National Clinical Research Center for Hematologic Diseases, The First Affiliated Hospital of Soochow University, Jiangsu Institute of Hematology, Suzhou, China.
Collaborative Innovation Center of Hematology, Institute of Blood and Marrow Transplantation, Soochow University, Suzhou, China.
Thromb Haemost. 2022 Oct;122(10):1693-1705. doi: 10.1055/a-1837-7797. Epub 2022 Apr 27.
Hypoxia-inducible factor-1α (HIF-1α) involves in redox reactions. Considering the role of reactive oxygen species (ROS) in platelet function, whether it regulates platelet function remains unclear. Using an inhibitor of HIF prolyl-hydroxylase, IOX-2, we intend to investigate its effect on platelet function. Human platelets were treated with IOX-2 (0, 10, 25, and 50 μM) followed by analysis of platelet aggregation, granule secretion, receptor expression, platelet spreading, or clot retraction. Additionally, IOX-2 (10 mg/kg) was injected intraperitoneally into mice to measure tail bleeding time and arterial thrombosis. IOX-2 significantly inhibited collagen-related peptide (CRP; 0.25 μg/mL) or thrombin (0.03 U/mL)-induced platelet aggregation and ATP release dose dependently without affecting P-selectin expression and the surface levels of glycoprotein (GP)Ibα, GPVI, or αβ. In addition, IOX-2-treated platelets presented significantly decreased spreading on fibrinogen or collagen and clot retraction. Moreover, IOX-2 administration into mice significantly impaired the in vivo hemostatic function of platelets and arterial thrombus formation without affecting the number of circulating platelets and coagulation factors (FVIII and FIX). Further, IOX-2 significantly upregulated HIF-1α in platelets, decreased ROS generation, and downregulated NOX1 expression. Finally, IOX-2 increased the phosphorylation level of VASP (Ser157/239), and inhibited the phosphorylation of p38 (Thr180/Tyr182), ERK1/2 (Thr202/Tyr204), AKT (Thr308/Ser473), and PKCδ (Thr505) in CRP- or thrombin-stimulated platelets. In conclusion, inhibition of HIF prolyl-hydroxylase modulates platelet function and arterial thrombus formation, possibly through upregulation of HIF-1α expression and subsequent inhibition of ROS generation, indicating that HIF-1α might be a novel target for the treatment of thrombotic disorders.
缺氧诱导因子-1α（HIF-1α）参与氧化还原反应。考虑到活性氧（ROS）在血小板功能中的作用，它是否调节血小板功能尚不清楚。我们使用 HIF 脯氨酰羟化酶抑制剂 IOX-2，旨在研究其对血小板功能的影响。用 IOX-2（0、10、25 和 50 μM）处理人血小板，然后分析血小板聚集、颗粒分泌、受体表达、血小板铺展或凝块回缩。此外，将 IOX-2（10mg/kg）腹膜内注射到小鼠体内，测量尾部出血时间和动脉血栓形成。IOX-2 显著抑制胶原相关肽（CRP；0.25μg/mL）或凝血酶（0.03 U/mL）诱导的血小板聚集和 ATP 释放，呈剂量依赖性，而不影响 P-选择素表达和糖蛋白（GP）Ibα、GPVI 或αβ的表面水平。此外，IOX-2 处理的血小板在纤维蛋白原或胶原蛋白上的铺展明显减少，凝块回缩也减少。此外，IOX-2 给药到小鼠体内显著损害血小板的体内止血功能和动脉血栓形成，而不影响循环血小板和凝血因子（FVIII 和 FIX）的数量。此外，IOX-2 显著上调血小板中的 HIF-1α，减少 ROS 的产生，并下调 NOX1 的表达。最后，IOX-2 增加了 VASP（Ser157/239）的磷酸化水平，并抑制了 CRP 或凝血酶刺激的血小板中 p38（Thr180/Tyr182）、ERK1/2（Thr202/Tyr204）、AKT（Thr308/Ser473）和 PKCδ（Thr505）的磷酸化。总之，抑制 HIF 脯氨酰羟化酶调节血小板功能和动脉血栓形成，可能通过上调 HIF-1α 表达和随后抑制 ROS 的产生，表明 HIF-1α 可能是治疗血栓性疾病的新靶点。
