Thyme (Thymus vulgaris L.) leaves and its constituents increase the activities of xenobiotic-metabolizing enzymes in mouse liver.
The effects of thyme (Thymus vulgaris L.) leaves and its phenolic compounds, thymol and carvacrol, on the activities of xenobiotic-metabolizing enzymes, i.e., phase I enzymes such as 7-ethoxycoumarin O-deethylase (ECOD) and phase II enzymes such as glutathione S-transferase (GST) and quinone reductase (QR), were investigated. Mice were fed with a diet containing thyme (0.5% or 2.0%) or treated orally with thymol (50-200 mg/kg) or carvacrol (50-200 mg/kg) once a day for 7 successive days, and then the enzyme activities in the livers were analyzed. Dietary administration of 2% thyme caused slightly but significantly higher ECOD, GST, and QR activities by 1.1-1.4-fold. Thymol (200 mg/kg) treatment resulted in significantly higher ECOD, GST, and QR activities by 1.3-1.9-fold, and carvacrol (200 mg/kg) treatment caused significantly higher ECOD, GST, and QR activities by 1.3-1.7-fold. Thymol-treated animals had significantly higher protein levels of GST alpha and GST micro, and carvacrol-treated animals had significantly higher levels of GST micro. These results imply that thyme contains bifunctional inducers (i.e., substances capable of inducing both phase I and phase II enzymes) and that thymol and carvacrol may account for the effects of thyme.
Sasaki
Keiko
K
Laboratory for Molecular/Cellular Biology, Faculty of Pharmaceutical Sciences, Chiba Institute of Science, Choshi-shi, Chiba, Japan. ksasaki@cis.ac.jp
Wada
Keiji
K
Tanaka
Yoshiko
Y
Yoshimura
Teruki
T
Matuoka
Koozi
K
Anno
Takahiko
T
D015660:7-Alkoxycoumarin O-Dealkylase / Q000378:metabolism; D000818:Animals; D015153:Blotting, Western; D000081007:Cymenes; D004305:Dose-Response Relationship, Drug; D004591:Electrophoresis, Polyacrylamide Gel; D005982:Glutathione Transferase / Q000378:metabolism; D008099:Liver / Q000187:drug effects / Q000201:enzymology*; D008297:Male; D051379:Mice; D039821:Monoterpenes / Q000494:pharmacology*; D016660:NAD(P)H Dehydrogenase (Quinone) / Q000378:metabolism; D009929:Organ Size / Q000187:drug effects; D010936:Plant Extracts / Q000494:pharmacology*; D018515:Plant Leaves; D011897:Random Allocation; D013943:Thymol / Q000494:pharmacology*; D046930:Thymus Plant / Q000737:chemistry*; D015262:Xenobiotics / Q000378:metabolism*
D000081007:Cymenes; D039821:Monoterpenes; D010936:Plant Extracts; D015262:Xenobiotics; D013943:Thymol; C073316:carvacrol; D015660:7-Alkoxycoumarin O-Dealkylase; D016660:NAD(P)H Dehydrogenase (Quinone); D005982:Glutathione Transferase