NOTCH1 regulates matrix gla protein and calcification gene networks in human valve endothelium

J Mol Cell Cardiol. 2015 Jul;84:13-23. doi: 10.1016/j.yjmcc.2015.04.006. Epub 2015 Apr 12.

Abstract

Valvular and vascular calcification are common causes of cardiovascular morbidity and mortality. Developing effective treatments requires understanding the molecular underpinnings of these processes. Shear stress is thought to play a role in inhibiting calcification. Furthermore, NOTCH1 regulates vascular and valvular endothelium, and human mutations in NOTCH1 can cause calcific aortic valve disease. Here, we determined the genome-wide impact of altering shear stress and NOTCH signaling on human aortic valve endothelium. mRNA-sequencing of primary human aortic valve endothelial cells (HAVECs) with or without knockdown of NOTCH1, in the presence or absence of shear stress, revealed NOTCH1-dependency of the atherosclerosis-related gene connexin 40 (GJA5), and numerous repressors of endochondral ossification. Among these, matrix gla protein (MGP) is highly expressed in aortic valve and vasculature, and inhibits soft tissue calcification by sequestering bone morphogenetic proteins (BMPs). Altering NOTCH1 levels affected MGP mRNA and protein in HAVECs. Furthermore, shear stress activated NOTCH signaling and MGP in a NOTCH1-dependent manner. NOTCH1 positively regulated endothelial MGP in vivo through specific binding motifs upstream of MGP. Our studies suggest that shear stress activates NOTCH1 in primary human aortic valve endothelial cells leading to downregulation of osteoblast-like gene networks that play a role in tissue calcification.

Keywords: Matrix gla protein; NOTCH signaling; NOTCH1; Valve calcification; Valve endothelium.

Publication types

  • Research Support, N.I.H., Extramural
  • Research Support, Non-U.S. Gov't

MeSH terms

  • Aortic Valve / pathology*
  • Aortic Valve Stenosis / genetics*
  • Aortic Valve Stenosis / pathology
  • Calcinosis / genetics*
  • Calcinosis / pathology
  • Calcium-Binding Proteins / metabolism*
  • Chromatin Immunoprecipitation
  • Cluster Analysis
  • DNA / metabolism
  • Endothelial Cells / metabolism
  • Endothelium, Vascular / metabolism*
  • Enhancer Elements, Genetic / genetics
  • Extracellular Matrix Proteins / metabolism*
  • Gene Expression Regulation
  • Gene Regulatory Networks*
  • Genome, Human
  • Humans
  • Protein Binding
  • Receptor, Notch1 / metabolism*
  • Rheology
  • Sequence Analysis, RNA
  • Signal Transduction / genetics
  • Stress, Mechanical

Substances

  • Calcium-Binding Proteins
  • Extracellular Matrix Proteins
  • Receptor, Notch1
  • matrix Gla protein
  • DNA

Supplementary concepts

  • Aortic Valve, Calcification of