Therapeutic potential of salidroside in type I diabetic erectile dysfunction: Attenuation of oxidative stress and apoptosis via the Nrf2/HO-1 pathway.

The primary objective of this work was to delve into the potential therapeutic advantages and dissect the molecular mechanisms of salidroside in enhancing erectile function in rats afflicted with diabetic microvascular erectile dysfunction (DMED), addressing both the whole-animal and cellular dimensions.We established a DMED model in Sprague‒Dawley (SD) rats and conducted in vivo experiments. The DMED rats were administered varying doses of salidroside, the effects of which on DMED were compared. Erectile function was evaluated by applying electrical stimulation to the cavernous nerves and measuring intracavernous pressure in real time. The penile tissue underwent histological examination and Western blotting. Hydrogen peroxide (H2O2) was employed in the in vitro trial to induce an oxidative stress for the purpose of identifying alterations in cell viability. The CCK-8 assay was used to measure the viability of corpus cavernous smooth muscle cells (CCSMCs) treated with vs. without salidroside. Flow cytometry was utilized to detect alterations in intracellular reactive oxygen species (ROS). Apoptosis was assessed through Western blotting and TdT-mediated dUTP nick-end labelling (TUNEL). Animal and cellular experiments indicate that the Nrf2/HO-1 signalling pathway may be upregulated by salidroside, leading to the improvement of erectile function in diabetic male rats by alleviating oxidative stress and reducing apoptosis in corpus cavernosum tissue.

miR-200a-3p-enriched MSC-derived extracellular vesicles reverse erectile function in diabetic rats by targeting Keap1.

BACKGROUND: The administration of mesenchymal stem cells (MSCs) through intracavernous injection is a potential therapeutic approach for managing diabetes mellitus-induced erectile dysfunction (DMED). However, pulmonary embolism and tumorigenicity are fatal adverse events that limit the clinical application of MSCs. In this study, we examined the therapeutic efficacy and potential mechanism of MSC-derived extracellular vesicles (MSC-EVs). METHODS: In this study, forty 8-week-old male SpragueDawley (SD) rats were utilised. In the control group, ten rats were administered an intraperitoneal injection of PBS. STZ (60 mg/kg) was intraperitoneally injected into the remaining rats to establish a diabetes mellitus (DM) model. Afterwards, the diabetic rats were divided into three groups at random: the DM group (intracavernosal injection of PBS), the EVs group (intracavernosal injection of MSC-EVs), and the EVs-200a group (intracavernosal injection of miR-200a-3p-enriched extracellular vesicles). Erectile function was determined by measuring intracavernous pressure in real time and utilising electrical stimulation of the cavernous nerves. The smooth muscle content was evaluated through the investigation of penile tissue using immunofluorescence staining, Masson's trichrome staining, and western blotting after euthanasia. Superoxide dismutase (SOD), malondialdehyde (MDA), and glutathione (GSH) levels in the corpus cavernosum were measured via ELISA. In vitro, hydrogen peroxide (H2O2) was used to induce oxidative stress. The viability of corpus cavernosum smooth muscle cells (ccSMCs) incubated with or without H2O2 was measured using a CCK8 assay. Flow cytometry was used to assess the levels of reactive oxygen species (ROS) and apoptosis in ccSMCs. Furthermore, a dual-luciferase reporter assay was performed to validate the relationship between miR-200a-3p and Keap1. RESULTS: Reversal of erectile function was observed in the EVs groups, especially in the EVs-200a group. DM increased the MDA level and decreased the SOD and GSH levels. In the DM group, the expression of alpha-smooth muscle actin (α-SMA) and smooth muscle 22 alpha (SM22α) was decreased, and the expression of osteopontin (OPN) was increased. Western blotting revealed decreased Nrf2, HO-1, and Bcl2 expression and increased Keap1, Bax and cleaved caspase3 expression in the cavernous tissue. miR-200a-3p-enriched extracellular vesicles (EVs-200a) reversed these changes and inhibited the loss of smooth muscle content and cavernous fibrosis. In vitro, H2O2 induced high ROS levels in ccSMCs and increased apoptosis, and these effects reversed by EVs-200a. H2O2 reduced Nrf2, HO-1, and Bcl2 expression and increased Keap1, Bax and cleaved caspase-3 expression, and these effects were reversed by MSC-EVs, especially EVs-200a. The of dual-luciferase reporter assay results indicated that miR-200a-3p directly targeted Keap1 in a negative manner. CONCLUSION: MSC-EVs, especially EVs-200a, alleviated erectile dysfunction in diabetic rats through the regulation of phenotypic switching, apoptosis and fibrosis. Mechanistically, miR-200a-3p targeted the Keap1/Nrf2 pathway to attenuate oxidative stress in diabetic rats.

A low testosterone level impairs erectile function by increasing endocan expression in rat penile corpus cavernosum.

BACKGROUND: The mechanism by which a state of low testosterone leads to erectile dysfunction (ED) has not been determined. Endocan is a novel marker of endothelial function. However, whether endocan is involved in the regulation of erectile function under low testosterone levels remains unclear. AIM: In this study we sought to determine whether a low-testosterone state inhibits erectile function by regulating endocan expression in the endothelial cells of the rat penile corpus cavernosum. METHODS: Thirty-six male Sprague-Dawley rats aged 8 weeks were randomly assigned to 6 groups (n = 6 per group) as follows: (1) control, (2) castration, (3) castration + testosterone treatment (treated with 3 mg/kg testosterone propionate per 2 days), (4) control + transfection (4 weeks after castration, injected with lentiviral vector (1 × 108 transduction units/mL, 10 µL), (5) castration + transfection, or (6) castration + empty transfection. One week after the injection, we measured the maximal intracavernous pressure/mean arterial pressure (ICPmax/MAP), serum testosterone and nitric oxide (NO) levels, and the expression of endocan, phospho-endothelial NO synthase (p-eNOS), eNOS, phospho-protein kinase B (p-AKT), and AKT in the rat penile corpus cavernosum. OUTCOMES: Under a low-androgen state, the expression of endocan in the rat penile corpus cavernosum was significantly increased, which inhibited the AKT/eNOS/NO signaling pathway and resulted in ED. RESULTS: In the castration group, the expression of endocan in the rat penile corpus cavernosum was significantly higher than that in the control group (P < .05). Additionally, the levels of p-AKT/AKT, p-eNOS/eNOS, and NO in the rat penile corpus cavernosum and ICPmax/MAP were significantly lower in the castration group than in the control group (P < .05). In the castration + transfection group compared with the castration group there was a significant decrease in the expression of endocan (P < .05) and an increase in the ratios of p-AKT/AKT, p-eNOS/eNOS, and ICPmax/MAP (P < .05) in the rat penile corpus cavernosum. CLINICAL IMPLICATIONS: Downregulating the expression of endocan in the penile corpus cavernosum may be a feasible approach for treating ED caused by hypoandrogenism. STRENGTHS AND LIMITATIONS: The results of this study indicte that endocan may affect NO levels and erectile function through multiple signaling pathways, but further experiments are needed to clarify the relationship between endocan and androgens. CONCLUSION: A low-testosterone state inhibits the AKT/eNOS/NO signaling pathway by increasing the expression of endocan in the rat penile corpus cavernosum and impairing erectile function in rats. Decreasing the expression of endocan in the penile corpus cavernosum can improve erectile function in rats with low testosterone levels.

Neutrophil extracellular traps promote erectile dysfunction in rats with diabetes mellitus by enhancing NLRP3-mediated pyroptosis.

Erectile dysfunction (ED) is the most prevalent consequences in men with diabetes mellitus (DM). Recent studies demonstrates that neutrophil extracellular traps (NETs) play important roles in DM and its complications. Nevertheless, whether NETs are involved in ED remains unknown. This work intended to explore the role and mechanisms of NETs in ED in the context of DM. Here, we observed that NET generation and pyroptosis were promoted in DM rats with ED compared with controls. Mechanistically, NETs facilitated NLRP3 inflammasome activation and subsequently triggered pyroptosis under high glucose stress, ultimately leading to ED. Intriguingly, DNase I (a NET degrading agent) alleviated ED and corpus cavernosum injury in DM rats. Overall, NETs might induce ED in DM by promoting NLRP3-mediated pyroptosis in the corpus cavernosum.

Role of hydrogen sulfide in the male reproductive system.

As an important gas signaling molecule, hydrogen sulfide (H2S) affects multiple organ systems, including the nervous, cardiovascular, digestive, and genitourinary, reproductive systems. In particular, H2S not only regulates female reproductive function but also holds great promise in the treatment of male reproductive diseases and disorders, such as erectile dysfunction, prostate cancer, varicocele, and infertility. In this review, we summarize the relationship between H2S and male reproductive organs, including the penis, testis, prostate, vas deferens, and epididymis. As lower urinary tract symptoms have a significant impact on penile erection disorders, we also address the potential ameliorative effects of H2S in erectile dysfunction resulting from bladder disease. Additionally, we discuss the regulatory role of H2S in cavernous smooth muscle relaxation, which involves the NO/cGMP pathway, the RhoA/Rho-kinase pathway, and K+ channel activation. Recently, various compounds that can alleviate erectile dysfunction have been reported to be at least partly dependent on H2S. Therefore, understanding the role of H2S in the male reproductive system may help develop novel strategies for the clinical treatment of male reproductive system diseases.

LncRNA MALAT1 facilitates BM-MSCs differentiation into endothelial cells and ameliorates erectile dysfunction via the miR-206/CDC42/PAK1/paxillin signalling axis.

BACKGROUND: Erectile dysfunction (ED) is a common male sexual dysfunction, with an increasing incidence, and the current treatment is often ineffective. METHODS: Vascular endothelial growth factor (VEGFA) was used to treat bone marrow-derived mesenchymal stem cells (BM-MSCs), and their cell migration rates were determined by Transwell assays. The expression of the von Willebrand Factor (vWF)VE-cadherin, and endothelial nitric oxide synthase(eNOS) endothelial markers was determined by qRT‒PCR and Western blot analyses. The MALAT1-induced differentiation of BM-MCs to ECs via the CDC42/PAK1/paxillin pathway was explored by transfecting VEGFA-induced BM-MSC with si-MALAT1 and overexpressing CDC42 and PAK1. The binding capacity between CDC42, PAK1, and paxillin in VEGFA-treated and non-VEGFA-treated BM-MSCs was examined by protein immunoprecipitation. MiR-206 was overexpressed in VEGFA-induced BM-MSC, and the binding sites of MALAT1, miR-206, and CDC42 were identified using a luciferase assay. Sixty male Sprague‒Dawley rats were divided into six groups (n = 10/group). DMED modelling was demonstrated by APO experiments and was assessed by measuring blood glucose levels. Erectile function was assessed by measuring the intracavernosa pressure (ICP) and mean arterial pressure (MAP). Penile erectile tissue was analysed by qRT‒PCR, Western blot analysis, and immunohistochemical staining. RESULTS: MALAT1 under VEGFA treatment conditions regulates the differentiation of BM-MSCs into ECs by modulating the CDC42/PAK1/paxillin axis. In vitro experiments demonstrated that interference with CDC42 and MALAT1 expression inhibited the differentiation of BM-MSCs to ECs. CDC42 binds to PAK1, and PAK1 binds to paxillin. In addition, CDC42 in the VEGFA group had a greater ability to bind to PAK1, whereas PAK1 in the VEGFA group had a greater ability to bind to paxillin. Overexpression of miR-206 in VEGFA-induced BM-MSCs demonstrated that MALAT1 competes with the CDC42 3'-UTR for binding to miR-206, which in turn is involved in the differentiation of BM-MSCs to ECs. Compared to the DMED model group, the ICP/MAP ratio was significantly greater in the three BM-MSCs treatment groups. CONCLUSIONS: MALAT1 facilitates BM-MSC differentiation into ECs by regulating the miR-206/CDC42/PAK1/paxillin axis to improve ED. The present findings revealed the vital role of MALAT1 in the repair of BM-MSCs for erectile function and provided new mechanistic insights into the BM-MSC-mediated repair of DMED.

Single-cell transcriptome analysis of cavernous tissues reveals the key roles of pericytes in diabetic erectile dysfunction.

Erectile dysfunction (ED) affects a significant proportion of men aged 40-70 and is caused by cavernous tissue dysfunction. Presently, the most common treatment for ED is phosphodiesterase 5 inhibitors; however, this is less effective in patients with severe vascular disease such as diabetic ED. Therefore, there is a need for development of new treatment, which requires a better understanding of the cavernous microenvironment and cell-cell communications under diabetic condition. Pericytes are vital in penile erection; however, their dysfunction due to diabetes remains unclear. In this study, we performed single-cell RNA sequencing to understand the cellular landscape of cavernous tissues and cell type-specific transcriptional changes in diabetic ED. We found a decreased expression of genes associated with collagen or extracellular matrix organization and angiogenesis in diabetic fibroblasts, chondrocytes, myofibroblasts, valve-related lymphatic endothelial cells, and pericytes. Moreover, the newly identified pericyte-specific marker, Limb Bud-Heart (Lbh), in mouse and human cavernous tissues, clearly distinguishing pericytes from smooth muscle cells. Cell-cell interaction analysis revealed that pericytes are involved in angiogenesis, adhesion, and migration by communicating with other cell types in the corpus cavernosum; however, these interactions were highly reduced under diabetic conditions. Lbh expression is low in diabetic pericytes, and overexpression of LBH prevents erectile function by regulating neurovascular regeneration. Furthermore, the LBH-interacting proteins (Crystallin Alpha B and Vimentin) were identified in mouse cavernous pericytes through LC-MS/MS analysis, indicating that their interactions were critical for maintaining pericyte function. Thus, our study reveals novel targets and insights into the pathogenesis of ED in patients with diabetes.

Caveolin-1 scaffolding domain-derived peptide enhances erectile function by regulating oxidative stress, mitochondrial dysfunction, and apoptosis of corpus cavernosum smooth muscle cells in rats with cavernous nerve injury.

AIM: Increased corpus cavernosum smooth muscle cells (CCSMCs) apoptosis in the penis due to cavernous nerve injury (CNI) is a crucial contributor to erectile dysfunction (ED). Caveolin-1 scaffolding domain (CSD)-derived peptide has been found to exert potential antiapoptotic properties. However, whether CSD peptide can alleviate CCSMCs apoptosis and ED in CNI rats remains unknown. The study aimed to determine whether CSD peptide can improve bilateral CNI-induced ED (BCNI-ED) by enhancing the antiapoptotic processes of CCSMCs. MAIN METHODS: Fifteen 10-week-old male Sprague-Dawley (SD) rats were randomly classified into three groups: sham surgery (Sham) group and BCNI groups that underwent saline or CSD peptide treatment respectively. At 3 weeks postoperatively, erectile function was assessed and the penis tissue was histologically examined. Furthermore, an in vitro model of CCSMCs apoptosis was established using transforming growth factor-beta 1 (TGF-ß1) to investigate the mechanism of CSD peptide in treating BCNI-ED. KEY FINDINGS: In BCNI rats, CSD peptide significantly prevented ED and decreased oxidative stress, the Bax/Bcl-2 ratio, and the levels of caspase3. TGF-ß1-treated CCSMCs exhibited severe oxidative stress, mitochondrial dysfunction, and apoptosis. However, CSD peptide partially reversed these alterations. SIGNIFICANCE: Exogenous CSD peptide could improve BCNI-ED by inhibiting oxidative stress, the Bax/Bcl-2 ratio, and caspase3 expression in penile tissue. The underlying mechanism might involve the regulatory effects of CSD peptide on oxidative stress, mitochondrial dysfunction, and apoptosis of CCSMCs following CNI. This study highlights CSD peptide as an effective therapy for post-radical prostatectomy ED (pRP-ED).

Exosomes secreted by adipose mesenchymal stem cells overexpressing circPIP5K1C exert.

BACKGROUND: Erectile dysfunction (ED) seriously affects men's normal life, and obstructive sleep apnoea (OSA) has been diagnosed as a causative factor. Currently, exosomes secreted by adipose mesenchymal stem cells (ADSC) have been used in the non-clinical experimental treatment of ED disease with prominent efficacy due to the advantages of high stability and no immune exclusion. METHODS: In this study, chronic intermittent hypoxia (CIH) exposure was used to induce ED-corresponding phenotypes in Sprague Dawley (SD) rats as well as in cavernous smooth muscle cells (CCSMCs). ED symptoms were treated using exosomes secreted by ADSCs overexpressing circPIP5K1C (EXO-circ) injected into the rat corpus cavernosum. RESULTS: EXO-circ has the effect of ameliorating ED induced by CIH exposure in rats, the mechanism of which is to promote the expression of the downstream target gene SMURF1 after adsorption of miR-153-3p through the sponge so that SMURF1 and PFKFB3 occur protein-protein binding and ubiquitination degradation of PFKFB3 appears to inhibit the occurrence of spongiotic smooth muscle cells glycolysis, and to restore the function of the smooth muscle. CONCLUSIONS: These findings show that EXO-circ have a promising therapeutic potential in OSA-induced ED.

Investigating a novel surrogate indicator of adipose accumulation in relation to erectile dysfunction.

INTRODUCTION: Although previous studies have linked obesity and erectile dysfunction, the novel surrogate indicators of adipose accumulation are more essential and dependable factors to consider. Therefore, the primary objective of the current investigation was to examine and clarify the association between metabolic score for visceral fat (METS-VF) and erectile dysfunction. METHODS: Firstly, multivariate logistic regression analysis, smoothed curve fitting, and threshold effect analysis were employed to investigate the association between METS-VF and erectile dysfunction. Mediation analysis was also performed to evaluate the mediating role of homocysteine and inflammation. After that, subgroup analysis was carried out to examine the stability of the correlation of METS-VF with erectile dysfunction in various population settings. Furthermore, the area under the receiver operating characteristic (ROC) curve and eXtreme Gradient Boosting (XGBoost) algorithm were utilized to assess the capability of identifying METS-VF in comparison to the other four obesity-related indicators in identifying erectile dysfunction. RESULTS: After adjusting for all confounding factors, METS-VF was strongly and favourablely correlated with erectile dysfunction. With each additional unit rise in METS-VF, the prevalence of erectile dysfunction increased by 141%. A J-shaped relationship between METS-VF and erectile dysfunction was discovered through smoothed curve fitting. Marital status, physical activity, and smoking status can potentially modify this association. This finding of the ROC curve suggests that METS-VF had a powerful identifying capacity for erectile dysfunction (AUC = 0.7351). Homocysteine and inflammation mediated 4.24% and 2.81%, respectively. CONCLUSION: The findings of the current investigation suggest that METS-VF can be considered a dependable identifying indicator of erectile dysfunction.

The relationship between oxidative balance score and erectile dysfunction in the U.S. male adult population.

Oxidative stress strongly influences the pathophysiology of erectile dysfunction (ED). In this study, we used the oxidative balance score (OBS), a composite index, to measure the effects of oxidative stress triggered by diet and lifestyle factors. Here, we conducted a cross-sectional study to determine the statistical relationship between OBS and ED among adult males in the U.S. The data from 3318 participants in the National Health and Nutrition Examination Survey (NHANES) 2001-2004 were analyzed. Weighted logistic regression was used to correct for confounding factors and acquire nationwide representative estimates. Generalized additive modeling was used to explore the nonlinear relationship. We also supplemented subgroup and sensitivity analysis to examine the robustness of the main results. Multivariate logistic regression indicated a consistent negative linear association between OBS and ED across all participants [OR (95% CI) = 0.96 (0.94, 0.98)]. After categorizing OBS into tertiles, participants in the highest tertile had 43% lower odds of having ED than those in the lowest tertile [OR (95% CI) = 0.57 (0.37, 0.87)]. The generalized additive model also visualized the linear trend of this association. Furthermore, this linear relationship remained relatively consistent, regardless of whether subgroup or sensitivity analyses were performed. Our findings suggest that adopting a lifestyle and diet pattern that promotes favorable OBS may effectively protect against the development of ED, regardless of the underlying causes.

A novel reuptake inhibitor, IP2015, induces erection by increasing central dopamine and peripheral nitric oxide release.

BACKGROUND AND PURPOSE: An estimated 40% of patients with erectile dysfunction have a poor prognosis for improvement with currently available treatments. The present study investigated whether a newly developed monoamine transport inhibitor, IP2015, improves erectile function. EXPERIMENTAL APPROACH: We investigated the effects of IP2015 on monoamine uptake and binding, erectile function in rats and diabetic mice and the effect on corpus cavernosum contractility. KEY RESULTS: IP2015 inhibited the uptake of 5-HT, noradrenaline and dopamine by human monoamine transporters expressed in cells and in rat brain synaptosomes. Intracavernosal pressure measurement in anaesthetized rats revealed that IP2015 dose-dependently increased the number and the duration of spontaneous erections. Whereas pretreatment with the dopamine D2-like receptor antagonists, clozapine and (-)-sulpiride, or cutting the cavernosal nerve inhibited IP2015-induced erectile responses, the phosphodiesterase type 5 inhibitor sildenafil further enhanced the IP2015-mediated increase in intracavernosal pressure. IP2015 also increased the number of erections in type 2 diabetic db/db mice. Direct intracavernosal injection of IP2015 increased penile pressure, and in corpus cavernosum strips, IP2015 induced concentration-dependent relaxations. These relaxations were enhanced by sildenafil and blunted by endothelial cell removal, a nitric oxide synthase inhibitor, NG-nitro-l-arginine and a D1-like receptor antagonist, SCH23390. Quantitative polymerase chain reaction (qPCR) showed the expression of the dopamine transporter in the rat corpus cavernosum. CONCLUSION AND IMPLICATIONS: Our findings suggest that IP2015 stimulates erectile function by a central mechanism involving dopamine reuptake inhibition and direct NO-mediated relaxation of the erectile tissue. This novel multi-modal mechanism of action could offer a new treatment approach to erectile dysfunction.

BMP4 and GREM1 are targets of SHH signaling and downstream regulators of collagen in the penis.

BACKGROUND: Cavernous nerve (CN) injury, caused by prostatectomy and diabetes, initiates a remodeling process (smooth muscle apoptosis and increased collagen) in the corpora cavernosa of the penis of patients and animal models that is an underlying cause of erectile dysfunction (ED), and the Sonic hedgehog (SHH) pathway plays an essential role in the response of the penis to denervation, as collagen increases with SHH inhibition and decreases with SHH treatment. AIM: We examined if part of the mechanism of how SHH prevents penile remodeling and increased collagen with CN injury involves bone morphogenetic protein 4 (BMP4) and gremlin1 (GREM1) and examined the relationship between SHH, BMP4, GREM1, and collagen in penis of ED patients and rat models of CN injury, SHH inhibition, and SHH, BMP4, and GREM1 treatment. METHODS: Corpora cavernosa of Peyronie's disease (control), prostatectomy, and diabetic ED patients were obtained (N = 30). Adult Sprague Dawley rats (n = 90) underwent (1) CN crush (1-7 days) or sham surgery; (2) CN injury and BMP4, GREM1, or mouse serum albumin (control) treatment via Affi-Gel beads or peptide amphiphile (PA) for 14 days; (3) 5E1 SHH inhibitor, IgG, or phosphate-buffered saline (control) treatment for 2 to 4 days; or (4) CN crush with mouse serum albumin or SHH for 9 days. OUTCOMES: Immunohistochemical and Western analysis for BMP4 and GREM1, and collagen analysis by hydroxyproline and trichrome stain were performed. RESULTS: BMP4 and GREM1 proteins were identified in corpora cavernosa smooth muscle of prostatectomy, diabetic, and Peyronie's patients, and in rat smooth muscle, sympathetic nerve fibers, perineurium, blood vessels, and urethra. Collagen decreased 25.4% in rats with CN injury and BMP4 treatment (P = .02) and increased 61.3% with CN injury and GREM1 treatment (P = .005). Trichrome stain showed increased collagen in rats treated with GREM1. Western analysis identified increased BMP4 and GREM1 in corpora cavernosa of prostatectomy and diabetic patients, and after CN injury (1-2 days) in our rat model. Localization of BMP4 and GREM1 changed with SHH inhibition. SHH treatment increased the monomer form of BMP4 and GREM1, altering their range of signaling. CLINICAL IMPLICATIONS: A better understanding of penile remodeling and how fibrosis occurs with loss of innervation is essential for development of novel ED therapies. STRENGTHS AND LIMITATIONS: The relationship between SHH, BMP4, GREM1, and collagen is complex in the penis. CONCLUSION: BMP4 and GREM1 are downstream targets of SHH that impact collagen and may be useful in collaboration with SHH to prevent penile remodeling and ED.

PKC Inhibition Improves Human Penile Vascular Function and the NO/cGMP Pathway in Diabetic Erectile Dysfunction: The Role of NADPH Oxidase.

Erectile dysfunction (ED) is a frequent and difficult-to-treat condition in diabetic men. Protein kinase C (PKC) is involved in diabetes-related vascular and cavernosal alterations. We aimed to evaluate the role of PKC in endothelial dysfunction and NO/cGMP impairment associated with diabetic ED in the human corpus cavernosum (CC) and penile resistance arteries (PRAs) and the potential mechanisms involved. Functional responses were determined in the CC and PRAs in patients with non-diabetic ED and diabetic ED undergoing penile prosthesis insertion. PKC activator 12,13-phorbol-dibutyrate (PDBu) impaired endothelial relaxations and cGMP generation in response to acetylcholine in the CC from non-diabetic ED. PDBu also impaired responses to a PDE5 inhibitor, sildenafil, in non-diabetic ED patients. Conversely, a PKC inhibitor, GF109203X, improved endothelial, neurogenic, and PDE5-inhibitor-induced relaxations and cGMP generation only in the CC in diabetic ED patients. Endothelial and PDE5-inhibitor-induced vasodilations of PRAs were potentiated only in diabetes. Improvements in endothelial function in diabetes were also achieved with a specific inhibitor of the PKCß2 isoform or an NADPH-oxidase inhibitor, apocynin, which prevented PDBu-induced impairment in non-diabetic patients. PKC inhibition counteracted NO/cGMP impairment and endothelial dysfunction in diabetes-related ED, potentially improving response to PDE5 inhibition.

Semen quality and metabolic profile in people with type 1 diabetes with and without erectile dysfunction: a cross-sectional study.

PURPOSE: The aim of the present study is to evaluate the association of metabolic and glycemic variables with semen parameters in patients with type 1 diabetes (T1D) with and without erectile dysfunction (ED). METHODS: The study population included 88 adults with T1D using a continuous glucose monitoring, of whom 28 with ED (ED group) and 60 without it (NO ED group). All men completed the International Index of Erectile Function (IIEF-5) and underwent body composition analysis (BIA) and semen analysis. RESULTS: ED group showed worse HbA1c levels [median (IQR), 8.4 (7.7, 9.9) vs 7.4 (7, 8.2) %, P < 0.001)], higher insulin dose [60 (51, 65) vs 45 (38, 56) UI/die, P = 0.004)] and a higher total body water and intracellular water as compared with ED group. Men in the ED group presented higher semen volume [2.8 (2.6, 4.2) vs 2.5 (2.2, 2.7) mL, P < 0.001] and sperm concentration [24 (19, 29) vs 20 (12, 23) mil/mL, P = 0.010], but reduced sperm progressive motility [28 (25, 35) vs 35 (25, 36) %, P = 0.011], higher rate of non-progressive motility [15 (10, 15) vs 10 (5, 10) %, P < 0.001] and higher rate of typical morphology [7(5, 8) vs 5 (4, 5) %, P = 0.001]. Based on multivariate logistic regression analysis performed to assess the association between clinical variables and ED, intracellular water (OR 3.829, 95% CI 1.205, 12.163, P = 0.023) resulted as the only independent predictor of ED. CONCLUSION: Men with T1D and ED showed worse metabolic profile which is associated with poor semen quality, as compared with those without ED.

d-Galactose induces the senescence and phenotype switch of corpus cavernosum smooth muscle cells.

Studies regarding age-related erectile dysfunction (ED) based on naturally aging models are limited by their high costs, especially for the acquisition of primary cells from the corpus cavernosum. Herein, d-galactose ( d-gal) was employed to accelerate cell senescence, and the underlying mechanism was explored. As predominant functional cells involved in the erectile response, corpus cavernosum smooth muscle cells (CCSMCs) were isolated from 2-month-old rats. Following this, d-gal was introduced to induce cell senescence, which was verified via ß-galactosidase staining. The effects of d-gal on CCSMCs were evaluated by terminal deoxynucleoitidyl transferase dUTP nick-end labeling (TUNEL), immunofluorescence staining, flow cytometry, western blot, and quantitative real-time polymerase chain reaction (qRT-PCR). Furthermore, RNA interference (RNAi) was carried out for rescue experiments. Subsequently, the influence of senescence on the corpus cavernosum was determined via scanning electron microscopy, qRT-PCR, immunohistochemistry, TUNEL, and Masson stainings. The results revealed that the accelerated senescence of CCSMCs was promoted by d-gal. Simultaneously, smooth muscle alpha-actin (alpha-SMA) expression was inhibited, while that of osteopontin (OPN) and Krüppel-like factor 4 (KLF4), as well as fibrotic and apoptotic levels, were elevated. After knocking down KLF4 expression in d-gal-induced CCSMCs by RNAi, the expression level of cellular alpha-SMA increased. Contrastingly, the OPN expression, apoptotic and fibrotic levels declined. In addition, cellular senescence acquired partial remission. Accordingly, in the aged corpus cavernosum, the fibrotic and apoptotic rates were increased, followed by downregulation in the expression of alpha-SMA and the concurrent upregulation in the expression of OPN and KLF4. Overall, our results signaled that d-gal-induced accelerated senescence of CCSMCs could trigger fibrosis, apoptosis and phenotypic switch to the synthetic state, potentially attributed to the upregulation of KLF4 expression, which may be a multipotential therapeutic target of age-related ED.

BMP2 restores erectile dysfunction through neurovascular regeneration and fibrosis reduction in diabetic mice.

BACKGROUND: The odds of erectile dysfunction are three times more prevalent in diabetes. Severe peripheral vascular and neural damage in diabetic patients responds poorly to phosphodiesterase-5 (PDE5) inhibitors. However, bone morphogenetic protein 2 is known to be involved in angiogenesis. OBJECTIVES: To assess the efficacy of bone morphogenetic protein 2 in stimulating angiogenesis and augmenting nerve regeneration in a mouse model of diabetic-induced erectile dysfunction. MATERIALS AND METHODS: The induction of diabetes mellitus was performed by streptozotocin (50 mg/kg daily) administered intraperitoneally for 5 successive days to male C57BL/6 mice that were 8 weeks old. Eight weeks post-inductions, animals were allocated to one of five groups: a control group, a streptozotocin-induced diabetic mouse group receiving two intracavernous 20 µL phosphate-buffered saline injections, or one of three bone morphogenetic protein 2 groups administered two injections of bone morphogenetic protein 2 protein (1, 5, or 10 µg) diluted in 20 µL of phosphate-buffered saline within a 3-day interval between the first and second injections. The erectile functions were assessed 2 weeks after phosphate-buffered saline or bone morphogenetic protein 2 protein injections by recording the intracavernous pressure through cavernous nerve electrical stimulation. Angiogenic activities and nerve regenerating effects of bone morphogenetic protein 2 were determined in penile tissues, aorta, vena cava, the main pelvic ganglions, the dorsal roots, and from the primary cultured mouse cavernous endothelial cells. Moreover, fibrosis-related factor protein expressions were evaluated by western blotting. RESULTS: Erectile function recovery to 81% of the control value in diabetic mice was found with intracavernous bone morphogenetic protein 2 injection (5 µg/20 µL). Pericytes and endothelial cells were extensively restored. It was confirmed that angiogenesis was promoted in the corpus cavernosum of diabetic mice treated with bone morphogenetic protein 2 through increased ex vivo sprouting of aortic rings, vena cava and penile tissues, and migration and tube formation of mouse cavernous endothelial cells. Bone morphogenetic protein 2 protein enhanced cell proliferation and reduced apoptosis in mouse cavernous endothelial cells and penile tissues, and promoted neurite outgrowth in major pelvic ganglia and dorsal root ganglia under high-glucose conditions. Furthermore, bone morphogenetic protein 2 suppressed fibrosis by reducing mouse cavernous endothelial cell fibronectin, collagen 1, and collagen 4 levels under high-glucose conditions. CONCLUSION: Bone morphogenetic protein 2 modulates neurovascular regeneration and inhibits fibrosis to revive the mouse erection function in diabetic conditions. Our findings propose that the bone morphogenetic protein 2 protein represents a novel and promising approach to treating diabetes-related erectile dysfunction.

Biodegradable nano black phosphorus based SDF1-α delivery system ameliorates Erectile Dysfunction in a cavernous nerve injury rat model by recruiting endogenous stem/progenitor cells.

Stem cell (SC) therapy has been shown high prospects in erectile dysfunction (ED) treatment. Without ethical issues and risks of immune rejection and tumorigenesis of exogenous SC therapy, endogenous stem/progenitor cells (S/PCs) have a better potential for ED management, and their homing and redistribution are controlled by SDF1-α/CXCR4 axis. Considering black phosphorus nanosheet (BPNS) has emerged as an efficient and safe drug vehicle due to its large surface area, biodegradability, and the ability to retain and slowly release its loaded drugs, BPNS is utilized to load SDF1-α, a chemokine for S/PCs, to construct the BP@SDF1-α complex to efficiently recruit stem cells (SCs) by injury-site injection and thus ameliorate ED within the bilateral cavernous nerve injury (BCNI) rat models. We find that BP@SDF1-α can efficiently recruit exogenous SCs and endogenous S/PCs to corpus cavernosum and main pelvic ganglion (MPG) by local administration. Of note, ascribing to endogenous S/PCs recruitment, it also successfully alleviates ED in BCNI rat models by enhancing the protein expression levels of α-SMA, CD31, and nNOs, and eliciting less collagen deposition in the penis after its combined injection at corpus cavernosum and MPG. Thus, this study provides a new insight into the treatment of ED with endogenous S/PCs. BIODEGRADABLE NANO BLACK PHOSPHORUS BASED SDF1-α DELIVERY SYSTEM AMELIORATES ERECTILE DYSFUNCTION IN A CAVERNOUS NERVE INJURY RAT MODEL BY RECRUITING ENDOGENOUS STEM/PROGENITOR CELLS.

Effects of transplantation of umbilical cord blood mononuclear cells into the scrotum on sexual function in elderly mice.

Aim: This study investigated the effect of allografting umbilical cord blood mononuclear cells (UCBMCs) into the scrotum on sexual function in male elderly mice. Methods: UCBMCs were injected once into the scrotal sheath cavity of elderly mice. Results: The transplanted UCBMCs survived in the scrotal sheath cavity for 1 month. The mice had significantly increased blood testosterone concentrations, cyclic guanosine monophosphate (cGMP) levels and total nitric oxide synthase (T-NOS) activity in the corpus cavernosum and an increase in the number of mouse matings within 30 min (all p = 0.000). Conclusion: Scrotum-implanted UCBMCs improve the sexual function of male elderly mice through testosterone production and the NOS/cGMP pathway, which may provide an innovative transplantation approach for the treatment of erectile dysfunction.