Persistent storage symptoms following Y-V plasty reconstruction for the treatment of refractory bladder neck contracture.

PURPOSE: Refractory bladder neck contracture (BNC) following transurethral prostatectomy is rare and difficult to manage. Success rate of endoscopic treatment decline considerably after repeated treatments. Bladder neck reconstruction are often the last resort to treat refractory BNC failing endoscopic treatments. In general, experience is limited with this type of bladder neck reconstruction, particularly in adult patients. This study aims to determine the success rate, functional and patient-reported outcomes (PRO) of open Y-V plasty in treatment of refractory BNC after transurethral prostatectomy. The study also aims to determine the rate, and potential predictors of persistent storage symptoms after Y-V plasty. MATERIALS AND METHODS: Between January 2016 and February 2021, 18 consecutive patients with refractory BNC who underwent open Y-V plasty were included in this study. All patients presented with voiding dysfunction after two or more failed attempts of endoscopic treatments followed by a 3-month period of outpatient serial dilation program. Clinicopathological data were extracted from medical records including baseline demographics, aetiology of BNC, previous endoscopic treatment, operative time, length of stay, complications, uroflow findings, International Prostate Symptom Score (IPSS) and OAB-V8. Primary outcome was the success of open YV plasty, defined as no need for further instrumentation such as indwelling catheterization, urethral dilatation, urethrotomy, or open surgery. Simple linear regression analysis was performed to determine predictor factors for postoperative OAB-V8. Variables that showed p < 0.25 were included in the multiple linear regression analysis. RESULTS: Most common aetiology of BNC was transurethral resection of prostate gland (n = 18, 100%). Mean age at surgery age (SD) was 65.5 (7.3) years. Mean follow-up was 14.8 (7) months. Success rate was 100%. Postoperative Qmax improved significantly [pre-OP 6.7 (8.1) ml/s vs. post-OP was 14.8 (7.3) ml/s, p < 0.001]. Mean postvoid residual decreased significantly [pre-OP 223.3 (254.3) ml vs. post-OP 45.1 (71.0) ml, p < 0.01)]. Persistent storage symptoms were reported in 61% of patients. BMI and baseline IPSS score are significant predictors for the postoperative OAB V8 change (adjusted b (95% confidence interval) = 1.037 (0.2-1.9), 0.64 (0.28-0.99), respectively, R2 = 0.59). CONCLUSION: Y-V plasty reconstruction for refractory BNC represents a feasible and successful option with high success rate and favorable outcomes. While functional and patient-reported outcomes had significantly improved post-operatively, persistent storage symptoms after this procedure still exist. BMI and baseline IPSS score are significant predictors for persistent storage symptoms after bladder neck reconstruction.

Imbalance of nerve growth factor metabolism in aging women with overactive bladder syndrome.

PURPOSE: Given the disputable link between nerve growth factor (NGF) and overactive bladder syndrome (OAB) and the lack of studies on its precursor (proNGF) in OAB, the aim of the study was to identify changes in the urinary levels of NGF and its proteolytic enzymes in aging women with OAB. METHODS: We examined the urinary proNGF/NGF ratio and its processing enzymes in aging women (50-80 years), comparing 20 controls and 20 subjects with OAB. RESULTS: In contrast to previous reports correlating NGF to OAB symptoms, we found that proNGF/NGF ratio in the OAB group was twice as high compared to controls (p = 0.009) with a lower NGF levels in women with OAB without statistical significance [1.36 (Q1, Q3: 0.668, 2.39) vs. 1.7 (Q1, Q3: 1.27, 3.045) pg/mg creatinine in control group, p = 0.05]. Enzymatic activity of MMP-7, the main enzyme for extracellular proNGF maturation, was significantly increased in the OAB group and correlated positively with scores of OAB symptoms questionnaires. However, this was counteracted by several-folds increase in the MMP-9 enzyme responsible for NGF proteolysis. While these findings highlight the importance of changes in the proteolytic enzymes to maintain proNGF/NGF balance in OAB, analysis of covariates showed that these changes were attributed to age, insulin resistance and renal function. CONCLUSION: NGF proteolysis imbalance can be clinically meaningful in OAB related to aging, rendering it as a potential therapeutic target. However, other age-related factors such as insulin resistance and renal function may contribute to the relationship between NGF and aging-related OAB phenotype.

Osr1 Is Required for Mesenchymal Derivatives That Produce Collagen in the Bladder.

The extracellular matrix of the bladder consists mostly of type I and III collagen, which are required during loading. During bladder injury, there is an accumulation of collagen that impairs bladder function. Little is known about the genes that regulate production of collagens in the bladder. We demonstrate that the transcription factor Odd-skipped related 1 (Osr1) is expressed in the bladder mesenchyme and epithelium at the onset of development. As development proceeds, Osr1 is mainly expressed in mesenchymal progenitors and their derivatives. We hypothesized that Osr1 regulates mesenchymal cell differentiation and production of collagens in the bladder. To test this hypothesis, we examined newborn and adult mice heterozygous for Osr1, Osr1+/-. The bladders of newborn Osr1+/- mice had a decrease in collagen I by western blot analysis and a global decrease in collagens using Sirius red staining. There was also a decrease in the cellularity of the lamina propria, where most collagen is synthesized. This was not due to decreased proliferation or increased apoptosis in this cell population. Surprisingly, the bladders of adult Osr1+/- mice had an increase in collagen that was associated with abnormal bladder function; they also had a decrease in bladder capacity and voided more frequently. The results suggest that Osr1 is important for the differentiation of mesenchymal cells that give rise to collagen-producing cells.

Antagonism of proNGF or its receptor p75NTR reverses remodelling and improves bladder function in a mouse model of diabetic voiding dysfunction.

AIMS/HYPOTHESIS: Although 80% of diabetic patients will suffer from voiding difficulties and urinary symptoms, defined as diabetic voiding dysfunction (DVD), therapeutic targets and treatment options are limited. We hypothesise that the blockade of the pro-nerve growth factor (NGF)/p75 neurotrophin receptor (p75NTR) axis by an anti-proNGF monoclonal antibody or by a small molecule p75NTR antagonist (THX-B) can restore bladder remodelling (represented by bladder weight) in an animal model of DVD. Secondary outcomes of the study include improvements in bladder compliance, contractility and morphology, as well as in voiding behaviour, proNGF/NGF balance and TNF-α expression. METHODS: In a streptozotocin-induced mouse model of diabetes, diabetic mice received either a blocking anti-proNGF monoclonal antibody or a p75NTR antagonist small molecule as weekly systemic injections for 4 weeks. Animals were tested at baseline (at 2 weeks of diabetes induction), and after 2 and 4 weeks of treatment. Outcomes measured were voiding function with voiding spot assays and cystometry. Bladders were assessed by histological, contractility and protein expression assays. RESULTS: Diabetic mice showed features of DVD as early as 2 weeks after diabetes diagnosis (baseline) presented by hypertrophy, reduced contractility and abnormal cystometric parameters. Following treatment initiation, a twofold increase (p < 0.05) in untreated diabetic mouse bladder weight and thickness compared with non-diabetic controls was observed, and this change was reversed by p75NTR antagonism (37% reduction in bladder weight compared with untreated diabetic mice [95% CI 14%, 60%]) after 4 weeks of treatment. However, blocking proNGF did not help to reverse bladder hypertrophy. While diabetic mice had significantly worse cystometric parameters and contractile responses than non-diabetic controls, proNGF antagonism normalised bladder compliance (0.007 [Q1-Q3; 0.006-0.009] vs 0.015 [Q1-Q3; 0.014-0.029] ml/cmH2O in untreated diabetic mice, representing 62% reduction [95% CI 8%, 110%], p < 0.05) and contractility to KCl, carbachol and electrical field stimulation (p < 0.05 compared with the diabetic group) after 2 weeks of treatment. These effects were not observed after 4 weeks of treatment with proNGF antagonist. p75NTR antagonism did not show important improvements in cystometric parameters after 2 weeks of treatment. Slightly improved bladder compliance (0.01 [Q1-Q3; 0.009-0.012] vs 0.013 [Q1-Q3; 0.011-0.016] ml/cmH2O for untreated diabetic mice) was seen in the p75NTR antagonist-treated group after 4 weeks of treatment with significantly stabilised contractile responses to KCl, carbachol and electric field stimulation (p < 0.05 for each) compared with diabetic mice. Bladder dysfunction observed in diabetic mice was associated with a significant increase in bladder proNGF/NGF ratio (3.1 [±1.2] vs 0.26 [±0.04] ng/pg in control group, p < 0.05 at week 2 of treatment) and TNF-α (p < 0.05). The proNGF/NGF ratio was partially reduced (about 60% reduction) with both treatments (1.03 [±0.6] ng/pg for proNGF antibody-treated group and 1.4 [±0.76] ng/pg for p75NTR blocker-treated group after 2 weeks of treatment), concomitant with a significant decrease in the bladder levels of TNF-α (p < 0.05), despite persistent hyperglycaemia. CONCLUSIONS/INTERPRETATION: Our findings indicate that blockade of proNGF and the p75NTR receptor in diabetes can impede the development and progression of DVD. The reported improvements in morphological and functional features in our DVD model validates the proNGF/p75NTR axis as a potential therapeutic target in this pathology. Graphical abstract.

Urinary metabolomics predict the severity of overactive bladder syndrome in an aging female population.

INTRODUCTION AND HYPOTHESIS: To identify urinary metabolites that can facilitate the diagnosis and the characterization of the underlying pathophysiology of the association between the overactive bladder syndrome (OAB) and metabolic syndrome. METHODS: We used gas chromatography-mass spectrometry to compare the urinary metabolome of 20 females of 50-80 years of age with OAB to that of 20 controls of the same age group. We performed urinary metabolomic analysis and obtained serum markers of metabolic syndrome for each subject. Participants completed a clinical evaluation and validated self-reported questionnaires of lower urinary tract symptoms as well as a one-day voiding diary. RESULTS: In the OAB subjects, we identified increased urinary levels of markers of mitochondrial dysfunction (itaconate, malate and fumarate), oxidative stress (L-pyroglutamate and α-hydroxyglutarate) and ketosis (α-hydroxybutyrate and α-hydroxyisobutyrate). The increased levels of these markers correlated significantly with the OAB symptoms score on questionnaires. We found, using a multiple linear regression model, that age, blood glucose and urine metabolites (malate, fumarate and α-hydroxyisobutyrate) were significant predictive factors of OAB severity. Fumarate had high sensitivity as a biomarker of OAB due to metabolic syndrome, based on a statistically significant receiver-operating characteristic (ROC) curve, indicating its potential as a diagnostic tool. CONCLUSIONS: Altogether, these findings establish that urinary metabolites of mitochondrial dysfunction, ketosis and oxidative stress can be potential biomarkers of OAB severity and diagnosis.

Are Beta 3 Adrenergic Agonists Now the Preferred Pharmacologic Management of Overactive Bladder?

PURPOSE OF THE REVIEW: This paper discusses the recent evidence supporting beta 3 adrenergic agonists as the preferred pharmacological management of overactive bladder syndrome. RECENT FINDINGS: Mirabegron has a similar efficacy profile to first-line antimuscarinics with favorable adverse effects profile. Treatment of OAB with beta-3 adrenergic agonist should be favored in patients at higher risk of anticholinergic adverse events. The efficacy and tolerability of beta-3 adrenergic agonists are consistently reported in older OAB patients, whether used alone or with other antimuscarinics. Mirabegron is cost-effective in treating OAB unless the symptoms were severe or refractory. Combination therapy of mirabegron and other pharmacotherapy has proven to be efficient in controlling OAB symptoms without inducing serious add-on adverse effects. While beta-3 adrenergic agonists bear favorable advantages in OAB treatment, physicians should perform a thorough and careful pre-treatment planning to optimize treatment benefits and adherence.

Bladder overdistension with polyuria in a hypertensive rat model.

AIMS: Polyuria can lead to progressive chronic bladder overdistension. The impact of polyuria on the bladder has been extensively studied in settings of either diabetes or sucrose diuresis in animals. The goal of this study was to investigate the outcomes of polyuria in a hypertension setting. MATERIALS AND METHODS: Male Dahl/SS rats, a hypertension model, received a high-salt or normal diet for 6 weeks. Twenty-four-hour water intake, micturition patterns, and blood pressures were recorded biweekly. Conscious cystometry was carried out at the end of this period. Bladders were collected to measure contractile force and for histological analysis. Paired t-tests were used to compare changes between Week 0 and Week 6 within each group. Unpaired t-tests were used for comparisons between groups for all parameters at Week 6. RESULTS: Six weeks of high-salt diet significantly increased water intake and total urine. Blood pressures and volume of urine per micturition was higher in rats on high-salt diet. Bladder overdistension in the high-salt diet group was confirmed by cystometry, shown by a significantly higher bladder capacity, and compliance. No difference in detrusor contractility was observed between both groups. Collagen content was significantly higher in the lamina propria of the high-salt group compared to the normal group, while the opposite was observed in the muscularis. CONCLUSIONS: Polyuria, in a hypertension context, leads to changes in bladder morphology and function. These findings help clarify the deleterious clinical impact of polyuria on voiding function, highlighting the variable consequences of bladder overdistension according to the underlying pathology.

Succinate decreases bladder function in a rat model associated with metabolic syndrome.

AIMS: Succinate and its receptor, GPR91, have been implicated in different aspects of metabolic syndrome. As GPR91 is expressed in the urinary bladder, the aim of this study is to show the effect of chronically increased succinate levels on bladder function. MATERIALS AND METHODS: Healthy Sprague-Dawley (SD) rats and hypertensive Dahl rats received an intraperitoneal injection of either saline or succinate (50 mg/kg) daily for a period of 4 weeks. Conscious cystometry was performed at the end of this period. Bladders were collected and used for contractility studies and morphological assessment. Two-way ANOVA was performed to compare between the two strains and student t-tests to compare treatment groups within each strain. RESULTS: Compared to SD rats, Dahl rats showed signs of bladder dysfunction. Succinate treatment led to higher urinary succinate levels and lower bladder capacities compared to saline-treated animals. In SD rats, this was associated with higher collagen content, lower GPR91 expression and an altered bladder nerve profile in the bladder. In succinate-treated Dahl rats, detrusor contractility was reduced and associated with decreased cholinergic innervation and increased collagen content. CONCLUSIONS: It is suggested that succinate negatively affects bladder function via effects through its receptor, GPR91, and that its effects are enhanced in the presence of metabolic disturbance. These findings contribute to our understanding of the pathophysiology of bladder dysfunction, specifically in a metabolic syndrome setting.

Characterizing the Inflammatory Profile of Neutrophil-Rich Triple-Negative Breast Cancer.

Breast cancer (BC) is one of the most common types of cancer in women in the United Arab Emirates. Immunogenic tumours, such as triple-negative breast cancer (TNBC), show increased neutrophil infiltration, which is associated with poor prognosis and limited efficacy of immunotherapy. This study aims to investigate in vitro the bidirectional effect of neutrophils on metastatic TNBC (MDA-MB-231) compared to less-metastatic luminal breast cancer (MCF-7) cell lines. We found that BC cells or their conditioned medium (CM) reduced the viability of neutrophil-like cells (HL60). This was supported by increased cellular stress and NETosis in differentiated HL60 cells (dHL60) upon exposure to MDA-MB-231 compared to MCF-7-CM using nucleic acid staining essays. Flow cytometry showed comparable expression of inflammatory markers by polymorphonuclear cells (PMN) when treated with MDA-MB-231-CM and standard polarizing cocktails. Furthermore, MDA-MB-231-CM triggered an inflammatory pattern with evidence of stronger adhesion (CD62L) and degranulation (CD11b and CD66b) phenotypes. The proinflammatory polarization of dHL60 by MDA-MB-231-CM was additionally confirmed by the elevated CD54 expression, myeloperoxidase, and CD11b protein levels, which matched an increased transwell migratory capacity. In conclusion, BC might use neutrophils to their benefit through NETosis and complement system activation, which makes this crosstalk a potential mechanism for understanding tumour progression.

Urinary Levels of miR-491-5p and miR-592 as Potential Diagnostic Biomarkers in Female Aging Patients with OAB: A Pilot Study.

Women with overactive bladder syndrome (OAB) have a lower urinary ratio of nerve growth factor (NGF) to its precursor (proNGF) compared to healthy controls. MicroRNAs related to NGF and proNGF metabolism and to their receptors may be present in urine and may possess diagnostic value. Urine and blood samples from 20 control and 20 OAB women (50-80 years) were obtained, together with validated questionnaires and other clinical parameters. The relative expression of urinary microRNAs was measured with RT-qPCR. MiR-491-5p, which negatively controls the translation of the matrix metalloproteinase-9 (MMP-9), the main enzyme degrading NGF, was significantly decreased in OAB. Similarly, miR-592, which represses p75NTR receptor synthesis, was down-regulated in OAB. Age, renal function and insulin resistance did not affect these results. ROC curves confirmed the high sensitivity of miR-491-5p and miR-592 for diagnosis. On the other hand, miRNAs involved in the expression of proNGF, of survival receptor TrkA and of markers of nerve integrity were similar between groups. The detection of miR-491-5p and miR-592 in urine could be a useful and non-invasive tool for the diagnosis of OAB syndrome in aging women.

Modulation of diabetic kidney disease markers by an antagonist of p75NTR in streptozotocin-treated mice.

Two therapeutic agents targeting p75NTR pathways have been recently developed to alleviate retinopathy and bladder dysfunction in diabetes mellitus (DM), namely the small molecule p75NTR antagonist THX-B and a monoclonal antibody (mAb) that neutralizes the receptor ligand proNGF. We herein explore these two components in the context of diabetic kidney disease (DKD). Streptozotocin-injected mice were treated for 4 weeks with THX-B or anti-proNGF mAb. Kidneys were taken for quantification of microRNAs and mRNAs by RT-qPCR and for detection of proteins by immunohistochemistry, immunoblotting and ELISA. Blood was sampled to measure plasma levels of urea, creatinine, and albumin. DM led to increases in plasma concentrations of urea and creatinine and decreases in plasma albumin. Receptor p75NTR was expressed in kidneys and its expression was decreased by DM. All these changes were reversed by THX-B treatment while the effect of mAb was less pronounced. MicroRNAs tightly linked to DKD (miR-21-5p, miR-214-3p and miR-342-3p) were highly expressed in diabetic kidneys compared to healthy ones. Also, miR-146a, a marker of kidney inflammation, and mRNA levels of Fn-1 and Nphs, two markers of fibrosis and inflammation, were elevated in DM. Treatments with THX-B or mAb partially or completely reduced the expression of the aforementioned microRNAs and mRNAs. P75NTR antagonism and proNGF mAb might constitute new therapeutic tools to treat or slow down the progression of kidney disease in DM, along with other diabetic related complications. The translational potential of these strategies is currently being investigated.

Promoting more future-ready anatomy education after the Covid-19 pandemic: A scoping review.

The coronavirus disease 2019 (Covid-19) pandemic caused an abrupt transition from face-to-face to online anatomy teaching, learning, and assessment. Although online education has ensured the continuity of anatomy education during the pandemic, its implementation has been challenging, and its effectiveness has been questioned. Therefore, literature pertinent to online anatomy education during the pandemic is crucial to explain Covid-19's disruptions to this field. Accordingly, this scoping review explored changes, disruptions, and gaps in anatomy teaching and assessment during Covid-19 using an enhanced version of Arksey and O'Malley's six-stage protocol. Five online databases were searched for articles that described changes and disruptions in anatomy education. Three independent researchers were involved in titles, abstracts, and full texts screening, while another four researchers were independently involved in data extraction, charting, and synthesis. This review revealed six themes: immediate strategic plans and actions, teaching and learning changes, online assessment practice, students' and educators' receptivity and adaptability, online learning and assessment effects, and future directions. It also revealed four gaps: non-future-ready curricula, learning obstacles, administrative and teaching challenges, and online education ethical issues. The results were reported in tabular and narrative forms, following the PRISMA Extension for Scoping Reviews (PRISMA-ScR guidelines). Understanding the evolution and gaps in anatomy education during the Covid-19 pandemic will help anatomists design future-ready, adaptable curricula.

Deleterious impact of nerve growth factor precursor (proNGF) on bladder urothelial and smooth muscle cells.

The nerve growth factor precursor (proNGF) activates p75NTR receptor and promotes cell death in different tissues, yet this pathophysiological effect is not fully described in the bladder. The aim of this study was to identify the biological effect of proNGF/p75NTR activation on urothelial and smooth muscle (SM) cells of rodents' bladder. Cell viability was assessed by MTT assay which showed a significant reduction in urothelial viability after 24 h of incubation with proNGF in culture medium [5 or 10 nM], an effect not seen in SM cells. Western blot analysis on cellular protein extracts showed increased expression of the transmembrane TNF-α and activation of RhoA in urothelial cells exposed to proNGF with no evidence of a nuclear translocation of NF-κB assessed by western blotting on nuclear extracts and immunofluorescence. The activation of p75NTR-death domain related pathways in urothelial cells such as TNF-α or RhoA had a downstream effect on NO release and the junctional protein occludin, as estimated respectively by colorimetric and western blotting. On the other hand, proNGF did not induce TNF-α or RhoA expression in SM cells, but induced a significant NF-κB nuclear translocation. ProNGF had a different impact on SM as evidenced by a significant dose- and time-dependent increase in SM proliferation and migration examined by MTT test and cell migration assay. Together, our results indicate that activation of proNGF/p75NTR axis induces degenerative changes to the urothelial layer impacting its barrier and signaling integrity, while promoting adaptive proliferative changes in detrusor SM cells that can interfere with the contractile phenotype essential for proper bladder function.

Succinate, increased in metabolic syndrome, activates GPR91 receptor signaling in urothelial cells.

Metabolic syndrome is associated with overactive bladder syndrome (OAB) and increased circulating levels of succinate, an intermediate of the Krebs cycle. The urothelium is an essential regulator of bladder muscle contraction. This study aimed to determine if GPR91, the succinate receptor, is expressed and functional in the bladder. Urothelial and smooth muscle cells (SMCs) were cultured and characterized. PCR revealed that urothelial cells express GPR91, twice as much as SMCs. Incubation of cells with succinate stimulated phosphorylation of ERK and JNK in urothelial cells. Succinate also potently inhibited forskolin-stimulated cyclic AMP production in urothelial cells, an effect prevented by a protein Gi inhibitor. ERK phosphorylation stimulated by succinate was abolished by inhibitors of protein Gq, phospholipase C, MAPK pathway and PKC. Incubation of urothelial cells with succinate potently increased iNOS synthesis and secretion of nitric oxide (NO), and decreased secretion of prostaglandin E2 (PGE2). Finally, succinate triggered entry of calcium in urothelial cells. GPR91 knockdown by shRNA abolished most of these signaling effects. We conclude that in the bladder, urothelial cells are a primary target of succinate through its receptor GPR91. Its activation leads to signaling via phospholipase C, MAPK, PKC pathway and protein Gq and Gi. Succinate binding to GPR91 triggers a rise in intracellular calcium, an increase in secretion of NO and a decrease in the release of PGE2. Succinate might be essential in the understanding of OAB that occurs in metabolic syndrome.