Mechanisms Underlying Overactive Bladder and Interstitial Cystitis/Painful Bladder Syndrome

Association between overactive bladder and depression in American adults: A cross-sectional study from NHANES 2005-2018

BACKGROUND AND AIM

Overactive bladder (OAB) and depression are both common disorders and there is research suggesting an association between the two, but there is a lack of studies with large samples. The aim of this study is to investigate the association between OAB and depressive symptoms.

METHODS

We used data from the National Health and Nutrition Examination Survey (NHANES) database for the period 2005 to 2018. OAB was characterized by the Overactive Bladder Symptom Score (OABSS, score > 3) and depression was diagnosed by the Patient Health Questionnaire (PHQ-9, score ≥ 10). There were three models employed in our analysis: (1) Crude model was unadjusted; (2) Model 1 was adjusted for age, sex, race/ethnicity, educational level, and marital status; (3) Model 2 was adjusted for factors in Model 1 plus the remained potential covariates. We used survey-weighted logistic regression models to assess the association between OAB and depression. Subsequently, subgroup analyses and smoothed curve analyses were used to evaluate the reliability of the findings.

RESULTS

Finally, a total of 6612 participants were included in our study, consisting of 1005 participants with diagnosis of OAB and 5607 participants without diagnosis of OAB. After adjusting for all covariates, there was a significant positive association between OAB and depression (OR: 2.89, 95 % CI: 1.91, 4.37). The severity of OAB was also positively associated with depression. Compared to participants without OAB, the fully adjusted ORs for depression were 2.76 (95 % CI: 1.64, 4.65) for those with mild OAB, 3.79 (95 % CI: 1.68, 8.55) for those with moderate OAB, and 5.21 (95 % CI: 1.39, 19.53) for those with severe OAB.

CONCLUSIONS

This study revealed a strong association between OAB and depression and a progressive increase in the risk of depression as the severity of OAB (mild, moderate, and severe) increased. Therefore, it is important for clinicians to recognize the assessment of OAB symptoms in patients who are at risk for or have developed depressive symptoms, as well as the mental health of patients with OAB.

Mental health and lower urinary tract symptoms: Results from the NHANES and Mendelian randomization study

BACKGROUND

The clinical observations suggest a correlation between lower urinary tract symptoms (LUTSs) and mental health problems. Nonetheless, establishing a direct causal relationship between them remains challenging.

METHODS

We initially conducted a cross-sectional study using 2005-2018 the National Health and Nutrition Examination Survey (NHANES) data. Multivariable-adjusted logistic regression was the primary statistical approach. Additionally, we employed Mendelian randomization (MR) to reducing confounding and reverse causation. Genetic instruments were obtained from publicly available genome-wide association study (GWAS) databases. Inverse Variance Weighted was the primary statistical method.

RESULTS

The cross-sectional study involved 29,439 participants. Individuals with mental health problems had a higher risk of urinary incontinence (OR:4.38; 95%CI:3.32-5.76; P < 0.01) and overactive bladder (OR:2.31; 95%CI:2.02-2.63; P < 0.01). MR analysis then indicated a potential causal relationship between mental health problems and LUTSs. Depression symptoms was linked with urinary tract infection (UTI) (OR:1.005; 95%CI:1.003-1.008; PFDR < 0.01). Anxiety symptoms was related to the occurrence of UTI (OR:1.024; 95%CI:1.011-1.037; PFDR < 0.01) and bladder calcified/ contracted/ overactive (OR:1.017; 95%CI:1.007-1.027; PFDR < 0.01). The personality trait of neuroticism was related to the occurrence of cystitis (OR:1.072; 95%CI:1.022-1.125; PFDR = 0.02), extravasation of urine and difficulties with micturition (OR:1.001; 95%CI:1.001-1.002; PFDR < 0.01), and urinary frequency and incontinence (OR: 1.001; 95%CI:1.000-1.001; PFDR < 0.01).

CONCLUSIONS

Our study provides various evidence for the correlation between mental health and LUTSs, emphasizing the significance of adopting a holistic approach to LUTSs management that incorporates both physical and psychological factors.

Machine Learning-Based Classification of Transcriptome Signatures of Non-Ulcerative Bladder Pain Syndrome

Lower urinary tract dysfunction (LUTD) presents a global health challenge with symptoms impacting a substantial percentage of the population. The absence of reliable biomarkers complicates the accurate classification of LUTD subtypes with shared symptoms such as non-ulcerative Bladder Pain Syndrome (BPS) and overactive bladder caused by bladder outlet obstruction with Detrusor Overactivity (DO). This study introduces a machine learning (ML)-based approach for the identification of mRNA signatures specific to non-ulcerative BPS. Using next-generation sequencing (NGS) transcriptome data from bladder biopsies of patients with BPS, benign prostatic obstruction with DO, and controls, our statistical approach successfully identified 13 candidate genes capable of discerning BPS from control and DO patients. This set was validated using Quantitative Polymerase Chain Reaction (QPCR) in a larger patient cohort. To confirm our findings, we applied both supervised and unsupervised ML approaches to the QPCR dataset. A three-mRNA signature TPPP3, FAT1, and NCALD, emerged as a robust classifier for non-ulcerative BPS. The ML-based framework used to define BPS classifiers establishes a solid foundation for comprehending the gene expression changes in the bladder during BPS and serves as a valuable resource and methodology for advancing signature identification in other fields. The proposed ML pipeline demonstrates its efficacy in handling challenges associated with limited sample sizes, offering a promising avenue for applications in similar domains.

Machine Learning-based Classification of transcriptome Signatures of non-ulcerative Bladder Pain Syndrome

Lower urinary tract dysfunction (LUTD) presents a global health challenge with symptoms impacting a substantial percentage of the population. The absence of reliable biomarkers complicates the accurate classification of LUTD subtypes with shared symptoms such as non-ulcerative Bladder Pain Syndrome (BPS) and overactive bladder caused by bladder outlet obstruction with Detrusor Overactivity (DO). This study introduces a machine learning (ML)-based approach for the identification of mRNA signatures specific to non-ulcerative BPS. Using next-generation sequencing (NGS) transcriptome data from bladder biopsies of patients with BPS, benign prostatic obstruction with DO and controls, our statistical approach successfully identified 13 candidate genes capable of discerning BPS from control and DO patients. This set was subsequently validated using Quantitative Polymerase Chain Reaction (QPCR) in a larger patient cohort. To confirm our findings, we applied both supervised and unsupervised ML approaches to the QPCR dataset. Notably, a three-mRNA signature TPPP3, FAT1, and NCALD, emerged as a robust classifier, effectively distinguishing patients with non-ulcerative BPS from controls and patients with DO. This signature was universally selected by both supervised and unsupervised approaches. The ML-based framework used to define BPS classifiers not only establishes a solid foundation for comprehending the specific gene expression changes in the bladder of the patients with BPS but also serves as a valuable resource and methodology for advancing signature identification in other fields. The proposed ML pipeline demonstrates its efficacy in handling challenges associated with limited sample sizes, offering a promising avenue for applications in similar domains.

BCG induced lower urinary tract symptoms during treatment for NMIBC-Mechanisms and management strategies

Non-muscle invasive bladder cancer (NMIBC) accounts for ~70-75% of total bladder cancer tumors and requires effective early intervention to avert progression. The cornerstone of high-risk NMIBC treatment involves trans-urethral resection of the tumor followed by intravesical Bacillus Calmette-Guerin (BCG) immunotherapy. However, BCG therapy is commonly accompanied by significant lower urinary tract symptoms (LUTS) including urinary urgency, urinary frequency, dysuria, and pelvic pain which can undermine treatment adherence and clinical outcomes. Despite this burden, the mechanisms underlying the development of BCG-induced LUTS have yet to be characterized. This review provides a unique perspective on the mechanisms thought to be responsible for the development of BCG-induced LUTS by focussing on the sensory nerves responsible for bladder sensory transduction. This review focuses on how the physiological response to BCG, including inflammation, urothelial permeability, and direct interactions between BCG and sensory nerves could drive bladder afferent sensitization leading to the development of LUTS. Additionally, this review provides an up-to-date summary of the latest clinical data exploring interventions to relieve BCG-induced LUTS, including therapeutic targeting of bladder contractions, inflammation, increased bladder permeability, and direct inhibition of bladder sensory signaling. Addressing the clinical burden of BCG-induced LUTS holds significant potential to enhance patient quality of life, treatment compliance, and overall outcomes in NMIBC management. However, the lack of knowledge on the pathophysiological mechanisms that drive BCG-induced LUTS has limited the development of novel and efficacious therapeutic options. Further research is urgently required to unravel the mechanisms that drive BCG-induced LUTS.

Uroprotective and pain-relieving effect of dietary supplementation with micronized palmitoyl-glucosamine and hesperidin in a chronic model of cyclophosphamide-induced cystitis

Introduction

Feline idiopathic cystitis is a common, chronic-relapsing disorder of the lower urinary tract. In addition to environmental modification/enrichment, long-term and safe treatment targeting specific pathophysiological changes may be of help. In this context, effective dietary interventions hold clinical promise. Palmitoyl-glucosamine (PGA) and hesperidin (HSP) are safe and authorized feed ingredients for animal nutrition under European regulations.

Methods

The current study aimed to investigate whether a 3:1 mixture of micronized PGA and HSP could represent a novel mechanism-oriented approach to chronic cystitis management. A newly validated rat model of cyclophosphamide (CYP)-induced chronic cystitis was used (40 mg/kg, three intraperitoneal injections every 3rd day). Animals were randomized to orally receive either vehicle or PGA-HSP at a low (72 + 24 mg/kg) or high (doubled) dose for 13 days, starting 3 days before the chronic CYP protocol, with mesna (2-mercaptoethane-sulfonate) being used as a reference drug.

Results

Higher PGA-HSP dose was effective at relieving chronic visceral pain, as measured by mechanical allodynia test (von Frey test). The severity of cystitis was also significantly improved, as shown by the reduced sonographic thickening of the bladder wall, as well as the decrease in edema, bleeding and bladder to body weight ratio compared to the vehicle treated group. A significant decrease of MPO activity, MDA level and fibrosis at Masson's trichrome staining was also observed in animals administered PGA-HSP in comparison to vehicle treated ones. The CYP-induced increase in bladder mRNA expression of pro-inflammatory cytokines was also significantly counteracted by the study mixture. Moreover, CYP-induced bladder mast cell accumulation and releasability were significantly decreased by PGA-HSP (even at the low dose), as determined by metachromatic staining, chymase and tryptase immunostaining as well as enzyme-linked immunosorbent assay for histamine and 5-hydoxytriptamine.

Discussion

PGA-HSP is able to block CYP-induced decrease of tight junction proteins, claudin-1 and occludin, thus preserving the urothelial bladder function. Finally, neuroinflammatory changes were investigated, showing that dietary supplementation with PGA-HSP prevented the activation of neurons and non-neuronal cells (i.e., microglia, astrocytes and mast cells) at the spinal level, and counteracted CYP-induced increase of spinal mRNA encoding for pro-inflammatory cytokines. Altogether, the present findings confirm the uroprotective and pain-relieving effect of PGA-HSP and pave the way to potential and relevant clinical applications of the study supplement in feline idiopathic cystitis.

The prevalence of probable overactive bladder and associated risk factors among medical students in Jordan: a cross-sectional study

BACKGROUND

To discuss the impact of overactive bladder (OAB) on medical students. overactive bladder. is a chronic condition that causes sudden and intense urges to urinate, which can have significant physical and psychological effects on patients' lives. The prevalence of OAB among medical students is relatively high, with some studies reporting rates as high as 35.4%. This research aims to shed light on the prevalence rates and risk factors associated with OAB among medical students in Jordan.

METHODS

A cross-sectional study was conducted using an online self-reported questionnaire as the study tool. The questionnaire collected the sociodemographic, health, and academic characteristics of medical students, as well as the new 7-item OABSS score.

RESULTS

Out of the total sample of medical students surveyed (n = 525), 44.5% reported experiencing symptoms of OAB. Furthermore, the analysis also revealed that there was a significant difference in the prevalence of OAB between the ages of medical students. In addition, the study also found that there was a significant association between OAB symptoms and basic years, positive history of diagnostic UTI, positive history of recent trauma, high stress, and taking certain medications.

CONCLUSIONS

The study highlights the need for further research in this area and emphasizes the possible implications of OAB for medical students, including the need for additional support and resources to manage the condition.

Financial strain across 25 years and women's bladder health: a life course perspective

BACKGROUND

A small number of cross-sectional studies have found that financial insecurity-a social determinant of health-is associated with lower urinary tract symptoms.

OBJECTIVE

This study aimed to examine (1) whether women in the Coronary Artery Risk Development in Young Adult Study with higher levels of financial strain, assessed at 7 time points across 25 years beginning in 1985-1986, were more likely to report lower urinary tract symptoms and impact after the 2010-2011 financial strain assessment and (2) whether healthcare access and comorbidities mediated potential associations.

STUDY DESIGN

This prospective cohort study recruited Black and White participants aged 18 to 30 years at baseline (1985-1986) from the populations of 4 US cities. The analytical sample was composed of women with complete data for analyses involving financial strain trajectories across 7 assessments (n=841) and mediation tests of data collected at 4 assessments (n=886). The outcome variable was previously developed through a cluster analysis of urinary incontinence severity, urinary incontinence impact, other lower urinary tract symptoms severity, and their impact in 2012-2013, which yielded 4 lower urinary tract symptoms and impact cluster categories: women with no symptom or very mild symptoms and no impact vs women with mild, moderate, or severe symptoms and impact. Financial strain was defined as finding it "very hard," "hard," or "somewhat hard" (vs "not very hard") to pay for the very basics, such as food, heating, and medical care. Using proportional odds logistic regression, cluster categories were regressed on the financial strain trajectory group, adjusting for age, race, education, and parity. For mediation analyses, separate financial strain variables (difficulty paying for the very basics, such as food and heating, and difficulty paying for medical care) were created by combining 1995-1996 and 2000-2001 values. Two healthcare access variables (difficulty receiving care and underutilization of care) and a single comorbidity index (smoking, physical inactivity, body mass index, hypertension, diabetes mellitus, and depressive symptoms) were created by combining 2005-2006 and 2010-2011 values. Regression analyses and structural equation modeling were used to test whether healthcare access and comorbidities mediated associations between financial strain and lower urinary tract symptoms and impact cluster categories.

RESULTS

In comparison to women who were consistently not financially strained, women who were consistently strained (odds ratio, 2.10; 95% confidence interval, 1.13-3.91), shifted into being strained (odds ratio, 2.00; 95% confidence interval, 1.29-3.10), or experienced >1 shift in strain (odds ratio, 1.99; 95% confidence interval, 1.46-2.71) had roughly twice the odds of reporting greater lower urinary tract symptoms and impact. Underutilization of healthcare and comorbidities mediated the association between difficulty paying for medical care and lower urinary tract symptoms and impact. In the structural equation model, difficulty paying for medical care and underutilization of care were associated (β=.31; P<.01), as was underutilization of care and greater lower urinary tract symptoms and impact (β=.09; P<.01). Moreover, difficulty paying for medical care and the comorbidity index were associated (β=.34; P<.01), as was the comorbidity index and greater lower urinary tract symptoms and impact (β=.24; P<.01). Collectively, these mediation pathways eliminated a direct association between difficulty paying for medical care and lower urinary tract symptoms and impact.

CONCLUSION

Underutilization of healthcare and comorbidities explained an association between financial strain (difficulty paying for medical care) and lower urinary tract symptoms and impact. Research is needed to confirm the findings and examine other mechanisms that may further explain the association. Accumulated evidence may inform future policies and practices.

Discrimination and bladder health among women in the CARDIA cohort study: Life course and intersectionality perspectives

OBJECTIVE

This study examines whether discriminatory experiences are associated with lower urinary tract symptoms (LUTS) and their impact among 972 women in the Coronary Artery Risk Development in Young Adults (CARDIA) cohort study, which recruited participants from 4 cities in the United States.

METHOD

Exposure to discrimination was assessed 3 times (1992-93, 2000-01, 2010-11) and averaged across assessments. Participants separately reported whether they experienced discrimination on the basis of their gender, race or color, and socioeconomic position or social class. For each social identity, discrimination was assessed in 6-7 settings (e.g., when getting a job, medical care, or housing). At different time points, women who reported discriminatory experiences for a given social identity were asked how frequently the discrimination occurred and how stressful experience(s) were. Following the 2010-11 assessment, data on LUTS and their impact were collected. Women were classified into bladder health versus mild, moderate, or severe symptoms/impact clusters.

RESULTS

More Black than White women reported discriminatory experiences across all social identities and most settings. Perceived stress of discriminatory experiences did not differ between Black and White women. In analyses stratified by race and social identity, White women reported LUTS/impact with discriminatory experiences in more settings, more frequent discriminatory experiences across settings, and each additional social identity for which discrimination was experienced. Black women reported LUTS/impact with more frequent discriminatory experiences across settings. For Black women, greater perceived stress of both gender and race discrimination were associated with LUTS/impact. For White women, only greater perceived stress of race discrimination was associated with LUTS/impact.

CONCLUSIONS

This is one of the first studies to examine discrimination in relation to LUTS/impact. Additional research is needed to better understand differences in how discriminatory experiences based on potentially intersecting identities may be related to bladder health among women.

Psychosocial Factors Associated with Lower Urinary Tract Symptoms One Year Postpartum

Pregnancy carries substantial risk for developing lower urinary tract symptoms (LUTSs), with potential lifelong impacts on bladder health. Little is known about modifiable psychosocial factors that may influence the risk of postpartum LUTSs. We examined associations between depressive symptoms, perceived stress, and postpartum LUTSs, and the moderating effects of perceived social support, using data from a cohort study of Expect With Me group prenatal care (n = 462). One year postpartum, 40.3% participants reported one or more LUTS. The most frequent LUTS was daytime frequency (22.3%), followed by urinary incontinence (19.5%), urgency (18.0%), nocturia (15.6%), and bladder pain (6.9%). Higher odds of any LUTS were associated with greater depressive symptoms (adjusted odds ratio (AOR) 1.08, 95% confidence interval (CI) 1.04-1.11) and perceived stress (AOR 1.12, 95% CI 1.04-1.19). Higher perceived social support was associated with lower odds of any LUTS (AOR 0.94, 95% CI 0.88-0.99). Perceived social support mitigated the adverse effects of depressive symptoms (interaction AOR 0.99, 95% CI 0.98-0.99) and perceived stress (interaction AOR 0.97, 95% CI 0.95-0.99) on experiencing any LUTS. Greater depressive symptoms and perceived stress may increase the likelihood of experiencing LUTSs after childbirth. Efforts to promote bladder health among postpartum patients should consider psychological factors and social support.

The expression and distribution of TACAN in human and rat bladders

OBJECTIVES

A lot of ion channels participate in the regulation of bladder function. TACAN, a new mechanosensitive ion channel, was first discovered in 2020. TACAN has been found to be expressed in many tissues, such as the dorsal root ganglia (DRG) and adipose tissue. However, it is unclear whether or not TACAN is expressed in the bladder. In this work, we decided to study the expression and distribution of TACAN in human and rat bladders. Meanwhile, the expression of TACAN in the rat model of interstitial cystitis/bladder pain syndrome (IC/BPS) was studied.

METHODS

Human bladder tissues were obtained from female patients. Cyclophosphamide (CYP) was used to build the rat model of IC/BPS. Real-time polymerase chain reaction, agarose gel electrophoresis, and western blotting were used to assess the expression of TACAN in human and rat bladders. Immunohistochemistry and immunofluorescence were used to observe the distribution of TACAN in human and rat bladders. Hematoxylin-eosin stain, withdrawal threshold, and micturition interval were used to evaluate animal models.

RESULTS

The results of agarose gel electrophoresis and western blotting suggested that TACAN was expressed in human and rat bladders. Immunohistochemical results suggested that TACAN showed positive immunoreaction in the urothelial and detrusor layers. The immunofluorescence results indicated that TACAN was co-stained with UPKIII, α-SMA, and PGP9.5. The IC/BPS model was successfully established with CYP. The mRNA and protein expression of TACAN was upregulated in the CYP-induced rat model of IC/BPS.

CONCLUSIONS

TACAN was found in human and rat bladders. TACAN was mainly distributed in the urothelial and detrusor layers and bladder nerves. The expression of TACAN was upregulated in the CYP-induced rat model of IC/BPS. This new discovery will provide a theoretical basis for future research on the function of TACAN in the bladder and a potential therapeutic target for IC/BPS.

How does the lower urinary tract contribute to bladder sensation? ICI-RS 2023

AIM

Bladder sensation is critical for coordinating voluntary micturition to maintain healthy bladder function. Sensations are initiated by the activation of sensory afferents that innervate throughout the bladder wall. However, the physiological complexity that underlies the initiation of bladder sensory signaling in health and disease remains poorly understood. This review summarises the latest knowledge of the mechanisms underlying the generation of bladder sensation and identifies key areas for future research.

METHODS

Experts in bladder sensory signaling reviewed the literature on how the lower urinary tract contributes to bladder sensation and identified key research areas for discussion at the 10th International Consultation on Incontinence-Research Society.

RESULTS

The importance of bladder sensory signals in maintaining healthy bladder function is well established. However, better therapeutic management of bladder disorders with exaggerated bladder sensation, including overactive bladder syndrome (OAB) and interstitial cystitis/bladder pain syndrome (IC/BPS) is limited by a lack of knowledge in a number of key research areas including; the contribution of different nerves (pudendal, pelvic, hypogastric) to filling sensations in health and disease; the relative contribution of stretch sensitive (muscular) and stretch-insensitive (mucosal) afferents to bladder sensation in health and disease; the direct and indirect contributions of the muscularis mucosae to bladder contraction and sensation; and the impact of manipulating urothelial release factors on bladder sensation.

CONCLUSION

Disturbances in bladder sensory signaling can have severe consequences for bladder sensation and function including the development of OAB and IC/BPS. Advancing therapeutic treatments for OAB and IC/BPS requires a deeper understanding of the mechanisms underlying the generation of bladder sensation, and key areas for future research have been identified.

Intrathecal umbilical cord mesenchymal stem cells injection alleviates neuroinflammation and oxidative stress in the cyclophosphamide-induced interstitial cystitis rats through the Sirt1/Nrf2/HO-1 pathway

AIMS

Neuroinflammation in the spinal dorsal horn (SDH) region plays an important role in the pathogenesis of interstitial cystitis (IC)/bladder pain syndrome (BPS). Oxidative stress is an important etiological factor for inflammatory diseases. This study aimed to investigate the therapeutic effects of umbilical cord mesenchymal stem cells UMSCs on neuroinflammation and oxidative stress in IC and the underlying mechanisms.

MATERIALS AND METHODS

Rats were intraperitoneally injected with cyclophosphamide (50 mg/kg bodyweight) to establish the IC animal model. Additionally, rats were intrathecally injected with a Sirt1-specific agonist (SRT1720; 8 μg/rat) or inhibitor (EX527; 8 μg/rat). Furthermore, rats were intrathecally injected with human UMSCs (hUMSCS; 8 × 105 cells/rat). Rat behavior was examined using the mechanical allodynia test, novel object recognition test, sucrose preference test, and urodynamics analysis. Neuroinflammation and oxidative stress the SDH region were examined using western blotting, immunofluorescence, enzyme-linked immunosorbent assay, and commercial kits.

KEY FINDINGS

The Sirt1/Nrf2/HO-1 pathway was downregulated in IC rats. Sirt1 activation and inhibition differentially affected the behavior of IC rats. hUMSCs effectively mitigated the upregulation of oxidative stress, proinflammatory cytokines, and glial activation in the SDH region. Additionally, hUMSCs suppressed mechanical allodynia, dysregulated urodynamics, memory deficits, and depressive-like behavior in IC rats. hUMSCs exerted therapeutic effects through the Sirt1/Nrf2/HO-1 pathway.

SIGNIFICANCE

intrathecal hUMSCs injection alleviated behavioral deficits of IC rats by mitigating neuroinflammation and oxidative stress through the Sirt1/Nrf2/HO-1 pathway and can be potentially an effective therapeutic strategy for IC.

Animal models of interstitial cystitis/bladder pain syndrome

Interstitial Cystitis/Bladder Pain Syndrome (IC/BPS) is a chronic disorder characterized by pelvic and/or bladder pain, along with lower urinary tract symptoms that have a significant impact on an individual's quality of life. The diverse range of symptoms and underlying causes in IC/BPS patients pose a significant challenge for effective disease management and the development of new and effective treatments. To facilitate the development of innovative therapies for IC/BPS, numerous preclinical animal models have been developed, each focusing on distinct pathophysiological components such as localized urothelial permeability or inflammation, psychological stress, autoimmunity, and central sensitization. However, since the precise etiopathophysiology of IC/BPS remains undefined, these animal models have primarily aimed to replicate the key clinical symptoms of bladder hypersensitivity and pain to enhance the translatability of potential therapeutics. Several animal models have now been characterized to mimic the major symptoms of IC/BPS, and significant progress has been made in refining these models to induce chronic symptomatology that more closely resembles the IC/BPS phenotype. Nevertheless, it's important to note that no single model can fully replicate all aspects of the human disease. When selecting an appropriate model for preclinical therapeutic evaluation, consideration must be given to the specific pathology believed to underlie the development of IC/BPS symptoms in a particular patient group, as well as the type and severity of the model, its duration, and the proposed intervention's mechanism of action. Therefore, it is likely that different models will continue to be necessary for preclinical drug development, depending on the unique etiology of IC/BPS being investigated.

Activation of the adenosine A1 receptor in the lumbosacral spinal cord improves bladder overactivity in rats with cystitis induced by cyclophosphamide

PURPOSE

To investigate the effect of intrathecal administration of CCPA, an adenosine A1 receptor agonist, on voiding function in rats with cystitis induced by cyclophosphamide (CYP).

METHODS

Thirty 8-week-old Sprague Dawley rats were randomly divided into a control group (n = 15) and a cystitis group (n = 15). Cystitis was induced by a single intraperitoneal injection of CYP (200 mg/kg, dissolved in physiological saline) in rats. Control rats were injected intraperitoneally with physiological saline. The PE10 catheter reached the level of L6-S1 spinal cord through L3-4 intervertebral space for intrathecal injection. Forty-eight hours after intraperitoneal injection, urodynamic tests were conducted to observe the effect of intrathecal administration of 10% dimethylsulfoxide (vehicle) and 1 nmol CCPA on micturition parameters, including basal pressure (BP), threshold pressure (TP), maximal voiding pressure (MVP), intercontraction interval (ICI), voided volume (VV), residual volume (RV), bladder capacity (BC), and voiding efficiency (VE). Histological changes of the bladder of cystitis rats were studied through hematoxylin-eosin staining (HE staining). Moreover, Western blot and immunofluorescence were used to study the expression of adenosine A1 receptor in the L6-S1 dorsal spinal cord in both groups of rats.

RESULTS

HE staining revealed submucosal hemorrhage, edema, and inflammatory cell infiltration in the bladder wall of cystitis rats. The urodynamic test showed significant increase in BP, TP, MVP and RV in cystitis rats, while ICI, VV, BC and VE decreased significantly, indicating bladder overactivity. CCPA inhibited the micturition reflex in both control and cystitis rats, and significantly increased TP, ICI, VV, BC, and VE, but had no significant effect on BP, MVP and RV. Western blot and immunofluorescence showed that there was no significant difference in the expression of adenosine A1 receptor in the L6-S1 dorsal spinal cord between the control and cystitis rats.

CONCLUSION

The findings of this study suggest that intrathecal administration of the adenosine A1 receptor agonist CCPA alleviates CYP-induced bladder overactivity. Furthermore, our results indicate that the adenosine A1 receptor in the lumbosacral spinal cord may be a promising target for treatment of bladder overactivity.

Current optimal pharmacologic therapies for overactive bladder

INTRODUCTION

Overactive bladder (OAB) is a common syndrome in adults. Current pharmacologic treatment includes antimuscarinic agents and β-3 adrenoceptor agonists. For non-responders to oral medication, intravesical injection of botulinum toxin A (BoNT-A) is an effective option. However, these treatments have potential adverse events and should be cautiously selected for appropriate patients. This review presents the recently published results of clinical trials and studies for patients with OAB and the underlying pathophysiology of OAB. Appropriate medical therapy based on pathophysiology of OAB is also presented.

AREAS COVERED

Literature search from Pubmed from 2001 to 2023 including clinical background, pharmacology, and clinical studies for OAB medications.

EXPERT OPINION

Treatment of OAB syndrome with any antimuscarinic or β-3 adrenoceptor agonist is feasible as a first-line approach. For patients with suboptimal therapeutic effect to full-dose antimuscarinics or mirabegron, combination with both drugs can improve efficacy. Intravesical BoNT-A 100-U injection provides therapeutic effects for refractory OAB. Patients who are refractory to initial pharmacotherapies should be investigated for the underlying pathophysiology; then an appropriate medication can be added, such as an α1-blocker or anti-inflammatory agents. Patient education about behavioral modification and therapies should always be provided with oral medication or BoNT-A injection for OAB patients.

Overactive bladder syndrome symptoms in youth with abdominal pain-associated disorders of gut-brain interaction

The purpose of the current study was to assess the frequency of overactive bladder syndrome (OBS) symptoms and their relationship to gastrointestinal symptoms in youth with abdominal pain-associated disorders of gut-brain interaction (AP-DGBI). This is a retrospective study of 226 youth diagnosed with an AP-DGBI. As part of standard care, all patients completed a symptom questionnaire regarding gastrointestinal and non-gastrointestinal symptoms including increased urinary frequency, nighttime urination, and urinary urgency. Overall, 54% of patients reported at least one OBS symptom. Increased frequency of urination was reported by 19%, urinary urgency by 34%, and nighttime urination by 36%. Increased frequency of urination and urinary urgency were associated with a change in stool form, a change in stool frequency, and in those fulfilling criteria for IBS. Increased frequency of urination was reported more frequently in those reporting predominantly loose stools (33% vs. 12%). Urinary symptoms are common in youth with AP-DGBI. Increased urinary frequency and urinary urgency are specifically associated with IBS, with increased urinary frequency being primarily associated with diarrhea predominant IBS. Further studies are needed to determine the impact of OBS on AP-DGBI severity and quality of life, and whether they impact DGBI treatment.

Trajectories of depressive symptoms over 20 years and subsequent lower urinary tract symptoms and impact among women

OBJECTIVE

The aim of the study is to examine the association between depressive symptoms and subsequent lower urinary tract symptoms (LUTS) and impact (a composite outcome) among women (N = 1,119) from the Coronary Artery Risk Development in Young Adults study.

METHODS

The Center for Epidemiologic Studies-Depression Scale (CES-D) was administered in 1990-1991 and every 5 years through 2010-2011. In 2012-2013, LUTS and impact data were collected for the first time. Accumulation of risk was examined in the following three ways: (1) mean CES-D score across 20 years (5 observations); (2) depressive symptom trajectory group, determined by group-based trajectory modeling; and (3) intercepts and slopes obtained from women's individual CES-D score trajectories through two-stage mixed effects modeling. For each approach, ordinal logistic regression analyses examined odds of having "greater LUTS/impact" for each unit change in a depressive symptom variable.

RESULTS

(1) With each one-unit increase in mean CES-D score over the 20-year period, women were 9% more likely to report greater LUTS/impact (odds ratio [OR] = 1.09, 95% CI = 1.07-1.11). (2) In comparison with women with consistently low depressive symptoms, women with consistently threshold depression or consistently high depressive symptoms were twice (OR = 2.07, 95% CI = 1.59-2.69) and over five times (OR = 5.55, 95% CI = 3.07-10.06) as likely, respectively, to report greater LUTS/impact. (3) Women's individual symptom intercept and slope interacted. Increases in depressive symptoms across 20 years (greater slopes) were associated with greater LUTS/impact when women's initial CES-D score (intercept) was in the moderate-to-high range relative to the sample.

CONCLUSIONS

Depressive symptoms over 20 years, examined with different degrees of nuance, were consistently associated with subsequently measured LUTS and impact.

Interpersonal Stressors and Resources for Support: Associations with Lower Urinary Tract Symptoms and Impact Among Women

Background: This study utilizes Coronary Artery Risk Development in Young Adults (CARDIA) data to examine whether women's perceived emotional support and interpersonal stressors are associated with lower urinary tract symptoms (LUTS) and their impact on quality of life. Materials and Methods: Emotional support was assessed at baseline/year 0 (1985-86), year 2 (1987-88), year 15 (2000-01), and year 20 (2005-06); interpersonal stressors were assessed at years 15 and 20. In 2012-13, LUTS and impact were assessed. LUTS/impact category (a composite variable ranging from bladder health to mild, moderate, and severe LUTS/impact) was regressed on trajectory groups of emotional support from years 0 to 20. Separately, LUTS/impact was regressed on mean emotional support and interpersonal stressors across years 15-20. Analyses were adjusted for age, race, education, and parity (n = 1104). Results: In comparison to women whose support trajectory from years 0 to 20 was consistently high, women whose support decreased from high to low had over twice the odds (odds ratio [OR] = 2.72; 95% confidence interval [CI] = 1.76-4.20) of being classified into a more burdensome LUTS/impact category. Mean support and interpersonal stressors across years 15-20 were independently associated with lower odds (OR = 0.59; 95% CI = 0.44-0.77) and greater odds (OR = 1.52; 95% CI = 1.19-1.94), respectively, of being classified into a more burdensome LUTS/impact category. Conclusions: In the CARDIA cohort, quality of women's interpersonal relationships, assessed between 1985-86 and 2005-06, was associated with LUTS/impact assessed in 2012-13. Additional research collecting LUTS/impact data at multiple time points is needed to test potential bidirectional associations of emotional support and interpersonal stressors with LUTS/impact, as well as potential mechanisms of association.

Urinary Tract Infections: The Current Scenario and Future Prospects

Urinary tract infections (UTIs) are among the most common bacterial infections worldwide, occurring in both community and healthcare settings. Although the clinical symptoms of UTIs are heterogeneous and range from uncomplicated (uUTIs) to complicated (cUTIs), most UTIs are usually treated empirically. Bacteria are the main causative agents of these infections, although more rarely, other microorganisms, such as fungi and some viruses, have been reported to be responsible for UTIs. Uropathogenic Escherichia coli (UPEC) is the most common causative agent for both uUTIs and cUTIs, followed by other pathogenic microorganisms, such as Klebsiella pneumoniae, Proteus mirabilis, Enterococcus faecalis, and Staphylococcus spp. In addition, the incidence of UTIs caused by multidrug resistance (MDR) is increasing, resulting in a significant increase in the spread of antibiotic resistance and the economic burden of these infections. Here, we discuss the various factors associated with UTIs, including the mechanisms of pathogenicity related to the bacteria that cause UTIs and the emergence of increasing resistance in UTI pathogens.

Supraphysiologic Vaginal Estrogen Therapy in Aged Mice Mitigates Age-Associated Bladder Inflammatory Response to Urinary Tract Infections

IMPORTANCE

Bladder diseases characterized by chronic inflammation are highly prevalent in older women, as are recurrent urinary tract infections (rUTIs). Recurrent urinary tract infections lead to chronic inflammation of the bladder mucosa and cause lower urinary tract symptoms that persist even after the infection is cleared. Vaginal estrogen therapy (VET) has long been used for the treatment of rUTIs; however, its mechanism of action remains unclear.

OBJECTIVES

The objective of this study was to examine the mechanism(s) by which VET affects bladder inflammation and response to rUTIs.

STUDY DESIGN

Here, we induced surgical menopause in aged (18 months old) mice followed by VET. Mice were then infected with uropathogenic Escherichia coli , and course of infection was investigated. Inflammatory cytokine response was assessed before and during infection using enzyme-linked immunosorbent assay. RNA sequencing analysis was used to compare the inflammatory status of the young versus aged bladder and principal changes confirmed via quantitative reverse transcriptase-polymerase chain reaction to determine the effects of VET on bladder inflammation. Impact on age-associated bladder tertiary lymphoid tissue formation was evaluated histologically.

RESULTS

In the ovariectomized aged model, VET not only mitigated uterine atrophy but was also associated with reduced rUTIs, number of bacterial reservoirs, dampened immune response, and promotion of terminal differentiation of urothelial cells. Bladder tertiary lymphoid tissue lesions were also reduced with VET, with an associated decrease in signals important for bladder tertiary lymphoid tissue formation. Finally, we determined that VET reverses age-associated upregulation of inflammatory genes and pathways.

CONCLUSIONS

Our data suggest that VET is effective by reducing age-associated hyperinflammatory conditions in bladder mucosa and in enhancing the host response to infection.

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.

Role of circadian rhythms and melatonin in bladder function in heath and diseases

The circadian system modulates all visceral organ physiological processes including urine storage and voiding. The "master clock" of the circadian system lies within suprachiasmatic nucleus of the hypothalamus while "peripheral clocks" are found in most peripheral tissue and organs, including the urinary bladder. Disruptions of circadian rhythms can cause organ malfunction and disorder or exacerbate pre-existing ones. It has been suggested that nocturia, which develops mostly in the elderly, could be a circadian-related disorder of the bladder. In the bladder, many types of gap junctions and ion channels in the detrusor, urothelium and sensory nerves are likely under strict local peripheral circadian control. The pineal hormone, melatonin, is a circadian rhythm synchroniser capable of controlling a variety of physiological processes in the body. Melatonin predominantly acts via the melatonin 1 and melatonin 2 G-protein coupled receptors expressed in the central nervous system, and many peripheral organs and tissues. Melatonin could be beneficial in the treatment of nocturia and other common bladder disorders. The ameliorating action of melatonin on bladder function is likely due to multiple mechanisms which include central effects on voiding and peripheral effects on the detrusor and bladder afferents. More studies are warranted to determine the precise mechanisms of circadian rhythm coordination of the bladder function and melatonin influences on the bladder in health and diseases.

Sensory Receptor, Inflammatory, and Apoptotic Protein Expression in the Bladder Urothelium of Patients with Different Subtypes of Interstitial Cystitis/Bladder Pain Syndrome

The aim of this study was to investigate the expression levels of sensory receptors, inflammatory proteins, and pro-apoptotic proteins in the urothelium of non-Hunner's interstitial cystitis (NHIC) bladders of patients with different clinical and cystoscopic phenotypes. The urothelia from the bladders of 52 NHIC patients were harvested. The expression of sensory receptors, including TRPV1, TRPV4, TRPA1, H1-receptors, and sigma-1 receptors; the inflammatory proteins p38 and tryptase; and the pro-apoptotic proteins, such as caspase-3, BAD, and BAX in the urothelium, were investigated using immunohistochemistry and Western blotting. We compared the expression levels of these proteins in NHIC subtypes according to IC symptom scores, visual analog scores of bladder pain, maximal bladder capacity, glomerulation grades, and combined maximal bladder capacity and glomerulations after cystoscopic hydrodistention. The expression levels of TRPV1, TRPV4, sigma-1, P38, tryptase, caspase-3, and BAD were significantly increased in the urothelium of IC/BPS patients compared with the expression levels in the controls. TRPV1 was significantly associated with IC symptom severity. However, no significant differences in sensory receptor expression in the IC/BPS bladders with different bladder conditions were detected. Inflammatory and pro-apoptotic protein expression levels in the urothelium were similar among the IC/BPS subgroups. This study concluded that IC/BPS patients with frequency and bladder pain complaints have higher levels of urothelial sensory receptors, and inflammatory and pro-apoptotic proteins. The expression levels of these sensory receptors, inflammatory proteins, and pro-apoptotic proteins are not significantly different among IC/BPS bladders with different conditions.

Effects of aging on urinary tract epithelial homeostasis and immunity

A global increase in older individuals creates an increasing demand to understand numerous healthcare challenges related to aging. This population is subject to changes in tissue physiology and the immune response network. Older individuals are particularly susceptible to infectious diseases, with one of the most common being urinary tract infections (UTIs). Postmenopausal and older women have the highest risk of recurrent UTIs (rUTIs); however, why rUTIs become more frequent after menopause and during old age is incompletely understood. This increased susceptibility and severity among older individuals may involve functional changes to the immune system with age. Aging also has substantial effects on the epithelium and the immune system that led to impaired protection against pathogens, yet heightened and prolonged inflammation. How the immune system and its responses to infection changes within the bladder mucosa during aging has largely remained poorly understood. In this review, we highlight our understanding of bladder innate and adaptive immunity and the impact of aging and hormones and hormone therapy on bladder epithelial homeostasis and immunity. In particular, we elaborate on how the cellular and molecular immune landscape within the bladder can be altered during aging as aged mice develop bladder tertiary lymphoid tissues (bTLT), which are absent in young mice leading to profound age-associated change to the immune landscape in bladders that might drive the significant increase in UTI susceptibility. Knowledge of host factors that prevent or promote infection can lead to targeted treatment and prevention regimens. This review also identifies unique host factors to consider in the older, female host for improving rUTI treatment and prevention by dissecting the age-associated alteration of the bladder mucosal immune system.

Microbiota-Pain Association; Recent Discoveries and Research Progress

The relationship between gut microbiota and pain, such as visceral pain, headaches (migraine), itching, prosthetic joint infection (PJI), chronic abdominal pain (CAP), joint pain, etc., has received increasing attention. Several parts of the evidence suggest that microbiota is one of the most important pain modulators and they can regulate pain in the central and peripheral nervous systems. Any alteration in microbiota by diet or antibiotics mediation may characterize a novel therapeutic strategy for pain management. The present study includes the most up-to-date and influential scientific findings on the association of microbiota with pain, despite the fact that the underlying mechanism is not identified in most cases. According to recent research, identifying the molecular mechanisms of the microbiota-pain pathway can have a unique perspective in treating many diseases, even though there is a long way to reach the ideal point. This study will stress the influence of microbiota on the common diseases that can stimulate the pain with a focus on underlying mechanisms.

Predictors of Male Sexual Dysfunction in Urologic Chronic Pelvic Pain Syndrome (UCPPS), Other Chronic Pain Syndromes, and Healthy Controls in the Multidisciplinary Approach to the Study of Chronic Pelvic Pain (MAPP) Research Network

BACKGROUND

Sexual dysfunction (SD), including erectile (ED) and ejaculatory dysfunction, is associated with diminished quality of life (QoL) in men with UCPPS (chronic prostatitis/chronic pelvic pain syndrome (CP/CPPS) and/or interstitial cystitis/bladder pain syndrome (IC/BPS)).

AIM

We sought to compare SD among male patients with UCPPS, other chronic pain conditions (positive controls, PC), and healthy controls (HC) without chronic pain, and to evaluate the association of comorbidities, psychosocial factors, and urologic factors of SD in all 3 groups.

METHODS

Baseline data from male UCPPS participants, PC (irritable bowel syndrome, chronic fatigue syndrome, fibromyalgia) and HC enrolled in the Multidisciplinary Approach to the Study of Chronic Pelvic Pain (MAPP) Research Network Epidemiology and Phenotyping Study were included in the analysis. Sexual function was assessed using the International Index of Erectile Function-Erectile Function Domain (IIEFEF) and Ejaculatory Function Scale (EFS). Male ED was defined as a composite IIEF-EF score <21. Higher EFS score indicated worse sexual dysfunction; no threshold to define SD was identified for the EFS. Multivariable logistic and linear regression was used to investigate associations of comorbidities, psychosocial factors, and urologic factors with ED and ejaculatory, respectively.

OUTCOMES

Comorbidities, genital pain, and psychosocial factors are associated with SD across the study population and male patients with UCPPS had a high prevalence of ED and greater ejaculatory dysfunction.

RESULTS

There were 191 males with UCPPS; 44 PC; and 182 HC. Males with UCPPS had worse SD compared to PC and HC including lower mean IIEF-EF scores, greater degree of ejaculatory dysfunction, and lower quality of sexual relationships. Among all 3 cohorts, depression, stress, and pain were associated with ED in univariable and multivariable analysis, as was diabetes mellitus. Pain in the genitalia, severity of urinary symptoms, depression, stress, and history of childhood sexual trauma were associated with ejaculatory dysfunction in univariable and multivariable analysis.

CLINICAL IMPLICATIONS

A multidisciplinary approach that addresses the identified risk factors for SD may improve overall QoL in males with UCPPS.

STRENGTHS AND LIMITATIONS

Our study is strengthened by its use of validated, patient-reported questionnaires and inclusion of healthy and positive controls. Our understanding of the role of IC in this study is limited because only 1 patient in the study had IC/BPS as a sole diagnosis.

CONCLUSIONS

When compared to healthy controls and patients with other chronic pain conditions, males with UCPPS experience higher degrees of SD, including erectile and ejaculatory dysfunction. Loh-Doyle JC, Stephens-Shields AJ, Rolston R, et al. Predictors of Male Sexual Dysfunction in Urologic Chronic Pelvic Pain Syndrome (UCPPS), Other Chronic Pain Syndromes, and Healthy Controls in the Multidisciplinary Approach to the Study of Chronic Pelvic Pain (MAPP) Research Network. J Sex Med 2022;19:1804-1812.

The T-type calcium channel Ca V 3.2 regulates bladder afferent responses to mechanical stimuli

ABSTRACT

The bladder wall is innervated by a complex network of afferent nerves that detect bladder stretch during filling. Sensory signals, generated in response to distension, are relayed to the spinal cord and brain to evoke physiological and painful sensations and regulate urine storage and voiding. Hyperexcitability of these sensory pathways is a key component in the development of chronic bladder hypersensitivity disorders including interstitial cystitis/bladder pain syndrome and overactive bladder syndrome. Despite this, the full array of ion channels that regulate bladder afferent responses to mechanical stimuli have yet to be determined. Here, we investigated the role of low-voltage-activated T-type calcium (Ca V 3) channels in regulating bladder afferent responses to distension. Using single-cell reverse-transcription polymerase chain reaction and immunofluorescence, we revealed ubiquitous expression of Ca V 3.2, but not Ca V 3.1 or Ca V 3.3, in individual bladder-innervating dorsal root ganglia neurons. Pharmacological inhibition of Ca V 3.2 with TTA-A2 and ABT-639, selective blockers of T-type calcium channels, dose-dependently attenuated ex-vivo bladder afferent responses to distension in the absence of changes to muscle compliance. Further evaluation revealed that Ca V 3.2 blockers significantly inhibited both low- and high-threshold afferents, decreasing peak responses to distension, and delayed activation thresholds, thereby attenuating bladder afferent responses to both physiological and noxious distension. Nocifensive visceromotor responses to noxious bladder distension in vivo were also significantly reduced by inhibition of Ca V 3 with TTA-A2. Together, these data provide evidence of a major role for Ca V 3.2 in regulating bladder afferent responses to bladder distension and nociceptive signalling to the spinal cord.

Comprehensive transcriptome profiling of urothelial cells following TNFα stimulation in an in vitro interstitial cystitis/bladder pain syndrome model

Urothelial cells of the urinary bladder play a critical role in the development and progression of interstitial cystitis/bladder pain syndrome (IC/BPS), a chronic and debilitating inflammatory disease. Given the lack of data on the exact phenotype and function of urothelial cells in an inflammatory setting (as in IC/BPS), we performed the first in-depth characterization of these cells using RNA sequencing, qPCR, ELISA, Western blot, and immunofluorescence. After TNFα stimulation, urothelial cells in the in vitro model of IC/BPS showed marked upregulation of several proinflammatory mediators, such as SAA, C3, IFNGR1, IL1α, IL1β, IL8, IL23A, IL32, CXCL1, CXCL5, CXCL10, CXCL11, TNFAIPR, TNFRSF1B, and BIRC3, involved in processes and pathways of innate immunity, including granulocyte migration and chemotaxis, inflammatory response, and complement activation, as well as TLR-, NOD-like receptor- and NFkB-signaling pathways, suggesting their active role in shaping the local immune response of the bladder. Our study demonstrates that the TNFα-stimulated urothelial cells recapitulate key observations found in the bladders of patients with IC/BPS, underpinning their utility as a suitable in vitro model for understanding IC/BPS mechanisms and confirming the role of TNFα signaling as an important component of the associated pathology. The present study also identifies novel upregulated gene targets of TNFα in urothelial cells, including genes encoding the acute phase protein SAA, complement component C3, and the cytokine receptor IFNGR1, which could be exploited as therapeutic targets of IC/BPS. Altogether, our study provides a reference database of the phenotype of urothelial cells in an inflammatory environment that will not only increase our knowledge of their role in IC/BPS, but also advance our understanding of how urothelial cells shape tissue immunity in the bladder.

Transient receptor potential vanilloid type 4 (TRPV4) in urinary bladder structure and function

Bladder pain syndrome (BPS)/interstitial cystitis (IC) is a urologic, chronic pelvic pain syndrome characterized by pelvic pain, pressure, or discomfort with urinary symptoms. Symptom exacerbation (flare) is common with multiple, perceived triggers including stress. Multiple transient receptor potential (TRP) channels (TRPA1, TRPV1, TRPV4) expressed in the bladder have specific tissue distributions in the lower urinary tract (LUT) and are implicated in bladder disorders including overactive bladder (OAB) and BPS/IC. TRPV4 channels are strong candidates for mechanosensors in the urinary bladder and TRPV4 antagonists are promising therapeutic agents for OAB. In this perspective piece, we address the current knowledge of TRPV4 distribution and function in the LUT and its plasticity with injury or disease with an emphasis on BPS/IC. We review our studies that extend the knowledge of TRPV4 in urinary bladder function by focusing on (i) TRPV4 involvement in voiding dysfunction, pelvic pain, and non-voiding bladder contractions in NGF-OE mice; (ii) distention-induced luminal ATP release mechanisms and (iii) involvement of TRPV4 and vesicular release mechanisms. Finally, we review our lamina propria studies in postnatal rat studies that demonstrate: (i) the predominance of the TRPV4+ and PDGFRα+ lamina propria cellular network in early postnatal rats; (ii) the ability of exogenous mediators (i.e., ATP, TRPV4 agonist) to activate and increase the number of lamina propria cells exhibiting active Ca2+ events; and (iii) the ability of ATP and TRPV4 agonist to increase the rate of integrated Ca2+ activity corresponding to coupled lamina propria network events and the formation of propagating wavefronts.

Urinary Tract Infection in Overactive Bladder: An Update on Pathophysiological Mechanisms

Overactive bladder (OAB) is a clinical syndrome defined by urinary urgency, increased daytime urinary frequency and/or nocturia, with or without urinary incontinence, that affects approximately 11% of the western population. OAB is accepted as an idiopathic disorder, and is charactersied clinically in the absence of other organic diseases, including urinary tract infection. Despite this, a growing body of research provides evidence that a significant proportion of OAB patients have active bladder infection. This review discusses the key findings of recent laboratory and clinical studies, providing insight into the relationship between urinary tract infection, bladder inflammation, and the pathophysiology of OAB. We summarise an array of clinical studies that find OAB patients are significantly more likely than control patients to have pathogenic bacteria in their urine and increased bladder inflammation. This review reveals the complex nature of OAB, and highlights key laboratory studies that have begun to unravel how urinary tract infection and bladder inflammation can induce urinary urgency and urinary frequency. The evidence presented in this review supports the concept that urinary tract infection may be an underappreciated contributor to the pathophysiology of some OAB patients.

TGR5 agonists induce peripheral and central hypersensitivity to bladder distension

The mechanisms underlying chronic bladder conditions such as interstitial cystitis/bladder pain syndrome (IC/BPS) and overactive bladder syndrome (OAB) are incompletely understood. However, targeting specific receptors mediating neuronal sensitivity to specific stimuli is an emerging treatment strategy. Recently, irritant-sensing receptors including the bile acid receptor TGR5, have been identified within the viscera and are thought to play a key role in neuronal hypersensitivity. Here, in mice, we identify mRNA expression of TGR5 (Gpbar1) in all layers of the bladder as well as in the lumbosacral dorsal root ganglia (DRG) and in isolated bladder-innervating DRG neurons. In bladder-innervating DRG neurons Gpbar1 mRNA was 100% co-expressed with Trpv1 and 30% co-expressed with Trpa1. In vitro live-cell calcium imaging of bladder-innervating DRG neurons showed direct activation of a sub-population of bladder-innervating DRG neurons with the synthetic TGR5 agonist CCDC, which was diminished in Trpv1-/- but not Trpa1-/- DRG neurons. CCDC also activated a small percentage of non-neuronal cells. Using an ex vivo mouse bladder afferent recording preparation we show intravesical application of endogenous (5α-pregnan-3β-ol-20-one sulphate, Pg5α) and synthetic (CCDC) TGR5 agonists enhanced afferent mechanosensitivity to bladder distension. Correspondingly, in vivo intravesical administration of CCDC increased the number of spinal dorsal horn neurons that were activated by bladder distension. The enhanced mechanosensitivity induced by CCDC ex vivo and in vivo was absent using Gpbar1-/- mice. Together, these results indicate a role for the TGR5 receptor in mediating bladder afferent hypersensitivity to distension and thus may be important to the symptoms associated with IC/BPS and OAB.

Lectins as Biomarkers of IC/BPS Disease: A Comparative Study of Glycosylation Patterns in Human Pathologic Urothelium and IC/BPS Experimental Models

Pathophysiology of interstitial cystitis/bladder pain syndrome (IC/BPS) remains poorly understood, as well as its effective diagnosis and therapy. Studying changes in tissue glycosylation patterns under pathological conditions is a promising way of discovering novel biomarkers and therapeutic targets. The glycobiology of IC/BPS is largely understudied, therefore we compared glycosylation patterns of normal human urothelium with the urothelium of IC/BPS patients using a selection of 10 plant-based lectins with different monosaccharide preferences. We also compared lectin binding to human urothelium with the two most cited experimental models of IC/BPS, specifically, TNFα-treated human urothelial cell line RT4 and cyclophosphamide-induced chronic cystitis in C57BL6/J mice. Furthermore, binding of four of the selected lectins (ConA, DSL, Jacalin and WGA) was evaluated qualitatively by means of fluorescence microscopy, and quantitatively by fluorescence intensity (F.I.) measurements. Our results reveal a significant reduction in F.I. of Jacalin, as well as a prominent change in the WGA labeling pattern in the urothelium of IC/BPS patients, suggesting their potential use as promising additional biomarkers for histopathological diagnosis of IC/BPS. We have also shown that urothelial glycosylation patterns between selected experimental models and patients with IC/BPS are similar enough to offer an adequate platform for preclinical study of IC/BPS glycobiology.

Activation of CXCL13/CXCR5 axis aggravates experimental autoimmune cystitis and interstitial cystitis/bladder pain syndrome

The abnormal CXCL13/CXCR5 axis is involved in many inflammatory diseases and its selective inhibitor, TAK-799 has exhibited strong anti-inflammatory potency. The sequencing of clinical specimens from interstitial cystitis/bladder pain syndrome (IC/BPS) has shown that CXCL13 and CXCR5 are highly expressed, but the role of CXCL13/CXCR5 axis in IC/BPS has not been rarely reported. Therefore, in this study, we analyzed the GSE11783 sequencing data of IC/BPS patients and investigate the role and mechanism of CXCL13/CXCR5 axis and TAK-779 in the mouse model of experimental autoimmune cystitis (EAC). We verified that CXCL13 and CXCR5 were significantly up-regulated in EAC model. EAC mice exhibited increased bladder inflammatory factors (IL-6, TNF-α, IL-1β), apoptosis-related proteins (Bax, Caspase-3, Caspase-8), frequency of voiding. Using TAK779 to block CXCL13/CXCR5 axis significantly attenuated these inflammatory damages and efficiently improved bladder function (significant reduction in micturition frequency, significant prolongation of inter-contraction interval). Further investigation showed that inhibiton of JNK and NF-kappaB activation, the bioinformatics analysis-indicated downstream signaling of CXCL13/CXCR5 axis, is responsible for the protective effect of TAK779. Taken together, we demonstrate that activation of the CXCL13/CXCR5 axis is involved in the pathophysiology of IC/BPS and EAC. Blocking CXCL13/CXCR5 axis activation by TAK-779 reduces bladder inflammation and improves bladder function in EAC mice.

Extracellular vesicles derived from mesenchymal stem cells alleviate neuroinflammation and mechanical allodynia in interstitial cystitis rats by inhibiting NLRP3 inflammasome activation

Background

Neuroinflammation in spinal dorsal horn (SDH) plays an important role in the pathogenesis of interstitial cystitis/bladder pain syndrome (IC/BPS). Mesenchymal stem cell-derived extracellular vesicles (MSC-EVs) exert potent anti-inflammatory activities in the treatment of various diseases. This study aimed to determine the therapeutic effects of MSC-EVs on IC and furtherly investigate the potential mechanism to attenuate neuroinflammation.

Methods

Female IC rat model was established by intraperitoneal injection of cyclophosphamide (50 mg/kg, every 3 days for 3 doses). Inhibition of NLRP3 inflammasome was performed by intraperitoneal injection of MCC950 (10 mg/kg). MSC-EVs were isolated from the culture supernatants of human umbilical cord derived MSCs using ultracentrifugation, and then injected intrathecally into IC rats (20 μg in 10 μl PBS, every other day for 3 doses). Suprapubic mechanical allodynia was assessed using up-down method with von Frey filaments, and micturition frequency was examined by urodynamics. The expression of NLRP3 inflammasome components (NLRP3 and Caspase-1), glial cell markers (IBA-1 and GFAP), proinflammatory cytokines (TNF-α, IL-1β, IL-6 and IL-18) and TLR4/NF-κB signal pathway (TLR4, p65 NK-κB and phospho-p65 NK-κB) in L6–S1 SDH was measured by Western blot analysis. The cellular localization of NLRP3 in SDH was detected using immunofluorescence co-staining.

Results

NLRP3 inflammasome was activated in neurons in SDH of IC rats. NLRP3 inflammasome activation contributed to activation of glial cells and process of spinal neuroinflammation in IC rats, and was related to suprapubic mechanical allodynia and frequent micturition. Intrathecal injection of MSC-EVs alleviated suprapubic mechanical allodynia and frequent micturition in IC rats, restrained activation of glial cells and attenuated neuroinflammation in SDH. In addition, MSC-EV treatment significantly inhibited activation of both NLRP3 inflammasomes and TLR4/NF-κB signal pathway.

Conclusions

NLRP3 inflammasome activation is involved in the neuroinflammation of IC. Intrathecal injection of MSC-EVs alleviates neuroinflammation and mechanical allodynia in IC by inhibiting the activation of NLRP3 inflammasome, and TLR4/NF-κB signal pathway may be the potential regulatory target.

Multidisciplinary treatment for functional urological disorders with psychosomatic comorbidity in a tertiary pelvic care center-A retrospective cohort study

Background

Functional urological disorders are highly prevalent, frequently interrelated, and characterized by a chronic course and considerable treatment resistance. From our point of view, poor treatment outcomes are often attributable to underlying but undetected mental disorders.

Objective

To investigate the effect of integrated outpatient care by a urologist and a psychiatrist on the symptomatology of patients with functional urological disorders in a tertiary referral Pelvic Care Centre.

Setting

Retrospective observational cohort study in functional urological disorders in combination with psychosomatic co‐morbidity. When treatment by a urologist alone was not sufficient, the suitability for a multidisciplinary approach was considered i) if there was a susceptibility for psychiatric comorbidity, ii) if diagnostic procedures did not reveal a treatable somatic cause, or iii) if multiple failed somatic treatments did not relieve complaints. Patients underwent urological treatments before, without reduction of complaints, no treatable somatic cause could be found after diagnostic procedures; or patients suffered from psychiatric comorbidity.

Method

Outcome was measured using patient global impression of improvement, hospitality anxiety and depression scale (HADS), global assessment of functioning (GAF), and a health consumption questionnaire.

Results

A significant reduction in HADS‐depression score was found (p = 0.001) after multidisciplinary treatment. The GAF score increased from 61 to 80, leading to no more than slight impairment in social, occupational, or school functioning. Patients reported their situation as better in comparison with before multidisciplinary treatment. An association was found between pelvic pain and anxiety (p = 0.032) and panic disorder (p = 0.040). Psychological trauma was found to be associated with depression (p = 0.044), with an odds ratio of 2.93 (1.01–8.50). Psychological trauma coincided in 62.3% of patients with urological pain syndromes and in 83.3% with pelvic pain.

Conclusion

Overall results indicate that functional urological patients, previously refractory to urological treatment, benefit from an integrated care approach by urologists and psychiatrists. Explanation about the bladder–brain axis and the alarm falsification model enlightens understanding of urological and psychological contributions to functional syndromes and creates an opportunity for integrated care.

Guanylate cyclase-C agonists as peripherally acting treatments of chronic visceral pain

Irritable bowel syndrome (IBS) is a chronic gastrointestinal disorder characterized by abdominal pain and altered bowel habit that affects ~11% of the global population. Over the past decade, preclinical and clinical studies have revealed a variety of novel mechanisms relating to the visceral analgesic effects of guanylate cyclase-C (GC-C) agonists. Here we discuss the mechanisms by which GC-C agonists target the GC-C/cyclic guanosine-3',5'-monophosphate (cGMP) pathway, resulting in visceral analgesia as well as clinically relevant relief of abdominal pain and other sensations in IBS patients. Due to the preponderance of evidence we focus on linaclotide, a 14-amino acid GC-C agonist with very low oral bioavailability that acts within the gut. Collectively, the weight of experimental and clinical evidence supports the concept that GC-C agonists act as peripherally acting visceral analgesics.

An indirect comparison meta-analysis of noninvasive intravesical instillation and intravesical injection of botulinum toxin-A in bladder disorders

BACKGROUND

Botulinum toxin type A (BTX-A) intravesical instillation and BTX-A intravesical injection are both effective treatments or overactive bladder (OAB) and interstitial cystitis/bladder pain syndrome (IC/BPS), but direct comparative studies of the two treatments are lacking.

METHODS

We conducted a pairs-comparison meta-analysis and an adjusted indirect comparison meta-analysis extracting published data from randomized controlled trials in literature databases from the inception of each database to Aug. 31, 2021, evaluating efficacy and safety of BTX-A intravesical instillation and BTX-A intravesical injection. We also carried out a subgroup analysis.

RESULTS

We identified 24 trials in 21 studies were included in our study, of which 18 trials in 17 studies were BTX-A intravesical injections, 6 trials in 4 studies were BTX-A intravesical instillation. Compared with the normal saline injection, BTX-A intravesical injections for patients with OAB and IC/ BPS can obviously improve the symptoms of urinary frequency, urgency episode, UI and UUI, but BTX-A significantly increased the rate of urinary retention and urinary tract infection and increased PVR (p < 0.05). Adjusted indirect comparison meta-analysis showed that BTX-A intravesical injections was more effective than BTX-A intravesical instillation (p > 0.05). Surprisingly, BTX-A intravesical instillation had fewer side effects than BTX-A intravesical injections (p < 0.05).

CONCLUSIONS

Although BTX-A intravesical injections of OAB and IC/BPS has been significantly superior the BTX-A intravesical instillation, it has major side effects, but this needs to be confirmed by more large-scale, multicenter, direct comparison randomized controlled trials.

Components of the Endogenous Cannabinoid System as Potential Biomarkers for Interstitial Cystitis/Bladder Pain Syndrome

Interstitial cystitis/bladder pain syndrome (IC/BPS) is a chronic condition causing bladder pressure and pain. The condition is of unknown etiology and is often accompanied by other symptoms, including chronic pelvic pain, increased urinary urgency, and frequency. There is no definitive diagnosis for IC/BPS, and treatment options are currently limited to physical therapy and medications to help alleviate symptoms. The endogenous cannabinoid system (ECS) is an important regulator of numerous physiological systems, including the urinary system. Modulations of the ECS have been shown to be beneficial for IC/BPS-associated pain and inflammation in rodents. As an attempt to identify potential biomarkers for IC/BPS, we reviewed experimental studies where the components of the ECS have been quantified in experimental models of IC/BPS. Further investigations using well-defined animal models and patients’ data are required to obtain stronger evidence regarding the potential for ECS components to be definitive biomarkers for IC/BPS.

[Oral therapy for interstitial cystitis: pentosan polysulfate sodium]

INTRODUCTION

It is currently assumed that interstitial cystitis/bladder pain syndrome is caused by damage to the glycosaminoglycane layer on the urothelium of the urinary bladder. This layer can be repaired by oral therapy with pentosan polysulfate sodium. The focus of this article is on the history of this drug, its efficacy, its valuation in guidelines and especially the possible correlation with maculopathy.

METHODS

Literature research in PubMed and Embase.

RESULTS

PPS has a US and European approval for the therapy of IC characterised by glomerulations or a Hunner lesion detected by endoscopy and bladder distension. Its efficacy was proven in randomised trials. This led to a recommendation as a basic pharmaceutical therapy (in addition to behavioural intervention, dietary therapy or other drug treatments such as pain therapy). After a treatment period of six months, efficacy should be re-evaluated. Side-effects include mild haemodilution, nausea and loss of hair. Two publications of a US eye clinic have recently postulated a correlation between prolonged high-dose therapy with PPS and a special kind of maculopathy. Although this correlation was rejected in a large-scale health service study in Germany, a "red-hand-letter" led to the recommendation to perform an ophthalmologic examination before and during the treatment with PPS. Due to a pending litigation between payers and the distributor, PPS is currently out of trade in Germany. However, PPS can still be prescribed but must be imported from adjacent European countries. Unfortunately, these modalities have led to a significant undersupply of patients with IC/BPS. It is feared that this undersupply will increase further as the litigation is ongoing.

CONCLUSION

Being the only causally acting compound in the therapy of IC/BPS, PPS has an exceptional status. Although an ongoing litigation is pending in Germany and the correlation with maculopathy is still unclear, PPS must remain part of the current and future therapy of IC/BPS.

Association of Interstitial Cystitis/Bladder Pain Syndrome with Stress-Related Diseases: A Nationwide Population-Based Study

Background: Stress-related diseases (SRDs) are adjustment disorders triggered by stressful life changes. There is a growing body of evidence showing that stress plays an important role in the pathophysiology of IC/BPS. In the present study, we investigated the association between SRDs and a subsequent association of interstitial cystitis/bladder pain syndrome (IC/BPS). Methods: We performed a nested case-control study from the Longitudinal Health Insurance Database (LHID) of Taiwan. The two-year time-varying association between SRDs and IC/BPS was explored to distinguish the short- or long-term effects of these factors. We then conducted multiple conditional logistic regressions to evaluate the adjusted odds ratio (OR) of IC/BPS in patients with a history of SRDs. Results: A total of 1103 IC/BPS patients and 4412 non-IC/BPS patients were analyzed. For all SRDs, the significantly increased risks were obtained in 2 years before IC/BPS diagnosis, and the higher OR was observed within 3 months before the diagnosis of IC/BPS. Multiple conditional logistic regressions showed that patients who had prior medical care for urinary tract infection (OR = 10.95, 95% CI = 9.07 to 13.22), chronic obstructive pulmonary disease (OR = 1.48, 95% CI = 1.13 to 1.93), peptic ulcer (OR = 1.69, 95% CI = 1.37 to 2.09), inflammatory bowel syndrome (OR = 1.66, 95% CI = 1.21 to 2.29), autoimmune diseases (OR = 1.48, 95% CI = 1.11 to 1.97), depression (OR = 1.54, 95% CI = 1.24 to 1.91), sleep disorders (OR = 1.45, 95% CI = 1.19 to 1.78), and allergic rhinitis (OR = 1.29, 95% CI = 1.03 to 1.62) within 2 years had a significant risk of IC/BPS. Conclusions: Our study demonstrates that the health care for SRDs within the previous 2 years is associated with an increased risk of subsequent IC/BPS. The time-varying association provides an important insight that helps us to identify cases with IC/BPS, especially among patients with repeated UTI visits.

Systematic Review of Systemic and Neuraxial Effects of Acetaminophen in Preclinical Models of Nociceptive Processing

Acetaminophen (APAP) in humans has robust effects with a high therapeutic index in altering postoperative and inflammatory pain states in clinical and experimental pain paradigms with no known abuse potential. This review considers the literature reflecting the preclinical actions of acetaminophen in a variety of pain models. Significant observations arising from this review are as follows: 1) acetaminophen has little effect upon acute nociceptive thresholds; 2) acetaminophen robustly reduces facilitated states as generated by mechanical and thermal hyperalgesic end points in mouse and rat models of carrageenan and complete Freund’s adjuvant evoked inflammation; 3) an antihyperalgesic effect is observed in models of facilitated processing with minimal inflammation (eg, phase II intraplantar formalin); and 4) potent anti-hyperpathic effects on the thermal hyperalgesia, mechanical and cold allodynia, allodynic thresholds in rat and mouse models of polyneuropathy and mononeuropathies and bone cancer pain. These results reflect a surprisingly robust drug effect upon a variety of facilitated states that clearly translate into a wide range of efficacy in preclinical models and to important end points in human therapy. The specific systems upon which acetaminophen may act based on targeted delivery suggest both a spinal and a supraspinal action. Review of current targets for this molecule excludes a role of cyclooxygenase inhibitor but includes effects that may be mediated through metabolites acting on the TRPV1 channel, or by effect upon cannabinoid and serotonin signaling. These findings suggest that the mode of action of acetaminophen, a drug with a long therapeutic history of utilization, has surprisingly robust effects on a variety of pain states in clinical patients and in preclinical models with a good therapeutic index, but in spite of its extensive use, its mechanisms of action are yet poorly understood.

Diagnostic Utility of Serum and Urinary Metabolite Analysis in Patients with Interstitial Cystitis/Painful Bladder Syndrome

OBJECTIVE

To identify the potential biomarkers of interstitial cystitis/painful bladder syndrome (IC), a chronic syndrome of bladder-centric pain with unknown etiology that has an adverse impact on quality of life, we analyzed the urine and serum metabolomes of a cohort of IC patients and non-disease controls (NC).

METHODS

Home collection of serum and urine samples was obtained from 19 IC and 20 NC females in the Veterans Affairs (VA) Health Care System. IC was diagnosed independently by thorough review of medical records using established criteria. Biostatistics and bioinformatics analyses, including univariate analysis, unsupervised clustering, random forest analysis, and metabolite set enrichment analysis (MSEA), were then utilized to identify potential IC biomarkers.

RESULTS

Metabolomics profiling revealed distinct expression patterns between NC and IC. Random forest analysis of urine samples suggested discriminators specific to IC; these include phenylalanine, purine, 5-oxoproline, and 5-hydroxyindoleacetic acid. When these urinary metabolomics-based analytes were combined into a single model, the AUC was 0.92, suggesting strong potential clinical value as a diagnostic signature. Serum-based metabolomics did not provide potential IC discriminators.

CONCLUSION

Analysis of serum and urine revealed that women with IC have distinct metabolomes, highlighting key metabolic pathways that may provide insight into the pathophysiology of IC. The findings from this pilot study suggest that integrated analyses of urinary metabolites, purine, phenylalanine, 5-oxoproline, and 5-HIAA, can lead to promising IC biomarkers for pathophysiology of IC. Validation of these results using a larger dataset is currently underway.

Interstitial cystitis/bladder pain syndrome patient is associated with subsequent increased risks of outpatient visits and hospitalizations: A population-based study

Interstitial cystitis/bladder pain syndrome (IC/BPS) is not only a chronic urinary bladder pain syndrome but is also associated with multifactorial etiology. Our study aimed to test the hypothesis that IC/BPS is associated with subsequent increased risks of outpatient visits and hospitalizations. Using nationwide database, the diagnoses were based on the International Classification Codes (ICD-9-CM) (595.1) of at least three outpatient services during 2002-2008, (n = 27,990) and cystoscopic finding Hunner type and/or glomerulation with pre-audit criteria. All recruited cases monitored for subsequent outpatient visits and hospitalizations for 2 years, including all-cause and specialty-specific departments, were classified according to medical specialty and age group (<40, 40-60, ≥60 years of age). IC/BPS patients have more overall outpatient department (OPD) visits and an overall adjusted incidence rate ratio (IRR) of 1.64. As for specialty, IRRs were higher in psychiatry (2.75), Chinese medicine (2.01), and emergency medicine (2.00), besides urology and gynecology. The IRRs decreased as age advanced (2.01, 1.71, and 1.44, respectively), except for gynecology (2.42, 2.52, and 2.81). A similar phenomenon happens in hospitalization with IRR of 1.69. Due to claim data characteristics, whether ulcer type IC/BPS findings can be deductive to non-ulcer type remains inclusive. Current results indicate the impacts of healthcare burden in broad spectrum about IC/PBS patients. IC/BPS has been suggested to be associated with lower threshold of healthcare visits and some coexisting disease and is comprised of systemic dysregulation, and is beyond the scope of local bladder-urethra disease. Adequate recognition of associated or comorbid factors and possible recommendation or referral for IC/BPS patients can help provide better healthcare quality.

A Systematic Review of Therapeutic Approaches Used in Experimental Models of Interstitial Cystitis/Bladder Pain Syndrome

Interstitial cystitis/bladder pain syndrome (IC/BPS) is a multifactorial, chronic bladder disorder with limited therapeutic options currently available. The present review provides an extensive overview of therapeutic approaches used in in vitro, ex vivo, and in vivo experimental models of IC/BPS. Publications were identified by electronic search of three online databases. Data were extracted for study design, type of treatment, main findings, and outcome, as well as for methodological quality and the reporting of measures to avoid bias. A total of 100 full-text articles were included. The majority of identified articles evaluated therapeutic agents currently recommended to treat IC/BPS by the American Urological Association guidelines (21%) and therapeutic agents currently approved to treat other diseases (11%). More recently published articles assessed therapeutic approaches using stem cells (11%) and plant-derived agents (10%), while novel potential drug targets identified were proteinase-activated (6%) and purinergic (4%) receptors, transient receptor potential channels (3%), microRNAs (2%), and activation of the cannabinoid system (7%). Our results show that the reported methodological quality of animal studies could be substantially improved, and measures to avoid bias should be more consistently reported in order to increase the value of preclinical research in IC/BPS for potential translation to a clinical setting.

Activation of MrgprA3 and MrgprC11 on Bladder-Innervating Afferents Induces Peripheral and Central Hypersensitivity to Bladder Distension

Understanding the sensory mechanisms innervating the bladder is paramount to developing efficacious treatments for chronic bladder hypersensitivity conditions. The contribution of Mas-gene-related G protein-coupled receptors (Mrgpr) to bladder signaling is currently unknown. Using male and female mice, we show with single-cell RT-PCR that subpopulations of DRG neurons innervating the mouse bladder express MrgprA3 (14%) and MrgprC11 (38%), either individually or in combination, with high levels of coexpression with Trpv1 (81%-89%). Calcium imaging studies demonstrated MrgprA3 and MrgprC11 agonists (chloroquine, BAM8-22, and neuropeptide FF) activated subpopulations of bladder-innervating DRG neurons, showing functional evidence of coexpression between MrgprA3, MrgprC11, and TRPV1. In ex vivo bladder-nerve preparations, chloroquine, BAM8-22, and neuropeptide FF all evoked mechanical hypersensitivity in subpopulations (20%-41%) of bladder afferents. These effects were absent in recordings from Mrgpr-clusterΔ^-/- mice. In vitro whole-cell patch-clamp recordings showed that application of an MrgprA3/C11 agonist mixture induced neuronal hyperexcitability in 44% of bladder-innervating DRG neurons. Finally, in vivo instillation of an MrgprA3/C11 agonist mixture into the bladder of WT mice induced a significant activation of dorsal horn neurons within the lumbosacral spinal cord, as quantified by pERK immunoreactivity. This MrgprA3/C11 agonist-induced activation was particularly apparent within the superficial dorsal horn and the sacral parasympathetic nuclei of WT, but not Mrgpr-clusterΔ^-/- mice. This study demonstrates, for the first time, functional expression of MrgprA3 and MrgprC11 in bladder afferents. Activation of these receptors triggers hypersensitivity to distension, a critically valuable factor for therapeutic target development.SIGNIFICANCE STATEMENT Determining how bladder afferents become sensitized is the first step in finding effective treatments for common urological disorders such as overactive bladder and interstitial cystitis/bladder pain syndrome. Here we show that two of the key receptors, MrgprA3 and MrgprC11, that mediate itch from the skin are also expressed on afferents innervating the bladder. Activation of these receptors results in sensitization of bladder afferents, resulting in sensory signals being sent into the spinal cord that prematurely indicate bladder fullness. Targeting bladder afferents expressing MrgprA3 or MrgprC11 and preventing their sensitization may provide a novel approach for treating overactive bladder and interstitial cystitis/bladder pain syndrome.

Cognitive components of behavioral therapy for overactive bladder: a systematic review

INTRODUCTION AND HYPOTHESIS

Behavioral therapy is the first-line treatment for overactive bladder (OAB); however, the cognitive components of behavioral therapy for OAB have not been evaluated. The purposes of this systematic review were to describe the cognitive components of behavioral therapy for OAB and evaluate their effectiveness as well as to describe their rationale and origins.

METHODS

Searches were conducted on the PubMed, CINAHL, Web of Science, Cochrane and PEDro databases. Inclusion criteria were single-arm or randomized controlled trials on OAB treatment that utilized behavioral therapy, with a description of a cognitive component of the behavioral therapy. Study participants were neurologically intact adults (n = 1169). Study methodological quality was assessed with the PEDro and Newcastle-Ottawa scales.

RESULTS

Five studies were included, published between 2009 and 2020. Methodological quality was variable. All studies reported a reduction of symptoms in participants receiving behavioral therapy. Cognitive components of behavioral therapy were not extensively described. Distraction was the most common cognitive strategy for managing urgency. The relative impact of the cognitive aspect of behavioral therapy could not be evaluated, and the cognitive aspects of behavioral therapy appear to be accepted wisdom, traceable to several key authors, that has not been subjected to scientific investigation.

CONCLUSIONS

Behavioral therapy for OAB appears useful, but its cognitive components are not well described, their relative importance has not been evaluated or ascertained, nor have they been rigorously studied.