Oxidative damage of the gastric mucosa in Helicobacter pylori positive chronic atrophic and nonatrophic gastritis, before and after eradication.
BACKGROUND
Helicobacter pylori is the main cause of gastritis and a primary carcinogen. The aim of this study was to assess oxidative damage in mucosal compartments of gastric mucosa in H. pylori positive and negative atrophic and nonatrophic gastritis.


METHODS
Five groups of 10 patients each were identified according to H. pylori positive or negative chronic atrophic (Hp-CAG and CAG, respectively) and nonatrophic gastritis (Hp-CG and CG, respectively), and H. pylori negative normal mucosa (controls). Oxidative damage was evaluated by nitrotyrosine immunohistochemistry in the whole mucosa and in each compartment at baseline and at 2 and 12 months after eradication. Types of intestinal metaplasia were classified by histochemistry.


RESULTS
Total nitrotyrosine levels appeared significantly higher in H. pylori positive than in negative patients, and in Hp-CAG than in Hp-CG (p <.001); no differences were found between H. pylori negative gastritis and normal mucosa. Nitrotyrosine were found in foveolae and intestinal metaplasia only in Hp-CAG. At 12 months after H. pylori eradication, total nitrotyrosine levels showed a trend toward a decrease in Hp-CG and decreased significantly in Hp-CAG (p =.002), disappearing from the foveolae (p =.002), but remaining unchanged in intestinal metaplasia. Type I and II of intestinal metaplasia were present with the same prevalence in Hp-CAG and CAG, and did not change after H. pylori eradication.


CONCLUSIONS
Oxidative damage of the gastric mucosa increases from Hp-CG to Hp-CAG, involving the foveolae and intestinal metaplasia. H. pylori eradication induces a complete healing of foveolae but not of intestinal metaplasia, reducing the overall oxidative damage in the mucosa.
Iacopini
Federico
F
Gastroenterology Unit, Department of Clinical Sciences, University La Sapienza of Rome, Italy.
Consolazio
Adriana
A
Bosco
Daniela
D
Marcheggiano
Adriana
A
Bella
Antonino
A
Pica
Roberta
R
Paoluzi
Omero A
OA
Crispino
Pietro
P
Rivera
Margherita
M
Mottolese
Marcella
M
Nardi
Francesco
F
Paoluzi
Paolo
P
D000328:Adult; D000368:Aged; D002908:Chronic Disease; D005260:Female; D005753:Gastric Mucosa / Q000737:chemistry / Q000382:microbiology / Q000473:pathology*; D005756:Gastritis / Q000378:metabolism / Q000382:microbiology* / Q000473:pathology*; D005757:Gastritis, Atrophic / Q000378:metabolism / Q000382:microbiology / Q000473:pathology; D016481:Helicobacter Infections / Q000378:metabolism / Q000382:microbiology / Q000473:pathology*; D016480:Helicobacter pylori / Q000302:isolation & purification*; D006801:Humans; D007150:Immunohistochemistry; D008297:Male; D008679:Metaplasia; D008875:Middle Aged; D014443:Tyrosine / Q000031:analogs & derivatives* / Q000032:analysis / Q000276:immunology
C002744:3-nitrotyrosine; D014443:Tyrosine