siRNA targeting of GSK-3β inhibits TNF-α production by LPS-stimulated BV-2 cells. (A) Cells were transfected with GSK-3β-specific (50 and 100 nM) or control siRNA (100 nM) duplexes for 48 h. Endogenous GSK-3β protein was analyzed by western blotting. (B) Parallel cultures were exposed to 100 ng/ml LPS for 6 h. Released TNF-α was measured by ELISA. Data are presented as mean ± SEM for three independent experiments. *p < 0.05; **p < 0.01 compared with control siRNA-transfected cultures. The level of TNF-α in control cultures was 6.08 ± 0.41 ng/ml.