ABSTRACT
We report here new chemical series acting as antagonists of melanin-concentrating hormone receptor 1 (MCHR-1). Synthesis and structure-activity relationships are described leading to the identification of compounds with optimized in vitro pharmacological and in vitro ADME profiles. In vivo activity has been demonstrated in animal models of food intake and depression.
Subject(s)
Chemistry, Pharmaceutical/methods , Hydantoins/chemistry , Melanins/chemistry , Receptors, Pituitary Hormone/antagonists & inhibitors , Receptors, Pituitary Hormone/chemistry , Receptors, Somatostatin/antagonists & inhibitors , Animals , Depression/drug therapy , Disease Models, Animal , Drug Design , Feeding Behavior/drug effects , Kinetics , Models, Biological , Models, Chemical , Models, Molecular , Structure-Activity RelationshipABSTRACT
A QSAR model accounting for "average" G-protein-coupled receptor (GPCR) binding was built from a large set of experimental standardized binding data (1939 compounds systematically tested over 40 different GPCRs) and applied to the design of a library of "GPCR-predicted" compounds. Three hundred and sixty of these compounds were randomly selected and tested in 21 GPCR binding assays. Positives were defined by their ability to inhibit by more than 70% the binding of reference compounds at 10 microM. A 5.5-fold enrichment in positives was observed when comparing the "GPCR-predicted" compounds with 600 randomly selected compounds predicted as "non-GPCR" from a general collection. The model was efficient in predicting strongest binders, since enrichment was greater for higher cutoffs. Significant enrichment was also observed for peptidic GPCRs and receptors not included to develop the QSAR model, suggesting the usefulness of the model to design ligands binding with newly identified GPCRs, including orphan ones.
Subject(s)
Ligands , Quantitative Structure-Activity Relationship , Receptors, G-Protein-Coupled/chemistry , Receptors, G-Protein-Coupled/metabolism , Combinatorial Chemistry Techniques , Drug Design , Models, Molecular , Radioligand Assay , Receptors, Chemokine/chemistry , Receptors, Chemokine/metabolism , Receptors, Peptide/chemistry , Receptors, Peptide/metabolismABSTRACT
In plant cells, the synthesis of monogalactosyldiacylglycerol (MGDG) is catalyzed within plastid envelope membranes by MGD proteins. MGDG synthesis was also reported in apicomplexan parasites, a phylum of protists harbouring a plastid that proved essential for the parasite survival. MGD activity is therefore a potent target for herbicidal and anti-parasitic molecules. In this study, we describe a detailed in vitro refolding protocol for denatured recombinant MGD accumulated in inclusion bodies from transformed Escherichia coli. The refolding process was dependent on CHAPS detergent and lipids, such as diacylglycerol and phosphatidylglycerol, as well as bivalent metals. Owing to this refolding procedure, the recombinant MGD protein from spinach was purified to homogeneity, allowing a definite characterization of its non-processivity and an investigation of its dimerization using cross-linking reagents. Additionally, using the portion of recombinant enzyme that accumulates in an active form in bacterial membranes, we developed a miniature assay for high-throughput screening for inhibitors.
