Said Hakim K, Roy Nakshatra K, Gurjala Anandev N, Mustoe Thomas A
Division of Plastic Surgery, University of Washington, Seattle, Washington, USA.
Wound Repair Regen. 2009 Jul-Aug;17(4):473-9. doi: 10.1111/j.1524-475X.2009.00498.x.
Ischemia is a common underlying factor in a number of pathologic conditions ranging from cardiac dysfunction to delayed wound healing. Previous efforts have shown the resulting hypoxia activates the hypoxia inducible factor, a transcription factor with signaling effects through an intranuclear hypoxia response element (HRE). We hypothesized that ischemic conditions should activate these hypoxic signaling pathways in a measurable manner. We tested our hypothesis using variations of an established rabbit ear ischemic wound model and an HRE-luciferase-reporter gene construct. This plasmid construct was transfected into the ears of young, female New Zealand White rabbits, harvested at day 7 and processed to yield a reactive solution. Luminometry was used to quantify luciferase expression in each solution as a marker for HRE activation in each wound. Quantitative readings of hypoxic signaling as measured by luminescence yielded profound and statistically significant differences between the various ischemic models. Our results suggest that the biologic systems for hypoxic signaling can be used to detect local ischemia. HRE-luciferase transfection is an effective tool for quantifying the degree of tissue hypoxia. The caudal ischemic rabbit ear model showed significantly higher levels of hypoxia. Use of a validated model that produces sufficient tissue levels of hypoxia is recommended for meaningful study of ischemic wound healing.
缺血是从心脏功能障碍到伤口愈合延迟等多种病理状况的常见潜在因素。先前的研究表明，由此产生的缺氧会激活缺氧诱导因子，这是一种通过核内缺氧反应元件（HRE）产生信号作用的转录因子。我们推测，缺血状况应以可测量的方式激活这些缺氧信号通路。我们使用已建立的兔耳缺血伤口模型的变体和HRE-荧光素酶报告基因构建体来验证我们的假设。将该质粒构建体转染到年轻雌性新西兰白兔的耳朵中，在第7天收获并处理以产生反应溶液。使用发光测定法对每种溶液中的荧光素酶表达进行定量，作为每个伤口中HRE激活的标志物。通过发光测量的缺氧信号定量读数在各种缺血模型之间产生了显著且具有统计学意义的差异。我们的结果表明，缺氧信号的生物系统可用于检测局部缺血。HRE-荧光素酶转染是定量组织缺氧程度的有效工具。尾部缺血兔耳模型显示出明显更高的缺氧水平。建议使用能产生足够组织缺氧水平的经过验证的模型，以进行有意义的缺血伤口愈合研究。
