Delta-aminolevulinate dehydratase activity and oxidative profile in pregnant women with pre-gestational type 2 diabetes and gestational diabetes

The aim of this study was to perform a comparative evaluation between pregnant women: healthy, with pre-gestational type 2 diabetes (T2DM) and gestational diabetes mellitus (GDM), to determine if diabetes mellitus developed at different times interferes with the oxidative impact on the pregnant woman maternal body. A total of 90 pregnant women were recruited in the third trimester of pregnancy, subdivided into the three groups, and evaluated through their clinical characteristics, oxidative stress markers and delta-aminolevulinate dehydratase (δ-ALA- D) activity. Pregnant women with diabetes mellitus (DM) showed an increase in: age, pre-gestational and gestational body mass index (BMI), blood pressure, blood glucose and platelet count; those with T2DM had higher pre-gestational BMI and glycated hemoglobin A1c (HbA1c). The levels of thiobarbituric acid reactive substances were higher and the levels of non-protein thiols and catalase activity were lower in the DM groups compared to the control. Vitamin C was decreased in the T2DM group. The δ-ALA-D activity was decreased in pregnant women with GDM and the rate of enzymatic reactivation was higher in the DM groups. DM presented in gestation, regardless of the moment of its development, generates increase of the oxidative stress and decrease of the antioxidant defences, representing the largest difference with the control group. It is suggested that the insulin used in the treatment of T2DM acts in a beneficial way in the δ-ALA-D activity