The Role of ES-4 in the Hydrolysis of Cholesteryl Ester in Hepatic Cells

ES-4 在肝细胞胆固醇酯水解中的作用

• 批准号: 7404622
• 负责人: SAJESH PARATHATH
• 金额: $ 4.96万
• 依托单位: NEW YORK UNIVERSITY SCHOOL OF MEDICINE
• 依托单位国家: 美国
• 财政年份: 2007
• 资助国家: 美国
• 起止时间: 2007-02-01 至 2010-01-31
• 项目状态: 已结题
• 来源: https://reporter.nih.gov/project-details/7404622
• 关键词: Agonist; Alzheimer' s Disease; Arteries; Atherosclerosis; Back; Basic Science; Bile Acids; Bile fluid; Binding Sites; Biological Assay; Cardiovascular Diseases; Cause of Death; Cell Line; Cell physiology; Cells; Cessation of life; Cholesterol; Cholesterol Esters; Cholesterol Homeostasis; Clinical; Coronary heart disease; Data; Disease; Environment; Equilibrium; Esterification; Functional disorder; Gene Expression; Genes; Goals; Hepatic; Hepatocyte; High Density Lipoproteins; Hormones; Hydrolase; Hydrolysis; Incidence; Lipids; Liver; Lysosomes; Measurement; Measures; Mediating; Membrane; Messenger RNA; Metabolism; Myocardial Infarction; Names; Nucleic Acid Regulatory Sequences; Pathway interactions; Play; Production; Protein Overexpression; Proteins; RXR; Radiolabeled; Rat Protein; Regulation; Reporter; Research; Role; Site; Small Interfering RNA; Standards of Weights and Measures; Steroids; Stroke; Technology; Testing; Transcript; Transcriptional Regulation; Transfection; United States; base; cholesterol control; esterase; lipid metabolism; mRNA Expression; prevent; promoter; protein expression; protein function; radiotracer; reconstitution; research study; response; reverse cholesterol transport; transcription factor; uptake

DESCRIPTION (provided by applicant): Cardiovascular disease in the United States is the leading cause of death (AHA). The long term objective of this research study is to understand basic cholesterol metabolism in order to prevent and combat diseases of cholesterol dysfunction such as atherosclerosis (heart attack, stroke), Newman Pick-C and Alzheimer's. The ability of cells to control cholesterol levels is a balance between the de novo synthesis and uptake of cholesterol versus secretion and efflux of cholesterol. Excess cholesterol in cells is toxic and is neutralized by esterification and stored as cholesteryl esters (CE). Hydrolysis of CE is necessary for the utilization of cholesterol for bile synthesis, hormone production, efflux of excess cholesterol and many other cellular functions. Our hypothesis is that, ES-4 is a hepatic neutral cholesteryl ester hydrolase (NCEH), and propose the following experiments. In our first aim we seek to define and understand the contribution of ES- 4 in CE hydrolysis. ES-4 protein will be suppressed or overexpressed using siRNA or transfection strategies. Using hepatic cells with various ES-4 levels, CE turnover, cholesterol mass, selective uptake and direct measurements of CE hydrolysis will be determined. The second aim of the study tests the hypothesis that the 5-kb region upstream of ES-4 transcriptional start site contains regulatory regions and these regions are necessary for the induction elicited by cholesterol and LXR agonist. This hypothesis will be tested using cholesterol loading/unloading, treatments with LXR agonist in conjunction with reporter constructs. Identifying the hepatic NCEH has significant basic science and clinical implications; it provides a new target for reducing VLDL/LDL CE production and would provide further understanding of the hepatic cholesterol cycle. Atherosclerosis (hardening of arteries due to excess cholesterol) mediated diseases (heart attack and strokes) are the leading cause of illness and death in the United States (NHLBI). This proposal examines ES-4, potentially a key player in modulating cholesterol levels/metabolism in the liver. Research in cholesterol metabolism is vital when considering that decreasing total cholesterol levels by 10% may result in an estimated 30 percent reduction in the incidence of coronary heart disease (CDC-2000).

描述（由申请人提供）：美国的心血管疾病是死亡的主要原因（AHA）。这项研究的长期目标是了解基本的胆固醇代谢，以预防和对抗胆固醇功能障碍的疾病，例如动脉粥样硬化（心脏病发作，中风），纽曼·皮克 - C和阿尔茨海默氏病。细胞控制胆固醇水平的能力是从头合成与胆固醇的摄取与分泌与胆固醇外排的能力之间的平衡。细胞中过量的胆固醇有毒，并通过酯化被中和，并作为胆汁固醇​​酯（CE）储存。 CE的水解对于利用胆固醇的胆汁合成，激素产生，过量胆固醇的排出和许多其他细胞功能是必需的。我们的假设是，ES-4是一种肝中性胆固醇酯水解酶（NCEH），并提出以下实验。在我们的第一个目标中，我们试图定义和了解ES-4在CE水解中的贡献。 ES-4蛋白将使用siRNA或转染策略抑制或过表达。将确定使用具有各种ES-4水平，CE更新，胆固醇质量，选择性摄取和CE水解的直接测量的肝细胞。研究的第二个目的检验了以下假设：ES-4转录起始位点上游的5-KB区域包含调节区域，这些区域对于胆固醇和LXR激动剂引起的诱导是必需的。该假设将使用胆固醇加载/卸载，与记者结构结合使用LXR激动剂的处理。识别肝NCEH具有重要的基础科学和临床意义。它为减少VLDL/LDL CE生产提供了一个新的目标，并将进一步了解肝胆固醇周期。动脉粥样硬化（由于胆固醇过多而导致的动脉硬化）介导的疾病（心脏病发作和中风）是美国疾病和死亡的主要原因（NHLBI）。该提案研究了ES-4，这可能是调节肝脏中胆固醇水平/代谢的关键参与者。考虑到将总胆固醇水平降低10％时，胆固醇代谢的研究至关重要，可能会导致冠心病发病率降低30％（CDC-2000）。