SHH regulates penile morphology and smooth muscle through a mechanism involving BMP4 and GREM1.

BACKGROUND: The cavernous nerve (CN) is frequently damaged in prostatectomy and diabetic patients with erectile dysfunction (ED), initiating changes in penile morphology including an acute and intense phase of apoptosis in penile smooth muscle and increased collagen, which alter penile architecture and make corpora cavernosa smooth muscle less able to relax in response to neurotransmitters, resulting in ED. AIM: Sonic hedgehog (SHH) is a critical regulator of penile smooth muscle, and SHH treatment suppresses penile remodeling after CN injury through an unknown mechanism; we examine if part of the mechanism of how SHH preserves smooth muscle after CN injury involves bone morphogenetic protein 4 (BMP4) and gremlin1 (GREM1). METHODS: Primary cultures of smooth muscle cells were established from prostatectomy, diabetic, hypertension and Peyronie's (control) (N = 18) patients. Cultures were characterized by ACTA2, CD31, P4HB, and nNOS immunohistochemical analysis. Patient smooth muscle cell growth was quantified in response to BMP4 and GREM1 treatment. Adult Sprague Dawley rats underwent 1 of 3 surgeries: (1) uninjured or CN-injured rats were treated with BMP4, GREM1, or mouse serum albumin (control) proteins via Affi-Gel beads (N = 16) or peptide amphiphile (PA) (N = 26) for 3 and 14 days, and trichrome stain was performed; (2) rats underwent sham (N = 3), CN injury (N = 9), or CN injury and SHH PA treatment for 1, 2, and 4 days (N = 9). OUTCOMES: Western analysis for BMP4 and GREM1 was performed; (3) rats were treated with 5E1 SHH inhibitor (N = 6) or IgG (control; N = 6) for 2 and 4 days, and BMP4 and GREM1 localization was examined. Statistics were performed by analysis of variance with Scheffé's post hoc test. RESULTS: BMP4 increased patient smooth muscle cell growth, and GREM1 decreased growth. In rats, BMP4 treatment via Affi-Gel beads and PA increased smooth muscle at 3 and 14 days of treatment. GREM1 treatment caused increased collagen and smooth muscle at 3 days, which switched to primarily collagen at 14 days. CN injury increased BMP4 and GREM1, while SHH PA altered Western band size, suggesting alternative cleavage and range of BMP4 and GREM1 signaling. SHH inhibition in rats increased BMP4 and GREM1 in fibroblasts. CLINICAL IMPLICATIONS: Understanding how SHH PA preserves and regenerates penile morphology after CN injury will aid development of ED therapies. STRENGTHS AND LIMITATIONS: SHH treatment alters BMP4 and GREM1 localization and range of signaling, which can affect penile morphology. CONCLUSION: Part of the mechanism of how SHH regulates corpora cavernosa smooth muscle involves BMP4 and GREM1.

BMP4 and GREM1 are targets of SHH signaling and downstream regulators of collagen in the penis.

BACKGROUND: Cavernous nerve (CN) injury, caused by prostatectomy and diabetes, initiates a remodeling process (smooth muscle apoptosis and increased collagen) in the corpora cavernosa of the penis of patients and animal models that is an underlying cause of erectile dysfunction (ED), and the Sonic hedgehog (SHH) pathway plays an essential role in the response of the penis to denervation, as collagen increases with SHH inhibition and decreases with SHH treatment. AIM: We examined if part of the mechanism of how SHH prevents penile remodeling and increased collagen with CN injury involves bone morphogenetic protein 4 (BMP4) and gremlin1 (GREM1) and examined the relationship between SHH, BMP4, GREM1, and collagen in penis of ED patients and rat models of CN injury, SHH inhibition, and SHH, BMP4, and GREM1 treatment. METHODS: Corpora cavernosa of Peyronie's disease (control), prostatectomy, and diabetic ED patients were obtained (N = 30). Adult Sprague Dawley rats (n = 90) underwent (1) CN crush (1-7 days) or sham surgery; (2) CN injury and BMP4, GREM1, or mouse serum albumin (control) treatment via Affi-Gel beads or peptide amphiphile (PA) for 14 days; (3) 5E1 SHH inhibitor, IgG, or phosphate-buffered saline (control) treatment for 2 to 4 days; or (4) CN crush with mouse serum albumin or SHH for 9 days. OUTCOMES: Immunohistochemical and Western analysis for BMP4 and GREM1, and collagen analysis by hydroxyproline and trichrome stain were performed. RESULTS: BMP4 and GREM1 proteins were identified in corpora cavernosa smooth muscle of prostatectomy, diabetic, and Peyronie's patients, and in rat smooth muscle, sympathetic nerve fibers, perineurium, blood vessels, and urethra. Collagen decreased 25.4% in rats with CN injury and BMP4 treatment (P = .02) and increased 61.3% with CN injury and GREM1 treatment (P = .005). Trichrome stain showed increased collagen in rats treated with GREM1. Western analysis identified increased BMP4 and GREM1 in corpora cavernosa of prostatectomy and diabetic patients, and after CN injury (1-2 days) in our rat model. Localization of BMP4 and GREM1 changed with SHH inhibition. SHH treatment increased the monomer form of BMP4 and GREM1, altering their range of signaling. CLINICAL IMPLICATIONS: A better understanding of penile remodeling and how fibrosis occurs with loss of innervation is essential for development of novel ED therapies. STRENGTHS AND LIMITATIONS: The relationship between SHH, BMP4, GREM1, and collagen is complex in the penis. CONCLUSION: BMP4 and GREM1 are downstream targets of SHH that impact collagen and may be useful in collaboration with SHH to prevent penile remodeling and ED.

Princeton IV consensus guidelines: PDE5 inhibitors and cardiac health.

BACKGROUND: In 1999, 1 year after the approval of the first oral phosphodiesterase type 5 (PDE5) inhibitor for the treatment of erectile dysfunction (ED), the first Princeton Consensus Conference was held to address the clinical management of men with ED who also had cardiovascular disease. These issues were readdressed in the second and third conferences. In the 13 years since the last Princeton Consensus Conference, the experience with PDE5 inhibitors is more robust, and recent new data have emerged regarding not only safety and drug-drug interactions, but also a potential cardioprotective effect of these drugs. AIM: In March 2023, an interdisciplinary group of scientists and practitioners met for the fourth Princeton Consensus Guidelines at the Huntington Medical Research Institutes in Pasadena, California, to readdress the cardiovascular workup of men presenting with ED as well as the approach to treatment of ED in men with known cardiovascular disease. METHOD: A series of lectures from experts in the field followed by Delphi-type discussions were developed to reach consensus. OUTCOMES: Consensus was reached regarding a number of issues related to erectile dysfunction and the interaction with cardiovascular health and phosphodiesterase-5 inhibitors. RESULTS: An algorithm based on recent recommendations of the American College of Cardiology and American Heart Association, including the use of computed tomography coronary artery calcium scoring, was integrated into the evaluation of men presenting with ED. Additionally, the issue of nitrate use was further considered in an algorithm regarding the treatment of ED patients with coronary artery disease. Other topics included the psychological effect of ED and the benefits of treating it; the mechanism of action of the PDE5 inhibitors; drug-drug interactions; optimizing use of a PDE5 inhibitors; rare adverse events; potential cardiovascular benefits observed in recent retrospective studies; adulteration of dietary supplements with PDE5 inhibitors; the pros and cons of over-the-counter PDE5 inhibitors; non-PDE5 inhibitor therapy for ED including restorative therapies such as stem cells, platelet-rich plasma, and shock therapy; other non-PDE5 inhibitor therapies, including injection therapy and penile prostheses; the issue of safety and effectiveness of PDE5 inhibitors in women; and recommendations for future studies in the field of sexual dysfunction and PDE5 inhibitor use were discussed. CLINICAL IMPLICATIONS: Algorithms and tables were developed to help guide the clinician in dealing with the interaction of ED and cardiovascular risk and disease. STRENGTHS AND LIMITATIONS: Strengths include the expertise of the participants and consensus recommendations. Limitations included that participants were from the United States only for this particular meeting. CONCLUSION: The issue of the intersection between cardiovascular health and sexual health remains an important topic with new studies suggesting the cardiovascular safety of PDE5 inhibitors.

Pathway analysis of microarray data from corpora cavernosal tissue of patients with a prostatectomy or Peyronie disease in comparison with a cavernous nerve-injured rat model of erectile dysfunction.

INTRODUCTION: Patients with a prostatectomy are at high risk of developing erectile dysfunction (ED) that is refractory to phosphodiesterase type 5 inhibitors. The cavernous nerve (CN) is frequently damaged during prostatectomy, causing loss of innervation to the penis. This initiates corpora cavernosal remodeling (apoptosis and fibrosis) and results in ED. AIM: To aid in the development of novel ED therapies, the current aim was to obtain a global understanding of how signaling mechanisms alter in the corpora cavernosa with loss of CN innervation that results in ED. METHODS: Microarray and pathway analysis were performed on the corpora cavernosal tissue of patients with a prostatectomy (n = 3) or Peyronie disease (control, n = 3). Results were compared with an analysis of a Sprague-Dawley rat CN injury model (n = 10). RNA was extracted by TRIzol, DNase treated, and purified by a Qiagen Mini Kit. Microarray was performed with the Human Gene 2.0 ST Array and the RU34 rat array. Differentially expressed genes were identified through several analytic tools (ShinyGO, Ingenuity, WebGestalt) and databases (GO, Reactome). A 2-fold change was used as the threshold for differential expression. OUTCOMES: Pathways that were altered (up- or downregulated) in response to CN injury in the prostatectomy patients and a rat CN injury model were determined. RESULTS: Microarray identified 197 differentially expressed protein-coding genes in the corpora cavernosa from the prostatectomy cohort, with 100 genes upregulated and 97 genes downregulated. Altered signaling pathways that were identified that affect tissue morphology included the following: neurologic disease, cell death and survival, tissue and cellular development, skeletal and muscle development and disorders, connective tissue development and function, tissue morphology, embryonic development, growth and proliferation, cell-to-cell signaling, and cell function and maintenance. These human pathways have high similarity to those observed in the CN-injured rat ED model. CLINICAL IMPLICATIONS: Significant penile remodeling continues in patients long after the acute surgical injury to the CN takes place, offering the opportunity for clinical intervention to reverse penile remodeling and improve erectile function. STRENGTHS AND LIMITATIONS: Understanding how signaling pathways change in response to CN injury and how these changes translate to altered morphology of the corpora cavernosa and ensuing ED is critical to identify strategic targets for therapy development. CONCLUSION: Altered signaling in pathways that regulate tissue homeostasis, morphogenesis, and development was identified in penes of patients with a prostatectomy, and competitive forces of apoptosis and proliferation/regeneration were found to compete to establish dominance after CN injury. How these pathways interact to regulate penis tissue homeostasis is a complex process that requires further investigation.

Pathway Enrichment Analysis of Microarray Data Fom Human Penis of Diabetic and Peyronie's Patients, in Comparison With Diabetic Rat Erectile Dysfunction Models.

BACKGROUND: Erectile dysfunction (ED) is a debilitating medical condition in which current treatments are minimally effective in diabetic patients due to neuropathy of the cavernous nerve, a peripheral nerve that innervates the penis. Loss of innervation causes apoptosis of penile smooth muscle, remodeling of corpora cavernosa (penile erectile tissue) morphology, and ED. AIM: In this study, microarray and pathway analysis were used to obtain a global understanding of how signaling mechanisms are altered in diabetic patients and animal models as ED develops, in order to identify novel targets for disease management, and points of intervention for clinical therapy development. METHODS AND OUTCOMES: Human corpora cavernosal tissue was obtained from diabetic (n = 4) and Peyronie's (control, n = 3) patients that were undergoing prosthesis implant to treat ED, and BB/WOR diabetic (n = 5) and resistant (n = 5) rats. RNA was extracted using TRIzol, DNase treated, and purified by Qiagen mini kit. Microarray was performed using the Human Gene 2.0 ST Array. (i) Alterations in patient and diabetic rat pathway signaling were examined using several analytical tools (ShinyGO, Metascape, WebGestalt, STRING) and databases, (ii) Strengths/weaknesses of the different pathway analysis tools were compared, and (iii) Comparison of human and rat (BB/WOR and Streptozotocin) pathway analysis was performed. Two technical replicates were performed. P value (FDR) < .15 was used as threshold for differential expression. FDR < 0.05 was considered significant. RESULTS: Microarray identified 182 differentially expressed protein-coding genes. Pathway analysis revealed similar enrichments with different analytical tools. Down regulated pathways include development, tubular structure, sprouting, cell death, ischemia, angiogenesis, transcription, second messengers, and stem cell differentiation. ED patients, who have diabetes, incur significant loss of normal regulatory processes required for repair and replacement of injured corpora cavernosal tissue. Combined with loss of apoptotic regulatory mechanisms, this results in significant architectural remodeling of the corpora cavernosa, and loss of regenerative capacity in the penis. CLINICAL TRANSLATION: This first report of microarray and pathway analysis in human corpora cavernosa, is critical for identification of novel pathways pertinent to ED and for validating animal models. STRENGTHS AND LIMITATIONS: The analysis of tissue specific gene expression profiles provides a means of understanding drivers of disease and identifying novel pathways for clinical intervention. CONCLUSION: Penis from diabetic ED patients lacks capacity for maintenance of corpora cavernosal architecture and regeneration, which are critical points for intervention for therapy development. Searl T, Ohlander S, McVary KT, et al., Pathway Enrichment Analysis of Microarray Data Fom Human Penis of Diabetic and Peyronie's Patients, in Comparison With Diabetic Rat Erectile Dysfunction Models. J Sex Med 2022;19:37-53.

Sonic Hedgehog Signaling in Primary Culture of Human Corpora Cavernosal Tissue From Prostatectomy, Diabetic, and Peyronie's Patients.

BACKGROUND: Cavernous nerve (CN) injury causes penile remodeling, including smooth muscle apoptosis and increased collagen, which results in erectile dysfunction (ED), and prevention of this remodeling is critical for novel ED therapy development. AIM: We developed 2 peptide amphiphile (PA) hydrogel delivery vehicles for Sonic hedgehog (SHH) protein to the penis and CN, which effectively suppress penile distrophic remodeling (apoptosis and fibrosis), in vivo in a rat CN injury model, and the aim of this study is to determine if SHH PA can be used to regenerate human corpora cavernosal smooth muscle deriving from multiple ED origins. METHODS: Corpora cavernosal tissue was obtained from prostatectomy, diabetic, hypertension, cardiovascular disease and Peyronie's (control) patients (n = 21). Primary cultures (n = 21) were established, and corpora cavernosal cells were treated with SHH protein, MSA (control), 5E1 SHH inhibitor, and PBS (control). Growth was quantified by counting the number of cells at 3-4 days. Statistics were performed by ANOVA with Scheffe's post hoc test. Concentration of SHH protein for maximal growth was optimized, and a more active SHH protein examined. OUTCOMES: Cultures were characterized by immunohistochemical analysis with ACTA2, CD31, nNOS and P4HB, and smooth muscle was quantified in comparison to DAPI. RESULTS: Cultures established were >97% smooth muscle. SHH protein increased growth of smooth muscle cells from prostatectomy, diabetic, and Peyronie's patients in a similar manner (49%-51%), and SHH inhibition decreased growth (20%-33%). There was no difference in growth using 25 ug and 10 ug SHH protein, suggesting a threshold concentration of SHH protein above which smooth muscle growth is enhanced. A more active lipid modified SHH peptide further enhanced growth (15%), indicating a more robust growth response. SHH increased growth in smooth muscle cells from hypertension (37%) and cardiovascular disease (32%) patients. SHH protein increased growth under normal and high glucose conditions, suggesting that high glucose conditions that may be present in under controlled diabetic patients would not detract from SHH regenerative capacity. CLINICAL IMPLICATIONS: SHH PA would be beneficial to enhance smooth muscle regeneration in patients with ED of multiple etiologies. STRENGTHS AND LIMITATIONS: Understanding how human corpora cavernosal tissue responds to SHH treatment is critical for clinical translation of SHH PA to ED patients. CONCLUSION: Corpora cavernosal smooth muscle from all ED patients responded to SHH treatment with increased growth. Stupp, SI. Sonic Hedgehog Signaling in Primary Culture of Human Corpora Cavernosal Tissue From Prostatectomy, Diabetic, and Peyronie's Patients. J Sex Med 2022;19:1228-1242.

Development of a North American coordinated registry network for surgical treatment of benign prostatic hyperplasia.

PURPOSE: To create a prospective, multicenter coordinated registry network (CRN) of robust "real world" data for benign prostatic hyperplasia (BPH) that links surgical practices to objective and subjective outcomes of patients who undergo surgery for the improvement in lower urinary tract symptoms (LUTS) secondary to BPH. METHODS: We gathered a group of BPH experts from various institutions to identify the minimum core data elements needed to assess BPH procedures. To achieve consensus on the data elements, we used a Delphi method adaptation, in which a series of surveys were answered by the expert panel individually and anonymously. Survey results were collected and analyzed. Questions for the following round were based on response analysis from the prior survey. This process was repeated until consensus was achieved. RESULTS: Participation rates in the first and second rounds were 100% and 90%, respectively. The expert panel reached consensus on 148 data elements out of the 182 proposed, capturing patient medical and surgical history, procedure, discharge, short- and long-term follow-up, device factors, surgery, and surgeon factors. CONCLUSION: We have successfully developed a set of core data elements to support the study of BPH surgical therapies by gathering an expert panel on BPH and using the Delphi method. These data elements influence provider decisions about treatment and include important outcomes related to efficacy and safety.

Final 5-Year Outcomes of the Multicenter Randomized Sham-Controlled Trial of a Water Vapor Thermal Therapy for Treatment of Moderate to Severe Lower Urinary Tract Symptoms Secondary to Benign Prostatic Hyperplasia.

PURPOSE: We present final 5-year outcomes of the multicenter randomized sham-controlled trial of a water vapor therapy (Rezum™) for treatment of moderate to severe lower urinary tract symptoms due to benign prostatic hyperplasia. MATERIALS AND METHODS: A total of 197 subjects >50 years of age with International Prostate Symptom Score ≥13, maximum flow rate ≤15 ml/second and prostate volume 30 to 80 cc were randomized and followed for 5 years. From the control arm of 61 subjects, a subset of 53 subjects requalified and after 3 months received treatment as part of the crossover group and were also followed for 5 years. The total number of vapor treatments to each lobe of the prostate was determined by length of prostatic urethra and included middle lobe treatment per physician discretion. RESULTS: Significant improvement of lower urinary tract symptoms was observed at <3 months post-thermal therapy, remaining durable through 5 years in the treatment group (International Prostate Symptom Score reduced 48%, quality of life increased 45%, maximum flow rate improved 44%, Benign Prostatic Hyperplasia Impact Index decreased 48%). Surgical re-treatment rate was 4.4% with no reports of device or procedure related sexual dysfunction or sustained de novo erectile dysfunction. Results within the crossover group were similar through 5 years. CONCLUSIONS: Minimally invasive treatment with water vapor thermal therapy provides significant and durable symptom relief as well as flow rate improvements through 5 years, with low surgical re-treatment rates and without impacting sexual function. It is a versatile therapy, providing successful treatment to obstructive lateral and middle lobes.

Management of Lower Urinary Tract Symptoms Attributed to Benign Prostatic Hyperplasia: AUA GUIDELINE PART II-Surgical Evaluation and Treatment.

PURPOSE: Surgical therapies for symptomatic bladder outlet obstruction (BOO) due to benign prostatic hyperplasia (BPH) are many, and vary from minimally invasive office based to high-cost operative approaches. This Guideline presents effective evidence-based surgical management of male lower urinary tract symptoms secondary/attributed to BPH (LUTS/BPH). See accompanying algorithm for a detailed summary of procedures (figure[Figure: see text]). MATERIALS/METHODS: The Minnesota Evidence Review Team searched Ovid MEDLINE, Embase, Cochrane Library, and AHRQ databases to identify eligible studies published between January 2007 and September 2020, which includes the initial publication (2018) and amendments (2019, 2020). The Team also reviewed articles identified by Guideline Panel Members. When sufficient evidence existed, the body of evidence was assigned a strength rating of A (high), B (moderate), or C (low) for support of Strong, Moderate, or Conditional Recommendations. In the absence of sufficient evidence, information is provided as Clinical Principles and Expert Opinions (table[Table: see text]). RESULTS: Twenty-four guideline statements pertinent to pre-operative and surgical management were developed. Appropriate levels of evidence and supporting text were created to direct urologic providers towards suitable and safe operative interventions for individual patient characteristics. A re-treatment section was created to direct attention to longevity and outcomes with individual approaches to help guide patient counselling and therapeutic decisions. CONCLUSION: Pre-operative and surgical management of BPH requires attention to individual patient characteristics and procedural risk. Clinicians should adhere to recommendations and familiarize themselves with criteria that yields the highest likelihood of surgical success when choosing a particular approach for a particular patient.

Management of Lower Urinary Tract Symptoms Attributed to Benign Prostatic Hyperplasia: AUA GUIDELINE PART I-Initial Work-up and Medical Management.

PURPOSE: Benign prostatic hyperplasia (BPH) is a histologic diagnosis describing proliferation of smooth muscle and epithelial cells within the prostatic transition zone. The prevalence and severity of lower urinary tract symptoms (LUTS) in aging men are progressive and impact the health and welfare of society. This revised Guideline provides a useful reference on effective evidence-based management of male LUTS/BPH. See the accompanying algorithm for a summary of the procedures detailed in the Guideline (figures 1 and 2[Figure: see text][Figure: see text]). MATERIALS AND METHODS: The Minnesota Evidence Review Team searched Ovid MEDLINE, Embase, Cochrane Library, and AHRQ databases to identify eligible English language studies published between January 2008 and April 2019, then updated through December 2020. Search terms included Medical Subject Headings (MeSH) and keywords for pharmacological therapies, drug classes, and terms related to LUTS or BPH. When sufficient evidence existed, the body of evidence was assigned a strength rating of A (high), B (moderate), or C (low) for support of Strong, Moderate, or Conditional Recommendations. In the absence of sufficient evidence, information is provided as Clinical Principles and Expert Opinions (table 1[Table: see text]). RESULTS: Nineteen guideline statements pertinent to evaluation, work-up, and medical management were developed. Appropriate levels of evidence and supporting text were created to direct both primary care and urologic providers towards streamlined and suitable practices. CONCLUSIONS: The work up and medical management of BPH requires attention to individual patient characteristics, while also respecting common principles. Clinicians should adhere to recommendations and familiarize themselves with standards of BPH management.

The rising worldwide impact of benign prostatic hyperplasia.

OBJECTIVES: To describe the trend in the impact of lower urinary tract symptoms attributed to benign prostatic hyperplasia (LUTS/BPH) on a global scale using the Global Burden of Disease (GBD) database. MATERIALS AND METHODS: Using the GBD database, worldwide data aggregated from registries and health systems from 1990 to 2017 were filtered for LUTS/BPH diagnoses. Calculation of years lived with disability (YLD) were compared with other urological diseases. YLD were calculated by a standardized method using assigned disability weights. The GBD-defined sociodemographic index (SDI) was used to assess impact of LUTS/BPH by global SDI quintile. RESULTS: Global Burden of Disease data over the 1990-2017 study period were summarized and global numbers and trends noted with other urological diseases for comparison. A total of 2 427 334 YLD were attributed to BPH in 2017 alone, almost three times more than those attributed to the next highest urological disease, prostate cancer (843 227 YLD). When stratified by SDI quintile, a much lower impact of BPH was found in the bottom three quintiles, despite this subset representing 66.9% of the 2017 world population. CONCLUSIONS: Lower urinary tract symptoms attributed to benign prostatic hyperplasia exert a rapidly rising human burden far exceeding other urological diseases. As the population ages and men in a lower SDI enjoy increased life expectancy and decreased competing mortalities, a continually accelerating wave of LUTS/BPH can be forecast. These epidemiological trends have serious implications for the future allocation of resources and the global urological workforce.

Caspase Signaling in ED Patients and Animal Models.

BACKGROUND: Current treatments for erectile dysfunction (ED) are ineffective in prostatectomy and diabetic patients due to cavernous nerve (CN) injury, which causes smooth muscle apoptosis, penile remodeling, and ED. Apoptosis can occur via the intrinsic (caspase 9) or extrinsic (caspase 8) pathway. AIM: We examined the mechanism of how apoptosis occurs in ED patients and CN injury rat models to determine points of intervention for therapy development. METHODS AND OUTCOMES: Immunohistochemical and western analyses for caspase 3-cleaved, caspase-8 and caspase-9 (pro and active forms) were performed in corpora cavernosal tissue from Peyronie's, prostatectomy and diabetic ED patients (n = 33), penis from adult Sprague Dawley rats that underwent CN crush (n = 24), BB/WOR diabetic and control rats (n = 8), and aged rats (n = 9). RESULTS: Caspase 3-cleaved was observed in corpora cavernosa from Peyronie's patients and at higher abundance in prostatectomy and diabetic tissues. Apoptosis takes place primarily through the extrinsic (caspase 8) pathway in penis tissue of ED patients. In the CN crushed rat, caspase 3-cleaved was abundant from 1-9 days after injury, and apoptosis takes place primarily via the intrinsic (caspase 9) pathway. Caspase 9 was first observed and most abundant in a layer under the tunica, and after several days was observed in the lining of and between the sinuses of the corpora cavernosa. Caspase 8 was initially observed at low abundance in the rat corpora cavernosa and was not observed at later time points after CN injury. Aged and diabetic rat penis primarily exhibited intrinsic mechanisms, with diabetic rats also exhibiting mild extrinsic activation. CLINICAL TRANSLATION: Knowing how and when to intervene to prevent the apoptotic response most effectively is critical for the development of drugs to prevent ED, morphological remodeling of the corpora cavernosa, and thus, disease management. STRENGTHS AND LIMITATIONS: Animal models may diverge from the signaling mechanisms observed in ED patients. While the rat utilizes primarily caspase 9, there is a significant flux through caspase 8 early on, making it a reasonable model, as long as the timing of apoptosis is considered after CN injury. CONCLUSIONS: Apoptosis takes place primarily through the extrinsic caspase 8 dependent pathway in ED patients and via the intrinsic caspase 9 dependent pathway in commonly used CN crush ED models. This is an important consideration for study design and interpretation that must be taken into account for therapy development and testing of drugs, and our therapeutic targets should ideally inhibit both apoptotic mechanisms. Martin S, Harrington DA, Ohlander S, et al. Caspase Signaling in ED Patients and Animal Models. J Sex Med 2021;18:711-722.

Peptide amphiphile nanofiber hydrogel delivery of Sonic hedgehog protein to the penis and cavernous nerve suppresses intrinsic and extrinsic apoptotic signaling mechanisms, which are an underlying cause of erectile dysfunction.

Erectile dysfunction (ED) is a common and debilitating condition with high impact on quality of life. An underlying cause of ED is apoptosis of penile smooth muscle, which occurs with cavernous nerve injury, in prostatectomy, diabetic and aging patients. We are developing peptide amphiphile (PA) nanofiber hydrogels as an in vivo delivery vehicle for Sonic hedgehog protein to the penis and cavernous nerve to prevent the apoptotic response. We examine two important aspects required for clinical application of the biomaterials: if SHH PA suppresses intrinsic (caspase 9) and extrinsic (caspase 8) apoptotic mechanisms, and if suppressing one apoptotic mechanism forces apoptosis to occur via a different mechanism. We show that SHH PA suppresses both caspase 9 and 8 apoptotic mechanisms, and suppressing caspase 9 did not shift signaling to caspase 8. SHH PA has significant clinical potential as a preventative ED therapy, by management of intrinsic and extrinsic apoptotic mechanisms.

Surgical Reintervention Rate after Prostatic Urethral Lift: Systematic Review and Meta-Analysis Involving over 2,000 Patients.

PURPOSE: The surgical reintervention rate after prostatic urethral lift is not well characterized but has been estimated at 2% to 3% per year. We performed a systematic review and meta-analysis to determine the surgical reintervention rate after prostatic urethral lift. MATERIALS AND METHODS: We systematically searched MEDLINE®, Embase® and the Cochrane Central Register of Controlled Trials for studies of men treated with prostatic urethral lift reporting at least 1 year of maximum followup data. We performed a random effects meta-analysis to estimate the annual rate of surgical reintervention after prostatic urethral lift, including those performed for lower urinary tract symptoms or involving device explant, additions or replacement. The robustness of the meta-analysis conclusions was evaluated in a one-study removed analysis and heterogeneity was investigated with a subgroup analysis. RESULTS: In 11 studies (2,016 patients) 153 surgical reinterventions were performed, among which transurethral resection of the prostate/laser (51.0%), repeat prostatic urethral lift (32.7%) and device explant (19.6%) were most common. The annual rate of surgical reintervention was 6.0% per year (95% CI 3.0-8.9). These results were not significantly influenced by any single study. The annual rate of surgical intervention was significantly influenced by the mean duration of patient followup. Surgical reintervention rates were 4.3% per year in studies with 1 year or less mean followup, 10.7% per year in studies with more than 1 year to 3 years mean followup and 5.8% per year in a single study with more than 3 years mean followup (p=0.04). CONCLUSIONS: The surgical reintervention rate with prostatic urethral lift is 6.0% per year and is higher in studies with longer followup durations.

Trends in Lower Urinary Tract Symptoms Associated with Benign Prostatic Hyperplasia, 2004 to 2013: the Urologic Diseases in America Project.

PURPOSE: Our current understanding of recent trends in the management of lower urinary tract symptoms associated with benign prostatic hyperplasia is incomplete, particularly in younger men. The 2018 Urologic Diseases in America Project attempted to fill this gap by analyzing multiple large administrative claims databases which include men of all ages and permit longitudinal followup. To our knowledge we report these findings for the first time in the scientific literature. MATERIALS AND METHODS: The 2 data sources used in this study included the de-identified Optum® Clinformatics® Data Mart database for men 40 to 64 years old and the Medicare 5% Sample for men 65 years old or older. To assess trends in lower urinary tract symptoms/benign prostatic hyperplasia related medication prescriptions and surgical procedures from 2004 to 2013 we created annual cross-sectional cohorts and a longitudinal cohort of patients with incident lower urinary tract symptoms/benign prostatic hyperplasia and 5 years of followup. RESULTS: The use of medications related to lower urinary tract symptoms/benign prostatic hyperplasia increased with age, particularly among men 40 to 60 years old. While medication use increased with time, surgical procedures decreased. Increasing age correlated with a higher rate of surgical procedures in the longitudinal cohort. Younger men were more likely to elect treatments of lower urinary tract symptoms/benign prostatic hyperplasia which reportedly optimize sexual function. CONCLUSIONS: Medication use increased and surgery decreased during the study period. Treatment approaches to lower urinary tract symptoms/benign prostatic hyperplasia varied greatly by patient age. While the minority of men in the fifth and sixth decades of life required treatment, a sharp increase in treatment use was seen between these decades. Younger men were more likely to elect less invasive surgical options. Future studies of lower urinary tract symptoms/benign prostatic hyperplasia should focus on age specific treatment selection.

Disparities in Benign Prostatic Hyperplasia Progression: Predictors of Presentation to the Emergency Department in Urinary Retention.

PURPOSE: This retrospective cohort study evaluates the characteristics of patients who presented to the emergency department with acute urinary retention. MATERIALS AND METHODS: Using the Healthcare Cost and Utilization Project State Emergency Department Databases we conducted a retrospective cohort study of patients who presented to emergency departments in Florida between 2005 and 2015. Male patients age 45 years or older who presented with diagnosis codes for acute urinary retention and lower urinary tract symptoms/benign prostatic hyperplasia were considered. Information was collected on age, race/ethnicity, primary insurance and rural-urban commuting area codes. RESULTS: The mean age for males presenting with acute urinary retention was 72.2 years, which was 10.6 years older than those presenting for nonurological complaints (p <0.001). Multivariable analysis adjusted for measured confounders found all covariates to be significant. The risk of presenting to the emergency department for acute urinary retention from lower urinary tract symptoms/benign prostatic hyperplasia increased with age, with the 75 to less than 85-year-old age group at the highest risk (OR 15.96, p <0.001). Other factors associated acute urinary retention included African American (OR 1.15, p <0.001) or Hispanic (OR 1.75, p <0.001) race, Medicare (OR 1.27, p <0.001) or private (OR 1.33, p <0.001) insurance, and urban rural-urban commuting area codes (OR 1.31, p <0.001). CONCLUSIONS: Male patients who presented to the emergency department for acute urinary retention with benign prostatic hyperplasia were more likely to be older, of nonwhite race, have Medicare or private insurance, and live in more urban areas. These data suggest that African American and Hispanic patients may be untreated or under treated for benign prostatic hyperplasia in the outpatient setting, resulting in an increased risk of presentation to the emergency department with acute urinary retention.

Efficacy and Safety of Mirabegron versus Placebo Add-On Therapy in Men with Overactive Bladder Symptoms Receiving Tamsulosin for Underlying Benign Prostatic Hyperplasia: A Randomized, Phase 4 Study (PLUS).

PURPOSE: PLUS investigated the efficacy and safety of mirabegron add-on therapy in men with overactive bladder symptoms receiving tamsulosin for underlying lower urinary tract symptoms attributable to benign prostatic hyperplasia. MATERIALS AND METHODS: In this phase 4 study a 4-week 0.4 mg tamsulosin run-in period was followed by a 12-week, randomized, double-blind, treatment period in which patients initially received 25 mg mirabegron or placebo add-on therapy. At 4 weeks doses were titrated to 50 mg mirabegron or placebo equivalent. Efficacy end points were changes from baseline to end of treatment in mean number of micturitions per day (primary), mean volume voided per micturition, number of urgency episodes per day, total urgency and frequency score, and total International Prostate Symptom Score (secondary). Safety assessments included treatment emergent adverse events, and post-void residual volume, and maximum urinary flow measurements. RESULTS: Of the 676 men most were 65 years old or older (380, 56.2%). Tamsulosin plus mirabegron was statistically superior to tamsulosin plus placebo in reducing the mean number of micturitions per day (-2.00 vs -1.62; adjusted difference -0.39; 95% CI -0.76, -0.02). Statistically superior results were noted for tamsulosin plus mirabegron in mean volume voided per micturition, urgency episodes per day, and total urgency and frequency score (not International Prostate Symptom Score). Higher overall treatment emergent adverse event rates were observed with tamsulosin plus placebo, although higher rates of drug related treatment emergent adverse events were noted with tamsulosin plus mirabegron. Urinary retention rates were higher in the tamsulosin plus mirabegron group. Post-void residual volume and maximum urinary flow results were not clinically meaningful. CONCLUSIONS: The results of PLUS underscore the utility of mirabegron add-on therapy to treat men with overactive bladder symptoms receiving tamsulosin for benign prostatic hyperplasia.

Use of Surgery for Post-Prostatectomy Incontinence.

PURPOSE: Stress urinary incontinence following radical prostatectomy is common and potentially debilitating. Surgical therapy with a urethral sling or an artificial urinary sphincter is an effective option with high patient satisfaction in men in whom conservative measures fail to treat post-prostatectomy incontinence. We sought to characterize the contemporary utilization of surgical therapy of post-prostatectomy incontinence using an all payer database. MATERIALS AND METHODS: We used the Healthcare Cost and Utilization Project databases for Florida from 2006 to 2015 and identified men who underwent radical prostatectomy between 2006 and 2012 using ICD procedure codes. Patients were tracked longitudinally for placement of an ambulatory or inpatient urethral sling, or an artificial urinary sphincter between 2006 and 2015. Patient and clinical data were extracted and analyzed with descriptive statistics. A multivariable logistic regression model was constructed to determine risk adjusted predictors of subsequent incontinence surgery. RESULTS: During the study period 29,287 men underwent radical prostatectomy, of whom 1,068 (3.6%) were treated with subsequent incontinence surgery a median of 23.5 months after prostatectomy. On multivariate analysis risk factors for incontinence surgery included age groups 61 to 70 years (OR 1.25, p=0.008) and 71 to 80 years (OR 1.34, p=0.022), Medicare insurance (OR 1.33, p <0.005) and an increased Charlson Comorbidity Index (OR 1.13 per unit increase, p <0.005). CONCLUSIONS: Of patients who underwent radical prostatectomy 3.6% subsequently underwent stress urinary incontinence surgery. Post-prostatectomy incontinence surgery is likely under performed and delayed in performance based on the previously reported prevalence of severe post-prostatectomy incontinence and the natural history of symptoms. Efforts to increase prompt repair of refractory or severe incontinence can greatly improve patient quality of life after radical prostatectomy.

Penile Prosthesis Implantation and Timing Disparities After Radical Prostatectomy: Results From a Statewide Claims Database.

BACKGROUND: Many patients with erectile dysfunction (ED) after radical prostatectomy (RP) improve with conservative therapy but some do not; penile prosthesis implantation rates have been sparsely reported, and have used nonrepresentative data sets. AIM: To characterize rates and timing of penile prosthesis implantation after RP and to identify predictors of implantation using a more representative data set. METHODS: The Healthcare Cost and Utilization Project State Inpatient and State Ambulatory Surgery databases for Florida from 2006 to 2015 were used. Patients undergoing RP (2006-2012) were tracked longitudinally for penile prosthesis implantation. Patient and clinical data were analyzed using multivariable logistic regression. OUTCOMES: The primary outcome was risk-adjusted predictors of prosthesis implantation, and the secondary outcome was predictors of the highest quartile of time between RP and penile prosthesis. RESULTS: Of 29,288 men who had RP, 1,449 (4.9%) patients underwent subsequent prosthesis. The mean time from RP to prosthesis was 2.6 years (median: 2.1; interquartile range [IQR]: 1.2-3.5). Adjusted predictors of prosthesis implantation included open RP (odds ratio [OR]: 1.5, P < .01), African American race (OR: 1.7, P < .01) or Hispanic ethnicity (OR: 3.2, P < .01), and Medicare (OR: 1.4, P < .01) insurance. Oler patients (age >70 years; OR: 0.7, P < .01) and those from the highest income quartile relative to the lowest (OR: 0.8, P < .05) were less likely to be implanted. Adjusted predictors of longer RP-to-implantation time (highest quartile: median: 4.7 years; IQR: 3.9-6.0 years) included open RP (OR: 1.78, P < .01), laparoscopic RP (OR: 4.67, P < .01), Medicaid (OR: 3.03, P < .05), private insurance (OR: 2.57, P < .01), and being in the highest income quartile (OR: 2.52, P < .01). CLINICAL IMPLICATIONS: These findings suggest ED treatment healthcare disparities meriting further investigation; upfront counseling on all ED treatment modalities and close monitoring for conservative treatment failure may reduce lost quality of life years. STRENGTHS & LIMITATIONS: This study is limited by its use of administrative data, which relies on accurate coding and lacks data on ED questionnaires/prior treatments, patient-level cost, and oncologic outcomes. Quartile-based analysis of income and time between RP and prosthesis limits the conclusions that can be drawn. CONCLUSION: Less than 5% of post-RP patients undergo penile prosthesis implantation, with open RP, Medicare, African American race, and Hispanic ethnicity predicting post-RP implantation; living in the wealthiest residential areas predicts lower likelihood of implantation compared to the least wealthy areas. Patients with the longest time between RP and prosthesis are more likely to live in the wealthiest areas or have undergone open/laparoscopic RP relative to robotic RP. Bajic P, Patel PM, Nelson MH, et al. Penile Prosthesis Implantation and Timing Disparities After Radical Prostatectomy: Results From a Statewide Claims Database. J Sex Med 2020;17:1175-1181.

The New American Urological Association Benign Prostatic Hyperplasia Clinical Guidelines: 2019 Update.

PURPOSE OF REVIEW: The goal of this paper was to analyze the efficacy of the current modalities available to surgically treat lower urinary tract symptoms (LUTS) associated with benign prostatic hyperplasia (BPH). RECENT FINDINGS: There have been significant surgical advancements for the treatment of BPH, including an increasing development and utilization of minimally invasive surgical techniques (MISTs). These procedures have varying outcomes that are critical to understand. In addition, MISTs have important adverse effects, though have minimized effects on sexual function when compared to more invasive surgical techniques. It is important for all urologists to be familiar with the surgical techniques available to treat BPH and the updated American Urological Association (AUA) Guidelines. Further studies evaluating efficacy, safety, and sexual functioning will help guide care in the future and evolve practice.