The aim of this study is to investigate the effects of VYAC on degranulation and to determine its anti-inflammatory mechanism in RBL-2H3 mast cells.
VYAC was extracted with water-coction extraction (Shufen et al., 2012). The aqueous extracts were concentrated in vacuum under reduced pressure and lyophilized using a freeze dryer, and lyophilized powder was obtained. MTT was used to evaluate the cytotoxic of VYAC on RBL-2H3 cells. Degranulation was carried out with RBL-2H3 cell model, which was stimulated with A23187 plus PMA. β-Hexosaminidase and histamine were measured to evaluate degranulation. The mRNA levels of inflammation cytokines (IL-1β, TNF-α, IL-6, and iNOS) were investigated by RT-PCR to explain the anti-inflammatory mechanism of VYAC.
VYAC did not show cytotoxic effect on RBL-2H3 cells in the range of 25–400 μg/mL. A higher dose of VYAC (800 μg/mL) showed significant cytotoxicity (P<0.05). VYAC could significantly inhibit β-hexosaminidase and histamine release when treated with 100, 200, and 400 μg/mL (P<0.05), but could not significantly inhibit β-Hexosaminidase and histamine release when treated with 25 and 50 μg/mL (p>0.05). The mRNA levels of inflammatory cytokines (TNF-α, IL-1β, IL-6, and iNOS) could significantly decrease when treated with 200 and 400 μg/mL (P<0.05) of VYAC, which were associated with the development of inflammation.
Results showed that VYAC inhibited β-hexosaminidase and histamine release, which was inhibit A23187 plus PMA stimulated RBL-2H3 cell degranulation and downregulated inflammatory cytokines (IL-1β, TNF-α, IL-6, and iNOS) expression to block inflammatory development.