Glut4 expression upon Sp1 inhibition and/or LXR induction. A, Effect of the Sp1 inhibitor mithA on Glut4 expression. MEFs were differentiated for 8 d and subsequently treated with mithA for 24 h. Glut4 expression was assessed by real-time PCR and normalized to 18S rRNA. Expression without mithA treatment was set to 100% for each cell type. Data are represented as mean ± sd. *, P < 0.05; **, P < 0.01. B, Glut4 induction by tularic in MEFs-derived adipocytes in the absence and presence of mithA. MEFs were differentiated for 8 d, subsequently treated with mithA or vehicle for 24 h, and then stimulated with 1 μm tularic or dimethylsulfoxide as control for 6 h. Glut4 induction was analyzed by real-time PCR. The results were normalized to 18S rRNA and to expression after control treatment. Data are represented as mean ± sd. *, P < 0.05; **, P < 0.01.