Inhibitory effect of ginsenoside Rb1 and compound K on NO and prostaglandin E2 biosyntheses of RAW264.7 cells induced by lipopolysaccharide

Biol Pharm Bull. 2005 Apr;28(4):652-6. doi: 10.1248/bpb.28.652.


In this study, the antiinflammatory activities of ginsenoside Rb1, which is a main constituent of the root of Panax ginseng (Araliaceae), and of its metabolite compound K, as produced by human intestinal bacteria, on lipopolysaccharide (LPS)-induced RAW264.7 cells were investigated. Compound K potently inhibited the production of NO and prostaglandin E2 in LPS-induced RAW 264.7 cells, with IC(50) values of 0.012 and 0.004 mM, respectively. Compound K also reduced the expression levels of the inducible NO synthase (iNOS) and COX-2 proteins and inhibited the activation of NF-kB, a nuclear transcription factor. Compound K inhibited the NO level produced by iNOS enzyme activity in a cell-free system, but did not inhibit COX-1 and 2 activities. When ginsenoside Rb1 was orally administered to rats, compound K, but not ginsenoside Rb1, were excreted in their urine. These findings suggest that ginsenoside Rb1 can be transformed to compound K by intestinal bacteria, and compound K may be effective against inflammation.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Animals
  • Anti-Inflammatory Agents / pharmacology*
  • Cell Line
  • Cyclooxygenase 2
  • Dinoprostone / biosynthesis*
  • Gene Expression / drug effects
  • Ginsenosides / pharmacokinetics
  • Ginsenosides / pharmacology*
  • Ginsenosides / urine
  • Lipopolysaccharides / pharmacology*
  • Male
  • NF-kappa B / metabolism
  • Nitric Oxide / biosynthesis*
  • Nitric Oxide Synthase / metabolism
  • Nitric Oxide Synthase Type II
  • Prostaglandin-Endoperoxide Synthases / metabolism
  • Rats
  • Rats, Sprague-Dawley


  • Anti-Inflammatory Agents
  • Ginsenosides
  • Lipopolysaccharides
  • NF-kappa B
  • Nitric Oxide
  • ginsenoside Rb1
  • ginsenoside M1
  • Nitric Oxide Synthase
  • Nitric Oxide Synthase Type II
  • Nos2 protein, rat
  • Cyclooxygenase 2
  • Prostaglandin-Endoperoxide Synthases
  • Dinoprostone