Yujiro Asada, MD, Department of Pathology, Faculty of Medicine, University of Miyazaki, 5200 Kihara, Kiyotake, Miyazaki 889-1692, Japan, Tel.: + 81 985 85 2810, Fax: + 81 985 85 7614, E-mail:
Thromb Haemost. 2015 Jul;114(1):158-72. doi: 10.1160/TH14-09-0794. Epub 2015 Apr 2.
Atherosclerotic lesions represent a hypoxic milieu. However, the significance of this milieu in atherothrombosis has not been established. We aimed to assess the hypothesis that vascular wall hypoxia promotes arterial thrombus formation. We examined the relation between vascular wall hypoxia and arterial thrombus formation using a rabbit model in which arterial thrombosis was induced by 0.5 %-cholesterol diet and repeated balloon injury of femoral arteries. Vascular wall hypoxia was immunohistochemically detected by pimonidazole hydrochloride, a hypoxia marker. Rabbit neointima and THP-1 macrophages were cultured to analyse prothrombotic factor expression under hypoxic conditions (1 % O2). Prothrombotic factor expression and nuclear localisation of hypoxia-inducible factor (HIF)-1α and nuclear factor-kappa B (NF-κB) p65 were immunohistochemically assessed using human coronary atherectomy plaques. Hypoxic areas were localised in the macrophage-rich deep portion of rabbit neointima and positively correlated with the number of nuclei immunopositive for HIF-1α and NF-κB p65, and tissue factor (TF) expression. Immunopositive areas for glycoprotein IIb/IIIa and fibrin in thrombi were significantly correlated with hypoxic areas in arteries. TF and plasminogen activator inhibitor-1 (PAI-1) expression was increased in neointimal tissues and/or macrophages cultured under hypoxia, and both were suppressed by inhibitors of either HIF-1 or NF-κB. In human coronary plaques, the number of HIF-1α-immunopositive nuclei was positively correlated with that of NF-κB-immunopositive nuclei and TF-immunopositive and PAI-1-immunopositive area, and it was significantly higher in thrombotic plaques. Vascular wall hypoxia augments the thrombogenic potential of atherosclerotic plaque and thrombus formation on plaques via prothrombotic factor upregulation.
动脉粥样硬化病变代表一个低氧环境。然而，这种环境在动脉血栓形成中的意义尚未确定。我们旨在评估血管壁缺氧促进动脉血栓形成的假说。我们使用兔模型来检验这一假说，该模型通过 0.5%-胆固醇饮食和重复股动脉球囊损伤来诱导动脉血栓形成。通过盐酸匹莫硝唑（缺氧标志物）免疫组化检测血管壁缺氧。将兔新生内膜和 THP-1 巨噬细胞培养，在 1%O2 的低氧条件下分析促血栓形成因子的表达。使用人冠状动脉粥样斑块来评估缺氧诱导因子（HIF）-1α和核因子-κB（NF-κB）p65的核定位和促血栓形成因子的表达。通过免疫组化评估动脉壁缺氧区与 HIF-1α 和 NF-κB p65 核免疫阳性的数量以及组织因子（TF）表达之间的相关性。血栓中糖蛋白 IIb/IIIa 和纤维蛋白的免疫阳性区域与动脉中的缺氧区域显著相关。在低氧条件下培养的新生内膜组织和/或巨噬细胞中，TF 和纤溶酶原激活物抑制剂-1（PAI-1）的表达增加，并且 HIF-1 或 NF-κB 的抑制剂均可抑制其表达。在人冠状动脉斑块中，HIF-1α 免疫阳性核的数量与 NF-κB 免疫阳性核的数量以及 TF 免疫阳性和 PAI-1 免疫阳性区域的数量呈正相关，在血栓性斑块中明显更高。血管壁缺氧通过促血栓形成因子的上调增加了动脉粥样硬化斑块的血栓形成潜力和斑块上的血栓形成。
