MORPHOLOGICAL ASSESSMENT OF NO-SYNTHASE DISTRIBUTION IN OVERACTIVE BLADDER AND STRESS URINE INCONTINENCE IN ANIMAL MODELS ADMINISTERED WITH EXPERIMENTAL PHARMACOCORRECTION REGIMENS.

The objective of the study was immunohistochemical evaluation of distribution of various NO synthase fractions in the structural elements of the bladder wall under stress urinary incontinence and its overactivity prior and post Mirabegron, Spasmex, Quercetin therapies and their combinations with Testosterone and Estradiol. Using the immunohistochemical method, we studied the expression of the main fractions of NO synthase in experimental models of hyperactive bladder (OAB) and stress urinary incontinence (SUI). We found that OAB and SUI were characterized by emergence of expression of the inducible fraction (iNOS) predominantly in the interstitial cells of the muscular layer of the bladder and reduced expression of endothelial (eNOS) and neuronal (nNOs) NO synthase fractions. In contrast to Spasmex, Mirabegron and Quercetin in combination with Testosterone and Estradiol contributed to stabilization of eNOS and nNOs expression already at early observation phases, and reduced the level of iNOS expression with its further disappearance in the later observation period.

Expressions of vaginal endothelial nitric oxide synthase and phosphodiesterase 5 in female sexual dysfunction: a pilot study.

INTRODUCTION AND HYPOTHESIS: The objective was to investigate the expression of endothelial nitric oxide synthase (eNOS) and phosphodiesterase (PDE) 5 in vaginal tissue of premenopausal women experiencing stress urinary incontinence (SUI) with and without sexual dysfunction. METHODS: Women presenting for treatment of SUI were screened using the Female Sexual Function Index (FSFI) and 10 were selected who met the criteria for female sexual dysfunction (FSD) and 10 asymptomatic controls. Vaginal tissue specimens were obtained from those premenopausal women aged ≥40 years who had had sexual activity ≥2 times every month for the last 6 months and who were scheduled to undergo surgery for SUI. FSD criteria was FSFI scores <18 and arousal domain scores <3. The control group had FSFI scores ≥26 and individual domain scores ≥4. The expressions of eNOS and PDE 5 were compared in the two groups using immunofluorescence staining and western blotting. RESULTS: The mean total FSFI scores were 30.4 ± 2.6 and 15.3 ± 2.3 in the control and FSD groups respectively. In immunofluorescence staining, eNOS and PDE5 were localized in the vaginal epithelium. In western blotting, the expressions of eNOS and PDE5 were significantly lower in the FSD group than in the control group (p = 0.003 and p = 0.038 respectively). CONCLUSIONS: eNOS and PDE5 in the vagina may play important roles in the pathophysiology of FSD.

Proteomic analysis of urethral protein expression in an estrogen receptor α-deficient murine model of stress urinary incontinence.

PURPOSE: The roles of estrogen receptor α (ERα) in stress urinary incontinence (SUI) remain elusive. This study was conducted to understand the molecular mechanism of ERα against SUI. METHODS: Wild-type (ERα(+/+)) and ACTB-cre ERα knockout (ERα(-/-)) female mice were generated. Urethral function and protein expression were measured. Leak point pressures (LPP) and maximum urethral closure pressure (MUCP) were assessed in mice under urethane anesthesia. After the measurements, the urethras were removed for proteomic analysis using the two-dimensional differential gel electrophoresis and liquid chromatography-mass spectrometry technology. Interaction between these ERα pathway proteins was further analyzed by using MetaCore. Lastly, Western blot and immunochemistry (IHC) were used to confirm the candidate protein expression levels and locations, respectively. RESULTS: Compared with the ERα(+/+) group, the LPP and MUCP values of the ERα(-/-) group were significantly decreased. Additionally, we identified 11 differentially expressed proteins in the urethra of ERα(-/-) female mice; five proteins were down-regulated and six were up-regulated. The majority of the ERα knockout-modified proteins were involved in muscle development, contraction, and regulation, as well as immune response (amphoterin signaling and phagocytosis), proteolysis, and cell adhesion (platelet aggregation and integrin-mediated cell-matrix adhesion). IHC and Western blot confirmed the down-regulation of tropomyosin and up-regulation of myosin in urethra. CONCLUSIONS: This is the first study to estimate protein expression changes in urethras from ERα(-/-) female mice. These changes could be related to the molecular mechanism of ERα in SUI.

Stress urinary incontinence following vaginal trauma involves remodeling of urethral connective tissue in female mice.

OBJECTIVE: The molecular mechanisms underlying stress urinary incontinence (SUI) are not clear. This study was conducted to evaluate molecular alterations in the urethras of mice with experimentally induced SUI. STUDY DESIGN: Eighteen virgin female mice were equally distributed into three groups as follows: two groups undergoing vaginal distension (VD) for 1 h with 3 mm and 8 mm dilators each, and a non-instrumented control group. Changes in leak point pressure (LPP), morphology, lysyl oxidase (LOX) expression and the metabolism of urethral connective tissue were assessed. RESULTS: The LPP was significantly decreased in the 3 mm and 8 mm VD groups compared with that in the control group. Collagen and elastin expression in the urethra was significantly decreased in the 8 mm VD group compared with that in the control group, while LOX expression was significantly enhanced. CONCLUSIONS: SUI following vaginal trauma involves over-expression of LOX and decreased synthesis of extracellular matrix components or increased proteolysis in the urethra.

Elastolytic activity in women with stress urinary incontinence and pelvic organ prolapse.

AIMS: Weakening of pelvic supportive tissues is thought to be a contributing etiology in female pelvic floor disorders such as stress urinary incontinence and/or pelvic organ prolapse (SUI/POP). Since elastin modulates the mechanical properties of supportive tissues, we examined elastase activity in vaginal tissue from women with pelvic floor dysfunction compared to asymptomatic controls, by comparing overall elastase activity, human neutrophil elastase, cathepsin K, and alpha-1 antitrypsin (a serine protease inhibitor) mRNA and protein levels. METHODS: Full-thickness peri-urethral vaginal wall tissues were collected from age and menstrual-phase matched SUI/POP and control women at the time of pelvic surgery. Elastolytic activity in the homogenized tissue was determined by the generation of amino groups from succinylated elastin. To quantify mRNA levels of each protein, quantitative competitive-PCR and confirmatory Western blot analyses were performed on the samples for human neutrophil elastase, cathepsin K, and alpha-1 antitrypsin. RESULTS: The mean elastolytic activity in vaginal tissues from the SUI/POP group was similar to that in the control group. With respect to the proteolytic enzymes, neither human neutrophil elastase nor cathepsin K differed between the two groups. However, alpha-1 antitrypsin mRNA and protein levels were significantly decreased in tissues from affected women. CONCLUSIONS: A significant decrease in alpha-1 antitrypsin expression was seen in tissues from women with SUI/POP compared to controls. This data suggest that altered elastin metabolism may contribute to the connective tissue alterations observed in pelvic floor dysfunction. Future investigations are warranted to help define the role of elastin turnover in pelvic floor dysfunction.

Differences in estrogen modulation of tissue inhibitor of matrix metalloproteinase-1 and matrix metalloproteinase-1 expression in cultured fibroblasts from continent and incontinent women.

OBJECTIVE: The purpose of this study was to investigate the effect of increasing estrogen concentrations on metalloproteinase and tissue inhibitors of metalloproteinase protein expressions in cultured pelvic fibroblasts that were obtained from continent and incontinent women. STUDY DESIGN: Periurethral vaginal wall tissues were taken from four stress incontinent and three continent premenopausal women who underwent gynecologic surgery for benign indications. Protein was extracted from these tissues, and Western blot analysis was performed to document that fibroblasts from continent and incontinent women differed with respect to metalloproteinase and tissue inhibitors of metalloproteinase production. One age-matched tissue pair was prepared for fibroblast culture. Cells were cultured with increasing concentrations of estradiol (0-500 pg/mL). Extracellular metalloproteinase and tissue inhibitors of metalloproteinase were assessed semiquantitatively with Western blotting. RESULTS: Periurethral vaginal tissues from incontinent women expressed less tissue inhibitors of metalloproteinase when compared with tissue from the control subjects; there was no difference in the expression of cleaved, active metalloproteinase protein. Tissue inhibitors of metalloproteinase expression from fibroblasts of continent women significantly increased with increasing estradiol concentrations (0-100 pg/mL, P <.05). No significant dose response was seen in fibroblasts from an incontinent woman. Metalloproteinase expression was not altered by increasing estradiol concentrations in fibroblasts from either continent or incontinent women. CONCLUSION: This preliminary in vitro study suggested that, in fibroblasts that were derived from the continent woman, tissue inhibitors of metalloproteinase protein production increases with increasing estrogen levels and that, in stress incontinent fibroblasts, no similar increase occurs. Neither group demonstrated a change in metalloproteinase production in response to varying estrogen levels, which suggests that estrogen may inhibit collagen degradation in continent women by increasing tissue inhibitors of metalloproteinase production but exerts a reduced inhibitory effect on collagenolysis in women with stress urinary incontinence.