Figure 2. AMPK activation is inversely correlated with PXR activation.

(a) HepG2 cells were deprived of serum and glucose for 24 h. The cells were then treated with or without 50 mM glucose. Whole-cell lysates were probed with antibodies as indicated (left panel). AMPK activity (pAMPK Thr 172) was normalized to total AMPK expression. Other protein expression quantifications were normalized to actin. HepG2 PXR CYP-luc cells were deprived as described in the legend for Fig. 1, and luciferase activities were measured 24 h after the cells were treated with glucose and metformin (an AMPK activator) (b) or compound C (an AMPK inhibitor) (c). The P-values were determined using ANOVA with Tukey’s HSD test: *P < 0.05, **P < 0.01, ***P < 0.001, ****P < 0.0001, n = 3. Results are expressed as the mean ± SE.