Perilla extract improves frequent urination in spontaneously hypertensive rats with enhancement of the urothelial presence and anti‐inflammatory effects

Objective

To investigate the effects of perilla extract on urinary symptoms in spontaneously hypertensive rats as a model of spontaneous overactive bladder.

Methods

Spontaneously hypertensive rats were randomly divided into two groups and fed either a control diet or a perilla extract‐containing diet. Cystometry, gene expression and histological analyses were carried out to evaluate the effects of perilla extract after 2‐week feeding of either the control or the perilla extract diet. The expression of inflammation‐related genes in the human urothelial cell line HT‐1376 and the normal human bladder epithelial cell was measured after the treatment with perillaldehyde, the main component of perilla extract, or perillic acid, the final metabolite of perillaldehyde.

Results

A significant 27% increase in the micturition interval and decreased expression of nerve growth factor, tumor necrosis factor‐α, interleukin‐1β and transient receptor potential V1 were observed in the perilla group compared with the control group. The level of uroplakin 3A was 40% higher in the perilla group than in the control group. The urothelium in the control group was thin or defective, but it was almost completely intact in the perilla group. Perillaldehyde and perillic acid suppressed the induction of nerve growth factor and tumor necrosis factor‐α by interleukin‐1β in HT‐1376 and normal human bladder epithelial cells.

Conclusions

The present findings suggest that perilla extract improves frequent urination, and this improvement seems to be mediated, at least in part, by enhancement of the urothelial presence and by the anti‐inflammatory effects of perilla.     

Spontaneous activity of mouse detrusor smooth muscle and the effects of the urothelium

AIMS: To characterize the detrusor muscle of the mouse urinary bladder in order to understand more precisely spontaneous contractile behavior of this organ. This study examined the spontaneous electrical activity and Ca(2+) dynamics of the detrusor smooth muscle and investigated the role of the urothelium. MATERIALS AND METHODS: Detrusor smooth muscle strips were isolated from mouse bladders. The urothelium was either kept intact or removed. Changes in membrane potential were recorded using sharp electrode intracellular recording. To image Ca(2+) dynamics, tissue strips were exposed to 10 microM Oregon Green 488 BAPTA-1 AM for 70 min, and then image series were acquired with a laser-scanning confocal microscope. RESULTS: (1) Mouse detrusor smooth muscle cells (SMCs) generate nifedipine-sensitive spontaneous action potentials (sAPs) at a low frequency (1.3 +/- 0.9 min(-1), n = 11) in preparations with intact urothelium. This frequency increased when the urothelium was removed (7 +/- 8.3 min(-1), n = 17) (P < 0.05, Student's t test). (2) Frequent ATP-mediated spontaneous depolarizations were recorded in all cells. (3) The frequency of whole cell Ca(2+) flashes of detrusor smooth muscle cells was higher in preparations with the urothelium removed (median 1.2 min(-1), n = 7) than in urothelium denuded preparations (median 0.6 min(-1), n = 7) (P < 0.01, Mann-Whitney U-test). CONCLUSIONS: Spontaneous activity of the mouse detrusor smooth muscles was characterized enabling future comparative work on gene knock-out strains. Evidence suggesting release of an inhibitory factor by the urothelium was apparent.     

Towards a better understanding of involuntary detrusor activity

There is a wide spectrum of topics covered in this section. The ever-present problem of nocturia is further explored by authors from Sweden, with interesting conclusions. In addition, several papers describe various issues relating to the surgical correction of stress urinary incontinence. Finally, authors from Switzerland describe their use of sacral magnetic stimulation in non-inflammatory chronic pelvic pain syndrome. OBJECTIVES: To compare the measured variables of involuntary detrusor activity (IDA) during ambulatory cystometry (AC) in women with and with no overactive bladder symptoms, and to evaluate the correlation between these variables and symptom severity. PATIENTS AND METHODS: In all, 61 symptomatic and 39 asymptomatic women completed the Bristol Female Lower Urinary Tract Symptoms Questionnaire (BFLUTS-Q) and underwent AC. Measured variables of IDA (amplitude, duration, bladder volume and symptoms) were compared in the two cohorts. RESULTS: IDA was detected in 47 of 61 symptomatic women (77%) and in 17 of 36 (47%) controls (P < or = 0.01). The maximum IDA (defined as the highest amplitude contraction in any fill-void cycle) occurred at significantly lower volumes (328 vs 450 mL, P < or = 0.05), was of higher amplitude (26 vs 12 cm H(2)O, P = 0.14) and longer duration (83 vs 14 s, P < or = 0.05) in symptomatic women than in controls. There was coincident incontinence in 22 (36%) symptomatic women and no controls (P < or = 0.01). Discriminatory levels for clinically relevant IDA were established, and when applied retrospectively, classified 35 of 61 symptomatic women (55%) and one control (3%) as having such IDA. The correlation between symptom severity (measured by the BFLUTS-Q) and urodynamics was higher when these criteria were applied (r = 0.52 vs 0.38, P < or = 0.01). CONCLUSION: There are quantifiable differences between IDA found during AC in symptomatic and asymptomatic women. The measured variables of IDA may be useful to determine its clinical relevance, which may be indicated by contractions associated with leakage or contractions of >30 s occurring at bladder volumes of <300 mL.     

Effect of urothelium on bladder contractility in diabetic rats

AIM: It is known that physiopathological changes in diabetes affect the function of the bladder. In this study, we aimed to demonstrate the possible effects of diabetes on the urothelium during this physiopathological process. METHODS: Diabetes was induced in rats by tail vein injection of 35 mg/kg streptozotocin. Eight weeks later, intact and denuded bladder strips were prepared from these rats. Electrical field stimulation (EFS; 0.5-32 Hz), carbachol (10(-8)-10(-3) mol/L; cumulative dosage-response curves) and KCl (120 mmol/L) were used for the evaluation of the contractile responses. All responses were expressed as mg tension developed per mg of bladder tissue. Weights of rats and of their bladders, blood glucose levels, and frequency- and concentration-response curves were compared using anova, the paired t-test and the independent t-test. Differences were considered significant at P<0.05. RESULTS: Although no differences related to the weight of bladders of the control and diabetic groups were observed, there were differences in blood glucose levels and body weights between the two groups. Similarly, although there were no differences between the data obtained with EFS and KCl from tissues with intact and denuded strips in the control group, carbachol responses significantly differed between intact and denuded strips in the non-diabetic group. These differences were not observed in the diabetic group. In the control groups, in the presence of additional strips with intact urothelium placed in the medium containing denuded tissue, the differences in contractile responses between the intact control strip and the denuded strip disappeared. CONCLUSIONS: Diabetes possibly changes the interaction between the relaxant factors that are released from urothelium and muscarinic stimulation, but these interactions are not completely understood yet. Consequently, the response of the bladder to contractile stimulants is also affected. Further studies are required to reveal the mechanism by which diabetes influences the urothelium.     

Effects of potassium channel modulators on myogenic spontaneous phasic contractile activity in human detrusor from neurogenic patients

OBJECTIVE

To characterize the spontaneous contractile activity (SCA) developed by detrusor from patients with neurogenic detrusor overactivity (NDO) because the alteration of detrusor properties plays a critical role in the pathogenesis of detrusor overactivity, as well as to evaluate the role of K_ATP and K_Ca channels on this SCA because these channels regulate detrusor SCA in many species, including humans without overactive bladder (OAB).

PATIENTS AND METHODS

Human bladder samples were obtained from 44 patients undergoing cystectomy for bladder cancer with no known OAB symptoms and from 38 patients suffering from urodynamically diagnosed NDO. Detrusor strips with or without urothelium/suburothelium were mounted isometrically in organ baths filled with Krebs‐HEPES (37 °C; 95% O₂/5% CO₂). Strips were incubated with 10 µm pinacidil (K_ATP opener) followed by 10 µm glibenclamide (K_ATP blocker). In another set of experiments, strips were incubated with 30 µm NS‐1619 (BK_Ca opener) followed by 100 nm iberiotoxin (BK_Ca blocker) or with 100 nm apamin (SK_Ca blocker).

RESULTS

SCA occurred more frequently with larger amplitude and area under the curve in detrusor strips from NDO patients compared to control patients. The presence of urothelium/suburothelium did not significantly modify SCA in either patient population. Pinacidil markedly inhibited SCA of detrusor strips from control and NDO patients. This effect was reversed by glibenclamide. By contrast, NS‐1619 followed by iberiotoxin did not elicit any significant changes in SCA from NDO patients, contrary to control patients.

CONCLUSIONS

K_ATP and SK_Ca channels regulate SCA of NDO patients’ detrusor strips. By contrast, BK_Ca channels are not involved in the regulation of detrusor SCA in NDO patients, whereas they regulate SCA in control patients. These results should be considered in the development of K⁺ channels openers for the treatment of NDO. Moreover, SCA observed in vitro should be regarded as an in vitro modelling of human NDO.     

Comparative effects of angiotensin II on the contractility of muscularis mucosae and detrusor in the pig urinary bladder

To explore contractile actions of angiotensin II (ATII) on the muscularis mucosae (MM) of the bladder, ATII‐induced contractions were compared between MM and the detrusor smooth muscle (DSM) of the pig bladder by isometric tension recordings. Effects of ATII on spontaneous Ca²⁺ transients in MM were visualized using Cal‐520 fluorescence. ATII receptor type 1 (ATR1) expression in MM and DSM was also examined by immunohistochemistry. ATII (1 nM–1 μM) caused phasic contractions of MM in a concentration‐dependent manner, while ATII (10 nM–10 μM) had no or marginal effects on DSM contractility. ATII (100 nM)‐induced MM contractions had an amplitude of approximately 70% of carbachol (1 μM)‐induced or 90% of U46619 (100 nM)‐induced contractions. Candesartan (10 nM), an ATR1 blocker, prevented the contractile effects of ATII (1 nM) in MM, while ATR1 immunofluorescence was greater in MM than DSM. ATII (10–100 pM) increased the frequency but not the amplitude of spontaneous Ca²⁺ transients in MM. Both urothelium‐intact and ‐denuded MM strips developed comparable spontaneous phasic contractions, but ATII, carbachol and U46619‐induced contractions were significantly larger in urothelium‐denuded than urothelium‐intact MM strips. In conclusion, the MM appears to have a much greater sensitivity to ATII compared with DSM that could well sense circulating ATII, suggesting that MM may be the predominant target of contractile actions induced by ATII in the bladder while the urothelium appears to inhibit MM contractility.     

Bladder and upper tract urothelial cancer

PURPOSE: While there are data available indicating the incidence and prevalence of bladder and upper tract urothelial cancer, population level data on resource use, costs and patterns of care for these cancers are limited. We quantified the economic impact of caring for patients with bladder and upper tract urothelial cancer, and determined the primary drivers for such costs in the population in the United States. MATERIALS AND METHODS: The analytical methods used to generate these results have been described previously. RESULTS: An increasing proportion of patients with bladder and upper tract urothelial cancer were being treated in the outpatient setting. Most care was provided by urologists and visit frequency was directly related to disease stage. Only a small proportion of patients potentially eligible for chemotherapy, ie those with advanced disease, sought specialized care from oncologists. Office based diagnostic tests such as cytology were not commonly done, although a substantial number of patients with bladder cancer underwent cystoscopy. The use of excretory urography in these patients was decreasing, while the use of computerized tomography was increasing. Ileal conduits were the most frequently performed type of urinary diversion following cystectomy. The cystectomy rate remained unchanged for a decade. Intravesical therapy was done infrequently in patients with bladder cancer. Annual costs for treating bladder and upper urinary tract cancers were $1 billion and $64 million, respectively, in 2000. These costs represented a $164 million increase over 1994 levels, which outpaced inflation. CONCLUSIONS: The costs of treating bladder cancer increased steadily during a 6-year period despite a decrease in inpatient care. Coupled with a lack of substantial change in transurethral resection and cystectomy rates, this suggests that the primary cost drivers are increased outpatient testing, eg computerized tomography and cystoscopy, and an increase in the number of diagnosed cases. Greater focus on selective use of testing modalities, preventive care such as smoking cessation and earlier identification of patients at risk may help curtail further expenditure with regard to managing bladder and upper urinary tract cancers.     

The acute effect of magnetic stimulation of the pelvic floor on involuntary detrusor activity during natural filling and overactive bladder symptoms

OBJECTIVE: To evaluate the effect of magnetic stimulation of the pelvic floor (MSPF) on involuntary detrusor activity observed during natural filling, and on the overactive bladder symptom complex. PATIENTS AND METHODS: Eighteen women with detrusor overactivity on conventional cystometry underwent ambulatory urodynamic monitoring over two filling cycles. Fluid intake was standardized, provocative manoeuvres applied at regular intervals and symptoms documented contemporaneously. During the second filling cycle MSPF was delivered whenever the detrusor pressure increased by > 5 cmH2O. The women were subsequently treated with MSPF for 6 weeks; their lower urinary tract symptoms were assessed before and after treatment. RESULTS: Comparing the second (stimulated) cycle with the first (unstimulated) cycle, cystometric capacity was higher (373 vs 224 mL, P < 0.03). and involuntary detrusor activity of shorter duration (370 vs 427 s, P < 0.82) and lower amplitude (53 vs 63 cmH2O, P < or = 0.05). All women tolerated the procedure comfortably, but nine found it too time-consuming and withdrew. In the nine women who completed treatment there was no consistent change in overactive bladder symptoms. CONCLUSIONS: In this pilot study, MSPF during natural filling was associated with a decrease in the amplitude of involuntary detrusor contractions and a significant increase in cystometric capacity. However, MSPF had a variable effect on sensations of urgency, both acutely and after treatment, and currently there is no evidence to suggest that MSPF has an enduring effect on symptoms of the overactive bladder.     

Transabdominal ultrasonography of detrusor wall thickness in women with overactive bladder

Study Type – Diagnostic (case series)
Level of Evidence 4

OBJECTIVE

To determine the clinical usefulness of measuring detrusor wall thickness (DWT) as a noninvasive test in women with overactive bladder (OAB).

PATIENTS, SUBJECTS AND METHODS

We prospectively enrolled 122 women with dry OAB, wet OAB, and women with no OAB symptoms (control group). A 3‐day voiding diary was used to differentiate between wet and dry OAB. Transabdominal ultrasonography (TAUS) measurements of DWT were taken at bladder volumes of 250–300 mL and the maximal bladder capacity by both catheter‐ and natural‐filling. Video‐urodynamic studies (VUDS) were used to classify bladder dysfunction in 88 of the women.

RESULTS

The mean (range) age of the women was 58 (20–94) years. There were 39 ‘normal’ controls, 44 women had dry OAB, and 39 had wet OAB. Of the 88 women who had VUDS, 28 had a ‘normal’ test, 30 had increased bladder sensation (IBS), and 30 had detrusor overactivity (DO). The mean DWT at 250–300 mL among three symptomatic subgroups or urodynamic subgroups showed no significant difference by either catheter‐ or natural‐filling methods. The women with wet OAB had significantly greater DWTs than the controls at maximal bladder volume. The maximal bladder capacity was significantly greater in ‘normal’ women than in those with OAB. If we corrected maximal bladder volume to 250 mL, DWT at corrected 250 mL showed no significant difference among three symptomatic subgroups.

CONCLUSIONS

DWT measured by TAUS in women with OAB and without OAB was not different and did not differ with urodynamic status. Thus, TAUS measurement of DWT is not recommended as a useful diagnostic test for DO in women with OAB.     

Papillary urothelial neoplasm of low malignant potential: evolving terminology and concepts

PURPOSE: The most controversial aspect of the new WHO 2004/ISUP classification system is the creation of the PUNLMP diagnostic category. We discuss PUNLMP tumors and the WHO 2004/ISUP classification system with an emphasis on tumor morphology and heterogeneity, recurrence and progression rates, tumor genetics, interobserver variability and the usefulness of biomarkers and molecular diagnostic techniques for grading bladder tumors. MATERIALS AND METHODS: A literature search using PubMed was performed. All relevant literature concerning PUNLMP and the WHO 2004/ISUP grading system for urothelial neoplasms was reviewed. RESULTS: The new WHO 2004/ISUP classification reflects work in progress. Low malignant potential terminology may not reflect the true biological behavior of these tumors. Additionally, interobserver variability in making a diagnosis of PUNLMP is high despite detailed histological criteria. Urine cytopathology in the context of the WHO 2004/ISUP classification does not appear to effectively discriminate PUNLMP from low grade carcinoma. CONCLUSIONS: For practical purposes patients with PUNLMP should be treated similarly to patients with low grade, noninvasive urothelial carcinoma. It is our hope that recent advances in the molecular grading of these tumors may eventually supplant traditional morphological classification, allowing a more precise and objective assessment of the biological potential of these tumors.     

Prognostic significance of vascular and perineural invasion in urothelial bladder cancer treated with radical cystectomy

PURPOSE: Data on the prognostic significance of tumor invading lymphatic and blood vessels in bladder cancer are controversial, while little is known about perineural invasion in this tumor. We determined the prognostic value of these parameters in radical cystectomy specimens. MATERIALS AND METHODS: Slides of 283 radical cystectomy specimens obtained from 1986 to 1997 were examined retrospectively with respect to tumor invasion in lymphatic and blood vessels, and perineural spaces. This review was performed while blinded to lymph node tumor involvement or the postoperative disease course. The Kaplan-Meier probability analysis of tumor-free survival and the log rank test were used to determine the prognostic effects of vascular and perineural invasion. Multivariate analysis using the Cox proportional hazards model was also performed. RESULTS: Lymphatic, blood vessel and perineural tumor invasion were present in 54.1%, 13.1% and 47.7% of specimens, respectively. Tumor progressed in 46.3% of patients. On univariate analysis all 3 factors showed strong prognostic significance. However, on multivariate analysis only blood vessel invasion, invasion depth and regional lymph node status were independent prognostic factors (p <0.05). CONCLUSIONS: Lymph node metastases, pT classification and blood vessel invasion are independent prognostic parameters of tumor-free survival that should be used to guide patient treatment after radical cystectomy. Invasion of the blood and lymphatic vessels should be commented on separately in the pathology report.     

Induction of proliferation and differentiation of cultured urothelial cells on acellular biomaterials

OBJECTIVE: To determine the optimum conditions for the proliferation of urothelial cells, leading to the confluent coverage of large surfaces of biocompatible membranes, and for their terminal differentiation. MATERIALS AND METHODS: Porcine and human urothelial cells were cultured on different matrices under different growth conditions. Proliferative activity and the viability of cells were evaluated using fluorescent markers for nuclei and cytoplasm. Growth and differentiation were assessed by histological, histochemical and immunohistochemical methods. RESULTS: Under fibroblastic induction and supplementation of 5% fetal calf serum (FCS), urothelial cells showed more proliferation than in other conditions tested. Terminal differentiation of superficial cells was achieved by lowering the concentration of FCS to 1% at the air-liquid interface. CONCLUSIONS: The mitogenic effects of the extracellular matrix content of biological membranes and fibroblastic inductive factors are synergistic with each other, and can compensate for a low FCS concentration and the absence of other additives. Lowering the FCS concentration to 1% inhibits the proliferation of urothelial cells and permits their terminal differentiation.     

Grade progression and regression in recurrent urothelial cancer

PURPOSE: Recurrent urothelial cancers are reported to have characteristics similar to those of the primary tumor, with 10% to 25% of low grade tumors recurring as high grade disease. We determined how often grade progression and regression occur and whether abnormalities in p53 protein expression in original tumors are preserved in recurrences. MATERIALS AND METHODS: Two groups of patients treated for recurrent stages Ta/T1 urothelial bladder cancers with at least 1 tumor-free examination between the index and recurrent tumors were reviewed. Group 1 included 115 patients in whom the first available tumor was compared with the last recurrence and group 2 included 42 in whom the initial tumor was compared with the first recurrence. Immunohistochemical analysis of p53 expression was performed on a subset of 34 tumor pairs. RESULTS: In group 1, 33 grade 3 tumors (45%) recurred as grade 1 or 2 tumors, while 9 of 82 grades 1 and 2 tumors (11%) recurred as grade 3 tumors. Five of 7 group 2 grade 3 tumors (71%) recurred as grade 1 or 2 disease, while 1 of 35 grades 1 and 2 tumors (3%) recurred as grade 3 disease. In the 34 pairs studied immunohistochemically 6 of 14 grade 3 tumors recurred at lower grades. Nuclear p53 over expression occurred in 21 index tumors (12 of 14 grade 3, 8 of 17 grade 2 and 1 of 3 grade 1) and in 9 recurrences (6 of 10 grade 3, 2 of 17 grade 2 and 1 of 7 grade 1). Only 7 of 21 p53 positive and 2 of 12 p53 negative index tumors were p53 positive on recurrence. CONCLUSIONS: While progression from low to high grade occurred in less than 15% of patients, grade regression was observed in almost 50%. The loss of p53 positivity in regressing tumors indicates that these recurrences are molecularly distinct from the corresponding initial tumor.     

Bladder contractility and idiopathic detrusor instability in males

Thirty males (mean age 54 ± 13 years) with an “idiopathic” delrusor instability and fully compensated bladders (no post-micturition residuals) were assessed urodynumically at a short distance of time (3 months, on average) from the beginning of clinical symptoms. Thirty age-matched controls were also investigated. Detrusor shortening velocity was found to be increased in the unstable patients (P < 0.001), which seemed to derive from enhanced contractile capability in the presence of normal urethral resistance. Such data confirm the results of previous investigations in males with obstructive detrusor instability as well as in women with idiopathic unstable bladders. The significance ol these findings was discussed. In particular, it was suggested that detrusor instability may involve changes leading both to more excitable bladder smooth muscle cells and to an easier electrical coupling between the same cells, thus, to enhanced contractile capability. It was also suggested that if an impaired contractile function in unstable bladders may be the final result of a process of detrusor collagenosis. increased bladder contractility would rather characteri/.e an initial phase in the natural history of detrusor instability. © 1994 Wiley-Liss, Inc.