Modulation of rat and human cytochromes P450 involved in PhIP and 4-ABP activation by an aqueous extract of Phyllanthus orbicularis

Mirle Ferrer, Carles Cristófol, Angel Sánchez-Lamar, Jorge Luís Fuentes, Jordi Barbé, Montserrat Llagostera

Research output: Contribution to journalArticleResearchpeer-review

9 Citations (Scopus)


Phyllanthus orbicularis HBK (Euphorbiaceae) is a medicinal plant, endemic to Cuba, whose aqueous extract has proven antimutagenic effects against hydrogen peroxide and some promutagenic aromatic amines (AAs), in addition to its antiviral properties. In this paper, antimutagenesis of this extract against two carcinogenic AAs, 2-amino-1-methyl-6-phenylimidazo[4,5-b]pyridine (PhIP) and 4-aminobiphenyl (4-ABP) has been studied. Liver microsomal fractions from both induced rats and humans were used to metabolise both procarcinogenic compounds in the Salmonella assay. The plant extract was effective in reducing the mutagenesis of these AAs, activated by both kinds of fractions. The optimal antimutagenic effect was obtained when both AAs were metabolised by human enzymes, with an almost total reduction of 4-ABP mutagenesis and a decrease of about 75% of PhIP mutagenicity. Mutagenicity of both AAs, activated by induced rat fraction, was only decreased by about 50%. Inhibition by plant extract of alkoxyresorufin O-dealkylation activities, dependent on CYP1A, of both fractions was determined. In accordance with the results obtained, the inhibition or modulation of CYP1A subfamily activities, and possibly of CYP1A2, is thought to be the main mechanism of antimutagenesis of the aqueous extract of Phyllanthus orbicularis against 4-ABP and PhIP. © 2003 Elsevier Ireland Ltd. All rights reserved.
Original languageEnglish
Pages (from-to)273-277
JournalJournal of Ethnopharmacology
Issue number2-3
Publication statusPublished - 1 Jan 2004


  • 4-ABP
  • Antimutagenesis
  • CYP1A
  • Cytochromes P450
  • PhIP
  • Phyllanthus orbicularis


Dive into the research topics of 'Modulation of rat and human cytochromes P450 involved in PhIP and 4-ABP activation by an aqueous extract of Phyllanthus orbicularis'. Together they form a unique fingerprint.

Cite this