Inhibitory Effects of Ulmus parvifolia and Liriope platyphylla Wang et Tang on Histamine Release from Rat Peritoneal Mast Cells

Twenty-four different natural food materials extracted with 80% methanol were used to investigate the inhibition of cell-mediated immediate type allergic reactions induced by compound 48/80 in rat peritoneal mast cells (RPMCs). Nine 80% methanol extracts screened at a concentration of $10\;{\mu}g/mL$ inhibited histamine release from RPMCs induced by compound 48/80. Of these, two materials (Ulmus parvifolia and Liriope platyphylla Wang et Tang) were extracted and fractionated into four different solvent types (chloroform, ethylacetate, butanol, and water), and the fractions with major anti-allergic effects were assessed. The chloroform fraction of U. parvifolia (UP) at $5\;{\mu}g/mL$ and the ethylacetate fraction of L. platyphylla Wang et Tang (LPWT) at $1\;{\mu}g/mL$ showed the greatest inhibition of histamine release induced by compound 48/80. The chloroform fraction of UP and the ethylacetate fraction of LPWT in combination showed a greater inhibition of histamine release than either fraction alone. The cAMP levels in RPMCs treated with UP and LPWT were significantly greater than in cells treated with compound 48/80 alone. Our studies suggest that extracts from UP and LPWT may alleviate immediate type hypersensitivity reactions through the increase of cAMP levels in the mast cells.