Researchers have found that six essential oils –from thyme, clove, rose, eucalyptus, fennel and bergamot—can suppress the inflammatory COX-2 enzyme, in a manner similar to resveratrol, the chemical linked with the health benefits of red wine. They also identified that the chemical carvacrol was primarily responsible for this suppressive activity.[i]
Essential oils from plants have long been a component of natural remedies, and even today are used for their aromatherapy, analgesic (e.g. cough drops), or antibacterial properties. The exact way they work is not completely understood. However, Hiroyasu Inoue and colleagues in Japan believed that many essential oils might target COX-2 much like compounds in wine and tea.
So, they screened a wide range of commercially available oils and identified six (thyme, clove, rose, eucalyptus, fennel and bergamot) that reduced COX-2 expression in cells by at least 25%. Of these, thyme oil proved the most active, reducing COX-2 levels by almost 75%.
When Inoue and colleagues analyzed thyme oil, they found that the major component –carvacrol– was the primary active agent; in fact when they use pure carvacrol extracts in their tests COX-2 levels decreased by over 80%.
Cavacrol is also a component of Oregano oil and may account for some of the benefits found when oregano oil is used to treat dysbiosis, for as well as being a potent antimicrobial its active ingredients may also limit inflammation in the local tissues.[ii]
Moreover, from thyme oil, we identified carvacrol as a major component of the suppressor of COX-2 expression and an activator of PPARα and PPARγ-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 PPARγ. These results may be important in understanding the antiinflammatory and antilifestyle-related disease properties of carvacrol.
[i] Hotta M, Nakata R, Katsukawa M, Hori K, Takahashi S, Inoue H.J Carvacrol, a component of thyme oil, activates PPARalpha and gamma and suppresses COX-2 expression.Lipid Res. 2010 Jan;51(1):132-9. View Abstract