Effect of common food additives on mast cell activation

Mast cells play a central role in the genesis and modulation of allergic and inflammatory responses. The general aim of the present work was to study the interaction between mast cells and the most common additives approved for use in foods. Dose-response studies about the effect of the main food additives (tartrazine, sodium bisulphite and sodium benzoate) on mast cell degranulation were carried out. Rat peritoneal mast cells were incubated with: 1) buffer solution or 2) stimulus. The stimuli were tartrazine, sodium benzoate, sodium bisulphite and the calcium ionophore A23187. A23187 was used as a reference mast cell secretagogue. Different doses and combinations of food additives were used. The viability of the mast cells was evaluated with trypan blue. In the incubation solutions, the release of β-hexosaminidase was quantified by colorimetric reaction and ELISA plate reader. The remaining β-hexosaminidase concentration (not released) was studied in the cells after the incubations, and morphology of the mast cells was analyzed by light microscopy with toluidine blue stain. The food additives tartrazine, sodium benzoate and sodium bisulphite did not stimulate the release of β-hexosaminidase from mast cells at any of the concentrations used. In contrast, tartrazine at concentrations of 0.1 μM and 1 μM, and sodium benzoate and sodium bisulphite at concentrations of 0.1 μM, 1 μM, 10 μM and 100 μM, significantly inhibited the basal release of β-hexosaminidase from mast cells. Considering these findings, we decided to determine the effect of these additives on the degranulation of mast cells induced by the calcium ionophore A23187. Sodium bisulphite inhibited mast cell activation induced by the calcium ionophore A23187 in this experimental model. The present study demonstrates that food additives of usual permitted use do not stimulate basal degranulation of mast cells in an in vitro model of peritoneal mast cells and that the additive sodium bisulphite inhibit mast cell activation induced by intracellular calcium increase. This food additive could represent an interesting alternative in the prevention of pathologies mediated by mast cells, as well as in the field of nutritional biochemistry