| Abstract |
Objective: To evaluate the immunomodulatory effects of rice
bran hydrolysates on cultured immune cells and their underlying
mechanism.
Methods: Rice bran hydrolysates were prepared from pigmented
rice (Oryza sativa L.) by hydrothermolysis and protease digestion.
Rice bran hydrolysates were assayed for phenolic content and
antioxidant activity. Cell proliferation of Jurkat, THP-1 and
peripheral blood mononuclear cells (PBMC) was evaluated by
3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide
assay. Chemotaxis was evaluated by Transwell chamber methods.
Immunoadherence of THP-1 was performed on cultured human
umbilical vein endothelial cells (HUVEC) cells. Cytokine released
from PBMC was measured by ELISA assay kits. Lymphocytemediated
cytotoxicity was carried out on KKU-425 cells. Proteins
associated with immunomodulation were analyzed by Western
immunoblotting assay.
Results: Rice bran hydrolysates were rich in phenolic compounds,
such as ferulic acid, catechin, quercetin, and quercetin glycosides.
Rice bran hydrolysates suppressed phytohemagglutinin (PHA)-
stimulated proliferation of PBMC and Jurkat cells, chemotaxis
of Jurkat and THP-1 cells, and immunoadherence of THP-1 on
HUVEC cultured cells. The cellular mechanism of rice bran
hydrolysates involved the activation of AMPK as well as suppression
of mTOR, NF-κB and VCAM-1. Rice bran hydrolysates potentiated
PBMC on the PHA-stimulated release of IL-2, TNF-α, IL-4 cells,
and IFN-γ and enhanced PHA-induced non-MHC-restricted
cytotoxicity on KKU-425 cancer cells.
Conclusions: The immunomodulatory effect of phytochemicals
derived from rice bran hydrolysates suggests its therapeutic potential
for further investigation. |
Publication
Journal Publication
ไทย