Document Type
Preprint
Publication Date
3-1-2007
Journal / Book Title
Circulation research
Abstract
Substantial evidence suggests that the progressive loss of cardiomyocytes caused by apoptosis significantly contributes to the development of heart failure. β-Adrenergic receptor activation and subsequent persistent phosphodiesterase 3A (PDE3A) downregulation and concomitant inducible cAMP early repressor (ICER) upregulation (PDE3A/ICER feedback loop) has been proposed to play a key role in the pathogenesis of cardiomyocyte apoptosis. In contrast, insulin-like growth factor-1 can activate cell survival pathways, providing protection against cell death and restoring muscle function. In this study, we found that insulin-like growth factor-1 activates extracellular signal-regulated kinase 5 (ERK5) and inhibits PDE3A/ICER feedback loop. Insulin-like growth factor-1 normalized isoproterenol-mediated PDE3A downregulation and ICER upregulation via ERK5/MEF2 activation, and also inhibited isoproterenol-induced myocyte apoptosis. To determine the physiological relevance of ERK5 activation in regulating PDE3A/ICER feedback loop, we investigated the PDE3A/ICER expression and cardiomyocyte apoptosis in transgenic mice with cardiac specific expression of a constitutively active form of mitogen-activated protein (MAP)/extracellular signal-regulated protein kinase (ERK) kinase 5α (MEK5α) (CA-MEK5α-Tg). In wild-type mice, pressure overload- or doxorubicin-induced significant reduction of PDE3A expression and subsequent ICER induction. Cardiac specific expression of CA-MEK5α rescued pressure overload- or doxorubicin-mediated PDE3A downregulation and ICER upregulation and inhibited myocyte apoptosis as well as subsequent cardiac dysfunction in vivo. These data suggest that preventing the feedback loop of PDE3A/ICER by ERK5 activation could inhibit progression of myocyte apoptosis as well as cardiac dysfunction. These data suggest a new therapeutic paradigm for end stage of heart failure by inhibiting the PDE3A/ICER feedback loop via activating ERK5.
DOI
10.1161/01.RES.0000259045.49371.9c
Montclair State University Digital Commons Citation
Yan, Chen; Ding, Bo; Shishido, Tetsuro; Woo, Chang Hoon; Itoh, Seigo; Jeon, Kye Im; Liu, Weimin; Xu, Haodong; McClain, Carolyn; Molina, Carlos; Blaxall, Burns C.; and Abe, Jun Ichi, "Activation of Extracellular Signal-Regulated Kinase 5 Reduces Cardiac Apoptosis and Dysfunction via Inhibition of a Phosphodiesterase 3A/Inducible cAMP Early Repressor Feedback Loop" (2007). Department of Biology Faculty Scholarship and Creative Works. 266.
https://digitalcommons.montclair.edu/biology-facpubs/266
Rights
NIH Public Access Author Manuscript; available in PMC 2014 July 30. Published in final edited form as: Circ Res. 2007 March 2; 100(4): 510–519. doi:10.1161/01.RES.0000259045.49371.9c.