Insulin-like growth factor-1 suppresses the Myostatin signaling pathway during myogenic differentiation

A. Retamales, R. Zuloaga, C. A. Valenzuela, C. Gallardo-Escarate, A. Molina, J. A. Valdés

Research output: Contribution to journalArticlepeer-review

38 Citations (Scopus)

Abstract

Myogenic differentiation is a complex and well-coordinated process for generating mature skeletal muscle fibers. This event is autocrine/paracrine regulated by growth factors, principally Myostatin (MSTN) and Insulin-like Growth Factor-1 (IGF-1). Myostatin, a member of the transforming growth factor-β superfamily, is a negative regulator of skeletal muscle growth in vertebrates that exerts its inhibitory function by activating Smad transcription factors. In contrast, IGF-1 promotes the differentiation of skeletal myoblasts by activating the PI3K/Akt signaling pathway. This study reports on a novel functional crosstalk between the IGF-1 and MSTN signaling pathways, as mediated through interaction between PI3K/Akt and Smad3. Stimulation of skeletal myoblasts with MSTN resulted in a transient increase in the pSmad3:Smad3 ratio and Smad-dependent transcription. Moreover, MSTN inhibited myod gene expression and myoblast fusion in an Activin receptor-like kinase/Smad3-dependent manner. Preincubation of skeletal myoblasts with IGF-1 blocked MSTN-induced Smad3 activation, promoting myod expression and myoblast differentiation. This inhibitory effect of IGF-1 on the MSTN signaling pathway was dependent on IGF-1 receptor, PI3K, and Akt activities. Finally, immunoprecipitation assay analysis determined that IGF-1 pretreatment increased Akt and Smad3 interaction. These results demonstrate that the IGF-1/PI3K/Akt pathway may inhibit MSTN signaling during myoblast differentiation, providing new insight to existing knowledge on the complex crosstalk between both growth factors.

Original languageEnglish
Pages (from-to)596-602
Number of pages7
JournalBiochemical and Biophysical Research Communications
Volume464
Issue number2
DOIs
Publication statusPublished - 30 Jul 2015

Keywords

  • Crosstalk
  • IGF-1
  • Myoblast differentiation
  • Myostatin

ASJC Scopus subject areas

  • Biophysics
  • Biochemistry
  • Molecular Biology
  • Cell Biology

Fingerprint

Dive into the research topics of 'Insulin-like growth factor-1 suppresses the Myostatin signaling pathway during myogenic differentiation'. Together they form a unique fingerprint.

Cite this