Vascular hypertrophy and hypertension caused by transgenic overexpression of profilin 1

J Biol Chem. 2007 Dec 28;282(52):37632-9. doi: 10.1074/jbc.M703227200. Epub 2007 Oct 16.

Abstract

We have overexpressed either the cDNA of human profilin 1 or expressed the mutant (88R/L) in the blood vessels of transgenic FVB/N mice. Reverse transcription-PCR indicated selective overexpression of profilin 1 and 88R/L in vascular smooth muscle cells. Polyproline binding showed increased profilin 1 and 88R/L proteins in transgenic mice compared with control (~30%, p < 0.05). Rhodamine-phalloidin staining revealed increase stress fiber formation in vascular smooth muscle cells of profilin 1 compared with 88R/L and control. Hematoxylin and eosin staining showed clear signs of vascular hypertrophy in the aorta of profilin 1 mice versus 88R/L and control. However, there were no differences between 88R/L and control mice. Western blotting confirmed the activation of the hypertrophic signaling cascades in aortas of profilin 1 mice. Phospho-ERK1/2 was significantly higher in profilin 1 than 88R/L and control (512.3 and 361.7%, respectively, p < 0.05). Profilin 1 mice had significant increases in phospho-JNK as compared with 88R/L and control (371.4 and 346%, respectively, p < 0.05). However, there were no differences between 88R/L and control mice in both kinases. There was a significant increase in ROCK II kinase in the aorta of profilin 1 mice compared with controls (>400%, p < 0.05). Tail cuff and circadian monitoring of blood pressure showed significant increases in systolic and mean arterial blood pressures of profilin 1 mice starting at age 6 months compared with controls (~25 mm Hg, p < 0.05). These results suggest that increased actin polymerization in blood vessels triggers activation of the hypertrophic signaling cascades and results in elevation of blood pressure at advanced age.

MeSH terms

  • Actins / chemistry
  • Animals
  • Aorta / metabolism
  • Aortic Valve / cytology
  • Blood Pressure
  • Gene Expression Regulation*
  • Hypertension / genetics*
  • Hypertrophy / genetics*
  • MAP Kinase Signaling System
  • Mice
  • Mice, Transgenic
  • Mitogen-Activated Protein Kinase 1 / metabolism
  • Mitogen-Activated Protein Kinase 3 / metabolism
  • Models, Biological
  • Myocytes, Smooth Muscle / cytology
  • Profilins / biosynthesis*
  • Profilins / genetics*
  • Signal Transduction

Substances

  • Actins
  • Profilins
  • Mitogen-Activated Protein Kinase 1
  • Mitogen-Activated Protein Kinase 3