prostaglandin-d2 and Gastritis

Immunological responses in the host can result in different disease outcomes of Helicobacter pylori-induced gastritis. Prostaglandin E2 derived from cyclooxygenase (COX) and prostaglandin E synthase contribute to gastric protection. Recently, prostaglandin D2 was shown to be involved in host immunity by chemotactic activity through chemoattractant receptor-homologous molecule expressed on Th2 cells (CRTH2), but its role in H. pylori-induced gastritis has not been clarified. We determined the expression levels of mRNAs for haematopoietic PGD synthase (H-PGDS) and lipocalin-type PGDS (L-PGDS), MIP-1 alpha, IFN-gamma, IL-4, and CDX2 in H. pylori-induced gastritis mucosa by quantitative RT-PCR. We found that L-PGDS was constitutively expressed in the epithelium of the glandular base. L-PGDS, but not H-PGDS, was induced on fibroblasts close to infiltrating cells in the H. pylori-infected gastric mucosa. These fibroblasts co-expressed COX-2. The level of L-PGDS mRNA expression decreased as gastritis became more severe. In most of the H. pylori-infected gastric mucosa, CCR5(+) cells had more actively infiltrated than had CRTH2(+) cells. However, the expression level of IFN-gamma was lower in the mucosa of the CRTH2(+) cells-dominantly infiltrating group than that of the less CRTH2-infiltrating group. Exogenously added PGD2 decreased the H. pylori-induced expression of IFN-gamma in peripheral blood mononuclear cells in vitro. The data suggest that PGD2 derived from the gastric mucosa and fibroblasts plays protective roles against inflammatory changes in H. pylori-induced gastritis.

Topics: Adult; Aged; Aged, 80 and over; CDX2 Transcription Factor; Cells, Cultured; Chemokine CCL3; Cyclooxygenase 1; Cyclooxygenase 2; Cytokines; Female; Gastric Mucosa; Gastritis; Gene Expression Regulation; Helicobacter Infections; Homeodomain Proteins; Humans; Interferon-gamma; Intramolecular Oxidoreductases; Lipocalins; Male; Middle Aged; Prostaglandin D2; Receptors, CCR5; Receptors, Immunologic; Receptors, Prostaglandin; Reverse Transcriptase Polymerase Chain Reaction; Young Adult