Pseudoguaianolides isolated from Inula britannica var. chinenis as inhibitory constituents against inducible nitric oxide synthase.
Three pseudoguaianolide type sesquiterpenes, bigelovin (1), 2,3-dihydroaromaticin (2), and ergolide (3) were isolated as inhibitory constituents against inducible nitric oxide synthase (iNOS) from the flowers of Inula britannica var. chinensis. Bigelovin (1) exhibited a highly potent inhibitory activity on lipopolysaccharide (LPS)-induced iNOS in murine macrophage RAW 264.7 cells with an IC50 value of 0.46 mM, which is about 8 times more potent than the known selective inhibitor of iNOS, L-N6-(1-iminoethyl)lysine (IC50 3.49 microM). 2,3-Dihydroaromaticin (2) and ergolide (3) also exhibited potent inhibitory activities on LPS-induced iNOS with IC50 values of 1.05 and 0.69 microM, respectively.
Lee
Hyun-Tai
HT
Natural Products Chemistry Laboratory, College of Pharmacy, Ewha Womans University, Seoul, Korea.
Yang
Seung-Won
SW
Kim
Kyeong Ho
KH
Seo
Eun-Kyoung
EK
Mar
Woongchon
W
D000818:Animals; D004791:Enzyme Inhibitors / Q000494:pharmacology*; D038143:Inula / Q000737:chemistry*; D051379:Mice; D019001:Nitric Oxide Synthase / Q000037:antagonists & inhibitors*; D052247:Nitric Oxide Synthase Type II; D012717:Sesquiterpenes / Q000494:pharmacology*
D004791:Enzyme Inhibitors; D012717:Sesquiterpenes; D019001:Nitric Oxide Synthase; D052247:Nitric Oxide Synthase Type II; C496317:Nos2 protein, mouse