In vitro anti-inflammatory effect of ethyl acetate extract from Daphnes Giraldii Cortex and their mechanisms / 中草药

ABSTRACT

Objective: To investigate in vitro anti-inflammatory effect of ethyl acetate extract from Daphnes Giraldii Cortex (EAEDGC) on RAW 264.7 macrophages stimulated with IFN-γ plus LPS and their mechanisms. Methods: IFN-γ plus LPS-stimulated RAW 264.7 macrophage has been used as experimental inflammatory model. Griess reaction for nitric oxide (NO) production, FRAP assay for total anti-oxidant capacity, MTT assay for cell proliferation (availability), RT-PCR for mRNA expression and Western blotting for protein expression examination were performed. Results: EAEDGC could concentration-dependently inhibit NO production in stimulated macrophage. The gene and protein expression of inducible nitric oxide synthase (iNOS) were also suppressed by the herb extract. The treatment by EAEDGC significantly attenuated mRNA of inflammatory cytokines, such as IL-1β, IL-6, and TNF-α, while increased HO-1 expression. The herb element elevated anti-oxidant capacity of the cells. Furthermore, phosphorylation of ERK (p-ERK) was markedly inhibited by EAEDGC. Conclusion: EAEDGC exerts potential anti-inflammatory effects including the suppression of pro-inflammatory mediators, such as IL-1β, IL-6, TNF-α, and increasing HO-1 expression and total antioxidant capacity. EAEDGC could inhibit the NO production and iNOS expression, which may partially contribute to the regulation of ERK/MAPK pathway.