An Observational Cross-sectional Study to Compare Carbamylated High-density Lipoprotein Levels Among Normal Subjects, Type 2 Diabetes Mellitus Patients With and Without Coronary Heart Disease.

High-density lipoprotein (HDL) is involved in various atheroprotective processes, including reverse cholesterol transport, inhibition of lipid oxidation and inflammatory cytokine secretion, endothelial repair, and antiapoptotic function, which all contribute to the regression of plague burden. Recent studies have shown that oxidative stress and chronic inflammation - both implicated in the process of diabetes - can contribute to an irreversible post-translational modification called carbamylation. Carbamylation levels reflect the burden of enhanced inflammation, oxidative stress, and renal impairment, and can serve as a biomarker of certain pathological conditions. Several clinical studies have demonstrated positive associations between cardiovascular risk, mortality, and serum carbamylation-derived product levels in the general population and particularly in patients with kidney failure. Increasing evidence also shows that carbamylated lipoprotein plays a pivotal role in atherosclerosis.18 However, most studies concerning carbamylation have been performed under a kidney disease background. Whether HDL particles in patients with type 2 diabetes mellitus (T2DM) show enhanced carbamylation and whether this enhancement is associated with vascular complications remains unknown. Thus, in the present study, the investigators aim to test whether HDL experiences carbamylation in T2DM patients and investigated the pro-atherogenic effects of carbamylated HDL on endothelial-monocyte adhesion.