Oxidative DNA damage and oxidized low density lipoprotein in Type II diabetes mellitus among patients with Helicobacter pylori infection

BACKGROUND Helicobacter pylori (H. pylori) infection is reported to be associated with various extragastrointestinal conditions such as insulin resistance, diabetes mellitus and metabolic syndrome. H. pylori infection and type 2 diabetes mellitus (T2DM) are associated with oxidative stress, this cross-relation between H. pylori induced infection in T2DM and oxidative damage is still debated. Thus, the question arises whether an increase in the serum level of 8-OHdG and Ox-LDL will occurs in patients with T2DM infected H. pylori; this will be through determination and compare frequency of H. pylori infection in T2DM and non-diabetic patients. METHODS 100 patients presented with history of epigastric discomfort for more than 1 month; 50 patients with T2DM and 50 non-diabetics. Anti-H. pylori IgG using ELISA, fasting and postprandial glucose level, glycated hemoglobin (HbA1c) and body mass index (BMI) was calculated. Serum 8-OHdG and Ox-LDL was measured using ELISA for the 100 patients and 50 control subject. RESULTS Rates of H. pylori infection of T2DM and non-diabetic were 66 and 58 %, respectively, (p = 0.001). H. pylori IgG antibody was not correlated with HbA1c either in T2DM (p = 0.06) or non-diabetic (p = 0.25). Serum 8-OHdG level in T2DM with positive H. pylori infection showed a significant difference compared to non-diabetics with positive H. pylori infection (p = 0.001) and higher than that in T2DM with negative H. pylori. A correlation between 8-OHdG concentration and HbA1c in T2DM patients infected with H. pylori was observed (r = 0.39, p = 0.02). Serum Ox-LDL level in T2DM with positive H. pylori infection showed a significant difference compared to diabetics with both negative H. pylori infection and in non-diabetics with positive H. pylori infection (p = 0.001). CONCLUSIONS Increased levels of oxidative DNA damage (8-OHdG) and Ox-LDL suggest the mechanistic link between H. pylori infection combined with diabetes and increased generation of ROS and could play as an important image for high risk to atherosclerosis.