MEASUREMENT OFMALONDIALDEHYDE AND THIOL LEVEL IN IRAQI PATIENTS WITH GASTRO DUODENAL DISEASES

It has been suggested that the free radicals are closely related with peptic ulcer disease and gastritis. Although many studies have been undertaken to clarify the role of oxygen-derived free radicals, most of them were carried out animal models. The aims of this study were to assess the reactive oxygen species activity and the damage in Helicobacter pylori infected gastric mucosa in humans. In a total 50 patients there were 35 cases of peptic ulcer, 15 cases of gastritis and 12 control subjects. Measurement of plasma malondialdehyde concentrations, which is the end-product of lipid peroxidation, was used to assess oxidative damage to membranes in patients with peptic ulcer and gastritis. Plasma glutathione concentrations were also measured in order to study whether reactive oxygen species generation affects levels of the antioxidant peptide. Results showed that plasma levels of glutathione were significantly reduced (p 0.001) and malondialdehyde was higher (p 0.001) in patients with peptic ulcer compared to controls. In patients with gastritis, glutathione was also lower (p 0.001) and malondialdehyde higher (p 0.01). The study concluded that depletion of plasma glutathione in cases with H. pylori positive peptic ulcer and gastritis may be caused by accumulation of free radicals that can initiate membrane damage by lipid peroxidation that increased plasma malondialdehyde concentration.