Endogenous programmed alveolar turnover in adult lung

描述（由申请人提供）：我们的长期目标是阐明 分子和细胞的基础，最近认识到的生理程序 成年哺乳动物肺中存在的肺泡的周转（损失和再生）; 并利用这些信息来诱导疾病中的肺泡形成。成人 在小鼠中，卡路里限制（CR）增加了个体肺泡的体积， 减少肺泡数量和表面积而不改变肺体积。CR 在72小时内导致肺DNA减少20%，至少部分原因是， 凋亡再喂养（RF）逆转了这些结构和细胞的变化。 因此，成年哺乳动物具有内源性程序来a）消除肺泡， 肺泡壁细胞和B）引起肺泡壁细胞的复制， 肺泡再生。我们的假设是基因表达的分析 在热量限制再喂养（CR-RF）诱导的细胞复制期间， 肺泡再生将确定基因和信号通路负责 肺泡形成为了验证我们的假设，我们的特定目标，使用成年小鼠 进行CR-RF，是：1）使用形态测量程序来检测的发病率 肺泡壁细胞的再生和复制，确定 复制肺泡壁细胞，并确定是否有差异， 在复制开始时的细胞类型。2)评估肺基因表达， 使用微阵列的肺泡壁细胞复制和肺泡再生 技术. 3)使用北方分析（N）、RNA酶保护试验（RPA）和 蛋白质印迹（W），以确认肺中的微阵列结果。为选定 基因和信号通路，使用N，RPA或W来确定是否相同的CR-RF 诱导的基因表达发生在a）相同小鼠的其他器官中（较少 重要基因），或B）在三种其它的肺特异性的方式中， 肺泡形成这些基因在肺泡形成过程中表达 将考虑在四种不同的肺泡形成模型中共享 最重要的4)操纵选定的基因和信号通路 尽可能地抑制，或通过敲除，并确定对a）的影响 CR-RF诱导的小鼠肺泡再生或B）对小鼠肺泡形成的影响 使用形态测量法随意饲喂未处理的野生型成年小鼠 程序.

DESCRIPTION (provided by applicant): Our long-term goal is to explicate the molecular and cellular basis for the recently recognized physiologic programmed turnover (loss and regeneration) of alveoli present in lungs of adult mammals; and, use this information to induce alveolus formation in disease. In adult mice, calorie restriction (CR) increases the volume of individual alveoli and diminishes alveolar number and surface area without altering lung volume. CR causes, within 72 h, a 20 percent decrease in lung DNA due, at least partly, to apoptosis. Refeeding (RF) reverses these architectural and cellular changes. Thus, adult mammals have endogenous programs to a) eliminate alveoli and alveolar wall cells and b) cause replication of alveolar wall cells and regeneration of alveoli. Our hypothesis is that an analysis of gene expression during calorie restriction-refeeding (CR-RF) induced cell replication and alveolar regeneration will identify genes and signal pathways responsible for alveolus formation. To test our hypothesis, our Specific Aims, using adult mice subjected to CR-RF, are: 1) Use morphometric procedures to detect the onset of alveolar regeneration and replication of alveolar wall cells, identify the replicating alveolar wall cells, and determine if there are differences among cell types in the onset of replication. 2) Assess lung gene expression during alveolar wall cell replication and alveolar regeneration using microarray technology. 3) Use Northern analysis (N), Rnase protection assay (RPA), and Western blotting (W), to confirm microarray results in the lung. For selected genes and signal pathways, use N, RPA, or W to determine if the same CR-RF induced gene expression occurs a) in other organs of the same mice (less important genes), or b) in a lung specific manner in three other models of alveolus formation. Those genes whose lung expression during alveolus formation is shared among four different models of alveolus formation will be considered most important. 4) Manipulate selected genes and signal pathways pharmacologically when possible, or by knockout, and determine the effect on a) CR-RF-induced alveolar regeneration in mice or b) on alveolus formation in adult otherwise untreated wild-type mice fed ad libitum using morphometric procedures.