The effect of a bioactive tissue-engineered sling in a rat of stress incontinence model

In this study, we attempt to examine the feasibility of the bioactive tissue-engineered sling by using muscle precursor cells (MPCs)-seeded Poly(ε-caprolactone) (PCL) nanofiber sheet in a rat model of stress urinary incontinence (SUI). In vitro, MPCs were cultured on a PCL nanofiber sheet for one week, where the MPCs-seeded PCL nanofiber sheet showed constant twitching contraction by electrical field stimulation in an organ bath. In vivo, MPCs-seeded PCL nanofiber sheet was placed under the female rat's urethra after pudendal nerve denervation (animal model of SUI). The leak point pressure (LPP) was evaluated with the vertical tilt table after the operation for four weeks. The resulting LPP of MPCs-seeded PCL nanofiber sheet group was observed to be significantly higher than the denervation-only group's. Furthermore, PKH-26-labeled MPCs were observed under the urethral sphincter by immunohistochemistry. These results indicated that, the MPCs-seeded PCL nanofiber sheet have not only provided support for the deficient sphincter, but also actively improved the sphincter's function overall. In conclusion, this bioactive tissue-engineered sling could be used as an ideal material for the treatment of SUI.