Figure 4.

Activation of p38, AMPK and PKCδ by 5-CQA. (A) Western blot analysis for Nrf2 phosphorylation by 5-CQA. Cells were treated with 100 μM 5-CQA for 1 to 12 h. Total and phosphorylated Nrf2 was determined by western blotting. (B) Effects of 5-CQA on phosphorylation of Nrf2 upstream kinases. Western blot analyses for ERK1/2, p38, AMPK and PKCδ phosphorylation were performed on cell lysates incubated with 100 μM 5-CQA for 1 to 12 h. (C, D) Inhibition of 5-CQA induced GCL and HO-1 expression by chemical inhibitors. Cells were concomitantly treated with 100 μM 5-CQA and 10 μM PD98059 (PD), 10 μM SB203580 (SB), 10 μM SP600125 (SP), 5 μM Compound C (Comp C) or 2.5 μM Rottlerin (Rott) for 12 h. Results were confirmed in three replicate experiments.