Intravesical chondroitin sulfate inhibits recruitment of inflammatory cells in an acute acid damage "leaky bladder" model of cystitis

The urothelial barrier in interstitial cystitis/bladder pain syndrome: its form and function, an overview of preclinical models

PURPOSE OF REVIEW

Investigating bladder pain syndrome/interstitial cystitis (IC/BPS) preclinically is challenging. Various research models have been used to mimic the urothelial barrier closely and replicate the disease. The aim of this review is to discuss preclinical research related to the urothelial barrier in context of IC/BPS.

RECENT FINDINGS

In vivo models mimic IC/BPS mainly with toxic substances in the urine, with protaminesulfate and proteoglycan deglycolysation resembling a temporary impaired barrier as seen in IC/BPS. This temporary increased permeability has also been found in vitro models. Glycosaminoglycan replenishment therapy has been described, in vivo and in vitro, to protect and enhance recover properties of the urothelium. The roles of immune and neurogenic factors in the pathogenesis of IC/BPS remains relatively understudied.

SUMMARY

Preclinical studies provide opportunities to identify the involvement of specific pathologic pathways in IC/BPS. For further research is warranted to elucidate the primary or secondary role of permeability, together with inflammatory and neurogenic causes of the disease.

The Molecular Mechanism and Therapeutic Application of Autophagy for Urological Disease

Autophagy is a lysosomal degradation process known as autophagic flux, involving the engulfment of damaged proteins and organelles by double-membrane autophagosomes. It comprises microautophagy, chaperone-mediated autophagy (CMA), and macroautophagy. Macroautophagy consists of three stages: induction, autophagosome formation, and autolysosome formation. Atg8-family proteins are valuable for tracking autophagic structures and have been widely utilized for monitoring autophagy. The conversion of LC3 to its lipidated form, LC3-II, served as an indicator of autophagy. Autophagy is implicated in human pathophysiology, such as neurodegeneration, cancer, and immune disorders. Moreover, autophagy impacts urological diseases, such as interstitial cystitis /bladder pain syndrome (IC/BPS), ketamine-induced ulcerative cystitis (KIC), chemotherapy-induced cystitis (CIC), radiation cystitis (RC), erectile dysfunction (ED), bladder outlet obstruction (BOO), prostate cancer, bladder cancer, renal cancer, testicular cancer, and penile cancer. Autophagy plays a dual role in the management of urologic diseases, and the identification of potential biomarkers associated with autophagy is a crucial step towards a deeper understanding of its role in these diseases. Methods for monitoring autophagy include TEM, Western blot, immunofluorescence, flow cytometry, and genetic tools. Autophagosome and autolysosome structures are discerned via TEM. Western blot, immunofluorescence, northern blot, and RT-PCR assess protein/mRNA levels. Luciferase assay tracks flux; GFP-LC3 transgenic mice aid study. Knockdown methods (miRNA and RNAi) offer insights. This article extensively examines autophagy's molecular mechanism, pharmacological regulation, and therapeutic application involvement in urological diseases.

Decreased autophagic activity of detrusor cells is involved in the inflammatory response of interstitial cystitis/bladder pain syndrome

INTRODUCTION AND HYPOTHESIS

Genome-wide association studies suggest that autophagy plays an important regulatory role in inflammatory and autoimmune diseases. Inflammation and immune regulation disorders are involved in the occurrence and development of interstitial cystitis/bladder pain syndrome (IC/BPS). However, the changes and roles of autophagy in IC/BPS have not been reported. Therefore, this study aimed to investigate bladder autophagy and inflammation changes in patients with IC/BPS.

METHODS

Bladder specimens (n = 5) from patients with cystectomy due to end-stage IC/BPS were collected. The bladder samples of the control group (n = 5) were derived from the normal area bladder tissue after radical cystectomy. H&E and toluidine blue staining were used for histological evaluation. The co-location of LC3, alpha-smooth muscle actin (α-SMA), and autophagosome was investigated with double-labeled immunofluorescence and transmission electron microscopy (TEM). The expression of IL-6, TNF-α, Bax, caspase-3, and BCL-2 in the detrusor layer was analyzed using immunohistochemistry (IHC) and Western blot (WB).

RESULTS

Compared with the control group, bladder tissue from IC/BPS patients revealed thinner and edematous epithelium with many mast cells (P < 0.05) infiltrating into the muscle layer. By using TEM (P < 0.05), double-labeled immunofluorescence (P < 0.05), and Western blot (P < 0.05) in IC/BPS patients, autophagy was also found and was significantly increased in detrusor myocytes. IHC and WB indicate the expression of BCL-2 (P < 0.05) was decreased, while IL-6, TNF-α, Bax, and caspase-3 expression was elevated (P < 0.05).

CONCLUSIONS

The number of autophagosomes in detrusor cells was increased in IC/BPS. However, autophagy of detrusor muscle cells may not have sufficient phagocytic activity to effectively remove damaged proteins and mitochondria, which may lead to the continued deterioration of IC/BPS inflammation and apoptosis.

Surface Shave: Revealing the Apical-Restricted Uroglycome

This study aimed to investigate the highly differentiated urothelial apical surface glycome. The functions of the mammalian urothelium, lining the majority of the urinary tract and providing a barrier against toxins in urine, are dependent on the correct differentiation of urothelial cells, relying on protein expression, modification, and complex assembly to regulate the formation of multiple differentiated cell layers. Protein glycosylation, a poorly studied aspect of urothelial differentiation, contributes to the apical glycome and is implicated in the development of urothelial diseases. To enable surface glycome characterization, we developed a method to collect tissue apical surface N- and O-glycans. A simple, novel device using basic laboratory supplies was developed for enzymatic shaving of the luminal bladder urothelial surface, with subsequent release and mass spectrometric analysis of apical surface O- and N-glycans, the first normal mammalian urothelial N-glycome to be defined. Trypsinization of superficial glycoproteins was tracked using immunolabeling of the apically expressed uroplakin 3a protein to optimize enzymatic release, without compromising the integrity of the superficial urothelial layer. The approach developed for releasing apical tissue surface glycans allowed for comparison with the N-glycome of the total porcine bladder urothelial cells and thus identification of apical surface glycans as candidates implicated in the urothelial barrier function. Data are available in MassIve: MSV000087851.

MRI as a Tool to Assess Interstitial Cystitis Associated Bladder and Brain Pathologies

Interstitial cystitis/bladder pain syndrome (IC/BPS) is a chronic, often incapacitating condition characterized by pain seeming to originate in the bladder in conjunction with lower urinary tract symptoms of frequency and urgency, and consists of a wide range of clinical phenotypes with diverse etiologies. There are currently no diagnostic tests for IC/BPS. Magnetic resonance imaging (MRI) is a relatively new tool to assess IC/BPS. There are several methodologies that can be applied to assess either bladder wall or brain-associated alterations in tissue morphology and/or pain. IC/BPS is commonly associated with bladder wall hyperpermeability (BWH), particularly in severe cases. Our group developed a contrast-enhanced magnetic resonance imaging (CE-MRI) approach to assess BWH in preclinical models for IC/BPS, as well as for a pilot study for IC/BPS patients. We have also used the CE-MRI approach to assess possible therapies to alleviate the BWH in preclinical models for IC/BPS, which will hopefully pave the way for future clinical trials. In addition, we have used molecular-targeted MRI (mt-MRI) to quantitatively assess BWH biomarkers. Biomarkers, such as claudin-2, may be important to assess and determine the severity of BWH, as well as to assess therapeutic efficacy. Others have also used other MRI approaches to assess the bladder wall structural alterations with diffusion-weighted imaging (DWI), by measuring changes in the apparent diffusion coefficient (ADC), diffusion tensor imaging (DTI), as well as using functional MRI (fMRI) to assess pain and morphological MRI or DWI to assess anatomical or structural changes in the brains of patients with IC/BPS. It would be beneficial if MRI-based diagnostic tests could be routinely used for these patients and possibly used to assess potential therapeutics.

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

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

Comparison of Intravesical Hyaluronic Acid, Chondroitin Sulfate, and Combination of Hyaluronic Acid-Chondroitin Sulfate Therapies in Animal Model of Interstitial Cystitis

Purpose

Three intravesical treatment agents were compared in an interstitial cystitis rat model: chondroitin sulfate, hyaluronic acid, and combined hyaluronic acid-chondroitin sulfate.

Methods

Thirty-five female rats were divided into 5 groups: control (group I), isotonic (group II), chondroitin sulfate (group III), hyaluronic acid (group IV), and hyaluronic acid-chondroitin sulfate (group V). Chemical cystitis was induced in all experimental groups by intravesical instillation of 1 mL of hydrogen peroxide (H₂O₂) for 15 minutes via the transurethral route. The treatment was administered every other day for 3 sessions 2 days after inducing chemical cystitis. Groups II, III, IV, and V received 1 mL of 0.9% NaCl, 1 mL of 0.2% sodium chondroitin sulfate, 1 mL of low-molecular-weight hyaluronic acid, and 1 mL of 2% sodium chondroitin sulfate+1.6% sodium hyaluronic acid, respectively. On day 7, the animals were sacrificed and the bladders were removed for histopathological and immunohistochemical assessments.

Results

Significant between-group differences were found in vascular congestion (P=0.006). The grade of submucosal edema in groups II and IV was significantly higher than in group I (P=0.006, P=0.006, respectively). In group I, the grade of granulation tissue was lower than the other 4 groups, but no significant difference was found between the remaining groups (P=0.016). Neutrophil cell infiltration was more intense in groups II and IV than in group I (P=0.006, P=0.006, respectively). Significant differences in the leukocyte and mast cell count were detected between groups II and IV (P<0.001, P<0.001, respectively). Abnormal zonula occludens-1 and uroplakin-III immunoreactivity in group II was higher than in groups I, III, or V (P=0.002, P=0.010, respectively). Interleukin-8 expression was lower in group V than in group II (P=0.001).

Conclusion

A single treatment of chondroitin sulfate and combined hyaluronic acid-chondroitin sulfate treatment demonstrated efficacy by suppressing inflammation and achieving improvements in the urothelium.

The role of glycosaminoglycans in the management of chronic pelvic pain: a systematic review

INTRODUCTION

Glycosaminoglycans (GAGs) are involved in the pathogenesis of several urologic chronic diseases. Thus, GAGs replenishment therapy is widely reported as a therapeutic tool for chronic pelvic pain (CPP) conditions such as interstitial cystitis/bladder pain syndrome (IC/BPS) and prostate pain syndrome/chronic prostatitis. In this article we reviewed the current status of evidence on the clinic applications of glycosaminoglycans (GAGs) in the CPP.

EVIDENCE ACQUISITION

A literature search from inception was performed according to the Preferred Reporting Items for Systematic Reviews and Meta-analysis statement to identify clinical trials, randomized controlled trials, meta-analyses, and guidelines.

EVIDENCE SYNTHESIS

A total of 29 papers were identified regarding the use of GAGs in CPP.

CONCLUSIONS

GAGs replenishment therapy results are encouraging in chronic forms of pelvic pain even though well-powered randomized clinical trials are needed to better comprehend the exact role of this treatment.

Improving the barrier function of damaged cultured urothelium using chondroitin sulfate

AIMS

To determine whether glycosaminoglycan (GAG) replenishment is able to improve recovery of a deficient urothelial barrier, chondroitin sulfate (CS) instillations were tested using an in vitro model. Porcine urothelial cells (Ucells) were terminally differentiated in culture conditions to construct a urothelial layer with a functional barrier. This layer was damaged to compromise barrier function to simulate a key characteristic of bladder pain syndrome/interstitial cystitis. The functional effect of subsequent treatment with CS was evaluated.

METHODS

Primary porcine Ucells were isolated and cultured on inserts. Differentiation of cells was evaluated with immunohistochemical analysis for the presence of umbrella cells, tight junctions and CS. Transepithelial electrical resistance (TEER) measurements were performed to evaluate barrier function. Protamine was used to simulate mild urothelial damage. CS 0.2% (vol/vol), a GAG, was subsequently instilled in the treatment group. The recovery of barrier function was further evaluated with TEER measurements. The Student t test was used for the analysis of results.

RESULTS

After induction of differentiation, the Ucells expressed barrier markers and a functional barrier was established (measured by high TEER). TEER decreased significantly after instillation with protamine. CS instillation improved recovery of TEER significantly measured after 7 hours (84% vs 22% in controls). After 24 hours; however, the TEER was comparable in both experimental groups.

CONCLUSION

CS instillation improves the recovery of the urothelial barrier after damage in vitro. This functional experiment shows that CS improves recovery of damaged urothelial function, which supports the hypothesis behind the mechanism of action of GAG-replenishment therapy.

GAG replenishment therapy for bladder pain syndrome/interstitial cystitis

AIMS

To present a rationale for the inclusion of urothelial coating dysfunction in the etipathogenesis of bladder pain syndrome/interstitial cystitis (BPS/IC) and the preclinical and clinical evidence in support of glycosaminoglycan (GAG) replenishment therapy in the treatment of BPS/IC, supplemented by the clinical experience of medical experts in the field and patient advocates attending a symposium on GAG replenishment at ESSIC'17, the annual Meeting of the International Society for the Study of Bladder Pain Syndrome, held in Budapest, Hungary in 2017.

RESULTS

The urothelial GAG layer has a primary role in providing a permeability barrier to prevent penetration of urinary toxins and pathogens into the bladder wall. Disruption of the GAG layer contributes to the development of BPS/IC. The evidence shows that replenishment of GAGs can restore the GAG layer in BPS/IC, reducing inflammation, pain, and other symptoms.

CONCLUSIONS

Although data from large randomized controlled studies are limited, long clinical observation and the experience of clinicians and patients support the beneficial effects of intravesical GAG replenishment therapy for providing symptomatic relief for patients with BPS/IC.

Preclinical Animal Studies of Intravesical Recombinant Human Proteoglycan 4 as a Novel Potential Therapy for Diseases Resulting From Increased Bladder Permeability

OBJECTIVE

To test in an animal model the hypothesis that recombinant human proteoglycan 4 (rhPRG4; lubricin), a highly O-glycosylated mucin-like glycoprotein, may be a novel surface-active therapeutic for treating bladder permeability with comorbid bowel permeability. Previously we showed that inducing bladder permeability in rats with dilute protamine sulfate (PS) produced colonic permeability and visceral hypersensitivity, suggesting increased bladder permeability could represent an etiologic factor in both interstitial cystitis-bladder pain syndrome and irritable bowel syndrome.

METHODS

We used an animal model of catheterized ovariectomized female rats instilled intravesically with 1 mg/mL PS for 10 minutes that after 24 hours were treated with 1.2 mg/mL lubricin or with vehicle alone. After 24 hours the bladder and colon were removed and permeability assessed electrophysiologically with the Ussing chamber to measure the transepithelial electrical resistance. A second set of rats was treated identically, except permeability was assessed on day 3 and on day 5 using contrast-enhanced magnetic resonance imaging with gadolinium diethylenetriamine penta-acetic acid instilled into the bladder.

RESULTS

Intravesical lubricin reversed bladder permeability induced by PS and prevented the concomitant increase in permeability induced in the bowel (organ crosstalk). The protective effect was confirmed with magnetic resonance imaging, and because individual rats could be followed over time, the impermeability of the bladder restored by rhPRG4 remained for 5 days.

CONCLUSION

These data indicate that instillation of rhPRG4 into a permeable bladder can restore its normally impermeable state, and that the effect lasts for 5 days and also prevents bowel symptoms often comorbid with interstitial cystitis-bladder pain syndrome.

Intravesical Glycosaminoglycan Replacement with Chondroitin Sulphate (Gepan(®) instill) in Patients with Chronic Radiotherapy- or Chemotherapy-Associated Cystitis

Background and Objective

Intravesical instillation of glycosaminoglycans is a promising option for the treatment of chronic cystitis, as it supports the regeneration of the damaged urothelial layer. We investigated the efficacy of short-term intravesical chondroitin sulphate treatment (six courses of instillation) in patients with chronic radiotherapy- or chemotherapy-associated cystitis.

Methods

This prospective, observational study included patients with chronic radiotherapy- or chemotherapy-associated cystitis, who received six once-weekly intravesical instillations of 0.2 % chondroitin sulphate 40 mL. Every week, patients recorded their symptoms and their benefits and tolerance of treatment, using a self-completed questionnaire.

Results

The study included 16 patients (mean age 68.5 years; 50 % male). During the study, a reduction in all evaluated parameters was observed. After one dose of chondroitin sulphate, symptom improvement was observed in 38 % of patients, and after the second dose, an additional 31 % of patients showed improvement. At week 6, 80 % of patients had either improved or were symptom free, and significant improvements in urinary urgency (p = 0.0082), pollakisuria (p = 0.0022), urge frequency (p = 0.0033) and lower abdominal pain (p = 0.0449) were observed. Haematuria, present in 9 of the 16 patients at baseline, was completely resolved in all cases after 6 weeks. The majority of patients (93 %) evaluated the tolerance of chondroitin sulphate as ‘good’ or ‘very good’. No treatment-related adverse events were reported.

Conclusion

Intravesical administration of chondroitin sulphate was effective for the treatment of radiotherapy- or chemotherapy-associated cystitis. Even short-term treatment appears to be effective in reducing symptoms and improving the quality of life of patients.

Glycosaminoglycans: how much do we know about their role in the bladder?

The urothelium is a unique lining in the body providing a protective barrier against the penetration of toxic agents, urine, and bacteria. The glycosaminoglycan (GAG) layer consists of a thick mucus layer of glycoproteins and proteoglycans on the surface of the urothelial cells. Damage to the GAG layer disrupts its protective barrier function giving rise to increased permeability into the deep layers of the urothelium and bladder, causing inflammation and pain. Replenishment of the GAG layer appears to restore normal permeability allowing for urothelial layer recovery.

Clinical guidelines for interstitial cystitis and hypersensitive bladder updated in 2015

Clinical guidelines for interstitial cystitis and hypersensitive bladder have been updated as of 2015. The guidelines define interstitial cystitis by the presence of hypersensitive bladder symptoms (discomfort, pressure or pain in the bladder usually associated with urinary frequency and nocturia) and bladder pathology, after excluding other diseases explaining symptoms. Interstitial cystitis is further classified by bladder pathology; either Hunner type interstitial cystitis with Hunner lesions or non-Hunner type interstitial cystitis with mucosal bleeding after distension in the absence of Hunner lesions. Hypersensitive bladder refers to a condition, where hypersensitive bladder symptoms are present, but bladder pathology or other explainable diseases are unproven. Interstitial cystitis and hypersensitive bladder severely affect patients' quality of life as a result of disabling symptoms and/or comorbidities. Reported prevalence suggestive of these disorders varies greatly from 0.01% to >6%. Pathophysiology would be an interaction of multiple factors including urothelial dysfunction, inflammation, neural hyperactivity, exogenous substances and extrabladder disorders. Definite diagnosis of interstitial cystitis and hypersensitive bladder requires cystoscopy with or without hydrodistension. Most of the therapeutic options lack a high level of evidence, leaving a few as recommended therapeutic options.

Revisiting the Role of Potassium Sensitivity Testing and Cystoscopic Hydrodistention for the Diagnosis of Interstitial Cystitis

OBJECTIVES

To revisit the diagnostic roles of cystoscopic hydrodistention and the potassium sensitivity test (PST) for the diagnosis of interstitial cystitis (IC).

METHODS

We prospectively enrolled 214 patients clinically diagnosed with IC, 125 non-IC patients who underwent video urodynamic studies and PST, and another 144 non-IC patients who underwent cystoscopic hydrodistention before transurethral surgery. The sensitivity, specificity, and positive and negative predictive values were calculated for the PST and glomerulations after cystoscopic hydrodistention.

RESULTS

After cystoscopic hydrodistention, glomerulations developed in 211/214 (98.6%) IC patients and 61/144 (42.4%) of the non-IC patients including patients with stones (45/67, 67%), hematuria (2/5, 40%), and stress urinary incontinence (SUI) (6/17, 35%). When positive glomerulation was defined as grade 2 or more, the sensitivity was 61.7%. The PST was positive in 183/214 (85.5%) IC patients and 7/17 (41%) with hypersensitive bladder, 7/32 (22%) with detrusor overactivity, 5/27 (18%) with SUI, 2/21 (10%) with lower urinary tract symptoms, and 2/25 (8%) with bladder outlet obstruction. The PST had a sensitivity of 85.5% and a specificity of 81.6% for diagnosis of IC. IC patients with a positive PST had a significantly smaller urgency sensation capacity, smaller voided volume, and greater bladder pain score.

CONCLUSIONS

Both the PST and glomerulations after hydrodistention are sensitive indicators of IC, but the specificity of glomerulations in the diagnosis of IC is lower than that of the PST. A positive PST is associated with a more hypersensitive bladder and bladder pain, but not the grade of glomerulations in IC patients. Neither test provided 100% diagnostic accuracy for IC, we might select patients into different subgroups based on different PST and hydrodistention results, not for making a diagnosis of IC but for guidance of different treatments.

Review of intravesical therapies for bladder pain syndrome/interstitial cystitis

Bladder pain syndrome/interstitial cystitis (BPS/IC) is a chronic pain condition characterised by urinary frequency, urgency and pain or discomfort which the patient attributes to the bladder. It is a complex condition to manage and treat and requires a multi-disciplinary and multi-modal approach. As well as lifestyle and behavioural modifications, physical therapy and oral medications, intravesical treatments can be used in the treatment algorithm for BPS/IC. A number of intravesical agents are reviewed in this paper along with the available evidence for their use.

Sulfated glycans in inflammation

Sulfated glycans such as glycosaminoglycans on proteoglycans are key players in both molecular and cellular events of inflammation. They participate in leukocyte rolling along the endothelial surface of inflamed sites; chemokine regulation and its consequential functions in leukocyte guidance, migration and activation; leukocyte transendothelial migration; and structural assembly of the subendothelial basement membrane responsible to control tissue entry of cells. Due to these and other functions, exogenous sulfated glycans of various structures and origins can be used to interventionally down-regulate inflammation processes. In this review article, discussion is given primarily on the anti-inflammatory functions of mammalian heparins, heparan sulfate, chondroitin sulfate, dermatan sulfate and related compounds as well as the holothurian fucosylated chondroitin sulfate and the brown algal fucoidans. Understanding the underlying mechanisms of action of these sulfated glycans in inflammation, helps research programs involved in developing new carbohydrate-based drugs aimed to combat acute and chronic inflammatory disorders.

Contrast enhanced magnetic resonance imaging as a diagnostic tool to assess bladder permeability and associated colon cross talk: preclinical studies in a rat model

PURPOSE

Interstitial cystitis/painful bladder syndrome is a devastating disease associated with multiple symptoms. It is usually diagnosed based on pain, urgency and frequency in the absence of other known causes. To our knowledge there is no diagnostic test to date.

MATERIALS AND METHODS

In a model of rats intravesically exposed to protamine sulfate we performed in vivo diagnostic contrast enhanced magnetic resonance imaging with intravesical administration of Gd-diethylenetriamine pentaacetic acid contrast medium via a catheter to visualize increased bladder urothelium permeability. Gd-diethylenetriamine pentaacetic acid was administered intravenously to visualize secondary tissue effects in the colon.

RESULTS

Bladder urothelium and colon mucosa were assessed 24 hours after bladder protamine sulfate exposure. Enhanced contrast magnetic resonance imaging established bladder urothelium leakage of Gd-diethylenetriamine pentaacetic acid according to the change in magnetic resonance imaging signal intensity in rats exposed to protamine sulfate vs controls (mean ± SD 399.7% ± 68.7% vs 39.2% ± 12.2%, p < 0.0001) as well as colon related uptake of contrast agent (mean 65.2% ± 17.1% vs 20.8% ± 9.8%, p < 0.01) after bladder protamine sulfate exposure. The kinetics of Gd-diethylenetriamine pentaacetic acid uptake and excretion were also assessed during 20 minutes of bladder and 30 minutes of colon exposure with increased signal intensity at 7 and 12 minutes, respectively.

CONCLUSIONS

These preliminary studies indicate that contrast enhanced magnetic resonance imaging can be used to monitor primary bladder urothelium loss of permeability and secondary enhanced contrast medium in the colon mucosa. It can be considered a potential clinical diagnostic method for interstitial cystitis/painful bladder syndrome that involves loss of the permeability barrier. It can also be used to assess visceral organ cross talk.

Clinical comparision of intravesical hyaluronic acid and hyaluronic acid-chondroitin sulphate therapy for patients with bladder pain syndrome/interstitital cystitis

INTRODUCTION

Patients with a history of bladder pain syndrome/interstitial cystitis (BPS/IC) and who responded poorly or unsatisfactorily with previous treatment were compared taking intravesical hyaluronic acid (HA) or hyaluronic acid-chondroitin sulphate (HA-CS).

METHODS

Patients were treated with intravesical instillation with 50 mL sterile sodium hyalurinic acid (Hyacyst, Syner-Med, Surrey, UK) (n = 32) and sodium hyaluronate 1.6% sodium chondroitin sulphate 2% (Ialuril, Aspire Pharma, UK) (n = 33). Intravesical instillations were performed weekly in first month, every 15 days in the second month and monthly in third and fourth months, for a total of 8 doses. Patients were evaluated using a visual analog pain scale (VAS), interstitial cystitis symptom index (ICSI), interstitial cystitis problem index (ICPI), voiding diary for frequency/nocturia, cystometric bladder capacity and voided volume at the beginning and at 6 months. All patients had a potassium sensitivity test (PST) initially. Wilcoxon and Mann-Whitney U tests were used for statistical analysis.

RESULTS

In total, 53 patients met the study criteria. There were 30 patients in the HA-CS group (mean age: 48.47) and 23 patients in the HA group (mean age: 49.61) (p > 0.05). The initial PST was positive in 71.7% patients (38/53) overall with no difference between groups (p > 0.05). Responses for VAS, ICCS, ICPS, 24-hour frequency/nocturia statistically improved in both groups at 6 months. There was no significant difference in symptomatic improvement (p > 0.05). Eight patients had mild adverse events.

CONCLUSION

HA and HA/CS instillation can be effective in BPS/IC patients who do not respond to conservative treatment. An important limitation of our study is that the HA dosage of the 2 treatment arms were different. It would be more appropriate with same HA dosage in both groups; however, there was no commercially available glycosaminoglycan (GAG) substance with same HA dosage for single and combination therapy. Large, long-term randomized studies are required to determine if there is a difference between these treatments.

Standardized cranberry capsules for radiation cystitis in prostate cancer patients in New Zealand: a randomized double blinded, placebo controlled pilot study

PURPOSE

Acute radiation cystitis, inflammation of the bladder, is a common side effect in men receiving external beam radiation for prostate cancer. Although several treatments provide symptomatic relief, there is no effective treatment to prevent or treat radiation cystitis. Cranberry products have been associated with urinary tract health. This study aimed to determine the effect of highly standardized cranberry capsules (containing 72 mg proanthocyanidins [PACS]) compared with that of placebo capsules on the incidence and severity of radiation cystitis.

METHODS

Forty-one men with prostate cancer participated in a double blinded randomized placebo controlled study. Men took one capsule a day at breakfast during treatment and for 2 weeks after treatment completion. Severity of urinary symptoms and the bother these caused were measured using the individual items of the urinary domain of the Modified Expanded Prostate Index Composite (EPIC).

RESULTS

The incidence of cystitis was lower in men taking cranberry capsules (65%) compared with those that took placebo capsules (90%) (p = 0.058); severe cystitis was seen in 30% of men in the cranberry arm and 45% in the placebo arm (p = 0.30). Overall, the incidence of pain/burning was significantly lower in the cranberry cohort (p = 0.045). Men on the low hydration regimen who took cranberry had less pain/burning (p = 0.038), stronger urine steam (p = 0.030) and used significantly fewer pads/liners (p = 0.042), which was significantly different from those on the high hydration regimen (p = 0.028).

CONCLUSION

Men receiving radiation therapy for prostate cancer may benefit from using cranberry capsules, particularly those on low hydration regimens or with baseline urinary symptoms.

Prevention of anti-microbial peptide LL-37-induced apoptosis and ATP release in the urinary bladder by a modified glycosaminoglycan

Interstitial cystitis (IC), often referred to in combination with painful bladder syndrome, is a chronic inflammatory disease of the bladder. Current therapies primarily focus on replenishing urothelial glycosaminoglycan (GAG) layer using GAG analogs and managing pain with supportive therapies. However, the elusive etiology of IC and the lack of animal models to study the disease have been major hurdles developing more effective therapeutics. Previously, we showed an increased urinary concentration of antimicrobial peptide LL-37 in spina bifida patients and used LL-37 to develop a mouse model of cystitis that mimics important clinical findings of IC. Here we investigate (1) the molecular mechanism of LL-37 induced cystitis in cultured human urothelial cells and in mice, (2) the protective effects of GM-0111, a modified GAG, within the context of this mechanism, (3) the physiological and molecular markers that correlate with the severity of the inflammation, and (4) the protective effects of several GAGs using these biomarkers in our LL-37 induced cystitis model. We find that LL-37 quickly induces release of ATP and apoptosis in the urothelium. These changes can be inhibited by a chemically-modified GAG, GM-0111. Furthermore, we also find that GAG analogs provide varying degrees of protection against LL-37 challenge in mice. These findings suggest that GM-0111 and possibly GAG molecules prevent the development of cystitis by blocking the apoptosis and the concurrent release of ATP from the urothelium.

Overactive bladder syndrome and the potential role of prostaglandins and phosphodiesterases: an introduction

In this paper, a general introduction is given, presenting the overactive bladder syndrome (OAB) and its impact on the quality of life and economical burden in patients affected. Moreover, the anatomy, physiology and histology of the lower urinary tract are discussed, followed by a brief overview on the possible role of prostaglandin (PG) and phosphodiesterase type 5 (PDE5) in the urinary bladder. The current literature on the role and distribution of PGE2 and its receptors in the urinary bladder is discussed. In both animal models and in human studies, high levels of signaling molecules such as PG and cGMP have been implicated, in decreased functional bladder capacity and micturition volume, as well as in increased voiding contraction amplitude. As a consequence, inhibition of prostanoid production, the use of prostanoid receptor antagonists, or PDE inhibitors might be a rational way to treat patients with detrusor overactivity. Similarly, prostanoid receptor agonists, or agents that stimulate their production, might have a function in treating bladder underactivity.

Further evidence of endogenous hydrogen sulphide as a mediator of relaxation in human and rat bladder

We investigated the expression of hydrogen sulphide (H2S) in human and rat lower urinary tract (including bladder, prostate and urethra) tissues, and we sought to determine whether H2S induces relaxation of human and Sprague-Dawley (SD) rat bladder strips. Human normal lower urinary tract tissue was obtained for the evaluation of endogenous H2S productivity using a sulphide-sensitive electrode and for the analysis of the expression levels of all three synthases of endogenous H2S, cystathionine β-synthase (CBS), cystathionine γ lyase (CSE) and 3-mercaptopyruvate sulphur transferase (MPST, as known as 3-MST) by Western blot assay. CBS, CSE and MPST were located in human sample slides by immunohistochemistry. Human and male adult SD rat bladder strips were tested for H2S function with a transducer and recorded. All experiments were repeated six times. The endogenous H2S productivity and the H2S synthases had various distributions in the human and rat lower urinary tract tissues and were located in both epithelial and stromal sections. L-cysteine (L-Cys, a substrate of CBS, CSE and MPST) elicited relaxation in a dose-dependent manner on human bladder strips pre-contracted by acetylcholine chloride. This effect could be diminished by the ATP-sensitive potassium ion (KATP) channel blocker glibenclamide (GLB), the CSE inhibitor DL-propargylglycine (PPG) and the CBS inhibitor hydroxylamine (HA). H2S and its three synthases were present in the human and rat lower urinary tract tissues and relaxed human and rat bladder strips, which implied that endogenous H2S might play a role in physiological function and pathological disorders of the lower urinary tract symptoms (LUTS) or overactive bladder (OAB).