Figure 5.
Effect of DCI on insulin receptor (IR) phosphorylation and the IRS-1/AKT pathway in α-TC1-6 cells exposed to palmitate. Immunoprecipitation and Western blot analysis for total IR (Tyr1150/1151-β subunit) (p-IR-β) and total IR; Western blot analysis for p-IRS-1 (Tyr612), total IRS-1 (IRS-1), p-AKT (Ser 473), total AKT (AKT), and β-actin: αTC1-6 cells were treated with DCI (0.1 or 1 mM for 48 h) in the presence or absence of palmitate (0.5 mM for 48 h) and acutely stimulated with insulin (10−9 M for 5 min). (A) Representative immunoblot of three independent experiments. (B) Means ± SEM of densitometric analysis. One-way ANOVA followed by Bonferroni test (n = 3) was used to evaluate statistical significance in insulin-stimulated cells treated with increasing concentrations of DCI with respect to insulin-stimulated controls in the absence and presence of palmitate: * p < 0.05, ** p < 0.01, *** p < 0.001. n.s., not significant; DCI, D-chiro-inositol.