GASTRIC ANTIOXIDANT, NITRITES, AND MUCOSAL LIPOPEROXIDATION IN CHRONIC GASTRITIS AND HELICOBACTER-PYLORI INFECTION

We have evaluated gastric juice pH, nitrites and vitamin C levels, muc osal glutathione, and malondialdehyde, a marker of lipid peroxidation, in patients with chronic gastritis undergoing endoscopy. Patients had chronic gastritis with (n = 28) or without (n = 60) atrophy and/or co ncomitant Helicobacter pylori infection. Nineteen healthy subjects, wi thout major macroscopic or histologic changes, were included as contro ls. Ten subjects were studied before and after H. pylori eradication. Vitamin C levels were low in atrophic gastritis (p < 0.006) and H. pyl ori infection (p < 0.02). Nitrite concentrations and pH were significa ntly higher in atrophy (p < 0.005 and 0.0001). Glutathione turnover wa s higher than normal in gastritis, with higher levels of oxidized glut athione (p < 0.02). Gastric malondialdehyde levels were significantly increased by gastritis (p < 0.05) and H. pylori infection (p < 0.05). Overall, more active gastritis coincided with lower vitamin C levels a nd higher malondialdehyde levels. After H. pylori eradication a drop i n mucosal MDA levels was observed (p = 0.04). In summary, chronic gast ritis and H. pylori infection correlate with increased free-radical pr oduction, reduced gastric vitamin C levels, and increased glutathione turnover. The possible implications of these changes in the pathogenes is of gastric damage and in carcinogenesis are intriguing.