Figure 5

Inhibition of JNK or ERK signaling on lipopolysaccharide (LPS)-mediated microglia activation. (A) Inhibitory effect of SP600125 and U0126 on JNK1/2 and ERK1/2 activation. BV2 cells were treated with SP600125 (20 μM) or U0126 (10 μM) for 30 minutes prior to LPS treatment (100 ng/mL) for one hour. (B) Measurement of NO production in culture media (upper panel) and Western blot analysis of inducible nitric oxide synthase (iNOS) expression (lower panel). Cells were pretreated with SP600125 (20 μM) or U0126 (10 μM) for 30 minutes followed by stimulation of LPS (100 ng/mL) for 24 hours. (C) The mRNA expression of TNF-α and IL-1β. Cells were pretreated with SP600125 (20 μM) or U0126 (10 μM) for 30 minutes followed by stimulation of LPS (100 ng/mL) for six hours. The mRNA levels of each cytokine were quantified and normalized with their respective β-actin. Each value was then expressed relative to the one treated with LPS alone, which was set as 100. *P < 0.05. Values are means ± SE of three independent experiments. SP, SP600125. LPS, lipopolysaccharide.