Figure 2.

LPS modulated cPLA₂ gene expression via activation of JAK2. Serum-starved 3T3-L1 cells were pretreated with 100 nM or different concentrations of AG490 for 1 h. Or cells were transfected with 100 nM of scramble (Scr) or JAK2 siRNA for 24 h. Inhibitor or siRNA-treated cells were then incubated 20 μg/mL of LPS for the indicated time points (A, B), 16 h (C, D) or 6 h (E). At the end of incubation, cells were harvested and cell lysates or mRNA were extracted. (A, B, C, D) Western blot was used to evaluate the expression of phosphorylated JAK2, total JAK2, cPLA₂ or GAPDH protein. (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 or indicated group. #P < 0.05, as compared with the same time points or LPS treated alone.