Influence of COX-2 and local cytokine expressions in gastric ulcer mucosa by H. pylori and NSAID

H. pylori and NSAIDs are the two most important pathogenic factors in gastric ulcer. NSAIDs and H. pylori share common pathogenic characteristics, but have different effects in modulating COX-2 and local cytokines in gastric ulcer mucosa. This study was designed to explore the influence of COX-2 and local cytokine expressions in gastric ulcer mucosa induced by H. pylori infection and NSAID use.

Twenty-three patients were recruited. Sixteen subjects were infected with H. pylori. Fifteen patients used NSAIDs. Gastric biopsy specimens were obtained by endoscopy. COX-2 and local cytokine mRNA expressions were assessed by real-time RT-PCR.

COX-2 and local cytokines were over-expressed in gastric ulcer and were positively intercorrelated. H. pylori did not alter COX-2 and local cytokine expressions in gastric ulcer, but induced IL-8 and COX-2 in antral mucosa. NSAIDs inhibited COX-2 expression in gastric ulcer, but had no effect on other local cytokines. COX-2 inhibition by NSAIDs in gastric ulcer was compatible with the findings that NSAIDs delayed gastric ulcer healing.

H. pylori increased IL-8 and COX-2 in the antral mucosa, but did not influence COX-2 and local cytokines in gastric ulcer. NSAIDs inhibited COX-2 in gastric ulcer and delayed gastric ulcer healing.