Effect of Heme on mRNA and miRNA Profile

血红素对 mRNA 和 miRNA 谱的影响

• 批准号: 9096937
• 负责人: HERBERT L BONKOVSKY
• 金额: $ 32.6万
• 依托单位: WINSTON-SALEM STATE UNIVERSITY
• 依托单位国家: 美国
• 财政年份: 2013
• 资助国家: 美国
• 起止时间: 2013-02-01 至 2016-12-31
• 项目状态: 已结题
• 来源: https://reporter.nih.gov/project-details/9096937
• 关键词: Effect; Heme; mRNA; miRNA; Profile

Heme [iron protoporphyrin] is a primordial macrocycle upon which nearly all life on earth depends. It has manifold known functions and diverse properties. The importance of a normal pathway and regulation of heme metabolism is underscored by the seriousness of diseases in which there are defects in heme homeostasis. For example, the porphyrias are a group of diseases in which there are defects in normal heme synthesis, due mainly to inborn errors of metabolism that produce deficient activities of the enzymes of normal porphyrin and heme synthesis. Genes and their products of particular importance in heme metabolism are ALA synthase 1 [ALAS1] and heme oxygenase 1 [HMOX1], respectively, the rate-controlling enzymes of heme synthesis and catabolism. Hydroxymethylbilane synthase [HMBS], the third enzyme of the heme biosynthetic pathway, is deficient in acute intermittent porphyria, the most severe of the acute porphyrias. Recently, we reported important novel effects of miRNAs-122, -196, and -let 7 on expression of HMOX1 and its key repressor BACH1, and we recently discovered new and heretofore unexpected roles of proteasomal and other protease pathways that regulate levels of ALAS1, BACH1, and HMOX1. We also have discovered changes caused by heme excess vs heme deficiency on reciprocal expression of miRNAs and mRNAs in human hepatocytes. Heme, which is the treatment of choice for acute porphyric attacks and for their prevention, may have deleterious effects on the liver and other tissues and organs, especially with repeated use. Our recent microarray results in human Huh-7 cells have unveiled novel effects of heme excess vs heme deficiency on several genes and pathways. It is important now to assess the potential physiological importance of alterations in miRNA and mRNA profiles in in vitro models and whether and to what extent similar changes occur in vivo, in animal models of AIP and in humans with acute porphyrias. We hypothesize that heme and other metalloporphyrins regulate ALAS1, HMBS and HMOX1 expression by altering selected microRNAs and mRNA profiles Our specific aims are as follows: Aim #1: To delineate effects and mechanisms whereby selected microRNAs modulate expression of ALAS1, HMBS, and HMOX1 and/or their key regulators in human hepatocytes. Aim #2 To characterize the effects of selected, physiologically relevant doses of heme on the livers, kidneys, spleens, and bone marrows of mice with mutations that resemble those seen in human AIP and on peripheral blood mononuclear cells of patients with AIP who are receiving heme as therapy. Results of these studies will provide important new insights into the manifold and critical functions of heme in health and disease, and in our understanding at both the basic and clinical level.

血红素[铁原卟啉]是一种原始的大环化合物，地球上几乎所有的生命都依赖于它。它有 多种已知功能和不同的属性。血红素的正常途径和调节的重要性 在血红素体内平衡存在缺陷的疾病的严重性强调了代谢的重要性。 例如，卟啉症是一组疾病，其中正常血红素合成存在缺陷，由于 主要是先天性代谢缺陷，其产生正常卟啉的酶的活性不足， 血红素合成在血红素代谢中特别重要的基因及其产物是ALA合成酶1 [ALAS 1]和血红素加氧酶1 [HMOX 1]，分别是血红素合成的速率控制酶， 猫羟甲基胆烷合酶[HMBS]是血红素生物合成途径的第三种酶， 缺乏急性间歇性卟啉症，最严重的急性卟啉症。最近，我们报道了 miRNAs-122、-196和-let 7对HMOX 1及其关键阻遏物表达的重要新作用 BACH 1，我们最近发现了蛋白酶体和其他蛋白酶的新的和迄今为止意想不到的作用 调节ALAS 1、BACH 1和HMOX 1水平的途径。我们还发现了 血红素过量与血红素缺乏对人肝细胞中miRNAs和mRNAs相互表达影响 血红素，这是治疗急性卟啉攻击和预防的选择，可能有 对肝脏和其他组织和器官的有害作用，特别是重复使用。我们最近 人类Huh-7细胞的微阵列结果揭示了血红素过量与血红素缺乏对 几个基因和途径。现在重要的是评估改变的潜在生理重要性 在体外模型中的miRNA和mRNA谱以及是否以及在何种程度上在体内发生类似的变化， 在AIP动物模型和急性卟啉症患者中。我们假设血红素和其他 金属卟啉通过改变选定的microRNA调节ALAS 1、HMBS和HMOX 1的表达， mRNA谱我们的具体目标如下：目标#1：描述作用和机制 从而选择的microRNA调节ALAS 1、HMBS和HMOX 1的表达和/或它们的关键基因 人类肝细胞中的调节因子。目的#2描述选择的生理学、 相关剂量的血红素对突变小鼠的肝脏、肾脏、脾脏和骨髓的影响， 类似于在人AIP和AIP患者外周血单核细胞中观察到的那些 接受血红素治疗的人这些研究的结果将提供重要的新见解， 血红素在健康和疾病中的多种重要功能，以及我们对血红素的基本和 临床水平。