Figure 6.

Luteolin blocks LPS-induced IκBα phosphorylation/degradation and IκB kinase activity directly. (a) BMDCs isolated from cis-NF-κB^EGFP mice were pretreated with luteolin (50 µm) for 1 hr, and then stimulated with LPS (1 µg/ml) for various times (0–60 min). Total protein was extracted, and 20 µg of protein was subjected to SDS—PAGE followed by IRAK-1, phospho-IκBα, IκBα, phospho-RelA, phospho-p38, p38, and β-actin immunoblotting using the ECL technique. Results are representative of three independent experiments. (b) BMDCs isolated from cis-NF-κB^EGFP mice were stimulated with LPS (1 µg/ml) for 30 min. Whole cell extracts were immunoprecipitated with an anti-IKKγ/protein-A beads, and kinase reactions performed as described in the legend to Fig. 4. These results are representative of two independent experiments. Veh, DMSO vehicle; Lut, Luteolin.