Torilin Inhibits Inflammation by Limiting TAK1-Mediated MAP Kinase and NF-κB Activation

Figure 5

Torilin arrests AP-1 and NF-κB DNA binding and reporter gene expression in LPS-stimulated RAW 264.7 cells. RAW macrophages were treated with vehicle or torilin (as indicated) and stimulated with LPS for 45 min before nuclear protein was isolated. DNA binding was analyzed using specific γ32P-labeled oligonucleotide probes for NF-κB (a) or AP-1 (b). Specificity was demonstrated by coincubation with a 25-fold excess of unlabeled specific probe of NF-κB and AP-1 for competition. Cells were transiently transfected with NF-κB (c) or AP-1 (d), plasmids treated with the indicated concentrations of torilin and LPS (100 ngmL⁻¹) for 6 h and assayed for CAT expression using a CAT enzyme-linked immunosorbent assay kit. Each column shows the mean ± SEM of quadruplicate determinations. Luciferase activity was normalized to β-galactosidase activity. Images are representative of 3 independent experiments. , , as compared with vehicle.

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