Exosomes Loaded With MiR-21 Promote Differentiation of Dental Pulp Stem Cells Into Endothelial Cells.

OBJECTIVES: This study utilized human umbilical vein endothelial cells (HUVECs) as vector cells to examine the impact of miR-21 on the vascular differentiation of Human dental pulp stem cells (hDPSCs) in recipient cells. MiR-21 was transfected into HUVECs to modulate the levels of miR-21 in exosomes and explore associated molecular signalling mechanisms. MATERIALS AND METHODS: Various groups of conditioned media were prepared to culture hDPSCs based on the differential expression of miR-21 in exosomes. Subsequently, cellular proliferation, migration, adhesion, and angiogenic capabilities were assessed. Target genes of miR-21 were validated via dual luciferase assay, along with the examination of downstream signalling pathways. RESULTS: Both HUVECs-exos and overexpression groups markedly enhanced the adhesion, proliferation, migration, and angiogenic abilities of hDPSCs. However, the overexpression group exhibited a more pronounced promotional effect compared to the HUVECs-exos group, while the inhibition group showed no statistically significant differences. The dual-luciferase reporter gene assay confirmed the targeting linkage between miR-21 and JAG1, indicating that changes in miR-21 levels in hDPSCs impacted the expression of the JAG1/NOTCH1/VEGF signalling pathway. CONCLUSION: HUVEC-derived exosomes with elevated miR-21 levels promote adhesion, proliferation, migration and in vitro capillary-like tube formation in hDPSCs. MiR-21 modulates hDPSCs' in vitro angiogenic phenotypes via targeting JAG1 and subsequently activating the JAG1/NOTCH1/VEGF signalling pathway.