Influences of Helicobacter pylori on cyclooxygenase-2 expression and prostaglandinE2 synthesis in rat gastric epithelial cells in vitro

J Gastroenterol Hepatol. 2006 Apr;21(4):754-8. doi: 10.1111/j.1440-1746.2006.04299.x.


Background and aim: It is known that cyclooxygenase (COX)-2 is over expressed in gastrointestinal neoplasia and Helicobacter pylori (H. pylori) infection is causally linked to gastric cancer. The present study aimed to elucidate the effects of H. pylori on COX-2 expression and prostaglandinE(2) (PGE(2)) production in a gastric epithelial cell line derived from normal rat gastric mucosa (RGM1).

Method: H. pylori water extracts were prepared from a supernatant of the H. pylori suspension in distilled water. RGM1 cells were cultured with H. pylori water extracts at the final concentration of 2.5, 5, 10 microg/mL for 24 h. For the time sequence study, RGM1 cells were cultured with 10 microg/mL H. pylori water extracts for 0, 6, 12, 24 and 48 h. COX-1 and COX-2 expression in the RGM1 cells was analyzed by western blotting. The levels of PGE(2) in the cultured media were measured by enzyme immunoassay.

Results: H. pylori did not affect COX-1 expression; whereas COX-2 expression increased by six-fold at 24 h after incubation of RGM1 cells with 10 microg/mL H. pylori water extracts. The increase in COX-2 expression was evident after 12 h of incubation; reached a peak at 24 h and declined at 48 h. H. pylori dose dependently increased COX-2 expression and PGE(2) synthesis in RGM1 cells.

Conclusion: H. pylori induces COX-2 expression and increases PGE(2) synthesis in RGM1 cells in vitro. These results indicate that H. pylori-associated gastric carcinogenesis may depend on COX-2 expression.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Animals
  • Cells, Cultured
  • Cyclooxygenase 2 / metabolism*
  • Dinoprostone / metabolism*
  • Epithelial Cells / metabolism*
  • Epithelial Cells / microbiology*
  • Gastric Mucosa / metabolism*
  • Gastric Mucosa / microbiology*
  • Gene Expression / physiology
  • Helicobacter pylori / physiology*
  • Rats
  • Rats, Wistar


  • Cyclooxygenase 2
  • Ptgs2 protein, rat
  • Dinoprostone