"Glycoprotein involvement in cardiac fibrobiast-myocyte communication "

冠状动脉阻塞可导致心脏病发作(急性心肌梗死；毫升) 心肌组织的永久性丢失。结果是复杂的心脏结构遭到破坏， 疤痕组织的形成和心肌重塑增加了死亡的风险。心脏的初始反应 损伤是同步的，部分涉及心脏成纤维细胞和心脏细胞之间的相互作用。 心肌细胞，构成心脏的两种主要细胞类型。最近的发现表明，可溶性蛋白质 心脏成纤维细胞和心肌细胞分泌的物质，也称为分泌体，可以调节心肌梗死 微环境(细胞外基质)。细胞表面不仅是一道物理屏障 但感觉到局部细胞外基质微环境启动了内在的细胞保护机制 受伤。因此，细胞-环境界面是这种相互作用的主要场所。我们假设 成纤维细胞是关键，它们对损伤的反应启动了伤口的愈合，同时也促进了心肌细胞 生死存亡。成纤维细胞通过改变肌细胞周围的细胞外基质微环境来实现这一点， 尤其是那些出现在梗塞边缘区域的。构成细胞环境的许多蛋白质 界面是糖基化的。在这项建议中，我们将运用多项创新方法，有针对性地、丰富 定量(相对和绝对)和表征细胞-环境界面的糖蛋白质组 心肌细胞和成纤维细胞单独和在有或没有过氧化氢损伤的情况下共同培养。这包括使用 共培养时的一种新的扭曲，其中来自一种细胞类型的蛋白质具有共价定量标记 这为区分每个蛋白质的细胞来源提供了一个质谱学友好的标记。我们 假设组成细胞-环境界面的细胞特异性糖蛋白组负责 与成纤维细胞相比，心肌细胞对H_2O_2的内在敏感性(SA_1)。此外，它的一个子集 在共培养中升高的成纤维细胞特异性分泌蛋白诱导心肌细胞保护，这 当成纤维细胞自身受到损伤时，保护性表型会增强(SA-2)。最后， 我们假设糖蛋白存在于微环境中，它只在 心肌损伤(缺血)患者的循环中将检测到过氧化氢的反应 心肌肌钙蛋白升高(毫升的金标准标记物)。综上所述，补体的蛋白质 心脏成纤维细胞和心肌细胞的细胞-环境界面尚未完全阐明。这 知识是开发临床方法以保护心脏并潜在地提供 强健的临床生物标志物 相关性(见说明)； 这是第一次系统分析组成黄瓜分泌体和细胞表面的糖蛋白。 肌细胞和成纤维细胞是心脏的两种主要细胞类型，它们之间的相互作用是协同的，可以 对心肌细胞有保护作用。这些保护性糖蛋白可能是适合治疗的靶点。 干预。此外，心肌和心脏成纤维细胞特异性低氧刺激的分泌蛋白 来自心肌缺血患者循环和升高的心脏成纤维细胞和肌细胞

The blockage of coronary arteries can result in a heart attack (acute myocardial infarction; Ml) and permanent loss of cardiac muscle tissue. The resulting destruction of the complex cardiac architecture, formation of scar tissue, and myocardial remodeling increases risk of death. The heart's initial response to injury is synchronous and involves, in part, the reciprocal interaction between cardiac fibroblasts and myocytes, the two primary cell types comprising the heart. Recent findings suggest that soluble proteins secreted from cardiac fibroblasts and myocytes, also called the secretome, can modulate the infarct microenvironment (extracellular matrix, ECM). It is the cell surface that not only acts as a physical barrier but senses of the local ECM microenvironment that initiates the intrinsic cellular protective mechanisms upon injury. Thus, the cell-environment interface is the main site of this interplay. We hypothesize that fibroblasts are the linchpin and their respond to injury launches wound healing while also promoting myocyte survival. Fibroblasts accomplish this by altering the ECM microenvironment surrounding myocytes, especially those present in the infarct border zone. Many of the proteins comprising cell-environment interface are glycosylated. In this proposal, we will use a number of innovative methods to target, enrich, quantify (relative and absolute) and characterize the glycoproteome of the cell-environment interface of myocytes and fibroblasts alone and in co-culture with and without injury induced by H2O2. This includes using a novel twist when co-culturing, in which the proteins from one cell type have a covalent quantitative labeled which provides a mass spectrometry friendly marker to distinguishing the cell origin of each protein. We hypothesize that cell-specific glycoproteome comprising the cell-environment interface is responsible to the intrinsic susceptibility to H2O2 of myocytes compared to fibroblasts (SA 1). Furthermore, that a subset of the fibroblast-specific secreted proteins which are elevated in co-culture induces myocyte-protection and this protective phenotype is enhanced by the action of when fibroblast, themselves are injured (SA-2). Finally, we hypothesize that glycoproteins present in the microenvironment which are exclusively elevated in response of H2O2 will be detected in the circulation of patients with myocardial injury (ischemia) prior to the elevation of cardiac troponins (gold standard markers for Ml). In summary, the protein complement of the cell-environment interface has not been fully elucidated for either cardiac fibroblasts or myocytes. This knowledge is fundamental to developing clinical approaches to protect the heart and potentially provide robust clinical biomarkers RELEVANCE (See instructions); This is the first systematic analysis of the glycoproteins which comprise the secretome and cell surface of myocytes and fibroblast, two major cell types of the heart, for which their interaction is synergetic and can results in myocyte protection. These protective glycoproteins could be targets suitable for therapeutic intervention. As well, the myocardial and cardiac fibroblast specific hypoxic stimulated secreted proteins from cardiac fibroblasts and myocytes that circulating and are elevated in patients with myocardial ischemia