Quantitative and functional characteristics of endothelial progenitor cells in newly diagnosed hypertensive patients.

Populations of peripheral blood CD34(+) cells comprise precursors of endothelial cells. These precursors are crucial to cardiovascular homeostasis. Hypertension, as one of the main risk factors for cardiovascular disease, is associated with the loss of endothelium structural integrity and its functional impairment. The aim of our study was to evaluate the subsets of endothelial precursor cells in patients with newly diagnosed arterial hypertension. Twenty-four newly diagnosed, previously untreated hypertensive patients aged 59.5 ± 12.5 years, were enrolled into the study group, whereas the control group comprised 45 healthy subjects, 55.5±10.0 years old. Endothelial progenitor cells (EPCs) were analysed by flow cytometry. The results showed that hypertensive patients were characterized by a significantly higher percentage and number of the CD34(+) cells and simultaneously less differentiated CD34(+)CD45(dim/neg)CD133(+) progenitors. The percentage and number of CD34(+)CD45(neg)VEGFR2(+) and CD34(+)CD45(neg)CD133(+)VEGFR2(+) cells were not different from the control group. Moreover, patients had a significantly lower percentage and number of the CD34(+)CD45(neg)VEGFR2(+)CXCR4(+) and CD34(+)CD45(neg)VEGFR2(+)ICAM-1(+) cells than healthy individuals. These changes were paralleled by early symptoms of nephropathy, that is, lower glomerular filtration rate (GFR) values and borderline micro albuminuria. Our results indicate that an elevation in the number of less differentiated progenitors may be a mechanism compensating for defects of migration and adhesion, present in a more differentiated subset.