Novel MPO-derived plasma lipids as predictors of major adverse coronary events

描述(申请人提供)：每年有50多万美国公民因冠状动脉疾病而猝死。开发预测重大不良冠状动脉事件风险增加的生物标记物是美国一项主要的公共卫生需求。血浆髓过氧化物酶(MPO)水平升高已被证明是急性冠脉综合征患者冠状动脉事件风险增加的预测因子。中性粒细胞释放MPO先于心肌损伤，已有研究表明，MPO活性可能在一定程度上介导了不良的冠状动脉事件。因此，与血浆MPO水平相比，血浆MPO产生的氧化产物水平可能更好地预测不良冠状动脉事件。我们发现1-氯代脂肪醛(1-ClFALD)是一种新的MPO生成的脂质氧化产物。在过去的一年里，我们发现1-氯脂肪酸(1-ClFA)和1-氯脂肪醇(1-ClFOH)是中性粒细胞释放的1-ClFALD的稳定代谢产物，也存在于人的血浆中。因此，这项建议的具体目的是检验这样一种假设，即血浆1-ClFA和1-ClFOH水平预测冠心病患者发生主要不良冠状动脉事件的风险增加。克利夫兰诊所基金会的一项名为Genebank的研究将提供一个广泛的临床数据库和人类血浆样本储存库，用于这些研究。接受诊断性心导管置入术的受试者的大量临床表型数据可用于本研究的所有受试者。有完整的病史、实验室、血管造影和结果数据，受试者同意使用这些标本和匿名化的临床数据，以支持与心血管疾病相关的生化研究工作。病例队列设计将使我们能够使用相同的对照人群来评估多种结果。病例定义将包括遭受非致命性心肌梗死、中风或死亡的受试者。对照将从Genebank登记的年龄和性别匹配的合格受试者中随机抽样，证明没有心血管疾病的间歇性病史。在圣路易斯大学，血浆1-ClFA将在使用电喷雾电离的三重四极仪器上用LC-MS进行定量。将血浆中的1-ClFOH衍生化为五氟苯甲酸酯后，用负离子化学电离的GC-MS法定量。每一种分析物都将通过与合成制备的氢化内标物进行比较来进行量化。这些新生物标志物的水平将与以前在这些标本中定量的C-反应蛋白、MPO、氯酪氨酸、硝基酪氨酸和肌钙蛋白T等其他生物标志物的水平进行比较。Genebank中收集的这些人类样本的可用性提供了一个非同寻常的机会，可以在一组有重点和明确定义的心脏病患者的血浆中识别这些新的MPO催化的氧化产物作为新的生物标记物。此外，这项研究将首次直接测量全身性MPO催化的脂质氧化，并评估其与心血管疾病的潜在临床相关性。与公共健康相关：约有1300万美国公民患有冠状动脉疾病，这是导致男性和女性死亡的主要原因。在拟议的研究中，我们将检验这样一种假设，即血浆中MPO产生的新型脂质氧化产物水平可以预测主要的不良冠状动脉事件。确定这些新的脂质氧化产物作为未来主要不良冠状动脉事件的预测因子，可能会显著影响冠心病患者的护理和预后。

DESCRIPTION (provided by applicant): Coronary artery disease is responsible for the sudden death of over 500,000 U.S. citizens per year. The development of biomarkers that predict increased risk of major adverse coronary events is a major public health need in the United States. Elevated plasma myeloperoxidase (MPO) levels have been shown to be a predictor of increased risk of coronary events in patients with acute coronary syndromes. MPO release from neutrophils precedes myocardial injury, and it has been suggested that MPO activity may mediate, in part, adverse coronary events. Accordingly, in comparison to plasma MPO levels, plasma levels of MPO-generated oxidation products may be better predictors of adverse coronary events. We have discovered 1-chloro-fatty aldehyde (1- ClFALD) as a novel MPO-generated lipid oxidation product. In the past year, we have revealed that 1-chloro- fatty acid (1-ClFA) and 1-chloro-fatty alcohol (1-ClFOH) are stable metabolites of 1-ClFALD that are released from neutrophils and are also present in human plasma. Accordingly, the specific aim of this proposal is to test the hypothesis that plasma levels of 1-ClFA and 1-ClFOH predict increased risk of major adverse coronary events in patients with coronary artery disease. An extensive clinical database and repository of human plasma specimens from a study called Genebank at the Cleveland Clinic Foundation will be available for these studies. Extensive clinical phenotypic data from subjects undergoing diagnostic cardiac catheterization are available for all subjects enrolled in this study. Complete medical history, laboratory, angiographic and outcomes data are available, and subjects have provided consent for use of these specimens and anonymonized clinical data to support biochemical research efforts related to cardiovascular disease. A case-cohort design will allow us to evaluate multiple outcomes using the same control population. The case definition will include subjects that suffered non-fatal myocardial infarction, stroke or death. Controls will be drawn from a random sample of age and gender-matched eligible subjects from the Genebank registry demonstrating no inter- vening history of cardiovascular disease. At Saint Louis University, plasma 1-ClFA will be quantified by LC-MS on a triple quadrupole instrument using electrospray ionization. Plasma 1-ClFOH will be quantified using GC- MS with negative ion-chemical ionization following derivatization to its pentafluorobenzoyl ester. Each analyte will be quantified by comparisons to synthetically-prepared deuterated internal standards. Comparisons will be made between levels of these new biomarkers to that of other biomarkers including C-reactive protein, MPO, chlorotyrosine, nitrotyrosine and troponin T that have previously been quantified in these specimens. The availability of these collected human samples in Genebank provides an extraordinary opportunity to identify these novel MPO-catalyzed oxidation products in the plasma of a focused and well-defined group of heart patients as novel biomarkers. Furthermore, this study will allow a direct measure of systemic MPO-catalyzed lipid oxidation for the first time and evaluation of its potential clinical relevance to cardiovascular disease. PUBLIC HEALTH RELEVANCE: About 13 million U.S. citizens have coronary artery disease, and it is the leading cause of death among both men and women. In the proposed studies, we will test the hypothesis that plasma levels of novel MPO-generated lipid oxidation products predict major adverse coronary events. Identifying these novel lipid oxidation products as predictors of future major adverse coronary events has the potential to significantly impact care and outcomes of patients with coronary artery disease.