Black Tea Theaflavins Suppress Dioxin-Induced Transformation of the Aryl Hydrocarbon Receptor
-
- FUKUDA Itsuko
- Division of Life Science, Graduate School of Science and Technology, Kobe University
-
- SAKANE Iwao
- Central Research Institute, Ito En, Ltd.
-
- YABUSHITA Yoshiyuki
- Department of Biofunctional Chemistry, Faculty of Agriculture, Kobe University
-
- SAWAMURA Shin-ichi
- Central Research Institute, Ito En, Ltd.
-
- KANAZAWA Kazuki
- Division of Life Science, Graduate School of Science and Technology, Kobe University Department of Biofunctional Chemistry, Faculty of Agriculture, Kobe University
-
- ASHIDA Hitoshi
- Division of Life Science, Graduate School of Science and Technology, Kobe University Department of Biofunctional Chemistry, Faculty of Agriculture, Kobe University
Search this article
Abstract
Dioxins cause various adverse effects through transformation of aryl hydrocarbon receptor (AhR). In this study, we investigated whether black tea extract and its components, theaflavins, suppress AhR transformation in vitro. First, we confirmed that black tea extract strongly suppressed AhR transformation compared to green and oolong tea, although the catechin contents did not change significantly among the extracts. Then we isolated four theaflavins as active compounds from black tea leaves. They suppressed 1 nM 2,3,7,8-tetrachlorodibenzo-p-dioxin (TCDD)-induced AhR transformation in a dose-dependent manner. The IC50 values of theaflavin, theaflavin-3-gallate, theaflavin-3′-gallate, and theaflavin-3,3′-digallate (Tfdg) were 4.5, 2.3, 2.2, and 0.7 μM, respectively. The suppressive effect of Tfdg was observed not only by pre-treatment but also by post-treatment. This suggests that theaflavins inhibit the binding of TCDD to the AhR and also the binding of the transformed AhR to the specific DNA-binding site as putative mechanisms.
Journal
-
- Bioscience, Biotechnology, and Biochemistry
-
Bioscience, Biotechnology, and Biochemistry 69 (5), 883-890, 2005
Japan Society for Bioscience, Biotechnology, and Agrochemistry
- Tweet
Details 詳細情報について
-
- CRID
- 1390282681451509504
-
- NII Article ID
- 130000030316
-
- NII Book ID
- AA10824164
-
- ISSN
- 13476947
- 09168451
-
- NDL BIB ID
- 7322337
-
- PubMed
- 15914905
-
- Text Lang
- en
-
- Data Source
-
- JaLC
- NDL
- Crossref
- PubMed
- CiNii Articles
- KAKEN
-
- Abstract License Flag
- Disallowed