Effects of shear stress on low-density lipoproteins (LDL) transport in the multi-layered arteries

AbstractThe purpose of this study is to compare the effect of the different physical factors on low-density lipoproteins (LDL) accumulation from flowing blood to the arterial wall of the left coronary arteries. The three-dimensional (3D) computational model of the left coronary arterial tree is reconstructed from a patient-specific computed tomography angiography (CTA) image. The endothelium of the coronary artery is represented by a shear stress dependent three-pore model. Fluid–structure interaction ($$FSI$$ FSI ) based numerical method is used to study the LDL transport from vascular lumen into the arterial wall. The results show that the high elastic property of the arterial wall decreases the complexity of the local flow field in the coronary bifurcation system. The places of high levels of LDL uptake coincide with the regions of low wall shear stress. In addition, hypertension promotes LDL uptake from flowing blood in the arterial wall, while the thickened arterial wall decreases this process. The present computer strategy combining the methods of coronary CTA image 3D reconstruction, $$FSI$$ FSI simulation, and three-pore modeling was illustrated to be effective on the simulation of the distribution and the uptake of LDL. This may have great potential for the early prediction of the local atherosclerosis lesion in the human left coronary artery.

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Influence of a laminar steady-state fluid-imposed wall shear stress on the binding, internalization, and degradation of low-density lipoproteins by cultured arterial endothelium.

Circulation ◽

10.1161/01.cir.76.3.648 ◽

1987 ◽

Vol 76 (3) ◽

pp. 648-656 ◽

Cited By ~ 119

Author(s):

E A Sprague ◽

B L Steinbach ◽

R M Nerem ◽

C J Schwartz

Keyword(s):

Shear Stress ◽

Steady State ◽

Wall Shear Stress ◽

Low Density Lipoproteins ◽

Low Density ◽

Wall Shear ◽

Arterial Endothelium

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Effect of Fluid Shear Stress on Endocytosis of Heparan Sulfate and Low-density Lipoproteins

Journal of Biomedicine and Biotechnology ◽

10.1155/2007/65136 ◽

2007 ◽

Vol 2007 ◽

pp. 1-8 ◽

Cited By ~ 8

Author(s):

Irmeli Barkefors ◽

Cyrus K. Aidun ◽

E. M. Ulrika Egertsdotter

Keyword(s):

Shear Stress ◽

Heparan Sulfate ◽

Fluid Shear Stress ◽

Critical Factor ◽

Low Density Lipoproteins ◽

Confocal Imaging ◽

Low Density ◽

Fluid Shear ◽

Main Component ◽

Static Conditions

Hemodynamic stress is a critical factor in the onset of atherosclerosis such that reduced rates of shear stress occurring at regions of high curvature are more prone to disease. The level of shear stress has direct influence on the thickness and integrity of the glycocalyx layer. Here we show that heparan sulfate, the main component of the glycocalyx layer, forms an intact layer only on cell surfaces subjected to shear, and not under static conditions. Furthermore, receptor-mediated endocytosis of heparan sulfate and low-density liporoteins is not detectable in cells exposed to shear stress. The internalized heparan sulfate and low-density lipoproteins are colocalized as shown by confocal imaging.

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Numerical simulation of haemodynamics and low-density lipoprotein transport in the rabbit aorta and their correlation with atherosclerotic plaque thickness

Journal of The Royal Society Interface ◽

10.1098/rsif.2017.0140 ◽

2017 ◽

Vol 14 (129) ◽

pp. 20170140 ◽

Cited By ~ 6

Author(s):

Xiaoyin Li ◽

Xiao Liu ◽

Peng Zhang ◽

Chenglong Feng ◽

Anqiang Sun ◽

...

Keyword(s):

Blood Flow ◽

Shear Stress ◽

Atherosclerotic Plaque ◽

Low Density Lipoprotein ◽

Density Lipoprotein ◽

Rabbit Aorta ◽

Low Density ◽

Ldl Transport ◽

Clear Cut ◽

Point Correlation

Two mechanisms of shear stress and mass transport have been recognized to play an important role in the development of localized atherosclerosis. However, their relationship and roles in atherogenesis are still obscure. It is necessary to investigate quantitatively the correlation among low-density lipoproteins (LDL) transport, haemodynamic parameters and plaque thickness. We simulated blood flow and LDL transport in rabbit aorta using computational fluid dynamics and evaluated plaque thickness in the aorta of a high-fat-diet rabbit. The numerical results show that regions with high luminal LDL concentration tend to have severely negative haemodynamic environments (HEs). However, for regions with moderately and slightly high luminal LDL concentration, the relationship between LDL concentration and the above haemodynamic indicators is not clear cut. Point-by-point correlation with experimental results indicates that severe atherosclerotic plaque corresponds to high LDL concentration and seriously negative HEs, less severe atherosclerotic plaque is related to either moderately high LDL concentration or moderately negative HEs, and there is almost no atherosclerotic plaque in regions with both low LDL concentration and positive HEs. In conclusion, LDL distribution is closely linked to blood flow transport, and the synergetic effects of luminal surface LDL concentration and wall shear stress-based haemodynamic indicators may determine plaque thickness.

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