Dhar Srijita, Sun Zhe, Meininger Gerald A, Hill Michael A
Dalton Cardiovascular Research Center, University of Missouri, Columbia, MO, USA.
Department of Medical Pharmacology and Physiology, University of Missouri, Columbia, MO, USA.
Microcirculation. 2017 Apr;24(3). doi: 10.1111/micc.12347.
We aimed to investigate whether advanced nonenzymatic glycation of the ECM protein, fibronectin, impacts its normal integrin-mediated interaction with arteriolar VSMC.
AFM was performed on cultured VSMC from rat cremaster arterioles to study native and glycated fibronectin (FN and gFN) interactions with cellular integrins. AFM probes were functionalized with FN or gFN or with native or glycated albumin (gAlb) as controls.
VSMC showed increased adhesion probability to gFN (72.9±3.5%) compared with native FN (63.0±1.6%). VSMC similarly showed increased probability of adhesion (63.8±1.7%) to gAlb compared with native Alb (40.1±4.7%). Adhesion of native FN to VSMC was α5 and β1 integrin dependent whereas adhesion of gFN to VSMC was integrin independent. The RAGE-selective inhibitor, FPS-ZM1, blocked gFN (and gAlb) adhesion, suggesting that adhesion of glycated proteins was RAGE dependent. Interaction of FN with VSMC was not altered by soluble gFN while soluble native FN did not inhibit adhesion of gFN to VSMC. In contrast, gAlb inhibited adhesion of gFN to VSMC in a concentration-dependent manner.
Glycation of FN shifts the nature of cellular adhesion from integrin- to RAGE-dependent mechanisms.
我们旨在研究细胞外基质蛋白纤连蛋白的晚期非酶糖基化是否会影响其与小动脉血管平滑肌细胞正常的整合素介导的相互作用。
对来自大鼠提睾肌小动脉的培养血管平滑肌细胞进行原子力显微镜检测，以研究天然和糖基化纤连蛋白（FN和gFN）与细胞整合素的相互作用。用FN或gFN或用天然或糖基化白蛋白（gAlb）作为对照对原子力显微镜探针进行功能化处理。
与天然FN（63.0±1.6%）相比，血管平滑肌细胞对gFN的黏附概率增加（72.9±3.5%）。与天然白蛋白（40.1±4.7%）相比，血管平滑肌细胞对gAlb的黏附概率同样增加（63.8±1.7%）。天然FN与血管平滑肌细胞的黏附依赖于α5和β1整合素，而gFN与血管平滑肌细胞的黏附不依赖于整合素。RAGE选择性抑制剂FPS-ZM1可阻断gFN（和gAlb）的黏附，提示糖基化蛋白的黏附依赖于RAGE。可溶性gFN不改变FN与血管平滑肌细胞的相互作用，而可溶性天然FN不抑制gFN与血管平滑肌细胞的黏附。相反，gAlb以浓度依赖的方式抑制gFN与血管平滑肌细胞的黏附。
FN的糖基化将细胞黏附的性质从整合素依赖性机制转变为RAGE依赖性机制。
