Anti-allergic effect of the flavonoid myricitrin from Myrica rubra leaf extracts in vitro and in vivo.

Department of Cooperative Medical Research, Collaboration Center, Shimane University, Izumo, Japan.
Natural product research (Impact Factor: 1.23). 02/2011; 25(4):374-80. DOI: 10.1080/14786411003774320
Source: PubMed

ABSTRACT Flavonoids are ingested by the general population as anti-oxidant and anti-inflammatory agents. In this study, we investigated the effects of myricitrin, a flavonoid rich in Myrica rubra leaf, upon anti-inflammatory action. Myrica rubra leaf extracts inhibited pro-inflammatory TNFα production in a macrophage cell line, Raw264.7 cells. We observed that the serum IgE levels in the leaf extract-treated DO11.10, a mouse allergy model, were down-regulated. HPLC was performed to demonstrate that M. rubra leaf extracts contain a large amount of myricitrin. We observed an inhibitory effect of HPLC-purified myricitrin on TNFα production in Raw264.7 cells. Thus, myricitrin may be of potential interest in the management of inflammatory conditions.

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