First Author | Purcell NH | Year | 2007 |
Journal | Proc Natl Acad Sci U S A | Volume | 104 |
Issue | 35 | Pages | 14074-9 |
PubMed ID | 17709754 | Mgi Jnum | J:124903 |
Mgi Id | MGI:3722752 | Doi | 10.1073/pnas.0610906104 |
Citation | Purcell NH, et al. (2007) Genetic inhibition of cardiac ERK1/2 promotes stress-induced apoptosis and heart failure but has no effect on hypertrophy in vivo. Proc Natl Acad Sci U S A 104(35):14074-9 |
abstractText | MAPK signaling pathways function as critical regulators of cellular differentiation, proliferation, stress responsiveness, and apoptosis. One branch of the MAPK signaling pathway that culminates in ERK1/2 activation is hypothesized to regulate the growth and adaptation of the heart to both physiologic and pathologic stimuli, given its known activation in response to virtually every stress- and agonist-induced hypertrophic stimulus examined to date. Here we investigated the requirement of ERK1/2 signaling in mediating the cardiac hypertrophic growth response in Erk1(-/-) and Erk2(+/-) mice, as well as in transgenic mice with inducible expression of an ERK1/2-inactivating phosphatase in the heart, dual-specificity phosphatase 6. Although inducible expression of dual-specificity phosphatase 6 in the heart eliminated ERK1/2 phosphorylation at baseline and after stimulation without affecting any other MAPK, it did not diminish the hypertrophic response to pressure overload stimulation, neuroendocrine agonist infusion, or exercise. Similarly, Erk1(-/-) and Erk2(+/-) mice showed no reduction in pathologic or physiologic stimulus-induced cardiac growth in vivo. However, blockade or deletion of cardiac ERK1/2 did predispose the heart to decompensation and failure after long-term pressure overload in conjunction with an increase in myocyte TUNEL. Thus, ERK1/2 signaling is not required for mediating physiologic or pathologic cardiac hypertrophy in vivo, although it does play a protective role in response to pathologic stimuli. |