IHEM   20887
INSTITUTO DE HISTOLOGIA Y EMBRIOLOGIA DE MENDOZA DR. MARIO H. BURGOS
Unidad Ejecutora - UE
congresos y reuniones científicas
Título:
Un nuevo xantanólido sesquiterpeno con propiedades antiulcerosas inhibe la degranulación de mastocitos inducida por el ionóforo de calcio A23187
Autor/es:
VERA ME; PRIVITERA M; MARIANI ML; FOGAL TH; FAVIER S; TONN C; PIEZZI RS; PENISSI AB
Lugar:
Mendoza
Reunión:
Jornada; IX Jornadas de Investigacion de la Facultad de Ciencias Médicas de la Universidad Nacional de Cuyo; 2007
Resumen:
In previous work we have demonstrated that xanthatin (Xt), a novel xanthanolide sesquiterpene with antiulcer properties isolated from Xanthium cavanillesii Schouw, inhibits mast cell exocytosis induced by the G protein stimulant compound 48/80. The present work examines the effect of Xt on mast cell degranulation induced by the calcium ionophore A23187, to determine whether Xt acts upstream or downstream of cytosolic calcium increase. Rat peritoneal mast cells were purified in Percoll and incubated with: 1) Tyrode solution or 2) A23187 or 3) Xt+A23187. Serotonin release studies by high performance liquid chromatography (HPLC), evaluation of mast cell morphology by light microscopy, dose-response and timeresponse studies, cell viability evaluation by the tripan blue dye exclusion, comparative studies with ketotifen (Ket), and drug stability evaluation by thin layer chromatography (TLC) were carried out. Calcium ionophore increased serotonin release from mast cells and elicited evident morphological changes. These effects were inhibited by Xt in a dose- and time-dependent manner. The inhibitory effect exhibited by Xt was stronger than that of ketotifen, a classical mast cell stabilizer. In conclusion, the present study demonstrates that Xt inhibits A23187-induced mast cell activation, acting downstream of cytosolic calcium increase.Schouw, inhibits mast cell exocytosis induced by the G protein stimulant compound 48/80. The present work examines the effect of Xt on mast cell degranulation induced by the calcium ionophore A23187, to determine whether Xt acts upstream or downstream of cytosolic calcium increase. Rat peritoneal mast cells were purified in Percoll and incubated with: 1) Tyrode solution or 2) A23187 or 3) Xt+A23187. Serotonin release studies by high performance liquid chromatography (HPLC), evaluation of mast cell morphology by light microscopy, dose-response and timeresponse studies, cell viability evaluation by the tripan blue dye exclusion, comparative studies with ketotifen (Ket), and drug stability evaluation by thin layer chromatography (TLC) were carried out. Calcium ionophore increased serotonin release from mast cells and elicited evident morphological changes. These effects were inhibited by Xt in a dose- and time-dependent manner. The inhibitory effect exhibited by Xt was stronger than that of ketotifen, a classical mast cell stabilizer. In conclusion, the present study demonstrates that Xt inhibits A23187-induced mast cell activation, acting downstream of cytosolic calcium increase.