School of Biomedical Engineering, International University, Quarter 6, Linh Trung, Thu Duc District, Ho Chi Minh City, Vietnam.
Vietnam National University, Linh Trung, Thu Duc District, Ho Chi Minh City, Vietnam.
Phys Biol. 2024 Oct 18;21(6). doi: 10.1088/1478-3975/ad838c.
Wall shear stress (WSS) is a critical factor in vascular biology, and both high and low WSS are implicated in atherosclerosis. Fibronectin (FN) is a key extracellular matrix protein that plays an important role in cell activities. Under high shear stress, plasma FN undergoes fibrillogenesis; however, its behavior under low shear stress remains unclear. This study aimed to investigate the formation ofcell-free fibrillar FN (FFN) under low shear rate conditions and its effect on bovine aortic endothelial cell behavior. FN (500g ml) was perfused through slide chambers at three flow rates (0.16 ml h, 0.25 ml h, and 0.48 ml h), corresponding to low shear rates of 0.35 s, 0.55 s, and 1.05 s, respectively, for 4 h at room temperature. The formed FN matrices were observed using fluorescence microscopy and scanning electron microscopy. Under low shear rates, distinct FN matrix structures were observed. FFN0.48 formed immense fibrils with smooth surfaces, FFN0.25 formed a matrix with a rough surface, and FFN16 exhibited nodular structures. FFN0.25 supported cell activities to a greater extent than native FN and other FFN surfaces. Our study suggests that abnormally low shear conditions impact FN structure and function and enhance the understanding of FN fibrillogenesis in vascular biology, particularly in atherosclerosis.
壁面切应力（WSS）是血管生物学的一个关键因素，高壁面切应力和低壁面切应力都与动脉粥样硬化有关。纤维连接蛋白（FN）是一种关键的细胞外基质蛋白，在细胞活动中发挥着重要作用。在高壁面切应力下，血浆 FN 发生纤维原纤维形成；然而，其在低壁面切应力下的行为仍不清楚。本研究旨在探讨低剪切速率条件下无细胞纤维状 FN（FFN）的形成及其对牛主动脉内皮细胞行为的影响。FN（500g ml）在三个流速（0.16 ml h、0.25 ml h 和 0.48 ml h）下通过滑动室灌注，分别对应于低剪切速率 0.35 s、0.55 s 和 1.05 s，在室温下持续灌注 4 小时。使用荧光显微镜和扫描电子显微镜观察形成的 FN 基质。在低剪切速率下，观察到明显的 FN 基质结构。FFN0.48 形成了巨大的纤维，表面光滑，FFN0.25 形成了表面粗糙的基质，FFN16 则呈现出结节状结构。FFN0.25 比天然 FN 和其他 FFN 表面更能支持细胞活性。本研究表明，异常低的剪切条件会影响 FN 的结构和功能，并深入了解血管生物学中 FN 的纤维原纤维形成，特别是在动脉粥样硬化中。
