Inhibition by licochalcone A, a novel flavonoid isolated from liquorice root, of IL-1beta-induced PGE2 production in human skin fibroblasts

J Pharm Pharmacol. 2005 Dec;57(12):1661-6. doi: 10.1211/jpp.57.12.0017.


Licochalcone A, a novel flavonoid isolated from the root of Glycyrrhiza inflata, has been reported to exhibit anti-inflammatory activity in animal models. In this study, we examined the effect of licochalcone A on the production of chemical mediators such as prostaglandin (PG)E2 and cytokines by interleukin (IL)-1beta in human skin fibroblasts. Licochalcone A (IC50 15.0 nM) inhibited PGE2 production, but not IL-6 and IL-8 production, in response to IL-1beta. NS-398 (IC50 1.6 nM), a COX-2 selective inhibitor, also suppressed the PGE2 production. Furthermore, licochalcone A and NS-398 suppressed PGF(2alpha) production by IL-1beta. However, licochalcone A (1 microM) had no effect on increased levels of cyclooxygenase (COX)-2 mRNA and protein in cells. Dexamethasone (100 nM) not only inhibited PGE2, PGF(2alpha), IL-6 and IL-8 production but also strongly suppressed the expression of COX-2 mRNA and protein. Licochalcone A had no effect on COX-1-dependent PGE2 production, whereas indometacin (100 nM), a dual inhibitor of COX-1 and COX-2, was very effective. These results suggest that licochalcone A induces an anti-inflammatory effect through the inhibition of COX-2-dependent PGE2 production. Furthermore, it appears that the inhibitory effect of licochalcone A on PGE2 production in response to IL-1beta is quite different from that of the steroid.

MeSH terms

  • Base Sequence
  • Chalcone / analogs & derivatives*
  • Chalcone / pharmacology
  • Chalcones
  • Cyclooxygenase 1 / metabolism
  • Cyclooxygenase 2 / genetics
  • Cyclooxygenase 2 / metabolism
  • DNA Primers
  • Dinoprostone / biosynthesis*
  • Fibroblasts / drug effects
  • Fibroblasts / enzymology
  • Fibroblasts / metabolism
  • Glycyrrhiza / chemistry*
  • Humans
  • In Vitro Techniques
  • Interleukin-1 / antagonists & inhibitors*
  • Interleukin-1 / pharmacology
  • Plant Roots / chemistry*
  • RNA, Messenger / genetics
  • Reverse Transcriptase Polymerase Chain Reaction
  • Skin / cytology
  • Skin / drug effects*
  • Skin / enzymology
  • Skin / metabolism


  • Chalcones
  • DNA Primers
  • Interleukin-1
  • RNA, Messenger
  • Chalcone
  • Cyclooxygenase 1
  • Cyclooxygenase 2
  • licochalcone A
  • Dinoprostone