High‐density lipoprotein exerts vasculoprotection via endothelial progenitor cells

V Petoumenos, G Nickenig… - Journal of cellular and …, 2009 - Wiley Online Library
V Petoumenos, G Nickenig, N Werner
Journal of cellular and molecular medicine, 2009Wiley Online Library
Endothelial progenitor cells (EPC) enhance endothelial cell repair, improve endothelial
dysfunction and are a predictor for cardiovascular mortality. High‐density lipoprotein (HDL)
cholesterol levels inversely correlate with cardiovascular events and have vasculoprotective
effects. Here we postulate that HDL influences EPC biology. HDL and EPC were isolated
according to standard procedures. Differentiation of mononuclear cells into DiLDL/lectin
positive cells was enhanced after HDL treatment compared to vehicle. HDL was able to …
Abstract
Endothelial progenitor cells (EPC) enhance endothelial cell repair, improve endothelial dysfunction and are a predictor for cardiovascular mortality. High‐density lipoprotein (HDL) cholesterol levels inversely correlate with cardiovascular events and have vasculoprotective effects. Here we postulate that HDL influences EPC biology. HDL and EPC were isolated according to standard procedures. Differentiation of mononuclear cells into DiLDL/lectin positive cells was enhanced after HDL treatment compared to vehicle. HDL was able to inhibit apoptosis (TUNEL assay, annexin V staining) while proliferation (BrdU incorporation) of early outgrowth colonies after extended cell cultivation (14 days) was increased. Flow chamber experiments revealed an improved adhesion of HDL pre‐incubated EPC on human coronary artery endothelial cells (HCAEC) compared to vehicle while HDL treatment of HCAEC prevented adhesion of inflammatory cells. Flow cytometry demonstrated an up‐regulation of β2‐ and α4‐integrins on HDL pre‐incubated EPC. Blocking experiments revealed a unique role of β2‐integrin in EPC adhesion. Treatment of wild‐type mice with recombinant HDL after endothelial denudation resulted in enhanced re‐endothelialization compared to vehicle. Finally, in patients with coronary artery disease a correlation between circulating EPC and HDL concentrations was demonstrated. We provide evidence that HDL mediates important vasculoprotective action via the improvement of function of circulating EPC.
Wiley Online Library