PT  - JOURNAL ARTICLE
AU  - Yanyan Cui
AU  - Catharina Y.W. Ang
AU  - Richard D. Beger
AU  - Thomas M. Heinze
AU  - Lihong Hu
AU  - Julian Leakey
TI  - IN VITRO METABOLISM OF HYPERFORIN IN RAT LIVER MICROSOMAL SYSTEMS
AID  - 10.1124/dmd.32.1.28
DP  - 2004 Jan 01
TA  - Drug Metabolism and Disposition
PG  - 28--34
VI  - 32
IP  - 1
4099  - http://dmd.aspetjournals.org/content/32/1/28.short
4100  - http://dmd.aspetjournals.org/content/32/1/28.full
SO  - Drug Metab Dispos2004 Jan 01; 32
AB  - Hyperforin is an important active component of St. John's wort (Hypericum perforatum) that has been suggested to be responsible for the St. John's wort antidepressive effects and herbal-drug interactions. In this study, the in vitro metabolism profile of hyperforin was investigated using liver microsomes from male and female Sprague-Dawley rats, with or without induction by phenobarbital or dexamethasone. Four major Phase I metabolites, named 19-hydroxyhyperforin, 24-hydroxyhyperforin, 29-hydroxyhyperforin, and 34-hydroxyhyperforin, were isolated by high performance liquid chromatography and identified by mass spectrometry and NMR. Results suggest that hydroxylation is a major biotransformation of the hyperforin pathway in rat liver and that inducible cytochrome P450 3A (CYP450 3A) and/or CYP2B may be the major cytochrome P450 isoforms catalyzing these hydroxylation reactions. The American Society for Pharmacology and Experimental Therapeutics