mir219 in oligodendrocyte differentiation and myelination

Young and environmentally enriched exosomes deliver functional miR-219 that impacts oligodendrocyte differentiation and myelination. Schematic illustration of the involvement of miR-219 in oligodendrocyte differentiation. Upon exposure to nutritive exosomes, neural stem cells preferentially enter the oligodendrocyte lineage due to the inhibition of the proneurogenic factor NeuroD1. miR-219 also suppresses expression of a number of other factors that inhibit OPC differentiation, such as PDGFRα, a receptor for a mitogenic factor that promotes proliferation and prohibits differentiation. Finally, miR-219 decreases levels of ELOVL7, a regulator of lipid metabolism whose over-activity could lead to demyelination.

青春期且富含环境因素的细胞外囊泡可输送具有功能的miR-219，该miR-219影响少突胶质细胞的分化和髓鞘形成。以下为miR-219在少突胶质细胞分化过程中的作用示意图。在暴露于营养性细胞外囊泡后，神经干细胞倾向于进入少突胶质细胞谱系，这得益于对神经发生因子NeuroD1的抑制。miR-219还抑制了多种抑制少突胶质细胞分化的因子的表达，例如PDGFRα，其为促进增殖并阻止分化的原癌基因因子受体的表达。最终，miR-219降低了ELOVL7的水平，ELOVL7是一种调节脂质代谢的因子，其过度活跃可能导致脱髓鞘病变。