title: Bradykinin B1 receptor blocks PDGF-induced mitogenesis by prolonging ERK activation and increasing p27Kip1.
abstract: The mechanism by which the bradykinin B1 receptor (B1R) inhibits platelet-derived growth factor (PDGF)-stimulated proliferation was investigated in cultured rat mesenteric arterial smooth muscle cells. The B1R agonist des-Arg9-bradykinin (DABK) was found to inhibit PDGF-mediated activation of the cyclin E-cyclin-dependent kinase 2 (Cdk2) complex and to prevent hyperphosphorylation of retinoblastoma protein. DABK did not inhibit upregulation of cyclin E expression but increased expression of the Cdk2 inhibitor p27Kip1 and the association of p27Kip1 with the cyclin E-Cdk2 complex. In addition, DABK inhibited the PDGF-stimulated expression of cyclin D that would otherwise siphon p27Kip1 away from inhibition of cyclin E-Cdk2. The signaling mechanism by which DABK regulated p27Kip1 was explored. DABK was found to stimulate the activity of mitogen-activated protein kinase kinase (MEK) and extracellular signal-regulated kinase (ERK) and to prolong activation of MEK and ERK by PDGF. Inhibition of ERK activation with the MEK inhibitors PD-98059 and U-0126 as well as the Src family kinase inhibitor PP2 completely blocked the effect of DABK to increase p27Kip1 and partially reversed the DABK-mediated inhibition of PDGF-stimulated proliferation. These studies demonstrate that the B1R inhibits PDGF-stimulated mitogenesis in part by prolonged activation of ERK leading to increased expression of p27Kip1.
authors.affiliation: Division of Nephrology, Department of Medicine, Department of Veterans Affairs Medical Center and University of Iowa College of Medicine, Iowa City, Iowa 52242-1081, USA. bradley-dixon@uiowa.edu
authors.forename: Bradley S
authors.initials: BS
authors.lastname: Dixon
authors.forename: David
authors.initials: D
authors.lastname: Evanoff
authors.forename: Wei B
authors.initials: WB
authors.lastname: Fang
authors.forename: Michael J
authors.initials: MJ
authors.lastname: Dennis
mesh_terms: D000818:Animals; D001920:Bradykinin / Q000031:analogs & derivatives* / Q000494:pharmacology; D042846:CDC2-CDC28 Kinases; D018797:Cell Cycle Proteins / Q000378:metabolism*; D002478:Cells, Cultured; D019925:Cyclin A / Q000378:metabolism; D019927:Cyclin E / Q000378:metabolism; D051357:Cyclin-Dependent Kinase 2; D050760:Cyclin-Dependent Kinase Inhibitor p27; D018844:Cyclin-Dependent Kinases / Q000037:antagonists & inhibitors / Q000378:metabolism; D004789:Enzyme Activation / Q000502:physiology; D004791:Enzyme Inhibitors / Q000494:pharmacology; D016193:G1 Phase; D008297:Male; D020929:Mitogen-Activated Protein Kinase Kinases / Q000037:antagonists & inhibitors / Q000378:metabolism; D020928:Mitogen-Activated Protein Kinases / Q000378:metabolism*; D008938:Mitosis / Q000502:physiology*; D010982:Platelet-Derived Growth Factor / Q000494:pharmacology*; D017346:Protein Serine-Threonine Kinases / Q000037:antagonists & inhibitors / Q000378:metabolism; D051381:Rats; D017207:Rats, Sprague-Dawley; D043783:Receptor, Bradykinin B1; D018002:Receptors, Bradykinin / Q000502:physiology*; D013997:Time Factors; D025521:Tumor Suppressor Proteins / Q000378:metabolism*; D019061:src-Family Kinases / Q000037:antagonists & inhibitors
chemical_list: C493962:Cdkn1b protein, rat; D018797:Cell Cycle Proteins; D019925:Cyclin A; D019927:Cyclin E; D004791:Enzyme Inhibitors; D010982:Platelet-Derived Growth Factor; D043783:Receptor, Bradykinin B1; D018002:Receptors, Bradykinin; D025521:Tumor Suppressor Proteins; D050760:Cyclin-Dependent Kinase Inhibitor p27; C024626:bradykinin, des-Arg(9)-; D019061:src-Family Kinases; D017346:Protein Serine-Threonine Kinases; D042846:CDC2-CDC28 Kinases; C495892:Cdk2 protein, rat; D051357:Cyclin-Dependent Kinase 2; D018844:Cyclin-Dependent Kinases; D020928:Mitogen-Activated Protein Kinases; D020929:Mitogen-Activated Protein Kinase Kinases; D001920:Bradykinin