Role of miRNA for the regulation of macrophage metabolism and phenotype determination in inflammatory disease

摘要 巨噬细胞在炎症、全身代谢、组织修复、宿主防御等方面发挥着重要作用， 微生物感染和肿瘤监测。新出现的证据表明，促炎性巨噬细胞依赖于 对糖酵解和脂肪酸合成的促炎基因的表达，而抗炎 巨噬细胞需要氧化磷酸化和脂肪酸氧化来表达抗炎基因， 表明细胞代谢的不同方面调节巨噬细胞活化和极化。 microRNAs（miRNAs）是一类新型的调控基因表达的非编码小RNA调节因子。 许多miRNAs在免疫细胞中选择性表达，并与免疫应答有关， 宿主防御和自身免疫性疾病。最近的研究结果表明，miRNAs参与了基础的 巨噬细胞通过调节细胞代谢发挥功能。然而，目前尚不清楚miRNAs是如何调节细胞凋亡的。 用于巨噬细胞活化和炎性表型测定的代谢。 使用基于慢病毒的miRNA文库，可以减少miRNA表达过程中发生的不一致性。 在分析过程中，我们选择了调节巨噬细胞炎症反应的miRNA， 未被鉴定为代谢和巨噬细胞活化的调节剂。我们的长期目标是揭示 miRNAs在巨噬细胞代谢和表型中的作用 确定，并将该理解应用于炎性疾病的治疗。miR-22是一种 从筛选过程中获得的miRNA候选物调节TNF家族成员4-1BBL的表达， 超家族和葡萄糖转运蛋白1（Glut 1）在巨噬细胞活化过程中糖酵解中的作用。但不 明确miR-22如何调节炎症性巨噬细胞活化中4-1BBL和Glut 1的表达， 疾病为了研究这一点，我们假设miR-22调节4-1BBL和Glut 1的表达， 调节巨噬细胞中的持续炎症，其调节异常有助于 银屑病我们将研究miR-22依赖性调节巨噬细胞代谢的机制， 表型测定通过使用生物化学和分子生物学方法，如分析 信号通路和测量细胞代谢（目的1），并研究miR-22在炎症反应中的作用。 使用咪喹莫特诱导的银屑病样皮肤的小鼠模型的疾病及其治疗潜力 炎症，以测试miR-22施用是否可以减轻银肩病的病理（目的2）。 了解miRNA在调节巨噬细胞代谢中的重要性将阐明新的 巨噬细胞活化和表型决定的调节机制， 炎症性疾病。我们对miRNAs以前未被关注的功能和控制机制的探索 在调节细胞代谢中的作用将为先天免疫提供新的翻译见解， 炎性疾病的发展和治疗。

ABSTRACT Macrophages play a critical role in inflammation, systemic metabolism, tissue repair, host defense to microbial infection, and tumor surveillance. Emerging evidence shows that pro-inflammatory macrophages rely on glycolysis and fatty acid synthesis for the expression of pro-inflammatory genes, while anti-inflammatory macrophages require oxidative phosphorylation and fatty acid oxidation for anti-inflammation gene expression, suggesting that distinct aspects of cell metabolism regulate macrophage activation and polarization. MicroRNAs (miRNAs) are a novel class of small noncoding RNA regulators that control gene expression. Many miRNAs are selectively expressed in immune cells, and have been implicated in immune responses in host defense and autoimmune disease. Recent findings indicate that miRNAs are involved in fundamental macrophage functions by regulating cell metabolism. However, it is not clear how miRNAs regulate cell metabolism for macrophage activation and inflammatory phenotype determination. Using a lentivirus-based miRNA library that can reduce the inconsistency that occurs during the miRNA profiling process, we selected miRNAs that regulate inflammatory responses in macrophages and that have not been identified as regulators of metabolism and macrophage activation. Our long-term goal is revealing the role of miRNAs for the functional association of miRNAs with macrophage metabolism and phenotype determination, and applying that understanding for the treatment of inflammatory disease. miR-22, one of the miRNA candidates from the screening process, regulates the expression of 4-1BBL, a member of the TNF superfamily, and glucose transporter 1 (Glut1) in glycolysis during macrophage activation. However, it is not clear how miR-22 regulates the expression of 4-1BBL and Glut1 in macrophage activation in inflammatory disease. To investigate this, we hypothesize that miR-22 regulates the expression of 4-1BBL and Glut1 for the regulation of sustained inflammation in macrophages, dysregulation of which contributes to the pathology of psoriasis. We will examine the mechanism of miR-22-dependent regulation of macrophage metabolism and phenotype determination by using biochemistry and molecular biology approaches such as analysis of the signaling pathways and measuring cell metabolism (Aim 1) and study the role of miR-22 in inflammatory diseases and its therapeutic potential using a mouse model of imiquimod-induced psoriasis-like skin inflammation to test whether miR-22 administration can alleviate the pathology of psoriasis (Aim 2). Understanding the importance of miRNA in the regulation of macrophage metabolism will elucidate novel regulatory mechanisms in macrophage activation and phenotype determination in the development of inflammatory diseases. Our exploration of a previously unattended function and control mechanism of miRNAs in the regulation of cell metabolism will provide new translational insights about innate immunity in inflammatory disease development and treatment.