Differences in Mast Cell Infiltration, E-cadherin, and Zonula Occludens-1 Expression Between Patients With Overactive Bladder and Interstitial Cystitis/Bladder Pain Syndrome

The exposure to volatile organic compounds associate positively with overactive bladder risk in U.S. adults: a cross-sectional study of 2007-2020 NHANES

Objective

The aim of this study was to comprehensively investigate the potential relationship between blood volatile organic compounds (VOCs) and overactive bladder (OAB) risk.

Methods

A total of 11,183 participants from the 2007-2020 National Health and Nutrition Examination Survey (NHANES) were included in this cross-sectional study. We used multivariate logistic regression models to investigate the relationship between nine blood VOCs and OAB risk. Restricted cubic spline (RCS) analysis was used to investigate the dose-response relationship between blood VOCs and OAB. In addition, the overall association of blood VOCs with OAB risk was assessed by weighted quantile sum (WQS) regression model. Finally, we conducted subgroup analyses to explore the findings in different high-risk populations.

Results

After adjusting for potential confounders, logistic regression analysis revealed that blood 2,5-dimethylfuran (aOR = 2.940, 95% CI: 1.096-7.890, P = 0.032), benzene (aOR = 1.460, 95% CI: 1.044-2.043, P = 0.027) and furan (aOR = 9.426, 95% CI: 1.421-62.500, P = 0.020) were positively independent associated with the risk of OAB. And dose-response risk curves indicated that 2,5-dimethylfuran, benzene and furan in the blood were linearly positive associated with OAB risk. WQS regression analysis showed that exposure to mixed blood VOCs increased the risk of OAB (OR = 1.29, 95% CI: 1.11-1.49), with furans having the greatest weight. In subgroup analyses, we found that OAB was more susceptible to blood VOCs in young and middle-aged, male, non-hypertensive, and alcohol-drinking populations.

Conclusions

The results of this study indicate that high exposure to VOCs is independently and positively associated with OAB risk in U.S. adults, particularly 2,5-dimethylfuran, benzene, and furan. In addition, age, gender, hypertension and alcohol consumption may influence the association. Our study provided novel epidemiologic evidence to explore the potential role of environmental pollutants in OAB.

Intravesical Instillation of Hyaluronic Acid With Epidermal Growth Factor for Restoring Urothelial Denudation and Alleviating Oxidative Stress in Lipopolysaccharide-Induced Interstitial Cystitis of Rats

PURPOSE

To investigate the efficacy of an intravesical instillation of hyaluronic acid (HA) combined with epidermal growth factor (EGF) for the treatment of interstitial cystitis (IC) using a lipopolysaccharide (LPS)-induced IC animal model.

METHODS

A total of 24 female Sprague-Dawley rats were randomized to 4 groups: sham control, IC, HA, and treatment (HA/ EGF) groups. A polyethylene-50 tube was placed inside the bladder of each animal. IC was induced by twice-weekly instillations of LPS for 3 weeks, which resulted in chronic injury of the urothelium. Animals in the sham control group only received saline instillation. Treatment solutions of HA and HA/EGF were given on days 0, 7, and 14 after IC induction (400 μL of HA in a concentration of 0.4 mg/0.5 mL and 400 μL of NewEpi, a commercialized HA/EGF mixture containing 2 μg of EGF and 0.4 mg of sodium hyaluronate). Animals were sacrificed on day 21 for further examinations.

RESULTS

The HA/EGF group showed visible improvement in hematuria with a significant reduction of red blood cells in the urine compared to the HA group. Histological examination revealed that HA/EGF treatment reversed the abnormalities developed in IC, including infiltration of inflammatory cells, irregular re-epithelialization, and fibrotic tissue. Moreover, HA/ EGF significantly reduced the levels of proinflammation cytokines (tumor necrosis factor-α, interleukin [IL]-6, and IL-1β) and substantially lowered the elevated oxidative stress biomarker malondialdehyde, yet restored the levels of antioxidant enzymes glutathione peroxidase and superoxide dismutase, with superior results than HA treatment. Cystometry studies indicated that HA/EGF significantly prolonged intercontraction interval and increased micturition volume.

CONCLUSION

HA/EGF has been demonstrated as a more effective treatment for enhancing the urothelium lining and reducing inflammatory changes to alleviate clinical symptoms associated with IC in rats, compared to HA alone.

The association between overactive bladder and systemic immunity-inflammation index: a cross-sectional study of NHANES 2005 to 2018

Current research indicate that inflammation is linked to the development of overactive bladder (OAB). The aim of this study was to examine the correlation between OAB and the systemic immunity-inflammation index (SII) in the USA. We analyzed data from 31,881 participants in the National Health and Nutrition Examination Survey 2005-2018. SII, calculated as platelet count × neutrophil count/lymphocyte count, was categorized into quartiles. OAB was defined by the presence of urge urinary incontinence and nocturia. Weighted logistic regression models were used to examine the independent relationship between SII and OAB, adjusting for demographic factors, kidney function, and diabetes status. The results showed that each tenfold increase in log-transformed SII was associated with an 18% higher odds of OAB (OR 1.18, 95% CI 1.08-1.28) in the fully adjusted model. Compared to the lowest SII quartile, the highest quartile had a 28% increased OAB risk (OR 1.28, 95% CI 1.12-1.47). The positive association between SII and OAB risk was consistently observed across subgroups stratified by age, sex, race, marital status, education, and poverty level. Our study reveals a positive correlation between SII levels and OAB, indicating that higher SII levels are associated with an increased likelihood of developing OAB.

The effect of myeloablative radiation on urinary bladder mast cells

Radiation-induced cystitis is an inflammatory condition affecting the urinary bladder, which can develop as a side effect of abdominopelvic radiotherapy, specifically external-beam radiation therapy or myeloablative radiotherapy. A possible involvement of mast cells in the pathophysiology of radiation-induced cystitis has been indicated in cases of external-beam radiation therapy; however, there is no evidence that these findings apply to the myeloablative aetiology. As such, this study investigated potential changes to urinary bladder mast cell prevalence when exposed to myeloablative radiation. Lethally irradiated C57BL/6J mice that received donor rescue bone marrow cells exhibited an increased mast cell frequency amongst host leukocytes 1 week following irradiation. By 4 weeks, no significant difference in either frequency or cell density was observed. However mast cell diameter was smaller, and a significant increase in mast cell number in the adventitia was observed. This study highlights that mast cells constitute a significant portion of the remaining host leukocyte population following radiation exposure, with changes to mast cell distribution and decreased cell diameter four weeks following radiation-induced injury.

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 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.

Animal models of interstitial cystitis/bladder pain syndrome

Interstitial Cystitis/Bladder Pain Syndrome (IC/BPS) is a chronic disorder characterized by pelvic and/or bladder pain, along with lower urinary tract symptoms that have a significant impact on an individual's quality of life. The diverse range of symptoms and underlying causes in IC/BPS patients pose a significant challenge for effective disease management and the development of new and effective treatments. To facilitate the development of innovative therapies for IC/BPS, numerous preclinical animal models have been developed, each focusing on distinct pathophysiological components such as localized urothelial permeability or inflammation, psychological stress, autoimmunity, and central sensitization. However, since the precise etiopathophysiology of IC/BPS remains undefined, these animal models have primarily aimed to replicate the key clinical symptoms of bladder hypersensitivity and pain to enhance the translatability of potential therapeutics. Several animal models have now been characterized to mimic the major symptoms of IC/BPS, and significant progress has been made in refining these models to induce chronic symptomatology that more closely resembles the IC/BPS phenotype. Nevertheless, it's important to note that no single model can fully replicate all aspects of the human disease. When selecting an appropriate model for preclinical therapeutic evaluation, consideration must be given to the specific pathology believed to underlie the development of IC/BPS symptoms in a particular patient group, as well as the type and severity of the model, its duration, and the proposed intervention's mechanism of action. Therefore, it is likely that different models will continue to be necessary for preclinical drug development, depending on the unique etiology of IC/BPS being investigated.

Current optimal pharmacologic therapies for overactive bladder

INTRODUCTION

Overactive bladder (OAB) is a common syndrome in adults. Current pharmacologic treatment includes antimuscarinic agents and β-3 adrenoceptor agonists. For non-responders to oral medication, intravesical injection of botulinum toxin A (BoNT-A) is an effective option. However, these treatments have potential adverse events and should be cautiously selected for appropriate patients. This review presents the recently published results of clinical trials and studies for patients with OAB and the underlying pathophysiology of OAB. Appropriate medical therapy based on pathophysiology of OAB is also presented.

AREAS COVERED

Literature search from Pubmed from 2001 to 2023 including clinical background, pharmacology, and clinical studies for OAB medications.

EXPERT OPINION

Treatment of OAB syndrome with any antimuscarinic or β-3 adrenoceptor agonist is feasible as a first-line approach. For patients with suboptimal therapeutic effect to full-dose antimuscarinics or mirabegron, combination with both drugs can improve efficacy. Intravesical BoNT-A 100-U injection provides therapeutic effects for refractory OAB. Patients who are refractory to initial pharmacotherapies should be investigated for the underlying pathophysiology; then an appropriate medication can be added, such as an α1-blocker or anti-inflammatory agents. Patient education about behavioral modification and therapies should always be provided with oral medication or BoNT-A injection for OAB patients.

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.

Cannabidiol as a Promising Therapeutic Option in IC/BPS: In Vitro Evaluation of Its Protective Effects against Inflammation and Oxidative Stress

Several animal studies have described the potential effect of cannabidiol (CBD) in alleviating the symptoms of interstitial cystitis/bladder pain syndrome (IC/BPS), a chronic inflammatory disease of the urinary bladder. However, the effects of CBD, its mechanism of action, and modulation of downstream signaling pathways in urothelial cells, the main effector cells in IC/BPS, have not been fully elucidated yet. Here, we investigated the effect of CBD against inflammation and oxidative stress in an in vitro model of IC/BPS comprised of TNFα-stimulated human urothelial cells SV-HUC1. Our results show that CBD treatment of urothelial cells significantly decreased TNFα-upregulated mRNA and protein expression of IL1α, IL8, CXCL1, and CXCL10, as well as attenuated NFκB phosphorylation. In addition, CBD treatment also diminished TNFα-driven cellular reactive oxygen species generation (ROS), by increasing the expression of the redox-sensitive transcription factor Nrf2, the antioxidant enzymes superoxide dismutase 1 and 2, and hem oxygenase 1. CBD-mediated effects in urothelial cells may occur by the activation of the PPARγ receptor since inhibition of PPARγ resulted in significantly diminished anti-inflammatory and antioxidant effects of CBD. Our observations provide new insights into the therapeutic potential of CBD through modulation of PPARγ/Nrf2/NFκB signaling pathways, which could be further exploited in the treatment of IC/BPS.

Involvement of Mast-Cell-Tryptase- and Protease-Activated Receptor 2-Mediated Signaling and Urothelial Barrier Dysfunction with Reduced Uroplakin II Expression in Bladder Hyperactivity Induced by Chronic Bladder Ischemia in the Rat

We aimed to investigate the relationship between mast cell (MC) infiltration into the bladder with urothelial barrier dysfunction and bladder hyperactivity in a chronic bladder ischemia (CBI) rat model. We compared CBI rats (CBI group; n = 10) with normal rats (control group; n = 10). We measured the expression of mast cell tryptase (MCT) and protease-activated receptor 2 (PAR2), which are correlated with C fiber activation via MCT, and Uroplakins (UP Ia, Ib, II and III), which are critical to urothelial barrier function, via Western blotting. The effects of FSLLRY-NH2, a PAR2 antagonist, administered intravenously, on the bladder function of CBI rats were evaluated with a cystometrogram. In the CBI group, the MC number in the bladder was significantly greater (p = 0.03), and the expression of MCT (p = 0.02) and PAR2 (p = 0.02) was significantly increased compared to that of the control group. The 10 μg/kg FSLLRY-NH2 injection significantly increased the micturition interval of CBI rats (p = 0.03). The percentage of UP-II-positive cells on the urothelium with immunohistochemical staining was significantly lower in the CBI group than in the control group (p < 0.01). Chronic ischemia induces urothelial barrier dysfunction via impairing UP II, consequently inducing MC infiltration into the bladder wall and increased PAR2 expression. PAR2 activation by MCT may contribute to bladder hyperactivity.

Liposome-Encapsulated Botulinum Toxin A in Treatment of Functional Bladder Disorders

Botulinum toxin A (BoNT-A) intravesical injections have been used to treat patients with refractory functional bladder disorders such as overactive bladder (OAB) and interstitial cystitis/bladder pain syndrome (IC/BPS), but the risk of adverse events and the need for repeated injections continue to prevent widespread application of this treatment. Liposomes are vesicles that comprise concentric phospholipid layers and an aqueous core; their flexible compositions enable them to adsorb and fuse with cell membranes and to deliver drugs or proteins into cells. Therefore, liposomes have been considered as promising vehicles for the less invasive delivery of BoNT-A. In previous placebo-controlled trials including patients with OAB refractory to medical treatment, it was shown that liposomal BoNT-A could significantly decrease the frequency and urgency of urination. In patients with IC/BPS, it was shown that liposomal BoNT-A could also improve bladder pain, but the therapeutic efficacy was not superior to that of the placebo. As the therapeutic mechanisms of BoNT-A include the decreased expression of nerve growth factors, P2X3 receptors, and vanilloid receptors on C-fibers, liposomal BoNT-A might play a more promising role in the treatment of bladder oversensitivity. This article features the contemporary literature regarding BoNT-A, liposomes, and liposomal BoNT-A treatment for functional bladder disorders and potential clinical applications in the future.

Current Understanding of the Pathophysiology and Novel Treatments of Interstitial Cystitis/Bladder Pain Syndrome

The pathophysiology of interstitial cystitis/bladder pain syndrome (IC/BPS) is multifactorial. Identifying the clinical characteristics and cystoscopic findings of bladder-centered IC/BPS facilitates optimal treatment strategies targeting the diseased urinary bladder. Patients with Hunner’s lesion (HIC) and without Hunner’s lesion (NHIC) should be treated differently. Based on the histopathological findings, NHIC can be treated with intravesical instillation of urothelial protective agents, such as hyaluronic acid, to cover the urothelial defects. In non-responders, chronic inflammation and higher urothelial dysfunction can be treated with intravesical botulinum toxin A injection, platelet-rich plasma injection, or low-energy shock wave treatment to reduce inflammation, increase tissue regeneration, and improve the urothelial barrier. Patients with HIC should be treated with electrocauterization first; augmentation enterocystoplasty should only be used in end-stage HIC when the contracted bladder is refractory to other treatments. The antiviral agent, valacyclovir, can be used in patients with HIC, small bladder capacity, and high-grade glomerulations. In addition, behavioral modification is always recommended from the beginning of treatment. Treatment with cognitive behavioral therapy interventions in combination with bladder therapy can reduce anxiety and improve treatment outcomes. Herein, recent advances in the pathophysiology and novel treatments for IC/BPS are reviewed.

Comprehensive transcriptome profiling of urothelial cells following TNFα stimulation in an in vitro interstitial cystitis/bladder pain syndrome model

Urothelial cells of the urinary bladder play a critical role in the development and progression of interstitial cystitis/bladder pain syndrome (IC/BPS), a chronic and debilitating inflammatory disease. Given the lack of data on the exact phenotype and function of urothelial cells in an inflammatory setting (as in IC/BPS), we performed the first in-depth characterization of these cells using RNA sequencing, qPCR, ELISA, Western blot, and immunofluorescence. After TNFα stimulation, urothelial cells in the in vitro model of IC/BPS showed marked upregulation of several proinflammatory mediators, such as SAA, C3, IFNGR1, IL1α, IL1β, IL8, IL23A, IL32, CXCL1, CXCL5, CXCL10, CXCL11, TNFAIPR, TNFRSF1B, and BIRC3, involved in processes and pathways of innate immunity, including granulocyte migration and chemotaxis, inflammatory response, and complement activation, as well as TLR-, NOD-like receptor- and NFkB-signaling pathways, suggesting their active role in shaping the local immune response of the bladder. Our study demonstrates that the TNFα-stimulated urothelial cells recapitulate key observations found in the bladders of patients with IC/BPS, underpinning their utility as a suitable in vitro model for understanding IC/BPS mechanisms and confirming the role of TNFα signaling as an important component of the associated pathology. The present study also identifies novel upregulated gene targets of TNFα in urothelial cells, including genes encoding the acute phase protein SAA, complement component C3, and the cytokine receptor IFNGR1, which could be exploited as therapeutic targets of IC/BPS. Altogether, our study provides a reference database of the phenotype of urothelial cells in an inflammatory environment that will not only increase our knowledge of their role in IC/BPS, but also advance our understanding of how urothelial cells shape tissue immunity in the bladder.

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.

[Bladder pain syndrome: Long-term results (15 years) of a single-center experience]

INTRODUCTION

The management of bladder pain syndrome (BPS) in our center is standardized although there is no real consensus and recommendations. The objectives of our study were to assess the effectiveness of the treatment offered and to identify predictive factors of response to treatment.

PATIENTS AND METHODS

Single-center retrospective study including all patients with BPS. Patient and outcome measures included ICSI and ICPI scores, daytime voiding interval (DVI), nocturnal pollakiuria (NPK), and subjective satisfaction (SS). The complete care protocol (CCP) was based on a hydrodistension test followed by a cimetidine treatment then by 6 instillations of dimethyl sulfoxide followed by a maintenance treatment with pentosan polysulfate. The main objective of our study was the patient's SS at 3months and at medium term. One of the secondary objectives was to study the predictive factors of response to treatment.

OUTCOMES

From 2002 to 2019, 211 patients (90.5% women) were treated for BPS. Sixty-nine patients (35%) underwent the CCP that provided significant improvement in ICSI, ICPI, DVI and NPK and SS of 52.2%.). In the medium term, 149 patients were reassessed with a median follow-up of 99.6months (±3.6): 71.8% were satisfied and 54.2% were no longer receiving treatment. Among the 49 patients who initially received PSC, 74% were satisfied at 89.8 months of median follow-up (±2.9). In multivariate analysis, patients with a pain perception disorder (HR=0.17 IC95=0.05-0.52; P=0.002) or consuming anxiolytics (HR=0.3; IC95=0.13-0.69; P=0.004) had a statistically greater risk of not being satisfied.

CONCLUSION

In our study, the CCP achieves subjective medium-term satisfaction in nearly 75% of patients with BPS. These data deserve to be confirmed on a larger scale in a prospective protocol.

LEVEL OF EVIDENCE: 4

Changes in the Ultrastructure of the Bladder Urothelium in Patients with Interstitial Cystitis after Intravesical Injections of Platelet-Rich Plasma

Urothelial dysfunction is considered a key pathological mechanism of interstitial cystitis/bladder pain syndrome (IC/BPS). Intravesical platelet-rich plasma (PRP) injections might be effective for treating IC/BPS. This prospective study investigated the changes in electron microscopic findings among IC/BPS patients after intravesical PRP injections. Twenty-six patients with refractory non-ulcer IC/BPS underwent monthly intravesical PRP injections for 4 months. Changes in clinical symptom scores and video urodynamic study parameters were assessed from baseline to after the PRP injections. A post-treatment Global Response Assessment (GRA) score ≥ 2 was considered a successful outcome. The mean GRA score was significantly higher after 4 PRP injections than at baseline. Approximately 42% of patients experienced successful outcomes after PRP treatment. Urothelial ultrastructural defects showed no significant differences between baseline and after the PRP injections. However, patients showed variable improvements in different urothelial defects (grade improvements: urothelium cell layers, 31%; umbrella cell integrity, 42%; umbrella cell surface uroplakin plaque, 54%; tight junctions between adjacent umbrella cells, 46%; lysed organelles, 58%; inflammatory cell infiltration, 31%). Patients with successful treatment outcomes showed significant improvements in urothelial tight junction defects. Repeated intravesical PRP injections are effective for improving IC/BPS symptoms as they promote urothelial ultrastructural defect recovery.

Molecular Pathophysiology and Potential Therapeutic Strategies of Ketamine-Related Cystitis

Ketamine was first synthesized as a clinical medicine for anesthesia in 1970. It has been used as a recreational drug because of its low cost and hallucination effect in the past decade. Part of ketamine abusers may experience ketamine-related cystitis (KC) and suffer from lower urinary tract symptoms, including urinary frequency, urgency, and severe bladder pain. As the disease progression, a contracted bladder, petechial hemorrhage of the bladder mucosa, and ureteral stricture with hydronephrosis may occur. The pathophysiology of KC is still uncertain, although several hypotheses have been raised. Cessation of ketamine abuse is critical for the management of KC to prevent progressive disease, and effective treatment has not been established. Research has provided some theoretical bases for developing in vitro experiments, animal models, and clinical trials. This review summarized evidence of molecular mechanisms of KC and potential treatment strategies for KC. Further basic and clinical studies will help us better understand the mechanism and develop an effective treatment for KC.

Low-Energy Shock Wave Plus Intravesical Instillation of Botulinum Toxin A for Interstitial Cystitis/Bladder Pain Syndrome: Pathophysiology and Preliminary Result of a Novel Minimally Invasive Treatment

Low-energy shock wave (LESW) therapy is known to facilitate tissue regeneration with analgesic and anti-inflammatory effects. LESW treatment has been demonstrated to be effective in treating chronic prostatitis and pelvic pain syndrome as well as overactive bladder, and it has a potential effect on interstitial cystitis/bladder pain syndrome (IC/BPS) in humans. LESW reduces pain behavior, downregulates nerve growth factor expression, and suppresses bladder overactivity by decreasing the expression of inflammatory proteins. Previous rat IC models have shown that LESW can increase urothelial permeability, facilitate intravesical delivery of botulinum toxin A (BoNT-A), and block acetic acid-induced hyperactive bladder, suggesting that LESW might be a potential therapeutic module for relieving bladder inflammatory conditions, such as bladder oversensitivity, IC/BPS, and overactive bladder. A recent clinical trial showed that LESW monotherapy was associated with a significant reduction in pain scores and IC symptoms. BoNT-A detrusor injection or liposome-encapsulated BoNT-A instillation could also inhibit inflammation and improve IC symptoms. However, BoNT-A injection requires anesthesia and certain complications might occur. Our preliminary study using LESW plus intravesical BoNT-A instillation every week demonstrated an improvement in global response assessment without any adverse events. Moreover, an immunohistochemistry study revealed the presence of cleaved SNAP25 protein in the suburothelium of IC bladder tissue, indicating that BoNT-A could penetrate across the urothelial barrier after application of LESW. These results provide evidence for the efficacy and safety of this novel IC/BPS treatment by LESW plus BoNT-A instillation, without anesthesia, and no bladder injection. This article reviews the current evidence on LESW and LESW plus intravesical therapeutic agents on bladder disorders and the pathophysiology and pharmacological mechanism of this novel, minimally invasive treatment model for IC/BPS.

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

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

Suppression of Inflammatory and Fibrotic Signals by Cinnamon (Cinnamomum cassia) and Cinnamaldehyde in Cyclophosphamide-Induced Overactive Bladder in Mice

Cinnamon (Cinnamomum cassia) is a well-known traditional Chinese medicine used to treat nocturia by tonifying and warming the kidney. Our recent clinical study found that overactive bladder (OAB) patients treated with cinnamon powder (CNP) patches exhibited significantly ameliorated OAB symptoms without significant side effects, but the mechanism of action is unclear. To explore the beneficial effects and action mechanisms of CNP and its major active component cinnamaldehyde (CNA) in an OAB-related murine model, cyclophosphamide- (CYP-) induced OAB injury was performed on male ICR mice in the presence or absence of CNP and CNA, as well as solifenacin, a clinical drug for OAB as a reference. Twenty-four-hour micturition patterns (frequency of urination and volume of urine per time), as well as histopathological examination, immunohistochemistry (IHC), and Western blotting of the bladder, were analyzed for mechanism elucidation. Administration of CYP (300 mg/kg, i.p.) induced typical OAB pathophysiological changes, including increased frequency of urination and reduced volume of urine. CYP-induced mice displayed strong edema of the bladder and hemorrhagic cystitis, accompanied by loss of normal corrugated folds and decreased muscarinic receptors (M2/M3) in the urothelium, and disordered/broken structures of the lamina propria and detrusor. These changes were correlated with increased leukocyte (CD11b) infiltration colocalized with inflammatory (pp65 NFκB, macrophage migration inhibitory factor (MIF)/Toll-like receptor 4 (TLR4)) and fibrotic (stem cell factor (SCF)/c-Kit, α-smooth muscle actin (α-SMA)/β-catenin) signals. Treatment with CNP (600 mg/kg, p.o.) and CNA (10–50 mg/kg, p.o.), but not solifenacin (50 mg/kg), 30 min after CYP induction significantly ameliorated CYP-induced dysfunction in micturition patterns and pathophysiological changes. CNP and CNA further suppressed MIF/TLR4-associated inflammatory and SCF/c-Kit-related fibrotic signaling pathways. Our findings indicate that suppression of inflammatory and fibrotic signals contributes to the crucial mechanism in the improvement of CYP-induced OAB by CNP and CNA.

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.

Functional and histologic imaging of urinary bladder wall after exposure to psychological stress and protamine sulfate

To quantify the urinary bladder wall T1 relaxation time (T1) before and after the instillation contrast mixture in rats previously subjected to water avoidance stress (WAS) and/or acute exposure to protamine sulfate (PS). Female Wistar rats were randomized to receive either sham (control) or 1 h of WAS for ten consecutive days before the evaluation of nocturnal urination pattern in metabolic cages. T1 mapping of urinary bladder wall at 9.4 T was performed pre- and post- instillation of 4 mM Gadobutrol in a mixture with 5 mM Ferumoxytol. Subsequently, either T1 mapping was repeated after brief intravesical PS exposure or the animals were sacrificed for histology and analyzing the mucosal levels of mRNA. Compared to the control group, WAS exposure decreased the single void urine volume and shortened the post-contrast T1 relaxation time of mucosa- used to compute relatively higher ingress of instilled Gadobutrol. Compromised permeability in WAS group was corroborated by the urothelial denudation, edema and ZO-1 downregulation. PS exposure doubled the baseline ingress of Gadobutrol in both groups. These findings confirm that psychological stress compromises the paracellular permeability of bladder mucosa and its non-invasive assay with MRI was validated by PS exposure.

Assessment of bladder function for stabilizing urinary volume overnight with recording of brain waves (ABSORB study)

OBJECTIVES

The bladder urothelium is not always impermeable. During sleep, the bladder might absorb urine in healthy individuals who sleep through the night. This study aimed to determine whether the bladder absorbs urine by using a method other than ultrasonic scanning and to simultaneously evaluate sleeping conditions.

METHODS

Eleven participants (five males, six females) aged 20 to 49 years without lower urinary tract symptoms or urination while sleeping were enrolled. Bladder volume was estimated by studying the relationship between dilution and absorbance of indigo carmine dissolved in urine. A 12F Foley catheter was inserted into the bladder before sleep. Urine samples (5 mL) were extracted at 2, 3, 4, 5, and 6 am sleep stages were monitored with a single-channel portable electroencephalograph device.

RESULTS

The estimated bladder volume at 6 am and voided volume immediately after rising were significantly correlated (Spearman's ρ = 0.62, P = .046). Eight participants (three males, five females) showed an absorption pattern of the estimated bladder volume change. In a male participant, the blue dye's strength gradually decreased until 4 am (estimated 859 mL) and increased from 5 am (estimated 455 mL). In another, the blue dye's strength increased at 4 am (estimated 449 mL) vs at 3 am (estimated 757 mL). In all participants, electroencephalograph data demonstrated that sleep was maintained despite having a full bladder.

CONCLUSIONS

The bladder absorbs urine and maintains an approximate volume of functional bladder capacity during sleep to avoid incontinence and maintain sleep in adults due to an urge to void urine during the sleep cycle.

Difference in electron microscopic findings among interstitial cystitis/bladder pain syndrome with distinct clinical and cystoscopic characteristics

Urothelial dysfunction may be a key pathomechanism underlying interstitial cystitis/bladder pain syndrome (IC/BPS). We therefore examined if clinical severity is associated with the extent of urothelial damage as revealed by electron microscopic (EM) analysis of biopsy tissue. One hundred IC/BPS patients were enrolled and 24 patients with stress urinary incontinence served as controls. Clinical symptoms were evaluated by visual analog scale pain score and O’Leary-Sant Symptom score. Bladder biopsies were obtained following cystoscopic hydrodistention. The presence of Hunner’s lesions and glomerulation grade after hydrodistention were recorded and patients classified as Hunner-type IC (HIC) or non-Hunner-type IC (NHIC). HIC patients exhibited more severe defects in urothelium cell layers, including greater loss of umbrella cells, umbrella cell surface uroplakin plaque, and tight junctions between adjacent umbrella cells, compared to control and NHIC groups (all p < 0.05). Both NHIC and HIC groups demonstrated more severe lamina propria inflammatory cell infiltration than controls (p = 0.011, p < 0.001, respectively). O’Leary-Sant Symptom scores were significantly higher among patients with more severe urothelial defects (p = 0.030). Thus, urothelium cell layer defects on EM are associated with greater clinical symptom severity.

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.

Decreased urothelial cytoskeleton and cell proliferation protein expression suggest interstitial cystitis/bladder pain syndrome patients with Hunner's lesion and grade 3 glomerulation might be different from other types of patients

OBJECTIVES

To explore the expression of cytoskeletal and cell proliferation proteins in urothelial cells of patients diagnosed with various clinical subtypes of interstitial cystitis/bladder pain syndrome.

METHODS

Biopsy specimens from 85 interstitial cystitis/bladder pain syndrome patients were classified according to findings on cystoscopy. Cytokeratins and cell proliferation proteins detected in the specimens were evaluated with immunofluorescence staining and quantified with western blotting. A total of 22 patients diagnosed with pure stress urinary incontinence were enrolled as controls.

RESULTS

Interstitial cystitis/bladder pain syndrome patients with Hunner's lesion and with grade 3 glomerulation hemorrhage had smaller bladder capacities than the other interstitial cystitis/bladder pain syndrome patients without Hunner's lesion. Diminished expression of CK14, CK20, cell proliferation protein tumor protein 63, sonic hedgehog, and fibroblast growth factor receptors 3 and 4, and increased expression of CK5 and BCL2-associated X protein were observed in biopsy specimens from patients with Hunner's lesion compared with those from patients without Hunner's lesion and controls. In the patients with grade 3 glomerulation hemorrhage, lower expression levels of urothelial CK20, tumor protein 63 and fibroblast growth factor receptor 4, and lower expression of CK5 and BCL2-associated X protein were detected compared with other types of NHIC.

CONCLUSION

A diminished expression of proliferation proteins tumor protein 63 and the mature urothelium marker CK20, and increased expression of the immature marker CK5 in specimens from both Hunner's lesion and grade 3 glomerulation hemorrhage patients can be observed. The urothelium of patients with interstitial cystitis/bladder pain syndrome might be in a state of persistent or chronic injury that could relate to the limited expression of cell proliferation proteins.

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.

Asiatic Acid, a Natural Compound that Exerts Beneficial Effects on the Cystometric and Biochemical Parameters in the Retinyl Acetate-Induced Model of Detrusor Overactivity

Scientists have been constantly looking for new synthetic and natural compounds that could have beneficial effects in bladder overactivity. Our attention was drawn by asiatic acid that influences a number of molecules and signaling pathways relevant for the proper functioning of the urinary tracts in humans. In the present project we wanted to check whether asiatic acid would have positive effects in the confirmed animal model of detrusor overactivity (DO) and whether it would affect the bladder blood flow, urothelium thickness, inflammatory and oxidative stress markers, neurotrophic and growth factors, and other parameters important for the activity of the urinary bladder. The outcomes of our study showed that a 14-day administration of asiatic acid (30 mg/kg/day) by oral gavage normalizes the cystometric parameters corresponding to DO and reduces the accompanying oxidative stress (measured by the levels of malondialdehyde–61,344 ± 24,908 pg/ml vs. 33,668 ± 5,071 pg/ml, 3-nitrotyrosine–64,615 ± 25,433 pg/ml vs. 6,563 ± 1,736 pg/ml, and NOS2–2,506 ± 411.7 vs. 3,824 ± 470.1 pg/ml). Moreover, it decreases the urinary secretion of neurotrophins (BDNF–304.4 ± 33.21 pg/ml vs. 119.3 ± 11.49 pg/ml and NGF–205.5 ± 18.50 vs. 109.7 ± 15.94 pg/ml) and prevents the changes in a range of biomarkers indicating the dysfunction of the urinary bladder, CGRP (421.1 ± 56.64 vs. 108.1 ± 11.73 pg/ml), E-Cadherin (773.5 ± 177.5 pg/ml vs. 1,560 ± 154.5 pg/ml), OCT3 (3,943 ± 814.6 vs. 1,018 ± 97.07 pg/ml), SNAP-23 (6,763 ± 808.9 pg/ml vs. 3,455 ± 554.5 pg/ml), SNAP-25 (2,038 ± 162.7 pg/ml vs. 833.3 ± 65.48), substance P (171.7 ± 16.86 pg/ml vs. 65.07 ± 8.250 pg/ml), SV2A (1,927 ± 175.3 pg/ml vs. 1,154 ± 254.9 pg/ml), tight junction protein 1 (360.1 ± 95.05 pg/ml vs. 563.4 ± 65.43 pg/ml), VAChT (16,470 ± 2,419 pg/ml vs. 7,072 ± 1,339 pg/ml), VEGFA (318.3 ± 37.89 pg/ml vs. 201.5 ± 22.91 pg/ml). The mentioned parameters are associated with smooth muscle contractions, urothelial barrier, transportation and release of transmitters, or bladder compensation. Thus, the presented findings allow to suggest a possible future role of asiatic acid in the prevention of conditions accompanied by DO, such as overactive bladder.

Urine biomarkers in ESSIC type 2 interstitial cystitis/bladder pain syndrome and overactive bladder with developing a novel diagnostic algorithm

This study aimed to investigate the diagnostic values of urine cytokines in interstitial cystitis/bladder pain syndrome (IC/BPS) and overactive bladder (OAB) patients, and to develop a novel diagnostic algorithm. Urine samples were collected from 40 IC/BPS, 40 OAB patients, and 30 controls. Commercially available multiplex immunoassays were used to analyze 31 targeted cytokines. Urine cytokine profiles were significantly different among study groups and controls. MIP-1β showed the highest sensitivity (92.2%) for identifying diseased study patients from controls. The cytokines with high diagnostic values for distinguishing between IC and OAB included IL-10, RANTES, eotaxin, CXCL10, IL-12p70, NGF, IL-6, IL-17A, MCP-1, and IL-1RA. The diagnostic algorithm was subsequently developed according to the diagnostic values obtained. MIP-1β was selected for the initial screening test to diagnose diseased patients and controls with diagnostic rates of 81.6% and 68.4%, respectively. As confirmation tests for IC/BPS, the diagnostic rates of eotaxin, CXCL10, and RANTES were 73.3%, 72.7%, and 69.7%, respectively. As the confirmation test for OAB, the diagnostic rate of IL-10 was 60%. Urine cytokine profiles of IC/BPS and OAB patients differed from those of controls and might be useful as biomarkers for diagnosis. A novel pilot diagnostic algorithm was developed based on these profiles.

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

INTRODUCTION AND HYPOTHESIS

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

METHODS

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

RESULTS

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

CONCLUSIONS

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

Clinical Correlation Between Overactive Bladder and Allergy in Children

BACKGROUND

The International Children's Continence Society defines overactive bladder (OAB) as a clinical syndrome characterized by urgency of urination usually accompanied by frequent urination and nocturia symptoms. This study aims to explore the correlation between overactive bladder (OAB) and allergy in children.

METHOD

The clinical characteristics of 918 patients diagnosed with OAB from January 2020 to March 2021 were retrospectively analyzed. Risk factors for OAB were analyzed using logistic regression analysis, and the effect of desloratadine in the treatment of OAB was evaluated.

RESULTS

The incidence of allergic cough or allergic rhinitis in the mild OAB group was higher than the moderate-severe group. Urodynamics demonstrated that the proportion of patients with a sensitive bladder in the overactive detrusor group was significantly higher than the non-overactive detrusor group. The effective rate of treatment of OAB in patients complicated with allergies and taking desloratadine was 90.14%, which was significantly higher than in patients who were not taking desloratadine, and blood IgE level was a risk factor of ineffective treatment with desloratadine.

CONCLUSION

OAB is correlated with allergies in children, and desloratadine can effectively improve OAB symptoms.

Urothelial health after platelet-rich plasma injection in intractable recurrent urinary tract infection: Improved cell proliferation, cytoskeleton, and barrier function protein expression

OBJECTIVE

This clinical study used autologous intravesical platelet-rich plasma (PRP) injections to treat patients with recurrent urinary tract infection (rUTI). Changes in urothelial proliferation, cytoskeleton, and barrier function protein expression after treatment were investigated.

MATERIALS

All patients underwent 4-monthly intravesical PRP injections with 1-year follow-up. Successful treatment was defined as ≤2 UTI episodes within the preceding 1 year. Bladder biopsies were performed at the first and fourth PRP injection, and specimens were investigated by Western blot for the proteins sonic hedgehog (Shh), CD34, cytokeratin 5 (CK5), CK14, CK20, zonula occludens-1 (ZO-1), E-cadherin, inflammatory proteins tryptase and p38, apoptotic protein BAX (BCL2-associated X protein) and caspase-3, functional proteins M2 (muscarinic receptor 2) and M3, and beta-adrenoceptor-3, with glyceraldehyde phosphate dehydrogenase used as normalizing protein for quantification.

RESULTS

The study enrolled 22 patients with rUTI and 17 controls, with successful outcome in 14 of 22 (63.6%) patients. Compared with controls, Western blot quantification results showed that rUTI patients had lower CD34, CK20, M3, and ZO-1, but higher CK5, BAX, and caspase-3 at baseline. The reduced CD34, CK20, M2, and M3 expressions at baseline were significantly increased after repeat PRP injections. Patients with a successful outcome had significant increase of CD34, Shh, CK20, M2, and M3 expressions after PRP injections.

CONCLUSION

Intravesical PRP repeat injections improve the urothelial cell proliferation and increase the CK 20 expression in umbrella cells. PRP repeat injections have a beneficial effect on bladder urothelium-associated changes in rUTI. Thus, PRP injection may restore urothelial health and prevent UTI recurrence in intractable rUTI.

Deficits of urothelial cell proliferation, cytoskeleton, and barrier function protein expressions in patients with recurrent and persistent urinary tract infections

OBJECTIVES

Recurrent urinary tract infection (rUTI) is a common infectious disease in women. This study investigated the urothelial cell proliferation, the cytoskeleton, barrier proteins, and inflammatory protein expression in women with rUTIs.

METHODS

Female patients with recurrent or persistent UTIs were recruited. Bladder mucosal specimens were investigated by Western blot and immunohistochemical staining for the urothelial cytoskeleton proteins cytokeratin 5 (CK5), CK14, and CK20; proteins involved in cellular proliferation, including CD34, sonic hedgehog (SHH), and tumor protein 63 (TP63); barrier proteins zonula occludens 1 (ZO-1) and E-cadherin; inflammatory proteins p38 and tryptase; and proapoptotic proteins Bcl2-associated agonist of cell death protein (BAD), Bcl2-associated X protein (BAX), and caspase-3. Women with stress urinary incontinence without bladder symptoms served as controls. Bladder specimens from 18 recurrent UTI patients with rUTIs and 12 persistent UTIs, and 17 controls were analyzed, and protein expressions were compared between the three groups.

RESULTS

Cell proliferation protein expression for CD34, SHH, and TP63 was significantly lower in the urothelium of patients with rUTIs than in controls. Expression of CK5 increased, whereas CK20 decreased significantly in rUTIs compared with those of controls. Apoptotic proteins BAD, BAX, and caspase-3 were significantly higher in patients with rUTIs. However, barrier proteins ZO-1 and E-cadherin, and tryptase were not significantly lower in patients with rUTIs.

CONCLUSION

Deficits in expression of proteins involved in urothelial cell proliferation, cytoskeleton, and barrier function were noted in patients with rUTIs. These urothelial deficits may be due to deficient proliferation and differentiation resulting in inadequate urothelial barrier function and further in rUTIs.

Virtual measurements of paracellular permeability and chronic inflammation via color coded pixel-wise T1 mapping

To assess whether quantitative T₁ relaxometry can measure permeability, chronic inflammation and mural thickening of mouse bladder wall. Adult female C57BL6 mice unexposed to radiation (controls) or 40 wk postirradiation of 10 Gy were scanned at 9.4 T before and after instillation (0.1 mL) of aqueous, novel contrast mixture (NCM) containing 4 mM gadobutrol and 5 mM ferumoxytol. Rapid acquisition with refocused echo (RARE) sequence was used with variable repetition times (TR). Pixel-wise maps of T₁ relaxation times for the segmented bladder wall layers were generated from voxel-wise, nonlinear least square data fitting of TR-dependent signal intensity acquired with TR array of 0.4-10 s followed by the histology of harvested bladder. Significant differences between precontrast and postcontrast T₁ (ΔT₁) were noted in urothelium and lamina propria of both groups but only in detrusor of irradiated group (P < 0.001; 2-way ANOVA). Nearly twofold higher gadobutrol permeability (550 ± 73 vs. 294 ± 160 μM; P < 0.01) derived as per 1/ΔT₁ = r1. [C] in urothelium of irradiated group. Inflammation and bladder wall thickening (0.75 ± 0. vs. 0.44 ± 0.08 mm; P < 0.001) predicted by MRI was subsequently confirmed by histology and altered expression of CD45 and zonula occludens-1 (ZO-1) relative to controls. NCM enhanced MRI relies on the retention of large molecular weight ferumoxytol in lumen for negative contrast, while permeation of the non-ionic, small molecular weight gadobutrol through ZO-1 generates positive contrast in bladder wall for virtual measurement of paracellular permeability and assessment of chronic inflammation in thin and distensible bladder wall, which is also defined by its variable shape and location within pelvis.

Recurrent urinary tract infection in women and overactive bladder - Is there a relationship?

Overactive bladder (OAB) in women has similar symptomatology with other common urologic diseases such as recurrent urinary tract infection (UTI). Recent evidence showed that chronic low-grade bacterial bladder colonization might exacerbate OAB symptoms and could be the etiology of recurrent UTI. The high prevalence of lower urinary tract dysfunction is associated with OAB. Women with urgency urinary incontinence refractory to antimuscarinic therapy had more bacteria and a more diverse urinary microbiome. The bacterial reside in the superficial urothelial cells to form intracellular bacterial community and outbreak when the host innate immunity is low. Women with recurrent UTI are found to have highly prevalent voiding dysfunction and detrusor overactivity. These functional abnormalities will further damage the urothelial barrier integrity and create vulnerable to uropathogen invasion. The defective urinary microbiota is less common in women with recurrent UTI, suggesting that the normal flora in the urine might inhibit uropathogen growth and invasion. The defective urothelial barrier function, deficient basal proliferation, and deficient maturation might be owing to chronic suburothelial inflammation, resulting in activation of sensory nerves (causing OAB) and failure elimination of intracellular bacterial communities (causing recurrent UTI). Precision diagnosis and multidisciplinary treatment of the underlying pathophysiology of OAB and recurrent UTI is necessary.

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.

Effect of Botulinum Toxin A on Bladder Pain-Molecular Evidence and Animal Studies

Botulinum toxin A (BTX-A) is a powerful neurotoxin with long-lasting activity that blocks muscle contractions. In addition to effects on neuromuscular junctions, BTX-A also plays a role in sensory feedback loops, suggesting the potentiality for pain relief. Although the only approved indications for BTX-A in the bladder are neurogenic detrusor overactivity and refractory overactive bladder, BTX-A injections to treat bladder pain refractory to conventional therapies are also recommended. The mechanism of BTX-A activity in bladder pain is complex, with several hypotheses proposed in recent studies. Here we comprehensively reviewed properties of BTX-A in peripheral afferent and efferent nerves, the inhibition of nociceptive neurotransmitter release, the reduction of stretch-related visceral pain, and its anti-inflammatory effects on the bladder urothelium. Studies have also revealed possible effects of BTX-A in the human brain. However, further basic and clinical studies are warranted to provide solid evidence-based support in using BTX-A to treat bladder pain.

Predictive Factors for a Satisfactory Treatment Outcome with Intravesical Botulinum Toxin A Injection in Patients with Interstitial Cystitis/Bladder Pain Syndrome

A botulinum toxin A (BoNT-A) intravesical injection can improve the symptoms of interstitial cystitis/bladder pain syndrome (IC/BPS). Patients with IC/BPS have different clinical characteristics, urodynamic features, and cystoscopic findings. This study assessed the treatment outcomes of a BoNT-A intravesical injection and aimed to identify the predictive factors of a satisfactory outcome. This retrospective study included IC/BPS patients treated with 100 U BoNT-A. The treatment outcomes were assessed by global response assessment (GRA) at 6 months. We classified patients according to different clinical, urodynamic, and cystoscopic characteristics and evaluated the treatment outcomes and predictive factors. A total of 238 patients were included. Among these patients, 113 (47.5%) had a satisfactory outcome (GRA ≥ 2) and 125 (52.5%) had an unsatisfactory outcome. Improvements in the IC symptom score, IC problem score, O'Leary-Sant symptom score, and visual analog scale score for pain were significantly greater in patients with a satisfactory outcome than in patients with an unsatisfactory outcome (all p = 0.000). The IC disease duration and maximal bladder capacity (MBC) were significantly different between patients with and without a satisfactory outcome. Multivariate analysis revealed that only the MBC was a predictor for a satisfactory outcome. Patients with a MBC of ≥760 mL and glomerulations of 0/1 (58.7%) or glomerulations of 2/3 (75.0%) frequently had a satisfactory outcome. We found that BoNT-A intravesical injection can effectively improve symptoms among patients with IC/BPS, with a remarkable reduction in bladder pain. A MBC of ≥760 mL is a predictive factor for a satisfactory treatment outcome.

Micronized Palmitoylethanolamide-Polydatin Reduces the Painful Symptomatology in Patients with Interstitial Cystitis/Bladder Pain Syndrome

Aims

To assess the efficacy of a micronized-palmitoylethanolamide-polydatin (m-PEA-Pol) based product on chronic pelvic pain and severity of other symptoms in interstitial cystitis/bladder pain syndrome (IC/BPS) patients refractory to conventional therapies.

Methods

A pilot, open-label bicentric study was carried out involving 32 IC/BPS patients. Chronic, oral m-PEA-Pol treatment lasted 6 months. Bladder pain was evaluated using the visual analog scale, while changes from baseline in other urinary symptoms were evaluated by means of the O'Leary-Sant Interstitial Cystitis Symptom and Problem Index and the Pelvic Pain and Urgency/Frequency (PUF) symptom scale questionnaires. The generalized linear mixed model was used to evaluate significant mean changes across time.

Results

A significant and progressive reduction of pain intensity was observed during m-PEA-Pol treatment (p < 0.0001 for reduction over time). The effect was associated with a reduction in severity of patients' symptoms evaluated with the O'Leary-Sant questionnaire (p=0.0110 and p=0.0014 for cystitis symptoms and problem mean scores, respectively) and the PUF scale (p=0.0163 and p=0.0005 for symptom and bother mean scores, respectively). m-PEA-Pol therapy elicited a significant reduction over time in the urinary frequency evaluated with voiding diary (p=0.0005) and a small but not significant improvement of bladder capacity.

Conclusions

These data highlight the potential benefit of m-PEA-Pol in patients with rare pathology such as IC/BPS and confirm the good safety profile of micronized PEA-based products.

Single-Cell Transcriptomic Map of the Human and Mouse Bladders

BACKGROUND

Having a comprehensive map of the cellular anatomy of the normal human bladder is vital to understanding the cellular origins of benign bladder disease and bladder cancer.

METHODS

We used single-cell RNA sequencing (scRNA-seq) of 12,423 cells from healthy human bladder tissue samples taken from patients with bladder cancer and 12,884 cells from mouse bladders to classify bladder cell types and their underlying functions.

RESULTS

We created a single-cell transcriptomic map of human and mouse bladders, including 16 clusters of human bladder cells and 15 clusters of mouse bladder cells. The homology and heterogeneity of human and mouse bladder cell types were compared and both conservative and heterogeneous aspects of human and mouse bladder evolution were identified. We also discovered two novel types of human bladder cells. One type is ADRA2A ⁺ and HRH2 ⁺ interstitial cells which may be associated with nerve conduction and allergic reactions. The other type is TNNT1 ⁺ epithelial cells that may be involved with bladder emptying. We verify these TNNT1 ⁺ epithelial cells also occur in rat and mouse bladders.

CONCLUSIONS

This transcriptomic map provides a resource for studying bladder cell types, specific cell markers, signaling receptors, and genes that will help us to learn more about the relationship between bladder cell types and diseases.

Histological evidence supports low anesthetic bladder capacity as a marker of a bladder-centric disease subtype in interstitial cystitis/bladder pain syndrome

INTRODUCTION AND HYPOTHESIS

Low anesthetic bladder capacity has been shown to be a biomarker for bladder-centric interstitial cystitis/bladder pain syndrome (IC/BPS). The goal of this study was to determine if histopathological evidence from bladder biopsies supports anesthetic bladder capacity (BC) as a marker to distinguish a bladder-centric IC/BPS subtype.

METHODS

From a review of our large IC/BPS cohort of patients undergoing hydrodistention, we identified a total of 41 patients with low BC (≤ 400 ml); an additional 41 consecutive patients with BC > 400 ml were selected as the comparator group. The original bladder mucosal biopsy pathology slides were re-reviewed by a single pathologist (blinded to patient information) using a standardized grading scale developed for this study.

RESULTS

Histologically, the low BC subjects exhibited higher levels of acute inflammation (p = 0.0299), chronic inflammation (p = 0.0139), and erosion on microscopy (p = 0.0155); however, there was no significant difference in mast cell count between groups (p = 0.4431). There was no significant gender difference between the groups; female patients were the majority in both groups (low BC: 94.12%, non-low BC: 100%; p = 0.1246). Individuals in the low BC group were older (p < 0.0001), had a higher incidence of Hunner's lesions on cystoscopy (p < 0.0001), and had significantly higher scores, i.e., more bother symptoms, on two IC/BPS questionnaires (ICPI, p = 0.0154; ICSI, p = 0.0005).

CONCLUSIONS

IC/BPS patients with low anesthetic bladder capacity have histological evidence of significantly more acute and chronic inflammation compared with patients with a non-low bladder capacity. These data provide additional evidence to support low bladder capacity as a marker of a distinct bladder-centric IC/BPS phenotype.

The Vaginal and Urinary Microbiomes in Premenopausal Women With Interstitial Cystitis/Bladder Pain Syndrome as Compared to Unaffected Controls: A Pilot Cross-Sectional Study

Interstitial cystitis/bladder pain syndrome (ICBPS) may be related to an altered genitourinary microbiome. Our aim was to compare the vaginal and urinary microbiomes between premenopausal women with ICBPS and unaffected controls. This cross-sectional study screened premenopausal women with an O'Leary-Sant questionnaire (ICBPS if score ≥6 on either index; controls <6 on both). Women completed questionnaires on health characteristics, pelvic floor symptoms (OABq, PFDI-20), body image (mBIS), and sexual function (PISQ-IR). Bacterial genomic DNA was isolated from vaginal and clean-catch urinary specimens; the bacterial 16 rRNA gene was sequenced and analyzed using the QIIME pipeline. We performed UniFrac analysis (β-diversity) and generated Chao1 estimator (richness) and Simpson index (richness and evenness) values. We analyzed 23 ICBPS and 18 non-ICBPS patients. ICBPS patients had increased vaginal deliveries, BMI, and public insurance as well as worsened OAB-q, PFDI-20, mBIS, and PISQ-IR domain scores. Lactobacilli was the most abundant genus in both cohorts, and anaerobic or fastidious predominance was similar between groups (p = 0.99). For both the urine and vagina specimens, Chao1 and Simpson indices were similar between ICBPS and unaffected women. Weighted and unweighted UniFrac analyses showed no differences between groups. A significant correlation existed between the urinary and vaginal Simpson indices in ICBPS women, but not in unaffected women. Premenopausal women with ICBPS, despite worsened socioeconomic indicators and pelvic floor function, were not found to have significantly different urinary and vaginal microbiomes compared to women without ICBPS.

Histamine modulation of urinary bladder urothelium, lamina propria and detrusor contractile activity via H1 and H2 receptors

The mechanisms underlying bladder contractile disorders such as overactive bladder are not fully understood, and there is limited understanding of the receptor systems modulating spontaneous bladder contractions. We investigated the potential for histamine to have a role in mediating contractility of the urothelium with lamina propria (U&LP) or detrusor via the H1-H4 histamine receptor subtypes. Isolated strips of porcine U&LP or detrusor smooth muscle were mounted in gassed Krebs-bicarbonate solution and responses to histamine obtained in the absence and presence of selective receptor antagonists. The presence of histamine increases the frequency of U&LP spontaneous phasic contractions and baseline tensions. In response to histamine, H1-antagonists pyrilamine, fexofenadine and cyproheptadine were effective at inhibiting contractile responses. Cimetidine (H2-antagonist) enhanced increases in baseline tension in response histamine, whereas amthamine (H2-agonist) induced relaxation. Although thioperamide (H3/H4-antagonist) increased baseline tension responses to histamine, selective H1/H2-receptor antagonism revealed no influence of these receptors. In detrusor preparations, pyrilamine, fexofenadine and cyproheptadine were effective at inhibiting baseline tension increases in response to histamine. Our findings provide evidence that histamine produces contractile responses both in the U&LP and detrusor via the H1-receptor, and this response is significantly inhibited by activation of the H2-receptor in the U&LP but not the detrusor.

Therapeutic potential of intravesical injections of platelet-rich plasma in the treatment of lower urinary tract disorders due to regenerative deficiency

The bladder urothelium plays an important role of barrier function to prevent influx of urinary toxic substance and bacteria. When there is insult to the urinary bladder, the urothelium will start to regenerate on injury. However, several factors might affect the regenerative function of bladder urothelium, including aging, chronic inflammation, and system diseases such as diabetes and chronic kidney diseases (CKDs). Impairment of bladder mucosal regenerative function might result in defective urothelial cell differentiation as well as barrier function, which might be the underlying pathophysiology of interstitial cystitis/bladder pain syndrome (IC/BPS) and recurrent bacterial cystitis. Our previous immunohistochemistry (IHC) study and electron microscopic study revealed that the loss of normal umbrella cells and defective junction proteins in IC/BPS and recurrent cystitis. Platelet-rich plasma (PRP) has been previously used in many medical aspects as regenerative medicine therapy. PRP is rich in many growth factors and cytokines which modulate the process of inflammation and regeneration in the wound healing process. Recent pilot studies have shown that intravesical PRP injections improve IC symptoms and yield a success rate of 70% at 3 months after treatment. The results highly suggest that PRP injection could improve urothelial regenerative function and reduce chronic inflammation in IC patients. This article reviews recently published researches on the urothelial dysfunction biomarkers, urothelial cell differentiation, and urinary regenerative and inflammatory proteins in patients with IC/BPS or recurrent bacterial cystitis. The pathophysiology of the insufficient urothelial regeneration and differentiation; and chronic inflammation may induce urothelial dysfunction and further affect the regenerative ability of the diseased bladder urothelium in IC/BPS and recurrent bacterial cystitis are discussed.

Mechanisms Underlying Overactive Bladder and Interstitial Cystitis/Painful Bladder Syndrome

The bladder is innervated by extrinsic afferents that project into the dorsal horn of the spinal cord, providing sensory input to the micturition centers within the central nervous system. Under normal conditions, the continuous activation of these neurons during bladder distension goes mostly unnoticed. However, for patients with chronic urological disorders such as overactive bladder syndrome (OAB) and interstitial cystitis/painful bladder syndrome (IC/PBS), exaggerated bladder sensation and altered bladder function are common debilitating symptoms. Whilst considered to be separate pathological entities, there is now significant clinical and pre-clinical evidence that both OAB and IC/PBS are related to structural, synaptic, or intrinsic changes in the complex signaling pathways that mediate bladder sensation. This review discusses how urothelial dysfunction, bladder permeability, inflammation, and cross-organ sensitisation between visceral organs can regulate this neuroplasticity. Furthermore, we discuss how the emotional affective component of pain processing, involving dysregulation of the HPA axis and maladaptation to stress, anxiety and depression, can exacerbate aberrant bladder sensation and urological dysfunction. This review reveals the complex nature of urological disorders, highlighting numerous interconnected mechanisms in their pathogenesis. To find appropriate therapeutic treatments for these disorders, it is first essential to understand the mechanisms responsible, incorporating research from every level of the sensory pathway, from bladder to brain.