Moonen Rik P M, Coolen Bram F, Sluimer Judith C, Daemen Mat J A P, Strijkers Gustav J
Department of Radiology and Nuclear Medicine, Maastricht University Medical Center, 6229 ER Maastricht, The Netherlands.
CARIM School for Cardiovascular Diseases, Maastricht University Medical Center, 6229 ER Maastricht, The Netherlands.
Pharmaceutics. 2021 Feb 19;13(2):279. doi: 10.3390/pharmaceutics13020279.
The purpose of our study was to monitor the iron oxide contrast agent uptake in mouse brachiocephalic artery (BCA) atherosclerotic plaques in vivo by quantitative T-mapping magnetic resonance imaging (MRI). Female ApoE mice ( = 32) on a 15-week Western-type diet developed advanced plaques in the BCA and were injected with ultra-small superparamagnetic iron oxides (USPIOs). Quantitative in vivo MRI at 9.4 T was performed with a Malcolm-Levitt (MLEV) prepared T-mapping sequence to monitor the nanoparticle uptake in the atherosclerotic plaque. Ex vivo histology and particle electron paramagnetic resonance (pEPR) were used for validation. Longitudinal high-resolution in vivo T-value maps were acquired with consistent quality. Average T values in the plaque decreased from a baseline value of 34.5 ± 0.6 ms to 24.0 ± 0.4 ms one day after injection and partially recovered to an average T of 27 ± 0.5 ms after two days. T values were inversely related to iron levels in the plaque as determined by ex vivo particle electron paramagnetic resonance (pEPR). We concluded that MRI T mapping facilitates a robust quantitative readout for USPIO uptake in atherosclerotic plaques in arteries near the mouse heart.
我们研究的目的是通过定量T映射磁共振成像（MRI）在体内监测小鼠臂头动脉（BCA）动脉粥样硬化斑块中氧化铁造影剂的摄取情况。15周西式饮食喂养的雌性载脂蛋白E基因敲除小鼠（n = 32）在BCA中形成了晚期斑块，并注射了超小超顺磁性氧化铁（USPIO）。采用Malcolm-Levitt（MLEV）准备的T映射序列在9.4 T下进行定量体内MRI，以监测纳米颗粒在动脉粥样硬化斑块中的摄取情况。离体组织学和颗粒电子顺磁共振（pEPR）用于验证。以一致的质量获取纵向高分辨率体内T值图。注射后一天，斑块中的平均T值从基线值34.5±0.6 ms降至24.0±0.4 ms，两天后部分恢复至平均T值27±0.5 ms。如通过离体颗粒电子顺磁共振（pEPR）所确定的，T值与斑块中的铁含量呈负相关。我们得出结论，MRI T映射有助于对小鼠心脏附近动脉粥样硬化斑块中USPIO的摄取进行可靠的定量读出。
