Paeoniflorin suppress NF-κB activation through modulation of IκBα and enhances 5-fluorouracil-induced apoptosis in human gastric carcinoma cells

Objective: We sought to determine whether paeoniflorin enhances 5-fluorouracil-induced apoptosis in human gastric carcinoma cells, and, if so, to determine the relationship between this apoptosis and NF-kappa B activation. Methods: Paeoniflorin was diluted to different concentrations and added to gastric carcinoma cells (SGC-7901) at different times. Western blot was used to test the expression of NF-kappa B in nuclear and I kappa B alpha, p-I kappa B alpha, IKK alpha in cytoplasm. Further, the intranuclear expression of NF-kappa B was confirmed by ELISA assay. The impact of paeoniflorin and 5-fluorouracil on cell apoptosis of gastric carcinoma cells was estimated by flow cytometry. Results: Paeoniflorin revealed dramatic inhibition of NF-kappa B activity in the nuclei of the cells. The inhibition pattern of NF-kappa B was exhibited in a time- and dose-dependent manner, which was confirmed by Western blot and ELISA. Decreased nuclear translocation of IF-kappa B induced by paeoniflorin was found by preventing I kappa B alpha phosphorylation. Moreover. 5-fluorouracil-induced cell apoptosis was promoted by paeoniflorin in gastric carcinoma cells. Conclusions: Paeoniflorin can inhibit NF-kappa B activity of SGC-7901 cells. and enhance 5-fluorouracil-induced apoptosis of gastric carcinoma cells. (C) 2008 Elsevier Masson SAS. All rights reserved.