UPK3A+ umbrella cell damage mediated by TLR3-NR2F6 triggers programmed destruction of urothelium in Hunner-type interstitial cystitis/painful bladder syndrome.

Urothelial damage and barrier dysfunction emerge as the foremost mechanisms in Hunner-type interstitial cystitis/bladder pain syndrome (HIC). Although treatments aimed at urothelial regeneration and repair have been employed, their therapeutic effectiveness remains limited due to the inadequate understanding of specific cell types involved in damage and the lack of specific molecular targets within these mechanisms. Therefore, we harnessed single-cell RNA sequencing to elucidate the heterogeneity and developmental trajectory of urothelial cells within HIC bladders. Through reclustering, we identified eight distinct clusters of urothelial cells. There was a significant reduction in UPK3A+ umbrella cells and a simultaneous increase in progenitor-like pluripotent cells (PPCs) within the HIC bladder. Pseudotime analysis of the urothelial cells in the HIC bladder revealed that cells faced challenges in differentiating into UPK3A+ umbrella cells, while PPCs exhibited substantial proliferation to compensate for the loss of UPK3A+ umbrella cells. The urothelium in HIC remains unrepaired, despite the substantial proliferation of PPCs. Thus, we propose that inhibiting the pivotal signaling pathways responsible for the injury to UPK3A+ umbrella cells is paramount for restoring the urothelial barrier and alleviating lower urinary tract symptoms in HIC patients. Subsequently, we identified key molecular pathways (TLR3 and NR2F6) associated with the injury of UPK3A+ umbrella cells in HIC urothelium. Finally, we conducted in vitro and in vivo experiments to confirm the potential of the TLR3-NR2F6 axis as a promising therapeutic target for HIC. These findings hold the potential to inhibit urothelial injury, providing promising clues for early diagnosis and functional bladder self-repair strategies for HIC patients. © 2024 The Pathological Society of Great Britain and Ireland.

TRPV1 and mast cell involvement in repeated variate stress-induced urinary bladder dysfunction in adult female mice.

The etiology of interstitial cystitis/bladder pain syndrome (IC/BPS) is unknown but likely multifactorial. IC/BPS symptoms can be exacerbated by psychological stress, but underlying mechanisms remain to be defined. Transient receptor potential vanilloid 1 (TRPV1) channels, expressed on nerve fibers, have been implicated in bladder dysfunction and colonic hypersensitivity with stress in rodents. Histamine/H1R activation of TRPV1+ nerves increases bladder afferent fiber sensitivity to distension. TRPV1 channels are also expressed on mast cells, previously implicated in contributing to IC/BPS etiology and symptoms. We have examined the contribution of TRPV1 and mast cells to bladder dysfunction after repeated variate stress (RVS). RVS increased (P ≤ 0.05) serum and fecal corticosterone expression and induced anxiety-like behavior in wild-type (WT) mice. Intravesical instillation of the selective TRPV1 antagonist capsazepine (CPZ) rescued RVS-induced bladder dysfunction in WT mice. Trpv1 knockout (KO) mice did not increase voiding frequency with RVS and did not exhibit increased serum corticosterone expression despite exhibiting anxiety-like behavior. Mast cell-deficient mice (B6.Cg-Kitw-sh) failed to demonstrate RVS-induced increased voiding frequency or serum corticosterone expression, whereas control (no stress) mast cell-deficient mice had similar functional bladder capacity to WT mice. TRPV1 protein expression was significantly increased in the rostral lumbar (L1-L2) spinal cord and dorsal root ganglia (DRG) in WT mice exposed to RVS, but no changes were observed in lumbosacral (L6-S1) spinal segments or DRG. These studies demonstrated TRPV1 and mast cell involvement in RVS-induced increased voiding frequency and suggest that TRPV1 and mast cells may be useful targets to mitigate stress-induced urinary bladder dysfunction.NEW & NOTEWORTHY Using pharmacological tools and transgenic mice in a repeated variate stress (RVS) model in female mice, we demonstrate that transient receptor potential vanilloid 1 (TRPV1) and mast cells contribute to the increased voiding frequency observed following RVS. TRPV1 and mast cells should continue to be considered as targets to improve bladder function in stress-induced bladder dysfunction.

Cognitive Behavioral Therapy for Chronic Pelvic Pain: What Is It and Does It Work?

PURPOSE: Urologic chronic pelvic pain syndrome (UCPPS), which encompasses interstitial cystitis/bladder pain syndrome in women and men and chronic prostatitis/chronic pelvic pain syndrome in men, is a common, often disabling urological disorder that is neither well understood nor satisfactorily treated with medical treatments. The past 25 years have seen the development and validation of a number of behavioral pain treatments, of which cognitive behavioral therapy (CBT) is arguably the most effective. CBT combines strategies of behavior therapy, which teaches patients more effective ways of behaving, and cognitive therapy, which focuses on correcting faulty thinking patterns. As a skills-based treatment, CBT emphasizes "unlearning" maladaptive behaviors and thoughts, and replacing them with more adaptive ones that support symptom self-management. MATERIALS AND METHODS: This review describes the rationale, technical procedures, and empirical basis of CBT. RESULTS: While evidence supports CBT for treatment-refractory chronic pain disorders, there is limited understanding of why or how CBT might work, for whom it is most beneficial, or the specific UCPPS symptoms (eg, pain, urinary symptoms) it effectively targets. This is the focus of EPPIC (Easing Pelvic Pain Interventions Clinical Research Program), a landmark NIH trial examining the efficacy of low-intensity, home-based CBT for UCPPS relative to a nonspecific comparator featuring self-care recommendations of AUA guidelines. CONCLUSIONS: Systematic efforts to increase both the efficiency of CBT and the way it is delivered (eg, home-based treatments) are critical to scaling up CBT, optimizing its therapeutic potential, and reducing the public health burden of UCPPS.

Urologic Chronic Pelvic Pain Syndrome Flares: A Comprehensive, Systematic Review and Meta-Analysis of the Peer-Reviewed Flare Literature.

PURPOSE: We sought to systematically review and summarize the peer-reviewed literature on urologic chronic pelvic pain syndrome flares, including their terminology, manifestation, perceived triggers, management and prevention strategies, impact on quality of life, and insights into pathophysiologic mechanisms, as a foundation for future empirical research. MATERIALS AND METHODS: We searched 6 medical databases for articles related to any aspect of symptom exacerbations for interstitial cystitis/bladder pain syndrome and chronic prostatitis/chronic pelvic pain syndrome. A total of 1486 abstracts and 398 full-text articles were reviewed, and data were extracted by at least 2 individuals. RESULTS: Overall, we identified 59 articles, including 36 qualitative, cross-sectional, or case-control; 15 cohort-based; and 8 experimental articles. The majority of studies described North American patients with confirmed diagnoses. "Flare" was a commonly used term, but additional terminology (eg, exacerbation) was also used. Most flares involved significant increases in pain intensity, but less data were available on flare frequency and duration. Painful, frequent, long-lasting, and unpredictable flares were highly impactful, even over and above participants' nonflare symptoms. A large number of perceived triggers (eg, diet, stress) and management/prevention strategies (eg, analgesics, thermal therapy, rest) were proposed by participants, but few had empirical support. In addition, few studies explored underlying biologic mechanisms. CONCLUSIONS: Overall, we found that flares are painful and impactful, but otherwise poorly understood in terms of manifestation (frequency and duration), triggers, treatment, prevention, and pathophysiology. These summary findings provide a foundation for future flare-related research and highlight gaps that warrant additional empirical studies.

Elucidation of the pathophysiology of interstitial cystitis/bladder pain syndrome via experimental autoimmune cystitis rat model.

Although the cause of interstitial cystitis/painful bladder syndrome (IC/PBS) remains unknown, autoimmune involvement has been strongly suggested to be a contributing factor. To elucidate the pathophysiology of IC/PBS, we characterized the experimental autoimmune cystitis (EAC) in rats. Adult female Sprague-Dawley rats were divided into the EAC and control groups. The EAC rats were generated by administrating a homogenate of donor rat bladder tissue as a bladder antigen. The characteristics of the two groups were determined by evaluating pain behavior and conducting cystometry, histopathology, and molecular analyses. The EAC rats showed: 1) a decreased paw withdrawal threshold, 2) a reduced intercontraction interval on cystometry, 3) the irregular surfaces of the umbrella cells of epithelium throughout the bladder wall, 4) accumulation of stress granules in the bladder and vascular endothelium, 5)the increased expression of genes related to inflammation and ischemia at the mRNA and protein levels, 6) a significantly increased paw withdrawal threshold with pain treatment, and 7) the induction of glomerulation of the bladder wall, epithelium denudation, and lymphocyte infiltration in the interstitium by bladder distension. These results suggest that the EAC rats showed pain and frequent urination with the overexpression of inflammatory chemokines, reflecting clinical IC/BPS, and the bladder epithelium and vascular endothelium may be the primary sites of IC/BPS, and bladder injury, such as bladder distension, can cause progression from BPS to IC with Hunner lesions.NEW & NOTEWORTHY The experimental autoimmune cystitis model rats showed pain and frequent urination with the overexpression of inflammatory chemokines, reflecting clinical interstitial cystitis/painful bladder syndrome (IC/PBS), and the bladder epithelium and vascular endothelium may be the primary sites of IC/BPS, and bladder injury, such as bladder distension, can cause progression from BPS to IC with Hunner lesions.

Psychosexological correlates of 372 women with vulvodynia, overactive pelvic floor, postcoital cystitis, and interstitial cystitis.

BACKGROUND: Among the plethora of urogynecological conditions possibly affecting women, some of them, less explored, have significant impacts on sexological and psychological health, with a mutual influence. AIM: The aim of this study was to investigate the sexological and psychological correlates of four urogynecological pathologies in a sample of women of childbearing age: overactive pelvic floor, vulvodynia, postcoital cystitis, and interstitial cystitis. Women cured of these conditions were also included, to assess the same aspects after the remission of physical symptoms. METHODS: We recruited 372 women with an average age of 33.5 years through an online platform shared by a popular forum for women with urogynecological pathologies between March and May 2021. The participants filled out a socio-anamnestic questionnaire and a set of psychometric tests. OUTCOMES: Participant data were collected by use of the Patient Health Questionnaire-9, Generalized Anxiety Disorder-7, Toronto Alexithymia Scale-20, Female Sexual Function Index, and Orgasmometer-F, and the SPSS (Statistical Package for Social Sciences) v.26 was used for data analysis. RESULTS: Overactive pelvic floor was reported by 66.4% of the women, vulvodynia by 55%, postcoital cystitis by 58.8%, and interstitial cystitis by 8.3%, and these conditions were often comorbid with each other, with 9.4% and 7% of women reporting having suffered psychological and sexual abuse, respectively. The presence of past abuse was correlated with overactive pelvic floor (P < .05), vulvodynia (P < .01), and major depression (P < .01). Significantly more depression occurred in women with vulvodynia than in the other subgroups (P < .05), except for women with only an overactive pelvic floor. There was no difference between the subgroups in the occurrence of alexithymia, sexual function, and orgasm (P < .05). Interestingly, the prevalence of sexual dysfunction increased in cured women. CLINICAL IMPLICATIONS: The lack of significant differences, except for depression, between the pathological subgroups suggests a similar clinical and psychological relevance of the four pathologies studied. The persistence of sexual dysfunctions in cured women may be related to a residual dysfunctional relational modality with the partner. STRENGTHS AND LIMITATIONS: The evaluation of both psychological and sexological variables in a group of less-explored urogynecological conditions represents a strength of this study, while a lack of a face-to-face assessment could represent a limitation. CONCLUSION: The results of the present study should promote psychosexological interventions in women with these diseases, both during the pathological state and after remission.

Combination of urinary biomarkers and machine-learning models provided a higher predictive accuracy to predict long-term treatment outcomes of patients with interstitial cystitis/bladder pain syndrome.

PURPOSE: To identify predictive factors for satisfactory treatment outcome of the patients with IC/BPS using urine biomarkers and machine-learning models. METHODS: The IC/BPS patients were prospectively enrolled and provide urine samples. The targeted analytes included inflammatory cytokines, neurotrophins, and oxidative stress biomarkers. The patients with overall subjective symptom improvement of ≥ 50% were considered to have satisfactory results. Binary logistic regression, receiver-operating characteristic (ROC) curve, machine-learning decision tree, and random forest models were used to analyze urinary biomarkers to predict satisfactory results. RESULTS: Altogether, 57.4% of the 291 IC/BPS patients obtained satisfactory results. The patients with satisfactory results had lower levels of baseline urinary inflammatory cytokines and oxidative biomarkers than patients without satisfying results, including interleukin-6, monocyte chemoattractant protein-1 (MCP-1), C-X-C motif chemokine 10 (CXCL10), oxidative stress biomarkers 8-hydroxy-2'-deoxyguanosine (8-OHDG), 8-isoprostane, and total antioxidant capacity (TAC). Logistic regression and multivariable analysis revealed that lower levels of urinary CXCL10, MCP-1, 8-OHDG, and 8-isoprostane were independent factors. The ROC curve revealed that MCP-1 level had best area under curve (AUC: 0.797). In machine-learning decision tree model, combination of urinary C-C motif chemokine 5, 8-isoprostane, TAC, MCP-1, and 8-OHDG could predict satisfactory results (accuracy: 0.81). The random forest model revealed that urinary 8-isoprostance, MCP-1, and 8-OHDG levels had the most important influence on accuracy. CONCLUSION: Machine learning decision tree model provided a higher accuracy for predicting treatment outcome of patients with IC/BPS than logistic regression, and levels of 8-isoprostance, MCP-1, and 8-OHDG had the most important influence on accuracy.

Latest insights into the pathophysiology of bladder pain syndrome/interstitial cystitis.

PURPOSE OF REVIEW: Bladder pain syndrome/interstitial cystitis (BPS/IC) is a common medical problem in both sexes affecting people of all ages. Patients might report overactive bladder symptoms with additional bladder pain at maximum bladder filling, during and after micturition. This review aims to highlight pathophysiological mechanisms associated with this disease. RECENT FINDINGS: Latest literature exposes different pathophysiological mechanisms such as impaired urothelial barrier function, alteration of urothelial factors and cytokines, chronic inflammation, vascular lesions, neurogenic inflammation and processes in the central nervous system leading to central sensitization. According to the involved mechanisms, BPS/IC may be arranged in clusters according to the clinical phenotype thus helping in clinical decision-making and treatment. Moreover, patients with BPS/IC suffer from other comorbidities such as fibromyalgia, irritable bowel syndrome, chronic pain and functional syndromes and psychosomatic diseases making the management challenging for medical professionals. SUMMARY: Bladder pain syndrome/interstitial cystitis is a complex heterogeneous medical condition involving different pathomechanisms leading to bladder pain and dysfunction, consequently, impairing quality-of-life in affected individuals. However, these mechanisms are still not fully understood, so that patient treatments often remain unsatisfactory. For this reason, continuing research is important to understand the underlying pathomechanisms to discover biomarkers and treatment targets eventually improving diagnostic and therapeutic measures of BPS/IC.

What is in the pipeline for new treatments for bladder pain syndrome/ interstitial cystitis?

PURPOSE OF REVIEW: Despite available treatments, many bladder pain syndrome/interstitial cystitis (BPS/IC) patients continue to have poor quality of life. Thus, there is an urge for new therapies. Our manuscript aims to review papers about BPS/IC treatments published in the last 2 years. RECENT FINDINGS: During this period, several treatments were tested, most of them new and others combining treatments already used. Pentosan polysulfate, interleukin 1 antagonist, low energy shock wave, physical therapy, hypnosis, acupuncture, clorpactin, dimethyl sulfoxide and hyaluronic acid plus botulinum toxin-A showed positive results. ASP3652 and lidocaine-releasing intravesical systems failed to prove their efficacy. SUMMARY: Validation of these studies is arduous due to the broad spectre of BPS/IC phenotypes, small number of patients enrolled, distinct outcome measures and short-term follow-up. It is also important to highlight that some authors combined therapies, and others split central and peripheric phenotypes before treatment. Therefore, soon, phenotyping and combining therapies with a step-by-step approach will be needed in BPS/IC treatment.

Multi-omics analyses uncover metabolic signatures and gene expression profiles of interstitial cystitis/bladder pain syndrome.

BACKGROUND AND OBJECTIVE: We explore molecular and metabolic pathways involved in interstitial cystitis (IC) with integrating multi-omics analysis for identifying potential diagnostic and therapeutic targets. METHODS: Mouse models of IC/bladder pain syndrome (BPS) were established by intraperitoneal injection of cyclophosphamide and bladder tissue samples were collected for metabolomics and transcriptome analysis. RESULTS: We found a total of 82 and 145 differential metabolites in positive ion modes and negative ion modes, respectively. Glycerophospholipid metabolism, choline metabolism in cancer, and nucleotide metabolism pathways were significantly enriched in the IC/BPS group. Transcriptome analysis demonstrated that 1069 upregulated genes and 1087 downregulated genes were detected. Importantly, the stronger enrichment for cell cycle pathway was observed in IC/BPS than that in normal bladder tissue, which may be involved in the process of bladder remodeling. Moreover, the inflammatory response and inflammatory factors related pathways were enriched in the IC/BPS group. CONCLUSIONS: Our findings provide critical directions for further exploration of the molecular pathology underlying IC/BPS.

The effects of a galectin-3 inhibitor on bladder pain syndrome in mice with cyclophosphamide-induced cystitis.

AIMS: To explore the effect of blocking galectin-3 in the bladder pain syndrome associated with interstitial cystitis. METHODS: A galectin-3 inhibitor was used to treat mice with cyclophosphamide-induced cystitis. The expression of galectin-3 in bladder tissues and urine was examined by immunohistochemistry and enzyme-linked immunosorbent assay (ELISA), respectively. Suprapubic-pelvic pain, bladder voiding, bladder pain-like nociceptive behavior, and referred hyperalgesia were assessed. The weights of the bladders were also measured, and inflammatory cell infiltration and inflammatory cytokine levels were examined by histopathological evaluation. The inflammatory cytokines interleukin 1ß (IL-1ß), nerve growth factor (NGF), IL-6, and tumor necrosis factor α (TNF-α) were measured by ELISA. RESULTS: Increases in galectin-3 levels, inflammation, bladder weight, and bladder pain-related symptoms were observed in bladders with cyclophosphamide-induced cystitis. Administration of the galectin-3 inhibitor significantly mitigated bladder pain-related symptoms and inflammatory response. In response to the 500 µM dose of the galectin-3 inhibitor, nociceptive behaviors, nociceptive score, and bladder-to-body weight ratios were reduced by 65.1%, 65.3%, and 40.3%, respectively, while 500 µM Gal-3 inhibitor increased pelvic pain threshold by 86.7%. Moreover, galectin-3 inhibitor treatment inhibited the inflammation. Compared to untreated CYP-induced mice, there were significant changes in the levels of IL-1ß (41.72 ± 2.05 vs. 18.91 ± 2.26 pg/mg tissues), NGF (9.64 ± 0.38 vs. 1.88 ± 0.05 pg/mg tissues), IL-6 (42.67 + 1.51 vs. 21.26 + 2.78 pg/mg tissues, and TNF-α (22.02 ± 1.08 vs. 10.70 ± 0.80 pg/mg tissues) in response to the highest dose of the Gal-3 inhibitor subgroup (500 µM), and 500 µM Gal-3 inhibitor reduced mast cell infiltration ratios by 71.8%. CONCLUSIONS: The galectin-3 inhibitor relieved pelvic pain, urinary symptoms, and bladder inflammation in mice with cyclophosphamide-induced cystitis. Thus, galectin-3 inhibitors may be novel agents in interstitial cystitis treatment.

Early in life stressful events induce chronic visceral pain and changes in bladder function in adult female mice through a mechanism involving TRPV1 and alpha 1A adrenoceptors.

BACKGROUND: Interstitial cystitis/bladder pain syndrome (IC/BPS) is a chronic pain disorder with multiple phenotypes, one of which is associated with an overactive adrenergic system. OBJECTIVE: We investigated if the maternal deprivation model (MDM) in female and male mice mimics IC/BPS phenotype and if the overstimulation of alpha 1A adrenoceptor (A1AAR) and the crosstalk with transient receptor potential vanilloid-1 (TRPV1) are involved in the generation of pain and bladder functional changes. DESIGN, SETTING, AND PARTICIPANTS: C57BL/6 female and male mice were submitted to MDM. TRPV1 knockout (KO) mice were used to study TRPV1 involvement. Silodosin administration to MDM mice was used to study A1AAR involvement. OUTCOME MEASUREMENTS AND STATISTICAL ANALYSIS: The primary outcome was chronic visceral pain measured by Von Frey filaments analysis (effect size: 3 for wild type, 3.9 for TRPV1 KO). Bladder changes were secondary outcome measurements. Unpaired T test, Mann-Whitney test, one-way analysis of variance followed by Newman-Keuls multiple comparisons test, and Kruskal-Wallis followed by Dunn's multiple comparisons test were used where appropriate. RESULTS AND LIMITATIONS: MDM induces pain behavior in female and not in male mice. Bladder afferents seem sensitize as MDM also increase the number of small volume spots voided, the bladder reflex activity, and urothelial damage. These changes were similarly absent after A1AAR blockade with silodosin or by TRPV1 gene KO. The main limitation is the number/type of pain tests used. CONCLUSIONS: MDM induced in female mice is able to mimic IC/BPS phenotype, through mechanisms involving A1AAR and TRPV1. Therefore, the modulation of both receptors may represent a therapeutic approach to treat IC/BPS patients.

Validation of a simple body map to measure widespread pain in urologic chronic pelvic pain syndrome: A MAPP Research Network study.

PURPOSE: In patients with urologic chronic pelvic pain syndrome (UCPPS), the presence of widespread pain appears to identify a distinct phenotype, with a different symptom trajectory and potentially different response to treatment than patients with pelvic pain only. MATERIALS AND METHODS: A 76-site body map was administered four times, at weekly intervals, to 568 male and female UCPPS participants in the MAPP Network protocol. The 76 sites were classified into 13 regions (1 pelvic region and 12 nonpelvic regions). The degree of widespread pain was scored from 0 to 12 based on the number of reported nonpelvic pain regions. This continuous body map score was regressed over other measures of widespread pain, with UCPPS symptom severity, and with psychosocial variables to measure level of association. These models were repeated using an updated body map score (0-12) that incorporated a threshold of pain ≥ 4 at each site. RESULTS: Body map scores showed limited variability over the 4 weekly assessments, indicating that a single baseline assessment was sufficient. The widespread pain score correlated highly with other measures of widespread pain and correlated with worsened UCPPS symptom severity and psychosocial functioning. Incorporating a pain severity threshold ≥4 resulted in only marginal increases in these correlations. CONCLUSIONS: These results support the use of this 13-region body map in the baseline clinical assessment of UCPPS patients. It provides reliable data about the presence of widespread pain and does not require measurement of pain severity, making it relatively simple to use for clinical purposes.

Evaluation of Central Sensitisation in Bladder Pain Syndrome: A Systematic Review.

INTRODUCTION AND HYPOTHESIS: Bladder pain syndrome (BPS) is a debilitating condition characterised by exaggerated bladder sensations and altered bladder function. It is still unknown whether the condition is a peripheral sensory problem or due to abnormal central sensory processing as seen in central sensitisation. This systematic review, which followed a published and Prospective Register of Systematic Reviews-registered protocol (CRD42021229962), is aimed at establishing the scope of central sensitisation in patients with BPS to aid optimal management and treatment. METHODS: Four databases were searched, and appraisal of the identified studies was conducted by two independent reviewers based on eligibility criteria: patients with BPS being investigated for central sensitisation with or without comparison of controls, English-language articles, full text and publication in a peer-reviewed journal. The Methodological Index for non-Randomised Studies was used to determine study quality. We identified 763 papers in total, with 15 studies included in the final analysis. All studies were observational and had a low risk of bias. Measures included in the evaluation of CS were questionnaires, urodynamics, and quantitative sensory testing methods. RESULTS: There was evidence of central sensitisation in patients with BPS in all papers evaluated (15 out of 15). In addition, more significant central sensitisation correlated with severe disease presentation (3 out of 3 papers) and concomitant chronic pain conditions (5 out of 5 papers). CONCLUSIONS: Central sensitisation plays an integral role in BPS patient pathology. Many secondary measures are used to evaluate this condition. Stratification of patients based on their pathology (peripheral, central or a combination of the two) will aid in implementing an individualised management strategy.

Validation of Distinct Bladder Pain Phenotypes Utilizing the MAPP Research Network Cohort.

INTRODUCTION AND HYPOTHESIS: As interstitial cystitis/bladder pain syndrome (IC/BPS) likely represents multiple pathophysiologies, we sought to validate three clinical phenotypes of IC/BPS patients in a large, multi-center cohort using unsupervised machine learning (ML) analysis. METHODS: Using the female Genitourinary Pain Index and O'Leary-Sant Indices, k-means unsupervised clustering was utilized to define symptomatic phenotypes in 130 premenopausal IC/BPS participants recruited through the Multidisciplinary Approach to the Study of Chronic Pelvic Pain (MAPP) research network. Patient-reported symptoms were directly compared between MAPP ML-derived phenotypic clusters to previously defined phenotypes from a single center (SC) cohort. RESULTS: Unsupervised ML categorized IC/BPS participants into three phenotypes with distinct pain and urinary symptom patterns: myofascial pain, non-urologic pelvic pain, and bladder-specific pain. Defining characteristics included presence of myofascial pain or trigger points on examination for myofascial pain patients (p = 0.003) and bladder pain/burning for bladder-specific pain patients (p < 0.001). The three phenotypes were derived using only 11 features (fGUPI subscales and ICSI/ICPI items), in contrast to 49 items required previously. Despite substantial reduction in classification features, unsupervised ML independently generated similar symptomatic clusters in the MAPP cohort with equivalent symptomatic patterns and physical examination findings as the SC cohort. CONCLUSIONS: The reproducible identification of IC/BPS phenotypes, distinguishing bladder-specific pain from myofascial and genital pain, using independent ML analysis of a multicenter database suggests these phenotypes reflect true pathophysiologic differences in IC/BPS patients.

Therapeutic Effects of AF219 on Interstitial Cystitis/Bladder Pain Syndrome Induced by Cyclophosphamide or Water Avoidance Stress in Rats.

INTRODUCTION AND HYPOTHESIS: To evaluate the effect of AF219, a P2X3 receptor antagonist, in animal models of interstitial cystitis/bladder pain syndrome (IC/BPS) induced by cyclophosphamide (CYP) or water avoidance stress (WAS). METHODS: Thirty-two adult female Wistar albino rats were used in each IC/BPS model. Assessment of nociception and anxiety and severity of inflammation in the bladder were assessed by behavioral experiments and histopathological examinations respectively. The contraction responses of the bladder were evaluated in vitro and protein levels of P2X3, P2X7, Trk-A, TRPV1, and TRPA1 were analyzed by Western blot. RESULTS: The IC/BPS groups had shorter response times to noxious stimuli, exhibited more anxiety-like behavior, had higher inflammation-based histological scores, and showed greater increased contraction responses to carbachol, adenosine triphosphate, and electrical field stimulation in in vitro bladder strips than controls for both models (p < 0.05). The improvements in behavioral and bladder contraction responses and inflammation scores in the IC/BPS + AF219 groups were similar to control findings (p > 0.05). Exposure to WAS or CYP increased P2X3 expression in the bladder compared with the controls (p < 0.05). Apart from TRPA1, the levels of P2X7, Trk-A, and TRPV1 were also higher in the IC/BPS groups than in the controls (p < 0.05). No significant differences were observed between IC/BPS + AF219 and controls regarding P2X3, P2X7, Trk-A, and TRPV1 in the WAS model (p > 0.05). Moreover, P2X3 and P2X7 levels were significantly lower in IC/BPS + AF219 than in the AF219-untreated WAS model (p < 0.05). CONCLUSIONS: These findings suggest that P2X3 receptors play a significant role in bladder functional responses, nociception, and also the pathogenesis of IC/BPS. AF219 may be a promising therapeutic strategy for IC/BPS. Comparing AF219 with current IC/BPS treatment agents in future studies may yield valuable insights into its efficacy.

Cytokines in Bladder Pain Syndrome: A Review of the Literature.

INTRODUCTION AND HYPOTHESIS: Bladder pain syndrome (BPS) is poorly understood with both the aetiology and pathophysiology being unknown. Symptoms overlap with other disorders, such as overactive bladder (OAB) and chronic pelvic pain disorders such as endometriosis, making a consensus on how to diagnosis and manage patients challenging. The development of biomarkers for BPS may be the key to understanding more about its pathophysiology, as well as aiding diagnosis, subclassification, and discovering new drug targets for its management. As inflammation is widely understood to hold a central role in BPS, the evaluation of cytokines has gained interest. This article summarises the current literature and understanding of urinary, serum, and bladder tissue cytokines found elevated in patients with bladder pain syndrome. METHODS: literature search using Pub Med with the keywords "bladder pain syndrome", "painful bladder syndrome", "bladder pain", "Interstitial cystitis" AND "cytokines" or "inflammation". This study was except from institutional approval. RESULTS: Thirty-six cytokines have been identified as being statistically significantly elevated in either the serum, urine, or bladder tissue of patients with bladder pain syndrome in the 22 studies identified in this review of the literature. These cytokines include those from the interleukin group (n = 14), the CXC chemokine group (n = 5), and the C-C chemokine group (n = 7). CONCLUSIONS: CXCL-1, CXCL-8, CXCL-9, CXCL-10, CXCL-11 from the CXC chemokine group, and CCL2, CCL4, CCL5, CCL7, and CCL11 from the C-C chemokine group have been found to be significantly elevated in patients with bladder pain in the literature. Many of these analytes also have supporting evidence for their roles in bladder pain from animal models and studies in other chronic inflammatory conditions. It is likely that a single cytokine will not serve as an adequate biomarker of disease in bladder pain syndrome for either diagnosis or disease severity. Instead, panels of inflammatory mediators may reveal more about the different pathways of inflammation leading to similar presentations of bladder pain in patients.

Current updates relating to treatment for interstitial cystitis/bladder pain syndrome: systematic review and network meta-analysis.

BACKGROUND: Despite the publication of several meta-analyses regarding the efficacy of certain therapies in helping individuals with interstitial cystitis (IC) / bladder pain syndrome (BPS), these have not provided a comprehensive review of therapeutic strategies. The study aimed to determine the efficacy of various therapies for IC/BPS and identify potential moderating factors using randomized controlled trials (RCTs). METHODS: We queried the PubMed, Cochrane, and Embase databases to identify prospective RCTs using inclusion criteria: 1) patients diagnosed with IC, 2) interventions included relevant treatments, 3) comparisons were a specified control or placebo, 4) outcomes were mean differences for individual symptoms and structured questionnaires. The pairwise meta-analysis and network meta-analysis (NMA) were performed to compare the treatments used in IC/BPS. Hedges' g standardized mean differences (SMDs) were used for improvement in all outcomes using random-effects models. Efficacy outcomes included individual symptoms such as pain, frequency, urgency, and nocturia, as well as structured questionnaires measuring IC/BPS symptoms. RESULTS: A comprehensive literature search was conducted which identified 70 RCTs with 3,651 patients. The analysis revealed that certain treatments, such as instillation and intravesical injection, showed statistically significant improvements in pain and urgency compared to control or placebo groups in traditional pairwise meta-analysis. However, no specific treatment demonstrated significant improvement in all outcomes measured in the NMA. The results of moderator analyses to explore influential variables indicated that increasing age was associated with increased nocturia, while longer follow-up periods were associated with decreased frequency. CONCLUSION: This systematic review and meta-analysis provide insights into the efficacy of various treatments for IC. Current research suggests that a combination of therapies may have a positive clinical outcome for patients with IC, despite the fact that treatment for this condition is not straightforward. TRIAL REGISTRATION: PROSPERO CRD42022384024.

Hypertension and urologic chronic pelvic pain syndrome: An analysis of MAPP-I data.

BACKGROUND: Urologic chronic pelvic pain syndrome (UCPPS), which includes interstitial cystitis/bladder pain syndrome (IC/BPS) and chronic prostatitis (CP/CPPS), is associated with increased voiding frequency, nocturia, and chronic pelvic pain. The cause of these diseases is unknown and likely involves many different mechanisms. Dysregulated renin-angiotensin-aldosterone-system (RAAS) signaling is a potential pathologic mechanism for IC/BPS and CP/CPPS. Many angiotensin receptor downstream signaling factors, including oxidative stress, fibrosis, mast cell recruitment, and increased inflammatory mediators, are present in the bladders of IC/BPS patients and prostates of CP/CPPS patients. Therefore, we aimed to test the hypothesis that UCPPS patients have dysregulated angiotensin signaling, resulting in increased hypertension compared to controls. Secondly, we evaluated symptom severity in patients with and without hypertension and antihypertensive medication use. METHODS: Data from UCPPS patients (n = 424), fibromyalgia or irritable bowel syndrome (positive controls, n = 200), and healthy controls (n = 415) were obtained from the NIDDK Multidisciplinary Approach to the Study of Chronic Pelvic Pain I (MAPP-I). Diagnosis of hypertension, current antihypertensive medications, pain severity, and urinary symptom severity were analyzed using chi-square test and t-test. RESULTS: The combination of diagnosis and antihypertensive medications use was highest in the UCPPS group (n = 74, 18%), followed by positive (n = 34, 17%) and healthy controls (n = 48, 12%, p = 0.04). There were no differences in symptom severity based on hypertension in UCPPS and CP/CPPS; however, IC/BPS had worse ICSI (p = 0.031), AUA-SI (p = 0.04), and BPI pain severity (0.02). Patients (n = 7) with a hypertension diagnosis not on antihypertensive medications reported the greatest severity of pain and urinary symptoms. CONCLUSION: This pattern of findings suggests that there may be a relationship between hypertension and UCPPS. Treating hypertension among these patients may result in reduced pain and symptom severity. Further investigation on the relationship between hypertension, antihypertensive medication use, and UCPPS and the role of angiotensin signaling in UCPPS conditions is needed.

Obstructive sleep apnea and bladder pain syndrome/interstitial cystitis in women.

PURPOSE: The relationship between obstructive sleep apnea (OSA) and bladder pain syndrome/interstitial cystitis (BPS/IC) remains uncertain. Therefore, this study aimed to compare the frequency of BPS/IC seen in women diagnosed with OSA and in women without OSA. MATERIAL AND METHODS: The study included a patient group of women with OSA and a control group of women without OSA. All the study participants were administered the Berlin Questionnaire, Epworth Sleepiness Scale, Interstitial Cystitis Symptom Index (ICSI), and the Interstitial Cystitis Problem Index (ICPI). Differences between the women with OSA and the control group were examined. RESULTS: The study sample consisted of 46 women with OSA and 46 controls. No significant difference was determined between the OSA and control groups concerning age and body mass index (p = 0.810, p = 0.060, respectively). The ESS was greater in the OSA group than in the control group (p = 0.007). The median (IQR) ICSI was 8 (4-11.25) in women with OSA and 5 (1.75-7.15) in controls (p < 0.001). The median (IQR) ICPI was 7 (6.00-10.25) in women with OSA and 6 (1.75-8.00) in controls (p < 0.001).  CONCLUSIONS: The ICSI symptoms and subsequent problems in daily life caused by the symptoms (ICPI) were experienced at a higher rate in patients with OSA than in the control group. There is an association between BPS/IC and OSA.