Filipovic Nenad, Rosic Mirko, Tanaskovic Irena, Parodi Oberdan, Fotiadis Dimitris
Faculty of Mechanical Engineering, University of Kragujevac, Sestre Janjica 6, 34000 Kragujevac, Serbia.
Annu Int Conf IEEE Eng Med Biol Soc. 2011;2011:195-8. doi: 10.1109/IEMBS.2011.6090031.
Atherosclerosis develops from oxidized low-density lipoprotein molecules (LDL). When oxidized LDL evolves in plaque formations within an artery wall, a series of reactions occur to repair the damage to the artery wall caused by oxidized LDL. Macrophages accumulate inside arterial intima, they started to collect oxidized LDL and form foam cells. Smooth muscle cells accumulate in the atherosclerotic arterial intima, where they proliferate and secrete extracellular matrix to form a fibrous cap. In this study, experimental model of LDL transport on the isolated blood vessel from rabbit on high fat diet after 8 weeks is simulated numerically by using a specific model and histological data. The 3D blood flow is governed by the Navier-Stokes equations, together with the continuity equation. Mass transfer within the blood lumen and through the arterial wall is coupled with the blood flow by the convection-diffusion equation. LDL transport in lumen of the vessel is described by Kedem-Katchalsky equations. The inflammatory process is solved using three additional reaction-diffusion partial differential equations. Matching of histological rabbit data is performed using 3D histological image reconstruction and 3D deformation of elastic body. Computed concentrations of labeled LDL of 5.2 % and macrophages distribution of 4.2% inside the media are found to be in good agreement with experimental results. This simulation study provides a useful tool for understanding and prediction of LDL transport through the arterial wall and evolution of atherosclerotic plaques.
动脉粥样硬化由氧化的低密度脂蛋白分子（LDL）发展而来。当氧化的LDL在动脉壁内形成斑块时，会发生一系列反应来修复由氧化的LDL对动脉壁造成的损伤。巨噬细胞在动脉内膜内聚集，它们开始收集氧化的LDL并形成泡沫细胞。平滑肌细胞在动脉粥样硬化的动脉内膜中聚集，在那里它们增殖并分泌细胞外基质以形成纤维帽。在本研究中，使用特定模型和组织学数据对高脂饮食8周后兔离体血管上LDL运输的实验模型进行了数值模拟。三维血流由纳维-斯托克斯方程以及连续性方程控制。血流管腔内和穿过动脉壁的传质通过对流扩散方程与血流耦合。血管腔内LDL的运输由 Kedem-Katchalsky 方程描述。炎症过程使用另外三个反应扩散偏微分方程求解。使用三维组织学图像重建和弹性体的三维变形对兔组织学数据进行匹配。发现计算得出的中膜内标记LDL浓度为5.2%，巨噬细胞分布为4.2%，与实验结果吻合良好。该模拟研究为理解和预测LDL通过动脉壁的运输以及动脉粥样硬化斑块的演变提供了一个有用的工具。
