Fig. 3.

Effect of TNF-α on astrocyte activation in vitro. a, b In vitro experimental design and c, scheme representing astrocyte phenotypic switch from resting A0 to classical inflammatory A1. d, e Astrocytes were stimulated with TNF-α for 1, 3, 6, or 24 h and IL-6 (d) and MCP-1 (e) mRNA levels were analyzed by RT-PCR. Bar graphs represent means ± SD of five independent experiments normalized to RPL. **p < 0.001 when compared to control non-stimulated cells. f Astrocytes were stimulated with TNF-α (0, 15, 30 and 60 min) and IκB-α protein expression was evaluated by western blotting and normalized to β-tubulin. Bar graphs represent means ± SD of five independent experiments. *p < 0.05 vs. control non-stimulated cells