The effects of intravesical therapy with hyaluronic acid for painful bladder syndrome: Preliminary Chinese experience and systematic review

Glycosaminoglycan Replacement Therapy with Intravesical Instillations of Combined Hyaluronic Acid and Chondroitin Sulfate in Patients with Recurrent Cystitis, Post-radiation Cystitis and Bladder Pain Syndrome: A Narrative Review

Defects in the glycosaminoglycan layer (GAG) of the bladder mucosa have been identified as a significant contributor to the pathogenesis and clinical progression of chronic inflammatory diseases of the bladder, such as post-radiation cystitis, bladder pain syndrome and recurrent urinary tract infections. This narrative review aims to explore the contemporary evidence on the role of GAG reconstitution with intravesical installations of hyaluronic acid and chondroitin sulfate in the management of those patients, with a goal to provide valuable insights for clinical practice. The reviewed studies consistently demonstrate that GAG reconstitution can result in varying degrees of clinical improvement in patients with post-radiation cystitis, bladder pain syndrome and recurrent urinary tract infections, and is associated with a very favorable safety profile. While the available evidence is growing, its level is still limited, mainly by relatively low number of randomized controlled trials, with small sample sizes. Further research with larger, well-designed trials is needed to solidify the findings and optimize the clinical application of GAG reconstitution.

The effect of intravesical hyaluronic acid therapy on urodynamic and clinical outcomes among women with interstitial cystitis/bladder pain syndrome

OBJECTIVE

Treatment of interstitial cystitis/bladder pain syndrome (IC/BPS) is often delayed because of a lack of objective data during diagnosis. This study was conducted to determine the clinical validity of using urodynamic studies to investigate the effect of intravesical hyaluronic acid (HA) treatment among women with IC/BPS.

MATERIALS AND METHODS

Thirty patients with IC/BPS undergoing 6-month intravesical instillation of HA were recruited. Pretreatment evaluation involved a urinalysis and urinary culture, urinary cytology, a 3-day voiding diary, and cystoscopy with hydrodistention of the bladder. Urodynamic study was performed before and after HA treatment. Symptomatic changes were assessed using a questionnaire covering lower urinary tract symptoms, the O'Leary-Sant symptom index and problem indexes (ICSI and ICPI), and the visual analog scale for pain and urgency. Patient demographics, urinary symptoms, ICSI/ICPI scores, pain and urgency scores, and urodynamic results before and after HA treatment were compared.

RESULTS

Urinary frequency, nocturia, urgency, pelvic pain, bladder capacity, ICSI, and ICPI were significantly improved after HA treatment. Comparing urodynamic parameters, the volumes at first desire to void (FDV) and maximum cystometric capacity were significantly increased after HA treatment. Before HA treatment, a negative correlation existed between the ICSI and ICPI and urodynamic parameters, including maximum flow rate and bladder capacity, but there were no significant correlations after treatment. Before HA treatment, a negative correlation was discovered between nocturia and FDV. However, after HA treatment, there were no significant correlations between urinary symptoms and urodynamic parameters.

CONCLUSIONS

Our results indicate that the improvement of urinary symptoms of IC/BPS after HA treatment is associated with increased FDV and maximum cystometric capacity. The value of FDV and the frequency of nocturia after treatment may become useful objective indicators for prognosis of IC/BPS.

Potassium sensitivity test predicts hydrodistention efficacy in patients with bladder pain syndrome/interstitial cystitis

OBJECTIVE

To determine the possible role of potassium sensitivity test (PST) in predicting the success of hydrodistention (HD) in patients with bladder pain syndrome/interstitial cystitis (BPS/IC).

MATERIAL AND METHODS

Patients who underwent PST before diagnostic cystoscopy and HD were evaluated to collect data regarding the visual analog score (VAS) to assess pain, the voiding diary for frequency of urination/nocturia, mean urine volume per void, interstitial cystitis symptom index, and problem index before HD. Patients were requested to provide the VAS of pain at 1 month and 6 months post-HD. A reduction 2 or more on the VAS of pain was considered as a response adequate to be noted.

RESULTS

The median age of the patients was 46 years. The PST was positive for 27 patients (27/39; 69.2%). At 1 month post-HD, out of the 27 patients with positive PST, 23 (85.2%) were found to have been responsive to HD and 4 (14.8%) were non-responsive. Of the 12 (12/39; 30.8%) patients who showed a negative PST, 7 (58.3%) were non-responsive and 5 (41.7%) were responsive to HD. A logistic regression analysis revealed that PST (p=0.009) was the only parameter that was able to predict HD efficacy at 1 month post-HD.

CONCLUSION

PST was found to be a predictive factor for the short-term efficacy of HD. BPS/IC patients with positive PST are likely to be more susceptible to the damage of mucosal afferent nerve endings, which results in them benefiting from HD to a greater degree.

Role of NLRP3 inflammasome in the development of bladder pain syndrome interstitial cystitis

Although it has been proposed that NOD-like receptor protein 3 (NLRP3) inflammasome activation may have an important contribution to the onset of bladder pain syndrome/interstitial cystitis (BPS/IC), as of today there is still insufficient evidence to accept or to reject this hypothesis. However, taking into consideration that inflammasomes have been already shown as important mediators of cyclophosphamide-induced bladder inflammation and that some studies have also revealed human bladder epithelium expresses high levels of NLRP3, such a hypothesis seems to be reasonable. The purpose of this review is to discuss a scenario that NLRP3 inflammasome is a crucial player in the development of this disease. Identification of a novel mediator of bladder inflammation and pain could lead to emerging new therapeutic strategy and the first causative therapy.

Downregulation of tight junction protein zonula occludens-2 and urothelium damage in a cyclophosphamide-induced mouse model of cystitis

OBJECTIVES

The cyclophosphamide (CYP)-induced model of cystitis in mice closely fits the symptoms of chronic bladder inflammation. Cystitis was recently found to be due to an altered gap junction protein in a rat model. Thus, this study was conducted to evaluate changes in protein expression and composition in the bladder of CYP-treated mice.

MATERIALS AND METHODS

Administration of CYP induced cystitis-related symptoms in mice. Cystometry was assessed and cell junction-associated protein zonula occludens-2 (ZO-2) expression was measured. Voiding interval values (time between voids) were assessed in mice under anesthesia. The bladders were removed for proteomic analysis using label-free quantitative proteomics and liquid chromatography-mass spectrometry. Additionally, immunochemistry (IHC) and Western blot were used to confirm the location and level, respectively, of ZO-2 expression.

RESULTS

Compared to the control group, the voiding interval values and urothelial thickness in the bladder in the CYP-treated group were significantly decreased. Additionally, we identified 105 differentially expressed proteins in the bladder of CYP-treated mice with proteomic analysis. These proteins were involved in cell-cell tight junctions, exocytosis, muscle development, contraction, and regulation, immune responses, proteolysis, and cell adhesion. IHC and Western blot confirmed the downregulation of the tight junction protein ZO-2 in the urothelium of bladder.

CONCLUSIONS

Our results suggest that downregulation in tight junction protein ZO-2 and urothelium damage may have a role in cystitis-related OAB. These changes could be related to the molecular mechanism of cystitis-related OAB.

Gold nanoparticles approach to detect chondroitin sulphate and hyaluronic acid urothelial coating

This study investigated the location of hyaluronic acid (HA)- and chondroitin sulphate (CS)-coated gold nanoparticles in rabbit bladder and evaluated gene expression of CD44, RHAMM and ICAM-1 receptors involved in HA and CS transport into the cell. Gold nanoparticles were synthesised by reduction of gold salts with HA or CS to form HA-AuNPs and CS-AuNPs. Bladder samples were incubated with CS-AuNPs and HA-AuNPs or without glycosaminoglycans. Transmission electron microscopy, optic microscopy and scanning electron microscopy were used to determine the location of the synthesised AuNPs. Real-time PCR was used to analyse expression of urothelial cell receptors CD44, RHAMM, ICAM-1, after ex vivo administration of CS-AuNPs and HA-AuNPs. We showed that HA-AuNPs and CS-AuNPs were located in the cytoplasm and tight junctions of urothelial umbrella cells; this appearance was absent in untreated bladders. There were no significant differences in gene expression levels for CD44, RHAMM and ICAM-1 receptors in treated versus control bladder tissues. In conclusion, we clearly showed the presence of exogenous GAGs in the bladder surface and the tight junctions between umbrella cells, which is important in the regeneration pathway of the urothelium. The GAGs-AuNPs offer a promising approach to understanding the biophysical properties and imaging of urothelial tissue.

Clinical comparison of intravesical hyaluronic acid and chondroitin sulfate therapies in the treatment of bladder pain syndrome/interstitial cystitis

INTRODUCTION

Intravesical glucosaminoglycan (GAG) replacement therapies are commonly used in the treatment of bladder pain syndrome (BPS)/interstitial cystitis (IC). Different intravesical glucosaminoglycan products are currently available. In this prospective study, clinical efficacy of chondroitin sulfate and hyaluronic acid are compared in patients with BPS/IC.

METHODS

Patients were randomized to CS and HA groups. All patients were evaluated for visual analogue pain scale (VAS), interstitial cystitis symptom index (ICSI), interstitial cystitis problem index (ICPI), voiding diary for frequency/nocturia, and mean urine volume per void at the beginning of the therapy and after 6 months. All patients had a potassium sensitivity test (PST) initially. Wilcoxon and Mann-Whitney U tests were used for statistical analysis.

RESULTS

There were 21 patients in both groups. Mean age of patients in CS and HA groups were 47.10 and 48.90, respectively(P > 0.05). Before treatment, Parson's test was positive in 64.3% of patients (27/42) with no difference between groups. VAS of pain, ICSI, ICPI, frequency at 24 h and nocturia results have improved significantly at both treatment arms. Intravesical CS was also found superior to intravesical HA in terms of 24 h frequency, nocturia and ICPI (P < 0.05). No severe adverse effects were reported.

CONCLUSIONS

Data comparing clinical efficiencies of different GAG therapies are very limited. In this study, intravesical CS was found superior to intravesical HA in terms of 24 h frequency, nocturia and ICPI in patients with BPS/IC in short term follow-up. To provide a definitive conclusion on superiority of one GAG therapy to others, further evaluation with long term follow up is required.

Managing chronic bladder diseases with the administration of exogenous glycosaminoglycans: an update on the evidence

Although the pathophysiology of acute chronic cystitis and other 'sensory' disorders, i.e. painful bladder syndrome (PBS) or interstitial cystitis (IC), often remains multifactorial, there is a wide consensus that such clinical conditions may arise from a primary defective urothelium lining or from damaged glycosaminoglycans (GAGs). A 'cascade' of events starting from GAG injury, which fails to heal, may lead to chronic bladder epithelial damage and neurogenic inflammation. To restore the GAG layer is becoming the main aim of new therapies for the treatment of chronic cystitis and PBS/IC. Preliminary experiences with GAG replenishment for different pathological conditions involving the lower urinary tract have been reported. There is a range of commercially available intravesical formulations of these components, alone or in combination. Literature evidence shows that exogenous intravesical hyaluronic acid markedly reduces recurrences of urinary tract infections (UTIs). Patients treated with exogenous GAGs have fewer UTI recurrences, a longer time to recurrence and a greater improvement in quality of life. Exogenous intravesical GAGs have been used for the treatment of PBS/IC. Despite the limitations of most of the studies, findings confirmed the role of combination therapy with hyaluronic acid and chondroitin sulfate as a safe and effective option for the treatment of PBS/IC. To prevent and/or treat radiotherapy and chemotherapy induced cystitis, GAG replenishment therapy has been used showing preliminary encouraging results. The safety profile of exogenous GAGs has been reported to be very favourable, without adverse events of particular significance.