Activation of the Nrf2-ARE signaling pathway induced by LG2055 treatment is slightly suppressed by inhibition of ERK.

<p>(A, B) MEF cells were preincubated with 20 μM U0126 for 1 h and treated with LG2055 for 24 h. (A) The total cell lysates were analyzed by western blotting to compare the Nrf2 protein levels. The relative expression level of Nrf2 normalized by β-actin protein expression was quantitated. (B) The mRNA expression level of HO-1 was determined by quantitative real time-PCR analysis. (C) MEF cells were preincubated with 20 μM SP600125 (SP) or 20 μM U0126 for 1 h and treated with LG2055 for 24 h. The cells were fractionated into cytosolic and nuclear fractions using the Focus SubCell kit. Each fraction was analyzed by western blotting to compare Nrf2 protein levels. (A, B) Each experiment was performed in triplicate; the data are shown as the means ± SD. Values not sharing a common letter are significantly different according to one-way ANOVA and Tukey-Kramer post-test analysis with the value of <i>p</i> <0.05.