Palmitate induced insulin resistance in C2C12 myotubes. Myotubes were treated with indicated concentrations of palmitate for 24 hours. (A) Cell viability of C2C12 myotubes was evaluated by MTT assay. (B) Cells were stimulated with insulin (100 nM) for 15 min before harvest. Phosphorylated Akt1 (Ser473) and phosphorylated p70S6K (Ser371) were immunoprobed in western blot. GAPDH was detected as internal control. (C) 2NBDG uptake was carried out as described in Materials and Methods and intracellular fluorescence intensity was measured by a microplate reader. *p<0.05 vs. control stimulation with insulin. (D) The transcription of Glut4 gene was measured by qRT-PCR. The values were monitored by 18S and expressed as mean±SEM (n=3). *p<0.05 vs. control (CTL). PA, palmitate.