ABSTRACT
Stable cell lines that individually express the eight known human prostanoid receptors (EP(1), EP(2), EP(3), EP(4), DP, FP, IP and TP) have been established using human embryonic kidney (HEK) 293(EBNA) cells. These recombinant cell lines have been employed in radioligand binding assays to determine the equilibrium inhibitor constants of known prostanoid receptor ligands at these eight receptors. This has allowed, for the first time, an assessment of the affinity and selectivity of several novel compounds at the individual human prostanoid receptors. This information should facilitate interpretation of pharmacological studies that employ these ligands as tools to study human tissues and cell lines and should, therefore, result in a greater understanding of prostanoid receptor biology.
Subject(s)
Cell Membrane/metabolism , Prostaglandins/metabolism , Receptors, Prostaglandin/metabolism , Binding, Competitive , Cell Line , Humans , Ligands , Radioligand Assay , Receptors, Prostaglandin/agonists , Receptors, Prostaglandin/antagonists & inhibitors , Recombinant Proteins/metabolismABSTRACT
Cyclopentenones containing a 4-(methylsulfonyl)phenyl group in the 3-position and a phenyl ring in the 2-position are selective inhibitors of cyclooxygenase-2 (COX-2). The selectivity for COX-2 over COX-1 is dramatically improved by substituting the 2-phenyl group with halogens in the meta position or by replacing the phenyl ring with a 2- or 3-pyridyl ring. Thus the 3,5-difluorophenyl derivative 7 (L-776,967) and the 3-pyridyl derivative 13 (L-784,506) are particularly interesting as potential antiinflammatory agents with reduced side-effect profiles. Both exhibit good oral bioavailability and are potent in standard models of pain, fever, and inflammation yet have a much reduced effect on the GI integrity of rats compared to standard nonsteroidal antiflammatory drugs.
Subject(s)
Cyclooxygenase Inhibitors/chemical synthesis , Cyclopentanes/chemical synthesis , Isoenzymes/metabolism , Prostaglandin-Endoperoxide Synthases/metabolism , Sulfones/chemical synthesis , Analgesics, Non-Narcotic/chemical synthesis , Analgesics, Non-Narcotic/chemistry , Analgesics, Non-Narcotic/pharmacology , Analgesics, Non-Narcotic/toxicity , Animals , Arthritis, Experimental/drug therapy , Biological Availability , CHO Cells , Carrageenan/toxicity , Cell Line , Cricetinae , Cyclooxygenase 1 , Cyclooxygenase 2 , Cyclooxygenase 2 Inhibitors , Cyclooxygenase Inhibitors/chemistry , Cyclooxygenase Inhibitors/pharmacology , Cyclooxygenase Inhibitors/toxicity , Cyclopentanes/chemistry , Cyclopentanes/pharmacology , Cyclopentanes/toxicity , Digestive System/drug effects , Edema/chemically induced , Edema/drug therapy , Female , Fever/drug therapy , Humans , Hyperalgesia/drug therapy , Male , Membrane Proteins , Microsomes/enzymology , Rats , Rats, Inbred Lew , Rats, Sprague-Dawley , Structure-Activity Relationship , Sulfones/chemistry , Sulfones/pharmacology , Sulfones/toxicity , TransfectionABSTRACT
Comparative computer modeling of the X-ray crystal structures of cyclooxygenase isoforms COX-1 and COX-2 has led to the design of COX-2 selectivity into the nonselective inhibitor flurbiprofen. The COX-2 modeling was based on a postulated binding mode for flurbiprofen and took advantage of a small alcove in the COX-2 active site created by different positions of the Leu384 sidechain between COX-1 and COX-2. The design hypothesis was tested by synthesis and biological assay of a series of flurbiprofen analogs, culminating in the discovery of several inhibitors having up to 78-fold selectivity for COX-2 over COX-1.
Subject(s)
Cyclooxygenase Inhibitors/metabolism , Flurbiprofen/metabolism , Isoenzymes/metabolism , Prostaglandin-Endoperoxide Synthases/metabolism , Binding Sites , Crystallography, X-Ray , Cyclooxygenase 2 , Cyclooxygenase 2 Inhibitors , Cyclooxygenase Inhibitors/chemistry , Drug Design , Flurbiprofen/analogs & derivatives , Flurbiprofen/chemistry , Humans , Membrane Proteins , Molecular StructureABSTRACT
Substituted heterocyclic analogs in the Flosulide class were investigated as potential selective cyclooxygenase-2 inhibitors. 6-(4-Ethyl-2-thiazolylthio)-5-methanesulfonamido-3H-isobe nzofuran-1-one 14 was found to be the optimal compound in the series with superior in vitro and in vivo activities.
