Anti-inflammatory Effects of Amomum compactum on RAW 264.7 cells via induction of heme oxygenase-1

Amomum compactum is commonly used in Korean traditional medicine. In this study, we demonstrate that A. compactum ethanolic extract (ACEE) has anti-inflammatory effects in a lipopolysaccharide-induced RAW 264.7 cell model of inflammation. In this system, ACEE prominently inhibited the production of nitric oxide (NO), prostaglandin E-2 (PGE(2)), interleukin (IL)-6 and tumor necrosis factor (TNF)-alpha, and inhibited the protein expression of inducible nitric oxide synthase and cyclooxygenase-2. Furthermore, ACEE treatment inhibited the translocation of nuclear factor-kappaB (NF-kappa B) and the degradation of inhibitory factor-kappaB alpha, but enhanced the expression of heme oxygenase (HO)-1 and the nuclear translocation of nuclear factor-erythroid 2 (Nrf2). Treatment with tin protoporphyrin IX dichloride (SnPP), a selective HO-1 inhibitor, reversed the ACEE-induced suppression of NO production, suggesting that the induction of HO-1 is involved in the suppression of NO, TNF-alpha, and IL-6 production by ACEE. Taken together, these results suggest that ACEE have anti-inflammatory effects occurring through HO-1 induction, which leads to suppression of the blocking NF-kappa B.