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

Human urine stem cells protect against cyclophosphamide-induced premature ovarian failure by inhibiting SLC1A4-mediated outflux of intracellular serine in ovarian granulosa cells

BACKGROUND

Cyclophosphamide (CTX) is the first-line medication for the treatment of breast cancer, although it potentially leads to severe ovarian dysfunction and even premature ovarian failure (POF). However, the mechanism of CTX-induced POF remains unclear. Mesenchymal stem cell-based therapy has been wildly used for treating numerous diseases. Therefore, our study aims to elucidate the underlying mechanism of CTX-induced POF and to explore the therapeutic effect of human urine stem cells (hUSCs) in POF.

METHODS

CTX-induced POF or ovarian granulosa cell (GCs) apoptosis were treated with hUSCs and their exosomes in vitro and in vivo. Morphological, histological, and functional alternations were examined using multiple approaches. The effector molecules of hUSC-derived exosomes (hUSC-Exo) were determined by differential expression analysis in the ovaries. The target genes of miRNA were accessed by transcriptome sequencing in GCs, and the underlying mechanisms were further elucidated.

RESULTS

hUSCs remarkably inhibited CTX-induced apoptosis and promoted the proliferation of GCs, respectively. In addition, we observed that miR-27b-3p was highly expressed in hUSC-Exo and markedly suppressed CTX-induced GC apoptosis by specifically inhibiting the expression of SLC1A4, a serine transporter, in ovarian GCs, which, in turn, elevated the concentration of the intracellular serine by inhibiting the outflux of cellular serine. More importantly, the knockdown of SLC1A4 or simple supplementation of serine suppressed CTX-induced apoptosis of GCs. Finally, we demonstrated that CTX-induced apoptosis of ovarian GCs was essential for POF by reducing the intracellular serine concentration via elevating the expression of SLC1A4, whereas hUSCs protected against CTX-induced POF via miR-27b-3p/SLC1A4/serine axis-mediated activation of the PI3K/AKT/mTOR signaling pathway.

CONCLUSIONS

Our study suggests that hUSC-based cell therapy or simple supplementation of serine may provide an efficient therapeutic approach for the prevention and treatment of CTX-induced POF clinically.

Yes-Associated Protein Promotes Endothelial-Mesenchymal Transition to Mediate Diabetes Mellitus Erectile Dysfunction by Phosphorylating Smad3

PURPOSE

The main objective of this study is to elucidate the role of endothelial-mesenchymal transition (EndMT) regulated by yes-associated protein (YAP) on diabetes mellitus erectile dysfunction (DMED).

MATERIALS AND METHODS

High concentrations of glucose and palmitic acid (HGP) culturing simulated a diabetic condition in vitro. Cell proliferation, migration, tube formation, and marker gene changes of rat cavernous endothelial cells (RCECs) were measured after YAP overexpression or knockdown. Erectile function and histological outcomes were evaluated in vivo.

RESULTS

Nuclear YAP in RCECs was significantly increased after pretreatment with HGP. YAP overexpression enhanced the cell proliferation (0.236±0.004 vs. 0.148±0.008, p<0.001), migration (1.908±0.099 vs. 1.000±0.116, p<0.001), and tube formation (290.6±10.96 and 21,440.3±762.9 vs. 175.0±24.82 and 13,538.6±1,819.0, p<0.001) compared to the control group. Moreover, the ratios of intracavernous pressure (ICP) to mean arterial pressure (MAP) (0.642±0.051 vs. 0.850±0.070, p<0.05), and smooth muscle to collagen (0.155±0.010 vs. 0.274±0.023, p<0.01) were decreased in rats with YAP overexpression. The effects of HGP on CD31, eNOS, CD34, VE-cadherin, vimentin, α-SMA, and p-Smad3 expression were abrogated by inhibiting YAP in RCECs. YAP knockdown also restored the ICP/MAP (0.597±0.019 vs. 0.346±0.033, p<0.01), smooth muscle/collagen (0.13±0.010 vs. 0.08±0.026, p<0.05) and p-Smad3/Smad3 (1.61±0.291 vs. 3.26±0.332, p<0.01) ratios in type 2 diabetic rats.

CONCLUSIONS

YAP promotes EndMT to impair erectile function in type 2 diabetic rats by phosphorylating Smad3, providing a new strategy for treating DMED.

An update on the use of stem cell therapy for erectile dysfunction

Objective

This systematic review aimed to analyze animal and human trial data to better understand the efficacy of stem cell therapy (SCT) for erectile dysfunction (ED) and the obstacles that may hinder its application in this field.

Methods

We searched electronic databases, including PubMed and Scopus, for published studies with the Medical Subject Heading terms of "erectile dysfunction" (AND) "stem cell therapy" (OR) "erectile dysfunction" (AND) "clinical trial of stem cell therapy" (OR) "stem cell therapy" (AND) "sexual dysfunction". The search was limited to English-language journals and full papers only. The initial search resulted in 450 articles, of which 90 relevant to our aims were included in the analysis.

Results

ED is a multifactorial disease. Current treatment options rely on pharmacotherapy as well as surgical options. Patients may have side effects or unsatisfactory results following the use of these treatment options. SCT may restore pathophysiological changes leading to ED rather than treating the symptoms. It has been evaluated in animal models and shown promising results in humans. Results confirm that SCT does improve erectile function in animals with different types of SC use. In humans, evidence showed promising results, but the trials were heterogeneous and limited mainly by a lack of randomization and the small sample size. Many challenges could limit future research in this field, including ethical dilemmas, regulation, patient recruitment, the cost of therapy, and the lack of a standardized SCT regimen. Repairing and possibly replacing diseased cells, tissue, or organs and eventually retrieving normal function should always be the goals of any therapy, and this can only be guaranteed by SCT.

Conclusion

SCT is a potential and successful treatment for ED, particularly in patients who are resistant to the classic therapy. SCT may promote nerve regeneration and vascular cell regeneration, not only symptomatic treatment.

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.

Urine-derived stem cell therapy for diabetes mellitus and its complications: progress and challenges

Diabetes mellitus (DM) is a chronic and relentlessly progressive metabolic disease characterized by a relative or absolute deficiency of insulin in the body, leading to increased production of advanced glycosylation end products that further enhance oxidative and nitrosative stresses, often leading to multiple macrovascular (cardiovascular disease) and microvascular (e.g., diabetic nephropathy, diabetic retinopathy, and neuropathy) complications, representing the ninth leading cause of death worldwide. Existing medical treatments do not provide a complete cure for DM; thus, stem cell transplantation therapy has become the focus of research on DM and its complications. Urine-derived stem cells (USCs), which are isolated from fresh urine and have biological properties similar to those of mesenchymal stem cells (MSCs), were demonstrated to exert antiapoptotic, antifibrotic, anti-inflammatory, and proangiogenic effects through direct differentiation or paracrine mechanisms and potentially treat patients with DM. USCs also have the advantages of simple noninvasive sample collection procedures, minimal ethical issues, low cost, and easy cell isolation methods and thus have received more attention in regenerative therapies in recent years. This review outlines the biological properties of USCs and the research progress and current limitations of their role in DM and related complications. In summary, USCs have shown good versatility in treating hyperglycemia-impaired target organs in preclinical models, and many challenges remain in translating USC therapies to the clinic.

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.

Regenerative therapies as a potential treatment of erectile dysfunction

Erectile dysfunction (ED) is the most common sexual dysfunction disease in adult males. ED can be caused by many factors, such as vascular disease, neuropathy, metabolic disturbances, psychosocial causes, and side effects of medications. Although current oral phosphodiesterase type 5 inhibitors can achieve a certain effect, they cause temporary dilatation of blood vessels with no curative treatment effects. Emerging targeted technologies, such as stem cell therapy, protein therapy, and low-intensity extracorporeal shock wave therapy (Li-ESWT), are being used to achieve more natural and long-lasting effects in treating ED. However, the development and application of these therapeutic methods are still in their infancy, and their pharmacological pathways and specific mechanisms have not been fully discovered. This article reviews the preclinical basic research progress of stem cells, proteins, and Li-ESWT therapy, as well as the current status of clinical application of Li-ESWT therapy.

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.