Influence of CYP2D6 polymorphism on 3,4-methylenedioxymethamphetamine (‘Ecstasy’) cytotoxicity

Carmo, Helena^a; Brulport, Marc^c; Hermes, Matthias^c; Oesch, Franz^g; Silva, Renata^a; Ferreira, Luísa M.^b; Branco, Paula S.^b; Boer, Douwe de^h; Remião, Fernando^a; Carvalho, Félix^a; Schön, Michael R.^d; Krebsfaenger, Niels^e; Doehmer, Johannes^f; Bastos, Maria de Lourdes^a; Hengstler, Jan G.^c

Author Information

^aREQUIMTE, Toxicology Department, Faculty of Pharmacy, University of Porto, Porto

^bREQUIMTE/CQFB, Chemistry Department, Faculty of Science and Technology, University Nova of Lisboa, Monte de Caparica, Portugal

^cCentre for Toxicology

^dDepartment of Surgery, University of Leipzig, Leipzig

^eSchwarz Biosciences GmbH, Department of Pharmacology and Toxicology, Monheim

^fGenPharmTox BioTech AG, D-Planegg/Martinsried

^gInstitute of Toxicology, University of Mainz, Mainz, Germany

^hDepartment of Clinical Chemistry, University Hospital Maastricht, Maastricht, The Netherlands

Correspondence and requests for reprints to Helena Carmo, Toxicology Department, Faculty of Pharmacy, University of Porto, Rua Aníbal Cunha, 164, 4050-047 Porto, Portugal.

Tel: +351222078979; fax: +351222003977; e-mail:[email protected]

Sponsorship: This work was supported by Fundação Para a Ciência e a Tecnologia (POCI/SAU-FCF/57187/2004), by REQUIMTE Associated Laboratory, by a CRUP/DAAD grant (reference A-5/04) and by the German Federal Ministry of Education and Research (BMBF), funding priority HepatoSys, Systems Biology of the Hepatocyte.

Received 18 April 2006 Accepted 22 June 2006

Pharmacogenetics and Genomics16(11):p 789-799, November 2006. |DOI:10.1097/01.fpc.0000230419.05221.fc

Abstract

Objectives

Remarkable interindividual differences in 3,4-methylenedioxymethamphetamine (‘Ecstasy’)-mediated toxicity have been reported in humans. Therefore, we tested whether CYP2D6 or its variant alleles as well as CYP3A4 influence the susceptibility to 3,4-methylenedioxymethamphetamine.

Methods

3,4-Methylenedioxymethamphetamine cytotoxicity was determined in V79 cells expressing human wild-type CYP2D6 (CYP2D6*1), the low-activity alleles CYP2D6*2, *9, *10, and *17, as well as human CYP3A4. Metabolites of 3,4-methylenedioxymethamphetamine formed by the different cell lines were quantified by high-performance liquid chromatography/electrochemical detector.

Results

Toxicity of 3,4-methylenedioxymethamphetamine was clearly increased in cells expressing CYP2D6*1 compared with the parental cells devoid of CYP-dependent enzymatic activity. Toxicity in V79 CYP2D6*1 cells was also higher than in V79 cell lines expressing the low-activity alleles CYP2D6*2, *9, *10, or *17. In contrast to CYP2D6, the CYP3A4 isoenzyme did not enhance 3,4-methylenedioxymethamphetamine toxicity. Formation of the oxidative 3,4-methylenedioxymethamphetamine metaboliteN-methyl-α-methyldopamine was greatly enhanced in V79 cell line transfected with CYP2D6*1 compared to all other cell lines. The increase in the cytotoxic effects of 3,4-methylenedioxymethamphetamine observed in this cell line was therefore suspected to be a consequence of the production of this metabolite. This was further investigated by testing the cytotoxicity ofN-methyl-α-methyldopamine to the control cell line. The results confirmed our hypothesis as the metabolite proved to be more than 100-fold more toxic than the parent compound 3,4-methylenedioxymethamphetamine.

Conclusions

CYP2D6*1 mediates 3,4-methylenedioxymethamphetamine toxicity via formation ofN-methyl-α-methyldopamine. Therefore, it will be important to investigate whether CYP2D6 ultrarapid metabolizers are overrepresented in the cases of 3,4-methylenedioxymethamphetamine intoxications.