title: Induction of chemoprotective phase 2 enzymes by ginseng and its components.
abstract: Phase 2 detoxification enzymes protect against carcinogenesis and oxidative stress. Ginseng ( PANAX spp.) extracts and components were assayed for inducer activity of NQO1 (quinone reductase), a phase 2 enzyme, in Hepa1c1c7 cells. Ginseng extracts were analyzed for ginsenosides and panaxytriol. Korean red PANAX GINSENG extracts demonstrated the most potent phase 2 enzyme induction activity (76,900 U/g dried rhizome powder and 27,800 U/g for two similar preparations). The ginsenoside-enriched HT-1001 American ginseng ( PANAX QUINQUEFOLIUS) extract was the next most potent inducer, with activity of 15,900 U/g, followed by raw American ginseng root with activity of 8700 U/g. Neither a polysaccharide-enriched extract of American ginseng nor a commercial white PANAX GINSENG preparation showed any inducer activity. Pure ginsenosides showed no inducer activity. Protopanaxadiol and protopanaxatriol, deglycosylated ginsenoside metabolic derivatives, showed potent induction activity (approximately 500,000 U/g each). Synthetic panaxytriol was over 10-fold more potent (induction potency 5,760,000 U/g). There was no correlation between ginsenoside content and phase 2 enzyme induction. The most potent inducing red ginseng extract also had the highest panaxytriol content, 120.8 microg/g. We found that ginseng induced NQO1 and that polyacetylenes are the most active components.
authors.affiliation: Division of Clinical Pharmacology, Department of Medicine, Johns Hopkins University, Baltimore, MD, USA.
authors.forename: Lawrence S
authors.initials: LS
authors.lastname: Lee
authors.forename: Katherine K
authors.initials: KK
authors.lastname: Stephenson
authors.forename: Jed W
authors.initials: JW
authors.lastname: Fahey
authors.forename: Teresa L
authors.initials: TL
authors.lastname: Parsons
authors.forename: Paul S
authors.initials: PS
authors.lastname: Lietman
authors.forename: Adriana S
authors.initials: AS
authors.lastname: Andrade
authors.forename: Xiaoguang
authors.initials: X
authors.lastname: Lei
authors.forename: Heedong
authors.initials: H
authors.lastname: Yun
authors.forename: Gaik H
authors.initials: GH
authors.lastname: Soon
authors.forename: Ping
authors.initials: P
authors.lastname: Shen
authors.forename: Samuel
authors.initials: S
authors.lastname: Danishefsky
authors.forename: Charles
authors.initials: C
authors.lastname: Flexner