Low Energy Shock Wave Therapy Inhibits Inflammatory Molecules and Suppresses Prostatic Pain and Hypersensitivity in a Capsaicin Induced Prostatitis Model in Rats.

The effect of low energy shock wave (LESW) therapy on the changes of inflammatory molecules and pain reaction was studied in a capsaicin (10 mM, 0.1 cc) induced prostatitis model in rats. Intraprostatic capsaicin injection induced a pain reaction, including closing of the eyes, hypolocomotion, and tactile allodynia, which effects were ameliorated by LESW treatment. LESW therapy (2Hz, energy flux density of 0.12 mJ/mm2) at 200 and 300 shocks significantly decreased capsaicin-induced inflammatory reactions, reflected by a reduction of tissue edema and inflammatory cells, COX-2 and TNF-α stained positive cells, however, the therapeutic effects were not observed at 100 shocks treated group. Capsaicin-induced IL-1ß, COX-2, IL-6, caspase-1, and NGF upregulation on day 3 and 7, while NALP1 and TNF-α upregulation was observed on day 7. LESW significantly suppressed the expression of IL-1ß, COX-2, caspase-1, NGF on day 3 and IL-1ß, TNF-α, COX-2, NALP1, caspase-1, NGF expression on day 7 in a dose-dependent fashion. LESW has no significant effect on IL-6 expression. Intraprostatic capsaicin injection activates inflammatory molecules and induces prostatic pain and hypersensitivity, which effects were suppressed by LESW. These findings might be the potential mechanisms of LESW therapy for nonbacterial prostatitis in humans.

Liposome Based Intravesical Therapy Targeting Nerve Growth Factor Ameliorates Bladder Hypersensitivity in Rats with Experimental Colitis.

PURPOSE: Pelvic organ cross sensitization is considered to contribute to overlapping symptoms in chronic pelvic pain syndrome. Nerve growth factor over expression in the bladder is reportedly involved in the symptom development of bladder pain syndrome/interstitial cystitis. We examined whether a reduction of over expressed nerve growth factor in the bladder by intravesical treatment with liposome and oligonucleotide conjugates would ameliorate bladder hypersensitivity in a rat colitis model. MATERIALS AND METHODS: Adult female rats were divided into 1) a control group, 2) a colitis-oligonucleotide group with intracolonic TNBS (2,4,6-trinitrobenzene sulfonic acid) enema and intravesical liposome-oligonucleotide treatments, 2) a colitis-saline group with intracolonic TNBS and intravesical saline treatments, 4) a sham oligonucleotide group with intravesical liposome-oligonucleotide treatment without colitis and 5) a sham-saline group with intravesical saline treatment without colitis. Liposomes conjugated with nerve growth factor antisense oligonucleotide or saline solution were instilled in the bladder and 24 hours later colitis was induced by TNBS enema. Effects of nerve growth factor antisense treatment were evaluated by pain behavior, cystometry, molecular analyses and immunohistochemistry 10 days after TNBS treatment. RESULTS: In colitis-oligonucleotide rats nerve growth factor antisense treatment ameliorated pain behavior and decreased a reduction in the intercontraction interval in response to acetic acid stimulation as well as nerve growth factor expression in the bladder mucosa. All were enhanced in colitis-saline rats compared to sham rats. CONCLUSIONS: Nerve growth factor over expression in the bladder mucosa and bladder hypersensitivity induced after colitis were decreased by intravesical application of liposome-oligonucleotide targeting nerve growth factor. This suggests that local antinerve growth factor therapy could be effective treatment of bladder symptoms in chronic pelvic pain syndrome.

Effect of Sacral Neuromodulation on Outcome Measures and Urine Chemokines in Interstitial Cystitis/Painful Bladder Syndrome Patients.

OBJECTIVES: Sacral neuromodulation (SNM) may improve interstitial cystitis/painful bladder syndrome (IC/BPS) symptoms of urinary frequency, urgency and perhaps even pain, but objective measures of improvement are lacking. We evaluated the potential for urinary chemokines to serve as measures of treatment response over time to SNM. METHODS: Women with IC/BPS undergoing SNM consented for this study. Three-day bladder/pain diaries were collected at baseline and validated Interstitial Cystitis Symptom Problem Index (ICSPI) scores and mid-stream urine specimens were collected at baseline and at 24 weeks after successful implant. Collected urine was screened for infection by dipstick and analyzed for chemokines by luminex xMAP analysis. RESULTS: At baseline (n = 16), urine levels of CXCL-1 positively correlated with pain score (r = 0.63, P = 0.009), urgency (r = 0.61, P = 0.01), ICSPI (r = 0.43, P = 0.09) and daily voids (r = 0.44, P = 0.08). ICSPI and pain scores also positively correlated with sIL-1ra (r = 0.50, P = 0.04) and monocyte chemotactic protein-1 (MCP-1) or CCL2 positively correlated with daily voids (r = 0.45, P = 0.07) only. At 24 weeks, the median ICSPI index fell from 28 to 15 (n = 7, P = 0.008). Urine levels of sIL-1ra (633.8 ± 188.2 vs. 149.9 ± 41.62 pg/mL) and MCP-1 (448.3 ± 11.6 vs. 176.9 ± 46.16 pg/mL) and CCL5 (20.78 ± 4.09 vs. 11.21 ± 4.12 pg/mL) were also significantly reduced at the follow-up relative to baseline values (P = 0.04). Multivariable analysis of data revealed that sIL-1ra and MCP-1 together explained the majority of variance in data. Levels of CXCL-1, CXCL-10, interleukin (IL)-8, vascular endothelial growth factor (VEGF), platelet-derived growth factor (PDGF) were also reduced at 24 weeks, but differences were not significant. CONCLUSIONS: Concomitant decrease in urine levels of chemokines especially MCP-1 was associated with treatment response of SNM. These results support the role of chemokines as downstream effectors of neuromodulation response and could serve as potential non-invasive measures of treatment response. CLINICAL TRIAL REGISTRATION NUMBER: NCT01739946.

Advanced therapeutic directions to treat the underactive bladder.

Muscarinic agonists are the most commonly used agents for treating the underactive bladder (UAB). However, because of the absence of pharmacologic specificity for bladder-only effects and possibly as a result of degenerative and other post-synaptic changes involving detrusor smooth muscle cells, they are simply not effective and side effects are common. If safe and effective therapy for UAB is made available, then most experts agree that the potential market would exceed industry expectations, just as antimuscarinic agents for overactive bladder did in the late 1990 s. The pharmaceutical and biotechnology industries that have a pipeline to urology and women's health should consider UAB as a potential target condition. A rational approach to treating the pathology of UAB is presented with a discussion of potential targets that may allow the development of safe and effective agents for the treatment of UAB.

The pharmacokinetic evaluation of mirabegron as an overactive bladder therapy option.

INTRODUCTION: Mirabegron is a new once-daily, oral treatment for management of overactive bladder (OAB) that is approved in USA, EU and Japan. It activates ß3 adrenoceptor to facilitate bladder filling and reduce mean micturition frequency with better safety profile than current treatment of antimuscarinic drugs. AREAS COVERED: The following article reviews the information available from published randomized trials on the metabolism and pharmacokinetics mirabegron. The reader will gain better insight into the variability in plasma exposure of mirabegron due to various causes. Propensity for drug interactions with mirabegron is low as its clearance involves multiple metabolic and excretory pathways. Mirabegron is generally well tolerated, but its pharmacokinetics is altered by dose and gender with implications for cardiovascular toxicity. EXPERT OPINION: Mirabegron is a first-in-class of ß3 adrenoceptor agonists that could offer an alternative to antimuscarinics for OAB patients. The marketed dose of 50 mg achieves primary efficacy endpoints but causes only modest improvement over placebo in terms of daily incontinence and voiding episodes. Involvement of saturable efflux transporters is indicated in oral bioavailability of mirabegron. It is well tolerated with hypertension, nasopharyngitis, urinary tract infection and headache being the most common side effects.

Mirabegron, a ß3-adrenoceptor agonist for the potential treatment of urinary frequency, urinary incontinence or urgency associated with overactive bladder.

Mirabegron (YM-178), currently in development by Astellas Pharma Inc, is an orally active ß3-adrenoceptor (AR) agonist for the potential symptomatic treatment of overactive bladder (OAB). Mirabegron demonstrates nanomolar EC50 values against the human ß3-AR in biochemical assays with potent selectivity over the ß1- and ß2-ARs. Originally developed as a treatment for diabetes, the development of mirabegron was later refocused to OAB. Cystometric experiments in rats reported a reduction in resting intravesical pressure and contraction frequency in anesthetized rats, without any effect on the amplitude of micturition contraction. Mirabegron also reduced non-micturition bladder contractions in an awake rat model of bladder outlet obstruction. Top-line results from clinical trials to date indicate that mirabegron has been well tolerated with significant efficacy in reducing the number of incontinence episodes and mean micturition frequency in patients. Evidence of cytochrome P450 (CYP)2D6 inhibition in clinical trials highlighted a concern for pharmacokinetic interaction with other drugs that are CYP2D6 substrates, as confirmed by a rise in the pharmacokinetic parameters of desipramine with concomitant administration of mirabegron. Mirabegron exhibits a novel mode of action in targeting the ß3-AR for bladder relaxation, and the studies and trials conducted to date suggest mirabegron as a promising new treatment in the management of OAB symptoms, such as increased urinary urgency and frequency, and urgency incontinence.

Instillation of liposomes vs dimethyl sulphoxide or pentosan polysulphate for reducing bladder hyperactivity.

OBJECTIVE: To investigate the efficacy of intravesical liposomes against dimethyl sulphoxide (DMSO), and pentosan polysulphate (PPS) in reducing chemically induced bladder hyperactivity in rats. MATERIALS AND METHODS: Bladder reflex activity of female Sprague-Dawley rats was evaluated by continuous cystometry under urethane anaesthesia (1.0 g/kg). After obtaining a control cystometrogram (CMG) with normal saline (0.04 mL/min) for 2 h, bladder hyperactivity was then induced by 1 h infusion of protamine sulphate (10 mg/mL) followed by a 1-h infusion of KCl (500 mm). Six rats each were then infused with KCl-based preparations containing either 50% DMSO, PPS (6 mg/mL), or liposomes (2 mg/mL) for 2 h. The variables measured included the intercontraction interval (ICI), pressure threshold (PT) and baseline pressure (BP). RESULTS: Sequential infusion of protamine sulphate/KCl induced hyperactive bladder with no significant difference in ICI, PT or BP among groups before initiating treatment. ICI was significantly increased after infusion of PPS (58.1% increase) and liposomes (156.8% increase) but there was no increase with DMSO. PT was not significantly affected by liposome infusion but slightly increased with PPS (12.4% increase). There was a large and significant increase in PT and BP with DMSO (116.5% increase) and BP largely remained unchanged after instillation with liposomes or PPS. CONCLUSIONS: Intravesical liposomes and PPS have a beneficial effect in a bladder hyperactivity rat model, while acute instillation of DMSO does not. Intravesical liposomes were effective in doubling the ICI compared with PPS, and might be a new treatment option for bladder hyperactivity.

Early capsaicin intervention for neurogenic bladder in a rat model of spinal cord injury.

We explored capsaicin pretreatment, prior to spinal trauma, as a method to prevent the development of neurogenic detrusor overactivity (NDO) and urethral-bladder dyssynergia reflex after spinal cord injury (SCI). In addition, the duration of effect of capsaicin therapy on NDO in a rat model of SCI was investigated. Two sets of experiments were performed on female Sprague Dawley rats transected at the T9-T10 spinal level. First, SCI rats received capsaicin (125 mg/kg s.q.) 3-4 days before and 4-5 days after SCI. Cystometrograms (CMG) was performed 4 weeks after injury. In the second set of experiments, serial CMG in the same SCI animal was performed after one time injection of capsaicin (125 mg/kg s.q.) 4 weeks after spinalization. There were no differences in intercontraction intervals, voiding efficiency, or voiding pressure between the capsaicin pretreated and control SCI rats. However, the number of uninhibited detrusor contractions decreased 4 weeks after injury. We found that a single dose of capsaicin suppressed uninhibited detrusor contractions for 34 days in the chronic SCI animals. Early therapy with capsaicin was able to prevent/reduce detrusor hyperreflexia in spinal cord injured animals 4 weeks after injury. Early vanilloid therapy may prevent development of urologic sequelae after SCI.

Effect of hyperforin-enriched extract on pro-ejaculatory effect of 8-hydroxy-2-(di-N-propylamino)tetralin in anesthetized rats.

OBJECTIVES: Premature ejaculation is the most common male sexual dysfunction and, yet, no approved effective therapies are currently available. We studied the in vivo effectiveness of hyperforin (HF), a concentrated extract of Hypericum perforatum in an experimental model for the expulsion phase of ejaculation in anesthetized rats. METHODS: The ejaculation model involved inducing rhythmic bulbospongiosus (BS) muscle contractions in male rats under urethane anesthesia (1.2 g/kg subcutaneously) by transiently raising the internal urethral pressure with saline infusion for 2 seconds at a rate of 116 microL/s. Electrodes in the BS muscles recorded the electrical activity during the contractions as a cluster of bursts on the electromyogram. Injection of the 5-hydroxytryptamine type 1A agonist 8-hydroxy-2-(di-N-propylamino)tetralin (8-OH-DPAT) (0.4 mg/kg subcutaneously) intensified the BS muscle contractions induced by increases in urethral pressure. RESULTS: Administration of 8-OH-DPAT strongly accelerated the ejaculation in the vehicle-treated rats and the amplitude of electrical discharges and the duration of electrical bursts accompanying the increases in urethral pressure were increased from baseline by 203.2% +/- 32.9% and 178.1% +/- 22.9%, respectively. The HF extract reduced the effects of 8-OH-DPAT on ejaculation at lower doses when tested in the dose range of 5 to 80 mg/kg. The reduction in the amplitude of bursts with HF extract remained unchanged after a midthoracic spinal transection, suggesting that the action of HF is either at the spinal ejaculation generator or directly on the neurons innervating the BS muscles. CONCLUSIONS: This is the first report of the effect of HF in a rat model of ejaculation. HF can be considered a novel new treatment of premature ejaculation.

Intraprostatic capsaicin injection as a novel model for nonbacterial prostatitis and effects of botulinum toxin A.

OBJECTIVES: An animal model for nonbacterial prostatitis in rats was developed with the use of intraprostatic injection of capsaicin, an agent thought to excite C-afferent fibers and cause neurogenic inflammation. The analgesic and anti-inflammatory properties of botulinum toxin type A (BoNT-A) was tested in this model. METHODS: Adult male Spraque-Dawley rats were injected with varying doses of capsaicin into the prostate. The nociceptive effects of capsaicin were evaluated for 30min by using a behavior approach; then the prostate was removed for histology and cyclooxygenase (COX) 2 protein concentration measurement. Evans blue (50mg/kg) was also injected intravenously to assess for plasma protein extravasation. A second set of animals were injected with up to 20U of BoNT-A into the prostates 1 wk prior to intraprostatic injection of 1000micromol/l capsaicin. RESULTS: Capsaicin dose dependently induced modifications in pain behavior: closing of the eyes, hypolocomotion, and inflammatory changes: increase of inflammatory cell accumulation, COX2 expression, and plasma extravasation at the acute stage, but completely recovered at 1 wk. BoNT-A pretreatment dose dependently reversed pain behavior and inflammation. BoNT-A 20U significantly decreased inflammatory cell accumulation, COX2 expression, and Evans blue extraction (82.1%, 83.0%, and 50.4%, respectively), and reduced pain behavior (66.7% for eye score and 46.5% for locomotion score). CONCLUSIONS: Intraprostatic capsaicin injection induced neurogenic prostatitis and prostatic pain, and may be a useful research model. BoNT-A produced anti-inflammatory and analgesic effects, and support clinical evaluation in prostatitis.