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Objective: To determine the outcomes and mechanisms of delayed low-intensity extracorporeal shock wave therapy (Li-ESWT) in a rat model of irreversible stress urinary incontinence (SUI)., Materials and Methods: Twenty-four female Sprague-Dawley rats were randomly assigned into 3 groups: sham control, vaginal balloon dilation + β-aminopropionitrile (BAPN; SUI group), and vaginal balloon dilation + BAPN + treatment with Li-ESWT (SUI-Li-ESWT group). An irreversible SUI model was developed by inhibiting the urethral structural recovery with BAPN daily for 5 weeks. Thereafter, in the SUI-Li-ESWT group, Li-ESWT was administered twice per week for 2 weeks. After a 1-week washout, all 24 rats were evaluated with functional and histologic studies at 17 weeks of age. Endogenous progenitor cells were detected via the EdU-labeling method., Results: Functional analysis with leak point pressure testing showed that the SUI-Li-ESWT group had significantly higher leak point pressures compared with untreated rats. Increased urethral and vaginal smooth and striated muscle content and increased thickness of the vaginal wall were noted in the SUI-Li-ESWT group. The SUI group had significantly decreased neuronal nitric oxide /tyrosine hydroxylase positive nerves ratio in the smooth muscle layers of the urethra, while the SUI-Li-ESWT group had neuronal nitric oxide/tyrosine hydroxylase+ nerves ratio similar to that of the control group. The continuality of urothelial cell lining was also improved in the SUI-Li-ESWT group. In addition, there were significantly increased EdU-positive cells in the SUI-Li-ESWT group., Conclusion: Li-ESWT appears to increase smooth muscle content in the urethra and the vagina, increase the thickness of urethral wall, improve striated muscle content and neuromuscular junctions, restore the integrity of the urothelium, and increase the number of EdU-retaining progenitor cells in the urethral wall., (Copyright © 2020 Elsevier Inc. All rights reserved.)

Aim: To investigate the possibility and mechanism of microenergy acoustic pulses (MAP) for activating tissue resident stem/progenitor cells within pelvic and urethral muscle and possible mechanism., Methods: The female Zucker Lean and Zucker Fatty rats were randomly divided into four groups: ZL control, ZLMAP, ZF control, and ZFMAP. MAP was applied at 0.033 mJ/mm 2 , 3 Hz for 500 pulses, and the urethra and pelvic floor muscles of each rat was then harvested for cell isolation and flow cytometry assay. Freshly isolated cells were analyzed by flow cytometry for Pax-7, Int-7α, H3P, and EdU expression. Meanwhile, pelvic floor muscle-derived stem cells (MDSCs) were harvested through magnetic-activated cell sorting, MAP was then applied to MDSCs to assess the mechanism of stem cell activation., Results: Obesity reduced EdU-label-retaining cells and satellite cells in both pelvic floor muscle and urethra, while MAP activated those cells and enhanced cell proliferation, which promoted regeneration of striated muscle cells of the pelvic floor and urethral sphincter. Activation of focal adhesion kinase (FAK)/AMP-activated protein kinase (AMPK) /Wnt/β-catenin signaling pathways by MAP is the potential mechanism., Conclusions: MAP treatment activated tissue resident stem cells within pelvic floor and urethral muscle in situ via activating FAK-AMPK and Wnt/β-catenin signaling pathway., (© 2019 Wiley Periodicals, Inc.)

Aim: Obesity is a strong independent risk factor for urinary incontinence. Effective therapeutic approaches for obesity-associated stress urinary incontinence (OA-SUI) are lacking as the mechanisms remain unclear. The aim of our study is to explore the impacts of microenergy acoustic pulse (MAP) therapy on urethral and pelvic floor muscle structure and function in female lean and fatty rats., Methods: A total 24 Zucker fatty (ZF) and 24 Zucker lean (ZL) female 24-week-old rats were grouped into four groups: ZL control, ZLMAP, ZF control, and ZFMAP. For MAP treatment, 500 pulses were delivered at an energy level of 0.033 mJ/mm 2 and a frequency of 3 Hz and were applied twice a week for 4 weeks. After a 1-week washout, all rats underwent conscious cystometry and leak-point pressure (LPP) measurements followed by ex vivo organ-bath assay and histological study., Results: ZF rats had lower LPP as compared to ZL rats, and MAP treatment significantly improved LPP in ZF rats (P < .05). Impaired muscle contractile activity (MCA) in organ-bath study was noted in ZF rats. MAP treatment significantly increased MCA in ZF rats (P < .05) and also increased the thickness of the striated muscle layer and the number of neuromuscular junctions (NMJs). In situ, MAP activated muscle satellite cells significantly (P < .05)., Conclusions: Obesity impairs the function of both the urethral sphincter and the pelvic floor and leads to atrophy and distortion of the striated muscle in obese female rats. These issues contribute to OA-SUI. MAP improves continence by stimulating muscle regeneration and nerve innervation as well as by activating satellite cells., (© 2019 Wiley Periodicals, Inc.)