Sensitivity and specificity of antiproliferative factor, heparin-binding epidermal growth factor-like growth factor, and epidermal growth factor as urine markers for interstitial cystitis

Lower Urinary Tract Inflammation and Infection: Key Microbiological and Immunological Aspects

The urinary system, primarily responsible for the filtration of blood and waste, is affected by several infectious and inflammatory conditions. Focusing on the lower tract, this review outlines the physiological and immune landscape of the urethra and bladder, addressing key immunological and microbiological aspects of important infectious/inflammatory conditions. The conditions addressed include urethritis, interstitial cystitis/bladder pain syndrome, urinary tract infections, and urosepsis. Key aspects of each condition are addressed, including epidemiology, pathophysiology, and clinical considerations. Finally, therapeutic options are outlined, highlighting gaps in the knowledge and novel therapeutic approaches.

Mendelian Disorders in an Interstitial Cystitis/Bladder Pain Syndrome Cohort

Interstitial cystitis/bladder pain syndrome (IC/BPS) is a chronic pain disorder causing symptoms of urinary frequency, urgency, and bladder discomfort or pain. Although this condition affects a large population, little is known about its etiology. Genetic analyses of whole exome sequencing are performed on 109 individuals with IC/BPS. One family has a previously reported SIX5 variant (ENST00000317578.6:c.472G>A, p.Ala158Thr), consistent with Branchiootorenal syndrome 2 (BOR2). A likely pathogenic heterozygous variant in ATP2A2 (ENST00000539276.2:c.235G>A, p.Glu79Lys) is identified in two unrelated probands, indicating possible Darier-White disease. Two private heterozygous variants are identified in ATP2C1 (ENST00000393221.4:c.2358A>T, p.Glu786Asp (VUS/Likely Pathogenic) and ENST00000393221.4:c.989C>G, p.Thr330Ser (likely pathogenic)), indicative of Hailey-Hailey Disease. Sequence kernel association test analysis finds an increased burden of rare ATP2C1 variants in the IC/BPS cases versus a control cohort (p = 0.03, OR = 6.76), though does not survive Bonferroni correction. The data suggest that some individuals with IC/BPS may have unrecognized Mendelian syndromes. Comprehensive phenotyping and genotyping aid in understanding the range of diagnoses in the population-based IC/BPS cohort. Conversely, ATP2C1, ATP2A2, and SIX5 may be candidate genes for IC/BPS. Further evaluation with larger numbers is needed. Genetically screening individuals with IC/BPS may help diagnose and treat this painful disorder due to its heterogeneous nature.

Peptidomics analysis reveals changes in small urinary peptides in patients with interstitial cystitis/bladder pain syndrome

Interstitial cystitis/bladder pain syndrome (IC/BPS) is a chronic and debilitating pain disorder of the bladder and urinary tract with poorly understood etiology. A definitive diagnosis of IC/BPS can be challenging because many symptoms are shared with other urological disorders. An analysis of urine presents an attractive and non-invasive resource for monitoring and diagnosing IC/BPS. The antiproliferative factor (APF) peptide has been previously identified in the urine of IC/BPS patients and is a proposed biomarker for the disorder. Nevertheless, other small urinary peptides have remained uninvestigated in IC/BPS primarily because protein biomarker discovery efforts employ protocols that remove small endogenous peptides. The purpose of this study is to investigate the profile of endogenous peptides in IC/BPS patient urine, with the goal of identifying putative peptide biomarkers. Here, a non-targeted peptidomics analysis of urine samples collected from IC/BPS patients were compared to urine samples from asymptomatic controls. Our results show a general increase in the abundance of urinary peptides in IC/BPS patients, which is consistent with an increase in inflammation and protease activity characteristic of this disorder. In total, 71 peptides generated from 39 different proteins were found to be significantly altered in IC/BPS. Five urinary peptides with high variable importance in projection (VIP) coefficients were found to reliably differentiate IC/BPS from healthy controls by receiver operating characteristic (ROC) analysis. In parallel, we also developed a targeted multiple reaction monitoring method to quantify the relative abundance of the APF peptide from patient urine samples. Although the APF peptide was found in moderately higher abundance in IC/BPS relative to control urine, our results show that the APF peptide was inconsistently present in urine, suggesting that its utility as a sole biomarker of IC/BPS may be limited. Overall, our results revealed new insights into the profile of urinary peptides in IC/BPS that will aid in future biomarker discovery and validation efforts.

Urinary Biomarkers in Interstitial Cystitis/Bladder Pain Syndrome and Its Impact on Therapeutic Outcome

Interstitial cystitis/bladder pain syndrome (IC/BPS) is defined as a chronic bladder disorder with suprapubic pain (pelvic pain) and pressure and/or discomfort related to bladder filling accompanied by lower urinary tract symptoms, such as urinary frequency and urgency without urinary tract infection (UTI) lasting for at least 6 weeks. IC/BPS presents significant bladder pain and frequency urgency symptoms with unknown etiology, and it is without a widely accepted standard in diagnosis. Patients’ pathological features through cystoscopy and histologic features of bladder biopsy determine the presence or absence of Hunner lesions. IC/PBS is categorized into Hunner (ulcerative) type IC/BPS (HIC/BPS) or non-Hunner (nonulcerative) type IC/BPS (NHIC/BPS). The pathophysiology of IC/BPS is composed of multiple possible factors, such as chronic inflammation, autoimmune disorders, neurogenic hyperactivity, urothelial defects, abnormal angiogenesis, oxidative stress, and exogenous urine substances, which play a crucial role in the pathophysiology of IC/BPS. Abnormal expressions of several urine and serum specimens, including growth factor, methylhistamine, glycoprotein, chemokine and cytokines, might be useful as biomarkers for IC/BPS diagnosis. Further studies to identify the key molecules in IC/BPS will help to improve the efficacy of treatment and identify biomarkers of the disease. In this review, we discuss the potential medical therapy and assessment of therapeutic outcome with urinary biomarkers for IC/BPS.

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.

A nomogram for bladder pain syndrome/interstitial cystitis based on netrin-1

Purpose

This study aimed to combine plasma netrin-1 and clinical parameters to construct a diagnostic model for bladder pain syndrome/interstitial cystitis (BPS/IC).

Methods

We analyzed the independent diagnostic value of netrin-1 and the correlation with clinical symptom scores of BPS/IC. Clinical parameters were selected using LASSO regression, and a multivariate logistic regression model based on netrin-1 was established, and then a nomogram of BPS/IC prevalence was constructed. The nomogram was evaluated using calibration curves, the C-index, and decision curve analysis (DCA). Finally, the model was validated using an internal validation method.

Results

The area under the curve for the ability of netrin-1 to independently predict BPS/IC diagnosis was 0.858 (p < 0.001), with a sensitivity of 85% and specificity of 82%. The predicted nomogram included three variables: age, CD3 + /CD4 + T lymphocyte ratio, and netrin-1. The C-index of this nomogram was 0.882, and the predicted values were highly consistent with the actual results in the calibration curve. In addition, the internally validated C-index of 0.870 confirms the high reliability of the model. DCA results show that the net patient benefit of the netrin-1 combined with other clinical parameters was higher than that of the single netrin-1 model.

Conclusion

Netrin-1 can be used as a diagnostic marker for BPS/IC and is associated with pain. The nomogram constructed by combining netrin-1 and clinical parameters was able to predict BPS/IC with great accuracy. In addition, Netrin-1 may also serve as a novel therapeutic target for BPS/IC.

Biomarkers in Interstitial Cystitis/Bladder Pain Syndrome with and without Hunner Lesion: A Review and Future Perspectives

Interstitial cystitis/bladder pain syndrome (IC/BPS) is a debilitating urinary bladder condition that presents with a wide variety of clinical phenotypes. It is commonly characterized by persistent pelvic pain and lower urinary tract symptoms, such as urinary frequency and urgency. Current clinicopathological and genomic evidence has indicated that IC/BPS with Hunner lesions is a clinically relevant distinct subtype with proven bladder pathology of subepithelial chronic inflammatory changes that are characterized by enhanced local immune responses and epithelial denudation. However, other forms of IC/BPS lacking Hunner lesions are a symptom syndrome complex of non-inflammatory conditions with little evidence of bladder etiology, characterized by aberrant neural activity in neurotransmission systems which leads to central nervous sensitization with potential involvement of urothelial malfunction, or clinical presentation of somatic and/or psychological symptoms beyond the bladder. Given such distinct potential pathophysiology between IC/BPS subtypes, disease biomarkers of IC/BPS should be provided separately for subtypes with and without Hunner lesions. Tailored approaches that target characteristic immunological inflammatory processes and epithelial denudation for IC/BPS with Hunner lesions, or the sensitized/altered nervous system, urothelial malfunction, association with other functional somatic syndromes, and psychosocial problems for IC/BPS without Hunner lesions, are essential to identify optimal and reliable disease-specific IC/BPS biomarkers.

Omics in urology: An overview on concepts, current status and future perspectives

Recent technological advances in molecular biology have led to great progress in the knowledge of structure and function of cells and their main constituents. In this setting, 'omics' is standing out in order to significantly improve the understanding of etiopathogenetic mechanisms of disease and contribute to the development of new biochemical diagnostics and therapeutic tools. 'Omics' indicates the scientific branches investigating every aspect of cell's biology, including structures, functions and dynamics pathways. The main 'omics' are genomics, epigenomics, proteomics, transcriptomics, metabolomics and radiomics. Their diffusion, success and proliferation, addressed to many research fields, has led to many important acquisitions, even in Urology. Aim of this narrative review is to define the state of art of 'omics' application in Urology, describing the most recent and relevant findings, in both oncological and non-oncological diseases, focusing the attention on urinary tract infectious, interstitial cystitis, urolithiasis, prostate cancer, bladder cancer and renal cell carcinoma. In Urology the majority of 'omics' applications regard the pathogenesis and diagnosis of the investigated diseases. In future, its role should be implemented in order to develop specific predictors and tailored treatments.

Phenotypes of BPS/IC

Purpose of Review

The aim of this review is to summarise the latest research related to different phenotypes of BPS/IC, addressing the evidence for current well-defined phenotypes as well as identifying novel potential phenotypes and highlighting areas for future study.

Recent Findings

Two distinct phenotypes of BPS/IC are well-recognised: Hunner’s lesion disease and non-Hunner’s lesion BPS/IC. Recent studies have shown these phenotypes exhibit distinct clinical, pathological and cystoscopic features, and targeted treatment to Hunner’s lesions can prove effective. Recent studies have also identified new potential phenotypes based on biochemical, molecular and histological markers, pathophysiological mechanisms of disease, clinical features, cystoscopic findings, radiological features and urodynamic factors. This evidence has improved our understanding of the underlying mechanism of disease and may enable more personalised and targeted therapy in the future.

Summary

Novel phenotypes of BPS/IC relate to the presence of certain biomarkers, alterations in the urinary microbiome, the characteristics of pain and presence of co-existing somatic and psychosocial conditions, altered patterns of brain white matter changes and urodynamic features. Further study is required to evaluate whether these potential phenotypes are clinically useful based on their ability to guide treatment selection and predict outcome from therapy, and therefore optimise therapeutic outcomes.

Metabolomics in Central Sensitivity Syndromes

Central sensitization syndromes are a collection of frequently painful disorders that contribute to decreased quality of life and increased risk of opiate abuse. Although these disorders cause significant morbidity, they frequently lack reliable diagnostic tests. As such, technologies that can identify key moieties in central sensitization disorders may contribute to the identification of novel therapeutic targets and more precise treatment options. The analysis of small molecules in biological samples through metabolomics has improved greatly and may be the technology needed to identify key moieties in difficult to diagnose diseases. In this review, we discuss the current state of metabolomics as it relates to central sensitization disorders. From initial literature review until Feb 2020, PubMed, Embase, and Scopus were searched for applicable studies. We included cohort studies, case series, and interventional studies of both adults and children affected by central sensitivity syndromes. The majority of metabolomic studies addressing a CSS found significantly altered metabolites that allowed for differentiation of CSS patients from healthy controls. Therefore, the published literature overwhelmingly supports the use of metabolomics in CSS. Further research into these altered metabolites and their respective metabolic pathways may provide more reliable and effective therapeutics for these syndromes.

Effect of twice-daily oral administration of a chondroitin sulfate-containing supplement on urine chondroitin sulfate concentrations in dogs

OBJECTIVE

To quantify the magnitude and duration of changes in urine chondroitin sulfate concentration (uCS) as a result of oral administration of a chondroitin sulfate-containing supplement in dogs.

ANIMALS

8 healthy privately owned dogs.

PROCEDURES

A urine sample was collected from each dog via cystocentesis on day 1; free-catch midstream urine samples were collected once daily on days 2 through 5. Pretreatment uCS was established from those samples. Each dog then received a chondroitin sulfate-containing supplement (20 to 30 mg/kg, PO, q 12 h) for 8 days (on days 7 through 14). Urine samples were collected on days 8 through 12 and day 15. For each sample, uCS was quantified by liquid chromatography-tandem mass spectrometry. Variable urine concentration was accounted for by dividing the uCS by urine creatinine concentration (uCrea) to determine the uCS:uCrea ratio. Pretreatment uCS:uCrea ratios were compared with treatment uCS:uCrea ratios to calculate the fold change in uCS after supplement administration.

RESULTS

Among the study dogs, oral administration of the chondroitin sulfate-containing supplement resulted in a 1.9-fold increase in the median uCS:uCrea ratio. Data obtained on days 8 through 12 and day 15 indicated that the daily increase in uCS remained consistent and was not additive.

CONCLUSIONS AND CLINICAL RELEVANCE

Results indicated that oral administration of supplemental chondroitin sulfate to dogs modestly increased uCS within 24 hours; however, subsequent supplement administration did not have an additive effect. A potential therapeutic benefit of persistently increased uCS in preventing recurrent urinary tract infections in dogs warrants investigation.

Development of an interstitial cystitis risk score for bladder permeability

BACKGROUND

Interstitial cystitis/bladder pain syndrome (IC) is a multifactorial syndrome of severe pelvic and genitalia pain and compromised urinary function; a subset of IC patients present with Hunner's lesions or ulcers on their bladder walls (UIC). UIC is diagnosed by cystoscopy, which may be quite painful. The objective of this study was to determine if a calculated Bladder Permeability Defect Risk Score (BP-RS) based on non-invasive urinary cytokines could discriminate UIC patients from controls and IC patients without Hunner's ulcers.

METHODS

A national crowdsourcing effort targeted IC patients and age-matched controls to provide urine samples. Urinary cytokine levels for GRO, IL-6, and IL-8 were determined using a Luminex assay.

RESULTS

We collected 448 urine samples from 46 states consisting of 153 IC patients (147 female, 6 male), of which 54 UIC patients (50 females, 4 male), 159 female controls, and 136 male controls. A defined BP-RS was calculated to classify UIC, or a bladder permeability defect etiology, with 89% validity.

CONCLUSIONS

The BP-RS Score quantifies UIC risk, indicative of a bladder permeability defect etiology in a subset of IC patients. The Bladder Permeability Defect Risk Score is the first validated urine biomarker assay for interstitial cystitis/bladder pain syndrome.

Implications for bidirectional signaling between afferent nerves and urothelial cells-ICI-RS 2014

AIMS

To present a synopsis of the presentations and discussions from Think Tank I, "Implications for afferent-urothelial bidirectional communication" of the 2014 International Consultation on Incontinence-Research Society (ICI-RS) meeting in Bristol, UK.

METHODS

The participants presented what is new, currently understood or still unknown on afferent-urothelial signaling mechanisms. New avenues of research and experimental methodologies that are or could be employed were presented and discussed.

RESULTS

It is clear that afferent-urothelial interactions are integral to the regulation of normal bladder function and that its disruption can have detrimental consequences. The urothelium is capable of releasing numerous signaling factors that can affect sensory neurons innervating the suburothelium. However, the understanding of how factors released from urothelial cells and afferent nerve terminals regulate one another is incomplete. Utilization of techniques such as viruses that genetically encode Ca(2+) sensors, based on calmodulin and green fluorescent protein, has helped to address the cellular mechanisms involved. Additionally, the epithelial-neuronal interactions in the urethra may also play a significant role in lower urinary tract regulation and merit further investigation.

CONCLUSION

The signaling capabilities of the urothelium and afferent nerves are well documented, yet how these signals are integrated to regulate bladder function is unclear. There is unquestionably a need for expanded methodologies to further our understanding of lower urinary tract sensory mechanisms and their contribution to various pathologies.

Study of the apoptotic effect of urine as a diagnostic biomarker in patients with interstitial cystitis

INTRODUCTION

The main objective of the study was to assess the apoptotic effect of urine from patients with interstitial cystitis (IC) in cell cultures and to study its value as a diagnostic biomarker for IC.

MATERIAL AND METHODS

A prospective study was conducted between January 2010 and January 2015 and included 57 patients diagnosed with IC and 50 healthy patients from the Hospital Clinic of Barcelona and the La Paz University Hospital. The urine of these patients was exposed to cell cultures, and its ability to induce apoptosis in the cultures was analysed. Using flow cytometry, we then measured the degree of apoptosis, quantified by the percentage of cells of the cell cycle in phase sub G0.

RESULTS

The cell cultures exposed to the urine of patients with IC had a sub G1 peak and a G2 phase, which was significantly greater than that of the control group, and a significantly lower percentage in the S phase than the control group. The mean apoptosis values in the urine cultures from patients with IC were significantly higher than those of the control group. Using a value >10% of the apoptosis test as a positive result, we observed a specificity of 96% and a positive predictive value of 92%.

CONCLUSIONS

The urine of patients with IC exerts an apoptotic effect on tumour cell cultures that is significantly greater than that exerted by the urine of healthy control patients. A≥10% cutoff for the apoptosis test presented very low sensitivity (40%) but had a very high specificity (96%), thereby able to confirm the diagnosis of IC when positive.

The Challenges of Interstitial Cystitis: Current Status and Future Prospects

Interstitial cystitis/bladder pain syndrome (IC/BPS) is a syndrome of unpleasant bladder sensations and lower urinary tract symptoms. The three main proposed etiologies are bladder urothelial dysfunction, bladder inflammation (possible neurogenic), and neuropathic pain. Despite decades of basic and clinical research, IC/BPS remains difficult to treat. A variety of treatments are used, each aimed towards one etiology. For example, glycosaminoglycans are thought to improve the urothelial permeability barrier, anti-inflammatory agents are used to decrease general inflammation, and mast cell stabilizers and/or antagonists of mast cell products are used in the treatment of neurogenic inflammation. In the (unfortunately frequent) event that a treatment fails, possible reasons are that (1) the clinician is aiming towards the wrong etiology for that patient (i.e., the treatment is off target) or (2) the correct etiology is being targeted, but the treatment is not ameliorating it (i.e., the treatment is sub-therapeutic). This is a crucial distinction, because an off-target treatment should be abandoned, but a sub-therapeutic treatment should be escalated. Currently, our inability to make this crucial distinction is the greatest obstacle to effective treatment. An important future advance would be to identify urine or serum biomarkers specific to each etiologic target. Then, each biomarker could be used to select appropriate patients for each treatment and monitor the treatment's effect on its intended target.

Sensory Hyperinnervation Distinguishes Bladder Pain Syndrome/Interstitial Cystitis from Overactive Bladder Syndrome

PURPOSE

Pain is the key symptom that distinguishes bladder pain syndrome/interstitial cystitis from overactive bladder syndrome but overlap occurs. To find a discriminating marker for these bladder diseases we examined sensory hyperinnervation and neurotrophin receptor expression in bladder biopsies as well as nerve growth factor levels in urine.

MATERIALS AND METHODS

Bladder biopsies from patients with bladder pain syndrome/interstitial cystitis, including 12 with and 19 without Hunner lesions, 13 with overactive bladder syndrome and 12 healthy controls, were analyzed by immunohistochemistry with antibodies to the nerve cell marker PGP9.5 (neuron-specific protein gene product 9.5), p75^NTR (p75 neurotrophin receptor), the B-lymphocyte marker CD20 and mast cell tryptase. Urinary nerve growth factor was quantified by enzyme-linked immunosorbent assay.

RESULTS

Subepithelial sensory hyperinnervation on PGP9.5 staining had 97% sensitivity and 76% specificity, increased lymphocytic infiltration had 90% sensitivity and 80% specificity, and urothelial defects had 97% sensitivity and 76% specificity to distinguish bladder pain syndrome/interstitial cystitis with and without Hunner lesions from overactive bladder syndrome and healthy controls. Increased sensory innervation was associated with submucosal mast cell localization. Staining of p75^NTR in basal urothelial cells was indicative of bladder pain syndrome/interstitial cystitis. Urinary nerve growth factor levels were below the detection level and did not differentiate bladder diseases from healthy controls.

CONCLUSIONS

Sensory hyperinnervation and basal urothelial p75^NTR staining together with assessment of inflammatory lymphocytes and urothelial integrity allow for the differentiation of bladder pain syndrome/interstitial cystitis and overactive bladder syndrome even in the absence of Hunner lesions. Furthermore, these histopathological criteria enable the identification of early disease stages or oligosymptomatic/asymptomatic cases and may permit timely treatment to prevent disease progress.

Familiality analysis of provoked vestibulodynia treated by vestibulectomy supports genetic predisposition

BACKGROUND

Provoked vestibulodynia is a poorly understood disease that affects 8-15% of women in their lifetime. There is significant inflammation and nerve growth in vestibular biopsies from affected women treated by vestibulectomy compared with matched female population controls without vestibulodynia. The triggers leading to this neurogenic inflammation are unknown, but they are likely multifactorial.

OBJECTIVE

Our objective was to determine whether vestibulodynia is more common in close and distantly related female relatives of women diagnosed with the disease and those specifically treated by vestibulectomy. Excess familial clustering would support a potential genetic predisposition for vestibulodynia and warrant further studies to isolate risk alleles.

STUDY DESIGN

Using population-based genealogy linked to University of Utah Hospital CPT coded data, we estimated the relative risk of vestibulectomy in female relatives of affected women. We also compared the average pairwise relatedness of cases to the expected relatedness of the population and identified high-disease-burden pedigrees.

RESULTS

A total of 183 potential vestibulectomy probands were identified using CPT codes. The relative risk of vestibulectomy was elevated in first-degree (20 [6.6-47], P < .00001), second-degree (4.5 [0.5-16], P = .07), and third-degree female relatives (3.4 [1.2-8.8], P = .03). Seventy of these 183 CPT-based probands had available clinical history to confirm a diagnosis of moderate to severe vestibulodynia. Notably, this smaller group of confirmed probands (n = 70) revealed a similar familiality in first-degree (54 [17.5-126], P < .00001), second-degree (19.7 [2.4-71], P = .005), and third-degree relatives (12 [3.3-31], P = .0004), despite less statistical power for analysis. Overall, the average pairwise relatedness of affected women was significantly higher than expected (P < .001) and a number of high-disease-burden Utah families were identified.

CONCLUSION

Our data suggest that vestibulodynia treated by vestibulectomy has a genetic predisposition. Future studies will identify candidate genes by linkage analysis in affected families and sequencing of distantly related probands.

Abnormal Akt signalling in bladder epithelial cell explants from patients with interstitial cystitis/bladder pain syndrome can be induced by antiproliferative factor treatment of normal bladder cells

OBJECTIVES

To determine whether protein kinase B (Akt) signalling and secretion of specific downstream effector proteins are abnormal in specific cell fractions of bladder epithelial cells from patients with interstitial cystitis/bladder pain syndrome (IC/BPS), as explanted bladder epithelial cells from patients with IC/BPS produce a frizzled 8-related glycopeptide antiproliferative factor (APF) that inhibits normal bladder epithelial cell proliferation and expression of several proteins known to be regulated by Akt signalling. A related secondary objective was to determine whether treatment of normal bladder epithelial cells with active synthetic asialo-antiproliferative factor (as-APF) induces similar changes in Akt signalling and specific downstream effector proteins/mRNAs.

PATIENTS AND METHODS

Cell proteins were extracted into four subcellular fractions from primary bladder epithelial explants of six patients who fulfilled modified National Institute of Diabetes and Digestive and Kidney Diseases (NIDDK) criteria for IC/BPS and six age- and gender-matched controls. Total and/or phosphorylated cellular Akt, glycogen synthase kinase 3β (GSK3β), and β-catenin; total cellular JunB; and secreted matrix metalloproteinase 2 (MMP2) and heparin-binding epidermal growth factor-like growth factor (HB-EGF) levels were determined by Western blot. MMP2, JunB, p53, uroplakin 3 (UPK3), and β-actin mRNAs were quantified by quantitative reverse transcriptase-polymerase chain reaction. Akt activity was determined by nonradioactive assay.

RESULTS

IC/BPS cells had lower Akt activity, along with lower Akt ser473- and GSK3β ser9-phosphorylation and higher β-catenin ser33,37/thr41-phosphorylation in specific fractions as compared with matched control cells. IC/BPS explants also had evidence of additional downstream abnormalities compared with control cells, including lower nuclear JunB; lower secreted MMP2 and HB-EGF; plus lower MMP2, JunB, and UPK3 mRNAs but higher p53 mRNA relative to β-actin. Each of these IC/BPS cell abnormalities was also induced in normal cells by as-APF.

CONCLUSION

These findings indicate that IC/BPS cells have abnormal Akt activity with downstream protein expression abnormalities including decreased MMP2 and HB-EGF secretion. They also support the hypothesis that APF plays a role in the pathogenesis of IC/BPS via its effects on cell Akt signalling and HB-EGF production.

Detection of inflammatory biomarkers in saliva and urine: Potential in diagnosis, prevention, and treatment for chronic diseases

Inflammation is a part of the complex biological response of inflammatory cells to harmful stimuli, such as pathogens, irritants, or damaged cells. This inflammation has been linked to several chronic diseases including cancer, atherosclerosis, rheumatoid arthritis, and multiple sclerosis. Major biomarkers of inflammation include tumor necrosis factor, interleukins (IL)-1, IL-6, IL-8, chemokines, cyclooxygenase, 5-lipooxygenase, and C-reactive protein, all of which are regulated by the transcription factor nuclear factor-kappaB. Although examining inflammatory biomarkers in blood is a standard practice, its identification in saliva and/or urine is more convenient and non-invasive. In this review, we aim to (1) discuss the detection of these inflammatory biomarkers in urine and saliva; (2) advantages of using salivary and urinary inflammatory biomarkers over blood, while also weighing on the challenges and/or limitations of their use; (3) examine their role(s) in connection with diagnosis, prevention, treatment, and drug development for several chronic diseases with inflammatory consequences, including cancer; and (4) explore the use of innovative salivary and urine based biosensor strategies that may permit the testing of biomarkers quickly, reliably, and cost-effectively, in a decentralized setting.

Potential urine and serum biomarkers for patients with bladder pain syndrome/interstitial cystitis

There is a lack of consensus on the pathophysiology of bladder pain syndrome/interstitial cystitis. The chronic pain symptoms of bladder pain syndrome/interstitial cystitis refractory to local treatment could be a result of central nervous system sensitization and persisting abnormalities in the bladder wall, which activate the afferent sensory system. Evidence also shows that bladder pain syndrome/interstitial cystitis is a heterogeneous syndrome and that the two subtypes, the ulcerative (classic) and non-ulcerative types, represent different disease entities. There is a need for non-invasive markers for the differential diagnoses of the subtypes of bladder pain syndrome/interstitial cystitis, and between bladder pain syndrome/interstitial cystitis and bladder sensory disorders, such as hypersensitive bladder syndrome or overactive bladder. Bladder pain syndrome/interstitial cystitis, but not overactive bladder, involves an aberrant differentiation program in the bladder urothelium that leads to altered synthesis of several proteoglycans, cell adhesion and tight junction proteins, and bacterial defense molecules. These findings have led to the rationale for identifying urinary biomarkers to detect bladder pain syndrome/interstitial cystitis in patients with frequency urgency syndrome. Recently, the markers that have been the focus of the most research are antiproliferative factor, epidermal growth factor, heparin-binding epidermal growth factor, glycosaminoglycans and bladder nitric oxide. In addition, inflammatory proteins in the urine and serum play important roles in the pathogenesis of bladder pain syndrome/interstitial cystitis. The urinary proteome is an easily accessible source of biomarkers for differentiation between inflammatory bladder disorders. Analysis of multiple urinary proteins and serum cytokines could provide a diagnostic basis for bladder pain syndrome/interstitial cystitis, and could be a tool for the differential diagnosis of bladder pain syndrome/interstitial cystitis and other sensory bladder disorders.

NGF and HB-EGF: potential biomarkers that reflect the effects of fesoterodine in patients with overactive bladder syndrome

PURPOSE

To determine whether levels of nerve growth factor (NGF) and heparin-binding epidermal growth factor-like growth factor (HB-EGF) can be used to objectively assess overactive bladder syndrome (OAB) treatment outcome and to evaluate the effects of fixed-dose fesoterodine on OAB symptoms.

MATERIALS AND METHODS

This study included 124 participants (62 patients with OAB and 62 controls) in Severance Hospital between 2010 and 2012. In patients with OAB, 4 mg fesoterodine was administered once daily. Repeated evaluations of putative biomarker levels, urine creatinine (Cr) levels, and questionnaire responses, including the Overactive Bladder Symptom Score (OABSS) and the Overactive Bladder Questionnaire (OAB q), were performed from baseline to 16 weeks.

RESULTS

Urinary levels of NGF/Cr (OAB: 1.13±0.9 pg/mg; control: 0.5±0.29 pg/mg) and HB-EGF/Cr (OAB: 8.73±6.55 pg/mg; control: 4.45±2.93 pg/mg) were significantly higher in subjects with OAB than in controls (p<0.001). After 16 weeks of fixed-dose fesoterodine treatment, urinary NGF/Cr levels (baseline: 1.13±0.08 pg/mg; 16 weeks: 0.60±0.4 pg/mg; p=0.02) and HB-EGF/Cr levels significantly decreased (baseline: 8.73±6.55 pg/mg; 16 weeks: 4.72±2.69 pg/mg; p=0.03, respectively). Both the OABSS and OAB q scores improved (p<0.001). However, there were no a statistically significant correlations between these urinary markers and symptomatic scores.

CONCLUSION

Urinary levels of NGF and HB-EGF may be potential biomarkers for evaluating outcome of OAB treatment. Fixed-dose fesoterodine improved OAB symptoms. Future studies are needed to further examine the significance of urinary NGF and HB-EGF levels as therapeutic markers for OAB.

Long-term ketamine abuse induces cystitis in rats by impairing the bladder epithelial barrier

Long-term ketamine abuse is known to affect the lower urinary tract and produce symptoms of cystitis. However, the pathophysiology and causative mechanism of the changes in bladder function remain unclear. The present study aimed to investigate the existence of ketamine-induced cystitis in a rat model and characterize the underlining mechanisms. Rats were assigned to blank control, normal saline (NS), low-dose ketamine (LK, 5 mg/kg), and high-dose ketamine (HK, 50 mg/kg) groups. The two experimental groups received ketamine hydrochloride daily for 16 weeks. All rats were housed individually for assessment of urinary frequency and urine volume. Urinary biomarkers were measured at different time points. Rat bladders were excised for histopathology, immunohistochemistry, and western blot analysis. Ketamine-treated rats had increased urinary frequency compared to NS-treated rats at Week 16. Urinary nitric oxide and antiproliferative factor levels were increased in ketamine-treated rats within the first 30 h after administration. After long-term ketamine administration, urinary glycoprotein GP51 and potassium levels were decreased in the HK and LK groups compared to the NS group. Ketamine-treated rats showed thickened bladder epithelial layer, increased expression of inducible nitric oxide synthase and occludin, and decreased expression of zonula occludens-1 in the bladder wall. Ketamine, or its urinary metabolites, disrupted the proliferation of bladder epithelial cells, resulting in defected bladder epithelial barrier. Subsequent leakage of urinary potassium causes a stress response in the bladder and provokes cystitis.

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

AIMS

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

RESULTS AND CONCLUSIONS

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

Urinary bladder, cystitis and nerve/urothelial interactions

A hallmark of functional pain syndromes, such as bladder pain syndrome/interstitial cystitis (BPS/IC) is pain in the absence of demonstrable infection or pathology of the viscera or associated nerves. There are no clear definitions of this syndrome, no proven etiologies and no effective treatments able to eradicate the symptoms. This condition is characterized by suprapubic pain, associated with bladder filling and can also be accompanied by a persistent strong desire to void, increased frequency of urination and nocturia. Severe cases of this disorder, which affects primarily women, can have considerable impact on the quality of life of patients due to extreme pain and urinary frequency, which are often difficult to treat. In addition, BPS/IC patients may also suffer co-morbid conditions where pain is a common symptom (such as irritable bowel syndrome, fibromyalgia). Theories explaining the pathology of bladder pain syndrome are many and include an altered bladder lining and possible contribution of a bacterial agent.

Urothelial signaling

The urothelium, which lines the inner surface of the renal pelvis, the ureters, and the urinary bladder, not only forms a high-resistance barrier to ion, solute and water flux, and pathogens, but also functions as an integral part of a sensory web which receives, amplifies, and transmits information about its external milieu. Urothelial cells have the ability to sense changes in their extracellular environment, and respond to chemical, mechanical and thermal stimuli by releasing various factors such as ATP, nitric oxide, and acetylcholine. They express a variety of receptors and ion channels, including P2X3 purinergic receptors, nicotinic and muscarinic receptors, and TRP channels, which all have been implicated in urothelial-neuronal interactions, and involved in signals that via components in the underlying lamina propria, such as interstitial cells, can be amplified and conveyed to nerves, detrusor muscle cells, and ultimately the central nervous system. The specialized anatomy of the urothelium and underlying structures, and the possible communication mechanisms from urothelial cells to various cell types within the bladder wall are described. Changes in the urothelium/lamina propria ("mucosa") produced by different bladder disorders are discussed, as well as the mucosa as a target for therapeutic interventions.

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.

Pharmacotherapy of interstitial cystitis in women

Interstitial cystitis is a condition that affects the urinary bladder and may be more prevalent than commonly thought. Symptoms range widely in severity and typically include urinary urgency, frequency and pelvic pain. Therapies usually target the known pathophysiology of this condition. Oral agents commonly include bladder surface mucin analogues, antihistamines, narcotics, tricyclic antidepressants and anticonvulsants. Intravesical therapy is usually used as second-line treatment. Multiple forms of pharmacotherapy are often provided simultaneously to improve efficacy and time to response.

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.

A mouse model for interstitial cystitis/painful bladder syndrome based on APF inhibition of bladder epithelial repair: a pilot study

BACKGROUND

Interstitial cystitis/painful bladder syndrome (IC/PBS) is a chronic bladder disorder with bladder epithelial thinning or ulceration, pain, urinary frequency and urgency. There is no reliably effective therapy for IC/PBS, and no generally accepted animal model for the disorder in which potential therapies can be tested. Bladder epithelial cells from IC/PBS patients make a small glycopeptide antiproliferative factor or "APF" that inhibits proliferation, decreases tight junction protein expression, increases paracellular permeability, and induces changes in gene expression of bladder epithelial cells in vitro that mimic abnormalities in IC/PBS patient biopsy specimens in vivo. We therefore determined the ability of a synthetic APF derivative to inhibit bladder epithelial repair in mice.

METHODS

The bladder epithelium of female CBA/J mice was stripped by transurethral infusion of 3% acetic acid, and mice were subsequently treated daily with one of three intravesical treatments [synthetic as-APF, inactive unglycosylated control peptide, or phosphate buffered saline carrier (PBS)] for 1-21 days. Fixed bladder sections were either stained with haematoxylin and eosin for determination of epithelial area by image analysis, or incubated with anti-uroplakin III (UPIII) or anti-zonula occludens type 1 (ZO-1) antibodies for immunofluorescence microscopy. Epithelial measurement data were analyzed by a two-way analysis of variance (ANOVA); post hoc comparisons of multiple groups were carried out using the Tukey-Kramer method.

RESULTS

Bladder epithelial repair was significantly attenuated in as-APF-treated mice as compared to control mice on days 3-21 (p < 0.05); the mean epithelial/total area over all measured days was also significantly lower in as-APF-treated mice vs. mice in either control group by post hoc analysis (p < 0.0001 for both comparisons). UPIII and ZO-1 expression was also decreased in as-APF-treated mice as compared to mice in either control group by day 7 (UPIII) or day 14 (ZO-1).

CONCLUSIONS

This model demonstrates in vivo effects of as-APF which abrogates bladder epithelial repair and expression of UPIII and ZO-1 in CBA/J mice following transurethral acetic acid infusion. As bladder epithelial thinning, decreased UPIII expression, and decreased ZO-1 expression are histopathologic features of IC/PBS patient biopsies, this model may be useful for studying the pathophysiology of IC/PBS and the effect of potential therapies.

Antiproliferative factor regulates connective tissue growth factor (CTGF/CCN2) expression in T24 bladder carcinoma cells

Connective tissue growth factor (CTGF/CNN2) is a novel APF target gene. A novel mechanism is described by which the APF cellular receptor, cytoskeleton-associated protein 4 (CKAP4), mediates APF-induced CTGF transcription.

Antiproliferative factor (APF) is a sialoglycopeptide elevated in the urine of patients with interstitial cystitis (IC)—a chronic, painful bladder disease of unknown etiology. APF inhibits the proliferation of normal bladder epithelial and T24 bladder carcinoma cells in vitro by binding to cytoskeleton-associated protein 4 (CKAP4) and altering the transcription of genes involved in proliferation, cellular adhesion, and tumorigenesis; however, specific molecular mechanisms and effector genes that control APF's antiproliferative effects are unknown. In this study, we found that there was a 7.5-fold up-regulation of connective tissue growth factor (CTGF/CCN2) expression in T24 bladder carcinoma cells treated with APF. Western blot revealed a dose-dependent increase in CCN2 protein levels, with secretion into the culture medium after APF treatment. CCN2 overexpression enhanced APF's antiproliferative activity, whereas CCN2 knockdown diminished APF-induced p53 expression. Using a luciferase reporter construct, we found that APF treatment resulted in fivefold activation of the CCN2 proximal promoter and, of importance, that small interfering RNA–mediated knockdown of CKAP4 inhibited CCN2 upregulation. In addition, we demonstrate that CKAP4 translocates to the nucleus and binds to the CCN2 proximal promoter in an APF-dependent manner, providing evidence that CCN2 regulation by APF involves CKAP4 nuclear translocation and binding to the CCN2 promoter.

Impact of intravesical hyaluronic acid and chondroitin sulfate on bladder pain syndrome/interstitial cystitis

INTRODUCTION AND HYPOTHESIS

Intravesical instillations of hyaluronic acid (HA) and chondroitin sulfate (CS) may lead to regeneration of the damaged glycosaminoglycan layer in interstitial cystitis/bladder pain syndrome (IC/BPS).

METHODS

Twenty-two patients with IC/BPS received intravesical instillations (40 ml) of sodium HA 1.6% and CS 2.0% in 0.9% saline solution (IALURIL, IBSA) once weekly for 8 weeks, then once every 2 weeks for the next 6 months.

RESULTS

The score for urgency was reduced from 6.5 to 3.6 (p = 0.0001), with a reduction in pain scores from an average of 5.6 to 3.2 (p = 0.0001). The average urine volume increased from 129.7 to 162 ml (p < 0.0001), with a reduction in the number of voids in 24 h, from 14 to 11.6 (p < 0.0001). The IC Symptom and Problem Index decreased from 25.7 to 20.3 (p < 0.0001), and the Pain Urgency Frequency score, from 18.7 to 12.8 (p < 0.0001).

CONCLUSION

The treatment appeared to be effective and well tolerated in IC/BPS in this initial experience.

Interstitial cystitis

Questions from patients about analgesic pharmacotherapy and responses from authors are presented to help educate patients and make them more effective self-advocates. The topic addressed in this issue is interstitial cystitis and a discussion on pathology, genetics, course of disease, symptoms, and treatments.

Urinary proteomics evaluation in interstitial cystitis/painful bladder syndrome: a pilot study

PURPOSE

Interstitial cystitis/painful bladder syndrome (IC/PBS) is characterized by chronic pain, pressure and discomfort felt in the pelvis or bladder. An in-depth shotgun proteomics study was carried out to profile the urinary proteome of women with IC/PBS to identify possible specific proteins and networks associated with IC%PBS.

MATERIALS AND METHODS

Urine samples from ten female IC/PBS patients and ten female asymptomatic, healthy control subjects were analyzed in quadruplicate by liquid chromatography-tandem mass spectrometry (LC-MS/MS) on a hybrid linear ion trap-orbitrap mass spectrometer. Gas-phase fractionation (GPF) was used to enhance protein identification. Differences in protein quantity were determined by peptide spectral counting.

RESULTS

alpha-1B-glycoprotein (A1BG) and orosomucoid-1 (ORM1) were detected in all IC%PBS patients, and > or = 60% of these patients had elevated expression of these two proteins compared to control subjects. Transthyretin (TTR) and hemopexin (HPX) were detected in all control individuals, but > or = 60% of the IC/PBS patients had decreased expression levels of these two proteins. Enrichment functional analysis showed cell adhesion and response to stimuli were down-regulated whereas response to inflammation, wounding, and tissue degradation were up-regulated in IC/PBS. Activation of neurophysiological processes in synaptic inhibition, and lack of DNA damage repair may also be key components of IC%PBS.

CONCLUSION

There are qualitative and quantitative differences between the urinary proteomes of women with and without IC%PBS. We identified a number of proteins as well as pathways%networks that might contribute to the pathology of IC%PBS or result from perturbations induced by this condition.

Normalization of proliferation and tight junction formation in bladder epithelial cells from patients with interstitial cystitis/painful bladder syndrome by d-proline and d-pipecolic acid derivatives of antiproliferative factor

Interstitial cystitis/painful bladder syndrome is a chronic bladder disorder with epithelial thinning or ulceration, pain, urinary frequency and urgency, for which there is no reliably effective therapy. We previously reported that interstitial cystitis/painful bladder syndrome bladder epithelial cells make a glycopeptide antiproliferative factor or 'APF' (Neu5Acα2-3Galβ1-3GalNAcα-O-TVPAAVVVA) that induces abnormalities in normal cells similar to those in interstitial cystitis/painful bladder syndrome cells in vitro, including decreased proliferation, decreased tight junction formation, and increased paracellular permeability. We screened inactive APF derivatives for their ability to block antiproliferative activity of asialylated-APF ('as-APF') in normal bladder cells and determined the ability of as-APF-blocking derivatives to normalize tight junction protein expression, paracellular permeability, and/or proliferation of interstitial cystitis/painful bladder syndrome cells. Only two of these derivatives [Galβ1-3GalNAcα-O-TV-(d-pipecolic acid)-AAVVVA and Galβ1-3GalNAcα-O-TV-(d-proline)-AAVVVA] blocked as-APF antiproliferative activity in normal cells (p < 0.001 for both). Both of these antagonists also 1) significantly increased mRNA expression of ZO-1, occludin, and claudins 1, 4, 8, and 12 in interstitial cystitis/painful bladder syndrome cells by qRT-PCR; 2) normalized interstitial cystitis/painful bladder syndrome epithelial cell tight junction protein expression and tight junction formation by confocal immunofluorescence microscopy; and 3) decreased paracellular permeability of (14) C-mannitol and (3) H-inulin between confluent interstitial cystitis/painful bladder syndrome epithelial cells on Transwell plates, suggesting that these potent APF antagonists may be useful for the development as interstitial cystitis/painful bladder syndrome therapies.

Decrease of Trefoil factor 2 in cats with feline idiopathic cystitis

OBJECTIVE

To obtain new insights into aetiological backgrounds, and to search for diagnostic biomarkers by assessing the difference in urinary proteins between cats with spontaneous feline idiopathic cystitis (FIC) and healthy controls.

MATERIALS AND METHODS

Urine supernatants of 18 cats with FIC and 18 healthy control cats, and bladder biopsies of two FIC diseased cats and four healthy controls were included in the study. The Bradford method was used to determine protein quantity in urine supernatants. Urine was separated by two-dimensional (2-D) gel electrophoresis. Selected protein spots were excised from two-dimensional gels and analysed with tandem mass spectrometry. Validation of Trefoil factor 2 expression was realized with Western blot and immunohistochemistry. Western blot signal intensities were quantified with image quant software.

RESULTS

Eleven differentially expressed protein spots were identified between the 2-D gels of cats with FIC and control cats. Ten spots (only visible in the FIC gel) were identified as albumin and one spot (only visible in the control gel) was identified as Trefoil factor 2.Using quantification of Western blot signal intensities and immunohistochemistry a decrease in Trefoil factor 2 (TFF2) in cats with FIC could be revealed for the first time.

CONCLUSION

Deficiency in TFF2 possibly leads to impaired repairing abilities and immune response of the urothelium. The result could be a greater susceptibility to injury, inflammation and relapse. Therefore TFF2 deficiency might be an important event in FIC pathogenesis. Detection of a decrease in urinary TFF2 could serve as diagnostic biomarker, facilitating diagnosis. As FIC can serve as an animal model for human painful bladder syndrome/interstitial cystitis, the findings of this study might also be valuable for interstitial cystitis research and should be further investigated.

Quantitative proteomics identifies a beta-catenin network as an element of the signaling response to Frizzled-8 protein-related antiproliferative factor

Antiproliferative factor (APF), a Frizzled-8 protein-related sialoglycopeptide involved in the pathogenesis of interstitial cystitis, potently inhibits proliferation of normal urothelial cells as well as certain cancer cells. To elucidate the molecular mechanisms of the growth-inhibitory effect of APF, we performed stable isotope labeling by amino acids in cell culture analysis of T24 bladder cancer cells treated with and without APF. Among over 2000 proteins identified, 54 were significantly up-regulated and 48 were down-regulated by APF treatment. Bioinformatic analysis revealed that a protein network involved in cell adhesion was substantially altered by APF and that β-catenin was a prominent node in this network. Functional assays demonstrated that APF down-regulated β-catenin, at least in part, via proteasomal and lysosomal degradation. Moreover, silencing of β-catenin mimicked the antiproliferative effect of APF whereas ectopic expression of nondegradable β-catenin rescued growth inhibition in response to APF, confirming that β-catenin is a key mediator of APF signaling. Notably, the key role of β-catenin in APF signaling is not restricted to T24 cells, but was also observed in an hTERT-immortalized human bladder epithelial cell line, TRT-HU1. In addition, the network model suggested that β-catenin is linked to cyclooxygenase-2 (COX-2), implying a potential connection between APF and inflammation. Functional assays verified that APF increased the production of prostaglandin E(2) and that down-modulation of β-catenin elevated COX-2 expression, whereas forced expression of nondegradable β-catenin inhibited APF-induced up-regulation of COX-2. Furthermore, we confirmed that β-catenin was down-regulated whereas COX-2 was up-regulated in epithelial cells explanted from IC bladder biopsies compared with control tissues. In summary, our quantitative proteomics study describes the first provisional APF-regulated protein network, within which β-catenin is a key node, and provides new insight that targeting the β-catenin signaling pathway may be a rational approach toward treating interstitial cystitis.

Neural control of the lower urinary tract: peripheral and spinal mechanisms

This review deals with individual components regulating the neural control of the urinary bladder. This article will focus on factors and processes involved in the two modes of operation of the bladder: storage and elimination. Topics included in this review include: (1) The urothelium and its roles in sensor and transducer functions including interactions with other cell types within the bladder wall ("sensory web"), (2) The location and properties of bladder afferents including factors involved in regulating afferent sensitization, (3) The neural control of the pelvic floor muscle and pharmacology of urethral and anal sphincters (focusing on monoamine pathways), (4) Efferent pathways to the urinary bladder, and (5) Abnormalities in bladder function including mechanisms underlying comorbid disorders associated with bladder pain syndrome and incontinence.

Paediatric painful bladder syndrome/interstitial cystitis: diagnosis and treatment

To describe the pathophysiology, diagnosis and controversies surrounding the diagnosis and pharmacological treatments of painful bladder syndrome/interstitial cystitis (PBS/IC) in children, we reviewed adult and paediatric literature pertaining to PBS/IC. Paediatric PBS/IC presents similarly to adult PBS/IC. The diagnosis is made by exclusion. Paediatric PBS/IC patients complain most commonly of urinary frequency, and abdominal pain occurs in up to 88% of affected children. Enuresis may also be a presenting complaint. Urinalysis and urine cultures are unremarkable. Management of paediatric PBS/IC is similar to that of adult PBS/IC, and non-surgical management includes dietary, lifestyle and pharmacological therapy. Pharmacological options include pentosan polysulfate, amitriptyline, hydroxyzine, cimetidine or intravesical therapies (dimethyl sulfoxide or 'therapeutic solution').