Fig. 4.

Effect of Tan on AP-1 expression, DNA binding activity, and transcriptional activity. A: THP-1-derived macrophages were treated with Tan (1, 3, or 10 μM) or vehicle (0.1% DMSO) for 30 min followed by stimulation with oxLDL (50 μg/ml) for 6 h and the nuclear protein level of c-Fos, c-Jun, or histone H1 were determined by Western blotting. B: Nuclear extracts (2 μg aliquots) were complexed with biotin-labeled AP-1 probe and assayed for AP-1 DNA binding activity by EMSA. Specificity of binding was confirmed by cold competition experiments with a 100-fold molar excess of unlabeled AP-1 duplex oligonucleotide (n = 3). C: Dual luciferase reporter assays were performed to evaluate the influence of Tan treatment on AP-1-dependent transcriptional activity. Data are expressed as the means ± SEM (n = 3). *P < 0.05 versus vehicle-treated group.