The Antiaging Activity of Ergothioneine in UVA-Irradiated Human Dermal Fibroblasts via the Inhibition of the AP-1 Pathway and the Activation of Nrf2-Mediated Antioxidant Genes

Figure 7

EGT-mediated Nrf2 activation by ERK, JNK, and PKC signaling pathways in HSF cells. (a) Cells were pretreated with pharmacological inhibitors of ERK (PD98059, 30 μM), JNK (SP600125, 25 μM), MAPK p38 (SB203580, 20 μM), PI3K/AKT (LY294002, 30 μM), or PKC (GF109203X, 2.5 μM) for 30 min followed by EGT (0.5 μM) for 1 h. Western blot results showed the nuclear Nrf2 expression with response to inhibitors in the presence of EGT. (b) The protein levels of HO-1, γ-GCLC, and NQO-1 were estimated by immunoblot analysis. Cells were pretreated with inhibitors of ERK (PD98059, 30 μM), JNK (SP600125, 25 μM), or PKC (GF109203X, 2.5 μM) for 30 min followed by EGT (0.5 μM) treatment for 6 h. Protein levels of respective markers are significant compared to EGT alone (0.5 μM) treated cells (without inhibitors). (c) EGT activated ERK, JNK, and PKC signaling pathways. Cells treated with 0.5 μM EGT for 15-120 min and the protein levels of activated forms of ERK, JNK, and PKC were evaluated using a specific antibody to p-ERK, ERK, p-JNK, JNK, and PKC by immunoblot analysis. Data were presented as of three or more experiments. Statistical significance was considered as as compared to untreated control cells and ^# and ^## as compared to the EGT alone treated cells.

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