Fig. 1

GLP attenuates LPS- and Aβ-induced inflammatory response in microglia. BV2 (a–e, k) and primary mouse microglia (f–j, l) were pre-treated with GLP for 2 h followed by LPS or Aβ stimulation for further 24 h. GLP inhibited the LPS- and Aβ-induced pro-inflammatory cytokine levels (IL-1β, IL-6 and iNOS) and promoted anti-inflammatory cytokine (TGFβ) mRNA expressions. The effect of GLP on IL-6 protein expression in BV2 (k) and primary microglia (l) was determined by ELISA. The IC₅₀ values for GLP were calculated from concentration-response curves in BV2 and primary microglia (m). Values were expressed as mean ± SEM for at least three independent experiments, each performed in duplicates. One-way ANOVA with Tukey’s multiple comparison test revealed difference from untreated control (*) and LPS- or Aβ-stimulated condition (#) (compared with control: *p < 0.05, **p < 0.01, ***p < 0.005, and ****p < 0.0001; compared with LPS- or Aβ-stimulated condition: ^# p < 0.05, ^## p < 0.01, ^### p < 0.005, and ^#### p < 0.0001)