20( S)-Protopanaxatriol, one of ginsenoside metabolites, inhibits inducible nitric oxide synthase and cyclooxygenase-2 expressions through inactivation of nuclear factor-κB in RAW 264.7 macrophages stimulated with lipopolysaccharide

• Published in: Cancer letters Vol. 205; no. 1; pp. 23 - 29
• Main Authors: Oh, G.S, Pae, H.O, Choi, B.M, Seo, E.A, Kim, D.H, Shin, M.K, Kim, J.D, Kim, J.B, Chung, H.T
• Format: Journal Article
• Language: English
• Published: Elsevier Ireland Ltd 08.03.2004
• Subjects: 20( S)-Protopanaxatriol; Chemoprevention; Cyclooxygenase-2; Ginsenoside; Inducible nitric oxide synthase; Inflammation; Nuclear factor-κB; Panax ginseng; Inducible nitric oxide synthase; Chemoprevention; Inflammation; Cyclooxygenase-2; Nuclear factor-κB; Panax ginseng; Ginsenoside; 20( S)-Protopanaxatriol
• ISSN: 0304-3835; 1872-7980
• DOI: 10.1016/j.canlet.2003.09.037

Ginsenosides from Panax ginseng are metabolized by human intestinal bacteria after oral administration of ginseng extract. 20( S)-Protopanaxatriol (PPT) is one of the major metabolites of ginsenosides. Inducible nitric oxide synthase (iNOS) and cyclooxygenase-2 (COX-2) are important enzymes that mediate inflammatory processes. Improper up-regulation of iNOS and/or COX-2 has been associated with the pathogenesis of inflammatory diseases and certain types of human cancers. Here, we investigated whether PPT could modulate iNOS and COX-2 expressions in RAW 264.7 macrophages stimulated with the endotoxin lipopolysaccharide (LPS). We found that PPT blocked the increase in LPS-induced iNOS and COX-2 expressions through inactivation of nuclear factor-κB by preventing I-κBα phosphorylation and degradation. Thus, it may be possible to develop PPT as a useful agent for chemoprevention of cancer or inflammatory diseases.