Biochemical studies on the antiulcer effect of glucosamine on antioxidant defense status in experimentally induced peptic ulcer in rats

The present study examined the antiulcer effect of glucosamine on mucosal antioxidant defense system in ibuprofen-induced peptic ulcer in male albino rats. The number of lesions in the gastric mucosa, volume of gastric juice, acid output, pepsin activity, lipid peroxides, reduced glutathione content and the activities of glutathione dependent antioxidant enzymes (glutathione peroxidase and glutathione-S-transferase) and antiperoxidative enzymes (catalase and superoxide dismutase) were determined. Prior oral administration of glucosamine significantly prevented the ibuprofen-induced increases in the number of lesions in the gastric mucosa, volume of gastric juice and acidity. It also maintained the activity of pepsin at near normal level. Oral pretreatment of glucosamine exerted a significant antioxidant effect by preventing ibuprofen-induced lipid peroxidation and by maintaining the level of reduced glutathione and the activities of mucosal antioxidant enzymes at near normalcy. The results of the present investigation indicate that the antiulcer activity of glucosamine is related to its ability to neutralize the hydrochloric acid secreted into the stomach and to its antioxidant capability to inhibit ibuprofen-induced lipid peroxidation.