Effect of simvastatin on Kruppel-like factor2, endothelial nitric oxide synthase and thrombomodulin expression in endothelial cells under shear stress.
OBJECTIVE
Statins (3-hydroxy-3-methylglutaryl coenzyme A reductase inhibitors) and fluid wall shear stress have been reported to modulate the expression of genes related to inflammation, blood coagulation, thrombosis, and vascular constriction in cultured endothelial cells. In this study, we investigated the combined effect of laminar shear stress (LSS) and statins on endothelial cell gene expression.


METHODS
Kruppel-like factor 2 (KLF2), endothelial nitric oxide synthase (eNOS), and thrombomodulin (TM) mRNA and protein expression were evaluated in human abdominal aortic endothelial cells (HAAEC) treated with simvastatin (0.1, 1 or 10 microM) at various levels of LSS (0, 1.25, 12.5 or 25 dynes/cm(2)).


RESULTS
As expected, simvastatin and LSS separately enhanced KLF2, eNOS, and TM mRNA expressions. The combination of simvastatin and LSS resulted in significantly higher mRNA levels of all three genes compared to cells treated with LSS only. The highest KLF2, eNOS, and TM mRNA levels were detected at 10 microM simvastatin and 25 dynes/cm(2). Under these conditions, eNOS and TM protein levels were also elevated. Combining LSS and simvastatin produced an overall additive increase in KLF2, eNOS, and TM mRNA. Treatment of the endothelial cells with 10 microM simvastatin and 200 microM mevalonate completely eliminated the effect of simvastatin.


CONCLUSIONS
Our results suggest an additive increase in KLF2, eNOS, and TM expressions when simvastatin and LSS are combined. These results may help to explain the proposed non-lipid lowering benefits of statins observed in the clinic.
Rossi
Joanna
J
Dept. of Chemical Engineering, McGill University, 3610 University Street, Montreal, QC, Canada.
Rouleau
Leonie
L
Tardif
Jean-Claude
JC
Leask
Richard L
RL
D001012:Aorta, Abdominal / Q000166:cytology / Q000187:drug effects / Q000378:metabolism; D002478:Cells, Cultured; D004305:Dose-Response Relationship, Drug; D004730:Endothelium, Vascular / Q000166:cytology / Q000187:drug effects / Q000378:metabolism; D005786:Gene Expression Regulation / Q000187:drug effects; D006801:Humans; D019161:Hydroxymethylglutaryl-CoA Reductase Inhibitors / Q000008:administration & dosage / Q000494:pharmacology*; D051741:Kruppel-Like Transcription Factors / Q000187:drug effects* / Q000235:genetics / Q000378:metabolism; D052250:Nitric Oxide Synthase Type III / Q000187:drug effects* / Q000235:genetics / Q000378:metabolism; D012333:RNA, Messenger / Q000378:metabolism; D019821:Simvastatin / Q000008:administration & dosage / Q000494:pharmacology*; D013314:Stress, Mechanical; D018180:Thrombomodulin / Q000187:drug effects* / Q000235:genetics
D019161:Hydroxymethylglutaryl-CoA Reductase Inhibitors; C096161:KLF2 protein, human; D051741:Kruppel-Like Transcription Factors; D012333:RNA, Messenger; D018180:Thrombomodulin; D019821:Simvastatin; D052250:Nitric Oxide Synthase Type III