Rho/Rho-kinase pathway contributes to C-reactive protein-induced plasminogen activator inhibitor-1 expression in endothelial cells.
OBJECTIVE
Rho/Rho-kinase pathway plays pivotal roles in cardiovascular diseases including arteriosclerosis and hypertension. Recently it has become evident that C-reactive protein (CRP), a powerful marker for cardiovascular events, has direct proatherothrombotic effects on vascular cells. However, its molecular mechanism has not been fully investigated. We examined the involvement of Rho/Rho-kinase signaling in CRP-induced plasminogen activator inhibitor-1 (PAI-1) expression in bovine aortic endothelial cells (BAECs).


RESULTS
PAI-1 expression was determined by Western blotting. RhoA activation was determined by an affinity pull-down assay using Rho-binding fragment of rhotekin. NF-kappaB activity was determined using the luciferase reporter gene. Incubation of BAECs with human recombinant CRP (> or =25 microg/mL) induced a significant increase in PAI-1 expression. Stimulation of BAECs with CRP significantly increased RhoA activation. Pretreatment with TAT-C3 (a membrane-permeable RhoA inhibitor) and Y-27632 (Rho-kinase inhibitor) significantly inhibited CRP-induced PAI-1 expression. NF-kappaB activity was markedly enhanced by CRP and pretreatment with Y-27632 inhibited its activation. Parthenolide, SN50, and BAY 11-7082 (NF-kappaB inhibitors) significantly blocked CRP-mediated PAI-1 expression.


CONCLUSIONS
These data suggested that CRP activates Rho/Rho-kinase signaling, which in turn activates NF-kappaB activity, resulting in PAI-1 expression in BAEC. These observations provide evidence for the possible involvement of Rho/Rho-kinase signaling in CRP-induced atherothrombogenesis.
Nakakuki
Tetsuya
T
Department of Cardiology, Mie University Graduate School of Medicine, 2-174, Edobashi, Tsu, Mie 514-8507, Japan.
Ito
Masaaki
M
Iwasaki
Hitoshi
H
Kureishi
Yasuko
Y
Okamoto
Ryuji
R
Moriki
Nobuyuki
N
Kongo
Mariko
M
Kato
Shinya
S
Yamada
Norikazu
N
Isaka
Naoki
N
Nakano
Takeshi
T
D000818:Animals; D001011:Aorta / Q000166:cytology; D050197:Atherosclerosis / Q000378:metabolism* / Q000503:physiopathology; D002097:C-Reactive Protein / Q000378:metabolism*; D002417:Cattle; D002478:Cells, Cultured; D004730:Endothelium, Vascular / Q000166:cytology / Q000201:enzymology*; D047908:Intracellular Signaling Peptides and Proteins; D016328:NF-kappa B / Q000037:antagonists & inhibitors / Q000378:metabolism; D017395:Plasminogen Activator Inhibitor 1 / Q000235:genetics / Q000378:metabolism*; D017346:Protein Serine-Threonine Kinases / Q000037:antagonists & inhibitors / Q000378:metabolism*; D015398:Signal Transduction / Q000502:physiology; D013927:Thrombosis / Q000378:metabolism; D014158:Transcription, Genetic / Q000502:physiology; D054460:rho-Associated Kinases; D020742:rhoA GTP-Binding Protein / Q000037:antagonists & inhibitors / Q000378:metabolism*
D047908:Intracellular Signaling Peptides and Proteins; D016328:NF-kappa B; D017395:Plasminogen Activator Inhibitor 1; D002097:C-Reactive Protein; D017346:Protein Serine-Threonine Kinases; D054460:rho-Associated Kinases; D020742:rhoA GTP-Binding Protein