The pattern of circulating microparticles in patients with diabetes mellitus with asymptomatic atherosclerosis

Abstract
Background: Accelerating atherosclerosis in type 2 diabetes mellitus (T2DM) patients may relate to imbalance between pattern of microparticles (MPs), which are frequently involved in repair of vasculature, tissue injury, inflammation and thrombosis. The aim of the study was to investigate the pattern of circulating MPs in T2DM patients with asymptomatic atherosclerosis. Methods: A total of 103 patients with T2DM (54 subjects without documented coronary atherosclerosis and 49 patients with angiographic evidence of asymptomatic coronary atherosclerosis) who were underwent a contrast-enhanced multispiral computed tomography angiography and 35 healthy volunteers were enrolled in the study. To determine circulating biomarkers, blood samples were collected at baseline. MPs were labelled and characterized by flow cytometry. Results: There were no significant differences between healthy volunteers and T2DM patients in circulating numbers of MPs labelled as CD41a+, CD64+, CD144+, CD144+/CD31+, Annexin V+, CD144+/annexin V+ and CD144+/CD31+/annexin V+. However, lower number of MPs with immune phenotypes CD62E+, CD105E+ and higher numbers of CD31+/annexin V+ MPs were reported in T2DM patients when compared with healthy volunteers. Therefore, we found an increased level of circulating CD41a+ MPs, CD144+/CD31+ MPs, CD31+/annexin V+ MPs, and decreased level of CD62E+ MPs in T2DM patients with asymptomatic coronary atherosclerosis in comparison with those who had no asymptomatic atherosclerosis. Using multivariate log regression analysis, BMI (odds ratio [OR] = 1.04, p = 0.001), LDL-C (OR = 1.05, p = 0.046), hs-CRP (OR = 1.07, p = 0.044), osteoprotegerin (OR = 1.07, p = 0.026), CD62E+ MPs (OR = 1.07, p = 0.001) and CD31+/annexin V+ MPs (OR = 1.12, p = 0.003) were determined independent predictive factors of asymptomatic atherosclerosis in T2DM patients. Conclusion: Circulating levels of MP originated from apoptotic endothelial cell-derived were significantly increased in diabetic patients as compared with normal subjects, but level of activated endothelial cell-derived MPs was lower than in healthy volunteers. Among T2DM patients, an increased level of CD31+/annexin V+ MPs and decreased CD62E+ MPs were significantly associated with asymptomatic atherosclerosis.