Figure 3: BKFE inhibits ER stress in PA-treated SV40 MES13 cells. (a) SV40 MES13 cells were pretreated with 20 μg/ml BKFE for 1 h and then treated with 100 μM PA for 18 h. The protein levels of ER stress-related genes were measured by western blotting (three to six independent experiments). (b) The relative expression of the proteins was normalized to that of β-actin and quantified using the ImageJ software. p<0.05, p<0.01, and p<0.001. (c) Cells were pretreated with 20 μg/ml BKFE for 1 h and then treated with 100 μM PA for 9 h. XBP-1 mRNA splicing was analyzed using RT-PCR (three independent experiments).