ABSTRACT
Prostaglandins E1 and E2 are synthesized in the intestine and mediate a range of gastrointestinal functions via activation of the prostanoid E type (EP) family of receptors. We examined the potential role of EP receptors in the regulation of gut hormone secretion from L cells. Analysis of mRNA expression in mouse enteroendocrine GLUTag cells demonstrated the abundant expression of EP4 receptor, whereas expression of other EP receptors was much lower. Prostaglandin E1 and E2, nonselective agonists for all EP receptor subtypes, triggered glucagon like peptide 1 (GLP-1) secretion from GLUTag cells, as did the EP4-selective agonists CAY10580 and TCS2510. The effect of EP4 agonists on GLP-1 secretion was blocked by incubation of cells with the EP4-selective antagonist L161,982 or by down-regulating EP4 expression with specific small interfering RNA. Regulation of gut hormone secretion with EP4 agonists was further studied in mice. Administration of EP4 agonists to mice produced a significant elevation of plasma levels of GLP-1, glucagon like peptide 2 (GLP-2) and peptide YY (PYY), whereas gastric inhibitory peptide (GIP) levels were not increased. Thus, our data demonstrate that activation of the EP4 receptor in enteroendocrine L cells triggers secretion of gut hormones.
Subject(s)
Glucagon-Like Peptide 1/blood , Glucagon-Like Peptide 2/blood , Peptide YY/blood , Receptors, Prostaglandin E, EP4 Subtype/metabolism , Animals , Cells, Cultured , Gastric Inhibitory Polypeptide/blood , Intestinal Mucosa/metabolism , Mice , Real-Time Polymerase Chain Reaction , Receptors, Prostaglandin E, EP4 Subtype/antagonists & inhibitors , Receptors, Prostaglandin E, EP4 Subtype/genetics , Thiophenes/pharmacology , Triazoles/pharmacologyABSTRACT
Several P4 domain derivatives of the general d-phenylglycinamide-based scaffold (2) were synthesized and evaluated for their ability to bind to the serine protease factor Xa. Some of the more potent compounds were evaluated for their anticoagulant effects in vitro. A select subset containing various P1 indole constructs was further evaluated for their pharmacokinetic properties after oral administration to rats.
Subject(s)
Antithrombin III/chemical synthesis , Antithrombin III/pharmacology , Glycine/analogs & derivatives , Anticoagulants/chemical synthesis , Anticoagulants/chemistry , Anticoagulants/pharmacology , Antithrombin III/chemistry , Crystallography, X-Ray , Factor Xa/chemistry , Factor Xa/metabolism , Glycine/chemical synthesis , Glycine/chemistry , Glycine/pharmacology , Humans , Models, Molecular , Molecular Structure , Protein Binding , Structure-Activity RelationshipABSTRACT
Analogs to a series of D-phenylglycinamide-derived factor Xa inhibitors were discovered. It was found that the S4 amide linkage can be replaced with an ether linkage to reduce the peptide character of the molecules and that this substitution leads to an increase in binding affinity that is not predicted based on modeling. Inhibitors which incorporate ether, amino, or alkyl S4 linkage motifs exhibit similar levels of binding affinity and also demonstrate potent in vitro functional activity, however, binding affinity in this series is strongly dependent on the nature of the S1 binding element.
Subject(s)
Anticoagulants/pharmacology , Factor Xa Inhibitors , Glycine/analogs & derivatives , Serine Proteinase Inhibitors/pharmacology , Anticoagulants/chemistry , Crystallography, X-Ray , Ethanolamines , Glycine/chemistry , Models, Molecular , Peptides/chemistry , Serine Proteinase Inhibitors/chemistryABSTRACT
SAR about the B-ring of a series of N(2)-aroyl anthranilamide factor Xa (fXa) inhibitors is described. B-ring o-aminoalkylether and B-ring p-amine probes of the S1' and S4 sites, respectively, afforded picomolar fXa inhibitors that performed well in in vitro anticoagulation assays.
Subject(s)
Antithrombin III/chemical synthesis , Factor Xa Inhibitors , Fluorescent Dyes/pharmacology , ortho-Aminobenzoates/pharmacology , Anticoagulants/chemistry , Antithrombin III/chemistry , Binding Sites , Chemistry, Pharmaceutical/methods , Dose-Response Relationship, Drug , Drug Design , Drug Evaluation, Preclinical , Fluorescent Dyes/chemical synthesis , Humans , Kinetics , Models, Chemical , Molecular Conformation , Structure-Activity Relationship , ortho-Aminobenzoates/chemical synthesisABSTRACT
Several non-amidino S1 derivatives of the 1,2-diaminobenzene-based scaffold (4) were synthesized and evaluated for their ability to bind to the active site and inhibit the human protease factor Xa. A subset of these compounds were also evaluated for their anticoagulant effects in human plasma as measured by prothrombin time (PT).
