Effects of exercise training on patients with lung cancer who underwent lung resection: a meta-analysis.

BACKGROUND: The efficacy of exercise training in patients with lung cancer after lung resection has not been well established yet. Therefore, we performed a meta-analysis to investigate the efficiency of exercise training in patients with lung cancer after lung resection. METHODS: Several databases were searched for eligible randomised controlled trials (RCTs). The primary outcome was quality of life, and the secondary outcomes included 6-min walk distance (6MWD), forced expiratory volume in 1 s (FEV1) and postoperative complications (POCs). Weighted mean differences (WMDs) and relative risks (RRs) with 95% confidence intervals (CIs) were calculated by random-effects model. RESULTS: Six RCTs involving 438 patients were enrolled in this meta-analysis. The pooled WMDs of the scores were 2.41 (95% CI = -5.20 to 10.02; P = 0.54) and -0.46 (95% CI = -20.52 to 19.61; P = 0.96) for the physical and mental components of the 36-item short-form scale, respectively. The pooled WMDs were 23.50 m (95% CI = -22.04 to 69.03; P = 0.31) for 6MWD and 0.03 L (95% CI = -0.19 to 0.26; P = 0.76) for FEV1. Finally, the pooled RRs were 0.79 (95% CI = 0.41 to 1.53; P = 0.49) for POCs. CONCLUSIONS: Insufficient evidence is available to support the efficacy of exercise training in patients with lung cancer after lung resection. Further studies must confirm our findings and investigate the long-term effects of exercise training on patients with lung cancer following lung resection.

Intracavernous delivery of stromal vascular fraction restores erectile function through production of angiogenic factors in a mouse model of cavernous nerve injury.

INTRODUCTION: Erectile dysfunction (ED) is a major complication of radical prostatectomy. Men with radical prostatectomy-induced ED respond less positively to oral phosphodiesterase-5 inhibitors. AIM: The study aims to examine whether and how stromal vascular fraction (SVF) restores erectile function in mice with cavernous nerve injury (CNI). METHODS: Twelve-week-old male C57BL/6J mice were used and the animals were distributed into five groups: sham operation group and CNI group receiving a single intracavernous injection of phosphate-buffered saline (PBS) or SVF (1 × 10(4) , 1 × 10(5) , or 3 × 10(5) cells/20 µL, respectively). SVF was isolated from epididymal adipose tissues of green fluorescence protein transgenic mice. MAIN OUTCOME MEASURES: Two weeks after injection, erectile function was measured by cavernous nerve stimulation. The penis was stained with antibodies to platelet/endothelial cell adhesion molecule-1, phosphohistone H3, and phosphorylated endothelial nitric oxide synthase (phospho-eNOS). We also performed Western blot for angiopoietin-1 (Ang-1), vascular endothelial growth factor-A, hepatocyte growth factor, phospho-eNOS, and eNOS in the corpus cavernosum tissue. RESULTS: Local delivery of SVF restored erectile function in a dose-dependent manner in CNI mice. The highest erectile response was noted at a dose of 3 × 10(5) cells, for which the response was comparable with that in the sham operation group. Local delivery of SVF significantly increased the expression of angiogenic factor proteins and induced cavernous endothelial cell proliferation and eNOS phosphorylation compared with that in the PBS-treated CNI group. SVF-induced promotion of cavernous angiogenesis and erectile function was diminished in the presence of soluble antibody to Tie2, a receptor tyrosine kinase of Ang-1. CONCLUSION: Secretion of angiogenic factors from SVF is an important mechanism by which SVF induces cavernous endothelial regeneration and restores erectile function. These findings suggest that cavernous endothelial regeneration by using SVF may represent a promising treatment strategy for radical prostatectomy-induced ED.

Effectiveness of intracavernous delivery of adenovirus encoding Smad7 gene on erectile function in a mouse model of cavernous nerve injury.

INTRODUCTION: Men with erectile dysfunction (ED) respond poorly to oral phosphodiesterase-5 inhibitors following radical prostatectomy. Recent studies have reported that up-regulation of transforming growth factor-ß1 (TGF-ß1) and activation of the Smad signaling pathway play important roles in cavernous fibrosis and in the deterioration of erectile function in a mouse model of cavernous nerve injury (CNI) and in patients with spinal cord injury. The mothers against decapentaplegic homolog 7 (Smad7) is known to inhibit the phosphorylation of Smad2 and Smad3. AIM: To investigate the effectiveness of adenoviruses encoding Smad7 gene (Ad-Smad7) on erectile function in a mouse model of CNI. METHODS: Twelve-week-old C57BL/6J mice were used and distributed into 7 groups: sham operation group, untreated CNI group, and CNI groups receiving a single intracavernous injection of adenovirus encoding LacZ (1 × 10(8) virus particles [vp]/20 µL) or adenovirus encoding Smad7 (Ad-Smad7; 1 × 10(7), 1 × 10(8), 2 × 10(8), or 1 × 10(9) vp/20 µL). MAIN OUTCOME MEASURES: Two weeks after bilateral cavernous nerve crushing and treatment, erectile function was measured by electrical stimulation of the cavernous nerve. The penis was harvested for histologic examinations and Western blot analysis. RESULTS: The highest erectile response was noted in CNI mice treated with Ad-Smad7 at a dose of 1 × 10(8) vp, which reached up to 82-85% of sham control values. Local delivery of Ad-Smad7 significantly decreased endothelial cell apoptosis and the production of extracellular matrix proteins, including plasminogen activator inhibitor-1, fibronectin, collagen I, and collagen IV, and induced endothelial nitric oxide synthase phosphorylation in the corpus cavernosum tissue of CNI mice. CONCLUSION: The adenovirus-mediated gene transfer of Smad7 successfully restored erectile function by enhancing endothelial cell function and through antifibrotic effects. These findings suggest that inhibition of the TGF-ß signaling pathway by use of Smad7 may represent a promising therapeutic strategy for ED induced by radical prostatectomy.

Erectile dysfunction precedes other systemic vascular diseases due to incompetent cavernous endothelial cell-cell junctions.

PURPOSE: Erectile dysfunction is often a harbinger of cardiovascular disease. We sought to gain mechanistic insight at the cellular and molecular levels into why erectile dysfunction precedes the clinical consequences of cardiovascular disease. MATERIALS AND METHODS: Diabetes was induced by intraperitoneal streptozotocin injection in 8-week-old C57BL/6J mice. At 8 weeks after diabetes induction, we determined the expression of endothelial cell-cell junction proteins and vascular endothelial permeability in the penis, heart and hind limb by systemic injection of various vascular space markers (350 Da to 2,000 kDa) or by immunohistochemical staining with antibody to oxidized low density lipoprotein. We also investigated the effect of recombinant Ang1 protein on cavernous endothelial permeability. RESULTS: Alterations in the integrity of the endothelial cell-cell junction, including a decrease in endothelial cell-cell junction proteins and an increase in vascular permeability to fluorescent tracers or oxidized low density lipoprotein, were prominent in the cavernous tissue of diabetic mice. In contrast, no significant changes in endothelial cell-cell junction proteins or vascular permeability were noted in heart or hind limb tissue according to the diabetic condition. Intracavernous injection of Ang1 protein, an anti-permeability factor, significantly decreased cavernous endothelial permeability to oxidized low density lipoprotein by restoring endothelial cell-cell junction proteins in diabetic mice. CONCLUSIONS: The incompetent cavernous endothelial cell-cell junction in the diabetic condition provides an important clue to why erectile dysfunction is highly prevalent and often precedes other systemic vascular diseases.

Expression of the apelin-APJ pathway and effects on erectile function in a mouse model of vasculogenic erectile dysfunction.

INTRODUCTION: Much attention has recently been focused on therapeutic angiogenesis as a treatment for erectile dysfunction (ED). The apelin and apelin receptor (APJ) system is known to cause endothelium-dependent vasodilatation and to be involved in angiogenesis. AIM: To examine the differential expression of apelin and APJ in animal models of vasculogenic ED and to determine whether and how enhancement of apelin-APJ signaling restores erectile function in hypercholesterolemic mice. METHODS: Acute cavernous ischemia was induced in C57BL/6J mice by bilateral occlusion of internal iliac arteries, and chronic vasculogenic ED was induced by feeding a high-cholesterol diet or by intraperitoneal injection of streptozotocin. MAIN OUTCOME MEASURES: Messenger RNA (mRNA) levels of apelin and APJ were determined in cavernous tissue of each vasculogenic ED model by semiquantitative reverse transcriptase-polymerase chain reaction (RT-PCR). We evaluated erectile function by electrical stimulation of the cavernous nerve in hypercholesterolemic mice 1, 3, 7, and 14 days after a single intracavernous injection of apelin protein (5 µg/20 µL). The penis was harvested for histologic examinations and Western blot analysis. RESULTS: The cavernous mRNA expression of apelin and APJ was up-regulated in acute ischemia model and down-regulated in chronic vasculogenic ED models. A significant restoration of erectile function was noted 1 day after injection of apelin protein into the penis of hypercholesterolemic mice; however, erectile function returned to baseline values thereafter. The beneficial effects of apelin on erectile function resulted mainly from an activation of endothelial nitric oxide synthase and increase in nitric oxide bioavailability through reduction in reactive oxygen species-mediated endothelial apoptosis rather than through direct endothelial cell proliferation. CONCLUSION: These findings suggest that apelin-APJ signaling is a potential therapeutic target in the treatment of vasculogenic ED. Further studies are needed to develop a potent agonist for APJ and to determine the role of repeated dosing of apelin on long-term recovery of erectile function.

Effect of intracavernous administration of angiopoietin-4 on erectile function in the streptozotocin-induced diabetic mouse.

INTRODUCTION: Erectile dysfunction (ED) is a highly prevalent complication of diabetes, and the severity of endothelial dysfunction is one of the most important factors in reduced responsiveness to oral phosphodiesterase type 5 inhibitors. AIM: To study the effects of human angiopoietin-4 (Ang-4) protein on erectile function in diabetic mice. METHODS: Diabetes was induced by intraperitoneal injection of streptozotocin into 8-week-old C57BL/6J male mice. At 8 weeks after the induction of diabetes, the animals were divided into four groups: control nondiabetic mice and diabetic mice receiving two successive intracavernous injections of phosphate buffered saline (days -3 and 0), a single intracavernous injection of Ang-4 protein (day 0), or two successive intracavernous injections of Ang-4 protein (days -3 and 0). MAIN OUTCOME MEASURES: One week after treatment, we measured erectile function by electrical stimulation of the cavernous nerve. The penis was harvested and stained with hydroethidine or antibodies to Ang-4, platelet/endothelial cell adhesion molecule-1, and phosphorylated endothelial nitric oxide synthase (eNOS). We also determined the differential expression of Ang-4 in cavernous tissue in the control and diabetic mice. The effect of Ang-4 protein on the phosphorylation of Tie-2, Akt, and eNOS was determined in human umbilical vein endothelial cells (HUVECs) by Western blot. RESULTS: The cavernous expression of Ang-4 was downregulated in diabetic mice; Ang-4 was mainly expressed in endothelial cells. Local delivery of Ang-4 protein significantly increased cavernous endothelial content, induced eNOS phosphorylation, and decreased the generation of superoxide anion and apoptosis in diabetic mice. Ang-4 protein strongly increased the phosphorylation of Tie-2, Akt, and eNOS in HUVECs. Repeated intracavernous injections of Ang-4 induced significant restoration of erectile function in diabetic mice (87% of control values), whereas a single intracavernous injection of Ang-4 protein elicited modest improvement. CONCLUSIONS: Cavernous endothelial regeneration by use of Ang-4 protein may have potential for the treatment of vascular disease-induced ED, such as diabetic ED.

Nerve injury-induced protein 1 (Ninjurin-1) is a novel therapeutic target for cavernous nerve injury-induced erectile dysfunction in mice.

INTRODUCTION: Radical prostatectomy for prostate cancer can not only induce cavernous nerve injury (CNI) but also result in structural changes in the cavernous tissues. Nerve injury-induced protein 1, Ninjurin-1 (Ninj1), is known to be involved in neuroinflammatory processes and to be related to vascular regression during the embryonic period. AIM: The study aims to determine whether and how Ninj1 neutralizing antibody (Ninj1-Ab) restores erectile function in mice with CNI. METHODS: Twelve-week-old C57BL/6J mice were used and distributed into four groups: sham operation group and CNI groups receiving a single intracavernous injection of immunoglobulin G (IgG) control antibody, low-dose Ninj1-Ab (1.0 µg/20 µL), or high-dose Ninj1-Ab (2.5 µg/20 µL). MAIN OUTCOME MEASURES: One week after bilateral cavernous nerve crush, erectile function was measured by electrical stimulation of the cavernous nerve. The penis was harvested for histologic examinations and Western blot analysis. RESULTS: The cavernous expression of Ninj1 protein was upregulated up to 7 days after CNI and returned to baseline levels thereafter. Local delivery of Ninj1-Ab significantly increased penile neuronal nitric oxide synthase and neurofilament contents, induced cavernous endothelial proliferation and phosphorylation of Akt and endothelial nitric oxide synthase, and decreased endothelial cell apoptosis in the CNI mice by upregulating angiopoietin-1 and downregulating angiopoietin-2. High-dose Ninj1-Ab induced profound restoration of erectile function in the CNI mice (91% of sham control values), whereas low-dose Ninj1-Ab elicited partial improvement. CONCLUSION: The dual neurotrophic and angiogenic effects of Ninj1 blockade may provide a good opportunity for treating erectile dysfunction resulting from radical prostatectomy.

Heme-binding protein 1 delivered via pericyte-derived extracellular vesicles improves neurovascular regeneration in a mouse model of cavernous nerve injury.

As a peripheral nerve injury disease, cavernous nerve injury (CNI) caused by prostate cancer surgery and other pelvic surgery causes organic damage to cavernous blood vessels and nerves, thereby significantly attenuating the response to phosphodiesterase-5 inhibitors. Here, we investigated the role of heme-binding protein 1 (Hebp1) in erectile function using a mouse model of bilateral CNI, which is known to promote angiogenesis and improve erection in diabetic mice. We found a potent neurovascular regenerative effect of Hebp1 in CNI mice, demonstrating that exogenously delivered Hebp1 improved erectile function by promoting the survival of cavernous endothelial-mural cells and neurons. We further found that endogenous Hebp1 delivered by mouse cavernous pericyte (MCP)-derived extracellular vesicles promoted neurovascular regeneration in CNI mice. Moreover, Hebp1 achieved these effects by reducing vascular permeability through regulation of claudin family proteins. Our findings provide new insights into Hebp1 as a neurovascular regeneration factor and demonstrate its potential therapeutic application to various peripheral nerve injuries.

Matrigel-based sprouting endothelial cell culture system from mouse corpus cavernosum is potentially useful for the study of endothelial and erectile dysfunction related to high-glucose exposure.

INTRODUCTION: A proper cavernous endothelial cell culture system would be advantageous for the study of the pathophysiologic mechanisms involved in endothelial dysfunction and erectile dysfunction (ED). AIM: To establish a nonenzymatic technique, which we termed the "Matrigel-based sprouting endothelial cell culture system," for the isolation of mouse cavernous endothelial cells (MCECs) and an in vitro model that mimics in vivo situation for diabetes-induced ED. METHODS: For primary MCEC culture, mouse cavernous tissue was implanted into Matrigel and sprouting cells from the tissue were subcultivated. To establish an in vitro model for diabetes-induced ED, the primary cultured MCECs were exposed to a normal-glucose (5 mmoL) or a high-glucose (30 mmoL) condition for 48 hours. MAIN OUTCOME MEASURES: The purity of isolated cells was determined by fluorescence-activated cell sorting analysis. MCECs incubated under the normal- or the high-glucose condition were used for Western blot, cyclic guanosine monophosphate (cGMP) quantification, and in vitro angiogenesis assay. RESULTS: We could consistently isolate high-purity MCECs (about 97%) with the Matrigel-based sprouting endothelial cell culture system. MCECs were subcultured up to the fifth passage and no significant changes were noted in endothelial cell morphology or purity. The phosphorylation of Akt and eNOS and the cGMP concentration were significantly lower in MCECs exposed to high glucose than in those exposed to normal glucose. MCECs exposed to the normal-glucose condition formed well-organized capillary-like structures, whereas derangements in tube formation were noted in MCECs exposed to high glucose. The protein expression of transforming growth factor-ß1 (TGF-ß1) and phospho-Smad2 was significantly increased by exposure to high glucose. CONCLUSION: The Matrigel-based sprouting endothelial cell culture system is a simple, technically feasible, and reproducible technique for isolating pure cavernous endothelial cells in mice. An in vitro model for diabetic ED will be a valuable tool for evaluating the angiogenic potential of novel endogenous or synthetic modulators.

Intracavernous delivery of freshly isolated stromal vascular fraction rescues erectile function by enhancing endothelial regeneration in the streptozotocin-induced diabetic mouse.

INTRODUCTION: Men with diabetic erectile dysfunction (ED) often have severe endothelial dysfunction and respond poorly to oral phosphodiesterase-5 inhibitors. AIM: To examine whether and how freshly isolated stromal vascular fraction (SVF) promotes cavernous endothelial regeneration and restores erectile function in diabetic animals. METHODS: Eight-week-old C57BL/6J mice were used. Diabetes was induced by intraperitoneal injection of streptozotocin. SVF was isolated from epididymal adipose tissues of green fluorescence protein transgenic mice. At 8 weeks after the induction of diabetes, the animals were divided into six groups: controls, diabetic mice, and diabetic mice treated with a single intracavernous injection of phosphate-buffered saline (PBS) or SVF (1 × 10(4) cells, 1 × 10(5) cells, or 2 × 10(5) cells/20 µL, respectively). MAIN OUTCOME MEASURES: Two weeks later, erectile function was measured by cavernous nerve stimulation. The penis was stained with antibodies to CD31, CD34, phosphohistone H3, phospho-endothelial nitric oxide synthase (eNOS), and vascular endothelial growth factor-A (VEGF-A). We also performed Western blot for phospho-eNOS and eNOS, and determined cyclic guanosine monophosphate (cGMP) concentration in the corpus cavernosum tissue. RESULTS: Significant improvement in erectile function was noted in diabetic mice treated with SVF at concentrations of 1 × 10(5) and 2 × 10(5) cells, which reached up to 82% of the control values. Local delivery of SVF significantly increased cavernous endothelial cell proliferation, eNOS phosphorylation, and cGMP expression compared with that in the untreated group and the PBS-treated diabetic group. Intracavernous injection of SVF increased cavernous VEGF-A expression and induced recruitment of CD34(+)CD31(-) progenitor cells. Some SVF underwent differentiation into cavernous endothelial cells. SVF-induced promotion of cavernous angiogenesis and erectile function was abolished in the presence of VEGF-Trap, a soluble VEGF-A neutralizing antibody. CONCLUSION: The results support the concept of cavernous endothelial regeneration by use of SVF as a curative therapy for diabetic ED.

Increased cavernous expression of transforming growth factor-ß1 and activation of the Smad signaling pathway affects erectile dysfunction in men with spinal cord injury.

INTRODUCTION: Transforming growth factor-ß1 (TGF-ß1) is implicated in bladder fibrosis after spinal cord injury (SCI) and in the fibrosis in the corpus cavernosum tissue after cavernous nerve injury. AIM: We investigated the differential expression of TGF-ß1 and the Smad transcription factor, the key molecule for the initiation of TGF-ß-mediated fibrosis, in cavernous tissue from SCI patients. METHODS: After obtaining informed consent and approval from the patients and our institutional review board, we enrolled 5 patients with psychogenic erectile dysfunction (ED) (mean age 36.8 years; range 20-50 years) and 10 patients with neurogenic ED from SCI (mean age 38.8 years; range 18-50 years). Cavernous tissues were obtained by percutaneous biopsy and stained with Masson trichrome, terminal deoxynucleotidyl transferase-mediated deoxyuridine triphosphate nick end labeling (TUNEL), or antibodies to TGF-ß1 and phospho-Smad2. MAIN OUTCOME MEASURES: Semi-quantitative analysis of TGF-ß1 and phospho-Smad2 was performed, and the numbers of apoptotic cells were counted. We also quantified the cavernous collagen area with the use of an image analyzer system. RESULTS: The expression of TGF-ß1 and phospho-Smad2 protein was significantly higher in the SCI group than in the psychogenic group. The TUNEL assay revealed a higher apoptotic index in the SCI group than in the psychogenic group. Higher TGF-ß1 and phospho-Smad2 expression and more apoptotic cells were noted mainly in endothelial cells, smooth muscle cells, and fibroblasts of the SCI group. Double labeling of cavernous tissue with TUNEL and antibody to phospho-Smad2 revealed that most TUNEL-positive cells showed immunoreactivity to phospho-Smad2 staining. Cavernous collagen content was significantly greater in the SCI group than in the psychogenic group. CONCLUSION: Upregulation of TGF-ß1 and activation of the Smad signaling pathway may play important roles in SCI-induced cavernous fibrosis and deterioration of erectile function, which warrants early pharmacological intervention to protect erectile tissue from irreversible damage.

Transcriptional profiling of mouse cavernous pericytes under high-glucose conditions: Implications for diabetic angiopathy.

PURPOSE: Penile erection requires integrative interactions between vascular endothelial cells, pericytes, smooth muscle cells, and autonomic nerves. Furthermore, the importance of the role played by pericytes in the pathogenesis of angiopathy has only recently been appreciated. However, global gene expression in pericytes in diabetes mellitus-induced erectile dysfunction (DMED) remains unclear. We aimed to identify potential target genes related to DMED in mouse cavernous pericytes (MCPs). MATERIALS AND METHODS: Mouse cavernous tissue was allowed to settle under gravity in collagen I-coated dishes, and sprouted cells were subcultivated for experiments. To imitate diabetic conditions, MCPs were treated with normal-glucose (NG, 5 mM) or high-glucose (HG, 30 mM) media for 3 days. Microarray technology was used to evaluate gene expression profiles, and RT-PCR was used to validate sequencing data. Histological examinations and Western blot were used to validate final selected target genes related to DMED. RESULTS: Decreased tube formation and increased apoptosis were detected in MCPs exposed to the HG condition. As shown by microarray analysis, the gene expression profiles of MCPs exposed to the NG or HG condition differed. A total of 2,523 genes with significantly altered expression were classified into 15 major gene categories. After further screening based on gene expression and RT-PCR and histologic results, we found that Hebp1 gene expression was significantly diminished under the HG condition and in DM mice. CONCLUSIONS: This gene profiling study provides new potential targets responsible for diabetes in MCPs. Validation studies suggest that Hebp1 may be a suitable biomarker for DMED.

A mouse model of cavernous nerve injury-induced erectile dysfunction: functional and morphological characterization of the corpus cavernosum.

INTRODUCTION: With the advent of genetically engineered mice, it seems important to develop a mouse model of cavernous nerve injury (CNI). AIM: To establish a mouse model of CNI induced either by nerve crushing or by neurectomy and to evaluate time-dependent derangements in penile hemodynamics in vivo and subsequent histologic alterations in the cavernous tissue. METHODS: Twelve-week-old C57BL/6J mice were divided into 4 groups (N=36 per group): control, sham operation, bilateral cavernous nerve crush, and bilateral cavernous neurectomy group. MAIN OUTCOME MEASURES: Three days and 1, 2, 4, 8, and 12 weeks after CNI, erectile function was measured by electrical stimulation of the cavernous nerve. The penis was then harvested and TUNEL was performed. Immunohistochemical analysis was performed assaying for caspase-3, transforming growth factor-ß1 (TGF-ß1), phospho-Smad2, PECAM-1, factor VIII, and smooth muscle α-actin. The numbers of apoptotic cells and phospho-Smad2-immunopositive cells in endothelial cells or smooth muscle cells were counted. RESULTS: Erectile function was significantly less in the cavernous nerve crushing and neurectomy groups than in the control or sham group. This difference was observed at the earliest time point assayed (day 3) and persisted up to 4 weeks after nerve crushing and to 12 weeks after neurectomy. The apoptotic index peaked at 1 or 2 weeks after CNI and decreased thereafter. Cavernous TGF-ß1 and phospho-Smad expression was also increased after CNI. The numbers of apoptotic cells and phospho-Smad2-immunopositive cells in cavernous endothelial cells and smooth muscle cells were significantly greater in the cavernous nerve crush and cavernous neurectomy groups than in the control or sham group. Conclusion. The mouse is a useful model for studying pathophysiologic mechanisms involved in erectile dysfunction after CNI. Early intervention to prevent apoptosis in smooth muscle cells and endothelial cells or to inhibit cavernous tissue fibrosis is required to restore erectile function.

Transforming growth factor (TGF)-ß type I receptor kinase (ALK5) inhibitor alleviates profibrotic TGF-ß1 responses in fibroblasts derived from Peyronie's plaque.

INTRODUCTION: Transforming growth factor-ß1 (TGF-ß1) has been identified as an important fibrogenic cytokine associated with Peyronie's disease (PD). AIM: The aim of this study was to study the differential expression of the TGF-ß1 and Smad transcription factors in plaque tissue from PD patients and to determine the antifibrotic effect of SKI2162 (SK Chemicals, Seoul, South Korea), a novel small-molecule inhibitor of activin receptor-like kinase 5 (ALK5), a type I receptor of TGF-ß, in primary fibroblasts derived from human PD plaque. METHODS: Plaque tissue was isolated from five PD patients, and tunica albuginea tissue was obtained from four control patients. Plaque tissues from a patient with PD were used for primary fibroblast culture. Fibroblasts were pretreated with SKI2162 (10 µM) and then stimulated with TGF-ß1 (10ng/mL). MAIN OUTCOME MEASURES: The plaque or tunica albuginea tissue was stained with Masson's trichrome or antibody to TGF-ß1, phospho-Smad2 (P-Smad2), and P-Smad3. Protein was extracted from treated fibroblasts for Western blotting, and the membranes were probed with antibody to P-Smad2/Smad2, P-Smad3/Smad3, plasminogen activator inhibitor-1, fibronectin, collagen I, and collagen IV. We also determined the inhibitory effect of SKI2162 on TGF-ß1-induced nuclear translocation of Smad2/3 in fibroblasts. RESULTS: The plaque tissue from PD patients showed higher TGF-ß1, P-Smad2, and P-Smad3 immunoreactivity than did the tunica albuginea tissue from control patients. SKI2162 not only blocked TGF-ß1-induced phosphorylation and nuclear translocation of Smad2 and Smad3, but also inhibited the production of extracellular matrix markers in fibroblasts derived from human PD plaque. CONCLUSION: In light of the pivotal role of TGF-ß and Smads in the pathogenesis of PD, pharmacologic inhibition of ALK5 may represent a novel targeted approach to treating PD.

Intracavernous delivery of synthetic angiopoietin-1 protein as a novel therapeutic strategy for erectile dysfunction in the type II diabetic db/db mouse.

INTRODUCTION: Patients with erectile dysfunction (ED) associated with type II diabetes often have impaired endothelial function and tend to respond poorly to oral phosphodiesterase type 5 inhibitors. Therefore, neovascularization is a promising strategy for curing diabetic ED. AIM: To determine the effectiveness of a soluble, stable, and potent angiopoietin-1 (Ang1) variant, cartilage oligomeric matrix protein (COMP)-Ang1, in promoting cavernous angiogenesis and erectile function in a mouse model of type II diabetic ED. Methods. Sixteen-week-old male db/db mice (in which obesity and type II diabetes are caused by a mutation in the leptin receptor) and control C57BL/6J mice were used and divided into four groups (N=14 per group): age-matched controls; db/db mice receiving two successive intracavernous injections of phosphate-buffered saline (PBS) (days -3 and 0; 20 µL); db/db mice receiving a single intracavernous injection of COMP-Ang1 protein (day 0; 5.8 µg/20 µL); and db/db mice receiving two successive intracavernous injections of COMP-Ang1 protein (days -3 and 0; 5.8 µg/20 µL). MAIN OUTCOME MEASURES: Two weeks later, erectile function was measured by electrical stimulation of the cavernous nerve. The penis was then harvested and stained with antibodies to platelet/endothelial cell adhesion molecule-1 (PECAM-1) (endothelial cell marker), phosphohistone H3 (PH3, a nuclear protein indicative of cell proliferation), phospho-endothelial nitric oxide synthase (eNOS), and eNOS. Penis specimens from a separate group of animals were used for cyclic guanosine monophosphate (cGMP) and cyclic adenosine monophosphate (cAMP) quantification. RESULTS: Local delivery of COMP-Ang1 protein significantly increased eNOS phosphorylation and cGMP and cAMP expression compared with that in the group treated with PBS. Repeated intracavernous injections of COMP-Ang1 protein completely restored erectile function and cavernous endothelial content through enhanced cavernous neoangiogenesis as evaluated by PECAM-1 and PH3 immunohistochemistry and terminal deoxynucleotidyl transferase-mediated deoxyuridine triphosphate nick end labeling assay, whereas a single injection of COMP-Ang1 protein elicited partial improvement. CONCLUSION: Cavernous neovascularization using recombinant Ang1 protein is a novel therapeutic strategy for the treatment of ED resulting from type II diabetes.

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

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

Derangements in endothelial cell-to-cell junctions involved in the pathogenesis of hypercholesterolemia-induced erectile dysfunction.

INTRODUCTION: Endothelial cell-to-cell junctions are crucial for vascular formation, networking, and remodeling of blood vessels as well as for inducing and integrating intracellular signals. AIM: We investigated the differential expression and distribution of endothelial cell-to-cell junction proteins in the penis of mice with hypercholesterolemia-induced erectile dysfunction. METHODS: Two-month-old C57BL/6J mice were fed a diet containing 4% cholesterol and 1% cholic acid, and age-matched control animals were fed a normal diet, for 3 months. We performed dual priming oligonucleotide (DPO)-based multiplex polymerase chain reaction (PCR) (Seegene, Seoul, Korea) to screen the differential gene expression of 21 endothelial cell-to-cell junctions. MAIN OUTCOME MEASURES: At 5 months, erectile function was measured by electrical stimulation of the cavernous nerve, and the penis was harvested and stained with antibody to claudin-5, vascular endothelial (VE)-cadherin, and platelet/endothelial cell adhesion molecule (PECAM)-1 (N = 8 per group). Cavernous specimens from a separate group of animals were used for claudin-5, VE-cadherin, and PECAM-1 reverse transcriptase-PCR and Western blot analysis. RESULTS: Erectile function was significantly lower in hypercholesterolemic mice than in controls. DPO-based multiplex PCR revealed a profound decrease in the gene expression of endothelium-specific cell-to-cell junction proteins, including claudin-5, VE-cadherin, and PECAM-1, in hypercholesterolemic mice compared with that in controls. The expression of claudin-5, VE-cadherin, and PECAM-1 protein evaluated by Western blot or immunohistochemistry was significantly lower in hypercholesterolemic mice than in controls. These endothelial cell-to-cell junction proteins were more sparsely distributed in the endothelium of cavernous sinusoids than in the endothelium of cavernous artery and dorsal blood vessels. CONCLUSION: Down-regulation of the endothelial cell-to-cell junctions and decreased endothelial content in the corpus cavernosum might play a major role in the deterioration of erectile function in hypercholesterolemic mice.

Functional and morphologic characterizations of the diabetic mouse corpus cavernosum: comparison of a multiple low-dose and a single high-dose streptozotocin protocols.

INTRODUCTION: With the advent of genetically modified mice, it seems particularly advantageous to develop a mouse model of diabetic erectile dysfunction. AIM: To establish a mouse model of type I diabetes by implementation of either multiple low-dose streptozotocin (STZ) protocol or single high-dose STZ protocol and to evaluate morphologic alterations in the cavernous tissue and subsequent derangements in penile hemodynamics in vivo. METHODS: Eight-week-old C57BL/6J mice were divided into three groups: a control group, a group administered the multiple low-dose STZ protocol (50 mg/kg x 5 days), and a group administered the single high-dose STZ protocol (200 mg/kg). MAIN OUTCOME MEASURES: After 8 weeks, erectile function was measured by electrical stimulation of the cavernous nerve. The penis was then harvested and stained with hydroethidine (in situ analysis of superoxide anion), TUNEL, or antibodies to nitrotyrosine (marker of peroxynitrite formation), PECAM-1, smooth muscle alpha-actin, and phospho-eNOS. Penis specimens from a separate group of animals were used for phospho-eNOS and eNOS western blot or cGMP determination. RESULTS: Erectile function was significantly less in diabetic groups than in control group. The generation of superoxide anion and nitrotyrosine and the number of apoptotic cells in both cavernous endothelial and smooth muscle cells were significantly higher in diabetic groups than in control group. Cavernous tissue phospho-eNOS and cGMP expression and the number of endothelial and smooth muscle cells were lower in diabetic groups than in control group. Both diabetic models resulted in similar structural and functional derangements in the corpus cavernosum; however, the mortality rate was higher in mice receiving single high-dose of STZ than in those receiving multiple low-doses. CONCLUSION: The mouse model of type I diabetes is useful and technically feasible for the study of the pathophysiologic mechanisms involved in diabetic erectile dysfunction.

IN-1130, a novel transforming growth factor-beta type I receptor kinase (activin receptor-like kinase 5) inhibitor, promotes regression of fibrotic plaque and corrects penile curvature in a rat model of Peyronie's disease.

INTRODUCTION: Transforming growth factor-beta1 (TGF-beta1) has been known to play a crucial role in the pathogenesis of Peyronie's disease (PD). AIM: The aim of this paper was to investigate the therapeutic effect of IN-1130, a novel small molecule inhibitor of activin receptor-like kinase (ALK)5, a type I receptor of TGF-beta, in an animal model of PD. METHODS: PD was induced in rats through repeated injections of adenovirus expressing TGF-beta1 (days 0, 3, and 6; 1 x 10(10) particles/0.1 mL, respectively) into the tunica albuginea. The rats were divided into five groups (N = 10 per group): group 1, age-matched controls without treatment; group 2, age-matched controls receiving repeated injections of IN-1130 (days 30 and 37; 5 mg/kg in 0.1 mL saline, respectively); group 3, PD rats without treatment; group 4, PD rats receiving repeated injections of saline (days 30 and 37; 0.1 mL, respectively); group 5, PD rats receiving repeated injections of IN-1130 (days 30 and 37; 5 mg/kg in 0.1 mL saline, respectively) into the lesion. MAIN OUTCOME MEASURES: Penile curvature was evaluated by use of an artificial erection test at day 45, and the penis was then harvested for histologic examination. Collagen in the plaque was quantitatively assessed by hydroxyproline determination. RESULTS: IN-1130 induced significant regression of fibrotic plaque through reduced infiltration of inflammatory cells, reduced transnuclear expression of phospho-Smad2/phospho-Smad3, reduced hydroxyproline content, and reduced cartilage content and restoration of elastin fibers in the fibrotic plaque of PD rats, which was accompanied by the correction of penile curvature. CONCLUSION: Antagonizing TGF-beta signaling through the use of ALK5 inhibitors may represent an exciting new therapeutic strategy for the future treatment of PD.

Role of increased penile expression of transforming growth factor-beta1 and activation of the Smad signaling pathway in erectile dysfunction in streptozotocin-induced diabetic rats.

INTRODUCTION: It has been suggested that transforming growth factor-beta1 (TGF-beta1) plays an important role in the pathogenesis of diabetes-induced erectile dysfunction. AIM: To investigate the expression and activity of Smad transcriptional factors, the key molecules for the initiation of TGF-beta-mediated fibrosis, in the penis of streptozotocin (STZ)-induced diabetic rats. METHODS: Fifty-two 8-week-old Sprague-Dawley rats were used and divided into control and diabetic groups. Diabetes was induced by an intravenous injection of STZ. MAIN OUTCOME MEASURES: Eight weeks later, erectile function was measured by electrical stimulation of the cavernous nerve (N = 12 per group). The penis was harvested and stained with Masson trichrome or antibody to TGF-beta1, phospho-Smad2 (P-Smad2), smooth muscle alpha-actin, and factor VIII (N = 12 per group). Penis specimens from a separate group of animals were used for TGF-beta1 enzyme-linked immunosorbent assay (ELISA), P-Smad2/Smad2, phospho-Smad3 (P-Smad3)/Smad3, fibronectin, collagen I, and collagen IV western blot, or hydroxyproline determination. RESULTS: Erectile function was significantly reduced in diabetic rats compared with that in controls. The expression of TGF-beta1, P-Smad2, and P-Smad3 protein evaluated by ELISA or western blot was higher in diabetic rats than in controls. Compared with that in control rats, P-Smad2 expression was higher mainly in smooth muscle cells and fibroblasts of diabetic rats, whereas no significant differences were noted in endothelial cells or in the dorsal nerve bundle. Cavernous smooth muscle and endothelial cell contents were lower in diabetic rats than in controls. Cavernous fibronectin, collagen IV, and hydroxyproline content was significantly higher in diabetic rats than in controls. CONCLUSION: Upregulation of TGF-beta1 and activation of the Smad signaling pathway in the penis of diabetic rats might play important roles in diabetes-induced structural changes and deterioration of erectile function.