title: Inhibition of 17alpha-hydroxylase/C17,20-lyase (CYP17) from rat testis by green tea catechins and black tea theaflavins.
abstract: In the course of screening for 17alpha-hydroxylase/C17,20-lyase inhibitors from food ingredients, the methanol soluble fraction of green tea and black tea, which were expected to be rich in catechin and theaflavin content, showed potent inhibitory activity. (-)-Epigallocathechin gallate and theaflavin 3-O-gallate with a pirogallol moiety significantly inhibited C17,20-lyase activity on IC50 values of 24.5 microM and 11.5 microM respectively. They had potent cytotoxicity against human prostate cancer LNCaP cells (IC50=28.1 microM and 37.4 microM).
authors.affiliation: Laboratory of Chemical Biology, Faculty of Agriculture, Iwate University.
authors.forename: Ken-ichi
authors.initials: K
authors.lastname: Kimura
authors.forename: Yoshie
authors.initials: Y
authors.lastname: Itakura
authors.forename: Reika
authors.initials: R
authors.lastname: Goto
authors.forename: Masato
authors.initials: M
authors.lastname: Tojima
authors.forename: Nobumi
authors.initials: N
authors.lastname: Egawa
authors.forename: Makoto
authors.initials: M
authors.lastname: Yoshihama
mesh_terms: D000818:Animals; D044946:Biflavonoids / Q000494:pharmacology*; D002392:Catechin / Q000494:pharmacology*; D003116:Color; D004791:Enzyme Inhibitors / Q000737:chemistry / Q000494:pharmacology*; D012739:Gonadal Steroid Hormones / Q000096:biosynthesis / Q000737:chemistry; D020128:Inhibitory Concentration 50; D008297:Male; D015394:Molecular Structure; D051381:Rats; D013254:Steroid 17-alpha-Hydroxylase / Q000378:metabolism*; D013329:Structure-Activity Relationship; D013662:Tea / Q000737:chemistry*; D013737:Testis / Q000187:drug effects* / Q000201:enzymology*