Are Endothelial Cell and Granulocyte Protein Arginine Deiminase 4 on the Pathway of Inflammasome-Activation, Advancing Myocardial Ischemia Reperfusion Injury?

内皮细胞和粒细胞蛋白精氨酸脱亚胺酶 4 是否在炎症小体激活途径中，促进心肌缺血再灌注损伤？

• 批准号: 440378203
• 负责人: Dr. Lukas Heger
• 金额: --
• 依托单位: Immune Disease Institute at Childrens Hospital Boston
• 依托单位国家: 德国
• 项目类别: Research Fellowships
• 财政年份: 2020
• 资助国家: 德国
• 起止时间: 2019-12-31 至 2022-12-31
• 项目状态: 已结题
• 来源: https://gepris.dfg.de/gepris/projekt/440378203?language=en
• 关键词: Endothelial; Cell; Granulocyte; Protein; Arginine

With the advances in percutaneous coronary intervention technology, the prognosis of patients with acute coronary syndrome has improved significantly over the last decades. However, approximately 6% of admitted patients do not survive hospital discharge and a decrease in cardiac function is still a common consequence of acute myocardial infarction, despite vigorous medical therapy. Increasing clinical and experimental evidence suggests that revascularisation itself triggers a pathological response termed myocardial ischemia-reperfusion (M/IR) injury. Experimental and clinical data suggests that MI/R injury may be responsible for up to 50% of the ultimate infarction area.Since the first description of M/IR injury by Jennings et al. in the 1960s it became evident that M/IR injury is an inflammatory-driven mechanism, in part depending on the infiltration of bone-marrow derived cells as well as the activation of classic inflammatory pathways. To unravel the pathophysiology of this process could help to attenuate M/IR injury. In 2014 Gao C. et al. discovered the activation of NLRP3-Inflammasome, a cytosolic protein complex that mediates the activation of pro-inflammatory caspases, ultimately resulting in the secretion of cytokines of the interleukin-1 family, in cardiac microvascular endothelial cells (CMECs) as a novel mechanism of MI/R injury. As of August 2019 Mishra N et al. showed that the Protein Arginine Deiminase 4 regulates NLRP3 Inflammasome activation in macrophages.In 2019 Wagner et al. demonstrated that NLRP3 Inflammasome activation plays an important role in the process of granulocyte Neutrophil Extracellular Traps (NETs) release, a form of defence mechanism originally intended to immobilize invading microorganisms consisting of a DNA scaffold decorated with granule-derived proteins. Over the years NETs have been implicated in a growing list of autoimmune and inflammatory conditions and in 2015 Ge L. et al. provided evidence for the existence of NETs in MI/R injury challenged myocardium. Whether endothelial cell and granulocyte Protein Arginine Deiminase 4 are on the pathway of Inflammasome activation and thus advancing myocardial ischemia reperfusion injury is yet to be established.The aim of the proposed project is to further investigate pro-inflammatory signalling pathways of MI/R injury in a mouse model using short-term ligation of the left anterior descending artery. Ex-vivo methods such as histology, gen expression analysis of blood and endothelial cells, protein analysis, flow cytometry and Immunofluorescence microscopy will be used. A comparative analysis of PAD4-/--, WT- and NLRP3-/-- mice will help to single out their individual function in MI/R injury potentially unveiling novel therapeutic modalities in attenuating MI/R injury.

随着经皮冠状动脉介入治疗技术的进步，急性冠状动脉综合征患者的预后在过去几十年中得到了显着改善。然而，大约 6% 的入院患者无法出院，尽管采取了积极的药物治疗，但心功能下降仍然是急性心肌梗死的常见后果。越来越多的临床和实验证据表明，血运重建本身会引发一种称为心肌缺血再灌注（M/IR）损伤的病理反应。实验和临床数据表明，MI/R 损伤可能导致高达 50% 的最终梗塞面积。自从 Jennings 等人首次描述 M/IR 损伤以来。在 20 世纪 60 年代，人们发现 M/IR 损伤是一种炎症驱动的机制，部分取决于骨髓来源细胞的浸润以及经典炎症途径的激活。阐明这一过程的病理生理学可能有助于减轻 M/IR 损伤。 2014年，Gao C.等人。发现 NLRP3-炎症小体（一种胞浆蛋白复合物，介导促炎性半胱天冬酶的激活，最终导致心脏微血管内皮细胞 (CMEC) 中白细胞介素-1 家族细胞因子的分泌）的激活是 MI/R 损伤的一种新机制。截至 2019 年 8 月，Mishra N 等人。表明蛋白质精氨酸脱亚胺酶 4 调节巨噬细胞中 NLRP3 炎症小体的激活。2019 年，Wagner 等人。证明 NLRP3 炎症小体激活在粒细胞中性粒细胞胞外陷阱 (NET) 释放过程中发挥重要作用，NET 是一种防御机制，最初旨在固定入侵的微生物，由装饰有颗粒衍生蛋白的 DNA 支架组成。多年来，NETs 与越来越多的自身免疫和炎症性疾病有关，2015 年 Ge L. 等人。为 MI/R 损伤心肌中存在 NET 提供了证据。内皮细胞和粒细胞蛋白精氨酸脱亚胺酶 4 是否在炎症小体激活途径上，从而促进心肌缺血再灌注损伤尚待确定。该项目的目的是通过短期结扎左前降支动脉，进一步研究小鼠模型中 MI/R 损伤的促炎信号传导途径。将使用诸如组织学、血液和内皮细胞的基因表达分析、蛋白质分析、流式细胞术和免疫荧光显微镜等离体方法。对 PAD4-/--、WT- 和 NLRP3-/-- 小鼠的比较分析将有助于找出它们在 MI/R 损伤中的个体功能，有可能揭示减轻 MI/R 损伤的新治疗方式。