Short-term zinc supplementation attenuates Helicobacter felis-induced gastritis in the mouse

Background. Mucosal damage by H. pylori infection is mainly caused by neutrophils producing large quantities of reactive oxygen species (ROS). Metallothionein (MT) an intracellular, low-molecular, cysteine-rich protein, which is inducible by dietary zinc (Zn), has been implicated in sequestering ROS. This study examines the effects of Zn supplementation on Helicobacter colonisation and associated gastritis and the relationship with gastric MT levels. Methods. C57Bl/6 mice were inoculated with either 108 H. pylori or H. felis and were infected for 4 weeks or 6 and 12 weeks, respectively. Mice infected with H. pylori (4 weeks) or H. felis (6 weeks) were treated with either Zn acetate (ZnA; 1 mg/ml), or Zn sulphate (ZnSO4; 5 mg/ml) for 2 weeks with 0.1 ml oro-gastric gavage twice daily. H. pylori load and H. felis colonisation density were determined by culture and microscopy, respectively. MT levels and H. felis-induced gastritis were also determined. Results. Zn treatment showed no significant difference in Helicobacter load and gastric MT, however, ZnSO4 treatment showed a significant (p < 0.05) increased in gastric MT in H. felis infected mice. Both Zn-treated groups showed a significant (p < 0.05) difference in gastritis score in the antrum of the stomach within the basal and submucosal compartments compared to H. felis-infected controls. Conclusions. We found that H. felis-induced gastritis can be attenuated by short-term treatment of Zn. This observation suggests that Zn alone may be effective for the suppression of gastric mucosal inflammation induced by Helicobacter. (c) 2004 The British Infection Society. Published by Elsevier Ltd. All rights reserved.