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

摘要 巨噬细胞在炎症、系统代谢、组织修复、宿主防御等方面发挥着关键作用。 微生物感染和肿瘤监测。新的证据表明，促炎症的巨噬细胞依赖于 糖酵解和脂肪酸合成对促炎基因的表达，同时对抗炎作用 巨噬细胞需要氧化磷酸化和脂肪酸氧化来表达抗炎基因， 这表明，细胞代谢的不同方面调节着巨噬细胞的激活和极化。 MicroRNAs(MiRNAs)是一类新的控制基因表达的非编码小RNA调节子。 许多miRNAs选择性地在免疫细胞中表达，并与免疫反应有关 宿主防御和自身免疫性疾病。最近的发现表明miRNAs参与了基本的 巨噬细胞通过调节细胞新陈代谢发挥作用。然而，目前还不清楚miRNAs如何调节细胞 巨噬细胞活化和炎症表型测定的代谢。 使用基于慢病毒的miRNA文库，可以减少miRNA过程中发生的不一致 在描述过程中，我们选择了调节巨噬细胞炎症反应的miRNAs 未被确定为新陈代谢和巨噬细胞激活的调节剂。我们的长期目标是揭示 MiRNAs在miRNAs与巨噬细胞代谢和表型功能关联中的作用 并将这一认识应用于炎症性疾病的治疗。MIR-22，其中一种 从筛选过程中筛选出的miRNA候选基因，调控着肿瘤坏死因子成员4-1BBL的表达 和葡萄糖转运蛋白1(Glut1)在巨噬细胞激活过程中的糖酵解中。然而，它并不是 明确miR-22在炎性巨噬细胞活化中如何调节4-1BBL和Glut1的表达 疾病。为了研究这一点，我们假设miR-22调节4-1BBL和Glut1的表达 巨噬细胞持续炎症的调节，巨噬细胞调节失调参与了巨噬细胞的病理变化 银屑病。我们将研究miR-22依赖的巨噬细胞代谢调节机制和 利用生物化学和分子生物学方法确定表型，如分析 信号通路和测量细胞代谢(目标1)，并研究miR-22在炎症中的作用 咪喹莫特诱导的银屑病样皮肤小鼠模型的疾病及其治疗潜力 炎症以测试miR-22应用是否可以减轻银屑病的病理(目标2)。 了解miRNA在调节巨噬细胞代谢中的重要性将阐明新的 巨噬细胞活化的调控机制及表型确定在肿瘤发生发展中的作用 炎症性疾病。我们对miRNAs以前无人参与的功能和调控机制的探索 将提供关于先天免疫的新的翻译见解 炎症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.