Study on effect of total saponins from Semen Nigellae on inflammatory mediators and ERK/MAPK pathway in stimulated macrophage

OBJECTIVE: To study the anti-inflammatory mechanism of total saponins from Semen Nigellae (TSSN). METHOD: IFN-gamma plus LPS stimulated RAW 264. 7 macrophage has been used as inflammatory experimental model. Griess reaction for nitric oxide production, FRAP assay for total antioxidant capacity, RT-PCR for mRNA expression and Western blot for protein expression examination were performed. RESULT: TSSN inhibited NO production in a dose-dependent manner. The gene and protein expression of iNOS were also suppressed by the herb extract. TSSN treatment significantly attenuated mRNA of inflammatory mediators such as COX-2, IL-1beta, IL-6 while increased PPAR-gamma gene and protein expression. Furthermore, phosphorylation of ERK (p-ERK) was markedly inhibited by TSSN. CONCLUSION: TSSN suppressed pro-inflammatory mediators such as COX-2, IL-1beta, IL-6 and increased anti-inflammatory mediator PPAR-gamma expression. Meanwhile, TSSN inhibited over production of NO and iNOS expression through ERK/MAPK pathway.