CXCR3 Binding Chemokine and TNFSF14 Over Expression in Bladder Urothelium of Patients With Ulcerative Interstitial Cystitis

Emodin suppresses mast cell migration via modulating the JAK2/STAT3/JMJD3/CXCR3 signaling to prevent cystitis

AIMS

This study aimed to determine the preventive effects of emodin on cyclophosphamide (CYP)-induced cystitis and to explore the molecular mechanism.

METHODS

In vivo, mice were modeled by CYP. Before a half hour of CYP treatment, Jumonji domain-containing protein-3 (JMJD3) inhibitors (GSK-J4) and emodin were used to treat CYP model mice. Bladder samples were stained for hematoxylin-eosin and toluidine blue. Next, JMJD3 was quantified by immunofluorescence staining, RT-PCR, and Western blot. CXCR3 was quantified by Western blot and ELISA. In vitro, before stimulated by lipopolysaccharide (LPS), human bladder smooth muscle cells (hBSMCs) were transfected with pcDNA3.1-JMJD3 plasmids, shRNA-JMJD3 plasmids or pretreated with emodin. Collected cells to detect JMJD3 and CXCR3 ligands again; collected supernatant of culture for Transwell assay. Finally, as the JAK2 inhibitor, AG490 was used to pretreat LPS-induced hBSMCs. Western blot was performed to quantify proteins.

RESULTS

Emodin inhibited mast cell migration and suppressed the expression of JMJD3, CXCR3, and CXCR3 ligands, not only in vivo but also in vitro. The pharmacological effects of emodin were similar to GSK-J4 or JMJD3 inhibition. In addition, emodin significantly downregulated the phosphorylation of JAK2 and STAT3, and inhibited JMJD3/CXCR3 axis transduction like AG490.

CONCLUSION

Emodin has a preventive effect on cystitis by inhibiting mast cell migration through inhibition of the JAK2/STAT3/JMJD3/CXCR3 signaling pathway.

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.

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.

Th1/17 polarization and potential treatment by an anti-interferon-γ DNA aptamer in Hunner-type interstitial cystitis

Hunner-type interstitial cystitis (HIC) is a rare, enigmatic inflammatory disease of the urinary bladder with no curative treatments. In this study, we aimed to characterize the unique cellular and immunological factors specifically involved in HIC by comparing with cystitis induced by Mycobacterium bovis bacillus Calmette-Guérin, which presents similar clinicopathological features to HIC. Here, we show that T helper 1/17 +polarized immune responses accompanied by prominent overexpression of interferon (IFN)-γ, enhanced cGAS-STING cytosolic DNA sensing pathway, and increased plasma cell infiltration are the characteristic inflammatory features in HIC bladder. Further, we developed a mouse anti-IFN-γ DNA aptamer and observed that the intravesical instillation of the aptamer significantly ameliorated bladder inflammation, pelvic pain and voiding dysfunction in a recently developed murine HIC model with little migration into the blood. Our study provides the plausible basis for the clinical translation of the anti-IFN-γ DNA aptamer in the treatment of human HIC.

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.

TRPV4 activation prevents lipopolysaccharide-induced painful bladder hypersensitivity in rats by regulating immune pathways

Chronic inflammation in the urinary bladder is a potential risk factor for bladder dysfunction, including interstitial cystitis/bladder pain syndrome (IC/BPS). Although several studies have reported that activation of transient receptor potential vanilloid 4 (TRPV4) contributes to bladder pain and overactive bladder with a cardinal symptom of acute or chronic cystitis, others have reported its involvement in the protective response mediated by lipopolysaccharides (LPS) to secrete anti-inflammatory/pro-resolution cytokines. Therefore, we investigated the potential benefit of an intravesical TRPV4 agonist for painful bladder hypersensitivity in a rat model of LPS-induced cystitis and determined whether its effects modulate the LPS signal for inflammatory reaction, cytokine release, and macrophage phenotype change. Previously, we showed that repeated intravesical instillations of LPS induce long-lasting bladder inflammation, pain, and overactivity in rats. In the present study, concurrent instillation of the selective TRPV4 agonist GSK1016790A (GSK) with LPS into the rat bladder improved LPS-induced bladder inflammation and reduced the number of mast cells. Furthermore, co-instillation of GSK prevented an increase in bladder pain-related behavior and voiding frequency caused by LPS. Cytokine profiling showed that LPS-stimulated inflammatory events, such as the production and secretion of pro-inflammatory cytokines (CXCL1, CXCL5, CXCL9, CXCL10, CCL3, CCL5, CCL20, and CX3CL1), are suppressed by GSK. Furthermore, TRPV4 activation switched LPS-stimulated pro-inflammatory M1-type macrophages to anti-inflammatory M2-type macrophages. These results suggest that TRPV4 activation in the bladder negatively regulates the pro-inflammatory response induced by LPS and prevents bladder hypersensitivity. These TRPV4 functions may be promising therapeutic targets for refractory IC/BPS.

Cystitis Induces Altered CREB Expression Related with Micturition Reflex

Background and objectives: Bladder stimulation upregulates neurotrophins associated with voiding reflex. Bacterial cystitis can be a stimulant that activates this system, resulting in a pathological state. Phosphorylated responsive element of binding protein (p-CREB) is a pivotal transcriptional factor in the neurotrophin signaling cascade. The goal of our study was to examine the change in expression of p-CREB in dorsal root ganglia (DRG) of rats after uropathogenic Escherichia coli infection of the bladder. Materials and methods: A total of 19 adult female Sprague−Dawley rats were induced with acute E. coli infection (n = 7), chronic E. coli infection (n = 6), or served as controls (n = 6). In each group, the profiles of p-CREB cell were counted in 6−10 sections of each of the DRG collected. DRG cells exhibiting intense nuclear staining were considered to be positive for p-CREB immunoreactivity (p-CREB-IR). Results: Overall, the immunoreactivity of p-CREB was examined in smaller cell profiles with nuclear staining or nuclear and cytoplasmic staining in the DRGs (L1−L6, S1). In the chronic cystitis group, p-CREB-IR in the L1−L6 and S1 DRG was significantly higher than the control group (p < 0.05). Further, p-CREB-IR in the L3−L6 and S1 DRG of the chronic cystitis group was significantly greater than that in the acute cystitis group (p < 0.05). In the control and acute cystitis groups, p-CREB-IR in the L4−L5 DRG was significantly lower than that found in the other DRG sections (p < 0.05). Conclusions: Altogether, acute or chronic E.coli cystitis changed the immunoreactivity of p-CREB in lumbosacral DRG cells. In particular, chronic E. coli infection triggered p-CREB overexpression in L1−L6 and S1 DRG, indicating subsequent pathologic changes.

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.

Gene Expression-Based Functional Differences between the Bladder Body and Trigonal Urothelium in Adolescent Female Patients with Micturition Dysfunction

The aim of this study is to determine the molecular differences between the urothelial transcriptomes of the bladder body and trigone. The transcriptomes of the bladder body and trigonal epithelia were analyzed by massive sequencing of total epithelial RNA. The profiles of urothelial and urinal microbiomes were assessed by amplicon sequencing of bacterial 16S rRNA genes in 17 adolescent females with pain and micturition dysfunction and control female subjects. The RNA sequencing identified 10,261 differentially expressed genes (DEGs) in the urothelia of the bladder body and trigone, with the top 1000 DEGs at these locations annotated to 36 and 77 of the Reactome-related pathways in the bladder body and trigone, respectively. These pathways represented 11 categories enriched in the bladder body urothelium, including extracellular matrix organization, the neuronal system, and 15 categories enriched in the trigonal epithelium, including RHO GTPase effectors, cornified envelope formation, and neutrophil degranulation. Five bacterial taxa in urine differed significantly in patients and healthy adolescent controls. The evaluation of their transcriptomes indicated that the bladder body and trigonal urothelia were functionally different tissues. The molecular differences between the body and trigonal urothelia responsible for clinical symptoms in adolescents with bladder pain syndrome/interstitial cystitis remain unclear.

Therapeutic potential of nanoceria pretreatment in preventing the development of urological chronic pelvic pain syndrome: Immunomodulation via reactive oxygen species scavenging and SerpinB2 downregulation

Urological chronic pelvic pain syndrome (UCPPS) manifests as pelvic pain with frequent urination and has a 10% prevalence rate without effective therapy. Nanoceria (cerium oxide nanoparticles [CNPs]) were synthesized in this study to achieve potential long-term pain relief, using a commonly used UCPPS mouse model with cyclophosphamide-induced cystitis. Transcriptome sequencing analysis revealed that serpin family B member 2 (SerpinB2) was the most upregulated marker in mouse bladder, and SerpinB2 was downregulated with CNP pretreatment. The transcriptome sequencing analysis results agreed with quantitative polymerase chain reaction and western blot analysis results for the expression of related mRNAs and proteins. Analysis of Gene Expression Omnibus (GEO) datasets revealed that SerpinB2 was a differentially upregulated gene in human UCPPS. In vitro SerpinB2 knockdown downregulated proinflammatory chemokine expression (chemokine receptor CXCR3 and C-X-C motif chemokine ligand 10) upon treatment with 4-hydroperoxycyclophosphamide. In conclusion, CNP pretreatment may prevent the development of UCPPS, and reactive oxygen species (ROS) scavenging and SerpinB2 downregulation may modulate the immune response in UCPPS.

Inflammation-Independent Antinociceptive Effects of DF2755A, a CXCR1/2 Selective Inhibitor: A New Potential Therapeutic Treatment for Peripheral Neuropathy Associated to Non-Ulcerative Interstitial Cystitis/Bladder Pain Syndrome

Interstitial cystitis (IC)/bladder pain syndrome (BPS) is a chronic bladder disease of unknown etiology characterized by urinary frequency and episodic and chronic pain. Analgesic treatments for IC/BPS are limited, especially for patients with non-Hunner (non-ulcerative) type IC who usually have poor overall outcomes. Here, we demonstrate that oral treatment with DF2755A, a potent and selective inhibitor of chemokine receptors CXCR1/2, can prevent and reverse peripheral neuropathy associated to non-Hunner IC/BPS by directly inhibiting chemokine-induced excitation of sensory neurons. We tested DF2755A antinociceptive effects in a cyclophosphamide (CYP)-induced non-ulcerative IC rat model characterized by severe peripheral neuropathy in the absence of bladder inflammatory infiltrate, urothelial hyperplasia, and hemorrhage. Treatment with DF2755A prevented the onset of peripheral neuropathy and reversed its development in CYP-induced IC rats, showing a strong and long-lasting anti-hyperalgesic effect. Ex vivo and in vitro studies showed that DF2755A treatment strongly inhibited the expression of CXCR2 agonists, CXCL1/KC, and CXCL5 and of transient receptor potential vanilloid 1 (TRPV1) compared to vehicle, suggesting that its effects can be due to the inhibition of the nociceptive signaling passing through the CXCL1/CXCR1-2 axis and TRPV1. In conclusion, our results highlight the key pathophysiological role played by the CXCL1/CXCR1-2 axis and TRPV1 in the onset and development of peripheral neuropathy in non-Hunner IC and propose DF2755A as a potential therapeutic approach for the treatment of not only inflammatory painful conditions but also neuropathic ones and in particular non-Hunner IC/BPS.

The Role of Urinary VEGF in Observational Studies of BPS/IC Patients: A Systematic Review

Background: Bladder pain syndrome/interstitial cystitis (BPS/IC) is a chronic pain condition, often underdiagnosed, with an important impact on patient quality of life. More recently, an association between VEGF and its receptors has been suggested in BPS/IC pathophysiology, due to their role in promoting angiogenesis and inflammation, which can enhance bladder pain. Eventually, VEGF may be used as a biomarker for the diagnosis and prognostication of BPS/IC. To further clarify this issue, this review aims to critically summarize the available information, giving rise to a solid starting point for future studies. Methods: We systematically searched PubMed and Embase, using the queries “urinary VEGF”, “urinary VEGF” AND “pain”, “urinary VEGF” AND “lower urinary tract symptoms” and “urinary VEGF” AND “LUTS” from January 2016 to February 2022. Results: A total of 1026 papers were identified from which 7 articles were included in this study, which assessed 1036 participants. Regarding VEGF levels, overactive bladder (OAB) and healthy patients were used for comparison with BPS/IC patients. VEGF concentration seems to be higher when compared to healthy patients and overactive bladder (OAB) patients. Higher levels of VEGF were associated with pain severity, while a decrease in VEGF concentration was associated with pain and symptom improvement in women. However, these findings were not constant in all studies. Conclusions: There is a trend toward a relevant association between increased VEGF levels and pain or symptom severity in BPS/IC patients. Although there are some discrepancies among the studies and the number of patients included is small, VEGF and its receptors should be considered for future studies regarding its use in BPS/IC pathophysiology, diagnosis and prognostication.

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

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

Emerging molecular mechanisms and genetic targets for developing novel therapeutic strategies for treating bladder diseases

Bladder diseases affect millions of patients worldwide and compromise their quality of life with a substantial economic impact. The not fully understood aetiologies of bladder diseases limit the current diagnosis and therapeutic options to primarily symptomatic treatment. In addition, bladder targeted drug delivery is challenging due to its unique anatomical features and its natural physiological function of urine storage and frequent voiding. Therefore, current treatment options often fail to provide a highly effective, precisely targeted and long-lasting treatment. With the growing maturity of gene therapy, comprehensive studies are needed to provide a better understanding of the molecular mechanisms underpinning bladder diseases and help to identify novel gene therapeutic targets and biomarkers for treating bladder diseases. In this review, molecular mechanisms involved in pathology of bladder cancer, interstitial cystitis and overactive bladder syndrome are reviewed, with focus on establishing potential novel treatment options. Proposed novel therapies, including gene therapy combined with nanotechnology, localised drug delivery by nanoparticles, and probiotics, are discussed in regard to their safety profiles, efficacy, treatment lenght, precise targeting, and in comparison to conventional treatment methods.

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.

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.

Identification of novel biomarkers in Hunner's interstitial cystitis using the CIBERSORT, an algorithm based on machine learning

Background

 Hunner’s interstitial cystitis (HIC) is a complex disorder characterized by pelvic pain, disrupted urine storage, and Hunner lesions seen on cystoscopy. There are few effective diagnostic biomarkers. In the present study, we used the novel machine learning tool CIBERSORT to measure immune cell subset infiltration and potential novel diagnostic biomarkers for HIC.

Methods

The GSE11783 and GSE57560 datasets were downloaded from the Gene Expression Omnibus for analysis. Ten HIC and six healthy samples from GSE11783 were analyzed using the CIBERSORT algorithm. Gene Set Enrichment Analysis (GSEA) was performed to identify biological processes that occur during HIC pathogenesis. Finally, expression levels of 11 T cell follicular helper cell (Tfh) markers were compared between three healthy individuals and four patients from GSE57560.

Results

Six types of immune cells in HIC from GSE11783 showed significant differences, including resting mast cells, CD4⁺ memory-activated T cells (CD3⁺ CD4⁺ HLA-DR⁺ cells), M0 and M2 macrophages, Tfh cells, and activated natural killer cells. Except for plasma cells, there were no significant differences between Hunner’s lesion and non-Hunner’s lesion areas in HIC. The GSEA revealed significantly altered biological processes, including antigen–antibody reactions, autoimmune diseases, and infections of viruses, bacteria, and parasites. There were 11 Tfh cell markers with elevated expression in patients from GSE57560.

Conclusion

This was the first demonstration of Tfh cells and CD3⁺ CD4⁺ HLA-DR⁺ cells with elevated expression in HIC. These cells might serve as novel diagnostic biomarkers.

Supplementary Information

The online version contains supplementary material available at 10.1186/s12894-021-00875-8.

The effects of simulated childbirth trauma on the gene expression of neurotransmitter receptors in the bladder of female rats

BACKGROUND/PURPOSE

To investigate the effects of simulated childbirth on the gene expression of parasympathetic muscarinic, purinergic (P2X), and neurokinin receptors of lower urinary tract in rats.

METHODS

In all, twenty-four primiparous pregnant Sprague-Dawley female rats were equally divided into three groups: (1). Control group; 8 rats, (2) intra-vaginal balloon dilation for 2 h group; 8 rats, (3) and for 4 h group; 8 rats. After balloon dilatation for 4 months, all rats were sacrificed. We analyzed the gene expression of parasympathetic muscarinic, purinergic (P2X), and neurokinin receptors by real-time quantitative PCR (q-PCR). We quantified pro-inflammatory cytokines of TNF-α and IL-6 by Enzyme-linked immunosorbent assays (ELISA). The urodynamic parameters and micturition frequency by cystometry (CMG) were recorded.

RESULTS

Our results showed that the balloon dilation significantly increased micturition frequency and modified peak micturition pressure compare to those in the control groups. Balloon dilation significantly decreased voiding interval and bladder volume compared to those in the control groups. Gene expressions of M3 muscarinic, P2X3 purinergic receptors, and significantly increased following balloon dilation for 2 hours and 4 hours than those in the control group. In addition, we found that NK1R and NK3R receptors were significantly decreased after balloon dilation compare to control group. The marked increase of TNF-α and IL-6 were also seen in the 2 balloon groups.

CONCLUSION

The results of our study suggested that birth trauma may impair the function of urinary tract, this being partly related to the changes in the gene expression of the neurotransmitter receptors of the lower urinary tract.

Autoimmunity to urothelial antigen causes bladder inflammation, pelvic pain, and voiding dysfunction: a novel animal model for Hunner-type interstitial cystitis

Recent evidence revealed that Hunner-type interstitial cystitis (HIC) is a robust inflammatory disease potentially associated with enhanced immune responses and histologically characterized by epithelial denudation and lymphoplasmacytic infiltration with frequent clonal expansion of infiltrating B cells. To date, few animal models that reproduce the histological and clinical correlates of HIC have yet been established. In the present study, we aimed to develop a novel animal model for HIC via autoimmunity to the bladder urothelium using the transgenic mouse model (URO-OVA) that expresses the membrane form of the model antigen ovalbumin (OVA) as a self-antigen on the bladder urothelium. OVA-specific lymphocytes (splenocytes) were generated by immunization of C57BL/6 mice with OVA protein and injected intravenously into URO-OVA mice. The splenocytes from OVA-immunized C57BL/6 mice showed increased interferon (IFN)-γ production in response to OVA stimulation in vitro. URO-OVA mice adoptively transferred with OVA-primed splenocytes developed cystitis exhibiting histological chronic inflammatory changes such as remarkable mononuclear cell infiltration predominantly composed of T and B lymphocytes, increased vascularity, and mucosal hyperemia in the bladder at days 7-28 with a peak at day 21 tested. No systemic inflammation was found in cystitis-induced URO-OVA mice, nor was any inflammation found in wild-type C57BL/6 mice adoptively transferred with OVA-primed splenocytes. Along with bladder inflammation, URO-OVA mice demonstrated significantly increased pelvic nociceptive responses, voiding dysfunction, and upregulated mRNA expression levels for IFN-γ, tumor necrosis factor-α (TNF-α), and substance P precursor in the bladder. This model reproduces the histological and clinical features of human HIC, providing a novel model for HIC research.

Interstitial cystitis, bladder pain syndrome, hypersensitive bladder, and interstitial cystitis/bladder pain syndrome - clarification of definitions and relationships

Interstitial cystitis and interstitial cystitis-related conditions such as bladder pain syndrome and hypersensitive bladder have a similar symptomatic profile but probably different etiologies. A meaningful classification of these diseases/conditions is mandatory for clinical and investigational progress. The condition with Hunner lesions (Hunner type interstitial cystitis) is distinct from other categories in terms of histopathology, gene expression, and clinical management. Classification should clearly differentiate the presence or absence of Hunner lesions. The term covering patients as a whole should contain interstitial cystitis, since interstitial cystitis is historically a well-known name and used for insurance reimbursement. The proposed taxonomy features an umbrella term (interstitial cystitis/bladder pain syndrome) and two subgroups, Hunner type interstitial cystitis (with Hunner lesions) and bladder pain syndrome (without Hunner lesions). Interstitial cystitis/bladder pain syndrome is convenient for initial management, and subgroups can categorize the patients for specific management. The characteristic symptom profile is to be collectively termed as hypersensitive bladder symptoms.

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

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

A Randomized, Double-blind, Placebo-controlled Trial of Certolizumab Pegol in Women with Refractory Interstitial Cystitis/Bladder Pain Syndrome

BACKGROUND

Interstitial cystitis/bladder pain syndrome (IC/BPS) is a chronic, disabling bladder disease, with an uncertain pathophysiology and no universally effective treatment.

OBJECTIVE

To evaluate the efficacy and safety of certolizumab pegol compared with placebo in women with refractory IC/BPS.

DESIGN, SETTING, AND PARTICIPANTS

Eligible women, aged 18-65 yr with moderate to severe IC/BPS, were enrolled in this randomized, double-blind, placebo-controlled pilot study.

INTERVENTION

Study patients were randomized at a 2:1 ratio to receive either certolizumab pegol or placebo.

OUTCOME MEASUREMENTS AND STATISTICAL ANALYSIS

The primary outcome measure was a patient-reported global response assessment (GRA). Secondary endpoints included Interstitial Cystitis Symptom Index (ICSI), Interstitial Cystitis Problem Index (ICPI), and a numeric rating scale for pain and urgency.

RESULTS AND LIMITATIONS

The primary endpoint of GRA improvement at week 2 was not met. However, by week 18, there was significant improvement in GRA for certolizumab pegol compared with placebo in pain (odds ratio [OR]=17.3, p=0.002), urgency (OR=9.92, p=0.02), and overall symptoms (OR=15.0, p=0.006). At week 18, there was a statistically significant improvement for certolizumab pegol compared with placebo in change from baseline for ICSI of -3.6 (95% confidence interval [CI]: -6.9 to -0.29, p=0.03), ICPI of -3.0 (95% CI: -6.1 to 0.12, p=0.042), pain scale of -2.0 (95% CI: -3.9 to -0.15, p=0.02), and urgency scale of -1.7 (95% CI: -3.5 to 0.06, p=0.03). There was a significant difference in greater than 30% reduction in pain from baseline comparing certolizumab pegol with placebo at week 18 (OR=13.0, p=0.02). Limitations include a larger, longer, multicenter trial is warranted with phenotypic categorization of patients.

CONCLUSIONS

Women with moderate to severe refractory IC/BPS were more likely to experience significant improvement in symptoms with certolizumab pegol compared with placebo therapy. Further investigation of certolizumab pegol for the treatment of IC/BPS is warranted with a larger, longer, multicenter, randomized, placebo-controlled trial.

PATIENT SUMMARY

Women with moderate to severe interstitial cystitis/bladder pain syndrome were helped with a medication used to treat autoimmune diseases.

Pharmacological management of interstitial cystitis /bladder pain syndrome and the role cyclosporine and other immunomodulating drugs play

INTRODUCTION

Interstitial cystitis/bladder pain syndrome (IC/BPS) is a symptomatic disorder characterized by pelvic pain and urinary frequency. Immunological responses are considered as one of the possible etiologies of IC/BPS. In this review, we focused on emerging targets, especially on those modulating immunological mechanisms for the treatments of IC/BPS. Area covered: This review was based on the literature search of PubMed/MEDLINE, for which key words following bladder pain syndrome, interstitial cystitis, and/or cyclosporine A (CyA) were used. We discussed current treatments and the drugs targeting the immune responses including CyA and other drugs with different mechanisms including NGF antibodies and P2X3 antagonists. Expert commentary: IC/BPS is often difficult to treat by current treatments. Immunosuppression agents, especially CyA are considered as effective treatments for IC/BPS with Hunner's lesion because these drugs suppress the inflammatory responses in the bladder underlying urinary symptoms of the disease. Base on the previous literatures, we should use CyA for the refractory IC/BPS, especially that with Hunner's lesion due to its side effects. New drugs targeting other mechanisms such as urothelial or afferent nerve dysfunction or new delivery systems such as sustained drug releasing devices or gene therapy techniques may be promising for the future treatments of IC/BPS.

Expression and Function of Chemokines CXCL9-11 in Micturition Pathways in Cyclophosphamide (CYP)-Induced Cystitis and Somatic Sensitivity in Mice

Changes in urinary bladder function and somatic sensation may be mediated, in part, by inflammatory changes in the urinary bladder including the expression of chemokines. Male and female C57BL/6 mice were treated with cyclophosphamide (CYP; 75 mg/kg, 200 mg/kg, i.p.) to induce bladder inflammation (4 h, 48 h, chronic). We characterized the expression of CXC chemokines (CXCL9, CXCL10 and CXCL11) in the urinary bladder and determined the effects of blockade of their common receptor, CXCR3, at the level urinary bladder on bladder function and somatic (hindpaw and pelvic) sensation. qRT-PCR and Enzyme-Linked Immunoassays (ELISAs) were used to determine mRNA and protein expression of CXCL9, CXCL10 and CXCL11 in urothelium and detrusor. In urothelium of female mice treated with CYP, CXCL9 and CXCL10 mRNA significantly (p ≤ 0.01) increased with CYP treatment whereas CXC mRNA expression in the detrusor exhibited both increases and decreases in expression with CYP treatment. CXC mRNA expression urothelium and detrusor of male mice was more variable with both significant (p ≤ 0.01) increases and decreases in expression depending on the specific CXC chemokine and CYP treatment. CXCL9 and CXCL10 protein expression was significantly (p ≤ 0.01) increased in the urinary bladder with 4 h CYP treatment in female mice whereas CXC protein expression in the urinary bladder of male mice did not exhibit an overall change in expression. CXCR3 blockade with intravesical instillation of AMG487 (5 mg/kg) significantly (p ≤ 0.01) increased bladder capacity, reduced voiding frequency and reduced non-voiding contractions in female mice treated with CYP (4 h, 48 h). CXCR3 blockade also reduced (p ≤ 0.01) hindpaw and pelvic sensitivity in female mice treated with CYP (4 h, 48 h). CXC chemokines may be novel targets for treating urinary bladder dysfunction and somatic sensitization resulting from urinary bladder inflammation.

Endometriosis increased the risk of bladder pain syndrome/interstitial cystitis: A population-based study

OBJECTIVE

Previous studies have suggested an association between bladder pain syndrome/interstitial cystitis (BPS/IC) and endometriosis. However, no nation-wide population study has yet reported an association between them. In this study, we examined the risk of BPS/IC among subjects with endometriosis during a 3-year follow-up in Taiwan using a population-based dataset.

STUDY DESIGN

This study comprised 9191 subjects with endometriosis, and 27 573 subjects randomly selected as controls. We individually followed-up each subject (n = 36 764) for a 3-year period to identify subjects subsequently diagnosed with BPS/IC. A Cox proportional hazards regression model was employed to estimate the risk of subsequent BPS/IC following a diagnosis of endometriosis.

RESULTS

Incidences of BPS/IC during the 3-year follow-up period was 0.2% and 0.05% for subjects with and without endometriosis, respectively. The hazard ratio for developing BPS/IC over a 3-year period for subjects with endometriosis compared to subjects without endometriosis was 4.43 (95% CI: 2.13-9.23). After adjusting for co-morbidities like diabetes, hypertension, coronary heart disease, obesity, hyperlipidemia, chronic pelvic pain, irritable bowel syndrome, fibromyalgia, chronic fatigue syndrome, depression, panic disorder, migraines, sicca syndrome, allergies, endometriosis, asthma, tobacco use, and alcohol abuse, the Cox proportional hazards regressions revealed that the hazard ratio for BPS/IC among subjects with endometriosis was 3.74 (95% CI = 1.76-7.94, P < 0.001) compared to that in controls.

CONCLUSIONS

This study provides epidemiological evidence of an association between endometriosis and a subsequent diagnosis of BPS/IC.

Current Pharmacologic Approaches in Painful Bladder Research: An Update

The symptoms of interstitial cystitis (IC)/bladder pain syndrome (BPS) may have multiple causes and involve many contributing factors. Traditional treatments (intravesical instillations) have had a primary focus on the bladder as origin of symptoms without adequately considering the potential influence of other local (pelvic) or systemic factors. Systemic pharmacological treatments have had modest success. A contributing factor to the low efficacy is the lack of phenotyping the patients. Individualized treatment based on is desirable, but further phenotype categorization is needed. There seems to be general agreement that IC is a unique disease and that BPS is a syndrome with multiple pathophysiologies, but this has so far not been not been well reflected in preclinical research with the aim of finding new pharmacological treatments. Current research approaches, including anti-nerve growth factor treatment, anti-tumor necrosis factor-α treatment, activation of SHIP1 (AQX-1125), and P2X3 receptor antagonists, and α₁-adrenoceptor antagonists are potential systemic treatments, implying that not only the bladder is exposed to the administered drug, which may be beneficial if the IC/BPS is a bladder manifestation of a systemic disease, or negative (adverse effects) if it is a local bladder condition. Local treatment approaches such as the antagonism of Toll-like receptors (which still is only experimental) and intravesical liposomes (with positive proof-of-concept), may have the advantages of a low number of systemic adverse effects, but cannot be expected to have effects on symptoms generated outside the bladder. Assessment of which of the treatment approaches discussed in this review that can be developed into useful therapies requires further studies.

Development of an interstitial cystitis risk score for bladder permeability

BACKGROUND

Interstitial cystitis/bladder pain syndrome (IC) is a multifactorial syndrome of severe pelvic and genitalia pain and compromised urinary function; a subset of IC patients present with Hunner's lesions or ulcers on their bladder walls (UIC). UIC is diagnosed by cystoscopy, which may be quite painful. The objective of this study was to determine if a calculated Bladder Permeability Defect Risk Score (BP-RS) based on non-invasive urinary cytokines could discriminate UIC patients from controls and IC patients without Hunner's ulcers.

METHODS

A national crowdsourcing effort targeted IC patients and age-matched controls to provide urine samples. Urinary cytokine levels for GRO, IL-6, and IL-8 were determined using a Luminex assay.

RESULTS

We collected 448 urine samples from 46 states consisting of 153 IC patients (147 female, 6 male), of which 54 UIC patients (50 females, 4 male), 159 female controls, and 136 male controls. A defined BP-RS was calculated to classify UIC, or a bladder permeability defect etiology, with 89% validity.

CONCLUSIONS

The BP-RS Score quantifies UIC risk, indicative of a bladder permeability defect etiology in a subset of IC patients. The Bladder Permeability Defect Risk Score is the first validated urine biomarker assay for interstitial cystitis/bladder pain syndrome.

Diagnostic value of urinary CXCL10 as a biomarker for predicting Hunner type interstitial cystitis

AIM

To investigate the feasibility of chemokines and cytokines potentially elevated in the bladder tissue of Hunner type interstitial cystitis (HIC) as urinary markers for distinguishing HIC from non-Hunner type interstitial cystitis (NHIC) METHODS: Urine specimens were collected from 41 HIC patients, 25 NHIC patients, and 31 healthy volunteers (control). The supernatants of urine specimens were subjected to ELISA kits for measurements of 10 cytokines and chemokines, whose gene expression was known to be elevated in HIC bladder tissue. Urinary levels normalized by urinary creatinine (Cr) concentration were compared among three groups. Efficiency in differentiating IC and IC subtypes was explored by ROC analysis. The correlation of marker levels with symptom severity, assessed by O'Leary-Sant's symptom index (OSSI) and problem index (OSPI), was examined.

RESULTS

The urinary levels of CXCL10 and NGF were significantly higher in HIC than NHIC. CXCL10 and NGF differentiated HIC against NHIC with AUC of 0.78 and 0.68, respectively. Combination of CXCL10 and NGF levels yielded an AUS of 0.81. The CXCL10 cut-off of 53.2 pg/mg Cr had sensitivity of 46.1%, specificity of 93.7%, positive predictive value of 97.7%, and negative predictive value of 60.0%. The urinary level of other cytokines showed no significant difference between HIC and NHIC. Significant correlation with symptoms was detected for CXCL10 alone.

CONCLUSION

The results suggested that increased urinary level of CXCL10 combined with or without high NGF level could be a promising supplementary biomarker for differentiating HIC from NHIC with modest sensitivity and high specificity.

Expression profile of urothelial transcription factors in bladder biopsies with interstitial cystitis

OBJECTIVES

To characterize interstitial cystitis pathology based on the expression profile of urothelial tissue-specific master transcription factors.

METHODS

Bladder carcinoma cell lines derived from the urothelial stem cells (epithelial or mesenchymal) were used to identify candidate urothelial master transcription factors. Gene expression was measured with quantitative reverse transcription polymerase chain reaction. From the initial screening of 170 transcription factors (human homologs of Drosophila segmentation genes and known master transcription factors from a database), 28 transcription factors were selected. Subsequently, messenger ribonucleic acid from bladder biopsies of interstitial cystitis patients was purified, and gene expression levels of known urothelial marker genes and candidate master transcription factors were measured. Multivariate expression data were analyzed with spss software.

RESULTS

Factor analysis decomposed the expression profile into four axes: principal axis 1 included retinoic acid receptors and 17 candidate master transcription factors. Principal axis 2 included KRT5 and five candidates. Principal axis 3 included transcription factor TP63 and two candidates. Principal axis 4 included SHH and two candidates. Principal component analysis segregated biopsies from Hunner's lesion in the principal component 1 (retinoic acid)/principal component 2 (SOX13)/principal component 3 (TP63) space.

CONCLUSIONS

Urothelial master transcription factors could serve as novel diagnostic markers and potentially explain the molecular pathology of interstitial cystitis.

Implications for bidirectional signaling between afferent nerves and urothelial cells-ICI-RS 2014

AIMS

To present a synopsis of the presentations and discussions from Think Tank I, "Implications for afferent-urothelial bidirectional communication" of the 2014 International Consultation on Incontinence-Research Society (ICI-RS) meeting in Bristol, UK.

METHODS

The participants presented what is new, currently understood or still unknown on afferent-urothelial signaling mechanisms. New avenues of research and experimental methodologies that are or could be employed were presented and discussed.

RESULTS

It is clear that afferent-urothelial interactions are integral to the regulation of normal bladder function and that its disruption can have detrimental consequences. The urothelium is capable of releasing numerous signaling factors that can affect sensory neurons innervating the suburothelium. However, the understanding of how factors released from urothelial cells and afferent nerve terminals regulate one another is incomplete. Utilization of techniques such as viruses that genetically encode Ca(2+) sensors, based on calmodulin and green fluorescent protein, has helped to address the cellular mechanisms involved. Additionally, the epithelial-neuronal interactions in the urethra may also play a significant role in lower urinary tract regulation and merit further investigation.

CONCLUSION

The signaling capabilities of the urothelium and afferent nerves are well documented, yet how these signals are integrated to regulate bladder function is unclear. There is unquestionably a need for expanded methodologies to further our understanding of lower urinary tract sensory mechanisms and their contribution to various pathologies.

Pathomechanism of Interstitial Cystitis/Bladder Pain Syndrome and Mapping the Heterogeneity of Disease

Interstitial cystitis/bladder pain syndrome (IC/BPS) is a heterogeneous syndrome which is usually characterized by urinary frequency, nocturia, and bladder pain. Several pathomechanisms have been proposed, including uroepithelial dysfunction, mast cell activation, neurogenic inflammation, autoimmunity, and occult urinary tract infections. It is possible that an inflammatory process alters regulation of urothelial homeostasis and results in dysfunction of the bladder epithelium. Different phenotypes of IC/BPS have been explored including Hunner and non-Hunner type IC, hypersensitive bladder, and bladder pain both with and without functional somatic syndrome. Different gene expressions have also been found in different IC phenotypes. Abnormal expressions of uroplakin, chondroitin sulfate and adhesive protein E-cadherin, tight junction protein zonula occludens-1 in IC/BPS bladder suggest abnormal epithelial differentiation in this bladder disease. Analysis of inflammatory proteins, or cytokines in the urine or serum provides another diagnostic foundation forIC/BPS subtypes. The involvement of IC/BPS in systemic functional somatic syndrome and other pelvic organ diseases might also subdivide subtypes of IC/BPS. Chronic inflammation, increased urothelial apoptosis, and abnormal urothelial function are closely associated in IC bladders. This article reviews recent research on the pathomechanisms of IC, which might help us in mapping the heterogeneity of the disease.

Update on Urinary Tract Markers in Interstitial Cystitis/Bladder Pain Syndrome

Interstitial cystitis (IC)/painful bladder syndrome/bladder pain syndrome (BPS) is a chronic hypersensory condition of unknown etiology. Moreover, the optimal modality for diagnosing IC remains disputed. Several urinary markers have been investigated that may have potential utility in the diagnosis or confirmation of IC/BPS. Thus, inflammatory mediators, proteoglycans, urinary hexosamines, proliferative factors, nitric oxide (NO), BK polyomavirus family, and urothelial proinflammatory gene analysis have been found to correlate with varying degrees with the clinical diagnosis or cystoscopic findings in patients with IC/BPS. The most promising urinary biomarker for IC/BPS is antiproliferative factor, a sialoglycopeptide that has demonstrated inhibitory effects on urothelial cell proliferation and a high sensitivity and specificity for IC/BPS symptoms and clinical findings. In this article, we review the urinary markers, possible future therapies for IC/BPS, and the clinical relevance and controversies regarding the diagnosis of IC/BPS.

Increased CXCR3 Expression of Infiltrating Plasma Cells in Hunner Type Interstitial Cystitis

An up-regulated CXCR3 pathway and affluent plasma cell infiltration are characteristic features of Hunner type interstitial cystitis (HIC). We further examined these two features using bladder biopsy samples taken from 27 patients with HIC and 15 patients with non-IC cystitis as a control. The number of CD3-positive T lymphocytes, CD20-positive B lymphocytes, CD138-positive plasma cells, and CXCR3-positive cells was quantified by digital image analysis. Double-immunofluorescence for CXCR3 and CD138 was used to detect CXCR3 expression in plasma cells. Correlations between CXCR3 positivity and lymphocytic and plasma cell numbers and clinical parameters were explored. The density of CXCR3-positive cells showed no significant differences between HIC and non-IC cystitis specimens. However, distribution of CXCR3-positivity in plasma cells indicated co-localization of CXCR3 with CD138 in HIC specimens, but not in non-IC cystitis specimens. The number of CXCR3-positive cells correlated with plasma cells in HIC specimens alone. Infiltration of CXCR3-positive cells was unrelated to clinical parameters of patients with HIC. These results suggest that infiltration of CXCR3-positive plasma cells is a characteristic feature of HIC. The CXCR3 pathway and specific immune responses may be involved in accumulation/retention of plasma cells and pathophysiology of the HIC bladder.

Clinical guidelines for interstitial cystitis and hypersensitive bladder updated in 2015

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

Investigational drugs for bladder pain syndrome (BPS) / interstitial cystitis (IC)

INTRODUCTION

Bladder pain syndrome (BPS)/interstitial cystitis (IC) is associated with sensory lower urinary tract symptoms. Unfortunately, many of the existing oral treatments are ineffective in most patients of BPS/IC, which is the motivation for developing new drugs and therapeutic approaches. This review covers the latest drugs that have been investigated in BPS/IC patients. Intravesical treatments offer the opportunity to directly target the painful bladder with less systemic side effects.

AREAS COVERED

In this review, the authors analyze the existing literature supporting the treatment of BPS/IC with conventional drugs including heparin, hyaluronic acid, chondroitin sulfate, and dimethylsulfoxide (DMSO). Furthermore, investigational drugs such as tanezumab and adalimumab, capable of sequestering nerve growth factor (NGF), and Tumor necrosis factor-α (TNF- α) are discussed. Investigational treatments such as liposomes, botulinum toxin (BTX), liposomal BTX, PD-0299685 (a Ca(2+) channel ɑ2δ ligand), continuous intravesical lidocaine, and AQX-1125 (a novel SHIP1 activating compound) are also covered.

EXPERT OPINION

New investigational drugs offer promising improvements in clinical outcomes for BPS/IC patients; however, BPS/IC is a chronic pain disorder that is very vulnerable to a strong placebo effect. In addition, BPS/IC is a heterogeneous disorder that can be classified into several phenotypes. Since different phenotypes of BPS/IC respond differently to systemic and intravesical treatments, the authors believe that new drugs developed for BPS/IC are more likely to meet their predetermined clinical endpoints if the inclusion/exclusion criterion is tailored to specific phenotype of BPS/IC patients.

Inflammasomes are important mediators of prostatic inflammation associated with BPH

Background

There is mounting evidence to support the role of inflammation in benign prostate hyperplasia (BPH), and a recent study reported expression of inflammasome derived cytokine IL-18 in prostate biopsy of BPH patients. Here we examined the expression of inflammasome-derived cytokines and activation of nucleotide-binding oligomerization domain-like receptor with pyrin domain protein 1 (NLRP) 1 inflammasome in a rat model of prostatic inflammation relevant to BPH.

Methods

Prostatic inflammation was experimentally induced in three-month-old male Sprague–Dawley rats by intraprostatic injection (50 μL) of either 5 % formalin or saline (sham) into the ventral lobes of prostate. 7 days later, prostate and bladder tissue was harvested for analysis of inflammasome by Western blot, immunohistochemistry and downstream cytokine production by Milliplex.

Results

Expression of interleukins, CXC and CC chemokines were elevated 2-15 fold in formalin injected prostate relative to sham. Significant expression of NLRP1 inflammasome components and caspase-1 in prostate were associated with significant elevation of pro and cleaved forms of IL-1β (25.50 ± 1.16 vs 3.05 ± 0.65 pg/mg of protein) and IL-18 (1646.15 ± 182.61 vs 304.67 ± 103.95 pg/mg of protein). Relative to prostate tissue, the cytokine expression in bladder tissue was much lower and did not involve inflammasome activation.

Conclusions

Significant upregulation of NLRP1, caspase-1 and downstream cytokines (IL-18 and IL-1β) suggests that a NLRP1 inflammasome is assembled and activated in prostate tissue of this rat model. Recapitulation of findings from human BPH specimens suggests that the inflammasome may perpetuate the inflammatory state associated with BPH. Further clarification of these pathways may offer innovative therapeutic targets for BPH-related inflammation.

Bladder afferent hyperexcitability in bladder pain syndrome/interstitial cystitis

Bladder pain syndrome/interstitial cystitis is a disease with lower urinary tract symptoms, such as bladder pain and urinary frequency, which results in seriously impaired quality of life of patients. The extreme pain and urinary frequency are often difficult to treat. Although the etiology of bladder pain syndrome/interstitial cystitis is still not known, there is increasing evidence showing that afferent hyperexcitability as a result of neurogenic bladder inflammation and urothelial dysfunction is important to the pathophysiological basis of symptom development. Further investigation of the pathophysiology will lead to the effective treatment of patients with bladder pain syndrome/interstitial cystitis.

Hypersensitive bladder: a solution to confused terminology and ignorance concerning interstitial cystitis

Taxonomy or nomenclature concerning interstitial cystitis and its related symptom syndromes is in a state of confusion. After analyzing the reasons for confusion in regard to three components (disease name, symptoms, Hunner's lesion), I would like to propose a new term, "hypersensitive bladder", taking after overactive bladder, as a solution. Hypersensitive bladder symptoms are defined as "increased bladder sensation, usually associated with urinary frequency and nocturia, with or without bladder pain." The proposal of hypersensitive bladder is based on: (i) it does not appear a symptom syndrome, but a disease by ending with an organ name, "bladder"; (ii) it does not contain confusable symptom terms (pain and urgency), but indicates irritative symptoms including pain and urgency; and (iii) it suggests pathophysiological hyperactivity of sensory nerves. Interstitial cystitis is defined by three requirements: (i) hypersensitive bladder symptoms; (ii) bladder pathology; and (iii) no other diseases, where bladder pathology should be clearly stated either as Hunner's lesion or glomerulations after hydrodistention. Hypersensitive bladder can be used for the condition with hypersensitive bladder symptoms, but no obvious disease explaining hypersensitive bladder symptoms identified. Interstitial cystitis is a representative disease causing hypersensitive bladder symptoms, most typically with pain, but might be painless and indistinguishable from overactive bladder. Introducing hypersensitive bladder as a counter concept of overactive bladder into bladder dysfunction taxonomy will facilitate clinical practice and research progress, and attract considerable attention from the medical world.

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

OBJECTIVES

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

METHODS

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

RESULTS

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

CONCLUSION

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

Potential urine and serum biomarkers for patients with bladder pain syndrome/interstitial cystitis

There is a lack of consensus on the pathophysiology of bladder pain syndrome/interstitial cystitis. The chronic pain symptoms of bladder pain syndrome/interstitial cystitis refractory to local treatment could be a result of central nervous system sensitization and persisting abnormalities in the bladder wall, which activate the afferent sensory system. Evidence also shows that bladder pain syndrome/interstitial cystitis is a heterogeneous syndrome and that the two subtypes, the ulcerative (classic) and non-ulcerative types, represent different disease entities. There is a need for non-invasive markers for the differential diagnoses of the subtypes of bladder pain syndrome/interstitial cystitis, and between bladder pain syndrome/interstitial cystitis and bladder sensory disorders, such as hypersensitive bladder syndrome or overactive bladder. Bladder pain syndrome/interstitial cystitis, but not overactive bladder, involves an aberrant differentiation program in the bladder urothelium that leads to altered synthesis of several proteoglycans, cell adhesion and tight junction proteins, and bacterial defense molecules. These findings have led to the rationale for identifying urinary biomarkers to detect bladder pain syndrome/interstitial cystitis in patients with frequency urgency syndrome. Recently, the markers that have been the focus of the most research are antiproliferative factor, epidermal growth factor, heparin-binding epidermal growth factor, glycosaminoglycans and bladder nitric oxide. In addition, inflammatory proteins in the urine and serum play important roles in the pathogenesis of bladder pain syndrome/interstitial cystitis. The urinary proteome is an easily accessible source of biomarkers for differentiation between inflammatory bladder disorders. Analysis of multiple urinary proteins and serum cytokines could provide a diagnostic basis for bladder pain syndrome/interstitial cystitis, and could be a tool for the differential diagnosis of bladder pain syndrome/interstitial cystitis and other sensory bladder disorders.

Tumor necrosis factor superfamily in innate immunity and inflammation

The tumor necrosis factor superfamily (TNFSF) and its corresponding receptor superfamily (TNFRSF) form communication pathways required for developmental, homeostatic, and stimulus-responsive processes in vivo. Although this receptor-ligand system operates between many different cell types and organ systems, many of these proteins play specific roles in immune system function. The TNFSF and TNFRSF proteins lymphotoxins, LIGHT (homologous to lymphotoxins, exhibits inducible expression, and competes with HSV glycoprotein D for herpes virus entry mediator [HVEM], a receptor expressed by T lymphocytes), lymphotoxin-β receptor (LT-βR), and HVEM are used by embryonic and adult innate lymphocytes to promote the development and homeostasis of lymphoid organs. Lymphotoxin-expressing innate-acting B cells construct microenvironments in lymphoid organs that restrict pathogen spread and initiate interferon defenses. Recent results illustrate how the communication networks formed among these cytokines and the coreceptors B and T lymphocyte attenuator (BTLA) and CD160 both inhibit and activate innate lymphoid cells (ILCs), innate γδ T cells, and natural killer (NK) cells. Understanding the role of TNFSF/TNFRSF and interacting proteins in innate cells will likely reveal avenues for future therapeutics for human disease.

Lipocalin2 as a plasma marker for tumors with hypoxic regions

Hypoxic tumors have been identified as appropriate indicators of tumor malignancy. However, no convenient plasma marker for hypoxic tumors has been described. Therefore, to identify a novel, convenient plasma marker for hypoxic tumors, we used microarray analysis to compare gene expression profiles of normoxic and hypoxic tumor tissues of mice bearing melanomas. Among the upregulated genes detected in hypoxic tumors, we chose to study the secretory protein lipocalin2 (LCN2) as a marker for hypoxic tumors. LCN2 protein levels in the plasma of mice bearing hypoxic tumors were significantly increased compared with those in mice bearing normoxic tumors. Interestingly, LCN2 mRNA levels were 17-fold higher in HIF-1α-positive hypoxic tumors than in HIF-1α-negative normoxic tumors. Furthermore, LCN2 mRNA levels were significantly higher in the B16-F1 cells and various human tumor cells cultured under hypoxic conditions than in cells cultured under normoxic conditions, while no changes in mRNA expression were observed in nontumor NIH-3T3 cells, even under hypoxic conditions. In cultured cells, the expression pattern of LCN2 was mostly consistent with that of HIF-1α, whereas that of a conventional hypoxic marker, carbonic anhydrase IX, was not. Collectively, our data suggested that LCN2 was a useful plasma marker for hypoxic tumors.

Urinary nerve growth factor could be a biomarker for interstitial cystitis/painful bladder syndrome: a meta-analysis

To examine whether urinary nerve growth factor (NGF) could serve as a biomarker for interstitial cystitis/painful bladder syndrome (IC/PBS), we conducted a comprehensive meta-analysis of 9 studies. Among the studies considered, patients with IC/PBS had higher urinary NGF and NGF/Cr levels compared to those of healthy people (SMD = 1.94, 95%CI = 0.79-3.08, P = 0.0009 and SMD = 1.79, 95%CI = 0.65-2.93, P = 0.002, respectively). In addition, there was a significant difference between patients with IC/PBS and patients with overactive bladder (OAB) symptoms with respect to the urinary NGF and NGF/Cr levels (SMD = -0.62, 95%CI = -1.00--0.24, P = 0.001 and SMD = -0.70, 95%CI = -1.01--0.39, P<0.0001, respectively). Furthermore, patients had a significantly lower urinary NGF level after successful treatment (SMD = 1.74, 95%CI = 0.32-3.17, P = 0.02). In conclusion, urinary NGF could be a useful biomarker for the diagnosis of OAB, a urinary biomarker for the differential diagnosis of IC/PBS and OAB (when a critical urinary NGF or NGF/Cr level is needed), and a predictive biomarker to help guide treatment.

Correlation of gene expression with bladder capacity in interstitial cystitis/bladder pain syndrome

PURPOSE

Interstitial cystitis and bladder pain syndrome are terms used to describe a heterogeneous chronic pelvic and bladder pain disorder. Despite its significant prevalence, our understanding of disease etiology is poor. We molecularly characterized interstitial cystitis/bladder pain syndrome and determined whether there are clinical factors that correlate with gene expression.

MATERIALS AND METHODS

Bladder biopsies from female subjects with interstitial cystitis/bladder pain syndrome and female controls without signs of the disease were collected and divided into those with normal and low anesthetized bladder capacity, respectively. Samples then underwent RNA extraction and microarray assay. Data generated by these assays were analyzed using Omics Explorer (Qlucore, Lund, Sweden), GeneSifter® Analysis Edition 4.0 and Ingenuity® Pathway Analysis to determine similarity among samples within and between groups, and measure differentially expressed transcripts unique to each phenotype.

RESULTS

A total of 16 subjects were included in study. Principal component analysis and unsupervised hierarchical clustering showed clear separation between gene expression in tissues from subjects with low compared to normal bladder capacity. Gene expression in tissue from patients with interstitial cystitis/bladder pain syndrome who had normal bladder capacity did not significantly differ from that in controls without interstitial cystitis/bladder pain syndrome. Pairwise analysis revealed that pathways related to inflammatory and immune response were most involved.

CONCLUSIONS

Microarray analysis provides insight into the potential pathological condition underlying interstitial cystitis/bladder pain syndrome. This pilot study shows that patients with this disorder who have low compared to normal bladder capacity have significantly different molecular characteristics, which may reflect a difference in disease pathophysiology.

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

PURPOSE

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

MATERIALS AND METHODS

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

RESULTS

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

CONCLUSIONS

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

The role(s) of cytokines/chemokines in urinary bladder inflammation and dysfunction

Bladder pain syndrome (BPS)/interstitial cystitis (IC) is a chronic pain syndrome characterized by pain, pressure, or discomfort perceived to be bladder related and with at least one urinary symptom. It was recently concluded that 3.3-7.9 million women (>18 years old) in the United States exhibit BPS/IC symptoms. The impact of BPS/IC on quality of life is enormous and the economic burden is significant. Although the etiology and pathogenesis of BPS/IC are unknown, numerous theories including infection, inflammation, autoimmune disorder, toxic urinary agents, urothelial dysfunction, and neurogenic causes have been proposed. Altered visceral sensations from the urinary bladder (i.e., pain at low or moderate bladder filling) that accompany BPS/IC may be mediated by many factors including changes in the properties of peripheral bladder afferent pathways such that bladder afferent neurons respond in an exaggerated manner to normally innocuous stimuli (allodynia). The goals for this review are to describe chemokine/receptor (CXCL12/CXCR4; CCL2/CCR2) signaling and cytokine/receptor (transforming growth factor (TGF-β)/TGF-β type 1 receptor) signaling that may be valuable LUT targets for pharmacologic therapy to improve urinary bladder function and reduce somatic sensitivity associated with urinary bladder inflammation.