Functional Impact of HDL transport of miRNA in rheumatoid arthritis

 描述(申请人提供)：类风湿性关节炎(RA)是一种炎症性自身免疫性疾病，与心血管风险增加两倍相关，独立于脂蛋白浓度和其他传统风险因素。一些证据表明，高密度脂蛋白(HDL)功能受损而不是浓度变化会增加心血管风险；在RA中，高密度脂蛋白胆固醇与高炎症或氧化应激环境下心血管风险的增加矛盾地相关。高密度脂蛋白功能受损的机制尚不清楚，但最近发现高密度脂蛋白在细胞之间运输microRNAs(MiRNAs)提供了一种新的机制，高密度脂蛋白可以以高度特异的方式调节细胞间的通讯。MiRNAs是一种小的非编码RNA，是免疫和炎症的强大基因调节器。例如，我们发现高密度脂蛋白将miRNAs转运到内皮细胞，改变黏附分子的表达。关于RA中高密度脂蛋白的miRNA货物，目前尚不清楚，这是一种潜在的机制，通过这种机制，一个部位的炎症可能会产生远距离的有害影响。最重要的假设是，在RA中，一种改变的高密度脂蛋白-miRNA货物被运送到对动脉粥样硬化的发展至关重要的细胞，导致细胞反应改变，为RA患者增加心血管风险提供了机制。在初步数据的基础上，AIM 1将通过对RA患者和对照组纯化的高密度脂蛋白进行小RNA测序，进一步确定类风湿关节炎中的高密度脂蛋白-miRNA货物。这些发现将有助于选择与类风湿关节炎炎症和内皮功能最密切相关的高密度脂蛋白-miRNAs。在目标2中，巨噬细胞将用维甲酸处理，并控制高密度脂蛋白。不同的miRNA转移和由此导致的促炎细胞因子表达的变化将被量化。在目标3中，内皮细胞将用维甲酸处理，并对照高密度脂蛋白。MiRNA的差异转移以及由此导致的黏附分子表达和一氧化氮产生的变化将被量化。这种通过高密度脂蛋白-miRNA传递细胞间通讯的新机制将为RA降低心血管风险提供新的治疗途径。申请者Ormseth博士在临床和翻译研究方面有很强的背景，并致力于风湿病的学术生涯。在范德比尔特获得临床风湿学奖学金后，她获得了临床调查理学硕士学位，并由T-32拨款资助完成了另外两年的研究奖学金。她的职业目标是成为与炎症性风湿性疾病患者加速动脉粥样硬化的机制和治疗有关的脂质和miRNA生物学领域的独立研究员。在系统生物学和脂蛋白新陈代谢等主题上的额外指导研究时间和培训将有助于扩大她的实验室和与她的职业道路相关的生物信息学技能。范德比尔特大学提供了一个特殊的发展环境。亮点是纽曼协会，它寻求为年轻调查人员提供独立的装备，核心设施，如采用最先进的RNAseq技术的Vantage，以及该大学对支持年轻调查人员的坚定承诺。医学部和风湿科支持奥姆塞斯博士的计划。她的导师斯坦博士、林顿博士和维克斯博士都是国际知名的，拥有成功学员的记录，并拥有必要的资源来培训她和发展她的事业。Ormseth博士的创新研究建议，加上出色的指导和卓越的环境，将帮助她在独立R01资助方面具有竞争力。

 DESCRIPTION (provided by applicant): Rheumatoid arthritis (RA) is an inflammatory autoimmune disease associated with a two-fold increased cardiovascular risk independent of lipoprotein concentrations and other traditional risk factors. Several lines of evidence suggest that impaired high-density lipoprotein (HDL) function rather than altered concentrations contributes to increased cardiovascular risk; in RA high HDL cholesterol is associated paradoxically with increased cardiovascular risk in the setting of high inflammation or oxidative stress. Mechanisms underlying impaired HDL function are unclear, but a recent discovery that HDL transports microRNAs (miRNAs) between cells provides a novel mechanism by which HDL can regulate intercellular communication in a highly specific manner. miRNAs are small non-coding RNAs that are powerful gene regulators of immunity and inflammation. For example, we found that HDL transports miRNAs to endothelial cells altering adhesion molecule expression. Nothing is known about miRNA cargo of HDL in RA, a potential mechanism whereby inflammation at one site may have distant deleterious effects. The overarching hypothesis is that in RA an altered HDL-miRNA cargo is delivered to cells key to the development of atherosclerosis leading to altered cellular responses providing a mechanism for increased CV risk in patients with RA. Building on preliminary data, Aim 1 will further define HDL-miRNA cargo in RA by sequencing small RNAs from purified HDL from patients with RA and controls. These findings will help select those HDL-miRNAs most closely associated with inflammation and endothelial function in RA. In Aim 2, macrophages will be treated with RA and control HDL. The differential miRNA transfer and resultant change in pro-inflammatory cytokine expression will be quantified. In Aim 3, endothelial cells will be treated with RA and control HDL. The differential miRNA transfer and resultant change in adhesion molecule expression and nitric oxide production will be quantified. This novel mechanism of intercellular communication by HDL-miRNA delivery will offer new avenues of therapeutics for RA to decrease cardiovascular risk. The applicant, Dr. Ormseth, has a strong background in clinical and translational research and is committed to an academic career in rheumatology. Following her clinical rheumatology fellowship at Vanderbilt, she obtained a Master of Science in Clinical Investigation degree and completed an additional two year research fellowship, funded by a T-32 grant. Her career goal is to become an independent investigator in the area of lipid and miRNA biology pertaining to mechanisms and treatment of accelerated atherosclerosis in patients with inflammatory rheumatic diseases. Additional mentored research time and training in topics such as systems biology and lipoprotein metabolism will help expand her laboratory and bioinformatics skills relevant to her career path. Vanderbilt University provides an exceptional environment in which to develop. Highlights are the Newman Society, which seeks to equip young investigators for independence, core facilities like VANTAGE with state- of-the-art RNAseq technology, and the deep commitment of the University to support young investigators. The Department of Medicine and Division of Rheumatology support Dr. Ormseth's plans. Her mentors, Drs. Stein, Linton, and Vickers, are internationally recognized, have track records of successful mentees, and have the necessary resources to train her and develop her career. Dr. Ormseth's innovative research proposal along with excellent mentoring and an outstanding environment will together help her to be competitive for independent R01 funding.