Mesenchymal stem cells-derived extracellular vesicles, via miR-210, improve infarcted cardiac function by promotion of angiogenesis.

Mesenchymal stem cells (MSCs) exert therapeutic effect on treating acute myocardial infarction. Recent evidence showed that paracrine function rather than direct differentiation predominately contributes to the beneficial effects of MSCs, but how the paracrine factors function are not fully elucidated. In the present study, we tested if extracellular vesicles (EVs) secreted by MSC promotes angiogenesis in infracted heart via microRNAs. Immunostaining of CD31 and matrigel plug assay were performed to detect angiogenesis in a mouse myocardial infarction (MI) model. The cardiac function and structure was examined with echocardiographic analysis. Capillary-like tube formation, migration and proliferation of human umbilical vein endothelial cells (HUVECs) were determined. As a result, MSC-EVs significantly improved angiogenesis and cardiac function in post-MI heart. MSC-EVs increased the proliferation, migration and tube formation capacity of HUVECs. MicroRNA (miR)-210 was found to be enriched in MSC-EVs. The EVs collected from MSCs with miR-210 silence largely lost the pro-angiogenic effect both in-vitro and in-vivo. The miR-210 target gene Efna3, which plays a role in angiogenesis, was down-regulated by MSC-EVs treatment in HUVECs. In conclusion, MSC-EVs are sufficient to improve angiogenesis and exert therapeutic effect on MI, its pro- angiogenesis effect might be associated with a miR-210-Efna3 dependent mechanism. This article is part of a Special Issue entitled: Genetic and epigenetic control of heart failure - edited by Jun Ren & Megan Yingmei Zhang.