Fig. 3.

Quercetin inhibits the LPS-induced activation of the NF-κB signaling pathway in lamellar keratinocytes. A The protein expression of phosphorylated p65 was detected by Western blot. Lamellar keratinocytes (passages 2–4) were pretreated with 0, 5, 10, and 20 µM pyrrolidinedithiocarbamate (PDTC, an NF-κB inhibitor) for 1 h. B The protein expression of phosphorylated p65 was calculated by densitometric analysis. C The protein expression of p-p65, p65, p-IκBα, and IκBα was detected by Western blot. Keratinocytes were pretreated with or without PDTC (10 µM) for 1 h and subsequently treated with LPS (10 µg/mL) and quercetin (25 µM) for 24 h. D-G The protein expression of (D) p-p65, (E) p65, (F) p-IκBα, and (G) IκBα was calculated by densitometric analysis. The data are presented as mean ± standard deviation from three independent biological replicates (n = 3). The symbol “+” in the diagram indicates the addition of a substance, while “-” denotes no addition. The symbol * indicates P < 0.05, and ** indicates P < 0.01