Arterial stiffness in hypertensives in relation to expression of angiopoietin-1 and 2 genes in peripheral monocytes
Angiopoietins (Angs) are important angiogenic and endothelial cell growth factors with many functions, including influence on the vascular wall. Pulse-wave velocity (pwv) is an independent marker of cardiovascular adverse outcome in hypertensives, although all the pathophysiological mechanisms that affect it have not yet been determined. We investigated the relationship between arterial stiffness and Ang-1 and Ang-2 gene expression in the peripheral blood monocytes of hypertensive patients. We studied 53 patients who had untreated grade-1 or grade-2 essential hypertension and no indications of other organic heart disease. Carotid–femoral (c–f) and carotid–radial (c–r) artery waveforms were measured and pwv was determined. The monocytes were isolated using anti-CD14+ antibodies and mRNAs were estimated by real-time quantitative reverse transcription–PCR. Ang-1 gene expression was strongly correlated with both c–f-pwv (r=0.952, P<0.001) and c–r-pwv (r=0.898, P<0.001). Similarly, Ang-2 gene expression was significantly correlated with both c–f-pwv (r=0.471, P=0.002) and c–r-pwv (r=0.437, P=0.003). Our data provide important evidence that Ang-1 and Ang-2 gene expression levels in peripheral monocytes are closely related with pwv in patients with essential hypertension. This positive correlation may suggest a link between angiogenesis and arterial stiffness in those patients.