Figure 3.

Tart cherry inhibits the activation of the extracellular signal-regulated kinase (ERK) and p38 mitogen-activated protein kinase (MAPK) pathways triggered by PM₁₀. (A) Time-dependent response of PM₁₀ (100 μg/mL) on the activation of mitogen-activated protein kinase (MAPK) in HaCaT cells determined by Western blot. (B) The effect of tart cherry (TC, 200 μg/mL) on the phosphorylation of ERK and p38 MAPK is shown. (C) Cells pre-treated with NAC prior to exposure to PM₁₀ for 30 min. (D) Cells pretreated with SB203580 (10 μM) and PD98059 (10 μM) as inhibitors for p38 MAPK and ERK were incubated with PM₁₀ for 24 h. Cell viability was determined. (A–D) Data are represented as the means ± S.E. n = 3. * p ≤ 0.01 vs. control. # p ≤ 0.05 vs. PM₁₀ alone. ROD, relative optical density.