Endocrine Abstracts

Aim: The work was initiated to study TNF-α gene polymorphism and parameters of oxidative stress in patients with type 2 diabetes mellitus

Materials and methods: We examined 41 healthy subjects and 20 patients with diabetes mellitus to study G308A (rs1800629) polymorphism in TNF-α gene by means of allele-specific PCR method (AS-PCR). Rates of lipid peroxidation (LP) were determined by concentration of malon dialdehyde (MDA); catalase activity was assessed by antioxidant protection degree.

Results: Excessive production of TNF-α is known as a pathological link in diabetes mellitus onset and progression. In our study, frequency of GG, GA and DD in patients with diabetes mellitus was 85.0, 15 and 0.0, respectively. Frequency of GG, GA and AA genotypes in the control group was 90.2, 9.8 and 0.0%, respectively. Frequency of A-allele, the one associated with the increased production of TNF-α, in the diabetics and healthy volunteers was 7.5 and 4.9%, respectively. Our findings demonstrated significant LP intensification with accumulation of secondary products in the blood serum of all patients with diabetes mellitus (MDA concentrations increased by 2.5 times), and suppression of activity of catalase more than by two times in the diabetics as compared with the controls.

Conclusions: In patients with diabetes mellitus frequency of a mutant A-allele in TNF-α gene is higher than in healthy persons. Our findings indicate significant role of G308A polymorphism in TNF-α gene in pathogenesis of diabetes mellitus. In patients with type 2 diabetes mellitus we have managed to establish correlation between intensity of oxidative stress and TNF-α production.