The 67kDa laminin receptor as a primary determinant of anti-allergic effects of O-methylated EGCG.
Previously we have reported that the O-methylated derivative of (-)-epigallocatechin-3-O-gallate (EGCG), (-)-epigallocatechin-3-O-(3-O-methyl) gallate (EGCG3"Me), possesses anti-allergic activities such as inhibition of histamine release and suppression of the high-affinity IgE receptor (FcepsilonRI) expression. However, the underlying mechanism is still unclear. Recently we have identified the 67kDa laminin receptor (67LR) as a cell-surface receptor that can mediate biological activities of EGCG. Here we show that the suppression of myosin II regulatory light chain (MRLC) phosphorylation through the cell-surface binding to the 67 LR contributes to the inhibitory effect of EGCG3"Me on the histamine release from the human basophilic KU812 cells. The 67LR also mediated the EGCG3"Me-induced suppression of FcepsilonRI expression by reducing ERK1/2 phosphorylation. These results suggest that anti-allergic effects of EGCG3"Me may be triggered by the inhibition of MRLC or ERK1/2 phosphorylation mediated through the cell-surface 67LR.
Fujimura
Yoshinori
Y
Department of Bioscience and Biotechnology, Faculty of Agriculture, Kyushu University, 6-10-1 Hakozaki, Higashi-ku, Fukuoka 812-8581, Japan.
Umeda
Daisuke
D
Yano
Satomi
S
Maeda-Yamamoto
Mari
M
Yamada
Koji
K
Tachibana
Hirofumi
H
D018926:Anti-Allergic Agents / Q000494:pharmacology*; D002392:Catechin / Q000031:analogs & derivatives* / Q000378:metabolism / Q000494:pharmacology; D002460:Cell Line; D006636:Histamine Release / Q000187:drug effects; D006801:Humans; D019950:Mitogen-Activated Protein Kinase 1 / Q000378:metabolism; D048052:Mitogen-Activated Protein Kinase 3 / Q000378:metabolism; D018994:Myosin Light Chains / Q000502:physiology; D024462:Myosin Type II / Q000502:physiology; D017455:Receptors, IgE / Q000096:biosynthesis; D017474:Receptors, Laminin / Q000502:physiology*
D018926:Anti-Allergic Agents; C502447:MS4A2 protein, human; D018994:Myosin Light Chains; D017455:Receptors, IgE; D017474:Receptors, Laminin; C420224:epigallocatechin-3-(3''-O-methyl)gallate; D002392:Catechin; D019950:Mitogen-Activated Protein Kinase 1; D048052:Mitogen-Activated Protein Kinase 3; D024462:Myosin Type II