Atractylodes japonica suppresses lipopolysaccharide-stimulated expressions of inducible nitric oxide synthase and cyclooxygenase-2 in RAW 264.7 macrophages.

Atractylodes japonica has traditionally been used for the treatment of pain and arthritis. The effect of Atractylodes japonica against lipopolysaccharide-induced inflammation was investigated using reverse transcription-polymerase chain reaction (RT-PCR), nitric oxide detection, and prostaglandin E2 (PGE2) immunoassay in mouse RAW 264.7 macrophages. The aqueous extract of Atractylodes japonica suppressed nitric oxide production and PGE2 synthesis by inhibition of the lipopolysaccharide-stimulated enhancement of inducible nitric oxide synthase and cyclooxygenase-2 mRNAs expressions in RAW 264.7 macrophages. These results suggest that Atractylodes japonica exerts anti-inflammatory and analgesic effects probably by suppression of the inducible nitric oxide synthase and cyclooxygenase-2 expressions.