Figure 5.

EP does not affect IKB degradation but decreases ERK phosphorylation in LPS-stimulated DCs. DCs were pre-treated with 10mM EP for 1 h before 100 ng/ml LPS. (A,B) Cells were harvested 1 h after LPS stimulation and IKBa (A) and IKBb (B) protein expression was detected by western blotting. Densitometry was analyzed by calculating the ratio of IKBa or IKBb to actin. Results are normalized to the untreated control and shown as mean ± SEM of 5–6 independent experiments (n = 5–6). (C) p-ERK/Total ERK detection. Cells were harvested 15 and 30min after LPS stimulation and ERK1/2 protein expression was detected by western blotting. Densitometry was analyzed by calculating the ratio of phosphorylated p-ERK to total ERK. GAPDH was included as a confirmation control only. Results are normalized to the untreated control and shown as mean ± SEM of 7 independent experiments (n = 7). Data was analyzed using the ratio paired two-tailed Student's t-test. *P < 0.05, **P < 0.01, ***P < 0.001, and ****P < 0.0001.