Effect of mycotoxins on some activities of isolated human neutrophils.

Activities of mycotoxins--citrinin, ochratoxin B, rubratoxin B, and zearalenol beta--that affected superoxide anion (O2-) production were studied on human neutrophils with regard to hypochlorous acid (HOCl) generation, nitric oxide (NO) formation, and chemotaxis of isolated cells. At the doses of 10(-8), 10(-6), 10(-4), or 10(-2) mg/mL, in stimulated cells the mycotoxins inhibited HOCl production proportionally to that of O2- because HOCl production is directly dependent on O2- generation. But unlike the others, zearalenol beta decreased HOCl production much more than one of O2-, indicating an effect also on myeloperoxidase secretion. All mycotoxins inhibited NO generation but only at the dose of 10(-2) mg/mL. Formyl-met-leu-phe-induced chemotaxis of neutrophils was deeply affected as well, as all mycotoxins at all doses used decreased it. All considered effects were not dose-dependent, likely connected to high variability of individual sensitivity to these compounds and because they already are present in blood introduced with foods. These activities of neutrophils confirm and extend the danger for immune systems by mycotoxins also in very small quantities, since the smaller concentrations we used are easily reachable in blood.

Anti-inflammatory effect of lemon mucilage: in vivo and in vitro studies.

The mucilage extracted from a lemon juice centrifugation pulp was studied for its anti-inflammatory effect in rat. In vivo the lemon mucilage significantly inhibited carrageenan-induced edema in rat paw from 59% to 73.5% showing the highest effect at the third hour. In vitro, at the doses of 10(-8), 10(-6), 10(-4) or 10(-2) mg/mL the lemon mucilage stimulated the superoxide anion production in rat testing neutrophils in whole blood but inhibited it in FMLP stimulated cells at the dose of 10(-2) mg/mL. The neutrophils of rats receiving p.o. the lemon mucilage for 21 days showed a significant decrease of 45.5% in O2- generation after FMLP stimulation, and a not-significant increase after phorbol-12-myristate-13-acetate (PMA) or zymosan stimulation. Since the activity on zymosan- and PMA-induced O2- production was not significant, the inhibition exerted by FMLP in rat neutrophils occurred mainly through the blockade of phospholipase D.

Effect of some mycotoxins on superoxide anion production of isolated human neutrophils and in whole blood.

Activity of mycotoxins citrinin, ochratoxin B, rubratoxin B, and zearalenol beta was studied on human neutrophils with regard to O2- generation. At the doses of 10(-8), 10(-6), 10(-4), or 10(-2) mg/mL the mycotoxins stimulated the superoxide anion production in resting neutrophils in whole blood but inhibited it in isolated cells. In neutrophils stimulated with zymosan or PMA, mycotoxins showed inibiting effect both on isolated and in whole blood cells. The behavior of resting isolated neutrophils, identical to that of stimulated cells, was caused by manipulations to isolate cells that activated O2- production. Activity of mycotoxins was no dose-dependent permitting to consider their effect immunotoxic rather than immunomodulator; the absence of dose-dependence was connected to high variability of individual sensitivity to these compounds. Since the smaller concentrations by us used (10(-8) and 10(-6) mg/mL) are easily reachable in blood, it is important to point out the danger represented for immune system by mycotoxins also in very small quantities.

Immunomodulatory effect of glutoxim on some activities of isolated human neutrophils and in whole blood.

Activity of Glutoxim, a sulfur-containing hexapeptide with immunomodulating effect on lymphocytes, was studied on human neutrophils. Commercial available agent containing the substance, Glutoxim, was used. At the doses of 1, 3, 6 or 100 microg/mL the drug stimulated the superoxide anion and hypochlorous acid generation in resting neutrophils but inhibited them in cells stimulated with zymosan or PMA. The only inhibiting effect was observed on nitric oxide production in LPS-stimulated RAW 264.7 cells. The drug also influenced neutrophil chemotaxis showing chemoattractant activity on cells and inhibiting fMLP-induced chemotaxis. These effects on neutrophils confirm and extend range of Glutoxim immunomodulating abilities.