Figure 4.

Participation of STAT5 in LPS-mediated cPLA₂ gene expression. Serum-starved 3T3-L1 cells were pretreated with AG490 (100 nM) or STAT5-I (10 μM or different concentration) for 1 h. Or cells were transfected with 100 nM of scramble (Scr) or JAK2 siRNA for 24 h. After inhibitor or siRNA treatment, cells were incubated with 20 μg/mL of LPS for the indicated time points (A, B, C), 16 h (D) or 6 h (E). Protein lysates or mRNA were extracted. (A, C, D) Western blot was used to evaluate the phosphorylation of STAT5, total STAT5 or cPLA₂ protein. (B) The phosphorylated STAT5 was quantified and showed as bar graph. (E) RT-PCR was used to analyze the expression of cPLA₂ mRNA. Data are expressed as means ± SEM of at least 3 independent experiments (n≥3). &P < 0.05, as compared with the 0 point group or the indicated group. #P < 0.05, as compared with the same time points or LPS treated alone.