Capsaicin protects against ethanol-induced oxidative injury in the gastric mucosa of rats.

In this study, we investigated the protective effects of capsaicin on gastric mucosal oxidative damage induced by ethanol. Sprague Dawley rats intragastrically received 0.5-10 mg/kg, BW capsaicin or vehicle; 30 min later gastric lesions were induced by intragastric administration of absolute ethanol. Lipid peroxidation was estimated by measuring thiobarbituric acid reactive substances in gastric mucosa. Myeloperoxidase activity, a marker enzyme of polymorphonuclear leukocytes for tissue inflammation, was also measured in the gastric mucosa. The expression level of cyclooxygenase-2, which increases in inflammatory region, was determined by Western blot analysis. Capsaicin significantly suppressed gastric haemorrhagic erosions induced by ethanol. Capsaicin inhibited lipid peroxidation and myeloperoxidase activity in ethanol-induced gastric mucosal lesion in a dose-dependent manner. Capsaicin also inhibited the expression of cyclooxygenase-2 in the gastric mucosal lesion. The gastroprotective activity of capsaicin on the ethanol-induced oxidative damage may be important for chemoprevention.