THE RELATION BETWEEN GASTRIC VITAMIN-C CONCENTRATIONS, MUCOSAL HISTOLOGY, AND CAGA SEROPOSITIVITY IN THE HUMAN STOMACH

Background - Vitamin C may be protective against gastric cancer though infection with Helicobacter pylori is associated with a reduction in intragastric concentrations of vitamin C. Aims - To examine the effect s of H pylori infection, gastric juice pH, the severity and extent of gastric inflammation, and CagA antibody status of the individual on ga stric juice and mucosal vitamin C concentrations. Patients - One hundr ed and fifteen patients undergoing routine gastroscopy for investigati on of dyspepsia. Methods - High performance liquid chromatography was used to determine vitamin C concentrations. CagA antibody was detected by western blot analysis. Results - Gastric juice ascorbic acid conce ntration was significantly lower in patients infected with H pylori co mpared with those uninfected (19.3 mu mol/l (interquartile range (IQR) 10.7-44.5) versus 66.9 mu mol/l (IQR 24.4-94.2), p = 0.003). The redu ction in gastric juice ascorbic acid concentration was inversely relat ed to the severity of gastritis (p = 0.01). CagA positive patients had significantly lower gastric juice ascorbic acid concentrations than C agA negative ones (14.8 mu mol/l (IQR 7.9-52.2) versus 39 mu mol/l (IQ R 19.9-142.2), p = 0.05). Decreased gastric juice dehydroascorbic acid concentrations were observed in patients with gastric atrophy and int estinal metaplasia. mucosal ascorbic acid concentrations were also sig nificantly lower in infected patients than uninfected patients (p = 0. 04). Conclusions - The reduction in gastric vitamin C concentrations i s related to gastric juice pH, the severity and extent of gastritis, t he presence of H pylori, and the CagA antibody status of the individua l. These findings may have implications in H pylori associated carcino genesis.