Study on Effects of Tripterygium Wilfordii Polycoride in Resisting Macrophage Inflammation and Regulating Inflammation Via TLR4/NF-κB

To investigate the effect of Tripterygium wilfordii polycoride (TWP) on LPS-induced macrophage inflammatory response, particularly the inhibitory effect on inflammatory factors TNF-α and IL-1β and the regulatory effect on inflammation via TLR4/NF-κB. The MTT method was adopted to test the effects of tested drugs, TWP, dexamethasone (DXM) and azathioprine (AZA) on cell growth to define the appropriate concentration. LPS was used to induce the inflammatory reaction in mouse RAW264. 7 cell lines. The Elisa kit was adopted to test the release level of TNF-α and IL-1β. The Western blotting was applied to test the protein expressions of TNF-α and IL-1β. The RT-PCR was adopted to test the expressions of TLR4 and NF-κB. According to the results, TWP could inhibit the release of macrophage inflammatory factors TNF-α and IL-1β in a dose dependent manner. All of TWP groups showed a weaker efficacy than that of the DXM group. But the TWP high dose group revealed a better effect on TNF-α and equal effect on IL-1β compared with the AZA group. TWP show an equal or better effect in down-regulating TLR4 and NF-κB p65 expressions in a dose dependent manner than DXM and AZA. In conclusion, TWP could inhibit TLR4 and NF-κB p65, which may be related to the down-regulation of TLR4 and NF-κB p65 receptor expressions.