Endocrine Abstracts

Introduction: Many studies have found that markers of oxidative stress (OS) are significantly increased in diabetes mellitus, but only a limited number of studies describe the disturbance of OS in pre-diabetes.

Objective: To study the state of the glutathione system in patients with disorders of carbohydrate metabolism and concomitant diseases of the cardiovascular system (CVS).

Materials and methods: 181 patients were included under the age of 55 years: group 1–27 patients with newly diagnosed pre-diabetes without concomitant CVS diseases, group 2–28 patients with newly diagnosed pre-diabetes and the presence of concomitant IHD, group 3–20 patients with newly diagnosed pre-diabetes and the presence of concomitant IHD and peripheral vessels atherosclerosis, group 4–47 patients with type 2 diabetes (T2D), group 5–59 practically healthy persons. The total glutathione (GSHt) and glutathione in the oxidized form (GSSG) contained in the erythrocytes were measured by a glutathione reductase reaction. The redox potential of glutathione (Eh) of erythrocytes was determined by the Nernst equation.

Results: In group 1 GSHt and GSH were significantly lower, compared with group 3 (p_1-3=0.012, p_1-3=0.053, respectively). When compared with the group group 4, a significantly higher GSH content was detected (p_1-4=0.068). In the group 4 there was a significant decrease in GSH and 2GSH + GSSG, and an increase in GSSG, compared to group 2, group 3 and group 5 (p_4-2=0.006, p_4-3=0.006, p_4-5=0.003, p_4-2=0.005, p_4-3=0.009, p_4-5=0.014, respectively, and p_4-2=0.005, p_4-3=0.016, p_4-5=0.001, respectively). According to the results of the study, the highest concentration of glutathione (5.11 [1.98, 5.78]) was in the group 2. The presence of concomitant IHD decreases the ability of glutathione to recover, as evidenced by the significantly lower values of GSH and GSHt in group 4, compared to group 1 (p_4-1=0.004, p_4-1=0.016, respectively), and an increase GSSG (p_4-1=0.004). Eh was significantly higher in group 4 than in groups of 1,2,5 (p_4-1=0.035, p_4-2=0.013, and p_4-5=0.055).

The conclusion: The state of the glutathione system can be considered as one of the markers of vascular lesion in patients with prediabetes. At the stage of pre-diabetes, the patient rarely has complaints typical of cardiovascular diseases. However, at this stage, the mechanisms that lead to the development of complications in the subsequent already type 2 diabetes mellitus begin to form.