Flow-dependent epigenetic DNA methylation regulates endothelial gene expression and atherosclerosis

J Clin Invest. 2014 Jul;124(7):3187-99. doi: 10.1172/JCI74792. Epub 2014 May 27.

Abstract

In atherosclerosis, plaques preferentially develop in arterial regions of disturbed blood flow (d-flow), which alters endothelial gene expression and function. Here, we determined that d-flow regulates genome-wide DNA methylation patterns in a DNA methyltransferase-dependent (DNMT-dependent) manner. Induction of d-flow by partial carotid ligation surgery in a murine model induced DNMT1 in arterial endothelium. In cultured endothelial cells, DNMT1 was enhanced by oscillatory shear stress (OS), and reduction of DNMT with either the inhibitor 5-aza-2'-deoxycytidine (5Aza) or siRNA markedly reduced OS-induced endothelial inflammation. Moreover, administration of 5Aza reduced lesion formation in 2 mouse models of atherosclerosis. Using both reduced representation bisulfite sequencing (RRBS) and microarray, we determined that d-flow in the carotid artery resulted in hypermethylation within the promoters of 11 mechanosensitive genes and that 5Aza treatment restored normal methylation patterns. Of the identified genes, HoxA5 and Klf3 encode transcription factors that contain cAMP response elements, suggesting that the methylation status of these loci could serve as a mechanosensitive master switch in gene expression. Together, our results demonstrate that d-flow controls epigenomic DNA methylation patterns in a DNMT-dependent manner, which in turn alters endothelial gene expression and induces atherosclerosis.

Publication types

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

MeSH terms

  • Animals
  • Apolipoproteins E / deficiency
  • Apolipoproteins E / genetics
  • Atherosclerosis / genetics*
  • Atherosclerosis / metabolism*
  • Atherosclerosis / physiopathology
  • Azacitidine / analogs & derivatives
  • Azacitidine / pharmacology
  • DNA (Cytosine-5-)-Methyltransferase 1
  • DNA (Cytosine-5-)-Methyltransferases / antagonists & inhibitors
  • DNA (Cytosine-5-)-Methyltransferases / genetics
  • DNA (Cytosine-5-)-Methyltransferases / metabolism
  • DNA Methylation*
  • Decitabine
  • Disease Models, Animal
  • Endothelial Cells / drug effects
  • Endothelial Cells / metabolism
  • Epigenesis, Genetic
  • Gene Expression Regulation
  • Homeodomain Proteins / genetics
  • Human Umbilical Vein Endothelial Cells
  • Humans
  • Kruppel-Like Transcription Factors / genetics
  • Mice
  • Mice, Inbred C57BL
  • Mice, Knockout
  • Phosphoproteins / genetics
  • Plaque, Atherosclerotic / etiology
  • Plaque, Atherosclerotic / genetics
  • Plaque, Atherosclerotic / physiopathology
  • Promoter Regions, Genetic
  • RNA, Messenger / genetics
  • RNA, Messenger / metabolism
  • Regional Blood Flow
  • Stress, Mechanical
  • Transcription Factors

Substances

  • Apolipoproteins E
  • Homeodomain Proteins
  • Hoxa5 protein, mouse
  • Klf3 protein, mouse
  • Kruppel-Like Transcription Factors
  • Phosphoproteins
  • RNA, Messenger
  • Transcription Factors
  • Decitabine
  • DNA (Cytosine-5-)-Methyltransferase 1
  • DNA (Cytosine-5-)-Methyltransferases
  • DNMT1 protein, human
  • Dnmt1 protein, mouse
  • Azacitidine