Anti-inflammatory effects of methanol extracts of the root of Lilium lancifolium on LPS-stimulated Raw264.7 cells

Abstract

Aim of the study: Lilium lancifolium is commonly used to treat bronchitis, pneumonia, etc. In this study, we investigated the anti-inflammatory effects of methanol extracts of the root of Lilium lancifolium (LL extracts) in LPS-stimulated Raw264.7 cells.

Material and methods: Levels of NO, PGE(2) and pro-inflammatory cytokines (IL-6 and TNF-alpha) in the supernatant fraction were determined using sandwich ELISA. Expression of COX-2 and iNOS, phosphorylation of MAPK subgroups (ERK and JNK), and NF-kappaB activation in extracts were detected via Western blot and immunocytochemistry assays.

Results: The LL extract significantly inhibited NO, PGE(2), IL-6 and TNF-alpha production in LPS-stimulated cells, and suppressed iNOS and COX-2 expression. A mechanism-based study showed that phosphorylation of ERK1/2 and JNK and translocation of the NF-kappaB p65 subunit into nuclei were inhibited by the LL extract. Furthermore, interleukin-4 and interleukin-13 production in Con A-induced splenocytes was suppressed.

Conclusion: These results indicate that anti-inflammatory effects of methanol extracts from Lilium lancifolium are due to downregulation of iNOS and COX-2 via suppression of NF-kappaB activation and nuclear translocation as well as blocking of ERK and JNK signaling in LPS-stimulated Raw264.7 cells.