Cross-interactions of two p38 mitogen-activated protein (MAP) kinase inhibitors and two cholecystokinin (CCK) receptor antagonists with the CCK1 receptor and p38 MAP kinase.
Although SB202190 and SB203580 are described as specific p38 MAP kinase inhibitors, several reports have indicated that other enzymes are also sensitive to SB203580. Using a pharmacological approach, we report for the first time that compounds SB202190 and SB203580 were able to directly and selectively interact with a G-protein-coupled receptor, namely the cholecystokinin receptor subtype CCK1, but not with the CCK2 receptor. We demonstrated that these compounds were non-competitive antagonists of the CCK1 receptor at concentrations typically used to inhibit protein kinases. By chimeric construction of the CCK2 receptor, we determined the involvement of two CCK1 receptor intracellular loops in the binding of SB202190 and SB203580. We also showed that two CCK antagonists, L364,718 and L365,260, were able to regulate p38 mitogen-activated protein (MAP) kinase activity. Using a reporter gene strategy and immunoblotting experiments, we demonstrated that both CCK antagonists inhibited selectively the enzymatic activity of p38 MAP kinase. Kinase assays suggested that this inhibition resulted from a direct interaction with both CCK antagonists. Molecular modeling simulations suggested that this interaction occurs in the ATP binding pocket of p38 MAP kinase. These results suggest that SB202190 and SB203580 bind to the CCK1 receptor and, as such, these compounds should be used with caution in models that express this receptor. We also found that L364,718 and L365,260, two CCK receptor antagonists, directly interacted with p38 MAP kinase and inhibited its activity. These findings suggest that the CCK1 receptor shares structural analogies with the p38 MAP kinase ATP binding site. They open the way to potential design of either a new family of MAP kinase inhibitors from CCK1 receptor ligand structures or new CCK1 receptor ligands based on p38 MAP kinase inhibitor structures.
Morel
Caroline
C
Laboratoire des Aminoacides, Peptides, et Protéines, CNRS Unite Mixte de Recherche-5810, UMI et UMII, UFR Pharmacie, 15, Avenue Charles Flahault, 34093 Montpellier Cedex 5, France.
Ibarz
Géraldine
G
Oiry
Catherine
C
Carnazzi
Eric
E
Bergé
Gilbert
G
Gagne
Didier
D
Galleyrand
Jean-Claude
JC
Martinez
Jean
J
D000255:Adenosine Triphosphate / Q000737:chemistry; D000818:Animals; D001570:Benzodiazepinones / Q000494:pharmacology; D001665:Binding Sites; D015153:Blotting, Western; D019556:COS Cells; D020109:Devazepide / Q000494:pharmacology; D004305:Dose-Response Relationship, Drug; D004791:Enzyme Inhibitors / Q000494:pharmacology*; D017930:Genes, Reporter; D006727:Hormone Antagonists / Q000494:pharmacology; D007093:Imidazoles / Q000494:pharmacology; D015151:Immunoblotting; D007295:Inositol Phosphates / Q000737:chemistry; D007700:Kinetics; D008024:Ligands; D020935:MAP Kinase Signaling System; D008956:Models, Chemical; D008958:Models, Molecular; D010671:Phenylurea Compounds / Q000494:pharmacology; D011485:Protein Binding; D011487:Protein Conformation; D011725:Pyridines / Q000494:pharmacology; D051381:Rats; D043886:Receptor, Cholecystokinin A / Q000378:metabolism; D011949:Receptors, Cholecystokinin / Q000037:antagonists & inhibitors*; D015398:Signal Transduction; D013997:Time Factors; D014162:Transfection; D048051:p38 Mitogen-Activated Protein Kinases / Q000037:antagonists & inhibitors* / Q000378:metabolism
D001570:Benzodiazepinones; D004791:Enzyme Inhibitors; D006727:Hormone Antagonists; D007093:Imidazoles; D007295:Inositol Phosphates; D008024:Ligands; D010671:Phenylurea Compounds; D011725:Pyridines; D043886:Receptor, Cholecystokinin A; D011949:Receptors, Cholecystokinin; C058121:L 365260; D000255:Adenosine Triphosphate; D048051:p38 Mitogen-Activated Protein Kinases; D020109:Devazepide; C093642:SB 203580; C090942:4-(4-fluorophenyl)-2-(4-hydroxyphenyl)-5-(4-pyridyl)imidazole