芫花素

Cell viability analysis shows that Genkwanin does not affect the cell viability up to a concentration of 50 μM. Genkwanin inhibits the LPS-induced production of NO in a concentration-dependent manner. iNOS only expresses in the present of external stimulus. Genkwanin could not significantly affect the activity of iNOS. The effect of Genkwanin on the production of proinflammatory cytokines is examined. Genkwanin suppresses the productions of TNF-a, IL-1b and IL-6 in LPS stimulated RAW264.7 macrophages in a concentration-dependent manner. Genkwanin significantly suppresses the AP-1 signaling pathway but has little effect on the NF-kB signaling pathway. It is indicated that Genkwanin suppresses the phosphorylation of p38 and JNK in a concentration-dependent manner, but little affects ERK1/2 phosphorylation. Originally identified as an immediate early gene, MKP-1 is then found to be a dual specificity phosphatase acting as a negative regulator of ERK1/2, JNK and p38 MAPK activities, with predominant effects on the latter two. Pretreatment with Genkwanin markedly up-regulates the expression of MKP-1 without affecting MKP-1 mRNA.