Will we ever use stem cells for the treatment of SUI? ICI-RS 2011

microRNA-181a-5p promotes fibroblast differentiation of mesenchymal stem cells in rats with pelvic floor dysfunction

The use of stem cells capable of multilineage differentiation in treating Pelvic Floor Dysfunction (PFD) holds great promise since they are susceptible to entering connective tissue of various cell types and repairing damaged tissues. This research investigated the effect of microRNA-181a-5p (miR-181a-5p) on Bone Marrow Mesenchymal Stem Cells (BMSCs) in rats with PFD. BMSCs were transfected and analyzed for their fibroblast differentiation ability. miR-181a-5p, MFN1, and fibroblast-related genes were quantitatively analyzed. Whether MFN1 is a target gene of miR-181a-5p was predicted and confirmed. The efficacy of BMSCs in vivo rats with PFD was evaluated by measuring Leak Point Pressure (LPP), Conscious Cystometry (CMG), hematoxylin and eosin staining, and Masson staining. The present results discovered that miR-181a-5p was up-regulated and MFN1 was down-regulated during the differentiation of BMSCs into fibroblasts. Fibroblast differentiation of BMSCs was promoted after miR-181a-5p was induced or MFN1 was suppressed, but it was suppressed after miR-181a-5p was silenced. miR-181a-5p improved LPP and conscious CMG outcomes in PDF rats by targeting MFN1 expression, thereby accelerating fibroblast differentiation of BMSCs. In brief, miR-181a-5p induces fibroblast differentiation of BMSCs in PDF rats by MFN1, potentially targeting PDF therapeutics.

Comparing Periurethral Injection of Autologous Muscle-Derived Stem Cell and Fibroblasts with Mid-Urethral Sling Surgery in the Treatment of Female Stress Urinary Incontinence: A Randomized Clinical Trial

Objective

In this study, we analyzed the therapeutic effect of periurethral injection of autologous muscle-derived stem cell versus mid-urethral sling surgery at a 1-year follow-up.

Method

This randomized controlled clinical trial was conducted on 30 women with stress urinary incontinence (SUI) who had not responded to conservative treatments, after registering the participants and obtaining informed consent. Patients were divided into two groups of 15 each treated with periurethral injection of muscle-derived stem cells (MDSCs) and mid-urethral sling surgery, respectively. Follow-ups were done at 1, 3, 6, and 12 months after the treatment using the International Consultation on Incontinence Questionnaire-Urinary Incontinence Short Form (ICIQ-UISF) and Incontinence Quality of Life Questionnaire (I-QOL) questionnaires, clinical examination, cough test, and 1-hour pad test. The results were analyzed within the groups and then compared between the two groups. Moreover, both groups were compared in terms of postoperative complications.

Results

At the 1-year follow-up, in the stem cell group, 10 patients (66.6%) experienced improvements after the periurethral injection of stem cells; half of these patients (33.3%) reported a full recovery. In the mid-urethral sling group, 13 patients (93.3%) experienced improvement, and 12 patients (80%) reported a full recovery. The analysis of ICIQ-UISF and I-QOL questionnaires indicated that the responses in both groups were significant, but the response in the stem cell group was significantly lower compared with the standard surgery group. No considerable complications were observed in the two groups.

Conclusion

Although the periurethral injection of MDSCs considerably improves the symptoms with minimum complications in women with SUI, its therapeutic response is significantly lower compared with mid-urethral sling surgery.

Stress urinary incontinence in females. Diagnosis and treatment modalities – past, present and the future

Introduction:

Stress urinary incontinence (SUI) can be defined as involuntary and unintentional loss of urine through the urethra when vesical pressure exceeds the urethral sphincter pressure during instances of coughing, sneezing or physical exercise. Stress urinary incontinence is the most common form of incontinence in females with an estimated prevalence of 4.5–53% in adult women with urinary incontinence. Yet despite its distressing nature and a negative impact on quality of life, very few women present with their symptoms to a urologist.

Materials and methods:

A literature search of the MEDLINE, Cochrane Library, Embase, NLH, ClinicalTrials.gov and Google Scholar databases was done up to November 2020, using terms related to SUI, medical therapy, surgical therapy and treatment options. The search terms included female stress urinary incontinence, mid-urethral sling, tension-free vaginal tape and trans obturator tape. The search included original articles, reviews and meta-analyses.

Conclusion:

Current guidelines for the management of stress urinary incontinence propose a step-ladder pattern, based on treatment invasiveness starting from conservative therapies, then drugs followed by minimally invasive procedures and culminating in invasive surgeries. The surgical approach is to be considered only after conservative therapies fail. The recent advances in the treatment of stress urinary incontinence have brought to light newer modalities and newer technologies that can be utilized which include laser therapy, stem cell therapy, intravesical balloon and others that show a lot of promise. This paper provides an in-depth analysis and reviews the literature on the current modalities and the future prospects of female stress urinary incontinence.

Level of evidence:

Not applicable for this review article.

BMMSC-sEV-derived miR-328a-3p promotes ECM remodeling of damaged urethral sphincters via the Sirt7/TGFβ signaling pathway

Background

Stress urinary incontinence (SUI) is a common and bothersome condition. Invasive surgery will always be considered after conservative treatment fails, but the rates of postoperative complications and long-term recurrence are high. Thus, a new treatment strategy is still needed. In recent years, bone marrow mesenchymal stem cells (BMMSC) have shown great promise for SUI treatment. The therapeutic effects of BMMSC on SUI are achieved mainly by paracrine pathway signaling molecules, such as small extracellular vesicles (sEV). sEV are recognized as essential mediators of cell-to-cell communication. However, the therapeutic effects and detailed mechanisms of BMMSC-derived sEV in SUI remain mostly unexplored.

Methods

The effects of BMMSC-sEV on extracellular matrix (ECM) metabolism were assessed in vitro and in vivo. In a SUI rat model, TGF-β1 signaling was examined with or without BMMSC-sEV stimulation. sEV miRNAs were deeply sequenced, and the most likely miRNAs were evaluated as mediators of the TGF-β1 signaling pathway.

Results

BMMSC-sEV enhanced the synthesis of ECM components, including elastin, collagen I, and collagen III, and improved urethral function. Furthermore, BMMSC-sEV activated TGF-β1 signaling in primary fibroblast cells and in rat urethras. Several differentially expressed miRNAs were identified in the BMMSC-sEV. Bioinformatics analysis and in vitro studies showed that BMMSC-sEV miR-328a-3p can be transferred from BMMSC to fibroblasts and can regulate the Sirt7/TGF-β1 signaling pathway.

Conclusion

BMMSC-sEV promote ECM remodeling of damaged urethral sphincters by transferring miR-328a-3p to regulate the Sirt7/TGF-β1 signaling pathway.

Recovery of motricity and micturition after transplantation of mesenchymal stem cells in rats subjected to spinal cord injury

The objective was to evaluate the effect of human adipose-derived stem cell (hADSC) infusion on impaired hindlimb function and urinary continence after spinal cord contusion in rats. hADSCs were transplanted into the injured spinal cords of rats 7 and 14 days after injury in two groups (B and C). Group C also received methylprednisolone sodium succinate (MPSS) after 3 h of injury. The control group (group A) did not receive corticoids or stem cells. Voiding and motor performance evaluations were performed daily for 90 days post-transplantation. Cells were labeled with PKH26 or PKH67 for in vitro monitoring. For in vivo screening, the cells were evaluated for bioluminescence. The levels of some cytokines were quantified in different times. Euthanasia was performed 90 days post-transplant. β-tubulin III expression was evaluated in the spinal cord of the animals from all groups. As a result, we observed a recovery of 66.6 % and 61.9 % in urinary continence of animals from groups B and C, respectively. Partial recovery of motor was observed in 23.8 % and 19 % of the animals from groups B and C, respectively. Cells remained viable at the site up to 90 days after transplantation. No significant difference was observed in levels of cytokines and thickness of urinary bladders between groups. A smaller percentage of tissue injury and higher concentrations of neuropils were observed in the spinal cords of the animals from groups B and C than control group. Thus, hADSCs transplantation with or without MPSS, contributed to the improvement in voiding and motor performance of Wistar rats submitted to compressive spinal cord injury.

Stem cell applications in regenerative medicine for stress urinary incontinence: A review of effectiveness based on clinical trials

Objective

To evaluate the current state, therapeutic benefit and safety of urethral injection of autologous stem cells for the treatment stress urinary incontinence (SUI).

Materials and methods

A selective database search of PubMed, the Excerpta Medica dataBASE (EMBASE), Cochrane Library and Google Scholar was conducted to validate the effectiveness of stem cell-based therapy. The search included clinical trials published up until 4 January 2020, written in English, and included cohorts of women and men who had received stem cell-based therapy for SUI. The search used the following keywords in various combinations: ‘stem cell therapy’, ‘cell-based therapy for SUI’, ‘regenerative medicine for SUI’, and ‘tissue engineering’. The success rates were assessed according to cough test, urodynamics, pad tests, and International Consultation on Incontinence Questionnaire-Urinary Incontinence. The primary endpoint was continence rate to measure objectively the effect of the treatment.

Results

We identified four clinical trials using local injections of adipose-derived stem cells (ADSCs), 11 trails with muscle-derived stem cells (MDSCs), and two trails with human umbilical cord blood stem cells (HUCBs) and total nucleated cells (TNCs). The median improvement rate of intrinsic sphincter deficiency after ADSCs, MDSCs, TNCs, HUCBs injections were 88%, 77%, 89%, 36% (improvement rate: 1–2 pads) at a mean (range) follow-up of 6 (1–72) months. The cell sources, methods of cell processing, cell number, and implantation techniques differed considerably between studies. Most of the periurethral injections were at the 3, 5, 7, and 9 o’clock positions and for submucosa were at the 4, 6, and 8 o’clock positions. No significant postoperative complications were reported.

Conclusion

Despite many challenges in stem cell-based therapy for treating SUI, it appears to provide, in both male and female patients, acceptable functional results with minimal side-effects and complications. In the future, more clinical trials should be funded in order to optimise stem cell-based therapy and evaluate long-term outcomes.

Abbreviations

ADSC: adipose-derived stem cell; BMSCs: bone marrow-derived mesenchymal stem cell; CLPP: cough leak-point pressure; FPL: functional profile length; HUCB: human umbilical cord blood stem cell; ICIQ-(QOL)(SF)(UI): International Consultation on Incontinence Questionnaire (Quality of life) (-Urinary incontinence Short Form) (-Urinary Incontinence); IIQ-7: Incontinence Impact Questionnaire-short form; I-QOL: Incontinence quality of life questionnaire; ISD: intrinsic urinary sphincter deficiency; MDSC: muscle-derived stem cell; MUCP: maximum urethral closure pressure; NR: not reported; Pdet-max: maximum detrusor pressure; PVR: post-void residual urine volume; Q_max: maximum urinary flow; QOL: quality of life; RP: radical prostatectomy; TNC: total nucleated cell; (S)UI: (stress) urinary incontinence; UDSCs: urine-derived stem cells; UTUS: upper tract ultrasonography; VLPP: Valsalva leak-point pressure

Advances in stem cell therapy for male stress urinary incontinence

INTRODUCTION

Among the several options that have been proposed in recent years for the management of male stress urinary incontinence (SUI), stem cell therapy represents a new frontier in treatment. The aim of this paper is to update the current status of stem cell therapy in animal and human studies for the management of iatrogenic male SUI.

AREAS COVERED

A literature review was conducted based on MEDLINE/PubMed searches for English articles using a combination of the following keywords: stem cell therapy, urinary incontinence, prostatectomy, regenerative medicine, mesenchymal stem cells.

EXPERT OPINION

The few studies reported in the literature have demonstrated short-term safety and promising results of stem cell therapy in treating male SUI. However, many aspects need to be clarified before stem cell therapy can be introduced into daily urologic practice. In fact, important issues such as the limitations of these studies in terms of small sample sizes and short follow-ups, the incomplete knowledge of the mechanism of action of stem cells, the technical details regarding the delivery method and the best sources of stem cells, the safety risks regarding genomic or epigenetic changes and potential immune reactions in the longer term need to be identified in more stringent clinical trials.

Stem Cells for Urinary Incontinence: Functional Differentiation or Cytokine Effects?

Minimally invasive stem cell therapy for stress urinary incontinence may provide an effective nonsurgical treatment for this common condition. Clinical trials of periurethral stem cell injection have been under way, and basic science research has demonstrated the efficacy of both local and systemic stem cell therapies. Results differ as to whether stem cells have a therapeutic effect by differentiating into permanent, functional tissues or exert benefits through a transient presence and the secretion of regenerative factors. This review explores the fate of therapeutic stem cells for stress urinary incontinence and how this may relate to their mechanism of action.

MicroRNA-29 facilitates transplantation of bone marrow-derived mesenchymal stem cells to alleviate pelvic floor dysfunction by repressing elastin

Background

Pelvic floor dysfunction (PFD) is a condition affecting many women worldwide, with symptoms including stress urinary incontinence (SUI) and pelvic organ prolapse (POP). We have previously demonstrated stable elastin-expressing bone marrow-derived mesenchymal stem cells (BMSCs) attenuated PFD in rats, and aim to further study the effect of microRNA-29a-3p regulation on elastin expression and efficacy of BMSC transplantation therapy.

Methods

We inhibited endogenous microRNA-29a-3p in BMSCs and investigated its effect on elastin expression by RT-PCR and Western blot. MicroRNA-29-inhibited BMSCs were then transplanted into PFD rats, accompanied by sustained release of bFGF using formulated bFGF in poly (lactic-co-glycolic acid) (PLGA) nanoparticles (NP), followed by evaluation of urodynamic tests.

Results

MicroRNA-29a-3p inhibition resulted in upregulated expression and secretion of elastin in in vitro culture of BMSCs. After co-injection with PLGA-loaded bFGF NP into the PFD rats in vivo, microRNA-29a-3p-inhibited BMSCs significantly improved the urodynamic test results.

Conclusions

Our multidisciplinary study, combining microRNA biology, genetically engineered BMSCs, and nanoparticle technology, provides an excellent stem cell-based therapy for repairing connective tissues and treating PFD.

Transplantation of bone marrow-derived mesenchymal stem cells expressing elastin alleviates pelvic floor dysfunction

Background

Pelvic floor dysfunction (PFD) is a group of clinical conditions including stress urinary incontinence (SUI) and pelvic organ prolapse (POP). The abnormality of collagen and elastin metabolism in pelvic connective tissues is implicated in SUI and POP.

Methods

To reconstitute the connective tissues with normal distribution of collagen and elastin, we transduced elastin to bone marrow-derived mesenchymal stem cells (BMSC). Elastin-expressing BMSCs were then differentiated to fibroblasts using bFGF, which produced collagen and elastin. To achieve the sustained release of bFGF, we formulated bFGF in poly (lactic-co-glycolic acid) (PLGA) nanoparticles (NP).

Results

In an in vitro cell culture system of 7 days, when no additional bFGF was administrated, the initial PLGA-loaded bFGF NP induced prolonged production of collagen and elastin from elastin-expressing BMSCs. In vivo, co-injection of PLGA-loaded bFGF NP and elastin-expressing BMSCs into the PFD rats significantly improved the outcome of urodynamic tests. Together, these results provided an efficient model of connective tissue engineering using BMSC and injectable PLGA-loaded growth factors.

Conclusions

Our results provided the first instance of a multidisciplinary approach, combining both stem cell and nanoparticle technologies, for the treatment of PFD.

Clinical Guideline for Female Lower Urinary Tract Symptoms

The "Japanese Clinical Guideline for Female Lower Urinary Tract Symptoms," published in Japan in November 2013, contains two algorithms (a primary and a specialized treatment algorithm) that are novel worldwide as they cover female lower urinary tract symptoms other than urinary incontinence. For primary treatment, necessary types of evaluation include querying the patient regarding symptoms and medical history, examining physical findings, and performing urinalysis. The types of evaluations that should be performed for select cases include evaluation with symptom/quality of life (QOL) questionnaires, urination records, residual urine measurement, urine cytology, urine culture, serum creatinine measurement, and ultrasonography. If the main symptoms are voiding/post-voiding, specialized treatment should be considered because multiple conditions may be involved. When storage difficulties are the main symptoms, the patient should be assessed using the primary algorithm. When conditions such as overactive bladder or stress incontinence are diagnosed and treatment is administered, but sufficient improvement is not achieved, the specialized algorithm should be considered. In case of specialized treatment, physiological re-evaluation, urinary tract/pelvic imaging evaluation, and urodynamic testing are conducted for conditions such as refractory overactive bladder and stress incontinence. There are two causes of voiding/post-voiding symptoms: lower urinary tract obstruction and detrusor underactivity. Lower urinary tract obstruction caused by pelvic organ prolapse may be improved by surgery.

Viability and MR detectability of iron labeled mesenchymal stem cells used for endoscopic injection into the porcine urethral sphincter

Direct stem cell therapies for functionally impaired tissue require a sufficient number of cells in the target region and a method for verifying the fate of the cells in the subsequent time course. In vivo MRI of iron labeled mesenchymal stem cells has been suggested to comply with these requirements. The study was conducted to evaluate proliferation, migration, differentiation and adhesion effects as well as the obtained iron load of an iron labeling strategy for mesenchymal stem cells. After injection into the porcine urethral sphincter, the labeled cells were monitored for up to six months using MRI. Mesenchymal stem cells were labeled with ferucarbotran (60/100/200 µg/mL) and ferumoxide (200 µg/mL) for the analysis of migration and viability. Phantom MR measurements were made to evaluate effects of iron labeling. For short and long term studies, the iron labeled cells were injected into the porcine urethral sphincter and monitored by MRI. High resolution anatomical images of the porcine urethral sphincter were applied for detection of the iron particles with a turbo-spin-echo sequence and a gradient-echo sequence with multiple TE values. The MR images were then compared with histological staining. The analysis of cell function after iron labeling showed no effects on proliferation or differentiation of the cells. Although the adherence increases with higher iron dose, the ability to migrate decreases as a presumed effect of iron labeling. The iron labeled mesenchymal stem cells were detectable in vivo in MRI and histological staining even six months after injection. Labeling with iron particles and subsequent evaluation with highly resolved three dimensional data acquisition allows sensitive tracking of cells injected into the porcine urethral sphincter for several months without substantial biological effects on mesenchymal stem cells.

The potential role of stem cells in the treatment of urinary incontinence

Voiding dysfunction encompasses a wide range of urologic disorders including stress urinary incontinence and overactive bladder that have a detrimental impact on the quality of life of millions of men and women worldwide. In recent years, we have greatly expanded our understanding of the pathophysiology of these clinical conditions. However, current gold standard therapies often provide symptomatic relief without targeting the underlying etiology of disease development. Recently, the use of stem cells to halt disease progression and reverse underlying pathology has emerged as a promising method to restore normal voiding function. Stem cells are classically thought to aid in tissue repair via their ability for multilineage differentiation and self-renewal. They may also exert a therapeutic effect via the secretion of bioactive factors that direct other stem and progenitor cells to the area of injury, and that also possess antiapoptotic, antiscarring, neovascularization, and immunomodulatory properties. Local injections of mesenchymal, muscle-derived, and adipose-derived stem cells have all yielded successful outcomes in animal models of mechanical, nerve, or external urethral sphincter injury in stress urinary incontinence. Similarly, direct injection of mesenchymal and adipose-derived stem cells into the bladder in animal models of bladder overactivity have demonstrated efficacy. Early clinical trials using stem cells for the treatment of stress urinary incontinence in both male and female patients have also achieved promising functional results with minimal adverse effects. Although many challenges remain to be addressed prior to the clinical implementation of this technology, novel stem-cell-based therapies are an exciting potential therapy for voiding dysfunction.

Management of urinary incontinence after radical prostatectomy

In the year following a radical prostatectomy, most men recover from any initial urinary incontinence. Nonetheless, incontinence greatly affects a man's quality of life during that time, as it does for those who have persistent incontinence thereafter. Urological assessment should be thorough in order to ensure that no treatable etiology exists aside from stress incontinence. Conservative measures can then be applied from the earliest stages, and offer benefit for those with mild to moderate symptoms. Failing this, a wide variety of surgical options can be considered. For effective outcomes, a clinician must ensure that surgical decision-making is based on current evidence and patient preference, and that it considers possible morbidities.

Injectable treatments for female stress urinary incontinence

The use of injectable agents for the treatment of stress urinary incontinence (SUI) is an option for female patients who are unwilling to undergo surgery, or have concurrent conditions or diseases that render surgical treatment unsuitable. To be effective for SUI, an injectable agent must be nonimmunogenic, hypoallergenic, biocompatible, permanent, nonerosive, nonmigratory and painless. It must also heal with minimal fibrosis, possess a long-term bulking effect, and be easily stored and handled. Glutaraldehyde cross-linked bovine collagen (Contigen), silicone polymers (Macroplastique), Durasphere, calcium hydroxyapatite (Coaptite), polyacrylamide hydrogel (Aquamid, Bulkamid), Permacol, and stem cell therapy have been used as injectable agents. Patients must be informed that treatment with injectable agents is not as effective as surgical treatment, and that such agents might necessitate additional and repeated administrations in order to achieve the desired therapeutic effect.

Stress urinary incontinence in women and cell therapy: What can we expect from the future?

Stress urinary incontinence (SUI) is a common disorder that affects a large number of women and their quality of life. The aim of SUI therapy is to restore the existing urethral function via physical therapy, biofeedback, pelvic floor rehabilitation, pharmacological therapy, bulking agents and surgical approaches. Currently, the gold standard for the management of SUI is the tension-free vaginal sling, which provides structural support to the female urethra. However, even minimally invasive surgical procedure such as “slings” carries risks for the patients, lost efficacy over the time and has long-term complications. For this reason, new therapeutic modalities are needed. Cell therapy has been emerged as an alternative to be used on the treatment of different diseases. The use of stem cells as a therapeutic option for SUI is an attractive alternative because, theoretically, injected cells could restore functional muscle cells and aid in sphincter closure in women with sphincter-associated incontinence. This study aims to review the current literature regarding evidences for using stem cell therapy on stress urinary incontinence in women.

Towards a Treatment of Stress Urinary Incontinence: Application of Mesenchymal Stromal Cells for Regeneration of the Sphincter Muscle

Stress urinary incontinence is a significant social, medical, and economic problem. It is caused, at least in part, by degeneration of the sphincter muscle controlling the tightness of the urinary bladder. This muscular degeneration is characterized by a loss of muscle cells and a surplus of a fibrous connective tissue. In Western countries approximately 15% of all females and 10% of males are affected. The incidence is significantly higher among senior citizens, and more than 25% of the elderly suffer from incontinence. When other therapies, such as physical exercise, pharmacological intervention, or electrophysiological stimulation of the sphincter fail to improve the patient’s conditions, a cell-based therapy may improve the function of the sphincter muscle. Here, we briefly summarize current knowledge on stem cells suitable for therapy of urinary incontinence: mesenchymal stromal cells, urine-derived stem cells, and muscle-derived satellite cells. In addition, we report on ways to improve techniques for surgical navigation, injection of cells in the sphincter muscle, sensors for evaluation of post-treatment therapeutic outcome, and perspectives derived from recent pre-clinical studies.

Treatment of experimental esophagogastric myotomy with bone marrow mesenchymal stem cells in a rat model

BACKGROUND

Over the last 15 years, many studies demonstrated the myogenic regenerative potential of bone marrow mesenchymal stem cells (BM-MSC), making them an attractive tool for the regeneration of damaged tissues. In this study, we have developed an animal model of esophagogastric myotomy (MY) aimed at determining the role of autologous MSC in the regeneration of the lower esophageal sphincter (LES) after surgery.

METHODS

Syngeneic BM-MSC were locally injected at the site of MY. Histological and functional analysis were performed to evaluate muscle regeneration, contractive capacity, and the presence of green fluorescent protein-positive BM-MSC (BM-MSC-GFP(+) ) in the damaged area at different time points from implantation.

KEY RESULTS

Treatment with syngeneic BM-MSC improved muscle regeneration and increased contractile function of damaged LES. Transplanted BM-MSC-GFP(+) remained on site up to 30 days post injection. Immunohistochemical analysis demonstrated that MSC maintain their phenotype and no differentiation toward smooth or striated muscle was shown at any time point.

CONCLUSIONS & INFERENCES

Our data support the use of autologous BM-MSC to both improve sphincter regeneration of LES and to control the gastro-esophageal reflux after MY.

[Urinary incontinence in the elderly: what can and should be done?]

The demographic development of society shows a clear increase in the elderly population in the coming decades, which will result in an increasing prevalence of urinary incontinence. Diagnosis and treatment of many patients is not carried out for a myriad of reasons and thus incontinence care is often inadequate. A detailed medical history is the basis of identification of the problem and underpins the effective diagnostic and therapeutic management of the problem. In this context, the algorithms based on the national and international guidelines and age-specific characteristics should be considered. The initial focus should be on conservative management. In a few cases of elderly patients, invasive diagnostics using urodynamics or cystoscopy might be indicated. The increased use of medication in the elderly both from an etiological and therapeutic point of view, especially in terms of drug/drug interactions requires special consideration. In particular cognitive impairment using pharmacological approaches should be avoided. Although incontinence surgery of the patient applies less often with increasing age it still plays a role in the appropriate selection of treatment.

Development of stem cell therapy for stress urinary incontinence

PURPOSE OF REVIEW

In recent years, stem cell therapy has been investigated as a promising approach for the treatment of stress urinary incontinence (SUI). This article reviews the biology of stem cells and their applications as a cell-based treatment for SUI. The current status and future direction of this forefront research in urinary incontinence are also examined.

RECENT FINDINGS

During the past decade, adult stem cells have been studied as a potential cell-based approach for the treatment of SUI. The results of current preclinical and clinical studies are presented. These studies demonstrated the improvement in histologic and functional outcomes with stem cell therapies for SUI. Adult stem cells may augment sphincter regeneration and also release trophic factors, promoting vessel and nerve integration into the generated tissues. So far, the findings of the clinical trials are less impressive than the results obtained with animal studies.

SUMMARY

Although stem cell therapy holds much promise for SUI, the clinical applications in patients have been slow to materialize. This challenge, together with the currently limited data on basic science studies and clinical trials, will undoubtedly stimulate new investigations in the near future.

A nonhuman primate model of stable urinary sphincter deficiency

PURPOSE

The pathophysiology of urinary sphincter deficiency in women remains incompletely understood and current treatment options have limitations. Female nonhuman primates may represent a relevant animal model for studies of pathophysiology and treatment interventions because of their human-like reproductive and age associated stages of life (premenopause, perimenopause and postmenopause), lower urinary tract structure and bipedal posture. We developed and characterized a nonhuman primate model of defined injury to the urethral sphincter complex.

MATERIALS AND METHODS

We used 22 adult female cynomolgus monkeys in which injury to the sphincter complex was created by cauterizing and then transecting its pudendal innervation. Urodynamic studies were performed before and during pudendal and hypogastric nerve stimulation at baseline, and 3, 6 and 12 months after injury. We also analyzed sphincter structure in vivo by cystourethrography, and ex vivo by quantitative histology and immunohistochemistry at these time points.

RESULTS

Injury produced a 47% to 50% decrease in maximal urethral pressure (vs baseline p <0.05). It also abolished the increase in maximal urethral pressure in response to pudendal and hypogastric nerve stimulation (vs baseline p >0.05), which persisted more than 12 months after injury. Urodynamic changes were consistent with decreased skeletal and smooth muscle content, decreased nerve responses and an associated decrease in somatic and adrenergic innervation in the sphincter complex.

CONCLUSIONS

These structural and urodynamic changes are consistent with those in patients with stress urinary incontinence. They support the usefulness of nonhuman primates as translatable surrogates for pathophysiological studies of urinary sphincter deficiency and testing novel therapies for that condition.