Vascular dysfunction caused by urethral injury often leads to delayed repair. Exosome from stem cell showed promise in tissue regeneration. But human induced pluripotent stem cell-derived exosomes (hiPSC-Exo) has not been reported the angiogenesis ability in urethral injury repair and their potential mechanisms. The exosome was extracted from hiPSCs. The in vivo and in vitro experiments were performed to investigate the effects of hiPSC-Exo on angiogenesis. The miRNA-seq bioinformatics, luciferase assay and related functional experiments were performed to determine potential mechanism. Exosome was extracted from hiPSCs by ultracentrifugation. Compared to the control group, hiPSC-Exo significantly promoted blood flow supply to the ischemic lower limbs of mice and rat model of urethral defects to accelerate injury repair. We found that hiPSC-Exo significantly enhanced the proliferation, migration, and tube formation ability of endothelial cells in vitro. MiRNA-seq analysis and experiments verified that miR-103a-3p was highly expressed in HUVEC treated with hiPSC-Exo and significantly enhanced the proliferation, migration, invasion, and angiogenesis effects. TGFBR3 was identified as a direct target of miR-103a-3p through bioinformatics, qPCR, and dual luciferase assays. Overexpression of TGFBR3 leaded to reduced proliferative, migrative and angiogenesis ability of HUVEC, but silence could promote HUVEC function. TGFBR3 could decrease VEGF expression and phosphorylation-based activation of FAK. This study indicated that hiPSC-Exo played a crucial role in promoting angiogenesis to accelerate urethral injury repair through the action of miR-103a-3p in exosome on the TGFBR3/VEGF/FAK signaling pathway in endothelial cells. This provides a new treatment strategy for hiPSC-Exo in the clinical treatment of urethral injury healing and elucidates its unique mechanism of action.
Sun et al. (Sat,) studied this question.