Identification of Molecular Mechanisms in Radiation Cystitis: Insights from RNA Sequencing.

Pelvic cancer survivors who were treated with radiation therapy are at risk for developing (hemorrhagic) radiation cystitis (RC) many years after completion of radiation therapy. Patients with RC suffer from lower urinary tract symptoms, including frequency, nocturia, pelvic pain, and incontinence. In advanced stages, hematuria can occur, potentially escalating to life-threatening levels. Current therapeutic options for RC are limited, partly due to ethical concerns regarding bladder biopsy in patients with fragile bladder tissue. This study aimed to leverage our established preclinical model to elucidate the molecular pathways implicated in radiation-induced tissue changes in the bladder. Female C57Bl/6 mice received a single dose of 40 Gy using CT-guided imaging and a two-beam irradiation approach using the SARRP irradiator. Bladders from irradiated and age-matched littermate controls were harvested at 1 week [n = 5/group] or 6 months [n = 5/group] after irradiation, RNA was harvested, and mRNA sequencing was performed at paired-end 150bp on the Illumina NovaSeq6000 with a target of 30 million reads per sample. Following RNA sequencing, thorough bioinformatics analysis was performed using iPathwayGuide v2012 (ADVAITA Bioinformatics). Findings of the RNA sequencing were validated using qPCR analysis. At 1 week post-irradiation, altered gene expression was detected in genes involved in DNA damage response, apoptosis, and transcriptional regulation. By 6 months post-irradiation, significant changes in gene expression were observed in inflammation, collagen catabolism, and vascular health. Affected pathways included the p53, JAK-STAT, and PI3K-Akt pathways. These findings were validated in vivo in bladder tissues from our preclinical model. This is the first study to determine the molecular changes in the bladder in response to radiation treatment. We have successfully pinpointed several pathways and specific genes that undergo modification, thereby contributing to the progression of radiation cystitis. These insights enhance our understanding of the pathophysiology of radiation cystitis and may ultimately pave the way to the identification of potential new therapeutic targets.

Purine nucleoside phosphorylase inhibition is an effective approach for the treatment of chemical hemorrhagic cystitis.

Hemorrhagic cystitis may be induced by infection, radiation therapy, or medications or may be idiopathic. Along with hemorrhagic features, symptoms include urinary urgency and frequency, dysuria (painful urination), and visceral pain. Cystitis-induced visceral pain is one of the most challenging types of pain to treat, and an effective treatment would address a major unmet medical need. We assessed the efficacy of a purine nucleoside phosphorylase inhibitor, 8-aminoguanine (8-AG), for the treatment of hemorrhagic/ulcerative cystitis. Lower urinary tract (LUT) function and structure were assessed in adult Sprague-Dawley rats, treated chronically with cyclophosphamide (CYP; sacrificed day 8) and randomized to daily oral treatment with 8-AG (begun 14 days prior to CYP induction) or its vehicle. CYP-treated rats exhibited multiple abnormalities, including increased urinary frequency and neural mechanosensitivity, reduced bladder levels of inosine, urothelial inflammation/damage, and activation of spinal cord microglia, which is associated with pain hypersensitivity. 8-AG treatment of CYP-treated rats normalized all observed histological, structural, biochemical, and physiological abnormalities. In cystitis 8-AG improved function and reduced both pain and inflammation likely by increasing inosine, a tissue-protective purine metabolite. These findings demonstrate that 8-AG has translational potential for reducing pain and preventing bladder damage in cystitis-associated LUT dysfunctions.

Uroprotective Potential of Campesterol in Cyclophosphamide Induced Interstitial Cystitis; Molecular Docking Studies.

Cyclophosphamide (CYP) is commonly used to treat cancer of the ovaries, breast, lymph, and blood system and produces interstitial cystitis (IC) via its urotoxic metabolite: i. e., acrolein. The present study was aimed to investigate the uroprotective effect of campesterol (a steroidal phytochemical) in cyclophosphamide induced IC. IC was induced by CYP (150 mg/kg, i. p.) in rats. The Enzyme linked immunosorbent assays for oxidative stress markers and Polymerase Chain Reaction (PCR) for inflammatory cytokines were carried out. The Tissue Organ Bath Technique was used for the evaluation of the spasmolytic effect of campesterol. Different pharmacological antagonists have been used to explore the mechanism of action of campesterol. Treatment with campesterol (70 mg/kg) reduced nociception (55 %), edema (67 %), hemorrhage (67 %), and protein leakage significantly (94 %). The antioxidant activity of campesterol was exhibited by a fall in MDA, NO, and an elevation in SOD, CAT, and GPX levels. Campesterol presented anti-inflammatory potential by decreasing IL-1, TNF-α, and TGF-ß expression levels. Histologically, it preserved urothelium from the deleterious effect of CYP. Campesterol showed a spasmolytic effect by reducing bladder overactivity that was dependent on muscarinic receptors, voltage-gated calcium and KATP channels, and cyclo-oxygenase pathways. In silico studies confirmed the biochemical findings. The findings suggest that campesterol could be valorized as a possible therapeutic agent against cyclophosphamide-induced interstitial cystitis.

Uro-protective role of chrysin against cyclophosphamide-induced hemorrhagic cystitis in rats involving the turning-off NF-κB/P38-MAPK, NO/PARP-1 and STAT-3 signaling cascades.

BACKGROUND: Chemotherapeutic agents are used to treat a wide range of cancer types, but they cause serious side effects which must be managed after treatment. Cyclophosphamide (CYP) is one of chemotherapeutic drugs that causes hemorrhagic cystitis (HC) induced by acrolein. OBJECTIVE: The current investigation intended to uncover the role of chrysin (CHR) in CYP-induced HC in rats and explore the signaling pathway beyond this effect. ANALYSIS: process: A single dose of CYP (200 mg/kg/IP) was injected, meanwhile CHR (25, 50 and 100 mg/kg, P.O) was administered respectively for 7 days prior to CYP administration and resume for 7 days afterwards. Urinary bladder tissue was then isolated from all rats to assess oxidative stress and inflammatory biomarkers. Moreover, histopathological examinations were performed. RESULTS: Treatment with CHR showed a marked alleviation in oxidative stress biomarkers induced by CYP. Furthermore, CHR treatment presented a dose-dependent boost in the anti-inflammatory; IL-10 levels and a drop in the pro-inflammatory biomarkers; IL-1ß, IL-6, and TNF-α. Additionally, stabilization of the PARP-1 protein expression was also detected thus preventing DNA damage. Similarly, CHR restored the urinary bladder cGMP levels. Notably, CHR treatment was accompanied with inhibition in NF-κB/p38-MAPK, NO/PARP-1 and STAT-3 signaling pathways inflammatory cascades. All these findings conformed with the histopathological examinations as well as iNOS immunostaining in the urinary bladder tissue. CONCLUSION: Co-administration of CHR and CYP attained uro-protective therapeutic potential to guard against HC as well as spot the tangled mechanism of CHR in attenuating the HC induced by CYP.

Escherichia coli-associated follicular cystitis in dogs: Clinical and pathologic characterization.

BACKGROUND: Follicular cystitis is an uncommon inflammatory change in the urinary bladder wall characterized by the formation of tertiary lymphoid structures (TLSs) in the submucosa. OBJECTIVES: To characterize clinical and pathologic features of follicular cystitis in dogs and to explore in situ distribution and possible role of Escherichia coli as an associated cause. ANIMALS: Eight dogs diagnosed with follicular cystitis and 2 control dogs. METHODS: Retrospective descriptive study. Dogs diagnosed with follicular cystitis (macroscopic follicular lesions in the urinary bladder mucosa and histopathologic detection of TLSs in bladder wall biopsies) were identified from medical records. Paraffin embedded bladder wall biopsies were subject to in situ hybridization for E. coli 16SrRNA identification. RESULTS: Follicular cystitis was diagnosed in large breed (median weight 24.9 kg, interquartile range [IQR] 18.8-35.4 kg) female dogs with a history of chronic recurrent urinary tract infections (UTIs; median duration of clinical signs 7 months, IQR 3-17 months; median number of previous UTIs 5, IQR 4-6). Positive E. coli 16SrRNA signal was detected within developing, immature and mature TLSs in 7/8 dogs, through submucosal stroma in 8/8 dogs and within the urothelium in 3/8 dogs. CONCLUSIONS AND CLINICAL IMPORTANCE: Chronic inflammation associated with an intramural E. coli infection in the urinary bladder wall represents a possible triggering factor for the development of follicular cystitis.

[8] and [10]-Gingerol reduces urothelial damage in ifosfamide-induced hemorrhagic cystitis via JAK/STAT/FOXO signaling pathway via IL-10.

Acrolein is the main toxic metabolite of ifosfamide (IFO) that causes urothelial damage by oxidative stress and inflammation. Here, we investigate the molecular mechanism of action of gingerols, Zingiber officinale bioactive molecules, as an alternative treatment for ifosfamide-induced hemorrhagic cystitis. Female Swiss mice were randomly divided into 5 groups: control; IFO; IFO + Mesna; and IFO + [8]- or [10]-gingerol. Mesna (80 mg/kg, i.p.) was given 5 min before, 4 and 8 h after IFO (400mg/kg, i.p.). Gingerols (25 mg/kg, p.o.) were given 1 h before and 4 and 8 h after IFO. Animals were euthanized 12 h after IFO injection. Bladders were submitted to macroscopic and histological evaluation. Oxidative stress and inflammation were assessed by malondialdehyde (MDA) or myeloperoxidase assays, respectively. mRNA gene expression was performed to evaluate mesna and gingerols mechanisms of action. Mesna was able to protect bladder tissue by activating NF-κB and NrF2 pathways. However, we demonstrated that gingerols acted as an antioxidant and anti-inflammatory agent stimulating the expression of IL-10, which intracellularly activates JAK/STAT/FOXO signaling pathway.

Micro-mechanical fingerprints of the rat bladder change in actinic cystitis and tumor presence.

Tissue mechanics determines tissue homeostasis, disease development and progression. Bladder strongly relies on its mechanical properties to perform its physiological function, but these are poorly unveiled under normal and pathological conditions. Here we characterize the mechanical fingerprints at the micro-scale level of the three tissue layers which compose the healthy bladder wall, and identify modifications associated with the onset and progression of pathological conditions (i.e., actinic cystitis and bladder cancer). We use two indentation-based instruments (an Atomic Force Microscope and a nanoindenter) and compare the micromechanical maps with a comprehensive histological analysis. We find that the healthy bladder wall is a mechanically inhomogeneous tissue, with a gradient of increasing stiffness from the urothelium to the lamina propria, which gradually decreases when reaching the muscle outer layer. Stiffening in fibrotic tissues correlate with increased deposition of dense extracellular matrix in the lamina propria. An increase in tissue compliance is observed before the onset and invasion of the tumor. By providing high resolution micromechanical investigation of each tissue layer of the bladder, we depict the intrinsic mechanical heterogeneity of the layers of a healthy bladder as compared with the mechanical properties alterations associated with either actinic cystitis or bladder tumor.

Bladder Mucosal Cystitis Cystica Lesions Are Tertiary Lymphoid Tissues That Correlate With Recurrent Urinary Tract Infection Frequency in Postmenopausal Women.

PURPOSE: We identify correlates and clinical outcomes of cystitis cystica, a poorly understood chronic inflammatory bladder change, in women with recurrent urinary tract infections. MATERIALS AND METHODS: A retrospective, observational cohort of women with recurrent urinary tract infections who underwent cystoscopy (n=138) from 2015 to 2018 were identified using electronic medical records. Cystitis cystica status was abstracted from cystoscopy reports and correlations were identified by logistic regression. Urinary tract infection-free survival time associated with cystitis cystica was evaluated by Cox proportional hazards regression. Exact logistic regression was used to identify factors associated with changes to cystitis cystica lesions on repeat cystoscopy. Biopsies of cystitis cystica lesions were examined by routine histology and immunofluorescence. RESULTS: Fifty-three patients (38%) had cystitis cystica on cystoscopy. Cystitis cystica was associated with postmenopausal status (OR: 5.53, 95% CI: 1.39-37.21), pelvic floor myofascial pain (6.82, 1.78-45.04), having ≥4 urinary tract infections in the past year (2.28, 1.04-5.09), and a shorter time to next urinary tract infection (HR: 1.54, 95% CI: 1.01-2.35). Forty-two patients (82%) demonstrated improvement or resolution of lesions. Ten/11 (91%) biopsied cystitis cystica lesions were tertiary lymphoid tissue with germinal centers and resembled follicular cystitis. CONCLUSIONS: Cystitis cystica lesions were associated with postmenopausal status, pelvic floor myofascial pain, and number of urinary tract infections in the prior year and predicted worse recurrent urinary tract infection outcomes. Cystitis cystica lesions are tertiary lymphoid tissue/follicular cystitis that may improve or resolve over time with treatment. Identifying cystitis cystica in recurrent urinary tract infection patients may be useful in informing future urinary tract infection risk and tailoring appropriate treatment strategies.

Evaluation of the Efficacy of Lactobacillus acidophilus in the Treatment of Cyclophosphamide-induced Hemorrhagic Cystitis in Wistar Rats.

BACKGROUND: Hemorrhagic cystitis is an inflammatory complication that can be caused by the administration of cyclophosphamide, which is widely used as an antineoplastic agent. In the search for new therapeutic alternatives, probiotics can suppress the inflammatory process and, therefore, can be used to prevent this disease. OBJECTIVE: Thus, this study aimed to evaluate the effects of using Lactobacillus acidophilus NCFM in the treatment of cyclophosphamide-induced hemorrhagic cystitis in Wistar rats. METHODS: Lactobacillus acidophilus NCFM (2x108 CFU) was used in the treatment of cyclophosphamide- induced hemorrhagic cystitis (200 mg/kg, intraperitoneal) in 77 female Wistar rats. Rats were distributed into experimental groups (n = 9): control group (GC), zero control group (GCZ), inflammation group (GI), 24-hour acute treatment groups: 24-hour lactobacilli treatment group (GL24H) and mesna group (GM), and 30-day chronic treatment groups: lactobacilli treatment group (GTL) and mesna+lactobacilli group (GM+L). After treatment, animals were euthanized and biological materials were collected for blood count, biochemical analyses, examination of abnormal sediment elements (EAS), and histopathological analysis. RESULTS: GI results showed development of edema, macroscopic alterations, and signs of bleeding in the bladder; in addition, lesions in the urothelium and hemorrhage were also found. GL24H and GM presented intact urothelium, without inflammatory reaction and hematological or biochemical urine alterations. CONCLUSION: Therefore, this study demonstrated that L. acidophilus presented uroprotective effect against the action of cyclophosphamide in both the short and long term.

Effect of intravesical tarantula cubensis extract (Theranekron) on inflammation in an interstitial cystitis rat model.

OBJECTIVES: To reveal the histopathological and immunological outcomes of intravesical treatment with tarantula cubensis extract (TCE) in a rat model of interstitial cystitis. METHODS: A total of 30 female Wistar albino rats were divided into three groups: group 1 (control group), group 2 (disease group), and group 3 (treatment group). The rat model of interstitial cystitis was created by biweekly intraperitoneal administration of cyclophosphamide (CYP). In group 3, TCE (a venom extracted from a brown spider known as tarantula cubensis) was administered intravesically after the model had been created. Urothelial degeneration, necrosis, ulcer, bleeding, edema, inflammation and mast cell count, interleukin-6 (IL-6), tumor necrosis factor-alpha (TNF-alpha), myeloperoxidase (MPO), and hydroxyproline parameters were evaluated. Statistical analysis was performed using one-way analysis of variance, chi-square tests, and Kruskal-Wallis tests. RESULTS: All parameters were found to be lower in the rats in group 1 than in the other groups, and IL-6 and MPO values were found to be higher in group 2 (p < .001). The mean TNF-alpha value was highest in group 2 (p = .078). No difference was found between all groups regarding ulcer (p = .087). Urothelial degeneration, necrosis, edema, inflammation, hemorrhage and fibroblast proliferations, and hydroxyproline values were higher in group 3 (p < .001). CONCLUSIONS: Intravesical TCE instillation produces an anti-inflammatory effect by reducing the levels of inflammatory parameters such as IL-6, TNF-alpha, and MPO in bladder tissue. It also accelerates tissue healing by increasing hydroxyproline and fibroblast proliferation.

Effectiveness of ozonized saline solution in the treatment of Proteus spp. bacterial cystitis.

Bacterial cystitis is a common clinical problem among cats and dogs and is one of the main reasons for the administration of antimicrobials. This can cause serious damage to public and animal health, as this practice facilitates the selection of bacteria that are multidrug-resistant to antibiotics. In this context, it is urgent to understand and validate therapeutic modalities that complement antimicrobial treatment in cystitis cases. Ozone therapy has been proposed by scientists owing to the various mechanisms of action in a range of pathologies, both in human and animal medicine. This paper describes the bactericidal action of two different protocols of bladder irrigation with ozonized saline solution (59 µg/mL) in a paraplegic canine with recurrent bacterial cystitis caused by Proteus spp. In the first protocol, the bladder instillations were applied once a day for three consecutive days while in the second, successive lavages were performed throughout the day until a significant reduction in the presence of bacteria in the urine sediment. In this study, we were able to demonstrate that repeated bladder instillation within 24 hours was the most effective treatment for Proteus compared to a single instillation on successive days.

Early-Onset Asymptomatic Polypoid Cystitis in Two Adolescent Male Beagle Dogs.

This brief communication describes a rare spontaneous background lesion in the lower urinary tract of two male laboratory beagles. Proliferative lesions comprising a constellation of histological features consistent with polypoid cystitis were observed in the bladder of two adolescent dogs from a routine preclinical toxicology study. Both animals were clinically asymptomatic and had only minor alterations in urinalysis parameters. While chronic polypoid cystitis is well-recognized in adult pet dogs, this is the first reported case in purpose-bred laboratory beagles. An awareness of this uncommon background finding is important for toxicological pathologists to distinguish it from potential test article-related findings.

Olmesartan ameliorates cyclophosphamide-induced hemorrhagic cystitis in rats via Nrf2/HO-1 signaling pathway.

Hemorrhagic cystitis (HC) is considered a fatal complication of cyclophosphamide (CP). Down-regulation of Nrf2 and induction of pro-inflammatory mediators are the main pathological factors. Recently, ameliorative potential of the angiotensin II (AII) type-1 (AT1) receptor blocker olmesartan (OLM) on oxidative stress and inflammatory cytokines was reported. The current study aims to investigate the possible protective effect of OLM on CP-induced HC in Wistar rats. The animals were divided into the control group (0.5% W/V carboxymethylcellulose, p.o.); OLM group (20 mg/kg, p.o., for 21 days); CP group (a single dose of 100 mg/kg, i.p.); and the remaining groups that received CP i.p. with oral OLM 5, 10 and 20 mg/kg for 21 days, respectively. The bladder tissue was collected for histopathology, immunohistochemistry, ELISA, Western blot, and oxidative stress assay. The OLM at doses of 10 and 20 mg/kg attenuated increase in TNF-α, IL-6, NF-kB, iNOS, and COX-2 induced by CP. Additionally, it up-regulated the Nrf2/HO-1 pathway, bladder GSH content, and CAT and SOD activities. The data indicated that OLM inhibited ROS-induced NF-kB, which caused inhibition of pro-inflammatory cytokines and activation of the Nrf2/HO-1 pathway. Hence, OLM holds great promise for preventing CP-induced HC.

[Urodynamic and histological evaluation of cyclophosphamide-induced bladder pain syndrome in SD rats].

OBJECTIVE: To establish a model of bladder pain syndrome in SD rats by cyclophosphamide intraperitoneal injection, to evaluate the effectiveness of the model from the urodynamic and histological levels, to lay a zoological foundation for the clinical study of bladder pain syndrome, and to further guide clinical treatment. METHODS: Thirty-two 8-week-old SD rats were randomly divided into 4 groups, including acute test group, acute control group, chronic test group, and chronic control group, with 8 rats in each group. The acute test group received intraperitoneal injection of cyclophosphamide 150 mg/kg immediately after the measurement of urodynamic data on the first day, and urodynamic examination was performed again 2 days later. After that, the rats were sacrificed to obtain bladder tissue. In the chronic test group, after measuring the baseline data of urodynamics on the first day, cyclophosphamide 75 mg/kg was intraperitoneally injected on the first, fourth, and seventh days, and the rats were sacrificed after measuring the urodynamic data again on the eighth day to obtain bladder tissue. The acute control group and the chronic control group were injected with the same amount of normal saline during intraperitoneal injection, and the urodynamic testing time point were consistent with the corresponding test groups. Histopathological changes of the bladder were assessed by HE staining. RESULTS: In each acute and chronic group, there were no intragroup differences in baseline urodynamic levels between the test and control groups. The urodynamic maximum bladder volume was significantly reduced in the acute test group after administration(t=-2.961, P < 0.05), histologically, severe interstitial edema, obvious inflammatory cell infiltration, mucosal edema and submucosal hemorrhage, and partial urothelium were absent could be seen, which were consistent with acute cystitis performance. The urodynamic maximum bladder capacity was significantly reduced in the chronic test group after administration (t=-3.886, P < 0.05), and the bladder compliance was lower than that in the control group, but not significant, the histological manifestations were urothelial exfoliation, interstitial edema, submucosal hemorrhage, infiltration of inflammatory cells such as lymphocytes, and dense vascular distribution. CONCLUSION: In the acute test group, a single intraperitoneal injection of cyclophosphamide could induce acute bladder inflammation in the rats. In the chronic test group, repeated injections of cyclophosphamide could induce histological changes in chronic inflammation of chronic bladder pain syndrome in the rats. But the bladder function was not significantly impaired.

Trimetazidine attenuates cyclophosphamide-induced cystitis by inhibiting TLR4-mediated NFκB signaling in mice.

AIM: Cyclophosphamide (CP)-induced cystitis is a challenging clinical problem involving inflammation and dysfunction of bladder. Trimetazidine (TMZ) is an anti-anginal drug with anti-oxidant and anti-inflammatory properties. We aimed to investigate the protective effects of TMZ in CP-induced cystitis via inhibiting TLR4/NFκB signaling. MAIN METHODS: Balb/c mice were administrated TMZ (10 or 20 mg/kg/day) intraperitoneally (i.p.) for 5 consecutive days before CP. On day 6, cystitis was induced by a single dose of CP (300 mg/kg, i.p.). Mesna (2-mercaptoethane sulfonate sodium; 30 mg/kg, i.p.) was administered 20 min before and at 4 and 8 h after the CP injection. After 24 h of cystitis induction, the bladders were removed for histopathological evaluation, contractility studies, biochemical analysis and western blotting. MTT assay was performed in a cancer cell line (MDA-MB-231) to evaluate the effect of TMZ on the cytotoxicity of CP. KEY FINDINGS: CP-induced severe cystitis was confirmed by histological disturbances and the decrease in carbachol-evoked contractions of detrusor strips, which was partially improved by TMZ (20 mg/kg/day). SOD activity and GSH content were decreased whereas TNF-α and IL-1ß levels were increased in the bladders of CP-treated mice, which were restored by TMZ or mesna. TMZ reduced the CP-induced increase in the protein expressions of caspase-3, TLR4 and phosphorylated-NFκB in bladder tissues. TMZ alone decreased the cell viability and TMZ also enhanced the cytotoxicity of CP. SIGNIFICANCE: Our study provides the first preclinical evidence that TMZ attenuates CP-induced urotoxicity by enhancing anti-oxidant capacity and suppressing inflammation possibly via downregulating TLR4-mediated NFκB signaling while augmenting the cytotoxicity of CP.

Neonatal cystitis leads to alterations in spinal corticotropin releasing factor receptor-type 2 content and function in adult rats following bladder re-inflammation.

Spinal mechanisms associated with visceral hypersensitivity are poorly understood. One model of bladder hypersensitivity with phenotypic features similar to the disorder interstitial cystitis/bladder pain syndrome is the neonatal bladder inflammation (NBI) model. In this model, rat pup bladders are infused with zymosan solutions on post-partum days 14-16 and then rats are retested as adults. Studies of other sites of deep tissue hypersensitivity have suggested a role for corticotropin-releasing factor (CRF) receptors type 1 and 2 (CRFR1 and CRFR2). Using neurochemical measures, pharmacological manipulations and both reflex and neuronal responses to urinary bladder distension as endpoints, the present study probed the role of CRFR2s in bladder hyperalgesia secondary to NBI and acute bladder re-inflammation as an adult (ABI). ELISA measures of the lumbosacral spinal cord demonstrated increased CRFR1s and CRFR2s following pretreatment with both NBI + ABI as well as NBI-related increases in the CRFR2 agonist urocortin 2. Intrathecal CRFR2 antagonists, but not a CRFR1 antagonist, blocked the augmentation of visceromotor responses to distension following pretreatment with both NBI + ABI. Lumbosacral dorsal horn neuronal responses to distension in rats pretreated with NBI + ABI were attenuated by the spinal topical administration of a CRFR2 antagonist. These studies suggest therapeutic value of CRFR2 antagonists in the treatment of painful bladder disorders.

Increased extracellular matrix stiffness accompanies compromised bladder function in a murine model of radiation cystitis.

Radiation cystitis, a long-term bladder defect due to pelvic radiation therapy, results in lower urinary tract symptoms, such as urinary frequency and nocturia, suggestive of compromised bladder compliance. The goal of this study was to identify alterations to the mechanical behavior of the urinary bladder extracellular matrix of a murine model of radiation cystitis, at 3 and 6 months after radiation exposure. The results of this study demonstrated that the extracellular matrix of irradiated bladders was significantly less distensible when compared to age matching controls. These findings coincided with functional bladder changes, including increased number of voids and decreased voided volume. Both mechanical and functional changes were apparent at 3 months post-irradiation and were statistically significant at 6 months, demonstrating the progressive nature of radiation cystitis. Overall, the results of this study indicate that irradiation exposure changes both the mechanical and physiological properties of the bladder. STATEMENT OF SIGNIFICANCE: In humans, radiation cystitis results in lower urinary tract symptoms, such as urinary frequency and nocturia, suggestive of compromised bladder compliance. This pathology can significantly affect recovery and quality of life for cancer survivors. Gaining knowledge about how alterations to the mechanical behavior of the urinary bladder extracellular matrix can affect urinary function will have a significant impact on this population. The results of this study demonstrated that the extracellular matrix of irradiated bladders was significantly less distensible when compared to age matching controls, in a mouse model of radiation cystitis. These findings were accompanied by functional voiding changes, including increased number of voids and decreased voided volume. The results of this study uncovered that irradiation exposure changes the mechanical and physiological properties of the bladder.

Understanding Molecular Mechanisms and Identifying Key Processes in Chronic Radiation Cystitis.

Chronic radiation cystitis (CRC) is a consequence of pelvic radiotherapy and affects 5-10% of patients. The pathology of CRC is without curative treatment and is characterized by incontinence, pelvic pain and hematuria, which severely degrades patients' quality of life. Current management strategies rely primarily on symptomatic measures and have certain limitations. Thanks to a better understanding of the pathophysiology of radiation cystitis, studies targeting key manifestations such as inflammation, neovascularization and cell atrophy have emerged and are promising avenues for future treatment. However, the mechanisms of CRC are still better described in animal models than in human models. Preclinical studies conducted to elucidate the pathophysiology of CRC use distinct models and are most often limited to specific processes, such as fibrosis, vascular damage and inflammation. This review presents a synthesis of experimental studies aimed at improving our understanding of the molecular mechanisms at play and identifying key processes in CRC.

Tumor protein P63 Regulated 1 contributes to inflammation and cell proliferation of cystitis glandularis through regulating the NF-кB/cyclooxygenase-2/prostaglandin E2 axis.

Cystitis glandularis is characterized by chronic inflammation and hyperproliferation of bladder mucosa, and contributes to progression of bladder adenocarcinoma. TPRG1 (Tumor Protein P63 Regulated 1) is related to cellular inflammatory response, and dysregulation of TPRG1 in tumor tissues is associated with tumor early recurrence. The effect of TPRG1 on cystitis glandularis was investigated in this study. Firstly, bladder specimen were isolated from patients with cystitis glandularis and E. coli-induced cystitis rat. Expression of TPRG1 was found to be up-regulated in the bladder specimen. Moreover, adeno-associated virus (AAV)-mediated silence of TPRG1 was delivered into rat, and data from hematoxylin and eosin (H and E) staining showed that injection with AAV-shTPRG1 ameliorated E. coli-induced histological changes in bladder tissues of rats, and suppressed the inflammatory response. Secondly, TPRG1 was also increased in primary cystitis glandularis cells. Knockdown of TPRG1 decreased cell proliferation of primary cystitis glandularis cells, and suppressed the migration. Thirdly, cyclooxygenase-2 (COX-2) was up-regulated in the bladder specimen isolated from patients with cystitis glandularis and E. coli-induced cystitis rat. Injection with AAV-shTPRG1 reduced protein expression of COX-2, p65 and prostaglandin E2 (PGE2) in the bladder specimen. Lastly, interference of COX-2 attenuated TPRG1 over-expression-induced increase of cell proliferation and migration in the primary cystitis glandularis cells. In conclusion, TPRG1 promoted inflammation and cell proliferation of cystitis glandularis through activation of NF-кB/COX2/PGE2 axis.

Repeated Low-Dose Acrolein Triggers Irreversible Lamina Propria Edema in Urinary Bladder, Transient Voiding Behavior and Widening of Eyes to Mechanical Stimuli.

Acrolein is a metabolite of cyclophosphamide (CYP), an alkylating agent used for a wide range of benign and malignant diseases. CYP treatments are known to trigger hemorrhagic cystitis in patients and animals. Significant effort has been made to prevent CYP/acrolein-induced cystitis, while still maintaining its therapeutic benefits. As a result, supplementary therapeutic options to mediate the protective role against CYP/acrolein and lower doses of CYP are currently given to targeted patients, as compared to past treatments. There is still a need to further study the effects of the repeated low-dose CYP/acrolein on the pathophysiology of the urinary bladder. In our study, a one-time treatment of acrolein and repeated low-dose acrolein triggered the thickening of the smooth muscle and lamina propria in the urinary bladder of C57BL/6J mice, respectively. The first dose of acrolein did not trigger voiding dysfunction, but the second dose triggered high-volume low-frequency voiding. Interestingly, our new scoring criteria and concurrent behavioral assessment revealed that mice with repeated low-dose acrolein had a wider opening of eyes in response to mechanical stimuli. Our study suggests that clinical symptoms among patients undergoing prolonged low-dose CYP may differ from previously reported symptoms of CYP-induced hemorrhagic cystitis.