30 research outputs found

    Steps towards collective sustainability in biomedical research

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    The optimism surrounding multistakeholder research initiatives does not match the clear view of policies that are needed to exploit the potential of these collaborations. Here we propose some action items that stem from the integration between research advancements with the perspectives of patient-advocacy organizations, academia, and industry

    G PROTEIN-COUPLED RECEPTOR DESENSITISATION REGULATES STEM CELL DIFFERENTIATION

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    G-protein coupled receptors (GPCRs) play a key role in many complex biological processes, including regulation of stem cell pluripotency and differentiation. Signal transduction pathways that are activated during stem cell renewal and differentiation are shared, cross-activated or synergistic with GPCR stimulation [1]. Regulation of GPCR responses involved the activation of desensitization machinery, which started with phosphorylation of agonist-activated receptor by second messenger-dependent and/or GPCR kinases (GRKs)[1]. Besides controlling receptor responsiveness, GRKs can also act as agonist-regulated scaffolds assembling macromolecular signalosomes in the receptor environment, thereby contributing to signal propagation from cytosol to nucleus, and controlling gene transcription machinery [2]. Recent evidence suggests that the desensitization machinery fulfils a vital role in regulating cellular responses to GPCRs, and that changes in expression/functioning of these regulatory proteins may be crucial in the control of cell differentiation program [3]. These data are consistent with the notion that GPCR responsiveness may be differentially regulated during cell differentiation. In our hands, two different cellular models (oligodendrocyte precursor cells, OPCs, and mesenchymal stem cells, MSCs) were used to investigate the role of the GPCR desensitisation machinery in stem cell differentiation. During OPC differentiation, defective control of the membrane receptor GPR17 has been suggested to block cell maturation and impairs remyelination under demyelinating conditions [4]. Here we show, for the first time, a role for Murine double minute 2 (Mdm2), a ligase previously involved in ubiquitination/degradation of p53 protein. In maturing OPCs, the inhibition of Mdm2-p53 interactions increased GRK2 sequestration by Mdm2, leading to impaired GPR17 down-regulation and OPC maturation block. In MSCs, the A2B adenosine receptor (A2BAR) has been recently emerged as the major AR involved in osteoblastogenesis [5]. Proinflammatory cytokines, such as Tumour Necrosis Factor- (TNF-, have been demonstrated to regulate MSC differentiation and bone remodelling. Herein, we show that TNF- diminished GRK2 levels in MSCs, thus blocking A2BAR desensitization. As a result, TNF- enhanced the A2BAR-mediated responses and favoured MSC differentiation to osteoblasts in response to receptor agonists. The findings get new insights for discovering of the signals at the basis of cell differentiation

    Surface Plasmon Resonance as a Tool for Ligand Binding Investigation of Engineered GPR17 Receptor, a G Protein Coupled Receptor Involved in Myelination

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    The aim of this study was to investigate the potential of surface plasmon resonance (SPR) spectroscopy for the measurement of real-time ligand-binding affinities and kinetic parameters for GPR17, a G protein-coupled receptor (GPCR) of major interest in medicinal chemistry as potential target in demyelinating diseases. The receptor was directly captured, in a single-step, from solubilized membrane extracts on the sensor chip through a covalently bound anti-6x-His-antibody and retained its ligand binding activity for over 24h. Furthermore, our experimental setup made possible, after a mild regeneration step, to remove the bound receptor without damaging the antibody, and thus to reuse many times the same chip. Two engineered variants of GPR17, designed for crystallographic studies, were expressed in insect cells, extracted from crude membranes and analyzed for their binding with two high affinity ligands: the antagonist Cangrelor and the agonist Asinex 1. The calculated kinetic parameters and binding constants of ligands were in good agreement with those reported from activity assays and highlighted a possible functional role of the N-terminal residues of the receptor in ligand recognition and binding. Validation of SPR results was obtained by docking and molecular dynamics of GPR17-ligands interactions and by functional in vitro studies. The latter allowed us to confirm that Asinex 1 behaves as GPR17 receptor agonist, inhibits forskolin-stimulated adenylyl cyclase pathway and promotes oligodendrocyte precursor cell maturation and myelinating ability

    P2Y receptors in GtoPdb v.2021.3

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    P2Y receptors (nomenclature as agreed by the NC-IUPHAR Subcommittee on P2Y Receptors [3, 5, 192]) are activated by the endogenous ligands ATP, ADP, uridine triphosphate, uridine diphosphate and UDP-glucose. The relationship of many of the cloned receptors to endogenously expressed receptors is not yet established and so it might be appropriate to use wording such as 'uridine triphosphate-preferring (or ATP-, etc.) P2Y receptor' or 'P2Y1-like', etc., until further, as yet undefined, corroborative criteria can be applied [47, 110, 190, 383, 396]. Clinically used drugs acting on these receptors include the dinucleoside polyphosphate diquafosol, agonist of the P2Y2 receptor subtype, approved in Japan for the management of dry eye disease [241], and the P2Y12 receptor antagonists prasugrel, ticagrelor and cangrelor, all approved as antiplatelet drugs [53, 323]

    P2Y receptors (version 2019.4) in the IUPHAR/BPS Guide to Pharmacology Database

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    P2Y receptors (nomenclature as agreed by the NC-IUPHAR Subcommittee on P2Y Receptors [3, 5]) are activated by the endogenous ligands ATP, ADP, uridine triphosphate, uridine diphosphate and UDP-glucose. The relationship of many of the cloned receptors to endogenously expressed receptors is not yet established and so it might be appropriate to use wording such as 'uridine triphosphate-preferring (or ATP-, etc.) P2Y receptor' or 'P2Y1-like', etc., until further, as yet undefined, corroborative criteria can be applied [46, 109, 187, 375, 388].Clinically used drugs acting on these receptors include the dinucleoside polyphosphate diquafosol, agonist of the P2Y2 receptor subtype, approved in Japan for the management of dry eye disease [236], and the P2Y12 receptor antagonists prasugrel, ticagrelor and cangrelor, all approved as antiplatelet drugs [52, 316]

    P2Y receptors in GtoPdb v.2023.1

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    P2Y receptors (nomenclature as agreed by the NC-IUPHAR Subcommittee on P2Y Receptors [3, 5, 189]) are activated by the endogenous ligands ATP, ADP, UTP, UDP, UDP-glucose and adenosine. The eight mammalian P2Y receptors are activated by distinct nucleotides: P2Y1, P2Y11, P2Y12 and P2Y13 are activated by adenosine-nucleotides; P2Y2, P2Y4 can be activated by both adenosine and uridine nucleotides, with some species-specific differences; P2Y6 is mainly activated by UDP; P2Y14 is preferentially activated by sugar-uracil nucleotides. The missing numbers in the receptor nomenclature refer either to non-mammalian orthologs or receptors having some sequence homology to P2Y receptors but for which there is no functional evidence of responsiveness to nucleotides [380]. Based on their G protein coupling P2Y receptors can be divided into two subfamilies: P2Y1, P2Y2, P2Y4, P2Y6 and P2Y11 receptors couple via Gq proteins to stimulate phospholipase C followed by increases in inositol phosphates and mobilization of Ca2+ from intracellular stores. P2Y11 receptors couple in addition to Gs proteins followed by increased adenylate cyclase activity. In contrast, P2Y12, P2Y13, and P2Y14 receptors signal primarily through activation of Gi proteins and inhibition of adenylate cyclase activity or control of ion channel activity [380]. Clinically used drugs acting on these receptors include the dinucleoside polyphosphate diquafosol, agonist of the P2Y2 receptor subtype, approved in Japan and South Korea for the management of dry eye disease [238], and the P2Y12 receptor antagonists prasugrel, ticagrelor and cangrelor, all approved as antiplatelet drugs [52, 320]

    THE CONCISE GUIDE TO PHARMACOLOGY 2021/22: G protein-coupled receptors

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    The Concise Guide to PHARMACOLOGY 2021/22 is the fifth in this series of biennial publications. The Concise Guide provides concise overviews, mostly in tabular format, of the key properties of nearly 1900 human drug targets with an emphasis on selective pharmacology (where available), plus links to the open access knowledgebase source of drug targets and their ligands (www.guidetopharmacology.org), which provides more detailed views of target and ligand properties. Although the Concise Guide constitutes over 500 pages, the material presented is substantially reduced compared to information and links presented on the website. It provides a permanent, citable, point-in-time record that will survive database updates. The full contents of this section can be found at http://onlinelibrary.wiley.com/doi/bph.15538. G protein-coupled receptors are one of the six major pharmacological targets into which the Guide is divided, with the others being: ion channels, nuclear hormone receptors, catalytic receptors, enzymes and transporters. These are presented with nomenclature guidance and summary information on the best available pharmacological tools, alongside key references and suggestions for further reading. The landscape format of the Concise Guide is designed to facilitate comparison of related targets from material contemporary to mid-2021, and supersedes data presented in the 2019/20, 2017/18, 2015/16 and 2013/14 Concise Guides and previous Guides to Receptors and Channels. It is produced in close conjunction with the Nomenclature and Standards Committee of the International Union of Basic and Clinical Pharmacology (NC-IUPHAR), therefore, providing official IUPHAR classification and nomenclature for human drug targets, where appropriate

    THE CONCISE GUIDE TO PHARMACOLOGY 2021/22: G protein-coupled receptors.

    Get PDF
    The Concise Guide to PHARMACOLOGY 2021/22 is the fifth in this series of biennial publications. The Concise Guide provides concise overviews, mostly in tabular format, of the key properties of nearly 1900 human drug targets with an emphasis on selective pharmacology (where available), plus links to the open access knowledgebase source of drug targets and their ligands (www.guidetopharmacology.org), which provides more detailed views of target and ligand properties. Although the Concise Guide constitutes over 500 pages, the material presented is substantially reduced compared to information and links presented on the website. It provides a permanent, citable, point-in-time record that will survive database updates. The full contents of this section can be found at http://onlinelibrary.wiley.com/doi/bph.15538. G protein-coupled receptors are one of the six major pharmacological targets into which the Guide is divided, with the others being: ion channels, nuclear hormone receptors, catalytic receptors, enzymes and transporters. These are presented with nomenclature guidance and summary information on the best available pharmacological tools, alongside key references and suggestions for further reading. The landscape format of the Concise Guide is designed to facilitate comparison of related targets from material contemporary to mid-2021, and supersedes data presented in the 2019/20, 2017/18, 2015/16 and 2013/14 Concise Guides and previous Guides to Receptors and Channels. It is produced in close conjunction with the Nomenclature and Standards Committee of the International Union of Basic and Clinical Pharmacology (NC-IUPHAR), therefore, providing official IUPHAR classification and nomenclature for human drug targets, where appropriate
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