Touat-Hamici Zahia, Weidmann Henri, Blum Yuna, Proust Carole, Durand Hervé, Iannacci Francesca, Codoni Veronica, Gaignard Pauline, Thérond Patrice, Civelek Mete, Karabina Sonia A, Lusis Aldons J, Cambien François, Ninio Ewa
Sorbonne Universités, UPMC, INSERM UMR_S 1166, ICAN, Genomics and Pathophysiology of Cardiovascular Diseases Team, 91 Bd de l'Hôpital, 75013 Paris, France
Sorbonne Universités, UPMC, INSERM UMR_S 1166, ICAN, Genomics and Pathophysiology of Cardiovascular Diseases Team, 91 Bd de l'Hôpital, 75013 Paris, France.
Cardiovasc Res. 2016 Dec;112(3):702-713. doi: 10.1093/cvr/cvw217. Epub 2016 Sep 30.
Lipid phosphate phosphatase 3; type 2 phosphatidic acid phosphatase β (LPP3; PPAP2B) is a transmembrane protein dephosphorylating and thereby terminating signalling of lipid substrates including lysophosphatidic acid (LPA) and sphingosine-1-phosphate (S1P). Human LPP3 possesses a cell adhesion motif that allows interaction with integrins. A polymorphism (rs17114036) in PPAP2B is associated with coronary artery disease, which prompted us to investigate the possible role of LPP3 in human endothelial dysfunction, a condition promoting atherosclerosis.
To study the role of LPP3 in endothelial cells we used human primary aortic endothelial cells (HAECs) in which LPP3 was silenced or overexpressed using either wild type or mutated cDNA constructs. LPP3 silencing in HAECs enhanced secretion of inflammatory cytokines, leucocyte adhesion, cell survival, and migration and impaired angiogenesis, whereas wild-type LPP3 overexpression reversed these effects and induced apoptosis. We also demonstrated that LPP3 expression was negatively correlated with vascular endothelial growth factor expression. Mutations in either the catalytic or the arginine-glycine-aspartate (RGD) domains impaired endothelial cell function and pharmacological inhibition of S1P or LPA restored it. LPA was not secreted in HAECs under silencing or overexpressing LPP3. However, the intra- and extra-cellular levels of S1P tended to be correlated with LPP3 expression, indicating that S1P is probably degraded by LPP3.
We demonstrated that LPP3 is a negative regulator of inflammatory cytokines, leucocyte adhesion, cell survival, and migration in HAECs, suggesting a protective role of LPP3 against endothelial dysfunction in humans. Both the catalytic and the RGD functional domains were involved and S1P, but not LPA, might be the endogenous substrate of LPP3.
脂质磷酸酶3；2型磷脂酸磷酸酶β（LPP3；PPAP2B）是一种跨膜蛋白，可使包括溶血磷脂酸（LPA）和1-磷酸鞘氨醇（S1P）在内的脂质底物去磷酸化，从而终止其信号传导。人LPP3具有一个细胞粘附基序，可与整合素相互作用。PPAP2B基因中的一个多态性（rs17114036）与冠状动脉疾病相关，这促使我们研究LPP3在人类内皮功能障碍（一种促进动脉粥样硬化的病症）中可能发挥的作用。
为了研究LPP3在内皮细胞中的作用，我们使用了人原代主动脉内皮细胞（HAEC），通过野生型或突变的cDNA构建体使LPP3沉默或过表达。HAEC中LPP3的沉默增强了炎性细胞因子的分泌、白细胞粘附、细胞存活和迁移，并损害了血管生成，而野生型LPP3的过表达则逆转了这些作用并诱导了细胞凋亡。我们还证明LPP3表达与血管内皮生长因子表达呈负相关。催化结构域或精氨酸-甘氨酸-天冬氨酸（RGD）结构域中的突变损害了内皮细胞功能，对S1P或LPA的药理学抑制恢复了该功能。在LPP3沉默或过表达的HAEC中未分泌LPA。然而，S1P的细胞内和细胞外水平倾向于与LPP参与，且S1P可能是LPP3的内源性底物，而LPA不是。pp3表达相关，表明S1P可能被LPP3降解。
我们证明LPP3是HAEC中炎性细胞因子、白细胞粘附、细胞存活和迁移的负调节因子，提示LPP3对人类内皮功能障碍具有保护作用。催化结构域和RGD功能结构域均
