In relation to anti-inflammatory agents from medicinal plants, we have isolated three compounds from Atractylodes macrocephala; 1, 2-[(2E)-3,7-dimethyl-2,6-octadienyl]-6-methyl-2, 5-cyclohexadiene-1, 4-dione; 2, 1-acetoxy-tetradeca-6E,12E-diene-8, 10-diyne-3-ol; 3, 1,3-diacetoxy-tetradeca-6E, 12E-diene-8, 10-diyne. Compounds 1-3 showed concentration-dependent inhibitory effects on production of nitric oxide (NO) and prostaglandin E2 (PGE2) in lipopolysaccharide (LPS)-activated RAW 264.7 macrophages. Western blotting and RT-PCR analyses demonstrated that compounds 1-3 suppressed the protein and mRNA levels of inducible nitric oxide synthase (iNOS) and cyclooxygenase-2 (COX-2). Furthermore, compounds 1-3 inhibited transcriptional activity of nuclear factor-κB (NF-κB) and nuclear translocation of NF-κB in LPS-activated RAW 264.7 cells. The most active compound among them, compound 1, could reduce the mRNA levels of pro-inflammatory cytokines (IL-1β, IL-6 and TNF-α) and suppress the phosphorylation of MAPK including p38, JNK, and ERK1/2. Taken together, these results suggest that compounds 1-3 from A. macrocephala can be therapeutic candidates to treat inflammatory diseases.
Keywords: Atractylodes macrocephala; cyclooxygenase-2; inducible nitric oxide synthase; nitric oxide; nuclear factor-κB; prostaglandin E2.