Evidence for protective and antioxidant properties of rutin, a natural flavone, against ethanol induced gastric lesions

This study was designed to determine the ulcer-protecting effects of rutin, a natural flavone, against gastric lesions induced by 50% ethanol, the exp erimental model related to lesion pathogenesis with production of reactive species. The possible involvement of sulphydryl compounds (SH), neutrophil infiltration, and the capacity of this flavone to restrain the oxidative pr ocess produced in the gastric tissue were also investigated. The levels of thiobarbituric acid (TBA, as index of lipid peroxidation), the myeloperoxid ase activity (MPO, as a marker of neutrophil infiltration), the content of mucosal sulphydryls (SH) groups and the activity of glutathione peroxidase (GSH-Px, an important antioxidant enzyme) were determined. Pretreatment wit h the highest dose of rutin (200 mg/kg), 120 min before 50% ethanol, result ed in the most effective necrosis prevention. TEA reactive substances in th e gastric mucosal were increased by ethanol injury, and this increase was i nhibited by the administration of 200 mg:kg of rutin. However, the flavonoi d was not able to modify the ethanol-induced neutrophil infiltrate expresse d as myeloperoxidase activity. Exposure of the gastric mucosa to 50% ethano l induced a significant diminution in gastric non-protein SH content; this parameter also was not modified by the treatment with rutin. GSH-Px activit y decreased in the gastric mucosa after ethanol-treatment, In contrast, rut in at all tested doses induced a significant increase in this enzymatic act ivity, higher than in control group. These results suggest that the gastrop rotective effect of rutin in this experimental model appears through an ant i-lipoperoxidant effect, and also by enhancement of the anti-oxidant enzyma tic (GSH-Px) activity. (C) 2000 Published by Elsevier Science Ireland Ltd. All rights reserved.