Cavernosal Tissue Research Articles

Quercetin treatment against ischemia/reperfusion injury in rat corpus cavernosum tissue: a role on apoptosis and oxidative stress

Reactive oxygen metabolites play an important role in the ischemia/reperfusion (I/R)-induced tissue injury. This study was designed to investigate the possible protective effects of quercetin against I/R injury of the rat corpus cavernosum tissue. To induce I/R injury, abdominal aorta was clamped for 30 min and reperfused for 60 min. Quercetin (20 mg/kg) or vehicle was given before ischemia and just after reperfusion in the I/R group and in the sham-operated control group in which clamping was not performed. After decapitation, corpus cavernosum tissues were removed and either placed in organ baths or stored for evaluating biochemical parameters. Oxidative injury was examined by measuring lucigenin chemiluminescence (CL), nitric oxide (NO), malondialdehyde (MDA) and glutathione (GSH) levels, superoxide dismutase (SOD) and myeloperoxidase (MPO) activities and caspase-3 protein levels. In the I/R group, contractile responses to phenylephrine and relaxation responses to carbachol were impaired significantly compared with those in the control groups, while quercetin treatment in I/R group reversed both of the responses. On the other hand, increase in lucigenin CL, NO, MDA levels and MPO and caspase-3 activities and decrease in GSH levels and SOD activity in the cavernosal tissues of the I/R group were also significantly reversed by quercetin treatment. Furthermore, observed distorted morphology with ruptured endothelial cells and vacuolization in the cytoplasm of cavernosal tissues of I/R no longer persisted in the quercetin-treated I/R group. Thus, our results suggested that treatment with quercetin may have some benefits in controlling I/R-induced tissue injury through its anti-inflammatory, anti-apoptotic, and antioxidant effects.

The effect of long-term oral tadalafil treatment on corpus cavernosum function in an experimental spinal cord transection rat model

The aim of this study was to investigate the pharmacological effects of long-term oral tadalafil treatment on the corpus cavernosum function in rats subjected to experimental spinal cord transection (SCT). Thirty young adult, male Sprague–Dawley rats were randomly divided into five groups (n¼ 6, each), as follows: (1) Control,(2) Control surgery (Sham), (3) Tadalafil (Td), (4) Experimental SCT, and (5) SCT + Tadalafil (SCT + Td). SCT rat model: after removal of T8-T9 spinal processes and laminates, a full-thickness scalpel incision was made in the spinal cord. SCT + Td rat model:rats subjected to SCT were given tadalafil (5mg kg(-1), p.o.) for 4 weeks. Next, the penile cavernous tissues obtained by en blocexcision were trimmed free of the surrounding tissue to isolate cavernosal smooth muscle strips, which were then transferred into the isolated organ baths to investigate isometric tension changes in response to various bioactive agents and electrical field stimulation (EFS). The relaxation response to acetylcholine at 0.01 mM concentration was significantly less in the SCT group compared with other groups. EFS-induced relaxation in the basal and precontracted cavernous tissue preparations was greater in the SCT + Td group than in the SCT group. This study demonstrated that long-term tadalafil administration preserves relaxation responses probably by affecting through the nitric oxide (NO)/cyclic guanosine monophosphate (cGMP) pathway in SCT-applied rats. This treatment strategy might preserve the erectile process and prevent the SCT-induced permanent damage in the cavernosal tissue.

Resveratrol, an activator of SIRT1, restores erectile function in streptozotocin-induced diabetic rats

The high incidence of erectile dysfunction (ED) in diabetes highlights a need for effective treatment strategies. Resveratrol, an activator of silent information regulator 2-related enzymes 1 (sirtuin1, SIRT1), has received attention for its valuable effects in cancer, neurodegenerative diseases, longevity and cardiovascular disease. To explore the effects of resveratrol in diabetes-induced ED, resveratrol was administered to rats with streptozocin (65mg kg(-1))-induced diabetes. Erectile function, cavernous structure, tissue protein expression of silent information regulator 2-related enzymes 1 (sirtuin1, SIRT1), p53 and forkhead transcription factor O 3a (FOXO3a), superoxide dismutase (SOD) activity and malondialdehyde (MDA) levels in the corpora cavernosa were studied. We found that SIRT1 was expressed in cavernosal tissue, and it was downregulated in the corpora of diabetic rats. The administration of resveratrol upregulated the expression of SIRT1 and restored erectile function. In contrast, resveratrol downregulated the expression of p53 and FOXO3a, which regulate apoptosis and oxidative stress. Furthermore, the resveratrol-treated group showed an improvement in smooth muscle content, SOD activity and MDA levels when compared with the diabetic group. Therefore, the ability of resveratrol to improve diabetes-induced ED is likely related to its activation of SIRT1 expression, thus causing the suppression of apoptosis and resistance towards oxidative stress.

The effect of diet-induced insulin resistance on DNA methylation of the androgen receptor promoter in the penile cavernosal smooth muscle of mice

Population studies have suggested an association between diabetes and the symptoms of testosterone deficiency. Recently, the expression of the androgen receptor (AR) has been shown to be decreased in diabetic patients. Furthermore, diabetes has been shown to induce global methylation. In this study, we used an animal model to investigate whether diabetes results in increased methylation of the AR promoter and whether these changes are associated with the decreased expression of AR in penile cavernosal smooth muscle tissue. Twenty C57BL/6J mice were divided into two groups, receiving either high- (mature diabetic) or low- (mature control) caloric meals for 14 weeks. Another 10 mice were killed at 1 week (young control). Animals in the mature diabetic group showed decreased testosterone levels, although this was not statistically significant. In both control groups, no significant methylation was observed in the AR promoter region CpG island (-85 to +339). In the mature diabetic group, significant methylation was observed at +185 and +200 of the AR promoter. These changes were associated with increased homeostatic model assessment for insulin resistance (HOMA-IR) and decreased corpus cavernosal tissue mass and expression of AR mRNA and protein. We conclude that in these animals, insulin resistance increased the methylation of the GC-rich regions of the AR promoter, leading to decreased AR expression.

Angiotensin II Increases Corpus Cavernosal Contractility and Oxidative Stress in Partial Bladder Outlet Obstructed Rabbits: Relevance to Erectile Dysfunction

We investigated the effect angiotensin II (Ang II), a corpus cavernosal smooth muscle (CCSM) constrictor peptide, has on tissue taken from rabbits following chronic partial bladder outlet obstruction (PBOO), as this model is characterized by an increase in corpus cavernosal collagen deposition and a marked reduction and impaired relaxation of CCSM cells. To determine the interaction between Ang II and nitric oxide (NO) and the development of oxidative stress (OS) in a rabbit model of chronic PBOO. Corpus cavernosal tissue was obtained from 12 sham-operated and 20 PBOO rabbits. Organ bath studies determined Ang II/NO interaction on CCSM function using losartan (AT1 receptor antagonist), sodium nitroprusside (SNP, NO donor), electrical field stimulation (EFS), and vardenafil (phosphodiesterase type 5 inhibitor). The role of OS in the Ang II response was also determined using diphenylene iodonium chloride (DPI), the nicotinamide adenine dinucleotide phosphate oxidase inhibitor, which inhibits superoxide production and superoxide dismutase (SOD, the enzyme that accelerates the breakdown of superoxide). Action of Ang II and AT1 receptor antagonist, as well as SOD and DPI on CCSM function. Ang II caused a dose-dependent contraction of CCSM strips that was enhanced in PBOO rabbits and inhibited by losartan, DPI, and SOD. CCSM relaxation induced by SNP/EFS was impaired in this model and improved by vardenafil and losartan. These findings imply that the increased Ang II contractile response is a pathological consequence of PBOO and that AT1 receptor inhibition may be a therapeutic approach to treat ED associated with PBOO.

Ca2+ -activated K+ channel (KCa) stimulation improves relaxant capacity of PDE5 inhibitors in human penile arteries and recovers the reduced efficacy of PDE5 inhibition in diabetic erectile dysfunction.

We have evaluated the influence of calcium-activated potassium channels (KCa ) activation on cGMP-mediated relaxation in human penile tissues from non-diabetic and diabetic patients, and on the effects of PDE5 inhibitors on erectile responses in control and diabetic rats. Cavernosal tissues were collected from organ donors and from patients with erectile dysfunction (ED). Relaxations of corpus cavernosum strips (HCC) and penile resistance arteries (HPRA) obtained from these specimens were evaluated. Intracavernosal pressure (ICP) increases to cavernosal nerve electrical stimulation were determined in anaesthetized diabetic and non-diabetic rats. Concentration-dependent vasodilation to the PDE5 inhibitor, sildenafil, in HPRA was sensitive to endothelium removal, NO/cGMP pathway inhibition and KCa blockade. Accordingly, activation of KCa with NS-8 (10 μM) significantly potentiated sildenafil-induced relaxations in HPRA (EC50 0.49 ± 0.22 vs. 5.21 ± 0.63 μM). In HCC, sildenafil-induced relaxation was unaffected by KCa blockade or activation. Potentiating effects in HPRA were reproduced with an alternative PDE5 inhibitor (tadalafil) and KCa activator (NS1619) and prevented by removing the endothelium. Large-conductance KCa (BK) and intermediate-conductance KCa (IK) contribute to NS-8-induced effects and were immunodetected in human and rat penile arteries. NS-8 potentiated sildenafil-induced enhancement of erectile responses in rats. Activation of KCa recovered the impaired relaxation to sildenafil in diabetic HPRA while sildenafil completely reversed diabetes-induced ED in rats only when combined with KCa activation. Activation of KCa improves vasodilatory capacity of PDE5 inhibitors in diabetic and non-diabetic HPRA, resulting in the recovery of erectile function in diabetic rats. These results suggest a therapeutic potential for KCa activation in diabetic ED.

814 SONIC HEDGEHOG REGULATES PENILE MORPHOLOGY IN PROSTATECTOMY AND DIABETIC PATIENTS

You have accessJournal of UrologySexual Function/Dysfunction/Andrology: Basic Research (I)1 Apr 2013814 SONIC HEDGEHOG REGULATES PENILE MORPHOLOGY IN PROSTATECTOMY AND DIABETIC PATIENTS Nicholas Angeloni, Christopher Bond, Kevin McVary, and Carol Podlasek Nicholas AngeloniNicholas Angeloni Chicago, IL More articles by this author , Christopher BondChristopher Bond Chicago, IL More articles by this author , Kevin McVaryKevin McVary Chicago, IL More articles by this author , and Carol PodlasekCarol Podlasek Chicago, IL More articles by this author View All Author Informationhttps://doi.org/10.1016/j.juro.2013.02.380AboutPDF ToolsAdd to favoritesDownload CitationsTrack CitationsPermissionsReprints ShareFacebookTwitterLinked InEmail INTRODUCTION AND OBJECTIVES Erectile dysfunction (ED) is a debilitating medical condition and current treatments are ineffective in patients with cavernous nerve (CN) injury, due to penile remodeling and apoptosis. Sonic hedgehog (SHH) is a critical regulator of penile smooth muscle and apoptosis that is decreased in rat prostatectomy and diabetic ED models. SHH inhibition in the penis induces apoptosis and ED, and SHH treatment at the time of CN injury suppresses smooth muscle apoptosis and promotes regeneration of erectile function. Thus SHH treatment has significant translational potential as an ED therapy if similar mechanisms underlie ED development in patients. In this study we quantify SHH protein and morphological changes in corpora cavernosal tissue of control, prostatectomy and diabetic patients and hypothesize that decreased SHH protein is an underlying cause of ED development in prostatectomy and diabetic patients. METHODS Human corpora cavernosal tissue was obtained from patients undergoing penile implant to treat ED in prostatectomy (n=21), diabetic (n=20) and Peyronie's (control, n=13) patients. Quantification of SHH protein was performed by Western analysis. SHH localization was examined by immunohistochemical analysis and insitu hybridization. Smooth muscle and apoptosis were quantified by Western analysis for α-ACTIN, trichrome and TUNEL. RESULTS Shh RNA was synthesized in corpora cavernosal smooth muscle and SHH protein was also active in smooth muscle, indicating autocrine signalling. Precursor and active SHH protein were significantly decreased 40% and 44% in prostatectomy and 40% and 39% in diabetic patients. Apoptosis was increased 23% in prostatectomy and 27% in diabetic patients and was observed primarily in corpora cavernosal smooth muscle. Trichrome stain showed decreased smooth muscle/collagen in prostatectomy and diabetic patients. This was confirmed by quantification of alpha-ACTIN/GAPDH, which decreased ∼ 50% in prostatectomy and diabetic patients. CONCLUSIONS Parallel morphological changes and decreased SHH protein were observed in animal models of ED and in ED patients that have had a prostatectomy or were diabetic. Since localized SHH treatment is effective in suppressing neuropathy-induced apoptosis and ED in rat models, SHH treatment has the potential to be similarly effective in prostatectomy and diabetic patients. The increased apoptotic index long after initial injury is suggestive of ongoing remodeling that may be manipulatable. © 2013 by American Urological Association Education and Research, Inc.FiguresReferencesRelatedDetails Volume 189Issue 4SApril 2013Page: e334-e335 Advertisement Copyright & Permissions© 2013 by American Urological Association Education and Research, Inc.MetricsAuthor Information Nicholas Angeloni Chicago, IL More articles by this author Christopher Bond Chicago, IL More articles by this author Kevin McVary Chicago, IL More articles by this author Carol Podlasek Chicago, IL More articles by this author Expand All Advertisement Advertisement PDF downloadLoading ...

Beneficial influence of topical extra virgin olive oil application on an experimental model of penile fracture in rats

Penile fracture (PF) is known as a traumatic rupture of the tunica albuginea of corpus cavernosum. In this study, we aimed to investigate the healing influence of topical extra virgin olive oil (EVOO) on PF through evaluating levels of some oxidative stress biomarkers for the first time. Histopathological evaluation was also realized. A total of 18 male Sprague-Dawley albino rats were divided into three groups of six rats each as control group, in PF (alone) group, and PF + EVOO group. Experimental PF was formed via incising from the proximal dorsal side of the penis in the rats of all groups except control. While in PF (alone) group, fracture was formed and the incision was primarily closed, in PF + EVOO group in addition to foregoing processes, EVOO was also administrated topically twice a day for 3 weeks. At the end of the experiment, all rats were killed and penectomy was carried out. While malondialdehyde, myeloperoxidase, lipid hyroperoxide, and total oxidant status significantly (p < 0.05) increased, reduced glutathione and total free sulfhydryl groups markedly (p < 0.05) decreased in PF (alone) group when compared with PF + EVOO group. Levels of these parameters were reversed to nearly normal values by topical EVOO application. Protection by EVOO is further substantiated via the improved histological findings in PF + EVOO group as against degenerative changes in the rats of PF (alone) group. Our data revealed that EVOO has protective effect in penile cavernosal tissue through probably its antioxidant, free radical defusing, anti-inflammatory, and antimicrobial effects.

Shockwave treatment of erectile dysfunction

Low-intensity extracorporeal shock wave therapy (LI-ESWT) is a novel modality that has recently been developed for treating erectile dysfunction (ED). Unlike other current treatment options for ED, all of which are palliative in nature, LI-ESWT is unique in that it aims to restore the erectile mechanism in order to enable natural or spontaneous erections. Results from basic science experiments have provided evidence that LI-ESWT induces cellular microtrauma, which in turn stimulates the release of angiogenic factors and the subsequent neovascularization of the treated tissue. Extracorporeal shock wave therapy (ESWT) has been clinically investigated and applied in several medical fields with various degrees of success. High-intensity shock wave therapy is used for lithotripsy because of its focused mechanical destructive nature, and medium-intensity shock waves have been shown to have anti-inflammatory properties and are used for treating a wide array of orthopedic conditions, such as non-union fractures, tendonitis, and bursitis. In contrast, LI-ESWT has angiogenetic properties and is therefore used in the management of chronic wounds, peripheral neuropathy, and in cardiac neovascularization. As a result of these characteristics we initiated a series of experiments evaluating the effect of LI-ESWT on the cavernosal tissue of patients with vasculogenic ED. The results of our studies, which also included a double-blind randomized control trial, confirm that LI-ESWT generates a significant clinical improvement of erectile function and a significant improvement in penile hemodynamics without any adverse effects. Although further extensive research is needed, LI-ESWT may create a new standard of care for men with vasculogenic ED.

Argirein alleviates corpus cavernosum dysfunction by suppressing pro-inflammatory factors p66Shc and ER stress chaperone Bip in diabetic rats

The aim was to investigate whether argirein, which releases rhein and L-arginine after medication, could improve erectile dysfunction (ED) in diabetic rats through normalising the abnormalities of nitric oxide synthase (NOS), p66Shc and immunoglobulin heavy-chain binding protein (Bip), in the corpus cavernosum (CC). SD rats were randomly divided into six groups. Except for the control group, rats were injected with streptozotocin (STZ) (60 mg/kg, i.p.) once. During weeks 5-8 following STZ injection, except for STZ-injected untreated rats, others were treated with aminoguanidine (AMG; 100 mg/kg/day, i.g.), or argirein at three doses (50, 100 and 200 mg/kg/day, i.g.). The vascular activity and biomarkers of the cavernosum were examined. Constrictive and dilative activity was abnormal in the CC, associated with decreased nitric oxide (NO) in serum in the diabetic (DM) group. Increased expression of p66Shc, Bip and inducible nitric oxide synthase (iNOS) and decreased endothelial nitric oxide synthase (eNOS) in the CC were significant in DM rats. Argirein and AMG improved these abnormities significantly. We concluded that vascular activity of the cavernosal tissue was impaired due to upregulated p66Shc and Bip in the diabetic CC. Argirein alleviates the vascular dysfunction of the CC by suppressing these upregulated pro-inflammatory proteins caused by diabetic lesions.

Erectile Function Is Improved in Aged Rats by PnTx2‐6, a Toxin from Phoneutria nigriventer Spider Venom

Age-associated erectile dysfunction (ED) involves a decrease in nitric oxide (NO) availability and impaired relaxation. PnTx2-6, a toxin from the Phoneutria nigriventer spider, has been demonstrated to improve erectile function via NO/cyclic guanosine monophosphate (cGMP) pathway. This spider's venom is characterized by several symptoms, including erection. PnTx2-6 has been implicated in this phenomenon. Animal venoms have been postulated as potential drugs to treat ED. PnTx2-6 toxin improves erectile function in aged rats via NO/cGMP. We investigated the effect of PnTx2-6 in the erectile function of aged rats. ED was evaluated through changes in intracavernosal pressure/mean arterial pressure ratio during electrical field stimulation (EFS) of the pelvic ganglion of aged and adult rats (70 vs. 14 weeks). In functional studies, EFS-induced relaxation of corpus cavernosum (CC) strips were performed with or without PnTx2-6 (10-8M). The decrease in erectile function associated with age was partially restored 15-20 minutes after injection of PnTx2-6 and further improved by sildenafil. PnTx2-6 enhanced EFS-induced relaxation, as well as cGMP levels in CC, from young and aged rats. Relaxation due to PnTx2-6 was further increased after 30 minutes incubation with Y-27632, a Rho-kinase inhibitor (10-6 M), in aging CC. Nitric oxide synthase (NOS) activity in aged and young cavernosal tissue was increased by incubation with PnTx2-6 (10 minutes). However, this toxin did not modify NOS expression. PnTx2-6 improves penile relaxation in aged rats, via increased NOS activity and NO release, resulting in enhanced cGMP levels.

Nitric Oxide May Mediate Nipple Erection

The nipple is a specialized structure that can become erect by cold, sexual arousal, breast-feeding, or other tactile stimulations, which can induce the milk ejection reflex and sexual arousal because of intense sensory innervation. The studies that have been conducted thus far to identify the mechanism of nipple erection (NE) are not sufficient. It has been stated that NE occurs via activation of the sympathetic nervous system and smooth muscle contraction. The purposes of this study were to investigate the existence of nitric oxide synthase (NOS) in the nipple-areola complex (NAC) to explain the NE mechanism. Considering that smooth muscle relaxation might be effective in NE, endothelial and neuronal NOS expression and localization were investigated via immunohistochemical methods on sagittal sections from 17 human NACs. The results of this study indicate that eNOS is expressed in the vascular endothelium, ductal epithelium, and smooth muscles, whereas nNOS is expressed in the neural fibers, smooth muscles, ductal epithelium, and vascular endothelium in the NAC. Sinusoidal spaces with endothelial layers similar to those found in penile cavernosal tissue are not found in the NAC. Various mediators are known to affect the function of the NAC smooth muscles; however, this study demonstrates that enzymes (eNOS and nNOS) that synthesize nitric oxide are expressed in the NAC.

Abstract 254: Treatment With Anti-TLR4 Antibody Lowers Blood Pressure and Improves Erectile Function in Doca-salt Rats

Inflammation and endothelial dysfunction play important roles in hypertension, disease associated with erectile dysfunction (ED). Growing evidence suggests that the immune system through activation of toll-like receptors (TLRs), such as TLR4, may contribute to this process. We hypothesized that chronic treatment with anti-TLR4 antibody improves erectile function in DOCA-salt hypertensive rats. Sprague-Dawley normotensive rats (Sham) and DOCA-salt (deoxycorticosterone acetate 200mg/kg, 6 weeks) hypertensive rats were treated with antibody anti-TLR4 (1ug/day, i.p.) or vehicle in the last 3 weeks. Erectile function was evaluated in vivo through measurements of changes in intracavernosal pressure/mean arterial pressure ratio (ICP/MAP) during electrical stimulation (EFS) of the major pelvic ganglion (MPG). Functional responses of cavernosal tissue were also performed. Anti-TLR4 treatment improved erectile function and significantly lowered blood pressure in DOCA-salt rats (Fig. *p&lt;0.05 DOCA treated vs. untreated). DOCA-salt rats exhibited increased maximal contractile response to phenylephrine (1.53±0.2 vs. 0.92±0.12mN) and EFS (1.36±0.14 vs. 0.88±0.11mN, respectively) compared to Sham, which was attenuated (20±1.3% to PE and 26.5±2% to EFS) by anti-TLR4 treatment. Furthermore, this treatment enhanced nitrergic relaxation (16Hz) in penile tissue from DOCA-salt rats (33±3% untreated vs. 52±4% treated, p&lt;0.05). In conclusion, these results suggest that TLR4 may mediate hypertension-associated ED.

Abstract 183: Hypertension Increases Toll-Like Receptor 2 (TLR2) and Inflammatory Cytokine Expression in the Corpus Cavernosum From Sprague Dawley Rats

Erectile dysfunction (ED) significantly reduces quality of life and is an early warning of cardiovascular disease. The prevalence of ED is higher among hypertensive compared to normotensive men. Activation of the immune system has been implicated in the development of hypertension; however, the role of the immune system in the development of ED remains unknown. In this study, we hypothesized that TLR2, a key player in innate immunity, is increased leading to an inflammatory response in the corpus cavernosum of hypertensive rats. We induced hypertension in male Sprague Dawley (SD) rats (age 15-weeks) via administration of N (G)-nitro-L-arginine methyl ester (L-NAME), a nitric oxide synthase inhibitor, for 4 weeks in drinking water (500mg/L). Our results showed that the mean systolic blood pressure from L-NAME treated rats was significantly greater (p&lt;0.05) compared to controls (208±33 vs 121±3mmHg). Western blot analysis demonstrated that protein expressions of TLR2, along with its primary intra-cellular signaling protein, myeloid differentiation primary response protein 88 (MyD88), were higher in the corpus cavernosum from L-NAME-treated rats compared to controls (1.691±0.2 vs 1.000±0.1) and (2.177±0.2 vs 1.000±0.3), respectively. Our results also showed that, there is an increase in the phosphorylation of the nuclear factor of kappa light polypeptide gene enhancer in B-cells inhibitor, alpha (IκBα) in the corpus cavernosum from L-NAME-treated rats compared to controls (2.038±0.2 vs 1.000±0.2). Additionally, the cavernosal tissue expression levels of the pro-inflammatory cytokine tumor necrosis factor-alpha (TNF-α) was also increased in the L-NAME-treated group compared to control (2.757±0.4 vs 1.000±0.3). Together, these data suggest that increased activation of TLR2 may initiate an inflammatory response which may lead to corpus cavernosum dysfunction, potentially contributing to ED in a rat model of hypertension induced via nitric oxide synthase inhibition.

800 NOVEL IN VITRO THREE DIMENTIONAL SCAFFOLDLESS MODEL OF CAVERNOUS TISSUE FOR STUDY OF DIABETIC ERECTILE DYSFUNCTION

You have accessJournal of UrologySexual Function/Dysfunction/Andrology: Basic Research I1 Apr 2012800 NOVEL IN VITRO THREE DIMENTIONAL SCAFFOLDLESS MODEL OF CAVERNOUS TISSUE FOR STUDY OF DIABETIC ERECTILE DYSFUNCTION Hazem Orabi and Tom Lue Hazem OrabiHazem Orabi Assiut, Egypt More articles by this author and Tom LueTom Lue San Francisco, CA More articles by this author View All Author Informationhttps://doi.org/10.1016/j.juro.2012.02.889AboutPDF ToolsAdd to favoritesDownload CitationsTrack CitationsPermissionsReprints ShareFacebookTwitterLinked InEmail INTRODUCTION AND OBJECTIVES Despite the overwhelming success of phosphodiesterase 5 inhibitors, the demand for new pharmacotherapeutic and cellular therapies for (erectile dysfunction) ED treatment continues to rise. The introduction of new therapies needs to be tested pre-clinically before applying these therapies on humans. The aim of this study is to develop a high-throughput model of corpus cavernosal sinusoidal tissue that can be used to screen potential drugs, and cell therapies for treatment of ED and to test the effects of hyperglycemic state (mimicking Diabetic ED) against normal glucose level. METHODS Using biopsies of human penile tissues, human cavernous smooth muscle (HCSMC) and endothelial cells (ECs were separately isolated and expanded. The phenotype of HCSMC and ECs were verified with regular microscopy, IHC (immnuohistochemistry) using smooth muscle actin (SMA), calponin, and smooth muscle myosin (SM myosin) for HCSMC and vWF and CD31 for ECs. Additionally, LDL uptake and Matrigel Tube formation assay were used for ECs phenotype verification. Cavernous sinusoidal tissue was formed in vitro by seeding HCSMC followed by ECs. The cavernous tissue was harvested at different time periods and collected for histology. The histological assessment included H&E, Masson Trichrome and IHC for SMC, ECs, collagen and apoptosis. The cavernous sinusoidal tissue was subjected to a state of hyperglycemia and tissue was collected for analysis for SMC, collagen, and ECs pathology for receptor of advanced glycation end products (RAGE) in comparison for normal glucose state. RESULTS The microscopy and IHC were positive staining for HCSMC and ECs markers. The cavernous tissue was detached intact in consistent manner. The biochemical staining and IHC showed it is formed of upper layer of ECs and multiple layers of HCSMC separated by a basement membrane composed of mainly of collagen. This structure was maintained over a period of one week with minimal apoptosis. After the exposure to hyperglycemia, there was loss of ECs, increase collagen content and HCSMC apoptosis. There was also increased expression of RAGE as a mechanism of diabetic ED. CONCLUSIONS Our results showed that our in vitro 3D model of corpus cavernosal sinusoidal is appropriate for study of cavernous tissue and its diseases and test new drugs and therapies for ED. It is reproducible, reliable and provided at low cost. Our in vitro model of hyperglycemia is mimicking diabetic ED with its pathologic effects and mechanisms. © 2012 by American Urological Association Education and Research, Inc.FiguresReferencesRelatedDetails Volume 187Issue 4SApril 2012Page: e327 Advertisement Copyright & Permissions© 2012 by American Urological Association Education and Research, Inc.MetricsAuthor Information Hazem Orabi Assiut, Egypt More articles by this author Tom Lue San Francisco, CA More articles by this author Expand All Advertisement Advertisement PDF downloadLoading ...

Impaired cavernosal relaxation in Angiotensin‐ II infused mice is improved by deletion of Toll like receptor 4 (TLR4)

TLRs are important contributors of the innate immune system. TLR‐mediated signaling is involved in inflammatory responses and TLR4 has been associated with cardiovascular diseases (CVD). Erectile dysfunction (ED) is an early marker for CVD. Upregulation of angiotensin II (Ang‐II) is linked with CDV and ED. Ang II is found in human corpus cavernosum (CC) and abnormal levels induce vasoconstriction and endothelial dysfunction. We hypothesize that deletion of TLR4 contributes to improve mice cavernosal relaxation impaired due to Ang‐II infusion. TLR4 knockout (KO) mice and wild type (WT) were infused with Ang II (42 ng/min) for 2 weeks. Functional responses of cavernosal tissue were performed. Cavernosal strips from Ang II WT mice exhibited increased contraction to phenylephrine (PE, 10−8 to 10−4M) and electrical field stimulation (EFS, 1–32 Hz) compared to WT control (CTL), which is attenuated around 25 ± 4.5 % in Ang II TLR4 KO compared to Ang II WT mice. Impaired endothelium‐dependent relaxation to acetylcholine (Ach, 10−9 to 10−5M) in CC from Ang II was improved almost 20 ± 3.7% compared to Ang II TLR KO mice. Furthermore, TLR4 deletion enhanced nitrergic‐induced relaxation in penile tissue from Ang‐II infused mice. In conclusion, these results suggest that TLR4 contributes to impaired penile relaxation and contraction in response to pathological stimulation such as upregulation of Ang‐ II.Financial support: NIH, AHA.

Endovascular Therapy for Vasculogenic Erectile Dysfunction

Erectile dysfunction (ED) is an important clinical condition that affects a significant proportion of men. Although there are many etiologies for ED, many cases have a vascular basis that is related to inadequate arterial inflow, veno-occlusive dysfunction, or abnormalities in smooth muscle (cavernosal tissue) relaxation. These vascular abnormalities can exist in isolation or combination. Since the advent of phosphodiesterase-5 inhibitor (PDE5i) therapy, the initial management of ED in most cases consists of a brief medical evaluation followed by a trial of PDE5i therapy. However, up to 50% of men have an inadequate response to PDE5i therapy and discontinue therapy. Subsequent therapies for ED are increasingly invasive, including penile injection of vasodilators, vacuum pumps, and penile implants. With increased awareness of ED among clinicians and the growing mechanistic link between ED and atherosclerotic vascular disease, there has been renewed interest in the diagnosis and management of arteriogenic ED. Prior reports in the 1980s described the existence of arterial inflow lesions in patients with ED, and there are a modest number of reports describing the feasibility of revascularization with balloon angioplasty. Despite initial clinical success, enthusiasm for this technique waned, presumably because ED frequently recurred due to restenosis and lack of small vessel endovascular therapies. Recent investigation and the availability of newer tools such as drug-eluting stents have renewed interest in this field. Although conceptually attractive, endovascular therapy for ED presents significant challenges related to unanswered questions such as the prevalence and appropriate diagnostic evaluation of arteriogenic ED, and the safety and feasibility of stent-based therapies in this population. In addition, the evaluation, management, and follow-up of patients with vascular ED require a multi-disciplinary team with specialists in urology, sexual medicine, and vascular medicine. Despite these challenges, the potential for endovascular treatment of these patients remains one of the most exciting areas of investigation in vascular medicine.

Separation, culture and identification of SD rat corpus cavernosal endothelial cells

The aim of the study is to investigate the methods of separation, culture and identification of Sprague Dawley (SD) rat corpus cavernosal vascular endothelial cells (CCECs). Cavernosal tissues were isolated from male SD rats. Enzymatic digestion was applied to separate CCECs. Purified cells were obtained using immunomagnetic beads and flow cytometric cell sorting and subcultured in EMG-2 medium. The growth curve of CCECs was measured by the tetrazolium salt 3-[4,5-dimethylthiazol-2-yl]-2,5-diphenyltetrazolium bromide assay. The cells were identified by von Willebrand factor (vWF) using immunofluorescence, and the positive percentage of vWF expression was detected by flow cytometry. The monomorphic cobblestone-like cells were observed by microscopy. High purification was obtained using immunomagnetic beads. After 2 days of incubation, cells entered the logarithmic growth phase and reached a plateau on the fifth day. The vWF expression in cytoplasm was positive. The purity of cells was 95.8%, which was tested by flow cytometry. SD rat CCECs can be separated and cultured successfully by the method of enzymatic digestion, immunomagnetic beads and flow cytometric cell sorting.

473 Increased expression of oxidative stress markers in human diabetic cavernosal tissue

473 Increased expression of oxidative stress markers in human diabetic cavernosal tissue

Adipose tissue-derived stem cell-seeded small intestinal submucosa for tunica albuginea grafting and reconstruction

Porcine small intestinal submucosa (SIS) has been widely used in tunica albuginea (TA) reconstructive surgery. Adipose tissue-derived stem cells (ADSCs) can repair damaged tissue, augment cellular differentiation, and stimulate release of multiple growth factors. The aim of this rat study was to assess the feasibility of seeding ADSCs onto SIS grafts for TA reconstruction. Here, we demonstrate that seeding syngeneic ADSCs onto SIS grafts (SIS-ADSC) resulted in significant cavernosal tissue preservation and maintained erectile responses, similar to controls, in a rat model of bilateral incision of TA, compared with sham-operated animals and rats grafted with SIS graft (SIS) alone. In addition to increased TGF-β1 and FGF-2 expression levels, cross-sectional studies of the rat penis with SIS and SIS-ADSC revealed mild to moderate fibrosis and an increase of 30% and 40% in mean diameter in flaccid and erectile states, respectively. SIS grafting induced transcriptional up-regulation of iNOS and down-regulation of endothelial NOS, neuronal NOS, and VEGF, an effect that was restored by seeding ADCSs on the SIS graft. Taken together, these data show that rats undergoing TA incision with autologous SIS-ADSC grafts maintained better erectile function compared with animals grafted with SIS alone. This study suggests that SIS-ADSC grafting can be successfully used for TA reconstruction procedures and can restore erectile function.