Mechanisms of regulation of retinoic acid homeostasis

视黄酸稳态的调节机制

基本信息

批准号：
9300950
负责人：
Nina Isoherranen
金额：
$ 28.45万
依托单位：
UNIVERSITY OF WASHINGTON
依托单位国家：
美国
项目类别：
财政年份：
2014
资助国家：
美国
起止时间：
2014-09-01 至 2018-09-14
项目状态：
已结题

来源：
https://reporter.nih.gov/project-details/9300950
关键词：
Adult Adverse effects Affect Alzheimer&apos s Disease B-Lymphocytes Bile Acids Binding Proteins Biochemical Biochemical Process Biological Biological Process CYP26B1 gene Cell Cycle Cell Cycle Regulation Cells Cessation of life Childhood Chordata Clinical Coupled Cytochrome P450 Development Diet Disease Disease Progression Drug Kinetics Drug Targeting Embryonic and Fetal Development Enzyme Kinetics Enzyme Tests Enzymes Epithelial Epithelium Foundations Future Gene Expression Regulation Generations Genetic Genetic Polymorphism Germ Cells Glucose Goals Growth Health Hepatocyte Hereditary Disease Homeostasis Human Ichthyoses Immunocompetence Impairment In Vitro Individual Islets of Langerhans Kidney Kidney Diseases Kinetics Knock-out Knockout Mice Knowledge Lead Life Lipids Liver Lung Maintenance Mass Spectrum Analysis Measures Mediating Metabolism Methods Modeling Mus Neurodegenerative Disorders Organ Overdose Pancreas Pharmaceutical Preparations Pharmacology Pharmacology Study Phenotype Physiological Physiology Play Process Psoriasis Public Health Regulation Reproduction Retinoids Role Signal Transduction Signaling Molecule System Testing Tissue Differentiation Tissue Sample Tissues Toxic Environmental Substances Toxic effect Tretinoin Vitamin A Vitamin Deficiency Weight Gain Whole Organism Work Xenobiotics adverse outcome aldehyde dehydrogenases base blood glucose regulation cell type cellular retinoic acid binding protein direct application enzyme activity experimental study glucose metabolism improved in vivo inhibitor/antagonist lipid metabolism novel novel therapeutic intervention pharmacokinetic model physiologic model podocyte protein protein interaction public health relevance retinoic acid 4-hydroxylase skin disorder tissue repair tool

项目摘要

DESCRIPTION (provided by applicant): All-trans-retinoic acid (atRA), the biologically active metabolite of dietary Vitamin A, is essential for mediating diverse biological functions in multipl tissues such as the liver, kidney, lung and pancreas. The different biological actions of atRA are regulated through tissue concentration gradients of atRA, but there are considerable gaps in our knowledge on how the tissue specific signaling of atRA is regulated during childhood and adult life. We propose that atRA concentration gradients are generated by regulated expression and activity of the enzymes synthesizing atRA (ALDH1As), those that metabolize atRA (CYP26s) and cellular retinoic acid binding proteins (CRABPs). Our central hypothesis is that alterations in the activity or expression of these enzymes change atRA signaling and distribution, contribute to disease development in specific tissues and result in adverse effects. To test this hypothesis we will first characterize atRA metabolism in cell systems and establish the role of cellular retinoic acid binding proteins (CRABPs) in modulating atRA clearance, signaling and distribution. We will use basic biochemical and enzyme kinetic methods and in vitro cell experiments to establish the role and kinetics of direct protein-protein interactions between CYP26s and CRABPs. We will then establish the tissue and cell type specific roles of ALDH1A, CYP26 and CRABP enzymes in maintaining atRA homeostasis in humans and mice. This will be done using normal human and mouse tissues, novel high sensitivity mass spectrometry methods, generating new conditional knock-out mice of CYP26 enzymes, testing pharmacological effects of CYP26 and ALDH1A inhibitors and using physiologically based pharmacokinetic (PBPK) modeling. To determine the overall physiological importance of these enzymatic processes, we will use the knock-out mice and our pharmacological tools in vitro and in vivo, to demonstrate that altered CYP26 or ALDH1A activity impairs normal physiological atRA signaling in target tissues. We will focus on atRA signaling in the liver, kidney, pancreas and lung due to the existing knowledge that atRA signaling plays a fundamental role in these tissues. Together these studies will generate a new and unique integrative model of retinoid homeostasis that will be useful in evaluating and predicting the effects of xenobiotics, new therapeutic approaches, disease processes and genetic factors in altering tissue retinoid signaling. This will have major impact in improving human health as it has direct application in improving our understanding of the processes involved in lipid and glucose homeostasis in the liver and the pancreas, in development and treatment of nephropathies and in lung alveoli health. In addition, the knowledge gained through these studies will improve our understanding of the role of atRA signaling during childhood development and maturation, and can be extended to improve our understanding of the role of atRA in skin diseases such as psoriasis and ichthyosis and in neurodegenerative diseases such as Alzheimer's and dementia in which atRA signaling has been shown to be altered.

描述（由申请人提供）：饮食维生素A的生物活性代谢物的全反式反激酸（ATRA）对于介导肝脏，肾脏，肺和胰腺等多重组织中的多种生物学功能至关重要。 ATRA的不同生物学作用是通过ATRA的组织浓度梯度来调节的，但是关于在儿童期和成人生活中如何调节ATRA的组织特定信号的知识存在很大的差距。我们提出，ATRA浓度梯度是通过合成ATRA（ALDH1AS）的调节表达和活性而产生的，ATRA（ALDH1AS）代谢ATRA（CYP26S）和细胞视黄酸结合蛋白（Crabps）。我们的核心假设是改变这些酶的活性或表达改变了ATRA信号传导和分布，有助于特定组织中的疾病发展，并导致不良反应。为了检验该假设酸结合蛋白（Crabps）调节ATRA间隙，信号传导和分布。我们将使用基本的生化和酶动力学方法以及体外细胞实验来确定CYP26S和Crabps之间直接蛋白质 - 蛋白质相互作用的作用和动力学。然后，我们将建立ALDH1A，CYP26和CrabP酶在维持人类和小鼠中的ATRA稳态方面的组织和细胞类型特异性作用。这将使用普通的人类和小鼠组织，新型的高灵敏度质谱法，生成新的有条件的CYP26酶敲除小鼠，测试CYP26和ALDH1A抑制剂的药理学作用，并使用基于生理的药物动力学（PBPK）模型。为了确定这些酶促过程的总体生理重要性，我们将在体外和体内使用敲除小鼠和药理学工具，以证明改变CYP26或ALDH1A活性会损害靶组织中正常生理ATRA信号。由于现有的了解ATRA信号在这些组织中起着基本作用，因此我们将重点关注肝脏，肾脏，胰腺和肺的ATRA信号传导。这些研究将共同产生类维生素性稳态的新的独特综合模型，该模型将有助于评估和预测异生物生物，新的治疗方法，疾病过程和遗传因素在改变组织类视网想信号传导中的影响。这将对改善人类健康，因为它直接应用了我们对肝脏和胰腺中脂质和葡萄糖稳态涉及的过程的理解，在肾病和肺肺泡健康中的发展和治疗中。此外，通过这些研究获得的知识将提高我们对ATRA信号在儿童期发展和成熟过程中的作用的理解，并可以扩展到我们对ATRA在皮肤疾病中的作用（如牛皮癣和疾病）以及在阿尔茨海默氏症等神经退行性疾病等皮肤疾病中的作用的理解。