Mume Fructus Water Extract Inhibits Pro-Inflammatory Mediators in Lipopolysaccharide-Stimulated Macrophages

Mume Fructus (Family Rosaceae) is used as a traditional drug and health food in Asian countries. However, its therapeutic mechanisms and effects on macrophage-mediated inflammation remain unknown. In this study we examined the effect of Mume Fructus water extract (MFWE) on pro-inflammatory mediators in lipopolysaccharide (LPS)-stimulated RAW 264.7 cells. The investigation focused on whether MFWE inhibited nitric oxide (NO) and prostaglandin (PG) E₂ productions, as well as the expressions of inducible NO synthase (iNOS), cyclooxygenase (COX)-2, interleukin (IL)-6, nuclear factor-κB (NF-κB), and mitogen-activated protein kinases (MAPKs) in LPS-stimulated RAW 264.7 cells. We found that MFWE inhibited LPS-induced NO, PGE₂, and IL-6 productions as well as the expressions of iNOS and COX-2. Furthermore, MFWE suppressed the LPS-induced phosphorylations of p38 MAPK and extracellular signal-regulated kinase MAPK, as well as IκBα degradation and NF-κB activation. These results suggest that MFWE has inhibitory effects on LPS-induced PGE₂, NO, and IL-6 production, as well as the expressions of iNOS and COX-2 in the murine macrophage. These inhibitory effects occur through blockades on the phosphorylation of MAPKs following IκBα degradation and NF-κB activation.