title: Hmg-CoA reductase inhibitor modulates monocyte-endothelial cell interaction under physiological flow conditions in vitro: involvement of Rho GTPase-dependent mechanism.
abstract: 3-Hydroxy-3-methylglutaryl coenzyme A reductase inhibitors, or statins, have been reported to exert actions independent of their lipid-lowering effects. To critically assess the effects of statins on monocyte-endothelial cell interactions, we used an in vitro model that mimicked physiological flow conditions. Monocytic U937 cells were incubated in the presence of cerivastatin for 48 hours. Adhesive interactions of statin-treated U937 cells were then analyzed by use of activated (interleukin-1beta 10 U/mL, 4 hours) human umbilical vein endothelial cells in an in vitro flow apparatus. Flow cytometric analysis of adhesion molecules and measurement of F-actin content in U937 cells were performed before and after statin treatment. Preincubation with cerivastatin significantly decreased U937 firm adhesion to activated human umbilical vein endothelial cells, whereas U937 rolling was not decreased. Fluorescence-activated cell sorter analysis revealed downregulation of U937 surface expression of CD11a, CD18, and VLA4 after statin treatment. Cerivastatin significantly reduced F-actin content in U937 cells and inhibited RhoA translocation, whereas preincubation with C3 exoenzyme reduced U937 adhesion under flow. Cerivastatin reduces monocyte adhesion to vascular endothelium under physiological flow conditions via downregulation of integrin adhesion molecules and inhibition of actin polymerization via RhoA inactivation. Our findings have important implications for the lipid-independent effects of statins.
authors.affiliation: Department of Applied Genetics, Tokyo Medical and Dental University, Japan. masamgen@tmd.ac.jp
authors.forename: M
authors.initials: M
authors.lastname: Yoshida
authors.forename: T
authors.initials: T
authors.lastname: Sawada
authors.forename: H
authors.initials: H
authors.lastname: Ishii
authors.forename: R E
authors.initials: RE
authors.lastname: Gerszten
authors.forename: A
authors.initials: A
authors.lastname: Rosenzweig
authors.forename: M A
authors.initials: MA
authors.lastname: Gimbrone
authors.forename: Y
authors.initials: Y
authors.lastname: Yasukochi
authors.forename: F
authors.initials: F
authors.lastname: Numano
mesh_terms: D036002:ADP Ribose Transferases / Q000494:pharmacology; D000199:Actins / Q000378:metabolism; D001905:Botulinum Toxins; D002448:Cell Adhesion; D002460:Cell Line; D002462:Cell Membrane / Q000378:metabolism; D002478:Cells, Cultured; D015536:Down-Regulation; D004730:Endothelium, Vascular / Q000187:drug effects / Q000502:physiology*; D006801:Humans; D019161:Hydroxymethylglutaryl-CoA Reductase Inhibitors / Q000494:pharmacology*; D016023:Integrins / Q000378:metabolism; D009000:Monocytes / Q000187:drug effects / Q000502:physiology*; D009154:Mutation; D011108:Polymers / Q000378:metabolism; D021381:Protein Transport; D011725:Pyridines / Q000494:pharmacology*; D020298:U937 Cells; D020742:rhoA GTP-Binding Protein / Q000037:antagonists & inhibitors / Q000235:genetics / Q000502:physiology*
chemical_list: D000199:Actins; D019161:Hydroxymethylglutaryl-CoA Reductase Inhibitors; D016023:Integrins; D011108:Polymers; D011725:Pyridines; C086276:cerivastatin; D036002:ADP Ribose Transferases; C063007:exoenzyme C3, Clostridium botulinum; D001905:Botulinum Toxins; D020742:rhoA GTP-Binding Protein