Chondroitin Sulfate Proteoglycans in Lung Development

硫酸软骨素蛋白多糖在肺部发育中的作用

• 批准号: 6561358
• 负责人: JOHN M SHANNON
• 金额: $ 29.8万
• 依托单位: CINCINNATI CHILDRENS HOSP MED CTR
• 依托单位国家: 美国
• 财政年份: 2003
• 资助国家: 美国
• 起止时间: 2003-01-03 至 2006-11-30
• 项目状态: 已结题
• 来源: https://reporter.nih.gov/project-details/6561358
• 关键词: DNA replication; apoptosis; cell differentiation; cell proliferation; chondroitin sulfates; embryo /fetus tissue /cell culture; enzyme activity; gene expression; genetically modified animals; histogenesis; hyaluronidase; immunocytochemistry; laboratory mouse; lipid biosynthesis; lung; molecular cloning; mucopolysaccharides; nucleic acid purification; phospholipids; protein biosynthesis; protein structure function; proteoglycan; pulmonary surfactants; secretory protein; terminal nick end labeling

DESCRIPTION (provided by applicant): Normal lung development requires the temporally and spatially correct expression of numerous biologically-active molecules. Many of these molecules are soluble and include hormones, growth factors, bioactive peptides, and cytokines. Components of the insoluble extracellular matrix (ECM), including proteoglycans (PGs), have also been shown to play important roles in normal lung growth and differentiation. PGs are a diverse class of molecules that serve as structural substrata in which tissues develop, act as binding reservoirs for specific growth factors, and mediate such processes as cell-ECM, cell-cell, and ligand-receptor interactions. Our preliminary experiments have shown that sulfated PGs are required for lung morphogenesis and epithelial differentiation. Further experiments demonstrated that disrupting one subclass of PGs, chondroitin sulfate proteoglycans (CSPGs), had marked inhibitory effects on lung growth and branching in vitro. From these data we have hypothesized that CSPGs play an essential role(s) in normal lung development. In this proposal, we will test this hypothesis in two phases. In the first phase (Specific Aims 1 and 2), we will use in vitro models to confirm and extend our preliminary observations that inhibition of PGs suppresses lung growth, morphogenesis, and epithelial differentiation, and to define which effects are due to the disruption of CSPGs. In the second phase (Specific Aim 3), we will determine how our in vitro observations translate to lung development in vivo. Conditional expression of chimeric bacterial chondroitinase(s) targeted to the lungs of transgenic mice will allow us to assess the importance of CSPGs in three distinct phases of lung development in vivo: branching morphogenesis, maturation of the pulmonary surfactant system, and postnatal alveolization. Completion of this project will fill a significant gap in our understanding of the role of CSPGs in lung morphogenesis and differentiation, and will determine whether disruption of CSPGs causes lung pathologies similar to clinical disease in neonates. This knowledge will allow the development of new strategies for the prevention and treatment of lung diseases resulting from lung hypoplasia and immaturity.

描述（由申请人提供）：正常的肺部发育需要大量生物活性分子在时间和空间上的正确表达。其中许多分子是可溶的，包括激素、生长因子、生物活性肽和细胞因子。不溶性细胞外基质 (ECM) 的成分，包括蛋白聚糖 (PG)，也已被证明在正常肺生长和分化中发挥重要作用。 PG 是一类不同的分子，可作为组织发育的结构基质，作为特定生长因子的结合库，并介导细胞-ECM、细胞-细胞和配体-受体相互作用等过程。我们的初步实验表明，硫酸化 PG 是肺形态发生和上皮分化所必需的。进一步的实验表明，破坏 PG 的一个亚类——硫酸软骨素蛋白聚糖 (CSPG)，对体外肺生长和分支具有显着的抑制作用。根据这些数据，我们假设 CSPG 在正常肺部发育中发挥重要作用。在本提案中，我们将分两个阶段检验这一假设。在第一阶段（具体目标 1 和 2），我们将使用体外模型来确认和扩展我们的初步观察结果，即抑制 PG 会抑制肺生长、形态发生和上皮分化，并确定哪些影响是由于 CSPG 的破坏造成的。在第二阶段（具体目标 3），我们将确定如何将体外观察结果转化为体内肺部发育。针对转基因小鼠肺部的嵌合细菌软骨素酶的条件表达将使我们能够评估 CSPG 在体内肺发育的三个不同阶段中的重要性：分支形态发生、肺表面活性剂系统的成熟和出生后肺泡化。该项目的完成将填补我们对 CSPG 在肺形态发生和分化中的作用的理解上的重大空白，并将确定 CSPG 的破坏是否会导致与新生儿临床疾病类似的肺部病理。这些知识将有助于制定预防和治疗由肺发育不全和不成熟引起的肺部疾病的新策略。