Dual Strategy with Adipose-Derived Stem Cells and l-arginine Recovered Cavernosal Functions in a Rat Model of Radical Prostatectomy.

As standard therapy for prostate cancer, radical prostatectomy causes cavernous nerve (CN) injury and increases fibrosis and hypoxia-induced penile structural alterations. This study aimed to determine the potential beneficial effects of adipose-derived stem cells (ADSCs) and l-arginine alone or in combination on the penile erection in a rat model of erectile dysfunction caused by bilateral cavernous nerve transection (CNT). Male rats (n = 35) were randomized into five groups: Sham-operated; CNT (4-weeks); CNT plus ADSCs (1 × 106 cells by intracavernosal injection); CNT plus l-arginine (4 weeks, 10 mg/kg/day, oral); and ADSCs combined with l-arginine in CNT. In vivo erectile responses and in vitro relaxant responses were measured. Western blot and immunohistochemistry analyses were used to determine the expression and localization of endothelial nitric oxide synthase, neuronal nitric oxide synthase, transforming growth factor-beta 1, hypoxia-inducible factor-1 alpha (HIF-1α), and apoptosis markers (Bax and Bcl-2). The ratio of smooth muscle to collagen and nerve regeneration were calculated using Masson's trichrome and nicotinamide adenine dinucleotide phosphate (NADPH)-diaphorase staining. The combined treatment restored diminished erectile responses, endothelium-dependent acetylcholine, and electrical field stimulation-induced relaxation of the corpus cavernosum in rats with CNT, whereas either monotherapy produced only partial improvements. All treatment regimens restored increases in the protein expression of HIF-1 and Bax in rats with CNT. The decrease in smooth muscle mass and NADPH-diaphorase-positive nerve fibers was partially ameliorated by monotherapy, whereas combined therapy led to recovery. These findings indicate that combined treatment with ADSCs and l-arginine may restore erectile function in rats with CNT by inhibiting hypoxia-induced neurotoxicity and preserving endothelium function and smooth muscle content.

Combined levothyroxine and testosterone treatment for restoring erectile dysfunction in propylthiouracil-induced hypothyroid rats.

BACKGROUND: Sexual dysfunction may indicate severe endocrine diseases. Recent research has suggested a link between hypothyroidism, low testosterone (T) levels, and erectile dysfunction (ED); however, the exact cause is unknown. AIM: We sought to investigate possible beneficial effects of levothyroxine and T alone or in combination on ED in propylthiouracil (PTU)-induced hypothyroid rats. METHODS: Adult Wistar rats (n = 35) were divided into 5 groups: control, PTU-induced hypothyroidism, PTU + levothyroxine, PTU + Sustanon (a mixture of 4 types of T: propionate, phenylpropionate, isocaproate, and decanoate) and PTU + levothyroxine + Sustanon. PTU was given in drinking water for 6 weeks. Four weeks after PTU administration, levothyroxine (20 µg microgram kg/day, oral) and Sustanon (10 mg/kg/week, intramuscular) were given for 2 weeks. Serum levels of total T, triiodothyronine (T3), and thyroxine (T4) were determined. In vivo erectile response and in vitro relaxant responses were measured. Localization of neuronal nitric oxide synthase (nNOS), endothelial NOS (eNOS), and phosphodiesterase type 5 (PDE5) were determined using immunohistochemical analysis. The relative area of smooth muscle to collagen was measured using Masson trichrome staining. OUTCOMES: Outcome variables included in vivo erectile function, in vitro relaxant and contractile responses of corpus cavernosum (CC) strips; protein localization of eNOS, nNOS, and PDE5; and smooth muscle content in penile tissue. RESULTS: The rat model of hypothyroidism showed a significant decline in serum levels of total T, T3, and T4. Levothyroxine increased T3 and T4 levels, whereas Sustanon normalized only total T levels. Combined treatment enhanced all hormone levels. Rats with hypothyroidism displayed the lowest erectile response (P < 0.001 vs controls). Combined treatment returned reduced responses, while partial amelioration was observed after levothyroxine and Sustanon treatment alone. Acetylcholine (P < 0.01 vs controls), electrical field stimulation (P < 0.001 vs controls), and sildenafil-induced relaxant responses (P < 0.05 vs controls) were decreased in the CC strips from hypothyroid rats. The combined treatment increased the reduction in relaxation responses. Levothyroxine and Sustanon restored decreases in eNOS and nNOS expression in the hypothyroid group. There was no significant difference in PDE5 expression among groups. Monotreatment partially enhanced reduced smooth muscle mass, while combined therapy completely recovered. CLINICAL IMPLICATIONS: The combination of thyroid hormones and T is likely to be a therapeutic approach for treatment of hypothyroidism-induced ED in men. STRENGTHS AND LIMITATIONS: Beneficial effects of levothyroxine and Sustanon treatment were shown in vitro and in vivo in PTU-induced hypothyroid rats. The main limitation of the study was the lack of measurement of androgen-sensitive organ weights and luteinizing hormone, follicle-stimulating hormone, and prolactin levels. CONCLUSION: These findings demonstrate that neurogenic and endothelium-dependent relaxation responses are reduced by hypothyroidism, which is detrimental to T levels and erectile responses. Levothyroxine and Sustanon combination medication was able to counteract this effect.

Co-administration of sodium hydrosulfide and tadalafil modulates hypoxia and oxidative stress on bladder dysfunction in a rat model of bladder outlet obstruction

ABSTRACT Purpose: This study aimed to assess the possible healing effect of combination treatment with a hydrogen sulfide (H2S) donor, sodium hydrosulfide (NaHS) plus tadalafil on partial bladder outlet obstruction (PBOO)-induced bladder dysfunction. Materials and Methods: A total of 75 male Sprague-Dawley rats aged 10-wk and 300-350g were divided into five groups; control; PBOO; PBOO+NaHS (5.6mg/kg/day, i.p., 6-wk); PBOO+tadalafil (2mg/kg/day, oral, 6-wk) and PBOO+NaHS+tadalafil. PBOO was created by partial urethral ligation. 6 weeks after obstruction, the in vitro contractile responses of the detrusor muscle and Western blotting, H2S and malondialdehyde assay were performed in bladder tissues. Results: There was an increase in bladder weight(p<0.001) and a decrease in contractile responses to KCl (p<0.001), carbachol (p<0.01), electrical field stimulation (p<0.05) and ATP (p<0.001) in the detrusor smooth muscle of obstructed rats which was normalized after the combination treatment. Cystathionine γ-lyase and cystathionine β-synthase, and nuclear factor kappa B protein levels did not significantly differ among groups. The obstruction induced decrement in 3-mercaptopyruvate sulfur transferase protein expression(p<0.001) and H2S levels(p<0.01) as well as increment in protein expressions of neuronal nitric oxide synthase (NO, p<0.001), endothelial NOS (p<0.05), inducible NOS(p<0.001), hypoxia-inducible factor 1-alpha (p<0.01), and malondialdehyde levels (p<0.01), when combined treatment entirely normalized. Conclusions: Combination therapy has beneficial effects on bladder dysfunction via regulating both H2S and nitric oxide pathways as well as downregulation of oxidative stress and hypoxia. The synergistic effect of H2S and nitric oxide is likely to modulate bladder function, which supports the combined therapy for enhancing clinical outcomes in men with BPH/LUTS.

Cytotoxic and Apoptotic Effects of the Combination of Borax (Sodium Tetraborate) and 5-Fluorouracil on DLD-1 Human Colorectal Adenocarcinoma Cell Line.

Objectives: Colorectal cancer (CRC) remains a crucial health problem due to the toxicity of 5-Fluorouracil (5-FU) as first-line chemotherapy agent for treating CRC. The anticancer effects of boron and its compounds have been shown in various cell lines. This study aimed to examine the cytotoxic and apoptotic effects of borax (sodium tetraborate) alone or along with 5-FU on human CRC cells, DLD-1. Materials and Methods: Cytotoxicity and apoptosis were determined by 3-(4,5-dimethylthiazolyl-2)-2,5-diphenyltetrazolium bromide (MTT) assay, 4',6-diamidino-2-phenylindole and annexin V/propidium iodide staining. Results: The results showed that combined treatment revealed a significant time- and concentration-dependent cytotoxic effect on DLD-1 cells compared with borax or 5-FU treatment alone. The combination of borax and 5-FU induced a clear increase in the early apoptotic cell percentage, compared to the cells treated with monotherapies. Additionally, a significant increase in condensed and fragmented nuclei was detected in DLD-1 cells treated with the combination treatment compared with borax or 5-FU alone. Conclusion: Our current findings suggest that the combination of borax with 5-FU has a strong cytotoxic and apoptotic effect on the human CRC DLD-1 cells.

Co-administration of sodium hydrosulfide and tadalafil modulates hypoxia and oxidative stress on bladder dysfunction in a rat model of bladder outlet obstruction.

PURPOSE: This study aimed to assess the possible healing effect of combination treatment with a hydrogen sulfide (H2S) donor, sodium hydrosulfide (NaHS) plus tadalafil on partial bladder outlet obstruction (PBOO)-induced bladder dysfunction. MATERIALS AND METHODS: A total of 75 male Sprague-Dawley rats aged 10-wk and 300-350g were divided into five groups; control; PBOO; PBOO+NaHS (5.6mg/kg/day, i.p., 6-wk); PBOO+tadalafil (2mg/kg/day, oral, 6-wk) and PBOO+NaHS+tadalafil. PBOO was created by partial urethral ligation. 6 weeks after obstruction, the in vitro contractile responses of the detrusor muscle and Western blotting, H2S and malondialdehyde assay were performed in bladder tissues. RESULTS: There was an increase in bladder weight(p<0.001) and a decrease in contractile responses to KCL(p<0.001), carbachol(p<0.01), electrical field stimulation(p<0.05) and ATP (p<0.001) in the detrusor smooth muscle of obstructed rats which was normalized after the combination treatment. Cystathionine γ-lyase and cystathionine ß-synthase, and nuclear factor kappa B protein levels did not significantly differ among groups. The obstruction induced decrement in 3-mercaptopyruvate sulfur transferase protein expression(p<0.001) and H2S levels(p<0.01) as well as increment in protein expressions of neuronal nitric oxide synthase (NO, p<0.001), endothelial NOS (p<0.05), inducible NOS(p<0.001), hypoxia-inducible factor 1-alpha (p<0.01), and malondialdehyde levels (p<0.01), when combined treatment entirely normalized. CONCLUSIONS: Combination therapy has beneficial effects on bladder dysfunction via regulating both H2S and nitric oxide pathways as well as downregulation of oxidative stress and hypoxia. The synergistic effect of H2S and nitric oxide is likely to modulate bladder function, which supports the combined therapy for enhancing clinical outcomes in men with BPH/LUTS.

Impact of COVID-19 on male urogenital health: Success of vaccines.

Throughout 2021, the scientific and medical communities were concentrated on dealing with the acute morbidity and mortality induced by the COVID-19 pandemic due to the severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2). We reviewed the present data for adverse effects of COVID-19 on the different parts of the male urogenital system during the dynamic situation of the COVID-19 pandemic. With the approval of COVID-19 vaccinations, there is a ray of hope at the end of this dark tunnel and a chance to look ahead for the management of long-term consequences in males with urogenital illness. A multidisciplinary investigation of these cases could provide information for establishing and optimizing treatment protocols.

Sodium butyrate ameliorates erectile dysfunction through fibrosis in a rat model of partial bladder outlet obstruction.

BACKGROUND: In different animal models, a histone deacetylase (HDAC) inhibitor, sodium butyrate (NaBu) reduced inflammation, oxidative stress and fibrosis which were involved in the pathogenesis of erectile dysfunction (ED), but whether NaBu could improve ED in an experimental animal model of benign prostate hyperplasia (BPH) was not known. OBJECTIVE: To investigate the preventive effect of NaBu on ED in a partial bladder outlet obstruction (PBOO) rat model. MATERIALS AND METHODS: PBOO was induced by partial urethral obstruction. NaBu (20 mg/kg/day) was administered orally to rats for 6 weeks after creation of PBOO. In vivo erectile responses, in vitro relaxation and contraction responses in cavernosal tissue were measured. Real-time polymerase chain reaction (RT-PCR) and Western blot were performed to determine the gene and protein expression. Inflammation, fibrosis, and localization of proteins were evaluated using histological techniques. HDAC activity and tumor necrosis factor (TNF)-α levels were measured in penile tissues. RESULTS: NaBu improved decreased intracavernosal pressure/mean arterial pressure, nitrergic and endothelium-dependent relaxation responses, and contractile responses to phenylephrine and electrical field stimulation in the PBOO group without affecting increased bladder weight. Increased endothelial nitric oxide synthase (eNOS), transforming growth factor (TGF)-ß1, and nuclear factor kappa B (NF-κB) gene levels in PBOO group were ameliorated by NaBu treatment. The administration of NaBu to PBOO rats significantly increased neuronal NOS (nNOS) and decreased TGF-ß1 protein expression. The nuclear/cytosolic ratio of NF-κB demonstrated a decrease in PBOO and all treatment groups compared to control. A significant increase in the nuclear-to-cytoplasmic ratio of nuclear factor erythroid 2-related factor 2 (Nrf2) after PBOO was reduced by the treatment. Both eNOS and inducible NOS (iNOS) protein expression, together with TNF-α levels did not differ in the penile tissue of all groups. In histological analysis, increased TGF-ß1 protein expression and fibrosis, as well as decreased nNOS protein in PBOO, were reversed by the treatment. NaBu did not normalize moderate inflammation in obstructed rats. An increase in the HDAC activity in PBOO was significantly suppressed by NaBu. DISCUSSION: Inhibition of the HDAC activity by NaBu in penile tissue could ameliorate fibrosis-associated changes induced by PBOO. CONCLUSION: NaBu promotes recovery of erectile function, and also significantly prevents penile fibrosis and normalizes TGF-ß1 and nNOS protein expression in a rat model of PBOO. The HDAC pathway may present a promising target to prevent ED in patients with BPH.

An update on the current status and future prospects of erectile dysfunction following radical prostatectomy.

BACKGROUND: Radical prostatectomy (RP) and radiation treatment are standard options for localized prostate cancer. Even though nerve-sparing techniques have been increasingly utilized in RP, erectile dysfunction (ED) due to neuropraxia remains a frequent complication. Erectile function recovery rates after RP remain unsatisfactory, and many men still suffer despite the availability of various therapies. OBJECTIVE: This systematic review aims to summarize the current treatments for post-RP-ED, assess the underlying pathological mechanisms, and emphasize promising therapeutic strategies based on the evidence from basic research. METHOD: Evaluation and review of articles on the relevant topic published between 2010 and 2021, which are indexed and listed in the PubMed database. RESULTS: Phosphodiesterase type 5 inhibitors, intracavernosal and intraurethral injections, vacuum erection devices, pelvic muscle training, and surgical procedures are utilized for penile rehabilitation. Clinical trials evaluating the efficacy of erectogenic drugs in this setting are conflicting and far from being conclusive. The use of androgen deprivation therapy in certain scenarios after RP further exacerbates the already problematic situation and emphasizes the need for effective treatment strategies. CONCLUSION: This article is a detailed overview focusing on the pathophysiology and mechanism of the nerve injury developed during RP and a compilation of various strategies to induce cavernous nerve regeneration to improve erectile function (EF). These strategies include stem cell therapy, gene therapy, growth factors, low-intensity extracorporeal shockwave therapy, immunophilins, and various pharmacological approaches that have induced improvements in EF in experimental models of cavernous nerve injury. Many of the mentioned strategies can improve EF following RP if transformed into clinically applicable safe, and effective techniques with reproducible outcomes.

Analysis of Changes in Serum Levels and Gene Expression Profiles of Novel Adipocytokines (Omentin, Vaspin, Irisin and Visfatin) and Their Correlation with Serum C-reactive Protein Levels in Women Diagnosed with Endometriosis

Objectives: This study aimed to investigate the role of new adipocytokines (omentin, vaspin, irisin and visfatin) in the development of endometriosis and the relationship of these adipocytokines with the inflammatory marker, C-reactive protein (CRP) levels in serum. Materials and Methods: In this study, endometriosis (n=16) and control groups (n=14) were determined via ultrasound. Serum omentin, vaspin and irisin levels were measured by ELISA method. CRP levels in serum and the gene expression of visfatin and vaspin in whole blood samples were determined by clinical analyzer and the real-time polymerase chain reaction, respectively. Results: Serum irisin and CRP levels in the endometriosis group were significantly higher than in the control group. Irisin protein levels demonstrated a positive correlation with body mass index and CRP in women diagnosed with endometriosis. No statistically significant difference was found in serum omentin and vaspin levels between groups. The visfatin and vaspin gene expression in whole blood samples from the endometriosis group was found to be significantly lower than the control group. Conclusion: Increased levels of serum irisin and decreased visfatin and vaspin gene expressions in blood may be considered as a potential biomarker in endometriosis. The identification of new adipocytokines, which demonstrate an alteration in the presence of endometriosis and the relationship between these adipocytokines and inflammation will facilitate the detection of mechanisms involved in endometriosis and will lead to the development of targeted therapy.

Restorative effects of red onion (Allium cepa L.) juice on erectile function after-treatment with 5α-reductase inhibitor in rats.

Benign prostatic hyperplasia (BPH) is one of the most prevalent conditions among aged men. The use of 5α-reductase inhibitors (5-ARIs) to treat BPH was linked to erectile dysfunction (ED). Many medicinal plants and secondary metabolites are used in the management of ED. Onion (Allium cepa L.) is an economically affordable vegetable with vital phytochemicals and biological functions. The study aimed to identify the beneficial effects of onion juice on dutasteride (a 5-ARI)-induced ED. Rats were divided into two groups (n = 5 per group): control and dutasteride-treated rats (0.5 mg/kg/day). Dutasteride was administered in drinking water for 12 weeks. Experiments were performed at the end of the 12th week. In vivo erectile responses were measured before and after intracavernosal injection of onion. Relaxant responses to onion juice were examined in the corpus cavernosum (CC). Acetylcholine (ACh)-, electrical field stimulation (EFS)-, sodium nitroprusside (SNP)-induced relaxation responses in CC tissues were evaluated in the absence and presence of onion juice. Total intracavernosal pressure (ICP) and ICP/ mean arterial pressure were significantly reduced in dutasteride-treated rats (1881.14 ± 249.72 mmHg, P < 0.001;0.26 ± 0.03, P < 0.01) as compared to control rats (4542.60 ± 429.19 mmHg, 0.51 ± 0.05), which was normalized after the intracavernous administration of onion (3288.60 ± 185.45 mmHg, 0.58 ± 0.04). Onion markedly induced relaxant responses in control (72.5 ± 4.7) and dutasteride-treated (66.5 ± 2.7) groups after precontraction with phenylephrine. Relaxation responses to onion were partially inhibited after precontraction with KCl (32.5 ± 3.1, P < 0.001). The relaxant responses to ACh (14.9 ± 4.2, P < 0.01) were diminished in dutasteride-treated CC) compared to control CC (59.8 ± 3.4), which was enhanced after the incubation with onion (36.6 ± 4.8). There were no differences in relaxation response to SNP among all groups. However, relaxation response to SNP was reduced in dutasteride-treated CC at 1 µM (P < 0.05) and 10 µM dosages (P < 0.001), which was partially increased after the incubation with onion at 10 µM dosage (P < 0.01). The presence of onion did not change the reduction in EFS-caused relaxation in the dutasteride-treated group. The current data suggest that red onion juice has a restorative effect on erectile function and endothelium-dependent relaxation response following the treatment of dutasteride.

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.

Mirabegron, A Selective ß3-Adrenoceptor Agonist Causes an Improvement in Erectile Dysfunction in Diabetic Rats.

AIM: To investigate the possible beneficial effect of mirabegron [a selective ß3-adrenoceptor (AR) agonist] treatment on erectile dysfunction (ED) in streptozotocin-induced diabetic rats. METHODS: Sprague-Dawley rats (n=20) were divided into two groups: control group and streptozotocin-induced diabetic group. In vivo erectile responses were evaluated after intracavernosal injection of mirabegron (0.4 mg/kg) in rats. The relaxation responses to electrical field stimulation (EFS, 10 Hz), sodium nitroprusside (SNP, 10 nM) and sildenafil (1 µM) of corpus cavernosum (CC) strips were examined after the incubation with mirabegron (10 µM). ß3-ARs expression and localization were determined by Western blot and immunohistochemical analyses in CC tissue. RESULTS: In vivo erectile responses of diabetic rats [intracavernasal pressure (ICP) / mean arterial pressure, 0.17±0.01] were decreased, which were restored after administration of mirabegron (0.75±0.01, P<0.001). The basal ICP (7.1±0.6 mmHg) in diabetic rats was markedly increased after mirabegron (36.1 ±5.4 mmHg, P<0.01). Mirabegron caused markedly relaxation in diabetic rat CC after phenylephrine precontraction. The relaxation responses to EFS and sildenafil were reduced in diabetic CC, which were increased in the presence of mirabegron. Mirabegron enhanced SNP-induced relaxation response in both groups. The expression and immunoreactivity of ß3-ARs localized to CC smooth muscle were observed in control and diabetic rats. CONCLUSIONS: This is the first study to show that intracavernosal administration of mirabegron improved erectile function and neurogenic relaxation of CC in diabetic rats. These results may be supported by further studies using combinations of mirabegron and phosphodiesterase type 5 (PDE5) inhibitors for the treatment of diabetic ED, especially in patients who do not respond to PDE5 inhibitor therapy.

Testosterone positively regulates functional responses and nitric oxide expression in the isolated human corpus cavernosum.

BACKGROUND: Testosterone (T) deficiency is associated with erectile dysfunction (ED). The relaxant response of T on the corporal smooth muscle through a non-genomic pathway has been reported; however, the in vitro modulating effects of T on human corpus cavernosum (HCC) have not been studied. OBJECTIVES: To compare the effects of various concentrations of T on nitric oxide (NO)-dependent and nitric oxide-independent relaxation in organ bath studies and elucidate its mode of action, specifically targeting the cavernous NO/cyclic guanosine monophosphate (cGMP) pathway. MATERIALS AND METHODS: Human corpus cavernosum (HCC) samples were obtained from men undergoing penile prosthesis implantation (n = 9). After phenylephrine (Phe) precontraction, the effects of various relaxant drugs of HCC strips were performed using organ bath at low (150 ng/dL), eugonadal (400 ng/dL), and hypergonadal (600 ng/dL) T concentrations. The penile tissue measurements of endothelial nitric oxide synthase (eNOS), neuronal (n)NOS, and phosphodiesterase type 5 (PDE5) were evaluated via immunostaining, Western blot, cGMP and nitrite/nitrate (NOx) assays. RESULTS: Relaxation responses to ACh and EFS in isolated HCC strips were significantly increased at all T levels compared with untreated tissues. The sildenafil-induced relaxant response was significantly increased at both eugonadal and hypergonadal T levels. Normal and high levels of T are accompanied by increased eNOS, nNOS, cGMP, and NOx levels, along with reduced PDE5 protein expression. CONCLUSION: This study reveals an important role of short-term and modulatory effects of different concentrations of T in HCC. T positively regulates functional activities, inhibition of PDE5 expression, and formation of cGMP and NOx in HCC. These results demonstrate that T indirectly contributes to HCC relaxation via downstream effects on nNOS, eNOS, and cGMP and by inhibiting PDE5. This action provides a rationale for normalizing T levels in hypogonadal men with ED, especially when PDE5 inhibitors are ineffective. T replacement therapy may improve erectile function by modulating endothelial function in hypogonadal men.

The beneficial effect of clove essential oil and its major component, eugenol, on erectile function in diabetic rats.

Diabetic men are at a higher risk of erectile dysfunction (ED). A tropical plant, clove (Syn. Eugenia caryophyllata, Caryophyllus aromaticus L., Syzygium aromaticum (L.) Merr. & L.M. Perry) from the Myrtaceae family has displayed aphrodisiac activity. The present research aimed to investigate the impacts of clove essential oil (CEO) and the ingredient of CEO, eugenol (E) on ED in diabetic rats. We divided Sprague-Dawley rats into control and diabetic groups. Erectile function was evaluated before and after CEO and E intracavernosal injection. CEO- and E-induced relaxation responses were investigated in isolated corpus cavernosum (CC) using various inhibitors. The intracavernous administration of CEO and E restored erectile responses in diabetic rats. CEO and E induced remarkable relaxation in all groups. CEO- and E-induced relaxation responses were partially inhibited after pre-contraction with KCl. Tetraethylammonium and glibenclamide inhibited the relaxation response to CEO. Glibenclamide inhibited maximum relaxation to E. The inhibitors of nitric oxide synthase (NOS), soluble guanylyl cyclase and nifedipine did not change CEO- and E-induced relaxation responses. The current results suggest that CEO and the major compound of the essential oil, E improved diabetes-induced ED in rats, and CEO caused CC relaxation via K+ channels independently NO signalling pathway.

The Inflammation Network in the Pathogenesis of Erectile Dysfunction: Attractive Potential Therapeutic Targets.

BACKGROUND: Erectile dysfunction (ED) is an evolving health problem in the aging male population. Chronic low-grade inflammation is a critical component of ED pathogenesis and a probable intermediate stage of endothelial dysfunction, especially in metabolic diseases, with the inclusion of obesity, metabolic syndrome, and diabetes. OBJECTIVE: This review will present an overview of preclinical and clinical data regarding common inflammatory mechanisms involved in the pathogenesis of ED associated with metabolic diseases and the effect of antiinflammatory drugs on ED. METHODS: A literature search of existing pre-clinical and clinical studies was performed on databases [Pubmed (MEDLINE), Scopus, and Embase] from January 2000 to October 2019. RESULTS: Low-grade inflammation is a possible pathological role in endothelial dysfunction as a consequence of ED and other related metabolic diseases. Increased inflammation and endothelial/prothrombotic markers can be associated with the presence and degree of ED. Pharmacological therapy and modification of lifestyle and risk factors may have a significant role in the recovery of erectile response through reduction of inflammatory marker levels. CONCLUSION: Inflammation is the least common denominator in the pathology of ED and metabolic disorders. The inflammatory process of ED includes a shift in the complex interactions of cytokines, chemokines, and adhesion molecules. These data have established that anti-inflammatory agents could be used as a therapeutic opportunity in the prevention and treatment of ED. Further research on inflammation-related mechanisms underlying ED and the effect of therapeutic strategies aimed at reducing inflammation is required for a better understanding of the pathogenesis and successful management of ED.

The Effects of Androgens on Cardiometabolic Syndrome: Current Therapeutic Concepts.

INTRODUCTION: Cardiometabolic syndrome (CMS), as a bunch of metabolic disorders mainly characterized by type 2 diabetes mellitus (T2DM), hypertension, atherosclerosis, central adiposity, and abdominal obesity triggering androgen deficiency, is one of the most critical threats to men. Although many significant preclinical and clinical findings explain CMS, new approaches toward common pathophysiological mechanisms and reasonable therapeutic targets are lacking. AIM: To gain a further understanding of the role of androgen levels in various facets of CMS such as the constellation of cardiometabolic risk factors including central adiposity, dyslipidemia, insulin resistance, diabetes, and arterial hypertension and to define future directions for development of effective therapeutic modalities. METHODS: Clinical and experimental data were searched through scientific literature databases (PubMed) from 2009 to October 2019. MAIN OUTCOME MEASURE: Evidence from basic and clinical research was gathered with regard to the causal impact and therapeutic roles of androgens on CMS. RESULTS: There are important mechanisms implicated in androgen levels and the risk of CMS. Low testosterone levels have many signs and symptoms on cardiometabolic and glycometabolic risks as well as abdominal obesity in men. CLINICAL IMPLICATIONS: The implications of the findings can shed light on future improvements in androgen levels and add potentially predictive risk for CMS, as well as T2DM, abdominal obesity to guide clinical management in the early stage. STRENGTHS & LIMITATIONS: This comprehensive review refers to the association between androgens and cardiovascular health. A limitation of this study is the lack of large, prospective population-based studies that analyze the effects of testosterone treatment on CMS or mortality. CONCLUSION: Low testosterone levels have several common features with metabolic syndrome. Thus, testosterone may have preventive role in the progress of metabolic syndrome and subsequent T2DM, abdominal obesity, and cardiovascular disease and likely affect aging men's health mainly through endocrine and vascular mechanisms. Further studies are necessary to evaluate the therapeutic interventions directed at preventing CMS in men. Kirlangic OF, Yilmaz-Oral D, Kaya-Sezginer E, et al. The Effects of Androgens on Cardiometabolic Syndrome: Current Therapeutic Concepts. Sex Med 2020;8:132-155.

Evaluation of combined therapeutic effects of hydrogen sulfide donor sodium hydrogen sulfide and phosphodiesterase type-5 inhibitor tadalafil on erectile dysfunction in a partially bladder outlet obstructed rat model.

AIMS: To evaluate the impacts of hydrogen sulfide (H2 S) donor, sodium hydrogen sulfide (NaHS), and phosphodiesterase type-5 inhibitor (PDE5i), tadalafil per se and their combination treatment on partial bladder outlet obstruction (PBOO)-induced erectile dysfunction (ED). METHODS: Sprague-Dawley rats were equally divided into five groups: (a) sham-operated control; (b) PBOO; (c) PBOO-treated with NaHS (5.6 mg/kg/day, ip); (d) PBOO-treated with tadalafil (2 mg/kg/day, oral); and (e) PBOO-treated with combination of NaHS and tadalafil. The obstruction was created by urethral ligation for 6 weeks. In vivo erectile responses, in vitro relaxant and contractile responses in penile tissue as well as protein expression of nitric oxide synthases (NOS), H2 S synthesis enzymes, oxidative stress, hypoxia, fibrosis markers, and the smooth muscle/collagen ratio and apoptosis were analyzed. RESULTS: Combined treatment entirely returned increased bladder mass, reduced erectile responses, relaxation responses to acetylcholine, and electrical field stimulation in obstructed rats, while partial amelioration was observed after mono-treatment. Decreased neuronal NOS and 3-mercaptopiruvate transferase enzyme expressions in penile tissue from obstructed rats were also entirely restored by the combined treatment. Mono-treatment partially improved increased hypoxia, oxidative stress, fibrosis markers, decreased smooth muscle mass, and H2 S levels, while combined therapy completely recovered. CONCLUSIONS: The combination therapy with H2 S donor and PDE5i had positive effects on erectile responses through the improvement of ischemia-induced morphological and functional penile alterations in obstruction. H2 S and NO may likely play a synergistic role in the regulation of erectile function and have constructive effects on clinical outcomes in male patients with ED and benign prostatic hyperplasia/lower urinary tract symptoms.

Harnessing Stem Cell Potential for the Treatment of Erectile Function in Men with Diabetes Mellitus: From Preclinical/Clinical Perspectives to Penile Tissue Engineering.

BACKGROUND: According to the World Health Organization, more than 150 million people are diabetic, and this number will increase twofold by the year 2025. Diabetes-related complications affect all body organ systems, including the penis. Diabetes-induced Erectile Dysfunction (ED) is caused by neuropathy of the penile nerves and vasculopathy involving the smooth muscle and endothelium of the corpus cavernosum. OBJECTIVE: This study aims to present an overview of Stem Cell (SC) research in diabetic animal models of ED, focusing on the function, signaling, and niches that have a prominent role in the regeneration of cavernosal cells and penile tissues. We highlight common erectile pathologies caused by diabetes and review relevant preclinical trials. We also discuss paracrine mechanisms of various SC therapies involved in the repair of endothelial cells and cavernous nerves in these diabetic models. METHODS: A PubMed search was performed, with dates ranging from inception until Mar 31, 2019. RESULTS: This review provides a comprehensive evaluation of the various strategies that have been investigated for improving SC delivery methods, through preclinical literature and published clinical trials regarding ED in men with diabetes. Various cell-type applications have benefited erectile function in diabetic models of ED. CONCLUSION: This review examines the progress and remaining challenges in diabetes-related SC research regarding ED. Moving forward, it is only with a combined effort of basic biology and translational work that the potential of SC-based therapies in diabetes in ED can be realized.

Ivabradine, the hyperpolarization-activated cyclic nucleotide-gated channel blocker, elicits relaxation of the human corpus cavernosum: a potential option for erectile dysfunction treatment.

OBJECTIVE: To evaluate the effect of the If channel inhibitor, ivabradine on human corpus cavernosum (HCC) smooth muscle tone. METHODS: HCC samples were obtained from erectile dysfunction(ED) patients (n = 12) undergoing penile prosthesis surgery. Concentration-response curves for ivabradine were exposed to various inhibitory and stimulatory agents. The relaxant and contractile responses to electrical field stimulation (EFS, 10 Hz and 80 Hz) were examined in the presence or absence of ivabradine (10 µM). HCN3 and HCN4 channel expression and localization were determined by Western blot and immunohistochemical analyses of HCC tissues. RESULTS: Increasing ivabradine concentrations dependently reduced the maximal contractile responses of isolated HCC strips induced by KCl (59.5 ± 2.5%) and phenylephrine (84.0 ± 9.8%), which was not affected by nitric oxide synthase and soluble guanylyl cyclase inhibitors after phenylephrine-induced contraction. Nifedipine and tetraethylammonium inhibited the maximum relaxation to ivabradine by 75% and 39.3%, respectively. Fasudil and sildenafil increased the relaxation response to ivabradine without altering the maximum response. Pre-incubation with ivabradine significantly increased relaxant responses to EFS (p < 0.01) and reduced the contractile tension evoked by EFS (72.3%) (p < 0.001). Ivabradine incubation did not affect the expression and localization of HCN3 and HCN4 channels in the HCC smooth muscle cells. CONCLUSIONS: Ivabradine exhibits a relaxant effect on HCC tissues, which is likely to be attributed to the blocking of L-type Ca2+ channels and the opening of K+ channels, independent of changes in the activation of the nitric oxide/cyclic guanosine monophosphate system. Inhibition of HCN channels localized in cavernosal smooth muscle cells may offer pharmacological benefits for patients with cardiovascular risk factors.

Evaluation of relaxant responses properties of cinnamon essential oil and its major component, cinnamaldehyde on human and rat corpus cavernosum

ABSTRACT Cinnamomum cassia (Cinnamon) is a well-known traditional medicine with therapeutic benefits for centuries. We evaluated the effects of cinnamon essential oil (CEO) and its main component cinnamaldehyde (CA) on human corpus cavernosum (HCC) and rat CC. The essential oil of cinnamon was analyzed for the confirmation of the oil profile. HCC specimens from patients undergoing penile prosthesis surgery (age 48-69 years) were utilized for functional studies. In addition, erectile responses in anesthetized control and diabetic rats were evaluated in vivo after intracavernosal injection of CEO and CA, and rat CC strips were placed in organ baths. After precontraction with phenylephrine (10µM), relaxant responses to CEO and CA were investigated. CA (96.9%) was found as the major component. The maximum relaxation responses to CEO and CA were 96.4±3.5% and 96.0±5.0% in HCC and 97.5±5.5% and 96.8±4.8% in rat CC, respectively. There was no difference between control and diabetic rats in relaxation responses to CEO and CA. The relaxant responses obtained with essential oil and CA were not attenuated in the presence of nitric oxide synthase (NOS) inhibitor, and soluble guanylate cyclase inhibitor (sGS) in CC. In vivo, erectile responses in diabetic rats were lower than in control rats, which was restored after intracavernosal injection of CEO and CA. CEO and CA improved erectile function and relaxation of isolated strips of rat CC and HCC by a NO/cGMP-independent mechanism. Further investigations are warranted to fully elucidate the restorative effects of CEO and CA on diabetic erectile dysfunction.