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Falkenstein M, Elek M, Stark H. Chemical Probes for Histamine Receptor Subtypes. Curr Top Behav Neurosci 2021; 59:29-76. [PMID: 34595743 DOI: 10.1007/7854_2021_254] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/19/2022]
Abstract
Ligands with different properties and different selectivity are highly needed for in vitro and in vivo studies on the (patho)physiological influence of the chemical mediator histamine and its receptor subtypes. A selection of well-described ligands for the different receptor subtypes and different studies is shown with a particular focus on affinity and selectivity. In addition, compounds with radioactive or fluorescence elements will be presented with their beneficial use for other species or different investigations.
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Affiliation(s)
- Markus Falkenstein
- Institute of Pharmaceutical and Medicinal Chemistry, Heinrich Heine University Düsseldorf, Duesseldorf, Germany
| | - Milica Elek
- Institute of Pharmaceutical and Medicinal Chemistry, Heinrich Heine University Düsseldorf, Duesseldorf, Germany
| | - Holger Stark
- Institute of Pharmaceutical and Medicinal Chemistry, Heinrich Heine University Düsseldorf, Duesseldorf, Germany.
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2
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Tropmann K, Bresinsky M, Forster L, Mönnich D, Buschauer A, Wittmann HJ, Hübner H, Gmeiner P, Pockes S, Strasser A. Abolishing Dopamine D 2long/D 3 Receptor Affinity of Subtype-Selective Carbamoylguanidine-Type Histamine H 2 Receptor Agonists. J Med Chem 2021; 64:8684-8709. [PMID: 34110814 DOI: 10.1021/acs.jmedchem.1c00692] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/31/2022]
Abstract
3-(2-Amino-4-methylthiazol-5-yl)propyl-substituted carbamoylguanidines are potent, subtype-selective histamine H2 receptor (H2R) agonists, but their applicability as pharmacological tools to elucidate the largely unknown H2R functions in the central nervous system (CNS) is compromised by their concomitant high affinity toward dopamine D2-like receptors (especially to the D3R). To improve the selectivity, a series of novel carbamoylguanidine-type ligands containing various heterocycles, spacers, and side residues were rationally designed, synthesized, and tested in binding and/or functional assays at H1-4 and D2long/3 receptors. This study revealed a couple of selective candidates (among others 31 and 47), and the most promising ones were screened at several off-target receptors, showing good selectivities. Docking studies suggest that the amino acid residues (3.28, 3.32, E2.49, E2.51, 5.42, and 7.35) are responsible for the different affinities at the H2- and D2long/3-receptors. These results provide a solid base for the exploration of the H2R functions in the brain in further studies.
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Affiliation(s)
- Katharina Tropmann
- Institute of Pharmacy, University of Regensburg, Universitätsstraße 31, D-93053 Regensburg, Germany
| | - Merlin Bresinsky
- Institute of Pharmacy, University of Regensburg, Universitätsstraße 31, D-93053 Regensburg, Germany
| | - Lisa Forster
- Institute of Pharmacy, University of Regensburg, Universitätsstraße 31, D-93053 Regensburg, Germany
| | - Denise Mönnich
- Institute of Pharmacy, University of Regensburg, Universitätsstraße 31, D-93053 Regensburg, Germany
| | - Armin Buschauer
- Institute of Pharmacy, University of Regensburg, Universitätsstraße 31, D-93053 Regensburg, Germany
| | - Hans-Joachim Wittmann
- Institute of Pharmacy, University of Regensburg, Universitätsstraße 31, D-93053 Regensburg, Germany
| | - Harald Hübner
- Department of Chemistry and Pharmacy, Medicinal Chemistry, Friedrich-Alexander-University of Erlangen-Nürnberg, 91058 Erlangen, Germany
| | - Peter Gmeiner
- Department of Chemistry and Pharmacy, Medicinal Chemistry, Friedrich-Alexander-University of Erlangen-Nürnberg, 91058 Erlangen, Germany
| | - Steffen Pockes
- Institute of Pharmacy, University of Regensburg, Universitätsstraße 31, D-93053 Regensburg, Germany.,Department of Neurology, University of Minnesota, Minneapolis, Minnesota 55455, United States.,Department of Medicinal Chemistry, Institute for Therapeutics Discovery and Development, University of Minnesota, Minneapolis, Minnesota 55414, United States
| | - Andrea Strasser
- Institute of Pharmacy, University of Regensburg, Universitätsstraße 31, D-93053 Regensburg, Germany
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Hattori Y, Seifert R. Pharmacological Characterization of Human Histamine Receptors and Histamine Receptor Mutants in the Sf9 Cell Expression System. Handb Exp Pharmacol 2017; 241:63-118. [PMID: 28233175 PMCID: PMC7120522 DOI: 10.1007/164_2016_124] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/12/2023]
Abstract
A large problem of histamine receptor research is data heterogeneity. Various experimental approaches, the complex signaling pathways of mammalian cells, and the use of different species orthologues render it difficult to compare and interpret the published results. Thus, the four human histamine receptor subtypes were analyzed side-by-side in the Sf9 insect cell expression system, using radioligand binding assays as well as functional readouts proximal to the receptor activation event (steady-state GTPase assays and [35S]GTPγS assays). The human H1R was co-expressed with the regulators of G protein signaling RGS4 or GAIP, which unmasked a productive interaction between hH1R and insect cell Gαq. By contrast, functional expression of the hH2R required the generation of an hH2R-Gsα fusion protein to ensure close proximity of G protein and receptor. Fusion of hH2R to the long (GsαL) or short (GsαS) splice variant of Gαs resulted in comparable constitutive hH2R activity, although both G protein variants show different GDP affinities. Medicinal chemistry studies revealed profound species differences between hH1R/hH2R and their guinea pig orthologues gpH1R/gpH2R. The causes for these differences were analyzed by molecular modeling in combination with mutational studies. Co-expression of the hH3R with Gαi1, Gαi2, Gαi3, and Gαi/o in Sf9 cells revealed high constitutive activity and comparable interaction efficiency with all G protein isoforms. A comparison of various cations (Li+, Na+, K+) and anions (Cl-, Br-, I-) revealed that anions with large radii most efficiently stabilize the inactive hH3R state. Potential sodium binding sites in the hH3R protein were analyzed by expressing specific hH3R mutants in Sf9 cells. In contrast to the hH3R, the hH4R preferentially couples to co-expressed Gαi2 in Sf9 cells. Its high constitutive activity is resistant to NaCl or GTPγS. The hH4R shows structural instability and adopts a G protein-independent high-affinity state. A detailed characterization of affinity and activity of a series of hH4R antagonists/inverse agonists allowed first conclusions about structure/activity relationships for inverse agonists at hH4R. In summary, the Sf9 cell system permitted a successful side-by-side comparison of all four human histamine receptor subtypes. This chapter summarizes the results of pharmacological as well as medicinal chemistry/molecular modeling approaches and demonstrates that these data are not only important for a deeper understanding of HxR pharmacology, but also have significant implications for the molecular pharmacology of GPCRs in general.
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Affiliation(s)
- Yuichi Hattori
- Department of Molecular and Medical Pharmacology, Graduate School of Medical and Pharmaceutical Sciences, University of Toyama, Toyama, Japan
| | - Roland Seifert
- Institute of Pharmacology, Medical School of Hannover, Hannover, Germany
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4
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Geyer R, Nordemann U, Strasser A, Wittmann HJ, Buschauer A. Conformational Restriction and Enantioseparation Increase Potency and Selectivity of Cyanoguanidine-Type Histamine H4 Receptor Agonists. J Med Chem 2016; 59:3452-70. [PMID: 27007611 DOI: 10.1021/acs.jmedchem.6b00120] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Abstract
2-Cyano-1-[4-(1H-imidazol-4-yl)butyl]-3-[2-(phenylsulfanyl)ethyl]guanidine (UR-PI376, 1) is a potent and selective agonist of the human histamine H4 receptor (hH4R). To gain information on the active conformation, we synthesized analogues of 1 with a cyclopentane-1,3-diyl linker. Affinities and functional activities were determined at recombinant hHxR (x: 1-4) subtypes on Sf9 cell membranes (radioligand binding, [(35)S]GTPγS, or GTPase assays) and in part in luciferase assays on human or mouse H4R (HEK-293 cells). The most potent H4R agonists among 14 racemates were separated by chiral HPLC, yielding eight enantiomerically pure compounds. Configurations were assigned based on X-ray structures of intermediates and a stereocontrolled synthetic pathway. (+)-2-Cyano-1-{[trans-(1S,3S)-3-(1H-imidazol-4-yl)cyclopentyl]methyl}-3-[2-(phenylsulfanyl)ethyl]guanidine ((1S,3S)-UR-RG98, 39a) was the most potent H4R agonist in this series (EC50 11 nM; H4R vs H3R, >100-fold selectivity; H1R, H2R, negligible activities), whereas the optical antipode proved to be an H4R antagonist ([(35)S]GTPγS assay). MD simulations confirmed differential stabilization of the active and inactive H4R state by the enantiomers.
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Affiliation(s)
- Roland Geyer
- Institute of Pharmacy, Pharmaceutical/Medicinal Chemistry, Faculty of Chemistry and Pharmacy, University of Regensburg , Universitätsstraße 31, D-93053 Regensburg, Germany
| | - Uwe Nordemann
- Institute of Pharmacy, Pharmaceutical/Medicinal Chemistry, Faculty of Chemistry and Pharmacy, University of Regensburg , Universitätsstraße 31, D-93053 Regensburg, Germany
| | - Andrea Strasser
- Institute of Pharmacy, Pharmaceutical/Medicinal Chemistry, Faculty of Chemistry and Pharmacy, University of Regensburg , Universitätsstraße 31, D-93053 Regensburg, Germany
| | - Hans-Joachim Wittmann
- Institute of Pharmacy, Pharmaceutical/Medicinal Chemistry, Faculty of Chemistry and Pharmacy, University of Regensburg , Universitätsstraße 31, D-93053 Regensburg, Germany
| | - Armin Buschauer
- Institute of Pharmacy, Pharmaceutical/Medicinal Chemistry, Faculty of Chemistry and Pharmacy, University of Regensburg , Universitätsstraße 31, D-93053 Regensburg, Germany
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5
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Panula P, Chazot PL, Cowart M, Gutzmer R, Leurs R, Liu WLS, Stark H, Thurmond RL, Haas HL. International Union of Basic and Clinical Pharmacology. XCVIII. Histamine Receptors. Pharmacol Rev 2016; 67:601-55. [PMID: 26084539 DOI: 10.1124/pr.114.010249] [Citation(s) in RCA: 362] [Impact Index Per Article: 45.3] [Reference Citation Analysis] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/21/2022] Open
Abstract
Histamine is a developmentally highly conserved autacoid found in most vertebrate tissues. Its physiological functions are mediated by four 7-transmembrane G protein-coupled receptors (H1R, H2R, H3R, H4R) that are all targets of pharmacological intervention. The receptors display molecular heterogeneity and constitutive activity. H1R antagonists are long known antiallergic and sedating drugs, whereas the H2R was identified in the 1970s and led to the development of H2R-antagonists that revolutionized stomach ulcer treatment. The crystal structure of ligand-bound H1R has rendered it possible to design new ligands with novel properties. The H3R is an autoreceptor and heteroreceptor providing negative feedback on histaminergic and inhibition on other neurons. A block of these actions promotes waking. The H4R occurs on immuncompetent cells and the development of anti-inflammatory drugs is anticipated.
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Affiliation(s)
- Pertti Panula
- Department of Anatomy, and Neuroscience Center, University of Helsinki, Finland (P.P.); School of Biological and Biomedical Sciences, University of Durham, United Kingdom (P.L.C.); AbbVie, Inc. North Chicago, Illinois (M.C.); Department of Dermatology and Allergy, Hannover Medical School, Hannover, Germany (R.G.); Department of Medicinal Chemistry, Amsterdam Institute of Molecules, Medicines and Systems, VU University Amsterdam, The Netherlands (R.L.); Ziarco Pharma Limited, Canterbury, United Kingdom (W.L.S.L.); Institute of Pharmaceutical and Medical Chemistry and Institute of Neurophysiology, Medical Faculty, Westfalische-Wilhelms-University, Muenster, Germany (H.L.H.); Heinrich-Heine-University Duesseldorf, Germany (H.S.); and Janssen Research & Development, LLC, San Diego, California (R.L.T.)
| | - Paul L Chazot
- Department of Anatomy, and Neuroscience Center, University of Helsinki, Finland (P.P.); School of Biological and Biomedical Sciences, University of Durham, United Kingdom (P.L.C.); AbbVie, Inc. North Chicago, Illinois (M.C.); Department of Dermatology and Allergy, Hannover Medical School, Hannover, Germany (R.G.); Department of Medicinal Chemistry, Amsterdam Institute of Molecules, Medicines and Systems, VU University Amsterdam, The Netherlands (R.L.); Ziarco Pharma Limited, Canterbury, United Kingdom (W.L.S.L.); Institute of Pharmaceutical and Medical Chemistry and Institute of Neurophysiology, Medical Faculty, Westfalische-Wilhelms-University, Muenster, Germany (H.L.H.); Heinrich-Heine-University Duesseldorf, Germany (H.S.); and Janssen Research & Development, LLC, San Diego, California (R.L.T.)
| | - Marlon Cowart
- Department of Anatomy, and Neuroscience Center, University of Helsinki, Finland (P.P.); School of Biological and Biomedical Sciences, University of Durham, United Kingdom (P.L.C.); AbbVie, Inc. North Chicago, Illinois (M.C.); Department of Dermatology and Allergy, Hannover Medical School, Hannover, Germany (R.G.); Department of Medicinal Chemistry, Amsterdam Institute of Molecules, Medicines and Systems, VU University Amsterdam, The Netherlands (R.L.); Ziarco Pharma Limited, Canterbury, United Kingdom (W.L.S.L.); Institute of Pharmaceutical and Medical Chemistry and Institute of Neurophysiology, Medical Faculty, Westfalische-Wilhelms-University, Muenster, Germany (H.L.H.); Heinrich-Heine-University Duesseldorf, Germany (H.S.); and Janssen Research & Development, LLC, San Diego, California (R.L.T.)
| | - Ralf Gutzmer
- Department of Anatomy, and Neuroscience Center, University of Helsinki, Finland (P.P.); School of Biological and Biomedical Sciences, University of Durham, United Kingdom (P.L.C.); AbbVie, Inc. North Chicago, Illinois (M.C.); Department of Dermatology and Allergy, Hannover Medical School, Hannover, Germany (R.G.); Department of Medicinal Chemistry, Amsterdam Institute of Molecules, Medicines and Systems, VU University Amsterdam, The Netherlands (R.L.); Ziarco Pharma Limited, Canterbury, United Kingdom (W.L.S.L.); Institute of Pharmaceutical and Medical Chemistry and Institute of Neurophysiology, Medical Faculty, Westfalische-Wilhelms-University, Muenster, Germany (H.L.H.); Heinrich-Heine-University Duesseldorf, Germany (H.S.); and Janssen Research & Development, LLC, San Diego, California (R.L.T.)
| | - Rob Leurs
- Department of Anatomy, and Neuroscience Center, University of Helsinki, Finland (P.P.); School of Biological and Biomedical Sciences, University of Durham, United Kingdom (P.L.C.); AbbVie, Inc. North Chicago, Illinois (M.C.); Department of Dermatology and Allergy, Hannover Medical School, Hannover, Germany (R.G.); Department of Medicinal Chemistry, Amsterdam Institute of Molecules, Medicines and Systems, VU University Amsterdam, The Netherlands (R.L.); Ziarco Pharma Limited, Canterbury, United Kingdom (W.L.S.L.); Institute of Pharmaceutical and Medical Chemistry and Institute of Neurophysiology, Medical Faculty, Westfalische-Wilhelms-University, Muenster, Germany (H.L.H.); Heinrich-Heine-University Duesseldorf, Germany (H.S.); and Janssen Research & Development, LLC, San Diego, California (R.L.T.)
| | - Wai L S Liu
- Department of Anatomy, and Neuroscience Center, University of Helsinki, Finland (P.P.); School of Biological and Biomedical Sciences, University of Durham, United Kingdom (P.L.C.); AbbVie, Inc. North Chicago, Illinois (M.C.); Department of Dermatology and Allergy, Hannover Medical School, Hannover, Germany (R.G.); Department of Medicinal Chemistry, Amsterdam Institute of Molecules, Medicines and Systems, VU University Amsterdam, The Netherlands (R.L.); Ziarco Pharma Limited, Canterbury, United Kingdom (W.L.S.L.); Institute of Pharmaceutical and Medical Chemistry and Institute of Neurophysiology, Medical Faculty, Westfalische-Wilhelms-University, Muenster, Germany (H.L.H.); Heinrich-Heine-University Duesseldorf, Germany (H.S.); and Janssen Research & Development, LLC, San Diego, California (R.L.T.)
| | - Holger Stark
- Department of Anatomy, and Neuroscience Center, University of Helsinki, Finland (P.P.); School of Biological and Biomedical Sciences, University of Durham, United Kingdom (P.L.C.); AbbVie, Inc. North Chicago, Illinois (M.C.); Department of Dermatology and Allergy, Hannover Medical School, Hannover, Germany (R.G.); Department of Medicinal Chemistry, Amsterdam Institute of Molecules, Medicines and Systems, VU University Amsterdam, The Netherlands (R.L.); Ziarco Pharma Limited, Canterbury, United Kingdom (W.L.S.L.); Institute of Pharmaceutical and Medical Chemistry and Institute of Neurophysiology, Medical Faculty, Westfalische-Wilhelms-University, Muenster, Germany (H.L.H.); Heinrich-Heine-University Duesseldorf, Germany (H.S.); and Janssen Research & Development, LLC, San Diego, California (R.L.T.)
| | - Robin L Thurmond
- Department of Anatomy, and Neuroscience Center, University of Helsinki, Finland (P.P.); School of Biological and Biomedical Sciences, University of Durham, United Kingdom (P.L.C.); AbbVie, Inc. North Chicago, Illinois (M.C.); Department of Dermatology and Allergy, Hannover Medical School, Hannover, Germany (R.G.); Department of Medicinal Chemistry, Amsterdam Institute of Molecules, Medicines and Systems, VU University Amsterdam, The Netherlands (R.L.); Ziarco Pharma Limited, Canterbury, United Kingdom (W.L.S.L.); Institute of Pharmaceutical and Medical Chemistry and Institute of Neurophysiology, Medical Faculty, Westfalische-Wilhelms-University, Muenster, Germany (H.L.H.); Heinrich-Heine-University Duesseldorf, Germany (H.S.); and Janssen Research & Development, LLC, San Diego, California (R.L.T.)
| | - Helmut L Haas
- Department of Anatomy, and Neuroscience Center, University of Helsinki, Finland (P.P.); School of Biological and Biomedical Sciences, University of Durham, United Kingdom (P.L.C.); AbbVie, Inc. North Chicago, Illinois (M.C.); Department of Dermatology and Allergy, Hannover Medical School, Hannover, Germany (R.G.); Department of Medicinal Chemistry, Amsterdam Institute of Molecules, Medicines and Systems, VU University Amsterdam, The Netherlands (R.L.); Ziarco Pharma Limited, Canterbury, United Kingdom (W.L.S.L.); Institute of Pharmaceutical and Medical Chemistry and Institute of Neurophysiology, Medical Faculty, Westfalische-Wilhelms-University, Muenster, Germany (H.L.H.); Heinrich-Heine-University Duesseldorf, Germany (H.S.); and Janssen Research & Development, LLC, San Diego, California (R.L.T.)
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6
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Dimeric carbamoylguanidine-type histamine H2 receptor ligands: A new class of potent and selective agonists. Bioorg Med Chem 2015; 23:3957-69. [PMID: 25639885 DOI: 10.1016/j.bmc.2015.01.012] [Citation(s) in RCA: 22] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/11/2014] [Revised: 12/21/2014] [Accepted: 01/07/2015] [Indexed: 11/23/2022]
Abstract
The bioisosteric replacement of the acylguanidine moieties in dimeric histamine H2 receptor (H2R) agonists by carbamoylguanidine groups resulted in compounds with retained potencies and intrinsic activities, but considerably improved stability against hydrolytic cleavage. These compounds achieved up to 2500 times the potency of histamine when studied in [(35)S]GTPγS assays on recombinant human and guinea pig H2R. Unlike 3-(imidazol-4-yl)propyl substituted carbamoylguanidines, the corresponding 2-amino-4-methylthiazoles revealed selectivity over histamine receptor subtypes H1R, H3R and H4R in radioligand competition binding studies. H2R binding studies with three fluorescent compounds and one tritium-labeled ligand, synthesized from a chain-branched precursor, failed due to pronounced cellular accumulation and high non-specific binding. However, the dimeric H2R agonists proved to be useful pharmacological tools for functional studies on native cells, as demonstrated for selected compounds by cAMP accumulation and inhibition of fMLP-stimulated generation of reactive oxygen species in human monocytes.
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Geyer R, Igel P, Kaske M, Elz S, Buschauer A. Synthesis, SAR and selectivity of 2-acyl- and 2-cyano-1-hetarylalkyl-guanidines at the four histamine receptor subtypes: a bioisosteric approach. MEDCHEMCOMM 2014. [DOI: 10.1039/c3md00245d] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
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8
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Seifert R. Functional selectivity of G-protein-coupled receptors: from recombinant systems to native human cells. Biochem Pharmacol 2013; 86:853-61. [PMID: 23933388 DOI: 10.1016/j.bcp.2013.07.029] [Citation(s) in RCA: 44] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/16/2013] [Revised: 07/25/2013] [Accepted: 07/25/2013] [Indexed: 10/26/2022]
Abstract
In the mid 1990s, it was assumed that a two-state model, postulating an inactive (R) state and an active (R*) state provides the molecular basis for GPCR activation. However, it became clear that this model could not accommodate many experimental observations. Accordingly, the two-state model was superseded by a multi-state model according to which any given ligand stabilizes a unique receptor conformation with distinct capabilities of activating down-stream G-proteins and β-arrestin. Much of this research was conducted with the β2-adrenoceptor in recombinant systems. At the molecular level, there is now no doubt anymore that ligand-specific receptor conformations, also referred to as functional selectivity, exist. This concept holds great potential for drug discovery in terms of developing drugs with higher selectivity for specific cells and/or cell functions and fewer side effects. A major challenge is the analysis for functional selectivity in native cells. Here, I discuss our current knowledge on functional selectivity of three representative GPCRs, the β2-adrenoceptor and the histamine H2- and H4-receptors, in recombinant systems and native human cells. Studies with human neutrophils and eosinophils support the concept of functional selectivity. A major strategy for the analysis of functional selectivity in native cells is to generate complete concentration/response curves with a large set of structurally diverse ligands for multiple parameters. Next, correlations of potencies and efficacies are analyzed, and deviations of the correlations from linearity are indicative for functional selectivity. Additionally, pharmacological inhibitors are used to dissect cell functions from each other.
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Affiliation(s)
- Roland Seifert
- Institute of Pharmacology, Medical School of Hannover, Carl-Neuberg-Str. 1, D-30625 Hannover, Germany.
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9
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Seifert R, Strasser A, Schneider EH, Neumann D, Dove S, Buschauer A. Molecular and cellular analysis of human histamine receptor subtypes. Trends Pharmacol Sci 2013; 34:33-58. [PMID: 23254267 PMCID: PMC3869951 DOI: 10.1016/j.tips.2012.11.001] [Citation(s) in RCA: 126] [Impact Index Per Article: 11.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/21/2012] [Revised: 11/03/2012] [Accepted: 11/05/2012] [Indexed: 01/08/2023]
Abstract
The human histamine receptors hH(1)R and hH(2)R constitute important drug targets, and hH(3)R and hH(4)R have substantial potential in this area. Considering the species-specificity of pharmacology of H(x)R orthologs, it is important to analyze hH(x)Rs. Here, we summarize current knowledge of hH(x)Rs endogenously expressed in human cells and hH(x)Rs recombinantly expressed in mammalian and insect cells. We present the advantages and disadvantages of the various systems. We also discuss problems associated with the use of hH(x)R antibodies, an issue of general relevance for G-protein-coupled receptors (GPCRs). There is much greater overlap in activity of 'selective' ligands for other hH(x)Rs than the cognate receptor subtype than generally appreciated. Studies with native and recombinant systems support the concept of ligand-specific receptor conformations, encompassing agonists and antagonists. It is emerging that for characterization of hH(x)R ligands, one cannot rely on a single test system and a single parameter. Rather, multiple systems and parameters have to be studied. Although such studies are time-consuming and expensive, ultimately, they will increase drug safety and efficacy.
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Affiliation(s)
- Roland Seifert
- Institute of Pharmacology, Medical School of Hannover, Hannover, Germany.
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10
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Strasser A, Wittmann HJ, Buschauer A, Schneider EH, Seifert R. Species-dependent activities of G-protein-coupled receptor ligands: lessons from histamine receptor orthologs. Trends Pharmacol Sci 2012; 34:13-32. [PMID: 23228711 DOI: 10.1016/j.tips.2012.10.004] [Citation(s) in RCA: 70] [Impact Index Per Article: 5.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/31/2012] [Revised: 10/26/2012] [Accepted: 10/31/2012] [Indexed: 12/26/2022]
Abstract
Histamine is a biogenic amine that exerts its biological effects as a neurotransmitter and local mediator via four histamine receptor (HR) subtypes (H(x)Rs) - H(1)R, H(2)R, H(3)R, and H(4)R - belonging to the superfamily of G-protein-coupled receptors (GPCRs). All four H(x)Rs exhibit pronounced differences in agonist and/or antagonist pharmacology among various species orthologs. The species differences constitute a problem for animal experiments and drug development. This problem applies to GPCRs with diverse ligands. Here, we summarize our current knowledge on H(x)R orthologs as a case study for species-dependent activity of GPCR ligands. We show that species-specific pharmacology also provides unique opportunities to study important aspects of GPCR pharmacology in general, including ligand-binding sites, the roles of extracellular domains in ligand binding and receptor activation, agonist-independent (constitutive) receptor activity, thermodynamics of ligand/receptor interaction, receptor-activation mechanisms, and ligand-specific receptor conformations.
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Affiliation(s)
- Andrea Strasser
- Department of Pharmaceutical/Medicinal Chemistry II, University of Regensburg, Regensburg, Germany.
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11
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Birnkammer T, Spickenreither A, Brunskole I, Lopuch M, Kagermeier N, Bernhardt G, Dove S, Seifert R, Elz S, Buschauer A. The Bivalent Ligand Approach Leads to Highly Potent and Selective Acylguanidine-Type Histamine H2 Receptor Agonists. J Med Chem 2012; 55:1147-60. [DOI: 10.1021/jm201128q] [Citation(s) in RCA: 39] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/16/2023]
Affiliation(s)
- Tobias Birnkammer
- Department of Pharmaceutical/Medicinal
Chemistry, Faculty of Chemistry and Pharmacy, University of Regensburg, Universitätsstrasse 31, D-93053
Regensburg, Germany
| | - Anja Spickenreither
- Department of Pharmaceutical/Medicinal
Chemistry, Faculty of Chemistry and Pharmacy, University of Regensburg, Universitätsstrasse 31, D-93053
Regensburg, Germany
| | - Irena Brunskole
- Department of Pharmaceutical/Medicinal
Chemistry, Faculty of Chemistry and Pharmacy, University of Regensburg, Universitätsstrasse 31, D-93053
Regensburg, Germany
| | - Miroslaw Lopuch
- Department of Pharmaceutical/Medicinal
Chemistry, Faculty of Chemistry and Pharmacy, University of Regensburg, Universitätsstrasse 31, D-93053
Regensburg, Germany
| | - Nicole Kagermeier
- Department of Pharmaceutical/Medicinal
Chemistry, Faculty of Chemistry and Pharmacy, University of Regensburg, Universitätsstrasse 31, D-93053
Regensburg, Germany
| | - Günther Bernhardt
- Department of Pharmaceutical/Medicinal
Chemistry, Faculty of Chemistry and Pharmacy, University of Regensburg, Universitätsstrasse 31, D-93053
Regensburg, Germany
| | - Stefan Dove
- Department of Pharmaceutical/Medicinal
Chemistry, Faculty of Chemistry and Pharmacy, University of Regensburg, Universitätsstrasse 31, D-93053
Regensburg, Germany
| | - Roland Seifert
- Institute
of Pharmacology, Medical School of Hannover, D-30625 Hannover, Germany
| | - Sigurd Elz
- Department of Pharmaceutical/Medicinal
Chemistry, Faculty of Chemistry and Pharmacy, University of Regensburg, Universitätsstrasse 31, D-93053
Regensburg, Germany
| | - Armin Buschauer
- Department of Pharmaceutical/Medicinal
Chemistry, Faculty of Chemistry and Pharmacy, University of Regensburg, Universitätsstrasse 31, D-93053
Regensburg, Germany
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12
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N-Alkenyl and cycloalkyl carbamates as dual acting histamine H3 and H4 receptor ligands. Bioorg Med Chem 2011; 19:2850-8. [DOI: 10.1016/j.bmc.2011.03.046] [Citation(s) in RCA: 20] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/10/2010] [Revised: 03/10/2011] [Accepted: 03/18/2011] [Indexed: 11/19/2022]
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13
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Sun X, Li Y, Li W, Xu Z, Tang Y. Computational investigation of interactions between human H2 receptor and its agonists. J Mol Graph Model 2011; 29:693-701. [DOI: 10.1016/j.jmgm.2010.12.001] [Citation(s) in RCA: 17] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/19/2010] [Revised: 11/23/2010] [Accepted: 12/04/2010] [Indexed: 11/16/2022]
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14
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Igel P, Dove S, Buschauer A. Histamine H4 receptor agonists. Bioorg Med Chem Lett 2010; 20:7191-9. [PMID: 21044842 DOI: 10.1016/j.bmcl.2010.10.041] [Citation(s) in RCA: 21] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/24/2010] [Accepted: 10/08/2010] [Indexed: 10/18/2022]
Abstract
Since its discovery 10 years ago the histamine H(4) receptor (H(4)R) has attracted attention as a potential drug target, for instance, for the treatment of inflammatory and allergic diseases. Potent and selective ligands including agonists are required as pharmacological tools to study the role of the H(4)R in vitro and in vivo. Many H(4)R agonists, which were identified among already known histamine receptor ligands, show only low or insufficient H(4)R selectivity. In addition, the investigation of numerous H(4)R agonists in animal models is hampered by species-dependent discrepancies regarding potencies and histamine receptor selectivities of the available compounds, especially when comparing human and rodent receptors. This article gives an overview about structures, potencies, and selectivities of various compounds showing H(4)R agonistic activity and summarizes the structure-activity relationships of selected compound classes.
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Affiliation(s)
- Patrick Igel
- Department of Pharmaceutical/Medicinal Chemistry, Faculty of Chemistry and Pharmacy, University of Regensburg, Regensburg, Germany
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15
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Straßer A, Wittmann HJ. In silico analysis of the histaprodifen induced activation pathway of the guinea-pig histamine H1-receptor. J Comput Aided Mol Des 2010; 24:759-69. [DOI: 10.1007/s10822-010-9372-2] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/07/2010] [Accepted: 06/28/2010] [Indexed: 10/19/2022]
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Abstract
BACKGROUND The guanidine group defines chemical and physicochemical properties of many compounds of medical interest and guanidine-containing derivatives constitute a very important class of therapeutic agents suitable for the treatment of a wide spectrum of diseases. OBJECTIVE To review the most important pharmacological properties, mechanisms of action and therapeutic uses of simple guanidine derivatives, cyclic analogues of guanidines as well as peptides, peptidomimetics and peptoids incorporating arginine. METHODS The review presents both the recent patent literature and original papers dealing with guanidine derivatives that show interesting biological activity and emphasizes the newest developing drugs. CONCLUSION Recent achievements in the synthesis of guanidine-containing molecules with diverse chemical, biochemical and pharmacological properties make them of great importance to the design and development of novel drugs acting at CNS, anti-inflammatory agents, inhibitors of Na(+)/H(+) exchanger, inhibitors of NO synthase, antithrombotic, antidiabetic and chemotherapeutic agents as well as guanidinium-based transporters and vectors.
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Affiliation(s)
- Franciszek Saczewski
- Department of Chemical Technology of Drugs, Medical University of Gdansk, Al. Gen. Hallera 107, Gdansk, Poland.
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17
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Igel P, Geyer R, Strasser A, Dove S, Seifert R, Buschauer A. Synthesis and structure-activity relationships of cyanoguanidine-type and structurally related histamine H4 receptor agonists. J Med Chem 2009; 52:6297-313. [PMID: 19791743 DOI: 10.1021/jm900526h] [Citation(s) in RCA: 52] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Abstract
Recently, we identified high-affinity human histamine H3 (hH3R) and H4 receptor (hH4R) ligands among a series of NG-acylated imidazolylpropylguanidines, which were originally designed as histamine H2 receptor (H2R) agonists. Aiming at selectivity for hH4R, the acylguanidine group was replaced with related moieties. Within a series of cyanoguanidines, 2-cyano-1-[4-(1H-imidazol-4-yl)butyl]-3-[(2-phenylthio)ethyl]guanidine (UR-PI376, 67) was identified as the most potent hH4R agonist (pEC50 = 7.47, alpha = 0.93) showing negligible hH1R and hH2R activities and significant selectivity over the hH3R (pKB = 6.00, alpha = -0.28), as determined in steady-state GTPase assays using membrane preparations of hH(x)R-expressing Sf9 cells. In contrast to previously described selective H4R agonists, this compound and other 3-substituted derivatives are devoid of agonistic activity at the other HR subtypes. Modeling of the binding mode of 67 suggests that the cyanoguanidine moiety forms charge-assisted hydrogen bonds not only with the conserved Asp-94 but also with the hH4R-specific Arg-341 residue. 2-Carbamoyl-1-[2-(1H-imidazol-4-yl)ethyl]-3-(3-phenylpropyl)guanidine (UR-PI97, 88) was unexpectedly identified as a highly potent and selective hH3R inverse agonist (pKB = 8.42, >300-fold selectivity over the other HR subtypes).
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Affiliation(s)
- Patrick Igel
- Department of Pharmaceutical/Medicinal Chemistry, Faculty of Chemistry and Pharmacy, University of Regensburg, Universitatsstrasse 31, D-93053 Regensburg, Germany
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18
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Wittmann HJ, Seifert R, Strasser A. Contribution of binding enthalpy and entropy to affinity of antagonist and agonist binding at human and guinea pig histamine H(1)-receptor. Mol Pharmacol 2009; 76:25-37. [PMID: 19346300 DOI: 10.1124/mol.109.055384] [Citation(s) in RCA: 27] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022] Open
Abstract
For several GPCRs, discrimination between agonism and antagonism is possible on the basis of thermodynamics parameters, such as binding enthalpy and entropy. In this study, we analyze whether agonists and antagonists can also be discriminated thermodynamically at the histamine H(1) receptor (H(1)R). Because previous studies revealed species differences in pharmacology between human H(1)R (hH(1)R) and guinea pig H(1)R (gpH(1)R), we analyzed a broad spectrum of H(1)R antagonists and agonists at hH(1)R and gpH(1)R. [(3)H]Mepyramine competition binding assay were performed at five different temperatures in a range from 283.15 to 303.15 K. In addition, we performed a temperature-dependent three-dimensional quantitative structure activity relationship study to predict binding enthalpy and entropy for histaprodifen derivatives, which can bind to H(1)R in two different orientations. Our studies revealed significant species differences in binding enthalpy and entropy between hH(1)R and gpH(1)R for some antagonists and agonists. Furthermore, in some cases, we found changes in heat capacity of the binding process that were different from zero. Differences in flexibility of the ligands may be responsible for this observation. For most ligands, the binding process to hH(1)R and gpH(1)R is clearly entropy-driven. In contrast, for the endogenous ligand histamine, the binding process is significantly enthalpy-driven at both species isoforms. Thus, a definite discrimination between antagonism and agonism based on thermodynamic parameters is possible for neither hH(1)R nor gpH(1)R, but thermodynamic analysis of ligand-binding may be a novel approach to dissect agonist- and antagonist-specific receptor conformations.
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Affiliation(s)
- Hans-Joachim Wittmann
- Faculty of Chemistry and Pharmacy, School of Pharmacy, University of Regensburg, Regensburg, Germany
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19
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Igel P, Schneider E, Schnell D, Elz S, Seifert R, Buschauer A. NG-Acylated Imidazolylpropylguanidines as Potent Histamine H4 Receptor Agonists: Selectivity by Variation of the NG-Substituent. J Med Chem 2009; 52:2623-7. [DOI: 10.1021/jm9000693] [Citation(s) in RCA: 44] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Affiliation(s)
- Patrick Igel
- Department of Pharmaceutical/Medicinal Chemistry and Department of Pharmacology and Toxicology, Faculty of Chemistry and Pharmacy, University of Regensburg, Universitätsstrasse 31, D-93053 Regensburg, Germany, and Institute of Pharmacology, Medical School of Hannover, D-30625 Hannover, Germany
| | - Erich Schneider
- Department of Pharmaceutical/Medicinal Chemistry and Department of Pharmacology and Toxicology, Faculty of Chemistry and Pharmacy, University of Regensburg, Universitätsstrasse 31, D-93053 Regensburg, Germany, and Institute of Pharmacology, Medical School of Hannover, D-30625 Hannover, Germany
| | - David Schnell
- Department of Pharmaceutical/Medicinal Chemistry and Department of Pharmacology and Toxicology, Faculty of Chemistry and Pharmacy, University of Regensburg, Universitätsstrasse 31, D-93053 Regensburg, Germany, and Institute of Pharmacology, Medical School of Hannover, D-30625 Hannover, Germany
| | - Sigurd Elz
- Department of Pharmaceutical/Medicinal Chemistry and Department of Pharmacology and Toxicology, Faculty of Chemistry and Pharmacy, University of Regensburg, Universitätsstrasse 31, D-93053 Regensburg, Germany, and Institute of Pharmacology, Medical School of Hannover, D-30625 Hannover, Germany
| | - Roland Seifert
- Department of Pharmaceutical/Medicinal Chemistry and Department of Pharmacology and Toxicology, Faculty of Chemistry and Pharmacy, University of Regensburg, Universitätsstrasse 31, D-93053 Regensburg, Germany, and Institute of Pharmacology, Medical School of Hannover, D-30625 Hannover, Germany
| | - Armin Buschauer
- Department of Pharmaceutical/Medicinal Chemistry and Department of Pharmacology and Toxicology, Faculty of Chemistry and Pharmacy, University of Regensburg, Universitätsstrasse 31, D-93053 Regensburg, Germany, and Institute of Pharmacology, Medical School of Hannover, D-30625 Hannover, Germany
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20
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Kraus A, Ghorai P, Birnkammer T, Schnell D, Elz S, Seifert R, Dove S, Bernhardt G, Buschauer A. NG-Acylated Aminothiazolylpropylguanidines as Potent and Selective Histamine H2Receptor Agonists. ChemMedChem 2009; 4:232-40. [DOI: 10.1002/cmdc.200800296] [Citation(s) in RCA: 38] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/10/2022]
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21
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Ghorai P, Kraus A, Keller M, Götte C, Igel P, Schneider E, Schnell D, Bernhardt G, Dove S, Zabel M, Elz S, Seifert R, Buschauer A. Acylguanidines as Bioisosteres of Guanidines: NG-Acylated Imidazolylpropylguanidines, a New Class of Histamine H2 Receptor Agonists. J Med Chem 2008; 51:7193-204. [DOI: 10.1021/jm800841w] [Citation(s) in RCA: 62] [Impact Index Per Article: 3.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Affiliation(s)
- Prasanta Ghorai
- Departments of Pharmaceutical/Medicinal Chemistry, Pharmacology and Toxicology, Center for Chemical Analysis, Faculty of Chemistry and Pharmacy, University of Regensburg, Universitätsstrasse 31, D-93053 Regensburg, Germany
| | - Anja Kraus
- Departments of Pharmaceutical/Medicinal Chemistry, Pharmacology and Toxicology, Center for Chemical Analysis, Faculty of Chemistry and Pharmacy, University of Regensburg, Universitätsstrasse 31, D-93053 Regensburg, Germany
| | - Max Keller
- Departments of Pharmaceutical/Medicinal Chemistry, Pharmacology and Toxicology, Center for Chemical Analysis, Faculty of Chemistry and Pharmacy, University of Regensburg, Universitätsstrasse 31, D-93053 Regensburg, Germany
| | - Carsten Götte
- Departments of Pharmaceutical/Medicinal Chemistry, Pharmacology and Toxicology, Center for Chemical Analysis, Faculty of Chemistry and Pharmacy, University of Regensburg, Universitätsstrasse 31, D-93053 Regensburg, Germany
| | - Patrick Igel
- Departments of Pharmaceutical/Medicinal Chemistry, Pharmacology and Toxicology, Center for Chemical Analysis, Faculty of Chemistry and Pharmacy, University of Regensburg, Universitätsstrasse 31, D-93053 Regensburg, Germany
| | - Erich Schneider
- Departments of Pharmaceutical/Medicinal Chemistry, Pharmacology and Toxicology, Center for Chemical Analysis, Faculty of Chemistry and Pharmacy, University of Regensburg, Universitätsstrasse 31, D-93053 Regensburg, Germany
| | - David Schnell
- Departments of Pharmaceutical/Medicinal Chemistry, Pharmacology and Toxicology, Center for Chemical Analysis, Faculty of Chemistry and Pharmacy, University of Regensburg, Universitätsstrasse 31, D-93053 Regensburg, Germany
| | - Günther Bernhardt
- Departments of Pharmaceutical/Medicinal Chemistry, Pharmacology and Toxicology, Center for Chemical Analysis, Faculty of Chemistry and Pharmacy, University of Regensburg, Universitätsstrasse 31, D-93053 Regensburg, Germany
| | - Stefan Dove
- Departments of Pharmaceutical/Medicinal Chemistry, Pharmacology and Toxicology, Center for Chemical Analysis, Faculty of Chemistry and Pharmacy, University of Regensburg, Universitätsstrasse 31, D-93053 Regensburg, Germany
| | - Manfred Zabel
- Departments of Pharmaceutical/Medicinal Chemistry, Pharmacology and Toxicology, Center for Chemical Analysis, Faculty of Chemistry and Pharmacy, University of Regensburg, Universitätsstrasse 31, D-93053 Regensburg, Germany
| | - Sigurd Elz
- Departments of Pharmaceutical/Medicinal Chemistry, Pharmacology and Toxicology, Center for Chemical Analysis, Faculty of Chemistry and Pharmacy, University of Regensburg, Universitätsstrasse 31, D-93053 Regensburg, Germany
| | - Roland Seifert
- Departments of Pharmaceutical/Medicinal Chemistry, Pharmacology and Toxicology, Center for Chemical Analysis, Faculty of Chemistry and Pharmacy, University of Regensburg, Universitätsstrasse 31, D-93053 Regensburg, Germany
| | - Armin Buschauer
- Departments of Pharmaceutical/Medicinal Chemistry, Pharmacology and Toxicology, Center for Chemical Analysis, Faculty of Chemistry and Pharmacy, University of Regensburg, Universitätsstrasse 31, D-93053 Regensburg, Germany
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22
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Preuss H, Ghorai P, Kraus A, Dove S, Buschauer A, Seifert R. Point mutations in the second extracellular loop of the histamine H2 receptor do not affect the species-selective activity of guanidine-type agonists. Naunyn Schmiedebergs Arch Pharmacol 2007; 376:253-64. [DOI: 10.1007/s00210-007-0204-4] [Citation(s) in RCA: 17] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/10/2007] [Accepted: 10/15/2007] [Indexed: 12/23/2022]
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23
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Xie SX, Schalkhausser F, Ye QZ, Seifert R, Buschauer A. Effects of impromidine- and arpromidine-derived guanidines on recombinant human and guinea pig histamine H1 and H2 receptors. Arch Pharm (Weinheim) 2007; 340:9-16. [PMID: 17206612 DOI: 10.1002/ardp.200600140] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/07/2022]
Abstract
Imidazolylpropylguanidines derived from impromidine and arpromidine are more potent and efficacious agonists at the guinea pig histamine H2 receptor (gpH2R) than at the human H2R (hH2R) in the GTPase assay. Additionally, such guanidines are histamine H1 receptor (H1R) antagonists with preference for the human relative to the guinea pig receptor. The purpose of this study was to examine structure-activity relationships of guanidines at human and guinea pig H1R and H2R species isoforms expressed in Sf9 insect cells. Three impromidine analogues and six arpromidine analogues exhibited agonistic activity at H2R and antagonistic activity at H1R as assessed in the steady-state GTPase assay. Species selectivity of derivatives was similar as compared with the parent compounds. None of the structural modifications examined (different aromatic ring systems and different ring substituents) was superior in terms of H2R potency and efficacy relative to impromidine and arpromidine, respectively. These data point to substantial structural constraints at the agonist binding site of H2R. Guanidines exhibited distinct structure-activity relationships for H1R antagonism in a radioligand competition binding assay and the GTPase assay and for H1R inverse agonism. Our data indicate that it is difficult to obtain guanidine-type agonists with high potency and high efficacy for hH2R, but those compounds may be useful tools for exploring the antagonist binding site and constitutive activity of H1R.
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MESH Headings
- Animals
- Binding, Competitive
- Cell Line
- GTP Phosphohydrolases/metabolism
- GTP-Binding Protein alpha Subunits, Gq-G11/drug effects
- GTP-Binding Protein alpha Subunits, Gq-G11/genetics
- GTP-Binding Protein alpha Subunits, Gs/drug effects
- GTP-Binding Protein alpha Subunits, Gs/genetics
- Guanidines/chemistry
- Guanidines/metabolism
- Guanidines/pharmacology
- Guinea Pigs
- Histamine Agonists/chemistry
- Histamine Agonists/metabolism
- Histamine Agonists/pharmacology
- Histamine H1 Antagonists/chemistry
- Histamine H1 Antagonists/metabolism
- Histamine H1 Antagonists/pharmacology
- Humans
- Imidazoles/chemistry
- Imidazoles/metabolism
- Imidazoles/pharmacology
- Impromidine/analogs & derivatives
- Impromidine/chemistry
- Impromidine/metabolism
- Impromidine/pharmacology
- Insecta
- Molecular Structure
- Pyrilamine/metabolism
- Receptors, Histamine H1/drug effects
- Receptors, Histamine H1/genetics
- Receptors, Histamine H1/metabolism
- Receptors, Histamine H2/drug effects
- Receptors, Histamine H2/genetics
- Receptors, Histamine H2/metabolism
- Recombinant Fusion Proteins/drug effects
- Structure-Activity Relationship
- Transfection
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Affiliation(s)
- Sheng-Xue Xie
- High Throughput Screening Laboratory, University of Kansas, Lawrence, USA
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24
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Preuss H, Ghorai P, Kraus A, Dove S, Buschauer A, Seifert R. Mutations of Cys-17 and Ala-271 in the human histamine H2 receptor determine the species selectivity of guanidine-type agonists and increase constitutive activity. J Pharmacol Exp Ther 2007; 321:975-82. [PMID: 17347323 DOI: 10.1124/jpet.107.120519] [Citation(s) in RCA: 15] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022] Open
Abstract
In a steady-state GTPase activity assay, N-[3-(1H-imidazol-4-yl)propyl)]guanidines and N(G)-acylated derivatives are more potent and efficacious at fusion proteins of guinea pig (gpH(2)R-G(salphaS)) than human (hH(2)R-G(salphaS)) histamine H(2) receptor, coupled to the short splice variant of G(salpha), G(salphaS). Whereas Ala-271 (hH(2)R) and Asp-271 (gpH(2)R) in transmembrane domain 7 were identified to determine the potency differences of guanidine-type agonists, the molecular basis for the efficacy differences remains to be elucidated. A homology model of the gpH(2)R suggested that an H-bond between Tyr-17 and Asp-271 stabilizes an active receptor conformation of the gpH(2)R. In the present study, we generated a mutant hH(2)R-G(salphaS) with Cys-17--> Tyr-17/Ala-271--> Asp-271 exchanges (hH(2)R-->gpH(2)R) that exhibited an enhanced level of constitutive GTPase activity and adenylyl cyclase activity compared with wild-type hH(2)R-G(salphaS) and gpH(2)R-G(salphaS). Potencies and efficacies of guanidines and N(G)-acylguanidines were increased at this mutant receptor compared with hH(2)R-G(salphaS), but they were still lower than at gpH(2)R-G(salphaS), suggesting that aside from Tyr-17 and Asp-271 additional amino acids contribute to the distinct pharmacological profiles of both species isoforms. Another hH(2)R-G(salphaS) mutant with a Cys-17--> Tyr-17 exchange showed inefficient coupling to G(salphaS) as revealed by reduced agonist-stimulated GTPase and basal adenylyl cyclase activities. Collectively, our present pharmacological study confirms the existence of an H-bond between Tyr-17 and Asp-271 favoring the stabilization of an active receptor conformation. Distinct potencies and efficacies of agonists and inverse agonists further support the concept of ligand-specific conformations in wild-type and mutant H(2)R-G(salphaS) fusion proteins.
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Affiliation(s)
- Hendrik Preuss
- Department of Pharmaceutical/Medicinal Chemistry II, Institute of Pharmacy, University of Regensburg, Regensburg, Germany
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Preuss H, Ghorai P, Kraus A, Dove S, Buschauer A, Seifert R. Constitutive activity and ligand selectivity of human, guinea pig, rat, and canine histamine H2 receptors. J Pharmacol Exp Ther 2007; 321:983-95. [PMID: 17332265 DOI: 10.1124/jpet.107.120014] [Citation(s) in RCA: 30] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022] Open
Abstract
Previous studies revealed pharmacological differences between human and guinea pig histamine H(2) receptors (H(2)Rs) with respect to the interaction with guanidine-type agonists. Because H(2)R species variants are structurally very similar, comparative studies are suited to relate different properties of H(2)R species isoforms to few molecular determinants. Therefore, we systematically compared H(2)Rs of human (h), guinea pig (gp), rat (r), and canine (c). Fusion proteins of hH(2)R, gpH(2)R, rH(2)R, and cH(2)R, respectively, and the short splice variant of G(salpha), G(salphaS), were expressed in Sf9 insect cells. In the membrane steady-state GTPase activity assay, cH(2)R-G(salphaS) but neither gpH(2)R-G(salphaS) nor rH(2)R-G(salphaS) showed the hallmarks of increased constitutive activity compared with hH(2)R-G(salphaS), i.e., increased efficacies of partial agonists, increased potencies of agonists with the extent of potency increase being correlated with the corresponding efficacies at hH(2)R-G(salphaS), increased inverse agonist efficacies, and decreased potencies of antagonists. Furthermore, in membranes expressing nonfused H(2)Rs without or together with mammalian G(salphaS) or H(2)R-G(salpha) fusion proteins, the highest basal and GTP-dependent increases in adenylyl cyclase activity were observed for cH(2)R. An example of ligand selectivity is given by metiamide, acting as an inverse agonist at hH(2)R-G(salphaS), gpH(2)R-G(salphaS), and rH(2)R-G(salphaS) in the GTPase assay in contrast to being a weak partial agonist with decreased potency at cH(2)R-G(salphaS). In conclusion, the cH(2)R exhibits increased constitutive activity compared with hH(2)R, gpH(2)R, and rH(2)R, and there is evidence for ligand-specific conformations in H(2)R species isoforms.
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Affiliation(s)
- Hendrik Preuss
- Department of Pharmaceutical/Medicinal Chemistry II, Institute of Pharmacy, University of Regensburg, Regensburg, Germany
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Xie SX, Petrache G, Schneider E, Ye QZ, Bernhardt G, Seifert R, Buschauer A. Synthesis and pharmacological characterization of novel fluorescent histamine H2-receptor ligands derived from aminopotentidine. Bioorg Med Chem Lett 2006; 16:3886-90. [PMID: 16730977 DOI: 10.1016/j.bmcl.2006.05.039] [Citation(s) in RCA: 17] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/24/2006] [Revised: 05/11/2006] [Accepted: 05/13/2006] [Indexed: 11/25/2022]
Abstract
In an effort to develop a non-radioactive alternative to the [3H]tiotidine and [125I]iodoaminopotentidine binding assays for the histamine H2-receptor (H2R), primary amines related to aminopotentidine were prepared and coupled with the succinimidyl esters of the bulky fluorescent dyes S0536 and BODIPY 650/665-X. The primary amines exhibited different degrees of antagonistic potency at the human and guinea pig H2R. Surprisingly, one compound (5) coupled to the cyanine dye S0536 acted as potent partial agonist/antagonist at the H2R (KB approximately 50 nM; EC50 approximately 100-150 nM). Compounds coupled to the BODIPY dye exhibited moderately high H2R-affinity, too. Thus, the H2R accommodates bulky fluorophores, probably through interaction with extracellular receptor domains. The compounds presented herein provide a starting point for the optimization of fluorescent H2R ligands with respect to affinity and fluorescence as valuable tools to analyze the molecular mechanisms of H2R activation.
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Affiliation(s)
- Sheng-Xue Xie
- High Throughput Screening Laboratory, The University of Kansas, Lawrence, KS 66045, USA
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27
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Xie SX, Kraus A, Ghorai P, Ye QZ, Elz S, Buschauer A, Seifert R. N1-(3-Cyclohexylbutanoyl)-N2-[3-(1H-imidazol-4-yl)propyl]guanidine (UR-AK57), a Potent Partial Agonist for the Human Histamine H1- and H2-Receptors. J Pharmacol Exp Ther 2006; 317:1262-8. [PMID: 16554355 DOI: 10.1124/jpet.106.102897] [Citation(s) in RCA: 19] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022] Open
Abstract
Both the histamine H1-receptor (H1R) and H2-receptor (H2R) exhibit pronounced species selectivity in their pharmacological properties; i.e., bulky agonists possess higher potencies and efficacies at guinea pig (gp) than at the corresponding human (h) receptor isoforms. In this study, we examined the effects of NG-acylated imidazolylpropylguanidines substituted with a single phenyl or cyclohexyl substituent on H1R and H2R species isoforms expressed in Sf9 insect cells. N1-(3-Cyclohexylbutanoyl)-N2-[3-(1H-imidazol-4-yl)propyl]guanidine (UR-AK57) turned out to be the most potent hH2R agonist identified so far (EC50 of 23 nM in the GTPase assay at the hH2R-Gsalpha fusion protein expressed in Sf9 insect cells). UR-AK57 was almost a full-hH2R agonist and only slightly less potent and efficacious than at gpH2R-Gsalpha. Several NG-acylated imidazolylpropylguanidines showed similar potency at hH2R and gpH2R. Most unexpectedly, UR-AK57 exhibited moderately strong partial hH1R agonism with a potency similar to that of histamine, whereas at gpH1R, UR-AK57 was only a very weak partial agonist. Structure/activity relationship studies revealed that both the alkanoyl chain connecting the aromatic or alicyclic substituent with the guanidine moiety and the nature of the carbocycle (cyclohexyl versus phenyl ring) critically determine the pharmacological properties of this class of compounds. Collectively, our data show that gpH1R and gpH R do not necessarily exhibit preference for bulky agonists (2) compared with hH1R and hH2R, respectively, and that UR-AK57 is a promising starting point for the development of both potent and efficacious hH1R and hH2R agonists.
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Affiliation(s)
- Sheng-Xue Xie
- High-Throughput Screening Laboratory, University of Kansas, Lawrence, Kansas, USA
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