Association between nitrated lipoproteins and vascular function in type 2 diabetes

Higher levels of nitrated lipoproteins (NT-HDL and NT-LDL) were found in blood and atherosclerotic plaques of patients with coronary artery disease. We aimed to examine the relationship between plasma NT-HDL and NT-LDL and diabetic vascular dysfunction. The study included 125 African-American patients with T2DM. NT-HDL and NT-LDL were quantified by ELISA. Microvascular function was assessed by vascular reactivity index (VRI). Large artery stiffness was assessed by carotid-femoral pulse wave velocity (PWV). Carotid intima-media thickness (CIMT) was assessed by B-mode ultrasound imaging. In univariate analysis, NT-HDL was associated with VRI in total population and in patients with HbA1c ≤7.0% (β= -0.178, p= 0.034; β= -0.265, p= 0.042; respectively). In contrast, NT-LDL was associated with CIMT in total population and in patients with HbA1c >7.0% (β= -0.205, p= 0.022; β= -0.244, p= 0.042; respectively). Multivariable-adjusted regression analysis demonstrated that NT-HDL independently predicted VRI outcome in total population and in well-controlled patients (β= -0.282, p= 0.014; β= -0.400, p= 0.035, respectively). These results suggest that NT-HDL could be used as marker to identify diabetic patients at risk of developing early microvascular complications.