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

Figure 4

Torilin restores I-κBα phosphorylation and degradation; thereby it inhibits p65-NF-κB nuclear translocation. (a) RAW 264.7 cells were pretreated with the indicated concentrations of torilin for 30 min and incubated with LPS (100 ng/ml) for (15–60 min) time course and then assayed for the phosphorylation and degradation of I-κBα and nuclear translocation of p65 by western immunoblot analysis as described under Materials and Methods. (b and c) RAW macrophages were treated with LPS (100 ngmL⁻¹) and 25 µM torilin, respectively, for the indicated time course before cytoplasmic and nuclear protein fractions were subjected to western blot analyses for p65 (upper panel) and p50 (middle panel) of cytoplasmic (b) and nuclear (c) proteins, respectively. β-Actin and ploy(ADP-ribose) polymerase (PARP) were used as a control for the cytoplasmic and nuclear protein loading, respectively. Images are representative of 3 or 4 independent experiments. Values in bar graphs are means ± SE of at least 4 independent experiments performed in triplicate. Significance was determined using Student’s t-test. , , . he significance of IkB degradation upon LPS activation associated with p-IkB phosphorylation in comparison with torilin treated group as analysed from western blot band size.

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