Role of heterotrimeric G protein and calcium in cardiomyocyte hypertrophy induced by IGF-1
Author
dc.contributor.author
Carrasco Mujica, Loreto
Author
dc.contributor.author
Cea, Paola
Author
dc.contributor.author
Rocco, Paola
Author
dc.contributor.author
Peña Oyarzún, Daniel
Author
dc.contributor.author
Rivera Mejías, Pablo
Author
dc.contributor.author
Sotomayor Flores, Cristian Alejandro
Author
dc.contributor.author
Quiroga, Clara
Author
dc.contributor.author
Criollo Céspedes, Alfredo
Author
dc.contributor.author
Ibarra, Cristián
Author
dc.contributor.author
Chiong Lay, Mario
Author
dc.contributor.author
Lavandero González, Sergio
Admission date
dc.date.accessioned
2019-01-29T13:56:14Z
Available date
dc.date.available
2019-01-29T13:56:14Z
Publication date
dc.date.issued
2014
Cita de ítem
dc.identifier.citation
Journal of Cellular Biochemistry 115:712–720 (2014)
Identifier
dc.identifier.issn
10974644
Identifier
dc.identifier.issn
07302312
Identifier
dc.identifier.other
10.1002/jcb.24712
Identifier
dc.identifier.uri
https://repositorio.uchile.cl/handle/2250/160101
Abstract
dc.description.abstract
In the heart, insulin‐like growth factor‐1 (IGF‐1) is a peptide with pro‐hypertrophic and anti‐apoptotic actions. The pro‐hypertrophic properties
of IGF‐1 have been attributed to the extracellular regulated kinase (ERK) pathway. Recently, we reported that IGF‐1 also increases intracellular
Ca2þ levels through a pertussis toxin (PTX)‐sensitive G protein. Here we investigate whether this Ca2þ signal is involved in IGF‐1‐induced
cardiomyocyte hypertrophy. Our results show that the IGF‐1‐induced increase in Ca2þ level is abolished by the IGF‐1 receptor tyrosine kinase
inhibitor AG538, PTX and the peptide inhibitor of Gbg signaling, bARKct. Increases in the activities of Ca2þ‐dependent enzymes calcineurin,
calmodulin kinase II (CaMKII), and protein kinase Ca (PKCa) were observed at 5 min after IGF‐1 exposure. AG538, PTX, bARKct, and the
dominant negative PKCa prevented the IGF‐1‐dependent phosphorylation of ERK1/2. Participation of calcineurin and CaMKII in ERK
phosphorylation was discounted. IGF‐1‐induced cardiomyocyte hypertrophy, determined by cell size and b‐myosin heavy chain (b‐MHC), was
prevented by AG538, PTX, bARKct, dominant negative PKCa, and the MEK1/2 inhibitor PD98059. Inhibition of calcineurin with CAIN did not
abolish IGF‐1‐induced cardiac hypertrophy. We conclude that IGF‐1 induces hypertrophy in cultured cardiomyocytes by activation of the
receptor tyrosine kinase activity/bg‐subunits of a PTX‐sensitive G protein/Ca2þ/PKCa/ERK pathway without the participation of calcineurin.