The spontaneously hypertensive rat: insight into the pathogenesis of irritative symptoms in benign prostatic hyperplasia and young anxious males

Hypertension facilitates age-related diseases. ~ Is hypertension associated with a wide variety of diseases?~

Hypertension, a disease whose prevalence increases with age, induces pathological conditions of ischemic vascular disorders such as cerebral infarction and myocardial infarction due to accelerated arteriosclerosis and circulatory insufficiency of small arteries and sometimes causes hemorrhagic conditions such as cerebral hemorrhage and ruptured aortic aneurysm. On the other hand, as it is said that aging starts with the blood vessels, impaired blood flow associated with vascular aging is the basis for the development of many pathological conditions, and ischemic changes in target organs associated with vascular disorders result in tissue dysfunction and degeneration, inducing organ hypofunction and dysfunction. Therefore, we hypothesized that hypertension is associated with all age-related vascular diseases, and attempted to review the relationship between hypertension and diseases for which a relationship has not been previously well reported. Following our review, we hope that a collaborative effort to unravel age-related diseases from the perspective of hypertension will be undertaken together with experts in various specialties regarding the relationship of hypertension to all pathological conditions.

Insights into the associative role of hypertension and angiotensin II receptor in lower urinary tract dysfunction

In men, the lower urinary tract comprises the urinary bladder, urethra, and prostate, and its primary functions include urine storage and voiding. Hypertension is a condition that causes multi-organ damage and an age-dependent condition. Hypertension and the renin-angiotensin system activation are associated with the development of lower urinary tract dysfunction. Hypertensive animal models show bladder dysfunction, urethral dysfunction, and prostatic hyperplasia. In the renin-angiotensin system, angiotensin II and the angiotensin II type 1 receptor, which are expressed in the lower urinary tract, have been implicated in the pathogenesis of lower urinary tract dysfunction. Moreover, among the several antihypertensives, renin-angiotensin system inhibitors have proven effective in human and animal models of lower urinary tract dysfunction. This review aimed to elucidate the hitherto known mechanisms underlying the development of lower urinary tract dysfunction in relation to hypertension and the angiotensin II/angiotensin II type 1 receptor axis and the effect of renin-angiotensin system inhibitors on lower urinary tract dysfunction. Possible mechanisms through which hypertension or activation of Ang II/AT1 receptor axis causes LUTD such as bladder dysfunction, urethral dysfunction, and prostatic hyperplasia. LUT: lower urinary tract, LUTD: lower urinary tract dysfunction, AT1: angiotensin II type 1, ACE: angiotensin-converting enzyme.

Association of diabetes, hypertension, and their combination with basal symptoms and treatment responses in overactive bladder patients

Introduction: Pelvic hypoperfusion caused by atherosclerosis has been proposed as a cause of lower urinary tract dysfunction including overactive bladder syndrome (OAB). Limited data indicate that OAB patients with concomitant diabetes or hypertension, known risk factors of atherosclerosis, may exhibit greater baseline OAB symptoms and slightly smaller therapeutic responses to treatment, but the impact of a combined presence of diabetes and hypertension has not been reported. Therefore, we have explored whether the combined presence of both comorbidities is associated with greater baseline OAB symptoms than that of either comorbidity alone. Secondary questions were exploration of the impact of either comorbidity on baseline symptoms, and of the impact of either comorbidity alone and their combination on therapeutic responses.

Methods: Data from two non-interventional studies applying treatment with propiverine ER 30 or 45 mg/d for 12 weeks were analyzed.

Results: Number of urgency episodes in the combination group was greater than with each comorbidity alone. The impact of comorbidities on baseline intensity of incontinence, frequency or nocturia or Patient Perception of Bladder Condition was less consistent or absent. Either comorbidity alone was associated with a smaller % improvement of symptoms, and their combination had a greater effect than either alone. However, all attenuations associated with comorbidity were small relative to the overall improvement.

Conclusions: We conclude that comorbidities of diabetes and hypertension have detectable effects on OAB symptoms and treatment responses, but the small magnitude of these alterations does not justify changing existing paradigms for the clinical management of OAB.

Skin sympathetic nerve activity as a potential biomarker for overactive bladder

PURPOSE

Abnormalities in autonomic function are associated with an overactive bladder (OAB). Heart rate variability is generally used as the sole assessment of autonomic activity; however, we utilized neuECG, a novel method of recording skin electrical signals, to assess autonomic nervous function in healthy controls and patients with OAB before and after treatment.

METHODS

The prospective sample included 52 participants: 23 patients newly diagnosed with OAB and 29 controls. Autonomic function was assessed in all participants in the morning using neuECG, which analyzed the average skin sympathetic nerve activity (aSKNA) and electrocardiogram simultaneously. All patients with OAB were administered antimuscarinics; urodynamic parameters were assessed before treatments; autonomic and bladder functions using validated questionnaires for OAB symptoms were evaluated before and after OAB treatment.

RESULTS

Patients with OAB had significantly higher baseline aSKNA (p = 0.003), lower standard deviation of the normal-to-normal beat intervals, lower root mean square of the successive differences, lower high-frequency, and higher low-frequency than did controls. Baseline aSKNA had the highest value in predicting OAB (AUROC = 0.783, p < 0.001). The aSKNA was negatively correlated with first desire and normal desire in urodynamic studies (both p = 0.025) and was significantly decreased after treatment at rest, stress, and recovery phases, as compared to those before treatment (p = 0.046, 0.017, and 0.017, respectively).

CONCLUSION

Sympathetic activity increased significantly in patients with OAB compared to that in healthy controls, and decreased significantly post-treatment. Higher aSKNA is associated with decreased bladder volume at which voiding is desired. SKNA may be a potential biomarker for diagnosing OAB.

Lycopene ameliorates locomotor activity and urinary frequency induced by pelvic venous congestion in rats

Decreased locomotor activity and altered urinary frequency are induced by bilateral common iliac vein ligation in rats. As a carotenoid, lycopene has a strong anti-oxidative function. This research investigated the function of lycopene in the pelvic venous congestion (PC) rat model and the underlying molecular mechanism. Lycopene and olive oil were administered intragastrically on a daily basis for 4 weeks after successful modeling. Locomotor activity, voiding behavior, and continuous cystometry were analyzed. The levels of 8-hydroxy-2'-deoxyguanosine (8-OHdG), nitrate and nitrite (NO _x ), and creatinine in the urine were measured. Gene expression in the bladder wall was analyzed by quantitative reverse transcription polymerase chain reaction, enzyme-linked immunosorbent assay, and Western blot. Locomotor activity, single voided volume, the interval between the bladder contractions, and urinary NO _x /cre ratio were all decreased in rats with PC, while the frequency of urination, urinary 8-OHdG/cre ratio, inflammatory responses, and nuclear factor-κB (NF-κB) signal activity were all increased. Lycopene treatment increased locomotor activity, decreased frequency of urination, elevated urinary NO _x level, and decreased urinary 8-OHdG level in the PC rat model. Lycopene also inhibited PC-enhanced pro-inflammatory mediator expression and NF-κB signaling pathway activity. In conclusion, lycopene treatment ameliorates PC-induced phenotypes and shows an anti-inflammatory effect in the PC rat model.

Weak association between arterial hypertension and overactive bladder baseline symptoms and treatment responses

While animal studies have suggested an association between the presence of hypertension and the presence and/or severity of overactive bladder syndrome (OAB) symptoms, little clinical data is available. We have conducted a pre-specified secondary analysis of a non-interventional study involving 4450 OAB patients being treated with solifenacin to explore the existence of an association between OAB and hypertension using three parallel and overlapping definitions of hypertension to enhance robustness of analysis. Regardless of definition, patients with hypertension were older and had greater OAB symptom severity in univariate analyses. In multiple regression models including age as explanatory covariate, most relationships held up but effect sizes of concomitant hypertension on OAB severity were small (odds ratios <1.35 in all cases) and were deemed to be unlikely of clinical relevance. % Changes in symptom severity were somewhat smaller in univariate analysis, but effect sizes were small. We conclude that OAB and arterial hypertension are associated but effect sizes are too small to justify adaptation of clinical practice for OAB patients with concomitant hypertension.

The surgical effect on overactive bladder symptoms in women with pelvic organ prolapse

This study aimed to explore the effect of pelvic reconstruction surgery on the relation of pelvic organ prolapse (POP) and overactive bladder (OAB) and the impact of preoperative vaginal oestrogen supplement on vaginal tissue. A total of 100 postmenopausal women with symptomatic POP who underwent pelvic reconstruction surgery (laparoscopic sacrocolpopexy or transvaginal mesh) were enrolled in this study. Preoperative vaginal oestrogen was prescribed in 28 cases. The evaluation tools consisted of POP-Q, urodynamic study, Overactive Bladder Symptom Score (OABSS), and urinary NGF. Vaginal maturation index and vaginal specimens for hormone receptors study were investigated during operation to evaluate the effect of topical oestrogen. Follow-up assessments were performed at 1, 3, and 6 months after surgery. Preoperatively, 58 (58%) were POP with OAB. After reconstruction surgery, the OABSS decreased significantly (6.87 ± 0.85 vs 3.77 ± 0.61, p < 0.001) at postoperative 6 months in the group. Remarkable increasing trends of urinary NGF levels are noted till 3 months postoperatively, then decreasing to the baseline level at 6 months postoperative follow-up. Remarkable decrease of mRNA of the androgen receptor and significant higher expression of progesterone receptor (PR) were noted after use of the vaginal oestrogen cream. The severity of OAB in the POP women shows moderate degree according to OABSS. Pelvic reconstruction surgery can significantly improve the OAB symptoms. The surgery induced inflammation effect lasts for about 6 months. Short-term preoperative supplement of topical oestrogen brings alterations of the vaginal epithelium.

Voiding behavior in awake unrestrained untethered spontaneously hypertensive and Wistar control rats

The spontaneously hypertensive rat (SHR), a genetic model of high blood pressure, has also been studied as a potential model of overactive bladder. In vivo studies have confirmed the presence of surrogate markers of overactive bladder, including detrusor overactivity, increased urinary frequency, decreased bladder capacity and voided volume (VV), and afferent hypersensitivity to bladder irritation. However, these observations were during awake cystometry using implanted bladder catheters tethered to an infusion pump and artificially filled. We conducted experiments in awake unrestrained untethered age-matched female SHRs and Wistar rats to quantify naïve consumption and voiding behavior and the effect of capsaicin desensitization on consumption and voiding behavior. Food and water consumption, body weight, voiding frequency, and VV were recorded. Rats were placed in metabolism cages for 24 h, up to twice a week, from 17 to 37 wk of age. Compared with Wistar rats, SHRs exhibited decrease in VV and did not exhibit diurnal variation in VV between light and dark periods, suggesting that SHRs may have bladder hypersensitivity. Furthermore, SHRs may also have smaller bladder capacities, as they consumed less water, voided less volume (regardless of light cycle), and had equal urinary frequencies compared with age-matched Wistar rats. We detected no change in SHR voiding behavior following capsaicin desensitization, which was in contrast to a prior awake in vivo cystometry study describing increased VV and micturition interval in SHRs and suggests that C-fiber activity may not contribute to bladder hypersensitivity in SHRs.NEW & NOTEWORTHY We characterized the long-term (20 wk) voiding, defecation, and consumption behavior of age-matched spontaneously hypertensive and Wistar rats without the influence of anesthesia or catheters. Spontaneously hypertensive rats exhibited bladder hypersensitiviy that persisted for the 20-wk duration and was unaffected by capsacin desensitization.

Effects of silodosin and tadalafil on bladder dysfunction in spontaneously hypertensive rats: Possible role of bladder blood flow

OBJECTIVES

To investigate the effects of an alpha1-adrenoceptor antagonist, silodosin, or a phosphodiesterase type 5 inhibitor, tadalafil, on bladder overactivity in spontaneously hypertensive rats.

METHODS

Twelve-week-old male spontaneously hypertensive rats were perorally administered silodosin (100 µg/kg), tadalafil (2 or 10 mg/kg) or vehicle once daily for 6 weeks. Wistar rats were used as normotensive controls and were treated with the vehicle. At 18-weeks-old, the effects of silodosin or tadalafil on blood pressure, bladder blood flow, urodynamic parameters (i.e. micturition frequency, urine output, inter-contraction interval, maximum voiding pressure, single voided volume and post-voiding residual urine volume), and bladder tissue levels of malondialdehyde, interleukin-6 and tumor necrosis factor-alpha were measured.

RESULTS

A significant increase in blood pressure, micturition frequency and bladder tissue levels of malondialdehyde, interleukin-6 and tumor necrosis factor-alpha was noted in spontaneously hypertensive rats. The single voided volume, bladder capacity and bladder blood flow were significantly lower in the spontaneously hypertensive rats than in the Wistar rats. Treatment with silodosin and the higher dose of tadalafil improved the urodynamic parameters, bladder blood flow and bladder tissue levels of malondialdehyde in the spontaneously hypertensive rats without affecting the blood pressure and bladder tissue levels of interleukin-6 and tumor necrosis factor-alpha.

CONCLUSIONS

Treatment with silodosin or tadalafil might improve hypertension-related bladder overactivity, as shown in spontaneously hypertensive rats through an improvement in the bladder blood flow and bladder tissue levels of oxidative stress.

Can we predict the success of prostatic surgery for male lower urinary tract symptoms: ICI-RS 2018?

AIMS

Male lower urinary tract symptoms (LUTS) are common and bothersome symptoms in the aging population, of which the etiology is multifactorial. Prostatic surgery may be considered to alleviate some of these LUTS, especially in patients in which benign prostatic obstruction is believed to be the underlying cause. The aim of this paper is to discuss underlying pathophysiology, signs, and conditions that may lead to success or failure after prostatic surgery in male patients with LUTS.

METHODS

The paper is a report of presentations and subsequent discussions at the annual International Consultation on Incontinence Research Society, in June 2018 in Bristol.

RESULTS AND CONCLUSIONS

Unfavorable outcomes after prostatic surgery are reported in 25% to 30% of the patients. This may be due to persistent or de novo symptoms, related to the multifactorial origin of symptoms. Specific underlying conditions such as with detrusor overactivity, detrusor underactivity, and nocturnal polyuria are discussed in their relationship with prostatic surgery. Knowledge gaps are addressed and specific research questions proposed.

Hydrogen sulfide-induced relaxation of the bladder is attenuated in spontaneously hypertensive rats

PURPOSE

To compare hydrogen sulfide (H₂S)-induced relaxation on the bladder between normotensive and spontaneously hypertensive rat (SHR), we evaluated the effects of H₂S donors (GYY4137 and NaHS) on the micturition reflex and on the contractility of bladder tissues. We also investigated the content of H₂S and the expression levels of enzymes related to H₂S biosynthesis [cystathionine β-synthase (CBS), 3-mercaptopyruvate sulfurtransferase (MPST), and cysteine aminotransferase (CAT)] in the bladder.

METHODS

Eighteen-week-old male normotensive Wistar rats and SHRs were used. Under urethane anesthesia, the effects of intravesically instilled GYY4137 (10^-8, 10^-7 and 10^-6 M) on the micturition reflex were evaluated by cystometry. The effects of NaHS (1 × 10^-8-3 × 10^-4 M) were evaluated on carbachol (10^-5 M)-induced pre-contracted bladder strips. Tissue H₂S content was measured by the methylene blue method. The expression levels of these enzymes were investigated by Western blot.

RESULTS

GYY4137 significantly prolonged intercontraction intervals in Wistar rats, but not in SHRs. NaHS-induced relaxation on pre-contracted bladder strips was significantly attenuated in SHRs compared with Wistar rats. The H₂S content in the bladder of SHRs was significantly higher than that of Wistar rats. CBS, MPST and CAT were detected in the bladder of Wistar rats and SHRs. The expression levels of MPST in the SHR bladder were significantly higher than those in the Wistar rat bladder.

CONCLUSION

H₂S-induced bladder relaxation in SHRs is impaired, thereby resulting in a compensatory increase of the H₂S content in the SHR bladder.

Tadalafil improves bladder dysfunction and object recognition in rats with pelvic venous congestion

OBJECTIVES

To examine the effects of tadalafil on bladder function and object recognition ability in rats with alterations in urinary frequency and locomotor activity as a result of pelvic venous congestion.

METHODS

A total of 48 female rats were divided into three groups (sham, pelvic venous congestion and pelvic venous congestion/tadalafil groups). In the pelvic venous congestion and pelvic venous congestion/tadalafil groups, the bilateral common iliac veins and uterine veins were ligated under anesthesia. Rats in the pelvic venous congestion/tadalafil group received a diet containing tadalafil, and the other rats were fed a normal diet. After 4 weeks, rats underwent analysis of voiding behavior, locomotor activity, a novel object recognition test, continuous cystometry, measurement of plasma monoamines, and measurement of plasma and urinary nitric oxide metabolites. Expression of nitric oxide synthase messenger ribonucleic acid in the bladder wall was also assessed, along with histological examination of the bladder.

RESULTS

Rats with pelvic venous congestion showed a higher urinary frequency, lower locomotor activity, and lower plasma and urinary nitric oxide levels than sham rats. The bladder wall endothelial nitric oxide synthase messenger ribonucleic acid level was low and object recognition was impaired. Pelvic venous congestion/tadalafil rats showed improvement in locomotor activity, bladder function and object recognition compared with pelvic venous congestion rats, as well as elevation of plasma and urinary nitric oxide, plasma monoamines, and bladder neuronal nitric oxide synthase messenger ribonucleic acid expression. Bladder wall vascularity was greater in pelvic venous congestion/tadalafil rats compared with sham rats.

CONCLUSIONS

In rats with pelvic venous congestion, tadalafil might improve bladder function and the general condition by increasing blood flow to the bladder and brain, and by increasing dopamine levels.

Relationship of blood flow in the common iliac vein to lower urinary tract disease

PURPOSE

The relationship between blood flow and lower urinary tract disease was explored by measuring blood flow in the common iliac vein to examine the influence of pelvic congestion on lower urinary tract symptoms.

METHODS

Color Doppler ultrasonography of the right common iliac vein was performed in 113 men and 60 women, who were outpatients of two Japanese hospitals. Average blood flow velocity and cross-sectional area of the vein were measured, and blood flow volume was calculated. The relationship between these parameters and age or urological diseases was then examined.

RESULTS

There was no relation between age and average blood flow velocity or blood flow volume of the common iliac vein in either men or women. However, average common iliac vein blood flow velocity was significantly lower in men with chronic prostatitis and in women with overactive bladder than in other male and female patients, respectively. Common iliac vein blood flow volume was also significantly lower in men with chronic prostatitis than in other male patients.

CONCLUSIONS

Men with chronic prostatitis and women with overactive bladder have low blood flow in the common iliac vein, suggesting that pelvic congestion may be related to these two conditions.

Pelvic venous congestion induces lower urinary tract dysfunction in rats

Pelvic venous congestion (PC) is thought to be related to several diseases of the lower urinary tract (LUT). We examined the characteristics of the LUT in rats with PC. To create PC, female rats were anesthetized with isoflurane, and the bilateral common iliac veins and bilateral uterine veins were ligated. At 1-8 weeks after either ligation or sham surgery, we performed cystometry with or without administration of carbazochrome sodium sulfonate hydrate or propiverine hydrochloride, histologic examination of the bladder, blood flow imaging, assessment of locomotor activity, measurement of urinary 8-hydroxydeoxyguanosine (8-OHdG) and nitric oxide metabolites (NOx), and the Evans blue dye extravasation test. PC elevated frequency of urination after 2-6 weeks, and caused a decrease of spontaneous locomotor activity. In addition, there was a decrease of bladder blood flow, an increase of bladder vascular permeability, an increase of urinary 8-OHdG, a decrease of urinary NOx, and mild inflammatory changes of the bladder. In rats with PC, frequency of urination was normalized by administration of propiverine or carbazochrome. Rats with PC may be used as a model of PC associated with high frequency of urination, and this model may be useful when developing treatment for LUT symptoms associated with PC.

Relationship Between Central Obesity, General Obesity, Overactive Bladder Syndrome and Urinary Incontinence Among Male and Female Patients Seeking Care for Their Lower Urinary Tract Symptoms

OBJECTIVES

To describe the relationship between metabolic factors and lower urinary tract symptoms, overactive bladder syndrome (OAB) and urinary incontinence (UI).

METHODS

Adult male and female patients who presented to a clinician from the symptoms of lower urinary tract dysfunction research network were recruited. Urinary symptoms (presence of OAB, any UI, stress UI (SUI), urgency UI (UUI), urgency, frequency, and nocturia) were assessed with the lower urinary tract symptoms tool. Metabolic factors assessed included central obesity (waist circumference, using the Adult Treatment Panel III, the International Diabetes Federation thresholds, and waist circumference as a continuous variable), general obesity (body mass index as dichotomous or continuous variables), diabetes mellitus, hypertension, and dyslipidemia. Multivariable logistic regression was used to test for associations.

RESULTS

920 participants were studied. In multivariable analyses, central obesity (per 10 cm larger waist) was associated with higher odds of UI in both sexes (odds ratio [OR] = 1.16, P = .008), SUI in females (OR = 1.27, P = .008), UUI in both sexes (OR = 1.24, P = .001), OAB in females (OR = 1.248, P = .003), as well as frequency and nocturia. General obesity (5-unit increase in body mass index) was associated with UI, UUI, urgency and frequency in both sexes, and with SUI and OAB in females. We did not find associations between central or general obesity and OAB in males. Dyslipidemia was associated with nocturia ≥2.

CONCLUSION

In patients, central and general obesity were key metabolic factors associated with UI in both males and females, and with OAB in females but not in males. The association between dyslipidemia and nocturia ≥2 needs further research.

Naftopidil improves locomotor activity and urinary frequency in rats with pelvic venous congestion

The α1D/A receptor antagonist, naftopidil, inhibits micturition reflex by acting on various different sites. We examined the effects of naftopidil on bladder activity and changes in the induced urinary frequency using female rats with pelvic venous congestion (PC). Twenty-four female rats were divided into sham, PC, and PC/naftopidil groups. After anesthetizing rats in the PC and PC/naftopidil groups, the bilateral common iliac veins and uterine veins were ligated. Rats in the sham and PC groups were fed a standard diet, while rats in the PC/naftopidil group were fed diets containing 0.04% naftopidil. After 4 weeks of treatment, locomotor activity, urinary nitric oxide metabolites (NOx), continuous cystometry, and plasma monoamine measurements were performed. PC rats exhibited a decrease of locomotor activity, a shorter interval between bladder contractions on continuous cystometry, and decreased urinary NOx and plasma serotonin levels than the sham rats. The PC/naftopidil rats exhibited an increase of locomotor activity, a longer interval between bladder contractions, and increased urinary NOx and plasma serotonin levels. Therefore, naftopidil might improve bladder dysfunction induced by pelvic venous congestion due to several actions in the central nervous system and bladder tissue, as well as acting as an α1 blocker to cause pelvic venous dilation.

Effects of Gegen (Puerariae lobatae Radix) water extract on improving detrusor overactivity in spontaneously hypertensive rats

AIM

Ex vivo experiments showed that the water extract of Puerariae lobatae Radix (named Gegen in Chinese) induced detrusor relaxation. The aim of this study was to prove the in vivo efficacy of Gegen on improving detrusor overactivity and its possible synergism with darifenacin (a first-line muscarinic receptor-3 inhibitor) in spontaneously hypertensive rats (SHR), a rat model exhibiting symptoms of detrusor overactivity.

METHOD

After daily oral administration of Gegen 30 (Gegen, 30mg/kg); Gegen 300 (Gegen, 300mg/kg); Low_Dar (darifenacin, 3mg/kg); High_Dar (darifenacin, 30mg/kg) Low_Dar+Gegen 30 or High_Dar+Gegen 30 for 3 weeks, bladder detrusor strips of the rats were isolated and assessed with different stimulators for the measurement of tonic and phasic contractile activities (including phasic amplitude and frequency). Modes of stimulation included the use of carbachol, isoprenaline and electrical field stimulation (EFS).

RESULTS

All drug treatments significantly reduced carbachol-stimulated tonic contractile activities, but did not change the phasic amplitude. Meanwhile, the treatments with Gegen 300; Low_Dar; Low_Dar+Gegen 30; and High_Dar+Gegen 30 decreased carbachol-stimulated phasic frequency. Gegen 300 and Low_Dar+Gegen 30 showed stronger potency on lowering EFS-induced responses. Under isoprenaline-induced relaxation, only Gegen 300 significantly enhanced this relaxation by decreasing tonic contraction; Gegen 300; Low_Dar; Low_Dar+Gegen 30; and High_Dar+Gegen 30 increased the reduction of phasic frequency, but all treatment did not alter their phasic amplitude. Combination Index (CI) showed that the combination with Low_Dar and Gegen 30 had very strong synergism (CI <0.1) on inhibiting EFS-induced contractile response.

CONCLUSION

Gegen improved detrusor overactivity through neurogenic and anti-muscarinic mechanisms. Gegen and darifenacin together attained synergism for detrusor overactivity treatment via the neurogenic pathway.

Solifenacin and Tamsulosin Combination Therapy Decreases Urine Nerve Growth Factor/Creatinine Levels in Men

OBJECTIVE

To evaluate urinary nerve growth factor (NGF)/creatinine (Cr) levels from men with symptomatic lower urinary tract symptoms (LUTS) and measure the effect of combination therapy with solifenacin and tamsulosin.

MATERIALS AND METHODS

From January 2012 to February 2014, all male patients referred for evaluation and management of LUTS were screened for enrollment. In all subjects, urinary NGF and Cr levels were measured and normalized to the urinary Cr concentrations (NGF/Cr). Uroflow, postvoid residual, and symptom questionnaires were measured at baseline, 4 weeks, 8 weeks, and 12 weeks after starting combination therapy with solifenacin 5 mg and tamsulosin 0.4 mg. The primary endpoint was urinary NGF and NGF/Cr change from baseline compared with week 12.

RESULTS

Ten patients were recruited into the study. Peak urine flow at baseline 20.3 ± 2.5 ml/s and postvoid residual 45.3 ± 13.6 ml did not significantly change with 3 months of combination treatment 14.9 ± 1.8 ml/s and 58.5 ± 23.9 ml. However, urine NGF/Cr (pg/mg) levels were significantly reduced following treatment with levels of 39.7 ± 6.6 at baseline to 17.9 ± 5.1 at 3 months (P value <.05). The decrease in urine NGF/Cr levels correlated with significant decreases in patient reported outcomes.

CONCLUSION

Male patients with LUTS had decreased urinary NGF/Cr levels after treatment with combination solifenacin and tamsulosin in this novel pilot study. This corresponded with improvement in patient reported outcomes.

The association of urinary nerve growth factor levels with bladder outlet obstruction in women

OBJECTIVES

Nerve growth factor (NGF) has been proposed as a urinary biomarker and previously shown to be elevated in male patients with bladder outlet obstruction (BOO) and other lower urinary tract symptoms. No published studies have examined NGF as a potential urinary biomarker in women with BOO. The aims of this prospective study were to evaluate NGF levels in urine from women with anatomic BOO resulting from pelvic organ prolapse (POP) and/or previous incontinence surgery and to measure the effect associated with surgical or conservative management.

METHODS

From January to September 2012, all female patients referred for evaluation and management of BOO from POP or previous incontinence surgery were screened for enrollment. Inclusion criteria included elevated postvoid residual, valsalva voiding on urodynamics, or urinary peak flow (Qmax) of 12 mL/s or less. A control group of 10 asymptomatic age-matched female volunteers was also recruited. In all subjects, urinary NGF and creatinine (Cr) levels were measured and normalized to the urinary Cr concentrations (NGF/Cr). Urinary NGF levels were measured at 1 month and 3 months after either surgical correction or initiation of clean intermittent catheterization.

RESULTS

A total of 10 female patients with anatomic BOO (mean [SD] age of 66.2 [3.88] years) and 10 female control subjects (mean [SD] age of 62 [7] years) were recruited. Nine patients had POP. Six patients had undergone a previous anti-incontinence procedure. Five patients had both POP and undergone a previous anti-incontinence procedure. The urinary NGF/Cr levels in the study patients with BOO (mean [SE] 20.8 [4.31] pg/mg) were significantly higher (P = 0.0001) than the levels in the age-matched control group (5.6 [0.65] pg/mg). After treatment, the urinary NGF/Cr level significantly decreased to 6.50 (0.57) pg/mg (P = 0.01) CONCLUSIONS: In this study, female patients with anatomic BOO resulting from POP and/or previous incontinence surgery had significantly higher urinary NGF/Cr levels when compared with age-matched controls. After treatment, the urinary NGF/Cr levels significantly decreased.

Underlying mechanisms of urine storage dysfunction in rats with salt-loading hypertension

AIMS

Spontaneous hypertensive rats provide a genetic model for exploring the pathogenesis of urine storage dysfunction related to hypertension (HT). In humans, however, HT develops by both genetic and environmental factors including lifestyle factors such as a high-calorie diet, excessive salt intake and stress. We investigated the influence of salt-loading on bladder function and the underlying mechanisms of storage dysfunction related to HT.

MAIN METHODS

Six-week-old male Dahl salt-sensitive (DS) and Dahl salt-resistant (DR) rats were fed with a normal or high-salt diet for 12weeks. Micturition parameters were obtained from a metabolic cage. Whole bladders were excised from 18-week-old rats and distended in an organ bath. The releases of adenosine triphosphoric acid (ATP) and prostaglandin E2 (PGE2) from the distended bladder epithelia were measured. Changes in bladder blood flow (BBF) were determined with a laser-speckle-blood-flow imaging system.

KEY FINDINGS

An increase in mean blood pressure (BP) was noted only in DS rats after salt-loading. During the inactive (sleeping) period, voided volume per micturition gradually increased in DR rats fed a normal or high-salt diet and normal-diet DS rats, while it did not change in the DS rats fed a high-salt diet. Bladder distension significantly increased ATP and PGE2 release from the urothelium in DS rats fed a high-salt diet. BBF was significantly decreased in high-salt-diet DS rats.

SIGNIFICANCE

One mechanism behind the relationship between salt-sensitive HT and urine storage dysfunction may be an increase in ATP and PGE2 release from the urothelium via suppression of BBF.

Are polymorphisms of the β(3)-adrenoceptor gene associated with an altered bladder function?

AIMS

As the presence of a Trp64Arg polymorphism of the gene encoding the β(3)-adrenoceptor (B3AR) has been linked to the presence of overactive bladder, we investigated whether additional polymorphisms are detectable in this gene and explore their relationships parameters related to lower urinary tract function.

METHODS

The coding region and adjacent stretches of the B3AR gene was sequenced in 91 patients. In total, 1015 patients from a single academic hospital were genotyped for the presence of two single nucleotide polymorphisms. Symptom scores and parameters from pressure-flow studies were analyzed relative to genotype in the B3AR gene.

RESULTS

No frequent novel polymorphisms were detected in the coding region. Five polymorphisms were found in the non-coding region of the gene but were in complete linkage with the 64Arg allele. Out of 32 parameters including bladder compliance, only prostate size was weakly (44 vs. 39 mL) but significantly associated with the 64Arg allele, but was not mirrored by an association with prostate-specific antigen levels.

CONCLUSIONS

Our data do not support the hypothesis that polymorphisms in the B3AR gene are associated with alterations of bladder function.

Insight into new potential targets for the treatment of overactive bladder and detrusor overactivity

Although overactive bladder (OAB) and detrusor overactivity (DO) are not synonyms, they share therapeutic options and partially underlying physiopathological mechanisms. The aim of this overview is to give insight into new potential targets for the treatment of OAB and DO. A narrative review was done in order to reach this goal. Ageing, pelvic floor disorders, hypersensitivity disorders, morphologic bladder changes, neurological diseases, local inflammations, infections, tumors and bladder outlet obstruction may alter the normal voluntary control of micturition, leading to OAB and DO. The main aim of pharmacotherapy is to restore normal control of micturition, inhibiting the emerging pathological involuntary reflex mechanism. Therapeutic targets can be found at the levels of the urothelium, detrusor muscles, autonomic and afferent pathways, spinal cord and brain. Increased expression and/or sensitivity of urothelial-sensory molecules that lead to afferent sensitization have been documented as a possible pathogenesis of OAB. Targeting afferent pathways and/or bladder smooth muscles by modulating activity of ligand receptors and ion channels could be effective to suppress OAB.

Development and changes with age of detrusor overactivity in spontaneous hypertensive rats as observed by simultaneous registrations of intravesical and intraabdominal pressures

Purpose

Overactive bladder is especially common in the elderly, although it is not regarded as a normal part of aging. Thus, we investigated how aging alters the cystometric and detrusor overactivity (DO) parameters and the density of nerve growth factor (NGF) in awake spontaneous hypertensive rats (SHRs) of different ages.

Methods

Three age groups of 12- (n=5), 17- (n=6), and 21- (n=6) week-old SHRs (Oriental Bio Inc.) were used. A catheter was implanted into the bladder to record the intravesical pressure (IVP), and a balloon-fitted catheter was positioned in the abdominal cavity to record the intraabdominal pressure (IAP). Of the IVP elevations above 2 cm H₂O, DO was defined as a rise in IVP without a simultaneous change in IAP and was counted during the filling phase. We measured the expression of NGF in the bladders by enzyme-linked immunosorbent assay.

Results

Both the body and bladder weights significantly increased with age, but the normalized ratio between those was not changed. As for DO, none of the12-week-old rats showed DO, whereas the other groups did. DO increased significantly with age (P=0.0045 by Mantel-Haenszel trend test), although no significant differences were found in DO frequency or pressure between the 17- and 21-week-old age groups. NGF did not show any significant differences among the three groups.

Conclusions

Our results showed that SHRs begin to shows DO after a certain age, such as 12 weeks of age, and that the occurrence of DO has a close relationship with aging. However, NGF, which is known to be increased in the bladder wall of patients with overactive bladder, did not show any relationship with aging in this study.

Causative significance of bladder blood flow in lower urinary tract symptoms

The association between metabolic syndrome and lower urinary tract symptoms has been attracting enormous interest and attention. This enthusiasm is based on the presence of many common risk factors being involved in both metabolic syndrome and lower urinary tract symptoms, as shown by various epidemiological studies. Metabolic syndrome and lower urinary tract symptoms have many pathophysiological features in common, particularly overactive bladder. Herein, we analyze the pathophysiological relationship between metabolic syndrome and lower urinary tract symptoms with a special emphasis on bladder blood flow. We also propose a new treatment strategy for treating lower urinary tract symptoms from the viewpoint of bladder blood flow.

Effects of age and hypertension on α1-adrenoceptors in the major source arteries of the rat bladder and penis

α(1)-Adrenoceptors regulate blood pressure, regional vascular resistance and tissue blood flow. As aging and hypertension may impact pelvic arterial blood flow resulting in bladder and penile dysfunction, we investigated effects of age and hypertension on α(1)-adrenoceptors in the major source arteries of the rat bladder and penis. Using radioligand receptor binding, real-time reverse transcription-polymerase chain reaction (RT-PCR) and fluorescent microsphere infusion techniques, we compared 3 and 22-month-old male Fischer rats, and male normotensive Wistar-Kyoto (WKY) rats and spontaneously hypertensive rats (SHRs). Twenty-two-month-old rats and SHRs had significantly higher total α(1)-adrenoceptor density in the internal iliac artery and lower blood flow to the bladder and penis than 3-month-old and WKY rats, respectively. RT-PCR data showed an age and hypertension related increase in the expression of α(1B)-adrenoceptor mRNA in the internal iliac, vesical and internal pudendal arteries and a switch from α(1A) predominance in 3-month-old and WKY rats to α(1B)>α(1A) in 22-month-old rats and SHRs. Our data indicate the presence of age and hypertension related alterations in vascular α(1)-adrenoceptor subtype distribution and in blood flow to the rat bladder and penis. These findings suggest that pharmacological blockade of the vascular α(1B)-adrenoceptor, which could increase pelvic blood flow, may contribute to the improvement of bladder and penile dysfunctions in animal models for aging and hypertension.

Role of interleukins, IGF and stem cells in BPH

The condition known as benign prostatic hyperplasia may be defined as a benign enlargement of the prostate gland resulting from a proliferation of both benign epithelial and stromal elements. It might also be defined clinically as a constellation of lower urinary tract symptoms (LUTSs) in aging men. The purpose of this review is to consider the ways in which inflammatory cytokines belonging to the interleukin family, members of the IFG family, and stem cells may contribute to the development and progression of BPH-LUTS. This might occur in three mechanisms: One, interleukin signaling, IFG signaling and stem cells may contribute to reactivation of developmental growth mechanisms in the adult prostate leading to tissue growth. Two, given that epidemiologic studies indicate an increased incidence of BPH-LUTS in association with obesity and diabetes, IFG signaling may provide the mechanistic basis for the effect of diabetes and obesity on prostate growth. Three, expression of interleukins in association with inflammation in the prostate may induce sensitization of afferent fibers innervating the prostate and result in increased sensitivity to pain and noxious sensations in the prostate and bladder and heightened sensitivity to bladder filling.

Association between metabolic syndrome and pelvic floor dysfunction in middle-aged to older Korean women

OBJECTIVE

The purpose of this study was to evaluate the association of metabolic syndrome (MS) with female pelvic floor dysfunction in middle-aged to older Korean women.

STUDY DESIGN

A prospective cross-sectional study was performed that included a total of 984 Korean women (≥ 40 years old) who visited a comprehensive medical screening clinic. Pelvic floor dysfunction was assessed by the Pelvic Floor Distress Inventory-20 (PFDI-20); higher scores indicated a greater symptom burden.

RESULTS

The adjusted mean score on the PFDI-20, and especially the Urinary Distress Inventory-6 subscale, was significantly higher in subjects with MS than those without MS. Furthermore, the PFDI-20 and all 3 subscales were significantly increased in correlation with the number of MS components that were present (P < .05). In the multivariable analysis, MS was associated significantly with PFDI-20 (P = .002) and the 3 subscores (P < .05).

CONCLUSION

MS was significantly associated with the pelvic floor dysfunction among middle- to old-aged Korean women. Physicians should pay more attention to the pelvic floor symptoms for the patients with MS.

The association of adiposity and overactive bladder appears to differ by gender: results from the Boston Area Community Health survey

PURPOSE

We investigate the association of different measures of adiposity (waist circumference, hip circumference, waist-to-hip ratio and body mass index) with overactive bladder (urinary frequency and urgency), whether the association varies by gender or age and whether it persists when models are adjusted for other confounders.

MATERIALS AND METHODS

Data were from the Boston Area Community Health epidemiological survey, a random sample of 5,503 Boston, Massachusetts, residents 30 to 79 years old with equal representation from 3 racial/ethnic groups (black, Hispanic and white). Statistical analysis involved nonparametric loess models and multivariate logistic regression.

RESULTS

We noted distinct patterns by gender for the association of various adiposity measures with overactive bladder. Waist-to-hip ratio was not significantly associated with overactive bladder in either gender. In women the prevalence of overactive bladder increased as waist (OR adjusted for other confounders 1.10/10 cm increase) or hip circumference (OR 1.12/10 cm increase) or body mass index (OR 1.03/kg/m2 increase) increased. In men the prevalence of overactive bladder decreased as adiposity increased (OR 0.65/10 cm increase in waist circumference, OR 0.71/10 cm increase in hip circumference and OR 0.87/kg/m2 in body mass index) but only to a certain point (waist circumference 100 cm, hip circumference 115 cm and body mass index 27.5 kg/m2, respectively). At that point the prevalence of overactive bladder increased with increasing adiposity (OR 1.19/10 cm increase in waist circumference, OR 1.16/10 cm increase in hip circumference and OR 1.08/kg/m2 in body mass index).

CONCLUSIONS

The relationship between adiposity and overactive bladder varies by gender.

An open, non-comparative, multicentre study on the impact of alfuzosin on sexual function using the Male Sexual Health Questionnaire in patients with benign prostate hyperplasia

OBJECTIVES

To determine the effect of alfuzosin on sexual function by using the Male Sexual Health Questionnaire (MSHQ) in men with lower urinary tract symptoms (LUTS) suggestive of benign prostatic hyperplasia (BPH).

PATIENTS AND METHODS

In this multicentre, open-label and non-comparative study, a total of 135 sexually active patients with LUTS were enrolled in Korea to receive alfuzosin 10 mg once daily for 12 weeks. International Prostate Symptom Score (IPSS) and a 25-item MSHQ exploring erection ejaculation and satisfaction with sex life were evaluated at baseline after 4 and 12 weeks of treatment.

RESULTS

Of 135 patients (age 58.8 years, duration of LUTS 2.6 years, mean values), 110 (81.5%) completed the study. The ejaculatory domain of the MSHQ significantly improved at the end-point in the intent-to-treat population (score difference of 2.24, p < or = 0.0001, n = 120). The domains of erection and sexual satisfaction improved at the end-point, but the score differences were not statistically significant. After the 12 weeks treatment, the total IPSS score significantly decreased from 17.9 to 12.1 (p < 0.0001), bother score decreased from 3.8 to 2.85 (p < 0.0001) and peak flow rate increased from 11.0 to 14.3 ml/s (p < 0.0001). A significant relationship between ejaculatory domains of MSHQ and IPSS was found. Four patients (2.9%) discontinued the trial for adverse event.

CONCLUSIONS

Based on the analysis of MSHQ scores before and after alfuzosin treatment, improvement was significant on ejaculatory function, in addition to improvement on LUTS and quality of life. MSHQ is a useful tool to evaluate the male sexual dysfunction.

Etiology, epidemiology, and natural history of benign prostatic hyperplasia

Historically, benign prostatic hyperplasia (BPH) has been a major focus of urologic practice and surgery. But a simplistic causal relationship among prostatic enlargement, progressive obstruction, lower urinary tract symptoms, retention, and complications of retention has been challenged by recognition of the incomplete overlap of prostatic enlargement with symptoms and obstruction. The result has been a greater focus on symptoms than prostatic enlargement and a shift from surgery to medical treatment. Therefore, the question can be asked whether BPH per se, the glandular enlargement as it contributes to bladder dysfunction, or hyperplastic enlargement as a biomarker for generalized lower urinary tract dysfunction are concerns. This article addresses these issues.