Effects of DE on the protein expression of COX-2 and iNOS in LPS-stimulated RAW 264.7 cells. RAW 264.7 cells were pretreated with or without DE (0, 0.5 and 1 mg/mL) and then treated with LPS (1 μg/mL). After 24 h incubation, cell lysates (30 μg/mL) were separated by SDS-PAGE, transferred to a nitrocellulose membrane, and blotted with anti-COX-2, anti-iNOS, and β-actin antibodies. Quantification of COX-2 and iNOS protein expression was performed by densitometric analysis. β-Actin was used as an internal control. The values are expressed as a percentage of the maximal band intensity in the culture treated with LPS alone. Data are the mean ± SD of COX-2 / β-actin (A) and iNOS / β-actin (B) of at least three separate experiments. Bars within the same panel with different letters are significantly different (P <0.05).