Anti-inflammatory effects of Danggui Liuhuang Decoction () in RAW 264.7 cells

OBJECTIVE: To elucidate the molecular mechanisms underlying the anti-inflammatory effects of Danggui Liuhuang Decoction () or Dangkwiyughwang-tang (DGLHT) water extract. METHODS: Effect of DGLHT on the lipopolysaccharide (LPS)-induced production of several pro-inflammatory mediators, including nitric oxide (NO), prostaglandin E(2) (PGE(2)), and interleukin-6 (IL-6) were examined by using enzymelinked immunosorbent assay. To determine the underlying mechanism of the inhibitory effects of DGLHT, the expression levels of inducible NO synthase (iNOS) and cyclooxygenase-2 (COX-2) protein, as well as iNOS, COX-2, and IL-6 mRNA levels were examined by Western blot and reverse transcription polymerase chain reaction (RT-PCR). Mitogen-activated protein kinases (MAPKs) in LPS-stimulated RAW 264.7 cells were also examined by Western blot. RESULTS: DGLHT inhibited LPS-induced production of NO, PGE(2), and IL-6 productions and the expressions of iNOS and COX-2. Furthermore, DGLHT suppressed LPS-induced phosphorylation of extracellular signal-regulated kinase 1/2 (ERK1/2). CONCLUSIONS: DGLHT has inhibitory effects on the LPSinduced production of PGE(2), NO, and IL-6 and on the expressions of iNOS and COX-2 in murine macrophages. These anti-inflammatory effects occur through inhibition of MAPK phosphorylation.