Department of Ophthalmology and Visual Sciences.
Neuroscience Graduate Program, Division of Biology and Biomedical Sciences.
JCI Insight. 2018 Apr 5;3(7). doi: 10.1172/jci.insight.120157.
Macrophage aging is pathogenic in diseases of the elderly, including age-related macular degeneration (AMD), a leading cause of blindness in older adults. However, the role of microRNAs, which modulate immune processes, in regulating macrophage dysfunction and thereby promoting age-associated diseases is underexplored. Here, we report that microRNA-150 (miR-150) coordinates transcriptomic changes in aged murine macrophages, especially those associated with aberrant lipid trafficking and metabolism in AMD pathogenesis. Molecular profiling confirmed that aged murine macrophages exhibit dysregulated ceramide and phospholipid profiles compared with young macrophages. Of translational relevance, upregulation of miR-150 in human peripheral blood mononuclear cells was also significantly associated with increased odds of AMD, even after controlling for age. Mechanistically, miR-150 directly targets stearoyl-CoA desaturase-2, which coordinates macrophage-mediated inflammation and pathologic angiogenesis, as seen in AMD, in a VEGF-independent manner. Together, our results implicate miR-150 as pathogenic in AMD and provide potentially novel molecular insights into diseases of aging.
巨噬细胞衰老在老年疾病中具有致病性,包括年龄相关性黄斑变性(AMD),这是老年人失明的主要原因。然而,调节免疫过程的 microRNAs 在调节巨噬细胞功能障碍并从而促进与年龄相关的疾病方面的作用尚未得到充分探索。在这里,我们报告 microRNA-150(miR-150)协调衰老的鼠巨噬细胞中的转录组变化,特别是那些与 AMD 发病机制中异常脂质转运和代谢相关的变化。分子分析证实,与年轻巨噬细胞相比,衰老的鼠巨噬细胞表现出神经酰胺和磷脂谱的失调。具有转化相关性的是,miR-150 在人外周血单核细胞中的上调与 AMD 的发生几率增加显著相关,即使在控制年龄后也是如此。从机制上讲,miR-150 直接靶向硬脂酰辅酶 A 去饱和酶-2,该酶以 VEGF 非依赖性方式协调巨噬细胞介导的炎症和 AMD 中的病理性血管生成。总之,我们的结果表明 miR-150 在 AMD 中具有致病性,并为衰老相关疾病提供了潜在的新分子见解。