Interstitial cystitis: an unsolved enigma

Modified Botulinum Toxin Type A Injections Improve Symptoms Associated With Interstitial Cystitis/Bladder Pain Syndrome in Women: A Retrospective Cohort Study

OBJECTIVE

To investigate the efficacy and safety of modified botulinum toxin type A (BoNT-A) injections (with additional periurethral injection [PUI] of BoNT-A) for the treatment of interstitial cystitis/bladder pain syndrome (IC/BPS).

METHODS

This single-center, retrospective cohort study included 52 adult female patients with IC/BPS, with 24 patients receiving conventional BoNT-A injections and 28 receiving modified BoNT-A injections. The primary outcome measure was patient-reported global response assessment. Secondary outcomes included daytime frequency, nocturia, number of urinary urgency episodes in the voiding diary, pain visual analog score, O'Leary-Sant interstitial cystitis symptom index and interstitial cystitis problem index, pelvic pain and urgency/frequency scores, risk factors for recurrence, and postoperative recurrence-free time.

RESULTS

The median duration of follow-up was 16.0 months (interquartile range 11.75-21 months). Patients who underwent modified BoNT-A injections showed significant improvement in postoperative global response assessment, symptom questionnaires, and pain assessment compared with those who underwent conventional surgery. A statistically significant difference was observed between the 2 groups in terms of recurrence-free time (12.5 vs 18.0 months, P = .02). Subgroup analysis suggested that additional PUI of BoNT-A was more effective in patients with combined severe periurethral pain. No serious complications occurred in both groups, and all minor postoperative complications were temporary.

CONCLUSION

Modified BoNT-A injection is an effective treatment for IC/BPS that significantly reduces pain and improves voiding symptoms. It is particularly effective in patients with combined periurethral pain. In such patients, PUI of BoNT-A should be added to the routine intravesical injection of BoNT-A.

Determination of the roles of cADPR and NAADP as intracellular calcium mobilizing messengers in S1P-induced contractions in rat bladders having IC/PBS

AIMS

Interstitial cystitis/painful bladder syndrome (IC/PBS) is characterized by lower abdominal pain and increased frequency and urgency of urine. Sphingosine 1-phosphate (S1P) is a bioactive sphingolipid that plays role in calcium homeostasis in smooth muscle. The intracellular calcium mobilizing secondary messengers are also involved in smooth muscle contraction. The role of intracellular calcium storing depots in S1P-induced contraction was investigated in permeabilized detrusor smooth muscle having cystitis.

MAIN METHODS

IC/PBS was induced by cyclophosphamide injection. The detrusor smooth muscle strips isolated from rats were permeabilized with β-escin.

KEY FINDINGS

S1P-induced contraction was increased in cystitis. S1P-induced enhanced contraction was inhibited by cyclopiazonic acid, ryanodine and heparin showing involvement of sarcoplasmic reticulum (SR) calcium stores. Inhibition of S1P-induced contraction by bafilomycin and NAADP suggested the participation of lysosome-related organelles.

SIGNIFICANCE

IC/PBS triggers S1P-induced increase in intracellular calcium from SR and lysosome-related organelles in permeabilized detrusor smooth muscle.

Overactive bladder with urodynamic study-induced bladder pain: An overactive bladder subtype with symptoms similar to those of interstitial cystitis/painful bladder syndrome

Overactive bladder (OAB) and interstitial cystitis/painful bladder syndrome (IC/PBS) are 2 lower urinary tract disorders with urgency and bladder pain for diagnosis and with several other shared symptoms. Because of their overlapping symptoms, precise differential diagnosis of OAB and IC/PBS remains difficult. Thus, we characterize a subgroup of OAB with bladder pain (OAB-BP) that can be differentiated from OAB alone by urodynamic study (UDS) findings. We also further examined the clinical presentations and urodynamic parameters of OAB alone, OAB-BP, and IC/PBS. Data were collected between September 2018 and April 2019. Patients were categorized into 3 groups, OAB-alone (no bladder pain during UDS, n = 39), OAB-BP (with bladder pain during UDS, n = 35), and IC/PBS (the comparator, n = 39). Chi-square tests were used to compare OAB alone, OAB-BP, and IC/PBS with respect to their clinical presentations and urodynamic parameters. Factors with P < .05 were further analyzed through post hoc comparisons with Bonferroni adjustment. An unique subgroup of OAB patients was identified (i.e., OAB-BP), bladder pain can only be induced at maximal cytometric capacity during UDS. We also identified that the case histories and UDS parameters (e.g., low first desire, normal desire, and maximum cytometric capacity) of the OAB-BP group were more similar to those of the IC/PBS group than to those of the OAB-alone group. The OAB-BP group and the IC/PBS group reported more intrusive, longer-lasting symptoms before their final diagnoses, more extensive family history of urinary tract disorder, and more associated comorbidities (e.g., irritable bowel syndrome, and myofascial pain) than the OAB-alone group. The UDS assessment induced bladder pain in the OAB-BP group to reveal their hidden symptoms. Careful attention to patient history and sophisticated UDS evaluation may help to identify this unique OAB group.

How useful is kidney biopsy for the management of glomerulopathies in the elderly?

BACKGROUND

The use of kidney biopsy in elderly individuals is still matter of discussion. The purpose of this study is to assess the utility of kidney biopsy for the management of glomerulopathies in an Eastern European cohort, targeting patients older than 65 years.

METHODS

This retrospective study included 875 adults (147 older than 65 years), with biopsy-proven glomerulopathies, followed up for 71.1 (95% CI 68.2-73.9) months. The primary endpoint was chronic renal replacement therapy initiation. Statistical evaluation was performed with IBM SPSS software version 20, Analyse-it, and SAS Studio. The Kaplan-Meier method was used to estimate the time to death and the log-rank test was used for comparisons. The multivariate Cox proportional hazard analysis was used to evaluate the risk of death.

RESULTS

Secondary glomerulopathies were more frequent in patients aged > 65 years (52.4% vs. 41.9%, p = 0.004). Membranous nephropathy and amyloidosis were the most frequent primary and secondary glomerulopathies in this age group. Kidney biopsy complications were low (< 4%) in both age groups. In 42% of the elderly, the result of biopsy guided the immunosuppressive therapy. While the all-cause mortality rate was higher (OR 4.2; 95% CI 2.7-6.7; p < 0.0001) in elderly individuals, the rate of renal replacement therapy initiation was similar (31.3 vs 26%; p = 0.1) in both age groups. In the competitive risk analysis, kidney survival was similar irrespective of age [CIF 0.4 (95% CI 0.26-0.53) vs. 0.34 (95% CI 0.28-0.39), p = 0.08]. However, after adjusting for the confounding factors, younger age was associated with an increased risk of renal replacement therapy (HR = 1.57, p = 0.01), along with secondary glomerulopathies.

CONCLUSION

The diagnosis of an underlying glomerulopathy guided the therapy in almost one-half of the elderly patients who underwent a kidney biopsy, provided important prognostic information and had a low complications rate; kidney biopsy may therefore be considered a safe, reliable procedure in the management of glomerulopathies, even in patients over 65 years of age.

Bladder pain syndrome/interstitial cystitis response to nerve blocks and trigger point injections

Objectives

Bladder pain syndrome (BPS)/interstitial cystitis (IC) is a debilitating condition characterised by bladder/pelvic pain and pressure as well as persistent or recurrent urinary symptoms in the absence of an identifiable cause. It is hypothesised that in addition to organ specific visceral hypersensitivity, contributions of the hypertonic pelvic floor, peripheral sensitisation, and central sensitisation exacerbate this condition. The aim of this paper is to investigate outcomes of treating underlying neuromuscular dysfunction and neuro-plastic mechanisms in BPS/IC patients.

Methods

A retrospective chart review of 84 patients referred to an outpatient pelvic rehabilitation centre with a diagnosis of BPS/IC given to them by a urologist. All 84 patients failed to progress after completing 6 weeks of pelvic floor physical therapy and underwent an institutional review board approved protocol (IRB# 17-0761) consisting of external ultrasound-guided trigger point injections to the pelvic floor musculature, peripheral nerve blocks of the pudendal and posterior femoral cutaneous nerves and continued pelvic floor physical therapy once weekly for 6 weeks. Pelvic pain intensity and functionality were measured pretreatment and 3 months posttreatment using Visual Analogue Scale (VAS) and Functional Pelvic Pain Scale (FPPS).

Results

Pretreatment, mean VAS was 6.23 ± 2.68 (95% CI 5.65 to 6.80). Posttreatment mean VAS was 3.90 ± 2.63 (95% CI 3.07-4.74). Mean FPPS before treatment was 11.98 ± 6.28 (95% CI 10.63 to 13.32). Posttreatment mean FPPS was 7.68 ± 5.73 (95% CI 6.45-8.90). Analysis of subcategories within FPPS indicated highest statistically significant improvement in the categories of bladder, intercourse and working.

Conclusions

Analysis suggests the treatment was effective at ameliorating bladder pain and function including urinary urgency, frequency, and burning in BPS/IC patients.

National prevalence of IC/BPS in women and men utilizing veterans health administration data

Importance

Interstitial cystitis/bladder pain syndrome (IC/BPS) is an immense burden to both patients and the American healthcare system; it is notoriously difficult to diagnose. Prevalence estimates vary widely (150-fold range in women and >500-fold range in men).

Objectives

We aimed to create accurate national IC/BPS prevalence estimates by employing a novel methodology combining a national population-based dataset with individual chart abstraction.

Study design

In this epidemiological survey, all living patients, with ≥2 clinic visits from 2016 to 2018 in the Veterans Health Administration, with an ICD-9/10 code for IC/BPS (n = 9,503) or similar conditions that may represent undiagnosed IC/BPS (n = 124,331), were identified (other were controls n = 5,069,695). A detailed chart review of random gender-balanced samples confirmed the true presence of IC/PBS, which were then age- and gender-matched to the general US population.

Results

Of the 5,203,529 patients identified, IC/BPS was confirmed in 541 of 1,647 sampled charts with an IC/BPS ICD code, 10 of 382 charts with an ICD-like code, and 3 of 916 controls. After age- and gender-matching to the general US population, this translated to national prevalence estimates of 0.87% (95% CI: 0.32, 1.42), with female and male prevalence of 1.08% (95% CI: 0.03, 2.13) and 0.66% (95% CI: 0.44, 0.87), respectively.

Conclusions

We estimate the prevalence of IC/BPS to be 0.87%, which is lower than prior estimates based on survey data, but higher than prior estimates based on administrative data. These potentially represent the most accurate estimates to date, given the broader and more heterogeneous population studied and our novel methodology of combining in-depth chart abstraction with administrative data.

Therapeutic interventions to urologic chronic pelvic pain syndrome and UPOINT system for clinical phenotyping: How far are we?

The assessment and management of urologic chronic pelvic pain syndrome (UCPPS), is controversial. It is classified by voiding symptoms, pelvic pain, and bladder pain, which is weekly treated, weekly understood, and bothersome. In the aspect of clinical efforts and research to help people with this syndrome have been hampered by the deficiency of a widely reliable, accepted, and a valuable tool to evaluate the patient symptoms and quality of life (QoL) impact. However, the etiology comes into sight is multifactorial, and available treatment options have been imprecise considerably in present years. We compiled the published literature on the assessment of the syndrome, a tentative role of pharmacological and non-pharmacological (conservative, alternative, and invasive therapy) interventions in eradicating the disease as well as improving symptoms. The previously published literature on animal models has established the association of immune systems in the etiology, pathogenesis, and progression of the disease. The UPOINT system for clinical phenotyping of UCPPS patients has six predefined domains that direct multimodal therapy, which would lead to significant symptom improvement in the medical field. The narrative review aims to scrutinize the fluctuating scientist's views on the evaluation of patient and multimodal treatment of the UPOINT system.

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.

Lifestyle and behavioral modifications made by patients with interstitial cystitis

Interstitial cystitis/bladder pain syndrome (IC/BPS) negatively affects the quality of life. In this study, we investigated the lifestyle behavioral changes patients with IC/BPS make to cope with their symptoms. This prospective study was conducted between August 2018 and June 2019. All patients had a primary symptom of suprapubic pain with a full bladder and other lower urinary tract symptoms for more than 6 weeks as well as cystoscopic findings. All participants completed our self-developed questionnaire, which included informations about their living and work environment, occupational garments, dietary habits, and personal habits. Continuous variables were compared using an independent sample t test, and categorical variables were compared using a chi-square test. We recruited 86 patients with IC/BPS and age-matched 86 controls without IC/BPS. In our study, patients with IC/BPS had more cranberry intake (45.34% vs. 5.81%, P < 0.05) than non-IC/BPS controls; the IC/BPS group had decreased consumption of coffee and spicy food; and wore less makeup or special work garments. In conclusion, patients with IC/BPS tend to make several lifestyle behavioral changes to cope with their symptoms.

MicroRNA-495 alleviates ulcerative interstitial cystitis via inactivating the JAK-STAT signaling pathway by inhibiting JAK3

INTRODUCTION AND HYPOTHESIS

As a notable chronic disorder, the incidence of interstitial cystitis (IC) has been documented to have increased among the female population with activity in microRNA-495 (miR-495) implicated in this disease. The current study was aimed at elucidating the effects associated with miR-495 on the inflammatory response and bladder fibrosis in rats with ulcerative IC via the JAK-STAT pathway by targeting JAK3.

METHODS

Ulcerative IC rat models were established. The targeting relationship between JAK3 and miR-495 was evaluated using luciferase reporter assay. After gain- or loss-of-function assays, mast-cell infiltration was assessed using toluidine blue staining, bladder fibrosis using Masson staining, and NO content using nitrate reductase method. JAK3 protein expression was detected by immunohistochemistry, JAK3, STAT1, STAT3, TGFβ-1, Col-I, Col-III, JAK1, JAK2, p-STAT1, and p-STAT3 expression by RT-qPCR and Western blot analysis, and serum IL-6, IL-8, IL-10, IL-17, and TNF-α levels in rats by ELISA.

RESULTS

Following transfection of overexpressed miR-495 or siRNA-JAK3, a diminished degree of mast-cell infiltration, number of mast cells, bladder fibrosis, NO content, JAK3-positive expression, mRNA expression of JAK3, STAT1, STAT3, TGFβ-1, Col-I, Col-III, protein expression of JAK1, JAK2, JAK3, p-STAT1, p-STAT3, and expression of IL-6, IL-8, IL-10, IL-17, and TNF-α were identified.

CONCLUSIONS

Collectively, our key findings provide evidence supporting the notion that the overexpression of miR-495 ameliorates inflammatory response and bladder fibrosis in ulcerative IC rat models via inactivation of the JAK-STAT signaling pathway by inhibiting JAK3.

The Urothelium: Life in a Liquid Environment

The urothelium, which lines the renal pelvis, ureters, urinary bladder, and proximal urethra, forms a high-resistance but adaptable barrier that surveils its mechanochemical environment and communicates changes to underlying tissues including afferent nerve fibers and the smooth muscle. The goal of this review is to summarize new insights into urothelial biology and function that have occurred in the past decade. After familiarizing the reader with key aspects of urothelial histology, we describe new insights into urothelial development and regeneration. This is followed by an extended discussion of urothelial barrier function, including information about the roles of the glycocalyx, ion and water transport, tight junctions, and the cellular and tissue shape changes and other adaptations that accompany expansion and contraction of the lower urinary tract. We also explore evidence that the urothelium can alter the water and solute composition of urine during normal physiology and in response to overdistension. We complete the review by providing an overview of our current knowledge about the urothelial environment, discussing the sensor and transducer functions of the urothelium, exploring the role of circadian rhythms in urothelial gene expression, and describing novel research tools that are likely to further advance our understanding of urothelial biology.

Characterization and Validation of a Chronic Model of Cyclophosphamide-Induced Interstitial Cystitis/Bladder Pain Syndrome in Rats

Interstitial cystitis/Bladder Pain Syndrome (IC/BPS) is a chronic inflammatory disease characterized by visceral pain and voiding symptoms. IC/BPS is still an unsolved enigma with ineffective diagnosis criteria and treatment. A main limitation in IC/BPS understanding is the lack of appropriate preclinical model. Cyclophosphamide (CYP) is commonly used as an experimental model for IC/BPS in rodent. However, the proposed models are very aggressive, contrasting with what occurs in clinic, and often associated with severe toxicity and high mortality rate. In addition, visceral pain, the hallmark symptom of IC/BPS, has been validated in only few of them. In this study, we developed a chronic model of CYP-induced IC/BPS in female rat. In our protocol, no severe weight loss occurred and the survival rate was 100%. In accordance to human pathology, chronic CYP-injected rats developed severe painful behavior whereas only sparse inflammation was observed. Inflammatory response was characterized by bladder edema and focal urothelial damage but absence of massive infiltrate. This chronic model showed persistent symptoms indicative for a central sensitization mechanism. We further demonstrate that CYP-induced chronic visceral pain was significantly reduced by curative treatment with clinically relevant compounds (gabapentin, ibuprofen, and Ialuril^®). We therefore developed and validated a rat model of chronic cystitis that shares strong similarity with human non-ulcerative IC/BPS features without overtly affecting the animal health. This model will thus provide mechanistic insights of the disease and help to evaluate therapeutic agents for IC/BPS.

Application of Adult and Pluripotent Stem Cells in Interstitial Cystitis/Bladder Pain Syndrome Therapy: Methods and Perspectives

Interstitial cystitis/bladder pain syndrome (IC/BPS) is a multifactorial, chronic disease without definite etiology characterized by bladder-related pelvic pain. IC/BPS is associated with pain that negatively affects the quality of life. There are various therapeutic approaches against IC/BPS. However, no efficient therapeutic agent against IC/BPS has been discovered yet. Urothelium dysfunction is one of the key factors of IC/BPS-related pathogenicity. Stem cells, including adult stem cells (ASCs) and pluripotent stem cells (PSCs), such as embryonic stem cells (ESCs) and induced PSCs (iPSCs), possess the abilities of self-renewal, proliferation, and differentiation into various cell types, including urothelial and other bladder cells. Therefore, stem cells are considered robust candidates for bladder regeneration. This review provides a brief overview of the etiology, pathophysiology, diagnosis, and treatment of IC/BPS as well as a summary of ASCs and PSCs. The potential of ASCs and PSCs in bladder regeneration via differentiation into bladder cells or direct transplantation into the bladder and the possible applications in IC/BPS therapy are described in detail. A better understanding of current studies on stem cells and bladder regeneration will allow further improvement in the approaches of stem cell applications for highly efficient IC/BPS therapy.

The misdiagnosis of interstitial cystitis/bladder pain syndrome in a VA population

AIMS

The complexity of Interstitial Cystitis/bladder Pain Syndrome (IC/BPS) has led to a great deal of uncertainty around the diagnosis and prevalence of the condition. Under the hypothesis that IC/BPS is frequently misdiagnosed, we sought to assess the accuracy of the ICD-9/ICD-10 code for IC/BPS using a national data set.

METHODS

Using the Veterans Affairs Informatics and Computing Infrastructure, we identified a random sample of 100 patients with an ICD-9/ICD-10 diagnosis of IC/BPS (595.1/N30.10) by querying all living patients in the Veterans Affairs (VA) system. We purposely sampled men and women equally to better understand gender-specific practice patterns. Patients were considered a correct IC/BPS diagnosis if they had two visits complaining of bladder-centric pain in the absence of positive urine culture at least 6 weeks apart. Patients were considered not to have IC/BPS if they had a history of pelvic radiation, systemic chemotherapy, metastatic cancer, or bladder cancer.

RESULTS

Of the 100 patients, 48 were female and 52 were male. Five had prior radiation, one had active cancer, and 10 had bladder cancer (all male), and an additional fifteen had insufficient records. Of the remaining 69 patients, 43% did not have IC/BPS. Of these patients who did not have IC/BPS, 43% complained only of overactive bladder (OAB) symptoms, which was more common in women (63%) than men (21%), P = .003.

CONCLUSIONS

In our small sample from a nationwide VA system, results indicate that IC/BPS has a high misdiagnosis rate. These findings shed light on the gender-specific diagnostic complexity of IC/BPS.

Urinary K+ promotes irritative voiding symptoms and pain in the face of urothelial barrier dysfunction

The internal surface of the bladder is lined by the urothelium, a stratified epithelium that forms an impermeable barrier to water and urine constituents. Abnormalities in the urothelial barrier have been described in certain forms of cystitis and were hypothesized to contribute to irritative voiding symptoms and pain by allowing the permeation of urinary K+ into suburothelial tissues, which then alters afferent signaling and smooth muscle function. Here, we examined the mechanisms underlying organ hyperactivity and pain in a model of cystitis caused by adenoviral-mediated expression of claudin-2 (Cldn2), a tight junction protein that forms paracellular pores and increases urothelial permeability. We found that in the presence of a leaky urothelium, intravesical K+ sensitizes bladder afferents and enhances their response to distension. Notably, dietary K+ restriction, a maneuver that reduces urinary K+, prevented the development of pelvic allodynia and inflammation seen in rats expressing Cldn2. Most importantly, intravesical K+ causes and is required to maintain bladder hyperactivity in rats with increased urothelial permeability. Our study demonstrates that in the face of a leaky urothelium, urinary K+ is the main determinant of afferent hyperexcitability, organ hyperactivity and pain. These findings support the notion that voiding symptoms and pain seen in forms of cystitis that coexist with urothelial barrier dysfunction could be alleviated by cutting urinary K+ levels.

Risk of Urinary Tract Carcinoma among Subjects with Bladder Pain Syndrome/Interstitial Cystitis: A Nationwide Population-Based Study

Objective

To investigate the subsequent risks of urinary tract cancers among individuals with bladder pain syndrome/interstitial cystitis (BPS/IC), and gender differences, as well as the effect of associated comorbidity using a population-based administrative database in Taiwan.

Patients and Methods

BPS/IC subjects (10192) and their age- and sex-matched non-BPS/IC control subjects (30576), who had no previous upper urinary tract cancer (UUC), bladder cancer (BC), and prostate cancer (PC), subsequently developed these disorders from the recruited date between 2002 and 2008 and the end of follow-up 2011. A Cox proportional hazards regression model was constructed to estimate the risk of subsequent UUC, BC, and PC following a diagnosis of IC/BPS. The effect of associated comorbidities was measured by Charlson Comorbidity Index (CCI). The risk of outcomes was assessed with Kaplan-Meier curves.

Results

In the BPS/IC subjects, 37 (0.36%) received a diagnosis of BC, and 22 (0.22%) received a diagnosis of UUC; both were significantly higher than the control group, 19 (0.06%) for BC and 30 (0.10%) for UUC. Cox proportional analysis revealed that the adjusted HR for BC and UUC during the follow-up period for patients with IC/BPS was 5.44 (95% CI: 3.10-9.54) and 1.97 (95% CI: 1.13-3.45) than that of comparison subjects. The HRs went up to 5.66 (95% CI: 3.21-9.99) and 2.01 (95% CI: 1.14-3.55) after adjusted by Comorbidity Index (CCI). The male BPS/IC patients have a higher adjusted HR for BC; however, female patients have a higher adjusted HR for both BC and UUC. The adjusted HR for PC has no difference between BPS/IC and control group.

Conclusion

Patients with BPS/IC are at risk of developing BC in both males and females, and UUC in females. This result reminds physicians to evaluate the potential risk of subsequent development of BC and UUC among individuals with BPS/IC.

Health Education and Symptom Flare Management Using a Video-based m-Health System for Caring Women With IC/BPS

OBJECTIVE

To assess effectiveness of the video-based m-health system providing videos dictated by physicians for health education and symptom self-management for patients with Interstitial cystitis/bladder pain syndrome (IC/BPS).

METHODS

An m-health system was designed to provide videos for weekly health education and symptom flare self-management. O'Leary-Sant index and visual analogue scale as well as SF-36 health survey were administrated to evaluate the disease severity and quality of life (QoL), respectively. A total of 60 IC/BPS patients were recruited and randomly assigned to either control group (30 patients) or study group (30 patients) in sequence depending on their orders to visit our urological clinic. Patients in both control and study groups received regular treatments, while those in the study group received additional video-based intervention. Statistical analyses were conducted to compare the outcomes between baseline and postintervention for both groups. The outcomes of video-based intervention were also compared with the text-based intervention conducted in our previous study.

RESULTS

After video-based intervention, patients in the study group exhibited significant effect manifested in all disease severity and QoL assessments except the pain visual analogue scale, while no significance was found in the control group. Moreover, the study group exhibited more significant net improvements than the control group in 7 SF-36 constructs, except the mental health. The limitations include short intervention duration (8 weeks) and different study periods between text-based and video-based interventions.

CONCLUSION

Video-based intervention is effective in improving the QoL of IC/BPS patients and outperforms the text-based intervention even in a short period of intervention.

Establishment of a Novel Autoimmune Experimental Model of Bladder Pain Syndrome/Interstitial Cystitis in C57BL/6 Mice

The aim of this study is to identify whether vaccinating twice with bladder homogenate can establish a new model of experimental autoimmune cystitis (EAC) in C57BL/6 strain mice. C57BL/6 mice were vaccinated with bladder homogenate in complete Freund's adjuvant (CFA) and boost immunized with bladder homogenate in incomplete Freund's adjuvant (IFA) after 2 weeks were used as the EAC model. Mice immunized with phosphate-buffered saline (PBS) in CFA or IFA were used as the control. Micturition habits and suprapubic-pelvic pain threshold were measured 4 weeks after primary immunization. Bladder to body weight ratios and expression of inflammatory cytokines and neurokinin 1 receptor (NK1R) were then examined. Histologic and immunohistochemical examination of the bladder was carried out, and IL-1β, IFN-γ, and TNF-α production by the kidneys, liver, and lungs was also tested. Double-immunized mice were extensively sensitive to pressure applied on the pelvic area (P < 0.001). Compared to single-immunized mice or controls, double-immunized mice showed more micturition frequency, lower urine output per micturition, higher bladder to body weight ratio, and significant elevation in the expression of inflammatory cytokines, including IL-1β, IL-4, IL-6, IL-10, IFN-γ, and TNF-α (all P < 0.05). NK1R gene expression was significantly increased in double-immunized mice compared to the other three groups (P < 0.001). A nonspecific immune response occurred in the liver but was much weaker than bladder inflammation. Our dual immunization EAC model in C57BL/6 mice can effectively mimic the symptoms and pathophysiologic characteristics of BPS/IC and thus can be widely used to investigate the pathogenesis and therapeutic strategies of BPS/IC.

Effects of herpes simplex virus vectors encoding poreless TRPV1 or protein phosphatase 1α in a rat cystitis model induced by hydrogen peroxide

Enhanced afferent excitability is considered to be an important pathophysiological basis of interstitial cystitis/bladder pain syndrome (IC/BPS). In addition, transient receptor potential vanilloid-1 (TRPV1) receptors are known to be involved in afferent sensitization. Animals with hydrogen peroxide (HP)-induced cystitis have been used as a model exhibiting pathologic characteristics of chronic inflammatory condition of the bladder. This study investigated the effect of gene therapy with replication-defective herpes simplex virus (HSV) vectors encoding poreless TRPV1 (PL) or protein phosphatase 1 α (PP1α), a negative regulator of TRPV1, using a HP-induced rat model of cystitis. HSV vectors encoding green fluorescent protein, PL or PP1α were inoculated into the bladder wall of female rats. After 1 week, 1% HP or normal saline was administered into the bladder, and the evaluations were performed 2 weeks after viral inoculation. In HP-induced cystitis rats, gene delivery of PL or PP1α decreased pain behavior as well as a reduction in the intercontraction interval. Also, both treatments reduced nerve growth factor expression in the bladder mucosa, reduced bladder inflammation characterized by infiltration of inflammatory cells and increased bladder weight. Taken together, HSV-mediated gene therapy targeting TRPV1 receptors could be effective for the treatment of IC/BPS.

Urothelial Tight Junction Barrier Dysfunction Sensitizes Bladder Afferents

Interstitial cystitis/bladder pain syndrome (IC/BPS) is a chronic voiding disorder that presents with pain in the urinary bladder and surrounding pelvic region. A growing body of evidence suggests that an increase in the permeability of the urothelium, the epithelial barrier that lines the interior of the bladder, contributes to the symptoms of IC/BPS. To examine the consequence of increased urothelial permeability on pelvic pain and afferent excitability, we overexpressed in the urothelium claudin 2 (Cldn2), a tight junction (TJ)-associated protein whose message is significantly upregulated in biopsies of IC/BPS patients. Consistent with the presence of bladder-derived pain, rats overexpressing Cldn2 showed hypersensitivity to von Frey filaments applied to the pelvic region. Overexpression of Cldn2 increased the expression of c-Fos and promoted the activation of ERK1/2 in spinal cord segments receiving bladder input, which we conceive is the result of noxious stimulation of afferent pathways. To determine whether the mechanical allodynia observed in rats with reduced urothelial barrier function results from altered afferent activity, we examined the firing of acutely isolated bladder sensory neurons. In patch-clamp recordings, about 30% of the bladder sensory neurons from rats transduced with Cldn2, but not controls transduced with GFP, displayed spontaneous activity. Furthermore, bladder sensory neurons with tetrodotoxin-sensitive (TTX-S) action potentials from rats transduced with Cldn2 showed hyperexcitability in response to suprathreshold electrical stimulation. These findings suggest that as a result of a leaky urothelium, the diffusion of urinary solutes through the urothelial barrier sensitizes bladders afferents, promoting voiding at low filling volumes and pain.

Effect of Intravesical Liposome-Based Nerve Growth Factor Antisense Therapy on Bladder Overactivity and Nociception in a Rat Model of Cystitis Induced by Hydrogen Peroxide

The aim of this study was to evaluate whether liposome-based local suppression of nerve growth factor (NGF) in the bladder has effects on bladder hypersensitivity in a rat cystitis model induced by intravesical instillation of hydrogen peroxide (HP). HP (1.5%) was intravesically administered to adult female Sprague-Dawley rats. Liposomes complexed with NGF antisense oligonucleotide (OND) labeled with TYE563 fluorescent tag were intravesically instilled on day 2. Red fluorescence from the TYE 563 tag was observed with fluorescent microscopy on day 3. Four separate groups of rats were used in the following experiments: (a) sham-liposome group, (b) sham-OND group, (c) cystitis-liposome group, and (d) cystitis-OND group. Saline or 1.5% HP was intravesically administered on day 0. Empty liposomes or liposomes-antisense OND were instilled into the bladder on day 2. The following experiments were conducted to evaluate the effect of NGF antisense treatment on day 7: (a) continuous cystometry was performed in an awake condition; (b) pain behavior induced by instillation of resiniferatoxin into the bladder, including licking behavior (lower abdominal licking) and freezing behavior (motionless head-turning toward lower abdomen), was observed; (c) immunohistochemical staining of the bladder and L6 DRG for NGF was performed; (d) the expression of several genes in the bladder was analyzed by reverse transcription polymerase chain reaction (RT-PCR); and (e) after Fast Blue was injected into the bladder wall, Fast Blue-positive or -negative cells in DRG neurons were separately collected by using a laser-capture microdissection method 7 days later. RT-PCR was performed to evaluate gene expressions in captured neuronal cells. The expression of TYE563 was identified only in the urothelial layer. In cystometric investigation, intercontraction intervals (ICI) were significantly (p = 0.001) shorter in the cystitis-liposome group in comparison to the sham-liposome group. ICI was significantly (p = 0.007) longer in the cystitis-OND group compared to the cystitis-liposome group. Comparisons of the sham-liposome and the sham-OND groups showed no significant difference in ICI (p = 0.56). Licking events did not significantly differ among the four groups. In contrast, the cystitis-liposome group showed significantly more freezing events than the sham-liposome group did (p = 0.002). A significant reduction in the number of freezing events was observed in the cystitis-OND group compared to the cystitis-liposome group (p = 0.04). Immunofluorescence staining demonstrated that NGF expression in the mucosa (p = 0.02) and L6 DRG (p = 0.01) was significantly higher in the cystitis-liposome group than it was in the sham-liposome group. The expression of NGF was significantly lower in the mucosa (p = 0.002) and L6 DRG (p = 0.01) in the cystitis-OND group compared to the cystitis-liposome group. RT-PCR showed that the expression of NGF and TRPV1 mRNA in the mucosa was significantly higher in the cystitis-liposome group than it was in the sham-liposome group (p = 0.001 and 0.03, respectively). On the other hand, these gene expressions were significantly lower in the cystitis-OND group than they were in the cystitis-liposome group (p = 0.007 and 0.02, respectively). The cystitis-liposome group showed significantly higher expression of TRPA1, P2X3, and BDNF mRNA in labeled bladder afferent neurons than the sham-liposome group did (p = 0.03, 0.01, and 0.001, respectively). These gene expressions were significantly lower in the cystitis-OND group compared to the cystitis-liposome group (p = 0.04, 0.006, and 0.03, respectively). The study indicated that intravesical application of liposome-NGF antisense OND significantly improved bladder hypersensitivity induced by chemical cystitis in rats. Intravesical treatment with liposome-OND conjugates could be a novel local therapy of hypersensitive bladder disorders such as bladder pain syndrome/interstitial cystitis.

A Prospective, Multicenter, Double-Blind, Randomized Trial of Bladder Instillation of Liposome Formulation OnabotulinumtoxinA for Interstitial Cystitis/Bladder Pain Syndrome

PURPOSE

Intravesical instillation of liposomal formulated botulinum toxin A (lipotoxin) has shown therapeutic effects as treatment of refractory overactive bladder without needle injections. We assessed lipotoxin to treat refractory interstitial cystitis/bladder pain syndrome.

MATERIALS AND METHODS

This 2-center, double-blind, randomized, placebo controlled, physician initiated study enrolled patients with refractory interstitial cystitis/bladder pain syndrome. A total of 31 patients were assigned to intravesical instillation of lipotoxin (onabotulinumtoxinA 200 U with 80 mg sphingomyelin), 28 were assigned to onabotulinumtoxinA 200 U in normal saline and 31 were assigned to normal saline alone. The primary end point was the average change in O'Leary-Sant symptom scores, including ICSI (Interstitial Cystitis Symptom Index) and ICPI (Interstitial Cystitis Problem Index) between baseline and 4 weeks after treatment. Other end points included the average changes in a 3-day voiding diary, a visual analog scale for pain and a global response assessment of patient satisfaction.

RESULTS

Improvements in the pain scale and O'Leary-Sant symptom scores occurred in all 3 groups by 4 weeks after treatment. Lipotoxin instillation was associated with a statistically significant decrease in O'Leary-Sant symptom scores (mean ± SD 7.38 ± 8.75), ICSI (4.00 ± 4.28), ICPI (3.35 ± 5.11) and the visual analog scale pain scale (1.64 ± 2.52), and an increase in the global response assessment (1.35 ± 1.28). However, there was no difference in improvement among the 3 groups. No significant adverse events were found in any group.

CONCLUSIONS

Lipotoxin failed to demonstrate a positive proof of concept compared to onabotulinumtoxinA or placebo. However, a single intravesical instillation of lipotoxin was associated with decreased interstitial cystitis/bladder pain syndrome symptoms compared to baseline in patients with moderate to severe interstitial cystitis/bladder pain syndrome. The effect was likely due to a significant placebo effect.

Investigational drugs for bladder pain syndrome (BPS) / interstitial cystitis (IC)

INTRODUCTION

Bladder pain syndrome (BPS)/interstitial cystitis (IC) is associated with sensory lower urinary tract symptoms. Unfortunately, many of the existing oral treatments are ineffective in most patients of BPS/IC, which is the motivation for developing new drugs and therapeutic approaches. This review covers the latest drugs that have been investigated in BPS/IC patients. Intravesical treatments offer the opportunity to directly target the painful bladder with less systemic side effects.

AREAS COVERED

In this review, the authors analyze the existing literature supporting the treatment of BPS/IC with conventional drugs including heparin, hyaluronic acid, chondroitin sulfate, and dimethylsulfoxide (DMSO). Furthermore, investigational drugs such as tanezumab and adalimumab, capable of sequestering nerve growth factor (NGF), and Tumor necrosis factor-α (TNF- α) are discussed. Investigational treatments such as liposomes, botulinum toxin (BTX), liposomal BTX, PD-0299685 (a Ca(2+) channel ɑ2δ ligand), continuous intravesical lidocaine, and AQX-1125 (a novel SHIP1 activating compound) are also covered.

EXPERT OPINION

New investigational drugs offer promising improvements in clinical outcomes for BPS/IC patients; however, BPS/IC is a chronic pain disorder that is very vulnerable to a strong placebo effect. In addition, BPS/IC is a heterogeneous disorder that can be classified into several phenotypes. Since different phenotypes of BPS/IC respond differently to systemic and intravesical treatments, the authors believe that new drugs developed for BPS/IC are more likely to meet their predetermined clinical endpoints if the inclusion/exclusion criterion is tailored to specific phenotype of BPS/IC patients.

Mast Cell-Mediated Mechanisms of Nociception

Mast cells are tissue-resident immune cells that release immuno-modulators, chemo-attractants, vasoactive compounds, neuropeptides and growth factors in response to allergens and pathogens constituting a first line of host defense. The neuroimmune interface of immune cells modulating synaptic responses has been of increasing interest, and mast cells have been proposed as key players in orchestrating inflammation-associated pain pathobiology due to their proximity to both vasculature and nerve fibers. Molecular underpinnings of mast cell-mediated pain can be disease-specific. Understanding such mechanisms is critical for developing disease-specific targeted therapeutics to improve analgesic outcomes. We review molecular mechanisms that may contribute to nociception in a disease-specific manner.

Increased urothelial paracellular transport promotes cystitis

Changes in the urothelial barrier are observed in patients with cystitis, but whether this leads to inflammation or occurs in response to it is currently unknown. To determine whether urothelial barrier dysfunction is sufficient to promote cystitis, we employed in situ adenoviral transduction to selectively overexpress the pore-forming tight junction-associated protein claudin-2 (CLDN-2). As expected, the expression of CLDN-2 in the umbrella cells increased the permeability of the paracellular route toward ions, but not to large organic molecules. In vivo studies of bladder function revealed higher intravesical basal pressures, reduced compliance, and increased voiding frequency in rats transduced with CLDN-2 vs. controls transduced with green fluorescent protein. While the integrity of the urothelial barrier was preserved in the rats transduced with CLDN-2, we found that the expression of this protein in the umbrella cells initiated an inflammatory process in the urinary bladder characterized by edema and the presence of a lymphocytic infiltrate. Taken together, these results are consistent with the notion that urothelial barrier dysfunction may be sufficient to trigger bladder inflammation and to alter bladder function.

Herpes Simplex Virus Vector-Mediated Gene Delivery of Poreless TRPV1 Channels Reduces Bladder Overactivity and Nociception in Rats

Increased afferent excitability has been proposed as an important pathophysiology of interstitial cystitis/bladder pain syndrome (IC/BPS) and overactive bladder (OAB). In this study, we investigated whether herpes simplex virus (HSV) vectors encoding poreless TRPV1, in which the segment in C terminus of TRPV1 receptor is deleted, suppress bladder overactivity and pain behavior using a rat model of chemical cystitis. Replication-defective HSV vectors encoding poreless TRPV1 were injected into the bladder wall of adult female Sprague-Dawley rats. Additionally, recombinant HSV virus (vHG) vectors were injected as control. Cystometry (CMG) under urethane anesthesia was performed 1 week after viral injection to evaluate bladder overactivity induced by resiniferatoxin (RTx, a TRPV1 agonist). RTx-induced nociceptive behavior such as licking (lower abdominal licking) and freezing (motionless head-turning) was observed 2 weeks after viral injection. GFP expression in L4/L6/S1 dorsal root ganglia and the bladder as well as c-Fos-positive cells in the L6 spinal cord dorsal horn were also evaluated 2 weeks after viral injection. In CMG, the poreless TRPV1 vector-treated group showed a significantly smaller reduction in intercontraction intervals and voided volume after RTx infusion than the vHG-treated control group. The number of the RTx-induced freezing events was significantly decreased in the poreless TRPV1 group than in the vHG group, whereas there was no significant difference of the number of RTx-induced licking events between groups. The number of c-Fos-positive cells in the DCM and SPN regions of the L6 spinal dorsal horn was significantly smaller in the poreless TRPV1 group than in the vHG group. Our results indicated that HSV vector-mediated gene delivery of poreless TRPV1 had a therapeutic effect on TRPV1-mediated bladder overactivity and pain behavior. Thus, the HSV vector-mediated gene therapy targeting TRPV1 receptors could be a novel modality for the treatment of OAB and/or hypersensitive bladder disorders such as IC/BPS.

From bladder to systemic syndrome: concept and treatment evolution of interstitial cystitis

Interstitial cystitis, presently known as bladder pain syndrome, has been recognized for over a century but is still far from being understood. Its etiology is unknown and the syndrome probably harbors different diseases. Autoimmune dysfunction, urothelial leakage, infection, central and peripheral nervous system dysfunction, genetic disease, childhood trauma/abuse, and subsequent stress response system dysregulation might be implicated. Management is slowly evolving from a solo act by the end-organ specialist to a team approach based on new typing and phenotyping of the disease. However, oral and invasive treatments are still largely aimed at the bladder and are based on currently proposed pathophysiologic mechanisms. Future research will better define the disease, permitting individualization of treatment.

Beyond a Simple Anesthetic Effect: Lidocaine in the Diagnosis and Treatment of Interstitial Cystitis/bladder Pain Syndrome

Intravesical local anesthetics, in a wide variety of combinations, are increasingly used to treat patients with interstitial cystitis-bladder pain syndrome (IC/BPS). Lidocaine has demonstrated properties that block the neuroinflammatory cycle associated with IC/BPS at many of the interactive points in this cycle. Intravesical lidocaine has been shown to assist in identifying the bladder as the source of pain in patients with pelvic pain. An appreciation of these anti-inflammatory effects and of the pharmacokinetics of intravesical lidocaine in patients with IC/BPS could lead to a safe and effective diagnosis and treatment for an as yet unidentified subset of patients in the IC/BPS spectrum.

Development and evaluation of an E-health system to care for patients with bladder pain syndrome/interstitial cystitis

OBJECTIVES

Bladder pain syndrome/interstitial cystitis (BPS/IC) is a chronic disease that highly degrades the quality of life for patients. In the present study, Internet intervention was used to care for bladder pain syndrome/interstitial cystitis patients to alleviate their pain and bothering symptoms.

METHODS

Healthcare education was carried out through the Internet by asking the patients, who were randomly divided into study (40 patients) and control (40 patients) groups, to check possible sensitive foods, habits, and behaviors weekly to remind and consolidate important rules for promoting quality of life. The symptom flares consultation through short message service with the Internet used to elevate healthcare efficiency was undertaken. Questionnaires, including Short Form 36 health survey, O'Leary-Sant symptom and problem indices, as well as visual analog scales pain and urgency scales, were used to evaluate quality of life and disease severity improvements before and after information and communication technology intervention. The outcome was evaluated at week 8.

RESULTS

The quality of life of both the control and study groups was significantly improved. The quality of life and visual analog scales for the patients in the study group with information and communication technology intervention showed a much greater improvement compared with the patients in the control group (P < 0.05).

CONCLUSIONS

The E-health system was shown to be effective in improving quality of life of bladder pain syndrome/interstitial cystitis patients through intervention of Internet healthcare education and short message service for the consolidation of healthy behavior and lifestyle in the 8-week follow up.

Intravesical Hyaluronic Acid and Chondroitin Sulphate Improve Symptoms and Quality of Life in Patients with Late Radiation Tissue Cystitis: An Investigative Pilot Study

Intravesical hyaluronic acid (HA) and chondroitin sulphate (CS) instillation are effective for urinary tract infections (UTIs) and bladder pain syndrome. This study aimed to evaluate the tolerability, safety and efficacy of intravesical HA and CS instillation in patients with late radiation tissue cystitis (LRTC). In this pilot study, tolerability was reported as discontinuation or deviation of the protocol, safety as general or local side effects, efficacy as improvement of bladder capacity and frequency, quality of life (QoL) through the European Quality of Life 5-Dimensions (EQ-5D) (details at http://www.controlled-trials.com/ISRCTN37534393 ). Thirty-two patients with LRTC were enrolled. Twenty-seven patients (84.8%) received a mean of 12.2±0.3 months of instillation therapy. Only two patients (6.2%) developed a urinary tract infection from instillation, which required antibiotic treatment, nevertheless not compromising the therapy schedule. No male patient developed a urethral stricture. Intravesical instillation was associated with a significant increase (>50%) of bladder capacity from baseline (66.9ml) both at 3 months (101.9ml; p<0.001) and 12 months (174.4 ml; p<0.001). EQ-5D index significantly increased from baseline to both 3 and 12 months (0.26, 0.69 and 0.96, respectively; p<0.001). Intravesical co-administration of HA and CS improved bladder function, symptoms and QoL in patients with LRTC.

Intravesical resiniferatoxin for the treatment of storage lower urinary tract symptoms in patients with either interstitial cystitis or detrusor overactivity: a meta-analysis

Background

While Resin­iferatoxin (RTX) has been widely used for patients with storage lower urinary tract symptoms (LUTS), its clinical efficiency hasn't yet been well evaluated. A meta-analysis was performed to evaluate the exact roles of intravesical RTX for the treatment of storage LUTS in patients with either interstitial cystitis (IC) or detrusor overactivity (DO).

Methods

A meta-analysis of RTX treatment was performed through a comprehensive search of the literature. In total, 2,332 records were initially recruited, 1,907 from Elsevier, 207 from Medline and 218 from the Web of Science. No records were retrieved from the Embase or Cochrane Library. Seven trials with 355 patients were included and one trial was excluded because of the lack of extractable data. The analyses were all performed using RevMan 5.1 and MIX 2.0.

Results

Bladder pain was significantly reduced after RTX therapy in patients with either IC or DO. The average decrease of the visual an alogue pain scale was 0.42 after RTX treatment (p = 0.02). The maximum cystometric capacity (MCC) was significantly increased in patients with DO (MCC increase, 53.36 ml, p = 0.006) but not in those with IC (MCC increase, −19.1 ml, p = 0.35). No significant improvement in urinary frequency, nocturia, incontinence or the first involuntary detrusor contraction (FDC) was noted after RTX therapy (p = 0.06, p = 0.52, p = 0.19 and p = 0.41, respectively).

Conclusions

RTX could significantly reduce bladder pain in patients with either IC or DO, and increase MCC in patients with DO; however, no significant improvement was observed in frequency, nocturia, incontinence or FDC. Given the limitations in the small patient size and risk of bias in the included trials, great caution should be taken when intravesical RTX is used before a large, multicenter, well-designed random control trial with a long-term follow-up is carried out to further assess the clinical efficacy of RTX in in patients with storage LUTS.

Surface-modified nanoparticles enhance transurothelial penetration and delivery of survivin siRNA in treating bladder cancer

Penetration of the bladder permeability barrier (BPB) is a major challenge when treating bladder diseases via intravesical delivery. To increase transurothelial migration and tissue and tumor cell uptake, poly(lactic-co-glycolic acid; PLGA) nanoparticles (NP) were modified by addition of a low molecular weight (2.5 or 20 kDa) positively charged mucoadhesive polysaccharide, chitosan, to the NP surface. In designing these NPs, we balanced the adhesive properties of chitosan with the release and bioactivity of the siRNA. Chitosan-functionalized NPs demonstrated increased binding to and uptake in intravesically instilled mouse bladders and human ureter at 10 times the level of unmodified NPs. Furthermore, we extended the bioactivity of survivin siRNA in vitro for up to 9 days and demonstrated a decrease in proliferation when using chitosan-modified NPs relative to unmodified NPs. In addition, treatment of xenograft tumors with chitosan-modified NPs that encapsulate survivin siRNA (NP-siSUR-CH2.5) resulted in a 65% reduction in tumor volume and a 75% decrease in survivin expression relative to tumors treated with blank chitosan NPs (NP-Bk-CH2.5). Our low molecular weight chitosan delivery system has the capacity to transport large amounts of siRNA across the urothelium and/or to the tumor site, thus increasing therapeutic response.

Uroplakin peptide-specific autoimmunity initiates interstitial cystitis/painful bladder syndrome in mice

The pathophysiology of interstitial cystitis/painful bladder syndrome (IC/PBS) is enigmatic. Autoimmunity and impaired urothelium might lead the underlying pathology. A major shortcoming in IC/PBS research has been the lack of an appropriate animal model. In this study, we show that the bladder specific uroplakin 3A-derived immunogenic peptide UPK3A 65–84, which contains the binding motif for IA^d MHC class II molecules expressed in BALB/c mice, is capable of inducing experimental autoimmune cystitis in female mice of that strain. A highly antigen-specific recall proliferative response of lymph node cells to UPK3A 65–84 was observed, characterized by selectively activated CD4+ T cells with a proinflammatory Th1-like phenotype, including enhanced production of interferon γ and interleukin-2. T cell infiltration of the bladder and bladder-specific increased gene expression of inflammatory cytokines were observed. Either active immunization with UPK3A 65–84 or adoptive transfer of peptide-activated CD4+ T cells induced all of the predominant IC/PBS phenotypic characteristics, including increased micturition frequency, decreased urine output per micturition, and increased pelvic pain responses to stimulation with von Frey filaments. Our study demonstrates the creation of a more specific experimental autoimmune cystitis model that is the first inducible model for IC/PBS that manifests all of the major symptoms of this debilitating condition.

Anti-oxidant activity and attenuation of bladder hyperactivity by the flavonoid compound kaempferol

OBJECTIVES

To evaluate the anti-oxidant activity of the flavonoid compound, kaempferol, and to examine its role in the suppression of oxidative stress and attenuation of bladder hyperactivity in a rat model of bladder injury.

METHODS

The anti-oxidative activity of kaempferol was examined in lipopolysaccharide-treated RAW264.7 macrophages by using flow cytometry. For in vivo studies, rats were pretreated with kaempferol or vehicle for 24 h. The rat urothelium was injured by the administration of protamine sulfate for 1.5 h and irritated by the subsequent infusion of potassium chloride for 4 h. Oxidative stress in the bladder tissue was assessed using chemiluminescence assay, and the bladder pressure was determination by cystomertrogram.

RESULTS

Kaempferol significantly suppressed lipopolysaccharide-induced reactive oxygen species production in RAW264.7 rat macrophages. Exposure of the rat bladder to sequential infusion of protamine sulfate and potassium chloride induced bladder hyperactivity. Pretreatment with kaempferol, prevented the formation of reactive oxygen species and prolonged the intercontraction interval.

CONCLUSION

Kaempferol suppresses oxidative stress and attenuates bladder hyperactivity caused by potassium chloride after protamine sulfate-induced bladder injury.

A synthetic form of frizzled 8-associated antiproliferative factor enhances p53 stability through USP2a and MDM2

Frizzled 8-associated Antiproliferative Factor (APF) is a sialoglycopeptide urinary biomarker of interstitial cystitis/painful bladder syndrome (IC/PBS), a chronic condition of unknown etiology with variable symptoms that generally include pelvic and/or perineal pain, urinary frequency, and urgency. We previously reported that native human APF suppresses the proliferation of normal bladder epithelial cells through a mechanism that involves increased levels of p53. The goal of this study was to delineate the regulatory mechanism whereby p53 expression is regulated by APF. Two APF-responsive cell lines (T24 bladder carcinoma cells and the immortalized human bladder epithelial cell line, TRT-HU1) were treated with asialo-APF (as-APF), a chemically synthesized form of APF. Biochemical analysis revealed that as-APF increased p53 levels in two ways: by decreasing ubiquitin specific protease 2a (USP2a) expression leading to enhanced ubiquitination of murine double minute 2 E3 ubiquitin ligase (MDM2), and by suppressing association of p53 with MDM2, thus impairing p53 ubiquitination. Biological responses to as-APF were suppressed by increased expression of wild type, but not mutant USP2a, which enhanced cell growth via upregulation of a cell cycle mediator, cyclin D1, at both transcription and protein levels. Consistent with this, gene silencing of USP2a with siRNA arrested cell proliferation. Our findings suggest that APF upregulates cellular p53 levels via functional attenuation of the USP2a-MDM2 pathway, resulting in p53 accumulation and growth arrest. These data also imply that targeting USP2a, MDM2, p53 and/or complex formation by these molecules may be relevant in the development of novel therapeutic approaches to IC/PBS.

Overlap between functional GI disorders and other functional syndromes: what are the underlying mechanisms?

BACKGROUND

Irritable bowel syndrome and other gastrointestinal (GI) and non-GI disorders such as functional dyspepsia, fibromyalgia, temporomandibular joint disorder, interstitial cystitis/painful bladder syndrome, and chronic fatigue syndrome are known as functional pain syndromes. They commonly coexist within the same individual. The pathophysiologic mechanisms of these disorders are not well understood, but it has been hypothesized that they share a common pathogenesis.

PURPOSE

The objective of this review is to discuss the proposed pathophysiologic mechanisms, which have been similarly studied in these conditions. These mechanisms include enhanced pain perception, altered regional brain activation, infectious etiologies, dysregulations in immune and neuroendocrine function, and genetic susceptibility. Studies suggest that these functional disorders are multifactorial, but factors which increase the vulnerability of developing these conditions are shared.

Integration analysis of quantitative proteomics and transcriptomics data identifies potential targets of frizzled-8 protein-related antiproliferative factor in vivo

What's known on the subject? and What does the study add? Interstitial cystitis (IC) is a prevalent and debilitating pelvic disorder generally accompanied by chronic pain combined with chronic urinating problems. Over one million Americans are affected, especially middle-aged women. However, its aetiology or mechanism remains unclear. No efficient drug has been provided to patients. Several urinary biomarker candidates have been identified for IC; among the most promising is antiproliferative factor (APF), whose biological activity is detectable in urine specimens from >94% of patients with both ulcerative and non-ulcerative IC. The present study identified several important mediators of the effect of APF on bladder cell physiology, suggesting several candidate drug targets against IC. In an attempt to identify potential proteins and genes regulated by APF in vivo, and to possibly expand the APF-regulated network identified by stable isotope labelling by amino acids in cell culture (SILAC), we performed an integration analysis of our own SILAC data and the microarray data of Gamper et al. (2009) BMC Genomics 10: 199. Notably, two of the proteins (i.e. MAPKSP1 and GSPT1) that are down-regulated by APF are involved in the activation of mTORC1, suggesting that the mammalian target of rapamycin (mTOR) pathway is potentially a critical pathway regulated by APF in vivo. Several components of the mTOR pathway are currently being studied as potential therapeutic targets in other diseases. Our analysis suggests that this pathway might also be relevant in the design of diagnostic tools and medications targeting IC.

OBJECTIVE

• To enhance our understanding of the interstitial cystitis urine biomarker antiproliferative factor (APF), as well as interstitial cystitis biology more generally at the systems level, we reanalyzed recently published large-scale quantitative proteomics and in vivo transcriptomics data sets using an integration analysis tool that we have developed.

MATERIALS AND METHODS

• To identify more differentially expressed genes with a lower false discovery rate from a previously published microarray data set, an integrative hypothesis-testing statistical approach was applied. • For validation experiments, expression and phosphorylation levels of select proteins were evaluated by western blotting.

RESULTS

• Integration analysis of this transcriptomics data set with our own quantitative proteomics data set identified 10 genes that are potentially regulated by APF in vivo from 4140 differentially expressed genes identified with a false discovery rate of 1%. • Of these, five (i.e. JUP, MAPKSP1, GSPT1, PTGS2/COX-2 and XPOT) were found to be prominent after network modelling of the common genes identified in the proteomics and microarray studies. • This molecular signature reflects the biological processes of cell adhesion, cell proliferation and inflammation, which is consistent with the known physiological effects of APF. • Lastly, we found the mammalian target of rapamycin pathway was down-regulated in response to APF.

CONCLUSION

• This unbiased integration analysis of in vitro quantitative proteomics data with in vivo quantitative transcriptomics data led to the identification of potential downstream mediators of the APF signal transduction pathway.

Intravesical application of lidocaine and sodium bicarbonate in the treatment of obstructive idiopathic lower urinary tract disease in cats

BACKGROUND

In human patients with interstitial cystitis, intravesical instillation of alkalinized lidocaine sometimes is associated with sustained amelioration of symptoms beyond the acute treatment phase. Interstitial cystitis shares many features in common with feline idiopathic cystitis.

OBJECTIVE

To evaluate whether intravesical instillation of alkalinized lidocaine decreases recurrence of urethral obstruction and severity of clinical signs in cats with obstructive idiopathic LUTD.

ANIMALS

Twenty-six cats with obstructive idiopathic LUTD. Twelve cats in case group (treatment with alkalinized lidocaine) and 14 control cats (treatment with placebo or standard treatment).

METHODS

Cats were randomly assigned to treatment (2 or 4 mg/kg lidocaine and sodium bicarbonate) or placebo groups (0.2 mL/kg saline solution and sodium bicarbonate). The intravesical instillation was done once a day for 3 days. Some cats underwent standard treatment only (indwelling urinary catheter for 3 days without intravesical instillations). A 2-week, 1-month, and 2-month follow-up after treatment was made using a questionnaire. The recurrence rate and amelioration scores of clinical signs were assessed and compared.

RESULTS

Recurrence of urethral obstruction was 58% (7/12) in the case group and 57% (8/14) in the control group. Amelioration scores were similar between the 2 groups.

CONCLUSION AND CLINICAL IMPORTANCE

Intravesical administration of lidocaine for up to 3 consecutive days had no apparent beneficial effect on decreasing recurrence rate and severity of clinical signs in cats with obstructive idiopathic LUTD.

Antiproliferative factor signaling and interstitial cystitis/painful bladder syndrome

A unique glycopeptide, antiproliferative factor (APF), has been suggested as a urinary biomarker and potential mediator of long-term bladder disorder Interstitial Cystitis/Painful Bladder Syndrome. There is no known cause for this disease. Several mechanistic approaches have been employed to address the underlying mechanism whereby APF regulates cellular responses in the bladder epithelium. A summary of recent literature is provided, and is focused on signal transduction pathways and networks that are responsive to APF.