FAK regulates cardiomyocyte survival following ischemia/reperfusion

J Mol Cell Cardiol. 2009 Feb;46(2):241-8. doi: 10.1016/j.yjmcc.2008.10.017. Epub 2008 Nov 5.

Abstract

Myocyte apoptosis is central to myocardial dysfunction following ischemia/reperfusion (I/R) and during the transition from hypertrophy to heart failure. Focal adhesion kinase (FAK), a non-receptor tyrosine kinase regulates adhesion-dependent survival signals and unopposed FAK activation has been linked to tumor development. We previously showed that conditional myocyte-specific deletion of FAK (MFKO) in the adult heart did not affect basal cardiomyocyte survival or cardiac function but led to dilated cardiomyopathy and heart failure following pressure overload. In the present study, we sought to determine if FAK functions to limit stress-induced cardiomyocyte apoptosis. We reasoned that (I/R), which stimulates robust apoptotic cell death, might uncover an important cardioprotective function for FAK. We found that depletion of FAK markedly exacerbates hypoxia/re-oxygenation-induced cardiomyocyte cell death in vitro. Moreover, deletion of FAK in the adult myocardium resulted in significant increases in I/R-induced infarct size and cardiomyocyte apoptosis with a concomitant reduction in left ventricular function. Finally, our results suggest that NF-kappaB signaling may play a key role in modulating FAK-dependent cardioprotection, since FAK inactivation blunted activation of the NF-kappaB survival signaling pathway and reduced levels of the NF-kappaB target genes, Bcl2 and Bcl-xl. Since the toggling between pro-survival and pro-apoptotic signals remains central to preventing irreversible damage to the heart, we conclude that targeted FAK activation may be beneficial for protecting stress-dependent cardiac remodeling.

Publication types

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

MeSH terms

  • Animals
  • Apoptosis / genetics
  • Apoptosis / physiology
  • Blotting, Western
  • Focal Adhesion Kinase 1 / genetics
  • Focal Adhesion Kinase 1 / physiology*
  • Focal Adhesion Protein-Tyrosine Kinases / genetics
  • Focal Adhesion Protein-Tyrosine Kinases / physiology*
  • Mice
  • Mice, Mutant Strains
  • Myocardial Reperfusion Injury / genetics
  • Myocardial Reperfusion Injury / prevention & control*
  • Myocytes, Cardiac / cytology*
  • Myocytes, Cardiac / metabolism*
  • NF-kappa B / genetics
  • NF-kappa B / physiology
  • Reperfusion Injury / genetics
  • Reperfusion Injury / prevention & control*
  • Reverse Transcriptase Polymerase Chain Reaction
  • Signal Transduction / genetics
  • Signal Transduction / physiology

Substances

  • NF-kappa B
  • Focal Adhesion Kinase 1
  • Focal Adhesion Protein-Tyrosine Kinases