Objective-The presence of kinase-insert domain-containing receptor (KDR) on circulating CD34(+) cells is assumed to be indicative for the potential of these cells to support vascular maintenance... Show moreObjective-The presence of kinase-insert domain-containing receptor (KDR) on circulating CD34(+) cells is assumed to be indicative for the potential of these cells to support vascular maintenance and repair. However, in bone marrow and in granulocyte colony-stimulating factor (G-CSF)-mobilized peripheral blood, less than 0.5% of CD34(+) cells co-express KDR. Therefore, we studied whether CD34(+)/KDR+ cells are generated in the peripheral circulation. Methods and Results-Using an ex vivo flow model, we show that activated platelets enable CD34(+) cells to home to sites of vascular injury and that upon immobilization, KDR is translocated from an endosomal compartment to the cell-surface within 15 minutes. In patients with diabetes mellitus type 2, the percentage of circulating CD34(+) co-expressing KDR was significantly elevated compared to age-matched controls. When treated with aspirin, the patients showed a 49% reduction in the generation of CD34(+)/KDR+ cells, indicating that the level of circulating CD34(+)/KDR+ cells also relates to in vivo platelet activation. Conclusion-Circulating CD34(+)/KDR+ are not mobilized from bone marrow as a predestined endothelial progenitor cell population but are mostly generated from circulating multipotent CD34(+) cells at sites of vascular injury. Therefore, the number of circulating CD34(+)/KDR+ cells may serve as a marker for vascular injury. (Arterioscler Thromb Vasc Biol. 2011;31:408-415.) Show less
OBJECTIVE The presence of kinase-insert domain-containing receptor (KDR) on circulating CD34+ cells is assumed to be indicative for the potential of these cells to support vascular maintenance and... Show moreOBJECTIVE The presence of kinase-insert domain-containing receptor (KDR) on circulating CD34+ cells is assumed to be indicative for the potential of these cells to support vascular maintenance and repair. However, in bone marrow and in granulocyte colony-stimulating factor (G-CSF)-mobilized peripheral blood, less than 0.5% of CD34+ cells co-express KDR. Therefore, we studied whether CD34+/KDR+ cells are generated in the peripheral circulation. METHODS AND RESULTS Using an ex vivo flow model, we show that activated platelets enable CD34+ cells to home to sites of vascular injury and that upon immobilization, KDR is translocated from an endosomal compartment to the cell-surface within 15 minutes. In patients with diabetes mellitus type 2, the percentage of circulating CD34+ co-expressing KDR was significantly elevated compared to age-matched controls. When treated with aspirin, the patients showed a 49% reduction in the generation of CD34+/KDR+ cells, indicating that the level of circulating CD34+/KDR+ cells also relates to in vivo platelet activation. CONCLUSIONS Circulating CD34+/KDR+ are not mobilized from bone marrow as a predestined endothelial progenitor cell population but are mostly generated from circulating multipotent CD34+ cells at sites of vascular injury. Therefore, the number of circulating CD34+/KDR+ cells may serve as a marker for vascular injury. Show less
Solingen, C. van; Monge, M.; Vries, D.K. de; Seghers, L.; Vries, M.R. de; Bijkerk, R.; ... ; Zonneveld, A.J. van 2010
To investigate the association of office and ambulatory 24-h pulse pressure (PP) with clinical characteristics and cardiovascular risk factors in normoalbuminuric type 2 diabetic patients enrolled... Show moreTo investigate the association of office and ambulatory 24-h pulse pressure (PP) with clinical characteristics and cardiovascular risk factors in normoalbuminuric type 2 diabetic patients enrolled to the Randomised Olmesartan and Diabetes Microalbuminuria Prevention study, 4449 patients (2054 male and 2395 female; mean age 57.7±8.7 years) with type 2 diabetes, normoalbuminuria and at least one additional cardiovascular risk factor were included into the analysis. After adjustment by age, there were significant correlations between office PP and presence of hypertension (r=0.24; P<0.001), presence of cardiac and vascular disorders (r=0.17; P<0.001), metabolic syndrome (r=0.10; P<0.001), duration of diabetes (r=0.09; P<0.001), fasting blood glucose (r=0.08; P<0.001), albumin/creatinine ratio (r=0.07; P<0.001), insulin treatment, glycosylated haemoglobin (HbA1c), male gender and current smoking. In the subgroup of 1234 patients with ambulatory blood pressure measurement performed, ambulatory PP adjusted for office PP correlated with fasting blood glucose (r=0.16; P<0.001), metabolic syndrome (r=0.14; P<0.001), albumin/creatinine ratio (r=0.11; P<0.001) and indices of glycemic control (HbA1c: r=0.11; P<0.001). In this group of normoalbuminuric type 2 diabetic patients, office and ambulatory PP were associated with duration of diabetes, indices of glycemic control and cardiovascular risk factors. There was relationship between office and ambulatory PP and albuminuria even within normal albuminuria range.Journal of Human Hypertension advance online publication, 9 December 2010; doi:10.1038/jhh.2010.111. Show less
In contrast to microalbuminuric type 2 diabetic patients, the factors correlated with urinary albumin excretion are less well known in normoalbuminuric patients. This may be important because even... Show moreIn contrast to microalbuminuric type 2 diabetic patients, the factors correlated with urinary albumin excretion are less well known in normoalbuminuric patients. This may be important because even within the normoalbuminuric range, higher rates of albuminuria are known to be associated with higher renal and cardiovascular risk. At the time of screening for the Randomised Olmesartan and Diabetes Microalbuminuria Prevention (ROADMAP) Study, the urinary albumin/creatinine ratio (UACR) was 0.44 mg/mmol in 4,449 type 2 diabetic patients. The independent correlates of UACR were analysed. Independent correlates of UACR during baseline were (in descending order): night-time systolic BP (r (s) = 0.19); HbA(1c) (r (s) = 0.18); mean 24 h systolic BP (r (s) = 0.16); fasting blood glucose (r (s) = 0.16); night-time diastolic BP (r (s) = 0.12); office systolic BP, sitting (r (s) = 0.11), standing (r (s) = 0.10); estimated GFR (r (s) = 0.10); heart rate, sitting (r (s) = 0.10); haemoglobin (r (s) = -0.10); triacylglycerol (r (s) = 0.09); and uric acid (r (s) = -0.08; all p a parts per thousand currency signaEuro parts per thousand 0.001). Significantly higher albumin excretion rates were found for the following categorical variables: higher waist circumference (more marked in men); presence of the metabolic syndrome; smoking (difference more marked in males); female sex; antihypertensive treatment; use of amlodipine; insulin treatment; family history of diabetes; and family history of cardiovascular disease (more marked in women). Although observational correlations do not prove causality, in normoalbuminuric type 2 diabetic patients the albumin excretion rate is correlated with many factors that are potentially susceptible to intervention. ClinicalTrials.gov ID no.: NCT00185159 This study was sponsored by Daichii-Sankyo. Show less
