Effects of extract of Ginkgo biloba leaves and its constituents on carcinogen-metabolizing enzyme activities and glutathione levels in mouse liver

• Published in: Life sciences (1973) 2002-02, Vol.70 (14), p.1657-1667
• Main Authors: Sasaki, Keiko, Hatta, Shinichi, Wada, Keiji, Ueda, Naomi, Yoshimura, Teruki, Endo, Tetsuya, Sakata, Masakatsu, Tanaka, Takuji, Haga, Masanobu
• Format: Article
• Language: English
• Subjects: Animals; Bilobalide; Blotting, Western; Carcinogens - metabolism; Cyclopentanes - pharmacology; Diterpenes; DT-diaphorase; Furans - pharmacology; Ginkgo biloba - chemistry; Ginkgo biloba L; Ginkgolides; Glutathione; Glutathione - metabolism; Glutathione S-transferase; Glutathione Transferase - metabolism; Isoenzymes - metabolism; Lactones - pharmacology; Liver - drug effects; Liver - enzymology; Liver - metabolism; Mice; NAD(P)H Dehydrogenase (Quinone) - metabolism; Plant Extracts - pharmacology; Plant Leaves - chemistry
• ISSN: 0024-3205; 1879-0631
• DOI: 10.1016/S0024-3205(01)01557-0

The effects of a standardized extract of Ginkgo biloba L. leaves (EGb) and its terpene constituents, bilobalide and ginkgolides, on the activities of detoxification enzymes, i.e., glutathione S-transferases (GSTs) and DT-diaphorase, and glutathione contents, were investigated in the mouse liver. Oral treatment with EGb (100–1000 mg/kg) and bilobalide (10–30 mg/kg) once a day for 4 days caused a dose-dependent elevation in GST activity. Ginkgolide A (30 mg/kg, for 4 days) also significantly elevated GST activity, whereas ginkgolide B and ginkgolide C at the same dose had no effects. EGb significantly increased the protein level of GST π, and bilobalide significantly increased those of GST α and GST μ. Moreover, EGb-treatment and bilobalide-treatment caused significant elevations in DT-diaphorase activity and in hepatic glutathione contents.