短暂的低剪压预条件影响长期内皮引力和在高剪流下对齐
Mohanish K Chandurkar1,2, Nikhil Mittal1,2, Shaina P Royer-Weeden1,2
1Department of Biomedical Engineering, Michigan Technological University, Houghton, Michigan, United States.
概括
初始低流体剪切应力 (FSS) 启动内皮细胞 (ECs) 进行细胞引和对齐的持久变化,即使在高FSS下. 这种预先条件显著影响了在动态血管环境中的EC行为.
科学领域:
- 血管生物学 血管生物学
- 细胞生物力学 细胞生物力学
- 生物物理学的生物物理.
背景情况:
- 内皮细胞 (ECs) 响应流体剪切应激 (FSS),这是血管健康的关键因素.
- 高层FSS通常是有益的,而低层或扰乱的FSS会导致内皮功能障碍和炎症.
- 对于ECs对动态FSS变化的适应机制尚未完全理解.
研究的目的:
- 为了研究内皮细胞如何在从低流体剪切应力过渡到高流体剪切应力的过程中适应其引力.
- 阐明初始剪切应力暴露对内皮细胞行为和对齐的长期影响.
- 了解剪切应激史对内皮细胞反应的影响.
主要方法:
- 利用引力显微镜与定制流体室相结合,分析人类脉内皮细胞.
- 在低流体剪切应力条件和高流体剪切应力条件之间应用受控过渡.
- 采用格兰杰因果关系分析来确定引向量的方向和细胞对齐之间的功能关系.
主要成果:
- 最初的低FSS暴露导致了延迟但实质性的EC引的增加,随后的高FSS.
- 直接高FSS导致了快速的引激增,随后明显下降到基线以下.
- 发现EC引向量的方向取决于最初的剪切应力暴露,影响后续的细胞对齐.
结论:
- 短期暴露于低FSS对内皮细胞的引和方向有持久的影响.
- 剪切应激暴露的历史极大地决定了内皮细胞的适应反应和对齐.
- 在对不同剪切应力模式的反应中,内皮细胞引方向和细胞方向之间存在功能联系.
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