Fig. 7

a–cThe increase of LPS-induced pro-inflammatory markers in si-sEH astrocytes was suppressed by inhibition of STAT3 phosphorylation. The inhibition of STAT3 phosphorylation in LPS-activated astrocytes by the pretreatment of a STAT3 inhibitor, stattic, (10 μM) attenuated the enhanced mRNA expression levels of IL-6 and TNFα resulting from si-sEH, as measured by qPCR (n = 4, p < 0.001 for both IL-6 and TNFα). Stattic significantly suppressed LPS-induced TNFα expression in the scrambled control (p < 0.001) while slightly increasing LPS-induced IL-6 expression. Of note, stattic increased the mRNA expression levels for IL-6 (p < 0.001) and TNFα (p < 0.001) in astrocytes in basal conditions. ***p < 0.001, compared to si-sEH control; ^##p < 0.01, ^###p < 0.001, compared to si-sEH with LPS; ^&&&p < 0.001, compared to si-sEH with LPS. According to the data from Western blot analysis, STAT3 phosphorylation was upregulated in LPS-activated astrocytes (n = 8, p < 0.001) and was further enhanced by pretreatments with AFC, an sEH phosphatase activity inhibitor, (138 ± 6 and 141 ± 4% of LPS-activated astrocytes for doses at 1 and 10 μM, respectively, p < 0.001), but not by pretreatments with AUDA, an sEH hydrolase activity inhibitor, (118 ± 7 and 120 ± 8% of LPS-activated astrocytes for doses at 1 and 10 μM, respectively) (b). All lanes in the representative blot images of the same target protein were obtained from the same blot membrane. ***p < 0.001, compared to control; ^###p < 0.001, compared to control with LPS. In Fig. 7c, LPS-induced STAT3 phosphorylation was reduced in astrocytes overexpressing sEH (59 ± 5% of the control with LPS, n = 10, p < 0.05) as compared to that in plasmid control with LPS (100 ± 5). *p < 0.05, ***p < 0.001. Data are presented as the mean ± SEM. One-way ANOVA and Bonferroni multiple comparison test were performed