Figure 2

Palmitate induced insulin resistance is alleviated by nSMase inhibition. (A) After palmitate treatment, C2C12 myotubes were starved for 30 min. Myotubes were then treated with or without insulin for 10 min followed by lysing in lysis buffer. Insulin induced Akt phosphorylation was measured in total cell lysate by Western blotting. Unphosphorylated levels of Akt were also measured as control for phosphorylation (Upper panel). Lower panel: quantification of Akt phosphorylation (n = 6, ***P < 0.001, **P < 0.01) (B) C2C12 cells were treated with or without palmitate for 2 hrs in presence or absence of nSMase inhibitor (GW4869). Insulin was also present in the treatments for indicated sets. Gene expression level of PDK4 was analyzed by quantitative real time PCR using β-actin as housekeeping gene control. Data are presented as mean + standard deviation. n = 4, **P < 0.01, *P < 0.05, ns: not significant, one way ANOVA with Newman-Keuls post test was performed for statistical analyses.