Long‐term therapeutic effect of cell therapy on improvement in erectile function in a rat model with pelvic neurovascular injury

Prevention of post-operative adhesions: Model development and pilot outcomes of human placental stem cell-based interventions

BACKGROUND

Abdominal adhesions are the most common surgical complication and without reliable prophylactics. This study presents a novel rat model for abdominal adhesions and reports pilot results of human placental stem cell (hPSC)-based therapies.

METHODS

Forty-four (n = 44) male Sprague-Dawley rats (250-350 g) were used in the experiment. Of these, thirty-eight (n = 38) were included in a preliminary data set to determine a minimum treatment effect. Adhesions were created in a reproducible model to the abdominal wall and between organs. Experimental groups included the control group (Model No Treatment, MNT), Plasmalyte A (Media Alone, MA, 10 mL), hPSC (5 × 106 cells/10 mL Plasmalyte A), hPSC-CM (hPSC secretome, conditioned media) in 10 mL Plasmalyte A, Seprafilm™ (Baxter, Deerfield, IL), and sham animals (laparotomy only). Treatments were inserted intraperitoneally (IP) and the study period was 14 days post-operation. Results are reported as the difference between means of an index statistic (AIS, Animal Index Score) and compared by ANOVA with pairwise comparison.

RESULTS

The overall mean AIS was 23 (SD 6.16) for the MNT group with an average of 75% of ischemic buttons involved in abdominal adhesions. Treatment groups MA (mean overall AIS 17.33 SD 6.4), hPSC (mean overall AIS 13.86 SD 5.01), hPSC-CM (mean overall AIS 13.13 SD 6.15), and Seprafilm (mean overall AIS 13.43 SD 9.11) generated effect sizes of 5.67, 9.14, 9.87, and 9.57 decrease in mean overall AIS, respectively, versus the MNT.

DISCUSSION

The presented rat model and scoring system represent the clinical adhesion disease process. hPSC-based interventions significantly reduce abdominal adhesions in this pilot dataset.

Body fluid-derived stem cells - an untapped stem cell source in genitourinary regeneration

Somatic stem cells have been obtained from solid organs and tissues, including the bone marrow, placenta, corneal stroma, periosteum, adipose tissue, dental pulp and skeletal muscle. These solid tissue-derived stem cells are often used for tissue repair, disease modelling and new drug development. In the past two decades, stem cells have also been identified in various body fluids, including urine, peripheral blood, umbilical cord blood, amniotic fluid, synovial fluid, breastmilk and menstrual blood. These body fluid-derived stem cells (BFSCs) have stemness properties comparable to those of other adult stem cells and, similarly to tissue-derived stem cells, show cell surface markers, multi-differentiation potential and immunomodulatory effects. However, BFSCs are more easily accessible through non-invasive or minimally invasive approaches than solid tissue-derived stem cells and can be isolated without enzymatic tissue digestion. Additionally, BFSCs have shown good versatility in repairing genitourinary abnormalities in preclinical models through direct differentiation or paracrine mechanisms such as pro-angiogenic, anti-apoptotic, antifibrotic, anti-oxidant and anti-inflammatory effects. However, optimization of protocols is needed to improve the efficacy and safety of BFSC therapy before therapeutic translation.

New Solutions for Old Problems: How Reproductive Tissue Engineering Has Been Revolutionizing Reproductive Medicine

Acquired disorders and congenital defects of the male and female reproductive systems can have profound impacts on patients, causing sexual and endocrine dysfunction and infertility, as well as psychosocial consequences that affect their self-esteem, identity, sexuality, and relationships. Reproductive tissue engineering (REPROTEN) is a promising approach to restore fertility and improve the quality of life of patients with reproductive disorders by developing, replacing, or regenerating cells, tissues, and organs from the reproductive and urinary systems. In this review, we explore the latest advancements in REPROTEN techniques and their applications for addressing degenerative conditions in male and female reproductive organs. We discuss current research and clinical outcomes and highlight the potential of 3D constructs utilizing biomaterials such as scaffolds, cells, and biologically active molecules. Our review offers a comprehensive guide for researchers and clinicians, providing insights into how to reestablish reproductive tissue structure and function using innovative surgical approaches and biomaterials. We highlight the benefits of REPROTEN for patients, including preservation of fertility and hormonal production, reconstruction of uterine and cervical structures, and restoration of sexual and urinary functions. Despite significant progress, REPROTEN still faces ethical and technical challenges that need to be addressed. Our review underscores the importance of continued research in this field to advance the development of effective and safe REPROTEN approaches for patients with reproductive disorders.

Ultrasound-targeted microbubble destruction mediates PDE5i/NO integration for cavernosum remodeling and penile rehabilitation

Erectile dysfunction (ED) caused by cavernous nerve injury (CNI) is refractory to heal mainly ascribed to the adverse remodeling of the penis induced by ineffectual microvascular perfusion, fibrosis, and neurotrophins scarcity in cavernosum. Phosphodiesterase type V inhibitors (PDE5i) have been regarded as an alternative candidate drug for avoiding penile neuropathy. However, the therapeutic efficacy is severely limited due to poor accumulation under systemic medication and endogenous nitric oxide (NO) deficiency in cavernosum. Herein, an innovative liposomal microbubble (MB) loaded with both Sildenafil (one of PDE5i) and NO was designed. Ultrasound-targeted MB destruction (UTMD)-mediated efficient release and integration erectogenic agents into corpus cavernosum with high biosafety. On a bilateral CNI rat model, the multifunctional MB-cooperated UTMD improved microvascular perfusion in penis, simultaneously, alleviated hypoxia and oxidative stress, indicating successful activation of NO-cyclic guanosine monophosphate pathway. Also, evaluation of the endothelial/muscular composition, intracavernosal pressure, and neural integrity in the penis proved that coordinated intervention reversed the abnormal structural remodeling and promoted the recovery of functional erection. Our work demonstrates that MB loading Sildenafil and NO combined with UTMD hold great promise to "awaken" the efficacy of PDE5i in neurogenic ED, which provided a superior option for ensuring penile rehabilitation.

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.

Penile Rehabilitation after Prostate Cancer Treatment: Which Is the Right Program?

The management of sexual complications after treatment of localized prostate cancer, such as erectile dysfunction, changes in the length of the penis, pain during sexual intercourse, and lack of orgasm, is still an unsolved problem with an important impact on patients’ quality of life. In this review, we summarize the current scientific literature about the rehabilitation of erectile dysfunction after prostate cancer treatment. The therapy for penile rehabilitation includes different types of treatments: the combination of phosphodiesterase type 5 inhibitors (PDE5-I) and the vacuum erectile device (VED) are considered first-line treatment options. When therapy begins, the duration of treatment, the dosage and the drug used all play very important roles in the treatment outcome. Intracavernous injection (ICI) therapy represents the second-line option for patients ineligible for PDE5-I therapy. Technological development has led to the emergence of devices for the stimulation of the penis without the use of drugs, such as penile vibratory stimulation (PVS) for stimulation of ejaculation in spinal cord injury and low-intensity extracorporeal shockwave therapy (LIESWT). The rapid diffusion of the latter, thanks to its easy use, attains good results without side effects. The panorama of penile rehabilitation after PC treatments is vast and many studies are needed, especially on new technologies, to find the best therapeutic regimen possible, personalized to the patient’s characteristics and the type of treatment for PC.

Comparison of the therapeutic effects of human umbilical cord blood-derived mesenchymal stem cells and adipose-derived stem cells on erectile dysfunction in a rat model of bilateral cavernous nerve injury

Background: Cavernous nerve injury (CNI) is the leading cause of erectile dysfunction (ED) after radical prostatectomy and pelvic fracture. Transplantation of human adipose-derived stem cells (ASCs) has been widely used to restore erectile function in CNI-ED rats and patients. Umbilical cord blood-derived MSCs (CBMSCs) are similarly low immunogenic but much primitive compared to ASCs and more promising in large-scale commercial applications due to the extensive establishment of cord blood banks. However, whether CBMSCs and ASCs have differential therapeutic efficacy on CNI-ED and the underlying mechanisms are still not clear.

Materials and methods: A bilateral cavernous nerve injury (BCNI) rat model was established by crushing the bilateral cavernous nerves. After crushing, ASCs and CBMSCs were intracavernously injected immediately. Erectile function, Masson staining, and immunofluorescence analyses of penile tissues were assessed at 4 and 12 weeks. PKH-26-labeled ASCs or CBMSCs were intracavernously injected to determine the presence and differentiation of ASCs or CBMSCs in the penis 3 days after injection. In vitro experiments including intracellular ROS detection, mitochondrial membrane potential assay, EdU cell proliferation staining, cell apoptosis assay, and protein chip assay were conducted to explore the underlying mechanism of CBMSC treatment compared with ASC treatment.

Results: CBMSC injection significantly restored erectile function, rescued the loss of cavernous corporal smooth muscles, and increased the ratio of smooth muscle to collagen. PKH-26-labeled CBMSCs or ASCs did not colocalize with endothelial cells or smooth muscle cells in the corpus cavernosum. Moreover, the conditioned medium (CM) of CBMSCs could significantly inhibit the oxidative stress and elevate the mitochondria membrane potential and proliferation of Schwann cells. Better therapeutic effects were observed in the CBMSC group than the ASC group both in vivo and in vitro. In addition, the content of neurotrophic factors and matrix metalloproteinases in CBMSC-CM, especially NT4, VEGF, MMP1, and MMP3 was significantly higher than that of ASC-CM.

Conclusion: Intracavernous injection of CBMSCs exhibited a better erectile function restoration than that of ASCs in CNI-ED rats owing to richer secretory factors, which can promote nerve regeneration and reduce extracellular matrix deposition. CBMSC transplantation would be a promising therapeutic strategy for CNI-ED regeneration in the future.

Photoacoustic image-guided corpus cavernosum intratunical injection of adipose stem cell-derived exosomes loaded polydopamine thermosensitive hydrogel for erectile dysfunction treatment

Stem cell-derived exosomes (SC-EXO) was an emerging therapeutic agent in regenerative medicine. Intratunical injection of SC-EXO is considered as a prospective approach for erectile dysfunction (ED) treatment. However, high vascularization of cavernous body makes effective retention a major challenge for SC-EXO intratunical injection. In this study, a Polydopamine nanoparticles (PDNPs) incorporated poly (ethylene glycol)-poly(ε-caprolactone-co-lactide) (PDNPs-PELA) thermosensitive hydrogels were fabricated by a facile in situ polymerization for intratunical administration of adipose stem cell-derived exosomes (EXO). The hydrogels exhibited sol-gel transition at body temperature. Moreover, the in-situ polymerization of PDNPs using poly (ethylene glycol)-poly(ε-caprolactone-co-lactide) (PELA) block copolymer as a template was found to be more stable dispersion in the gel system. After being encapsulated into the hydrogel, EXO shows sustained release behavior within two weeks. In vivo animal experiments revealed that exosomes released from hydrogel lead to the healing of endothelial cells and neurons, increase of the cavity's pressure, thereby restoring the erectile function. In particular, since the PDNPs in thermosensitive gels have excellent photoacoustic performance, the hydrogel can be accurately delivered into the tunica albuginea by the guidance of real-time photoacoustic imaging. These results suggest that the as-prepared PDNPs-PELA has a promising future as an injectable exosome carrier for ED treatment.

•

A temperature-sensitive hydrogel with photoacoustic activity was developed for intratunical injection by in-situ polymerization.

•The exosomes encapsulated in the hydrogel can be slowly released and effectively restore damaged nerve and vascular endothelial cells.

•The injection guided by photoacoustic images realizes accurate puncture and real-time filling detection of hydrogel in the corpus cavernosum.

Stem Cell and Gene-Based Therapy for Erectile Dysfunction: Current Status and Future Needs

Erectile dysfunction affects an increasing number of men. The mainstays of management include oral medications, local erectogenic agents, and surgical placement of prosthetic devices. Newer technologies such as stem cell and gene therapy have been investigated as a means to restore spontaneous erectile capacity. Mesenchymal stem cells are thought to produce a local immunomodulatory and pro-repair milieu at the area of injury or needed repair. Gene therapy involves targeting the erectogenic pathway to augment factors involved in producing a natural erection. Such therapies are considered experimental and should be used in the setting of a clinical trial with appropriate oversight.

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.

Beneficial Effects of Human Umbilical Cord Blood Mononuclear Cells on Persistent Erectile Dysfunction After Treatment of 5-Alpha Reductase Inhibitor in Rats

BACKGROUND

Effects of human umbilical cord blood (HUCB) as a valuable source for stem cell-based therapies have not been studied in persistent post-5-alpha reductase inhibitors (5ARI) erectile dysfunction (PPED).

AIM

To determine the effect of intracavernosal injection of HUCB mononuclear cells (MNCs) on ED associated with dutasteride treatment.

METHODS

Twenty five adult male Sprague-Dawley rats were divided into 5 groups (n = 5 per group): (i) control, (ii) 8-week dutasteride (0.5 mg/kg/day, in drinking water), (iii) 12-week dutasteride, (iv) 8-week dutasteride+HUCB-MNCs (1 × 10⁶) and (v) 12-week dutasteride+HUCB-MNCs. HUCB-MNCs were administered intracavernosally after eight weeks of dutasteride treatment. Experiments were performed at 4 weeks following the injection of HUCB-MNCs. Erectile responses and isometric tension of corpus cavernosum (CC) were measured. The protein expressions of phosphodiesterase type 5 (PDE5), endothelial nitric oxide synthase (eNOS), neuronal NOS (nNOS), hypoxia-inducible factor (HIF)-1α and smooth muscle/collagen contents in penile tissue were evaluated by Western blotting, immunohistochemistry, and Masson's trichrome staining, respectively.

MAIN OUTCOME

In vivo erectile function, in vitro relaxant and contractile responses of CC, protein expression and localization of PDE5, eNOS, nNOS, HIF-1α, and smooth muscle content in penile tissue.

RESULTS

Erectile responses in the dutasteride-treated groups were significantly decreased compared with controls (P < .001), persisting after 4-wk of washout. HUCB-MNCs restored diminished intracavernosal pressure responses, acetylcholine-, sodium nitroprusside-, sildenafil-induced relaxations, and increased phenylephrine and electrical field stimulation (EFS)-induced contractions. Decreased EFS-induced relaxations in dutasteride-treated groups were not restored by HUCB-MNCs. Increased PDE5 and reduced nNOS expressions in dutasteride groups were restored by HUCB-MNCs in the 12-week dutasteride group. eNOS and HIF-1α protein expression and serum total and free testosterone  levels were similar among groups. HUCB-MNCs reversed the decreased smooth muscle/collagen ratio in dutasteride-treated tissues. There was a significant increase in PDE5 and HIF-1α staining in 8-week dutasteride animals.

CLINICAL TRANSLATION

This study demonstrates the corrective potential of HUCB-MNCs on some persistent structural and functional deterioration caused by 5ARI treatment in rats, which may encourage further evaluation of HUCB-MNCs in men with PPED.

STRENGTHS AND LIMITATIONS

Therapeutic application of intracavernosal HUCB-MNCs is a novel approach for the rat model of post-5ARI ED. Lack of serum and tissue dihydrotestosterone measurements, vehicle injections and characterization of the cells remain limitations of our study.

CONCLUSION

The persistent ED after prolonged administration of dutasteride in rats is reversed by HUCB-MNC treatment, which holds promise as a realistic therapeutic modality for this type of ED. Oztekin CV, Yilmaz-Oral D, Kaya-Sezginer E, et al. Beneficial Effects of Human Umbilical Cord Blood Mononuclear Cells on Persistent Erectile Dysfunction After Treatment of 5-Alpha Reductase Inhibitor in Rats. J Sex Med 2021;18:889-899.

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.

Availability of platelet-rich plasma for treatment of erectile dysfunction and associated costs and efficacy: A review of current publications and Canadian data

INTRODUCTION

Platelet-rich plasma (PRP) is an increasingly used unconventional treatment option for erectile dysfunction (ED). The validity of PRP as a potential treatment for ED has been proposed in limited human trials. Furthermore, the costs associated with PRP for ED treatment are not readily promoted to patients. The goal of this review was to determine the efficacy and costs of PRP based on currently available literature and Canadian data.

METHODS

A comprehensive literature review of available PRP studies and current published data pertaining to cost, availability, and provider clinics globally was conducted using the PubMed database. Physicians offering genital PRP in Canada were identified using internet searches and PRP provider directories. Physician qualifications, clinic locations, and cost information were obtained from provider websites and telephone calls to identified clinics.

RESULTS

Availability of PRP injections offered for treating ED is increasing globally. There are currently no peer-reviewed publications to substantiate anecdotal evidence pertaining to the efficacy of PRP as a viable treatment option for ED patients. Our results indicate 19 providers for PRP injections in Canada, costing on average $1777 CAD per injection. No providers were affiliated with academic institutions and providers varied in their area of clinical speciality and training.

CONCLUSIONS

To our knowledge, there is currently no research underway investigating the clinical efficacy of PRP for ED treatment despite its broad availability and significant cost. Patients should be informed of the lack of substantiated efficacy and safety data, as the reliability of PRP treatments requires further evaluation.

Administration of secretome from human placental stem cell-conditioned media improves recovery of erectile function in the pelvic neurovascular injury model

Human placental stem cells (PSCs) enhance histological and functional recovery in a rodent erectile dysfunction (ED) model. We tested the hypothesis that bioactive factors secreted by PSC (i.e., the secretome) mediate functional recovery and that acellular-conditioned media (CM) from PSC culture (PSC-CM) could be used independently to facilitate functional and histological recovery. To identify factors relative to efficacy of PSC, a comparison of CM from PSC and three additional human stem cell populations was performed. CM from human PSC, amniotic fluid stem cells (AFSCs), adipose-derived stem cells (ADSC), and human umbilical vein endothelial cells (HUVECs) was assayed using a semi-quantitative human cytokine antibody array. Male rats, after surgically created ED by neurovascular injury, were randomly divided into four groups: vehicle control (phosphate-buffered saline [PBS]), PSC, PSC-CM, and serum-free media control (SFM) as control. Functional data on intracorporal and mean arterial pressure were obtained, and histological architecture was examined 6 weeks after single injection. PSCs were found to secrete at least 27 cytokines and growth factors at a significantly higher level than the other three cell types. Either single injection of PSC-CM or PSC significantly improved erectile functional recovery and histological architecture compared with SFM or PBS. Injection of the secretome isolated from human PSC improves erectile functional recovery and histological structure in a rat model of neurovascular injury-induced ED. Further characterization of the unique protein expression within the PSC-CM may help to identify the potential for a novel injectable cell-free therapeutic for applicable patients.

Combined Transplantation of Adipose Tissue-Derived Stem Cells and Endothelial Progenitor Cells Improve Diabetic Erectile Dysfunction in a Rat Model

Erectile dysfunction (ED) is a common complication in men suffered with diabetic mellitus. Stem cell transplantation is a promising strategy for the treatment of diabetic ED (DED). In this study, we evaluated whether combined transplantation of adipose tissue-derived stem cells (ADSCs) and endothelial progenitor cells (EPCs) could improve the erectile function of the DED rat model. DED rats were induced via intraperitoneal injection of streptozotocin (50 mg/kg), and ED was screened by apomorphine (100 mg/kg). DED rats were divided into 4 groups (n = 14 each): DED, ADSC, EPC, and ADSC/EPC group. Another 14 age-matched male SD rats with normal erectile function were served as the normal group. The normal group and the DED group were received intracavernous injection with phosphate-buffered saline (PBS). And the other groups were received intracavernous injection with ADSCs (1 × 10⁶), EPCs (1 × 10⁶), and ADSCs/EPCs (0.5 × 10⁶/0.5 × 10⁶), respectively. The total intracavernous pressure (ICP) and mean arterial pressure (MAP) were recorded at day 28 after injection. The endothelium, smooth muscle, and penile dorsal nerves were assessed within cavernoursal tissue. On day 28 after injection, the ADSC/EPC group displayed more significantly enhanced ICP and ICP/MAP than the DED or ADSC or EPC group (p < 0.05). Immunofluorescent analysis and western blot demonstrated that the improvement of erectile function in the ADSC/EPC5 group was associated with increased expression of endothelial marker (CD31) and the correction of eNOS-cGMP-NO signaling. More 5-ethynyl-2′-deoxyuridine- (EdU-) positive EPCs could be found lining in the cavernous endothelial layer in the ADSC/EPC group than the EPC group, which was attributed to the paracrine of vascular endothelial growth factor (VEGF) and stromal-derived factor-1 (SDF-1) by ADSCs. Combined transplantation of ADSCs and EPCs has a synergic effect in repairing the endothelial function of DED rats, and the underlying mechanism might be the paracrine of VEGF and SDF-1 by ADSCs, which improves the recruitment and proliferation of EPCs in the cavernosum.

Intracavernous injection of size-specific stem cell spheroids for neurogenic erectile dysfunction: Efficacy and risk versus single cells

BACKGROUND

Intracavernous injection (ICI) of adipose-derived stem cells (ADSCs) has been demonstrated promising for neurogenic erectile dysfunction (ED). However, due to the sponge-like structure of corpus cavernosum (CC) with abundant vessels, ICI was indeed like intravenous injection. Thus, the cell escaping may be a concern of safety and limited therapy, but the issue has not been clearly demonstrated yet.

METHODS

Suspensions of free ADSCs (FAs) and ADSCs-based spheroids (ASs) with suitable size were intracavernously injected at doses of 0.5, 1, 2, or 4 million cells. The cell loss and safety after ICI, erectile function and histopathologic change, etc. were analyzed with multimodality of methods.

FINDINGS

Most FAs escaped from sponge-like CC after ICI due to their small size, weakening stem-cell therapeutic efficacy. Worse still, the escaped cells were shown to cause widespread pulmonary embolism (PE), and even death in some animals. Further, it was founded that the therapeutic effect of FAs may be ascribed to the larger cell clusters which spontaneously aggregated before ICI and were trapped within CC after ICI. In comparison, cell loss and PE were significantly avoided by transplanting ASs. Importantly, better therapeutic outcomes were detected after ICI of ASs when compared to FAs with the same cell number.

INTERPRETATION

Transplantation of size-specific ASs instead of single-cell suspension of FAs for neurogenic ED may be a wiser choice to achieve steady therapeutic outcome and to reduce risks for the future clinical application. FUND: This work was supported by the National Natural Science Foundation of China (81701432) (to Y. Xu). Youth Training Project for Medical science (16QNP129) and Beijing Nova Program of science and technology (Z171100001117115) (to Z. Liu).

Dynamic Changes in Erectile Function and Histological Architecture After Intracorporal Injection of Human Placental Stem Cells in a Pelvic Neurovascular Injury Rat Model

INTRODUCTION

The human placenta provides a bountiful and noncontroversial source of stem cells which have the potential for regeneration of injured tissue. These cells may restore erectile function after neurovascular tissue injury such as that seen in radical pelvic surgeries and pelvic trauma.

AIM

To determine the effect of human placenta-derived stem cells on erectile function recovery and histological changes at various time points in a cavernous nerve injury rat model and to study the fate of injected stem cells throughout the regenerative process.

METHODS

Human placental stem cells (PSCs) were dual labeled with monomeric Katushka far red fluorescent protein (mKATE)-renLUC using a lentivirus vector. A pelvic neurovascular injury-induced erectile dysfunction model was established in male, athymic rats by crushing the cavernous nerves and ligating the internal pudendal neurovascular bundles, bilaterally. At the time of defect creation, nonlabeled PSCs were injected into the corpus cavernosum at a concentration of 2.5 × 10⁶ cells/0.2 mL. The phosphate-buffered saline-treated group served as the negative control group, and age-matched rats (age-matched controls) were used as the control group. Erectile function, histomorphological analyses, and Western blot were assessed at 1, 6, and 12 weeks after model creation. The distribution of implanted, dual-labeled PSCs was monitored using an in vivo imaging system (IVIS). Implanted cells were further tracked by detection of mKATE fluorescence in histological sections.

MAIN OUTCOME MEASURE

The main outcome measure includes intracavernous pressure/mean arterial pressure ratio, neural, endothelial, smooth muscle cell regeneration, mKATE fluorescence, and IVIS imaging.

RESULTS

The ratio of intracavernous pressure to mean arterial pressure significantly increased in PSC-injected rats compared with phosphate-buffered saline controls (P < 0.05) at the 6- and 12-week time points, reaching 72% and 68% of the age-matched control group, respectively. Immunofluorescence staining and Western blot analysis showed significant increases in markers of neurons (84.3%), endothelial cells (70.2%), and smooth muscle cells (70.3%) by 6 weeks in treatment groups compared with negative controls. These results were maintained through 12 weeks. IVIS analysis showed luminescence of implanted PSCs in the injected corpora immediately after injection and migration of cells to the sites of injury, including the incision site and periprostatic vasculature by day 1. mKATE fluorescence data revealed the presence of PSCs in the penile corpora and major pelvic ganglion at 1 and 3 days postoperatively. At 7 days, immunofluorescence of penile PSCs had disappeared and was diminished in the major pelvic ganglion.

CLINICAL IMPLICATIONS

Placenta-derived stem cells may represent a future "off-the-shelf" treatment to mitigate against development of erectile dysfunction after radical prostatectomy or other forms of pelvic injury.

STRENGTH & LIMITATIONS

Single dose injection of PSCs after injury resulted in maximal functional recovery and tissue regeneration at 6 weeks, and the results were maintained through 12 weeks. Strategies to optimize adult stem cell therapy might achieve more effective outcomes for human clinical trials.

CONCLUSION

Human PSC therapy effectively restores the erectile tissue and function in this animal model. Thus, PSC therapy may provide an attractive modality to lessen the incidence of erectile dysfunction after pelvic neurovascular injury. Further improvement in tissue regeneration and functional recovery may be possible using multiple injections or systemic introduction of stem cells. Gu X, Thakker PU, Matz EL, et al. Dynamic Changes in Erectile Function and Histological Architecture After Intracorporal Injection of Human Placental Stem Cells in a Pelvic Neurovascular Injury Rat Model. J Sex Med 2020;17:400-411.

In vivo tracking on longer retention of transplanted myocardin gene-modified adipose-derived stem cells to improve erectile dysfunction in diabetic rats

BACKGROUND

Stem cell therapy has revealed a promising future for treating erectile dysfunction (ED), but the fate and curative mechanism of intracavernosal transplanted stem cells are under further exploration. This study aimed to demonstrate the effects of myocardin gene modification on improving erectile function and prolonging the retention of implanted adipose-derived stem cells (ASCs) using in vivo small animal imaging.

METHODS

ASCs were isolated, cultured, and identified by flow cytometry and osteogenic and adipogenic induction. The effects of gene modification on cell proliferation, apoptosis, and contraction were determined by CCK-8, EdU, flow cytometry, and collagen gel lattice contraction assays as well as confocal microscopy. A total of 20 normal and 60 diabetes mellitus ED to (DMED) Sprague-Dawley rats were recruited to the 7 day and 21 day groups. Each group contained subgroups of 10 rats each: the negative control (NC), DMED + ASCs plus Ad-Luc-Myocardin, DMED + ASCs plus Ad-Luc, and DMED + phosphate buffer solution (PBS) groups. Erectile function was evaluated with the intracavernosal pressure/mean arterial pressure (△ICP/MAP) ratio. In vivo small animal imaging and an EdU cell tracking strategy were introduced to detect the transplanted ASCs, and IHC and WB were performed to assess smooth muscle cell protein levels.

RESULTS

The ASCs expressed high CD29 and CD90 and scant CD45, while the multi-induction potential was verified by oil red O and alizarin red staining. Gene transfection of myocardin had no significant influence on ASC apoptosis but inhibited cell proliferation and promoted cell contraction. Myocardin combined with ASCs enhanced the therapeutic potential of ASCs for improving the △ICP/MAP ratio as well as α-SMA and calponin expression. In vivo imaging confirmed that ASCs resided within the cavernous body in 21 days, while only a few red EdU dots were detected.

CONCLUSIONS

Myocardin induced ASC differentiation towards smooth muscle-like cells and enhanced the therapeutic potential of ASCs for ameliorating ED in STZ-induced diabetic rats. Notably, in vivo small animal tracking was an effective strategy for monitoring the implanted stem cells, and this strategy might have advantages over traditional EdU assays.