A difference between epigallocatechin-3-gallate and epicatechin-3-gallate on anti-allergic effect is dependent on their distinct distribution to lipid rafts

Issue title: The Proceedings of the 3rd International Conference on Food Factors (ICoFF 03)

Article type: Research Article

Authors: Fujimura, Yoshinori | Tachibana, Hirofumi | Kumai, Rie | Yamada, Koji

Affiliations: Department of Bioscience and Biotechnology, Faculty of Agriculture, Kyushu University, Fukuoka 812-8581, Japan

Note: [] Address for correspondence: Hirofumi Tachibana, 6-10-1 Hakozaki, Higashi-ku, Fukuoka 812-8581, Japan. Tel./Fax: +81 92 642 3008; E-mail: [email protected]

Abstract: The high-affinity IgE receptor FcεRI expresses on the cell surface of mast cells and basophils, which is the key molecule in allergic reactions. We previously found that the major green tea catechin, (-)-epigallocatechin-3-O-gallate (EGCG), has the suppressive effect of the FcεRI expression in the human basophilic KU812 cells, whereas (-)-epicatechin-3-O-gallate (ECG) has not. For understanding the mechanism of catechins, interactions of catechins with cellular membranes were investigated. Both catechins were shown to bind the cell surface of KU812 cells by surface plasmon resonance assay. EGCG highly associated with cholesterol- and sphingolipid-enriched membrane microdomains known as lipid rafts. On the other hand, the level of ECG in rafts was lower than that of EGCG, suggesting that the association with lipid rafts may have an important role in the FcεRI-suppressive effect of catechins.

Keywords: high-affinity IgE receptor, allergy, EGCG, ECG, tea catechin, lipid rafts, basophils

Journal: BioFactors, vol. 21, no. 1-4, pp. 133-135, 2004