Department of Experimental Medicine, 'Sapienza' University of Rome, Rome, Italy.
Department of Cardiovascular, Dysmetabolic and Aging-associated Diseases, Istituto Superiore di Sanità, Rome, Italy.
Thromb Haemost. 2019 May;119(5):726-734. doi: 10.1055/s-0039-1678707. Epub 2019 Feb 13.
Chronic treatment with aspirin in healthy volunteers (HVs) is associated with recovery of adenosine diphosphate (ADP)-induced platelet activation. The purinergic P2Y receptor exerts its effects via a G-protein, which is the same biochemical pathway activated by thromboxane-A2 receptor. We hypothesized that recovery of ADP-induced platelet activation could be attributed to increased P2Y expression induced by chronic aspirin exposure. We performed a multi-phase investigation which embraced both in vitro and in vivo experiments conducted in (1) human megakaryoblastic DAMI cells, (2) human megakaryocytic progenitor cell cultures, (3) platelets obtained from HVs treated with aspirin and (4) platelets obtained from aspirin-treated patients. DAMI cells treated with aspirin or WY14643 (PPARα agonist) had a significant up-regulation of P2Y mRNA, which was shown to be a PPARα-dependent process. In human megakaryocytic progenitors, in the presence of aspirin or WY14643, P2Y mRNA expression was higher than in mock culture. P2Y expression increased in platelets obtained from HVs treated with aspirin for 8 weeks. Platelets obtained from patients who were on aspirin for more than 2 months had increased P2Y expression and ADP-induced aggregation compared with patients on aspirin treatment for less than a month. Overall, our results suggest that aspirin induces genomic changes in megakaryocytes leading to P2Y up-regulation and that PPARα is the nuclear receptor involved in this regulation. Since P2Y is coupled to the same G-protein of thromboxane-A2 receptor, platelet adaptation in response to pharmacological inhibition seems not to be receptor specific, but may involve other receptors with the same biochemical pathway.
在健康志愿者（HV）中进行慢性阿司匹林治疗与恢复二磷酸腺苷（ADP）诱导的血小板激活有关。嘌呤能 P2Y 受体通过 G 蛋白发挥其作用，该 G 蛋白与血栓烷 A2 受体激活的生化途径相同。我们假设，ADP 诱导的血小板激活的恢复可能归因于慢性阿司匹林暴露诱导的 P2Y 表达增加。我们进行了多阶段研究，包括（1）人巨核母细胞 DAMI 细胞、（2）人巨核细胞祖细胞培养物、（3）接受阿司匹林治疗的 HV 获得的血小板和（4）接受阿司匹林治疗的患者获得的血小板中的体外和体内实验。用阿司匹林或 WY14643（PPARα 激动剂）处理的 DAMI 细胞的 P2Y mRNA 表达显著上调，这表明这是一个 PPARα 依赖性过程。在人巨核细胞祖细胞中，在阿司匹林或 WY14643 的存在下，P2Y mRNA 表达高于模拟培养物。接受阿司匹林治疗 8 周的 HV 获得的血小板中 P2Y 表达增加。接受阿司匹林治疗超过 2 个月的患者的血小板 P2Y 表达和 ADP 诱导的聚集增加，而接受阿司匹林治疗不到 1 个月的患者则没有。总体而言，我们的结果表明，阿司匹林诱导巨核细胞中的基因组变化导致 P2Y 上调，而 PPARα 是参与这种调节的核受体。由于 P2Y 与血栓烷 A2 受体的相同 G 蛋白偶联，因此血小板对药物抑制的适应似乎不是受体特异性的，而是可能涉及具有相同生化途径的其他受体。
