title: Differential induction of the expression of GST subunits by geniposide in rat hepatocytes.
abstract: Geniposide, an iridoid glycoside isolated from the fruit of Gardenia jasminoides Ellis, has the biological capabilities of detoxication, antioxidation, and anticarcinogenesis. In this study, the mechanism of geniposide affecting the GST (glutathione S-transferase) system was investigated. Primary cultured rat hepatocytes were treated with geniposide and examined for total GST activity and expression of GST subunits. The results showed that the geniposide-induced GST activity was dose and time dependent. Western blotting data demonstrated that geniposide induced increased protein levels of GSTM1 and GSTM2 (approximately 1.7- and 1.8-fold of control, respectively), but did not increase those of GSTA1. The corresponding transcripts levels were confirmed by RT-PCR. Using PD98059, the effect of geniposide was verified to be via the MEK pathway. The results suggest that geniposide possesses a potential for detoxication by inducing GST activity via increasing the transcription of GSTM1 and GSTM2.
authors.affiliation: Division of Gastroenterology, Department of Internal Medicine, Armed Forces Taichung General Hospital, Taichung, Taiwan.
authors.forename: Wu-Hsien
authors.initials: WH
authors.lastname: Kuo
authors.forename: Chau-Jong
authors.initials: CJ
authors.lastname: Wang
authors.forename: Shun-Chieh
authors.initials: SC
authors.lastname: Young
authors.forename: Yuan-Chang
authors.initials: YC
authors.lastname: Sun
authors.forename: Yi-Jun
authors.initials: YJ
authors.lastname: Chen
authors.forename: Fen-Pi
authors.initials: FP
authors.lastname: Chou
mesh_terms: D000818:Animals; D002478:Cells, Cultured; D004305:Dose-Response Relationship, Drug; D004365:Drugs, Chinese Herbal; D004790:Enzyme Induction / Q000187:drug effects* / Q000235:genetics; D005419:Flavonoids / Q000494:pharmacology; D005638:Fruit; D005982:Glutathione Transferase / Q000037:antagonists & inhibitors / Q000096:biosynthesis* / Q000235:genetics; D006027:Glycosides / Q000008:administration & dosage / Q000493:pharmacokinetics / Q000627:therapeutic use; D006505:Hepatitis / Q000188:drug therapy; D022781:Hepatocytes / Q000187:drug effects* / Q000201:enzymology*; D039823:Iridoids / Q000008:administration & dosage / Q000493:pharmacokinetics* / Q000627:therapeutic use*; D007527:Isoenzymes / Q000096:biosynthesis; D008297:Male; D010936:Plant Extracts; D011714:Pyrans; D012333:RNA, Messenger / Q000378:metabolism; D051381:Rats; D017207:Rats, Sprague-Dawley; D019666:Rubiaceae; D013997:Time Factors
chemical_list: D004365:Drugs, Chinese Herbal; D005419:Flavonoids; D005982:Glutathione Transferase; D006027:Glycosides; D039823:Iridoids; D007527:Isoenzymes; D010936:Plant Extracts; D011714:Pyrans; D012333:RNA, Messenger; C007835:geniposide; C412602:glutathione S-transferase Mu 2; C093973:2-(2-amino-3-methoxyphenyl)-4H-1-benzopyran-4-one