Collagen telopeptides (cross-linking sites) play a role in collagen gel lattice contraction.
Collagen telopeptides (cross-linking sites) play a role in collagen gel lattice contraction.
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DOI：
10.1111/1523-1747.ep12481920
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发表时间：
1991-09
期刊：
影响因子：
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通讯作者：
D. Woodley;M. Yamauchi;K. Wynn;G. Mechanic;R. A. Briggaman
中科院分区：
文献类型：
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作者：
D. Woodley;M. Yamauchi;K. Wynn;G. Mechanic;R. A. Briggaman
溶解的间质胶原在生理条件下将形成纤维状凝胶样晶格。在存在人真皮成纤维细胞的情况下，胶原晶格将收缩。收缩率可以通过计算机辅助平面测量来确定。涉及收缩的机制尚不清楚。使用该系统，发现当用缺乏端肽的胶原蛋白代替天然胶原蛋白时，收缩速率显著降低。组氨酸羟赖氨酸正亮氨酸（HHL）是成熟皮肤中主要的稳定的三功能胶原交联，其涉及羧基末端端肽位点16 c，即I型胶原中α 1（I）的端肽区域的羧基末端的第16个氨基酸残基。很少，如果有的话，HHL存在于天然的，纯化的，重建的，可溶性胶原纤维从1%乙酸提取的2岁的牛皮。相比之下，HHL交联存在于由成纤维细胞收缩的相同胶原的晶格中（每摩尔胶原0.22摩尔交联）。然而，大鼠尾腱不包含HHL交联，并且由大鼠尾腱胶原制成的胶原晶格能够收缩。这表明端肽位点，而不是成熟的HHL交联本身，是成纤维细胞收缩胶原晶格所必需的。β-氨基丙腈富马酸盐（BAPN）是一种通过抑制赖氨酰氧化酶来干扰胶原交联的强效lathyrogen，也抑制了由天然胶原组成的晶格中的晶格细胞收缩速率。然而，抑制胶原晶格收缩所必需的BAPN浓度也抑制成纤维细胞生长，提示细胞毒性。与其他研究一致，我们发现当使用去除纤连蛋白的血清时，晶格收缩率没有抑制。收缩凝胶的电子显微镜显示典型的胶原纤维具有特征性的轴向周期性。这些数据提供了胶原蛋白端肽位点在胶原蛋白凝胶晶格收缩中起作用的证据。
Solubilized interstitial collagens will form a fibrillar, gel-like lattice when brought to physiologic conditions. In the presence of human dermal fibroblasts the collagen lattice will contract. The rate of contraction can be determined by computer-assisted planemetry. The mechanisms involved in contraction are as yet unknown. Using this system it was found that the rate of contraction was markedly decreased when collagen lacking telopeptides was substituted for native collagen. Histidinohydroxylysinonorleucine (HHL) is a major stable trifunctional collagen cross-link in mature skin that involves a carboxyl terminal, telopeptide site 16c, the sixteenth amino acid residue from the carboxy terminal of the telopeptide region of alpha 1 (I) in type I collagen. Little, if any, HHL was present in native, purified, reconstituted, soluble collagen fibrils from 1% acetic acid-extracted 2-year-old bovine skin. In contrast, HHL cross-links were present (0.22 moles of cross-link per mole of collagen) in lattices of the same collagen contracted by fibroblasts. However, rat tail tendon does not contain HHL cross-links, and collagen lattices made of rat tail tendon collagen are capable of contraction. This suggests that telopeptide sites, and not mature HHL cross-links per se, are essential for fibroblasts to contract collagen lattices. Beta-aminopropionitrile fumarate (BAPN), a potent lathyrogen that perturbs collagen cross-linking by inhibition of lysyl oxidase, also inhibited the rate of lattice cell contraction in lattices composed of native collagen. However, the concentrations of BAPN that were necessary to inhibit the contraction of collagen lattices also inhibited fibroblast growth suggestive of cellular toxicity. In accordance with other studies, we found no inhibition of the rate of lattice contraction when fibronectin-depleted serum was used. Electron microscopy of contracted gels revealed typical collagen fibers with a characteristic axial periodicity. The data provide evidence that collagen telopeptide sites play a role in collagen gel lattice contraction.