Exosome-derived miR-5p-72106_14 in vascular endothelial cells regulates fate determination of BMSCs.

Vascular endothelial cells have recently been shown to be associated with osteogenic activity. However, the mechanism of vascular endothelial cells promoting osteogenesis is unclear. Here, we found that exosomes secreted from human microvascular endothelial cells (HMEC-1) promoted osteogenic differentiation of bone marrow mesenchymal stem cells (BMSCs) and inhibited adipogenic differentiation. Aged and ovariectomy mice treated with exosomes showed increased bone formation and decreased lipid accumulation in the bone marrow cavity. Additionally, we screened out novel exosomal miR-5p-72106_14 by miRNA-seq and confirmed that miR-5p-72106_14 promoted osteogenic differentiation and inhibited adipogenic differentiation of BMSCs by inhibiting STAT1. Our results suggest that vascular endothelial cell-derived exosomes are involved in BMSC differentiation and exosomal miR-5p-72106_14 is a major factor in regulating fate determination of BMSCs. • HMEC-Exos promoted osteoblast and suppressed adipocyte differentiation of BMSCs. • Exosomal-miR-5p-72106_14 was newly defined and has not been reported before. • Exosomal-miR-5p-72106_14 regulated differentiation of BMSCs. • HMEC-EXOs treatment plays an important role in balancing bone homeostasis. [ABSTRACT FROM AUTHOR]