Activation of ERK by sodium tungstate induces protein synthesis and prevents protein degradation in rat L6 myotubes

Abstract

The balance between the rates of protein synthesis and degradation in muscle is regulated by PI3K/Akt signaling. Here we addressed the effect of ERK activation by sodium tungstate on protein turnover in rat L6 myotubes. Phosphorylation of ERK by this compound increased protein synthesis by activating MTOR and prevented dexamethasone-induced protein degradation by blocking FoxO3a activity, but it did not alter Akt phosphorylation. Thus, activation of ERK by tungstate improves protein turnover in dexamethasone-treated cells. On the basis of our results, we propose that tungstate be considered an alternative to IGF-I and its analogs in the prevention of skeletal muscle atrophy.

Keywords: Extracellular signal-regulated kinases 1 and 2; Forkhead box O Family of Transcription Factors; LC3; Mechanistic target of rapamycin; Skeletal muscle; Sodium tungstate.