Modulation of endothelial cell proliferation and capillary network formation by the ox-LDL component: 1-palmitoyl-2-archidonoyl-sn-glycero-3-phosphocholine (ox-PAPC).

Atherosclerotic plaque formation is often associated with pathological angiogenesis. Modified phospholipids, including oxidized lipoproteins such as LDL, are found to induce adhesion of the monocytes to the endothelial cells and to stimulate their chemotaxis. Effects of oxidized 1-palmitoyl-2-archidonoyl-sn-glycero-3-phosphocholine (ox-PAPC) mimic actions of minimally modified LDL in vivo. Interleukin-8 (IL-8) and interleukin-15 (IL-15) are known to induce both inflammation and angiogenesis. The goal of our study was to analyze a potential synergism between ox-PAPC and IL-15 in the in vitro model of angiogenesis carried out in the human endothelial cells (HUVECs). Increasing IL-15 concentrations led to formation of the tube-like structures in the matrigel 3D-model of angiogenesis (P < 0.05), in contrast to ox-PAPC that inhibited this process. HUVECs incubation with ox-PAPC led to reduced IL-15 gene basal expression (P = 0.033) along with parallel increase, however statistically insignificant, of basal gene expression of IL-8 (P = 0.086). Our findings point to the ox-PAPC opposite effects on the IL-8- and IL-15-mediated angiogenic responses that contribute to pathological angiogenesis induced by ox-LDL.