Dual effect of chitosan activated platelet rich plasma (cPRP) improved erectile function after cavernous nerve injury.

BACKGROUND: The intracavernosal (IC) injection of chitosan activated platelet rich plasma (cPRP) has shown to improve the erectile dysfunction in cavernous nerve injury rat model. However, the action target of PRP in improving neurogenic erectile dysfunction remains unclear. We aimed to determine the effect of cPRP action at early stage that further mediates its effect on erectile function (EF) recovery in the bilateral cavernous nerve crushing (BCNC) injury rat model. METHODS: Fifty-four rats were randomly divided into two equal groups: intracavernosal ( IC) injection of saline after BCNC (group 1) and IC injection of cPRP after BCNC (group 2). Five animals in each group were euthanized at 3, 7 and 14 day (d) post-injection, and the tissues were harvested to conduct transmission electron microscopy and histological assays. Six animals in each group were used to determine the recovery of EF at 14 and 28 d post-injury. RESULTS: IC injections of cPRP increased all EF parameters at 28 d and 14 d post-injury (p < 0.05). cPRP injections simultaneously prevented the loss of neuronal nitric oxide synthase-positive neurons (p < 0.05) and nerve fibers (p < 0.05) in the major pelvic ganglion and cavernous nerve (CN), respectively, compared with saline injections. This simultaneous accelerated the regeneration of myelinated axons of the CN, reduced apoptosis, and enhanced the proliferation of the corporal smooth muscle cells at an earlier stage. CONCLUSION: These results suggest that the application of cPRP was beneficial to restore EF via neuroprotective and tissue-protective effects at early stage.

Specific Impacts of Ketamine on Bladder Dysfunction and Associated Histological Alterations in Rats-A Time Course Validation through Transmission Electron Microscopy.

This study explored the specific effects of ketamine on bladder function followed by a sequence of histological changes in a rat bladder at fixed time course intervals. The rats were grouped into normal control and experimental animals, and ketamine (100 mg/kg/day) was administrated to the experimental animals for 2, 4, and 8 weeks, respectively; similarly, the control animals received saline. All animals were evaluated for bladder function and histological responses to the treatment. Ultrastructural changes were observed by transmission electron microscopy (TEM). The results showed progressive bladder dysfunctions with hyperactive bladder conditions according to the time course and frequency of exposure to ketamine. Significantly, decreased inter contraction intervals, residual urine volume, peak micturition pressure, and increased micturition frequency were observed. Bladder histology results revealed substantial inflammation and comprehensive submucosa edema in week 2 and 4 rats along with fibrosis and significant bladder detrusor hypertrophy in week 8 rats. TEM analysis revealed bladder wall thickening, deformed blood vessels, detrusor hypertrophy, wobbled gap junction, and barrier dysfunction at different time course levels in experimental animals. These results provided a profound knowledge about the prognosis and step-by-step pathophysiology of the disease, which might help in developing new therapeutic interventions.

Intracavernous Injection of Platelet-Rich Plasma Therapy Enhances Erectile Function and Decreases the Mortality Rate in Streptozotocin-Induced Diabetic Rats.

Erectile dysfunction (ED) is an agonizing complication of diabetes mellitus (DM) and it is challenging to treat ED in DM patients. Platelet-rich plasma (PRP) is a unique therapeutic strategy comprising intrinsic growth factors. An attempt was made to explore the potentiality of the PRP treatment in DM-induced ED rats in various groups (control, DM-non-ED, DM-ED, and DM-ED treated with PRP). Streptozotocin (STZ) was used to induce DM in rats. The blood glucose levels of the DM rats were maintained at >300 mg/dl. In the 18-week experiment, survival rate, body weight, intracavernous pressure (ICP) variations, and arterial blood pressure were analyzed. The tissue restoration results were validated by histological, immunofluorescence, and transmission electron microscopic analysis. PRP treatment of DM-ED rats significantly increased all parameters of erectile function compared to pre-treatment of PRP and DM-ED treated with vehicle. The histological results revealed that PRP treatment substantially enhanced the regeneration of myelinated nerves and decreased the atrophy of corporal smooth muscle. Notably, the PRP treatment immensely enhanced the survival rate in post-surgery DM-ED rats. These results indicated certain benefits of PRP treatment in delaying damage and preventing post-surgery complications in DM patients. Hence, PRP treatment is a novel multifactorial strategy for DM-ED patients.

CXCL5 Cytokine Is a Major Factor in Platelet-Rich Plasma's Preservation of Erectile Function in Rats After Bilateral Cavernous Nerve Injury.

BACKGROUND: The neuro-protective and tissue-protective properties of platelet-rich plasma (PRP) have been demonstrated through treating bilateral cavernous nerve (CN) injury in rats, although the underlying mechanisms have not been fully clarified. AIM: To determine factors released from PRP and explore their role in mediating preservation of erectile function (EF) in a rat model of CN injury. METHODS: Male Sprague-Dawley rats (aged 10 weeks) were used in this study. 6 rats were used to obtain blood for PRP and whole plasma preparation. We probed samples using a cytokine antibody array and performed enzyme-linked immunosorbent assay (ELISA). We determined the expression patterns of C-X-C motif chemokine ligand 5 (CXCL5) and receptors in the major pelvic ganglion (MPG) and corpus cavernosum via immunostaining. 32 rats were divided into 4 groups based on the type of injection received: (i) sham, (ii) vehicle, (iii) 400 µL of PRP, and (iv) 30 ng/kg of CXCL5. Groups 2-4 were subjected to bilateral CN crush (BCNC) injury. 4 weeks later, EF was assessed by CN electrostimulation, and CNs and penile tissue were collected for histological analysis. OUTCOME: Cytokine antibody array, ELISA, erectile response, and immunofluorescence staining readings. RESULTS: The PRP contained high levels of CXCL5. MPG neurons expressed CXCL5 and CXCR2. PRP intracavernous injection stabilized CXCR2 and increased CXCL5 expression in the MPG after BCNC, thus enhancing neuroprotection. CXCL5 injection improved BCNC-induced erectile dysfunction by preventing smooth muscle atrophy. CLINICAL IMPLICATIONS: The therapeutic efficacy of PRP in CN injury-induced erectile dysfunction may arise from the synergy among multiple biomolecules. Our study serves as a basis for future studies on PRP formulation to provide safe and effective medications for the maintenance of EF after radical prostatectomy in patients with prostate cancer. STRENGTHS & LIMITATIONS: A strength of our study is that our model was able to isolate the role of cytokines, specifically CXCL5, as part of the mechanism responsible for PRP's protective properties. However, the rat cytokine array provided limited experimental targets. The rats used were not at the age corresponding to prostate cancer patients in clinical settings. Our study did not explore CXCL5 blocking in the PRP group. Finally, the main protein quantification results by western blotting were hampered because of small tissue samples. CONCLUSIONS: This study provides evidence for the role of CXCL5 and CXCR2 as mediators of PRP effects in the preservation of EF after CN injury. Wu YN, Liao CH, Chen KC, et al. CXCL5 Cytokine Is a Major Factor in Platelet-Rich Plasma's Preservation of Erectile Function in Rats After Bilateral Cavernous Nerve Injury. J Sex Med 2021;18:698-710.

B6 Mouse Strain: The Best Fit for LPS-Induced Interstitial Cystitis Model.

Interstitial cystitis (IC) is a chronic inflammatory disease characterized by bladder pain and increased urinary frequency. Although the C57BL/6J (B6) and FVB/NJ (FVB) mouse strains are commonly used as animal models for studies involving the urinary system, few reports have compared their lower urinary tract anatomy, despite the importance of such data. Our study aimed to characterize bladder function changes in FVB and B6 mouse strains with lipopolysaccharide (LPS)-induced IC, to understand mouse model-based bladder research. The bladder function parameters were measured by cystometrogram. Histological assay was examined by hematoxylin and eosin stain, Masson's trichrome stain, and immunofluorescence staining. Results indicated that the two strains in the control group exhibited different bladder structures and functions, with significant anatomical differences, including a larger bladder size in the FVB than in the B6 strain. Furthermore, cystometry tests revealed differences in bladder function pressure. LPS-treated B6 mice presented significant changes in peak pressure, with decreased intercontraction intervals; these results were similar to symptoms of IC in humans. Each strain displayed distinct characteristics, emphasizing the care required in choosing the appropriate strain for bladder-model studies. The results suggested that the B6 mouse strain is more suitable for IC models.

Chlorogenic Acid Intravesical Therapy Changes Acute Voiding Behavior of Systemic Lipopolysaccharide Inflammation-Induced Cystitis Bladder in Mice.

This study explores the potential efficacy of chlorogenic acid (CGA) in mitigating lipopolysaccharide (LPS)-induced cystitis in a mice model. C57BL/6J mice were divided into four groups: normal control (NC), LPS, LPS + low CGA, and LPS + high CGA. Evaluation methods included cystometrogram (CMG), histopathological, western blot, and immunohistological analysis. In the LPS group, CMG revealed abnormal voiding behavior with increased micturition pressure, voided volume (VV), and decreased voided frequency. Low CGA treatment in LPS mice demonstrated improved micturition pressure and inter-contraction intervals (ICI). However, high CGA treatment exhibited prolonged ICI and increased VV, suggesting potential adverse effects. Histological analysis of LPS-treated mice displayed bladder inflammation and interstitial edema. Low CGA treatment reduced interstitial edema and bladder inflammation, confirmed by Masson's trichrome staining. Western blotting revealed increased cytokeratin 20 (K20) expression in the low CGA group, indicating structural abnormalities in the bladder umbrella layer after LPS administration. In conclusion, low CGA treatment positively impacted voiding behavior and decreased bladder edema and inflammation in the LPS-induced cystitis mice model, suggesting its potential as a supplement for inflammation cystitis prevention. However, high CGA treatment exhibited adverse effects, emphasizing the importance of dosage considerations in therapeutic applications.

Insight into SLC9A3 deficiency-mediated micturition dysfunction caused by electrolyte imbalance.

BACKGROUND: Solute carrier family nine isoform 3 (SLC9A3) is an Na+/H+ exchanger that regulates Ca2+ homeostasis. SLC9A3 is largely involved in the transepithelial absorption of Na+/H+ and frequently functions in pair with a Cl-/HCO3- exchanger. OBJECTIVE: To investigate the impact and pathophysiological mechanisms of long-term SLC9A3 deficiency on lower urinary tract symptoms (LUTS) in a mouse model MATERIALS AND METHODS: Slc9a3 knockout and wild-type mice (average >6 months) were used. The effects of SLC9A3 depletion on bladder and urethral functions and effectiveness of voiding were assessed using a cystometrogram (CMG). Histology, blood electrolytes, and gene expression were also analyzed. RESULTS: The SLC9A3-deficient mice had smaller gross bladders than the wild-type mice. The CMG analysis revealed normal peak micturition pressure, higher threshold pressure, short intercontraction interval, less voided volume, and poor compliance in the SLC9A3-deficient mice, similar to clinical LUTS. Histological analysis revealed loose detrusor muscle and loss of transformability of the urothelium in the SLC9A3-deficient mice. Masson's trichrome analysis revealed severe collagen deposition in the detrusor muscle. Immunofluorescence staining also demonstrated a significant decrease in cytokeratins 5 and 20. Gene and protein expression analyses confirmed that SLC9A3 does not act directly on bladder tissue. Homeostasis was correlated with bladder dysfunction in the SLC9A3-deficient mice. DISCUSSION: Fibrosis and collagen deposition in the bladder of the SLC9A3-deficient mice is due to bladder inflammation because of decreased blood flow and deregulated systemic homeostasis. Long-term SLC9A3 depletion causes progressive bladder dysfunction, similar to human LUTS. CONCLUSION: Electrolyte imbalance causes SLC9A3 deficiency-mediated progressive micturition dysfunction.

Effects of platelet-rich plasma glue placement at the prostatectomy site on erectile function restoration and cavernous nerve preservation in a nerve-sparing prostatectomy rat model.

BACKGROUND: Despite the widespread use of nerve-sparing prostatectomy techniques, the incidence of post-operative erectile dysfunction (ED) remains high. Early intracavernous (IC) injection of platelet-rich plasma (PRP) after nerve crushing improves erectile function (EF) in rats by promoting cavernous nerve (CN) regeneration and preventing structural changes in the corpus cavernosum. However, the neuroprotective effects of the in situ application of PRP glue in rats after CN-sparing prostatectomy (CNSP) remain unclear. AIM: This study aimed to investigate the effects of PRP glue treatment on EF and CN preservation in rats after CNSP. METHODS: After prostatectomy, male Sprague-Dawley rats were treated with PRP glue, IC PRP injection, or their combination. The intracavernous pressure (ICP), mean arterial pressure (MAP), and CN preservation status in the rats were evaluated after 4 weeks. Results were corroborated using histology, immunofluorescence, and transmission electron microscopy. RESULTS: The PRP glue-treated rats showed 100% CN preservation and significantly higher ICP responses (the ratio of maximum ICP to MAP (0.79 ± 0.09)) than the CNSP rats (the ratio of maximum ICP to MAP (0.33 ± 0.04)). PRP glue also significantly increased neurofilament-1 expression, indicating its positive effect on the CNs. Furthermore, this treatment significantly increased the expression of α-smooth muscle actin. Electron micrographs revealed that PRP glue preserved the myelinated axons and prevented atrophy of the corporal smooth muscle by maintaining the adherens junctions. CONCLUSIONS: These results indicate that PRP glue is a potential solution for EF preservation by neuroprotection in patients with prostate cancer who are likely to undergo nerve-sparing radical prostatectomy.

Consensus of Experts on the Treatment of Sexual Dysfunction after Surgery for Prostate Cancer in Taiwan.

According to the Taiwan Cancer Report, in 2018, prostate cancer was one of the top five cancers reported in men. Each year, many patients with prostate cancer undergo radical prostatectomy (RP) therapy. One of the most common RP complications is erectile dysfunction (ED). Although consensus guidelines for the management of sexual dysfunction after prostate cancer surgery have been developed for many Western and Asian countries, no such clinical practice guidelines have been developed for Taiwan. The consensus opinions expressed in this article were discussed by numerous experienced physicians in Taiwan, based on both existing international guidelines and their individual experiences with clinical trials and providing advice to clinical physicians on how to inform patients of the risk of ED prior to surgery. This review also discusses how recovery and rehabilitation may be affected by socioeconomic status, the existence of an intimate relationship, comorbidities, or the need for cancer adjuvant therapy and how to determine rehabilitation goals and provide appropriate treatments to assist in the recovery of both short- and long-term sexual function.

The neuroprotective effect of platelet-rich plasma on erectile function in bilateral cavernous nerve injury rat model.

INTRODUCTION: Neurogenic erectile dysfunction resulting from cavernous nerve (CN) injury is a major complication caused by radical prostatectomy. The use of platelet-rich plasma (PRP) on the nerve-injured site has shown promising results for the nerve regeneration. However, the effects of PRP injection in corpus cavernosum after bilateral CN injury have never been investigated. AIM: To assess the neuroprotective effect of PRP injection in corpus cavernosum after bilateral CN injury. METHODS: Male Sprague-Dawley rats were randomly divided into three groups: Group I underwent sham operation, while the remaining two groups underwent bilateral CN crush. Crush injury groups were treated at the time of injury with an application of PRP or normal saline only injection in the corpus cavernosum, respectively. Four weeks later, erectile function (EF) was assessed by CN electrosimulation, and CNs as well as penile tissue were collected for histology. MAIN OUTCOME MEASURES: Intracavernous pressure (ICP) monitored during electrical stimulation of CNs; myelinated axons number of CNs and dorsal penile nerve; collagen type change, number of apoptotic cells, and mRNA expression of caspase-3 and transforming growth factor-ß1 (TGF-ß1) in the corpus cavernosum. RESULTS: Four weeks after surgery, in the vehicle-only group, the functional evaluation showed a lower mean maximal ICP than that in the sham group (P < 0.05). PRP treatments resulted in significant recovery of EF, as compared with the vehicle-only group (P < 0.05). Histologically, the PRP-treated group had a significant preservation of myelinated axons of CNs compared with the vehicle-only group (P < 0.05) and reduced the apoptotic index. The mRNA expression of TGF-ß1 in the corpus cavernosum tissue was significantly decreased in the PRP group compared with the vehicle-only group (P < 0.05). CONCLUSIONS: PRP injection in the corpus cavernosum increased the number of myelinated axons and facilitated recovery of EF in the bilateral CN injury rat model.

Smooth Muscle Progenitor Cells Preserve the Erectile Function by Reducing Corporal Smooth Muscle Cell Apoptosis after Bilateral Cavernous Nerve Crush Injury in Rats.

Radical prostatectomy causes erectile dysfunction (ED) and irreversible morphologic changes, including induction of endothelial and smooth muscle cell (SMC) apoptosis in the corpus cavernosum (CC). The injection of smooth muscle progenitor cells (SPCs) thickens the vascular intima and has demonstrated therapeutic benefit in cardiovascular disease animal. Herein, we investigated the effect of SPCs on the recovery of erectile function (EF) in rat models with bilateral cavernous nerve (CN) injury. Twenty-four male Sprague-Dawley rats were randomized into sham, vehicle only, or SPC treatment groups. Rats in the SPC treatment and vehicle groups were subjected to bilateral CN injury before intracavernosal injection. Intracavernosal injections of SPCs increased all EF parameters at day 28 after injury and simultaneously reduced apoptosis of the SMCs. Ultrastructural analysis revealed that SPCs maintained the integrity of the CC by preserving the structure of the adherens junctions. Tracking transplanted SPCs labeled with EdU showed that transplanted SPCs remained in the CC 28 days after treatment. Intracavernosal SPC injection restored EF after bilateral CN injury by reducing SMC apoptosis, which favored the maintenance of the structure of adherens junctions and regulated the stability of corporal vessels. These findings demonstrate the therapeutic potential of SPCs for treating ED in humans.

SLC9A3 Affects Vas Deferens Development and Associates with Taiwanese Congenital Bilateral Absence of the Vas Deferens.

BACKGROUND: The pathophysiology of Taiwanese congenital bilateral absence of the vas deferens (CBAVD) is different from that in Caucasians. In particular, major cystic fibrosis transmembrane conductance regulator (CFTR) mutations and cystic fibrosis are absent in the former. Instead, deficiency in solute carrier family 9 sodium/hydrogen exchanger isoform 3 (SLC9A3) may play a role by generating obstructive azoospermia and degraded epithelial structure in the reproductive tract. OBJECTIVES: The objective of the study was to test whether SLC9A3 variants cause Taiwanese CBAVD. MATERIALS AND METHODS: Six-month-old Slc9a3 -/-male mice were used to evaluate the effect of long-term SLC9A3 loss on the reproductive system. A case-control cohort of 29 men with CBAVD and 32 fertile men were genotyped for SLC9A3 variants. RESULTS: SLC9A3 was expressed and localized in the apical border of the epithelium of human vas deferens and glandular epithelium of the seminal vesicle. SLC9A3 deficiency specifically induces atrophy of vas deferens and unfolding of seminal vesicle mucosa in mice. Loss of SLC9A3 increased the incidence of CBAVD in humans from 3.1% to 37.9% (p < 0.001). Up to 75.9% of CBAVD patients carry at least one variant in either SLC9A3 or CFTR. DISCUSSION: Our findings build upon previous data associated with CBAVD pathogenesis. Here, we now report for the first time an association between CBAVD and loss of SLC9A3 and propose that specific defects in the reproductive duct due to SLC9A3 variants drive CBAVD development. CONCLUSION: The data implicate loss of SLC9A3 as a basis of Taiwanese CBAVD and highlight SLC9A3 function in reproduction.

Spontaneous Regeneration of Nerve Fiber and Irreversibility of Corporal Smooth Muscle Fibrosis After Cavernous Nerve Crush Injury: Evidence From Serial Transmission Electron Microscopy and Intracavernous Pressure.

OBJECTIVE: To determine the pathophysiological progresses following bilateral cavernous nerve crushing injury, as an index for a treatment point and establishment of adequate treatment strategies for neurogenic erectile dysfunction. MATERIALS AND METHODS: Thirty-six rats were assigned to 1 of 6 groups, and bilateral cavernous nerve crushing or sham surgery was performed. Functional testing and ultrastructural analyses were performed immediately and at 7, 14, 21, and 28 days after the cavernous nerve (CN) injury (n = 6). RESULTS: Intracavernos pressure lowered progressively from 7 days to 14 days post-injury, and histologic staining revealed that the number of neuronal nitric oxide synthase-positive nerve fibers on the dorsal penile nerve decreased significantly and progressively from 7 days until 21 days post-injury. Furthermore, ultrastructural analyses revealed axon loss and demyelination of the CN at 7 and 14 days post-injury. However, it is followed by partial spontaneous recovery of erectile function and regeneration of the CN at 28 days post-injury, suggesting that these time points may be useful for evaluating the effects of drug treatments. Furthermore, we found that CN injury-induced damage to corporal smooth muscle cells was irreversible; therefore, focusing on protecting the corpus cavernosum from apoptosis may be more important than nerve protection when assessing treatment mechanisms in the CN injury model. CONCLUSION: Our study makes a significant contribution to the human diagnostic pathology literature because it describes characteristics of relevant tissue in the rat and provides information regarding time points that may be useful for future studies of pathologic mechanisms or treatment evaluations.

nNOS-positive minor-branches of the dorsal penile nerves is associated with erectile function in the bilateral cavernous injury model of rats.

The changes in neuronal nitric oxide synthases (nNOS) in the dorsal penile nerves (DPNs) are consistent with cavernous nerve (CN) injury in rat models. However, the anatomical relationship and morphological changes between the minor branches of the DPNs and the CNs after injury have never been clearly explored. There were forty 12 week old male Sprague-Dawley rats receiving bilateral cavernous nerve injury (BCNI). Erectile function of intracavernous pressure and mean arterial pressure were measured. The histology and ultrastructure with H&E stain, Masson's trichrome stain and immunohistochemical stains were applied on the examination of CNs and DPNs. We demonstrated communicating nerve branches between the DPNs and the CNs in rats. The greatest damage and lowest erectile function were seen in the 14th day and partially recovered in the 28th day after BCNI. The nNOS positive DPN minor branches' number was significantly correlated with erectile function. The sub-analysis of the number of nNOS positive DPN minor branches also matched with the time course of the erectile function after BCNI. We suggest the regeneration of the DPNs minor branches would ameliorate the erectile function in BCNI rats.

Dual Roles of 17-ß Estradiol in Estrogen Receptor-dependent Growth Inhibition in Renal Cell Carcinoma.

BACKGROUND: It has been proposed that 17-ß-estradiol (E2) activates estrogen receptor and inhibits renal cell carcinoma (RCC) growth. In the present study we explored the role of E2 and ER in the regulation of RCC growth. MATERIALS AND METHODS: The RCC cell line ACHN was treated by E2 combining with E2 antagonist Fulvestrant or ER knockdown, and cell growth was monitored. Quantitative phosphoproteomics was applied to study the E2 regulated non-genomic phosphorylation changes. Western blotting, immunofluorescence microscopy, and apoptosis assays were used for validation. RESULTS: E2 induced ER-dependent growth inhibition in RCC cell lines. Quantitative phosphoproteomics revealed that E2 induced both apoptosis and autophagy. Cellular apoptosis was confirmed by altered mitochondrial membrane potential, and ER-dependent autophagosome formation was also found. CONCLUSION: Our data revealed the potential dual roles of E2 in regulating RCC growth via autophagy and apoptosis pathways.

Optimization of platelet-rich plasma and its effects on the recovery of erectile function after bilateral cavernous nerve injury in a rat model.

Platelet-rich plasma (PRP) containing autologous growth factors is applied in regenerative medicine, but the lack of an optimized PRP preparation protocol causes unstable therapeutic effects. The aim of this study was to optimize the PRP preparation method and compare the effects of PRP from different preparation methods in restoration of erectile function in a rat model. The in vivo experiments used Sprague-Dawley male rats (n = 24), which were randomly divided into four groups of equal numbers: group I underwent sham operation, while the remaining three groups underwent bilateral CN crush. Crush injury groups were treated at the time of injury with an application of general PRP, optimized PRP [with the largest amount of platelet-derived growth factor (PDGF)-AB] or normal saline-only injection in the corpus cavernosum, respectively. Four weeks later, erectile function was assessed by CN electrosimulation, and penile tissue was collected for histology. Results demonstrated that in the PRP group prepared with the ACD-A anticoagulant, chitosan and incubated at -20°C for 15 days had the largest amount of PDGF-AB and showed a synergistic effect on release (p < 0.05). Functional outcome measurement and immunofluorescence staining for the dorsal nerve revealed that improvement after bilateral CN injury occurred in the optimized PRP group (p < 0.05). It was concluded that optimized PRP with a high level of growth factors was more stable, and its injection into the corpus cavernosum facilitated recovery of erectile function. Copyright © 2013 John Wiley & Sons, Ltd.

Effect of Ginkgo biloba Extract (EGb-761) on Recovery of Erectile Dysfunction in Bilateral Cavernous Nerve Injury Rat Model.

OBJECTIVE: To investigate whether the therapeutic effect of Ginkgo biloba extract (GBE) in a rat model can improve erectile dysfunction after bilateral cavernous nerve injury. METHODS: Forty-three male Sprague-Dawley rats underwent cavernous nerve crush injury and were randomized into 4 groups, including: vehicle only, high-dose GBE, medium-dose GBE, and low-dose GBE. Eight animals underwent sham operation. Four weeks later, erectile function was assessed by cavernous nerve electrostimulation, and penile tissue was collected for histologic analysis. RESULTS: Significant recovery of erectile function was observed in the high-dose GBE group in a dose-dependent manner as compared with the vehicle-only group (P <.001). The high-dose GBE group had a significant increase in neurofilament-1 expression (P <.001), preservation of neural nitric oxide synthase nerve fibers of the dorsal penile nerve (P <.05), and increased smooth muscle cell content (P <.001) compared with the vehicle-only group. In addition, high-dose GBE markedly augments the smooth muscle-to-collagen ratio (P <.05) and reduces the apoptotic index. CONCLUSION: Administration of GBE increases neuron survival and preserves the neural nitric oxide synthase nerve fiber and contents of the corpus cavernosum after bilateral cavernous nerve injury. These implications indicate the beneficial effects of GBE use in the repair of the cavernous nerve and recovery of erectile function after radical prostatectomy.

The additive erectile recovery effect of brain-derived neurotrophic factor combined with vascular endothelial growth factor in a rat model of neurogenic impotence.

OBJECTIVE: To test the hypothesis that combined intracavernosal injection with vascular endothelial growth factor (VEGF) with adeno-associated virus-mediated brain-derived neurotrophic factor (AAV-BDNF) synergistically facilitates the neural regeneration and erectile function after cavernosal nerve injury. MATERIALS AND METHODS: Forty Sprague-Dawley male rats were randomly divided into five equal groups: eight had a sham operation while 32 had bilateral cavernosal nerve freezing followed by an immediate intracavernosal injection with either phosphate-buffered saline (PBS), VEGF, AAV-BDNF, or AAV-BDNF + VEGF. Erectile function was assessed by cavernosal nerve electrostimulation at 3 months, and samples of the major pelvic ganglia and penile tissue were evaluated histologically. RESULTS: In this animal model of impotence from nerve injury, the recovery of erectile function was greatest in those receiving AAV-BDNF + VEGF; the mean (sd) maximal intracavernosal pressure in this group was 87.2 (20.78) cmH2O, compared with 37.3 (11.39) for VEGF alone and 49.8 (29.58) for AAV-BDNF alone. No erectile dysfunction was identified in the sham group, with a pressure of 100.7 (22.70) cmH2O, while all treatment groups significantly outperformed the PBS (control) group, at 29.3 (13.52) cmH2O. Furthermore, all animals receiving monotherapy or combined treatment had more NADPH-diaphorase-positive nerve fibres than controls but less than in the sham group. CONCLUSION: Bilateral cavernosal nerve freezing causes erectile dysfunction with accompanying neurological changes. Intracavernosal injection with either VEGF or AAV-BDNF alone enhances nerve regeneration, with combined therapy (VEGF and AAV-BDNF) promoting neural and erectile recovery additively.

Vascular endothelial growth factor induces IP-10 chemokine expression.

We have previously shown that intracavernous injection of vascular endothelial growth factor (VEGF) improved the recovery of erectile function in an arteriogenic impotence rat mode. We wished to identify genes that are affected by VEGF treatment in the penis. Specifically we examined the induction of IP-10 chemokine. Male rats were subjected to pudendal arterial ligation or sham operation. They were then treated with intracavernous injection of 4 microg of VEGF in phosphate-buffered saline (PBS) or PBS alone. At 6 and 24 h after treatment, the erectile tissue was then harvested for RNA isolation. The isolated RNA was used for microarray and RT-PCR analyses. Cultured rat cavernous smooth muscle cells (CSMC) were treated with VEGF and then subjected to RT-PCR analysis. Cultured human CSMC were treated with VEGF and then subjected to ELISA analysis. Microarray analysis detected IP-10 as an abundantly induced message in 6-h VEGF-treated tissues. This was further confirmed by RT-PCR analysis. Using cultured rat CSMC, induction of IP-10 mRNA was detectable in 1 and 2 h, but not 24 h, VEGF-treated cells. Induction of IP-10 at the protein level was observed with cultured human CSMC. Secretion of IP-10 into culture medium peaked at 4 h after treatment of human CSMC with 10 ng/ml of VEGF. Optimal VEGF dosage for IP-10 induction was 50 ng/ml when assayed with cells that were treated for 8 h.