Research Section InductionofcytochromeP450and/ordetoxicationenzymesby various extracts of rosemary: description of specific patterns P. Debersac a, *,J.-M.Heydel b ,M.-J.Amiot c ,H.Goudonnet b , Y.Artur b ,M.Suschetet a ,M.-H.Siess a a Unite ´ Mixte de Recherche de Toxicologie Alimentaire, Institut National de la Recherche Agronomique-Ecole Nationale Supe ´rieure de Biologie Applique ´e a ` la Nutrition et a ` l’Alimentation, BP 86510, 17 rue Sully, 21065 Dijon Cedex, France b Unite ´ de Biochimie, Pharmacologie, Toxicologie, Faculte ´s de Me ´decine et de Pharmacie, 7 Boulevard Jeanne d ’Arc, BP 87900, 21079 Dijon, France c Laboratoire de Technologie des Produits Ve ´ge ´ taux, Institut National de la Recherche Agronomique, Domaine St Paul, Site Agroparc, 84914 Avignon Cedex 9, France Accepted 16 March 2001 Abstract TheabilityofrosemarytomodulatecytochromeP450(CYP)anddetoxicationenzymesinratliverwasevaluatedbycomparing the effects of dried leaves and leaf extracts with different chemical compositions: essential oil (EO) containing monoterpenes, a di- chloromethaneextract(DCME)containingphenolicditerpenesandawater-solubleextract(WSE)containingphenoliccompounds such as rosmarinic acid and flavonoids. Chemical analyses were done in order to characterize the composition of extracts. Male Wistarratsreceivedtheleavesorextractsofrosemaryintheirdietat0.5%(w/w)for2weeks.Theeffectsofsuchtreatmentswere evaluated for CYP (1A, 2B, 2E1), glutathione S-transferase (GST), NAD(P)H: quinone reductase (QR) and UDP-glucuronosyl- transferase (UGT) activities and on protein levels (immunoblot analyses). Expression of specific UGT isoforms (mRNA semi- quantification by RT-PCR) was measured. Our study reports that EO selectively induced CYP, particularly CYP2B. WSE enhanced both CYP and detoxication enzymes. DCME acted as a monofunctional inducer, inducing GST, QR and UGT, in par- ticularUGT1A6.ConsideringthespecificpatternofinductionobtainedwithDCMEandWSEtreatment,itshouldberelevantto evaluatethechemopreventivepotencyoftheseextractsoncarcinogenesisinanimalmodels. # 2001ElsevierScienceLtd.Allrights reserved. Keywords: Rosemaryextracts;CytochromeP450;Glutathione S-transferase; NAD(P)H: quinone reductase; UDP-glucuronosyltransferase; Rat 1. Introduction An increasing number of studies demonstrate the ability of Rosmarinus officinalis to inhibit the carcino- genicity of structurally diverse chemicals in animal models (Singletary et al., 1996). A mechanism that may be responsible for impairment of the initiation stage of carcinogenesis by rosemary extracts is the direction of the metabolism of chemical carcinogens towards the generation of inactive metabolites and/or detoxication of the reactive intermediates through conjugation. Indeed, feeding animals with a diet supplemented with rosemary extracts resulted in increases in hepatic glu- tathione S-transferase (GST) and NAD(P)H: quinone reductase (QR) activities (Singletary, 1996; Singletary and Rokusek, 1997). In most published studies, the chemical composition or the technology applied to the extracts of rosemary is not highlighted; therefore it is difficult to ascribe the inducing effects to specific com- ponents.Besidesvolatilemoleculessuchasmonoterpenes, rosemary leaves contain antioxidant compounds such as phenolic diterpenes, phenolic acids and flavonoids. Phe- nolic diterpenes such as carnosol or carnosic acid have beenshowntomodifyxenobioticmetabolizingenzymes (XME);carnosolenhancedGSTinratliver(Singletary, 0278-6915/01/$ - see front matter # 2001 Elsevier Science Ltd. All rights reserved. PII:S0278-6915(01)00034-5 Food and Chemical Toxicology 39 (2001) 907–918 www.elsevier.com/locate/foodchemtox Abbreviations: CDNB, 1-chloro-2,4dinitrobenzene; CYP, cyto- chrome P450; DCM(E), dichloromethane (extract of rosemary); EO, essential oil; EQ, ethoxyquin; EROD, ethoxyresorufin O-deethylase; GSH, reduced glutathione; GST, glutathione S-transferase; L, leaves of rosemary; MROD, methoxyresorufin O-demethylase; OPZ, olti- praz; PNPH, p-nitrophenol hydroxylase; PROD, pentoxyresorufin O- dealkylase; QR, NAD(P)H: quinone reductase; RA, rosmarinic acid; UGT, UDP-glucuronosyltransferase; WSE, water-soluble extract; XME,xenobioticmetabolizingenzymes. * Correspondingauthor.Tel.:+33-380-69-36-25;fax:+33-380-69- 32-25. E-mail address: siess@dijon.inra.fr (M.-H. Siess).