Fig. 4.

PAE attenuates ER stress in MPP⁺-treated SH-SY5Y cells. A After pre-incubation with different concentrations of PAE for 2 h, SH-SY5Y cells were treated with or without MPP⁺ (500 μM) for another 48 h, the protein levels of GRP78, p-IRE1α, IRE1α, p-JNK, JNK, p-eIF2α, eIF2α and CHOP were determined by Western blot. PAE treatment reversed MPP⁺-caused up-regulation of GRP78 (B), p-IRE1α/IRE1α ratio (C), p-JNK/JNK ratio (D), p-eIF2α/eIF2α ratio (E) and CHOP (F). Results are expressed as mean ± SD, n = 3, ^*p < 0.05, ^**p < 0.01, ^***p < 0.001, vs. control group, ^#p < 0.05, ^##p < 0.01, vs. MPP⁺ treated group