkylamide undeca-2E-ene,8,10-diynoic acid isobutylamide all significantly inhibited lipopolysaccharide-induced tumor necrosis factor alpha, IL-1beta, and IL-12p70 expression (5-500 nM) in a CB2-independent manner. Alkylamides and anandamide also showed weak differential effects on anti-CD3-versus anti-CD28-stimulated cytokine expression in human whole blood. Overall, alkylamides, anandamide, and SR144528 potently inhibited lipopolysaccharide-induced inflammation in human whole blood and exerted modulatory effects on cytokine expression, but these effects are not exclusively related to CB2 binding.
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Affiliation(s)
- Stefan Raduner
- Department of Chemistry and Applied Biosciences, ETH Zurich, Wolfgang-Pauli-Strasse 10, CH-8093 Zürich, Switzerland
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45
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Gong JP, Onaivi ES, Ishiguro H, Liu QR, Tagliaferro PA, Brusco A, Uhl GR. Cannabinoid CB2 receptors: immunohistochemical localization in rat brain. Brain Res 2006; 1071:10-23. [PMID: 16472786 DOI: 10.1016/j.brainres.2005.11.035] [Citation(s) in RCA: 567] [Impact Index Per Article: 31.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/21/2005] [Revised: 10/21/2005] [Accepted: 11/02/2005] [Indexed: 11/25/2022]
Abstract
Brain expression of CB2 cannabinoid receptors has been much less well established and characterized in comparison to the expression of brain CB1 receptors. Since CB2 receptors are intensely expressed in peripheral and immune tissues, expression in brain microglia has been anticipated. Nevertheless, we now describe expression of CB2-receptor-like immunoreactivity in brain in neuronal patterns that support broader CNS roles for this receptor. Two anti-CB2 affinity purified polyclonal antibodies were raised in rabbits immunized with peptide conjugates that corresponded to amino acids 1-33 and 20-33. Western blot analyses revealed specific bands that were identified using these sera and were absent when the sera were preadsorbed with 8.3 mug/ml of the immunizing peptides. These studies, and initial RT-PCR analyses of brain CB1 and CB2 mRNAs, also support the expression of brain CB2 receptor transcripts at levels much lower than those of CB1 receptors. CB2 cannabinoid receptor mRNA was clearly expressed in the cerebellum of wild type but not in CB2 knockout mice. CB2 immunostaining was detected in the interpolar part of spinal 5th nucleus of wild type but not in CB2 knockout mice, using a mouse C-terminal CB2 receptor antibody. Immunohistochemical analyses revealed abundant immunostaining for CB2 receptors in apparent neuronal and glial processes in a number of rat brain areas. Cerebellar Purkinje cells and hippocampal pyramidal cells revealed substantial immunoreactivity that was absent when sections were stained with preadsorbed sera. CB2 immunoreactivity was also observed in olfactory tubercle, islands of Calleja, cerebral cortex, striatum, thalamic nuclei, hippocampus, amygdala, substantia nigra, periaqueductal gray, paratrochlear nucleus, paralemniscal nucleus, red nucleus, pontine nuclei, inferior colliculus and the parvocellular portion of the medial vestibular nucleus. In-vitro, CB2 immunoreactivity was also present in hippocampal cell cultures. The multifocal expression of CB2 immunoreactivity in glial and neuronal patterns in a number of brain regions suggests reevaluation of the possible roles that CB2 receptors may play in the brain.
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MESH Headings
- Animals
- Blotting, Northern/methods
- Blotting, Western/methods
- Brain/anatomy & histology
- Brain/metabolism
- Brain Mapping
- Cell Line
- Embryo, Mammalian
- Gene Expression/physiology
- Humans
- Immunohistochemistry
- In Situ Hybridization/methods
- In Vitro Techniques
- Mice
- Mice, Knockout
- RNA, Messenger/metabolism
- Rats
- Rats, Sprague-Dawley
- Receptor, Cannabinoid, CB2/chemistry
- Receptor, Cannabinoid, CB2/deficiency
- Receptor, Cannabinoid, CB2/genetics
- Receptor, Cannabinoid, CB2/metabolism
- Reverse Transcriptase Polymerase Chain Reaction/methods
- Transfection/methods
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Affiliation(s)
- Jian-Ping Gong
- Molecular Neurobiology Branch, Intramural Research Program, National Institute on Drug Abuse, NIH, Baltimore, MD 20892, USA
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46
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Murineddu G, Ruiu S, Loriga G, Manca I, Lazzari P, Reali R, Pani L, Toma L, Pinna GA. Tricyclic pyrazoles. 3. Synthesis, biological evaluation, and molecular modeling of analogues of the cannabinoid antagonist 8-chloro-1-(2',4'-dichlorophenyl)-N-piperidin-1-yl-1,4,5,6-tetrahydrobenzo[6,7]cyclohepta[1,2-c]pyrazole-3-carboxamide. J Med Chem 2006; 48:7351-62. [PMID: 16279795 DOI: 10.1021/jm050317f] [Citation(s) in RCA: 35] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Abstract
A series of analogues of 8-chloro-1-(2',4'-dichlorophenyl)-N-piperidin-1-yl-1,4,5,6-tetrahydrobenzo[6,7]cyclohepta[1,2-c]pyrazole-3-carboxamide 4a (NESS 0327) (Ruiu, S.; Pinna, G. A.; Marchese, G.; Mussinu, J. M.; Saba, P.; Tambaro, S.; Casti, P.; Vargiu, R.; Pani, L. Synthesis and Characterization of NESS 0327: A Novel Putative Antagonist of CB1 Cannabinoid Receptor. J. Pharmacol. Exp. Ther. 2003, 306, 363-370) was synthesized and evaluated for their affinity to cannabinoid receptors. Depending on the chemical modification of the lead structure that was chosen, compounds 4b, 4c, 4i, 4l, and 4m still proved to be potent binders of the CB1 receptor. Moreover, several analogues (4c, 4d, 4e, and 4m) demonstrated superior CB2 receptor binding affinities compared to the parent ligand. Compounds 4b, 4c, 4i, and 4l displayed the most promising pharmacological profiles, having the highest selectivity for CB1 receptors with Ki(CB2) to Ki(CB1) ratios of 11,250, 2000, 3330 and 4625, respectively. Compound 4c increased the intestinal propulsion in mice and antagonized the effect induced by the CB1 receptor agonist WIN 55,212-2. Finally, molecular modeling studies were carried out on a set of tricyclic pyrazoles (2a-4a) and on rimonabant 1 (SR141716A), indicating that high CB1 receptors affinities were consistent for the tricyclic derivatives, both with a nonplanar geometry of the tricyclic cores and with a precise orientation of the substituent (chlorine) on this ring system.
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MESH Headings
- Animals
- Binding, Competitive
- Brain/metabolism
- Gastrointestinal Transit/drug effects
- Heterocyclic Compounds, 3-Ring/chemical synthesis
- Heterocyclic Compounds, 3-Ring/chemistry
- Heterocyclic Compounds, 3-Ring/pharmacology
- In Vitro Techniques
- Mice
- Models, Molecular
- Piperidines/chemical synthesis
- Piperidines/chemistry
- Piperidines/pharmacology
- Pyrazoles/chemical synthesis
- Pyrazoles/chemistry
- Pyrazoles/pharmacology
- Radioligand Assay
- Receptor, Cannabinoid, CB1/antagonists & inhibitors
- Receptor, Cannabinoid, CB1/chemistry
- Receptor, Cannabinoid, CB2/antagonists & inhibitors
- Receptor, Cannabinoid, CB2/chemistry
- Stereoisomerism
- Structure-Activity Relationship
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Affiliation(s)
- Gabriele Murineddu
- Dipartimento Farmaco Chimico Tossicologico, Università di Sassari, Via F. Muroni 23/A, 07100 Sassari, Italy
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47
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Salo OMH, Raitio KH, Savinainen JR, Nevalainen T, Lahtela-Kakkonen M, Laitinen JT, Järvinen T, Poso A. Virtual screening of novel CB2 ligands using a comparative model of the human cannabinoid CB2 receptor. J Med Chem 2006; 48:7166-71. [PMID: 16279774 DOI: 10.1021/jm050565b] [Citation(s) in RCA: 45] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/12/2023]
Abstract
To identify novel selective CB2 lead compounds, a comparative model of the CB2 receptor was constructed using the high-resolution bovine rhodopsin X-ray structure as a template. The CB2 model was utilized both in building the database queries and in filtering the hit compounds by a docking and scoring method. In G-protein activation assays, 1-isoquinolyl[3-(trifluoromethyl)phenyl]methanone (40, NRB 04079) was found to act as a selective agonist at the human CB2 receptor.
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Affiliation(s)
- Outi M H Salo
- Department of Pharmaceutical Chemistry, University of Kuopio, P.O. Box 1627, FIN-70211 Kuopio, Finland.
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48
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Zheng H, Zhao J, Sheng W, Xie XQ. A transmembrane helix-bundle from G-protein coupled receptor CB2: Biosynthesis, purification, and NMR characterization. Biopolymers 2006; 83:46-61. [PMID: 16634087 DOI: 10.1002/bip.20526] [Citation(s) in RCA: 26] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/09/2022]
Abstract
The cannabinoid receptor subtype 2 (CB2) is a member of the G-protein coupled receptor (GPCR) superfamily. As the relationship between structure and function for this receptor remains poorly understood, the present study was undertaken to characterize the structure of a segment including the first and second transmembrane helix (TM1 and TM2) domains of CB2. To accomplish this, a transmembrane double-helix bundle from this region was expressed, purified, and characterized by NMR. Milligrams of this hydrophobic fragment of the receptor were biosynthesized using a fusion protein overexpression strategy and purified by affinity chromatography combined with reverse phase HPLC. Chemical and enzymatic cleavage methods were implemented to remove the fusion tag. The resultant recombinant protein samples were analyzed and confirmed by HPLC, mass spectrometry, and circular dichroism (CD). The CD analyses of HPLC-purified protein in solution and in DPC micelle preparations suggested predominant alpha-helical structures under both conditions. The 13C/15N double-labeled protein CB2(27-101) was further verified and analyzed by NMR spectroscopy. Sequential assignment was accomplished for more than 80% of residues. The 15N HSQC NMR results show a clear chemical shift dispersion of the amide nitrogen-proton correlation indicative of a pure double-labeled polypeptide molecule. The results suggest that this method is capable of generating transmembrane helical bundles from GPCRs in quantity and purity sufficient for NMR and other biophysical studies. Therefore, the biosynthesis of GPCR transmembrane helix bundles represents a satisfactory alternative strategy to obtain and assemble NMR structures from recombinant "building blocks."
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Affiliation(s)
- HaiAn Zheng
- Department of Pharmaceutical and Pharmacological Sciences, College of Pharmacy, University of Houston, Houston, TX, 77204-5037, USA
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49
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Chen JZ, Han XW, Liu Q, Makriyannis A, Wang J, Xie XQ. 3D-QSAR Studies of Arylpyrazole Antagonists of Cannabinoid Receptor Subtypes CB1 and CB2. A Combined NMR and CoMFA Approach. J Med Chem 2005; 49:625-36. [PMID: 16420048 DOI: 10.1021/jm050655g] [Citation(s) in RCA: 51] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Abstract
The present work focuses on the study of the three-dimensional (3D) structural requirements for selective antagonist activity of arylpyrazole compounds at the cannabinoid CB1 and CB2 receptors. Initially, a combined high-resolution two-dimensional (2D) NMR and computer modeling approach was carried out to study the solution structure of the key pyrazole derivative N-(piperidin-1-yl)-5-phenyl-1-(n-pentyl)-4-methyl-1H-pyrazole-3-carboxamide (AM263). By using the NMR-determined molecular conformers as templates, the 3D quantitative structure-activity relationship (QSAR) studies were performed with the comparative molecular field analysis (CoMFA) approach on a set of arylpyrazole cannabinoid receptor antagonists. Molecular alignments suitable for deriving valuable pharmacophoric features for this series of compounds were determined. Such systematic 3D-QSAR/CoMFA analyses of 29 molecules and their receptor affinities gave guidance for understanding the binding affinities of arylpyrazoles at the CB1 and CB2 binding sites, respectively. Comparison of CoMFA steric and potential contour maps for affinity at the two cannabinoid receptor subtypes helps to differentiate structural requirements for each subtype and serves as a basis for the design of later-generation analogues.
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Affiliation(s)
- Jian-Zhong Chen
- Department of Pharmaceutical & Pharmacological Sciences, College of Pharmacy, University of Houston, Texas 77204-5037, USA
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50
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Abstract
To date, two cannabinoid receptors have been isolated by molecular cloning. The CB1 and CB2 cannabinoid receptors are members of the G protein-coupled receptor family. There is also evidence for additional cannabinoid receptor subtypes. The CB1 and CB2 receptors recognize endogenous and exogenous cannabinoid compounds, which fall into five structurally diverse classes. Mutagenesis and molecular modeling studies have identified several key amino acid residues involved in the selective recognition of these ligands. Numerous residues involved in receptor activation have been elucidated. Regions of the CB1 receptor mediating desensitization and internalization have also been discovered. The known genetic structures of the CB1 and CB2 receptors indicate polymorphisms and multiple exons that maybe involved in tissue and species-specific regulation of these genes. The cannabinoid receptors are regulated during chronic agonist exposure, and gene expression is altered in disease states. There is a complex molecular architecture of the cannabinoid receptors that allows a single receptor to recognize multiple classes of compounds and produce an array of distinct downstream effects.
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MESH Headings
- Amino Acid Sequence
- Animals
- Binding Sites
- Drug Tolerance
- Humans
- Molecular Sequence Data
- Polymorphism, Genetic
- Protein Conformation
- Receptor, Cannabinoid, CB1/chemistry
- Receptor, Cannabinoid, CB1/genetics
- Receptor, Cannabinoid, CB1/physiology
- Receptor, Cannabinoid, CB2/chemistry
- Receptor, Cannabinoid, CB2/genetics
- Receptor, Cannabinoid, CB2/physiology
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Affiliation(s)
- M E Abood
- Forbes Norris MDA/ALS Research, California Pacific Medical Center, 2351 Clay St 416, San Francisco, CA 94115, USA.
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