AC pretreatment inhibits IκB protein degradation and IKK activity. NOD BMDCs were pretreated with ACs and stimulated with LPS as in Figure 1. (A) Cytoplasmic IκBα, IκBβ, IκBϵ, and β-actin protein were detected by Western blot using the same blot. Densitometric readings represent the ratio of intensity of IκB protein to β-actin expression per unit area and are represented as an arbitrary unit. (B) In vitro IKK activity was determined by measuring phosphorylation of an IκBα-GST substrate. Densitometric analysis represents the intensity of phosphorylated (P) IκBα-GST in arbitrary units. The amount of IKK1 and IKK2 immunoprecipitated in the samples was analyzed by Western blot. Western blot was used to detect (C) phospho-JNK versus JNK, (D) phospho-ERK versus ERK, and (E) phospho-p38MAPK versus p38MAPK in whole cell lysates. Data are representative of 3 independent experiments.