Association Between the Polymorphism of Glu298Asp in Exon 7 of the eNOS Gene With Foot Ulcer and Oxidative Stress in Adult Patients With Type 2 Diabetes

Abstract

Objectives: Diabetic foot ulcer (DFU) is a common and major manifestation in patients with diabetes. Oxidative stress (OS) plays an important role in diabetic complications, such as DFU. Nitric oxide deficiency contributes to the impairment of diabetic wound healing. The aim of this study was to examine the association between the eNOS Glu298Asp polymorphism and DFU and oxidative stress in patients with type 2 diabetes mellitus in an Iranian population.

Methods: In this case-control study, 123 patients with type 2 diabetes and DFU and 134 patients without DFU were recruited. The genotypes of eNOS Glu298Asp polymorphism in exon 7 were determined by the polymerase chain reaction-restriction fragment length polymorphism analysis. We measured the levels of thiobarbituric reactive substances and ferric-reducing ability of plasma as the potential markers of OS.

Results: There were significant differences in genotype frequencies of eNOS Glu298Asp polymorphism between case and control groups (GG+TG vs. TT; p=0.002; OR=0.22, 95% CI 0.83 to 0.62). Also, the frequency of the T allele in cases was less common than in controls (p=0.004). There was no significant difference in levels of OS parameters and various genotypes (p>0.05).

Conclusions: These results imply that the T allele might be protective against DFU.

Keywords: diabetic foot ulcer; diabète de type 2; eNOS; oxidative stress; polymorphism; polymorphisme; stress oxydatif; type 2 diabetes; ulcère du pied diabétique.