Treatment approaches for painful bladder syndrome/interstitial cystitis

Dietary proanthocyanidins on gastrointestinal health and the interactions with gut microbiota

Many epidemiological and experimental studies have consistently reported the beneficial effects of dietary proanthocyanidins (PAC) on improving gastrointestinal physiological functions. This review aims to present a comprehensive perspective by focusing on structural properties, interactions and gastrointestinal protection of PAC. In brief, the main findings of this review are summarized as follows: (1) Structural features are critical factors in determining the bioavailability and subsequent pharmacology of PAC; (2) PAC and/or their bacterial metabolites can play a direct role in the gastrointestinal tract through their antioxidant, antibacterial, anti-inflammatory, and anti-proliferative properties; (3) PAC can reduce the digestion, absorption, and bioavailability of carbohydrates, proteins, and lipids by interacting with them or their according enzymes and transporters in the gastrointestinal tract; (4). PAC showed a prebiotic-like effect by interacting with the microflora in the intestinal tract, and the enhancement of PAC on a variety of probiotics, such as Bifidobacterium spp. and Lactobacillus spp. could be associated with potential benefits to human health. In conclusion, the potential effects of PAC in prevention and alleviation of gastrointestinal diseases are remarkable but clinical evidence is urgently needed.

Clinical Management of Chronic Pelvic Pain in Endometriosis Unresponsive to Conventional Therapy

Background: Although several treatments are currently available for chronic pelvic pain, 30–60% of patients do not respond to them. Therefore, these therapeutic options require a better understanding of the mechanisms underlying endometriosis-induced pain. This study focuses on pain management after failure of conventional therapy. Methods: We reviewed clinical data from 46 patients with endometriosis and chronic pelvic pain unresponsive to conventional therapies at Puerta de Hierro University Hospital Madrid, Spain from 2018 to 2021. Demographic data, clinical and exploratory findings, treatment received, and outcomes were collected. Results: Median age was 41.5 years, and median pain intensity was VAS: 7.8/10. Nociceptive pain and neuropathic pain were identified in 98% and 70% of patients, respectively. The most common symptom was abdominal pain (78.2%) followed by pain with sexual intercourse (65.2%), rectal pain (52.1%), and urologic pain (36.9%). A total of 43% of patients responded to treatment with neuromodulators. Combined therapies for myofascial pain syndrome, as well as treatment of visceral pain with inferior or superior hypogastric plexus blocks, proved to be very beneficial. S3 pulsed radiofrequency (PRF) plus inferior hypogastric plexus block or botulinum toxin enabled us to prolong response time by more than 3.5 months. Conclusion: Treatment of the unresponsive patient should be interdisciplinary. Depending on the history and exploratory findings, therapy should preferably be combined with neuromodulators, myofascial pain therapies, and S3 PRF plus inferior hypogastric plexus blockade.

Pharmacotherapeutic advances for recurrent urinary tract infections in women

INTRODUCTION

Treatment of recurrent Urinary tract infections (UTIs) has become challenging because of the dramatic increase in the rates of recurrent infection andof multidrug-resistant (MDR) infections.

AREAS COVERED

The authors review recurrent UTIs(rUTI) management in women.

EXPERT OPINION

Continuous or post-coital prophylaxis with low-dose antimicrobials or intermittent self-treatment has all been demonstrated to be effective in managing rUTIs in women. Intravaginal estrogen therapy , shows potential toward preventing rUTI. Oral vaccine Uro-Vaxom seems to reduce the number of UTIs. There is evidence that other therapies (e.g. cranberry, Methenamine hippurate, oral D-mannose) may decrease the number of symptomatic UTIs. The treatment of CRE-UTIs is focused on a colistin backbone. Carbapenems are considered first-line agents for UTIs caused by ESBL, but their use is associated with increased MDR. The usage of non-carbapenem for the treatment of ESBL UTIs is necessary. Cefepime, Piperacillin-Tazobactam, Ceftolozane-Tazobactam, and Ceftazidime-Avibactam are justified options. Oral therapy with Pivmecillinam, Fosfomycin, and Nitrofurantoin can be used against uncomplicated UTIs due to ESBL infection.

The Potential Use of Grape Phytochemicals for Preventing the Development of Intestine-Related and Subsequent Inflammatory Diseases

BACKGROUND

Grape phytochemicals prevent intestine-related and subsequent other inflammatory diseases. Phytochemicals and vitamin D are useful for the regulation of inflammatory responses. Phytochemicals is the generic name for terpenoids, carotenoids, and flavonoids that consist of a variety of chemicals contained in vegetables and fruits. There are a variety of grape cultivars that contain many kinds of phytochemicals in their skin and seeds. Grape phytochemicals including Grape Seed Extracts (GSE) have already been used to maintain healthy condition through manipulating inflammatory responses by decreasing the expression of inflammation-related factors.

DISCUSSION

Grape phytochemicals mainly consist of a variety of chemicals that include terpenoid (oleanolic acid), carotenoids (β-carotene, lutein), and flavonoids: flavon-3-ols (quercetin), flavan-3-ols (catechins), anthocyanins, oligomers and polymers (tannins and proanthocyanidins), and resveratrol. Phytochemicals improve the dysbiosis (gut microbiota complication) induced by metabolic syndrome and regulate inflammatory diseases induced by TNF-α production. Once absorbed, flavonoids change into glucuronide-form, move into the bloodstream and reach the inflammatory sites including liver, lung, and sites of arteriosclerosis, where they become active. Furthermore, oleanolic acid acts on TGR5 - the cholic acid receptor, as an agonist of cholic acid. These anti-inflammatory effects of phytochemicals have been proven by the experimental animal studies and the clinical trials.

CONCLUSION

It is expected the new health food products will be created from grape skins and seeds since grape phytochemicals participate in the prevention of inflammatory diseases like intestine-related inflammatory diseases.

Sympathetic afferents in the hypogastric nerve facilitate nociceptive bladder activity in cats

This study in α-chloralose-anesthetized cats revealed a role of hypogastric nerve afferent axons in nociceptive bladder activity induced by bladder irritation using 0.25% acetic acid (AA). In cats with intact hypogastric and pelvic nerves, AA irritation significantly ( P < 0.05) reduced bladder capacity to 45.0 ± 5.7% of the control capacity measured during a saline cystometrogram (CMG). In cats with the hypogastric nerves transected bilaterally, AA irritation also significantly ( P < 0.05) reduced bladder capacity, but the change was significantly smaller (capacity reduced to 71.5 ± 10.6% of saline control, P < 0.05) than that in cats with an intact hypogastric nerve. However, application of hypogastric nerve stimulation (HGNS: 20 Hz, 0.2 ms pulse width) to the central end of the transected nerves at an intensity (16 V) strong enough to activate C-fiber afferent axons facilitated the effect of AA irritation and further ( P < 0.05) reduced bladder capacity to 48.4 ± 7.4% of the saline control. This facilitation by HGNS was effective only at selected frequencies (1, 20, and 30 Hz) when the stimulation intensity was above the threshold for activating C-fibers. Tramadol (an analgesic agent) at 3 mg/kg iv completely blocked the nociceptive bladder activity and eliminated the facilitation by HGNS. HGNS did not alter non-nociceptive bladder activity induced by saline distention of the bladder. These results indicate that sympathetic afferents in the hypogastric nerve play an important role in the facilitation of the nociceptive bladder activity induced by bladder irritation that activates the silent C-fibers in the pelvic nerve.

Bridging pharmacotherapy and minimally invasive surgery in interstitial cystitis/bladder pain syndrome treatment

INTRODUCTION

Interstitial cystitis/bladder pain syndrome (IC/BPS) is a painful and debilitating clinical entity which is challenging to diagnose and even more difficult to treat. Unfortunately, none of the existing oral and intravesical medications have been established as effective and therefore relevant research is ongoing. Areas covered: In this review, the authors present established and emerging treatment options for IC/BPS in terms of medication and minimal invasive procedures. Both American and European Urological Association Guidelines recommend multimodal behavioral techniques alongside oral (e.g. amitriptyline and pentosan polysulfate sodium) or minimally invasive treatments (e.g. dimethyl sulfoxide, botulinum toxin, chondroitin sulfate, triamcinolone, hyaluronic acid, and lidocaine). Novel treatment modalities include immunomodulating drugs, stem cell therapy, nerve growth factor, and ASP6294. Expert opinion: IC/BPS is still a pathophysiological enigma with multifactorial etiopathogenesis that may be controlled but not completely cured. Patient-tailored phenotype-directed multimodal therapy is the most promising treatment strategy. Combined phenotypic categorization with specific biomarkers could help toward better treatment.

Risk for Irritable Bowel Syndrome in Fibromyalgia Patients: A National Database Study

Various studies have shown that irritable bowel syndrome (IBS) is highly associated with other pathologies, including fibromyalgia (FM). The objective of this study was to analyze the differences among risk factors associated with IBS following FM in a nationwide prospective cohort study.We propose that a relationship exists between FM and IBS. This article presents evidence obtained from a cohort study in which we used data from the Taiwan National Health Insurance Research Database to clarify the relationship between FM and IBS. The follow-up period ran from the start of FM diagnosis to the date of the IBS event, censoring, or December 31, 2011. We analyzed the risk of IBS using Cox proportional hazard regression models, including sex, age, and comorbidities.During the follow-up period, from 2000 to 2011, the overall incidence of IBS was higher in FM patients than in non-FM patients (7.47 vs 4.42 per 1000 person-years), with a crude hazard ratio = 1.69 (95% confidence interval [CI] 1.59-1.79). After adjustment for age, sex, and comorbidities, FM was associated with a 1.54-fold increased risk for IBS.Mutually risk factors may influence the relationship between FM and IBS. We recommend that physiologists conduct annual examinations of FM patients to reduce the incidence of IBS progression.

Effects of quercetin on chronic constriction nerve injury in an experimental rat model

BACKGROUND

Flavonoids are popular substances in the literature, with proven effects on cardiovascular, neoplastic and neurodegenerative diseases. Antioxidant effect is the most pronounced and studied one. Among thousands of flavonoids, quercetin (QUE) is a prototype with significant antioxidant effects. This study aims to demonstrate the effects of QUE in an experimental rat model of chronic constriction injury (CCI).

METHOD

A two-level study was designed with 42 adult Wistar rats that were randomly assigned to different groups. In the first part, animals in sham, control, quercetin, morphine and gabapentine groups received chronic constriction injury to their sciatic nerves and received a single dose of QUE, morphine and gabapentine. In the second part, different dose regimens of QUE were administered to different groups of animals. Pre-injury and post-injury assessments for mechanical hypersensitivity, thermal sensitivity, locomotor activity and anxiety were recorded and statistical comparisons were performed between different groups.

RESULTS

Comparison of QUE with morphine and gabapentine has revealed significant effects of this agent in the current chronic constriction injury model. QUE was significantly superior to Gabapentine and morphine in terms of alleviating mechanical and thermal hypersensitivity. Additionally, pre-injury administration of QUE for 4 days demonstrated long-term effectiveness on mechanical hypersensitivity.

CONCLUSIONS

This preliminary report the on effects of QUE in a chronic constriction injury model proved significant effects of the agent, which should be supplemented with different studies using different dose regimens.

Nursing Care of Women With Interstitial Cystitis/Painful Bladder Syndrome

Interstitial cystitis/painful bladder syndrome is a chronic condition affecting approximately 3.3 million women in the United States. It is defined by the National Institute of Diabetes and Digestive and Kidney Diseases as "urinary pain that can't be attributed to other causes such as infection or urinary stones." Because of the intimate nature of the symptoms, women are often reluctant to seek treatment. When they do, they require a care provider with specialized nursing skills. Nursing practice based on carefully reviewed literature will result in the provision of comprehensive and compassionate nursing care for women with interstitial cystitis/painful bladder syndrome.

Risk for irritable bowel syndrome in fibromyalgia patients: a national database study

Various studies have shown that irritable bowel syndrome (IBS) is highly associated with other pathologies, including fibromyalgia (FM). The objective of this study was to analyze the differences among risk factors associated with IBS following FM in a nationwide prospective cohort study. We propose that a relationship exists between FM and IBS. This article presents evidence obtained from a cohort study in which we used data from the Taiwan National Health Insurance Research Database to clarify the relationship between FM and IBS. The follow-up period ran from the start of FM diagnosis to the date of the IBS event, censoring, or December 31, 2011. We analyzed the risk of IBS using Cox proportional hazard regression models, including sex, age, and comorbidities. During the follow-up period, from 2000 to 2011, the overall incidence of IBS was higher in FM patients than in non-FM patients (7.47 vs 4.42 per 1000 person-years), with a crude hazard ratio = 1.69 (95% confidence interval [CI] 1.45-1.63). After adjustment for age, sex, and comorbidities, FM was associated with a 1.54-fold increased risk for IBS. Mutually risk factors may influence the relationship between FM and IBS. We recommend that physiologists conduct annual examinations of FM patients to reduce the incidence of IBS progression.

Efficacy of daily low-dose sildenafil for treating interstitial cystitis: results of a randomized, double-blind, placebo-controlled trial--treatment of interstitial cystitis/painful bladder syndrome with low-dose sildenafil

OBJECTIVE

To evaluate the efficacy of daily low-dose sildenafil for the treatment of nonulcer interstitial cystitis (IC) in women.

PATIENTS AND METHODS

Forty-eight women with a clinical diagnosis of IC from 3 medical centers were randomly assigned to treatment with daily low-dose sildenafil (25 mg, n=24) or placebo (n=24) for 3 months. The O'Leary-Sant IC symptom and problem indices, visual analog scale scores, and a micturition diary with the interval of micturition, the frequency of nocturia, and urgency episodes were recorded before treatment, every 2 weeks after the treatment until 3 months. Patient Overall Rating of Improvement in Symptoms was assessed and regarded as effective when the value was above 50%.

RESULTS

The IC symptom and problem indices scores and urodynamic index were significantly improved in sildenafil treatment group as compared with placebo group and baselines at week 4, 6, 8, 10, and 12, as well as 3 months after treatment (P<.05). Urodynamic index including first desire to void, strong desire to void, and maximum cystometric capacity was significantly improved in sildenafil treatment group at week 12 and at 3 months after treatment (P<.05). The efficiency of treatment reached 62.5%. However, no significant change of the visual analog scale values was observed between 2 groups except at week 12 in the sildenafil treatment group (P<.05). All adverse events were mild to moderate and transient.

CONCLUSION

Daily low-dose sildenafil is an easy, well-tolerated, and effective treatment for IC in women.

Effects of combination treatment of intravesical resiniferatoxin instillation and hydrodistention in patients with refractory painful bladder syndrome/interstitial cystitis: a pilot study

PURPOSE

Painful bladder syndrome/interstitial cystitis (PBS/IC) is a disabling disease of the urinary bladder, and its etiology and treatment are not yet established. Current medications used in the treatment of PBS/IC have shown limited efficacy. This prospective study investigated the efficacy of intravesical resiniferatoxin (RTX) in PBS/IC refractory to medical treatment.

METHODS

Patients with proven PBS/IC refractory to traditional medical treatment were enrolled. By randomized trial, a total of 18 consecutive patients were divided into two groups: treatment with hydrodistention and intravesical RTX (group 1) or treatment with hydrodistension only (group 2). We assessed bladder pain by use of a visual analogue pain scale, the maximal urine flow rate, post-void residual urine volume, and a voiding diary before and 3 months after treatment.

RESULTS

The median age of the 18 patients was 55.8±6.9 years, and the median duration of symptoms before diagnosis was 3.6±1.6 years. Frequency, functional bladder capacity, and score on a 5-point pain scale were significantly improved at 3-month after treatment in both groups. Intravesical RTX instillation plus hydrodistention, compared with hydrodistention only, did not have a significant effect on the voiding symptoms or uroflowmetry of the patients but significantly improved scores on the pain scale.

CONCLUSIONS

Intravesical RTX instillation plus hydrodistention was effective in relieving pain but was not effective in improving lower urinary tract symptoms. Further larger studies are needed to clarify the efficacy of combination treatment of intravesical RTX instillation and hydrodistention.

A murine model of inflammatory bladder disease: cathelicidin peptide induced bladder inflammation and treatment with sulfated polysaccharides

PURPOSE

Studies show that LL-37 is a naturally occurring urinary defensin peptide that is up-regulated during urinary tract infections. Although normal urinary LL-37 levels are antimicrobial, we propose that increased LL-37 may trigger bladder inflammation. We further suggest that anti-inflammatory sulfated polysaccharides known as semi-synthetic glycosaminoglycan ether compounds can treat/prevent LL-37 mediated bladder inflammation.

MATERIALS AND METHODS

C57BL/6 mice were catheterized/instilled with LL-37 (320 μM, 150 μl) for 45 minutes. Animals were sacrificed at 12 and 24 hours, and tissues were examined using hematoxylin and eosin. Separate experiments were performed for myeloperoxidase to quantify inflammation. GM-1111 semi-synthetic glycosaminoglycan ether treatments involved instillation of 10 mg/ml for 45 minutes directly before or after LL-37. Tissues were harvested at 24 hours. To compare semi-synthetic glycosaminoglycan ether efficacy, experiments were performed using 10 mg/ml heparin. Finally, tissue localization of semi-synthetic glycosaminoglycan ether was examined using a fluorescent GM-1111-Alexa Fluor® 633 conjugate.

RESULTS

Profound bladder inflammation developed after LL-37. Greater tissue inflammation occurred after 24 hours compared to that at 12 hours. Myeloperoxidase assays revealed a 21 and 61-fold increase at 12 and 24 hours, respectively. Semi-synthetic glycosaminoglycan ether treatment after LL-37 showed mild attenuation of inflammation with myeloperoxidase 2.5-fold below that of untreated bladders. Semi-synthetic glycosaminoglycan ether treatment before LL-37 demonstrated almost complete attenuation of inflammation. Myeloperoxidase results mirrored those in controls. In heparin treated bladders minimal attenuation of inflammation occurred. Finally, instillation of GM-1111-Alexa Fluor 633 revealed urothelial coating, significant tissue penetration and binding to endovasculature.

CONCLUSIONS

We developed what is to our knowledge a new model of inflammatory bladder disease by challenge with the naturally occurring urinary peptide LL-37. We also noted that a new class of anti-inflammatory sulfated polysaccharides prevents and mitigates bladder inflammation.

Chronic pelvic pain and endometriosis: translational evidence of the relationship and implications

BACKGROUND

Many clinicians and patients believe that endometriosis-associated pain is due to the lesions. Yet causality remains an enigma, because pain symptoms attributed to endometriosis occur in women without endometriosis and because pain symptoms and severity correlate poorly with lesion characteristics. Most research and reviews focus on the lesions, not the pain. This review starts with the recognition that the experience of pain is determined by the central nervous system (CNS) and focuses on the pain symptoms.

METHODS

Comprehensive searches of Pubmed, Medline and Embase were conducted for current basic and clinical research on chronic pelvic pain and endometriosis. The information was mutually interpreted by a basic scientist and a clinical researcher, both in the field of endometriosis. The goal was to develop new ways to conceptualize how endometriosis contributes to pain symptoms in the context of current treatments and the reproductive tract.

RESULTS

Endometriotic lesions can develop their own nerve supply, thereby creating a direct and two-way interaction between lesions and the CNS. This engagement provides a mechanism by which the dynamic and hormonally responsive nervous system is brought directly into play to produce a variety of individual differences in pain that can, in some women, become independent of the disease itself.

CONCLUSIONS

Major advances in improving understanding and alleviating pain in endometriosis will likely occur if the focus changes from lesions to pain. In turn, how endometriosis affects the CNS would be best examined in the context of mechanisms underlying other chronic pain conditions.

Risk factors for poor sleep quality among patients with interstitial cystitis in Taiwan

AIMS

Previous research has suggested that patients with interstitial cystitis have more sleep disturbances and higher levels of depression. However, reports that employ validated sleep questionnaires are rare for this population. The present study investigates the relationship between sleep quality, anxiety, depression, and the severity of urologic interstitial cystitis symptoms in outpatients, and risk factors for poor sleep quality.

METHODS

A total of 69 patients (52 female) with interstitial cystitis met National Institute of Arthritis, Diabetes, Digestive and Kidney Diseases (NIDDK) criteria, completed all instruments. The O'Leary-Sant Interstitial Cystitis Symptom Index (ICSI) was performed to assess interstitial cystitis severity. The Pittsburgh Sleep Quality Index (PSQI) and Hospital Anxiety and Depression Scale (HADS) were used to evaluate quality of sleep and depression level, respectively. Multiple linear regressions were used to identify independent factors of sleep quality.

RESULTS

Mean PSQI global score was 9.5 +/- 4.2 (range: 1-19); 81.2% of subjects had poor sleep quality (PSQI > 5). Regression analysis suggested that the severity of interstitial cystitis (Beta coefficient = 0.42, P < 0.001) and level of anxiety and depression (Beta coefficient = 0.26, P < 0.05) were significant independent risk factors for poor sleep quality, after controlling for age, gender, marital status, years of education, and years of symptomatic duration. Further analysis of ICSI subdomain scores shows that association between nighttime urination and poor sleep quality remains significantly (Beta coefficient = 0.32, P < 0.05), after adjustment for demographic data and anxiety and depression.

CONCLUSIONS

Poor sleep quality is common in interstitial cystitis patients and severity of urological symptoms and depression levels are important independent risk factors.

Interstitial cystitis: an unsolved enigma

Painful bladder syndrome/interstitial cystitis (PBS/IC) is a chronic disease of unknown etiology characterized by vague bladder pain and nonspecific urinary symptoms, such as urgency and frequency. Although it was initially considered to be a rare condition, its prevalence has significantly increased, possibly because of different definitions used and greater physician awareness. Because of the multiple diagnostic criteria used, there is significant variation in its prevalence. In addition, there is often a delay in the diagnosis of PBS/IC. It affects predominantly women of middle age, and it significantly decreases quality of life. Diagnosis of PBS/IC is mainly a diagnosis of exclusion; there are no characteristic symptoms or pathognomonic findings. Therefore, it is important to rule out diseases that have a similar clinical picture (i.e., urinary infections, bladder carcinoma) but definite therapies and worse prognosis if left untreated. PBS/IC management suffers from lack of evidence; many therapies are empiric or based on small studies and case series. Treatment includes supportive therapies (psychosocial, behavioral, physical), oral treatments, and intravesical treatments, whereas other more invasive treatments such as electric neuromodulation and reconstructive surgery are reserved for refractory cases. Physicians should always keep in mind the diagnosis of PBS/IC in patients presenting with chronic urinary symptoms after excluding other more common diseases.

Role of spinal microglia in visceral hyperalgesia and NK1R up-regulation in a rat model of chronic stress

BACKGROUND & AIMS

Chronic psychological stress is associated with visceral hyperalgesia and increased expression of spinal NK1 receptors (NK1Rs). We aimed to identify the role of spinal microglia in this process.

METHODS

Male Wistar rats were exposed to water avoidance (WA) or sham stress 1 hour each day for 10 days and given daily injections of minocycline, the p38 inhibitor SB203580, or saline. Phosphorylation levels of the kinase p38 (P-p38), the microglia marker OX42, NK1R, and IkappaBalpha were assessed by immunoblotting and/or immunostaining of spinal samples collected at day 11. The visceromotor response to colorectal distention at baseline and following WA were also assayed in rats given injections of minocycline, SB203580, or vehicle. The effects of fractalkine were assessed on the visceromotor response in rats exposed to minocycline or vehicle.

RESULTS

P-p38 protein levels and immunoreactivity were increased in stressed rats and colocalized with OX42-positive cells and neurons in the dorsal horn. This increase was reversed by minocycline or SB203580 exposure. Stress-induced increased NK1R expression was blocked by minocycline but not SB203580. WA-induced decreased IkappaBalpha expression was blocked by minocycline and SB203580. WA-induced hyperalgesia was blocked by minocycline and SB203580 intrathecally. Fractalkine-induced hyperalgesia was blocked by minocycline.

CONCLUSIONS

This is the first demonstration that stress-induced activation of spinal microglia has a key role in visceral hyperalgesia and associated spinal NK1R up-regulation.

Interstitial cystitis: bladder pain and beyond

BACKGROUND

Interstitial cystitis is characterized by over 6 months of chronic pain, pressure and discomfort felt in the lower pelvis or bladder. It is often relieved with voiding, along with daytime frequency and nocturia in the absence of a urinary tract infection. Interstitial cystitis occurs primarily in females including adolescents and its diagnosis is still one of exclusion. It is now recognized as a serious medical condition associated with significant disability.

OBJECTIVE

The aim of this paper was to review the pathogenesis and treatment of interstitial cystitis with emphasis on new pathogenetic trends and therapeutic modalities.

METHODS

About 713 mostly original papers were reviewed in Medline from 1990 to August. 2008. All authors independently reviewed the literature. Large, double-blind, placebo-controlled, clinical trials were few and the medical histories of the patients used varied considerably making conclusions difficult. Promising pilot trials turned out mostly negative on follow-up.

RESULTS

Increasing evidence of co-morbid diseases, neurogenic inflammation and the effect of stress are promising as new targets for pathophysiology. No new effective treatments have emerged. Oral pentosanpolysulfate, amitriptyline, hydroxyzine and quercetin, as well as intravesical heparin/bicarbonate/lidocaine solutions, are still used with variable success. Some pilot open-label trials presented encouraging findings.

CONCLUSION

Interstitial cystitis contributes substantially to chronic pelvic pain and to poor quality of life. Oral or intravesical administration of solutions containing sodium hyaluronate, chondroitin sulfate and quercetin to both reduce bladder inflammation and 'replenish' the glycosaminoglycan layer should be tried. There is a clear need for therapeutic modalities. New potential translational research areas are suggested.

Quercetin: further investigation of its antinociceptive properties and mechanisms of action

The antinociceptive action of quercetin, a common bioactive flavonoid present in many medicinal plants, was assessed in different models of chemical and thermal nociception in mice. Quercetin (10-60 mg/kg, i.p. or 100-500 mg/kg, p.o.) dose-dependently inhibited nociceptive behavior in the acetic acid-induced pain test. Moreover, quercetin (10-60 mg/kg, i.p.) inhibited both phases of formalin-induced pain, with ID50 values of 374.1 (68.0-402.0) mmol/kg and 103.0 (45.0-201.0) mmol/kg, for the neurogenic and inflammatory phases, respectively. Quercetin (10-60 mg/kg) also inhibited the nociception induced by glutamate and capsaicin by 68.2% and 75.5%, respectively. Its analgesic action was significantly reversed by p-chlorophenylalanine methyl ester, katanserin, methysergide, a GABA(A) antagonist (bicuculline), or a GABA(B) antagonists (baclofen). Its action was also modulated by tachykinins, but was not affected by adrenal-gland hormones. Furthermore, the antinociceptive effects did not result from muscle-relaxant or sedative action. Together, these results indicate that quercetin produces dose-related anti-nociception in several models of chemical pain, through mechanisms that involve interaction with L-arginine-nitric oxide, serotonin, and GABAergic systems. These results confirm and extend other investigations on the analgesic effect of quercetin and its mechanisms of action.

Type 4 phosphodiesterase inhibitor suppresses experimental bladder inflammation

OBJECTIVE

To evaluate the effects of orally administered YM976, a specific inhibitor of type 4 phosphodiesterase (PDE4), on bladder activity in a rat model with hydrochloric acid (HCl)-induced cystitis (IC), hypothesizing that a PDE4 inhibitor might suppress bladder overactivity and bladder pain responses in bladder-hypersensitive disorders such as IC.

MATERIALS AND METHODS

Wistar rats with HCl-induced IC were treated with YM976 or vehicle and their voiding observed and assessed by cystometry. The severity of bladder inflammation (BI) was quantified using the BI index (BII), which comprises three factors (oedema, leukocyte infiltration and haemorrhage). Nociceptive neural activity was also examined using an immunohistochemical study of spinal c-fos expression.

RESULTS

YM976 significantly reduced the number of voids, and the volume per void was significantly higher than in control (vehicle) group. Cystometry showed a significant increase in bladder capacity, voided volume and voiding efficiency, and a decrease in the amplitude of voiding pressure in rats treated with YM976. All BII scores were significantly lower in the YM976 than in the control group. c-fos expression in the spine was less in the YM976 than in the control group.

CONCLUSIONS

Oral administration of YM976 significantly improved the voiding behaviour and histological damage in rats with IC induced by HCl. These results indicate that PDE4 inhibitor might be effective in relieving bladder symptoms with IC.

The flavonoid quercetin regulates growth and gene expression in rat FRTL-5 thyroid cells

Quercetin is the most consumed flavonoid present in fruits and vegetables. There has been increased interest in the possible health benefits of quercetin and other flavonoids. Because it is reported that these compounds have some antithyroid properties, we were interested whether, and by what mechanism, quercetin might regulate thyroid cell growth and function. In this report we show that quercetin inhibits thyroid cell growth in association with inhibition of insulin-modulated phosphatidylinositol 3-kinase-Akt kinase activity. Furthermore, quercetin decreases TSH-modulated RNA levels of the thyroid-restricted gene sodium/iodide symporter (NIS). We associated down-regulation of NIS RNA levels with inhibition of iodide uptake at comparable quercetin concentrations and could show that the inhibitory effect of quercetin on NIS RNA levels and iodide uptake is reproduced by inhibitors of the phospholipase-A(2)/lipoxygenase pathway. The specific inhibitor of protein kinase A, H89, only partially inhibited TSH-increased NIS expression and did not reproduce the quercetin effect. The quercetin studies thus reveal that the phospholipase-A(2)/lipoxygenase pathway appears to play an important role in TSH regulation of NIS gene expression, whereas quercetin inhibition of growth appears to involve an effect on insulin/IGF-I-Akt signaling. The data raise the possibility that quercetin may be a novel disruptor of thyroid function, which has potential effects on, or use in, the therapy of thyroid diseases.