Age-dependent changes in the structure, composition and biophysical properties of a human basement membrane
Age-dependent changes in the structure, composition and biophysical properties of a human basement membrane
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DOI：
10.1016/j.matbio.2010.03.004
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发表时间：
2010-06-01
期刊：
影响因子：
6.9
通讯作者：
Halfter, Willi
中科院分区：
文献类型：
--
作者：
Candiello, Joseph;Cole, Gregory J.;Halfter, Willi
基底膜（BMs）被认为是均匀的、约100纳米厚的细胞外基质薄片，作为上皮细胞、内皮细胞和肌管的基底。为了查明基底膜在整个生命过程中是否保持其超微结构、蛋白质组成和生物物理特性，对人内界膜（ILM）的自然老化过程进行了研究。内界膜是视网膜玻璃体表面的一种基底膜，它将视网膜与玻璃体连接起来。透射电子显微镜（TEM）显示，内界膜的厚度从胎儿期的70纳米稳定增加到90岁时的几微米。到20岁时，内界膜失去其层状结构，变成无定形且非常不规则的细胞外基质层。原子力显微镜（AFM）显示，天然的、水合的内界膜平均比透射电子显微镜下看到的脱水内界膜厚4倍，并且其厚度主要由其结合水的蛋白聚糖决定。形态变化伴随着生化组成的年龄相关变化，其中Ⅳ型胶原蛋白和聚集蛋白聚糖的相对浓度随年龄增加，而层粘连蛋白的浓度随年龄降低。原子力显微镜的力 - 压痕测量还显示，随着年龄的增长，内界膜变得越来越硬。数据表明，来自人体其他组织的基底膜可能会经历类似的年龄相关变化。（C）2010爱思唯尔有限公司。保留所有权利。
Basement membranes (BMs) are considered to be uniform, approximately 100 nm-thin extracellular matrix sheets that serve as a substrate for epithelial cells, endothelial cells and myotubes. To find out whether BMs maintain their ultrastructure, protein composition and biophysical properties throughout life the natural aging history of the human inner limiting membranes (ILM) was investigated. The ILM is a BM at the vitreal surface of the retina that connects the retina with the vitreous. Transmission electron microscopy (TEM) showed that the ILM steadily increases in thickness from 70 nm at fetal stages to several microns at age 90. By the age of 20, the ILM loses its laminated structure to become an amorphous and very irregular extracellular matrix layer. Atomic force microscopy (AFM) showed that the native, hydrated ILMs are on average 4-fold thicker than the dehydrated ILMs as seen by TEM and that their thickness is prominently determined by its water-binding proteoglycans. The morphological changes are accompanied by age-related changes in the biochemical composition, whereby the relative concentrations of collagen IV and agrin increase, and the concentration of laminin decreases with age. Force-indentation measurements by AFM also showed that ILMs become increasingly stiffer with advancing age. The data suggest that BMs from other human tissues may undergo similar age-related changes. (C) 2010 Elsevier B.V. All rights reserved.