title: Nebivolol inhibits human aortic smooth muscle cell growth: effects on cell cycle regulatory proteins.
abstract: An enhanced vasoconstriction and vascular smooth muscle cell proliferation are involved in pathogenesis of hypertension. Beta3-blockers are effective for treatment of hypertensive patients. Recently the new beta1-receptor blocker nebivolol showed a different hemodynamic profile from those of other classic beta-blockers. In this study we hypothesized that nebivolol may also have different effects on smooth muscle cell proliferation compared with other beta-blockers such as atenolol. Human aortic smooth muscle cells (SMCs) were cultured, and cell growth was determined by increase in cell number. Growth-signaling molecules such as mitogen-activated protein kinase (p42mapk) and S6-kinase (p70S6K) and cell-cycle regulatory proteins (i.e., Cdk2, p27Kip1, and pRb) were analyzed by immunoblotting. In cultured human aortic SMCs, cell number was markedly increased in response to 5% fetal calf serum (FCS) over 6 days (87 +/- 11 x 10(3)/well), which was inhibited by nebivolol (10(-8)-10(-5) M; 25 +/- 2 x 10(3)/well; n = 6; p < 0.05), but not by atenolol. 5% FCS activated p42mapk, S6K, and Cdk2, but downregulated p27Kip1 and hyperphosphorylated pRb. Nebivolol prevented Cdk2 activation without influencing p42mapk, S6K, pRB, and p27Kip1. Thus, the new beta1-blocker nebivolol exhibits antiproliferative effect on human SMC through inactivation of Cdk2. This effect of nebivolol may have advantages over other beta-blockers in treatment of patients with cardiovascular disease.
authors.affiliation: Cardiovascular Research, Institute of Physiology, University Zürich-Irchel, Switzerland.
authors.forename: D E
authors.initials: DE
authors.lastname: André
authors.forename: U
authors.initials: U
authors.lastname: Arnet
authors.forename: Z
authors.initials: Z
authors.lastname: Yang
authors.forename: T F
authors.initials: TF
authors.lastname: Lüscher
mesh_terms: D000319:Adrenergic beta-Antagonists / Q000494:pharmacology*; D001011:Aorta / Q000166:cytology; D001262:Atenolol / Q000494:pharmacology; D001578:Benzopyrans / Q000494:pharmacology*; D042846:CDC2-CDC28 Kinases; D018797:Cell Cycle Proteins / Q000187:drug effects / Q000378:metabolism; D002455:Cell Division / Q000187:drug effects*; D002478:Cells, Cultured; D051357:Cyclin-Dependent Kinase 2; D050760:Cyclin-Dependent Kinase Inhibitor p27; D018844:Cyclin-Dependent Kinases / Q000378:metabolism; D004789:Enzyme Activation / Q000187:drug effects; D004983:Ethanolamines / Q000494:pharmacology*; D006801:Humans; D008869:Microtubule-Associated Proteins / Q000378:metabolism; D019950:Mitogen-Activated Protein Kinase 1 / Q000378:metabolism; D009131:Muscle, Smooth, Vascular / Q000166:cytology / Q000187:drug effects* / Q000378:metabolism; D000068577:Nebivolol; D017346:Protein Serine-Threonine Kinases / Q000378:metabolism; D016160:Retinoblastoma Protein / Q000378:metabolism; D019893:Ribosomal Protein S6 Kinases / Q000378:metabolism; D013997:Time Factors; D025521:Tumor Suppressor Proteins
chemical_list: D000319:Adrenergic beta-Antagonists; D001578:Benzopyrans; D018797:Cell Cycle Proteins; D004983:Ethanolamines; D008869:Microtubule-Associated Proteins; D016160:Retinoblastoma Protein; D025521:Tumor Suppressor Proteins; D000068577:Nebivolol; D050760:Cyclin-Dependent Kinase Inhibitor p27; D001262:Atenolol; D017346:Protein Serine-Threonine Kinases; D019893:Ribosomal Protein S6 Kinases; D042846:CDC2-CDC28 Kinases; C495894:CDK2 protein, human; D051357:Cyclin-Dependent Kinase 2; D018844:Cyclin-Dependent Kinases; D019950:Mitogen-Activated Protein Kinase 1