Atomic Force Microscopy-Based Measurements of Retinal Microvessel Stiffness in Mice with Endothelial-Specific Deletion of CCN1.
Atomic Force Microscopy-Based Measurements of Retinal Microvessel Stiffness in Mice with Endothelial-Specific Deletion of CCN1.
复制标题
基于原子力显微镜测量 CCN1 内皮特异性缺失的小鼠视网膜微血管硬度。
DOI：
10.1007/978-1-0716-2744-0_22
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发表时间：
2023
期刊：
影响因子：
--
通讯作者：
Melendez-Vasquez,CarmenV
中科院分区：
文献类型：
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作者：
Chaqour,Brahim;Grant,MariaB;Lau,LesterF;Wang,Biran;Urbanski,MateuszM;Melendez-Vasquez,CarmenV
血管僵硬是人类血管疾病的独立预测因子，与缺血、糖尿病、高血压、高脂血症和/或衰老有关。血管硬化增加是由于微尺度结构和/或细胞外、细胞骨架和核基质蛋白含量的变化。这些改变虽然在大血管中最为明显，但也逐渐发生在微血管中，并在包括糖尿病视网膜病变在内的许多微血管病变的发生和发展中发挥重要作用。虽然通过脉搏波速测量动脉刚度的宏观测量常用于临床诊断，但完整微血管的刚度变化及其原因尚未表征。在这里，我们描述了使用原子力显微镜（AFM）来确定小鼠视网膜毛细血管的刚度，并评估其由细胞通信网络（CCN） 1调节，这是一种刚度敏感基因编码的基质细胞蛋白。AFM产生可重复的测量视网膜毛细血管刚度在轻固定新鲜分离视网膜平支架。AFM测量还显示，内皮特异性缺失CCN1的小鼠视网膜微血管的顺应性特性发生了显著变化，这表明CCN1的表达或缺乏会影响体内微血管细胞的力学特性。因此，AFM具有原位测量视网膜毛细血管局部模量所需的力灵敏度和空间分辨率，并最终研究微血管顺应性异质性作为疾病发病机制的关键组成部分。
Vascular stiffness is an independent predictor of human vascular diseases and is linked to ischemia, diabetes, high blood pressure, hyperlipidemia, and/or aging. Blood vessel stiffening increases owing to changes in the microscale architecture and/or content of extracellular, cytoskeletal, and nuclear matrix proteins. These alterations, while best appreciated in large blood vessels, also gradually occur in the microvasculature and play an important role in the initiation and progression of numerous microangiopathies including diabetic retinopathy. Although macroscopic measurements of arterial stiffness by pulse wave velocity are often used for clinical diagnosis, stiffness changes of intact microvessels and their causative factors have not been characterized. Herein, we describe the use of atomic force microscopy (AFM) to determine stiffness of mouse retinal capillaries and assess its regulation by the cellular communication network (CCN) 1, a stiffness-sensitive gene-encoded matricellular protein. AFM yields reproducible measurements of retinal capillary stiffness in lightly fixed freshly isolated retinal flat mounts. AFM measurements also show significant changes in compliance properties of the retinal microvasculature of mice with endothelial-specific deletion of CCN1, indicating that CCN1 expression, or lack thereof, affects the mechanical properties of microvascular cells in vivo. Thus, AFM has the force sensitivity and the spatial resolution necessary to measure the local modulus of retinal capillaries in situ and eventually to investigate microvascular compliance heterogeneities as key components of disease pathogenesis.