[Effect of geniposide on LPS-induced activation of TLR4-NF-κB pathway in RAW264.7 macrophage cell line].

Objective: To study the anti-inflammatory mechanism of geniposide and observe the effect of geniposide on the expression of Toll-like receptor 4 (TLR4), the activity of NF-κB, and the release of pro-inflammatory cytokines- TNF-α, IL-1, and IL-6-in the RAW264.7 macrophages treated with lipopolysaccharide (LPS).

Methods: There were three experimental groups, including the control group, LPS group and LPS combined with geniposide group in this study. RAW264.7 macrophage cells were treated with LPS to induce cellular inflammation. Cell proliferation was measured by CCK-8. The concentrations of TNF-α, IL-1, and IL-6 in cell culture media were measured by ELISA. mRNA levels of TLR4 and P65 were examined by real-time PCR. The protein levels of p-IκB, P65, p-P65 and TLR4 were detected by Western blotting.

Results: Geniposide had no effect on cell proliferation. However, geniposide down-regulated the expression of TNF-α, IL-1, and IL-6, and also inhibited the expression of TLR4 and the activity of NF-κB.

Conclusion: Geniposide exerts its anti-inflammatory effect through inhibiting the activity of NF-κB in the TLR4-NF-κB pathway in macrophages.