Figure 1.

Effects of curcumin, GG6 or GG9 on cytokine release from LPS‐stimulated cortical microglia and cell viability. Microglia were cultured for 24 h in medium containing 10% serum, which was replaced with serum‐free medium before pretreatment with curcumin, GG6 or GG9 (1–10 μM) for 1 h followed by stimulation with 100 ng·mL⁻¹ LPS for 6 h. Supernatants were collected and analysed for (A) IL‐1β and (B) TNF‐α release. (C) At the end of incubation, cell viability was also determined by MTT assay. Results are expressed as percentage of cytokine release and cell viability relative to LPS‐stimulated microglia. Data are means ± SEM (n = 5). *P < 0.05, significantly different from LPS alone (dashed line), Kruskal–Wallis followed by Dunn's post hoc test and P‐adjustment according to Bonferroni's method.