Human Corpus Cavernosum Tissue Research Articles

Penile cavernous sinusoids are Prox1-positive hybrid vessels.

Endothelial cells (ECs) of blood and lymphatic vessels have distinct identity markers that define their specialized functions. Recently, hybrid vasculatures with both blood and lymphatic vessel-specific features have been discovered in multiple tissues. Here, we identify the penile cavernous sinusoidal vessels (pc-Ss) as a new hybrid vascular bed expressing key lymphatic EC identity genes Prox1, Vegfr3,and Lyve1. Using single-cell transcriptome data of human corpus cavernosum tissue, we found heterogeneity within pc-S endothelia and observed distinct transcriptional alterations related to inflammatory processes in hybrid ECs in erectile dysfunction associated with diabetes. Molecular, ultrastructural, and functional studies further established hybrid identity of pc-Ss in mouse, and revealed their morphological adaptations and ability to perform lymphatic-like function in draining high-molecular-weight tracers. Interestingly, we found that inhibition of the key lymphangiogenic growth factor VEGF-C did not block the development of pc-Ss in mice, distinguishing them from other lymphatic and hybrid vessels analyzed so far. Our findings provide a detailed molecular characterization of hybrid pc-Ss and pave the way for the identification of molecular targets for therapies in conditions of dysregulated penile vasculature, including erectile dysfunction.

MP27-05 ANDROGEN RECEPTOR SIGNALING IN THE HUMAN PENIS IS SIMILAR REGARDLESS OF SERUM TESTOSTERONE LEVEL

You have accessJournal of UrologyCME1 Apr 2023MP27-05 ANDROGEN RECEPTOR SIGNALING IN THE HUMAN PENIS IS SIMILAR REGARDLESS OF SERUM TESTOSTERONE LEVEL Katherine Campbell, Alexandra Dullea, Braian Ledesma, Kajal Khodamoradi, Himanshu Arora, and Ranjith Ramasamy Katherine CampbellKatherine Campbell More articles by this author , Alexandra DulleaAlexandra Dullea More articles by this author , Braian LedesmaBraian Ledesma More articles by this author , Kajal KhodamoradiKajal Khodamoradi More articles by this author , Himanshu AroraHimanshu Arora More articles by this author , and Ranjith RamasamyRanjith Ramasamy More articles by this author View All Author Informationhttps://doi.org/10.1097/JU.0000000000003255.05AboutPDF ToolsAdd to favoritesDownload CitationsTrack CitationsPermissionsReprints ShareFacebookLinked InTwitterEmail Abstract INTRODUCTION AND OBJECTIVE: Testosterone (T) plays an important role in the proper development and maintenance of male reproductive tissues. The normal serum testosterone levels can vary between 300 to 1000 ng/dL. However, it is unclear whether androgen receptor (AR) signaling varies based on serum T levels. The aim of this study was to assess the impact of varied serum testosterone levels on AR signaling in Human Corpus Cavernosum tissue. Based on our previous work on the Androgen Saturation hypothesis, we hypothesized that above 200 ng/dL, AR signaling would not vary. METHODS: We obtained corpus spongiosum biopsies from men undergoing inflatable penile prosthesis placement for high grade erectile dysfunction. After mechanical dispersion of tissue with a homogenizer, the total protein was extracted using RIPA buffer. Quantitative detection of VEGF (Vascular endothelial growth factor), an androgen receptor marker, and AR (Androgen Receptor) expression was evaluated by western blot. The density of the bands in all the blots was quantified using densitometry analysis with ImageJ software. RESULTS: The median age of participants was 60.7 (57.6, 65.9) years. The median serum testosterone level was 378 (257, 419) ng/dl. The western blot results (Figure 1) showed no association in the expression level of VEGF or AR regardless of the serum testosterone level. CONCLUSIONS: Even with a wide range of serum testosterone levels (209-1478 ng/dl), androgen receptor signaling was similar in penile tissue. The results of this study support our previous work to demonstrate that AR signaling may be similar regardless of T level above 200 ng/dL. This suggests that serum testosterone levels might not reflect downstream androgen receptor signaling within the penile tissue. Understanding the AR saturation hypothesis provides important context necessary for appropriate prescribing of exogenous testosterone replacement therapy to optimize patient outcomes. Markers of androgen receptor signaling in tissue could be similar regardless of serum testosterone levels. Therefore, the utility of only serum testosterone levels in considering the effect of testosterone therapy needs to be re-evaluated. Source of Funding: This work was supported by: NIH Grant R01 DK130991 and Clinician Scientist Development Grant from the ACS to Ranjith Ramasamy, SMSNA Sexual Medicine Grant to Kajal Khodamoradi © 2023 by American Urological Association Education and Research, Inc.FiguresReferencesRelatedDetails Volume 209Issue Supplement 4April 2023Page: e363 Advertisement Copyright & Permissions© 2023 by American Urological Association Education and Research, Inc.MetricsAuthor Information Katherine Campbell More articles by this author Alexandra Dullea More articles by this author Braian Ledesma More articles by this author Kajal Khodamoradi More articles by this author Himanshu Arora More articles by this author Ranjith Ramasamy More articles by this author Expand All Advertisement PDF downloadLoading ...

MP27-06 BROMELAIN INDUCES RELAXATION OF HUMAN CORPUS CAVERNOSUM TISSUE IN VITRO INDEPENDENT NITRIC OXIDE-CGMP PATHWAY: POSSIBLE SIGNIFICANCE FOR ERECTILE DYSFUNCTION

You have accessJournal of UrologyCME1 Apr 2023MP27-06 BROMELAIN INDUCES RELAXATION OF HUMAN CORPUS CAVERNOSUM TISSUE IN VITRO INDEPENDENT NITRIC OXIDE-CGMP PATHWAY: POSSIBLE SIGNIFICANCE FOR ERECTILE DYSFUNCTION Serap Gur, Suresh C. Sikka, Asim B. Abdel-Mageed, Didem Yilmaz-Oral, Sudha Talwar, and Wayne J.G. Hellstrom Serap GurSerap Gur More articles by this author , Suresh C. SikkaSuresh C. Sikka More articles by this author , Asim B. Abdel-MageedAsim B. Abdel-Mageed More articles by this author , Didem Yilmaz-OralDidem Yilmaz-Oral More articles by this author , Sudha TalwarSudha Talwar More articles by this author , and Wayne J.G. HellstromWayne J.G. Hellstrom More articles by this author View All Author Informationhttps://doi.org/10.1097/JU.0000000000003255.06AboutPDF ToolsAdd to favoritesDownload CitationsTrack CitationsPermissionsReprints ShareFacebookLinked InTwitterEmail Abstract INTRODUCTION AND OBJECTIVE: Bromelain (BRM) is a mixture of proteolytic enzymes found in several parts of the pineapple (Ananas comosus) plant. BRM is widely administered for its well-recognized properties, mainly anti-inflammatory, antithrombotic and fibrinolytic, anticancer, and immunomodulatory. BRM gained universal acceptance as a phytotherapeutic agent due to its extensive dietary usage and lack of side effects; however, the complete molecular mechanism of action of BRM has not been completely identified. This exploratory study focuses on the erectile responses of human cavernosal strips on isometric tension measurements. In this study, we aimed to evaluate the effectiveness of (a) pure BRM (from pineapple stem, Sigma-Aldrich, St Louis, MO), (b) BRM dietary supplement (BG, Natural Brand Bromelain 500mg tablet, GNC, Pittsburgh, PA) and (c) fresh pineapple juice (PAJ) on human corpus cavernosum (HCC). METHODS: HCC tissues were obtained from men undergoing penile prosthesis implantation (n =8-10) and prepared for organ bath experiments as per our published procedures. BRM-induced relaxation response (10-8-10-3 M) was performed in vitro using HCC strips in an organ bath. The effects of inhibitors [NG-nitro-L-arginine methyl ester (L-NAME, 100µM), 1H-[1,2,4]-oxadiazolole-[4,3-a] quinoxalin-10one (ODQ, 30µM), and tetraethylammonium (TEA, 100 µM, blocker Ca2+ - activated K+channels)] on BRM-mediated relaxation responses were evaluated. The relaxation effects of BRM, BG, and PAJ on phenylephrine (Phe)-induced contraction were also compared. The protein expression of endothelial (e) and neuronal (n) nitric oxide synthase (NOS) and vascular endothelium growh factor (VEGF) were determined using Western blotting and immunohistochemistry. RESULTS: BRM inhibited Phe-evoked contractions in a dose-dependent manner. All agents induced relaxation of HCC (maximum response: BRM- 62.87 ± 6.23%, BG - 61.95 ± 4.17%, PAJ -55.68 ± 5.52%) after Phe-contraction. Inhibitors of nitric oxide (L-NAME) and soluble guanylate cyclase (ODQ) as well as TEA failed to affect the BRM-induced HCC relaxations. The relaxant responses of HCC strips were observed in the presence or the absence of BRM products. Furthermore, eNOS and nNOS protein levels were decreased and were not restored after BRM, while VEGF levels remained unaltered. CONCLUSIONS: These data suggest that BRM have the capacity to exert in vitro penile relaxations. The underlying mechanism of BRM is likely independent of the nitric oxide-cyclic guanosine monophosphate pathway. Overall, these in vitro studies suggested that consumption of BRM and its supplements may represent a novel strategy to prevent and treat erectile dysfunction in men, especially due to inflammatory issues. Source of Funding: None © 2023 by American Urological Association Education and Research, Inc.FiguresReferencesRelatedDetails Volume 209Issue Supplement 4April 2023Page: e364 Advertisement Copyright & Permissions© 2023 by American Urological Association Education and Research, Inc.MetricsAuthor Information Serap Gur More articles by this author Suresh C. Sikka More articles by this author Asim B. Abdel-Mageed More articles by this author Didem Yilmaz-Oral More articles by this author Sudha Talwar More articles by this author Wayne J.G. Hellstrom More articles by this author Expand All Advertisement PDF downloadLoading ...

PS-3-8 Testosterone Induces Relaxation of Human Corpus Cavernosum Tissue of Patients With Erectile Dysfunction

Previous research in the field of cardiovascular diseases suggests a relaxing effect of testosterone (T) on smooth muscle cells. Therefore, it was hypothesized that T could play a significant role in erection development. We aimed to investigate the relaxing effect of T and other molecules of the T signaling pathway on human corpus cavernosum (HCC) tissue. Samples of HCC tissue were obtained from men who underwent penile prosthesis implantation (n = 33) for erectile dysfunction. Samples were used for Isometric Tension Measurement Ex Vivo experiments. Following standardized precontraction with phenylephrine, increasing doses of T or dihydrotestosterone (DHT) were administered and blocked by NO/H2S synthesis inhibitors, a KATP blocker and flutamide (androgen receptor inhibitor). A dose-dependent relaxing effect of DHT and T was observed with a relaxation of respectively 24.9% ± 23.4% (P < 0.0001) and 41.7% ± 19.1% (P=0.01) compared to 6.8% ± 15.9% for vehicle (DMSO) at 300 μM. The relaxing effect of T was not countered by blocking NO synthesis, H2S synthesis, KATP channels or the androgen receptor. Strength of the study is the use of fresh HCC tissues with reproducible results. Limitation is the need of supraphysiological T levels to induce the observed effect.

Testosterone Induces Relaxation of Human Corpus Cavernosum Tissue of Patients With Erectile Dysfunction.

IntroductionPrevious research in the field of cardiovascular diseases suggests a relaxing effect of testosterone (T) on smooth muscle cells. Therefore, it was hypothesized that T could play a significant role in erection development.AimTo investigate the relaxing effect of T and other molecules of the T signaling pathway on human corpus cavernosum (HCC) tissue.MethodsSamples of the HCC tissue were obtained from men who underwent penile prosthesis implantation (n = 33) for erectile dysfunction. Samples were used for isometric tension measurement in Ex Vivo experiments. Following standardized precontraction with phenylephrine, increasing doses of T or dihydrotestosterone were administered and blocked by NO/H2S synthesis inhibitors, a KATP blocker, and flutamide (androgen receptor inhibitor).Main Outcome MeasureThe outcome was relaxation of the HCC tissue, normalized to a maximum precontraction achieved by phenylephrine.ResultsA dose-dependent relaxing effect of dihydrotestosterone and T was observed with a relaxation of, respectively, 24.9% ± 23.4% (P < .0001) and 41.7% ± 19.1% (P = .01) compared with 6.8% ± 15.9% for vehicle (dimethylsulfoxide) at 300 μM. The relaxing effect of T was not countered by blocking NO synthesis, H2S synthesis, KATP channels, or the androgen receptor.Clinical ImplicationsBy understanding the underlying mechanisms of T-induced HCC relaxation, potential new therapeutic targets can be identified.Strengths & LimitationsThe strength of the study is the use of fresh HCC tissues with reproducible results. The limitation is the need for supraphysiological T levels to induce the observed effect.ConclusionRapid androgen-induced relaxation of HCC is likely to occur via nongenomic mechanisms. Previously suggested mechanisms of action by which T modulates HCC relaxation have been excluded.Van den Broeck T, Soebadi MA, Falter A, et al. Testosterone Induces Relaxation of Human Corpus Cavernosum Tissue of Patients With Erectile Dysfunction. J Sex Med 2019; 8:114–119.

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 I f 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.

PO-01-064 Testosterone relaxes human corpus cavernosum tissue of patients with erectile dysfunction

To investigate the effect of testosterone (T) on relaxation of human corpus cavernosum tissue. Human corpus cavernosum tissue samples were obtained after consent from men undergoing penile prosthesis implantation (n=46) for organ bath experiments. Tissue strips were precontracted with phenylephrine after which increasing doses of T, DHT, and androstenedione were added. Blockade of androgen receptor as well as hydrogen sulfide and nitric oxide biosynthesis was studied. Fifteen minutes after addition of the different compounds, tissue relaxation was measured. Results are expressed as mean+/-SD. Statistical analysis was performed using unpaired t-test. T relaxed precontracted tissues with 70.7+/-16.9 % (p = 0.003) at 300 microM compared to DMSO vehicle only. Addition of 300 microM of androstenedione (p = 0.17) and DHT (p=0.09) resulted in no significant difference in relaxation compared to T. Maximum relaxation response to T were not inhibited by N (G)-nitro-L-arginine methyl ester (p = 0.16), beta-cyanoalanine (p = 0.16), propargylglycine (p=0.34) and glibenclamide (p=0.73). The addition of 350 nanoM flutamide (androgen receptor inhibitor) did not alter the effect of T on tissue relaxation with 80.2 +/- 26.5% of relaxation compared to T alone (p = 0.25).

084 Bromelain Induces Relaxation of Human Corpus Cavernosum Tissue in Vitro Independent Nitric Oxide-cGMP Pathway: Possible Significance for Erectile Dysfunction

Bromelain (BRM) is a mixture of proteolytic enzymes found in several parts of the pineapple (Ananas comosus) plant. BRM is widely administered for its well-recognized properties, mainly anti-inflammatory, antithrombotic and fibrinolytic, anticancer, and immunomodulatory. BRM gained universal acceptance as a phytotherapeutic agent due to its extensive dietary usage and lack of side effects; however, the complete molecular mechanism of action of BRM has not been completely identified. This exploratory study focuses on the erectile responses of human cavernosal strips on isometric tension measurements. To evaluate the effectiveness of (a) pure BRM (from pineapple stem, Sigma-Aldrich, St Louis, MO), (b) BRM dietary supplement (BG, Natural Brand Bromelain 500mg tablet, GNC, Pittsburgh, PA) and (c) fresh pineapple juice (PAJ) on human corpus cavernosum (HCC). HCC tissues were obtained from men undergoing penile prosthesis implantation (n =8-10) and prepared for organ bath experiments as per our published procedures. BRM-induced relaxation response (10−8-10−3 M) was performed in vitro using HCC strips in an organ bath. The effects of inhibitors [NG-nitro-L-arginine methyl ester (L-NAME, 100μM), 1H-[1,2,4]-oxadiazolole-[4,3-a] quinoxalin-10one (ODQ, 30μM), and tetraethylammonium (TEA, 100 μM, blocker Ca2+ - activated K+ channels)] on BRM-mediated relaxation responses were evaluated. The relaxation effects of BRM, BG, and PAJ on phenylephrine (Phe)-induced contraction were also compared. The protein expression of endothelial (e) and neuronal (n) nitric oxide synthase (NOS) markers and vascular endothelium growth factor (VEGF) were determined using Western blotting and immunohistochemistry.

A Simple and Nonenzymatic Method to Isolate Human Corpus Cavernosum Endothelial Cells and Pericytes for the Study of Erectile Dysfunction.

PurposeTo establish a simple and nonenzymatic technique to isolate endothelial cells (ECs) and pericytes from human corpus cavernosum tissue and to evaluate the angiogenic ability of the human cavernous EC or pericytes for the study of high glucose-induced angiopathy.Materials and MethodsFor primary human cavernous EC culture, cavernous tissues were implanted into Matrigel in dishes. For primary human cavernous pericyte culture, cavernous tissues were settled by gravity into dishes. We performed immunocytochemistry and Western blot to determine phenotype and morphologic changes from passage 1 to 5. The primary cultured cells were exposed to a normal-glucose (5 mmol/L) or a high-glucose (30 mmol/L) condition, and then tube formation assay was done.ResultsWe successfully isolated high-purity EC and pericytes from human corpus cavernosum tissue. Primary cultured EC showed highly positive staining for von Willebrand factor, and pericyte revealed positive staining for NG2 and platelet-derived growth factor receptor-β. Primary cultured EC and pericytes maintained their cellular characteristics up to passage 2 or 3. However, we observed significant changes in their typical phenotype from the passage 4 and morphological characteristics from the passage 3. Human cavernous EC or pericytes formed well-organized capillary-like structures in normal-glucose condition, whereas severely impaired tube formation was detected in high-glucose condition.ConclusionsThis study provides a simple and nonenzymatic method for primary culture of human cavernous EC and pericytes. Our study will aid us to understand the pathophysiology of diabetic erectile dysfunction, and also be a valuable tool for determining the efficacy of candidate therapeutic targets.

163 Effect of the Cranberry (Vaccinium Macrocarpon) Extract on the Relaxation of Human Corpus Cavernosum Tissue in Vitro: Can Cranberries Contribute to Reduce the Incidence of Erectile Dysfunction?

163 Effect of the Cranberry (Vaccinium Macrocarpon) Extract on the Relaxation of Human Corpus Cavernosum Tissue in Vitro: Can Cranberries Contribute to Reduce the Incidence of Erectile Dysfunction?

The pericyte as a cellular regulator of penile erection and a novel therapeutic target for erectile dysfunction.

Pericytes are known to play critical roles in vascular development and homeostasis. However, the distribution of cavernous pericytes and their roles in penile erection is unclear. Herein we report that the pericytes are abundantly distributed in microvessels of the subtunical area and dorsal nerve bundle of mice, followed by dorsal vein and cavernous sinusoids. We further confirmed the presence of pericytes in human corpus cavernosum tissue and successfully isolated pericytes from mouse penis. Cavernous pericyte contents from diabetic mice and tube formation of cultured pericytes in high glucose condition were greatly reduced compared with those in normal conditions. Suppression of pericyte function with anti-PDGFR-β blocking antibody deteriorated erectile function and tube formation in vivo and in vitro diabetic condition. In contrast, enhanced pericyte function with HGF protein restored cavernous pericyte content in diabetic mice, and significantly decreased cavernous permeability in diabetic mice and in pericytes-endothelial cell co-culture system, which induced significant recovery of erectile function. Overall, these findings showed the presence and distribution of pericytes in the penis of normal or pathologic condition and documented their role in the regulation of cavernous permeability and penile erection, which ultimately explore novel therapeutics of erectile dysfunction targeting pericyte function.

MP52-03 THE PERICYTES AS A CELLULAR REGULATOR OF PENILE ERECTION AND A NOVEL THERAPEUTIC TARGET FOR ERECTILE DYSFUNCTION

You have accessJournal of UrologySexual Function/Dysfunction/Andrology: Basic Research I1 Apr 2015MP52-03 THE PERICYTES AS A CELLULAR REGULATOR OF PENILE ERECTION AND A NOVEL THERAPEUTIC TARGET FOR ERECTILE DYSFUNCTION Guo Nan Yin, Nando Dulal Das, Min Ji Choi, Kang-Moon Song, Mi-Hye Kwon, Jiyeon Ock, Anita Limanjaya, Kalyan Ghatak, Woo Jean Kim, Soo-Hwan Park, Jae Seog Hyun, Ji-Kan Ryu, and Jun-Kyu Suh Guo Nan YinGuo Nan Yin More articles by this author , Nando Dulal DasNando Dulal Das More articles by this author , Min Ji ChoiMin Ji Choi More articles by this author , Kang-Moon SongKang-Moon Song More articles by this author , Mi-Hye KwonMi-Hye Kwon More articles by this author , Jiyeon OckJiyeon Ock More articles by this author , Anita LimanjayaAnita Limanjaya More articles by this author , Kalyan GhatakKalyan Ghatak More articles by this author , Woo Jean KimWoo Jean Kim More articles by this author , Soo-Hwan ParkSoo-Hwan Park More articles by this author , Jae Seog HyunJae Seog Hyun More articles by this author , Ji-Kan RyuJi-Kan Ryu More articles by this author , and Jun-Kyu SuhJun-Kyu Suh More articles by this author View All Author Informationhttps://doi.org/10.1016/j.juro.2015.02.1720AboutPDF ToolsAdd to favoritesDownload CitationsTrack CitationsPermissionsReprints ShareFacebookTwitterLinked InEmail INTRODUCTION AND OBJECTIVES Pericytes are known to play critical roles in vascular development and homeostasis. The aim of this study was to examine the differential expression of pericytes in the penis and their functional roles in penile erection. METHODS The diabetic mice were treated with hepatocyte growth factor (HGF) protein to enhance pericyte function and normal mice received anti-platelet-derived growth factor receptor-beta (PDGFR-β) blocking antibody to inhibit pericyte function. Erectile function was measured by electrical stimulation of the cavernous nerve. Penile tissue was obtained from diabetic mice and from patients with psychogenic erectile dysfunction. The differential distribution of pericytes in mouse and human penis was determined. Data were analyzed by using Mann–Whitney U-tests or one-way analysis of variance. RESULTS Pericytes were abundantly distributed in microvessels of the subtunical area and dorsal nerve bundle of mice, followed by dorsal vein and cavernous sinusoids. We further confirmed the presence of pericytes in human corpus cavernosum tissue and successfully isolated pericytes from mouse penis. Inhibition of pericyte function with anti-PDGFR-β blocking antibody induced deterioration of erectile function in normal mice. In contrast, HGF protein restored cavernous pericyte content in diabetic mice, and significantly decreased cavernous vascular permeability in diabetic mice in vivo and in pericytes-endothelial cell co-culture system in vitro, which induced significant recovery of erectile function. CONCLUSIONS Pericyte gain- and loss-of-function studies suggest that the functional and structural integrity of pericytes are critical for maintaining penile erection. © 2015 by American Urological Association Education and Research, Inc.FiguresReferencesRelatedDetails Volume 193Issue 4SApril 2015Page: e628-e629 Advertisement Copyright & Permissions© 2015 by American Urological Association Education and Research, Inc.MetricsAuthor Information Guo Nan Yin More articles by this author Nando Dulal Das More articles by this author Min Ji Choi More articles by this author Kang-Moon Song More articles by this author Mi-Hye Kwon More articles by this author Jiyeon Ock More articles by this author Anita Limanjaya More articles by this author Kalyan Ghatak More articles by this author Woo Jean Kim More articles by this author Soo-Hwan Park More articles by this author Jae Seog Hyun More articles by this author Ji-Kan Ryu More articles by this author Jun-Kyu Suh More articles by this author Expand All Advertisement Advertisement PDF downloadLoading ...

Synergistic Effects of BAY 60-4552 and Vardenafil on Relaxation of Corpus Cavernosum Tissue of Patients with Erectile Dysfunction and Clinical Phosphodiesterase Type 5 Inhibitor Failure

Overall efficacy rates of phosphodiesterase type 5 inhibitors (PDE5-i) for erectile dysfunction (ED) are 60-70%. PDE5-i treatment failures currently have to resort to invasive treatment options for restoration of erectile function. AIMS.: To assess changes in the nitric oxide (NO)/cyclic guanosine monophosphate (cGMP)/protein kinase (PKG) pathway in human corpus cavernosum (HCC) of PDE5-i nonresponders compared with healthy controls. To evaluate the effects of BAY 60-4552, a stimulator of soluble guanylate cyclase (sGC), and vardenafil on relaxation of HCC strips from PDE5-i nonresponders. mRNA expression, morphological localization of the NO/cGMP/PKG pathway, and relaxant capacity of both compounds alone or combined. Analysis of variance, t-test or Mann-Whitney test based upon number of groups and normality of data. HCC tissues were harvested after consent from individuals undergoing penile prosthesis implantation (patients) and potent patients undergoing transurethral surgery (healthy controls, needle biopsy). HCC tissues of patients were compared with those of healthy controls for the expression of mRNA coding for PDE5A, eNOS, PKGα1, PKG2, sGCα1, sGCα2, sGCβ1, sGCβ2, α-smooth muscle actin (aSMA) and β-actin by quantitative polymerase chain reaction (qPCR). The respective proteins were localized using immunofluorescence. Tissue strips of patients were precontracted with phenylepinephrine followed by incubation with 1 μM of either vardenafil or BAY 60-4552, or both simultaneously. The main targets in the NO/cGMP/sGC pathway were downregulated in PDE5-i nonresponders. The pathway was morphologically located to HCC smooth muscle, of which the overall content was preserved in ED patients based on aSMA expression. BAY 60-4552 and vardenafil have synergistic effects on relaxation of HCC of PDE5-i nonresponders. The main limitation is the small amount of control tissue precluding functional testing on these samples. Despite downregulation of the NO/cGMP/PKG pathway, combining BAY 60-4552 with vardenafil significantly enhanced relaxation HCC strips of PDE5-i nonresponders.

817 UROTENSIN II AS A POSSIBLE SERUM MARKER OF ERECTILE DYSFUNCTION

You have accessJournal of UrologySexual Function/Dysfunction/Andrology: Basic Research (I)1 Apr 2013817 UROTENSIN II AS A POSSIBLE SERUM MARKER OF ERECTILE DYSFUNCTION Paolo Verze, Ferdinando Fusco, Roberta D'Emanuele Di Villabianca, Emma Mitidieri, Giuseppe Cirino, Raffaella Sorrentino, Ciro Imbimbo, Marco Franco, and Vincenzo Mirone Paolo VerzePaolo Verze Naples, Italy More articles by this author , Ferdinando FuscoFerdinando Fusco Naples, Italy More articles by this author , Roberta D'Emanuele Di VillabiancaRoberta D'Emanuele Di Villabianca Naples, Italy More articles by this author , Emma MitidieriEmma Mitidieri Naples, Italy More articles by this author , Giuseppe CirinoGiuseppe Cirino Naples, Italy More articles by this author , Raffaella SorrentinoRaffaella Sorrentino Naples, Italy More articles by this author , Ciro ImbimboCiro Imbimbo Naples, Italy More articles by this author , Marco FrancoMarco Franco Naples, Italy More articles by this author , and Vincenzo MironeVincenzo Mirone Naples, Italy More articles by this author View All Author Informationhttps://doi.org/10.1016/j.juro.2013.02.383AboutPDF ToolsAdd to favoritesDownload CitationsTrack CitationsPermissionsReprints ShareFacebookTwitterLinked InEmail INTRODUCTION AND OBJECTIVES U-II was identified as the natural ligand of a G-protein coupled receptor, namely UT receptor. U-II and UT receptor are expressed in a variety of peripheral organs and especially in cardiovascular tissue and their expression is up-regulated in human cardiovascular disease, including congestive heart failure, hypertension, type II diabetes and diabetic nephropathy. Recent evidence indicates that the U-II/UT pathway has a vasodilator effect on human corpus cavernosum tissue, and this effect is mediated by eNOS. The Purpose of this study is to measure the plasma level of U-II in men with ED compared to healthy controls and to correlate the values obtained with the IIEF score and other clinical variables and comobidities. METHODS A sample of 70 healthy volunteers and 80 ED patients have been enrolled. The ED patients underwent a standard visit at the Unit of Andrology of the University Federico II of Naples. Each patient was interviewed, exploring the presence of risk factors and comorbidities related to ED or to other diseases. Furthermore all patients were asked to complete the IIEF. The physical examination included BMI. Blood samples were obtained in the same day: a routine serum profile was performed, comprehensive of plasma level of U-II. RESULTS The results obtained from clinical study are reported as mean ± SD. The first result showing the difference between the UII plasma levels measured both in controls and ED patients,indicated that the mean values were 1662,06 pg/ml and 3513,21pg/ml respectively (ratio 2,11). A correlation test was performed to evaluate association between UII plasma values in ED patients and IIEF score. It was found a Pearson product-moment correlation coefficient (PPMCC) of −0,82 suggesting a strong, statistically significant, negative correlation between the IIEF score and The UII plasma levels. Correlation tests were made also between UII plasma levels and BMI, blood total cholesterol and glycemia. Results obtained showed a moderate, statistically significant, positive correlation with BMI (PPMCC=0,48); a small statistically significant positive correlation with Blood total cholesterol (PPMCC= 0,34)and no statistically significant correlation was founded with glycemia (PPMCC= 0,09). CONCLUSIONS UII plasma levels are doubled in ED patients compared to healthy controls and inversely correlated to IIEF score. Further studies are warranted to evaluate a possible role of urotensin II as serum marker of ED. © 2013 by American Urological Association Education and Research, Inc.FiguresReferencesRelatedDetails Volume 189Issue 4SApril 2013Page: e335-e336 Advertisement Copyright & Permissions© 2013 by American Urological Association Education and Research, Inc.MetricsAuthor Information Paolo Verze Naples, Italy More articles by this author Ferdinando Fusco Naples, Italy More articles by this author Roberta D'Emanuele Di Villabianca Naples, Italy More articles by this author Emma Mitidieri Naples, Italy More articles by this author Giuseppe Cirino Naples, Italy More articles by this author Raffaella Sorrentino Naples, Italy More articles by this author Ciro Imbimbo Naples, Italy More articles by this author Marco Franco Naples, Italy More articles by this author Vincenzo Mirone Naples, Italy More articles by this author Expand All Advertisement Advertisement PDF downloadLoading ...

Density and distribution of connexin 43 in corpus cavernosum tissue from diabetic and hypogonadal patients with erectile dysfunction.

Altered expression of connexin 43 (Cx43) has been postulated to be involved in the development and progression of various diseases including erectile dysfunction (ED). The aim of this study was to determine whether distribution and density of the gap junction protein Cx43 are altered in human corpus cavernosum (HCC) tissue samples derived from diabetic or hypogonadal patients with ED compared to those from normal subjects. HCC tissue sections derived from normal, diabetic and hypogonadal subjects were fixed in 4% formaldehyde, embedded in paraffin and immunostained with a monoclonal mouse anti-rat Cx43 antibody. Cx43 density was expressed as the cumulative number of gap junction plaques per unit area of tissue corrected for number of 4',6-diamidino-2-phenylindole, dihydrochloride-labeled smooth muscle cells (dots per unit area corrected for number of cells). The distribution of Cx43 plaques in smooth muscle was not affected in tissues derived from diabetic or hypogonadal subjects with ED compared with those from normal subjects. However, the number of Cx43 plaques was significantly reduced in HCC tissues derived from diabetic or hypogonadal subjects (73 ± 8% and 68 ± 11% of normal, respectively), indicating reduced Cx43 gap junctions in diabetic and hypogonadal subjects with ED. Cx43 density in the HCC was diminished in tissue samples derived from diabetic or hypogonadal patients with ED compared to tissue samples from normal non-diabetic subjects. This marked decrease in Cx43 gap junction channels may contribute to attenuated gap junction function and to diminished erectile physiology.

Inhibition of sympathetic neuroeffector transmission in human corpus cavernosum

What's known on the subject? and What does the study add? In the present study the mechanisms regulating EFS-evoked neurogenic contraction in the human corpus cavernosum (HCC) were investigated. Overall, our data adds to current knowledge that the NO-independent heme dependent activation of sGC and the RhoA/Rho-kinase signaling pathways play an important role in the regulation of neurogenic contractile activity in HCC tissue. To investigate the mechanisms of adrenergically mediated smooth muscle contraction in the human corpus cavernosum (HCC) using an organ bath approach. Human corpus cavernosum specimens were obtained from patients (aged 59-72 years) with erectile dysfunction (ED), undergoing penile prosthesis implantation surgery. Isolated HCC strips (1 × 1 × 6 mm) were suspended in tissue bath chambers for isometric tension recording. The effects of various drugs on neurogenic contractions evoked by electrical field stimulation (EFS) were investigated. The drugs included nitric oxide (NO) donors, phosphodiesterase 5 (PDE5) inhibitor, Rho kinase (ROCK) inhibitor, NO-independent stimulator, L-type Ca2+ channel blocker and α-receptor antagonist. Pre-incubation with the NO donor sodium nitroprusside (SNP; 10(4) M) significantly reduced the initial peak increase in tension evoked by EFS (by 71%, P < 0.05). The PDE5 inhibitor sildenafil (10(-4) M) reduced the increase in tension by 69%, while a combination of sildenafil and ROCK inhibitor, fasudil, inhibited tension by 81%. The EFS-induced contractile response at 80 Hz was decreased by 65% with fasudil and by 70% with isradipine (P < 0.001), while a combination of these drugs decreased the response by 88%. An NO-independent stimulator soluble guanylate cyclase (sGC), BAY 41-8543, significantly reduced the response (by 82%, P < 0.001) Phentolamine, an α-receptor antagonist, nearly eliminated the contractile response (98%, P < 0.001). These data suggest that neurogenic contractions are mediated by an increase in Ca(2+) influx via L-type voltage-gated Ca(2+) channels and that an increase in Ca(2+) sensitivity is mediated by the ROCK pathway and the PDE5 enzyme system as well as by the inhibitory NO/sGC/cGMP pathway. The neurogenic contractile response in HCC is mediated by several intracellular pathways, including adrenergic receptors, Ca(2+) entry, Ca(2+) sensitization and activation of the PDE5 enzyme. The Rho-kinase (ROCK) inhibitor fasudil, L-type Ca(2+) channel antagonist isradipine, and PDE5 inhibitor sildenafil, as well as a NO-independent stimulator of sGC, had similar inhibitory effects, suggesting parallel mechanisms in the HCC.

Effects of ethanol on the tonicity of corporal tissue and the intracellular Ca2+ concentration of human corporal smooth muscle cells

Heavy alcohol consumption is associated with an increased risk of erectile dysfunction (ED); however, the acute effects of ethanol (EtOH) on penile tissue are not fully understood. We sought to investigate the effects of EtOH on corporal tissue tonicity, as well as the intracellular Ca(2+) concentration ([Ca(2+)](i)) and potassium channel activity of corporal smooth muscle. Strips of corpus cavernosum (CC) from rabbits were mounted in organ baths for isometric tension studies. Electrical field stimulation (EFS) was applied to strips precontracted with 10 μmol L(-1) phenylephrine as a control. EtOH was then added to the organ bath and incubated before EFS. The [Ca(2+)](i) levels were monitored by the ratio of fura-2 fluorescence intensities using the fura-2 loading method. Single-channel and whole-cell currents were recorded by the conventional patch-clamp technique in short-term cultured smooth muscle cells from human CC tissue. The corpus cavernosal relaxant response of EFS was decreased in proportion to the concentration of EtOH. EtOH induced a sustained increase in [Ca(2+)](i) in a dose-dependent manner, Extracellular application of EtOH significantly increased whole-cell K(+) currents in a concentration-dependent manner (P < 0.05). EtOH also increased the open probability in cell-attached patches; however, in inside-out patches, the application of EtOH to the intracellular aspect of the patches induced slight inhibition of Ca(2+)-activated potassium channel (KCa) activity. EtOH caused a dose-dependent increase in cavernosal tension by alterations to [Ca(2+)](i). Although EtOH did not affect KCa channels directly, it increased the channel activity by increasing [Ca(2+)](i). The increased corpus cavernosal tone caused by EtOH might be one of the mechanisms of ED after heavy drinking.

Nebivolol Dilates Human Penile Arteries and Reverses Erectile Dysfunction in Diabetic Rats through Enhancement of Nitric Oxide Signaling

Traditional beta-blockers have sometimes been associated with erectile dysfunction (ED). Nebivolol is a cardioselective β(1)-adrenoceptor antagonist that promotes vasodilation through a nitric oxide (NO)-dependent mechanism. We evaluated the effects of nebivolol on the NO/cyclic guanosine monophosphate (cGMP) signaling pathway, on erectile function and dysfunction, and in human penile vascular tissues. Erectile response to cavernosal nerve electrical stimulation in control and diabetes-induced ED rats were evaluated, along with serum nitrite/nitrate (NOx) concentration and plasma/tissue cGMP levels. Endothelium-dependent and sildenafil-induced relaxation of isolated human corpus cavernosum (HCC) and human penile resistance arteries (HPRA) were also determined. The effects of nebivolol on erectile function and dysfunction and on NO/cGMP-mediated responses. Treatment with nebivolol significantly potentiated erectile response in control rats, regardless of its effects on blood pressure. Nebivolol increased NOx and plasma cGMP by 3-fold and 2.75-fold, respectively, and significantly augmented the elevation of plasma cGMP produced by sildenafil. Nebivolol enhanced endothelium-dependent and sildenafil-induced relaxations of HCC tissue, and produced endothelium-dependent vasodilation of HPRA. Nebivolol, but not atenolol, significantly improved erectile response in diabetic rats (51.6%, 53.2%, and 87.1% of response at 3 Hz in nondiabetic rats, for vehicle-treated, atenolol-treated, and nebivolol-treated diabetic rats, respectively); after sildenafil administration, ED was completely reversed in nebivolol-treated diabetic rats (69.6% and 112% for diabetic rats treated with sildenafil and nebivolol plus sildenafil, respectively). Accordingly, nebivolol restored systemic NOx levels and cGMP content in penile tissue from these animals. Nebivolol in vivo activated the NO/cGMP pathway, enhanced erectile response and reversed ED in diabetic rats. Moreover, nebivolol in vitro potentiated NO/cGMP-mediated relaxation of human erectile tissues. These effects may account for the low incidence of ED in nebivolol-treated hypertensive patients. Nebivolol therefore may have utility in the treatment of ED, particularly ED associated with diabetes.

Contractility of Diabetic Human Corpus Cavernosum Smooth Muscle in Response to Serotonin Mediated via Rho-Kinase

Background/Aims: Serotonin (5-hydroxytryptamine, 5-HT)-induced contraction and the involvement of RhoA/Rho-kinase pathway in the 5-HT-induced contraction was investigated isometrically in vitro in both diabetic and nondiabetic human corpus cavernosum (HCC) tissues. Methods: HCC tissues were obtained from 12 patients. The response to 5-HT (10^–9 to 10^–5 mol/l) was studied in isolated HCC tissues in the absence and in the presence of a Rho-kinase inhibitor (Y-27632). Results: Preincubation with Y-27632 attenuated maximum contractions induced by 5-HT in tissues of both nondiabetics and diabetics. When diabetic and nondiabetic groups were compared, no significant difference was seen in 5-HT-induced contraction alone, but in the presence of Y-27632, 5-HT-induced contraction was significantly higher in the diabetic group. Conclusion: These results suggest that the Rho-kinase-mediated pathway plays an important role for 5-HT-induced contraction in diabetic corpus cavernosum tissues.

Comparative Relaxing Effects of Sildenafil, Vardenafil, and Tadalafil in Human Corpus Cavernosum: Contribution of Endogenous Nitric Oxide Release

To compare the direct relaxant activity of sildenafil, vardenafil, and tadalafil in the human corpus cavernosum (HCC) and to investigate their modulatory effects on nitric oxide (NO)-mediated responses. Phosphodiesterase (PDE)-5 inhibitors cause cavernosal smooth muscle relaxation and penile erection. HCC strips were mounted in 10-mL organ baths containing Krebs solution and connected to force-displacement transducers. The changes in isometric force were recorded using the Powerlab 400 data acquisition system. Corporeal smooth muscle was precontracted submaximally with phenylephrine (10 micromol/L). All PDE-5 inhibitors tested (0.001-10 micromol/L) relaxed phenylephrine-precontracted HCC with similar values of potency in a concentration-dependent manner. However, the maximal relaxations induced by tadalafil (83% +/- 4%) were significantly lower compared with sildenafil (107% +/- 5%) and vardenafil (111% +/- 3%). The NO synthesis inhibitor N-nitro-l-arginine methyl ester (100 micromol/L) caused significant rightward shifts in the concentration-response curves for sildenafil (4.0-fold), vardenafil (4.6-fold), and tadalafil (3.2-fold) in HCC tissue. The guanylyl cyclase inhibitor 1H-[1,2,4]oxadiazolo[4,3-a]quinoxalin-1-one (10 micromol/L) also produced similar rightward shifts for these PDE-5 inhibitors. The cavernosal relaxations evoked by either acetylcholine or the NO donor glyceryl trinitrate were markedly potentiated by sildenafil, vardenafil, and tadalafil (0.1 micromol/L each). All PDE-5 inhibitors significantly increased the duration of electrical field stimulation-induced relaxations (8 Hz). Our findings have shown that sildenafil, vardenafil, and tadalafil relax HCC tissues in a concentration-dependent manner, but the maximal relaxation obtained with tadalafil was significantly lower than that obtained with sildenafil and vardenafil. Moreover, the PDE-5 inhibitors interacted with endogenous and exogenous NO, amplifying its HCC relaxation.