Reconstitution of experimental neurogenic bladder dysfunction using skeletal muscle-derived multipotent stem cells. Transplantation. 2010;89:1043-1049. [PMID: 20150836 DOI: 10.1097/tp.0b013e3181d45a7f]

Therapeutic Potential of Mesenchymal Stem Cells in the Treatment of Epilepsy and Their Interaction with Antiseizure Medications

Epilepsy is a life-threatening neurological disease that affects approximately 70 million people worldwide. Although the vast majority of patients may be successfully managed with currently used antiseizure medication (ASM), the search for alternative therapies is still necessary due to pharmacoresistance in about 30% of patients with epilepsy. Here, we review the effects of ASMs on stem cell treatment when they could be, as expected, co-administered. Indeed, it has been reported that ASMs produce significant effects on the differentiation and determination of stem cell fate. In addition, we discuss more recent findings on mesenchymal stem cells (MSCs) in pre-clinical and clinical investigations. In this regard, their ability to differentiate into various cell types, reach damaged tissues and produce and release biologically active molecules with immunomodulatory/anti-inflammatory and regenerative properties make them a high-potential therapeutic tool to address neuroinflammation in different neurological disorders, including epilepsy. Overall, the characteristics of MSCs to be genetically engineered, in order to replace dysfunctional elements with the aim of restoring normal tissue functioning, suggested that these cells could be good candidates for the treatment of epilepsy refractory to ASMs. Further research is required to understand the potential of stem cell treatment in epileptic patients and its interaction with ASMs.

Tissue engineering in reconstructive urology-The current status and critical insights to set future directions-critical review

Advanced techniques of reconstructive urology are gradually reaching their limits in terms of their ability to restore urinary tract function and patients' quality of life. A tissue engineering-based approach to urinary tract reconstruction, utilizing cells and biomaterials, offers an opportunity to overcome current limitations. Although tissue engineering studies have been heralding the imminent introduction of this method into clinics for over a decade, tissue engineering is only marginally applied. In this review, we discuss the role of tissue engineering in reconstructive urology and try to answer the question of why such a promising technology has not proven its clinical usability so far.

Improved bladder contractility after transplantation of human mesenchymal stem cells overexpressing hepatocyte growth factor into underactive bladder from bladder outlet obstruction models of rats

Introduction

An underactive bladder can lead to difficulty in voiding that causes incomplete emptying of the bladder, suggesting the need for a new strategy to increase bladder contractility in such patients. This study was performed to investigate whether human mesenchymal stem cells (hMSCs) were capable of restoring bladder contractility in rats with underactive bladder due to bladder outlet obstruction (BOO) and enhancing their effects by overexpressing hepatocyte growth factor (HGF) in hMSCs.

Materials and methods

The hMSCs were transplanted into the bladder wall of rats. Fifty female Sprague-Dawley rats at six weeks of age were divided into five groups: group 1: control; group 2: sham intervention; group 3: eight-week BOO; group 4: BOO rats transplanted with hMSCs; and group 5: BOO rats transplanted with hMSCs overexpressing HGF. Two weeks after the onset of BOO in groups 4 and 5, hMSCs were injected into the bladder wall. Cystometry evaluation was followed by Masson’s trichrome staining of bladder tissues. Realtime PCR and immunohistochemical staining were performed to determine for hypoxia, apoptosis, and angiogenesis.

Results

Collagen deposition of bladder increased in BOO but decreased after transplantation of hMSCs. The increased inter-contraction interval and residual urine volume after BOO was reversed after hMSCs transplantation. The decreased maximal voiding pressure after BOO was restored by hMSCs treatment. The mRNA expression of bladder collagen1 and TGF-β1 increased in BOO but decreased after hMSCs transplantation. The decrease in vWF-positive cells in the bladder following BOO was increased after hMSCs transplantation. Caspase 3 and TUNEL-positive apoptosis of bladder cells increased in BOO but decreased after transplantation of hMSCs. These effects were enhanced by overexpressing HGF in hMSCs.

Conclusion

Transplantation of hMSCs into bladder wall increased the number of micro-vessels, decreased collagen deposition and apoptosis of detrusor muscle, and improved bladder underactivity. The effects were enhanced by overexpressing HGF in hMSCs. Our findings suggest that the restoration of underactive bladder using hMSCs may be used to rectify micturition disorders in patients following resolution of BOO. Further studies are needed before hMSCs can be used in clinical applications.

Considerations for the clinical use of stem cells in genitourinary regenerative medicine

The genitourinary tract can be affected by several pathologies which require repair or replacement to recover biological functions. Current therapeutic strategies are challenged by a growing shortage of adequate tissues. Therefore, new options must be considered for the treatment of patients, with the use of stem cells (SCs) being attractive. Two different strategies can be derived from stem cell use: Cell therapy and tissue therapy, mainly through tissue engineering. The recent advances using these approaches are described in this review, with a focus on stromal/mesenchymal cells found in adipose tissue. Indeed, the accessibility, high yield at harvest as well as anti-fibrotic, immunomodulatory and proangiogenic properties make adipose-derived stromal/SCs promising alternatives to the therapies currently offered to patients. Finally, an innovative technique allowing tissue reconstruction without exogenous material, the self-assembly approach, will be presented. Despite advances, more studies are needed to translate such approaches from the bench to clinics in urology. For the 21^st century, cell and tissue therapies based on SCs are certainly the future of genitourinary regenerative medicine.

Peripheral Nerve Regeneration Using a Cytokine Cocktail Secreted by Skeletal Muscle-Derived Stem Cells in a Mouse Model

Severe peripheral nerve injury, which does not promise natural healing, inevitably requires clinical treatment. Here, we demonstrated the facilitation effect of peripheral nerve regeneration using a cytokine cocktail secreted by skeletal muscle-derived stem cells (Sk-MSCs). Mouse sciatic nerve was transected with a 6 mm gap and bridged collagen tube, and the culture supernatant of Sk-MSCs with 20% adult mouse serum (AMS)/Iscove’s modified Dulbecco’s medium (IMDM) was administered into the tube immediately after the operation, followed by an injection once a week for six weeks through the skin to the surrounding tube of the cytokine (CT) group. Similarly, 20% AMS/IMDM without cytokines was administered to the non-cytokine control (NT) group. Tension recovery in the plantar flexor muscles via electrical stimulation at the upper portion of the damaged nerve site, as well as the numerical recovery of axons and myelinated fibers at the damaged site, were evaluated as an index of nerve regeneration. Specific cytokines secreted by Sk-MSCs were compared with damaged sciatic nerve-derived cytokines. Six weeks after operation, significantly higher tension output and numerical recovery of the axon and myelinated fibers were consistently observed in the CT group, showing that the present cytokine cocktail may be a useful nerve regeneration acceleration agent. We also determined 17 candidate factors, which are likely included in the cocktail.

Engineered Stem Cells Improve Neurogenic Bladder by Overexpressing SDF-1 in a Pelvic Nerve Injury Rat Model

There is still a lack of sufficient research on the mechanism behind neurogenic bladder (NB) treatment. The aim of this study was to explore the effect of overexpressed stromal cell-derived factor-1 (SDF-1) secreted by engineered immortalized mesenchymal stem cells (imMSCs) on the NB. In this study, primary bone marrow mesenchymal stem cells (BM-MSCs) were transfected into immortalized upregulated SDF-1-engineered BM-MSCs (imMSCs/eSDF-1⁺) or immortalized normal SDF-1-engineered BM-MSCs (imMSCs/eSDF-1⁻). NB rats induced by bilateral pelvic nerve (PN) transection were treated with imMSCs/eSDF-1⁺, imMSCs/eSDF-1⁻, or sham. After a 4-week treatment, the bladder function was assessed by cystometry and voiding pattern analysis. The PN and bladder tissues were evaluated via immunostaining and western blotting analysis. We found that imMSCs/eSDF-1⁺ expressed higher levels of SDF-1 in vitro and in vivo. The treatment of imMSCs/eSDF-1⁺ improved NB and evidently stimulated the recovery of bladder wall in NB rats. The recovery of injured nerve was more effective in the NB+imMSCs/eSDF-1⁺ group than in other groups. High SDF-1 expression improved the levels of vascular endothelial growth factor and basic fibroblast growth factor. Apoptosis was decreased after imMSCs injection, and was detected rarely in the NB+imMSCs/eSDF-1⁺ group. Injection of imMSCs boosted the expression of neuronal nitric oxide synthase, p-AKT, and p-ERK in the NB+imMSCs/eSDF-1⁺ group than in other groups. Our findings demonstrated that overexpression of SDF-1 induced additional MSC homing to the injured tissue, which improved the NB by accelerating the restoration of injured nerve in a rat model.

Current and Future Directions of Stem Cell Therapy for Bladder Dysfunction

Stem cells are capable of self-renewal and differentiation into a range of cell types and promote the release of chemokines and progenitor cells necessary for tissue regeneration. Mesenchymal stem cells are multipotent progenitor cells with enhanced proliferation and differentiation capabilities and less tumorigenicity than conventional adult stem cells; these cells are also easier to acquire. Bladder dysfunction is often chronic in nature with limited treatment modalities due to its undetermined pathophysiology. Most treatments focus on symptom alleviation rather than pathognomonic changes repair. The potential of stem cell therapy for bladder dysfunction has been reported in preclinical models for stress urinary incontinence, overactive bladder, detrusor underactivity, and interstitial cystitis/bladder pain syndrome. Despite these findings, however, stem cell therapy is not yet available for clinical use. Only one pilot study on detrusor underactivity and a handful of clinical trials on stress urinary incontinence have reported the effects of stem cell treatment. This limitation may be due to stem cell function loss following ex vivo expansion, poor in vivo engraftment or survival after transplantation, or a lack of understanding of the precise mechanisms of action underlying therapeutic outcomes and in vivo behavior of stem cells administered to target organs. Efficacy comparisons with existing treatment modalities are also needed for the successful clinical application of stem cell therapies. This review describes the current status of stem cell research on treating bladder dysfunction and suggests future directions to facilitate clinical applications of this promising treatment modality, particularly for bladder dysfunction.

Biomedical applications of muscle-derived stem cells: from bench to bedside

INTRODUCTION

Skeletal muscle-derived stem cells (Sk-MDSCs) are considered promising sources of adult stem cell therapy. Skeletal muscle comprises approximately 40-50% of the total body mass with marked potential for postnatal adaptive response, such as muscle hypertrophy, hyperplasia, atrophy, and regenerative capacity. This strongly suggests that skeletal muscle contains various stem/progenitor cells related to muscle-nerve-vascular tissues, which would support the above postnatal events even in adulthood.

AREA COVERED

The focus of this review is the therapeutic potential of the Sk-MDSCs as an adult stem cell autograft. For this purpose, the validity of cell isolation and purification, tissue reconstitution capacity in vivo after transplantation, comparison of the results of basic mouse and preclinical human studies, potential problematic and beneficial aspects, and effective usage have been discussed following the history of clinical applications.

EXPERT OPINION

Although the clinical application of Sk-MDSCs began as a therapy for the systemic disease of Duchenne muscular dystrophy, here, through the unique local injection method, therapy for severely damaged peripheral nerves, particularly the long-gap nerve transection, has been introduced. The beneficial aspects of the use of Sk-MDSCs as the source of local tissue transplantation therapy have also been discussed.

Verification and Defined Dosage of Sodium Pentobarbital for a Urodynamic Study in the Possibility of Survival Experiments in Female Rat

Objectives

To evaluate the effects of pentobarbital dosages on lower urinary tract function and to define an appropriate dosage of sodium pentobarbital that would be suitable for urodynamic studies in which recovery from anesthesia and long term survive were needed for subsequent experiment.

Methods

Twenty-four 8-week-old, female, virgin, Sprague-Dawley rats (200-250 g) were used in this study. Rats in study groups received gradient doses of pentobarbital intraperitoneally, and those in the control group received urethane intraperitoneally. External urethral sphincter electromyography (EUS-EMG) was recorded simultaneously during cystometry and leak point pressure tests. The toe-pinch reflex was used to determine the level of anesthesia.

Results

Micturition was normally induced in both the urethane group and 32 mg/kg pentobarbital group. However, in groups of 40 mg/kg or 36 mg/kg pentobarbital, micturition failed to be induced; instead, nonvoiding contractions accompanied by EUS-EMG tonic activity were observed. There were no significant differences in leak point pressure or EUS-EMG amplitude or frequency between the urethane and 32 mg/kg pentobarbital groups.

Conclusions

This study confirmed significant dose-dependent effects of pentobarbital on lower urinary tract function and 32 mg/kg pentobarbital as an appropriate dosage for recovery urodynamic testing, which enable the achievement of expected essential micturition under satisfactory anesthesia in female rats.

Can bladder shear wave elastography be an alternative method for detection of neurogenic bladder instead of urodynamic study?

Background:

In the normal physiology of the bladder wall, it has sufficient elasticity so that it can maintain normal pressure during filling phase of bladder. Bladder functional pathology can cause many problems for patients.

Method:

This evaluation is a cross-sectional study conducted on patients suspected of neurogenic bladder. In this study, patient refered for urodynamic testing at first, urodynamic test performed by urologist and then Shear wave elastography was performed by radiologist. Data such as age, sex, height, and weight, and other demographic data were also evaluated. Patients were informed before and after the urodynamic and Shear wave sonography tests. Finally, the data were entered into SPSS software and were statistically analyzed.

Results:

We observed that the mean and standard deviation of the age was 15.7 ± 6.2 years. Also found that in gender 19 (63.3%) patients were males and 11 (36.7%) were female. On the other hand, in terms of BMI, most patients were normal in this regard (50%), as well as in other cases, including weight loss in 3 (10%) patients, overweight in 8 (26.6%) patients, and obese were in 4 patients (13.3%). in our assessment about the efficacy of the ultrasound elastography approach to the anterior wall, which showed that the specificity of the test in the diagnosis of neurogenic bladder was 83% and this is statistically significant in patients (P < 0.05). We also observed in the posterior wall posture that the specificity of this test was 85% in the diagnosis of neurogenic bladder, which indicates a high diagnostic capability of this test, and this is statistically significant in patients (P < 0.05).

Conclusion:

Based on the results observed in this evaluation, ultrasound elastography has a high specificity for neurogenic bladder detection in comparison with urodynamic study. Accordingly, due to the less invasive nature of this method than urodynamic study, this method can be used to identify patients with neurogenic bladder.

Regeneration of Transected Recurrent Laryngeal Nerve Using Hybrid-Transplantation of Skeletal Muscle-Derived Stem Cells and Bioabsorbable Scaffold

Hybrid transplantation of skeletal muscle-derived multipotent stem cells (Sk-MSCs) and bioabsorbable polyglyconate (PGA) felt was studied as a novel regeneration therapy for the transected recurrent laryngeal nerve (RLN). Sk-MSCs were isolated from green fluorescence protein transgenic mice and then expanded and transplanted with PGA felt for the hybrid transplantation (HY group) into the RLN transected mouse model. Transplantation of culture medium (M group) and PGA + medium (PGA group) were examined as controls. After eight weeks, trans-oral video laryngoscopy demonstrated 80% recovery of spontaneous vocal-fold movement during breathing in the HY group, whereas the M and PGA groups showed wholly no recoveries. The Sk-MSCs showed active engraftment confined to the damaged RLN portion, representing favorable prevention of cell diffusion on PGA, with an enhanced expression of nerve growth factor mRNAs. Axonal re-connection in the HY group was confirmed by histological serial sections. Immunohistochemical analysis revealed the differentiation of Sk-MSCs into Schwann cells and perineurial/endoneurial cells and axonal growth supportive of perineurium/endoneurium. The number of axons recovered was over 86%. These results showed that the stem cell and cytokine delivery system using hybrid transplantation of Sk-MSCs/PGA-felt is a potentially practical and useful approach for the recovery of transected RLN.

Current concepts of the acontractile bladder

The acontractile bladder (AcB) is a urodynamic-based diagnosis wherein the bladder is unable to demonstrate any contraction during a pressure flow study. Although it is often grouped with underactive bladder, it is a unique phenomenon and should be investigated independently. The purpose of the present review was to examine the current literature on AcB regarding its pathology, diagnosis, current management guidelines, and future developments. We performed a review of the PubMed database, classifying the evidence for AcB pathology, diagnosis, treatment, and potential future treatments. Over the 67 years covered in our review period, 42 studies were identified that met our criteria. Studies were largely poor quality and mainly consisted of retrospective review or animal models. The underlying pathology of AcB is variable with both neurological and myogenic aetiologies. Treatment is largely tailored for renal preservation and reduction of infection. Although future developments may allow more functional restorative treatments, current treatments mainly focus on bladder drainage. AcB is a unique and understudied bladder phenomenon. Treatment is largely based on symptoms and presentation. While cellular therapy and neuromodulation may hold promise, further research is needed into the underlying neuro-urological pathophysiology of this disease so that we may better develop future treatments.

Stem Cell Therapy for Male Urinary Incontinence

INTRODUCTION

Among the medical and surgical options which have been proposed in the last years for the management of male stress urinary incontinence (SUI), stem cell therapy represents a new frontier 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.

MATERIAL AND METHODS

A PubMed review of the literature on stem cell therapy for the treatment of male SUI was performed.

RESULTS

Regarding animal studies, bone marrow-, muscle- and adipose-derived stem cells have been widely studied, showing regeneration of the urethral sphincter and recovery of the damaged pelvic nerves. With regard to human studies, only four papers are available in the literature using muscle- and adipose-derived stem cells which reported a significant improvement in sphincteric function and incontinence with no severe side effects.

CONCLUSIONS

In spite of these promising results, further studies are needed with longer follow-ups and larger numbers of patients in order to clarify the potential role of stem cell therapy for the treatment of male SUI.

Reconstruction of Multiple Facial Nerve Branches Using Skeletal Muscle-Derived Multipotent Stem Cell Sheet-Pellet Transplantation

Head and neck cancer is often diagnosed at advanced stages, and surgical resection with wide margins is generally indicated, despite this treatment being associated with poor postoperative quality of life (QOL). We have previously reported on the therapeutic effects of skeletal muscle-derived multipotent stem cells (Sk-MSCs), which exert reconstitution capacity for muscle-nerve-blood vessel units. Recently, we further developed a 3D patch-transplantation system using Sk-MSC sheet-pellets. The aim of this study is the application of the 3D Sk-MSC transplantation system to the reconstitution of facial complex nerve-vascular networks after severe damage. Mouse experiments were performed for histological analysis and rats were used for functional examinations. The Sk-MSC sheet-pellets were prepared from GFP-Tg mice and SD rats, and were transplanted into the facial resection model (ST). Culture medium was transplanted as a control (NT). In the mouse experiment, facial-nerve-palsy (FNP) scoring was performed weekly during the recovery period, and immunohistochemistry was used for the evaluation of histological recovery after 8 weeks. In rats, contractility of facial muscles was measured via electrical stimulation of facial nerves root, as the marker of total functional recovery at 8 weeks after transplantation. The ST-group showed significantly higher FNP (about three fold) scores when compared to the NT-group after 2–8 weeks. Similarly, significant functional recovery of whisker movement muscles was confirmed in the ST-group at 8 weeks after transplantation. In addition, engrafted GFP⁺ cells formed complex branches of nerve-vascular networks, with differentiation into Schwann cells and perineurial/endoneurial cells, as well as vascular endothelial and smooth muscle cells. Thus, Sk-MSC sheet-pellet transplantation is potentially useful for functional reconstitution therapy of large defects in facial nerve-vascular networks.

Stem cell applications for pathologies of the urinary bladder

New stem cell based therapies are undergoing intense research and are widely investigated in clinical fields including the urinary system. The urinary bladder performs critical complex functions that rely on its highly coordinated anatomical composition and multiplex of regulatory mechanisms. Bladder pathologies resulting in severe dysfunction are common clinical encounter and often cause significant impairment of patient’s quality of life. Current surgical and medical interventions to correct urinary dysfunction or to replace an absent or defective bladder are sub-optimal and are associated with notable complications. As a result, stem cell based therapies for the urinary bladder are hoped to offer new venues that could make up for limitations of existing therapies. In this article, we review research efforts that describe the use of different types of stem cells in bladder reconstruction, urinary incontinence and retention disorders. In particular, stress urinary incontinence has been a popular target for stem cell based therapies in reported clinical trials. Furthermore, we discuss the relevance of the cancer stem cell hypothesis to the development of bladder cancer. A key subject that should not be overlooked is the safety and quality of stem cell based therapies introduced to human subjects either in a research or a clinical context.

Potential of stem cell treatment in detrusor dysfunction

The current treatments of bladder dysfunctions, such as bladder overactivity and impaired ability to empty, have limitations, and new treatment alternatives are needed. Stem cell transplantation and tissue engineering have shown promising results in preclinical studies. Stem cells were originally thought to act by differentiating into various cell types, thereby replacing damaged cells and restoring functional deficits. Even if such a mechanism cannot be excluded, the current belief is that a main action is exerted by the stem cells secreting bioactive factors that direct other stem cells to the target organ. In addition, stem cells may exert a number of other effects that can improve bladder dysfunction, since they may have antiapoptotic, antifibrotic, and immunomodulatory properties, and can induce neovascularization. Tissue engineering for bladder replacement, which has had varying success in different animal species, has reached the proof-of-concept state in humans, but recent research suggests that the present approaches may not be optimal. Further studies on new approaches, using animal models with translational predictability, seem necessary for further progress.

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.

Regeneration of degenerated urinary sphincter muscles: improved stem cell-based therapies and novel imaging technologies

Stress urinary incontinence (SUI) is a largely ousted but significant medical, social, and economic problem. Surveys suggest that nowadays approximately 10% of the male and 15% of the female population suffer from urinary incontinence at some stage in their lifetime. In women, two major etiologies contribute to SUI: degeneration of the urethral sphincter muscle controlling the closing mechanism of the bladder outflow and changes in lower pelvic organ position associated with degeneration of connective tissue or with mechanical stress, including obesity and load and tissue injury during pregnancy and delivery. In males, the reduction of the sphincter muscle function is sometimes due to surgical interventions as a consequence of prostate cancer treatment, benign prostate hyperplasia, or of neuropathical origin. Accordingly, for women and men different therapies were developed. In some cases, SUI can be treated by physical exercise, electrophysiological stimulation, and pharmacological interventions. If this fails to improve the situation, surgical interventions are required. In standard procedures, endoprostheses for mechanical support of the weakened tissue or mechanical valves for a bladder outflow control are implanted. In 20% of cases treated, repeat procedures are required as implants yield all sorts of side effects in time. Based on preclinical studies, the application of an advanced therapy medicinal product (ATMP) such as implantation of autologous cells may be a curative and long-lasting therapy for SUI. Cellular therapy could also be an option for men suffering from incontinence caused by injury of the nerves controlling the muscular sphincter system. Here we briefly report on human progenitor cells, especially on mesenchymal stromal cells (MSCs), their expansion and differentiation to smooth muscle or striated muscle cells in vitro, labeling of cells for in vivo imaging, concepts of improved, precise, yet gentle application of cells in muscle tissue, and monitoring of injected cells in situ.

Bridging long gap peripheral nerve injury using skeletal muscle-derived multipotent stem cells

Long gap peripheral nerve injuries usually reulting in life-changing problems for patients. Skeletal muscle derived-multipotent stem cells (Sk-MSCs) can differentiate into Schwann and perineurial/endoneurial cells, vascular relating pericytes, and endothelial and smooth muscle cells in the damaged peripheral nerve niche. Application of the Sk-MSCs in the bridging conduit for repairing long nerve gap injury resulted favorable axonal regeneration, which showing superior effects than gold standard therapy--healthy nerve autograft. This means that it does not need to sacrifice of healthy nerves or loss of related functions for repairing peripheral nerve injury.

In vivo determination of muscle-derived stem cells in the rat corpus cavernosum

The aim of the present in vivo study was to determine the presence of muscle-derived stem cells (MDSCs) in the corpus cavernosum of rats. Immunohistochemistry and reverse transcription polymerase chain reaction (RT-PCR) were performed to detect the expression of the stem cell markers stem cell antigen-1 (Sca-1), Oct4 and Desmin in Sprague-Dawley rats aged 2, 5 and 20 months. Sca-1 was mainly expressed in the blood vessels and cavernous sinus and staining revealed that Sca-1 was predominantly expressed in the cytoplasm. Desmin was primarily expressed in muscular tissues and staining demonstrated that it was mainly expressed in the cytoplasm, however, Desmin was also partially expressed in the nuclei. A small number of double positive cells, expressing Sca-1 and Desmin, were also detected near the cavernous sinus. It was found that the expression of the markers was negatively correlated with the age of the rats (P<0.05). The results from the RT-PCR demonstrated that the expression levels of Sca-1 and Desmin significantly decreased with age (P<0.05). In addition, the correlation analysis indicated that the expression of Sca-1 and Desmin were negatively correlated with the age of the rats (r=−−0.929; P<0.05). In conclusion, the present study provided evidence for the presence of MDSCs in the rat corpus cavernosum. MDSCs may be a potential therapeutic treatment for organic erectile dysfunction.

Treatment of bladder dysfunction using stem cell or tissue engineering technique

Tissue engineering and stem cell transplantation are two important options that may help overcome limitations in the current treatment strategy for bladder dysfunction. Stem cell therapy holds great promise for treating pathophysiology, as well as for urological tissue engineering and regeneration. To date, stem cell therapy in urology has mainly focused on oncology and erectile dysfunction. The therapeutic potency of stem cells (SCs) was originally thought to derive from their ability to differentiate into various cell types including smooth muscle. The main mechanisms of SCs in reconstituting or restoring bladder function are migration, differentiation, and paracrine effects. Nowadays, paracrine effects of stem cells are thought to be more prominent because of their stimulating effects on stem cells and adjacent cells. Studies of stem cell therapy for bladder dysfunction have been limited to experimental models and have been less focused on tissue engineering for bladder regeneration. Bladder outlet obstruction is a representative model. Adipose-derived stem cells, bone marrow stem cells (BMSCs), and skeletal muscle-derived stem cells or muscle precursor cells are used for transplantation to treat bladder dysfunction. The aim of this study is to review stem cell therapy and updated tissue regeneration as treatments for bladder dysfunction and to provide the current status of stem cell therapy and tissue engineering for bladder dysfunction including its mechanisms and limitations.

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.

Isolation and passage of muscle-derived stem cells from the rat penile corpora cavernosa and induction of differentiation into smooth muscle cells

This study treated the isolation and passage of muscle-derived stem cells (MDSCs) from rat penile corpora cavernosa, detection of stem cell marker expression, observation of their self-renewal and continuous proliferation, and demonstration of their potential to differentiate into smooth muscle cells in co-culture. Muscle-derived stem cells from the rat penile corpora cavernosa were isolated and purified. The expression of stem cell markers Sca-1 and desmin was detected in PP6 cells, thus confirming that the main components of PP6 cells are MDSCs. The expression of Sca-1 and desmin occurred both in PP6 cells and cells at passages 3, 6, and 8, and there was no significant decrease in the expression level with increasing passage number. The growth curves indicated that the cell doubling time was approximately 48 h. The cells entered the stationary phase after approximately 7 days of culture. The proliferative activity of the cells at passage 8 remained unchanged. After 2 days of co-culture with smooth muscle cells, the DAPI-labeled MDSCs tended to exhibit smooth muscle cell morphology and expression of α-SMA was detected. MDSCs exist in the rat penile corpora cavernosa and possess the potential to differentiate into smooth muscle cells. This discovery serves as the basis in view of the potential use of endogenous stem cells for the treatment of erectile dysfunction (ED).

Adipose-derived stem cells (ADSCs) and muscle precursor cells (MPCs) for the treatment of bladder voiding dysfunction

PURPOSE

Bladder outflow obstruction (BOO) is common in the elderly and can result in bladder voiding dysfunction (BVD) due to severe bladder muscle damage. The goal of this research was to evaluate the use of adult stem cells for the treatment of BVD due to decreased muscle contractility in a rat model.

MATERIALS AND METHODS

Adipose-derived stem cells (ADSCs) and muscle precursor cells (MPCs) were harvested from male Lewis rats and expanded in culture. BOO was induced by tying a suture around the urethra. Six weeks after obstruction, the development of BVD was confirmed by cystometric analysis in conscious rats, histology and molecular investigations. Injection of ADSCs or MPCs into the bladder wall and synchronous deligation was performed 6 weeks after the obstruction. After stem-cell treatment, morphological and functional changes were assessed. Age-matched rats and animals without cellular therapy but deligation-only served as controls.

RESULTS

Voiding pressures decreased progressively 6 weeks after obstruction with increased bladder capacities. Structural changes of the detrusor muscle occurred during the time of obstruction with an increased connective tissue-to-smooth muscle ratio and decreased SMA/smoothelin expression. After stem-cell injection, improved voiding pressures and voiding volumes were observed together with recovered tissue architecture. RT-PCR and Western blotting showed an up-regulation of important contractile proteins.

CONCLUSIONS

We established a reliable model for BVD and demonstrated that ADSCs and MPCs can prevent pathophysiological remodelling and provide regenerated bladder tissue and function.

Stem cell therapy in bladder dysfunction: where are we? And where do we have to go?

To date, stem cell therapy for the bladder has been conducted mainly on an experimental basis in the areas of bladder dysfunction. The therapeutic efficacy of stem cells was originally thought to be derived from their ability to differentiate into various cell types. Studies about stem cell therapy for bladder dysfunction have been limited to an experimental basis and have been less focused than bladder regeneration. Bladder dysfunction was listed in MESH as "urinary bladder neck obstruction", "urinary bladder, overactive", and "urinary bladder, neurogenic". Using those keywords, several articles were searched and studied. The bladder dysfunction model includes bladder outlet obstruction, cryoinjured, diabetes, ischemia, and spinal cord injury. Adipose derived stem cells (ADSCs), bone marrow stem cells (BMSCs), and skeletal muscle derived stem cells (SkMSCs) are used for transplantation to treat bladder dysfunction. The main mechanisms of stem cells to reconstitute or restore bladder dysfunction are migration, differentiation, and paracrine effects. The aim of this study is to review the stem cell therapy for bladder dysfunction and to provide the status of stem cell therapy for bladder dysfunction.

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.

Stem cell therapy for stress urinary incontinence: a critical review

Stress urinary incontinence (SUI) is a prevailing health problem that severely impacts quality of life. Because SUI is mainly due to urethral sphincter deficiency, several preclinical and clinical trials have investigated whether transplantation of patient's own skeletal muscle-derived cells (SkMDCs) can restore the sphincter musculature. The specific cell type of SkMDCs has been described as myoblasts, satellite cells, muscle progenitor cells, or muscle-derived stem cells, and thus may vary from study to study. In more recent years, other stem cell (SC) types have also been tested, including those from the bone marrow, umbilical cord blood, and adipose tissue. These studies were mostly preclinical and utilized rat SUI models that were established predominantly by pudendal or sciatic nerve injury. Less frequently used animal models were sphincter injury and vaginal distension. While transurethral injection of SCs was employed almost exclusively in clinical trials, periurethral injection was used in all preclinical trials. Intravenous injection was also used in one preclinical study. Functional assessment of therapeutic efficacy in preclinical studies has relied almost exclusively on leak point pressure measurement. Histological assessment examined the sphincter muscle content, existence of transplanted SCs, and possible differentiation of these SCs. While all of these studies reported favorable functional and histological outcomes, there are questions about the validity of the animal model and claims of multilineage differentiation. In any event, SC transplantation appears to be a promising treatment for SUI.

Clinical observation on the acupuncture treatment in patients with urinary retention after radical hysterectomy

OBJECTIVE

To observe the acupuncture therapy effect on the urinary retention after radical: hysterectomy. METHODS METHODS: Eighty cases of urinary retention after radical hysterectomy were randomly assigned to: the treatment group and control group according to the random number table method, 40 cases in each group. From the 15th day post operation, the patients in the two groups started to be treated and 7 days as a course with 5 days treatment and 2 days interval. The treatment group applied acupuncture with modalities of common needling on Zusanli (ST36) bilaterally, electroacupuncture on Sanyinjiao (SP6), Shuidao (ST28), and Scalp Reproduction Area bilaterally, moxibustion on Shenque (CV8). The control group applied acupoint injection with vitamin B B12 12, and Sanyinjiao and Zusanli were selected. Take turns on both sides. The courses for the recovery, of bladder function and residual urine volume for those who had voluntary micturition more than 200 mL after the first and second course of treatment were compared between the two groups.

RESULTS

Within 1 course and 2: courses of treatment, the patients with bladder function recovery in the treatment group were 21 (21/40) and 36 (36/40), and those in the control group were 12 (12/40) and 29 (29/40), both with a significant difference (P<0.05). After the first course and second course, residual urine volume for those who had voluntary micturition more than 200 mL in the treatment group was 91.7 ± 17.5 mL and 93.5 ± 15.5 mL, in the control group 102.4 ± 13.7 mL and 102.5 ± 15.7 mL, both with a significant difference (P<0.05).

CONCLUSIONS

Combination of acupuncture: modalities was better than acupoint injection for the recovery of bladder function in urinary retention after radical hysterectomy. It would shorten the course of treatment and get a better recovery, decrease urinary retention cases of refractoriness, and extending the treatment could raise the healing rate of urinary retention.

Stem cells for the treatment of urinary incontinence

Stress urinary incontinence (SUI) is highly prevalent. As of now, there is no minimally invasive long-term treatment available. Adult stem cells are nonimmunogenic and have the ability to self-renew and to differentiate into multiple cell types. Over the past decade, in vivo studies have described periurethral injections of adult-derived stem cells for the treatment of SUI. The ultimate goal has been to achieve a permanent cure for SUI by restoration of the intrinsic and extrinsic urethral sphincter and the surrounding connective tissue, including peripheral nerves and blood vessels. For this purpose, future studies need to focus on delivery systems, cell survival, and functional improvement of the urethral closure mechanism, including improvement of innervation and vascularization.