title: Influence of Sulforaphane Metabolites on Activities of Human Drug-Metabolizing Cytochrome P450 and Determination of Sulforaphane in Human Liver Cells.
abstract: The influence of metabolites of sulforaphane, natural compounds present in broccoli (Brassica oleracea var. botrytis italica) and in other cruciferous vegetables, on drug-metabolizing cytochrome P450 (CYP) enzymes in human liver microsomes and possible entry of sulforaphane into human hepatic cells were investigated. Metabolites studied are compounds derived from sulforaphane by the mercapturic acid pathway (conjugation with glutathione and by following reactions), namely sulforaphane glutathione and sulforaphane cysteine conjugates and sulforaphane-N-acetylcysteine. Their possible effect on four drug-metabolizing CYP enzymes, CYP3A4 (midazolam 1'-hydroxylation), CYP2D6 (bufuralol 1'-hydroxylation), CYP1A2 (7-ethoxyresorufin O-deethylation), and CYP2B6 (7-ethoxy-4-(trifluoromethyl)coumarin O-deethylation), was tested. Inhibition of four prototypical CYP activities by sulforaphane metabolites was studied in pooled human liver microsomes. Sulforaphane metabolites did not considerably affect biological function of drug-metabolizing CYPs in human liver microsomes except for CYP2D6, which was found to be inhibited down to 73-78% of the original activity. Analysis of the entry of sulforaphane into human hepatocytes was done by cell disruption by sonication, methylene chloride extraction, and modified high-performance liquid chromatography method. The results have shown penetration of sulforaphane into the human hepatic cells.
authors: 1 Department of Pharmacology, Faculty of Medicine and Dentistry, Palacky University Olomouc , Czech Republic .
authors: Alena
authors: A
authors: Vanduchova
authors: 2 Department of Medical Chemistry and Biochemistry, Faculty of Medicine and Dentistry, Palacky University Olomouc , Czech Republic .
authors: Veronika
authors: V
authors: Tomankova
authors: 1 Department of Pharmacology, Faculty of Medicine and Dentistry, Palacky University Olomouc , Czech Republic .
authors: Pavel
authors: P
authors: Anzenbacher
authors: 2 Department of Medical Chemistry and Biochemistry, Faculty of Medicine and Dentistry, Palacky University Olomouc , Czech Republic .
authors: Eva
authors: E
authors: Anzenbacherova
mesh_terms: D001937:Brassica / Q000737:chemistry; D003545:Cysteine / Q000378:metabolism; D019389:Cytochrome P-450 CYP2D6 / Q000187:drug effects / Q000378:metabolism; D065607:Cytochrome P-450 Enzyme Inhibitors / Q000494:pharmacology; D003577:Cytochrome P-450 Enzyme System / Q000187:drug effects* / Q000378:metabolism*; D005978:Glutathione / Q000378:metabolism; D022781:Hepatocytes / Q000378:metabolism; D006801:Humans; D017879:Isothiocyanates / Q000032:analysis* / Q000378:metabolism / Q000494:pharmacology*; D008099:Liver / Q000737:chemistry* / Q000378:metabolism; D008862:Microsomes, Liver / Q000201:enzymology; D013454:Sulfoxides
chemical_list: D065607:Cytochrome P-450 Enzyme Inhibitors; D017879:Isothiocyanates; D013454:Sulfoxides; D003577:Cytochrome P-450 Enzyme System; D019389:Cytochrome P-450 CYP2D6; C016766:sulforaphane; D005978:Glutathione; D003545:Cysteine
keywords: high performance liquid chromatography; inhibition; sulforaphane (cruciferous antioxidants)