Exosomes derived from human amniotic mesenchymal stem cells promotes angiogenesis in hUVECs by delivering novel miRNA...

To investigate the effect and mechanism of exosomes derived from human amniotic mesenchymal stem cells (hAMSC-Exos) promoting angiogenesis.

HAMSC-Exos were isolated using ultracentrifugation and characterized by transmission electron microscopy, NTA, and Western blot. The uptake of hAMSC-Exos by hUVECs was analyzed using PKH-26 labeling, and the effect of hAMSC-Exos on angiogenesis was analyzed in human umbilical vein endothelial cells hUVECs by cell viability assay, Transwell migration assay, Matrigel tube formation assay, and Matrigel plug assays in nude mice. Bioinformatics methods were used to analyze miRNA high-throughput sequencing data of hAMSC-Exos, and RT-qPCR was used to validate the novel miRNAs. HAMSC-Exos with high and low N-194 expression were obtained by transfection, respectively. Target genes were predicted using TargetScan, and the mRNA and protein levels of potential target genes were analyzed by RT-qPCR and Western blot after N-194 mimics transfection. Interaction between miRNAs and target genes was detected using the dual-luciferase reporter assay. Target genes were overexpressed in hUVECs by transfection. The roles of target genes in the influence of N-194 on cell function were determined by analyzing angiogenesis.

The extracted hAMSC-Exos showed saucer-shaped under transmission electron microscopy, and the NTA results showed the particle size of 115.6 ± 38.6 nm. The positive expression of CD9, CD63, and CD81 were verified using Western blot. The treatment of hUVECs with hAMSC-Exos significantly increased cell proliferation, migration, and angiogenesis. HAMSC-Exos contained the novel miRNAs N-194, N-314, N-19, N-393, and N-481, and the expression of N-194 was higher. The Exos derived from hAMSCs which were transfected with FAM-N-194 mimics were able to deliver FAM-N-194 mimics to hUVECs. The hAMSC-Exos with high N-194 significantly promoted angiogenesis in hUVECs. N-194 mimics transfection significantly reduced mRNA and protein levels of potential target gene ING5, and N-194 mimics significantly reduced the luciferase activities expressed by wild-type reporter gene vectors for ING5. The ING5 overexpression significantly reduced the angiogenic capacity of hUVECs. ING5 overexpression suppressed the expression of HSP27 and PLCG2.

HAMSC-Exos promotes angiogenesis in hUVECs by delivering novel miRNA N-194 which targets ING5.