The activation of SREBP-1c was blocked using the inhibitor fatostatin (10 μmol/L) (Sigma, USA). After 24 h, cells were lysed and the protein concentration was determined using the method of Lin et al (2007). Equal amounts of protein were analyzed by Western blotting using antibodies specific for SREBP-1c (USA) and β-actin (USA).
ChREBP-siRNA cells and SREBP-1c blocked cells were cultured in glucose-free and/or serum-free DMEM medium and subsequently cultured in the absence or presence of glucose (20 mmol/L) with 0 or 200 nmol/L insulin, as indicated in the figure legends. Sodium pyruvate (2 mmol/L) (Sigma-Aldrich) was added to the medium to replace glucose as carbon source when cells were cultured in glucose-free medium. T0901317 (1 μmol/L) (Sigma) was used as agonist to promote the activation of LXRα. These concentrations were chosen base on initial dose-response experiments (data not shown).