Anti-inflammatory effect of litsenolide B2 isolated from Litsea japonica fruit via suppressing NF-κB and MAPK pathways in LPS-induced RAW264.7 cells

• We study the anti-inflammatory effect of LNB2 isolated from Litsea japonica fruit.
• LNB2 inhibited production of inflammatory mediators in LPS-induced RAW 264.7 cells.
• LNB2 inhibited the LPS-induced phosphorylation of NF-κB and MAPKs.

The anti-inflammatory effects of compounds isolated from the Litsea japonica fruit were investigated in LPS-stimulated murine macrophage (RAW 264.7) cells. The results indicated that litsenolide (LN)B2 significantly inhibited the LPS-induced release of pro-inflammatory mediators, such as NO and PGE2. LNC2, and, on the other hand, exhibited cytotoxicity at the same concentrations at which it exhibited an inhibitory property. Therefore, only LNB2 was used for further experimentation. LNB2 reduced the LPS-induced production of pro-inflammatory cytokines. We further investigated the mechanism by which LNB2 inhibits pro-inflammatory mediators and cytokines by examining the level of NF-κB and MAPKs phosphorylation, which all serve as key components in inflammation-induced signaling pathways in RAW 264.7 cells. LNB2 inhibited the LPS-induced phosphorylation of NF-κB and MAPKs. These results suggest that LNB2 has an anti-inflammatory effect, inhibiting the production of pro-inflammatory mediators and cytokines via inhibition of NF-κB and MAPK signaling in LPS-stimulated RAW 264.7 cells.