The role of the C1P/cPLA2alpha interaction in anaphylaxis

C1P/cPLA2α 相互作用在过敏反应中的作用

基本信息

批准号：
8700081
负责人：
CHARLES E. CHALFANT
金额：
$ 22.88万
依托单位：
VIRGINIA COMMONWEALTH UNIVERSITY
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：
2014-02-13 至 2016-01-31
项目状态：
已结题

来源：
https://reporter.nih.gov/project-details/8700081
关键词：
Age Aging Agonist Allergens Allergic Reaction Amino Acid Sequence Amino Acids Anabolism Anaphylaxis Applications Grants Arachidonic Acids Binding C2 Domain Cardiovascular Diseases Cell physiology Cells Cytosolic Phospholipase A2 Data Development Disease Docosahexaenoic Acids Eicosanoids Eicosapentaenoic Acid Elderly Enzymes Event Exposure to Future Genetic Models In Vitro Incidence Inflammation Inflammation Mediators Inflammatory Inflammatory Response Knockout Mice Laboratories Leukotrienes Lipids Literature Mediating Mediator of activation protein Membrane Mus Mutagenesis Mutate Omega-3 Fatty Acids Pathway interactions Pattern Phenotype Phospholipase Phospholipase A2 Physiological Play Population Production Prostaglandins Prostaglandins I Proteins Reporting Resistance Role Site Sphingolipids Spontaneous abortion Thromboxanes Wild Type Mouse autocrine base cell type ceramide 1-phosphate ceramide kinase combat effective therapy in vivo lipid mediator mast cell mouse model novel novel therapeutics paracrine public health relevance research study response

项目摘要

DESCRIPTION (provided by applicant): In this grant application, we are focusing on the physiological condition of anaphylaxis, which is a severe, systemic allergic reaction that occurs quickly upon exposure to an allergen. The incidence rate has increased dramatically to 49.8 people per 100,000, many of which are elderly with comorbid conditions such as cardiovascular disease. The studies proposed in this grant application are directly related to anaphylaxis as we are examining the biosynthetic pathways of eicosanoids and other lipid mediators. These bioactive lipids are well known to be involved in inflammatory pathways as well as mediating mast cell activation and degranulation during anaphylactic responses. The synthesis of eicosanoids begins with the initial rate-limiting step, the formation of arachidonic acid (AA) via group IVA cytosolic phospholipase A2 (cPLA2a). Ceramide-1- phosphate (C1P) is a bioactive sphingolipid and a direct activator of cPLA2a both in vitro and in cells. Mutagenesis of critical amino acids for C1P interaction in cPLA2a inhibited the ability of enzyme to translocate in response to several inflammatory agonists. Hence, the association of cPLA2a with C1P is a major regulatory event in the biosynthesis of bioactive lipid mediators (e.g. eicosanoids). To further our understanding of the physiological relevance of this lipid:protein interaction in vivo, our laboratory created a knockin mouse with the C1P interaction site of cPLA2a ablated. Our preliminary data has demonstrated some intriguing findings for this new genetic model of cPLA2a. For example, some phenotypes reported for the cPLA2a knockout mouse were not apparent in the cPLA2a knockin mouse (e.g. spontaneous abortion) [14], while other phenotypes were conferred to the cPLA2a knockin mouse such as resistance to passive systemic anaphylaxis. Based on these preliminary findings by our laboratory and inferences from the literature, we hypothesize that the cPLA2a knockin mouse is resistant to anaphylaxis due to loss of specific lipid mediators. We further hypothesize that though wild type mice have an increased anaphylactic phenotype as they age, the cPLA2a knockin mice will remain resistant. Our proposed experiments will explore this hypothesis in depth both ex vivo and in vivo with the hope of developing new therapeutics to combat this disease state in both young and aging populations.

描述（由申请人提供）：在本赠款申请中，我们关注过敏反应的生理状况，过敏反应是一种严重的全身过敏反应，在暴露于过敏原时会迅速发生。发病率急剧增加到每100,000人的49.8人，其中许多人具有合并症，例如心血管疾病。当我们研究类花生酸和其他脂质介质的生物合成途径时，本赠款应用中提出的研究与过敏反应直接相关。众所周知，这些生物活性脂质参与炎症途径，并在过敏反应过程中介导肥大细胞的激活和脱粒。类固醇的合成始于初始速率限制步骤，即通过IVA胞质胞质磷脂酶A2（CPLA2A）形成蛛网膜酸（AA）（AA）。神经酰胺1-磷酸盐（C1P）是一种生物活性鞘脂，并且在体外和细胞中都是CPLA2A的直接激活剂。 CPLA2A中C1P相互作用的临界氨基酸的诱变抑制了酶以响应几种炎性激动剂而易位的能力。因此，CPLA2A与C1P的关联是生物活性脂质介质生物合成的主要调节事件（例如，生体类动物）。为了进一步了解这种脂质的生理相关性：体内蛋白质相互作用，我们的实验室用CPLA2A的C1P相互作用烧蚀了一只敲击小鼠。我们的初步数据证明了这一新的CPLA2A遗传模型的有趣发现。例如，在CPLA2A敲除小鼠（例如自发流产）中，报道的CPLA2A基因敲除小鼠报告的某些表型不明显[14]，而其他表型则赋予CPLA2A敲除小鼠，例如对被动全身性过敏反应的抗性。基于我们的实验室的这些初步发现和文献推论，我们假设CPLA2A敲击蛋白小鼠由于特定脂质介质的丧失而对过敏反应具有抗性。我们进一步假设，尽管随着年龄的增长，野生型小鼠的过敏表型增加，但CPLA2A敲击蛋白小鼠将保持抗性。我们提出的实验将在体内和体内深入探讨这一假设，希望开发新的治疗疗法以对抗年轻人和衰老的人群中这种疾病状态。