Anti-inflammatory effects of caffeic acid phenethyl ester (CAPE), a nuclear factor-kappaB inhibitor, on Helicobacter pylori-induced gastritis in Mongolian gerbils

Abstract

Nuclear factor-kappaB (NF-kappaB) plays a major role in host inflammatory responses and carcinogenesis and as such is an important drug target for adjuvant therapy. In this study, we examined the effect of caffeic acid phenethyl ester (CAPE), an NF-kappaB inhibitor, on Helicobacter pylori (H. pylori)-induced NF-kappaB activation in cell culture and chronic gastritis in Mongolian gerbils. In AGS gastric cancer cells, CAPE significantly inhibited H. pylori-stimulated NF-kappaB activation and mRNA expression of several inflammatory factors in a dose-dependent manner, and prevented degradation of IkappaB-alpha and phosphorylation of p65 subunit. To evaluate the effects of CAPE on H. pylori-induced gastritis, specific pathogen-free male, 6-week-old Mongolian gerbils were intragastrically inoculated with H. pylori, fed diets containing CAPE (0-0.1%) and sacrificed after 12 weeks. Infiltration of neutrophils and mononuclear cells and expression of NF-kappaB p50 subunit and phospho-IkappaB-alpha were significantly suppressed by 0.1% CAPE treatment in the antrum of H. pylori-infected gerbils. Labeling indices for 5'-bromo-2'-deoxyuridine both in the antrum and corpus and lengths of isolated pyloric glands were also markedly reduced at the highest dose, suggesting a preventive effect of CAPE on epithelial proliferation. Furthermore, in the pyloric mucosa, mRNA expression of inflammatory mediators including tumor necrosis factor-alpha, interferon-gamma, interleukin (IL)-2, IL-6, KC (IL-8 homologue), and inducible nitric oxide synthase was significantly reduced. These results suggest that CAPE has inhibitory effects on H. pylori-induced gastritis in Mongolian gerbils through the suppression of NF-kappaB activation, and may thus have potential for prevention and therapy of H. pylori-associated gastric disorders.