Free DNA precipitates calcium phosphate apatite crystals in the arterial wall in vivo
Free DNA precipitates calcium phosphate apatite crystals in the arterial wall in vivo
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DOI：
10.1016/j.atherosclerosis.2017.03.005
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发表时间：
2017-04-01
期刊：
影响因子：
5.3
通讯作者：
Michel, Jean-Baptiste
中科院分区：
文献类型：
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作者：
Coscas, Raphael;Bensussan, Marie;Michel, Jean-Baptiste
背景和目的：动脉壁钙评分和循环游离DNA水平目前在临床实践中被用作心血管风险的生物标志物。磷酸钙磷灰石在动脉壁上的保留需要在阴离子平台上沉淀。在这里，我们探索无组织DNA作为这样一个平台的作用。方法：第一步对人和大鼠钙化动脉标本进行组织学观察。采用多种染色法（茜素红、荧光赫斯特、DNA免疫染色和TUNEL法）评价游离DNA与钙化组织的共定位。切片经EDTA处理以显示钙化背景。其次，建立主动脉内灌注游离DNA和弹性酶+游离DNA诱导的大鼠血管钙化模型。3周时对大鼠主动脉进行微ct计算钙评分。采用傅里叶变换红外光谱（mu FTIR）和场发射扫描电镜（FE-SEM）对大鼠和人的钙化进行定性表征。结果：我们的组织学研究显示动脉钙化斑块与游离DNA共定位。在主动脉内灌注模型中，游离DNA能够穿透动脉壁并诱导钙化，而在对照主动脉中未见显微镜下的钙化。弹性蛋白酶+游离DNA组的钙化评分显著高于对照组。定性评价显示，人和大鼠动脉标本中存在典型的磷酸钙潴留。结论：这项转化研究表明，游离DNA可能通过在血管壁沉淀磷酸钙磷灰石晶体参与动脉钙化的形成。(c) 2017 Elsevier B.V.版权所有
Background and aims: The arterial wall calcium score and circulating free DNA levels are now used in clinical practice as biomarkers of cardiovascular risk. Calcium phosphate apatite retention in the arterial wall necessitates precipitation on an anionic platform. Here, we explore the role of tissue-free DNA as such a platform.Methods: The first step consisted of histological observation of samples from human and rat calcified arteries. Various stains were used to evaluate colocalization of free DNAwith calcified tissue (alizarin red, fluorescent Hoechst, DNA immunostaining and TUNEL assay). Sections were treated by EDTA to reveal calcification background. Secondly, a rat model of vascular calcifications induced by intra-aortic infusions of free DNA and elastase + free DNA was developed. Rat aortas underwent a micro-CT for calcium score calculation at 3 weeks. Rat and human calcifications were qualitatively characterized using mFourier Transform Infrared Spectroscopy (mu FTIR) and Field Emission-Scanning Electron Microscopy (FE-SEM).Results: Our histological study shows colocalization of calcified arterial plaques with free DNA. In the intraaortic infusion model, free DNA was able to penetrate into the arterial wall and induce calcifications whereas no microscopic calcificationwas seen in control aortas. The calcification score in the elastase + free DNA group was significantly higher than in the control groups. Qualitative evaluation with mu FTIR and FESEM demonstrated typical calcium phosphate retention in human and rat arterial specimens.Conclusions: This translational study demonstrates that free DNA could be involved in arterial calcification formation by precipitating calcium phosphate apatite crystals in the vessel wall. (c) 2017 Elsevier B.V. All rights reserved.