Treatment of stress urinary incontinence with low-intensity extracorporeal shock wave therapy in a vaginal balloon dilation induced rat model

Age-Related Changes in Urethral Structure and Responds to Injury: Single-Cell Atlas of a Rat Model of Vaginal Birth Injury induced Stress Urinary Incontinence

Stress urinary incontinence (SUI) greatly affects the daily life of numerous women and is closely related to a history of vaginal delivery and aging. We used vaginal balloon dilation to simulate vaginal birth injury in young and middle-aged rats to produce a SUI animal model, and found that young rats restored urethral structure and function well, but not the middle-aged rats. To identify the characteristics of cellular and molecular changes in the urethral microenvironment during the repair process of SUI. We profiled 51,690 individual female rat urethra cells from 24 and 48 weeks old, with or without simulated vaginal birth injury. Cell interaction analysis showed that signal networks during repair process changed from resting to active, and aging altered the distribution but not the overall level of cell interaction in the repair process. Similarity analysis showed that muscle, fibroblasts, and immune cells underwent large transcriptional changes during aging and repair. In middle-aged rats, cell senescence occurs mainly in the superficial and middle urothelium due to cellular death and shedding, and the basal urothelium expressed many Senescence-Associated Secretory Phenotype (SASP) genes. In conclusion, we established the aging and vaginal balloon dilation (VBD) model of female urethral cell anatomy and the signal network landscape, which provides an insight into the normal or disordered urethra repair process and the scientific basis for developing novel SUI therapies.

Effects of Therapeutic Platelet-Rich Plasma on Overactive Bladder via Modulating Hyaluronan Synthesis in Ovariectomized Rat

Postmenopausal women who have ovary hormone deficiency (OHD) may experience urological dysfunctions, such as overactive bladder (OAB) symptoms. This study used a female Sprague Dawley rat model that underwent bilateral ovariectomy (OVX) to simulate post-menopause in humans. The rats were treated with platelet-rich plasma (PRP) or platelet-poor plasma (PPP) after 12 months of OVX to investigate the therapeutic effects of PRP on OHD-induced OAB. The OVX-treated rats exhibited a decrease in the expression of urothelial barrier-associated proteins, altered hyaluronic acid (hyaluronan; HA) production, and exacerbated bladder pathological damage and interstitial fibrosis through NFƘB/COX-2 signaling pathways, which may contribute to OAB. In contrast, PRP instillation for four weeks regulated the inflammatory fibrotic biosynthesis, promoted cell proliferation and matrix synthesis of stroma, enhanced mucosal regeneration, and improved urothelial mucosa to alleviate OHD-induced bladder hyperactivity. PRP could release growth factors to promote angiogenic potential for bladder repair through laminin/integrin-α6 and VEGF/VEGF receptor signaling pathways in the pathogenesis of OHD-induced OAB. Furthermore, PRP enhanced the expression of HA receptors and hyaluronan synthases (HAS), reduced hyaluronidases (HYALs), modulated the fibroblast-myofibroblast transition, and increased angiogenesis and matrix synthesis via the PI3K/AKT/m-TOR pathway, resulting in bladder remodeling and regeneration.

Use of low-intensity extracorporeal shock wave therapy in the management of interstitial cystitis/bladder pain syndrome patients: A thirty case study in a tertiary medical center

INTRODUCTION

Low-energy extracorporeal shock wave therapy (LiESWT) is a new potential treatment for intractable interstitial cystitis/bladder pain syndrome (IC/BPS), and this paper will evaluate its therapeutic effects on IC/BPS.

MATERIALS AND METHODS

This prospective clinical trial enrolled 30 women who have been diagnosed with IC/PBS to receive LiESWT treatment at an intensity of 0.25 mJ/mm² and a frequency of 3 pulses/second, for a total of 3000 pulses within 8 weeks. And we assessed questionnaires (including O'Leary-Sant Interstitial Cystitis Symptom Index (ICSI)), 3-day voiding diary, and urodynamic study at the following intervals: 4 weeks of LiESWT (W4), 8 weeks of LiESWT (W8), 1-month follow-up (F1), 3-month follow-up (F3) after LiESWT, and 1 year follow-up (F12).

RESULTS

The primary outcome of questionnaires showed significant improvement of symptoms compared to baseline (W0), especially on ICSI(12.87 ± 3.44 before treatment and 7.87 ± 5.27 at F12, p < 0.05). 3-day voiding diary also revealed significant decrease in daytime voiding frequency (15.57 ± 5.22 times before treatment and 10.70 ± 4.21 times at F1, p < 0.05) and significant increase on average voiding volume (95.85 ± 35.30 mL before treatment and 161.27 ± 74.21 mL at F1, p < 0.05). However, there were no significant differences in all parameters of the urodynamic study.

CONCLUSION

LiESWT can mitigate pain and lower urinary tract symptoms and improve the quality of life in IC/PBS patients, but does not increase the maximal cystometric capacity.

Muscle-derived Stem Cells Combined With Nerve Growth Factor Transplantation in the Treatment of Stress Urinary Incontinence

OBJECTIVE

To investigate the efficacy of muscle-derived stem cells (MDSCs) combined with nerve growth factor (NGF) in the treatment of stress urinary incontinence (SUI) METHODS: MDSCs were isolated and extracted from 90 SD rats, and the stem cell characteristics of the cells were identified using flow cytometry. NGF overexpression (oe-NGF) plasmid was coated with adenovirus and qRT-PCR was applied to verify adenovirus transfection efficiency. The rat models of SUI were constructed and randomly divided into 5 groups: control group, phosphate buffer (PBS) group, MDSCs + oe-NGF group, MDSCs + vector group, and MDSCs group. After 8 weeks of feeding, the leakage point pressure (LPP) rats, and Masson staining of rat urethral sections were detected. The expression of NGF and vascular endothelial growth factor (VEGF) was detected by western blot and IHC staining.

RESULTS

Compared with the control group, the LPP and the ratio of muscle fibers/collagen fibers were significantly increased in the MDSCs treated groups, with the highest increase in the MDSCs + oe-NGF group. Western blot and IHC results showed that the expression of NGF and VEGF in the urethral tissues in the MDSCs treated groups were significantly up-regulated comparing with the control group, with the highest increase in the MDSCs + oe-NGF group.

CONCLUSION

MDSCs alone can relieve SUI, while MDSCs combined with NGF is more effective, which may be related to the up-regulating of VEGF.

Microenergy acoustic pulse therapy restores urethral wall integrity and continence in a rat model of female stress incontinence

OBJECTIVE

To determine the outcomes and mechanisms of microenergy acoustic pulse (MAP) therapy in an irreversible rat model of female stress urinary incontinence.

MATERIALS AND METHODS

Twenty-four female Sprague-Dawley rats were randomly assigned into four groups: sham control (sham), vaginal balloon dilation and ovariectomy (VBDO), VBDO + β-aminopropionitrile (BAPN), and VBDO + β-aminopropionitrile treated with MAP (MAP). MAP therapy was administered twice per week for 4 weeks. After a 1-week washout period, all 24 rats were evaluated with functional and histological studies. The urethral vascular plexus was examined by immunofluorescence staining with antibodies against collagen IV and von Willebrand factor (vWF). The urethral smooth muscle stem/progenitor cells (uSMPCs) were isolated and functionally studied in vivo and in vitro.

RESULTS

Functional study with leak point pressure (LPP) measurement showed that the MAP group had significantly higher LPPs compared to VBDO and BAPN groups. MAP ameliorated the decline in urethral wall thickness and increased the amount of extracellular matrix within the urethral wall, especially in the urethral and vaginal elastic fibers. MAP also improved the disruption of the urethral vascular plexus in the treated animals. In addition, MAP enhanced the regeneration of urethral and vaginal smooth muscle, and uSMPCs could be induced by MAP to differentiate into smooth muscle and neuron-like cells in vitro.

CONCLUSION

MAP appears to restore urethral wall integrity by increasing muscle content in the urethra and the vagina and by improving the urethral vascular plexus and the extracellular matrix.

Molecular Processes in Stress Urinary Incontinence: A Systematic Review of Human and Animal Studies

Stress urinary incontinence (SUI) is a common and burdensome condition. Because of the large knowledge gap around the molecular processes involved in its pathophysiology, the aim of this review was to provide a systematic overview of genetic variants, gene and protein expression changes related to SUI in human and animal studies. On 5 January 2021, a systematic search was performed in Pubmed, Embase, Web of Science, and the Cochrane library. The screening process and quality assessment were performed in duplicate, using predefined inclusion criteria and different quality assessment tools for human and animal studies respectively. The extracted data were grouped in themes per outcome measure, according to their functions in cellular processes, and synthesized in a narrative review. Finally, 107 studies were included, of which 35 used animal models (rats and mice). Resulting from the most examined processes, the evidence suggests that SUI is associated with altered extracellular matrix metabolism, estrogen receptors, oxidative stress, apoptosis, inflammation, neurodegenerative processes, and muscle cell differentiation and contractility. Due to heterogeneity in the studies (e.g., in examined tissues), the precise contribution of the associated genes and proteins in relation to SUI pathophysiology remained unclear. Future research should focus on possible contributors to these alterations.

New Frontiers of Extracorporeal Shock Wave Medicine in Urology from Bench to Clinical Studies

A shock wave (SW), which carries energy and propagates through a medium, is a type of continuous transmitted sonic wave that can achieve rapid energy transformations. SWs have been applied for many fields of medical science in various treatment settings. In urology, high-energy extracorporeal SWs have been used to disintegrate urolithiasis for 30 years. However, at lower energy levels, SWs enhance the expression of vascular endothelial growth factor (VEGF), endothelial nitric oxide synthase (eNOS), proliferating cell nuclear antigen (PCNA), chemoattractant factors, and the recruitment of progenitor cells, and inhibit inflammatory molecules. Low energy extracorporeal shock wave (LESW) therapy has been used in urology for treating chronic prostatitis/chronic pelvic pain syndrome (CP/CPPS), interstitial cystitis/bladder pain syndrome (IC/BPS), overactive bladder, stress urinary incontinence, and erectile dysfunction through the mechanisms of anti-inflammation, neovascularization, and tissue regeneration. Additionally, LESW have been proven to temporarily increase tissue permeability and facilitate intravesical botulinum toxin delivery for treating overactive bladders in animal studies and in a human clinical trial. LESW assisted drug delivery was also suggested to have a synergistic effect in combination with cisplatin to improve the anti-cancer effect for treating urothelial cancer in an in vitro and in vivo study. LESW assisted drug delivery in uro-oncology is an interesting suggestion, but no comprehensive clinical trials have been conducted as of yet. Taken together, LESW is a promising method for the treatment of various diseases in urology. However, further investigation with a large scale of clinical studies is necessary to confirm the real role of LESW in clinical use. This article provides information on the basics of SW physics, mechanisms of action on biological systems, and new frontiers of SW medicine in urology.

Perinatal mesenchymal stromal cells of the human decidua restore continence in rats with stress urinary incontinence induced by simulated birth trauma and regulate senescence of fibroblasts from women with stress urinary incontinence

Stress urinary incontinence (SUI) is a condition that causes the involuntary loss of urine when making small efforts, which seriously affects daily life of people who suffer from it. Women are more affected by this form of incontinence than men, since parity is the main risk factor. Weakening of the pelvic floor tissues is the cause of SUI, although a complete understanding of the cellular and molecular mechanisms of the pathology is still lacking. Reconstructive surgery to strengthen tissue in SUI patients is often associated with complications and/or is ineffective. Mesenchymal stromal cells from the maternal side of the placenta, i.e. the decidua, are proposed here as a therapeutic alternative based on the regenerative potential of mesenchymal cells. The animal model of SUI due to vaginal distention simulating labor has been used, and decidual mesenchymal stromal cell (DMSC) transplantation was effective in preventing a drop in pressure at the leak point in treated animals. Histological analysis of the urethras from DMSC-treated animals after VD showed recovery of the muscle fiber integrity, low or no extracellular matrix (ECM) infiltration and larger elastic fibers near the external urethral sphincter, compared to control animals. Cells isolated from the suburethral connective tissue of SUI patients were characterized as myofibroblasts, based on the expression of several specific genes and proteins, and were shown to achieve premature replicative senescence. Co-culture of SUI myofibroblasts with DMSC via transwell revealed a paracrine interaction between the cells through signals that mediated DMSC migration, SUI myofibroblast proliferation, and modulation of the proinflammatory and ECM-degrading milieu that is characteristic of senescence. In conclusion, DMSC could be an alternative therapeutic option for SUI by counteracting the effects of senescence in damaged pelvic tissue.

Low Intensity Extracorporeal Shock Wave Therapy as a Novel Treatment for Stress Urinary Incontinence: A Randomized-Controlled Clinical Study

Background and Objectives: To evaluate the effects of low intensity extracorporeal shock wave therapy (LiESWT) on stress urinary incontinence (SUI). Materials and Methods: This investigation was a multicenter, single-blind, randomized-controlled trial study. Sixty female SUI patients were randomly assigned to receive LiESWT with 0.25 mJ/mm² intensity, 3000 pulses, and 3 pulses/s, once weekly for a 4-week (W4) and 8-week (W8) period, or an identical sham LiESWT treatment without energy transmission. The primary endpoint was the changes in urine leakage as measured by a pad test and validated standardized questionnaires, while the secondary endpoint was the changes in a 3-day urinary diary among the baseline (W0), the W4 and W8 of LiESWT, and 1-month (F1), 3-month (F3), and 6-month (F6) follow-up after LiESWT. Results: The results showed that 4 weeks of LiESWT could significantly decrease urine leakage based on the pad test and validated standardized questionnaire scores, as compared to the sham group. Moreover, 8 weeks of LiESWT could significantly reduce urine leakage but increase urine volume and attenuate urgency symptoms, which showed meaningful and persistent improvement at W8, F1, F3, and F6. Furthermore, validated standardized questionnaire scores were significantly improved at W8, F1, F3, and F6 as compared to the baseline (W0). Conclusions: Eight weeks of LiESWT attenuated SUI symptoms upon physical activity, reduced urine leakage, and ameliorated overactive bladder symptoms, which implied that LiESWT significantly improved the quality of life. Our findings suggested that LiESWT could serve as a potentially novel and non-invasive treatment for SUI.

Low-Intensity Extracorporeal Shock Wave Therapy Promotes Bladder Regeneration and Improves Overactive Bladder Induced by Ovarian Hormone Deficiency from Rat Animal Model to Human Clinical Trial

Postmenopausal women with ovary hormone deficiency (OHD) are subject to overactive bladder (OAB) symptoms. The present study attempted to elucidate whether low-intensity extracorporeal shock wave therapy (LiESWT) alters bladder angiogenesis, decreases inflammatory response, and ameliorates bladder hyperactivity to influence bladder function in OHD-induced OAB in human clinical trial and rat model. The ovariectomized (OVX) for 12 months Sprague–Dawley rat model mimicking the physiological condition of menopause was utilized to induce OAB and assess the potential therapeutic mechanism of LiESWT (0.12 mJ/mm², 300 pulses, and 3 pulses/second). The randomized, single-blinded clinical trial was enrolled 58 participants to investigate the therapeutic efficacy of LiESWT (0.25 mJ/mm², 3000 pulses, 3 pulses/second) on postmenopausal women with OAB. The results revealed that 8 weeks’ LiESWT inhibited interstitial fibrosis, promoted cell proliferation, enhanced angiogenesis protein expression, and elevated the protein phosphorylation of ErK1/2, P38, and Akt, leading to decreased urinary frequency, nocturia, urgency, urgency incontinence, and post-voided residual urine volume, but increased voided urine volume and the maximal flow rate of postmenopausal participants. In conclusion, LiESWT attenuated inflammatory responses, increased angiogenesis, and promoted proliferation and differentiation, thereby improved OAB symptoms, thereafter promoting social activity and the quality of life of postmenopausal participants.

The Effect of Low-intensity Shockwave Therapy on Non-neurogenic Lower Urinary Tract Symptoms: A Systematic Review and Meta-analysis of Preclinical and Clinical Studies

CONTEXT

Low-intensity shockwave therapy (LiST) has emerged as an effective treatment for pain in patients with chronic prostatitis/chronic pelvic pain syndrome (CP/CPPS), and it has been postulated that LiST may also be effective in patients with lower urinary tract symptoms (LUTS).

OBJECTIVE

To perform a systematic review and meta-analysis of experimental and clinical studies exploring the effect of LiST on LUTS in an attempt to provide clinical implications for future research.

EVIDENCE ACQUISITION

We systematically searched PubMed, Cochrane Library, and Scopus databases from inception to March 2021 for relevant studies. We provided a qualitative synthesis regarding the role of LiST in LUTS and performed a single-arm, random-effect meta-analysis to assess the absolute effect of LiST on LUTS only in patients with CP/CPPS (PROSPERO: CRD42021238281).

EVIDENCE SYNTHESIS

We included 23 studies (11 experimental studies, seven nonrandomized controlled trials [non-RCTs], and five RCTs) in the systematic review and seven in the meta-analysis. All experimental studies were performed on rats with LUTS, and the clinical studies recruited a total of 539 participants. In patients with CP/CPPS, the absolute effect of LiST on maximum flow rate and postvoid residual was clinically insignificant. However, the available studies suggest that LiST is effective for the management of pain in patients with either CP/CPPS or interstitial cystitis/bladder pain syndrome. Additionally, LiST after intravesical instillation of botulinum neurotoxin type A may enhance its absorption and substitute botulinum neurotoxin type A injections in patients with overactive bladder. Furthermore, the available evidence is inconclusive about the role of LiST in patients with benign prostatic obstruction, stress urinary incontinence, or underactive bladder/detrusor hypoactivity.

CONCLUSIONS

LiST may be effective for some disorders causing LUTS. Still, further studies on the matter are necessary, since the available evidence is scarce.

PATIENT SUMMARY

Low-intensity shockwave therapy represents a safe, easily applied, indolent, and repeatable on an outpatient basis treatment modality that may improve lower urinary tract symptoms.

Epidemiological survey of adult female stress urinary incontinence

Background

The prevalence of stress urinary incontinence (SUI) in adult female in Taiyuan and what are the related risk factors are not clear. The aim of this study was to provide a basis for exploring the prevention and treatment of SUI in adult female in Taiyuan.

Methods

A voluntary online questionnaire was used to investigate adult female in the community and surrounding townships of Taiyuan. Most of the questionnaires refer to the International Consultation on Incontinence Questionnaire-Female Lower Urinary Tract Symptoms, and adapt to the specific circumstances of the region. Data were analyzed using SPSS software (version 22.0).

Results

A total of 4004 eligible questionnaires were obtained. The prevalence of SUI in adult female in Taiyuan was 33.5%. Univariate analysis and multivariate logistic regression analysis showed that place of residence, smoking, body mass index, diet, number of deliveries, mode of delivery, dystocia, menopause, oral contraceptives, urinary tract infection, making the bladder empty faster by pushing down and holding urine were risk factors for adult female stress urinary incontinence in Taiyuan.

Conclusion

The prevalence of SUI in adult female in Taiyuan was high, and based on risk factors identified in this survey, population-level intervention strategies should be developed for the prevention and treatment of adult female SUI in Taiyuan.

Supplementary Information

The online version contains supplementary material available at 10.1186/s12905-021-01319-z.

Progress in studies on pathological changes and future treatment strategies of obesity-associated female stress urinary incontinence: a narrative review

With the increasing prevalence of obesity worldwide, obesity-related female stress urinary incontinence (FSUI) has become a key health problem. Recent studies indicated that FSUI is primarily caused by obesity-related pathological changes, such as fat droplet deposition, and results in pelvic floor nerve, vascular, and urethral striated muscle injury. Meanwhile, treatments for obesity-associated FSUI (OA-FSUI) have garnered much attention. Although existing OA-FSUI management strategies, including weight loss, pelvic floor muscle exercise, and urethral sling operation, could play a role in symptomatic relief; they cannot reverse the pathological changes in OA-FSUI. The continued exploration of safe and reliable treatments has led to regenerative therapy becoming a particularly promising area of researches. Specifically, micro-energy, such as low-intensity pulsed ultrasound (LIPUS), low-intensity extracorporeal shock wave therapy (Li-ESWT), and pulsed electromagnetic field (PEMF), have been shown to restore the underlying pathological changes of OA-FSUI, which might be related by regulation endogenous stem cells (ESCs) to restore urine control function ultimately in animal experiments. Therefore, ESCs may be a target for repairing pathological changes of OA-FSUI. The aim of this review was to summarize the OA-FSUI-related pathogenesis, current treatments, and to discuss potential therapeutic options. In particular, this review is focused on the effects and related mechanisms of micro-energy therapy for OA-FSUI to provide a reference for future basically and clinical researches.

Regenerating Urethral Striated Muscle by CRISPRi/dCas9-KRAB-Mediated Myostatin Silencing for Obesity-Associated Stress Urinary Incontinence

Overweight females are prone to obesity-associated stress urinary incontinence (OA-SUI), and there are no definitive medical therapies for this common urologic condition. This study was designed to test the hypothesis that regenerative therapy to restore urethral striated muscle (stM) and pelvic floor muscles might represent a valuable therapeutic approach. For the in vitro experiment, single-guide RNAs targeting myostatin (MSTN) were used for CRISPRi/dCas9-Kruppel associated box (KRAB)-mediated gene silencing. For the in vivo experiment, a total of 14 female lean ZUC-Leprfa 186 and 14 fatty ZUC-Leprfa 185 rats were used as control and CRISPRi-MSTN treated groups, respectively. The results indicated that lentivirus-mediated expression of MSTN CRISPRi/dCas9-KRAB caused sustained downregulation of MSTN in rat L6 myoblast cells and significantly enhanced myogenesis in vitro. In vivo, the urethral sphincter injection of lentiviral-MSTN sgRNA and lentiviral-dCas9-KRAB significantly increased the leak point pressure, the thickness of the stM layer, the ratio of stM to smooth muscle, and the number of neuromuscular junctions. Downregulation of MSTN with CRISPRi/dCas9-KRAB-mediated gene silencing significantly enhanced myogenesis in vitro and in vivo. It also improved urethral continence in the OA-SUI rat model.

Delayed Treatment With Low-intensity Extracorporeal Shock Wave Therapy in an Irreversible Rat Model of Stress Urinary Incontinence

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.

Therapeutic effects of Low intensity extracorporeal low energy shock wave therapy (LiESWT) on stress urinary incontinence

This study aimed to evaluate the therapeutic effects of Low intensity extracorporeal low energy shock wave therapy (LiESWT) on stress urinary incontinence (SUI). The investigation was a single-arm, open-label, multicentre study conducted in Taiwan. 50 female patients with SUI received LiESWT-treated with 0.25 mJ/mm² intensity, 3000 pulses, and 3 pulses/second, once weekly for 4-weeks (W4) and 8-weeks (W8). The pad test, uroflowmetry, life quality questionnaires, and 3-day urinary diary measurement were performed before and after LiESWT intervention. The results revealed that 8-week of LiESWT treatment meaningfully improved urine leakage (pad test), maximum flow rate, post-voided residual urine, average urine volume, functional bladder capacity, urinary frequency, urgency symptom, and nocturia, which also persisted to show significant improvements at 1-month follow up (F1). Moreover, bothersome questionnaires scores were significantly improved at W4, W8, and F1 as compared to the baseline (W0). These results indicated that 8 weeks of LiESWT attenuated SUI symptoms on physical activity, reduced bladder leaks and overactive bladder (OAB), implying that LiESWT brought significant improvement in the quality of life. (ClinicalTrials.gov number, NCT04059133).

Role and mechanism of micro-energy treatment in regenerative medicine

With the continuous integration and intersection of life sciences, engineering and physics, the application for micro-energy in the basic and clinical research of regenerative medicine (RM) has made great progress. As a key target in the field of RM, stem cells have been widely used in the studies of regeneration. Recent studies have shown that micro-energy can regulate the biological behavior of stem cells to repair and regenerate injured organs and tissues by mechanical stimulation with appropriate intensity. Integrins-mediated related signaling pathways may play important roles in transducing mechanical force about micro-energy. However, the complete mechanism of mechanical force transduction needs further research. The purpose of this article is to review the biological effect and mechanism of micro-energy treatment on stem cells, to provide reference for further research.

Microenergy acoustic pulses induced myogenesis of urethral striated muscle stem/progenitor cells

Background

Stress urinary incontinence (SUI) is a common disorder with high prevalence in women across their life span, but there are no non-surgical curative options for the condition. Stem cell-based therapy, especially endogenous stem cell therapy may be a potential treatment method for SUI. The aims of this study are to identify, isolate, and assay the function of urethral striated muscle derived stem/progenitor cells (uMDSCs) and to assess uMDSC response to microenergy acoustic pulses (MAP).

Methods

Urethral striated muscle was identified utilizing 3D imaging of solvent organs (3DISCO) and immunofluorescence (IF). uMDSCs were isolated and purified from Zucker Lean (ZL) (ZUC-LEAN) (ZUC-Leprfa 186) rats, with magnetic-activated cell sorting (MACS) and pre-plating methods. The stemness and differentiation potential of the uMDSCs were measured by cell proliferation, EdU, flow cytometry, IF, and Western blot.

Results

Comparison of the cell proliferation assays between MACS and pre-plating reveals the advantage of MACS over pre-plating. In addition, the study reveals that uMDSCs form myotubes when treated with MAP.

Conclusions

The uMDSCs within female rat urethral striated muscle could be a therapeutic target of MAP in managing SUI.

The effects of microenergy acoustic pulses on animal model of obesity-associated stress urinary incontinence. Part 2: In situ activation of pelvic floor and urethral striated muscle progenitor cells

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/mm² , 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.

Applicability of regenerative medicine and tissue engineering for the treatment of stress urinary incontinence in female patients

Stress urinary incontinence (SUI) is an age health-related issue that generates interest due to its considerable public health burden and the controversies surrounding treatment. It is highly prevalent affecting 30-40% of all women during their lifetime. Midurethral slings are the standard of gold standard treatment for female patients with SUI. They have excellent short-term cure rates; however, their efficacy tends to decrease over time and patients often report urinary incontinence recurrence. This paper addresses the applicability of regenerative medicine and tissue engineering for the treatment of SUI in female patients. Cell-based treatment with periurethral injection of autologous adipose or muscle-derived stem cells have been used for SUI; however, the cure rates and SUI recurrence at 1 year were 40% and 70%, respectively. Novel minimally invasive approaches, such as low-intensity extracorporeal shock wave therapies have shown promising results in SUI animal models. In addition, local injection of growth factors, chemokines, and specific antibodies have shown histological evidence of neoangiogenesis, nerve, and sphincter regeneration in rodents and nonhuman primates with SUI. The use of bioactive factors and proteins secreted by cells, which is called secretomes, have been recognized as key regulators of various mechanisms, such as immunomodulation, angiogenesis, inflammation, apoptosis, and tissue repair. Emerging therapies aiming to replace or restore tissues and organ functionality may improve the long-term efficacy and in the near future may represent the standard of care for the treatment of SUI.

Low Intensity Pulsed Ultrasound Influences the Myogenic Differentiation of Muscle Satellite Cells in a Stress Urinary Incontinence Rat Model

OBJECTIVE

To investigate the therapeutic effect of low intensity pulsed ultrasound (LIPUS) in a stress urinary incontinence (SUI) rat model and its influence on myogenic satellite cells.

METHODS

Fifty Sprague-Dawley rats underwent vaginal distension and bilateral ovariectomy mimicking partum injury and menopause to construct SUI models, which were further randomized into 100 mW/cm² LIPUS, 200 mW/cm² LIPUS, 300 mW/cm² LIPUS, and none-treatment control subgroups with 10 rats per subgroup. Ten rats served as mock operation control. Leak point pressure and bladder capacity were recorded 1 week after LIPUS treatment. Immunofluorescence staining and Western blot were performed to examine histological changes, myodifferentiation, and signaling pathway.

RESULTS

Here,we found the leak point pressure and bladder capacity were restored in 200 mW/cm² LIPUS and 300 mW/cm² LIPUS groups, but not in 100 mW/cm² LIPUS group. More robust striated muscle regeneration was observed in 200 mW/cm² LIPUS group comparing with the SUI none-treatment group. Moreover, we found LIPUS activated the myodifferentiation of muscle satellite cells, which is correlated to p38 phosphorylation level.

CONCLUSION

LIPUS restored the leak point pressure and bladder capacity, and activated satellite cell myodifferentiation in SUI rat model.