TRPV2 is critical for the maintenance of cardiac structure and function in mice

Nat Commun. 2014 May 29:5:3932. doi: 10.1038/ncomms4932.

Abstract

The heart has a dynamic compensatory mechanism for haemodynamic stress. However, the molecular details of how mechanical forces are transduced in the heart are unclear. Here we show that the transient receptor potential, vanilloid family type 2 (TRPV2) cation channel is critical for the maintenance of cardiac structure and function. Within 4 days of eliminating TRPV2 from hearts of the adult mice, cardiac function declines severely, with disorganization of the intercalated discs that support mechanical coupling with neighbouring myocytes and myocardial conduction defects. After 9 days, cell shortening and Ca(2+) handling by single myocytes are impaired in TRPV2-deficient hearts. TRPV2-deficient neonatal cardiomyocytes form no intercalated discs and show no extracellular Ca(2+)-dependent intracellular Ca(2+) increase and insulin-like growth factor (IGF-1) secretion in response to stretch stimulation. We further demonstrate that IGF-1 receptor/PI3K/Akt pathway signalling is significantly downregulated in TRPV2-deficient hearts, and that IGF-1 administration partially prevents chamber dilation and impairment in cardiac pump function in these hearts. Our results improve our understanding of the molecular processes underlying the maintenance of cardiac structure and function.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Animals
  • Calcium / metabolism
  • Calcium Channels / genetics*
  • Calcium Channels / metabolism
  • Gene Knockdown Techniques
  • Heart*
  • Insulin-Like Growth Factor I / metabolism*
  • Mice
  • Myocardial Contraction
  • Myocardium / metabolism*
  • Myocardium / pathology
  • Myocytes, Cardiac / metabolism*
  • Myocytes, Cardiac / pathology
  • Phosphatidylinositol 3-Kinases / metabolism*
  • Proto-Oncogene Proteins c-akt / metabolism*
  • Receptor, IGF Type 1 / metabolism*
  • Signal Transduction / genetics
  • TRPV Cation Channels / genetics*
  • TRPV Cation Channels / metabolism

Substances

  • Calcium Channels
  • TRPV Cation Channels
  • Trpv2 protein, mouse
  • Insulin-Like Growth Factor I
  • Phosphatidylinositol 3-Kinases
  • Receptor, IGF Type 1
  • Proto-Oncogene Proteins c-akt
  • Calcium