Effect of sofalcone on adherence, production of vacuolating toxin, and induction of interleukin-8 secretion by Helicobacter pylori

We examined the effect of sofalcone, a mucosal protective agent that has been reported to inhibit growth of Helicobacter pylori, on adherence, production of vacuolating toxin (VT), and induction of interleukin-8 (IL-8) secretion by H. pylori. Mixing VT with various concentrations (1.5-100 mu g/ml) of sofalcone resulted in a 50% decrease in the VT titer. When toxigenic H. pylori strains were incubated in the presence of sofalcone (20 and 40 mu g/ml). although bacterial growth was not inhibited significantly there was significant inhibition of VT production. Notable inhibition of IL-8 secretion by human gastric cancer cells (MKN 45) was detected in the presence of sofalcone (20-100 mu g/ml) after co-incubation with H. pylori strains. In flow cytometric analysis, adherence of H. pylori strains to MKN 45 cells was significantly inhibited by treatment with sofalcone (20-60 mu g/ml), indicating at least one reason for the inhibition of IL-8 secretion. These results show that sofalcone is an effective mucosal protective agent that inhibits both production of VT and induction of IL-8 secretion.