Effect of Nrf2-knockdown on DHA, EPA, or 4-HHE-suppression of sEH protein expression. RAECs were transfected with Nrf2 Small interfering RNA (siRNA) or control siRNA. After 24 h, the cells were incubated with DHA (100 µM), EPA (100 µM), or 4-HHE (15 µM) for another 48 h. Whole cell lysates were subjected to western blot analysis. (A) Nrf2 and β-actin expression was determined by western blotting. (B–D) sEH and β-actin expression levels were determined by western blotting. Each value represents the mean ± SEM. n = 6-10. * p < 0.05, ** p < 0.01, *** p < 0.001, compared with control. NS, no significant difference.