Inhibitors of inducible nitric oxide synthase expression from Artemisia iwayomogi.
Nitric oxide (NO) is an important bioactive agent that mediates a wide variety of physiological and pathophysiological events. NO overproduction by inducible nitric oxide synthase (iNOS) results in severe hypotension and inflammation. This investigation is part of a study to discover new iNOS inhibitors from medicinal plants using a macrophage cell culture system. Two sesquiterpenes (1 and 2) were isolated from Artemisia iwayomogi (Compositae) and were found to inhibit NO synthesis (IC50 3.64 microg/mL and 2.81 microg/mL, respectively) in lipopolysaccharide (LPS)-activated RAW 264.7 cells. Their structures were identified as 3-O-methyl-isosecotanapartholide (1) and iso-secotanapartholide (2). Compounds 1 and 2 inhibited the LPS-induced expression of the iNOS enzyme in the RAW 264.7 cells. The inhibition of NO production via the down regulation of iNOS expression may substantially modulate the inflammatory responses.
College of Pharmacy, Sookmyung Womens University, Seoul 140-742, Korea.
Hanna
H
Ahn
Ji Yeon
JY
Kim
Hwa Jin
HJ
Lee
Yong Kyun
YK
Kim
Jae-Ha
JH
Ryu
D000818:Animals; D019306:Artemisia; D002417:Cattle; D015151:Immunoblotting; D008264:Macrophages / Q000187:drug effects* / Q000276:immunology; D008518:Medicine, East Asian Traditional; D051379:Mice; D019001:Nitric Oxide Synthase / Q000037:antagonists & inhibitors* / Q000187:drug effects; D052247:Nitric Oxide Synthase Type II; D010936:Plant Extracts / Q000302:isolation & purification / Q000494:pharmacology*; D018515:Plant Leaves / Q000737:chemistry* / Q000166:cytology; D010946:Plants, Medicinal / Q000737:chemistry*; D012717:Sesquiterpenes / Q000302:isolation & purification / Q000494:pharmacology*
D010936:Plant Extracts; D012717:Sesquiterpenes; D019001:Nitric Oxide Synthase; D052247:Nitric Oxide Synthase Type II; C496317:Nos2 protein, mouse