Effect of Organophoshate Exposure on Cholesteryl Ester Hydrolase

有机磷酸盐暴露对胆固醇酯水解酶的影响

• 批准号: 7811262
• 负责人: MATTHEW K ROSS
• 金额: $ 6.72万
• 依托单位: MISSISSIPPI STATE UNIVERSITY
• 依托单位国家: 美国
• 财政年份: 2009
• 资助国家: 美国
• 起止时间: 2009-09-25 至 2011-07-31
• 项目状态: 已结题
• 来源: https://reporter.nih.gov/project-details/7811262
• 关键词: 2-arachidonylglycerol; Aftercare; Age; Agonist; Agriculture; American Heart Association; Animal Disease Models; Area; Arterial Fatty Streak; Arteries; Atherosclerosis; Bile fluid; Binding; Biochemical Reaction; Biochemistry; CNR1 gene; CNR2 gene; Cannabinoids; Carboxylic Ester Hydrolases; Cardiology; Cardiovascular Diseases; Cause of Death; Cell Culture System; Cell Line; Cell Proliferation; Cells; Chlorpyrifos; Cholesterol; Cholesterol Esters; Cholesterol Homeostasis; Chronic; Combined Modality Therapy; Complex; Connective Tissue; Coronary Arteriosclerosis; Coronary artery; Country; Data; Databases; Development; Disease; Dose; Endocannabinoids; Environmental Health; Environmental Risk Factor; Enzymes; Esters; Exposure to; Family; Florida; Foam Cells; Functional disorder; Funding; G-Protein-Coupled Receptors; Genbank; Goals; Grant; Healed; Health; High Density Lipoproteins; Human; Hydrolysis; Hypertension; Immune; Inflammation Mediators; Inflammatory; Insecticides; Investigation; Laboratories; Ligands; Lipid Binding; Lipids; Liver; Low-Density Lipoproteins; Marijuana; Mediating; Metabolism; Methyl Parathion; Mississippi; Modeling; Movement; Neuraxis; O,O-diethyl O-3,5,6-trichloro-2-pyridyl phosphate; Organophosphates; PTGS2 gene; Paraoxon; Parathion; Patients; Peripheral; Pesticides; Pharmacological Treatment; Phenotype; Physiological; Play; Prevalence; Process; Prostaglandins; Protein Isoforms; Proteins; Publishing; Recombinants; Recording of previous events; Regulation; Research; Research Project Grants; Risk; Risk Factors; Role; Serine; Serum; Severities; Smooth Muscle Myocytes; Southeastern United States; Stimulus; Stroke; Students; System; Testing; Tissues; Toxic Environmental Substances; Training; Transport Process; United States; United States National Institutes of Health; Universities; Work; Xenobiotics; adduct; anandamide; autocrine; base; cDNA Library; cannabinoid receptor; carboxylesterase; environmental chemical; environmental toxicology; esterase; extracellular; healing; human disease; low socioeconomic status; macrophage; member; monocyte; mortality; novel; oxidized low density lipoprotein; paracrine; parent grant; particle; prevent; progesterone 11-hemisuccinate-(2-iodohistamine); public health relevance; receptor; response; reverse cholesterol transport; statistics; suicide inhibitor; theories; toxic organophosphate insecticide exposure; toxicant; uptake

DESCRIPTION (provided by applicant): The rate-limiting step in reverse cholesterol transport from macrophages is the hydrolysis of cholesteryl esters to free cholesterol, which is subsequently transported out of the cell to cholesterol acceptors. In human macrophages, the enzyme responsible for cholesteryl ester hydrolysis is carboxylesterase 1 (CES1). The overall hypothesis of parent grant R15 ES015348 was that exposure to bioactive metabolites of organophosphate (OP) insecticides will inhibit the ability of CES1 to hydrolyze cholesteryl esters, thus slowing the reverse cholesterol transport process and increasing the risk of atherosclerosis. Our published data, obtained during the current funding cycle, shows that CES1 can be inhibited by treatment with paraoxon, the active metabolite of the OP insecticide parathion, and that this inhibition can cause augmented accumulation of cholesteryl esters in human THP-1 macrophages (Crow et al., 2008). Moreover, our recent preliminary data show that recombinant CES1 and CES2 can hydrolyze the endocannabinoid compound 2-arachidonoylglycerol (2-AG) and its COX-2 derived prostaglandin-like metabolites (termed prostaglandin glyceryl esters or PG-Gs). Pretreatment of human THP-1 monocytes and macrophages with paraoxon can block the subsequent degradation of exogenously added 2-AG and PG-Gs. These are novel findings that suggest that exposure of CES1- and/or CES2-expressing cells to bioactive OP metabolites (e.g., paraoxon) will perturb the endocannabinoid tone in tissues composed of these cells. It has become increasingly clear that endogenous cannabinoids, which bind to the same class of receptors as the psychoactive component of marijuana (?9-THC), have important functions in health and disease. Therefore, we hypothesize that the endocannabinoid tone of vessel wall macrophages will be significantly perturbed by chronic exposure to bioactive OP metabolites and an activated endocannabinoid system can modulate cholesterol metabolism in macrophages. To explore this possibility, we propose to extend the scope of R15 ES015348 by studying the endocannabinoid system in a model cell culture system (macrophage foam cells) that we already use in the parent grant. To test our hypothesis we propose two aims: (1) Determine if combined treatment of cultured human THP-1 macrophages with oxidized (ox)LDL and bioactive metabolites of OP pesticides modulate components of the endocannabinoid system, including cannabinoid (CB) receptor levels, endocannabinoid biosynthetic enzymes, endocannabinoid catabolic enzymes (MAGL and CES1), and the levels of endocannabinoids themselves (2-AG and AEA). (2) Determine if endocannabinoids (2-AG and AEA) modulate cholesterol metabolism and efflux from human macrophages via a CB1- or CB2-mediated mechanism. PUBLIC HEALTH RELEVANCE: Atherosclerosis is the number one killer in the United States. The underlying pathophysiology of atherosclerosis is complex and multifactorial. One critical factor in the development/progression of atherosclerosis is environmental factors, such as toxicants, that may accelerate disease. Our research seeks to examine whether organophosphate (OP) pesticides are etiologically associated with atherosclerosis. Our research indicates that there are enzymes that regulate cholesterol metabolism, which can be inhibited by bioactive metabolites of OP pesticides. This competitive supplement will allow us to study these mechanisms in greater detail.

描述（由申请方提供）：巨噬细胞胆固醇逆向转运的限速步骤是胆固醇酯水解为游离胆固醇，随后将游离胆固醇转运出细胞至胆固醇受体。在人类巨噬细胞中，负责胆固醇酯水解的酶是羧酸酯酶1（CES 1）。母公司授权R15 ES 015348的总体假设是，暴露于有机磷酸盐（OP）杀虫剂的生物活性代谢物将抑制CES 1水解胆固醇酯的能力，从而减缓胆固醇逆向转运过程并增加动脉粥样硬化的风险。我们在当前资助周期期间获得的公开数据显示，CES 1可以通过用对氧磷（OP杀虫剂敌百虫的活性代谢物）处理而被抑制，并且这种抑制可以导致胆固醇酯在人THP-1巨噬细胞中的积累增加（Crow等人，2008年）。此外，我们最近的初步数据表明，重组CES 1和CES 2可以水解内源性大麻素化合物2-花生四烯酸甘油（2-AG）及其考克斯-2衍生的类前列腺素代谢产物（称为前列腺素甘油酯或PG-Gs）。用对氧磷预处理人THP-1单核细胞和巨噬细胞可阻断外源性2-AG和PG-Gs的后续降解。这些是新的发现，表明表达CES 1和/或CES 2的细胞暴露于生物活性OP代谢物（例如，对氧磷）将扰乱由这些细胞组成的组织中的内源性大麻素的张力。越来越清楚的是，内源性大麻素与大麻的精神活性成分（？9-THC），在健康和疾病中具有重要作用。因此，我们假设血管壁巨噬细胞的内源性大麻素音调将受到慢性暴露于生物活性OP代谢物的显著干扰，并且活化的内源性大麻素系统可以调节巨噬细胞中的胆固醇代谢。为了探索这种可能性，我们建议通过研究我们已经在母基金中使用的模型细胞培养系统（巨噬细胞泡沫细胞）中的内源性大麻素系统来扩展R15 ES 015348的范围。为了验证我们的假设，我们提出了两个目标：（1）确定培养的人THP-1巨噬细胞与氧化（ox）LDL和OP农药的生物活性代谢物的组合处理是否调节内源性大麻素系统的组分，包括大麻素（CB）受体水平，内源性大麻素生物合成酶，内源性大麻素分解酶（MAGL和CES 1），以及内源性大麻素本身的水平（2-AG和AEA）。(2)确定内源性大麻素（2-AG和AEA）是否通过CB 1或CB 2介导的机制调节胆固醇代谢和从人巨噬细胞流出。 公共卫生相关性：动脉粥样硬化是美国的头号杀手。动脉粥样硬化的基础病理生理学是复杂和多因素的。动脉粥样硬化的发展/进展中的一个关键因素是环境因素，例如可能加速疾病的毒物。我们的研究旨在探讨有机磷农药是否与动脉粥样硬化的病因学相关。我们的研究表明，有调节胆固醇代谢的酶，这可以被OP农药的生物活性代谢产物抑制。这种竞争性补充将使我们能够更详细地研究这些机制。