Fig. 5

Hecubine abrogated the LPS-induced imbalance of TREM2 and TLR4 by down-regulating MAPK and PI3K/AKT signaling pathways in LPS-activated BV2 microglial cells. Cells were pretreated with Hecubine for 1 h and then stimulated with/without LPS. After that, the protein levels of TREM2 (Kruskal-Wallis test of One-way ANOVA) (a), TLR4 (Kruskal-Wallis test of One-way ANOVA) (b), MyD88 (c), the total and phosphorylated p38 MAPK (e), JNK (f), ERK 1/2 (g), and AKT (h) levels, were determined by Western blotting (a-g, n = 3; h, n = 6). (d) Cells were transfected with negative control shRNA or TREM2 shRNA, and then TLR4 expression level in BV2 cells after treatment with Hecubine or LPS was assessed by Western blot analysis. Quantitative analysis was carried out using ImageJ. – and + represent the absence and presence of LPS (800 ng/ml), respectively. The data are presented as the mean ± SD of three independent experiments. *p < 0.05, **p < 0.01, and ***p < 0.001 vs. LPS-treated group; ###p < 0.001 vs. control; ns, not significant; One-way ANOVA with Dunnett’s multiple comparisons test.