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.

Vaccinium angustifolium
-degranulation-calcium influx-protein kinase C

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