Mechanical properties of the extracellular matrix alter expression of smooth muscle protein LPP and its partner palladin; relationship to early atherosclerosis and vascular injury

J Muscle Res Cell Motil. 2009;30(1-2):41-55. doi: 10.1007/s10974-009-9173-1. Epub 2009 Feb 10.

Abstract

Lipoma preferred partner (LPP) localizes to focal adhesions/dense bodies, is selectively expressed in smooth muscle cells (SMC) and enhances cell migration. SMCs cultured on denatured collagen or on a rigid substrate, up regulated expression of LPP, its partner palladin, tenascin C (TN-C), phosphorylated focal adhesion kinase (pFAK) and exhibited robust stress fibers. In an endothelial (EC)/SMC hemodynamic flow system, shear stress waveforms mimicking atheroprone flow, applied to the EC layer, significantly decreased expression of SMC LPP and palladin. They were also down regulated with TN-C, in an ApoE murine model of atherosclerosis and with oxidative stress but up regulated in an arterial injury model in response to upstream sequential changes in pFAK, Prx1 and TN-C. In conclusion, expression of LPP and palladin are modulated by a mix of mechanical cues, oxidative stress and substrate composition which translate into their up or down regulation in vessel wall injury and early atherogenesis.

Publication types

  • Research Support, N.I.H., Extramural

MeSH terms

  • Animals
  • Aorta / injuries
  • Aorta / metabolism
  • Apolipoproteins E / genetics
  • Apolipoproteins E / metabolism
  • Atherosclerosis / genetics
  • Atherosclerosis / metabolism*
  • Cell Adhesion
  • Cell Movement
  • Collagen / metabolism
  • Cytoskeletal Proteins / biosynthesis*
  • Cytoskeletal Proteins / metabolism
  • Endothelial Cells / metabolism
  • Extracellular Matrix / metabolism*
  • Focal Adhesion Protein-Tyrosine Kinases / metabolism
  • Humans
  • LIM Domain Proteins
  • Male
  • Mice
  • Mice, Inbred C57BL
  • Mice, Knockout
  • Muscle, Smooth, Vascular / metabolism*
  • Oxidative Stress
  • Phosphoproteins / biosynthesis*
  • Phosphoproteins / metabolism
  • Rats
  • Rats, Sprague-Dawley
  • Shear Strength*
  • Stress Fibers / metabolism
  • Tenascin / metabolism

Substances

  • Apolipoproteins E
  • Cytoskeletal Proteins
  • LIM Domain Proteins
  • LPP protein, human
  • PALLD protein, human
  • Phosphoproteins
  • Tenascin
  • Collagen
  • Focal Adhesion Protein-Tyrosine Kinases