Maximal Intracavernous Pressure Research Articles

Epigallocatechin-3-gallate ameliorates erectile function in aged rats via regulation of PRMT1/DDAH/ADMA/NOS metabolism pathway.

Aging-related ED is predominantly attributed to neurovascular dysfunction mediated by NO suppression and increased oxidative stress in penis. The alterations of protein arginine methyltransferases 1 (PRMT1)/dimethylarginine dimethylaminohydrolase (DDAH)/asymmetrical dimethylarginine (ADMA)/NO synthase (NOS) pathway regulate NO production in the vascular endothelium. Epigallocatechin-3-gallate (EGCG) is one of the most abundant and antioxidative ingredients isolated from green tea. In the present study, 40 Sprague-Dawley rats were randomly distributed into four groups: one young rat group and three aged rat groups treated with daily gavage feedings of EGCG at doses of 0, 10 mg kg−1, and 100 mg kg−1 for 12 weeks, respectively. Erectile function was assessed by electrical stimulation of the cavernous nerves with intracavernous pressure (ICP) measurement. After euthanasia, penile tissue was investigated using Western blot and ELISA to assess the PRMT1/DDAH/ADMA/NOS metabolism pathway. Superoxide dismutase (SOD) and malondialdehyde (MDA) levels were detected by colorimetry. We also evaluated smooth muscle contents. The ratio of maximal ICP and mean systemic arterial pressure (MAP) was markedly higher in EGCG-treated aged rats than in untreated aged rats. We found that DDAH1 and DDAH2 were expressed in cavernosal tissue, and they were downregulated in corpora of aged rats. The administration of EGCG upregulated the expression and activity of DDAH. In contrast, EGCG treatment downregulated the expression of PRMT1 and ADMA content. Moreover, EGCG-treated rats showed an improvement in smooth muscle expression, the ratio of smooth muscle cell/collagen fibril, SOD activity, and MDA levels when compared with untreated aged rats.

Involvement of Rho-Kinase/LIM Kinase/Cofilin Signaling Pathway in Corporal Fibrosis after Cavernous Nerve Injury in Male Rats.

The molecular mechanism of corporal fibrosis leading to erectile dysfunction (ED) following cavernous nerve (CN) injury is poorly understood. To determine whether the LIMK2/cofilin pathway, the downstream effectors of ROCK1, was involved in ED and corporal fibrosis following bilateral CN injury in male rats. Forty-eight 10-week-old male Sprague-Dawley rats were equally divided into three groups: sham surgery (S); bilateral CN crush injury (I); and bilateral CN resection (R). Within each groups, two subgroups were analyzed at 1 and 4 weeks postoperatively. Electrostimulation was performed to assess erectile function by the ratio of maximal intracavernous pressure to mean arterial pressure (ICP/MAP) and areas under the ICP curve to MAP (AUC/MAP). Penile tissue was processed for Masson's trichrome staining, Western blot (ROCK1, total LIMK2, phospho-LIMK2, total cofilin, phospho-cofilin), immunohistochemistry (alpha-SM actin [α-SMA]), and double immunofluorescent staining (ROCK1, phospho-LIMK2, vimentin). At each time point, both I and R groups showed a significantly lower percent of ICP/MAP and AUC, and decreased SM cell/collagen ratio and expression of α-SMA than S group. Densitometry revealed a significantly higher expression of ROCK1 in I and R groups compared with S group at all time points. The LIMK2 phosphorylation in I and R groups significantly increased at 1 week, but not at 4 weeks. The cofilin phosphorylation in R group significantly increased to that in S group starting at 1 week, while that in I group was increased significantly at 4 weeks. The double immunofluorescent staining noted that coexpression of vimentin with ROCK1 or phospho-LIMK2 in I and R groups was significantly increased mainly in the subtunical area at 1 week but not at 4 weeks. The ROCK1/LIMK2/cofilin pathway may be involved in ED related to corporal fibrosis, and it appears to be functional particularly in the early period after CN injury.

Comparative study of autologous stromal vascular fraction and adipose-derived stem cells for erectile function recovery in a rat model of cavernous nerve injury.

The abilities of intracavernous injection of autologous stromal vascular fraction (SVF) and adipose-derived stem cells (ADSCs) to facilitate recovery of erectile function in a rat model of cavernous nerve (CN) injury were compared. Forty male Sprague-Dawley rats were randomly divided into four groups: sham and control groups (intracavernous injection of phosphate-buffered saline), SVF group (intracavernous injection of SVF), and ADSC group (intracavernous injection of ADSCs). Rats in the latter three groups underwent bilateral CN injury prior to injection. The evaluation of erectile function and histomorphometric studies were performed 4 weeks after injection. The ratio of maximal intracavernous pressure to mean arterial pressure was significantly lower in the control group than in the sham group (0.18 vs. 0.56, p < .001). Intracavernous injection of SVF (0.36, p = .035) significantly improved erectile function compared with that in the control group, whereas the ADSC group (0.35, p = .052) showed marginally significant improvement. The smooth muscle/collagen ratio, smooth muscle content, number of neuronal nitric-oxide synthase-positive nerve fibers, and expression of von Willebrand factor were significantly higher in the SVF and ADSC groups than in the control group. Expression of endothelial nitric-oxide synthase was significantly increased in the SVF group. The increases in the smooth muscle/collagen ratio and von Willebrand factor expression were larger in the SVF group than in the ADSC group. Intracavernous injection of SVF or ADSCs was equally effective in recovering penile erection in a rat model of CN injury.

Role of oxidative stress in surgical cavernous nerve injury in a rat model.

This study investigates the role of oxidative stress in surgical cavernous nerve (CN) injury in a rat model. Eighty-four male Sprague-Dawley rats were randomly divided into three groups: group 1, sham-operated rats; group 2, bilateral CN-crushed rats; and group 3, bilateral CN-transection-and-sutured-immediately rats. Oxidative stress was evaluated by malondialdehyde levels, super oxide dismutase (SOD) activities, and glutathione peroxidase (GPX) activities in serum. Erectile function was assessed by CN electrostimulation at 3 months with mean maximal intracavernous pressure (ICP) and maximal ICP per mean arterial pressure. Nerve injury was assessed by toluidine blue staining of CNs and nicotinamide adenine dinucleotide phosphate (NADPH)-diaphorase staining of penile tissue. GPX protein expression and nitrotyrosine-3 (NT-3) levels in penile tissue were measured. Erectile function and the number of myelinated axons of CNs and NADPH-diaphorase-positive nerve fibers were statistically decreased between groups, from sham to crush to transection. For markers, both nerve-injury groups showed increased oxidative stress markers at early time points, with the transection group showing greater oxidative stress than the crushed group and values normalizing to sham levels by week 12. GPX expression and NT-3 levels in penile tissue were in concordance with the results of SOD and GPX. These results show that oxidative stress plays an important role in injured CNs, and different methods of CN injury can lead to different degrees of oxidative stress in a rat model.

Recombinant PAI-1 therapy restores myoendothelial junctions and erectile function in PAI-1-deficient mice.

Myoendothelial junctions are specialised projections of cell : cell contact through the internal elastic lamina between endothelial cells and vascular smooth muscle cells. These junctions allow for endothelial cells and vascular smooth muscle cells to make direct membrane apposition and are involved in cell : cell communication. In this study, we evaluated for the presence of myoendothelial junctions in murine corporal tissue and used plasminogen activator inhibitor (PAI)-1-deficient mice, which lack myoendothelial junctions, to determine whether myoendothelial junctions affect erectile function. Transmission electron microscopy demonstrated the presence of myoendothelial junctions in the corporal tissue of wild-type mice and confirmed the decreased junction numbers in the tissue of PAI-1(-/-) mice. A potential role for myoendothelial junctions in tumescence was established; in that, PAI-1(-/-) mice demonstrated a significantly longer time to achieve maximal intracavernous pressure. Treatment of PAI-1(-/-) mice with recombinant PAI-1 restored the number of myoendothelial junctions in the corporal tissue and also induced a significant decrease in time to maximal corporal pressures. Myoendothelial junctions were similarly identified in the human corporal tissue. These results suggest a critical role for myoendothelial junctions in erectile pathophysiology and therapies aimed at restoring myoendothelial junction numbers in the corporal tissue may provide a novel therapy for erectile dysfunction.

Neurturin enhances the recovery of erectile function following bilateral cavernous nerve crush injury in the rat

BackgroundThe molecular mechanisms responsible for the survival and preservation of function for adult parasympathetic ganglion neurons following injury remain incompletely understood. However, advances in the neurobiology of growth factors, neural development, and prevention of cell death have led to a surge of clinical interest for protective and regenerative neuromodulatory strategies, as surgical therapies for prostate, bladder, and colorectal cancers often result in neuronal axotomy and debilitating loss of sexual function or continence. In vitro studies have identified neurturin, a glial cell line-derived neurotrophic factor, as a neuromodulator for pelvic cholinergic neurons. We present the first in vivo report of the effects of neurturin upon the recovery of erectile function following bilateral cavernous nerve crush injury in the rat.MethodsIn these experiments, groups (n = 8 each) consisted of uninjured controls and animals treated with injection of albumin (blinded crush control group), extended release neurotrophin-4 or neurturin to the site of cavernous nerve crush injury (100 μg per animal). After 5 weeks, recovery of erectile function (treatment effect) was assessed by cavernous nerve electrostimulation and peak aortic pressures were measured. Investigators were unblinded to specific treatments after statistical analyses were completed.ResultsErectile dysfunction was not observed in the sham group (mean maximal intracavernous pressure [ICP] increase of 117.5 ± 7.3 cmH2O), whereas nerve injury and albumin treatment (control) produced a significant reduction in ICP elevation of 40.0 ± 6.3 cmH2O. Neurturin facilitated the preservation of erectile function, with an ICP increase of 55% at 62.0 ± 9.2 cmH2O (p < 0.05 vs control). Extended release neurotrophin-4 did not significantly enhance recovery of erectile function with an ICP change of 46.9 ± 9.6. Peak aortic blood pressures did not differ between groups. No significant pre- and post-treatment weight differences were observed between control, neurotrophin-4 and neurturin cohorts. All animals tolerated the five-week treatment course.ConclusionTreatment with neurturin at the site of cavernous nerve crush injury facilitates recovery of erectile function. Results support further investigation of neurturin as a neuroprotective and/or neuroregenerative agent facilitating functional recovery after cavernous or other pelvic autonomic nerve injuries.

MP47-15 ADIPOSE-DERIVED STEM CELLS IMPROVE ERECTILE FUNCTION THROUGH SECRETION OF INSULIN-LIKE GROWTH FACTOR-1 AND VASCULAR ENDOTHELIAL GROWTH FACTOR IN AGED RAT

INTRODUCTION AND OBJECTIVES: Adipsoe-derived stem cells (ADSCs) have been recently considered promising therapy for erectile dysfunction (ED). However, the mechanism of ADSCsbased therapy remains to be elucidated. The aim of this study was to determine whether transplantation of ADSCs was capable of resolving aging-related ED, and to investigate its underlying mechanisms. METHODS: Insulin-like growth factor-1 (IGF-1) and vascular endothelial growth factor (VEGF) secreted by ADSCs were assessed in vitro. Sixteen 24-month-old male Sprague-Dawley rats were used for comparative analysis of 2-week treatment regiments with CM-DiI labeled ADSCs or PBS. Eight additional 5-month-old rats were used as young rats group. At 2-week post-transplantation, all the rats were analyzed for erectile function, cavernous IGF-1 and VEGF levels, and penile histology. The IGF-1 and VEGF levels of ADSCs-conditioned medium and penile tissues were determined by an enzyme-linked immunosorbent assay (ELISA). The ratio of maximal intracavernous pressure (ICP) to mean arterial blood pressure (MAP) was measured to evaluate erectile function. Immunofluorescence staining was used to evaluate the number of ADSCs, and the contents of cavernous smooth muscle and endothelium. RESULTS: ADSCs could secrete a large amount of IGF-1 and VEGF in culture medium compared to basal medium (P<0.05). Compared to the young rats, the untreated aged rats showed significantly lower Max ICP/MAP (P<0.05) and ADSCs treatment significantly increased the ratio (P<0.05). Immunofluorescence staining demonstrated that there was only a small number of CM-DiI labeled ADSCs found in corpus cavernosum. The corpus cavernosum of untreated aged rats showed decreased IGF-1 and VEGF levels, and the contents of cavernous smooth muscle and endothelium compared to young rats (P<0.05). ADSCs treatment partially normalized these alterations (P<0.05). CONCLUSIONS: ADSCs treatment may improve aging-related ED partially through secretion of IGF-1 and VEGF.

MP43-18 EARLY REGULAR TREATMENT WITH A CANNABINOID 2 RECEPTOR AGONIST PROTECTED ERECTILE FUNCTION IN A RAT MODEL OF CAVERNOUS NERVE CRUSH INJURY

You have accessJournal of UrologySexual Function/Dysfunction/Andrology: Basic Research I1 Apr 2014MP43-18 EARLY REGULAR TREATMENT WITH A CANNABINOID 2 RECEPTOR AGONIST PROTECTED ERECTILE FUNCTION IN A RAT MODEL OF CAVERNOUS NERVE CRUSH INJURY Ettore Di Trapani, Colicchia Michele, Alberto Briganti, Manuela Tutolo, Niccolò Maria Passoni, Francesco Montorsi, Fabio Benigni, and Petter Hedlund Ettore Di TrapaniEttore Di Trapani More articles by this author , Colicchia MicheleColicchia Michele More articles by this author , Alberto BrigantiAlberto Briganti More articles by this author , Manuela TutoloManuela Tutolo More articles by this author , Niccolò Maria PassoniNiccolò Maria Passoni More articles by this author , Francesco MontorsiFrancesco Montorsi More articles by this author , Fabio BenigniFabio Benigni More articles by this author , and Petter HedlundPetter Hedlund More articles by this author View All Author Informationhttps://doi.org/10.1016/j.juro.2014.02.1175AboutPDF ToolsAdd to favoritesDownload CitationsTrack CitationsPermissionsReprints ShareFacebookTwitterLinked InEmail Introduction and Objectives Despite the introduction of nerve-sparing radical prostatectomy (NSRP), erectile dysfunction (ED) is a common and challenging sequele. The ED in NSRP is caused by neurapraxia that causes penile hypoxia, loss of nerves, smooth muscle fibrosis and veno-occlusive dysfunction. Recent studies reported immunomodulatory and antifibrotic activity of cannabinoids. We aimed to test the effect of a cannabinoid-2 receptor agonist in a rat model for pelvic neurapraxia Methods After ethical approval, Sprague Dawley rats (n=30, 250-300 g) were A) sham-operated (n=10); or subjected to bilateral cavernous-nerve (CN) crush injury (CNI) and B) treated with JWH-133 (1mg/kg, intraperitoneal, N=12), or C) vehicle (intraperitoneal, N=12). Treatment was initiated 3 days before surgery until 7 days thereafter. Mean arterial blood pressure (MAP) was measured by catheterizing carotid artery and erectile function by direct measurements of intracavernous pressure (ICP) during electrical stimulation (2, 4 and 6V) of the CN. Statistical analysis was performed using an ANOVA (Newman Keuls). Values are mean±SEM. Results Basal ICP was similar in the 3 groups and amounted to 16±2.2, 22±3.2, and 18±1.8cmH2O for sham, CNI + vehicle, and CNI + JWH-133, respectively. MAP amounted to 133±8 (sham), 137±8 (CNI + vehicle), and 125±9cmH2O (CNI+JWH-133). Vehicle treated rats with CNI exhibited at any stimulation parameter significantly lower erectile responses recorded as ICP/MAP than both sham and CNI rats treated with JWH-133. The ICP/MAP values for 2, 4, and 6V were 34.4±4.2, 42.3±4.7, and 46.3±5.4 for vehicle treated CNI rats (p<0.05 vs sham and JWH-133). Corresponding data for sham were 62.5±5, 70±4.3, and 75.1±7.1. ICP/MAP in CNI JWH-133 treated rats were not different from sham and amounted to 51.4±5.4, 74.6±10, and 87.2±11.8cmH2O/second. Corresponding AUC values for CNI rats treated with vehicle were lower (p<0.01-0.05) and amounted to 10.5±1.9, 14.6±1.9, and 17.9±2.5cmH2O/second. CNI rats treated with JWH-133 also exhibited lower AUC than sham (p<0.05) with values amounting to 19±5.4, 31.4±6, and 34±4.8cmH2O/second. At 4 and 6V, the AUC values of JWH-133-treated CNI rats were higher (p<0.05) than those of vehicle-treated CNI rats. Conclusions Early initiated perioperative regular treatment for 10 days with the CB2 agonist JWH-133 restored maximal ICP during erections in rats with CNI but only partially improved the total erectile responses recorded as the AUC. © 2014FiguresReferencesRelatedDetails Volume 191Issue 4SApril 2014Page: e484-e485 Advertisement Copyright & Permissions© 2014MetricsAuthor Information Ettore Di Trapani More articles by this author Colicchia Michele More articles by this author Alberto Briganti More articles by this author Manuela Tutolo More articles by this author Niccolò Maria Passoni More articles by this author Francesco Montorsi More articles by this author Fabio Benigni More articles by this author Petter Hedlund More articles by this author Expand All Advertisement Advertisement PDF downloadLoading ...

A Proteomic Analysis Using an Animal Model for Hyperlipidemia-related Erectile Dysfunction

To investigate the pathogenesis of hyperlipidemia-related erectile dysfunction and the effects of DA-8159, a new phosphodiesterase-5 inhibitor, on protein expression, we performed a proteomic analysis of differentially expressed proteins in the corpus cavernosum of hyperlipidemic rats by two-dimensional electrophoresis-mass spectrometry. Rats were fed high-cholesterol diet and treated with 5 mg·kg(-1)·day(-1) DA-8159 concurrently. After 5 months apparent hyperlipidemia and significantly decreased maximal intra-cavernous pressure were observed in the control group with the alteration of 8 proteins, which were restored by DA-8159 treatment. The proteins whose levels decreased >2-fold and attenuated by DA-8159 were determined alcohol dehydrogenase, aldolase A, annexin 1, and tropomyosin-rat, whereas proteins increased>2-fold and recovered by DA-8159 were found to be aldehyde dehydrogenase complex, guanine deaminase, creatine kinase-B, and phosphoglycerate mutase type B subunit.

The Selectivity and Potency of the New PDE5 Inhibitor TPN729MA

TPN729MA is a newly developed phosphodiesterase type 5 inhibitor (PDE5i) for the treatment of erectile dysfunction, which offers potential for greater selectivity and longer duration of action than PDE5i in current clinical use. We investigated the in vitro inhibitory potency and selectivity of TPN729MA on PDE isozymes, and its efficacy in animal models. The inhibition of 11 human recombinant PDEs by TPN729MA, sildenafil, and tadalafil were determined using radioimmunoassay. The effect of TPN729MA and sildenafil on intracavernous pressure (ICP), blood pressure (BP), and ICP/BP ratio were determined in a rat model of erection induced by electric stimulation and in a dog model of erection induced by sodium nitroprusside injection. The main outcome measures were IC50 of TPN729MA, sildenafil, and tadalafil for PDE1-PDE11; maximum ICP; BP and ICP/BP ratio. The IC50 of TPN729MA, sildenafil, and tadalafil for PDE5 was 2.28, 5.22, and 2.35 nM, respectively. TPN729MA showed 248, 366, 20, and 2671-fold selectivity against PDE1, PDE4, PDE6, and PDE11, respectively. TPN729MA showed excellent selectivity against PDE2, 3, 7, 8, 9, and 10 (>10,000-fold). In the rat model of erection, TPN729MA (5.0 and 2.5 mg/kg), but not sildenafil, significantly increased the maximum ICP compared with vehicle. Significantly increased ICP/BP was observed in the TPN729MA (5.0 mg/kg) group at all time points, in the TPN729MA (2.5 mg/kg) group at 75, 90, 105, and 120 minutes time points, and in sildenafil group at 75 and 90 minutes time points compared with vehicle. In the dog model of erection, TPN729MA and sildenafil significantly increased ICP and ICP/BP but showed no significant effect on BP compared with vehicle. TPN729MA is a potent PDE5i with a balanced selectivity profile. TPN729MA shows excellent in vitro and in vivo potency, and a longer effect on erectile function than sildenafil in animal model.

1023 INVOLVEMENT OF RHO-KINASE/LIM-KINASE/COFILIN SIGNALING PATHWAY IN ERECTILE DYSFUNCTION AND CORPORAL FIBROSIS AFTER CAVERNOUS NERVE INJURY IN MALE RATS

You have accessJournal of UrologySexual Function/Dysfunction/Andrology: Basic Research (II)1 Apr 20131023 INVOLVEMENT OF RHO-KINASE/LIM-KINASE/COFILIN SIGNALING PATHWAY IN ERECTILE DYSFUNCTION AND CORPORAL FIBROSIS AFTER CAVERNOUS NERVE INJURY IN MALE RATS Min Chul Cho, Sang Hoon Song, Sung Yong Cho, Kwanjin Park, Soo Woong Kim, and Jae-Seung Paick Min Chul ChoMin Chul Cho Goyang, Korea, Republic of More articles by this author , Sang Hoon SongSang Hoon Song Seoul, Korea, Republic of More articles by this author , Sung Yong ChoSung Yong Cho Seoul, Korea, Republic of More articles by this author , Kwanjin ParkKwanjin Park Seoul, Korea, Republic of More articles by this author , Soo Woong KimSoo Woong Kim Seoul, Korea, Republic of More articles by this author , and Jae-Seung PaickJae-Seung Paick Seoul, Korea, Republic of More articles by this author View All Author Informationhttps://doi.org/10.1016/j.juro.2013.02.608AboutPDF ToolsAdd to favoritesDownload CitationsTrack CitationsPermissionsReprints ShareFacebookTwitterLinked InEmail INTRODUCTION AND OBJECTIVES Molecular mechanism of corporal fibrosis leading to erectile dysfunction (ED) after cavernous nerve (CN) injury is poorly understood. Recently, we demonstrated that sphingosine-1-phosphate/RhoA/ROCK1 pathway could be involved in corporal fibrosis after CN injury. Activation of ROCK1 is followed by activation of downstream target kinases, LIM-kinase2 (LIMK2) and cofilin, resulting in fibroblast-to-myofibroblast differentiation, a pathophysiologic feature of fibrosis. Thus, the aim of this study was to determine whether LIMK2/cofilin pathway, the downstream effector of ROCK1, was involved in ED and corporal fibrosis after CN injury in male rats. METHODS Forty eight 10-week-old male Sprague-Dawley rats were equally divided into 3 groups: sham surgery (S); bilateral CN crush injury (I); and bilateral CN resection (R). Within each of 3 groups, two subgroups were analyzed as a function of time (1 and 4 weeks postoperatively). At 1 and 4 weeks postoperatively, electrostimulation was performed to assess erectile function by maximal intracavernous pressure (ICP)/mean arterial pressure (MAP) ratio and areas under the curve (AUC). Western blot (ROCK1, phospho/total LIMK2, phospho/total cofilin), immunohistochemistry (α-SMA and phospho-LIMK2) and Masson's trichrome staining were performed. RESULTS At each time point, both I and R groups showed significantly lower ICP/MAP ratio and AUC than S group. Mean ICP/MAP and AUC showed a trend toward higher level in I group than R group, which was not significantly different. At all time points, I and R groups had a significantly decreased SM cell/collagen ratio and expression of α-SMA compared to the S group and a trend toward decreasing over the study period. On immunohistochemical staining, the LIMK2 expression in both I and R groups was significantly higher than that in S group at 1 week, but not at 4 weeks. Densitometry revealed a significantly higher expression of ROCK1 in I and R group compared to S group at 1 and 4 weeks. The ratio of phospho/total LIMK2 protein expression in I and R groups was significantly decreased at 1 week, but not significantly different from that in S group at 4 weeks. The ratio of phospho/total cofilin protein expression in R group significantly decreased starting from 1 week, while that in I group significantly decreased as late as 4 weeks. CONCLUSIONS Our data suggest that LIMK2/cofilin pathway can be involved in ED and corporal fibrosis associated with loss of SM after CN injury, and appears to be functional particularly in the early phase after CN injury. © 2013 by American Urological Association Education and Research, Inc.FiguresReferencesRelatedDetails Volume 189Issue 4SApril 2013Page: e419-e420 Advertisement Copyright & Permissions© 2013 by American Urological Association Education and Research, Inc.MetricsAuthor Information Min Chul Cho Goyang, Korea, Republic of More articles by this author Sang Hoon Song Seoul, Korea, Republic of More articles by this author Sung Yong Cho Seoul, Korea, Republic of More articles by this author Kwanjin Park Seoul, Korea, Republic of More articles by this author Soo Woong Kim Seoul, Korea, Republic of More articles by this author Jae-Seung Paick Seoul, Korea, Republic of More articles by this author Expand All Advertisement Advertisement PDF downloadLoading ...

1029 IDENTIFICATION OF MICRORNA EXPRESSION PROFILE IN DIABETIC RATS' PENILE TISSUES AND POTENTIAL ROLE OF MIR-92A IN ERECTILE DYSFUNCTION

You have accessJournal of UrologySexual Function/Dysfunction/Andrology: Basic Research (II)1 Apr 20131029 IDENTIFICATION OF MICRORNA EXPRESSION PROFILE IN DIABETIC RATS' PENILE TISSUES AND POTENTIAL ROLE OF MIR-92A IN ERECTILE DYSFUNCTION Jun Yang, Tao Wang, Hua Xu, Shaogang Wang, Jihong Liu, and Zhangqun Ye Jun YangJun Yang Wuhan, China, People's Republic of More articles by this author , Tao WangTao Wang Wuhan, China, People's Republic of More articles by this author , Hua XuHua Xu Wuhan, China, People's Republic of More articles by this author , Shaogang WangShaogang Wang Wuhan, China, People's Republic of More articles by this author , Jihong LiuJihong Liu Wuhan, China, People's Republic of More articles by this author , and Zhangqun YeZhangqun Ye Wuhan, China, People's Republic of More articles by this author View All Author Informationhttps://doi.org/10.1016/j.juro.2013.02.614AboutPDF ToolsAdd to favoritesDownload CitationsTrack CitationsPermissionsReprints ShareFacebookTwitterLinked InEmail INTRODUCTION AND OBJECTIVES MicroRNAs are a recently discovered class of endogenous, small, noncoding RNAs, which play regulatory roles in several biological processes. However, the role of miRNAs in erectile dysfunction (ED) is currently completely unknown. This study was designed to identify specific miRNA whose expression is altered in diabetes-related ED and explore the role of miR-92a in diabetes-induced ED. METHODS A streptozotocin-induced diabetes rat model was established and the erectile function was evaluated by electrical stimulation of cavernous nerve twelve weeks after diabetes induction. Global miRNAs expression in penile tissues from normal rats and diabetic ED rats were measured using Agilent micoRNA microarray and the aberrantly expressed miRNAs were further confirmed by quantitative real-time polymerase chain reaction (PCR). The mRNA and protein expression level of endothelial nitric oxide synthase (eNOS) were detected by quantitative real-time PCR and western blot. MiR-92a functional assays were performed on rat aortic endothelial cells. RESULTS Compared to normal control rats, the erectile function (the ratio of maximal intracavernous pressure to mean arterial blood pressure) was found to be dramatically decreased in diabetic rats. Twenty-eight miRNAs were identified significantly dysregulated in diabetic rat's penile tissues. Among these altered miRNAs, miR-92a expression was dramatically up-regulated in diabetes-induced ED. The expression level of eNOS was significantly lower in diabetic rats' penes than that in normal control rats. Overexpression of miR-92a significantly decreased the expression of eNOS mRNA and protein in rat aortic endothelial cells. On the contrary, inhibition of miR-92a significantly increased the expression of eNOS mRNA and protein in rat aortic endothelial cells. CONCLUSIONS This is the first report demonstrating the altered microRNA expression signature in diabetes-associated ED. In vitro study showed that miR-92a was an important regulator of eNOS expression in endothelial cells, indicating upregulation of miR-92a might play an important role in diabetes-associated deterioration of erectile function. © 2013 by American Urological Association Education and Research, Inc.FiguresReferencesRelatedDetails Volume 189Issue 4SApril 2013Page: e421-e422 Advertisement Copyright & Permissions© 2013 by American Urological Association Education and Research, Inc.MetricsAuthor Information Jun Yang Wuhan, China, People's Republic of More articles by this author Tao Wang Wuhan, China, People's Republic of More articles by this author Hua Xu Wuhan, China, People's Republic of More articles by this author Shaogang Wang Wuhan, China, People's Republic of More articles by this author Jihong Liu Wuhan, China, People's Republic of More articles by this author Zhangqun Ye Wuhan, China, People's Republic of More articles by this author Expand All Advertisement Advertisement PDF downloadLoading ...

1030 THE EFFECT AND TOLERABILITY OF ALLOGENIC ADIPOSE-DERIVED STEM CELL ON ERECTILE DYSFUNCTION INDUCED BY CAVERNOUS NERVE INJURY

titative real-time polymerase chain reaction (PCR). The mRNA and protein expression level of endothelial nitric oxide synthase (eNOS) were detected by quantitative real-time PCR and western blot. MiR-92a functional assays were performed on rat aortic endothelial cells. RESULTS: Compared to normal control rats, the erectile function (the ratio of maximal intracavernous pressure to mean arterial blood pressure) was found to be dramatically decreased in diabetic rats. Twenty-eight miRNAs were identified significantly dysregulated in diabetic rat’s penile tissues. Among these altered miRNAs, miR-92a expression was dramatically up-regulated in diabetes-induced ED. The expression level of eNOS was significantly lower in diabetic rats’ penes than that in normal control rats. Overexpression of miR-92a significantly decreased the expression of eNOS mRNA and protein in rat aortic endothelial cells. On the contrary, inhibition of miR-92a significantly increased the expression of eNOS mRNA and protein in rat aortic endothelial cells. CONCLUSIONS: This is the first report demonstrating the altered microRNA expression signature in diabetes-associated ED. In vitro study showed that miR-92a was an important regulator of eNOS expression in endothelial cells, indicating upregulation of miR-92a might play an important role in diabetes-associated deterioration of erectile function.

S‐allyl cysteine restores erectile function through inhibition of reactive oxygen species generation in diabetic rats

Excessive production of reactive oxygen species (ROS) by an overactive nicotinamide adenine dinucleotide phosphate (NADPH) oxidase system in penile tissue is an important mechanism of erectile dysfunction (ED). S-allyl cysteine (SAC), a bioactive component derived from garlic, was recently reported to exert versatile antioxidant properties. We hypothesized that SAC would be able to resolve diabetes-related ED by reducing ROS generation, and designed this study to investigate this possibility as well as to determine the related underlying mechanisms. A streptozotocin-induced diabetes rat model was established and used for comparative analysis of 4-week treatment regimens with insulin or SAC. The ratio of maximal intracavernous pressure (ICP) to mean arterial blood pressure (MAP) was measured to determine erectile function. Differential levels of ROS, NADPH oxidase subunits, nitric oxide (NO)/cyclic guanosine monophosphate (cGMP) signalling pathway, and apoptosis were evaluated in cavernous tissues. Max ICP/MAP was found to be markedly decreased in untreated diabetic rats; SAC, but not insulin, treatment restored the ratio to baseline (in non-diabetic untreated controls). The corpus cavernosum of untreated diabetic rats showed increased p47(phox) and p67(phox) expression, ROS production and penile apoptotic index, and decreased phospho-endothelial nitric oxide synthase (phospho-eNOS, Ser1177) expression, cGMP concentration, B-cell lymphoma 2 (Bcl-2)/Bcl-2-associated X protein (Bax) ratio and smooth muscle cell number. SAC treatment normalized all the diabetes-induced effects, whereas insulin treatment partially normalized the alterations, but produced no effects on P47(phox) expression, penile ROS level, apoptotic index, Bcl-2/Bax ratio and smooth muscle cell number. Collectively, these data indicate that SAC treatment can restore erectile function in diabetic rats by preventing ROS formation through modulation of NADPH oxidase subunit expression. Furthermore, the poor efficacy of conventional insulin treatment for diabetic ED may be associated with an elevated level of ROS in penile tissue.

Schwann cell‐mediated delivery of glial cell line‐derived neurotrophic factor restores erectile function after cavernous nerve injury

To evaluate the time-course of functional recovery after cavernous nerve injury using glial cell line-derived neurotrophic factor-transduced Schwann cell-seeded silicon tubes. Sections of the cavernous nerves were excised bilaterally (5 mm), followed by immediate bilateral surgical repair. A total of 20 study nerves per group were reconstructed by interposition of empty silicon tubes and silicon tubes seeded with either glial cell line-derived neurotrophic factor-overexpressing or green fluorescent protein-expressing Schwann cells. Control groups were either sham-operated or received bilateral nerve transection without nerve reconstruction. Erectile function was evaluated by relaparotomy, electrical nerve stimulation and intracavernous pressure recording after 2, 4, 6, 8 and 10 weeks. The animals underwent re-exploration only once, and were killed afterwards. The nerve grafts were investigated for the maturation state of regenerating nerve fibers and the fascular composition. Recovery of erectile function took at least 4 weeks in the current model. Glial cell line-derived neurotrophic factor-transduced Schwann cell grafts restored erectile function better than green fluorescent protein-transduced controls and unseeded conduits. Glial cell line-derived neurotrophic factor-transduced grafts promoted an intact erectile response (4/4) at 4, 6, 8 and 10 weeks that was overall significantly superior to negative controls (P < 0.001). Maximum intracavernous pressure on electrostimulation was significantly elevated using glial cell line-derived neurotrophic factor-transduced grafts compared with negative controls (P = 0.018) and unseeded tubes (P = 0.034). Return of function was associated with the electron microscopic evidence of preganglionic myelinated nerve fibers and postganglionic unmyelinated axons. Schwann cell-mediated delivery of glial cell line-derived neurotrophic factor presents a viable approach for the treatment of erectile dysfunction after cavernous nerve injury.

Protective Effects of Hydrogen-Rich Saline Against Erectile Dysfunction in a Streptozotocin Induced Diabetic Rat Model

Hydrogen has antioxidative stress and anti-inflammatory effects. We investigated the effect of hydrogen on erectile dysfunction in streptozotocin induced diabetic rats. Diabetes was induced in Sprague-Dawley® rats by a single intravenous injection of streptozotocin. Diabetic rats were then randomized to a diabetes mellitus group and to a diabetic group that received hydrogen saline. The latter 8 rats were fed saturated hydrogen saline (5 ml/kg per day) by intragastric administration for 8 weeks. At the end of week 8 erectile function was assessed by measuring the increase in intracavernous pressure after cavernous nerve electrostimulation. We measured nitric oxide synthase activity, and malondialdehyde, 8-hydroxydeoxyguanosine, and nitrite and nitrate in the corpus cavernosum. eNOS protein immunolocalization in cavernous tissues was detected by immunohistochemistry. eNOS, Bcl-2 and Bax protein expression was determined by Western blot. We determined eNOS, Bcl-2 and Bax mRNA using real-time reverse transcriptase-polymerase chain reaction. Oxidative stress is involved in the pathophysiological mechanism of erectile dysfunction. Maximum intracavernous pressure in diabetic rats decreased significantly compared to controls and increased significantly compared to untreated diabetic rats after hydrogen-rich saline treatment. Decreased nitric oxide synthase activity, nitrite and nitrate, and eNOS expression as well as increased 8-hydroxydeoxyguanosine and malondialdehyde were found in the diabetic group compared to controls. Hydrogen-rich saline improved nitric oxide synthase activity, and malondialdehyde, nitrite and nitrate, and 8-hydroxydeoxyguanosine levels in the diabetic rat corpus cavernosum. Decreased eNOS in diabetic rats was ameliorated by hydrogen-rich saline. Also, apoptosis in the diabetic rat corpus cavernosum was significantly enhanced compared with controls. Hydrogen-rich saline therapy may decrease apoptosis in cavernous tissues and it ameliorated erectile dysfunction in diabetic rats by inhibiting oxidative stress and apoptosis. Hydrogen-rich saline effectively improved erectile function in a streptozotocin induced diabetic rat model of erectile dysfunction.

Effects of Intracavernous Injection of Adipose-Derived Stem Cells on Cavernous Nerve Regeneration in a Rat Model

The aim of this study was to investigate effects of intracavernous injection of adipose-derived stem cells (ADSCs) on cavernous nerve (CN) regeneration and functional status in a nerve-crush rat model. Thirty Sprague-Dawley male rats were randomly divided into three equal groups: one group underwent sham operation, while two groups underwent bilateral CN crush. Crush-injury group was treated at the time of injury with intracavernous injection of ADSCs, or injured control group with no further intervention. Erectile function was assessed by CN electrostimulation after 3 months. Penile tissue and crushed nerves were collected for histology. Three months after surgery, in the group that underwent bilateral nerve crushing with no further intervention, the functional evaluation showed a lower mean maximal intracavernous pressure (ICP) and maximal ICP per mean arterial pressure (MAP) with CN stimulation than those in the sham group. In the group with an immediate intracavernous injection of ADSCs, the mean maximal ICP and maximal ICP/MAP were significantly higher than those in the injured control group. Histologically, the group with the intracavernous injection of ADSCs had more myelinated axons of CNs and more NADPH-diaphorase-positive nerve fibers than the injured control group but fewer than the sham group. Intracavernous injection of ADSCs treatment had beneficial effects on the smooth muscle/collagen ratio in the corpus cavernosum. These results show that the intracavernous injection of ADSCs to the site of CN-crush injury facilitates nerve regeneration and recovery of erectile function. Our research indicates that penile injection of ADSCs can improve recovery of erectile function in a rat model of neurogenic ED.

Transforming Growth Factor-β Type I Receptor Inhibitor Induces Functional and Morphologic Recovery in a Rat Model of Erectile Dysfunction and Cavernous Fibrosis

Purpose: To examine the effectiveness of small-molecule inhibitor of transforming growth factor-β (TGF-β) type I receptor, an activin receptor-like kinase 5 (ALK5), on erectile dysfunction (ED) in a rat model of cavernous fibrosis, in which fibrosis was induced by intracavernous injection of adenovirus expressing TGF-β1 (Ad-TGF-β1). Materials and Methods: Four-month-old Sprague-Dawley rats were divided into four groups (n=10 per group): age-matched controls without treatment, age-matched controls receiving intracavernous injection of LacZ adenovirus, and cavernous fibrosis rats receiving an intracavernous injection of saline or ALK5 inhibitor (5 mg/kg). ALK5 inhibitor or saline was administered on day 5 after injection of Ad-TGF-β1. On day 30, erectile function was assessed by electrical stimulation of the cavernous nerve and the penis was then harvested for histologic studies (n=6 per group) and for the measurement of the hydroxyproline level (n=4 per group). Results: Ad-TGF-β1-induced cavernous fibrosis rats treated with saline showed a significant decrease in cavernous smooth muscle and endothelial content, and an increase in collagen deposition, which resulted in profound deterioration of all erectile function parameters, such as the ratios of maximal intracavernous pressure (ICP), total ICP, and slope to mean arterial pressure. ALK5 inhibitor significantly restored erectile function in a rat model of cavernous fibrosis by increasing cavernous smooth muscle and endothelial content, and by blocking cavernous fibrosis. Conclusions: The results suggest that inhibition of the TGF-β pathway is a promising therapeutic strategy for the treatment of ED related to cavernous fibrosis from various cause

A Chinese Herbal Formula, Shuganyiyang Capsule, Improves Erectile Function in Male Rats by Modulating Nos-CGMP Mediators

To evaluate the effects of the Chinese herbal formula Shuganyiyang (SGYY) capsule on arteriogenic erectile dysfunction (ED) in a rat model and to investigate the underlying molecular mechanism. Forty male Sprague-Dawley rats were subjected to bilateral ligation of the internal iliac artery and then divided into 4 groups (n=10 per group). They were treated daily with either sildenafil (10.5 mg/kg), or SGYY at 1 of 2 dosages (1 g/kg and 0.5 g/kg) for 30 days. Erectile function was evaluated using cavernous nerve electrical stimulation after treatment, and the cavernous tissue specimens of all animals were harvested for gene and protein examination using real-time reverse transcriptase polymerase chain reaction, Western blot analysis, and cyclic guanosine monophosphate (cGMP) measurement. The ratio of the maximal intracavernous pressure to the mean arterial pressure was significantly higher in the SGYY (1 g/kg and 0.5 g/kg) rats than that in the models (P<.01). The gene and protein expression of 3 subtypes of nitric oxide synthase (NOS)--neuropathic (nNOS), inducible (iNOS), and endothelial (eNOS)--and cGMP concentrations in cavernous tissue in SGYY-treated rats were significantly higher than in the models. However, phosphodiesterase type 5 (PDE5) expression in the SGYY rats was lower than those in models (P<.01 or P<.05). SGYY significantly improves the maximal intracavernous pressure in arteriogenic ED in a rat model. The underlying mechanism of action of SGYY involves increasing the expression of some main factors in the NOS-cGMP pathway and reducing the expression of PDE5.

914 TIME-DEPENDENT STRUCTURAL AND FUNCTIONAL CHANGES IN CORPUS CAVERNOSUM FOLLOWING CAVERNOUS NERVE INJURY IN RATS

You have accessJournal of UrologySexual Function/Dysfunction/Andrology: Basic Research1 Apr 2011914 TIME-DEPENDENT STRUCTURAL AND FUNCTIONAL CHANGES IN CORPUS CAVERNOSUM FOLLOWING CAVERNOUS NERVE INJURY IN RATS Sung Yong Cho, Soo Woong Kim, and Jae-Seung Paick Sung Yong ChoSung Yong Cho Seoul, Korea, Republic of More articles by this author , Soo Woong KimSoo Woong Kim Seoul, Korea, Republic of More articles by this author , and Jae-Seung PaickJae-Seung Paick Seoul, Korea, Republic of More articles by this author View All Author Informationhttps://doi.org/10.1016/j.juro.2011.02.805AboutPDF ToolsAdd to favoritesDownload CitationsTrack CitationsPermissionsReprints ShareFacebookTwitterLinked InEmail INTRODUCTION AND OBJECTIVES Erectile dysfunction (ED) is still a frequent complication following radical prostatectomy (RP) despite the advent of surgical techniques. Post-RP ED mainly results from injury to cavernous nerve (CN). It is postulated that damage to the erectile tissue secondary to neuropraxia also plays an important role. This study was designed to investigate time-dependent structural and functional changes in corpus cavernosum following CN injury in rat model. METHODS Ninety male Sprague-Dawley rats (10 weeks old) were divided into 4 groups: normal control (C), sham (S), bilateral CN resection (R), and bilateral CN crush injury (I) group. At 1, 4, 12 weeks after procedure, electric pelvic ganglion stimulation was done to assess erectile function by maximal intracavernous pressure (ICP)/mean arterial pressure (MAP) ratio. Penile tissue was assessed for apoptosis with immunohistochemistry. Expression of phospho-myosin phosphatase target subunit 1 (MYPT1), protein kinase B (Akt), and phospho-endothelial nitric oxide synthase (eNOS) were evaluated by Western blot. RESULTS There was no difference in ICP/MAP between C and S groups in each time period (mean ICP/MAP: 0.78–0.85). Bilateral CN resection caused persistent impairment of erectile function throughout the experimental period (mean ICP/MAP: 0.15–0.24). Bilateral CN crush injury also resulted in deterioration of erectile function, however, mean ICP/MAP gradually increased over the time course (1-week: 0.23, 4-week: 0.33, 12-week: 0.39). The mean apoptotic index in R group was significantly higher than that in C or S group at all time points. The apoptotic index in I group was significantly high after 1-week of injury, however, the apoptotic index gradually decreased over the time. MYPT1 phosphorylation significantly increased after 1-week of injury and gradually increased according the duration of injury both in R and I groups. Both R and I group showed transient decrease in expressions of phospho-Akt and phospho-eNOS at 1-week of injury. CONCLUSIONS These results suggest that CN injury itself plays a more important role than structural and functional alterations in corpus cavernosum secondary to neuropraxia in the pathogenesis of post-RP ED. However, further investigations are needed to elucidate the role of up-regulation of RhoA/Rho-kinase pathway in post-RP ED. © 2011 by American Urological Association Education and Research, Inc.FiguresReferencesRelatedDetails Volume 185Issue 4SApril 2011Page: e366 Advertisement Copyright & Permissions© 2011 by American Urological Association Education and Research, Inc.MetricsAuthor Information Sung Yong Cho Seoul, Korea, Republic of More articles by this author Soo Woong Kim Seoul, Korea, Republic of More articles by this author Jae-Seung Paick Seoul, Korea, Republic of More articles by this author Expand All Advertisement Advertisement PDF DownloadLoading ...