Urinary Nerve Growth Factor Levels in Overactive Bladder Syndrome and Lower Urinary Tract Disorders

Urinary beta 3-adrenoceptor as a diagnostic biomarker for overactive bladder in women

This study was to investigate urinary beta 3-adrenoceptor concentration as a biomarker for overactive bladder (OAB) and predictor of treatment outcomes in women receiving the beta 3-adrenoceptor agonist mirabegron. The study comprised 50 women identified with OAB and 35 women considered as healthy controls. All women with OAB received daily dosage of 50 mg of mirabegron for 12 weeks. Bladder diaries, OAB-related questionnaires, and global response assessment scale (GRAS) data were collected. Urinary beta 3-adrenoceptor concentration was measured through enzyme-linked immunosorbent assay. All OAB-related questionnaires and GRAS indicated improved posttreatment urinary health. After mirabegron treatment, the frequency of micturition and urgency episodes decreased, but the urinary beta 3-adrenoceptor/creatinine (Cr) ratio increased. The urinary beta 3-adrenoceptor/creatinine ratio was identified as a sensitive biomarker for OAB with a confidence interval of 0.656 to 0.856 (p < 0.001). A negative correlation (- 0.431, p = 0.040) between this biomarker and health-related quality of life (HRQL) scores. The Beta 3-adrenoceptor/Cr levels increased significantly in the treatment-responsive group, while they remained unchanged in the unsatisfactory outcome group. This study shows that 12 weeks of mirabegron treatment improves OAB symptoms and HRQL. Furthermore, urinary beta 3-adrenoceptor concentration may be a diagnostic biomarker for OAB.

Functional recovery of injured cavernous nerves achieved through endogenous nerve growth factor-containing bioactive fibrous membrane

Radical prostatectomy is a highly successful treatment for prostate cancer, among the most prevalent manifestations of the illness. Damage of the cavernous nerve (CN) during prostatectomy is the main cause of postoperative erectile dysfunction (ED). In this study, the capability of a personalized bioactive fibrous membrane to regenerate injured CN was investigated. The fibrous membrane bioactivity is conferred by the selectively bound nerve growth factor (NGF) present in the rat urine. In a rat model of bilateral CN crush, the implanted bioactive fibrous membrane induces CN regeneration and restoration of erectile function, showing a significantly increased number of smooth muscle cells and content of endothelial and neuronal nitric oxide synthases (eNOS; nNOS). In addition, the bioactive fibrous membrane promotes nerve regeneration by increasing the number of myelinated axons and nNOS-positive cells, therefore reversing the CN fibrosis found in untreated rats or rats treated with a bare fibrous membrane. Therefore, this personalized regenerative strategy could overcome the recognized drawbacks of currently available treatments for CN injuries. It may constitute an effective treatment for prostate cancer patients suffering from ED after being subject to radical prostatectomy. STATEMENT OF SIGNIFICANCE: The present work introduces a unique strategy to address post-surgical ED resulting from CN injury during pelvic surgery (e.g., radical prostatectomy, radical cystoprostatectomy, abdominoperineal resection). It comprises a bioactive and cell-free fibrous implant, customized to enhance CN recovery. Pre-clinical results in a rat model of bilateral CN crush demonstrated that the bioactive fibrous implant can effectively heal injured CN, and restore penile structure and function. This implant selectively binds NGF from patient fluids (i.e. urine) due to its functionalized surface and high surface area. Moreover, its local implantation reduces adverse side effects. This tailored regenerative approach has the potential to revolutionize the treatment of ED in prostate cancer patients following radical prostatectomy, overcoming current treatment limitations.

Effectiveness of Platelet-Rich Plasma Injections as Prophylaxis for Recurrent Urinary Tract Infection in Women

PURPOSE

To investigate the therapeutic efficacy of intravesical platelet-rich plasma (PRP) injections as prophylaxis for adult women with recurrent urinary tract infection (rUTI).

METHODS

This proof-of-concept study enrolled 63 women with rUTI in PRP treatment and control groups after achieving control of the most recent urinary tract infection (UTI) episode. The treatment group included 34 women who received 4 monthly intravesical PRP injections. The control group was made up of 30 women who received continuous antibiotic treatment for 3 months. After the completion of PRP or antibiotic treatment, outpatient follow-up was continued for up to 12 months. Treatment was considered successful if ≤2 UTI episodes occurred during a period of 12 months or ≤1 UTI episode within 6 months; otherwise, the outcome was considered a treatment failure. The frequency of symptomatic UTI episodes before and after PRP treatment was compared with that of the controls. Regression analysis was used to determine the association between potential predictors for a failed treatment outcome.

RESULTS

At the study endpoint, 33 PRP and 25 control group patients were available for analysis. After four PRP injections, the frequency of rUTI episodes per month was significantly decreased compared with baseline (0.46 ± 0.27 vs. 0.28 ± 0.30, p = 0.047). The PRP treatment success rate was 51.5% (17 of 33) for the PRP group versus 48% (12 of 25) for the control group. The PRP treatment success group had significantly higher voided volume, lower post-void residual volume, and higher voiding efficiency than the PRP treatment failure group. A higher baseline voiding efficacy ≥0.71 was significantly associated with a successful outcome (OR 16.56; p = 0.049).

CONCLUSIONS

The study results revealed that repeat intravesical PRP injections decreased the recurrence rate of UTI within 1 year in women with rUTI. The treatment success rate with intravesical PRP injections for rUTI was about 51.5%, whereas for women with prolonged antibiotic treatment, it was 48.0%. A baseline VE ≥ 0.71 was associated with a better treatment outcome with PRP injections.

Stress-induced symptom exacerbation: Stress increases voiding frequency, somatic sensitivity, and urinary bladder NGF and BDNF expression in mice with subthreshold cyclophosphamide (CYP)

Symptom exacerbation due to stress is prevalent in many disease states, including functional disorders of the urinary bladder (e.g., overactive bladder (OAB), interstitial cystitis/bladder pain syndrome (IC/BPS)); however, the mechanisms underlying the effects of stress on micturition reflex function are unclear. In this study we designed and evaluated a stress-induced symptom exacerbation (SISE) mouse model that demonstrates increased urinary frequency and somatic (pelvic and hindpaw) sensitivity. Cyclophosphamide (CYP) (35 mg/kg; i.p., every 48 hours for a total of 4 doses) or 7 days of repeated variate stress (RVS) did not alter urinary bladder function or somatic sensitivity; however, both CYP alone and RVS alone significantly (p ≤ 0.01) decreased weight gain and increased serum corticosterone. CYP treatment when combined with RVS for 7 days (CYP+RVS) significantly (p ≤ 0.01) increased serum corticosterone, urinary frequency and somatic sensitivity and decreased weight gain. CYP+RVS exposure in mice significantly (p ≤ 0.01) increased (2.6-fold) voiding frequency as we determined using conscious, open-outlet cystometry. CYP+RVS significantly (p ≤ 0.05) increased baseline, threshold, and peak micturition pressures. We also evaluated the expression of NGF, BDNF, CXC chemokines and IL-6 in urinary bladder in CYP alone, RVS alone and CYP+RVS mouse cohorts. Although all treatments or exposures increased urinary bladder NGF, BDNF, CXC and IL-6 content, CYP+RVS produced the largest increase in all inflammatory mediators examined. These results demonstrated that CYP alone or RVS alone creates a change in the inflammatory environment of the urinary bladder but does not result in a change in bladder function or somatic sensitivity until CYP is combined with RVS (CYP+RVS). The SISE model of CYP+RVS will be useful to develop testable hypotheses addressing underlying mechanisms where psychological stress exacerbates symptoms in functional bladder disorders leading to identification of targets and potential treatments.

Diagnostic value of nerve growth factor in detrusor overactivity: a study on women with mixed urinary incontinence

OBJECTIVE

Urinary incontinence has a profound impact on women's quality of life. Studies have shown that changes in urinary protein levels could be a potential diagnostic biomarker in some urological diseases. The aim of present study is to determine the diagnostic value of nerve growth factor (NGF) in women with mixed urinary incontinence (MUI) as a diagnostic biomarkers of detrusor overactivity (DO).

METHODS

Seventy women aged between 20 and 75 years with MUI were enrolled in this prospective study. All participants underwent urodynamic study. Urine NGF levels were measured using an ELISA method. NGF level was compared between groups using Mann-Whitney U test. Receiver Operator Characteristic (ROC) analysis was employed to evaluate the diagnostic performance of urinary NGF.

RESULTS

The results showed that the median (min, max) of NGF in patients with DO was significantly higher in comparing to its level in women without DO [184.10 (31, 346.60) pg/ml vs. 151.80 (21, 210.70)], respectively (P = 0.035). Using receiver-operator characteristics analysis, the threshold urinary NGF value of 102.00 pg/ml provided a sensitivity of 88% and specificity of 40% in diagnosing DO, PPV of 39.1%, and NPV of 88.2%, positive likelihood ratio 2.18 and negative likelihood ratio of 0.45 (P = 0.02).

CONCLUSION

Based on high sensitivity and low specificity, we can conclude that NGF can be a good tool for ruling out the OAB when the test is negative. However, the future investigations are needed to expand the observed correlation in larger groups of women with DO.

Urothelial health after platelet-rich plasma injection in intractable recurrent urinary tract infection: Improved cell proliferation, cytoskeleton, and barrier function protein expression

OBJECTIVE

This clinical study used autologous intravesical platelet-rich plasma (PRP) injections to treat patients with recurrent urinary tract infection (rUTI). Changes in urothelial proliferation, cytoskeleton, and barrier function protein expression after treatment were investigated.

MATERIALS

All patients underwent 4-monthly intravesical PRP injections with 1-year follow-up. Successful treatment was defined as ≤2 UTI episodes within the preceding 1 year. Bladder biopsies were performed at the first and fourth PRP injection, and specimens were investigated by Western blot for the proteins sonic hedgehog (Shh), CD34, cytokeratin 5 (CK5), CK14, CK20, zonula occludens-1 (ZO-1), E-cadherin, inflammatory proteins tryptase and p38, apoptotic protein BAX (BCL2-associated X protein) and caspase-3, functional proteins M2 (muscarinic receptor 2) and M3, and beta-adrenoceptor-3, with glyceraldehyde phosphate dehydrogenase used as normalizing protein for quantification.

RESULTS

The study enrolled 22 patients with rUTI and 17 controls, with successful outcome in 14 of 22 (63.6%) patients. Compared with controls, Western blot quantification results showed that rUTI patients had lower CD34, CK20, M3, and ZO-1, but higher CK5, BAX, and caspase-3 at baseline. The reduced CD34, CK20, M2, and M3 expressions at baseline were significantly increased after repeat PRP injections. Patients with a successful outcome had significant increase of CD34, Shh, CK20, M2, and M3 expressions after PRP injections.

CONCLUSION

Intravesical PRP repeat injections improve the urothelial cell proliferation and increase the CK 20 expression in umbrella cells. PRP repeat injections have a beneficial effect on bladder urothelium-associated changes in rUTI. Thus, PRP injection may restore urothelial health and prevent UTI recurrence in intractable rUTI.

The profile of urinary biomarkers in overactive bladder

AIMS

In overactive bladder (OAB) research, different biomarkers have been proposed as diagnostic tools and may be used to create individual patient profiles. Assessing the diagnostic performance of biomarkers would better outline their utility. Therefore, our aim was to investigate the diagnostic value of four urinary biomarkers: human brain derived neurotrophic factor (hBDNF), malondialdehyde (MDA), h nerve growth factor (hNGF) and h 8-hydroxydeoxyguanosine in women with OAB. These are neurotrophins/oxidative stress markers that have been linked to lower urinary tract symptoms.

METHODS

A total of 105 women were included in the study and distributed in two groups: a group with OAB (n = 53) and a control group (n = 50). The levels of the biomarkers were determined using enzyme-linked immunosorbent assay technique and they were compared between the groups. If the Mann-Whitney test demonstrated a statistically significant difference, receiver operating curves (ROC) analysis was undertaken.

RESULTS

When normalized to urinary creatinine, hBDNF, MDA, and hNGF showed significantly increased values in women with OAB as compared to controls, whereas 8-OHdG showed no significant difference. The diagnostic performance of these biomarkers was analyzed based on the area under the ROC curve (AUC). MDA had the highest AUC (0.75), followed by hNGF (0.69) and hBDNF (0.67).

CONCLUSIONS

Our findings suggest that MDA, a relatively novel biomarker in OAB research, has a fair performance as a diagnostic tool for OAB. Moreover, urinary neurotrophins (NGF and BDNF) as biomarkers may have a role in the diagnostic pathways of women with OAB symptoms.

Immunochemical analysis on polypropylene mesh: does mesh size make a difference?

INTRODUCTION AND HYPOTHESIS

The aim of the study is to demonstrate the impact of the size of implanted mesh in relation to its immunohistochemical reaction implanted into animal models.

METHODS

An experimental study utilizing 54 female Sprague Dawley (SD) rats was divided into five groups: control, sham, and study groups (mesh-small [M-S], mesh-medium [M-M], mesh-large [M-L]). The M-S group used a mesh size of 0.2 × 0.2 cm, the M-M group a mesh size of 0.5 × 0.5 cm, and the M-L a mesh size of 0.7 × 1.0 cm. The sham group underwent vaginal dissection with no mesh implantation. The rats were sacrificed using isoflurane overdose on days 7 and 30. The mesh with the surrounding vaginal and bladder wall tissues were removed and processed for histochemical and western blot analysis.

RESULTS

There is a significant increase in IL-1 and TNF-α immunoreactivity in the M-M and M-L groups on day 7 when compared with the sham group with p values of 0.001 and < 0.001 respectively. M-L showed significantly higher immunoreactivity to TNF-α persisting until day 30. All study groups presented a significantly higher immunoreactivity to MMP-2 and NGF on day 7. However, reactivity to NGF does not persist to day 30 in all groups. Immunoreactivity to CD 31 on days 7 and 30 appears significantly greater in the M-M and M-L groups, with the reaction in the M-L group continuing until day 30.

CONCLUSION

Mesh size is directly proportional to the inflammatory reaction in the host tissue. The prolonged inflammatory process leads to delayed tissue remodeling and angiogenesis, which could delay mesh-tissue integration.

Recurrent urinary tract infection in women and overactive bladder - Is there a relationship?

Overactive bladder (OAB) in women has similar symptomatology with other common urologic diseases such as recurrent urinary tract infection (UTI). Recent evidence showed that chronic low-grade bacterial bladder colonization might exacerbate OAB symptoms and could be the etiology of recurrent UTI. The high prevalence of lower urinary tract dysfunction is associated with OAB. Women with urgency urinary incontinence refractory to antimuscarinic therapy had more bacteria and a more diverse urinary microbiome. The bacterial reside in the superficial urothelial cells to form intracellular bacterial community and outbreak when the host innate immunity is low. Women with recurrent UTI are found to have highly prevalent voiding dysfunction and detrusor overactivity. These functional abnormalities will further damage the urothelial barrier integrity and create vulnerable to uropathogen invasion. The defective urinary microbiota is less common in women with recurrent UTI, suggesting that the normal flora in the urine might inhibit uropathogen growth and invasion. The defective urothelial barrier function, deficient basal proliferation, and deficient maturation might be owing to chronic suburothelial inflammation, resulting in activation of sensory nerves (causing OAB) and failure elimination of intracellular bacterial communities (causing recurrent UTI). Precision diagnosis and multidisciplinary treatment of the underlying pathophysiology of OAB and recurrent UTI is necessary.

Urinary nerve growth factor: a biomarker for detrusor overactivity in children? A meta-analysis and trail sequential analysis

PURPOSE

Based on, previously, a systematic review, urinary nerve growth factor (NGF) has emerged as one potentially noninvasive biomarker for detrusor overactivity (DO) in adults. We performed this systematic review to explore if NGF is a biomarker for DO in children.

METHODS

A literature search was conducted in PubMed, Embase, Web of science, and Cochrane Library. Copies of all relevant articles were retrieved for quality assessment and data abstraction by two reviewers. Primary outcome was pooled standardized mean difference (SMD) for NGF/Cr (NGF normalized to urine creatinine) level between DO group and controls.

RESULTS

Three case-control studies published from 2012 to 2016 were included with 74 patients and 70 controls. Children with DO had a significant higher baseline urinary NGF/Cr level compared to controls (SMD = 2.48, 95%CI = 0.85-4.10, P < 0.01). After treatment, the level of NGF/Cr decreased significantly compared to baseline level at 6th month time points (SMD = 0.94, 95%CI = 0.03-1.86, P = 0.04). We calculated the required information size to 99 patients for comparison of urinary NGF/Cr level between DO and controls by trail sequential analysis (TSA).

CONCLUSION

Based on this systematic review, NGF/Cr may be a noninvasive biomarker for DO in children in the future. However, based on TSA, more original studies are needed to clarify the role of NGF/Cr in the biomarker effect.

Urinary Nerve Growth Factor as a Potential Biomarker of Treatment Outcomes in Overactive Bladder Patients

Purpose

The aim of this study was to investigate urinary nerve growth factor (NGF) as a biomarker of treatment efficacy and recurrence in overactive bladder (OAB) patients.

Methods

We enrolled 189 OAB subjects who visited our outpatient clinic from February 2010 to February 2015. All subjects with OAB received antimuscarinic treatment. A 3-day voiding diary and questionnaire were collected from each patient. Urinary levels of NGF were evaluated at baseline, the beginning of antimuscarinic treatment, and the end of antimuscarinic treatment. Urinary NGF was normalized to urine creatinine (Cr). Between-group comparisons of baseline characteristics were made using the Mann-Whitney U-test. Multivariate logistic regression analyses were used to predict responses to anticholinergic treatment and recurrence. The Wilcoxon signed-rank test with the Bonferroni correction was used for intragroup comparisons. A receiver operating characteristic curve was used to analyze the utility of this biomarker.

Results

Urinary levels of NGF/Cr tended to decrease in patients who responded to treatment (n=62), but this was not significant (P=0.260). Urinary NGF levels were higher at baseline in patients who did not experience recurrence than in those who did (P=0.047). In those who did not experience recurrence (n=29), urinary NGF/Cr decreased at the end of treatment compared to baseline, and this reduction was maintained at 12 weeks after the end of treatment (P<0.05).

Conclusions

Urinary NGF is a potential biomarker for predicting the outcome of antimuscarinic treatment in OAB patients. This may provide useful information when deciding to stop antimuscarinic treatment in responders.

PACAP/Receptor System in Urinary Bladder Dysfunction and Pelvic Pain Following Urinary Bladder Inflammation or Stress

Complex organization of CNS and PNS pathways is necessary for the coordinated and reciprocal functions of the urinary bladder, urethra and urethral sphincters. Injury, inflammation, psychogenic stress or diseases that affect these nerve pathways and target organs can produce lower urinary tract (LUT) dysfunction. Numerous neuropeptide/receptor systems are expressed in the neural pathways of the LUT and non-neural components of the LUT (e.g., urothelium) also express peptides. One such neuropeptide receptor system, pituitary adenylate cyclase-activating polypeptide (PACAP; Adcyap1) and its cognate receptor, PAC1 (Adcyap1r1), have tissue-specific distributions in the LUT. Mice with a genetic deletion of PACAP exhibit bladder dysfunction and altered somatic sensation. PACAP and associated receptors are expressed in the LUT and exhibit neuroplastic changes with neural injury, inflammation, and diseases of the LUT as well as psychogenic stress. Blockade of the PACAP/PAC1 receptor system reduces voiding frequency in preclinical animal models and transgenic mouse models that mirror some clinical symptoms of bladder dysfunction. A change in the balance of the expression and resulting function of the PACAP/receptor system in CNS and PNS bladder reflex pathways may underlie LUT dysfunction including symptoms of urinary urgency, increased voiding frequency, and visceral pain. The PACAP/receptor system in micturition pathways may represent a potential target for therapeutic intervention to reduce LUT dysfunction.

Urinary Metabolic Phenotyping of Women with Lower Urinary Tract Symptoms

Lower urinary tract symptoms (LUTS), including urinary incontinence, urgency and nocturia, affect approximately half of women worldwide. Current diagnostic methods for LUTS are invasive and costly, while available treatments are limited by side effects leading to poor patient compliance. In this study, we aimed to identify urine metabolic signatures associated with LUTS using proton nuclear magnetic resonance (¹H NMR) spectroscopy. A total of 214 urine samples were collected from women attending tertiary urogynecology clinics (cases; n = 176) and healthy control women attending general gynecology clinics (n = 36). Despite high variation in the urine metabolome across the cohort, associations between urine metabolic profiles and BMI, parity, overactive bladder syndrome, frequency, straining, and bladder storage were identified using KODAMA (knowledge discovery by accuracy maximization). Four distinct urinary metabotypes were identified, one of which was associated with increased urinary frequency and low BMI. Urine from these patients was characterized by increased levels of isoleucine and decreased levels of hippurate. Our study suggests that metabolic profiling of urine samples from LUTS patients offers the potential to identify differences in underlying etiology, which may permit stratification of patient populations and the design of more personalized treatment strategies.

Overactive bladder - 18 years - Part I

Abstract: Overactive bladder syndrome is one of the lower urinary tract dysfunctions with the highest number of scientific publications over the past two decades. This shows the growing interest in better understanding this syndrome, which gathers symptoms of urinary urgency and increased daytime and nighttime voiding frequency, with or without urinary incontinence and results in a negative impact on the quality of life of approximately one out of six individuals – including both genders and almost all age groups. The possibility of establishing the diagnosis just from clinical data made patients' access to specialized care easier. Physiotherapy resources have been incorporated into the urological daily practice. A number of more selective antimuscarinic drugs with consequent lower adverse event rates were released. Recently, a new class of oral drugs, beta-adrenergic agonists has become part of the armamentarium for Overactive Bladder. Botulinum toxin injections in the bladder and sacral neuromodulation are routine modalities of treatment for refractory cases. During the 1st Latin-American Consultation on Overactive Bladder, a comprehensive review of the literature related to the evolution of the concept, epidemiology, diagnosis, and management was conducted. This text corresponds to the first part of the review Overactive Bladder 18-years.

Nerve growth factor release from the urothelium increases via activation of bladder C-fiber in rats with cerebral infarction

AIMS

There are some reports that bladder C-fibers are partially involved in detrusor overactivity in patients with brain lesions. We investigated the contribution of bladder C-fiber to decreased bladder capacity in rats with cerebral infarction.

METHODS

Cerebral infarction was induced under halothane anesthesia by left middle cerebral artery occlusion with 4-0 nylon thread in female Sprague-Dawley rats. Intramural amounts of ATP and prostaglandin E₂ , in vivo and in vitro ATP, NGF, and prostaglandin E₂ release from the distended bladder urothelium, and changes in mRNA expressions of sensor molecules and receptors were monitored 6 h after the occlusion. Cystometry was performed in rats with or without resiniferatoxin pretreatment.

RESULTS

Overexpression of sensor molecule, transient receptor potential vanilloid-type channel 1, acid-sensing ion channel 2, purinergic receptors P2X₃ , and M₂ /M₃ muscarinic receptors was found in the bladder. These changes were accompanied by increases in ATP and NGF release from the urothelium. In contrast, when bladder C-fibers were desensitized by resiniferatoxin, no increase in NGF release from the urothelium was found either in vivo or in vitro. There was no difference in the percentage decrease in bladder capacity between cerebral infarction rats pretreated with resiniferatoxin and cerebral infarction rats without pretreatment.

CONCLUSIONS

Results indicate that expression of sensor molecules in the bladder is altered by distant infarction in the brain. ATP and NGF release from the urothelium also increased. NGF release was related to activation of bladder C-fibers. Bladder C-fibers might not contribute much to decreased bladder capacity caused by cerebral infarction.

Elevated level of nerve growth factor in the bladder pain syndrome/interstitial cystitis: a meta-analysis

Objectives

To elucidate the association between nerve growth factor (NGF) level and bladder pain syndrome/interstitial cystitis (BPS/IC) by conducting a meta-analysis.

Methods

We conducted a systematic literature search to identify original studies of NGF level in BPS/IC before November 2015. Eligible studies were retrieved via both computer searches and manual review of references. The summary difference estimates between controlled group and BPS/IC group were calculated based on the weighted mean difference (WMD) with its 95 % confidence interval (CI). Sensitivity and publication analyses were performed after the pooled analysis.

Results

Meta-analysis of 10 original studies involving 295 cases and 290 normal controls showed an increased level of urinary NGF in BPS/IC patients (z = 3.08, P = 0.002). The combined WMD was 36.39 (95 % CI 13.27–59.51). There was significant difference between controlled group and BPS/IC patients in the term of NGF/Cr level (WMD = 0.96, 95 % CI 0.58–1.35; z = 4.89, P < 0.01). There was no significant publication bias in the included studies (P for Begg’s test = 0.73, P for egger’s test = 0.13).

Conclusions

Our results demonstrated that there was an increased level of NGF in the BPS/IC patients.

Effects of CYP-Induced Cystitis on Growth Factors and Associated Receptor Expression in Micturition Pathways in Mice with Chronic Overexpression of NGF in Urothelium

We have determined if cyclophosphamide (CYP)-induced cystitis produces additional changes in growth factor/receptors expression in the urinary bladder (urothelium, detrusor) and lumbosacral (L6-S1) dorsal root ganglia (DRG) in a transgenic mouse model with chronic urothelial overexpression of NGF (NGF-OE). Functionally, NGF-OE mice treated with CYP exhibit significant increases in voiding frequency above that observed in control NGF-OE mice (no CYP). Quantitative PCR was used to determine NGF, BDNF, VEGF, and receptors (TrkA, TrkB, p75(NTR)) transcripts expression in tissues from NGF-OE and wild-type (WT) mice with CYP-induced cystitis of varying duration (4 h, 48 h, 8 days). In urothelium of control NGF-OE mice, NGF mRNA was significantly (p ≤ 0.001) increased. Urothelial expression of NGF mRNA in NGF-OE mice treated with CYP (4 h, 48 h, 8 days) was not further increased but maintained with all durations of CYP treatment evaluated. In contrast, CYP-induced cystitis (4 h, 48 h, 8 days) in NGF-OE mice demonstrated significant (p ≤ 0.05) regulation in BDNF, VEGF, TrkA, TrkB, and P75(NTR) mRNA in urothelium and detrusor smooth muscle. Similarly, CYP-induced cystitis (4 h, 48 h, 8 days) in NGF-OE mice resulted in significant (p ≤ 0.05), differential changes in transcript expression for NGF, BDNF, and receptors (TrkA, TrkB, p75(NTR)) in S1 DRG that was dependent on the duration-of CYP-induced cystitis. In general, NGF, BDNF, TrkA, and TrkB protein content in the urinary bladder increased in WT and NGF-OE mice with CYP-induced cystitis (4 h). Changes in NGF, TrkA and TrkB expression in the urinary bladder were significantly (p ≤ 0.05) greater in NGF-OE mice with CYP-induced cystitis (4 h) compared to WT mice with cystitis (4 h). However, the magnitude of change between WT and NGF-OE mice was only significantly (p ≤ 0.05) different for TrkB expression in urinary bladder of NGF-OE mice treated with CYP. These studies are consistent with target-derived NGF and other inflammatory mediators affecting neurochemical plasticity with potential contributions to reflex function of micturition pathways.

Lower Levels of Urinary Nerve Growth Factor Might Predict Recurrent Urinary Tract Infections in Women

PURPOSE

To investigate the changes in urinary nerve growth factor (uNGF) levels after acute urinary tract infection (UTI) and to assess the role of uNGF in predicting UTI recurrence in women.

METHODS

Women with uncomplicated, symptomatic UTIs were enrolled. Cephalexin 500 mg (every 6 hours) was administered for 7-14 days to treat acute UTIs. Subsequently, the patients were randomized to receive either sulfamethoxazole/trimethoprim 800 mg/160 mg daily at bedtime, or celecoxib 200 mg daily for 3 months and were monitored for up to 12 months. NGF levels in the urine were determined at baseline, 1, 4, and 12 weeks after the initiation of prophylactic therapy, and were compared between women with first-time UTIs and recurrent UTIs, sulfamethoxazole/trimethoprim and celecoxib-treated women, and no UTI recurrence and UTI recurrence that occurred during the follow-up period. Twenty women free of UTIs served as controls.

RESULTS

A total of 139 women with UTI and 20 controls were enrolled in the study, which included 50 women with a first-time UTI and 89 women with recurrent UTIs. Thirty-seven women completed the study. Women with recurrent UTIs (n=23) had a trend of lower uNGF levels than women with first-time UTIs (n=14). During follow-up, 9 women had UTI recurrence. The serial uNGF levels in women with UTI recurrence were significantly lower than those in women who did not have UTI recurrence during the follow-up period.

CONCLUSIONS

The lower levels of uNGF in women with recurrent UTI and the incidence of UTI recurrence during follow-up suggest that lower uNGF might reflect the defective innate immunity in women with recurrent UTI.

Not all neurogenic bladders are the same: a proposal for a new neurogenic bladder classification system

Neurogenic bladder (NGB) has long been defined as a clinical entity that describes a heterogeneous collection of syndromes. The common theme is a bladder disorder concomitant with a neurologic disorder. This definition does not give the clinician much information about the bladder disorder, nor how to treat it, or even what the natural history of the disorder is likely to be. It may be time for a new classification scheme to better define the bladder defect and prognosis, as well as inform treatment. We propose a classification system based on seven categories, each having a neurologic defect in a distinct anatomic location. This is termed SALE (Stratify by Anatomic Location and Etiology). In addition, the presence or absence of bowel dysfunction and autonomic dysreflexia will be reported. In the future, as more definite prognostic information can be gleaned from biomarkers, we anticipate adding urinary nerve growth factor (NGF) and urinary brain-derived neurotrophic factor (BDNF) levels to the definition. We expect the SALE system to efficiently describe a patient suffering from NGB and simultaneously inform the most appropriate treatment, follow-up regimen, and long-term prognosis.

Solifenacin and Tamsulosin Combination Therapy Decreases Urine Nerve Growth Factor/Creatinine Levels in Men

OBJECTIVE

To evaluate urinary nerve growth factor (NGF)/creatinine (Cr) levels from men with symptomatic lower urinary tract symptoms (LUTS) and measure the effect of combination therapy with solifenacin and tamsulosin.

MATERIALS AND METHODS

From January 2012 to February 2014, all male patients referred for evaluation and management of LUTS were screened for enrollment. In all subjects, urinary NGF and Cr levels were measured and normalized to the urinary Cr concentrations (NGF/Cr). Uroflow, postvoid residual, and symptom questionnaires were measured at baseline, 4 weeks, 8 weeks, and 12 weeks after starting combination therapy with solifenacin 5 mg and tamsulosin 0.4 mg. The primary endpoint was urinary NGF and NGF/Cr change from baseline compared with week 12.

RESULTS

Ten patients were recruited into the study. Peak urine flow at baseline 20.3 ± 2.5 ml/s and postvoid residual 45.3 ± 13.6 ml did not significantly change with 3 months of combination treatment 14.9 ± 1.8 ml/s and 58.5 ± 23.9 ml. However, urine NGF/Cr (pg/mg) levels were significantly reduced following treatment with levels of 39.7 ± 6.6 at baseline to 17.9 ± 5.1 at 3 months (P value <.05). The decrease in urine NGF/Cr levels correlated with significant decreases in patient reported outcomes.

CONCLUSION

Male patients with LUTS had decreased urinary NGF/Cr levels after treatment with combination solifenacin and tamsulosin in this novel pilot study. This corresponded with improvement in patient reported outcomes.

The association of urinary nerve growth factor levels with bladder outlet obstruction in women

OBJECTIVES

Nerve growth factor (NGF) has been proposed as a urinary biomarker and previously shown to be elevated in male patients with bladder outlet obstruction (BOO) and other lower urinary tract symptoms. No published studies have examined NGF as a potential urinary biomarker in women with BOO. The aims of this prospective study were to evaluate NGF levels in urine from women with anatomic BOO resulting from pelvic organ prolapse (POP) and/or previous incontinence surgery and to measure the effect associated with surgical or conservative management.

METHODS

From January to September 2012, all female patients referred for evaluation and management of BOO from POP or previous incontinence surgery were screened for enrollment. Inclusion criteria included elevated postvoid residual, valsalva voiding on urodynamics, or urinary peak flow (Qmax) of 12 mL/s or less. A control group of 10 asymptomatic age-matched female volunteers was also recruited. In all subjects, urinary NGF and creatinine (Cr) levels were measured and normalized to the urinary Cr concentrations (NGF/Cr). Urinary NGF levels were measured at 1 month and 3 months after either surgical correction or initiation of clean intermittent catheterization.

RESULTS

A total of 10 female patients with anatomic BOO (mean [SD] age of 66.2 [3.88] years) and 10 female control subjects (mean [SD] age of 62 [7] years) were recruited. Nine patients had POP. Six patients had undergone a previous anti-incontinence procedure. Five patients had both POP and undergone a previous anti-incontinence procedure. The urinary NGF/Cr levels in the study patients with BOO (mean [SE] 20.8 [4.31] pg/mg) were significantly higher (P = 0.0001) than the levels in the age-matched control group (5.6 [0.65] pg/mg). After treatment, the urinary NGF/Cr level significantly decreased to 6.50 (0.57) pg/mg (P = 0.01) CONCLUSIONS: In this study, female patients with anatomic BOO resulting from POP and/or previous incontinence surgery had significantly higher urinary NGF/Cr levels when compared with age-matched controls. After treatment, the urinary NGF/Cr levels significantly decreased.

A novel method for assessing bladder-related pain reveals the involvement of nerve growth factor in pain associated with cyclophosphamide-induced chronic cystitis in mice

BACKGROUND

Pain is a prominent feature of interstitial cystitis/painful bladder syndrome (IC/PBS), but the underlying mechanisms are not fully understood. There is a lack of well-characterized research tools, such as pain evaluation methods and experimental animal models, for investigating non-ulcerative cystitis. We developed a novel method for evaluating bladder pain in mice with cyclophosphamide (CYP)-induced cystitis.

METHODS

Cystitis was produced by a single intraperitoneal injection of CYP (300 mg/kg) or repeated injections of CYP (150 mg/kg once daily for 4 days). Blunt stimulation with a cotton probe was applied to the abdominal region, and the thresholds for withdrawal responses were measured quantitatively using an anaesthesiometer.

RESULTS

The single injection of CYP provoked acute cystitis with severe bladder inflammation in mice. In these mice, we could detect an increased sensitivity to blunt stimulation, which was abolished by intravesical lidocaine. The stimulation induced phosphorylation of extracellular signal-regulated kinases in bladder-projecting sensory neurons. Chronic treatment with CYP produced persistent pain responses to the blunt stimulus. Although there were few signs of bladder inflammation in these mice, the concentration of nerve growth factor (NGF) was elevated in bladder tissue, and NGF antiserum inhibited the hypersensitivity.

CONCLUSIONS

The blunt probe method is useful for evaluating bladder pain signalling in mice, and revealed the involvement of an NGF-sensitive pain pathway in chronic cystitis pain. This assessment method may be useful for studying the pathophysiology of bladder pain and for developing therapeutic strategies for non-ulcerative IC/PBS in patients.

Sacral nerve stimulation reduces elevated urinary nerve growth factor levels in women with symptomatic detrusor overactivity

OBJECTIVES

To investigate changes in urinary nerve growth factor (uNGF) in women with symptomatic detrusor overactivity (DO) following peripheral nerve evaluation (PNE) for sacral neuromodulation vs controls.

STUDY DESIGN

There were 23 subjects with overactive bladder symptoms and DO who failed management with anticholinergics and 22 controls consented to participate in this prospective pilot study. Urine specimens were collected from controls at baseline for evaluation of uNGF and creatinine. Subjects were evaluated at baseline and 5 days after a trial of sacral nerve stimulation referred to as a PNE. Each visit included urine collection for uNGF and, Incontinence Quality of Life Questionnaire, Urinary Distress Inventory Questionnaire, postvoid residual volume, and a 3-day voiding diary. uNGF levels were measured by enzyme-linked immunosorbent assay and expressed as uNGF pg/creatinine mg.

RESULTS

Subjects with DO had significantly higher baseline uNGF levels (corrected for creatinine) compared with controls (19.82 pg/mg vs 7.88 pg/mg, P < .002). Seventeen DO subjects underwent PNE and were evaluated at the end of the testing period. There was a significant improvement in quality of life scores for subjects after PNE compared with baseline (Urinary Distress Inventory Questionnaire: 7.0 vs 13.7, P < .001; Incontinence Quality of Life Questionnaire: 87.3 vs 52.8, P < .0001). Concordantly, uNGF levels significantly decreased from 17.23 pg/mg to 9.24 pg/mg (P < .02) after PNE.

CONCLUSION

uNGF levels decrease with symptomatic response in DO subjects undergoing PNE. DO subjects had significantly higher uNGF at baseline vs controls, and uNGF levels significantly decreased after only 5 days of sacral nerve stimulation. These findings support a larger study to validate the use of uNGF as an objective tool to assess therapeutic outcome in patients undergoing PNE for sacral neuromodulation.

Metabolomics insights into pathophysiological mechanisms of interstitial cystitis

Interstitial cystitis (IC), also known as painful bladder syndrome or bladder pain syndrome, is a chronic lower urinary tract syndrome characterized by pelvic pain, urinary urgency, and increased urinary frequency in the absence of bacterial infection or identifiable clinicopathology. IC can lead to long-term adverse effects on the patient's quality of life. Therefore, early diagnosis and better understanding of the mechanisms underlying IC are needed. Metabolomic studies of biofluids have become a powerful method for assessing disease mechanisms and biomarker discovery, which potentially address these important clinical needs. However, limited intensive metabolic profiles have been elucidated in IC. The article is a short review on metabolomic analyses that provide a unique fingerprint of IC with a focus on its use in determining a potential diagnostic biomarker associated with symptoms, a response predictor of therapy, and a prognostic marker.

Alteration of Urothelial Inflammation, Apoptosis, and Junction Protein in Patients with Various Bladder Conditions and Storage Bladder Symptoms Suggest Common Pathway Involved in Underlying Pathophysiology

OBJECTIVE

Lower urinary tract symptoms (LUTS) are common in various bladder disorders. This study investigated urothelial dysfunction and chronic inflammation in the urothelium in different types of lower urinary tract dysfunction (LUTD), which causes bladder storage symptoms.

METHODS

Bladder tissues were obtained from patients with LUTD including 17 with interstitial cystitis/bladder pain syndrome (IC/BPS), 15 with bladder outlet obstruction (BOO), 12 with spinal cord injury (SCI), 12 with recurrent urinary tract infection (UTI), 13 with ketamine related cystitis (KC) and 10 controls. The bladder specimens were investigated using immunofluorescence (IF) staining of the urothelial junction protein E-cadherin and the TUNEL assay for urothelial apoptosis. Mast cell activation was also measured by IF using tryptase for mucosal inflammation. Statistical analysis was performed using the Kruskal-Wallis and Wilcoxon rank-sum test and P-values less than 0.05 were considered significant.

RESULTS

Highly significant increases of mast cell infiltration were observed in patients with KC (7.8 ± 3.7), IC/BPS (4.6 ± 3.0), recurrent UTI (2.4 ± 1.2), SCI (3.7 ± 2.7), and BOO (5.1 ± 2.0) compared with controls (1.3 ± 1.2) (all p < 0.05). Statistically significant increases of apoptotic cells were observed in patients with KC (4.2 ± 1.5), IC/BPS (2.4 ± 1.7), SCI (2.4 ± 1.4), recurrent UTI (1.9 ± 2.4), and BOO (1.2 ± 1.1) compared with controls (0.08 ± 0.3) (all p < 0.05). Significantly decreased expression of E-cadherin in patients with IC/BPS (25.1 ± 16.3), KC (11.0 ± 11.3), and recurrent UTI (26.2 ± 5.0) was found compared to controls (42.4 ± 16.7) and patients with SCI (44.4 ± 18.8) or BOO (42.8 ± 14.3) (all P < 0.05).

CONCLUSION

Increased urothelial inflammation and urothelial cell apoptosis seem to share common pathophysiologies of various LUTDs that cause similar bladder symptoms.

What is the role for biomarkers for lower urinary tract disorders? ICI-RS 2013

AIMS

A biomarker is an entity that measures a normal or pathological process, or the response to an intervention. A biomarker must measure exclusively and be sufficiently sensitive to the process of interest. Alternatively, a biomarker may give clues regarding the underlying pathology of the condition and be a useful research or specialist tool. If a biomarker is to be of practical benefit then it must also be economical and practical to use. This article will consider chemical moieties as biomarkers, although in principle physical markers (e.g., bladder wall thickness) could also be defined as such.

RESULTS AND CONCLUSIONS

The validation of a biomarker for detrusor overactivity (DO) must appreciate the fact that the condition is likely to multifactorial and thus no single entity may be sufficiently selective and sensitive. However, more specific conditions, such as bladder pain associated with DO, may make the biomarker search easier. Several prospective agents including antiproliferative factor (APF) and epidermal growth factors (EGF) are discussed. Several urinary biomarkers, including neurotrophins (NGF, BDNF) and cytokines, and a serum marker, C-reactive protein, are considered as reaching the above criteria. All suffer from relatively poor lack of discrimination, as they all change in response to other, often inflammatory, conditions; BDNF may offer the highest expectations. Urinary ATP has also been proposed as a DO/OAB biomarker but requires further evaluation. Finally genetic markers offer potential to understand more about the pathophysiology of DO/OAB. The increasing availability of genome-wide association studies and micro-RNA assays offer genetic markers as a new generation of biomarkers. Neurourol. Urodynam. 33:602-605, 2014. © 2014 Wiley Periodicals, Inc.

Urinary ATP may be a dynamic biomarker of detrusor overactivity in women with overactive bladder syndrome

BACKGROUND

Nowadays, there is a considerable bulk of evidence showing that ATP has a prominent role in the regulation of human urinary bladder function and in the pathophysiology of detrusor overactivity. ATP mediates nonadrenergic-noncholinergic detrusor contractions in overactive bladders. In vitro studies have demonstrated that uroepithelial cells and cholinergic nerves from overactive human bladder samples (OAB) release more ATP than controls. Here, we compared the urinary ATP concentration in samples collected non-invasively from OAB women with detrusor overactivity and age-matched controls.

METHODS

Patients with neurologic diseases, history of malignancy, urinary tract infections or renal impairment (creatinine clearance <70 ml/min) were excluded. All patients completed a 3-day voiding diary, a 24 h urine collection and blood sampling to evaluate creatinine clearance. Urine samples collected during voluntary voids were immediately freeze-preserved for ATP determination by the luciferin-luciferase bioluminescence assay; for comparison purposes, samples were also tested for urinary nerve growth factor (NGF) by ELISA.

RESULTS

The urinary content of ATP, but not of NGF, normalized to patients' urine creatinine levels (ATP/Cr) or urinary volume (ATP.Vol) were significantly (P<0.05) higher in OAB women with detrusor overactivity (n = 34) than in healthy controls (n = 30). Significant differences between the two groups were still observed by boosting urinary ATP/Cr content after water intake, but these were not detected for NGF/Cr. In OAB patients, urinary ATP/Cr levels correlated inversely with mean voided volumes determined in a 3-day voiding diary.

CONCLUSION

A high area under the receiver operator characteristics (ROC) curve (0.741; 95% CI 0.62-0.86; P<0.001) is consistent with urinary ATP/Cr being a highly sensitive dynamic biomarker for assessing detrusor overactivity in women with OAB syndrome.

Increased urothelial cell apoptosis and chronic inflammation are associated with recurrent urinary tract infection in women

Objective

This study was designed to investigate whether increased urothelial cell apoptosis and chronic inflammation might contribute to recurrent urinary tract infection (UTI) in women.

Methods

The bladder biopsy specimens were collected from thirty women with recurrent UTI and ten controls. The bladder biopsies were performed at one to two months after UTI episode had been completely resolved and urine analysis and urine culture all showed negative. Immunofluorescence staining of the adhesive protein E-cadherin, mast cell and TUNEL were performed in all the bladder specimens. In addition, western blots were also performed to analyze the inflammatory proteins (phospho-p38, tryptase) and apoptotic protein (Bax) in the bladder mucosa specimens between patients with recurrent UTI and controls.

Results

Immunofluorescence staining showed significantly lower E-cadherin in the recurrent UTI bladder tissue compared with the controls (25.4±8.9 v 42.4±16.7, p<0.0001). The mast cell expression was significantly stronger in the recurrent UTI bladder tissue compared with the controls (2.5±1.8 v 1.3±1.2, p = 0.046). TUNEL staining revealed a significantly higher numbers of apoptotic cells in the recurrent UTI bladder tissue compared with the control bladder tissue (1.5±1.8 v 0.08±0.3, p<0.0001). Western blot analysis also showed that the expressions of tryptase and Bax increased in five recurrent UTI specimens compared with two normal control specimens.

Conclusion

Chronic inflammation, urothelial cell apoptosis and impairment of barrier function of urothelial cells might contribute to recurrent UTI in women.

Nerve growth factor (NGF): a potential urinary biomarker for overactive bladder syndrome (OAB)?

WHAT'S KNOWN ON THE SUBJECT? AND WHAT DOES THE STUDY ADD?: The search for a biomarker in overactive bladder syndrome (OAB) is an emerging field of interest, as bladder dysfunction is a common complaint that causes significant morbidity. A biomarker may give us insight as a diagnostic tool, and also inform us about how severe the condition is, how it may progress and how it may best be treated. The protein of interest here is nerve growth factor (NGF) and it has been shown to be a dynamic molecule in the bladder of patients with OAB. Urinary levels have been seen to rise in patients with OAB and fall in those who respond to treatment. However, there have also been many studies that examine this trend in numerous other conditions, e.g. interstitial cystitis, bladder outflow obstruction, renal stone disease and patients with neurological impairment after stroke. As a result the specificity of this as a potential urinary biomarker for OAB is questioned. This is a review of published studies, which discusses the pros and cons of NGF as a potential urinary biomarker. The evidence is examined and the studies are summarised together in a Table. Questions remain about the reliability, practicality and specificity of NGF as a biomarker for OAB. These questions need to be addressed by further studies that could clarify the points raised.

OBJECTIVE

To review the current literature on the use of urinary nerve growth factor (NGF) as a potential biomarker for overactive bladder syndrome (OAB).

METHOD

A comprehensive electronic literature search was conducted using the PubMed database to identify publications relating to urinary NGF.

RESULTS

There are a growing number of publications that have measured urinary NGF levels in different types of bladder dysfunction. These range from OAB, bladder pain syndrome, idiopathic and neurogenic detrusor overactivity, bladder oversensitivity and bladder outflow obstruction. Urinary NGF levels do appear to be raised in these pathological states when compared with healthy control samples. In patients with OAB, these raised urinary NGF levels appear to also reduce after successful treatment with antimuscarinics and botulinum toxin A, which indicates a potential use in monitoring responses to treatment. However, raised levels are not limited to OAB, which questions its specificity. Urinary NGF measurements are performed with an enzyme-linked immunosorbent assay using polyclonal antibodies to NGF. The technique requires standardisation, and the different antibodies to NGF require validating. Also a definition of what is the 'normal' range of NGF in urine is still required before it can be used as a diagnostic and prognostic tool.

CONCLUSIONS

Whilst the evidence for an increased urinary NGF in OAB appears convincing, many questions about its validity remain including: specificity, sensitivity, cost- and time-effectiveness. Many criteria for what constitutes a biomarker still need to be evaluated and met before this molecule can be considered for this role.

Changes in nerve growth factor level and symptom severity following antibiotic treatment for refractory overactive bladder

INTRODUCTION AND HYPOTHESIS

Overactive bladder (OAB) has a multifactorial aetiology, and for some women symptoms may be associated with chronic urothelial inflammation secondary to bacterial colonisation. One marker of such inflammation may be urinary nerve growth factor (NGF). We hypothesised that for women with OAB and urothelial inflammation, urinary NGF would be reduced following antibiotic therapy.

METHODS

Women with overactive bladder and urodynamic diagnosis of detrusor overactivity who were refractory to anticholinergics, and had histological evidence of urothelial inflammation were treated with a 6-week course of rotating antibiotics. Urinary NGF was measured by ELISA before and after treatment. Three-day bladder diaries, the Patients' Perception of Intensity of Urgency Scale, the King's Health Questionnaire and the Patients' Perception of Bladder Condition questionnaire were used to assess subjective and objective outcomes of therapy.

RESULTS

Thirty-nine women with refractory DO were recruited. The NGF levels decreased significantly after antibiotic therapy (Wilcoxon signed rank test; p = 0.015). There were significant improvements in daytime frequency, nocturia and urgency (p < 0.05), and 74 % of women reported improvement in perception of their bladder condition.

CONCLUSIONS

Urinary NGF is responsive to antibiotic therapy. Women with refractory overactive bladder and elevated NGF may benefit from antibiotic treatment.

Patent Highlights

A snapshot of recent key developments in the patent literature of relevance to the advancement of pharmaceutical and medical R&D

'Omics' approaches to understanding interstitial cystitis/painful bladder syndrome/bladder pain syndrome

Recent efforts in the generation of large genomics, transcriptomics, proteomics, metabolomics and other types of 'omics' data sets have provided an unprecedentedly detailed view of certain diseases, however to date most of this literature has been focused on malignancy and other lethal pathological conditions. Very little intensive work on global profiles has been performed to understand the molecular mechanism of interstitial cystitis/painful bladder syndrome/bladder pain syndrome (IC/PBS/BPS), a chronic lower urinary tract disorder characterized by pelvic pain, urinary urgency and frequency, which can lead to long lasting adverse effects on quality of life. A lack of understanding of molecular mechanism has been a challenge and dilemma for diagnosis and treatment, and has also led to a delay in basic and translational research focused on biomarker and drug discovery, clinical therapy, and preventive strategies against IC/PBS/BPS. This review describes the current state of 'omics' studies and available data sets relevant to IC/PBS/BPS, and presents opportunities for new research directed at understanding the pathogenesis of this complex condition.

Swimming: effects on stress urinary incontinence and the expression of nerve growth factor in rats following transabdominal urethrolysis

PURPOSE

Stress urinary incontinence (SUI) commonly occurs in women, and it has an enormous impact on quality of life. Surgery, drugs, and exercise have been recommended for the treatment of this disease. Among these, exercise is known to be effective for the relief of symptoms of SUI; however, the efficacy and underlying mechanisms of the effect of exercise on SUI are poorly understood. We investigated the effect of swimming the symptom of SUI in relation to the expression of nerve growth factor (NGF) in rats.

METHODS

Transabdominal urethrolysis was used to induce SUI, in Sprague-Dawley rats. The experimental groups were divided into the following three groups: sham-operation group, transabdominal urethrolysis-induced group, and transabdominal urethrolysis-induced and swimming group. The rats in the swimming group were forced to swim for 30 minutes once daily starting 2 weeks after SUI induction and continuing for 4 weeks. For this study, determination of abdominal leak point pressure and immunohistochemistry for NGF in the urethra and in the neuronal voiding centers (medial preoptic nucleus [MPA], ventrolateral periaqueductal gray [vlPAG], pontine micturition center [PMC], and spinal cord [L4-L5]) were performed.

RESULTS

Transabdominal urethrolysis significantly reduced the abdominal leak point pressure, thereby contributing to the induction of SUI. Abdominal leak point pressure, however, was significantly improved by swimming. The expression of NGF in the urethra and in the neuronal voiding centers (MPA, vlPAG, PMC, and L4-L5) relating to micturition was enhanced by the induction of SUI. Swimming, however, significantly suppressed SUI-induced NGF expression.

CONCLUSIONS

Swimming alleviated symptoms of transabdominal urethrolysis-induced SUI, as assessed by an increase in abdominal leak point pressure. The underlying mechanisms of these effects of swimming might be ascribed to the inhibitory effect of swimming on NGF expression.