Regulation of lipid metabolism by miRNAs

miRNA是一种小的调控RNA分子，通过与其靶mRNA结合并促进mRNA降解或抑制翻译来调节基因表达。 miRNA还与外泌体一起在血浆中循环。 在过去的一年中，我们发现miRNA也可以与脂蛋白结合（参考文献2）。 此外，我们发现miRNAs的含量可以随血脂异常而变化，这表明它们可能作为心血管疾病的生物标志物。已经显示通过细胞摄取外来体递送miRNA调节基因表达。 使用含有miRNAs的重组HDL，我们能够通过SR-BI受体将miRNAs递送至细胞并改变其靶基因的表达，这表明通过脂蛋白递送内源性miRNAs可能改变基因表达。 未来的研究将旨在了解细胞外和细胞内miRNA对脂质代谢的作用。

miRNAs are small regulatory RNA molecules the modulate gene expression by binding to their target mRNAs and either promoting mRNA degradation or inhibiting translation. miRNAs also circulate in plasma in association with exosomes. In the past year, we found that miRNAs can also associate with lipoproteins (ref. 2). Furthermore, we found that the content of miRNAs can vary with dyslipidemias, indicating that they can potentially serve as biomarkers for cardiovascular disease. Delivery of miRNAs by cellular uptake of exosomes has been shown to modulate gene expression. Using reconstituted HDL containing miRNAs, we were able to deliver miRNAs to cells via the SR-BI receptor and alter the expression of their target genes, which indicates that delivery of endogenous miRNAs by lipoproteins can potentially alter gene expression. Future studies will be aimed at understanding the role of both extracellular and intracellular miRNAs on lipid metabolism.