Objective: Circulating microvesicles, released from activated/apoptotic cells, are involved in vascular complications and may be looked upon as biomarkers. Albuminuria is characteristic of disease progression in type 2 diabetes mellitus. We aimed to investigate quantitative and qualitative differences of circulating microvesicles in type 2 diabetes mellitus with and without albuminuria and whether 12-month exercise training influenced expression of circulating microvesicles.
Methods: Coronary artery disease patients with type 2 diabetes mellitus (n = 75), of which 25 had albuminuria, were included. Annexin V+ (AV+) circulating microvesicles were analysed by flow cytometry in citrated plasma. The exercise volume was 150 min per week.
Results: In albuminuria patients, circulating microvesicles from endothelial-(CD146+/CD62E+/AV+) and endothelial-progenitor-(CD309+/CD34+/AV+) cells were significantly higher compared to those without (p ⩽ 0.01, both). Receiver operating characteristic curve analysis of the endothelial circulating microvesicles shows an area under the curve of 0.704 (95% confidence interval: 0.57-0.84; p = 0.004). Albuminuria patients had more circulating microvesicles derived from activated leukocytes and monocytes and monocytes carrying tissue factor (CD11b+/AV+, CD11b+/CD14+/AV+, CD142+/CD14+/AV+, respectively, p ⩽ 0.05, all) and higher number of circulating microvesicles from activated platelets (CD62P+/AV+). Within exercising patients, circulating microvesicles from progenitor cells increased (p = 0.023), however, not significantly different from controls.
Conclusion: Coronary artery disease patients with type 2 diabetes mellitus and albuminuria had elevated number of circulating microvesicles from activated blood and vascular cells, rendering them as potential predictors of disease severity. The circulating microvesicles were limitedly affected by long-term exercise training in our population.
Keywords: Albuminuria; exercise training; flow cytometry; microvesicles and type 2 diabetes mellitus.