The relationship between circulating endothelial microparticles and arterial stiffness and atherosclerosis in children with chronic kidney disease

Abstract
Endothelial dysfunction is an important factor in the pathogenesis of atherosclerosis, and endothelial microparticles (EMPs) are considered as markers of endothelial dysfunction. In this study, we aimed to examine the relationship between EMPs and arterial stiffness and atherosclerosis in children with chronic kidney disease (CKD).This cross-sectional study included 37 dialysis patients (12 haemodialysis, 25 peritoneal dialysis), 33 pre-dialysis patients and 18 healthy controls. Both in vivo and in vitro (HUVECs) evaluations were used for the study. Circulating EMPs were measured by flow cytometry. The carotid artery intima-media thickness (cIMT) and pulse wave velocity (PWV) were measured by using high-resolution ultrasound. Study groups were compared for circulating EMP, cIMT and PWV. The relationship between EMPs and arterial stiffness and atherosclerosis was evaluated.The levels of PWV, cIMT, CD144 + EMP and CD146 + EMP in the dialysis group were significantly higher than those in the pre-dialysis and control groups (P < 0.05). Additionally, the levels of cIMT, CD144 + EMP and CD146 + EMP in the pre-dialysis group were significantly higher than those in the control group (P < 0.05). In all CKD patients, the CD144 + EMP was significantly positively associated with blood pressures, age, known duration of disease, CRP and PTH, and was significantly negatively associated with haemoglobin, GFR and albumin. The CD146 + EMP was significantly positively associated with blood pressures, age and CRP. In a multiple linear regression analysis, in the CKD group, cIMT was independently related to mean blood pressure and dialysis duration. PWV was independently related to the CD144 + EMP and mean blood pressure.Our results suggest that endothelial damage starts in the early stage of CKD, that the endothelial dysfunction becomes overt with the increase of cardiovascular risk factors and that EMPs may be a reliable marker of the subclinical atherosclerosis and arterial stiffness.