Retinoic Acid Contribution to Embryonic Gastrointestinal Tract Development

视黄酸对胚胎胃肠道发育的贡献

• 批准号: 9134124
• 负责人: Naomi EB Tjaden
• 金额: $ 4.86万
• 依托单位: UNIVERSITY OF KANSAS MEDICAL CENTER
• 依托单位国家: 美国
• 财政年份: 2014
• 资助国家: 美国
• 起止时间: 2014-06-01 至 2017-05-31
• 项目状态: 已结题
• 来源: https://reporter.nih.gov/project-details/9134124
• 关键词: Abdomen; Accounting; Address; Affect; Alleles; Animal Model; Animals; Apoptosis; Biological Assay; Candidate Disease Gene; Cartilage; Cell Lineage; Cell Proliferation; Cells; Clinical; Colonic Aganglionosis; Complex; Congenital Abnormality; Congenital Megacolon; Constipation; Defect; Development; Developmental Process; Diet Modification; Disease; Disease model; Embryo; Embryonic Development; Enteral; Enteric Nervous System; Enzymes; Etiology; Excision; Failure; Fetal Death; Gastrointestinal tract structure; Genes; Goals; Health; Human; Immunohistochemistry; In Situ Hybridization; Incidence; Intestines; Investigation; Knock-out; Knockout Mice; Knowledge; Lead; Length; Live Birth; Meconium; Metabolism; Modeling; Molecular; Morbidity - disease rate; Morphogenesis; Mus; Mutate; Mutation; Neural Crest Cell; Neuroglia; Neurons; Operative Surgical Procedures; Organogenesis; Pathogenesis; Pathway interactions; Patients; Pattern; Peripheral; Population; Pregnancy; Preventive measure; Reaction; Regulatory Pathway; Reporter; Research; Retinal; Retinoids; Retinol dehydrogenase; Role; Series; Signal Pathway; Signal Transduction; Signaling Molecule; Smooth Muscle; Staging; Study models; Supplementation; Tamoxifen; Testing; Tretinoin; Vitamin A; Vitamin A Deficiency; bone; cell type; congenital anomaly; craniofacial; disease phenotype; epithelial to mesenchymal transition; gastrointestinal; gastrointestinal system; improved; in utero; innovation; melanocyte; migration; mortality; mouse model; mutant; nervous system development; neural plate; novel; oxidation; relating to nervous system; research study; spatiotemporal; transcriptome sequencing

DESCRIPTION (provided by applicant): Project Summary Hirsch sprung disease (HSCR) is a congenital absence of neurons in a portion of the intestinal tract, due to a failure of neural cres cell (NCC) colonization or development. This anomaly occurs in 1/5000 live births, and typically requires surgical resection of the a ganglionic bowel. Only half of the HSCR cases are attributable to known genetic defects, and it is therefore necessary to explore other pathways and potential modifiers of this disease. The proposed studies investigate the role of vitamin A metabolism in NCC and gastrointestinal tract development using new animal models of retinoid deficiency. I will test the hypothesis that RDH10 has a significant impact on the RA synthesis necessary for organogenesis, specifically on NCC proliferation, differentiation or migration during formation of the enteric nervous system (ENS). Specifically, this project addresses the effects of retinoid deficiency in an allelic series of mice as well as investigates the cause and potential rescue of HSCR. Aim 1 will define the temporal and spatial requirements for retinoid signaling during gut development, testing our hypothesis that RA signaling is spatiotemporally required for proper ENS formation. This is relevant, as Vitamin A deficiency can occur prior to and during pregnancy and can affect NCC development, resulting in congenital anomalies that may include HSCR. Hence it is critical to understand which stage of NCC development requires retinoid signaling during ENS formation and gut development. RDH10 is a retinol dehydrogenase enzyme required for the first oxidation step of vitamin A to retinoic acid (RA). We hypothesize in Aim 2 that RDH10 is required for the initial migration of neural crest cells, and without proper RA signaling, NCCs do not receive the appropriate guidance signals required to colonize the gut and form a normal ENS. We utilize retinoid supplementation both in culture and via in utero gavage supplementation, along with conditional knockout mice to define the temporal requirement for RA signaling. Our results will act as a springboard for understanding the cellular and molecular mechanisms underlying defective ENS development in RDH10-deficient mice, as well as determine the interactions of RA on known enteric NCC regulatory pathways and gut microenvironment. We will use immunohistochemistry and in situ hybridization on whole embryos, guts, cultured guts, and sections to assay for enteric NCC proliferation, apoptosis, migration, and differentiation, as well as for genes known to contribute to these developmental processes, alongside a combination of candidate gene and RNA sequencing approaches. Results from these studies will establish a new model for studying HSCR, providing information regarding the spatiotemporal requirements for RA during embryonic intestinal development, the pathogenic cellular mechanisms of RDH10 deficient animals, as well as the interactions of RA with pathways that govern normal ENS NCC colonization. This knowledge may lead to innovative non-surgical treatments to reduce the morbidity and mortality of this common congenital disease.

描述（由申请人提供）：项目总结先天性巨结肠症（HSCR）是由于神经克雷斯细胞（NCC）定植或发育失败导致的部分肠道先天性神经元缺失。这种异常发生在1/5000的活产婴儿中，通常需要手术切除a节肠。只有一半的HSCR病例可归因于已知的遗传缺陷，因此有必要探索这种疾病的其他途径和潜在修饰因素。拟议的研究调查的作用，维生素A代谢的NCC和胃肠道的发展，使用新的动物模型，维生素A缺乏症。 我将测试的假设，RDH 10有一个显着的影响RA合成所需的器官，特别是NCC增殖，分化或迁移过程中形成的肠神经系统（ENS）。具体而言，该项目解决了维甲酸缺乏症在一系列等位基因小鼠中的影响，并调查了HSCR的原因和潜在的救援。目的1将定义类维生素A信号在肠道发育过程中的时间和空间要求，测试我们的假设，RA信号是时空需要适当的ENS形成。这是相关的，因为维生素A缺乏症可能发生在怀孕之前和怀孕期间，并可能影响NCC的发育，导致先天性异常，可能包括HSCR。因此，了解NCC发育的哪个阶段需要ENS形成和肠道发育过程中的类维生素A信号是至关重要的。RDH 10是维生素A氧化为视黄酸（RA）的第一步所需的视黄醇脱氢酶。我们假设在目标2，RDH 10是所需的神经嵴细胞的初始迁移，没有适当的RA信号，NCC不接受所需的适当的指导信号，殖民肠道，形成一个正常的ENS. We利用维甲酸的补充，无论是在文化和通过在子宫内灌胃补充，沿着与条件敲除小鼠，以确定RA信号的时间要求。我们的研究结果将作为一个跳板，了解RDH 10缺陷小鼠中ENS缺陷发展的细胞和分子机制，以及确定RA对已知肠道NCC调控途径和肠道微环境的相互作用。我们将使用免疫组织化学和原位杂交对整个胚胎，肠道，培养的肠道，和部分来测定肠NCC增殖，凋亡，迁移和分化，以及已知有助于这些发育过程的基因，以及候选基因和RNA测序方法的组合。 这些研究的结果将建立一个新的模型，研究HSCR，提供有关RA在胚胎肠道发育的时空要求，RDH 10缺陷动物的致病细胞机制，以及RA与正常ENS NCC定植途径的相互作用的信息。这些知识可能会导致创新的非手术治疗，以减少这种常见的先天性疾病的发病率和死亡率。