Water soluble dexamethasone dex

Water-soluble dexamethasone (Dex) from Sigma Aldrich (St. Louis, MO) was dissolved in water and added to C2C12 myotubes at a final concentration of 100 nM. Dex treatments were initiated starting on Day 5 for 24 h incubations and on Day 6 for shorter (≤12 h) incubations; all cells, control and treatment, were harvested on Day 6. All control cells were incubated with an equal volume of vehicle only. Milrinone was purchased from Selleckchem (Houston, TX, USA); Rolipram and 3-isobutyl-1-methylxanthine (IBMX) were from Cayman Chemical (Ann Arbor, MI, USA); LY294002 and H89 were from Sigma Aldrich (St. Louis, MO, USA); PKI 14–22 amide was from Tocris (Minneapolis, MN, USA). All compounds except Dex were dissolved in DMSO and added to cells at final concentrations of 10 μM for Milrinone, 25 μM for Rolipram, 250 μM for IBMX, 25 μM for LY294002, 10 μM for H89, and 10 μM for PKI 14–22 amide; the treatment times are indicated in the figure legends. When inhibitors were co-incubated with dexamethasone, they were added 15 min prior to Dex treatment.