Circulating angiopoietin-2 is a marker for early cardiovascular disease in children on chronic dialysis

Authors:
Shroff RC, Price KL, Kolatsi-Joannou M, Todd AF, Wells D, Deanfield J, Johnson RJ, Rees L, Woolf AS, Long DA
In:
Source: PLoS ONE
Publication Date: (2013)
Issue: 8(2): e56273
Research Area:
Cardiovascular
Basic Research
Cells used in publication:
Endothelial, umbilical vein, human (HUVEC)
Species: human
Tissue Origin: vein
SMC, aortic (AoSMC), human
Species: human
Tissue Origin: aortic
Abstract
Cardiovascular disease (CVD) is increasingly recognised as a complication of childhood chronic kidney disease (CKD) even in the absence of diabetes and hypertension. We hypothesized that an alteration in angiopoietin-1 and -2, growth factors which regulate endothelial and vascular function could be involved. We report that the endothelial survival factor, angiopoietin-1 is low in children with pre-dialysis CKD whereas the pro-inflammatory angiopoietin-2 is elevated in children on dialysis. In dialysis patients, angiopoietin-2 positively correlated with time on dialysis, systolic blood pressure, and carotid artery intima media thickness. Elevated angiopoietin-2 levels in dialysis versus pre-dialysis CKD patients were also associated with an anti-angiogenic (high soluble VEGFR-1 and low VEGF-A) and pro-inflammatory (high urate, E-selectin, P-selectin and VCAM-1) milieu. Ang-2 was immunodetected in arterial biopsy samples whilst the expression of VEGF-A was significantly downregulated in dialysis patients. Serum urate correlated with angiopoietin-2 levels in dialysis patients and addition of uric acid was able to induce rapid release of angiopoietin-2 from cultured endothelial cells. Thus, angiopoietin-2 is a marker for cardiovascular disease in children on chronic dialysis and may act as an anti-angiogenic and pro-inflammatory effector in this context. The possibility that the release of angiopoietin-2 from endothelia is mediated by urate should be explored further.