Figure 5: Cox-2 mediates palmitate-induced suppression of Akt phosphorylation.

(A) 95% confluent C2C12 cells were treated with ethanol vehicle, 500 μM PA, 200 μM OA, or 500 μM PA plus 200 μM OA in DMEM with 2% BSA for 12 h. Cox-2 and p-Akt were examined using Western blot. GAPDH was used as an internal protein loading control. (B,C) 95% confluent C2C12 cells were incubated in the presence of different concentration of PA (0,100 μM, 200 μM, 300 μM, 400 μM, 500 μM) in DMEM with 2% BSA for 12 h or in the presence of 500 μM PA in DMEM with 2% BSA for the indicated time. (D,E) Inhibition of Cox-2 reduced PA-induced insulin resistance. 95% confluent C2C12cells were treated with ethanol vehicle (CON) or 500 μM PA in DMEM with 2% BSA for 12 h. The concentrations of inhibitors used are indicated; otherwise the highest concentration was used.