Carbamylated Low-Density Lipoproteins Induce a Prothrombotic State Via LOX-1 Impact on Arterial Thrombus Formation In Vivo
Carbamylated Low-Density Lipoproteins Induce a Prothrombotic State Via LOX-1 Impact on Arterial Thrombus Formation In Vivo
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DOI：
10.1016/j.jacc.2016.07.755
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发表时间：
2016-10-11
影响因子：
24
通讯作者：
Tanner, Felix C.
中科院分区：
文献类型：
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作者：
Holy, Erik W.;Akhmedov, Alexander;Tanner, Felix C.
背景氨甲酰化可改变低密度脂蛋白(LDL)的结构，促进慢性肾脏病(CKD)患者的血管炎症和功能障碍。目的本研究旨在确定氨甲酰化的低密度脂蛋白(CLDL)是否在血管细胞和血小板上发挥血栓形成作用，以及cLDL是否促进活体动脉血栓的形成。用氰酸钾诱导健康人低密度脂蛋白的体外氨甲基化反应。在小鼠颈动脉光化学损伤模型中分析了动脉血栓的形成。用Western blotting、流式细胞仪和实时定量聚合酶链式反应(Real-time PCR)分析蛋白表达和mRNA水平。结果与天然低密度脂蛋白(NLDL)或赋形剂相比，静脉注射cLDL可加速小鼠动脉血栓的形成。小鼠颈动脉组织裂解产物显示，cLDL可诱导血管细胞表达TF、PAI-1和LOX-1mRNA。在人主动脉平滑肌和血管内皮细胞中，cLDL可诱导TF和PAI-1的表达。相反，nLDL对这两种细胞类型都没有影响。NLDL和cLDL对静息状态下的血小板无聚集作用，而cLDL可促进不同激动剂对血小板的聚集。这一作用是通过丝裂原活化蛋白激酶p38的磷酸化和LOX-1转位到细胞表面来实现的。从CKD患者体内分离的低密度脂蛋白模拟了cLDL对血管细胞、血小板和体内血栓形成的促血栓形成作用。结论cLDL通过激活LOX-1受体在血管细胞和血小板中诱导血栓形成，并促进体内血栓的形成。这一观察揭示了CKD患者急性血栓事件发生率增加的新机制，并可能导致在这一人群中开发新的脂靶向疗法。(J am Coll心脏ol 2016；68：1664-76)(C)2016，由美国心脏病学会基金会主办。
BACKGROUND Carbamylation alters low-density lipoprotein (LDL) structure and is thought to promote vascular inflammation and dysfunction in patients with chronic kidney disease (CKD).OBJECTIVES This study sought to determine whether carbamylated LDL (cLDL) exerts prothrombotic effects in vascular cells and platelets and whether cLDL enhances arterial thrombus formation in vivo.METHODS LDL was isolated from healthy subjects or patients with CKD by sequential ultracentrifugation. Ex vivo carbamylation of LDL from healthy subjects was induced with potassium cyanate. Arterial thrombus formation was analyzed in a murine carotid artery photochemical injury model. Protein expression and mRNA levels were analyzed by Western blotting, flow cytometry, and real-time PCR. Platelet aggregation was measured by impedance aggregometry.RESULTS Intravenous administration of cLDL in mice accelerated arterial thrombus formation compared to treatment with native LDL (nLDL) or vehicle. Tissue lysates of mouse carotid arteries revealed that cLDL induced the expression of TF, PAI-1, and LOX-1 mRNA in vascular cells. In human aortic smooth muscle and endothelial cells, cLDL induced TF and PAI-1 expression. In contrast, nLDL had no effect on either cell type. While nLDL and cLDL had no aggregatory effect on resting platelets, cLDL enhanced platelet aggregation in response to different agonists. This effect was mediated by mitogen-activated protein kinase p38 phosphorylation and LOX-1 translocation to the surface. LDL isolated from patients with CKD mimicked the prothrombotic effects of cLDL on vascular cells, platelets, and thrombus formation in vivo.CONCLUSIONS We found that cLDL induces prothrombotic effects in vascular cells and platelets by activation of the LOX-1 receptor and enhances thrombus formation in vivo. This observation reveals a new mechanism underlying the increased incidence of acute thrombotic events observed in patients with CKD and may lead to the development of new lipid-targeting therapies in this population. (J Am Coll Cardiol 2016; 68: 1664-76) (C) 2016 by the American College of Cardiology Foundation.