Does irritable bowel syndrome increase the risk of interstitial cystitis/bladder pain syndrome? A cohort study of long term follow-up

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.

Association Between Irritable Bowel Syndrome and Lower Urinary Tract Symptomatology: A Cross-sectional Study in Mexican Population

GOALS

This study aimed to investigate the clinical phenotype of urinary symptoms in patients diagnosed with irritable bowel syndrome, the factors associated with this overlap, and the impact of urinary symptoms on their quality of life.

BACKGROUND

Irritable bowel syndrome is a common disorder, affecting up to 3.8% of the population. The overlap with other disorders of the gut-brain interaction, psychiatric disorders, and other somatic disorders is common. Moreover, the association between irritable bowel syndrome and urinary symptoms has been recognized, but the clinical phenotype remains unclear.

STUDY

This cross-sectional study involved patients with irritable bowel syndrome according to Rome IV. Lower urinary tract symptoms were classified using the International Continence Society's classification. Data on demographics, medical history, medication use, anxiety, depression, and quality of life were collected and analyzed using logistic regression analysis.

RESULTS

The study included 428 subjects, 86 diagnosed with irritable bowel syndrome. Patients exhibited a higher prevalence of lower urinary tract symptoms (60.5%, 95% CI: 50.5-71.9). Multivariate analysis revealed associations between irritable bowel syndrome and lower urinary tract symptoms (OR: 2.49, 95% CI: 1.48-4.18, P=0.001), particularly storage urinary symptoms (OR: 1.94, 95% CI: 1.10-3.40, P=0.021). Patients with urinary symptoms reported significantly lower quality of life compared with those without these symptoms (50.8±17.2 vs. 76.7±21.8, P<0.001).

CONCLUSIONS

Irritable bowel syndrome is associated with lower urinary tract symptoms, contributing to a significant reduction in quality of life. Clinicians should consider referring patients with irritable bowel syndrome and lower urinary tract symptoms to experts in urodynamics to provide targeted management.

Animal models of interstitial cystitis/bladder pain syndrome

Interstitial Cystitis/Bladder Pain Syndrome (IC/BPS) is a chronic disorder characterized by pelvic and/or bladder pain, along with lower urinary tract symptoms that have a significant impact on an individual's quality of life. The diverse range of symptoms and underlying causes in IC/BPS patients pose a significant challenge for effective disease management and the development of new and effective treatments. To facilitate the development of innovative therapies for IC/BPS, numerous preclinical animal models have been developed, each focusing on distinct pathophysiological components such as localized urothelial permeability or inflammation, psychological stress, autoimmunity, and central sensitization. However, since the precise etiopathophysiology of IC/BPS remains undefined, these animal models have primarily aimed to replicate the key clinical symptoms of bladder hypersensitivity and pain to enhance the translatability of potential therapeutics. Several animal models have now been characterized to mimic the major symptoms of IC/BPS, and significant progress has been made in refining these models to induce chronic symptomatology that more closely resembles the IC/BPS phenotype. Nevertheless, it's important to note that no single model can fully replicate all aspects of the human disease. When selecting an appropriate model for preclinical therapeutic evaluation, consideration must be given to the specific pathology believed to underlie the development of IC/BPS symptoms in a particular patient group, as well as the type and severity of the model, its duration, and the proposed intervention's mechanism of action. Therefore, it is likely that different models will continue to be necessary for preclinical drug development, depending on the unique etiology of IC/BPS being investigated.

Irritable bowel syndrome - controversies in diagnosis and management

INTRODUCTION

The irritable bowel syndrome (IBS) is the best-recognized disorder of gut brain interactions (DGBI). However, it is controversial if the Rome IV criteria iteration for IBS diagnosis is fit for purpose.

AREAS COVERED

This review critically evaluates Rome IV criteria for diagnosis of IBS and addresses clinical considerations in IBS treatment and management, including dietary factors, biomarkers, disease mimics, symptom severity, and subtypes. The role of diet in IBS is critically reviewed along with the influence of the microbiota, including small intestinal bacterial overgrowth.

EXPERT OPINION

Emerging data suggest the Rome IV criteria are more suitable for identifying severe IBS and least useful for sub-diagnostic patients who are still likely to benefit from IBS treatment. Despite convincing evidence that IBS symptoms are diet-driven and often postprandial, a relationship to eating is not a Rome IV diagnostic criterion. Few IBS biomarkers have been identified, suggesting the syndrome is too heterogeneous to be measured by a single marker, and combined biomarker, clinical, dietary, and microbial profiling may be needed for objective characterization. With many organic diseases mimicking and overlapping with IBS, it's important clinicians are knowledgable about this to mitigate the risk of missing comorbid organic intestinal disease and to optimally treat IBS symptoms.

Therapeutic effects of paeoniflorin on irritable bowel syndrome in rats

BACKGROUND

Irritable bowel syndrome (IBS) is a functional bowel disorder (FBD).

OBJECTIVES

To assess the therapeutic effects of paeoniflorin (PF) on IBS in rats.

METHOD

Sixty male Sprague-Dawley rats were randomly divided into normal, model, positive drug, low-dose PF, medium-dose PF and high-dose PF groups (n = 10). After gavage for 2 consecutive weeks, the effect of PF on abdominal pain symptoms was assessed based on the abdominal withdrawal reflex (AWR) score, fecal water content and pathological changes in colon tissues. D-lactate, interleukin-1β (IL-1β), transforming growth factor-β (TGF-β) and tumor necrosis factor-α (TNF-α) were detected by enzyme-linked immunosorbent assay, and phosphorylated nuclear factor kappa B (p-NF-κB) p65 was detected by Western blotting. The abundance and diversity changes of intestinal flora were explored using 16S ribosomal RNA sequencing.

RESULT

In PF groups, the mucosal morphology of colon tissues was intact, and the glands were arranged neatly and structured clearly, without obvious inflammatory cell infiltration. Compared with the model group, PF groups had significantly elevated pain threshold, and mRNA and protein levels of zonula occludens-1 (ZO-1) and occludin, decreased AWR score at 20 mmHg pressure, fecal water content, mRNA levels of IL-1β, TGF-β, and TNF-α, protein level of p-NF-κB p65 and level of serum D-lactate, and reduced levels of serum IL-1β, TGF-β, and TNF-α (p < 0.05, p < 0.01). PF groups had higher abundance of Lactobacillus, Akkermansia, Alistipes, and Bacteroides, but lower abundance of Desulfovibrio, Parasutterella, and Enterococcus than those of the model group.

CONCLUSIONS

PF exerts therapeutic effects on IBS in rats probably by regulating the intestinal flora, and then up-regulating the expressions of ZO-1 and occludin in colon tissue while down-regulating the levels of IL-1β, TGF-β, TNF-α, D-lactate and p-NF-κB p65.

Fatty Acid Amide Hydrolase: An Integrative Clinical Perspective

Introduction: Fatty acid amide hydrolase (FAAH) is one of the main terminating enzymes of the endocannabinoid system (ECS). Since being discovered in 1996, the modulation of FAAH has been viewed as a compelling alternative strategy to obtain the beneficial effect of the ECS. With a considerable amount of FAAH-related publication over time, the next step would be to comprehend the proximity of this evidence for clinical application. Objective: This review intends to highlight the rationale of FAAH modulation and provide the latest evidence from clinical studies. Methods: Publication searches were conducted to gather information focused on FAAH-related clinical evidence with an extension to the experimental research to understand the biological plausibility. The subtopics were selected to be multidisciplinary to offer more perspective on the current state of the arts. Discussion: Experimental and clinical studies have demonstrated that FAAH was highly expressed not only in the central nervous system but also in the peripheral tissues. As the key regulator of endocannabinoid signaling, it would appear that FAAH plays a role in the modulation of mood and emotional response, reward system, pain perception, energy metabolism and appetite regulation, inflammation, and other biological processes. Genetic variants may be associated with some conditions such as substance/alcohol use disorders, obesity, and eating disorder. The advancement of functional neuroimaging has enabled the evaluation of the neurochemistry of FAAH in brain tissues and this can be incorporated into clinical trials. Intriguingly, the application of FAAH inhibitors in clinical trials seems to provide less striking results in comparison with the animal models, although some potential still can be seen. Conclusion: Modulation of FAAH has an immense potential to be a new therapeutic candidate for several disorders. Further exploration, however, is still needed to ensure who is the best candidate for the treatment strategy.

Overlaps with bladder pain syndrome and irritable bowel syndrome are associated with higher symptom burden and reduced quality of life in functional dyspepsia

BACKGROUND

Functional dyspepsia and bladder pain syndrome are well-known to overlap with irritable bowel syndrome. Whether functional dyspepsia overlaps with bladder pain syndrome remains unknown. Our aim was to evaluate the presence of bladder pain syndrome in functional dyspepsia patients and its impact.

METHODS

All consecutive patients with investigated dyspeptic symptoms in our tertiary care center between March 2015 and November 2018 were studied. Functional dyspepsia and irritable bowel syndrome were diagnosed according to Rome III and IV criteria while bladder pain syndrome was diagnosed using ESSIC criteria. Validated questionnaires were filled to assess quality of life (GIQLI), anxiety and depression (HADS), sleep (PSQI), and insomnia (ISI). Dyspeptic symptoms severity was assessed individually for eight dyspeptic complaints.

KEY RESULTS

Among 1453 patients with dyspeptic symptoms, 61.4% fulfilled Rome criteria for functional dyspepsia. Bladder pain syndrome was present in 16.0% of the patients not fulfilling diagnostic criteria for functional dyspepsia, 22.2% of patients with functional dyspepsia alone, and 36.4% of patients with overlapping functional dyspepsia and irritable bowel syndrome (p-values &lt;0.0001). In patients with bladder pain syndrome overlapping with functional dyspepsia, dyspeptic symptoms severity, anxiety, depression, and insomnia levels were higher while quality of life and sleep quality were reduced (p-values &lt;0.0001). These results were even more pronounced in case of overlap with irritable bowel syndrome (p-values &lt;0.0001).

CONCLUSIONS AND INFERENCES

Bladder pain syndrome is present in 26.9% of functional dyspepsia patients and is associated with higher gastrointestinal, psychological distresses, and sleep symptom burdens, and with reduced quality of life.

Inhibition of CXCR4 in Spinal Cord and DRG with AMD3100 Attenuates Colon-Bladder Cross-Organ Sensitization

Background

Cross-sensitization of pelvic organs is one theory for why symptoms of gut sickness and interstitial cystitis/bladder pain syndrome overlap. Experimental colitis has been shown to trigger bladder hyperactivity and hyperalgesia in rats. The chemokine receptor CXCR4 plays a key role in bladder function and central sensitization. We aim to study the role of CXCR4 and its inhibitor AMD3100 in colon-bladder cross-organ sensitization.

Methods

The colitis model was established by rectal infusion of trinitrobenzene sulfonic acid. Western blot and immunofluorescence were used to assess the expression and distribution of CXCR4. Intrathecal injection of AMD3100 (a CXCR4 inhibitor) and PD98059 (an ERK inhibitor) were used to inhibit CXCR4 and downstream extracellular signal-regulated kinase (ERK) in the spinal cord and dorsal root ganglion (DRG). Intravesical perfusion of resiniferatoxin was performed to measure the pain behavior counts of rats, and continuous cystometry was performed to evaluate bladder voiding function.

Results

Compared to the control group, CXCR4 was expressed more in bladder mucosa and colon mucosa, L6-S1 dorsal root ganglion (DRG), and the corresponding segment of the spinal dorsal horn (SDH) in rats with colitis. Moreover, intrathecal injection of the AMD3100 suppressed bladder overactivity, bladder hyperalgesia, and mastocytosis symptoms caused by colitis. Furthermore, AMD3100 effectively inhibited ERK activation in the spinal cord induced by experimental colitis. Finally, treatment with PD98059 alleviated bladder overactivity and hyperalgesia caused by colitis.

Conclusion

Increased CXCR4 in the DRG and SDH contributes to colon inflammation-induced bladder overactivity and hyperalgesia partly via the phosphorylation of spinal ERK. Treatment targeting the CXCR4/ERK pathway might provide a potential new approach for the comorbidity between the digestive system and the urinary system.

Review article: Physical and psychological comorbidities associated with irritable bowel syndrome

Irritable bowel syndrome (IBS) is one of the most common gastrointestinal disorders encountered by physicians in primary and secondary care. Patients with IBS commonly present with various extraintestinal complaints, which account for a substantial clinical and economic burden. The common extraintestinal comorbidities associated with IBS include anxiety, depression, somatisation, fibromyalgia, chronic fatigue syndrome, chronic pelvic pain, interstitial cystitis, sexual dysfunction and sleep disturbance. The presence of comorbidity in IBS poses a diagnostic and therapeutic challenge with patients frequently undergoing unnecessary investigations and interventions, including surgery. This review discusses the different physical and psychological comorbidities associated with IBS, the shared pathophysiological mechanisms and potential management strategies.