Exosomes From LPS-stimulated hDPSCs Promote the Angiogenesis of HUVECs

Abstract

Background: Angiogenesis is fundamental to biomimetic pulp regeneration. Extracellular vesicles (EVs) derived from human dental pulp stem cells (hDPSCs) from patients with periodontitis were reported to have better angiogenic capabilities. However, the underlying regulatory mechanism remains unknown. As an important component of EVs, exosomes from hDPSCs were indicated to play a crucial role in multiple regeneration processes. In this study, the inflammatory factor lipopolysaccharide (LPS) was used to stimulate hDPSCs, and exosomes were extracted from these hDPSCs. The role of exosomes in the angiogenesis of Human Umbilical Vein Endothelial Cells (HUVECs) was examined, and the underlying mechanism was studied.Method: Exosomes were isolated from hDPSCs with or without LPS stimulation. The angiogenic capabilities of HUVECs were evaluated after coculture with exosomes derived from hDPSCs (hDPSC-EXOs) or exosomes derived from LPS-stimulated hDPSCs (LPS-hDPSC-EXOs). Tube formation and migration assays were conducted, and angiogenesis-related mRNA expression was detected. MicroRNA sequencing was performed to explore the microRNA profile of hDPSC-EXOs and LPS-hDPSC-EXOs. Gene Ontology (GO) analysis was used to study the functions of the predicted target genes. Kyoto Encyclopedia of Genes and Genomes (KEGG) pathway analysis was used to estimate the signaling pathways associated with the inflammation-induced angiogenesis process.Result: The release of hDPSC-EXOs increased after stimulation with LPS. Compared to endocytosis of hDPSC-EXOs, endocytosis of LPS-hDPSC-EXOs promoted the tube formation and migration of HUVECs. The mRNA expression levels of vascular endothelial growth factor (VEGF) and kinase-insert domain-containing receptor (KDR) in the LPS-hDPSC-EXOs group were significantly higher than those in the hDPSC-EXOs group. MicroRNA sequencing showed that 10 microRNAs were significantly changed in LPS-hDPSC-EXOs; of these microRNAs, 7 were increased, and 3 were decreased. Pathway analysis showed that the genes targeted by differentially expressed microRNAs were involved in multiple angiogenesis-related pathways.Conclusion: This study revealed that exosomes derived from inflammatory hDPSCs displayed a stronger effect on vascular regeneration. It’s the first time to explore the role of exosomal microRNA from hDPSCs in inflammation-induced angiogenesis. This finding sheds new light on the effect of inflammation-stimulated hDPSCs on tissue regeneration.