Biochemical and morphological changes in human mast cells exposed to natural alpha,beta-unsaturated lactones

VERA M.E.; MARIANI M. L.; ROJAS RUDOLPH, G.; YEFI, R.; DE ROSAS J.C.; FOGAL T. H.; TONN, C.E.; PIEZZI, R. S.; PENISSI A. B.

Ciudad de la Punta, San Luis, Argentina

Congreso; XXVII Reunion Cientifica Anual de la Sociedad de Biologia de Cuyo - 2009; 2009

Sociedad de Biologia de Cuyo

The present work was designed to examine the effect of a sesquiterpene lactone isolated from Artemisia douglasiana Besser (dehydroleucodine, DhL) and a xanthanolide isolated from Xanthium cavanillesii Schouw (xanthatin, Xt) on compound 48/80- and calcium ionophore A23187-induced human mast cell degranulation, with the goal of testing the hypothesis that such molecules act as mast cell stabilizers. The human LAD-2 cell line was incubated with: 1) Buffer (control) or 2) 48/80 or 3) A23187 or 4) DhL+48/80 or 5) DhL+ A23187 or 6) Xt+48/80 or 7) Xt+A23187. â-hexosaminidase release studies by colorimetric reaction, evaluation of mast cell morphology by light (toluidine blue staining) and electron (transmission and scanning) microscopy, dose-response and time-response curves, and comparative studies with sodium cromoglicate (Crgl) were carried out. Compound 48/80 and A23187 increased â-hexosaminidase release from LAD-2 cells and elicited evident granule ultrastructural changes. These effects were inhibited by DhL and Xt in a dose- and time- dependent manner. The present study demonstrates that DhL and Xt inhibit compound 48/80-and A23187-induced mast cell activation, acting thus as mast cell stabilizers in a human mast cell line.