Regulatory effect of exosomes secreted by vaginal wall fibroblasts on angiogenesis in patients with stress urinary incontinence

Objective Exosomes are considered to mediate intercellular communication by delivering biomolecules like mRNA, miRNA into recipient cells. The purpose of this study was to evaluate the effects of exosomes secreted by fibroblasts from women with stress urinary incontinence (SUI-EXO) on endothelial cells angiogenesis. Methods Primary fibroblasts were acquired from periurethral vaginal wall tissues and exosomes were prepared by ultracentrifugation of fibroblasts cells conditioned medium. The expression levels of pro-angiogenic and anti-angiogenic genes were assessed using qRT-PCR analysis. Migration of endothelial cells was measured by transwell assay, and the effects of SUI-EXO on angiogenesis were evaluated by performing a tube formation assay in vitro. Results SUI-EXO was successfully isolated from fibroblasts cells conditional medium and transferred to endothelial cells efficiently. When the endothelial cells were treated with SUI-EXO, the expression levels of pro-angiogenic genes in fibroblasts were downregulated, and the expression levels of anti-angiogenic genes were upregulated significantly (P<0.01). Endothelial cells exhibited a decreased migratory capacity after treatment with SUI-EXO compared to exosomes from health women (64.6±8.7 vs 114.5±14.2,P<0.01), and tube formation of endothelial cells was also significantly inhibited in the SUI-EXO treated group as determined by the increase of the tube length (87.6±13.3 vs 168.5±28.3,P<0.01). Conclusion This study suggests that SUI-EXO plays related roles in regulating endothelial cells angiogenesis and SUI-EXO maybe involve in the pathogenesis of SUI. Key words: SUI; Endothelial cells; Exosome; Angiogenesis