Control of angiogenesis by AIBP-mediated cholesterol efflux

Article

关键词: EMBRYONIC VASCULAR DEVELOPMENT;    CASSETTE TRANSPORTER 1;    I BINDING-PROTEIN;    ENDOTHELIAL-CELLS;    TANGIER-DISEASE;    ZEBRAFISH;    EXPRESSION;    ABCG1;    GENE;    ACTIVATION;   

DOI  :  10.1038/nature12166

来源: SCIE

【 摘 要 】

Cholesterol is a structural component of the cell and is indispensable for normal cellular function, although its excess often leads to abnormal proliferation, migration, inflammatory responses and/or cell death. To prevent cholesterol overload, ATP-binding cassette (ABC) transporters mediate cholesterol efflux from the cells to apolipoprotein A-I (apoA-I) and the apoA-I-containing high-density lipoprotein (HDL)(1-3). Maintaining efficient cholesterol efflux is essential for normal cellular function(4-6). However, the role of cholesterol efflux in angiogenesis and the identity of its local regulators are poorly understood. Here we show that apoA-I binding protein (AIBP) accelerates cholesterol efflux from endothelial cells to HDL and thereby regulates angiogenesis. AIBP- and HDL-mediated cholesterol depletion reduces lipid rafts, interferes with VEGFR2 (also known as KDR) dimerization and signalling and inhibits vascular endothelial growth factor-induced angiogenesis in vitro and mouse aortic neovascularization ex vivo. Notably, Aibp, a zebrafish homologue of human AIBP, regulates the membrane lipid order in embryonic zebrafish vasculature and functions as a non-cell-autonomous regulator of angiogenesis. aibp knockdown results in dysregulated sprouting/branching angiogenesis, whereas forced Aibp expression inhibits angiogenesis. Dysregulated angiogenesis is phenocopied in Abca1 (also known as Abca1a) Abcg1-deficient embryos, and cholesterol levels are increased in Aibp-deficient and Abca1Abcg1-deficient embryos. Our findings demonstrate that secreted AIBP positively regulates cholesterol efflux from endothelial cells and that effective cholesterol efflux is critical for proper angiogenesis.

【 授权许可】

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