Effects of aging and caloric restriction on extracellular matrix biosynthesis in a model of injury repair in rats.
Effects of aging and caloric restriction on extracellular matrix biosynthesis in a model of injury repair in rats.
复制标题
衰老和热量限制对大鼠损伤修复模型中细胞外基质生物合成的影响。
DOI：
10.1093/gerona/50a.1.b40
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发表时间：
1995
期刊：
影响因子：
--
通讯作者：
McDonald,R
中科院分区：
文献类型：
--
作者：
Reiser,K;McGee,C;Rucker,R;McDonald,R
本研究旨在研究衰老和热量限制对伤口愈合模型中胶原蛋白沉积的影响。将聚乙烯醇海绵植入 6、10 或 24 个月大的 Fischer 344 只大鼠体内。 7、10 或 14 天后取出海绵并分析羟脯氨酸含量和酶交联。衰老与胶原蛋白积累的减少以及胶原蛋白积累达到峰值速率的延迟有关。相对于年轻动物，年老动物的肉芽组织中酶交联水平增加。仅在两周的实验期间维持热量限制（随意摄入的60%）不会影响胶原蛋白的积累，但确实导致植入10天而非14天的海绵中双功能交联二羟基赖氨酸正亮氨酸（DHLNL）水平下降。在海绵植入前 4 个月开始限制热量，导致所有植入时间的胶原蛋白积累减少和 DHLNL 减少。这些研究表明：（1）衰老会影响胶原蛋白的总生成量以及响应损伤时的胶原蛋白生成率； (2) 衰老与肉芽组织交联受损无关； (3) 长期热量限制与胶原蛋白生成减少和 DHLNL 水平降低有关； (4)长期热量限制对伤口愈合的不利影响可能对老年动物的伤口愈合影响更大。
This study was designed to investigate the effects of aging and caloric restriction on collagen deposition in a model of wound healing. Polyvinyl alcohol sponges were implanted in Fischer 344 rats aged 6,10, or 24 months. Sponges were removed after 7, 10, or 14 days and analyzed for hydroxyproline content and for enzymatic crosslinks. Aging was associated with a decrease in collagen accumulation as well as a delay in reaching peak rates of collagen accumulation. Levels of enzymatic crosslinks were increased in granulation tissue from old animals relative to young animals. Caloric restriction (60% of ad libitum intake) maintained only during the 2-week experimental period did not affect collagen accumulation, but did result in decreased levels of the difunctional crosslink dihydroxylysinonorleucine (DHLNL) in sponges implanted for 10 days, but not 14 days. Caloric restriction initiated 4 months before sponges were implanted resulted in decreased collagen accumulation and decreases in DHLNL at all implantation times. These studies suggest that: (1) aging affects total collagen production as well as rate of collagen production in response to injury; (2) aging is not associated with impaired crosslinking in granulation tissue; (3) chronic caloric restriction is associated with decreased collagen production and decreased levels of DHLNL; (4) the adverse effects of chronic caloric restriction on wound healing may have a greater impact on wound healing in old animals.