Purinergic signaling in endothelial cells.

由于细胞对各种促炎刺激、组织损伤和细胞死亡的反应，细胞外三和二磷酸核苷被释放到组织液和血浆中。胞外核苷酸通过嘌呤能P2受体作用于多种细胞，引起细胞活化和凋亡。我们的研究结果表明，细胞外ATP诱导内皮细胞(EC)激活和磷酸化几种蛋白，包括粘着斑激酶(FAK)、巴西林、相关粘着斑酪氨酸激酶(RAFTK)、p130/cas、小窝蛋白-1、Shc和p38、SAPK/JNK和ERK MAP激酶。这些蛋白属于多种信号转导通路，与细胞骨架重排、细胞扩散、运动、细胞增殖和细胞凋亡有关。我们还发现，细胞外核苷酸激活核因子-kappaB(NF-kappaB)和上调E-选择素的表达，参与白细胞与EC的初始相互作用，导致它们向炎症部位迁移。我们试图确定E-选择素上调的受体(S)，并阐明三磷酸腺苷诱导的信号转导导致E-选择素基因诱导的机制。所获得的结果将有助于阐明涉及嘌呤能受体信号转导的疾病状态(如炎症、血管生成、动脉粥样硬化、移植物排斥反应)的机制。关于E-选择素调节机制的新发现，包括揭示P2受体激活p38MAPK和NF-kappaB的来源的数据，将定义细胞外核苷酸在炎症和其他疾病中的作用。已完成的研究将提供如何控制P2受体功能的新方法，这些方法可以通过抗血管生成治疗在血管炎症、血栓形成、囊性纤维化和癌症的治疗中有用。

Extracellular tri- and diphosphate nucleosides are released into tissue fluids and plasma as a consequence of cellular responses to various pro- inflammatory stimuli, tissue damage and cell death. Extracellular nucleotides exert their effects on various cells through purinergic P2 type receptors and can cause cell activation and apoptosis. Our data show that extracellular ATP induces endothelial cell (EC) activation and phosphorylation of several proteins in EC, including focal adhesion kinase (FAK), paxillin, related adhesion focal tyrosine kinase (RAFTK), p130/cas, caveolin-1,Shc, and p38, SAPK/JNK and ERK MAP kinases. These proteins belong to various signal transduction pathways associated with cell cytoskeleton rearrangements, cell spreading, motility, cell proliferation, and apoptosis. We also found that extracellular nucleotides activate nuclear factor kappa B (NF-kappaB) and up-regulated expression of E-selectin, involved in the initial interaction of leukocytes with EC, leading to their transmigration into spots of inflammation. We intend to identify the receptor(s) responsible for up-regulation of the E- selectin and elucidate the mechanism of ATP-induced signal transduction leading to induction of E-selectin gene. Obtained results will help to elucidate the mechanisms of disease states that involve purinergic receptor signaling (e.g, inflammation, angiogenesis, atherogenesis, graft rejection). New findings about the mechanism of E- selectin regulation, including data revealing the origin of the activation of p38 MAPK and NF-kappaB by P2 receptors, will define the role of extracellular nucleotides in inflammation and other diseases. Completed studies should offer novel approaches how to control P2 receptors functions that can be useful in the treatment of vascular inflammation, thrombosis, cystic fibrosis and cancer through anti-angiogenic therapies.