Major Pelvic Ganglion Research Articles

980 - Major pelvic ganglion neurons express CXCR4, which binds stromal derived factor-1 and enhances neurotrophin protein levels and neurogenesis

980 - Major pelvic ganglion neurons express CXCR4, which binds stromal derived factor-1 and enhances neurotrophin protein levels and neurogenesis

017 Differential Effects on MPG Neurons and Penile Vasculature after Conformal Prostate Radiation in Rats

Prostatic radiation therapy (RT) is presumed to cause erectile dysfunction (ED) through damage to the vasculature and the nerves supplying the penis. This study examined the impact of prostatic RT on 1) vascular function in the internal pudendal artery (IPA) and penis and 2) the effect of in vivo prostate RT on the ex vivo survival and growth of major pelvic ganglia (MPG) neurons. Adult male Sprague-Dawley rats underwent conformal single fraction 25Gy RT using kilovoltage small animal microirradiator to the prostate or sham treatment. Erectile function was assessed by electrical stimulation of the cavernous nerve and ICP/MAP measurement at 2 or 10 weeks post-RT (n=10/grp). MPG were then excised; neurons were dissociated and cultured. Axon length and branching, and neuronal nitric oxide synthase (nNOS), tyrosine hydroxylase (TH) and TUNEL assay expression were measured in neuronal cultures at 72h. IPA and penises were excised and mounted in myograph tissue bath. Concentration response curves to phenylephrine (PE), acetylcholine (ACh), DEA NONOate, or sodium nitroprusside (SNP), and electrical field stimulated (EFS) contraction and NANC relaxation were assessed.

161 Low Intensity Extracorporeal Shock Wave Therapy Activates Endogenous Progenitor/Stem Cells as Indicated by Histone 3 Phosphorylation

Low Intensity Extracorporeal Shock Wave Therapy (Li-ESWT) has been employed for many years to treat ED yet its mechanism of action remains poorly defined. We have previously demonstrated that the therapeutic effects from Li-ESWT may be partially related to the activation of endogenous progenitor/stem cells and we are endeavoring to further describe these pathways. To determine the mechanism by which Li-ESWT activates endogenous stem cells by interrogating histone 3 phosphorylation, which occurs only during the mitotic phase of the cell cycle. Male Sprague-Dawley (SD) rats were treated with 5-ethynyl-2'-deoxyuridine (EdU) pulse followed by Li-ESWT, and cohort analysis was performed. Additionally, rat adipose derived stem cells (RADSCs) and rat penile cavernous smooth muscle cells (RCSMCs) were also treated with Li-ESWT. Fifty male SD rats at 12 weeks old were grouped into three cohorts: 1). Sham; 2). Sub-acute: the animals underwent bilateral cavernous nerve injury (BCNI) then were separated into control and Li-ESWT groups. One week after BCNI, the Li-ESWT group were injected with EdU (50mg/kg, i.p) 30 minutes before Li-ESWT (0.02mJ/mm2, 3 Hz, 300 pulses). One week later, ICP/MAP were measured. 3). Chronic: the animals underwent BCNI then grouped into control and Li-ESWT groups. One week after BCNI, the animals were treated with Li-ESWT (0.02mJ/mm2, 3 Hz, 300 pulses) twice a week for 4 weeks. EdU was injected 30 min before the first and last Li-ESWT. One week after the last Li-ESWT, ICP/MAP were measured. The penile erectile tissues and major pelvic ganglion (MPG) were harvested for histological study to assess smooth muscle/collagen content and endothelium content in the corpora cavernosa. EdU as marker of cell activation and phosphorylated histone 3 (H3P) as marker of the mitotic phase of the cell cycle were also assessed. To confirm the effect of Li-ESWT on the phosphorylation of H3 in vitro, RADSCs and RCSMCs were treated with Li-ESWT (0.02mJ/mm2, 3 Hz, 100 pulses), and EdU incorporation rate and the expression of H3P was assessed.

018 TNF-alpha Inhibition Improves Parasympathetic Nerve Function and is Associated with Altered Macrophage Infiltration of the Major Pelvic Ganglion following Nerve Injury

018 TNF-alpha Inhibition Improves Parasympathetic Nerve Function and is Associated with Altered Macrophage Infiltration of the Major Pelvic Ganglion following Nerve Injury

164 The Effects of Multiple Adipose-Derived Stem Cell Intracorporeal Injections on Erectile Dysfunction in a Rat Model of Cavernosal Nerve Injury

Nerve injury after radical prostatectomy leads to erectile dysfunction in over half of treated patients. Despite contemporary advancements, current therapies are inefficient. Recently, experiments utilizing stem cell therapy have shown promising outcomes. In this study, using a rat model of cavernosal nerve injury (CNI), we sought to discover the effect of intracorporal injection (IC) of adipose-derived stem cells (ADSC) on erectile function (EF). Sprague-Dawly rats were randomized into four groups of rats (n=8/group): 1) EXP-1 group in which the animals underwent laparotomy (Lap) with CNI and IC injection of ADSC at the time of surgery. 2) EXP-2 group in which the rats underwent Lap with CNI and IC injection of ADSC both at the time of surgery and three weeks post CNI. 3) Crush group underwent Lap with CNI, and 4) The Sham control group underwent Lap and immediate closure. Six weeks after CNI, all four groups received EF evaluation via cavernosal nerve stimulation at 2.5V, 5V, and 7.5V and measurement of the intracorporal pressure response. Penile and major pelvic ganglion tissue was harvested for immunohistochemical (IHC) analysis.

Intravenous Infusion of Bone Marrow-Derived Mesenchymal Stem Cells Reduces Erectile Dysfunction Following Cavernous Nerve Injury in Rats.

IntroductionIntravenous preload (delivered before cavernous nerve [CN] injury) of bone marrow–derived mesenchymal stem cells (MSCs) can prevent or decrease postoperative erectile dysfunction (J Sex Med 2015;12:1713–1721). In the present study, the potential therapeutic effects of intravenously administered MSCs on postoperative erectile dysfunction were evaluated in a rat model of CN injury.MethodsMale Sprague-Dawley rats were randomized into 2 groups after electric CN injury. Intravenous infusion of bone marrow–derived MSCs (1.0 × 106 cells in Dulbecco's modified Eagle's medium 1 mL) or vehicle (Dulbecco's modified Eagle's medium 1 mL) was performed 3 hours after electrocautery-induced CN injury.Main Outcome MeasuresTo assess erectile function, we measured intracavernous pressure at 4 weeks after MSC or vehicle infusion. Histologic examinations were performed to investigate neuronal innervation and inhibition of smooth muscle atrophy. Green fluorescent protein–positive bone marrow–derived MSCs were used for cell tracking. To investigate mRNA expression levels of neurotrophins in the major pelvic ganglia (MPGs), quantitative real-time polymerase chain reaction was performed.ResultsThe decrease of intracavernous pressure corrected for arterial pressure and area under the curve of intracavernous pressure in the bone marrow–derived MSC group was significantly lower than that in the vehicle group at 4 weeks after infusion (P < .05). Retrograde neuronal tracing indicated that the MSC group had a larger number of FluoroGold-positive neurons in the MPGs compared with the vehicle group. The ratio of smooth muscle to collagen in the MSC group was significantly higher than in the vehicle group. Green fluorescent protein–positive bone marrow–derived MSCs were detected in the MPGs and injured CNs using confocal microscopy, indicating homing of cells to the MPGs and injured CNs. Brain-derived neurotrophic factor and glial cell-derived neurotrophic factor expression levels in the MPGs were significantly higher in the MSC group than in the vehicle group (P < .01).ConclusionIntravenous infusion of bone marrow–derived MSCs after CN injury might have therapeutic efficacy in experimental erectile dysfunction.Matsuda Y, Sasaki M, Kataoka-Sasaki Y, et al. Intravenous Infusion of Bone Marrow–Derived Mesenchymal Stem Cells Reduces Erectile Dysfunction Following Cavernous Nerve Injury in Rats. Sex Med 2018;6:49–57.

Dickkopf2 rescues erectile function by enhancing penile neurovascular regeneration in a mouse model of cavernous nerve injury

Penile erection is a neurovascular event and neurologic or vascular disturbances are major causes of erectile dysfunction (ED). Radical prostatectomy for prostate cancer not only induces cavernous nerve injury (CNI) but also results in cavernous angiopathy, which is responsible for poor responsiveness to oral phosphodiesterase-5 inhibitors. Dickkopf2 (DKK2) is known as a Wnt signaling antagonist and is reported to promote mature and stable blood vessel formation. Here, we demonstrated in CNI mice that overexpression of DKK2 by administering DKK2 protein or by using DKK2-Tg mice successfully restored erectile function: this recovery was accompanied by enhanced neural regeneration through the secretion of neurotrophic factors, and restoration of cavernous endothelial cell and pericyte content. DKK2 protein also promoted neurite outgrowth in an ex vivo major pelvic ganglion culture experiment and enhanced tube formation in primary cultured mouse cavernous endothelial cells and pericytes co-culture system in vitro. In light of critical role of neuropathy and angiopathy in the pathogenesis of radical prostatectomy-induced ED, reprogramming of damaged erectile tissue toward neurovascular repair by use of a DKK2 therapeutic protein may represent viable treatment option for this condition.

The effect of cavernous nerve traction on erectile function in rats.

We performed this study to evaluate the effect of cavernous nerve (CN) traction on erectile function in rats. Thirty-two 8- week-old Sprague–Dawley rats were divided into four groups: control, 1-minute CN traction, 2-minute CN traction, and 2-minute CN crush. CN traction was performed using a glass hook with a tensile force of 0.2 Newton. One month later, the mean arterial pressure (MAP) and intracavernosal pressure (ICP) in response to CN stimulation were measured to assess erectile function. The penis and major pelvic ganglion (MPG) were harvested to explore the expression of neuronal nitric oxide synthase (nNOS) and neurofilament, fibrosis and apoptosis. The ICP/MAP ratio was reduced in the 2-minute CN traction group compared with the control group (P < 0.05). The ICP/MAP ratio in the CN crush group was lower than in the other three groups (P < 0.05, for each). Expression of nNOS in both MPG and dorsal penile nerve was lower in the CN traction group than in the control group, but was higher than in the CN crush group (P < 0.05). Nerve fiber number in the dorsal penile nerve was reduced by 2-minute CN traction (P < 0.05). The ratios of collagen to smooth muscle content and the apoptosis were both increased the in 2-minute CN traction group compared with the control group (P < 0.05). The findings indicate that CN traction is an effective CN injury model and the injury it caused is relatively mild compared with the CN crush model.

Effects of FK1706 on nerve regeneration and bladder recovery after spinal cord injury

Objective To investigate the effects of FK1706 on nerve regeneration and bladder function recovery after spinal cord injury in rats. Methods Thirty adult male SD rats weighing 230-250 g were randomly divided into three groups for different treatments: FK1706 group, neurorrhaphy group and control group (10 rats each group). In FK1706 group, the spinal cords were transected in the level of L5 to make rat spinal injury model. Then the distal stump of L6VR was sutured to the lateral face of L4 ventral root (L4VR) in an end-to-side (ETS) fashion under microscope. FK1706 (0.3 mg/kg) was administrated subcutaneously for 5 consecutive days per week for a total of 8 weeks after neurorrhaphy. In neurorrhaphy group, the same operation as FK1706 group was performed but without FK1706 applied after surgery. In control group, left ventral and dorsal roots of L5, L6, S1 and S2 were transected but the left L6VR was preserved as normal control. After four months, FG and FB were injected into left major pelvic ganglion (MPG) and sciatic nerve (SN), respectively, for retrograde nerve tracing to ascertain whether neural pathway was established after surgery. The left L6VR distal to coaptation was harvested for semi-thin sectioning and toluidine blue staining to count the number of myelinated axons. Urodynamic parameters such as maximum detrusor pressure (MDP) and residual urine volume (RUV) were measured in rats through BL-420 biological experimental system. Results The neural pathways were successfully established between left L4VR and L6VR in FK1706 group and neurorrhaphy group through retrograde nerve tracing. The number of regenerated myelinated axons of left L6VR distal to coaptation in FK1706 group and neurorrhaphy group was 535.7±45.2 and 337.4±56.5, respectively, which had a significant difference (P=0.000). The MDP and RUV were (44.6±6.7) mmHg (1 mmHg=0.133 kPa) and (1.16±0.24) ml in FK1706 group, respectively, when the left L4VR proximal to coaptation was stimulated by BL-420 experimental system. The MDP and RUV were (32.5±5.4) mmHg and (2.36±0.34) ml in neurorrhaphy group, respectively. There were statistically significant differences in the MDP and RUV between the two groups (P=0.000). Conclusion The effects of nerve regeneration and bladder function recovery could be evidently enhanced by FK1706 after neurorrhaphy in rat spinal cord injury model. Key words: FK1706; Spinal cord injury; Nerve regeneration; Functional recovery

CAMP-dependent post-translational modification of neuronal nitric oxide synthase neuroprotects penile erection in rats.

To evaluate neuronal nitric oxide (NO) synthase (nNOS) phosphorylation, nNOS uncoupling, and oxidative stress in the penis and major pelvic ganglia (MPG), before and after the administration of the cAMP-dependent protein kinase A (PKA) agonist colforsin in a rat model of bilateral cavernous nerve injury (BCNI),which mimics nerve injury after prostatectomy. Adult male Sprague-Dawley rats were divided into BCNI and sham-operated groups. Each group included two subgroups: vehicle and colforsin (0.1 mg/kg/day i.p.). After 3 days, erectile function (intracavernosal pressure) was measured and penis and MPG were collected for molecular analyses of phospho (P)-nNOS (Ser-1412 and Ser-847), total nNOS, nNOS uncoupling, binding of protein inhibitor of nNOS (PIN) to nNOS, gp91phox subunit of NADPH oxidase, active caspase 3, PKA catalytic subunit α (PKA-Cα; by Western blot) and oxidative stress (hydrogen peroxide [H2 O2 ] and superoxide by Western blot and microdialysis method). Erectile function was decreased 3 days after BCNI and normalized by colforsin. nNOS phosphorylation on both positive (Ser-1412) and negative (Ser-847) regulatory sites, and nNOS uncoupling, were increased after BCNI in the penis and MPG, and normalized by colforsin. H2 O2 and total reactive oxygen species production were increased in the penis after BCNI and normalized by colforsin. Protein expression of gp91phox was increased in the MPG after BCNI and was normalized by colforsin treatment. Binding of PIN to nNOS was increased in the penis after BCNI and was normalized by colforsin treatment. Protein expression of active Caspase 3 was increased in the MPG after BCNI and was normalized by colforsin treatment. Protein expression of PKA-Cα was decreased in the penis after BCNI and normalized by colforsin. Collectively, BCNI impairs nNOS function in the penis and MPG by mechanisms involving its phosphorylation and uncoupling in association with increased oxidative stress, resulting in erectile dysfunction. PKA activation by colforsin reverses these molecular changes and preserves penile erection in the face of BCNI.

Bilateral Cavernous Nerve Crush Injury in the Rat Model: A Comparative Review of Pharmacologic Interventions.

It is common for men to develop erectile dysfunction after radical prostatectomy. The anatomy of the rat allows the cavernous nerve (CN) to be identified, dissected, and injured in a controlled fashion. Therefore, bilateral CN injury (BCNI) in the rat model is routinely used to study post-prostatectomy erectile dysfunction. To compare and contrast the available literature on pharmacologic intervention after BCNI in the rat. A literature search was performed on PubMed for cavernous nerve and injury and erectile dysfunction and rat. Only articles with BCNI and pharmacologic intervention that could be grouped into categories of immune modulation, growth factor therapy, receptor kinase inhibition, phosphodiesterase type 5 inhibition, and anti-inflammatory and antifibrotic interventions were included. To assess outcomes of pharmaceutical intervention on erectile function recovery after BCNI in the rat model. The ratio of maximum intracavernous pressure to mean arterial pressure was the main outcome measure chosen for this analysis. All interventions improved erectile function recovery after BCNI based on the ratio of maximum intracavernous pressure to mean arterial pressure results. Additional end-point analysis examined the corpus cavernosa and/or the major pelvic ganglion and CN. There was extreme heterogeneity within the literature, making accurate comparisons between crush injury and therapeutic interventions difficult. BCNI in the rat is the accepted animal model used to study nerve-sparing post-prostatectomy erectile dysfunction. However, an important limitation is extreme variability. Efforts should be made to decrease this variability and increase the translational utility toward clinical trials in humans. Haney NM, Nguyen HMT, Honda M, etal. Bilateral Cavernous Nerve Crush Injury in the Rat Model: A Comparative Review of Pharmacologic Interventions. Sex Med Rev 2018;6:234-241.

Erectile Dysfunction in Wistar Audiogenic Rats Is Associated With Increased Cavernosal Contraction and Decreased Neuronal Nitric Oxide Synthase Protein Expression

To test the hypothesis that naive Wistar audiogenic rats (WARs) display erectile dysfunction (ED), which is associated with increased sympathetic-mediated contractile tone and decreased nitric oxide-mediated relaxation responses of the cavernous tissue. Changes in the ratio of the maximal intracavernosal pressure-mean arterial pressure after the electrical stimulation of the right major pelvic ganglion were determined in vivo. Cavernosal contractility was induced by electrical field stimulation and phenylephrine. In addition, nonadrenergic-noncholinergic (NANC)-induced relaxation was determined. Rho-kinase (ROCK) pathway proteins, neuronal nitric oxide synthase (nNOS) protein expression, and endothelial nitric oxide synthase (eNOS) and extracellular signal-regulated kinase 1/2 activities were determined by Western blot. WARs display a significant decrease in maximal intracavernosal pressure-mean arterial pressure responses suggesting ED in this strain. Sympathetic-mediated contractile responses were increased in WARs and contractile responses to phenylephrine were not changed. The increased sympathetic-mediated contractile responses were not associated with changes in the ROCK pathway. On the other hand, NANC-mediated relaxation responses were significantly reduced in WARs. This functional response was accompanied by decreased nNOS and total eNOS protein expressions, augmented phosphorylated eNOS, and decreased extracellular signal-regulated kinase 1/2 phosphorylation levels. Our data have demonstrated that naive WARs display ED in vivo that is associated with increased sympathetic-mediated contractile responses and decreased NANC-mediated relaxation responses. The increase in contractile responses is independent of the ROCK pathway, and the changes in relaxation responses are associated with a decrease in nNOS protein expression, which may activate compensatory mechanisms in the cavernous tissue.

MP41-15 STEM CELL ACTIVATION IN THE MAJOR PELVIC GANGLION IS ENHANCED BY STROMAL DERIVED FACTOR-1 PENILE INJECTIONS FOLLOWING NERVE INJURY

You have accessJournal of UrologyStem Cell Research1 Apr 2017MP41-15 STEM CELL ACTIVATION IN THE MAJOR PELVIC GANGLION IS ENHANCED BY STROMAL DERIVED FACTOR-1 PENILE INJECTIONS FOLLOWING NERVE INJURY Nikolai Sopko, Hotaka Matsui, Takahiro Yoshida, Xiaopu Liu, Max Kates, and Trinity Bivalacqua Nikolai SopkoNikolai Sopko More articles by this author , Hotaka MatsuiHotaka Matsui More articles by this author , Takahiro YoshidaTakahiro Yoshida More articles by this author , Xiaopu LiuXiaopu Liu More articles by this author , Max KatesMax Kates More articles by this author , and Trinity BivalacquaTrinity Bivalacqua More articles by this author View All Author Informationhttps://doi.org/10.1016/j.juro.2017.02.1283AboutPDF ToolsAdd to favoritesDownload CitationsTrack CitationsPermissionsReprints ShareFacebookTwitterLinked InEmail INTRODUCTION AND OBJECTIVES Stem cells are believed to play a role in nerve regeneration following nerve injury. Stromal Derived Factor-1 (SDF1) is potent stem cell chemokine. We investigated whether penile injections with SDF1 following bilateral nerve crush injury (BCNI) can enhance stem cell recruitment and activation in the major pelvic ganglion (MPG). METHODS Sprague Dawley (350g) male rats underwent sham procedure or BCNI (n=10/group). Starting on the day of surgery, BCNI animals received penile injections with 1ug of SDF1 or saline QOD for 5 injections. Sham animals received saline penile injections only. 2 weeks after BCNI, intracorporeal pressure (ICP) response to cavernous nerve stimulation was assessed (n=5/group) and MPGs were collected and RNA was isolated (n=5/group). Stem cell activity in the MPG was assessed using a stem cell expression array expressed as mean fold-change ± SE normalized to sham. RESULTS SDF1 penile injections resulted in improved ICP preservation following BCNI compared to animals receiving saline injections. Sham animals had significantly greater (P<0.05, 1-way ANOVA with Tukey’s post-hoc testing) than BCNI+saline at all voltages (2, 4, 6, 8v), whereas there was no significant difference between Sham and BCNI+SDF1 at any voltages. Additionally, BCNI+SDF1 had greater ICP at 2v and 4v compared to BCNI+saline (0.40±0.09 vs. 0.11±0.08, p<0.05 and 0.47±0.11 vs. 0.12±0.08, p<0.05, respectively). Stem cell-associated gene expression normalized to Shams was globally increased following BCNI and BCNI+SDF1 had a greater increase in expression compared to BCNI+saline (7.89±0.67 fold vs. 1.87±0.15 fold, p<0.0001). On subset analysis, stem cell pathways had significantly greater expression in BCNI+SDF1 compared to BCNI+saline including cytokines and growth factors (6.45±0.63 vs. 1.86±0.13, p<0.0001), Notch pathway (7.72±0.96 vs. 1.95±0.17, p<0.0001), Wnt pathway (7.01±0.68 vs. 1.87±0.12, p<0.0001), mesenchymal stem cell markers (6.33±1.16 vs. 1.82±0.40, p=0.0015), and neural cell lineage markers (6.63±0.51 vs. 1.85±0.14, p=0.0003). CONCLUSIONS SDF1 penile injections improve preservation of erectile function following BCNI and are associated with increased stem cell pathway activation in MPG. © 2017FiguresReferencesRelatedDetails Volume 197Issue 4SApril 2017Page: e541 Advertisement Copyright & Permissions© 2017MetricsAuthor Information Nikolai Sopko More articles by this author Hotaka Matsui More articles by this author Takahiro Yoshida More articles by this author Xiaopu Liu More articles by this author Max Kates More articles by this author Trinity Bivalacqua More articles by this author Expand All Advertisement Advertisement PDF downloadLoading ...

MP45-09 RADIATION INCREASED APOPTOSIS OF NITRERGIC NEURONS CULTURED FROM THE MAJOR PELVIC GANGLIA

You have accessJournal of UrologySexual Function/Dysfunction: Basic Research & Pathophysiology I1 Apr 2017MP45-09 RADIATION INCREASED APOPTOSIS OF NITRERGIC NEURONS CULTURED FROM THE MAJOR PELVIC GANGLIA Elena Pak, Bridget Koontz, and Johanna Hannan Elena PakElena Pak More articles by this author , Bridget KoontzBridget Koontz More articles by this author , and Johanna HannanJohanna Hannan More articles by this author View All Author Informationhttps://doi.org/10.1016/j.juro.2017.02.1427AboutPDF ToolsAdd to favoritesDownload CitationsTrack CitationsPermissionsReprints ShareFacebookTwitterLinked InEmail INTRODUCTION AND OBJECTIVES A third of men diagnosed with prostate cancer will undergo radiation therapy (RT) which frequently results in erectile dysfunction (ED). Prostatic radiation is presumed to cause damage to the vasculature and the nerves supplying the penis. There are no effective treatment strategies to prevent or recover radiation-induced ED which significantly impacts the quality of life of prostate cancer survivors. This study examined the impact of low and high radiation on neurite growth, branching and survival of sympathetic and nitrergic neurons cultured from the major pelvic ganglia (MPG). METHODS MPGs collected from male Sprague-Dawley rats (n=6) were dissociated and neurons plated on laminin coated glass cover slips. After 24 hours, neurons were irradiated at 2Gy or 8Gy, grown for an additional 48 hours and then compared to time-matched control neurons. Neurons were fixed and stained with immunofluorescence for neuron-specific class III beta-tubulin to measure axon length and branching, neuronal nitric oxide synthase (nNOS, nitrergic), tyrosine hydroxylase (TH; sympathetic) or TUNEL assay for apoptosis. Images were taken of all neurons on each cover slip at a magnification of 100x. RESULTS Neurite length was unchanged with radiation, however, neurite branching significantly decreased with both doses of radiation (CON: 3.0±0.11, 2Gy: 2.6±0.16, 8Gy: 2.5±0.16; p<0.005). There was a 3 to 4-fold increase in the percentage of apoptotic TUNEL positive neurons in both groups following radiation (p<0.0001). There was no change in the relative number of sympathetic TH positive neurons with radiation. In contrast, a marked decrease in nNOS positive neurons increased with the dose of radiation (CON: 45±4.4%, 2Gy: 20±3.1%, 8Gy: 5±0.7%; p<0.0001). CONCLUSIONS These data demonstrate that RT stimulates an increase in neuronal cell death and a substantial decrease in the number of erectile promoting nitrergic neurons. Although there is no change in neurite length, neurite branching which is essential for the establishment of appropriate neuronal connections and regeneration was impaired. Future studies will examine the impact of prostatic RT in an animal model to determine if these neuronal impairments contribute to ED in order to elucidate the pathological mechanisms to lead to new therapeutic radioprotection strategies for prostate cancer survivors. © 2017FiguresReferencesRelatedDetails Volume 197Issue 4SApril 2017Page: e614 Advertisement Copyright & Permissions© 2017MetricsAuthor Information Elena Pak More articles by this author Bridget Koontz More articles by this author Johanna Hannan More articles by this author Expand All Advertisement Advertisement PDF downloadLoading ...

Neurite outgrowth in cultured mouse pelvic ganglia - Effects of neurotrophins and bladder tissue.

Neurotrophic factors regulate survival and growth of neurons. The urinary bladder is innervated via both sympathetic and parasympathetic neurons located in the major pelvic ganglion. The aim of the present study was to characterize the effects of the neurotrophins nerve growth factor (NGF), brain derived neurotrophic factor (BDNF) and neurotrophin 3 (NT-3) on the sprouting rate of sympathetic and parasympathetic neurites from the female mouse ganglion. The pelvic ganglion was dissected out and attached to a petri dish and cultured in vitro. All three factors (BDNF, NT-3 and NGF) stimulated neurite outgrowth of both sympathetic and parasympathetic neurites although BDNF and NT-3 had a higher stimulatory effect on parasympathetic ganglion cells. The neurotrophin receptors TrkA, TrkB and TrkC were all expressed in neurons of the ganglia. Co-culture of ganglia with urinary bladder tissue, but not diaphragm tissue, increased the sprouting rate of neurites. Active forms of BDNF and NT-3 were detected in urinary bladder tissue using western blotting whereas tissue from the diaphragm expressed NGF. Neurite outgrowth from the pelvic ganglion was inhibited by a TrkB receptor antagonist. We therefore suggest that the urinary bladder releases trophic factors, including BDNF and NT-3, which regulate neurite outgrowth via activation of neuronal Trk-receptors. These findings could influence future strategies for developing pharmaceuticals to improve re-innervation due to bladder pathologies.

M1 Macrophages Are Predominantly Recruited to the Major Pelvic Ganglion of the Rat Following Cavernous Nerve Injury

IntroductionNeurogenic erectile dysfunction is a common sequela of radical prostatectomy. The etiology involves injury to the autonomic cavernous nerves, which arise from the major pelvic ganglion (MPG), and subsequent neuroinflammation, which leads to recruitment of macrophages to the injury site. Currently, two macrophage phenotypes are known: neurotoxic M1 macrophages and neuroprotective M2 macrophages. AimTo examine whether bilateral cavernous nerve injury (BCNI) in a rat model of erectile dysfunction would increase recruitment of neurotoxic M1 macrophages to the MPG. MethodsMale Sprague-Dawley rats underwent BCNI and the MPG was harvested at various time points after injury. The corpora cavernosa was used to evaluate tissue myographic responses to electrical field stimulation ex vivo. Quantitative real-time polymerase chain reaction was used to examine the gene expression of global macrophage markers, M1 macrophage markers, M2 macrophage markers, and cytokines and chemokines in the MPG. Mathematical calculation of the M1/M2 index was used to quantify macrophage changes temporally. Western blot of MPG tissues was used to evaluate the protein amount of M1 and M2 macrophage markers quantitatively. Immunohistochemistry staining of MPGs for CD68, CD86, and CD206 was used to characterize M1 and M2 macrophage infiltration. Main Outcome MeasuresCorpora cavernosa responsiveness ex vivo; gene (quantitative real-time polymerase chain reaction) and protein (western blot) expressions of M1 and M2 markers, cytokines, and chemokines; and immunohistochemical localization of M1 and M2 macrophages. ResultsBCNI impaired the corporal parasympathetic-mediated relaxation response to electrical field stimulation and enhanced the contraction response to electrical field stimulation. Gene expression of proinflammatory (Il1b, Il16, Tnfa, Tgfb, Ccl2, Ccr2) and anti-inflammatory (Il10) cytokines was upregulated in the MPG 48 hours after injury. M1 markers (CD86, inducible nitric oxide synthase, interleukin-1β) and M2 markers (CD206, arginase-1, interleukin-10) were increased after BCNI in the MPG, with the M1/M2 index above 1.0 indicating that more M1 than M2 macrophages were recruited to the MPG. Protein expression of the M1 macrophage marker (inducible nitric oxide synthase) was increased in MPGs after BCNI. However, the protein amount of M2 macrophage markers (arginase-1) remained unchanged. Immunohistochemical characterization demonstrated predominant increases in M1 (CD68+CD86+) macrophages in the MPG after BCNI. ConclusionThese results suggest that an increase in M1 macrophage infiltration of the MPG after BCNI is associated with impaired neurogenically mediated erectile tissue physiology ex vivo and thus has significant implications for cavernous nerve axonal repair. Future studies are needed to demonstrate that inhibition of M1 macrophage recruitment prevents erectile dysfunction after CNI.

061 Stromal Derived Factor-1 Penile Injections Improve Erectile Function Preservation following Nerve Crush Injury by Enhancing Stem Cell Recruitment to the Major Pelvic Ganglion

061 Stromal Derived Factor-1 Penile Injections Improve Erectile Function Preservation following Nerve Crush Injury by Enhancing Stem Cell Recruitment to the Major Pelvic Ganglion

RhoA/ROCK activation in major pelvic ganglion mediates caspase-3 dependent nitrergic neuronal apoptosis following cavernous nerve injury

RhoA/ROCK activation in major pelvic ganglion mediates caspase-3 dependent nitrergic neuronal apoptosis following cavernous nerve injury

Establishment of invitro model of erectile dysfunction for the study of high-glucose-induced angiopathy and neuropathy.

Penile erection requires complex interaction between vascular endothelial cells, smooth muscle cells, pericytes, and autonomic nerves. Diabetes mellitus is one of the most common causes of erectile dysfunction (ED) and multiple pathogenic factors, such as cavernous angiopathy and autonomic neuropathy, are associated with diabetic ED. Although a variety of animal models of diabetic ED play an important role in understanding pathophysiologic mechanisms of diabetes-induced ED, these animal models have limitations for addressing the exact cellular or molecular mechanisms involved in ED. Therefore, we established an invitro model of ED for the study of high-glucose-induced angiopathy and neuropathy. We successfully isolated and cultivated mouse cavernous endothelial cells (MCECs) and mouse cavernous pericytes (MCPs). The cells were exposed to the normal-glucose (5mmoL) or high-glucose (30mmoL) condition for 48h. In vitro matrigel assay revealed impairments in tube formation in primary cultured MCECs or MCPs exposed to high-glucose condition. To study cellular interaction between MCECs and MCPs, co-culture systems including indirect contact, indirect non-contact, and direct mixed co-culture system, were established. We observed impaired tube formation and increased permeability in MCECs-MCPs co-culture exposed to high-glucose condition. To evaluate the effect of high-glucose on neurite sprouting, the mouse major pelvic ganglion (MPG) tissue was harvested and cultivated in matrigel. Neurite outgrowth and nNOS-positive nerve fibers were significantly lower in MPG tissues exposed to the high-glucose condition than in the tissues exposed to the normal-glucose condition. We believe that invitro model of ED will aid us to understand the role of each cellular component in the pathogenesis of diabetic ED, and also be a useful tool for determining the efficacy of candidate therapeutics targeting vascular or neuronal function. This model would present a new avenue for drug discovery and development of novel therapeutic modalities for erectile dysfunction.

Effectiveness of Intracavernous Delivery of Recombinant Human Hepatocyte Growth Factor on Erectile Function in the Streptozotocin-Induced Diabetic Mouse

IntroductionDiabetic erectile dysfunction is a disease mostly of vascular origin and men with diabetic erectile dysfunction respond poorly to oral phosphodiesterase-5 inhibitors. Hepatocyte growth factor (HGF) is a pleiotropic factor that plays an essential role in the regulation of cell proliferation, survival, and angiogenesis. AimTo determine the effectiveness of recombinant human (rh)-HGF in restoring erectile function in diabetic mice. MethodsFour groups of mice were used: control non-diabetic mice and streptozotocin-induced diabetic mice receiving two successive intracavernous injections of phosphate buffered saline (days −3 and 0), a single intracavernous injection of rh-HGF (day 0), or two successive intracavernous injections of rh-HGF (days −3 and 0). We also examined the effect of rh-HGF in primary cultured mouse cavernous endothelial cells and in major pelvic ganglion culture in vitro, which was incubated under a normal-glucose (5 mmol/L) or a high-glucose (30 mmol/L) condition. Main Outcome MeasuresTwo weeks after treatment, we measured erectile function by electrical stimulation of the cavernous nerve and the penis was harvested for histologic studies. ResultsRepeated intracavernous injections of rh-HGF protein induced significant restoration of erectile function in diabetic mice (89–100% of control values), whereas a single intracavernous injection of rh-HGF protein elicited modest improvement. Rh-HGF significantly induced phosphorylation of its receptor c-Met, increased the content of endothelial cells and smooth muscle cells, and decreased the generation of reactive oxygen species (superoxide anion and peroxynitrite) and extravasation of oxidized low-density lipoprotein in diabetic mice. Under the high-glucose condition, rh-HGF protein also promoted tube formation in mouse cavernous endothelial cells and enhanced neurite sprouting in major pelvic ganglion culture in vitro. ConclusionThe dual angiogenic and neurotrophic effects of HGF could open a new avenue through which diabetic erectile dysfunction can be treated.