Anti-inflammatory components isolated from Atractylodes macrocephala in LPS-induced RAW264.7 macrophages and BV2 microglial cells

Abstract The phytochemical investigation on the methanol extract of the rhizomes of Atractylodes macrocephala resulted in the discovery of one new compound 9α-hydroxyatractylenolide ( 1 ) and 21 known compounds including atractylone ( 2 ), 3β-acetoxyatractylon ( 3 ), atractylenolide I ( 4 ), atractylenolide II ( 5 ), 8-epiasterolid (6), atractylenolide III ( 7 ), atractylenolide VII ( 8 ), 8-epiatractylenolide III ( 9 ), eudesm-4(15)-ene-7α,11-diol ( 10 ), linoleic acid ( 11 ), myristic acid ( 12 ), 3- O -caffeoyl-1-methyquinic acid ( 13 ), (2 E ,8 E ,10 E )-tetradecatriene-4,6-diyne-1,14-diol ( 14 ), 14-aceroxy-12-senecioyloxytetradeca-2 E ,8 Z ,10 E -trien-4,6-diyn-1-ol ( 15 ), isoscopoletin ( 16 ), caffeic acid ( 17 ), protocatechic acid ( 18 ), 3- O -caffeoylquinic acid ( 19 ), 4- O -caffeoylquinic acid ( 20 ), 1,5-di- O -caffeoylquinic acid ( 21 ), and nicotinic acid ( 22 ). Their structures were identified using nuclear magnetic resonance (NMR) and mass spectroscopy, and by comparison with previously published data. Compounds 4 , 5 , 6 , 8 , and 10 – 22 significantly inhibited lipopolysaccharide (LPS)-induced nitric oxide (NO) production in RAW264.7 macrophages, and compounds 4 , 5 , 6 , 16 , and 17 showed those responses in BV2 microglial cells. Especially, compound 6 showed the second-best effect, and inhibited the LPS-induced production of prostaglandin E2 (PGE 2 ), the protein expression of inducible nitric oxide synthase (iNOS) and cyclooxygenase (COX)-2, and the production of cytokines including interleukin (IL)-1β, IL-6, and tumor necrosis factor (TNF)-α in both cells. These inhibitory effects were mediated by the inactivation of nuclear factor kappa B (NF-κB) signaling pathway.