Lipide profile, antioxidant factors and endothelial function in children and adolescent with type 1 diabetes mellitus

Type 1 diabetes mellitus (T1DM) is associated with the development of micro- and macro-vascular complication generally related to the duration of disease and glycemic control. Chronic hyperglycemia increases production of free radical intermediates which in turn augments oxidative stress. The oxidative stress can play a key role in the development of diabetic complications affecting also vascular function.In this study we evaluated the lipid profile, the parameters related to oxidative stress and the endothelial function to assess the relationships between these parameters and metabolic control in children and adolescents with T1DM. A total of 58 T1DM patient (11,5±3,49 yr) and 36 healthy children (9,60±3,21 yr) were studied.In all children serum concentration of total cholesterol (TC), low-density lipoprotein-cholesterol (LDL-C), high-density lipoprotein-cholesterol (HDL-C), triglycerides (TG), Lipoprotein(a) (Lp(a)), homocysteine, fibrinogen, MDA, Vitamin E (VitE), beta-carotene, lycopene, retinol, Vitamin C reduced (Vit C-Red) and oxidized (VitC-Oxid) and hemoglobin glycosilated (HbA1c) were measured. Vascular function was assessed by measurement of endothelium-dependent vasodilatation of brachial artery (FMD) using a high-sensibility of ultrasound system. There were no significant difference in the levels of TC, LDL-C and HDL-C between diabetic patients and the controls. Serum concentrations of TG in T1DM subjects were significantly lower than in control ones. Total antioxidant status (VitE, beta-carotene, lycopene, retinol, Vit C-Red) don't showed significant difference between groups. Only levels of VitC-Oxid were significant higher in patiens with T1DM. Moreover, prepuberal T1DM subjects showed higher MDA serum concentration than controls (p<0,01). FMD (7.99±1.06%) was impaired in 46% of T1DM subjects. There was negative correlation between FMD and serum levels of LDL-C. In our T1DM patients the glycemic control (mean value of HbA1c= 8,33%) was associated with normal lipid profile and normal antioxidant levels. Despite of these data diabetic patients show increased oxidative parameters (MDA, VitC-Oxid). Even if FMD was not apparently related to antioxidant status, the relationship with lipid values emphasizes the role of a global metabolic control to optimize the vascular health of these patients.