STRESS AND SYMPTOMATOLOGY IN PATIENTS WITH INTERSTITIAL CYSTITIS: A LABORATORY STRESS MODEL

Intravesical nerve growth factor antisense therapy for bladder hypersensitivity induced by psychological stress

This study assessed the relationship between NGF expression in the bladder and bladder hypersensitivity caused by psychological stress using water avoidance stress (WAS) in rats by modulating the NGF expression using intravesical liposome-complexed NGF antisense oligonucleotide (OND) therapy on WAS-induced bladder dysfunction. Female Wistar rats were divided into control and WAS groups, the latter of which received WAS sessions for 10 days with or without the OND pretreatment. Rats underwent cystometry with or without intravesical application of low-dose protamine sulfate (LD-PS), or pain behavior measurements after LD-PS application. After functional evaluations, the bladder was harvested for histology and molecular studies. WAS rats with or without LD-PS showed shortened intercontraction intervals and increased pain behaviors compared to control rats, which was improved by OND-treatment. Histological studies revealed that LD-PS provoked urothelial exfoliation in WAS rats. Compared to controls, protein assay showed increased NGF levels, and RT-PCR showed increases of TRPV1 and TRPA1 and a decrease in Cx43 in WAS rat bladders, which were improved by OND-treatment. WAS caused bladder hypersensitivity, which was improved by NGF antisense OND treatment. NGF upregulation in the bladder may be a therapeutic target for the treatment of psychological stress-induced bladder dysfunction.

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

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

Number of patients with interstitial cystitis/bladder pain syndrome seen before versus during the COVID-19 pandemic at an academic, urban, multisite urogynecology practice

OBJECTIVES

Little is known about the impact of the COVID-19 pandemic on interstitial cystitis/bladder pain syndrome (IC/BPS). We aim to compare the number of newly diagnosed IC/BPS cases and number of patients with flares prior to and during the pandemic.

METHODS

We conducted a retrospective cohort study of women ≥18 years who were diagnosed with or treated for IC/BPS between March 2019 and March 2021 at an academic, urban, multisite urogynecology practice. The primary outcome was the number of IC/BPS cases from March 1, 2019 to February 29, 2020 (pre-pandemic) compared with March 1, 2020 to February 28, 2021 (during pandemic). The secondary outcome was the number of patients with flares during those same two time periods. Demographic and clinical characteristics were compared using nonparametric tests and interrupted time series (ITS) was used to evaluate our outcomes of interest. p-Value <.05 was considered significant.

RESULTS

Fifty-four women (4.87% of new patients) were diagnosed with IC/BPS during the pandemic compared with 40 women pre-pandemic (4.05% of new patients). The median age was 35.0. Seventy-two percent were premenopausal, 75% sexually active, and 31% had anxiety, and there were no significant differences between groups. Although the number of patients newly diagnosed with IC/BPS was higher during the pandemic, the diagnosis rates between time periods were not statistically different. Thirty-five patients experienced flares during the pandemic compared with 49 patients the year prior (p = .43). This difference was also not statistically significant on ITS analysis.

CONCLUSIONS

Although more patients were diagnosed with IC/BPS during versus before the pandemic, the difference in diagnosis rates was not different between these periods.

The effect of the pandemic period on Bladder Pain Syndrome patients under amitriptyline treatment

INTRODUCTION

COVID-19 is a disease that may cause anxiety, depression, and stress. Bladder pain syndrome (BPS) is a disease in which stress and psychological factors might negatively affect its course. In this study, we aimed to examine the possible clinical aggregation of the pandemic period on BPS patients.

MATERIALS AND METHODS

A total of 35 BPS patients diagnosed between 2010 and 2018 were included. All patients were using medical treatment, and the follow-up period was at least 6 months. According to our clinical follow-up protocol, the BPS patients were given the King's Health Questionnaire (KHQ), Beck Anxiety Inventory (BAI), Beck Depression Inventory (BDI), Overactive Bladder Form V8 (OAB-V8), and Visual Analog Score (VAS) in every visit. In the sixth month of the pandemic, the clinical course of the patients was questioned by telephone or video interview, and their treatment continuities were questioned. Information was received about the delays in their follow-up and the difficulties in accessing healthcare opportunities. The same questionnaires were filled out and compared with pre-pandemic scores.

RESULTS

The mean age of the patients included in the study was 50.2 ± 13.32 (min:20, max:74), 11 were males and 24 were females. The mean follow-up periods were 71.8 ± 35.6 months. All questionnaire scores showed an increase compared to the pre-pandemic period. A statistically significant increase was detected during the pandemic in all sub-units of the KHQ. The VAS and OAB-V8 scores of 16 patients who requested hospital admission were significantly higher than before the pandemic. However, there was no statistically significant difference in the increase in VAS and OAB-V8 scores of the 19 patients who refused to come to the hospital.

CONCLUSION

BPS patients have been negatively affected by the emotional effects of the COVID-19 pandemic. Due to the fear, stress, anxiety, and depression, the symptoms of BPS patients exacerbated, and the patients could not receive the necessary support due to a lack of regular follow-ups.

Stress-induced symptom exacerbation: Stress increases voiding frequency, somatic sensitivity, and urinary bladder NGF and BDNF expression in mice with subthreshold cyclophosphamide (CYP)

Symptom exacerbation due to stress is prevalent in many disease states, including functional disorders of the urinary bladder (e.g., overactive bladder (OAB), interstitial cystitis/bladder pain syndrome (IC/BPS)); however, the mechanisms underlying the effects of stress on micturition reflex function are unclear. In this study we designed and evaluated a stress-induced symptom exacerbation (SISE) mouse model that demonstrates increased urinary frequency and somatic (pelvic and hindpaw) sensitivity. Cyclophosphamide (CYP) (35 mg/kg; i.p., every 48 hours for a total of 4 doses) or 7 days of repeated variate stress (RVS) did not alter urinary bladder function or somatic sensitivity; however, both CYP alone and RVS alone significantly (p ≤ 0.01) decreased weight gain and increased serum corticosterone. CYP treatment when combined with RVS for 7 days (CYP+RVS) significantly (p ≤ 0.01) increased serum corticosterone, urinary frequency and somatic sensitivity and decreased weight gain. CYP+RVS exposure in mice significantly (p ≤ 0.01) increased (2.6-fold) voiding frequency as we determined using conscious, open-outlet cystometry. CYP+RVS significantly (p ≤ 0.05) increased baseline, threshold, and peak micturition pressures. We also evaluated the expression of NGF, BDNF, CXC chemokines and IL-6 in urinary bladder in CYP alone, RVS alone and CYP+RVS mouse cohorts. Although all treatments or exposures increased urinary bladder NGF, BDNF, CXC and IL-6 content, CYP+RVS produced the largest increase in all inflammatory mediators examined. These results demonstrated that CYP alone or RVS alone creates a change in the inflammatory environment of the urinary bladder but does not result in a change in bladder function or somatic sensitivity until CYP is combined with RVS (CYP+RVS). The SISE model of CYP+RVS will be useful to develop testable hypotheses addressing underlying mechanisms where psychological stress exacerbates symptoms in functional bladder disorders leading to identification of targets and potential treatments.

The Innovative Approach in Functional Bladder Disorders: The Communication Between Bladder and Brain-Gut Axis

Functional bladder disorders including overactive bladder and interstitial cystitis may induce problems in many other parts of our body such as brain and gut. In fact, diagnosis is often less accurate owing to their complex symptoms. To have correct diagnosis of these diseases, we need to understand the pathophysiology behind overlapped clinical presentation. First, we focused on reviewing literatures that have reported the link between bladder and brain, as the patients with bladder disorders frequently accompanied mood disorders such as depression and anxiety. Second, we reviewed literatures that have described the relationship between bladder and gut. There exist many evidences of patients who suffered from both bladder and intestinal diseases, such as irritable bowel syndrome and inflammatory bowel disease, at the same time. Furthermore, the interaction between brain and gut, well-known as brain-gut axis, might be a key factor that could change the activity of bladder and vice versa. For example, the affective disorders could alter the activity of efferent nerves or autonomic nervous system that modulate the gut itself and its microbiota, which might cause the destruction of homeostasis in bladder eventually. In this way, the communication between bladder and brain-gut axis might affect permeability, inflammation, as well as infectious etiology and dysbiosis in bladder diseases. In this review, we aimed to find an innovative insight of the pathophysiology in the functional bladder disorders, and we could provide a new understanding of the overlapped clinical presentation by elucidating the pathophysiology of functional bladder disorders.

Stress-induced bladder hypersensitivity: Effect of corticotropin releasing factor receptors assessed by spinal neurophysiology and neurochemistry

Corticotropin releasing factor (CRF) receptors have been implicated in stress-induced hyperalgesia. The present study examined the role of CRF receptors Type 1&2 (CRFR1, CRFR2) in stress-induced bladder hyperalgesia in female rats by quantifying changes in receptor and agonist content following chronic (CFS, 7 daily episodes), acute (AFS, single episode) and control (NFS, no episodes) footshock protocols. ELISAs demonstrated that CFS lead to an increase in spinal thoracolumbar and lumbosacral spinal cord CRFR2 content and a decrease in lumbosacral spinal cord CRFR1 content. Content of the endogenous CRFR2 agonist, urocortin 2, was also increased in lumbosacral spinal cord and bladder tissues of CFS-pretreated rats, but urocortin 3 was decreased. Correlative single unit studies of lumbosacral dorsal horn neurons excited by bladder distension, in anesthetized rats that had undergone CFS, AFS or NFS protocols, used a before-after methodology with administration of a CRFR1 antagonist (antalarmin, 24 μg), CRFR2 antagonist (aSVG30, 12 μg) or normal saline topically to the exposed spinal cord following primary characterization. aSVG30 produced a reduction of neuronal responses evoked by bladder distension in CFS-pretreated rats but no statistically significant effects of aSVG30, antalarmin or vehicle were noted in other groups tested with the exception that antalarmin had an inhibitory effect on spontaneous activity in NFS-pretreated rats. The present findings are consistent with previous experiments using reflex responses to bladder distension as endpoints and further support a role for CRFR2-related mechanisms in stress-induced bladder hypersensitivity. This suggests CRFR2 antagonists may have efficacy in the treatment of bladder pain.

Feline Uroepithelial Cell Culture as a Novel Model of Idiopathic Cystitis: Investigations on the Effects of Norepinephrine on Inflammatory Response, Oxidative Stress, and Barrier Function

Feline idiopathic cystitis (FIC) is one of the most common urinary tract disorders in domestic cats. As stress is suggested to play a key role in the pathogenesis of FIC, the effects of norepinephrine (NE) as a stress mediator were investigated on a novel feline primary uroepithelial cell culture, serving as an in vitro model of the disease. The uroepithelial cells gained from the mucosa of the bladder of a euthanized cat were cultured for 6 days and were acutely exposed to NE (10, 100, and 1000 µM) for 1 h. NE increased the metabolic activity of the cultured cells and elevated the extracellular concentrations of the pro-inflammatory mediators interleukin-6 (IL-6) and stromal cell derived factor 1 (SDF-1), confirming that NE can trigger an inflammatory response in the uroepithelium. Cellular protein carbonyl levels were increased by NE exposure, while malondialdehyde and glucose regulated protein 78 concentrations remained unchanged, indicating that NE may provoke the oxidative damage of proteins without inducing lipid peroxidation or endoplasmic reticulum stress. Further, it can be strongly suggested that an acute NE challenge might diminish the barrier function of uroepithelial cells, as reflected by the decreased glycosaminoglycan concentration, claudin-4 protein expression, and reduced TER values of the NE-treated cell cultures. Based on these results, short-term NE exposure mimicking acute stress can provoke an inflammatory response and decrease the barrier integrity of cultured feline uroepithelial cells. Hence, it is highly expected that stress-associated NE release may play an important mediatory role in the pathogenesis of FIC.

Repeated variate stress increased voiding frequency and altered TrpV1 and TrpV4 transcript expression in lower urinary tract (LUT) pathways in female mice

Psychological stress is associated with urinary bladder dysfunction (e.g., increased voiding frequency, urgency and pelvic pain); however, the mechanisms underlying the effects of stress on urinary bladder function are unknown. Transient receptor potential (TRP) channels (vanilloid family) may be potential targets for intervention due to their distribution in the LUT and role in pain. Here, we examine a model of repeated variate stress (RVS) of 2 week (wk) or 4 wk duration in female mice and its effects on bladder function, anxiety-like behavior, and TRPV transcript expression in urinary bladder and lumbosacral spinal cord and associated dorsal root ganglia (DRG). Using continuous infusion, open-outlet cystometry in conscious mice, RVS significantly (p ≤ 0.05) decreased infused volume and intermicturition interval. Bladder pressures (threshold, average, minimum, and maximum pressures) were unchanged with RVS. Quantitative PCR demonstrated significant (p ≤ 0.05) changes in TrpV1 and TrpV4 mRNA expression between control and RVS cohorts in the urothelium, lumbosacral spinal cord, and DRG. Future directions will examine the contribution of TRP channels on bladder function, somatic sensation and anxiety-like behavior following RVS.

Silodosin Improves Pain and Urinary Frequency in Bladder Pain Syndrome/Interstitial Cystitis Patients

Purpose: Bladder Pain Syndrome/Interstitial Cystitis (BPS/IC) is a bladder-related chronic inflammatory disease. Data indicate that stress enhances the excitability of bladder nociceptors through the stimulation of alpha1A-adrenoceptors. Stress is known to play a crucial role in BPS/IC patients. We aimed to assess the efficacy and safety of daily silodosin in refractory BPS/IC female patients and its correlation with stress coping. Materials and Methods: An open-label trial was conducted with 20 refractory BPS/IC patients. Evaluations occurred at baseline and the 8th and 12th weeks. Primary endpoint was bladder pain evaluated by visual analogue scale (VAS). Secondary endpoints included daily frequency, nocturia and maximum voided volume obtained from a 3-day bladder diary, the O’Leary−Sant Symptom Score, and two questions accessing stress coping. Patients initiated daily doses of 8 mg silodosin, which could be titrated to 16 mg. Median values with percentiles 25 and 75 (25; 75) were used. Wilcoxon signed-rank test was used for comparisons. A minimally important difference of 3 points for pain was established to define clinically relevant improvement. Results: Median age was 56 years. Median pain score decreased from 8.00 (6.00; 8.00) at baseline to 4.00 (2.00; 5.50) (p < 0.001), meaning that the primary endpoint was reached. Total urinary frequency decreased from 14.00 (13.00; 21.00) to 9.00 (7.50; 11.00) (p < 0.05), and all the other secondary endpoints also showed a statistically significant improvement. Eleven patients improved by ≥3 pain points in VAS, meaning that 65% of patients that ended the study protocol achieved clinical significant improvement or, in the full analysis set, that 55% of the 20 initial patients improved significantly. Fourteen (82%) decreased by ≥2 micturitions/day. Overall, the cohort’s stress coping was low. Conclusions: Silodosin can be an effective and well-tolerated treatment for refractory BPS/IC female patients.

Neonatal cystitis alters mechanisms of stress-induced visceral hypersensitivity in rats

In rodent models, conditioning with acute footshock (AFS) has been demonstrated to produce bladder hypersensitivity which is more robust when rats, tested as adults, had also been pretreated with neonatal bladder inflammation (NBI). The spinal neurochemical mechanisms of pro-nociceptive processes in rats pretreated with NBI are not fully known and so the present study administered intrathecal (IT) opioid (naloxone) and NMDA receptor (MK-801) antagonists to determine whether these receptors' actions had been altered by NBI. Female Sprague-Dawley rat pups were intravesically pretreated on postnatal days P14-P16 with a 1% zymosan solution or with control procedures and then raised to adulthood (12-15 weeks of age). Bladder hypersensitivity was induced through use of an AFS paradigm. Visceromotor responses (VMRs; abdominal muscle contractions) to graded, air pressure-controlled urinary bladder distension were used as nociceptive endpoints. Immediately following AFS pretreatments, rats were anesthetized and surgically prepared. Pharmacological antagonists were administered via an IT catheter onto the lumbosacral spinal cord and VMRs determined 15 min later. Administration of IT naloxone hydrochloride (10 μg) to rats which had been pretreated only with AFS resulted in VMRs that were more robust than VMRs in similarly pretreated rats that received IT normal saline. In contrast, IT naloxone had no significant effect on rats that had been pretreated with both NBI&AFS, although MK-801 was inhibitory. These effects of IT naloxone suggest the presence of inhibitory influences in normal rats that are absent in rats pretreated with NBI. Absence of inhibitory influences produced by AFS was also demonstrated in rats pretreated with NBI&AFS using measures of thermal paw withdrawal latency (PWL): rats pretreated with only AFS had longer PWLs than rats pretreated with both NBI&AFS. Together, a reduction in anti-nociceptive mechanisms coupled with pro-nociceptive NMDA-linked mechanisms results in more robust nociceptive responses to distension in rats which had experienced NBI.

Spinal neurochemical mechanisms of acute stress-induced visceral hypersensitivity in healthy rats

Psychological stress has been demonstrated to increase reports of pain in humans with pelvic pain of urologic origin. In rodent models, conditioning with acute footshock (AFS) has been demonstrated to increase measures of stress/anxiety as well as bladder hypersensitivity. The spinal neurochemical mechanisms of this pro-nociceptive process are unknown and so the present study administered antagonists for multiple receptors that have been associated with facilitatory mechanisms into the spinal intrathecal space. Bladder hypersensitivity was induced through use of an AFS paradigm in which female Sprague-Dawley rats received a 15-min intermittent shock treatment. Visceromotor responses (VMRs; abdominal muscle contractions) to air pressure-controlled urinary bladder distension (UBD) were used as nociceptive endpoints. Immediately following AFS treatments, rats were anesthetized (inhaled isoflurane, IP urethane) and surgically prepared. Pharmacological antagonists were administered via an intrathecal (IT) catheter onto the lumbosacral spinal cord and VMRs to graded UBD determined 15 min later. Administration of IT naloxone hydrochloride (10 μg) and IT phentolamine hydrochloride (10 μg) resulted in VMRs that were more robust than VMRs in rats that received AFS and IT normal saline whereas there was no significant effect of these drugs on VMRs in rats which underwent non-footshock procedures. In contrast, a low dose of the NMDA-receptor antagonist, MK-801 (30 μg), significantly reduced VMRs in rats made hypersensitive to UBD by AFS, but had no significant effect on rats that underwent non-footshock procedures. This study suggests that pro-nociceptive effects of AFS in otherwise healthy rats involve a spinal NMDA-linked mechanism. The effects of IT naloxone and IT phentolamine suggest the presence of inhibitory influences that are opioidergic and/or alpha-adrenergic and that are masked by the pro-nociceptive mechanisms. Other agents with no statistically significant effect on VMRs include methysergide (30 μg), ondansetron (10 μg), mecamylamine (50 μg), antalarmin (24 μg), aSVG30 (12 μg), and SSR149415 (50 μg).

Psychological/mental stress-induced effects on urinary function: Possible brain molecules related to psychological/mental stress-induced effects on urinary function

Exposure to psychological/mental stress can affect urinary function, and lead to and exacerbate lower urinary tract dysfunctions. There is increasing evidence showing stress-induced changes not only at phenomenological levels in micturition, but also at multiple levels, lower urinary tract tissues, and peripheral and central nervous systems. The brain plays crucial roles in the regulation of the body's responses to stress; however, it is still unclear how the brain integrates stress-related information to induce changes at these multiple levels, thereby affecting urinary function and lower urinary tract dysfunctions. In this review, we introduce recent urological studies investigating the effects of stress exposure on urinary function and lower urinary tract dysfunctions, and our recent studies exploring "pro-micturition" and "anti-micturition" brain molecules related to stress responses. Based on evidence from these studies, we discuss the future directions of central neurourological research investigating how stress exposure-induced changes at peripheral and central levels affect urinary function and lower urinary tract dysfunctions. Brain molecules that we explored might be entry points into dissecting the stress-mediated process for modulating micturition.

Chronic psychological stress and lower urinary tract symptoms

It is well established that lower urinary tract symptoms (LUTS), particularly urinary urgency and incontinence, cause stress and anxiety for patients. However, there is mounting evidence that the relationship between these two factors is bidirectional and that chronic psychological stress itself can result in the development of symptoms such as urinary frequency, urgency, incontinence, and pelvic pain. This review considers the evidence that such a relationship exists and reviews the literature from clinical and animal studies to identify some of the mechanisms that might be involved. Inflammatory responses induced by chronic stress appear to offer the strongest link to bladder dysfunction. There is overwhelming evidence, both in patients and animal models, for a release of pro-inflammatory cytokines and chemokines during periods of chronic stress. Furthermore, cytokines have been shown to cause bladder dysfunction and pain via actions in the central nervous system and locally in the bladder. In the brain and spinal cord, pro-inflammatory cytokines influence the regulation of micturition pathways by corticotropin-releasing factor (CRF) and its receptors, while peripherally cytokines affect bladder function, directly causing detrusor hypertrophy and afferent nerve hypersensitivity. There is little information on which treatments may have most benefit for stressed/anxious patients with LUTS, but animal studies suggest traditional drugs for overactive bladder (solifenacin, mirabegron) are more effective on LUTS than anxiolytic drugs (fluoxetine, imipramine). The preliminary preclinical data for CRF receptor antagonists is not consistent. A clearer understanding of the mechanisms involved in stress-induced LUTS should provide a basis for improved treatment of this condition.

Adversity and Depression: The Moderating Role of Stress Reactivity among High and Low Risk Youth

Adverse life events have been causally linked to depression among youth at high risk for depression. But given that not all high-risk youth develop depression following adversity, individual differences in various processes, including physiological reactivity to stress, are likely to be at play. This longitudinal prospective study tested the hypothesis that, among high-risk youth exposed to adversities, extent of physiological reactivity to laboratory stress (indexed as respiratory sinus arrhythmia; RSA) would predict subsequent depressive symptoms. Subjects were youth at high (n = 80) and low (n = 74) familial risk for depression. At Time 1 (T1), RSA was assessed during a cognitive stress task. At Time 2 (T2) about 2 years later, parents reported on adversities experienced by their offspring during the interim. At T1 and T2, youth received a diagnostic evaluation, which included assessment of their depressive symptoms. The three-way interaction of group-X-adversities-X-RSA predicted T2 depressive symptoms (controlling for T1 depressive symptoms). This interaction was mostly driven by the moderating effect of RSA among high-risk youth, such that adversities predicted higher depressive symptoms for those who displayed greater RSA reactivity to stress. Among low-risk youth, an inverse marginal moderating effect of RSA was found, such that adversities tended to predict depressive symptoms for those who displayed blunted RSA reactivity to stress. Thus, high physiological stress reactivity appears to be an additional risk factor for depressive symptoms only among youth at elevated risk for such outcomes, and should be taken into consideration in efforts to prevent depression in these populations.

Intrabladder PAC1 Receptor Antagonist, PACAP(6-38), Reduces Urinary Bladder Frequency and Pelvic Sensitivity in Mice Exposed to Repeated Variate Stress (RVS)

Stress causes symptom exacerbation in functional disorders of the urinary bladder. However, the potential mediators and underlying mechanisms of stress effects on micturition reflex function are unknown. We have characterized PACAP (Adcyap1) and PAC1 receptor (Adcyap1r1) signaling in stress-induced urinary bladder dysfunction in mice. We determined PACAP and PAC1 transcripts and protein expressions in the urinary bladder and lumbosacral dorsal root ganglia (DRG) and spinal cord in repeated variate stress (RVS) or control mouse (handling only) groups. RVS in mice significantly (p ≤ 0.01) increased serum corticosterone and urinary bladder NGF content and decreased weight gain. PACAP and PAC1 mRNA and protein were differentially regulated in lower urinary tract tissues with changes observed in lumbosacral DRG and spinal cord but not in urinary bladder. RVS exposure in mice significantly (p ≤ 0.01) increased (2.5-fold) voiding frequency as determined using conscious cystometry. Intrabladder administration of the PAC1 receptor antagonist, PACAP(6-38) (300 nM), significantly (p ≤ 0.01) increased infused volume (1.5-2.7-fold) to elicit a micturition event and increased the intercontraction interval (i.e., decreased voiding frequency) in mice exposed to RVS and in control mice, but changes were smaller in magnitude in control mice. We also evaluated the effect of PAC1 blockade at the level of the urinary bladder on pelvic sensitivity in RVS or control mouse groups using von Frey filament testing. Intrabladder administration of PACAP(6-38) (300 nM) significantly (p ≤ 0.01) reduced pelvic sensitivity following RVS. PACAP/receptor signaling in the CNS and PNS contributes to increased voiding frequency and pelvic sensitivity following RVS and may represent a potential target for therapeutic intervention.

Ceftriaxone inhibits stress-induced bladder hyperalgesia and alters cerebral micturition and nociceptive circuits in the rat: A multidisciplinary approach to the study of urologic chronic pelvic pain syndrome research network study

AIMS

Emotional stress plays a role in the exacerbation and development of interstitial cystitis/bladder pain syndrome (IC/BPS). Given the significant overlap of brain circuits involved in stress, anxiety, and micturition, and the documented role of glutamate in their regulation, we examined the effects of an increase in glutamate transport on central amplification of stress-induced bladder hyperalgesia, a core feature of IC/BPS.

METHODS

Wistar-Kyoto rats were exposed to water avoidance stress (WAS, 1 hour/day x 10 days) or sham stress, with subgroups receiving daily administration of ceftriaxone (CTX), an activator of glutamate transport. Thereafter, cystometrograms were obtained during bladder infusion with visceromotor responses (VMR) recorded simultaneously. Cerebral blood flow (CBF) mapping was performed by intravenous injection of [¹⁴ C]-iodoantipyrine during passive bladder distension. Regional CBF was quantified in autoradiographs of brain slices and analyzed in three dimensional reconstructed brains with statistical parametric mapping.

RESULTS

WAS elicited visceral hypersensitivity during bladder filling as demonstrated by a decreased pressure threshold and VMR threshold triggering the voiding phase. Brain maps revealed stress effects in regions noted to be responsive to bladder filling. CTX diminished visceral hypersensitivity and attenuated many stress-related cerebral activations within the supraspinal micturition circuit and in overlapping limbic and nociceptive regions, including the posterior midline cortex (posterior cingulate/anterior retrosplenium), somatosensory cortex, and anterior thalamus.

CONCLUSIONS

CTX diminished bladder hyspersensitivity and attenuated regions of the brain that contribute to nociceptive and micturition circuits, show stress effects, and have been reported to demonstrated altered functionality in patients with IC/BPS. Glutamatergic pharmacologic strategies modulating stress-related bladder dysfunction may be a novel approach to the treatment of IC/BPS.

Quantitative assessment of nonpelvic pressure pain sensitivity in urologic chronic pelvic pain syndrome: a MAPP Research Network study

Experimental pain sensitivity was assessed in individuals with urologic chronic pelvic pain syndrome (UCPPS) as part of the Multidisciplinary Approach to the Study of Chronic Pelvic Pain (MAPP) Research Network. A series of computer-controlled pressure stimuli were delivered to the thumbnail bed, an asymptomatic site distant from the area of UCPPS pain that is considered to be indicative of overall body pain threshold. Stimuli were rated according to a standardized magnitude estimation protocol. Pain sensitivity in participants with UCPPS was compared with healthy controls and a mixed pain group composed of individuals with other chronic overlapping pain conditions, including fibromyalgia, chronic fatigue, and irritable bowel syndromes. Data from 6 participating MAPP testing sites were pooled for analysis. Participants with UCPPS (n = 153) exhibited an intermediate pain sensitivity phenotype: they were less sensitive relative to the mixed pain group (n = 35) but significantly more sensitive than healthy controls (n = 100). Increased pain sensitivity in patients with UCPPS was associated with both higher levels of clinical pain severity and more painful body areas outside the pelvic region. Exploratory analyses in participants with UCPPS revealed that pain sensitivity increased during periods of urologic symptom flare and that less pressure pain sensitivity at baseline was associated with a greater likelihood of subsequent genitourinary pain improvement 1 year later. The finding that individuals with UCPPS demonstrate nonpelvic pain hypersensitivity that is related to clinical symptoms suggests that central nervous system mechanisms of pain amplification contribute to UCPPS.

Application of Adult and Pluripotent Stem Cells in Interstitial Cystitis/Bladder Pain Syndrome Therapy: Methods and Perspectives

Interstitial cystitis/bladder pain syndrome (IC/BPS) is a multifactorial, chronic disease without definite etiology characterized by bladder-related pelvic pain. IC/BPS is associated with pain that negatively affects the quality of life. There are various therapeutic approaches against IC/BPS. However, no efficient therapeutic agent against IC/BPS has been discovered yet. Urothelium dysfunction is one of the key factors of IC/BPS-related pathogenicity. Stem cells, including adult stem cells (ASCs) and pluripotent stem cells (PSCs), such as embryonic stem cells (ESCs) and induced PSCs (iPSCs), possess the abilities of self-renewal, proliferation, and differentiation into various cell types, including urothelial and other bladder cells. Therefore, stem cells are considered robust candidates for bladder regeneration. This review provides a brief overview of the etiology, pathophysiology, diagnosis, and treatment of IC/BPS as well as a summary of ASCs and PSCs. The potential of ASCs and PSCs in bladder regeneration via differentiation into bladder cells or direct transplantation into the bladder and the possible applications in IC/BPS therapy are described in detail. A better understanding of current studies on stem cells and bladder regeneration will allow further improvement in the approaches of stem cell applications for highly efficient IC/BPS therapy.

[Central regulation mechanisms for stress-induced frequent urination]

Psychological stress can induce not only frequent urination but also exacerbation of bladder dysfunctions. However, the brain pathophysiological mechanisms underlying stress-induced effects on the micturition reflex are still unknown. Bombesin (BB)-related peptides and BB receptors in the brain have been reported to mediate and integrate stress responses. We have found that centrally administered BB induced frequent urination in rats through brain BB₁ and BB₂ receptors, serotoninergic nervous system/5-HT₇ receptors and corticotropin-releasing factor (CRF) type1 (CRF₁) receptors. Interestingly, the BB-induced frequent urination was independent of the BB-induced activation of the sympatho-adrenomedullary outflow, a representative response to stress. Because the outflow is well known to regulate micturition, the finding was very surprising. These findings indicate that brain BB₁, BB₂, 5-HT₇ and CRF₁ receptors could be new therapeutic targets for bladder dysfunction exacerbated by stress exposure.

Stress-induced autonomic dysregulation of mitochondrial function in the rat urothelium

AIM

Chronic stress exacerbates the symptoms of most pain disorders including interstitial cystitis/bladder pain syndrome (IC/BPS). Abnormalities in urothelial cells (UTC) occur in this debilitating bladder condition. The sequence of events that might link stress (presumably through increased sympathetic nervous system-SNS activity) to urothelial dysfunction are unknown. Since autonomic dysregulation, mitochondrial dysfunction, and oxidative stress all occur in chronic pain, we investigated whether chronic psychological stress initiated a cascade linking these three dysfunctions.

METHODS

Adult female Wistar Kyoto rats were exposed to 10 days of water avoidance stress (WAS). Bladders were then harvested for Western blot and single cell imaging in UTC cultures.

RESULTS

UTC from WAS rats exhibited depolarized mitochondria membrane potential (Ψm ∼30% more depolarized compared to control), activated AMPK and altered UT mitochondria bioenergetics. Expression of the fusion protein mitofusion-2 (MFN-2) was upregulated in the mucosa, suggesting mitochondrial structural changes consistent with altered cellular metabolism. Intracellular calcium levels were elevated in cultured WAS UTC, consistent with impaired cellular function. Stimulation of cultured UTC with alpha-adrenergic (α-AR) receptor agonists increased reactive oxidative species (ROS) production, suggesting a direct action of SNS activity on UTC. Treatment of rats with guanethidine to block SNS activity prevented most of WAS-induced changes.

CONCLUSIONS

Chronic stress results in persistent sympathetically mediated effects that alter UTC mitochondrial function. This may impact the urothelial barrier and signaling, which contributes to bladder dysfunction and pain. This is the first demonstration, to our knowledge, of a potential autonomic mechanism directly linking stress to mitochondrial dysfunction.

Management of Symptom Flares and Patient-reported Flare Triggers in Interstitial Cystitis/Bladder Pain Syndrome (IC/BPS)-Findings From One Site of the MAPP Research Network

OBJECTIVE

To document patient-reported interstitial cystitis/bladder pain syndrome (IC/BPS) flare management strategies and triggers.

MATERIALS AND METHODS

Twenty-four male and 29 female participants enrolled at the Washington University site of the MAPP Research Network completed a questionnaire on strategies they utilized to manage flares and factors they believed triggered their flares (eg, specific food items, physical activities, sexual activities, infections, and stress). Participants were also asked about the diurnal timing of their flares.

RESULTS

A total of 96.2% of participants reported having ever experienced a symptom flare. Participants treated or managed their flares using a wide variety of strategies, ranging from common strategies, such as drinking additional water or fluid (74.5%), to less common strategies, such as acupuncture/acupressure (5.9% of participants). Participants also reported a wide range of perceived flare triggers, including previously reported factors (citrus fruits, tomatoes, spicy food, alcoholic and caffeinated beverages, driving/sitting in forms of transportation, urinary tract infections, stress, and tight clothing), as well as some less common, previously undocumented factors (eg, certain foods, nongenitourinary infections, wearing high-heeled shoes/boots or perfume, hair dye, and toothpaste). In general, female participants and those with somatic sensory hypersensitivity reported greater numbers of therapies and triggers. Finally, flares were reported most commonly in the afternoon or evening.

CONCLUSION

IC/BPS participants reported diverse flare management strategies and numerous perceived triggers. These findings, together with those from the small body of literature to date, provide a wide array of candidates and hypotheses for future global and tailored flare management and prevention interventions.

Neonatal bladder inflammation alters the role of the central amygdala in hypersensitivity produced by Acute Footshock stress in adult female rats

There is increasing evidence that chronic pain may be associated with events that occur during critical periods of development. Recent studies have identified behavioral, spinal neurophysiological and spinal/peripheral neurochemical differences in rats that have experienced neonatal bladder inflammation (NBI): a putative model of the chronically painful bladder disorder, interstitial cystitis. Stress has been shown to exacerbate symptoms of interstitial cystitis and produces bladder hypersensitivity in animal models. We recently reported that Acute Footshock-induced bladder hypersensitivity was eliminated in otherwise normal rats by prior bilateral lesions of the central nucleus of the amygdala. Since the spinal and peripheral nervous systems of NBI-treated rats are known to differ from normal rats, the present experiments sought to determine whether a supraspinal nervous system structure, the central amygdala, is still necessary for the induction of Acute Footshock-induced hypersensitivity. The effect of bilateral amygdala electrolytic lesions on Acute Footshock-induced bladder hypersensitivity in adult female rats was tested in Control rats which underwent a control protocol as neonates and in experimental rats which experienced NBI. Consistent with our previous report, in Control rats, Acute Footshock-induced bladder hypersensitivity was eliminated by bilateral Amygdala Lesions. In contrast, Acute Footshock-induced bladder hypersensitivity in NBI-treated rats was unaffected by bilateral Amygdala Lesions. These findings provide evidence that NBI results in the recruitment of substrates of bladder hypersensitivity that may differ from those of normal rats. This, in turn, suggests that unique therapeutics may be needed for painful bladder disorders like interstitial cystitis.

A Case-Crossover Study of Urological Chronic Pelvic Pain Syndrome Flare Triggers in the MAPP Research Network

PURPOSE

Although many factors have been proposed to trigger symptom exacerbations (flares) in patients with interstitial cystitis/bladder pain syndrome and chronic prostatitis/chronic pelvic pain syndrome, few studies have investigated these factors empirically. Therefore, we embedded a case-crossover study in the Multidisciplinary Approach to the Study of Chronic Pelvic Pain longitudinal study to evaluate a range of patient reported triggers.

MATERIALS AND METHODS

We assessed exposure to proposed triggers, including diet, physical activities, sedentary behaviors, stress, sexual activities, infection-like symptoms and allergies, by questionnaire a maximum of 3 times when participants reported flares and at 3 randomly selected times. We compared participant preflare to nonflare exposures by conditional logistic regression.

RESULTS

In our full analytical sample of 292 participants only 2 factors, including recent sexual activity (OR 1.44, 95% CI 1.06-1.96) and urinary tract infection symptoms (OR 3.39, 95% CI 2.02-5.68), which may overlap with those of flares, were associated with flare onset. On subanalyses restricted to flares with specific suspected triggers additional positive associations were observed for some factors such as certain dietary factors, abdominal muscle exercises, and vaginal infection-like symptoms and fever, but not for other factors (eg stress).

CONCLUSIONS

Except for sexual activity our findings suggest that patient reported triggers may be individual or group specific, or they may not contribute to flares. These findings suggest caution in following rigid, global flare prevention strategies and support additional research to develop evidence-based strategies.

PACAP/Receptor System in Urinary Bladder Dysfunction and Pelvic Pain Following Urinary Bladder Inflammation or Stress

Complex organization of CNS and PNS pathways is necessary for the coordinated and reciprocal functions of the urinary bladder, urethra and urethral sphincters. Injury, inflammation, psychogenic stress or diseases that affect these nerve pathways and target organs can produce lower urinary tract (LUT) dysfunction. Numerous neuropeptide/receptor systems are expressed in the neural pathways of the LUT and non-neural components of the LUT (e.g., urothelium) also express peptides. One such neuropeptide receptor system, pituitary adenylate cyclase-activating polypeptide (PACAP; Adcyap1) and its cognate receptor, PAC1 (Adcyap1r1), have tissue-specific distributions in the LUT. Mice with a genetic deletion of PACAP exhibit bladder dysfunction and altered somatic sensation. PACAP and associated receptors are expressed in the LUT and exhibit neuroplastic changes with neural injury, inflammation, and diseases of the LUT as well as psychogenic stress. Blockade of the PACAP/PAC1 receptor system reduces voiding frequency in preclinical animal models and transgenic mouse models that mirror some clinical symptoms of bladder dysfunction. A change in the balance of the expression and resulting function of the PACAP/receptor system in CNS and PNS bladder reflex pathways may underlie LUT dysfunction including symptoms of urinary urgency, increased voiding frequency, and visceral pain. The PACAP/receptor system in micturition pathways may represent a potential target for therapeutic intervention to reduce LUT dysfunction.

Effects of water avoidance stress on peripheral and central responses during bladder filling in the rat: A multidisciplinary approach to the study of urologic chronic pelvic pain syndrome (MAPP) research network study

Stress plays a role in the exacerbation and possibly the development of functional lower urinary tract disorders. Chronic water avoidance stress (WAS) in rodents is a model with high construct and face validity to bladder hypersensitive syndromes, such as interstitial cystitis/bladder pain syndrome (IC/BPS), characterized by urinary frequency and bladder hyperalgesia and heightened stress responsiveness. Given the overlap of the brain circuits involved in stress, anxiety, and micturition, we evaluated the effects chronic stress has on bladder function, as well as its effects on regional brain activation during bladder filling. Female Wistar-Kyoto rats were exposed to WAS (10 days) or sham paradigms. One day thereafter, cystometrograms were obtained during titrated bladder dilation, with visceromotor responses (VMR) recorded simultaneously. Cerebral perfusion was assessed during passive bladder distension (20-cmH₂O) following intravenous administration of [¹⁴C]-iodoantipyrine. Regional cerebral blood flow was quantified by autoradiography and analyzed in 3-dimensionally reconstructed brains with statistical parametric mapping. WAS animals compared to controls demonstrated a decreased pressure threshold and visceromotor threshold triggering the voiding phase. At 20-cmH₂O, VMR was significantly greater in WAS animals compared to controls. WAS animals showed greater activation in cortical regions of the central micturition circuit, including the posterior cingulate, anterior retrosplenial, somatosensory, posterior insula, orbital, and anterior secondary (“supplementary”) motor cortices, as well as in the thalamus, anterior hypothalamus, parabrachial and Barrington nuclei, and striatum. Seed analysis showed increased functional connectivity of WAS compared to control animals of the posterior cingulate cortex to the pontine parabrachial nucleus; of the Barrington nucleus to the anterior dorsal midline and ventrobasilar thalamus and somatosensory and retrosplenial cortices; and of the posterior insula to anterior secondary motor cortex. Our findings show a visceral hypersensitivity during bladder filling in WAS animals, as well as increased engagement of portions of the micturition circuit responsive to urgency, viscerosensory perception and its relay to motor regions coordinating imminent bladder contraction. Results are consistent with recent findings in patients with interstitial cystitis, suggesting that WAS may serve as an animal model to elucidate the mechanisms leading to viscerosensitive brain phenotypes in humans with IC/BPS.

Lesions of the central amygdala and ventromedial medulla reduce bladder hypersensitivity produced by acute but not chronic foot shock

Both acute and chronic stress has been shown to exacerbate symptoms of chronic visceral pain conditions such as interstitial cystitis. Studies using animal models support these findings in that both acute and chronic exposure to foot shock-induced stress (FS) augment nociceptive reflex responses to urinary bladder distension (UBD). Only a few studies have examined the neural substrates mediating these phenomena and it is not clear whether acute and chronic stress engage the same or different substrates to produce bladder hypersensitivity. The present studies examined the role of two important central nervous system structures - the amygdala (AMG) and the ventromedial medulla (VMM) - in mediating/modulating hypersensitivity evoked by acute versus chronic FS using responses to graded UBD in adult, female Sprague-Dawley rats. Bladder hypersensitivity produced by acute FS was significantly reduced by either bilateral central AMG or VMM lesions using measures generated by graded UBD, but these lesions had no significant effects using the same measures on bladder hyperalgesia produced by chronic FS. Our findings provide evidence that neural substrates underlying bladder hypersensitivity produced by chronic stress differ from those produced by acute stress. These findings suggest that while the AMG and VMM participate in pain processing during periods of limited exposure to stress, prolonged stress may recruit a new set of neural substrates not initially activated by acute exposure to stress.

Brain serotoninergic nervous system is involved in bombesin-induced frequent urination through brain 5-HT7 receptors in rats

BACKGROUND AND PURPOSE

Psychological stress exacerbates symptoms of urinary bladder dysfunction; however, the underlying brain mechanisms are unclear. We have demonstrated that centrally administered bombesin, a stress-related neuropeptide, facilitates the rat micturition reflex. Brain bombesin-like peptides modulate the serotoninergic nervous system activity under stress conditions; therefore, we examined whether brain 5-HT is involved in the bombesin-induced increased frequency of urination in urethane-anaesthetised male Sprague-Dawley rats.

EXPERIMENTAL APPROACH

Evaluation of intercontraction intervals (ICI) and maximal voiding pressure (MVP) during cystometrograms were started 1 h before i.c.v. administration of bombesin or i.c.v. pretreatment with the 5-HT receptor antagonists.

KEY RESULTS

Bombesin (0.03 nmol per animal, i.c.v.) significantly reduced ICI without affecting MVP. The bombesin-induced response was significantly suppressed by acute depletion of brain 5-HT, which was induced by pretreatment with p-chlorophenylalanine, a 5-HT synthesis inhibitor. Bombesin at a lower dose (0.01 nmol per animal, i.c.v.) showed no significant effect on ICI, while it significantly reduced ICI in the presence of WAY-100635 (5-HT_1A receptor antagonist, 0.1 or 0.3 μg per animal, i.c.v.), which can block the negative feedback control of 5-HT release. Bombesin (0.03 nmol per animal)-induced ICI reduction was significantly attenuated by SB269970 (5-HT₇ receptor antagonist, 0.1 or 0.3 μg per animal, i.c.v.) but not by ritanserin (5-HT₂ receptor antagonist, 0.3 or 1 μg per animal, i.c.v.).

CONCLUSIONS AND IMPLICATIONS

The brain serotoninergic nervous system is involved in the facilitation of the rat micturition reflex induced by bombesin-like peptides at least in part through brain 5-HT₇ receptors.

Identification of novel non-invasive biomarkers of urinary chronic pelvic pain syndrome: findings from the Multidisciplinary Approach to the Study of Chronic Pelvic Pain (MAPP) Research Network

OBJECTIVE

To examine a series of candidate markers for urological chronic pelvic pain syndrome (UCPPS), selected based on their proposed involvement in underlying biological processes so as to provide new insights into pathophysiology and suggest targets for expanded clinical and mechanistic studies.

METHODS

Baseline urine samples from Multidisciplinary Approach to the Study of Chronic Pelvic Pain (MAPP) Research Network study participants with UCPPS (n = 259), positive controls (PCs; chronic pain without pelvic pain, n = 107) and healthy controls (HCs, n = 125) were analysed for the presence of proteins that are suggested in the literature to be associated with UCPPS. Matrix metalloproteinase (MMP)-2, MMP-9, MMP-9/neutrophil gelatinase-associated lipocalin (NGAL) complex (also known as Lipocalin 2), vascular endothelial growth factor (VEGF), VEGF receptor 1 (VEGF-R1) and NGAL were assayed and quantitated using mono-specific enzyme-linked immunosorbent assays for each protein. Log-transformed concentration (pg/mL or ng/mL) and concentration normalized to total protein (pg/μg) values were compared among the UCPPS, PC and HC groups within sex using the Student's t-test, with P values adjusted for multiple comparisons. Multivariable logistic regression and receiver-operating characteristic curves assessed the utility of the biomarkers in distinguishing participants with UCPPS and control participants. Associations of protein with symptom severity were assessed by linear regression.

RESULTS

Significantly higher normalized concentrations (pg/μg) of VEGF, VEGF-R1 and MMP-9 in men and VEGF concentration (pg/mL) in women were associated with UCPPS vs HC. These proteins provided only marginal discrimination between UCPPS participants and HCs. In men with UCCPS, pain severity was significantly positively associated with concentrations of MMP-9 and MMP-9/NGAL complex, and urinary severity was significantly positively associated with MMP-9, MMP-9/NGAL complex and VEGF-R1. In women with UCPPS, pain and urinary symptom severity were associated with increased normalized concentrations of MMP-9/NGAL complex, while pain severity alone was associated with increased normalized concentrations of VEGF, and urinary severity alone was associated with increased normalized concentrations of MMP-2. Pain severity in women with UCPPS was significantly positively associated with concentrations of all biomarkers except NGAL, and urinary severity with all concentrations except VEGF-R1.

CONCLUSION

Altered levels of MMP-9, MMP-9/NGAL complex and VEGF-R1 in men, and all biomarkers in women, were associated with clinical symptoms of UCPPS. None of the evaluated candidate markers usefully discriminated UCPPS patients from controls. Elevated VEGF, MMP-9 and VEGF-R1 levels in men and VEGF levels in women may provide potential new insights into the pathophysiology of UCPPS.

The water avoidance stress induces bladder pain due to a prolonged alpha1A adrenoceptor stimulation

Bladder Pain Syndrome/Interstitial Cystitis (BPS/IC) remains an elusive disease with the cause for the pain unclear. BPS/IC patients present increased sympathetic activity and high levels of urinary noradrenaline. At the experimental level, it has been shown that chronic adrenergic stimulation produces pain and bladder changes through an alpha 1A adrenoceptor mediated mechanism. Water avoidance stress (WAS) in rodents reproduces signs of nociception and bladder changes seen in BPS/IC patients. In this study, we explore the possible role of alpha 1A adrenoceptor in bladder pain and morphological changes. WAS was induced in a group of female Wistar rats. A separate WAS group received 0.2 mg/kg day silodosin (WAS + S). Lower abdominal pain was determined by performing sensitivity to Von Frey filaments. Bladder reflex activity was determined by cystometry in anaesthetised animals. Urine was collected for noradrenaline quantification by HPLC. Bladders were harvested and stained with Haematoxylin-eosin (to analyse urothelial morphology and to determine the disruption of surface umbrella cells) or with Toluidine Blue 0.1% to analyse mast cell infiltration. WAS increased urinary noradrenaline level and bladder frequency and decreased mechanical pain threshold, which was reversed by silodosin. WAS induced lymphocytic and mast cells infiltration in the mucosa and mild urothelial disruption, which was absent in WAS + S group. Alpha 1A adrenoceptor stimulation has an important role in the appearance of bladder pain in rats. Since BPS/IC patients present high levels of noradrenaline, alpha 1A stimulation may be an additional trigger for bladder dysfunction presented by these patients. Further studies will determine the clinical relevance of this finding in the treatment of BPS/IC patients.

Functional urological disorders: a sensitized defence response in the bladder-gut-brain axis

Functional urological and gastrointestinal disorders are interrelated and characterized by a chronic course and considerable treatment resistance. Urological disorders associated with a sizeable functional effect include overactive bladder (OAB), interstitial cystitis/bladder pain syndrome (IC/BPS), and chronic prostatitis/chronic pelvic pain syndrome (CP/CPPS). Poor treatment outcomes might be attributable to untreated underlying psychological and psychiatric disorders, as the co-occurrence of functional urological and gastrointestinal disorders with mood and anxiety disorders is common. The hypothetical bladder-gut-brain axis (BGBA) is a useful framework under which this interaction can be studied, suggesting that functional disorders represent a sensitized response to earlier threats such as childhood adversity or previous traumatic events, resulting in perceived emotional and bodily distress - the symptoms of functional disorders. Psychological and physical stress pathways might contribute to such alarm falsification, and neuroticism could be a risk factor for the co-occurrence of functional disorders and affective conditions. Additionally, physical threat - either from external sources or internal sources such as infection - might contribute to alarm falsification by influencing body-brain crosstalk on homeostasis and, therefore, affecting mood, cognition, and behaviour. Multidisciplinary research and an integrated care approach is, therefore, required to further elucidate and remediate functional urological and gastrointestinal polymorphic phenotypes.

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

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

A Stress-Related Peptide Bombesin Centrally Induces Frequent Urination through Brain Bombesin Receptor Types 1 and 2 in the Rat

Stress exacerbates symptoms of bladder dysfunction including overactive bladder and bladder pain syndrome, but the underlying mechanisms are unknown. Bombesin-like peptides and bombesin receptor types 1 and 2 (BB1 and BB2, respectively) in the brain have been implicated in the mediation/integration of stress responses. In this study, we examined effects of centrally administered bombesin on micturition, focusing on their dependence on 1) the sympathoadrenomedullary system (a representative mechanism activated by stress exposure) and 2) brain BB receptors in urethane-anesthetized (1.0-1.2 g/kg, i.p.) male rats. Intracerebroventricularly administered bombesin significantly shortened intercontraction intervals (ICI) at both doses (0.1 and 1 nmol/animal) without affecting maximal voiding pressure. Bombesin at 1 nmol induced significant increments of plasma noradrenaline and adrenaline levels, which were both abolished by acute bilateral adrenalectomy. On the other hand, adrenalectomy showed no effects on the bombesin-induced shortening of ICI. Much lower doses of bombesin (0.01 and 0.03 nmol/animal, i.c.v.) dose-dependently shortened ICI. Pretreatment with either a BB1 receptor antagonist (BIM-23127; d-Nal-cyclo[Cys-Tyr-d-Trp-Orn-Val-Cys]-Nal-NH2; 3 nmol/animal, i.c.v.) or a BB2 receptor antagonist (BEA; H-d-Phe-Gln-Trp-Ala-Val-Gly-His-Leu-NHEt; 3 nmol/animal, i.c.v.), respectively, suppressed the BB (0.03 nmol/animal, i.c.v.)-induced shortening of ICI, whereas each antagonist by itself (1 and 3 nmol/animal, i.c.v.) had no significant effects on ICI. Bombesin (0.03 nmol/animal, i.c.v.) significantly reduced voided volume per micturition and bladder capacity without affecting postvoid residual volume or voiding efficiency. These results suggest that brain bombesin and BB receptors are involved in facilitation of the rat micturition reflex to induce bladder overactivity, which is independent of the sympathoadrenomedullary outflow modulation.

Social stress in mice induces urinary bladder overactivity and increases TRPV1 channel-dependent afferent nerve activity

Social stress has been implicated as a cause of urinary bladder hypertrophy and dysfunction in humans. Using a murine model of social stress, we and others have shown that social stress leads to bladder overactivity. Here, we show that social stress leads to bladder overactivity, increased bladder compliance, and increased afferent nerve activity. In the social stress paradigm, 6-wk-old male C57BL/6 mice were exposed for a total of 2 wk, via barrier cage, to a C57BL/6 retired breeder aggressor mouse. We performed conscious cystometry with and without intravesical infusion of the TRPV1 inhibitor capsazepine, and measured pressure-volume relationships and afferent nerve activity during bladder filling using an ex vivo bladder model. Stress leads to a decrease in intermicturition interval and void volume in vivo, which was restored by capsazepine. Ex vivo studies demonstrated that at low pressures, bladder compliance and afferent activity were elevated in stressed bladders compared with unstressed bladders. Capsazepine did not significantly change afferent activity in unstressed mice, but significantly decreased afferent activity at all pressures in stressed bladders. Immunohistochemistry revealed that TRPV1 colocalizes with CGRP to stain nerve fibers in unstressed bladders. Colocalization significantly increased along the same nerve fibers in the stressed bladders. Our results support the concept that social stress induces TRPV1-dependent afferent nerve activity, ultimately leading to the development of overactive bladder symptoms.

Correlation between psychological stress levels and the severity of overactive bladder symptoms

Background

The relationship between psychological stress and interstitial cystitis/bladder pain syndrome (IC/BPS) has been well described. Even though there is some overlapping of symptoms between overactive bladder (OAB) and IC/BPS, there have been very few studies that specifically investigated the relationship between psychological stress and urinary symptoms in OAB patients who do not have pelvic pain. Here we examined the relationship between psychological stress levels and the severity of overactive bladder (OAB) symptoms.

Methods

Patients diagnosed with OAB (n=51), IC/BPS (n=27), and age-matched healthy controls (n=30) participated in a case control study that inquired about their psychological stress levels using the perceived stress scale (PSS). PSS reported by the three patient groups were compared. Among OAB patients, their responses on the PSS was correlated to OAB symptoms using the following questionnaires: 1) international consultation on incontinence – urinary incontinence (ICIQ-UI), 2) international consultation on incontinence – overactive bladder (ICIQ-OAB), 3) OAB-q short form, 4) urogenital distress inventory (UDI-6), 5) incontinence impact questionnaire (IIQ-7), 6) urgency severity scale (USS), 7) numeric rating scales of urgency symptom, and 8) frequency symptom. Spearman’s correlation tests were performed to examine the relationship between psychological stress levels and the severity of OAB symptoms.

Results

OAB patients reported psychological stress levels that were as high as IC/BPS patients (median 17.0 versus 18.0, p=0.818, Wilcoxon sum rank test), and significantly higher than healthy controls (17.0, versus 7.5, p=0.001). Among OAB patients, there was a positive correlation between perceived stress levels and urinary incontinence symptoms (ICIQ-UI, Spearman’s correlation coefficient=0.39, p=0.007), and impacts on quality of life (UDI-6, IIQ-7, OAB-q quality of life subscale; Spearman’s correlation coefficient=0.32, 0.31, 0.39, and p=0.028, 0.005, 0.029, respectively). No significant correlation was observed between perceived stress levels and urgency or frequency symptoms (ICIQ-OAB, USS, numeric ratings of urgency and frequency).

Conclusions

OAB patients reported psychological stress levels that were as high as IC/BPS patients, and significantly higher than healthy controls. There was a positive correlation between perceived stress levels and urinary incontinence symptoms, and its impacts on quality of life among OAB patients.

The amygdala central nucleus is required for acute stress-induced bladder hyperalgesia in a rat visceral pain model

Chronic stress has been implicated in the pathogenesis of chronic visceral pain conditions, such as interstitial cystitis (IC), and bouts of acute stress exacerbate clinical urological pain. Studies using animal models have shown that exposure to chronic footshock stress augments reflex responses to urinary bladder distension (UBD) in animal models, however acute effects in animal models are largely unknown, as are the central nervous system mechanisms of stress-related increases in nociception. The amygdala is a salient structure for integration of sensory and cognitive/emotional factors. The present study determined the role of the central nucleus of the amygdala (CeA) in stress-related bladder hypersensitivity. We examined the effects of CeA manipulations (lesions and chemical stimulation) on visceromotor responses (abdominal muscle contractions) to UBD in adult, female Sprague-Dawley rats. We report that acute footshock stress produces bladder hyperalgesia that can be prevented by bilateral CeA lesions, despite no effect of lesions on baseline somatic sensation, as indicated by flinch/jump thresholds to electrical shock. Further, acute glucocorticoid stimulation of the CeA recapitulated stress-induced hyperalgesia. Of note is that CeA lesions, but not chemical stimulation, significantly affected HPA axis activation, as indicated by measurements of circulating corticosterone. Our findings conclusively show that the CeA is necessary for the generation of bladder hyperalgesia in response to acute stress. The CeA may play multiple stress-related roles in nociceptive modulation, i.e., via direct facilitation of the HPA axis during acute stress, or via modulation of other systems that augment acute stress responsiveness.

Changes in symptoms during urologic chronic pelvic pain syndrome symptom flares: findings from one site of the MAPP Research Network

AIMS

To provide the first description and quantification of symptom changes during interstitial cystitis/bladder pain syndrome and chronic prostatitis/chronic pelvic pain syndrome symptom exacerbations ("flares").

METHODS

Participants at one site of the Trans-Multidisciplinary Approaches to the study of chronic Pelvic Pain Epidemiology and Phenotyping Study completed two 10-day diaries over the 1-year study follow-up period, one at baseline and one during their first flare (if not at baseline). On each day of the diary, participants reported whether they were currently experiencing a flare, defined as "symptoms that are much worse than usual" for at least 1 day, and their levels of urination-related pain, pelvic pain, urgency, and frequency on a scale of 0-10. Linear mixed models were used to calculate mean changes in symptoms between non-flare and flare days from the same participant.

RESULTS

Eighteen of 27 women and 9 of 29 men reported at least one flare during follow-up, for a total of 281 non-flare and 210 flare days. Of these participants, 44.4% reported one flare, 29.6% reported two flares, and 25.9% reported ≥ 3 flares over the combined 20-day diary observation period, with reported flares ranging in duration from 1 day to >2 weeks. During these flares, each of the main symptoms worsened significantly by a mean of at least two points and total symptoms worsened by a mean of 11 points for both sexes (all P ≤ 0.01).

CONCLUSIONS

Flares are common and correspond to a global worsening of urologic and pelvic pain symptoms.

Bladder pain syndrome/interstitial cystitis as a functional somatic syndrome

PURPOSE

To determine whether bladder pain syndrome/interstitial cystitis (BPS/IC) has the characteristics of a functional somatic syndrome (FSS).

MATERIALS AND METHODS

There is no accepted definition of an FSS. Consequently, this paper reviewed the literature for common FSS characteristics and for reports that BPS/IC has these characteristics.

RESULTS

Eleven articles met inclusion and exclusion criteria and yielded 18 FSS characteristics. BPS/IC patients manifest all but two: the exceptions were normal light microscopic anatomy (after hydrodistention under anesthesia, some BPS/IC bladders have Hunner's lesions and most have petechial hemorrhages) and normal laboratory tests (many BPS/IC patients have hematuria). Petechial hemorrhages and hematuria are probably related and may appear during naturally-occurring bladder distention. Without such distention, then, the 90% of BPS/IC patients without a Hunner's lesion have all the characteristics of an FSS. Comparisons in the opposite direction were consistent: several additional features of BPS/IC were found in FSSs.

CONCLUSIONS

This systematic but untested method is consistent with but does not test the hypothesis that BPS/IC in some patients might best be understood as an FSS. Like most conditions, BPS/IC is probably heterogeneous; hence only a proportion of BPS/IC cases are likely to be manifestations of an FSS. This hypothesis has several implications. Explorations of processes that connect the FSSs might contribute to understanding the pathogenesis of BPS/IC. Patients with FSSs are at risk for BPS/IC and may benefit from future preventive strategies. Therapies that are useful in FSSs also may be useful in some cases of BPS/IC.

Chronic psychological stress in high-anxiety rats induces sustained bladder hyperalgesia

OBJECTIVE

To evaluate whether anxiety-prone rats exposed to chronic water avoidance stress (WAS) develop visceral bladder hyperalgesia in addition to increased voiding frequency and anxiety-related behaviors.

MATERIALS AND METHODS

Female Wistar-Kyoto (WKY) rats were exposed to chronic (10-day) WAS or sham paradigms. Referred hyperalgesia and tactile allodynia were tested using von Frey filaments applied to the suprapubic region and plantar region of the hindpaw, respectively. To confirm that suprapubic nociception represented referred visceral bladder hyperalgesia, we recorded abdominal visceromotor responses (VMR) to slow (100 μl/min) and fast (1 cc/sec) bladder filling with room temperature or ice-cold saline. We assessed the development of hyperalgesia over the 10-day WAS protocol and the durability of increased pain sensations over time.

RESULTS

Animals exposed to chronic WAS had significantly lower hindpaw withdrawal thresholds post-stress and significant differences in referred hyperalgesia. Rats exposed to chronic WAS demonstrated an increased pain response to suprapubic stimulation and decreased response threshold to mechanical hindpaw stimulation by day 8 of the stress protocol, which persisted for more than one month. Animals exposed to chronic WAS showed increased VMR to fast filling and ice water testing in comparison to sham animals. Cystometry under anesthesia did not show increases in the frequency of non-voiding contractions.

CONCLUSION

Chronic WAS induces sustained bladder hyperalgesia, lasting over a month after exposure to stress. The urinary frequency demonstrated previously in anxiety-prone rats exposed to chronic WAS seems to be associated with bladder hyperalgesia, suggesting that this is a potential model for future studies of bladder hypersensitivity syndromes such as interstitial cystitis/painful bladder syndrome (IC/PBS).

Glucocorticoid mediates water avoidance stress-sensitized colon-bladder cross-talk via RSK2/PSD-95/NR2B in rats

Unexpected environmental and social stimuli could trigger stress. Although coping with stress is essential for survival, long-term stress impacts visceral functions, and therefore, it plays a role in the development and exacerbation of symptoms of gastrointestinal/urogenital disorders. The aim of this study is to characterize the role of corticosterone in stress-sensitized colon-bladder cross-talk, a phenomenon presumed to underlie the comorbidity of functional bowel and bladder disorders. Cystometry and protein/mRNA expression in the lumbosacral dorsal horn (L6-S1) in response to intracolonic mustard oil (MO) instillation were analyzed in female Wistar-Kyoto rats subjected to water avoidance stress (WAS; 1 h/day for 10 days) or sham stress (WAsham). Whereas it had no effect on baseline-voiding function, chronic stress upregulated plasma corticosterone concentration and dorsal horn spinal p90 ribosomal S6 kinase 2 (RSK2) protein/mRNA levels, and RSK2 immunoreactivity colocalized with NeuN-positive neurons. Intracolonic MO dose-dependently decreased intrercontraction intervals and threshold pressure, provoked spinal RSK2 and NR2B phosphorylation, and enhanced PSD-95-RSK2 and PSD-95-NR2B coupling. Intrathecal kaempferol (a RSK2 activation antagonist; 30 min before MO instillation), bilateral adrenalectomy (7 days prior the stress paradigm), and subcutaneous RU-38486 (a glucocorticoid receptor antagonist; 30 min daily before stress sessions), but not RU-28318 (a mineralocorticoid receptor antagonist), attenuated MO-induced bladder hyperactivity, protein phosphorylation, and protein-protein interactions in the WAS group. Our results suggest that stress-associated glucocorticoid release mediates WAS-dependent sensitization of colon-bladder cross-talk via the spinal RSK2/PSD-95/NR2B cascade and offer a possibility for developing pharmacological strategies for the treatment of stress-related pelvic pain.

A modulating effect of epigallocatechin gallate (EGCG), a tea catechin, on the bladder of rats exposed to water avoidance stress

AIMS

To examine the effect of epigallocatechin gallate (EGCG), a green tea catechin, on the bladder of rats exposed to water avoidance stress (WAS).

METHODS

Twenty female Sprague-Dawley rats were divided into four groups of five. The first group was exposed to WAS for7 days. The second group was pretreated with EGCG 1 mg/kg intraperitoneally (IP) for 7 days before exposure to WAS. The treatment was continued till the end of the experiment. The third group was placed on the platform in a container without water for 2 hr daily for 7 days (Sham WAS). The fourth group was pretreated with saline I.P. for 7 days before being exposed to sham WAS.

PRIMARY OUTCOME

Bladder wall evaluation for signs of inflammation and total and activated mast cell counts. Secondary outcome: fecal pellet output and micturition frequency at baseline, day 1 and day 7.

RESULTS

Bladder walls from rats exposed to WAS revealed significantly higher inflammation score, total and degranulated mast cell counts compared to the sham WAS group. EGCG administration had an obvious protective effect on the bladder mucosa, as the inflammation score, total and degranulated mast cell counts were all significantly lower than in the WAS group. In the WAS group, fecal pellet output and micturition frequency increased above baseline throughout the experiment. Comparison of sham WAS group versus sham WAS with saline revealed no statistically significant difference in any parameter.

CONCLUSIONS

EGCG given at 1 mg/kg I.P to rats has a significant protective effect against bladder degenerative changes following WAS.

Footshock stress differentially affects responses of two subpopulations of spinal dorsal horn neurons to urinary bladder distension in rats

This investigation examined the effect of footshock on responses of 283 spinal dorsal horn neurons (DHNs) to urinary bladder distension (UBD). Female rats were treated with seven daily sessions of footshock (chronic footshock, CFS), six accommodation sessions followed by one exposure to footshock (acute footshock, AFS) or handled similarly without receiving any footshock (no footshock, NFS). After the final footshock or NFS session, rats were anesthetized, a laminectomy performed and extracellular single-unit recordings of L6-S1 DHNs obtained in intact or spinalized preparations. Neurons were classified as Type I-inhibited by heterotopic noxious conditioning stimuli (HNCS) or as Type II-not inhibited by HNCS-and characterized for spontaneous activity and for neuronal discharges evoked by graded UBD. A differential effect of footshock-induced stress was noted on neuronal subgroups. In intact preparations, Type I neurons were less responsive to UBD after either chronic or acute stress, while Type II neurons demonstrated significantly augmented responses to UBD. This enhanced neuronal responsiveness to UBD was present in spinalized preparations following exposure to CFS but not AFS. Type I neurons were still less responsive to stress in spinalized preparations following CFS and AFS. This study provides further evidence that (1) at least two populations of spinal neurons exist which encode for visceral stimuli and are likely to have distinct roles in visceral nociception, and that (2) the chronic stress-induced enhancement of DHN responses to UBD involves changes at the spinal level while the acute stress effects are dependent on a supraspinal substrate.

Corticotropin-releasing hormone-receptor 2 is required for acute stress-induced bladder vascular permeability and release of vascular endothelial growth factor

OBJECTIVE

To investigate the corticotropin-releasing hormone (CRH) receptor (CRH-R) requirement for the effect of acute stress on bladder vascular permeability and release of vascular endothelial growth factor (VEGF), as increasing evidence indicates that acute stress worsens certain inflammatory disorders, including interstitial cystitis/painful bladder syndrome (IC/PBlS), which is characterized by pain, variable bladder inflammation, increased expression of bladder vascular endothelial growth factor (VEGF), and many detrusor mast cells.

MATERIALS AND METHODS

Bladders of normal C57BL/6, and C57BL/6- derived CRH-R1, CRH-R2 or double CRH-R1 + 2 knockout (-/-) female mice (10-12 weeks old) were catheterized under anaesthesia. After emptying the urine, normal saline was instilled with or without intravesical CRH-R antagonists in C57BL/6 mice before they were stressed by placing them in a restrainer for 30 min. Evans blue was injected in the tail vein before stress for the permeability experiments. The bladders from C57BL/6 or CRH-R -/- mice were then removed, minced into 1 mm(2) pieces and cultured overnight. Culture media were collected 24 h later for VEGF assay. C57BL/6 bladder was processed for CRH-R immunohistochemistry.

RESULTS

Acute stress increased bladder vascular permeability in control C57BL/6 and CRH-R1 -/- mice, but not CRH-R2 -/- or CRH-R1+2 -/- mice. The CRH-R2 antagonist Astressin 2B, but not the CRH-R1 antagonist Antalarmin, inhibited stress-induced VEGF release from C57BL/6 mouse bladder explants. Stress could not induce a VEGF increase from bladder explants of CRH-R2 -/- or CRH-R1+2 -/- mice, but did so in CRH-R1 -/- mice. Bladder CRH-R2 immunoreactivity was detected in C57BL/6 bladders.

CONCLUSIONS

Acute stress induces bladder vascular permeability and VEGF release that is dependent on CRH-R2. These findings suggest that CRH and VEGF might participate in the pathogenesis of IC/PBlS and provide for new therapeutic targets.

The relationship between sexual abuse and interstitial cystitis/painful bladder syndrome

Interstitial cystitis/painful bladder syndrome (IC/PBS) is a chronic syndrome characterized by irritative voiding symptoms and pelvic pain or discomfort. IC/PBS represents localized bladder pathophysiologic changes and central nervous system upregulation. Patients exhibit bladder hyperalgesia and allodynia. Childhood sexual abuse occurs in up to 27% of females in the United States. Adults with a prior history of abuse or traumatization demonstrate hypothalamic-pituitary-adrenal (HPA) axis abnormalities, similar to IC/PBS patients. Childhood sexual abuse and physical traumatization are associated with subsequent lifelong risks of chronic pain syndromes. IC/PBS patients have increased rates of sexual abuse or physical traumatization histories compared with controls. IC/PBS patients with abuse histories tend to have greater pain intensity and lesser irritative voiding symptoms compared with nonabused IC/PBS patients. This article reviews the relationship between sexual abuse, HPA axis abnormalities, IC/PBS pathophysiology, and the role of sexual abuse on subsequent IC/PBS.