Figure 2.

LXRα is involved in the upregulation of ABCA1 and ABCG1 by ibrolipim. Cells were treated with ibrolipim at different concentrations or different exposure times as indicated. A and B, The expression of LXRα were measured at mRNA levels by real-time PCR. C and D, LXRα protein expressions were measured by Western blot. E, F, G, H and I, THP-1 macrophage-derived foam cells were transfected with control or LXRα siRNA and then incubated with ibrolipim (50 μmol/L) for 24 h. E, Protein samples were immunoblotted with anti-LXRα or anti-β-actin antibodies. Data represent three experiments with different cell preparations. F and G, mRNA and protein expression of ABCA1 and ABCG1 were determined using real-time PCR and Western blot. H and I, Cholesterol efflux to apoA-I or HDL from THP-1 macrophage-derived foam cells were analyzed by liquid scintillation counting assays as shown above. Similar results were obtained in three independent experiments. Data are mean±SD. ^bP<0.05 vs baseline.