Carvacrol, a component of thyme oil, activates PPARalpha and gamma and suppresses COX-2 expression

J Lipid Res. 2010 Jan;51(1):132-9. doi: 10.1194/jlr.M900255-JLR200.


Cyclooxygenase-2 (COX-2), the rate-limiting enzyme in prostaglandin biosynthesis, plays a key role in inflammation and circulatory homeostasis. Peroxisome proliferator-activated receptors (PPARs) are ligand-dependent transcription factors belonging to the nuclear receptor superfamily and are involved in the control of COX-2 expression, and vice versa. Here, we show that COX-2 promoter activity was suppressed by essential oils derived from thyme, clove, rose, eucalyptus, fennel, and bergamot in cell-based transfection assays using bovine arterial endothelial cells. Moreover, from thyme oil, we identified carvacrol as a major component of the suppressor of COX-2 expression and an activator of PPARalpha and gamma. PPARgamma-dependent suppression of COX-2 promoter activity was observed in response to carvacrol treatment. In human macrophage-like U937 cells, carvacrol suppressed lipopolysaccharide-induced COX-2 mRNA and protein expression, suggesting that carvacrol regulates COX-2 expression through its agonistic effect on PPARgamma. These results may be important in understanding the antiinflammatory and antilifestyle-related disease properties of carvacrol.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Anti-Inflammatory Agents, Non-Steroidal / pharmacology*
  • Cell Line, Tumor
  • Cyclooxygenase 2 / biosynthesis
  • Cyclooxygenase 2 / genetics
  • Cymenes
  • Gas Chromatography-Mass Spectrometry
  • Humans
  • Lipopolysaccharides / pharmacology
  • Monoterpenes / pharmacology*
  • Oils, Volatile / chemistry*
  • PPAR alpha / agonists
  • PPAR gamma / agonists
  • Plant Oils / chemistry*
  • Promoter Regions, Genetic / drug effects
  • Thymus Plant / chemistry*


  • Anti-Inflammatory Agents, Non-Steroidal
  • Cymenes
  • Lipopolysaccharides
  • Monoterpenes
  • Oils, Volatile
  • PPAR alpha
  • PPAR gamma
  • Plant Oils
  • carvacrol
  • Cyclooxygenase 2