Figure 7. XN attenuates NF-κB signaling in IEC-6 cells.

(A) IEC-6 cells were pretreated with the indicated concentrations of XN for 24 h and treated H₂O₂ (0.5 mM) for 6 h. MTT assay was performed for the measurement of cell viability. (B) The effect of XN on the expression of COX-2 was analyzed by Western blot analysis in H₂O₂- or LPS (1 μg/ml)-treated IEC-6 cells. (C) The effect of XN on the expression of pIκBα, IκBα, IKKα, IKKβ, pERK and ERK was analyzed by Western blot analysis in H₂O₂- or LPS (1 μg/ml)-treated IEC-6 cells. (D) IEC-6 cells were transfected with NF-κB-Luc plasmids. At 24 h after transfection, IEC-6 cells were treated with or without LPS (or H₂O₂) for 6 h, in the presence or absence of XN (25 μM) and then performed a reporter assay for the transcriptional activity of NF-κB. Data are representative of three independent experiments. The data represent mean ± SD; ^*P < 0.05 and ^**P < 0.01 vs. vehicle control; ^##P < 0.01 vs. H₂O₂- or LPS-treated cells.