RECRUITMENT, DISTRIBUTION AND PHENOTYPES OF MAST CELLS IN INTERSTITIAL CYSTITIS

Comparative analysis of surgical prognostic between HIC and NHIC patients after cystoscopy with hydrodistention

This study aims to clarify the pathogenic mechanism of interstitial cystitis (IC), which has led to uncertainty in its diagnosis and treatment. We examined data from 18 interstitial cystitis with Hunner lesions (HIC) and 18 interstitial cystitis without Hunner lesions (NHIC) patients, including their clinical information, urodynamic test results, and maximum bladder capacity. A 1-year follow-up tracked disease progression. Postoperative recovery showed that HIC patients experienced significantly greater improvements in Visual Analog Scale pain scores compared to NHIC patients (P = .0049). This trend continued at the 6-month mark (P = .0056). Over the 1-year follow-up, NHIC patients exhibited a statistically significant improvement in Pain and Urgency/Frequency scores, while HIC patients had a gradual overall score increase from preoperative to postoperative stages. However, no significant differences were observed in either group at 1 year postoperatively compared to preoperative scores. This study revealed distinct differences between HIC and NHIC patients, including reduced bladder volumes and more severe nociceptive pain in HIC patients. Early analgesic interventions effectively alleviated discomfort in HIC patients. The combination of cystoscopic hydrodistention and water dilatation was highly effective in relieving pain symptoms in HIC patients but increased the risk of recurrence, necessitating recurrent bladder infusion and timely therapeutic adjustments. In contradiction to prior paradigms, the surgical intervention of cystoscopic water hydrodistention also yielded favorable outcomes among NHIC patients.

Mast cell distribution and prevalence in the murine urinary bladder

BACKGROUND

Mast cells have been implicated in the pathology of various urinary bladder disorders. However, the distribution of mast cells throughout urinary bladder tissue remains uncertain despite mast cell prevalence being relatively well-defined. Using a mouse tissue model, this study aims to characterise the prevalence and distribution of mast cells throughout the urinary bladder.

METHODS

Bladder tissues were collected from six C57BL/6J female mice. Mast cell prevalence was quantified by flow cytometry, based on the expression of the following characteristic markers: CD45, CD117 and FcɛRIα. The toluidine blue stain assessed mast cell distribution, size, and proximity to vasculature. A repeated measures one-way ANOVA was used to evaluate the density of mast cells between the discrete layers of the urinary bladder, and an ordinary one-way ANOVA was used to assess potential differences between mast cell size across the urinary bladder wall.

RESULTS

It was determined that mast cells compose less than 4% of all live leukocytes in the urinary bladder. They were also found to be more prominent in the lamina propria and detrusor muscle layers, compared to the urothelium and adventitia. In addition, 20.89% of mast cells were located near vasculature, which may be an important factor in consideration of their function and potential to contribute to various bladder pathologies, such as cystitis or overactive bladder.

CONCLUSION

These findings provide a baseline understanding of mast cell prevalence and distribution throughout the urinary bladder.

The Model of Interstitial Cystitis for Evaluating New Molecular Strategies of Interstitial Regeneration in Humans

Given the recent evidence in the clinical application of regenerative medicine, mostly on integumentary systems, we focused our interests on recent bladder regeneration approaches based on mesenchymal stem cells (MSCs), platelet-rich plasma (PRP), and hyaluronic acid (HA) in the treatment of interstitial cystitis/bladder pain syndrome (IC/BPS) in humans. IC/BPS is a heterogeneous chronic disease with not-well-understood etiology, characterized by suprapubic pain related to bladder filling and urothelium dysfunction, in which the impairment of immunological processes seems to play an important role. The histopathological features of IC include ulceration of the mucosa, edema, denuded urothelium, and increased detection of mast cells and other inflammatory cells. A deeper understanding of the molecular mechanism underlying this disease is essential for the selection of the right therapeutic approach. In fact, although various therapeutic strategies exist, no efficient therapy for IC/BPS has been discovered yet. This review gives an overview of the clinical and pathological features of IC/BPS, with a particular focus on the molecular pathways involved and a special interest in the ongoing few investigational therapies in IC/BPS, which use new regenerative medicine approaches, and their synergetic combination. Good knowledge of the molecular aspects related to stem cell-, PRP-, and biomaterial-based treatments, as well as the understanding of the molecular mechanism of this pathology, will allow for the selection of the right and best use of regenerative approaches of structures involving connective tissue and epithelia, as well as in other diseases.

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

Introduction

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

Methods

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

Results

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

Discussion

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

Can montelukast sodium be an alternative treatment in the treatment of interstitial cystitis?

Background

The leukotriene D4 receptors have been detected in human bladder detrusor myocytes, and they can play the role of interstitial cystitis etiology.

Aim

Our study aims to explain the role of mast cells histologically and immunohistochemically in the pathogenesis and the effectiveness of montelukast that leukotriene D4 receptor antagonist in the treatment of interstitial cystitis.

Subjects and Methods

Twenty-four Wistar albino adult female rats were used. Group 1 (n = 8): control (sham) group, Group 2 (n = 8): interstitial cystitis group, and Group 3 (n = 8): treatment group. Groups 2 and 3 rats were administered 75 mg/kg cyclophosphamide four times every three days intraperitoneally. The rats in the treatment group were started on montelukast sodium as 10 mg/kg, 1 × 1/day per orally after the last administration of cyclophosphamide and were given for 14 days. Mast cells in the bladder tissues were examined histologically, and the presence of IL-6, 8, VEGF, and TNF alpha was examined immunohistochemically.

Results

Thin transitional epithelium, loose connective tissue, weak smooth muscle bundles, and signs of chronic inflammation were observed in the interstitial cystitis group. Regenerated transitional epithelium, intact basement membrane, compact lamina propia, thick smooth muscle bundles, and rare inflammatory cells were observed after the treatment with the montelukast. Mast cells were decreased in bladder tissue after treatment. IL-6, IL-8, VEGF, and TNF alpha levels were significantly decreased after treatment.

Conclusions

We found that inflammatory mediators were significantly reduced after treatment with montelukast in the interstitial cystitis group. Montelukast can be used as an effective drug in the treatment of interstitial cystitis.

A Bibliometric Analysis of Urologic Chronic Pelvic Pain Syndrome From 2000 to 2022

Purpose

Urologic chronic pelvic pain syndrome has attracted a lot of attention in the new century, and an increasing number of relevant studies have been published. Therefore, we performed a bibliometric analysis of these publications, hoping to show the current research hotspots and future research trends.

Methods

The articles on were selected from the Web of Science Core Collection. Countries, authors, references and keywords in the field were visualized and analyzed using CiteSpace and VOSViewer software.

Results

A total of 1014 articles on urologic chronic pelvic pain syndrome were identified, with "chronic pelvic pain syndrome" being the most common keyword, with a strong association with "interstitial cystitis" and "chronic prostatitis". The hotspot of urologic chronic pelvic pain syndrome research has gradually shifted from chronic prostatitis / urologic chronic pelvic pain syndrome to cystitis/bladder pain syndrome over the past few years. Future research tends to focus on urologic chronic pelvic pain syndrome etiology, including oxidative stress and inflammation.

Conclusion

Research on urologic chronic pelvic pain syndrome is steadily growing. The United States has made the most prominent contribution in this area, and the share of China's contribution is expected to grow further. The etiology of urologic chronic pelvic pain syndrome, including inflammation and oxidative stress, have been the focus of current research and developmental trends in the future research.

Dehydrated Human Amnion-Chorion Membrane Extracts Can Ameliorate Interstitial Cystitis in Rats by Down-Regulating Inflammatory Cytokines and Protein Coding Genes: A Preclinical Study

The study aimed to investigate the therapeutic impact of intravesical instillation of dehydrated human amnion-chorion membrane (HACM) extracts based on the primary pathological feature of interstitial cystitis (IC). We divided 15 female Sprague-Dawley rats into three groups: sham control, IC, and treatment group. IC was induced by 400-µL lipopolysaccharide (1 µg/µL), and it was replaced with normal saline in the sham control group. After IC induction, 300 µL dehydrated HACM extracts (3 mg/kg) were instilled into rats’ urinary bladder weekly for 3 weeks. General histology, inflammatory cytokines, NF-κB, oxidative markers, and western blots results were examined. The urothelial denudation, mast-cell infiltration, and tissues fibrosis were all ameliorated. The elevated TNF-α, IL-1β, IL-6, IL-8, and NF-κB were all down-regulated by dehydrated HACM extracts (p < 0.05). For reactive oxygen species, increased malondialdehyde, decreased superoxide dismutase, and decreased glutathione peroxidase were all reversed (p < 0.05). In apoptosis of IC, elevated Bax and suppressed Bcl-2 were improved (p < 0.05) after instillation. In fibrosis, dysregulated TGFβ/R-Smads/Snail was corrected by the instillation of dehydrated HACM (p < 0.05). In conclusion, dehydrated HACM extracts could be a powerful remedy in treating IC by reconstructing the damaged urothelium, reducing mast-cell infiltration and inflammatory reactions, and ameliorating fibrotic changes.

Molecular Mechanisms and Key Processes in Interstitial, Hemorrhagic and Radiation Cystitis

Simple Summary

Pathologies of the bladder are called cystitis. They cause discomfort for the patient. Due to persistent pain, bleeding, urinary incontinence, and uncontrolled urination, the chronic forms cause considerable degradation to patient quality of life. Currently, there is no curative treatment for the most severe forms. This is both an economic and a societal problem. Although the different forms of cystitis have different causes, they share common mechanisms. We propose to describe in detail the key processes and the associated mechanisms involved in abacterial cystitis.

Abstract

Cystitis is a bladder disease with a high rate of prevalence in the world population. This report focuses on Interstitial Cystitis (IC), Hemorrhagic Cystitis (HC) and Chronic Radiation Cystitis. These pathologies have different etiologies, but they share common symptoms, for instance, pain, bleeding, and a contracted bladder. Overall, treatments are quite similar for abacterial cystitis, and include bladder epithelium protective or anti-inflammatory agents, alleviating pain and reducing bleeding. This review summarizes the mechanisms that the pathologies have in common, for instance, bladder dysfunction and inflammation. Conversely, some mechanisms have been described as present in only one pathology, such as neural regulation. Based on these specificities, we propose identifying a mechanism that could be common to all the above-mentioned pathologies.

Defining Molecular Treatment Targets for Bladder Pain Syndrome/Interstitial Cystitis: Uncovering Adhesion Molecules

Bladder pain syndrome/interstitial cystitis (BPS/IC) is a debilitating pain syndrome of unknown etiology that predominantly affects females. Clinically, BPS/IC presents in a wide spectrum where all patients report severe bladder pain together with one or more urinary tract symptoms. On bladder examination, some have normal-appearing bladders on cystoscopy, whereas others may have severely inflamed bladder walls with easily bleeding areas (glomerulations) and ulcerations (Hunner’s lesion). Thus, the reported prevalence of BPS/IC is also highly variable, between 0.06% and 30%. Nevertheless, it is rightly defined as a rare disease (ORPHA:37202). The aetiopathogenesis of BPS/IC remains largely unknown. Current treatment is mainly symptomatic and palliative, which certainly adds to the suffering of patients. BPS/IC is known to have a genetic component. However, the genes responsible are not defined yet. In addition to traditional genetic approaches, novel research methodologies involving bioinformatics are evaluated to elucidate the genetic basis of BPS/IC. This article aims to review the current evidence on the genetic basis of BPS/IC to determine the most promising targets for possible novel treatments.

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.

β-Defensin 2, an Antimicrobial Peptide, as a Novel Biomarker for Ulcerative Interstitial Cystitis; Can β-Defensin 2 Suspect the Dysbiosis of Urine Microbiota?

As urine is not sterile, inflammatory reactions caused by dysbiosis of the urinary microbiota may induce interstitial cystitis. A study was conducted to determine whether β-defensin 2 (BD-2), a specific antimicrobial peptide in the bladder, could be used as a novel diagnostic marker for ulcerative interstitial cystitis (IC). Urine samples from three female groups were examined: healthy controls (n = 34, Control group), non-Hunner type IC (n = 40, NHIC group), and Hunner type IC (n = 68, HIC group). Urine samples were collected via a transurethral catheter and assayed for BD-2 levels using enzyme linked immunosorbent assay. Under general or regional anesthesia, cystoscopy with diagnostic and therapeutic hydrodistension was performed in NHIC and HIC groups patients. These patients underwent a biopsy of the bladders. Based on the urinary specimens from 142 patients, BD-2 expression was found to be 18-fold higher in patients with Hunner type IC than in patients with non-Hunner type IC. The enhanced secretion of BD-2 exhibited a strong correlation with increased mast cell counts associated with bladder IC pathology. Enhanced urinary secretion of the antimicrobial peptide BD-2 from Hunner type IC patients associated with clinical phenotypes and demonstrated relatively robust levels to be used as a potential biomarker. Moreover, the increased urinary level of BD-2 may suggest a new possibility of biomarkers caused by dysbiosis of the urinary microbiota in ulcerative IC.

P2X7 Receptor Blockade Protects Against Acrolein-Induced Bladder Damage: A Potential New Therapeutic Approach for the Treatment of Bladder Inflammatory Diseases

Inflammatory conditions of the urinary bladder have been shown to be associated with urothelial damage and loss of function. The purinergic P2X7 receptor has been implicated in several inflammatory conditions. The aim of this study was to investigate the role of the P2X7 receptor in acrolein-induced inflammatory damage using the porcine urinary bladder. For this purpose, an ex-vivo model of porcine urothelial damage induced by direct instillation of acrolein into the whole bladder lumen was used. To determine the role of the P2X7 receptor, the bladders were pre-incubated with a selective P2X7 receptor antagonist, A804598 (10 μM), for 1 h. The effects of the acrolein-induced urothelial damage on the bladder’s function were assessed by examining the bladder wall contractile response, structure changes, apoptosis, and oxidative stress in the bladder tissues. The acrolein treatment led to significant damage to the urothelium histology, tight junction expression, and contractile responses. Acrolein also induced apoptosis in the mucosa layer. All these acrolein-induced responses were attenuated by pre-treatment with the P2X7 receptor antagonist A804598. Acrolein also significantly induced DNA oxidation in the submucosal layer; however, the P2X7 receptor antagonism did not show any protective effect towards the acrolein-induced oxidative stress. These findings suggested that the P2X7 receptor is involved in the acrolein-induced damage to the urothelium; therefore, the P2X7 receptor antagonists may be a new therapeutic option for the treatment of bladder inflammation.

Comparative safety review of current pharmacological treatments for interstitial cystitis/ bladder pain syndrome

Introduction: Interstitial cystitis (IC)/bladder pain syndrome (BPS) is a frustrating disease of chronic bladder pain associated with lower urinary tract symptoms. Although there are many proposed treatment algorithms, the uncertainty as to their etiology has a negative impact on the therapeutic outcome. Oftentimes combination therapy of drugs with different mechanisms of action will be utilized to relieve the symptoms. With the various treatment options available to patients and providers, there is an ever-growing need to implement drug efficacy as well as safety to promote best practice in use of the approved drug.Areas covered: This review will focus on guideline-based pharmacotherapies as described by the AUA and EAU, specifically oral, and intravesical therapies with the most up-to-date published literature. Pharmacotherapies targeting bladder, and/or systemic factors in the overall treatment of IC/BPS are discussed with a particular focus on efficacy and drug safety evaluation.Expert opinion: IC/BPS is a syndrome that requires bladder targeting agents to restore the urothelium barrier function and inhibit bladder hypersensitivity as well as various drugs with anti-inflammatory effects, and immune modulation effects. Current pharmacotherapies for IC/BPS have various therapeutic effects and adverse effects depending on the dose and individual response.

Feline Idiopathic Cystitis: Pathogenesis, Histopathology and Comparative Potential

Bladder pain syndrome (BPS) is a debilitating disease in humans, particularly women, with patients experiencing chronic, intractable, lower urinary and pelvic pain. Although rodent models have been used, feline idiopathic cystitis (FIC) is a naturally occurring bladder disease of cats that is frequently considered to be the preferred model for BPS. Histologically, FIC is most similar to the non-Hunner BPS subtype. Histology is unnecessary for the clinical diagnosis of FIC but is of great value in elucidating the pathogenesis of this disease so that prevention and therapeutic interventions can be optimized. Further study of the histological features of FIC and BPS is required to determine the significance of Von Brunn's nests, which are invaginations of hyperplastic urothelium that have been associated with irritative bladder stimuli in animals and have been observed in FIC. We review the possible pathogenesis, histopathological similarities and differences between FIC and BPS, and highlight the potential of FIC as a model of BPS.

Improves symptoms and urinary biomarkers in refractory interstitial cystitis/bladder pain syndrome patients randomized to extracorporeal shock wave therapy versus placebo

Extracorporeal shock wave therapy (ESWT) has been shown to improve symptoms in patients with interstitial cystitis/bladder pain syndrome (IC/BPS); however, there is a lack of objective evidence. We measured change of urinary biomarker levels in 25 patients with IC/BPS received ESWT or placebo once a week for 4 weeks. Urines were collected from participants at baseline, 4 and 12 weeks post treatment. A representative 41 inflammatory growth factors, cytokines, and chemokines in urine were measured using a MILLIPLEX immunoassay kit. Symptom bother was assessed by O’Leary-Sant symptom scores (OSS), and visual analog scale (VAS) for pain. The ESWT group exhibited a significant reduction in the OSS and VAS compared to the placebo group 4 weeks post-treatment (P < 0.05), and the effects were persistent at 12 weeks. The difference in urinary markers change in ESWT versus placebo was P = 0.054 for IL4, P = 0.013 for VEGF, and P = 0.039 for IL9 at 4 weeks. The change of urine biomarker was not significant in other biomarkers or all the measured proteins at 12 weeks. The current data suggest that IL4, IL9, and VEGF mediation may be involved in its pathophysiologic mechanisms and response to LESW treatment.

Current standard of care in treatment of bladder pain syndrome/interstitial cystitis

Bladder pain syndrome/interstitial cystitis (BPS/IC) is a debilitating, systemic pain syndrome with a cardinal symptom of bladder related pain with associated systemic symptoms. It is characterized by an inflammation that partially or completely destroys the mucus membrane and can extend into the muscle layer; however, the etiology and pathogenesis is still enigmatic. It has been suggested that mast cell activation, defects in the glycosaminoglycan layer, non-functional proliferation of bladder epithelial cells, neurogenic inflammation, microvascular abnormalities in the submucosal layer, autoimmunity and infectious causes may cause BPS/IC. Available treatment options include general relaxation techniques, patient education, behavioral treatments, physical therapy, multimodal pain therapy, oral (amitriptyline, cimetidine, hydroxyzine) and intravesical treatments (heparin, lidocaine, hyaluronic acid and chondroitin sulfate), hydrodistension and other more invasive treatments. Available treatments are mostly not based on a high level of evidence. Lack of understanding of disease mechanisms has resulted in lack of targeted therapies on this area and a wealth of empirical approaches with usually inadequate efficacy. The aim of this article is to review the available evidence on the pathophysiological mechanisms of BPS/IC as they relate to available treatment options.

Managing Interstitial Cystitis/Bladder Pain Syndrome in Older Adults

In this review, the current literature regarding pharmacotherapy treatment strategies available for the management of interstitial cystitis/bladder pain syndrome in older adults is addressed. The focus is on those treatments described by the American Urologic Association guidelines, organized according to clinical phenotype. Symptoms at presentation can vary with age, with older adults being more likely to experience nocturia, urinary incontinence, and Hunner's lesions than their younger counterparts. As such, treatment of interstitial cystitis/bladder pain syndrome should follow an individualized multimodal plan based on the patient's unique phenotype(s), starting with the most conservative options and escalating as needed. The side-effect profile and medication interactions should be reviewed, especially when treating older adults, requesting the aid of pharmacists or the primary care physician as needed to safely provide treatment.

New Frontiers or the Treatment of Interstitial Cystitis/Bladder Pain Syndrome - Focused on Stem Cells, Platelet-Rich Plasma, and Low-Energy Shock Wave

Interstitial cystitis/bladder pain syndrome (IC/BPS), which is characterized by bladder pain and irritative voiding symptoms, is a frustrating disease without effective treatment. The cause is still largely not understood, although urothelium ischemia/hypoxia, apoptosis, denudation, and infiltration of inflammatory cells are common histopathological findings. The current uncertainty regarding the etiology and pathology of IC/BPS has a negative impact on its timely and successful treatment; therefore, the development of new treatment modalities is urgently needed. Herein, we present advances in our knowledge on this topic and review the potential application of regenerative medicine for the treatment of IC/BPS. This article provides information on the basic characteristics and clinical evidence of stem cells, platelet-rich plasma (PRP), and low-energy shock waves (LESWs) based on a literature review with a search strategy for articles related to IC/BPS, stem cells, PRP, and LESW published in MEDLINE and PubMed. Stem cells, PRP, and LESW, which modulate inflammatory processes and promote tissue repair, have been proven to improve bladder regeneration, relieve bladder pain, inhibit bladder inflammation, and increase bladder capacity in some preclinical studies. However, clinical studies are still in their infancy. Based on the mechanisms of action of stem cells, PRP, and LESW documented in many preclinical studies, the potential applications of regenerative medicine for the treatment of IC/BPS is an emerging frontier of interest. However, solid evidence from clinical studies remains to be obtained.

Interstitial cystitis/bladder pain syndrome: The evolving landscape, animal models and future perspectives

Interstitial cystitis/bladder pain syndrome is a debilitating condition of unknown etiology characterized by persistent pelvic pain with lower urinary tract symptoms and comprises a wide variety of potentially clinically useful phenotypes with different possible etiologies. Current clinicopathological and genomic evidence suggests that interstitial cystitis/bladder pain syndrome should be categorized by the presence or absence of Hunner lesions, rather than by clinical phenotyping based on symptomatology. The Hunner lesion subtype is a distinct inflammatory disease with proven bladder etiology characterized by epithelial denudation and enhanced immune responses frequently accompanied by clonal expansion of infiltrating B cells, with potential engagement of infection. Meanwhile, the non-Hunner lesion subtype is a non-inflammatory disorder with little evidence of bladder etiology. It is potentially associated with urothelial malfunction and neurophysiological dysfunction, and frequently presents with somatic and/or psychological symptoms, that commonly result in central nervous sensitization. Animal models of autoimmune cystitis and neurogenic sensitization might serve as disease models for the Hunner lesion and non-Hunner lesion subtypes, respectively. Here, we revisit the taxonomy of interstitial cystitis/bladder pain syndrome according to current research, and discuss its potential pathophysiology and representative animal models. Categorization of interstitial cystitis/bladder pain syndrome based on cystoscopy is mandatory to design optimized treatment and research strategies for each subtype. A tailored approach that specifically targets the characteristic inflammation and epithelial denudation for the Hunner lesion subtype, or the urothelial malfunction, sensitized/altered nervous system and psychosocial problems for the non-Hunner lesion subtype, is essential for better clinical management and research progress in this complex condition.

Hunner lesion disease differs in diagnosis, treatment and outcome from bladder pain syndrome: an ESSIC working group report

Objectives: There is confusion about the terms of bladder pain syndrome (BPS) and Interstitial Cystitis (IC). The European Society for the Study of IC (ESSIC) classified these according to objective findings [9]. One phenotype, Hunner lesion disease (HLD or ESSIC 3C) differs markedly from other presentations. Therefore, the question was raised as to whether this is a separate condition or BPS subtype.Methods: An evaluation was made to explore if HLD differs from other BPS presentations regarding symptomatology, physical examination findings, laboratory tests, endoscopy, histopathology, natural history, epidemiology, prognosis and treatment outcomes.Results: Cystoscopy is the method of choice to identify Hunner lesions, histopathology the method to confirm it. You cannot distinguish between main forms of BPS by means of symptoms, physical examination or laboratory tests. Epidemiologic data are incomplete. HLD seems relatively uncommon, although more frequent in older patients than non-HLD. No indication has been presented of BPS and HLD as a continuum of conditions, one developing into the other.Conclusions: A paradigm shift in the understanding of BPS/IC is urgent. A highly topical issue is to separate HLD and BPS: treatment results and prognoses differ substantially. Since historically, IC was tantamount to Hunner lesions and interstitial inflammation in the bladder wall, still, a valid definition, the term IC should preferably be reserved for HLD patients. BPS is a symptom syndrome without specific objective findings and should be used for other patients fulfilling the ESSIC definitions.

Molecular pathogenesis of interstitial cystitis/bladder pain syndrome based on gene expression

Interstitial cystitis/painful bladder syndrome (IC/PBS) is a chronic bladder inflammation that leads to chronic bladder pain and urinary urgency and frequency. The presentation of IC/PBS is heterogeneous, and it is classified as ulcerative IC/PBS and nonulcerative IC/PBS. The main cause of IC/PBS is thought to be a persistent inflammatory condition in the bladder, though the actual pathophysiology has not been identified yet. Although the underlying pathophysiology of IC/PBS is not completely understood, several theories for the etiology of this syndrome have been suggested, including deficiency of the glycosaminoglycan covering urothelium surface that results in leaky urothelium infection, immunological etiology, activated mast cells, neural changes, and inflammation. In addition, there are no gold standards for the detection of this disorder to date. So, determination of gene expression and its role in different signaling pathways in the pathogenesis of this heterogeneous disorder contribute to the more efficient cognition of the pathophysiology of this disease and to the design of effective treatments and molecular diagnostic methods for IC/PBS.

Distribution of mast cell subtypes in interstitial cystitis: implications for novel diagnostic and therapeutic strategies?

AIMS

To identify the presence and geographical distribution of mast cell (MC) subtypes: MC_T (tryptase positive-chymase negative) and MC_TC (tryptase positive-chymase positive) in bladder tissue.

METHODS

Bladder tissue was obtained from patients with painful bladder syndrome/interstitial cystitis (n=14) and normal histology from University Hospital Southampton tissue bank. Sequential tissue slices were immunohistochemically stained for MC subtypes using anti-MC tryptase (for MC_T and MC_TC) and anti-MC chymase (for MC_TC). Stained sections were photographed, and positively stained MCs were quantified using ImageJ. Data were analysed using descriptive statistics and individual paired t-tests.

RESULTS

There was a significant difference in the density of MCs between each layer of the disease bladder, with the greatest accumulation within the detrusor (p<0.001). There was a significant increase in MC_TC subtype in the lamina (p=0.009) in painful bladder syndrome/interstitial cystitis.

CONCLUSIONS

Our results suggest that mastocytosis is present within all layers of disease bladder, especially the muscle layer. The varying increase in MC subtypes in the lamina and mucosa may explain the variability in painful bladder syndrome/interstitial cystitis symptoms. A high influx of MC_TC in the mucosa of individuals who also had ulceration noted within their diagnostic notes may be of the Hunner's ulcer subclassification. These findings suggest a relationship between the pathogenesis of MC subtypes and the clinical presentation of painful bladder syndrome/interstitial cystitis. A cohort study would further elucidate the diagnostic and/or therapeutic potential of MCs in patients with painful bladder syndrome/interstitial cystitis.

Digital quantitative analysis of mast cell infiltration in interstitial cystitis

AIMS

To evaluate the significance of mast cell infiltration in interstitial cystitis (IC) by comparison with equally inflamed controls using a digital quantification technique.

METHODS

Bladder biopsy specimens from 31 patients with Hunner type IC and 38 patients with non-Hunner type IC were analyzed. Bladder biopsy specimens from 37 patients without IC, including 19 non-specific chronic cystitis ("non-IC cystitis") specimens and 18 non-inflamed bladder ("normal bladder") specimens, were used as controls. Mast cell tryptase-, CD3-, CD20-, and CD138-immunoreactive cells were quantified using digital image analysis software to evaluate both mast cell and lymphoplasmacytic cell densities. Mast cell and lymphoplasmacytic cell densities were counted independently in the entire lamina propria and detrusor areas and compared among the four groups.

RESULTS

In the lamina propria, there were no significant differences in mast cell and lymphoplasmacytic cell densities between Hunner type IC and non-IC cystitis or between non-Hunner type IC and normal bladder specimens. In the detrusor, the mast cell densities were not significantly different among the four groups. Mast cell density was correlated with lymphoplasmacytic cell density, but not with clinical parameters.

CONCLUSIONS

Mast cell density is not significantly different between IC specimens and non-IC control specimens with a similar degree of background inflammation. The intensity of mast cell infiltration generally correlated with that of lymphoplasmacytic cells. We conclude that mast cell count is of no value in the differential diagnosis between IC and other etiologies.

A standard for terminology in chronic pelvic pain syndromes: A report from the chronic pelvic pain working group of the international continence society

AIMS

Terms used in the field of chronic pelvic pain (CPP) are poorly defined and often confusing. An International Continence Society (ICS) Standard for Terminology in chronic pelvic pain syndromes (CPPS) has been developed with the aim of improving diagnosis and treatment of patients affected by chronic pelvic pain syndromes. The standard aims to facilitate research, enhance therapy development and support healthcare delivery, for healthcare providers, and patients. This document looks at the whole person and all the domains (organ systems) in a systematic way.

METHODS

A dedicated working group (WG) was instituted by the ICS Standardisation Steering Committee according to published procedures. The WG extracted information from existing relevant guidelines, consensus documents, and scientific publications. Medline and other databases were searched in relation to each chronic pelvic pain domain from 1980 to 2014. Existing ICS Standards for terminology were utilized where appropriate to ensure transparency, accessibility, flexibility, and evolution. Consensus was based on majority agreement.

RESULTS

The multidisciplinary CPPS Standard reports updated consensus terminology in nine domains; lower urinary tract, female genital, male genital, gastrointestinal, musculoskeletal, neurological aspects, psychological aspects, sexual aspects, and comorbidities. Each is described in terms of symptoms, signs and further evaluation.

CONCLUSION

The document presents preferred terms and definitions for symptoms, signs, and evaluation (diagnostic work-up) of female and male patients with chronic pelvic pain syndromes, serving as a platform for ongoing development in this field. Neurourol. Urodynam. 36:984-1008, 2017. © 2016 Wiley Periodicals, Inc.

The place of antifungal treatment in interstitial cystitis

Background and objectives:

Initial study to treat interstitial cystitis with anti-fungal treatment.

Methods and results:

This is an initial report about anti-fungal treatment in three patients with interstitial cystitis. All patients had been diagnosed and receiving treatment for at least two years. Various modalities had led only to minimal improvement. Anti-fungal therapy in the form of fluconazole was commenced in these patients. There was significant response in two cases; the third one had a moderate response.

Conclusion:

Anti-fungal treatment may play a role in the treatment of interstitial cystitis; further elaborate studies are needed. Research is also needed to study the role of fungal infection in the pathogenesis of interstitial cystitis.

Urinary bladder hypersensitivity and dysfunction in female mice following early life and adult stress

Early adverse events have been shown to increase the incidence of interstitial cystitis/painful bladder syndrome in adulthood. Despite high clinical relevance and reports of stress-related symptom exacerbation, animal models investigating the contribution of early life stress to female urological pain are lacking. We examined the impact of neonatal maternal separation (NMS) on bladder sensitivity and visceral neuroimmune status both prior-to, and following, water avoidance stress (WAS) in adult female mice. The visceromotor response to urinary bladder distension was increased at baseline and 8d post-WAS in NMS mice, while colorectal sensitivity was transiently increased 1d post-WAS only in naïve mice. Bladder micturition rate and output, but not fecal output, were also significantly increased following WAS in NMS mice. Changes in gene expression involved in regulating the stress response system were observed at baseline and following WAS in NMS mice, and WAS reduced serum corticosterone levels. Cytokine and growth factor mRNA levels in the bladder, and to a lesser extent in the colon, were significantly impacted by NMS and WAS. Peripheral mRNA levels of stress-responsive receptors were differentially influenced by early life and adult stress in bladder, but not colon, of naïve and NMS mice. Histological evidence of mast cell degranulation was increased in NMS bladder, while protein levels of protease activated receptor 2 (PAR2) and transient receptor potential ankyrin 1 (TRPA1) were increased by WAS. Together, this study provides new insight into mechanisms contributing to stress associated symptom onset or exacerbation in patients exposed to early life stress.

[CLINICAL EFFICACY OF DIETARY MANIPULATION AS COMPLEMENTARY AND ALTERNATIVE MEDICINE THERAPIES ON FEMALE INTERSTITIAL CYSTITIS PATIENTS]

(Objectives) We examined the clinical efficacy of dietary manipulation (DM) for female patients with interstitial cystitis (IC) in stable condition who were followed in our hospital. (Patients and methods) This study included 20 female patients with IC in rather stable condition who were followed at our hospital. In cooperation with the nutrition control team, we created a basic IC diet menu for 1 month (total daily calories, 1,500 kcal; protein, 65 g; fat, 40 g; carbohydrate, 220 g; water, 1,000 ml; salt, 7 g). Data regarding daily food intake and food-related symptoms were collected by detailed interview of each patient conducted by the doctors, nurses, and nutritionists at our hospital. In accordance with the abovementioned nutrition control, we set meal menu to control IC symptoms and advised the patients to reduce the intake of specific food items to the maximum possible extent.The following food items were removed from or restricted in the diet of patients: tomatoes, tomato products, soy, tofu product (seasoning was acceptable), spices (pepper, curry powder, mustard, horseradish, etc.), excessive potassium, citrus, high-acidity-inducing substances (caffeine, carbonate, and citric acid), etc. We evaluated the following factors to determine the efficacy of this diet menu 3 months after the start of the intervention: O'Leary-Sant symptom index (OSSI), O'Leary-Sant problem index (OSPI), urgency visual analogue scale (UVAS) score, (0, no urgency; 10, severe urgency), bladder or pelvic pain VAS (PVAS) score, (0, no pain; 10, worst possible pain), and numerical patient-reported quality of life (QOL) index (0, highly satisfied; 6, highly dissatisfied). (Results) OSSI and OSPI improved from 11.7 to 10.1 (p<0.0001), and from 10.7 to 8.8 (p=0.01), respectively. The UVAS score significantly reduced from 6.4 to 4.8, and the PVAS score significantly improved from 6.5 to 4.8 (p<0.0001). The patient-reported QOL index significantly improved from 5.1 to 3.9 (p<0.0001). (Conclusion) Although repeated notes were taken and patients who were followed up for a long term were consulted on the meal, as appropriate, at the time of visit, DM was found to alleviate the symptoms of IC. DM as a systematic treatment modality for IC should be attempted more aggressively because of its non-invasiveness, without alterations to the other IC treatments.

Mast Cell-Mediated Mechanisms of Nociception

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

Inflammation characteristics in bladder pain syndrome ESSIC type 3C/classic interstitial cystitis

OBJECTIVES

Interstitial cystitis is regarded as a heterogenous syndrome with two distinguishable forms: the non-ulcer and the classic form of interstitial cystitis, the latter with Hunner's lesions; or bladder pain syndrome type 3C and non-Hunner bladder pain syndrome, respectively.

METHODS

A cohort of 379 patients diagnosed with interstitial cystitis was studied. Nitric oxide release from the bladder was measured using a chemiluminescence nitric oxide analyzer. Bladder biopsies from the patients and healthy controls were analyzed by routine histopathological examination. Biopsies from a subset of patients and controls were also analyzed by immunohistochemistry and cytokine gene expression by real-time polymerase chain reaction.

RESULTS

Patients with bladder pain syndrome type 3C/classic interstitial cystitis had considerably higher levels of nitric oxide as compared with non-Hunner bladder pain syndrome/non-ulcer interstitial cystitis patients and healthy individuals, and showed histologically a chronic inflammation in the bladder mucosa, with abundant mast cell infiltration in all layers of the bladder wall. No inflammation was noted in non-Hunner bladder pain syndrome/non-ulcer interstitial cystitis patients. The isoenzymes inducible nitric oxide synthase, the catalyst in the nitric oxide production, was strongly expressed in the inflammatory cells in the bladder mucosa of bladder pain syndrome type 3C/classic interstitial cystitis patients. In addition, the expression of the pro-inflammatory cytokines interleukin-6 and interleukin-17A messenger ribonucleic acid, and of anti-inflammatory interleukin-10 messenger ribonucleic acid showed significantly increased levels in bladder pain syndrome type 3C/classic interstitial cystitis compared with healthy controls.

CONCLUSION

Bladder pain syndrome type 3C/classic interstitial cystitis is a distinct inflammatory disease and in many aspects shares features of inflammatory autoimmune diseases. These findings could open up novel research avenues with expectations for new targets for pharmacological treatment.

Are mast cells still good biomarkers for bladder pain syndrome/interstitial cystitis?

PURPOSE

ESSIC identifies mast cell infiltrates of detrusor muscle as a diagnostic criterion for bladder pain syndrome/interstitial cystitis. However, an increased mast cell count is also characteristic of overactive bladder syndrome. The lack of uniformity in mast cell detection methods hampers data comparison. Using state-of-the-art techniques we investigated whether mast cells differ among bladder conditions.

MATERIALS AND METHODS

We analyzed bladder biopsies from 56 patients, including 31 with bladder pain syndrome/interstitial cystitis with (12) or without (19) Hunner lesions, 13 with overactive bladder syndrome and 12 without bladder symptoms to determine the quantity, location, distribution and activation of mast cells using immunohistochemistry with anti-mast cell tryptase. Patients were allocated to study groups by key bladder symptoms commonly used to define conditions (pain and major urgency).

RESULTS

Subepithelial mast cell localization (p <0.001) and an increased detrusor mast cell count (p = 0.029) were characteristic of bladder pain syndrome/interstitial cystitis with Hunner lesions. The optimal cutoff of 32 detrusor mast cells per mm(2) achieved only 68% accuracy with 38% positive predictive value. No difference was observed between bladder pain syndrome/interstitial cystitis without Hunner lesions and overactive bladder syndrome. Patient groups differed in lymphocyte infiltration (p = 0.001), nodular lymphocyte aggregates (p <0.001) and urothelium integrity (p <0.001).

CONCLUSIONS

Subepithelial mast cell distribution was characteristic of bladder pain syndrome/interstitial cystitis with Hunner lesions. Detrusor mastocytosis had poor predictive value for bladder pain syndrome/interstitial cystitis. Mast cell assessment did not distinguish bladder pain syndrome/interstitial cystitis without Hunner lesions from overactive bladder syndrome.

Chronic pelvic allodynia is mediated by CCL2 through mast cells in an experimental autoimmune cystitis model

The cause of chronic pelvic pain in interstitial cystitis/painful bladder syndrome (IC/PBS) remains unclear; autoimmunity is a possible etiology. We have recently shown that injection of a single immunogenic peptide of uroplakin 3A (UPK3A 65-84) induces experimental autoimmune cystitis (EAC) in female BALB/cJ mice that is unique among experimental models in accurately reflecting both the urinary symptoms and pelvic pain of IC/PBS. The aim of this project was to identify the roles of mast cells and mast cell chemoattractant/activator monocyte chemoattractant protein-1 [chemokine (C-C motif) ligand 2 (CCL2)] in the allodynia in this model. We immunized 6- to 8-wk-old female BALB/cJ mice with UPK3A 65-84 peptide and, 5-40 days later, observed increased responses to stimulation of the suprapubic abdominal and hindpaw surfaces with von Frey monofilaments compared with mice injected with adjuvant alone. Suprapubic and hindpaw tactile allodynia responses by EAC mice were blocked by instillation of lidocaine into the bladder but not by lidocaine in the uterus, confirming the bladder as the source of the hypersensitivity. Markedly increased numbers of activated mast cells and expression of CCL2 were found in the bladder after immunization with UPK3A 65-84. Hypersensitive responses were inhibited by mast cell stabilizer cromolyn sodium and antagonists of histamine receptors 1 and 2. Furthermore, BALB/cJ mice with deletion of the Ccl2 or chemokine (C-C motif) receptor 2 gene exhibited markedly reduced allodynia and accumulation of mast cells after UPK3A 65-84 immunization. These results show that UPK3A 65-84 immunization causes chronic visceral allodynia and suggest that it is mediated by CCL2-driven mast cell accumulation in the bladder.

Mast cells in chronic inflammation, pelvic pain and depression in women

Inflammatory and neuroinflammatory processes are increasingly recognized as critical pathophysiologic steps in the development of multiple chronic diseases and in the etiology of persistent pain and depression. Mast cells are immune cells now viewed as cellular sensors in inflammation and immunity. When stimulated, mast cells release an array of mediators to orchestrate an inflammatory response. These mediators can directly initiate tissue responses on resident cells, and may also regulate the activity of other immune cells, including central microglia. New evidence supports the involvement of peripheral and central mast cells in the development of pain processes as well as in the transition from acute, to chronic and neuropathic pain. That behavioral and endocrine states can increase the number and activation of peripheral and brain mast cells suggests that mast cells represent the immune cells that peripherally and centrally coordinate inflammatory processes in neuropsychiatric diseases such as depression and anxiety which are associated with chronic pelvic pain. Given that increasing evidence supports the activated mast cell as a director of common inflammatory pathways/mechanisms contributing to chronic and neuropathic pelvic pain and comorbid neuropsychiatric diseases, mast cells may be considered a viable target for the multifactorial management of both pain and depression.

Inhibition of nitric oxide synthase prevents muscarinic and purinergic functional changes and development of cyclophosphamide-induced cystitis in the rat

Nitric oxide (NO) has pivotal roles in cyclophosphamide- (CYP-) induced cystitis during which mucosal nitric oxide synthase (NOS) and muscarinic M5 receptor expressions are upregulated. In cystitis, urothelial muscarinic NO-linked effects hamper contractility. Therefore we wondered if a blockade of this axis also affects the induction of cystitis in the rat. Rats were pretreated with saline, the muscarinic receptor antagonist 4-DAMP (1 mg/kg ip), or the NOS inhibitor L-NAME (30 mg/kg ip) for five days. 60 h before the experiments the rats were treated with saline or CYP. Methacholine-, ATP-, and adenosine-evoked responses were smaller in preparations from CYP-treated rats than from saline-treated ones. Pretreatment with 4-DAMP did not change this relation, while pretreatment with L-NAME normalized the responses in the CYP-treated animals. The functional results were strengthened by the morphological observations; 4-DAMP pretreatment did not affect the parameters studied, namely, expression of muscarinic M5 receptors, P1A1 purinoceptors, mast cell distribution, or bladder wall enlargement. However, pretreatment with L-NAME attenuated the differences. Thus, the current study provides new insights into the complex mechanisms behind CYP-induced cystitis. The NO effects coupled to urothelial muscarinic receptors have a minor role in the development of cystitis. Inhibition of NOS may prevent the progression of cystitis.

Cytokine expression in patients with bladder pain syndrome/interstitial cystitis ESSIC type 3C

PURPOSE

Bladder wall nitric oxide production in patients with bladder pain syndrome type 3C is increased compared to undetectable nitric oxide in patients with nonHunner bladder pain syndrome and healthy controls. However, the underlying mechanism/s of the increased nitric oxide production is largely unknown. We compared mRNA expression of a select group of cytokines in patients with bladder pain syndrome/interstitial cystitis type 3C and in pain-free controls.

MATERIALS AND METHODS

Cold cup biopsies from 7 patients with bladder pain syndrome type 3C and 6 healthy subjects were analyzed. mRNA expression of IL-4, 6, 10 and 17A, iNOS, TNF-α, TGF-β and IFN-γ was estimated by real-time polymerase chain reaction. IL-17 protein expression was determined by immunohistochemistry. Mast cells were labeled with tryptase to evaluate cell appearance and count.

RESULTS

IL-6, 10 and 17A, and iNOS mRNA levels as well as the number of mast cells infiltrating the bladder mucosa were significantly increased in patients with bladder pain syndrome type 3C compared to healthy controls. TNF-α, TGF-β and IFN-γ mRNA levels were similar in patients and controls. IL-17A expression at the protein level was up-regulated and localized to inflammatory cells and urothelium in patients with bladder pain syndrome type 3C.

CONCLUSIONS

Patients with bladder pain syndrome/interstitial cystitis had increased mRNA levels of IL-17A, 10 and 6, and iNOS. IL-17A might be important in the inflammatory process. To our knowledge the increase in IL-17A is a novel finding that may have new treatment implications.

The mouse cyclophosphamide model of bladder pain syndrome: tissue characterization, immune profiling, and relationship to metabotropic glutamate receptors

Abstract Painful bladder syndrome/Interstitial cystitis (PBS/IC) is a chronic disorder characterized clinically by recurring episodes of pelvic pain and increased urination frequency, significantly impairing patients' quality of life. Despite this, there is an unmet medical need in terms of effective diagnostics and treatment. Animal models are crucial in this endeavor. Systemic chronic administration of cyclophosphamide (CYP) in mice has been proposed as a relevant preclinical model of chronic bladder pain. However, molecular mechanisms underlying the pathogenesis of this model are lacking. Here, we show that mice, subjected to repetitive systemic injections of CYP, developed mild inflammatory response in bladder tissue characterized by submucosal edema, moderate increase in proinflammatory cytokine gene expression, and mastocytosis. No signs of massive inflammatory infiltrate, tissue hemorrhages, mucosal ulcerations and urothelium loss were observed. Instead, CYP treatment induced urothelium hyperplasia, accompanied by activation of proliferative signaling cascades, and a decrease in the expression of urothelium-specific markers. Metabotropic glutamate (mGlu) receptors have been implicated in chronic pain disorders. CYP administration induced differential changes in mGlu receptors mRNA levels in bladder tissue, without affecting gene expression at spinal cord level, pointing to the potential link between peripheral mGlu receptors and inflammation-induced bladder malfunction and hyperalgesia. Taken together, these data indicate that chronic CYP treatment in mice is a model of PBS mostly relevant to the major, nonulcerative subtype of the syndrome, characterized by a relatively unaltered mucosa and a sparse inflammatory response. This model can help to elucidate the pathogenetic mechanisms of the disease.

Expression and function of transforming growth factor-β isoforms and cognate receptors in the rat urinary bladder following cyclophosphamide-induced cystitis

Numerous proinflammatory cytokines have been implicated in the reorganization of lower urinary tract function following cyclophosphamide (CYP)-induced cystitis. The present study investigated the functional profile of three pleiotropic transforming growth factor-β (TGF-β) isoforms and receptor (TβR) variants in the normal and inflamed (CYP-induced cystitis) rat urinary bladder. Our findings indicate that TGF-β (1, 2, and 3) and TβR (1, 2, and 3) transcript and protein expression were regulated to varying degrees in the urothelium or detrusor smooth muscle following intermediate (48 h; 150 mg/kg ip) or chronic (75 mg/kg ip; once every 3 days for 10 days), but not acute (4 h; 150 mg/kg ip), CYP-induced cystitis. Conscious, open-outlet cystometry was performed to determine whether aberrant TGF-β signaling contributes to urinary bladder dysfunction following intermediate (48 h) CYP-induced cystitis. TβR-1 inhibition with SB505124 (5 μM) significantly (p ≤ 0.001) decreased voiding frequency and increased bladder capacity (2.5-fold), void volume (2.6-fold), and intercontraction intervals (2.5-fold) in CYP-treated (48 h) rats. Taken together, these results provide evidence for 1) the involvement of TGF-β in lower urinary tract neuroplasticity following urinary bladder inflammation, 2) a functional role of TGF-β signaling in the afferent limb of the micturition reflex, and 3) urinary bladder TβR-1 as a viable target to reduce voiding frequency with cystitis.

Physiological relevance of LL-37 induced bladder inflammation and mast cells

PURPOSE

We established the physiological relevance of LL-37 induced bladder inflammation. We hypothesized that 1) human urinary LL-37 is increased in pediatric patients with spina bifida, 2) LL-37 induced inflammation occurs in our mouse model via urothelial binding and is dose dependent and 3) LL-37 induced inflammation involves mast cells.

MATERIALS AND METHODS

To test our first hypothesis, we obtained urine samples from 56 pediatric patients with spina bifida and 22 normal patients. LL-37 was measured by enzyme-linked immunosorbent assay. Our second hypothesis was tested in C57Bl/6 mice challenged with 7 LL-37 concentrations intravesically for 1 hour. At 24 hours tissues were examined histologically and myeloperoxidase assay was done to quantitate inflammation. In separate experiments fluorescent LL-37 was instilled and tissues were obtained immediately (time = 0) and at 24 hours (time = 24). To test our final hypothesis, we performed immunohistochemistry for mast cell tryptase and evaluated 5 high power fields per bladder to determine the mean number of mast cells per mm(2).

RESULTS

Urinary LL-37 was 89-fold higher in patients with spina bifida. Mouse LL-37 dose escalation experiments revealed increased inflammation at higher LL-37 concentrations. Fluorescent LL-37 demonstrated global urothelial binding at time = 0 but was not visible at time = 24. Immunohistochemistry for tryptase revealed mast cell infiltration in all tissue layers. At higher concentrations the LL-37 challenge led to significantly greater mast cell infiltration.

CONCLUSIONS

Urinary LL-37 was significantly increased in pediatric patients with spina bifida. To our knowledge we report for the first time that LL-37 can elicit profound, dose dependent bladder inflammation involving the urothelium. Finally, inflammation propagation involves mast cells.

Methods and incentives for the early diagnosis of bladder pain syndrome/interstitial cystitis

INTRODUCTION

The concept of interstitial cystitis (IC) has changed dramatically during the last decades, eventually representing a symptom complex with varying contents. To include all patients with bladder pain, the umbrella term 'bladder pain syndrome' (BPS) has been suggested, incorporating the classic presentation of IC as a separate phenotype. This change of concepts has not been uncontroversial. Bladder pain syndrome often has a profound effect on the patients' quality of life. Generally, recognition of this problem complex is hampered by insufficient familiarity in the medical community. The correct diagnosis is often delayed by several years and may be preceded by multiple medical consultations and treatment attempts. There is no doubt that an early and correct diagnosis is of great significance for the patient.

AREAS COVERED

In this article, a critical review of methods and means to approach the diagnosis is presented including some notes of current controversies.

EXPERT OPINION

The key to an early diagnosis is symptom recognition. We are dealing with a heterogeneous concept including various phenotypes. The successful treatment requires understanding and expedient use of objective means, such as cystoscopy, biopsy and input from the multidisciplinary team. In the literature, limited evidence exists for the management of BPS/IC, due to heterogeneity in methodology and description of the syndrome(s). A more consequent use of available methods is desirable. For the immediate future, better understanding of the aetiology, pathogenesis and presentation of various BPS/IC phenotypes is indispensable.

Clinical characteristics differ considerably between phenotypes of bladder pain syndrome/interstitial cystitis

OBJECTIVE

Bladder pain syndrome/interstitial cystitis (BPS/IC) is one of the most bothersome conditions in urological practice. This syndrome includes a heterogeneous collection of underlying pathological conditions. Compared to the classic IC with a Hunner lesion, now denominated European Society for the Study of Interstitial Cystitis (ESSIC) type 3C, the non-Hunner type of BPS/IC appears different concerning demographic, endoscopic and histological findings, as well as the response to all forms of treatment. The objective of this study was to determine whether there are additional dissimilarities in clinical presentation between the main phenotypes of BPS/IC.

MATERIAL AND METHODS

In total, 393 BPS/IC patients (210 type 3C and 183 non-Hunner), diagnosed according to National Institute of Diabetes and Digestive and Kidney Diseases and ESSIC criteria, were studied by surveying the clinical records including micturition diaries.

RESULTS

In this clinical material, BPS/IC ESSIC type 3C accounted for 55% of cases. Patients with non-Hunner disease were on average 20 years younger at the time of diagnosis. Furthermore, there was a marked and significant difference in bladder capacity under general anaesthesia (p < 0.0001).

CONCLUSIONS

The findings in the present series, together with previously published reports by this group and by others, confirm the striking differences between the main forms of BPS/IC and underline the indispensability of adequate subtyping in clinical studies.