Timosaponin B-II Inhibits Pro-inflammatory Cytokine Induction by Lipopolysaccharide in BV2 Cells

It was reported that the total polysaccharides extracts from Anemarrhenae asphodeloides Bge (Liliaceae, rhizome) could inhibit inflammatory responses in various models. In the present study, the effects of Timosaponin B-II, a purified extract from A. asphodeloidesb, on the expressions of IL-1 beta, TNF-alpha and IL-6, the activity of NF-kappa B and the activation of signal pathway related to NF-kappa B were explored in vitro. Timosaponin B-II significantly attenuated increase of these cytokines on both mRNA and protein levels from LPS-stimulated BV2 cells in a dose-dependent manner. The reporter gene assay also showed that the activation of NF-kappa B induced by LPS was inhibited by pre-treatment with Timosaponin B-II. Moreover, western blot results showed that the activation of p38, JNK and P65 had been decreased. These results suggest that both NF-kappa B signal pathway and MAPK pathway were involved in the inhibitory effects of Timosaponin B-II on the expression of pro-inflammatory cytokines.