Stem Cell Therapy for Erectile Dysfunction

Interrogating erectile dysfunction and evaluating novel therapeutic frontiers, with emphasis on stem cell strategies

Male infertility arises from a complex interplay of factors affecting reproductive organs and various physiological pathways. Among these, erectile dysfunction (ED), a widespread global issue, plays a key role. While existing ED treatments address some aspects, achieving complete reversibility and avoiding side effects remains a challenge. In this context, stem cell therapy emerges as a promising, potentially transformative approach. Preliminary evidence from preclinical animal models and clinical trials highlights stem cell therapy's remarkable efficacy and effectiveness for ED. This novel strategy offers several advantages, including enhanced effectiveness and a reported absence of adverse side effects. This review delves into the causes of male infertility, with a particular focus on ED and its pathophysiology. We explore the current treatment landscape, highlighting therapy's existing strategies' limitations and stem cell therapy's unique potential. By examining relevant preclinical and clinical studies, we provide a comprehensive picture of this innovative approach and its promising future in restoring men's fertility and quality of life.

Stem cell therapy in diabetic men with erectile dysfunction: a 24-month follow-up of safety and efficacy of two intracavernous autologous bone marrow derived mesenchymal stem cells injections, an open label phase 2 clinical trial

BACKGROUND

Recently we reported results of phase 1 pilot clinical trial of 2 consecutive intracavernous (IC) injection of autologous bone marrow-derived mesenchymal stem cells (BM-MSCs) for the first time in the treatment of diabetic patients with erectile dysfunction (DM-ED). In phase 2 of this study our aim is to evaluate long term safety and efficacy of IC injections of BM-MSC on additional eight patients with DM-ED.

RESULTS

Each patient received 2 consecutive IC injections of BM-MSC and evaluated at 1, 3, 6, 12, and 24-month time points. Primary outcome was the tolerability and safety of stem cells therapy (SCT), while the secondary outcome was improvement of erectile function (EF) as assessed using the International Index of Erectile Function-5 (IIEF-5), Erection Hardness Score (EHS) questionnaires, and Color Duplex Doppler Ultrasound (CDDU). IC injections of BM-MSCs was safe and well-tolerated. Minor local and short-term adverse events related to the bone marrow aspiration and IC injections were observed and treated conservatively. There were significant improvement in mean IIEF-5, EHS, all over the follow-up time points in comparison to the baseline. At 24-month follow up there were significant decline in the mean IIEF-5, and EHS compared to the baseline. The mean basal and 20-min peak systolic velocity was significantly higher at 3-month after the IC injections compared to baseline.

CONCLUSIONS

This phase 2 clinical trial confirmed that IC injections of BM-MSC are safe and improve EF. The decline in EF over time suggests a need for assessing repeated injections.

CLINICAL TRIAL REGISTRATION

NCT02945462.

Research Advances in Stem Cell Therapy for Erectile Dysfunction

Erectile dysfunction (ED) is a common clinical condition that mainly affects men aged over 40 years. Various causes contribute to the progression of ED, including pelvic nerve injury, diabetes, metabolic syndrome, age, Peyronie's disease, smoking, and psychological disorders. Current treatments for ED are limited to symptom relief and do not address the root cause. Stem cells, with their powerful ability to proliferate and differentiate, are a promising approach for the treatment of male ED and are gradually gaining widespread attention. Current uses for treating ED have been studied primarily in experimental animals, with most studies observing improvements in erectile quality as well as improvements in erectile tissue. However, research on stem cell therapy for human ED is still limited. This article summarizes the recent literature on basic stem cell research on ED, including cavernous nerve injury, aging, diabetes, and sclerosing penile disease, and describes mechanisms of action and therapeutic effects of various stem cell therapies in experimental animals. Stem cells are also believed to interact with host tissue in a paracrine manner, and improved function can be supported through both implantation and paracrine factors. To date, stem cells have shown some preliminary promising results in animal and human models of ED.

Bibliometric and Visualization Analysis of Stem Cell Therapy for Erectile Dysfunction

Purpose

As a common male disease, erectile dysfunction (ED) seriously affects the physical and mental health of patients. In recent years, studies have continued to point out the great potential of stem cell therapy (SCT) in the treatment of ED. The purpose of this study is to comprehensively analyze the research of SCT for ED and understand the development trends and research frontiers in this field.

Methods

Publications regarding SCT and ED were retrieved and collected from the Web of Science Core Collection. CiteSpace and VOSviewer software were then utilized for bibliometric and visualization analysis.

Results

A total of 524 publications were eventually included in this study. The annual number of publications in this field was increasing year by year. China and the USA were the two most productive countries. Lin GT, Lue TF and Lin CS, and the University of California San Francisco where they worked were the most productive research group and institution, respectively. The journal with the largest number of publications was The Journal of Sexual Medicine, and the following were mostly professional journals of urology and andrology. Diabetes mellitus-induced ED and cavernous nerve injury-related ED were the two most commonly constructed models of ED in studies. Concerning the types of stem cells, mesenchymal stem cells derived from adipose and bone marrow were most frequently used. Moreover, future research would mainly focus on exosomes, tissue engineering technology, extracorporeal shockwave therapy, and clinical translation.

Conclusion

The research of SCT for ED will receive increasing global attention in the future. Our study provided bibliometric and visualization analysis of published literature, helping researchers understand the global landscape and frontiers in this field. More preclinical and clinical studies should be conducted to more deeply explore the underlying mechanisms of treatment and promote clinical translation.

Adipose Derived Mesenchymal Stem Cells-Derived Mitochondria Transplantation Ameliorated Erectile Dysfunction Induced by Cavernous Nerve Injury

PURPOSE

Erectile dysfunction (ED) is a common postoperative complication of pelvic surgery for which there is currently no effective treatment. This study investigated the therapeutic effects and potential mechanisms of adipose derived mesenchymal stem cells-derived mitochondria (ADSCs-mito) transplantation in a rat model of bilateral cavernous nerve injury (CNI) ED.

MATERIALS AND METHODS

We isolated mitochondria from ADSCs and tested their quality. In vivo, twenty male Sprague Dawley rats were randomly divided into four groups: sham operation group and CNI groups that received intracavernous injection of either phosphate buffer solution, ADSCs-mito or ADSCs. Two weeks after therapy, the erectile function of the rats was evaluated and the penile tissues were harvested for histologic analysis and western blotting. In vitro, the apoptosis rate, reactive oxygen species (ROS), mitochondria derived active oxygen (mtROS) and adenosine triphosphate (ATP) levels were detected in corpus cavernosum smooth muscle cells (CCSMCs) after the incubation with ADSCs-mito. In addition, intercellular mitochondrial transfer was visualized by co-culture of ADSCs and CCSMCs.

RESULTS

The ADSCs, ADSCs-mito and CCSMCs were isolated and identified successfully. ADSCs-mito transplantation notably restored the erectile function and smooth muscle content of CNI ED rats. Moreover, the levels of ROS, mtROS and cleaved-caspase 3 were reduced and the levels of superoxide dismutase and ATP were increased after ADSCs-mito transplantation. In CNI ED rats, the mitochondrial structure of cells in penile tissues was destroyed. ADSCs could transfer its own mitochondria to CCSMCs. Pre-treatment with ADSCs-mito could significantly decrease apoptosis rate, ROS levels and mtROS levels as well as restore the ATP level in CCSMCs.

CONCLUSIONS

ADSCs-mito transplantation significantly ameliorated ED induced by CNI, with similar potency to ADSCs treatment. The ADSCs-mito might exert their effects via anti-oxidative stress, anti-apoptosis and modulating energy metabolism of CCSMCs. Mitochondrial transplantation should be a promising therapeutic method for treating CNI ED in the future.

Stem cell therapy for erectile dysfunction: a systematic review

INTRODUCTION

Erectile dysfunction (ED) is a common condition that negatively affects men's quality of life. It can have various causes, including psychological, vascular, and neurologic factors. Existing treatments for ED mainly focus on symptom relief rather than addressing the underlying cause. Stem cells (SCs) have shown potential as a therapeutic approach for ED due to their anti-inflammatory properties.

OBJECTIVES

This systematic review aims to assess the current status of trials and determine the potential impact of SCs on male sexual health.

METHODS

A comprehensive search strategy was employed to gather relevant articles from 6 electronic databases. The search included articles published until March 2023. The reference lists of articles were manually reviewed to identify additional studies of relevance. The eligibility criteria for inclusion in the analysis focused on clinical trials involving humans that evaluated the safety and efficacy of SC therapy for ED. Exclusion criteria encompassed case reports, case series, abstracts, reviews, and editorials, as well as studies involving animals or SC derivatives. Data extraction was performed via a standardized form with a focus on erectile outcomes.

RESULTS

A total of 2847 articles were initially identified; 18 were included in the final analysis. These studies involved 373 patients with ED and various underlying medical conditions. Multiple types of SC were utilized in the treatment of ED: mesenchymal SCs, placental matrix-derived mesenchymal SCs, mesenchymal SC-derived exosomes, adipose-derived SCs, bone marrow-derived mononuclear SCs, and umbilical cord blood SCs.

CONCLUSION

SC therapy shows promise as an innovative and safe treatment for organic ED. However, the lack of standardized techniques and controlled groups in many studies hampers the ability to evaluate and compare trials.

Efficacy of L-arginine and Pycnogenol ® in the treatment of male erectile dysfunction: a systematic review and meta-analysis

Background

The objective of this meta-analysis was to review clinical trials of the combination of Pycnogenol ® and L-arginine (PAL) in the treatment of erectile dysfunction in men and to observe the effect of PAL combined therapy on sexual function in patients with erectile dysfunction (ED), and we hope to provide more choices of drugs for treating patients with ED.

Methods and analysis

The study was constructed according to the Preferred Reporting Items for Systematic Reviews and Meta-Analysis guidelines. We searched seven databases from inception to 15 February 2023, for a comprehensive search of clinical trials using relevant keywords. Continuous variables in this meta-analysis were calculated using the mean difference and 95% confidence interval. All relevant statistical analyses were performed using RevMan v. 5.4 software.

Results

Three studies with 184 patients were included in the present meta-analysis. There were no significant differences in the basic characteristics of the included studies. The results of the current meta-analysis showed that there were significant differences in the international index of erectile function scores (erectile domain), intercourse satisfaction scores, orgasmic function scores, overall satisfaction scores, and sexual desire scores between the combination treatment group and the control group. There was no significant difference in improving the testosterone levels between the two groups.

Conclusion

These results indicate that the combination of PAL may have a significant effect on improving sexual function in patients with mild to moderate ED. This study will provide clinicians with more options for treating patients with ED. More randomized controlled trials are needed in the future to further demonstrate the effect of combination therapy on sexual function in patients with ED.

Systematic review registration

https://www.crd.york.ac.uk/PROSPERO/#myprosperoUnique, Identifier: CRD42023411781.

Stem-Cell, Shockwave, and Platelet Rich Plasma Therapy for the Treatment of Erectile Dysfunction and Peyronie's Disease: A Survey of Clinics Across the USA

OBJECTIVE

To identify clinics offering off-label therapies for erectile dysfunction (ED) and Peyronie's disease (Pyd) including stem cell, platelet-rich plasma (PRP), and shockwave therapy and to determine the transparency they provided to patients inquiring about these treatment modalities.

METHODS

Clinics were identified in different regions in the US using a systematic search on online website directories and were approached by asking a series of standardized questions regarding the cost of treatment, duration of therapy, the medical staff involved, and patient outcome data. A total of 26 clinics were surveyed for stem cell therapy, 26 for PRP treatment, and 27 for shockwave therapy.

RESULTS

Of the 79 clinics contacted, 93.7% provided some answers to the questions we asked, with a majority offering treatments for both ED and Pyd. The cost of treatment varied widely between clinics. The average cost per stem cell therapy injection was $5291, PRP per injection was $1336, and shockwave therapy per session was $413. A physician was involved in 67% of treatments, and only 6 of 79 clinics reported that a urologist was involved. Over 75% of the clinics reported patient satisfaction following treatment. Durability of benefits to patients ranged from months to years according to the clinics' reports.

CONCLUSION

Our data not only demonstrate the widespread use of off-label therapies for ED and PyD across the United States but also the lack of scientific data to support the claims made to patients. This study highlights the need for more oversight and standardization in novel regenerative therapies for ED and PyD.

Causal association between JAK2 and erectile dysfunction: a Mendelian randomization study

BACKGROUND

As one of the most critical proteins in the JAK/STAT signaling pathway, Janus kinase 2 (JAK2) is involved in many biological processes and diseases. Several observational studies have reported the role of JAK2 in erectile dysfunction. However, the causal relationship between JAK2 and erectile dysfunction remains unclear. Here we investigated the causal relationship between JAK2 and erectile dysfunction.

RESULTS

Genetically predicted JAK2 was causally associated with erectile dysfunction in inverse variance weighting (OR = 1.109, 95% CI = 1.029-1.196, p = 0.007) and weighted median method (OR = 1.117, 95% CI = 1.003-1.245, p = 0.044). No heterogeneity was observed in Cochran Q-test (p = 0.855) and MR-PRESSO (p = 0.866). Pleiotropy was not observed in our study (p = 0.617).

CONCLUSIONS

These findings highlighted JAK2 as a risk factor for erectile dysfunction and proved the causal relationship between JAK2 and erectile dysfunction, suggesting that targeting JAK2 signaling might be a novel and promising therapeutic candidate in the treatment of erectile dysfunction.

Erectile Dysfunction Treatment Using Stem Cell Delivery Patch in a Cavernous Nerve Injury Rat Model

Erectile dysfunction (ED) is a common and feared complication of radical prostatectomy (RP) for prostate cancer. Recently, tissue engineering for post-prostatectomy ED has been attempted in which controlled interactions between cells, growth factors, and the extracellular matrix (ECM) are important for the structural integrity if nerve regeneration. In this study, we evaluated the effects of a biomechanical ECM patch on the morphology and behavior of human bone marrow-derived mesenchymal stem cells (hBMSCs) in a bilateral cavernous nerve injury (BCNI) rat model. The ECM patch, made of decellularized human fibroblast-derived ECM (hFDM) and a biocompatible polyvinyl alcohol (PVA) hydrogel, was tested with human bone marrow-derived mesenchymal stem cells (hBMSCs) on a bilateral cavernous nerve injury (BCNI) rat model. In vitro analysis showed that the hFDM/PVA + hBMSCs patches significantly increased neural development markers. In vivo experiments demonstrated that the rats treated with the hFDM/PVA patch had higher ICP/MAP ratios, higher ratios of smooth muscle to collagen, increased nNOS content, higher levels of eNOS protein expression, and higher cGMP levels compared to the BCNI group. These results indicate that the hFDM/PVA patch is effective in promoting angiogenesis, smooth muscle regeneration, and nitrergic nerve regeneration, which could contribute to improved erectile function in post-prostatectomy ED.

Vascular endothelium is the basic way for stem cells to treat erectile dysfunction: a bibliometric study

Vascular endothelial is considered to be a key factor in the pathogenesis of erectile dysfunction (ED). The purpose is to reveal the research trend of the field of ED and vascular endothelium. In addition, the goal is to discover the role and mechanism of vascular endothelium in ED. Bibliometrics and visualization methods based on CiteSpace were selected. We conducted the co-authorship analysis of countries, institutions and authors, co-occurrence analysis of keywords, and co-citation analysis of literature and authors through CiteSpace 6.1.R3. 1431 articles from Web of Science Core Collection (WOSCC) were included in the analysis from 1991 to 2022. We found some influential and cutting-edge nodes in each map, including countries, institutions, authors, articles, etc. Stem cell, therapy, oxidative stress, cavernous nerve injury, radical prostatectomy, fibrosis, erectile function, mesenchymal stem cell, and apoptosis may be hot keywords. In conclusion, the efficacy and mechanisms of stem cells and their derivatives in the treatment of diabetes (DM) ED and cavernous nerve injury (CNI) ED are the future research trends. Stem cells therapy for ED is a hot spot in this field, which side notes that stem cells may work mainly through improving endothelial function. Vascular endothelial cells and VEGF may repair nerve and cavernous smooth muscle directly or indirectly, and finally polish up erectile function.

Advances in physical diagnosis and treatment of male erectile dysfunction

Erectile dysfunction (ED) is the most common male sexual dysfunction by far and the prevalence is increasing year after year. As technology advances, a wide range of physical diagnosis tools and therapeutic approaches have been developed for ED. At present, typical diagnostic devices include erection basic parameter measuring instrument, erection hardness quantitative analysis system, hemodynamic testing equipment, nocturnal erection measuring instrument, nerve conduction testing equipment, etc. At present, the most commonly used treatment for ED is pharmacological therapy represented by phosphodiesterase five inhibitors (PDE5i). As a first-line drug in clinical, PDE5i has outstanding clinical effects, but there are still some problems that deserve the attention of researchers, such as cost issues and some side effects, like visual disturbances, indigestion, myalgia, and back pain, as well as some non-response rates. Some patients have to consider alternative treatments. Moreover, the efficacy in some angiogenic EDs (diabetes and cardiovascular disease) has not met expectations, so there is still a need to continuously develop new methods that can improve hemodynamics. While drug have now been shown to be effective in treating ED, they only control symptoms and do not restore function in most cases. The increasing prevalence of ED also makes us more motivated to find safer, more effective, and simpler treatments. The exploration of relevant mechanisms can also serve as a springboard for the development of more clinically meaningful physiotherapy approaches. Therefore, people are currently devoted to studying the effects of physical therapy and physical therapy combined with drug therapy on ED. We reviewed the diagnosis of ED and related physical therapy methods, and explored the pathogenesis of ED. In our opinion, these treatment methods could help many ED patients recover fully or partially from ED within the next few decades.

Management of male erectile dysfunction: From the past to the future

Erectile dysfunction is a common disease of the male reproductive system, which seriously affects the life quality of patients and their partners. At present, erectile dysfunction is considered as a social-psychological-physiological disease with complex etiology and various treatment methods. Oral PDE5I is the first-line treatment for erectile dysfunction with the advantages of high safety, good effect and non-invasiveness. But intracavernosal injection, hormonal replacement therapy, vacuum erection device, penile prosthesis implantation can also be alternative treatments for patients have organic erectile dysfunction or tolerance to PDE5I. With the rapid development of technologies, some new methods, such as low-intensity extracorporeal shock wave and stem cell injection therapy can even repair the organic damage of the corpora cavernosa. These are important directions for the treatment of male erectile dysfunction in the future. In this mini-review, we will introduce these therapies in detail.

Erectile dysfunction and exosome therapy

Erectile dysfunction (ED), as a common male disease, can seriously reduce the life quality of men and their partners. With the improvement of human living standards, ED is considered to be an important health issue that plagues men. However, it is difficult for existing therapeutic approaches to meet the needs of all patients, so it is necessary to develop novel treatment strategies. Exosomes, as a class of vesicles secreted by cells with bilayer membrane structure, are involved in various physiological and pathological processes in human body and considered to have great therapeutic potentials. This review summarizes the recent advances on exosome therapy with animal models of ED, and proposes the prospect of future research in order to provide a basis for clinical trials and clinical translation.

Extracellular vesicles from human urine-derived stem cells merged in hyaluronic acid ameliorate erectile dysfunction in type 2 diabetic rats by glans administration

BACKGROUND

The high prevalence of erectile dysfunction (ED) in patients with type 2 diabetes mellitus (DM2) is a challenging clinical problem. Researches on extracellular vesicles from urine-derived stem cells (USC-EVs) have shown that they have significant therapeutic effects in a variety of diseases by injection including ED. Hyaluronic acid (HA) is especially useful for delivering bioactive molecules. This study investigated the effects and related mechanisms of local administration of human USC-EVs combined with HA (USC-EVs-HA) on a rat model of DM2ED.

METHODS

UCSs were extracted from human urine samples and identified for preparation of the corresponding USC-EVs. The effects of high glucose and USC-EVs on human umbilical vein endothelial cells (HUVECs) were assessed in vitro using a CCK-8 assay to determine cell proliferation and pick the most appropriate concentration for subsequent experiments. Scratch and tube formation assays were performed to assess the function of HUVECs. Quantitative real-time polymerase chain reaction (PCR) was used to detect the expression of genes such as B-cell lymphoma-2 (Bcl-2), Bcl-2-associated X protein (BAX), and superoxide dismutase-2 (SOD2). HA, USC-EVs, and USC-EVs-HA were prepared at concentrations and then administered topically to DM2ED rats multiple times. Intracavernous pressure and mean arterial pressure were measured to assess erectile function in rats. Masson, Tunel, Immunohistochemistry, and Western blot analysis were performed to assess the fibrosis and endothelial function in corpus cavernosum, respectively.

RESULTS

Compared with the control group, the proliferation, migration ability, and tube-forming ability of HUVECs decreased in high glucose environment, while USC-EVs could optimize the function of HUVECs, reverse the expression of apoptotic genes, and enhance the antioxidant capacity. USC-EVs-HA showed improvement in ED compared to the HA and USC-EVs groups, and the 10-dose group was better than the 5-dose group. Histologically, the USC-EVs-HA group significantly improved apoptosis, angiogenesis, and smooth muscle regeneration in the corpus cavernosum compared to the HA group.

CONCLUSIONS

The topical application of USC-EVs-HA in the treatment of DM2ED rats has been proved effective. The potential mechanism might to promote the proliferation of endothelial cells and smooth muscle in the corpus cavernosum, which leads to the remodeling of erectile function. And multiple dosing at intervals may make the effect more pronounced.

Application of Stem Cell in Human Erectile Dysfunction - A Systematic Review

Introduction

Erectile dysfunction is a health problem that arises from various conditions and causes an impaired quality of life with a significant health burden. Regenerative and stem cell therapies are some of the potential treatments for erectile dysfunction. This study aimed to review the available information in the literature regarding the use of stem cells in the treatment of erectile dysfunction.

Methods

This study is a systematic review conducted based on the PubMed, Google Scholar, Cochrane, and DOAJ databases. Literature searching was conducted in English and included articles from 2000 to 2020.

Results

The result was a total of 318 articles. Following the elimination process, 9 articles remained in the final analysis. The analyzed studies included 164 patients with erectile dysfunction with various medical conditions. Several stem cell types have been used for treating erectile dysfunction, including mesenchymal stem cell, placental matrix-derived stem cell, mesenchymal stem cell-derived exosome, adipose-derived stem cell, bone marrow-derived mononuclear stem cell, and umbilical cord blood stem cell. Generally, stem cell therapy showed a good efficacy and safety profile, although not enough studies on the protocol, dosage, and mechanism of action.

Conclusion

Stem cell therapy has a good therapeutic potential in erectile dysfunction, the available data from the literature could be the base of usage of stem cells in the treatment of erectile dysfunction although need more research for broader usage.

The role of microRNAs in erectile dysfunction: From pathogenesis to therapeutic potential

Erectile dysfunction (ED) is a common male sexual dysfunction disease, and it was predicted that the number of ED patients worldwide will reach 322 million by 2025. However, the pathogenesis of ED is complex and the current treatment options are still limited, so it is urgent to explore new treatment strategies. Recent studies have shown that microRNAs (miRNAs) play an important role in ED, and these single-stranded non-coding small RNA molecules are involved in key pathophysiological processes in the occurrence and development of ED. Therefore, miRNAs have remarkable potential as therapeutic targets in ED. Here, this review introduces the physiological basis of erectile function and the pathophysiological changes in ED and summarizes the current knowledge on the expression, biological functions, and molecular mechanisms of miRNAs in ED, especially the potential of miRNA-targeted therapies to improve ED. This review will provide a comprehensive view of the role of miRNAs in the pathogenesis of ED and the potential value of miRNAs in the treatment of ED.

Human umbilical cord mesenchymal stem cells ameliorate erectile dysfunction in rats with diabetes mellitus through the attenuation of ferroptosis

Background

Erectile dysfunction (ED), as one of the most prevalent consequences in male diabetic patients, has a serious impact on men's physical and mental health, and the treatment effect of diabetic mellitus erectile dysfunction (DMED) is often worse. Therefore, the development of a novel therapeutic approach is urgent. As stem cells with high differentiation potential, human umbilical cord mesenchymal stem cells (HUCMSCs) have been widely used in the treatment of diseases in other systems, and are expected to be a promising strategy for the treatment of DMED. In this study, we investigated the role of HUCMSCs in managing erectile function in rat models of type 1 diabetes mellitus (T1DM) and type 2 diabetes mellitus (T2DM) and compared the effects of two different injection methods.

Methods

T1DM and T2DM ED rats were given labelled HUCMSCs by corpus cavernosum injection and tail vein injection, respectively. ICP and MAP were monitored simultaneously by electrical stimulation four weeks after injection to indicate the erectile function of rats. To track the development and colonisation capabilities of stem cells, we performed EdU assay with penile tissue. The histological changes of the penis were observed by hematoxylin–eosin staining, and Masson’s trichrome staining was conducted to evaluate the smooth muscle content and the degree of fibrosis in the rat penis. Then, we employed specific kits to measure the level of NO, cGMP, MDA, SOD and Fe in penis. Electron transmission microscopy was implemented to observe morphology of mitochondria. Besides, western blot and immunofluorescence staining were performed to demonstrate the expression of ferroptosis-related genes.

Results

We found that HUCMSCs improved erectile function in T1DM and T2DM ED rats, with no difference in efficacy between corpus cavernosum injection and tail vein injection. The EdU assay revealed that only a tiny percentage of HUCMSCs colonised the corpus cavernosum, while smooth muscle in the penis expanded and collagen decreased following HUCMSC injection. Moreover, the levels of oxidative stress in the penis of the rats given HUCMSCs were dramatically reduced, as was the tissue iron content. HUCMSCs normalised mitochondrial morphology within corpus cavernosum smooth muscle cells (CCSMCs), which were characteristically altered by high glucose. Furthermore, the expression of ferroptosis inhibitory genes SLC7A11 and GPX4 was obviously elevated in CCSMCs after stem cell management, but the abundances of ACSL4, LPCAT3 and ALOX15 showed the polar opposite tendency.

Conclusions

HUCMSCs can effectively and safely alleviate erectile dysfunction in T1DM and T2DM ED rats, while restoring erectile function by attenuating diabetes-induced ferroptosis in CCSMCs. Additionally, this study provides significant evidence for the development of HUCMSCs as a viable therapeutic strategy for DMED.

Supplementary Information

The online version contains supplementary material available at 10.1186/s13287-022-03147-w.

Rubus occidentalis and Ellagic Acid Affect the Contractility of Penile Corpus Cavernosum Smooth Muscle through the Nitric Oxide-Cyclic Guanosine Monophosphate and Cyclic Adenosine 3',5'-Monophosphate Signaling Pathway

The present study was designed to evaluate the relaxation effect of Rubus occidentalis (RO) and ellagic acid (EA) on rabbit penile corpus cavernosum smooth muscle (PCCSM). Rabbit PCCSM was treated with ROE or EA after preincubation with nitric oxide synthase (NOS), guanylate cyclase (GC), adenylyl cyclase (AC) or protein kinase A (PKA) blocker. Cyclic nucleotides in the perfusate were analyzed using radioimmunoassay (RIA). Subsequently, perfused PCCSMs were subjected to analysis to evaluate the expression level of endothelial nitric oxide synthase (eNOS) and neuronal nitric oxide synthase (nNOS). The interaction of ROE or EA with phosphodiesterase (PDE) 5 and PDE4 inhibitors, such as udenafil (UDE) and rolipram (ROL), were also evaluated. Both ROE and EA relaxed the PCCSM in a concentration-dependent manner. Coincubation of ROE or EA with NOS, GC, AC, or PKA blocker significantly decreased the ROE- and EA-induced relaxation. Pretreatment of ROE and EA significantly upregulated the cyclic guanosine monophosphate (cGMP), cyclic adenosine 3′,5′-monophosphate (cAMP), and eNOS levels in the perfused PCCSM. Furthermore, the treatment of ROE and EA markedly increased the UDE- and ROL-induced relaxation of the PCCSM. In conclusion, ROE and EA induced PCCSM relaxation by activating the nitric oxide (NO)-cGMp and cAMp signaling pathways and may have a synergistic action to improve erectile function.

Urine-Derived Stem Cells Versus Their Lysate in Ameliorating Erectile Dysfunction in a Rat Model of Type 2 Diabetes

Background: Diabetic erectile dysfunction (DED) is a significant consequence of diabetes mellitus, and it is a multifactorial phenomenon that has no definitive treatment until now. Many therapeutic options provide symptomatic improvement rather than addressing the underlying etiology or restoring normal function. Stem cell (SC) therapy represents a potential hope in DED management. It is well established that the regenerative effect of stem cells can be attained by their paracrine action and their ability to differentiate into many cell lineages, including endothelial and smooth muscle cells. Hence, we tried to compare the effects of transplantation of urine-derived stem cells (USCs) or their lysate (USC-L) into the corpora cavernosa (CCs) of rats with DED.

Materials and Methods: A total of 55 adult male Wistar rats were included in this study. USCs were obtained from ten healthy rats. Another ten rats did not subject to any intervention and served as a control (group I). Type 2 DM and DED were induced in the remaining 35 rats, but DED was tested and proved in only 24 rats, which were randomly divided into three groups (n = 8 in each). The DED group (group II) and either USCs (2 × 10⁶ cells) or their lysate (200 μl) were transplanted into the CCs of each rat in the other two groups (groups III and IV), respectively.

Results: Although the DED rats exhibited deterioration in all copulatory functions as compared to the control group, our histopathological, immunohistochemical, and morphometric results revealed that both USCs and USC-L have significantly restored the cavernous spaces, the ultrastructures of the endothelium that line the cavernous spaces, collagen/smooth muscle ratio, and the mean area percentage of α-SMA in the CCs as compared to DED rats. A respectable number of USCs was detected in the CCs of group III at the 4th week after transplantation, but this number significantly declined by the 8th week.

Conclusion: Both USCs and USC-L can repair the structure and ultrastructure of CCs and improve the copulatory functions in the DED rat model. However, USC-L could be better used in DED to guard against the strange behavior of USCs after transplantation and their decreased survivability with time.

International Continence Society (ICS) report on the terminology for sexual health in men with lower urinary tract (LUT) and pelvic floor (PF) dysfunction

INTRODUCTION

The terminology for sexual health in men with lower urinary tract (LUT) and pelvic floor (PF) dysfunction has not been defined and organized into a clinically based consensus terminology report. The aim of this terminology report is to provide a definitional document within this context that will assist clinical practice and research.

METHODS

This report combines the input of the members of sexual health in men with LUT and PF Dysfunction working group of the International Continence Society (ICS), assisted at intervals by external referees. Appropriate core clinical categories and a sub-classification were developed to give coding to definitions. An extensive process of 18 rounds of internal and external review was involved to exhaustively examine each definition, with decision-making by collective opinion (consensus). The Committee retained evidence-based definitions, identified gaps, and updated or discarded outdated definitions. Expert opinions were used when evidence was insufficient or absent.

RESULTS

A terminology report for sexual health in men with LUT and PF dysfunction, encompassing 198 (178 NEW) separate definitions, has been developed. It is clinically based with the most common diagnoses defined. Clarity and user-friendliness have been key aims to make it interpretable by practitioners and trainees in all the different speciality groups involved. Conservative and surgical managements are major additions and appropriate figures have been included to supplement and clarify the text. Emerging concepts and measurements, in use in the literature and offering further research potential, but requiring further validation, have been included as an appendix. Interval (5-10 years) review is anticipated to keep the document updated.

CONCLUSION

A consensus-based terminology report for sexual health in men with LUT and PF dysfunction has been produced to aid clinical practice and research. The definitions that have been adopted are those that are most strongly supported by the literature at this time or are considered clinical principles or consensus of experts' opinions.

Effects of Stem Cell Therapy on Diabetic Mellitus Erectile Dysfunction: A Systematic Review and Meta-analysis

BACKGROUND

Stem cell is considered a potential therapy for treating erectile dysfunction (ED), including diabetic mellitus erectile dysfunction (DMED), which was investigated in some preclinical studies. Several trials introduced stem cell into clinical practice, but divergences emerged.

AIM

To further investigate the therapeutic effects of stem cell on DMED in preclinical studies and investigate some possible factors that influence curative effects.

METHODS

The literature research was conducted in Web of Science and PubMed to retrieve studies utilizing stem cell to treat DMED. Revman 5.3 was used to perform subgroup analysis of intracavernosal pressure/mean artery pressure (ICP/MAP) and structural changes. Publication bias was assessed with Egger's test, funnel plot, and sensitivity analysis by Stata 15.0.

OUTCOMES

The ICP/MAP and structural changes before and after stem cell treatment.

RESULTS

Of 2,115 studies retrieved, 23 studies are eligible. Plus 10 studies from a meta-analysis published in 2016, 33 studies were enrolled. Pooled analysis showed that stem cell ameliorates damaged ICP/MAP (WMD 0.26; 95% CI 0.23-0.29; P < .001) and structural changes induced by diabetes. Subgroup analysis indicated that adipose-derived mesenchymal stem cell (ADSC) may have better efficacy than bone marrow-derived mesenchymal stem cell (BMSC) (χ2= 4.21, P = .04; ADSC WMD 0.28, 95% CI [0.24-0.32] vs BMSC WMD 0.22 95% CI [0.17-0.26]). Transplantation type, diabetes type, and cell number make no difference to curative effects. Gene modification and therapy combination proved promising in improving the therapeutic effects of stem cell.

CLINICAL TRANSLATION

The evidence reminded that ADSC may be prior to BMSC in clinical trials and autotransplantation is probably not compulsory in the clinical practice of stem cell.

STRENGTHS AND LIMITATIONS

The study number and sample size are large enough. However, high degree of heterogeneity remains after subgroup analysis.

CONCLUSION

This meta-analysis suggests the efficacy of stem cell therapy for DMED and the possible superiority of ADSC over BMSC in erection restoration and structure renovation.

Canadian Urological Association guideline: Erectile dysfunction

Erectile dysfunction (ED) impacts the wellness and quality of life of millions of Canadians. An evaluation focused on the identification of reversible and irreversible underlying factors is recommended for patients presenting with ED. Through a shared decision-making model framework, the goal of ED treatment is to improve functional outcomes and enhance sexual satisfaction while minimizing adverse effects associated with treatment. Given that ED is assessed and treated by multiple different types of health practitioners, the purpose of this guideline is to provide the best available evidence to facilitate care delivery through a Canadian lens. After a narrative review of ED assessment and treatment for general readership, five key clinical questions relating to priority areas of ED are assessed using the GRADE and evidence-to-decision-making frameworks.

Effects of Cells Self-aggregation in the Treatment of Neurogenic Erectile Dysfunction With Traditional Single Cell Suspension of Adipose-derived Stem Cells

OBJECTIVE

To clarify the effects of cellular self-aggregation of adipose-derived stem cells (ADSCs) on erectile function (EF).

METHODS

A model of neurogenic erectile dysfunction was performed using bilateral cavernous nerve crush injury in rats. ADSCs suspensions (1 × 10⁶/0.2 ml), were administered via intracavernous injection (ICI) after being allowed to shelve for 0 minute (ICI 0) or 60 minutes (ICI 60) in vitro, as well as cell aggregates isolated from ICI 60 (ICI A). The caudal vein injection group (CVI 60) was used to evaluate whether cell self-aggregation was beneficial to EF when introduced into the peripheral circulation. One day after the transplantation, the distribution of cells was observed. EF and histopathological changes were evaluated after 4 weeks.

RESULTS

Approximately 85% of ADSCs self-aggregated into cell clusters at 60 minutes. The ICI 60 had more significant improvements in EF and more visualized ADSCs retained in the corpus cavernosum (CC) than ICI 0 and CVI 60 (P <.05), but no significant difference between ICI 60 and ICI A. In the CVI 60 group, the cell clusters formed by self-aggregation could hardly reach the CC and were mostly found in lung tissue. Immunofluorescence staining showed increased the content of expressing biomarkers of smooth muscle, nerve within the CC tissue in the ICI groups when compared to the CVI group.

CONCLUSION

ADSCs self-aggregation before ICI may be an influential factor in the treatment of neurogenic erectile dysfunction. Its potential mechanism may be through improving cell retention in the CC.

The use of combination regenerative therapies for erectile dysfunction: rationale and current status

Erectile Dysfunction (ED) is defined as the inability to achieve and maintain an erection sufficient for sexual intercourse. Available treatments for ED provide only symptomatic relief, which is for the most part temporary. Regenerative therapies such as Low Intensity Shockwave, Platelet-Rich Plasma, and Stem Cell therapy can potentially provide a "cure" for ED by reversing the underlying pathology of ED rather than just treating the symptoms. Low Intensity Shockwave therapy is the most evidence based at this point and is thought to act by improving penile blood flow, repairing previous nerve damage, and activating stem cells. Stem Cell therapy takes advantage of the self-replicative potential of stem cells to create new corporal tissue, but also to recruit host cells and angiogenic factors to stimulate endogenous repair. Platelet-Rich Plasma therapy uses concentrated growth factors that already exist within the bloodstream to repair damaged nerves and increase penile blood flow. The use of combination restorative therapy may provide an additive or synergistic benefit greater than any one therapy alone because of its overlapping mechanisms of action on the penis but is a topic that remains to be studied.

A novel flavonoid derivative of icariside II improves erectile dysfunction in a rat model of cavernous nerve injury

BACKGROUND

Icariside II (ICA II), an active flavonoid monomer, has been proven to restore post-prostatectomy erectile dysfunction in rats; however, the high cost of extraction from natural plants limits the application of ICA II.

OBJECTIVE

To investigate the therapeutic effect and possible mechanism of action of YS-10, a new flavonoid compound, which was designed and synthesized based on the structure of ICA II in a rat model in of cavernous nerve injury.

MATERIALS/METHODS

Eight of 32 adult male Sprague-Dawley rats were selected as the normal control (NC) group and received vehicle treatment. The remaining rats were subjected to bilateral cavernous nerve injury (BCNI) and randomized into three groups: BCNI group, BCNI + ICA II group (2.5 mg/kg/day), and BCNI + YS-10 group (2.5 mg/kg/day). The total procedure lasted for 21 days, followed by a washout period of 3 days. All animals were evaluated for erectile function, and tissues were harvested for histopathological analyses.

RESULTS

It was observed that in YS-10 group, the ratio of intracavernous pressure (ICP) to mean arterial pressure (MAP) and the area under the ICP/MAP curve were effectively enhanced. The maximum ICP/MAP increased by 30% in the YS-10 group (0.86 ± 0.085) compared with the BCNI group (0.66 ± 0.058), which is close to 82% of the NC group (1.05 ± 0.033). Histopathological changes demonstrated significant reduction of smooth muscle atrophy, collagen deposition, and endothelial and neural dysfunction after YS-10 treatment, which have no statistical differences compared with ICA II group. Additionally, high-protein expression levels of β-Catenin and cyclin D1 were observed in the treatment groups.

CONCLUSION

YS-10, a novel synthesized flavonoid compound, could effectively improve erectile dysfunction in rats after BCNI by alleviating pathological impairments; this effect may associate with the upregulation of β-Catenin and cyclin D1 in Wnt signaling pathway.

Restorative Therapies for Erectile Dysfunction: Position Statement From the Sexual Medicine Society of North America (SMSNA)

INTRODUCTION

Current non-invasive treatments for erectile dysfunction (ED) include oral medications, intracavernosal injections, and vacuum-assisted devices. Though these therapies work well for many, a subset of patients have contraindications or are unsatisfied with these options. Restorative therapies for ED are a new frontier of treatments focused on regenerating diseased tissue and providing a potential "cure" for ED.

AIM

The aim of this position statement is to examine existing clinical trial data for restorative therapies and identify elements that require further research before widespread adoption.

METHODS

A literature review was performed to identify all clinical trials performed with regenerative therapy for ED. This includes treatments such as stem cell therapy (SCT), platelet rich plasma (PRP), and restorative related technologies like low-intensity shockwave therapy (LiSWT).

MAIN OUTCOME MEASURES

Most clinical trials in restorative therapies were assessed for safety, feasibility, or efficacy. This included recording adverse events, changes in sexual function and erectile function questionnaires, and diagnostics measures.

RESULTS

To date there is an absence of robust clinical data supporting the efficacy of restorative therapies regarding ED, though technologies such as LiSWT have established relative safety.

CONCLUSIONS

Restorative therapies are a promising technology that represents a new frontier of treatment geared towards reversing disease pathology rather than just treating symptoms. However, current published clinical studies are limited. Future work needs to be adequately powered, multi-center, randomized, sham/placebo-controlled trials in well-characterized patient populations to ensure safety and demonstrate efficacy. Until these studies are done, restorative therapies should be reserved for clinical trials and not offered in routine clinical practice. Liu JL, Chu KY, Gabrielson AT, et al. Restorative Therapies for Erectile Dysfunction: Position Statement From the Sexual Medicine Society of North America (SMSNA). J Sex Med 2021;9:100343.

Identification of key genes in type 2 diabetes-induced erectile dysfunction rats with stem cell therapy through high-throughput sequencing and bioinformatic analysis

Diabetes mellitus erectile dysfunction (DMED) is a frequent complication of diabetes. Mesenchymal stem cell (MSC) therapy was demonstrated to improve erectile function in DMED. However, the pathogenesis of DMED and the mechanism by which MSCs function are still unclear. We established a rat model of DMED and gave MSC therapy through intracavernous injection. After transcriptome sequencing of rats' penile tissue, we identified a total of 1,097 overlapped differentially expressed genes (DEGs) of the normal control group, DMED group, and MSC-treated group, containing 189 upregulated genes and 908 downregulated genes. The enriched functions of upregulated DEGs included extracellular matrix organisation (GO:0030198), extracellular structure organisation (GO:0043062), and wound healing (GO:0042060), PPAR signalling pathway (rno03320), arachidonic acid metabolism (rno00590) and retinol metabolism (rno00830). The enriched functions of downregulated DEGs included peptidase activity (GO:0052547), hair follicle development (GO:0001942), intermediate filament-based process (GO:0045103), nitrogen metabolism (rno00910), aldosterone-regulated sodium reabsorption (rno04960) and retinol metabolism (rno00830). We constructed a PPI network with 547 nodes and 2,365 edges and identified 15 hub genes with high connectivity degree. In summary, 15 hub genes with potential roles in the development of ED were identified. Further functional research would be required to elucidate the molecular mechanism underlying misregulated genes.

Exosomes derived from miR-301a-3p-overexpressing adipose-derived mesenchymal stem cells reverse hypoxia-induced erectile dysfunction in rat models

Background

Erectile dysfunction (ED) has often been observed in patients with obstructive sleep apnea (OSA). Research on adipose-derived mesenchymal stem cell (ADSC)-derived exosomes has shown that they have significant therapeutic effects in many diseases including ED.

Methods

In this study, ED was induced in Sprague Dawley (SD) rats using chronic intermittent hypoxia (CIH) exposure. CIH-mediated influences were then measured in the corpus cavernous smooth muscle cells (CCSMCs).

Results

Our data showed that miR-301a-3p-enriched exosome treatment significantly recovered erectile function in rats and CCSMCs by promoting autophagy and inhibiting apoptosis. The treatment also significantly recovered the level of alpha smooth muscle actin (α-SMA) in rats and CCSMCs. Bioinformatics predicted that phosphatase and tensin homolog (PTEN) and Toll-like receptor 4 (TLR4) might be targets of miR-301a-3p.

Conclusions

Our results indicate that PTEN-overexpression vectors or TLR4-overexpression vectors reverse the therapeutic effects achieved by miR-301a-3p in CCSMCs indicating that PTEN/hypoxia-inducible factor-1 alpha (HIF-1α) and TLR4 signaling pathways play key roles in the progression of ED. The findings in this study suggest that miR-301a-3p should be considered a new therapeutic target for treating ED associated with OSA.

Supplementary Information

The online version contains supplementary material available at 10.1186/s13287-021-02161-8.

The Role of Mesenchymal Stromal Cells-Derived Small Extracellular Vesicles in Diabetes and Its Chronic Complications

Mesenchymal stromal cells (MSCs) are applied in regenerative medicine of several tissues and organs nowadays by virtue of their self-renewal capabilities, multiple differentiation capacity, potent immunomodulatory properties, and their ability to be favourably cultured and manipulated. With the continuous development of "cell-free therapy" research, MSC-derived small extracellular vesicles (MSC-sEVs) have increasingly become a research hotspot in the treatment of various diseases. Small extracellular vesicles (SEVs) are membrane vesicles with diameters of 30 to 150 nm that mediate signal transduction between adjacent or distal cells or organs by delivering non-coding RNA, protein, and DNA. The contents and effects of sEVs vary depending on the properties of the originating cell. In recent years, MSC-sEVs have been found to play an important role in the occurrence and development of diabetes mellitus as a new way of communication between cells. Diabetes mellitus is a common metabolic disease in clinic. Its complications of the heart, brain, kidney, eyes, and peripheral nerves are a serious threat to human health and has been a hot issue for clinicians. MSC-sEVs could be applied to repair or prevent damage from the complications of diabetes mellitus through anti-inflammatory effects, reduction of endoplasmic reticulum-related protein stress, polarization of M2 macrophages, and increasing autophagy. Therefore, we highly recommend that MSC-sEVs-based therapies to treat diabetes mellitus and its chronic complication be further explored. The analysis of the role and molecular mechanisms of MSC-sEVs in diabetes and its related complications will provide new idea and insights for the prevention and treatment of diabetes.

Thinking About Pathomechanisms and Current Treatment of Erectile Dysfunction-"The Stanley Beamish Problem." Review, Recommendations, and Proposals

INTRODUCTION

Up to 50% of all men over 50 years of age suffer from erectile dysfunction. Since the late 1990s erectile dysfunction has been treated mostly with phosphodiesterase 5 inhibitors (PDE5I). Over the past 20 years, numerous scientific findings on the development of erectile dysfunction have been collected, which have so far received little attention in the treatment of erectile dysfunction.

OBJECTIVES

The objectives of this study were to review the existing medical literature on erectile dysfunction regarding physiology, pathophysiology, and especially therapeutic options beyond treatment with PDE5I and to enable a more effective and especially sustainable treatment for erectile dysfunction.

METHODS

A literature review was performed by using PubMed from 1985 to 2020 regarding the physiology, pathophysiology, and treatment of erectile dysfunction.

RESULTS

Since the end of the 1990s an enormous amount of knowledge has been gained about the physiology/pathophysiology of erection/erectile dysfunction. Based on these findings, numerous physical, drug, and holistic therapeutic options (beyond the application of PDE5I) have been developed for the treatment of erectile dysfunction. However, these are still relatively rarely used in the therapeutic concept of erectile dysfunction today.

CONCLUSION

Based on scientific findings of the last 20 years, there are numerous therapeutic approaches, including lifestyle modification, specific pelvic floor exercises, shock wave treatment, and the application of different supplements. The long-term treatment of erectile dysfunction should now go beyond the purely symptomatic use of PDE5I. W-D Beecken, M Kersting, W Kunert, et al. Thinking About Pathomechanisms and Current Treatment of Erectile Dysfunction-"The Stanley Beamish Problem." Review, Recommendations, and Proposals. Sex Med Rev 2021;9:445-463.

Mesenchymal stem cells-derived exosomal microRNA-21-5p downregulates PDCD4 and ameliorates erectile dysfunction in a rat model of diabetes mellitus

Erectile dysfunction (ED) is a common comorbidity in males with diabetes mellitus (DM), whose pathogenesis might be induced by dysregulation of corpus cavernosum smooth muscle cells (CCSMCs). Gene Expression Omnibus repository-based analysis identified the differentially expressed PDCD4 in DM rats. PDCD4 has also been determined as a putative gene under the regulatory control of microRNA-21-5p (miR-21-5p). This study aimed to further determine the functional role of miR-21-5p in CCSMCs in a rat model of diabetes mellitus-induced erectile dysfunction (DMED). CCSMCs were isolated from penile cavernous tissue and cultured in high glucose (HG) medium. The expression of miR-21-5p and/or PDCD4 was altered in CCSMCs, as directly or indirectly measured by CCK-8 assay, flow cytometry, and TUNEL assays. Furthermore, exosomes were isolated from mesenchymal stem cells (MSCs) transfected with miR-21-5p mimic or miR-21-5p inhibitor and co-cultured with CCSMCs. DMED rats were injected with lentivirus carrying PDCD4/siRNA-PDCD4 plasmids, or exosomes from MSCs containing miR-21-5p-agomir to explore their roles in vivo. The experimental data validated that PDCD4 was upregulated in cavernous tissue of DMED rats. miR-21-5p targeted and inhibited PDCD4. miR-21-5p was enriched in MSC-exosomes. Moreover, PDCD4 downregulation, miR-21-5p elevation or MSC-derived exosomal miR-21-5p reduced apoptosis and enhanced proliferation of CCSMCs cultured in HG medium. PDCD4 silencing or miR-21-5p-containing MSC-exosomes improved erectile function and smooth muscle density in DMED rats. Collectively, our findings suggested that MSC-derived exosomal miR-21-5p suppressed PDCD4 expression and ED in rats with DM.

Probucol enhances the therapeutic efficiency of mesenchymal stem cells in the treatment of erectile dysfunction in diabetic rats by prolonging their survival time via Nrf2 pathway

BACKGROUND

Intracavernous injection of mesenchymal stem cells (MSCs) is a promising method for diabetic mellitus-induced erectile dysfunction (DMED), but short survival time of MSCs in cavernous is a fatal defect for therapy. This study investigated therapeutic efficiency and potential mechanism of probucol combined with MSCs.

METHODS

In vivo study, a total of forty-eight 10-week-old male Sprague-Dawley (SD) rats were used. Twelve rats received intraperitoneal injection of PBS as the sham group; the rest received intraperitoneal injection of 60 mg/kg streptozotocin to establish DM models. DM rats were randomly divided into three groups: received intracavernosal (IC) injection of either PBS (DM group), MSCs (M group), or administrated probucol after intracavernosal injection of MSCs (P + M group). Erectile function was assessed by electrical stimulation of the cavernous nerves with real-time intracavernous pressure measurement. After euthanasia, penile tissue was investigated for histologic examination and Western blotting. In in vitro experiment, H2O2 was used to create oxidative stress environment to detect changes in cell viability. CCK8 was used to measure cell viability of MSCs treated with or without probucol. Intracellular ROS changes were detected by flow cytometry. Autophagy and apoptosis were detected by Western blotting and confocal microscopy.

RESULTS

Recovery of erectile function was observed in the P + M group. The combination therapy decreased fibrosis and increased endothelial function compared with MSC therapy alone. Western blotting results confirmed the increased expression of Nrf2 and HO-1 in cavernous body. H2O2 induced high oxidative stress and reduced cell viability in vitro, which was gradually reversed with increased concentration of probucol. H2O2 reduced Nrf2 expression, which was reversed by probucol's intervention. Furthermore, the expression of Bax, Caspase3, and Cleaved-Caspase3 decreased, and the expression of Bcl-2 increased in a dose-dependent manner because of probucol's intervention. In addition, Beclin1 and LC3II both increased in a dose-dependent manner. Meanwhile, the expression of P62 decreased. In the study of autophagy flux, we found probucol did not block it.

CONCLUSION

Probucol enhanced therapeutic efficiency of MSCs in DMED by prolonging their survival time, which mediated through improving the transplanted microenvironment of MSCs, increasing self-antioxidant ability of MSCs, strengthening protective autophagy, and inhibiting apoptosis of MSCs via Nrf2 pathway. Schematic model showing combined probucol and MSCs to improve DMED. Probucol increases self-antioxidant ability of MSCs, strengthening protective autophagy and inhibiting apoptosis via Nrf2/HO-1 and Nrf2/autophagy pathways.

Revisiting the Regenerative Therapeutic Advances Towards Erectile Dysfunction

Erectile dysfunction (ED) is an inability to attain or maintain adequate penile erection for successful vaginal intercourse, leading to sexual and relationship dissatisfaction. To combat ED, various surgical and non-surgical approaches have been developed in the past to restore erectile functions. These therapeutic interventions exhibit significant impact in providing relief to patients; however, due to their associated adverse effects and lack of long-term efficacy, newer modalities such as regenerative therapeutics have gained attention due to their safe and prolonged efficacy. Stem cells and platelet-derived biomaterials contained in platelet-rich plasma (PRP) are thriving as some of the major therapeutic regenerative agents. In recent years, various preclinical and clinical studies have evaluated the individual, as well as combined of stem cells and PRP to restore erectile function. Being rich in growth factors, chemokines, and angiogenic factors, both stem cells and PRP play a crucial role in regenerating nerve cells, myelination of axons, homing and migration of progenitor cells, and anti-fibrosis and anti-apoptosis of damaged cavernous nerve in corporal tissues. Further, platelet-derived biomaterials have been proven to be a biological supplement for enhancing the proliferative and differentiation potential of stem cells towards neurogenic fate. Therefore, this article comprehensively analyzes the progresses of these regenerative therapies for ED.

Stem Cell/Oxygen-Releasing Microparticle Enhances Erectile Function in a Cavernous Nerve Injury Model

Erectile dysfunction caused by damage to the cavernous nerve is a common complication of radical prostatectomy for patients with localized prostate cancer. Various studies have investigated repair of damaged tissue and prevention of fibrosis in the corpus cavernosum using stem cell therapy. However, stem cell therapy has limitations, including insufficient nutrient and oxygen supply to transplanted stem cells. This study investigated whether stem cell/oxygen-releasing hollow microparticles (HPs) had therapeutic effect on erectile dysfunction in a rat model of bilateral cavernous nerve injury (BCNI). Therapeutic effects were observed in the BCNI model at 1, 2, and 4 weeks postcavernous nerve injury. Erectile function further improved after treatment with stem cell/oxygen-releasing HP system compared with treatment with only stem cells at 4 weeks. Stem cell/oxygen-releasing HP system increased cyclic guanosine monophosphate (cGMP) level and neuronal nitric oxide synthase (nNOS), endothelial nitric oxide synthase (eNOS), α-smooth muscle actin (α-SMA), and muscarinic acetylcholine receptor 3 (M3) expression while decreasing fibrosis and apoptosis in the corpus cavernosum. Our results clearly show that stem cell survival increases around transplanted stem cell/oxygen-releasing hybrid system site. Taken together, an oxygen-releasing HP system supported prolonged stem cell survival, sustaining the paracrine effect of the stem cells, and consequently enhancing erectile function. These findings show promise with regard to prolonged stem cell survival in stem cell applications for various diseases and types of tissue damage. Impact statement In this study, we used an oxygen-releasing hollow microparticles (HPs) system with stem cells to attempt to overcome certain limitations of stem cell therapy, including insufficient nutrient and oxygen supplies for transplanted stem cells. Our results demonstrated that a stem cell/oxygen-releasing HP hybrid system could further improve erectile function, cyclic guanosine monophosphate (cGMP) level, and NOS level in a bilateral cavernous nerve injury rat model through prolonged stem cell survival. Our data suggest that a stem cell/oxygen-releasing HP system is a promising clinical treatment option for postprostatectomy erectile dysfunction. Furthermore, this system may be relevant in different disease therapies and regenerative medicine.

The good, bad, and the ugly of regenerative therapies for erectile dysfunction

Erectile dysfunction (ED) is a common condition which reduces quality of life of both patients and their partners, and is a significant health care expense every year. Although phosphodiesterase type-5 inhibitors are the current first-line treatment for men with ED, they are limited by their on-demand dosing, intolerance, and variable efficacy in complex patient populations such as men with multiple medical comorbidities or ED after pelvic surgery. Regenerative medicine has been introduced and investigated in andrology as an encouraging strategy to restore diseased erectile tissue structure and function. Novel regenerative therapies for ED are controversial but are perceived to offer a durable and safe tissue restorative approach to act as a long-term solution to this cumbersome disease process. Here, we review platelet-rich plasma, amniotic fluid membranes, low-intensity extracorporeal shockwave therapy, and stem cell therapy as regenerative strategies to treat ED. Most of these approaches have preclinical and occasionally clinical data to support their ongoing investigation; however, none of these treatments are currently supported for use in ED patients outside of clinical trials.

Treatment of the bone marrow stromal stem cell supernatant by nasal administration-a new approach to EAE therapy

Introduction

Multiple sclerosis (MS) is one of the most common autoimmune diseases of the central nervous system (CNS). CNS has its own unique structural and functional features, while the lack of precision regulatory element with high specificity as therapeutic targets makes the development of disease treatment in the bottleneck. Recently, the immunomodulation and neuroprotection capabilities of bone marrow stromal stem cells (BMSCs) were shown in experimental autoimmune encephalomyelitis (EAE). However, the administration route and the safety evaluation limit the application of BMSC. In this study, we investigated the therapeutic effect of BMSC supernatant by nasal administration.

Methods

In the basis of the establishment of the EAE model, the BMSC supernatant were treated by nasal administration. The clinical score and weight were used to determine the therapeutic effect. The demyelination of the spinal cord was detected by LFB staining. ELISA was used to detect the expression of inflammatory factors in serum of peripheral blood. Flow cytometry was performed to detect pro-inflammatory cells in the spleen and draining lymph nodes.

Results

BMSC supernatant by nasal administration can alleviate B cell-mediated clinical symptoms of EAE, decrease the degree of demyelination, and reduce the inflammatory cells infiltrated into the central nervous system; lessen the antibody titer in peripheral bloods; and significantly lower the expression of inflammatory factors. As a new, non-invasive treatment, there are no differences in the therapeutic effects between BMSC supernatant treated by nasal route and the conventional applications, i.e. intraperitoneal or intravenous injection.

Conclusions

BMSC supernatant administered via the nasal cavity provide new sights and new ways for the EAE therapy.

Mesenchymal Stem Cells Treatment for Erectile Dysfunction in Diabetic Rats

INTRODUCTION

Aging men with diabetes mellitus are more easily suffering from erectile dysfunction (ED), which was poor to respond to drugs. Mesenchymal stem cell treatment (MSCT) offers us an alternative approach that might reverse diabetes mellitus erectile dysfunction (DMED).

AIM

The aim of this study was to review the current studies investigating mesenchymal stem cell approach in diabetic rat models of ED for future research.

METHODS

A medical literature search was performed in PubMed by using the keywords including erectile dysfunction, mesenchymal stem cells, diabetes mellitus, and rat model.

MAIN OUTCOME MEASURE

Representative studies on DMED rats treated by MSCT were reviewed.

RESULTS

Streptozocin-induced type 1 diabetes mellitus rats were used in most studies because of cost and convenience. With the development of stem cell treatment for DMED research, many kinds of stem cells were used in animal experiment, such as bone marrow-derived mesenchymal stem cells, adipose-derived stem cells, human umbilical cord blood mononuclear cells, muscle-derived stem cells, urine-derived stem cells, neural crest stem cells, and endothelial progenitor cells. Although diverse stem cells were applied for DMED treatment, the mechanism behind these approaches was identical, including improving vascular injury, recovering smooth muscle, restoring neuronal cells, inhibiting the generation of inflammatory cytokines, homing mesenchymal stem cells, and decreasing apoptosis in corpus cavernosum. Meanwhile, combination therapies, including MSCT with drug, herb, and low-energy extracorporeal shockwave treatment showed satisfactory results for ED.

CONCLUSION

It has been proved that MSCT is an effective and safe treatment for the DMED rats. What's more, MSCT might be a potential and promising approach for patients with DMED as a minimally invasive treatment. Combination of MSCT with various methods was proved to be a more efficient treatment and dependable option to make up for deficiencies of MSCT. Kim SW, Zhu GQ, Bae WJ. Mesenchymal Stem Cells Treatment for Erectile Dysfunction in Diabetic Rats. Sex Med Rev 2020;8:114-121.

Adipose Tissue-Derived Stem Cell Therapy for Cavernous Nerve Injury-Induced Erectile Dysfunction in the Rat Model: A Systematic Review and Meta-Analysis Using Methodological Quality Assessment

Background and Objectives

Few studies were evaluated the effect of blindness on outcome in animal models, though a potential effect of blinding has been reported in clinical trials. We evaluated the effects of adipose tissue-derived stem cells (ADSCs) on cavernous nerve injury (CNI)-induced erectile dysfunction (ED) in the rat and examined how proper blinding of the outcome assessor affected treatment effect.

Methods and Results

We searched in Pubmed, EMBASE, Cochrane and Web of Science databases from inception to January 2019. We included CNI animal model, randomized controlled experiments, and ADSC intervention. Erectile function and structural changes were assessed by intracavernous pressure and mean arterial pressure (ICP/MAP) ratios, neuronal nitric oxide synthase (nNOS) levels, cavernous smooth muscle and collagen (CSM/collagen) ratios, and cyclic guanosine monophosphate (cGMP).

Results

Nineteen studies were included in the final meta-analysis. The ICP/MAP ratio of the ADSC treatment group increased compared to the control group (SMD=1.33, 95%CI: 1.11~1.56, I²=72%). The nNOS level (SMD=2.29, 95%CI: 1.74~2.84, I²=75%), CSM/collagen (SMD=2.57, 95%CI: 1.62~3.52; I²=85%), and cGMP (SMD=2.96, 95%CI: 1.82~4.10, I²=62%) were also increased in the ADSC treatment group. Preplanned subgroup analysis was conducted to explore the source of heterogeneity. Five studies with blinded outcome assessment were significantly less effective than the unblinded studies (SMD=1.33, 95%CI: 0.86~1.80; SMD=1.81, 95%CI: 1.17~2.46, respectively).

Conclusions

ADSCs might be effective in improving erectile function and structural change in CNI-induced ED. However, non-blinded outcome assessors might cause detection bias and overestimate treatment efficacy. Therefore, the ADSC efficacy must be further evaluated with a rigorous study design to avoid bias.

The Effect of Bupivacaine on the Efficacy of Antibiotic Coating on Penile Implants in Preventing Infection

Background

In an effort to reduce dependence on opioids following inflatable penile prosthesis placement, intra-operative soaking of the implant in Bupivacaine (BUP) has been proposed as part of a multimodal approach to pain control. However, no study has shown if the addition of BUP affects the antimicrobial properties of InhibiZone on AMS700 (Boston Scientific, Marlborough, MA) and/or of antibiotic soaked Titan Coloplast (Coloplast Corporation, Minneapolis, MN).

Aim

To determine if BUP alters the zone of inhibition (ZOI) against Staphylococcus epidermidis (S epidermidis) and Escherichia coli (E coli), common gram-positive and gram-negative bacterial causes of infection, respectively, created by InhibiZone coated AMS and/or by antibiotic-soaked Coloplast implant.

Methods

S epidermidis and E coli were spread on agar plates. After a 30-minute incubation, four AMS with InhibiZone strips treated with sterile saline or BUP (1.25 mg/mL) were placed on a plate. 4 Coloplast strips were dipped in varying routinely used concentrations of Rifampin (0–10 mg/mL) plus Gentamicin (0–1 mg/mL; rifampin and gentamicin (R+G)) solution with or without BUP. The ZOI for AMS with InhibiZone and Coloplast dipped in antibiotic solution was measured using ImageJ software. Normalized ZOI was calculated as (ZOI area/plate area) × 100. Unpaired t-test compared the mean ± SD ZOI between BUP and no BUP groups (n = 4/group).

Outcomes

The primary outcome of the study was the ZOI against E coli and S epidermidis at 24 and 48 hours.

Results

Growth of both S epidermidis and E coli at 24 and 48 hours of incubation was inhibited in both implants and the addition of BUP did not alter the ZOI. Coloplast strips dipped in R+G produced a ZOI in a dose-dependent manner. Interestingly, the ZOI against S epidermidis compared to that of E coli was much wider for both implants.

Clinical Implications

This suggests that the use of BUP does not affect the protective effects of antibiotic dips and can potentially be used during penile prosthesis surgery pending clinical trials.

Strengths and Limitations

This is the first study to evaluate the effect of BUP on anti-bacterial dips. As with all in vitro analysis, further research must be done to see if these findings hold true in the clinical setting.

Conclusions

The addition of BUP does not impede the in vitro antibacterial activity of InhibiZone-coated AMS or R+G-soaked Coloplast. Whether these in vitro findings translate to surgical outcomes needs to be evaluated in future preclinical trials.

Lokeshwar SD, Horodyski L, Lahorewala SS, et al. The Effect of Bupivacaine on the Efficacy of Antibiotic Coating on Penile Implants in Preventing Infection. J Sex Med 2019;7:337−344.