Neolignan inhibitors of antigen-induced degranulation in RBL-2H3 cells from the needles of Pinus thunbergii.
Nyckelord
Abstrakt
The ethanolic extract of the needles of Pinus thunbergii was found to suppress antigen mediated degranulation of rat basophilic leukemia (RBL-2H3) cells. A new neolignan glycoside, named pinusthunbergiside A (1), as well as six known neolignan glycosides (2-7) were isolated from the ethanolic extract using bioassay-guided fractionation. Their structures were elucidated by a combination of 1D and 2D NMR, HRESI-MS, and circular dichroism (CD) data. Compounds 2-7 were found for the first time in this plant. The inhibitory effects of isolated constituents on the release of β-hexosaminidase from RBL-2H3 cells were examined, and compounds 2, 3, 5, and 6 were found to show the inhibitory activity with IC₅₀ values ranging between 52.3 and 75.3 μM.