Class I HDACs regulate angiotensin II-dependent cardiac fibrosis via fibroblasts and circulating fibrocytes

J Mol Cell Cardiol. 2014 Feb:67:112-25. doi: 10.1016/j.yjmcc.2013.12.013. Epub 2013 Dec 26.


Fibrosis, which is defined as excessive accumulation of fibrous connective tissue, contributes to the pathogenesis of numerous diseases involving diverse organ systems. Cardiac fibrosis predisposes individuals to myocardial ischemia, arrhythmias and sudden death, and is commonly associated with diastolic dysfunction. Histone deacetylase (HDAC) inhibitors block cardiac fibrosis in pre-clinical models of heart failure. However, which HDAC isoforms govern cardiac fibrosis, and the mechanisms by which they do so, remains unclear. Here, we show that selective inhibition of class I HDACs potently suppresses angiotensin II (Ang II)-mediated cardiac fibrosis by targeting two key effector cell populations, cardiac fibroblasts and bone marrow-derived fibrocytes. Class I HDAC inhibition blocks cardiac fibroblast cell cycle progression through derepression of the genes encoding the cyclin-dependent kinase (CDK) inhibitors, p15 and p57. In contrast, class I HDAC inhibitors block agonist-dependent differentiation of fibrocytes through a mechanism involving repression of ERK1/2 signaling. These findings define novel roles for class I HDACs in the control of pathological cardiac fibrosis. Furthermore, since fibrocytes have been implicated in the pathogenesis of a variety of human diseases, including heart, lung and kidney failure, our results suggest broad utility for isoform-selective HDAC inhibitors as anti-fibrotic agents that function, in part, by targeting these circulating mesenchymal cells.

Keywords: Fibroblast; Fibrocyte; Fibrosis; Histone deacetylase.

Publication types

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

MeSH terms

  • Angiotensin II / metabolism*
  • Animals
  • Cell Cycle / drug effects
  • Cell Differentiation
  • Fibroblasts / drug effects*
  • Fibroblasts / metabolism
  • Fibrosis / drug therapy
  • Fibrosis / physiopathology*
  • Flow Cytometry
  • Histone Deacetylase Inhibitors / pharmacology*
  • Humans
  • Immunoblotting
  • Male
  • Mice
  • Mice, Inbred C57BL
  • Polymerase Chain Reaction
  • Protein Isoforms / pharmacology


  • Histone Deacetylase Inhibitors
  • Protein Isoforms
  • Angiotensin II