Article

Inhibitory effects of blueberry root methanolic extract on degranulation in KU812F cells

Food science and biotechnology (Impact Factor: 0.7). 10/2010; 19(5):1185-1189. DOI: 10.1007/s10068-010-0169-9

ABSTRACT The effect of blueberry (Vaccinium angustifolium) root methanolic extract (BRM) on the A23187 plus phorbol myristate acetate (PMA)-induced degranulation in human basophilic
KU812F cells was investigated. The total phenolic content (TPC) was 170±1.9 mg gallic acid equivalents (GAE)/g BRM. BRM reduced
levels of histamine and β-hexosaminidase released from stimulated KU812F cells. Intracellular calcium concentration ([Ca2+]i) were determined by spectrofluorometric analysis using Fura 2-AM was found to be reduced by BRM with dose-dependent manner.
Moreover, Western blot analysis revealed that protein kinase C (PKC) translocation was inhibited by BRM with dose-dependent
manner. These results indicated that BRM inhibited histamine and β-hexosaminidase through the suppression of Ca2+ influx and PKC translocation. Therefore, we suggest that BRM is potent inhibitor of degranulation in mast cells and basophils,
and may be useful in preventing the allergic reactions.

Keywords
Vaccinium angustifolium
-degranulation-calcium influx-protein kinase C

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