Pavey S N, Cocciolone A J, Marty A Gutierrez, Ismail H N, Hawes J Z, Wagenseil J E
Department of Mechanical Engineering and Materials Science, Washington University in St. Louis, St. Louis, MO.
Exp Mech. 2021 Jan;61(1):41-51. doi: 10.1007/s11340-020-00625-1. Epub 2020 Jul 15.
Elastic fibers are composed primarily of the protein elastin and they provide reversible elasticity to the large arteries. Degradation of elastic fibers is a common histopathology in aortic aneurysms. Pentagalloyl glucose (PGG) has been shown to bind elastin and stabilize elastic fibers in some in vitro studies and in vivo models of abdominal aortic aneurysms, however its effects on native arteries are not well described.
Perform detailed studies of the biomechanical effects of PGG on native arteries and the preventative capabilities of PGG for elastin degraded arteries.
We treated mouse carotid arteries with PGG, elastase (ELA), and PGG+ELA and compared the wall structure, solid mechanics, and fluid transport properties to untreated (UNT) arteries.
We found that PGG alone decreased compliance compared to UNT arteries, but did not affect any other structural or biomechanical measures. Mild (30 sec) ELA treatment caused collapse and fragmentation of the elastic lamellae, plastic deformation, decreased compliance, increased modulus, and increased hydraulic conductance of the arterial wall compared to UNT. PGG+ELA treatment partially protected from all of these changes, in particular the plastic deformation. PGG mechanical protection varied considerably across PGG+ELA samples and appeared to correlate with the structural changes.
Our results provide important considerations for the effects of PGG on native arteries and a baseline for further biomechanical studies on preventative elastic fiber stabilization.
弹性纤维主要由弹性蛋白组成，为大动脉提供可逆弹性。弹性纤维降解是主动脉瘤常见的组织病理学特征。在一些体外研究以及腹主动脉瘤的体内模型中，没食子五倍子酸葡萄糖（PGG）已被证明可结合弹性蛋白并稳定弹性纤维，然而其对天然动脉的影响尚无详尽描述。
详细研究PGG对天然动脉的生物力学作用以及PGG对弹性蛋白降解动脉的预防能力。
我们用PGG、弹性蛋白酶（ELA）和PGG + ELA处理小鼠颈动脉，并将其壁结构、固体力学和流体传输特性与未处理（UNT）的动脉进行比较。
我们发现，与UNT动脉相比，单独使用PGG会降低顺应性，但不影响任何其他结构或生物力学指标。与UNT相比，轻度（30秒）ELA处理导致弹性板层塌陷和破碎、塑性变形、顺应性降低、模量增加以及动脉壁水力传导率增加。PGG + ELA处理可部分防止所有这些变化，尤其是塑性变形。PGG的机械保护作用在PGG + ELA样本中差异很大，并且似乎与结构变化相关。
我们的结果为PGG对天然动脉的影响提供了重要参考，并为进一步进行预防性弹性纤维稳定的生物力学研究提供了基线。
