RESUMEN
G protein betagamma subunits have potential as a target for therapeutic treatment of a number of diseases. We performed virtual docking of a small-molecule library to a site on Gbetagamma subunits that mediates protein interactions. We hypothesized that differential targeting of this surface could allow for selective modulation of Gbetagamma subunit functions. Several compounds bound to Gbetagamma subunits with affinities from 0.1 to 60 muM and selectively modulated functional Gbetagamma-protein-protein interactions in vitro, chemotactic peptide signaling pathways in HL-60 leukocytes, and opioid receptor-dependent analgesia in vivo. These data demonstrate an approach for modulation of G protein-coupled receptor signaling that may represent an important therapeutic strategy.
Asunto(s)
Ciclohexanos/metabolismo , Ciclohexanos/farmacología , Evaluación Preclínica de Medicamentos/métodos , Subunidades beta de la Proteína de Unión al GTP/metabolismo , Subunidades gamma de la Proteína de Unión al GTP/metabolismo , Péptidos/metabolismo , Transducción de Señal , Xantenos/metabolismo , Xantenos/farmacología , Analgésicos/farmacología , Animales , Sitios de Unión , Unión Competitiva , Línea Celular , Simulación por Computador , Ciclohexanos/química , Ensayo de Inmunoadsorción Enzimática , Quinasa 2 del Receptor Acoplado a Proteína-G , Subunidades alfa de la Proteína de Unión al GTP/metabolismo , Subunidades beta de la Proteína de Unión al GTP/química , Subunidades gamma de la Proteína de Unión al GTP/química , Células HL-60 , Humanos , Isoenzimas/metabolismo , Ratones , Ratones Endogámicos ICR , Proteínas Quinasas Activadas por Mitógenos/metabolismo , Estructura Molecular , Morfina/farmacología , N-Formilmetionina Leucil-Fenilalanina/metabolismo , Biblioteca de Péptidos , Fosfatidilinositol 3-Quinasas/metabolismo , Fosfolipasa C beta , Unión Proteica , Mapeo de Interacción de Proteínas , Programas Informáticos , Relación Estructura-Actividad , Fosfolipasas de Tipo C/metabolismo , Xantenos/química , Quinasas de Receptores Adrenérgicos beta/metabolismoRESUMEN
A series of homo- and heterodimeric ligands containing kappa agonist and mu agonist/antagonist pharmacophores joined by a linker chain of varying lengths was synthesized and evaluated in vitro by their binding affinity at mu, delta, and kappa opioid receptors. The functional activities of these compounds were measured in the [(35)S]GTPgammaS binding assay. The data suggest that the stereochemistry of the pharmacophores, the N-substituents of the pharmacophore, ester linkages, and the spacer length were crucial factors for optimum interactions of such ligands at opioid receptor binding sites. These novel ligands as well as their pharmacological properties will serve as the basis for our continuing investigation of such bivalent ligands as probes of the opioid receptor oligomerization phenomena and for in vivo studies as analgesics.