Fig. 4.

Role of p38MAPK and JNK signaling in the regulation of NADPH oxidase activity and ROS production stimulated by LPS in RAW 264.7 macrophages. (A, B) Cells were pretreated with SB203580, a pharmacological inhibitor of p38MAPK, followed by the incubation with LPS for 24 h. NADPH oxidase activity (A) and ROS production (B) were assessed as described previously. Values are presented as the fold change in respective parameters compared to the levels determined in cells stimulated with LPS and are expressed as the mean ± SEM (n=3). (C, D) Cells were treated with LPS for 30 min in the absence or presence of different concentration of SP600125, a selective inhibitor of JNK. NADPH oxidase activity (C) and ROS production (D) were determined as described previously. Data are presented as fold change compared to the LPS-treated cells and are expressed as mean ± SEM (n=3). ^*p<0.05 compared with control cells; ^#p<0.05 compared with cells treated with LPS only.