Intravesical glucidic capsaicin versus glucidic solvent in neurogenic detrusor overactivity: a double blind controlled randomized study

Mechanotransduction in the urothelium: ATP signalling and mechanoreceptors

The urothelium, which covers the inner surface of the bladder, is continuously exposed to a complex physical environment where it is stimulated by, and responds to, a wide range of mechanical cues. Mechanically activated ion channels endow the urothelium with functioning in the conversion of mechanical stimuli into biochemical events that influence the surface of the urothelium itself as well as suburothelial tissues, including afferent nerve fibres, interstitial cells of Cajal and detrusor smooth muscle cells, to ensure normal urinary function during the cycle of filling and voiding. However, under prolonged and abnormal loading conditions, the urothelial sensory system can become maladaptive, leading to the development of bladder dysfunction. In this review, we summarize developments in the understanding of urothelial mechanotransduction from two perspectives: first, with regard to the functions of urothelial mechanotransduction, particularly stretch-mediated ATP signalling and the regulation of urothelial surface area; and secondly, with regard to the mechanoreceptors present in the urothelium, primarily transient receptor potential channels and mechanosensitive Piezo channels, and the potential pathophysiological role of these channels in the bladder. A more thorough understanding of urothelial mechanotransduction function may inspire the development of new therapeutic strategies for lower urinary tract diseases.

Efficacy of overactive neurogenic bladder treatment: A systematic review of randomized controlled trials

BACKGROUND

Overactive bladder (OAB) symptoms of frequency, urgency and urge incontinence are frequently associated with known neurological diseases like multiple sclerosis (MS), spinal cord injury (SCI), Parkinson's disease (PD), stroke.

OBJECTIVE

The aim of our study was to review the efficacy of pharmacological and non-pharmacological treatments for neurogenic overactive bladder.

MATERIALS AND METHODS

We searched two electronic databases (PubMed and EMBASE) for randomized controlled trials focusing on pharmacological and non-pharmacological medical treatments for overactive bladder symptoms associated with neurological diseases published up to 30 April 2022.

RESULTS

A total of 157 articles were retrieved; 94 were selected by title and abstract screening; after removal of 17 duplicates, 77 records were evaluated by full-text examination. Sixty-two studies were finally selected. The articles selected for review focused on the following interventions: anticholinergics (n = 9), mirabegron (n = 5), comparison of different drugs (n = 3), cannabinoids (n = 2), intravesical instillations (n = 3), botulinum toxin (n = 16), transcutaneous tibial nerve stimulation (TTNS) (n = 6), acupuncture (n = 2), transcutaneous electrical nerve stimulation TENS (n = 4), pelvic floor muscle training (PFMT) (n = 10), others (n = 2). Anticholinergics were more effective than placebo in decreasing the number of daily voids in patients with PD (mean difference [MD]- 1.16, 95 % CI - 1.80 to - 0.52, 2 trials, 86 patients, p < 0.004), but no significant difference from baseline was found for incontinence episodes and nocturia. Mirabegron was more effective than placebo in increasing the cystometric capacity in patients with MS (mean difference [MD] 89.89 mL, 95 % CI 29.76 to 150.01, 2 trials, 98 patients, p < 0.003) but no significant difference was observed for symptom scores and bladder diary parameters. TTNS was more effective than its sham-control in decreasing the number of nocturia episodes (MD -1.40, 95 % CI -2.39 to -0.42, 2 trials, 53 patients, p < 0.005) but no significant changes of OAB symptom scores were reported. PFMT was more effective than conservative advice in decreasing the ICIQ symptom score (MD, -1.12, 95 % CI -2.13 to -0.11, 2 trials, 91 patients, p = 0.03), although the number of incontinence episodes was not significantly different between groups.

CONCLUSIONS

The results of the meta-analysis demonstrate a moderate efficacy of all considered treatments without proving the superiority of one therapy over the others. Combination treatment using different pharmacological and non-pharmacological therapies could achieve the best clinical efficacy due to the favorable combination of the different mechanisms of action. This could be associated with fewer side effects due to drug dosage reduction. These data are only provisional and should be considered with caution, due to the few studies included in metaanalysis and to the small number of patients.

Investigational Drug Therapies for Overactive Bladder Syndrome: The Potential Alternatives to Anticolinergics

Background

Overactive bladder is a high prevalent and quality of life affecting disease. The mainstay of the medical therapy is represented by antimuscarinic drugs, but their side effects markedly affect patient compliance and prompt studies on novel investigational drugs.

Methods

A systematic literature search of peer-reviewed papers and meeting abstracts published by December 2008 was performed. PubMed databank was searched for original English articles, by using the following search terms: “overactive bladder” or “detrusor overactivity” or “urinary incontinence” and “treatment”, alone and linked to any potential molecular target or novel drug cited in the literature.

Results

Effective alternative pharmacological treatments are currently scarce, but many new promising compounds are emerging which target key molecular pathways involved in micturition control. The most promising potential therapeutic targets include central nervous system GABAergic inhibitory pathway, dopaminergic and serotoninergic systems, b-adrenoceptors and cAMP metabolism, nonadrenergic-noncholinergic mechanisms such as purinergic and neuropeptidergic systems, vanilloid receptor, bladder sensory nervous terminals, nonneuronal bladder signalling systems including urothelium and interstitial cells, prostanoids, Rho-kinase and different subtypes of potassium and calcium channels.

Conclusions

Despite the enormous amount of new biologic insight, very few novel pharmacological therapies seems to have passed the proof-of-concept clinical stage. The ultimate clinical utility of new drugs will depend on the ability to exploit tissue-specific differences and disease-related changes in molecular expression/function and to improve storage phase dysfunctions without interfering with the emptying phase. Further preclinical investigations and controlled clinical trials are urgently needed in this challenging field.

Intravesical vanilloids for treating neurogenic lower urinary tract dysfunction in patients with multiple sclerosis: A systematic review and meta-analysis. A report from the Neuro-Urology Promotion Committee of the International Continence Society (ICS)

AIMS

To systematically assess all available evidence on efficacy and safety of vanilloids for treating neurogenic lower urinary tract dysfunction (NLUTD) in patients with multiple sclerosis (MS).

METHODS

This systematic review and meta-analysis was performed according to the Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) statement. Studies were identified by electronic search of Cochrane register, Embase, Medline, Scopus, (last search January 8, 2016).

RESULTS

After screening of 7848 abstracts, 4 randomized controlled trials (RCTs) and 3 prospective cohort studies were included. Pooled data from three RCTs evaluating intravesical capsaicin showed the standardized mean difference to be -2.16 (95% confidence interval [CI] -2.87 to -1.45) in incontinence episodes per 24 h and -0.54 (95%CI -1.03 to -0.05) in voids per 24 h. There was no statistically significant effect on maximum cystometric capacity and maximum storage detrusor pressure. Overall, adverse events were reported by >50% of the patients, most commonly were pelvic pain, facial flush, worsening of incontinence, autonomic dysreflexia, urinary tract infection and haematuria. Risk of bias and confounding was relevant in both RCTs and non-RCTs.

CONCLUSIONS

Preliminary data suggest that intravesical vanilloids might be effective for treating NLUTD in patients with MS. However, the safety profile seems unfavorable, the overall quality of evidence is low and no licensed substance is currently available warranting well-designed, adequately sampled and properly powered RCTs.

Capsaicin: Current Understanding of Its Mechanisms and Therapy of Pain and Other Pre-Clinical and Clinical Uses

In this review, we discuss the importance of capsaicin to the current understanding of neuronal modulation of pain and explore the mechanisms of capsaicin-induced pain. We will focus on the analgesic effects of capsaicin and its clinical applicability in treating pain. Furthermore, we will draw attention to the rationale for other clinical therapeutic uses and implications of capsaicin in diseases such as obesity, diabetes, cardiovascular conditions, cancer, airway diseases, itch, gastric, and urological disorders.

Pioneering drugs for overactive bladder and detrusor overactivity: Ongoing research and future directions

The ongoing research on pioneering drug candidates for the overactive bladder (OAB) aimed to overcome the limitations of currently licensed pharmacotherapies, such as antimuscarinics, β3-adrenergic agents, and botulinum neurotoxin, has been reviewed performing a systematic literature review and web search. The review covers the exploratory agents alternative to available medications for OAB and that may ultimately prove to be therapeutically useful in the future management of OAB patients based on preclinical and early clinical data. It emerges that many alternative pharmacological strategies have been discovered or are under investigation in disease-oriented studies. Several potential therapeutics are known for years but still find obstacles to pass the clinical stages of development, while other completely novel compounds, targeting new pharmacological targets, have been recently discovered and show potential to translate into clinical therapeutic agents for idiopathic and neurogenic OAB syndrome. The global scenario of investigational drugs for OAB gives promise for the development of innovative therapeutics that may ultimately prove effective as first, combined or second-line treatments within a realistic timescale of ten years.

[Multiple sclerosis and pelviperineology: Urinary and sexual dysfunctions and pregnancy]

GOAL

The aim was to review the literature on genito-urinary dysfunction in multiple sclerosis (MS).

MATERIAL

A literature review through the PubMed library until August, 31 2013 was carried out using the following keywords: multiple sclerosis and neurogenic bladder, neuropathic bladder, bladder, management, follow-up, urological complications, urological treatment, sexual dysfunction, female sexual function, male sexual function, erectile dysfunction, anorectal, faecal, constipation, bowel, pregnancy, parturition, delivery, breast-feeding.

RESULTS

Genito-urinary dysfunction is frequent in MS (35-90%) and may happen soon in the disease. Urinary symptoms (10-90%) are manifold resulting in a quality of life alteration and the onset of complications in 30% of the cases requiring a long-term follow-up. Sexual dysfunctions (35-87%) are also manifold affecting all the sexuality domains in men and women. Except the phosphodiesterase V inhibitors, few treatments have been assessed in this population. Pregnancy is nowadays considered as beneficial resulting in a disease slow-down and the lack of disease worsening despite an increase in disease relapse during the post-partum first quarter. It seems to be better to consider getting pregnant after at least one year without any relapse and to emphasize an exclusive breast-feeding.

CONCLUSION

Urinary and sexual dysfunctions are frequent in MS. A transdisciplinary approach including the neurologist and pelviperineology specialists facilitates a disability adapted early management.

Modulation of urinary bladder innervation: TRPV1 and botulinum toxin A

The persisting interest around neurotoxins such as vanilloids and botulinum toxin (BoNT) derives from their marked effect on detrusor overactivity refractory to conventional antimuscarinic treatments. In addition, both are administered by intravesical route. This offers three potential advantages. First, intravesical therapy is an easy way to provide high concentrations of pharmacological agents in the bladder tissue without causing unsuitable levels in other organs. Second, drugs effective on the bladder, but inappropriate for systemic administration, can be safely used as it is the case of vanilloids and BoNT. Third, the effects of one single treatment might be extremely longlasting, contributing to render these therapies highly attractive to patients despite the fact that the reasons to the prolonged effect are still incompletely understood. Attractive as it may be, intravesical pharmacological therapy should still be considered as a second-line treatment in patients refractory to conventional oral antimuscarinic therapy or who do not tolerate its systemic side effects. However, the increasing off-label use of these neurotoxins justifies a reappraisal of their pharmacological properties.

Emerging pharmacological targets in overactive bladder therapy: experimental and clinical evidences

Antimuscarinics are the mainstay of the medical therapy for overactive bladder, but their side effects and often modest success have prompted studies on novel pharmacological approaches. In this paper, we give a systematic literature review of peer-reviewed papers on the subject. Effective nonantimuscarinic treatments are currently scarce, but many new promising compounds are emerging, which target key molecular pathways involved in micturition control. The most promising potential therapeutic targets include: nervous GABAergic, glycinergic, dopaminergic, and serotonergic systems; b-adrenoceptors and cAMP metabolism; nonadrenergic-noncholinergic mechanisms such as purinergic and neuropeptidergic systems; vanilloid receptors; bladder afferent nerves; nonneuronal bladder signaling systems including urothelium and interstitial cells; prostanoids; Rho-kinase; and different subtypes of potassium and calcium channels. Despite the enormous amount of new biologic insight, very few drugs with mechanism of action other than antimuscarinics have passed as yet the proof-of-concept stage. Further preclinical and clinical studies are urgently needed in this rapidly moving field.

Neurotoxin treatments for urinary incontinence in subjects with spinal cord injury or multiple sclerosis: a systematic review of effectiveness and adverse effects

BACKGROUND/OBJECTIVE

The objective was to evaluate the effectiveness of neurotoxin treatments of urinary incontinence (UI) in individuals with spinal cord injury (SCI) or multiple sclerosis (MS).

METHODS

Studies were included if published in English, presented randomized adults with SCI or MS, and reported UI outcomes.

RESULTS

Ten trials randomizing 288 subjects with SCI (43%), MS (52%), or other spinal conditions (5%) and UI refractory to oral antimuscarinics were included. The overall mean age was 41 years, and 46% were women. Study durations ranged from 1 to 18 months. Treatments included botulinum toxin-A (BTX-A, 2 trials) and 2 vanilloid compounds, capsaicin (6 trials) and resiniferatoxin (4 trials). BTX-A was superior to placebo and resiniferatoxin in reducing daily UI episodes, mainly in individuals with SCI, although significant reductions vs placebo were not evident throughout the study duration. There were 1.1 fewer daily UI episodes in the BTX-A 200 unit group vs 0.1 fewer for the placebo group at the final week 24 assessment. Capsaicin was generally superior to placebo. The weighted difference between capsaicin and placebo in a pooled analysis of 2 trials enrolling subjects with either paraplegia or tetraplegia (n = 32) was -3.8 daily UI episodes [95% Cl -4.7 to -2.9] after 30 days. Capsaicin was comparable to resiniferatoxin. Pelvic pain and facial flushing were associated with capsaicin.

CONCLUSION

Neurotoxins may improve refractive UI in adults with SCI or MS, although trial results were inconsistent. Trials were small in size and relatively short in duration. Further studies are needed to determine the efficacy and tolerability of long-term application.

On the origin of bladder sensing: Tr(i)ps in urology

The mammalian TRP family consists of 28 channels that can be subdivided into 6 different classes: TRPV (vanilloid), TRPC (canonical), TRPM (Melastatin), TRPP (Polycystin), TRPML (Mucolipin), and TRPA (Ankyrin). TRP channels are activated by a diversity of physical (voltage, heat, cold, mechanical stress) or chemical (pH, osmolality) stimuli and by binding of specific ligands, enabling them to act as multifunctional sensors at the cellular level. Currently, a lot of scientific research is devoted to these channels and their role in sensing mechanisms throughout the body. In urology, there's a growing conviction that disturbances in afferent (sensory) mechanisms are highly important in the pathogenesis of functional problems. Therefore, the TRP family forms an interesting new target to focus on. In this review we attempt to summarize the existing knowledge about TRP channels in the urogenital tract. So far, TRPV1, TRPV2, TRPV4, TRPM8, and TRPA1 have been described in different parts of the urogenital tract. Although only TRPV1 (the vanilloid receptor) has been extensively studied so far, more evidence is slowly accumulating about the role of other TRP channels in the (patho)physiology of the urogenital tract.

Chapitre C-l A - Traitement pharmacologique de l’hyperactivité détrusorienne neurologique : per os, en patch, en instillation endo-vésicale

Functional rehabilitation of neurourological patients always starts with patient education, retraining, and occupational therapy, possibly completed by medical treatments. In the light of a systematic review of the literature, the authors describe the various treatments that can be used orally and by intravesical instillation in these patients. They also describe treatments such as desmopressin or agents that increase sphincter pressure, which can sometimes be very useful to obtain stable clinical results that are satisfactory for the patient.