title: OxLDL stimulates Id1 nucleocytoplasmic shuttling in endothelial cell angiogenesis via PI3K pathway.
abstract: Angiogenesis plays remarkable roles in the development of atherosclerotic rupture plaques. However, its essential mechanism remains unclear. The purpose of the study was to investigate whether inhibitor of DNA binding-1 or inhibitor of differentiation 1 (Id1) promoted angiogenesis when exposed to oxidised low-density lipoprotein (oxLDL), and to determine the molecular mechanism involved. Using aortic ring assay and tube formation assay as a model system, a low concentration of oxLDL was found to induce angiogenic sprouting and capillary lumen formation of endothelial cell. But the Id1 expression was significantly upregulated by oxLDL at low and high concentrations. The Id1 was localised in the nuclei of the human umbilical vein endothelial cells in the control group and in the high-concentration oxLDL group. Id1 was translocated to the cytoplasm at low oxLDL concentrations. The nucleocytoplasmic shuttling at low oxLDL concentration was inhibited by treatment with the nuclear export inhibitor leptomycin B. Protein kinase A (PKA) inhibitor H89 promoted nuclear export of Id1, and phosphatidylinositol-3-kinase (PI3K) inhibitor LY294002 reduced the nuclear export of Id1. PI3K inhibition blocked oxLDL-induced angiogenesis. Low concentrations of oxLDL promoted angiogenic sprouting and capillary formation. And this process depends on nuclear export of Id1, which in turn is controlled by the PI3K pathway. This report presents a new link between oxLDL and Id1 localisation, and may provide a new insight into the interactions of ox-LDL and Id1 in the context of atherosclerosis.
authors: Key Laboratory of Biorheological Science and Technology, Ministry of Education, Chongqing Engineering Laboratory in Vascular Implants, Bioengineering College of Chongqing University, China.
authors: Juhui
authors: J
authors: Qiu
authors: Qin
authors: Q
authors: Peng
authors: Yiming
authors: Y
authors: Zheng
authors: Jianjun
authors: J
authors: Hu
authors: Xiangdong
authors: X
authors: Luo
authors: Yanqun
authors: Y
authors: Teng
authors: Tao
authors: T
authors: Jiang
authors: Tieying
authors: T
authors: Yin
authors: Chaojun
authors: C
authors: Tang
authors: Guixue
authors: G
authors: Wang
mesh_terms: D021581:Active Transport, Cell Nucleus / Q000187:drug effects; D002467:Cell Nucleus / Q000378:metabolism*; D002478:Cells, Cultured; D017868:Cyclic AMP-Dependent Protein Kinases / Q000502:physiology; D005231:Fatty Acids, Unsaturated / Q000494:pharmacology; D061307:Human Umbilical Vein Endothelial Cells / Q000502:physiology*; D006801:Humans; D051798:Inhibitor of Differentiation Protein 1 / Q000378:metabolism*; D008077:Lipoproteins, LDL / Q000494:pharmacology*; D018919:Neovascularization, Physiologic / Q000187:drug effects*; D019869:Phosphatidylinositol 3-Kinases / Q000502:physiology*; D015398:Signal Transduction / Q000187:drug effects*
chemical_list: D005231:Fatty Acids, Unsaturated; C497453:ID1 protein, human; D051798:Inhibitor of Differentiation Protein 1; D008077:Lipoproteins, LDL; C099252:oxidized low density lipoprotein; D019869:Phosphatidylinositol 3-Kinases; D017868:Cyclic AMP-Dependent Protein Kinases; C038753:leptomycin B