Curcumin suppresses gastric NF-κB activation and macromolecular leakage in Helicobacter pylori-infected rats

Abstract

AIM: To investigate whether curcumin could attenuate nuclear factor (NF)-κB p65 expression and macromolecular leakage in the gastric mucosa of Helicobacter pylori (H. pylori)-infected rats. METHODS: Twenty-five male Sprague-Dawley rats were equally divided into five groups: control rats (Control), control rats supplemented with 600 mg/kg curcumin, H. pylori -infected rats (Hp), H. pylori -infected rats supplemented with 200 mg/kg curcumin (Hp + cur 1), and H. pylori -infected rats supplemented with 600 mg/kg curcumin (Hp + cur 1). In H. pylori -infected groups, rats were inoculated with H. pylori suspension twice a day at an interval of 4 h for 3 d. Two weeks later, 200 or 600 mg/kg curcumin was given once daily to curcuminsupplemented groups for 7 d. On the day of the experiment, macromolecular leakage in gastric mucosa was examined by intravital fluorescence microscopy. The stomach tissue was removed to examine NF-κB p65 expression in gastric epithelial cells by immunohistochemistry. RESULTS: The expression of NF-κB p65 in gastric epithelial cells and the macromolecular leakage from gastric mucosal microcirculation significantly increased in the Hp group compared with the Control group. The percentages of NF-κB p65 immunoreactive cells in Control and Hp groups were 10.72% ± 2.10% vs 16.02% ± 2.98%, P = 0.004, respectively. The percentages of macromolecular leakage in Control and Hp groups were 10.69% ± 1.43% vs 15.41% ± 2.83%, P = 0.001, respectively. Curcumin supplementation in Hp + curI and Hp + curII groups significantly decreased NF-κB p65 immunoreactive cells and macromolecular leakage compared with results in the Hp group. The percentages of NF-κB p65 immunoreactive cells in Hp + cur1 and Hp + curII groups were 11.79% ± 2.13% (P = 0.017) and 11.42% ± 1.68% (P = 0.010), respectively. The percentages of macromolecular leakage in Hp + curI and Hp + curII groups were 12.32% ± 2.13% (P = 0.025) and 12.14% ± 1.86% (P = 0.018), respectively. CONCLUSION: H. pylori -induced gastric inflammation in rats is associated with increased NF-κB activation and macromolecular leakage which can be reduced by curcumin supplementation. © 2010 Baishideng.