Simvastatin Increases Fibulin-2 Expression in Human Coronary Artery Smooth Muscle Cells via RhoA/Rho-Kinase Signaling Pathway Inhibition

PLoS One. 2015 Jul 24;10(7):e0133875. doi: 10.1371/journal.pone.0133875. eCollection 2015.

Abstract

The composition and structure of the extracellular matrix (ECM) in the vascular wall and in the atherosclerotic plaque are important factors that determine plaque stability. Statins can stabilize atherosclerotic plaques by modulating ECM protein expression. Fibulins are important components of the ECM. We evaluated the in vitro effect of simvastatin on the expression of fibulin-1, -2, -4 and -5 in human coronary artery smooth muscle cells (SMCs) and the mechanisms involved. Cells were incubated with simvastatin (0.05-1 μM), mevalonate (100 and 200 μM), geranylgeranyl pyrophosphate (GGPP) (15 μM), farnesyl pyrophosphate (FPP) (15 μM), the Rho kinase (ROCK) inhibitor Y-27632 (15 and 20 μM), the Rac-1 inhibitor (another member of Rho family) NSC23766 (100 μM), arachidonic acid (a RhoA/ROCK activator, 25-100 μM) and other fatty acids that are not activators of RhoA/ROCK (25-100 μM). Gene expression was analyzed by quantitative real-time PCR, and fibulin protein levels were analyzed by western blotting and ELISA. Simvastatin induced a significant increase in mRNA and protein levels of fibulin-2 at 24 hours of incubation (p<0.05), but it did not affect fibulin-1, -4, and -5 expression. Mevalonate and GGPP were able to reverse simvastatin's effect, while FPP did not. In addition, Y-27632, but not NSC23766, significantly increased fibulin-2 expression. Furthermore, activation of the RhoA/ROCK pathway with arachidonic acid decreased fibulin-2 mRNA. Simvastatin increased mRNA levels and protein expression of the ECM protein fibulin-2 through a RhoA and Rho-Kinase-mediated pathway. This increase could affect the composition and structure of the ECM.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Calcium-Binding Proteins / metabolism*
  • Cell Line
  • Coronary Vessels / drug effects*
  • Coronary Vessels / metabolism
  • Extracellular Matrix Proteins / metabolism*
  • Humans
  • Hydroxymethylglutaryl-CoA Reductase Inhibitors / pharmacology
  • Muscle, Smooth, Vascular / drug effects*
  • Muscle, Smooth, Vascular / metabolism
  • Myocytes, Smooth Muscle / drug effects*
  • Myocytes, Smooth Muscle / metabolism
  • Signal Transduction / drug effects*
  • Simvastatin / pharmacology*
  • rho-Associated Kinases / metabolism*
  • rhoA GTP-Binding Protein / metabolism*

Substances

  • Calcium-Binding Proteins
  • Extracellular Matrix Proteins
  • Hydroxymethylglutaryl-CoA Reductase Inhibitors
  • fibulin 2
  • Simvastatin
  • rho-Associated Kinases
  • rhoA GTP-Binding Protein

Grants and funding

This work was supported by a grant from the Fondo de Investigación Sanitaria, Instituto de Salud Carlos III, [FIS PI030786]; and Centro de Investigación Biomédica de Diabetes y Enfermedades Metabólicas Asociadas (CIBERDEM).