Novel specialized pro-resolving lipid mediators in resolution of aortic aneurysms and rupture

项目摘要 腹主动脉瘤（AAA）的形成和随后的主动脉破裂可导致猝死， 严重的临床问题，目前没有已知的可用的医学治疗。我们最近的研究 表征了ω-3衍生脂质的专门促消退介质（SPM）的保护作用， 衍生物，即Resolvin（Rv）D1，其通过调节M1/M2有效地减弱AAA形成 巨噬细胞极化在这个建议中，我们将描述生物活性的表型和机制， SPM的同种型，即Resolvins（RvD 1）、Maresins（MaR-1）、Protectins（PD-1）和Lipoxins（LxB 4）， 可以解决主动脉瘤形成并预防主动脉破裂。首先，我们将测量 人AAA患者和来自小鼠实验AAA模型的主动脉组织 质谱联用液相色谱法（LC/ESI-MS/MS），这是一种灵敏的分析方法 用于脂质介质的定性和定量分析。然后，我们将描述协同作用的特征， 这些SPM生物活性同种型在我们的鼠AAA和主动脉破裂模型中的反应。最后我们将 描述SPM的生物活性同种型即RvD 1、MaR-1、PD-1和LxB 4的具体机制， 体内和体外研究。我们的初步数据表明，用MaR-1治疗可以预防 与主动脉平滑肌细胞-TGF-β1信号传导相关的动脉瘤形成进展。最近 有报道表明，氧化线粒体（mt）DNA作为一种损伤相关的模式分子， NET，但它仍然是AAA的特点。因此，MaR-1在促进巨噬细胞增殖中的作用可能是一个新的研究方向。 与NET相关的依赖性红细胞增多症（凋亡/坏死中性粒细胞的摄取过程） 还将在人AAA组织以及实验鼠模型中阐明AAA的形成。而且我们 将定量SPM相关的G蛋白偶联受体（GPCR），即（ALX/FPR 2、GPR 32、GPR 18和 ChemR 23）在AAA中的信号传导。具体地，RvD 1/FPR 2通过AMP活化蛋白激酶（AMPK）信号传导至 调节GM-CSF和HMGB 1的促炎巨噬细胞分泌将在AAA形成中被破译。 因此，我们将描述SPM治疗预形成动脉瘤和预防动脉瘤的独特能力。 通过调节RvD 1-FPR 2信号传导、mtDNA依赖性NETosis、促进 细胞增殖和调节SMC依赖性TGF-β1信号传导。这种多方面的有针对性的方法， 特异性SPM亚型证明了治疗慢性主动脉炎的临床适用治疗策略 通过靶向巨噬细胞、嗜中性粒细胞和平滑肌细胞来抑制炎症和血管重塑。我们 科学前提是对这些促消退脂质衍生介质的作用进行深入分析 在动脉瘤形成的慢性模型中。重要的是，我们将测试这些方法的严谨性和可重复性。 动物研究，以确定这些转变是否发生在人体组织使用离体主动脉外植体。

PROJECT SUMMARY Abdominal aortic aneurysms (AAA) formation and subsequent aortic rupture can lead to sudden death and is a significant clinical problem with no currently known medical treatments available. Our recent studies have characterized a protective role of specialized pro-resolving mediators (SPMs) that are ω-3-derived lipid derivatives i.e. Resolvin (Rv)D1 that effectively attenuates AAA formation via modulating the M1/M2 macrophage polarization. In this proposal, we will delineate the phenotype and mechanisms of bioactive isoforms of SPMs i.e. Resolvins (RvD1), Maresins (MaR-1), Protectins (PD-1) and Lipoxins (LxB4) that can lead to resolution of aortic aneurysm formation and prevent aortic rupture. First, we will measure SPMs in human AAA patients and aortic tissue from murine experimental AAA model via electrospray tandem mass spectrometry coupled to liquid chromatography (LC/ESI-MS/MS), which is a sensitive analytical methodology for the qualitative and quantitative analysis of lipid mediators. Then, we will the characterize the synergistic response of these SPM bioactive isoforms in our murine AAA and aortic rupture models. Finally, we will delineate the specific mechanisms of the bioactive isoforms of SPMs i.e. RvD1, MaR-1, PD-1 and LxB4 using in vivo and in vitro studies. Our preliminary data demonstrates that treatment with MaR-1 can prevent the progression of aneurysm formation that is associated with aortic smooth muscle cell-TGF-β1 signaling. Recent reports suggest that oxidized mitochondrial (mt) DNA acts as a damage associated pattern molecule to form NETs, but it remains to be characterized in AAAs. Therefore, the role of MaR-1 in promoting macrophage- dependent efferocytosis (the process of uptake of apoptotic/necrotic neutrophils) associated with NET formation will also be elucidated in human AAA tissue as well as experimental murine models. Moreover, we will quantify SPM-related G-protein coupled receptors (GPCR) i.e. (ALX/FPR2, GPR32, GPR18, and ChemR23) signaling in AAA. Specifically, RvD1/FPR2 signaling via AMP-activated protein kinase (AMPK) to regulate pro-inflammatory macrophage secretion of GM-CSF and HMGB1 will be deciphered in AAA formation. Therefore, we will characterize the unique ability of SPMs to treat preformed aneurysms and prevent aortic rupture by modulating RvD1-FPR2 signaling, mtDNA-dependent NETosis, promoting efferocytosis and modulating SMC-dependent TGF-β1 signaling. This multi-faceted targeted approach of specific SPM isoforms demonstrate a clinically applicable therapeutic strategy for treatment of chronic aortic inflammation and vascular remodeling by targeting macrophages, neutrophils and smooth muscle cells. Our scientific premise is to perform an in-depth analysis of the roles of these pro-resolving lipid derived mediators in the chronic models of aneurysm formation. Importantly, we will test the rigor and reproducibility of these animal studies to determine whether these transitions occur in human tissue using ex vivo aortic explants.