Do extracellular matrix protein expressions change with cyclic reproductive hormones in pelvic connective tissue from women with stress urinary incontinence?

Molecular Processes in Stress Urinary Incontinence: A Systematic Review of Human and Animal Studies

Stress urinary incontinence (SUI) is a common and burdensome condition. Because of the large knowledge gap around the molecular processes involved in its pathophysiology, the aim of this review was to provide a systematic overview of genetic variants, gene and protein expression changes related to SUI in human and animal studies. On 5 January 2021, a systematic search was performed in Pubmed, Embase, Web of Science, and the Cochrane library. The screening process and quality assessment were performed in duplicate, using predefined inclusion criteria and different quality assessment tools for human and animal studies respectively. The extracted data were grouped in themes per outcome measure, according to their functions in cellular processes, and synthesized in a narrative review. Finally, 107 studies were included, of which 35 used animal models (rats and mice). Resulting from the most examined processes, the evidence suggests that SUI is associated with altered extracellular matrix metabolism, estrogen receptors, oxidative stress, apoptosis, inflammation, neurodegenerative processes, and muscle cell differentiation and contractility. Due to heterogeneity in the studies (e.g., in examined tissues), the precise contribution of the associated genes and proteins in relation to SUI pathophysiology remained unclear. Future research should focus on possible contributors to these alterations.

Molecular mechanism of extracellular matrix disorder in pelvic organ prolapses

Pelvic organ prolapses (POP) notably reduces the quality of life in elderly populations due to bladder and bowel dysfunction, incontinence, and coital problems. Extracellular matrix (ECM) disorder is a pivotal event in the progression of POP, but to date, its specific underlying mechanism remains unclear. The ligaments of patients with POP and healthy controls were collected to compare the expression of Homeobox11 (HOXA11) and transforming growth factor β (TGF-β1) via immunohistochemical analysis. HOXA11 and TGF-β1 were overexpressed or knocked down in fibroblast cells to explore their effects on the expression of collagen and matrix metalloproteinases (MMPs). HOXA11 and TGF-β1 were greatly reduced in the ligaments of patients with POP. The overexpression and downregulation of HOXA11 and TGF-β1 can mediate ECM disorder via regulating expression of collagen (Col) and MMPs. In addition, HOXA11 and TGF-β1 exerted synergistic effect on the expression of Col and MMPs. The present study identified that HOXA11 and TGF-β1 serve critical roles in mediating ECM disorders, which may be of clinical significance for the diagnosis and treatment of patients with POP.

BMMSC-sEV-derived miR-328a-3p promotes ECM remodeling of damaged urethral sphincters via the Sirt7/TGFβ signaling pathway

Background

Stress urinary incontinence (SUI) is a common and bothersome condition. Invasive surgery will always be considered after conservative treatment fails, but the rates of postoperative complications and long-term recurrence are high. Thus, a new treatment strategy is still needed. In recent years, bone marrow mesenchymal stem cells (BMMSC) have shown great promise for SUI treatment. The therapeutic effects of BMMSC on SUI are achieved mainly by paracrine pathway signaling molecules, such as small extracellular vesicles (sEV). sEV are recognized as essential mediators of cell-to-cell communication. However, the therapeutic effects and detailed mechanisms of BMMSC-derived sEV in SUI remain mostly unexplored.

Methods

The effects of BMMSC-sEV on extracellular matrix (ECM) metabolism were assessed in vitro and in vivo. In a SUI rat model, TGF-β1 signaling was examined with or without BMMSC-sEV stimulation. sEV miRNAs were deeply sequenced, and the most likely miRNAs were evaluated as mediators of the TGF-β1 signaling pathway.

Results

BMMSC-sEV enhanced the synthesis of ECM components, including elastin, collagen I, and collagen III, and improved urethral function. Furthermore, BMMSC-sEV activated TGF-β1 signaling in primary fibroblast cells and in rat urethras. Several differentially expressed miRNAs were identified in the BMMSC-sEV. Bioinformatics analysis and in vitro studies showed that BMMSC-sEV miR-328a-3p can be transferred from BMMSC to fibroblasts and can regulate the Sirt7/TGF-β1 signaling pathway.

Conclusion

BMMSC-sEV promote ECM remodeling of damaged urethral sphincters by transferring miR-328a-3p to regulate the Sirt7/TGF-β1 signaling pathway.

The role of transforming growth factor-ß (TGF-ß1) in postmenopausal women with pelvic organ prolapse: An immunohistochemical study

Objective

Aim of the study was to investigate the expression of transforming growth factor-β1 (TGF-β1), a key regulator of the extracellular matrix composition, in the uterosacral ligaments (USLs) of women with pelvic organ prolapse (POP) compared with controls. We hypothesized that the expression pattern of TGF-β1 differs between postmenopausal women with or without POP.

Methods

Under ethical approval, USL samples were obtained from postmenopausal women undergoing vaginal hysterectomy for stage two or greater pelvic organ prolapse (cases, n = 70) and from postmenopausal women without pelvic organ prolapse undergoing vaginal hysterectomy for benign indications (controls, n = 30). Immunohistochemical staining was performed from paraffin embedded tissue using anti-TGF-β1 antibodies. The expression of TGF-β1 was evaluated by the pathologist, who was blinded to all clinical data.

Results

The expression of TGF-ß1 was similar in patients with symptomatic POP (89 % positive) and in controls (90 % positive) without any signs of prolapse (p = 0.091). Age-adjusted analysis did not significantly alter these results. Regarding POP-Q stages, TGF-ß1 was significantly more frequently expressed in severe prolapse cases compared to moderate/mild cases (POP-Q stage IV versus POP-Q stage II and III; p = 0.001). No significant association could be detected between TGF-ß1 expression and age, BMI and parity in cases with POP (p > 0.05). As published previously, advanced patients’ age as well as early menopausal age remained independent risk factors associated with POP in multiple logistic regression analysis (p = 0.001; p = 0.02).

Conclusion

Although our study detected POP-Q stage related alterations in USL composition and TGF-ß1 expression, there was no significant difference in the expression of TGF-β1 in cases with or without prolapse.

Characterizing relaxin receptor expression and exploring relaxin's effect on tissue remodeling/fibrosis in the human bladder

Background

Relaxin is an endogenous protein that has been shown to have antifibrotic properties in various organ systems. There has been no characterization of relaxin’s role in the human bladder. Our objective was to characterize relaxin receptor expression in the human bladder and assess relaxin’s effect on tissue remodeling/fibrosis pathways in bladder smooth muscle cells.

Methods

Relaxin family peptide receptor 1 (RXFP1) and RXFP2 expression was assessed using quantitative reverse transcriptase-PCR (qRT-PCR) and immunohistochemistry (IHC) on primary bladder tissue. Primary human smooth muscle bladder cells were cultured and stimulated with various concentrations of relaxin. Western blot, qRTPCR, ELISA, and zymogram assays were used to analyze fibrosis/tissue remodeling pathway proteins.

Results

There was universal mRNA transcript detection and protein expression of relaxin receptors in primary bladder specimens. Immunohistochemistry demonstrated RXFP1 and RXFP2 localizing to both urothelial and smooth muscle cell layers of the bladder. 24 h of in vitro relaxin stimulation did not affect mRNA expression of selected proteins in human bladder smooth muscle cells. However, 48 h of in vitro relaxin stimulation resulted in upregulation of active (p = 0.004) and latent (p = 0.027) MMP-2 in cell lysate, and upregulation of active MMP-2 in supernatant (p = 0.04). There was a dose dependent relationship with increasing expression of MMP-2 with increasing relaxin concentration. Relaxin stimulation resulted in decreased levels of active and total TGF-β1 in supernatant and extracellular matrix (p < 0.005 with 100 ng/mL relaxin stimulation).

Conclusions

In the human bladder, relaxin receptors are expressed at the dome and trigone and localize to the urothelium and smooth muscle cell layers. Stimulation of human bladder SMCs with relaxin in vitro affects expression of MMP-2 and TGF-β1.

Observation of the effect of physical rehabilitation therapy combined with the medication on pelvic floor dysfunction

We observed the effects of physical rehabilitation therapy combined with medication on pelvic floor dysfunction (PFD). We collected the medical records of 84 maternal patients with PFD who received treatment at the Affiliated Hospital of Hebei University between May 2015 and October 2016. These patients were randomly divided into two groups, the control group (n=42) and observation group (n=42). In the control group, patients received conventional physical rehabilitation therapy while in observation group, patients received the shixiao powder combined with siwu decoction in addition to the physical rehabilitation. The therapeutic effects were compared between the two groups. The total effective rate of the observation group was 97.6%, which was significantly higher than 78.6% in the control group (P<0.05). In observation group, the index scores of pelvic floor function under rest state, such as electromyo-graphy amplitude, contraction force, coordinate strength and urine flow rate, were significantly higher than those in control group (P<0.05). The rate of Grade II perineal muscle strength in the observation group was 7.32%, which was significantly lower than 47.62% in control group (P<0.05). In observation group, the rates of Grade III and Grade IV muscle strength were respectively 43.91 and 29.26%, which were significantly higher than those in control group (P<0.05). Before the administration of treatment, there were no significant differences in the comparison of the urinary incontinence and sexual life quality of patients between the two groups (P>0.05). In observation group, after treatment, the rehabilitation effects of urinary incontinence and sexual life quality at 3 months post-delivery were significantly better than those in control group (P<0.05). Before treatment, there were no significant differences in the comparison of levels of C-reactive protein (CRP) and interleukin-10 (IL-10) between the two groups (P>0.05), however, after treatment, the levels of CRP and IL-10 of patients in observation group were significantly lower than those in control group (P<0.05). In the observation group, the incidence rate of complications (7.14%) were significantly lower than that in control group (23.81%; P<0.05). Therefore, physical rehabilitation therapy combined with the shixiao powder and siwu decoction exhibits significant efficacy in the treatment of PFD by effectively improving the pelvic floor functions, increasing perineal muscle strength, and decreasing expression levels of inflammatory factors, which can significantly ameliorate life quality and reduce the incidence rate of complications. Thus, this treatment method shows great application value in clinical practice.

Mechanism of Mechanical Trauma-Induced Extracellular Matrix Remodeling of Fibroblasts in Association with Nrf2/ARE Signaling Suppression Mediating TGF-β1/Smad3 Signaling Inhibition

Stress urinary incontinence (SUI) is a common hygienic problem affecting the quality of women's life worldwide. In this research, we revealed the involvement and regulation of extracellular matrix (ECM) remodeling, oxidative damage, and TGF-β1 signaling in the pathological mechanisms of mechanical trauma-induced SUI. We found that excessive mechanical strain significantly increased apoptosis rate, decreased cell viability and ECM production, and broke the balance of MMPs/TIMPs compared with the nonstrain control (NC) group. The expression levels of TGFβ1, p-Smad3, Nrf2, GPx1, and CAT were downregulated, the production of ROS, 8-OHdG, 4-HNE, and MDA was increased, and the nuclear translocation of Smad2/3 was suppressed after 5333 μstrain's treatment. Both mTGF-β1 pretreatment and Nrf2 overexpression could reverse mechanical injury-induced TGFβ1/Smad3 signaling inhibition and ECM remodeling, whereas mTGF-β1 had no effect on Nrf2 expression. Nrf2 overexpression significantly alleviated mechanical injury-induced ROS accumulation and oxidative damage; in contrast, Nrf2 silencing exhibited opposite effects. Besides, vaginal distention- (VD-) induced in vivo SUI model was used to confirm the in vitro results; Nrf2 knockout aggravates mechanical trauma-induced LPP reduction, ECM remodeling, oxidative damage, and TGF-β1/Smad3 suppression in mice. Therefore, we deduce that mechanical injury-induced ECM remodeling might be associated with Nrf2/ARE signaling suppression mediating TGF-β1/Smad3 signaling inhibition. This might reflect a new molecular target for SUI researches.

Potential therapeutic role of punicalagin against mechanical-trauma-induced stress urinary incontinence via upregulation of Nrf2 and TGF-β1 signaling : Effect of punicalagin on mechanical trauma induced SUI

INTRODUCTION AND HYPOTHESIS

We investigated the effect of punicalagin (PUN; 2,3-hexahydroxydiphenoyl-gallagyl-D-glucose), on mechanical-trauma-induced stress urinary incontinence (SUI) in mouse and the mechanisms underlying any effects.

METHODS

Ninety virgin female C57BL/6 mice were randomized into six groups: five groups underwent vaginal distention (VD) for 1 h and leak-point pressure (LPP) was measured on the 1st, 3rd, 7th, 14th, and 28th day following (VD groups 1 d, 3 d, 7 d, 14 d, and 28 d). The sixth group was a noninstrumented control (NC) group. Then, 75 virgin female C57BL/6 mice were randomized into five groups: a VD group (that just underwent VD) and an NC group were orally administered saline every day for 7 days; and three VD + PUN groups that underwent VD and were orally administered PUN respectively at 2.5, 5, and 10 mg/kg every day for 7 days. LPP was tested on the day 7, then all mice were sacrificed and their urethras and anterior vaginal walls harvested for Masson staining, immunohistochemistry study, Western blot analysis, and quantitative polymerase chain reaction (qPCR).

RESULTS

LPPs after VD were significantly lower than the NC group, and the LPPs of mice on days 14 and 28 day after VD were significantly higher than on the days 1, 3, and 7. PUN significantly improved VD-induced drops in LPP and alleviated VD-induced decrease of collagen I, collagen III, α-smooth muscle actin (SMA), transforming growth factor (TGF)-β1, and p-Smad3, nuclear factor-erythroid 2 p45-related factor 2 (Nrf2), and glutathione peroxidase (GPx1) protein levels, and increase of 8-hydroxydeoxyguanosine (OHdG) in urethra and anterior vaginal wall. PUN also up-regulated the expression of manganese superoxide dismutase (MnSOD), whereas protein levels of Smad 2, p-Smad2, and Smad3 were not changed.

CONCLUSIONS

PUN exerts certain therapeutic effect on mechanical-trauma-induced SUI in mice, which might be through the activation of TGF-β1/Smad3 and Nrf2/antioxidant response element (ARE) signaling activation.

Efficacy and Safety of Immuno-Magnetically Sorted Smooth Muscle Progenitor Cells Derived from Human-Induced Pluripotent Stem Cells for Restoring Urethral Sphincter Function

Human-induced pluripotent stem cells (hiPSCs)-based cell therapy holds promise for treating stress urinary incontinence (SUI). However, safety concerns, especially tumorgenic potential of residual undifferentiated cells in hiPSC derivatives, are major barriers for its clinical translation. An efficient, fast and clinical-scale strategy for purifying committed cells is also required. Our previous studies demonstrated the regenerative effects of hiPSC-derived smooth muscle progenitor cells (pSMCs) on the injured urethral sphincter in SUI, but the differentiation protocol required fluorescence-activated cell sorting (FACS) which is not practical for autologous clinical applications. In this study, we examined the efficacy and safety of hiPSC-derived pSMC populations sorted by FDA-approved magnetic-activated cell sorting (MACS) using cell-surface marker CD34 for restoring urethral sphincter function. Although the heterogeneity of MACS-sorted pSMCs was higher than that of FACS-sorted pSMCs, the percentage of undifferentiated cells dramatically decreased after directed differentiation in vitro. In vivo studies demonstrated long-term cell integration and no tumor formation of MACS-sorted pSMCs after transplantation. Furthermore, transplantation of MACS-sorted pSMCs into immunodeficient SUI rats was comparable to transplantation with FACS-sorted pSMCs for restoration of the extracellular matrix metabolism and function of the urethral sphincter. In summary, purification of hiPSC derivatives using MACS sorting for CD34 expression represent an efficient approach for production of clinical-scale pSMCs for autologous stem cell therapy for regeneration of smooth muscle tissues. Stem Cells Translational Medicine 2017;6:1158-1167.

Extracellular matrix metabolism disorder induced by mechanical strain on human parametrial ligament fibroblasts

Pelvic organ prolapse (POP) is a global health problem that may seriously impact the quality of life of the sufferer. The present study aimed to investigate the potential mechanisms underlying alterations in extracellular matrix (ECM) metabolism in the pathogenesis of POP, by investigating the expression of ECM components in human parametrial ligament fibroblasts (hPLFs) subject to various mechanical strain loads. Fibroblasts derived from parametrial ligaments were cultured from patients with POP and without malignant tumors, who underwent vaginal hysterectomy surgery. Fibroblasts at generations 3‑6 of exponential phase cells were selected, and a four‑point bending device was used for 0, 1,333 or 5,333 µ mechanical loading of cells at 0.5 Hz for 4 h. mRNA and protein expression levels of collagen type I α 1 chain (COL1A1), collagen type III α 1 chain (COL3A1), elastin, matrix metalloproteinase (MMP) ‑2 and ‑9, and transforming growth factor (TGF)‑β1 were detected by reverse transcription‑quantitative polymerase chain reaction and western blotting, respectively. Under increased mechanical strain (5,333 µ), mRNA and protein expression levels of COL1A1, COL3A1 elastin and TGF‑β1 decreased, particularly COL1A1; however, mRNA and protein expression levels of MMP‑2 and ‑9 were significantly increased, compared with the control group (0 µ strain). Following 1,333 µ mechanical strain, mRNA and protein expression levels of COL1A1, COL3A1 elastin and MMP‑2 increased, and MMP‑9 decreased, whereas no significant differences were observed in TGF‑β1 mRNA and protein expression levels. In conclusion, ECM alterations may be involved in pathogenesis of POP, with decreased synthesis and increased degradation of collagen and elastin. Furthermore, the TGF‑β1 signaling pathway may serve an important role in this process and thus may supply a new target and strategy for understanding the etiology and therapy of POP.

Smooth Muscle Progenitor Cells Derived From Human Pluripotent Stem Cells Induce Histologic Changes in Injured Urethral Sphincter

: Data suggest that myoblasts from various sources, including bone marrow, skeletal muscle, and adipose tissue, can restore muscle function in patients with urinary incontinence. Animal data have indicated that these progenitor cells exert mostly a paracrine effect on the native tissues rather than cell regeneration. Limited knowledge is available on the in vivo effect of human stem cells or muscle progenitors on injured muscles. We examined in vivo integration of smooth muscle progenitor cells (pSMCs) derived from human pluripotent stem cells (hPSCs). pSMCs were derived from a human embryonic stem cell line (H9-ESCs) and two induced pluripotent stem cell (iPSC) lines. pSMCs were injected periurethrally into urethral injury rat models (2 × 10⁶ cells per rat) or intramuscularly into severe combined immunodeficiency mice. Histologic and quantitative image analysis revealed that the urethras in pSMC-treated rats contained abundant elastic fibers and thicker muscle layers compared with the control rats. Western blot confirmed increased elastin/collagen III content in the urethra and bladder of the H9-pSMC-treated rats compared with controls. iPSC-pSMC treatment also showed similar trends in elastin and collagen III. Human elastin gene expression was not detectable in rodent tissues, suggesting that the extracellular matrix synthesis resulted from the native rodent tissues rather than from the implanted human cells. Immunofluorescence staining and in vivo bioluminescence imaging confirmed long-term engraftment of pSMCs into the host urethra and the persistence of the smooth muscle phenotype. Taken together, the data suggest that hPSC-derived pSMCs facilitate restoration of urethral sphincter function by direct smooth muscle cell regeneration and by inducing native tissue elastin/collagen III remodeling.

SIGNIFICANCE

The present study provides evidence that a pure population of human smooth muscle progenitor cells (pSMCs) derived from human pluripotent stem cells (hPSCs) (human embryonic stem cells and patient induced pluripotent stem cells) restores urethral sphincter function by two mechanisms: modulation of extracellular matrix protein metabolism in vivo and pSMC proliferation and differentiation into smooth muscle cells to regenerate the muscle layer in the lower urinary tract. These findings on the in vivo effects of human pSMCs should aid in optimizing regenerative therapies using human myoblasts.

Proliferative behavior of vaginal fibroblasts from women with pelvic organ prolapse

OBJECTIVE

Pelvic organ prolapse (POP) significantly impacts quality of life of women, especially with advancing age. Cell proliferation is a critical parameter in both normal and pathophysiological processes. We sought to examine fibroblast proliferation in premenopausal women with and without POP and menopausal women with POP, and examine whether TGF-β1, a fibroblast mitogen, could stimulate proliferation in vaginal fibroblasts from these populations.

STUDY DESIGN

Vaginal wall biopsies were obtained from asymptomatic women (controls) and women with POP (cases). Fibroblasts were cultured from these tissues. Vaginal fibroblasts were treated with or without TGF-β1. Cell proliferation rate (mitotic index) was measured with time-lapse dark-field microscopy. Cell mitosis was counted with ImageJ software after analysis of time-lapse images as Quick time movies.

RESULTS

There was no significant difference in mitotic index throughout different time points of observation between premenopausal controls and cases of similar ages. However, a significant difference in mitotic index was seen between premenopausal and menopausal cases (p=0.01), with the menopausal group exhibiting significantly lower mitotic indices. When treated with different doses of TGF-β1, premenopausal control fibroblast proliferation increased with 5ng/ml of TGF-β1 compared to non-treated fibroblasts (p=0.04). TGF-β1 stimulation did not affect fibroblasts from either premenopausal or menopausal cases.

CONCLUSIONS

Vaginal fibroblast proliferation decreases with age and this association does not appear to be affected by the presence of pelvic organ prolapse. TGF-β1 stimulation increased cell proliferation of premenopausal control fibroblasts. In contrast, there was no response seen in fibroblasts from premenopausal and menopausal cases.

Identification of protein marker in vaginal wall tissues of women with stress urinary incontinence by protein chip array

AIM

We sought to investigate protein biomarkers for stress urinary incontinence (SUI) in vaginal tissues using surface-enhanced laser desorption/ionization time-of-flight mass spectrometry (SELDI-TOF MS) and examine if this is a reliable methodology to examine proteins in small tissue specimens.

MATERIAL AND METHODS

  We compared protein expression profile of vaginal tissue from women with SUI and continent controls. A 22.6kDa peak was identified by subsequent weak cation-exchange, reverse-phase fractionation, gel electrophoresis, and trypsin digestion, then analyzed by matrix assisted laser desorption/ionization mass spectrometry (MALDI MS) and MALDI MS-MS. Biomarker identity and expression level were confirmed by Western-blotting and immunohistochemistry.

RESULTS

Expression of the 22.6kDa protein, identified as SM-22α, was significantly higher in women with SUI versus controls. A 3×3-mm tissue sample was sufficient for identification. Western-blot/immunohistochemistry confirmed the SELDI-TOS MS findings.

CONCLUSION

SM-22α, a marker for myofibroblasts, was identified as a biomarker of SUI. Differential protein profiling by SELDI-TOF MS is a powerful and reliable tool for urogynecological research as it allows us to study an array of proteins simultaneously using small tissue samples.

TGF-beta 1 is a potential regulator of vaginal tropoelastin production

INTRODUCTION AND HYPOTHESIS

Our aims were to correlate transforming growth factor (TGF)-β1 and elastin mRNA expression in the vagina of women and to measure the effects of TGF-β1 on vaginal smooth muscle cell (SMC) proliferation and tropoelastin production.

METHODS

Vaginal walls were sampled in women (n = 20). TGF-β1 and elastin mRNA expression was assessed by RT-PCR. SMC cultures were performed from vaginal wall biopsies. SMC were incubated with TGF-β1, and cell proliferation was assessed by MTT-assay. Tropoelastin production was measured by the Fastin Elastin Assay.

RESULTS

There was a significant positive correlation between TGF-β1 and elastin mRNA (r = 0.784, P < 0.01). SMC proliferation was significantly increased by 10 ng/mL TGF-β1 [relative cell number, mean ± SD, 198% ± 32% of control (P = 0.01)]. Tropoelastin production was significantly increased by TGF-β1 [mean ± SD, 645% ± 180% of control (P = 0.01)].

CONCLUSIONS

There is a positive correlation between TGF-β1 and elastin mRNA expression in the vaginal wall. In vitro, TGF-β1 increases vaginal tropoelastin production in vaginal SMC.

The effect of raloxifene, a SERM, on extracellular matrix protein expression of pelvic fibroblasts

INTRODUCTION AND HYPOTHESIS

We hypothesize that the abnormal extracellular matrix (ECM) turnover in pelvic tissues of women with prolapse may be attenuated by raloxifene. We examine the effect of raloxifene on ECM protein expression in pelvic fibroblasts.

METHODS

Pelvic fibroblasts were isolated from cases (N = 6) and controls (N = 3). Cells were treated with raloxifene. Dose-response analyses were performed by ANOVA. mRNA and protein expression of collagen I, III, MMPs, and TIMPs were determined by RT-PCR and Western blot. MMP activity was analyzed by zymography.

RESULTS

The mRNA expression of TIMP-3 and protein expression of TIMP-1 and TIMP-3 were significantly increased by raloxifene in fibroblasts from both cases and controls (P < 0.05). Collagen I, III, and MMP mRNA and protein expressions were not affected.

CONCLUSIONS

Raloxifene selectively attenuates abnormal matrix degradation by increasing inhibitors of proteases, TIMPs, in pelvic fibroblasts. This opens the possibility for SERMs to be used as preventive therapy for pelvic floor disorders.

Expression of apoptotic factors in vaginal tissues from women with urogenital prolapse

AIMS

Increased apoptotic activity in pelvic tissues may contribute to development of pelvic floor disorders. We evaluated expression of apoptotic factors (Bcl-2 family) in vaginal tissues from women with pelvic organ prolapse (POP) and how these factors correlate with severity of prolapse.

METHODS

mRNA and protein expression of anti-apoptotic and pro-apoptotic factors in vaginal tissues from subjects and controls were determined by real-time PCR and Western blot. Severity of prolapse was staged using POP-Q criteria.

RESULTS

Differential expression of Bcl-2 family factors was observed in protein rather than in gene expression. During the secretory phase, the anti-apoptotic (Bcl-2, Bcl-xl) and pro-apoptotic protein (Bax) were upregulated in controls compared to cases (P < 0.05). The ratios of Bcl-2/Bax and Bcl-2/Bad, which determine cellular sensitivity to induction of apoptosis, were higher in controls versus cases. Higher ratios indicate reduced cellular sensitivity to apoptosis. Protein expression of Bax and Bad was higher in women with severe compared to mild prolapse (P < 0.05).

CONCLUSION

Increased expression of Bad, Bax, and decreased ratios of Bcl-2/Bax, Bcl-2/Bad suggest increased apoptotic activity or sensitivity to induction of apoptosis in vaginal tissues of women with POP.

Linkage of regulators of TGF-β activity in the fetal ovary to polycystic ovary syndrome

Although not often discussed, the ovaries of women with polycystic ovary syndrome (PCOS) show all the hallmarks of increased TGF-β activity, with increased amounts of fibrous tissue and collagen in the ovarian capsule or tunica albuginea and ovarian stroma. Recent studies suggest that PCOS could have fetal origins. Genetic studies of PCOS have also found linkage with a microsatellite located in intron 55 of the extracellular matrix protein fibrillin 3. Fibrillins regulate TGF-β bioactivity in tissues by binding latent TGF-β binding proteins. We therefore examined expression of fibrillins 1-3, latent TGF-β binding proteins 1-4, and TGF-β 1-3 in bovine and human fetal ovaries at different stages of gestation and in adult ovaries. We also immunolocalized fibrillins 1 and 3. The results indicate that TGF-β pathways operate during ovarian fetal development, but most important, we show fibrillin 3 is present in the stromal compartments of fetal ovaries and is highly expressed at a critical stage early in developing human and bovine fetal ovaries when stroma is expanding and follicles are forming. These changes in expression of fibrillin 3 in the fetal ovary could lead to a predisposition to develop PCOS in later life.

Microarray analysis of differentially expressed genes in vaginal tissues in postmenopausal women. The role of stress urinary incontinence

INTRODUCTION AND HYPOTHESIS

This study aimed to explore gene expression and their regulatory mechanisms in etiology of stress urinary incontinence (SUI).

METHODS

Tissue samples were taken from the paraurethral vaginal wall from three pairs of postmenopausal, age/body mass index/parity-matched SUI, and continent women and subjected to microarray analysis using the Affymetrix GeneChip® Human Genome U133 Plus 2.0 oligonucleotide chip set. The significantly differentially expressed genes and their protein expression were confirmed by quantitative PCR and Western blot.

RESULTS

Seventy-five differentially expressed genes were listed; 31 genes were upregulated in SUI group, while 44 were downregulated. Gene metabolic pathway analysis showed that solutable N-ethylmaleimide-sensitive factor attachment protein receptor signaling pathway and neurodegenerative disorder pathway were the most predominant.

CONCLUSIONS

Apolipoprotein E, growth factor receptor-bound protein 2, Golgi SNAP receptor complex member 1, and glucosidase, beta, acid may play a neurodegenerative role in SUI development.

Alteration of vaginal elastin metabolism in women with pelvic organ prolapse

OBJECTIVE

To compare elastin metabolism in the vagina of women with and without pelvic organ prolapse and to define the regulation of this process by hormone therapy (HT).

METHODS

Eighty-seven histologically confirmed full-thickness vaginal biopsies were procured from study participants at time of surgery. Premenopausal women with no prolapse served as controls. Women with prolapse were divided into three groups: premenopausal, postmenopausal not on HT, and postmenopausal on HT. The epithelium was excised leaving the subepithelium, muscularis, and adventitia for analyses. The elastin precursor, tropoelastin, was measured by immunoblotting and mature elastin protein via a desmosine cross-link radioimmunoassay. Matrix metalloproteinases (MMPs)-2 and -9 were quantitated by gelatin zymography. Data were analyzed using Kruskal-Wallis test and post hoc analysis using the Mann-Whitney U test.

RESULTS

Tropoelastin (432%), mature elastin (55%), proMMP-9 (90%), and active MMP-9 (106%) were increased in women with prolapse relative to those in the control group while active MMP-2 (41%) was decreased. Comparison of tropoelastin and mature elastin values obtained from the same women showed them to be independently regulated (r=0.19). Interestingly, the highest amount of both proteins occurred in postmenopausal patients not on HT.

CONCLUSION

Elastin metabolism is altered in the vagina of women with prolapse relative to those in the control group, suggesting that vaginal tissue is rapidly remodeling in response to mechanical stretch. We found that elastin levels are highest in the absence of hormones.

Is lysyl oxidase-like protein-1, alpha-1 antitrypsin, and neutrophil elastase site specific in pelvic organ prolapse?

INTRODUCTION AND HYPOTHESIS

We investigated whether the expression of alpha-1 antitrypsin (ATT), neutrophil elastase (NE), and lysyl oxidase-like protein 1 (LOXL-1) vary within the vagina in subjects with pelvic organ prolapse (POP).

METHODS

Biopsies were obtained from the anterior and posterior vaginal wall of 22 women with POP (> or =stage 2 by POP-Q). The subjects were grouped by the most prominent defect: cystocele, cystocele plus uterine prolapse, and rectocele. Comparative real-time PCR, Western blotting, and NE enzyme activity assay were performed.

RESULTS

The ratio of anterior and posterior vaginal wall ATT, NE, and LOXL-1 expression varied between individuals within the same defect group.

CONCLUSIONS

ATT, NE, and LOXl-1 expression was variable among different biopsy sites in the vagina. No consistent pattern was present when the subjects were grouped by the most prominent defect. We recommend careful consideration of biopsy sites in future studies on POP to enhance reproducibility of data.

Transforming growth interacting factor expression in leiomyoma compared with myometrium

OBJECTIVE

To investigate the expression of transforming growth interacting factor (TGIF), a Smad transcriptional corepressor, in leiomyoma and matched myometrial tissue samples and the effect of TGIF overexpression in myometrial cells.

DESIGN

Experimental study.

SETTING

Tertiary university hospital.

PATIENT(S)

Uterine leiomyoma and myometrial tissues from 16 patients.

INTERVENTION(S)

None.

MAIN OUTCOME MEASURE(S)

The distribution of TGIF in leiomyoma and myometrial tissues by immunohistochemistry stain, mRNA, and protein expression levels by real-time quantitative polymerase chain-reaction (QPCR) and Western blot. Transcriptional regulation of TGIF in myometrial cells with overexpressed TGIF.

RESULT(S)

Although TGIF is present in the smooth muscle cells of the leiomyoma and the myometrium, it is not found in the extracellular matrix. The TGIF mRNA and protein expressions were statistically significantly higher in the leiomyoma compared with the matched, unaffected myometrial tissues in both phases of the menstrual cycle. There were no differences in mRNA or protein expression throughout the menstrual cycle. Overexpression of TGIF protein in myometrial cells statistically significantly suppressed up-regulation of plasminogen activator inhibitor (PAI-1) induced by TGF-beta1 treatment.

CONCLUSION(S)

Expression of TGIF is increased in leiomyoma compared with myometrium. This increase in TGIF expression is not affected by endogenous ovarian hormones. Thus, TGIF is a potential repressor of TGF-beta pathways in myometrial cells.

Expression of CD9 in frozen–thawed mouse oocytes: preliminary experience

CD9 mRNA and protein expression levels in mouse slow frozen-rapid thawed oocytes were compared with those in fresh oocytes by using comparative quantitative real time reverse transcription-PCR and semiquantitative Western blot, respectively. The expression levels of both CD9 mRNA and protein in the frozen oocytes were significantly lower than those found in the fresh oocytes.

Differences in mRNA and protein expression of small proteoglycans in vaginal wall tissue from women with and without stress urinary incontinence

BACKGROUND

To investigate changes in mRNA and protein levels of biglycan (BGN), decorin (DCN) and fibromodulin (FMOD) in vaginal wall tissue from women with stress urinary incontinence (SUI) compared to menstrual-cycle matched continent women.

METHODS

We determined mRNA expressions of BGN, DCN and FMOD by quantitative real-time PCR. They were localized in vaginal wall tissue by immunohistochemistry. We performed western blot analysis to examine protein expression.

RESULTS

BGN, DCN and FMOD co-localized with collagen and elastin in the extracellular matrix (ECM) of vaginal wall tissue from both groups. The mRNA expression of FMOD was significantly lower in cases versus controls in the proliferative phase (P = 0.03). DCN mRNA expression in cases was higher in the proliferative (P = 0.05) and secretory phases (P = 0.02) versus controls. BGN mRNA expression showed no significant differences in either phase. Protein expression of FMOD in cases was lower in the proliferative phase versus controls (six out of nine pairs), whereas DCN and BGN protein expression in the secretory phase in cases was higher (seven out of nine pairs).

CONCLUSION

BGN, DCN and FMOD expressions in vaginal wall tissue differ in women with SUI and are hormonally modulated. Differences in small proteoglycans may contribute to the altered pelvic floor connective tissues found in these women.

Increased expression of latent TGF-ß binding protein-1 and fibrillin-1 in human uterine leiomyomata

We compared latent TGF-ss binding protein-1 (LTBP-1) and fibrillin-1 (FBN-1) expression in leiomyomata and myometrium, correlated with leiomyomata size. We studied in vivo and in vitro effects of ovarian steroids using matched leiomyomata and myometrium samples from both phases of the menstrual cycle. Leiomyomata were divided into small (<or=2 cm), medium (3-5 cm) and large (>or=6 cm) groups. We validated LTBP-1 and FBN-1 expression using QPCR, western blot and immunohistochemistry. LTBP-1 and FBN-1 mRNA and protein expressions were higher in the medium-sized group compared with myometrium in the proliferative phase (P = 0.01; P = 0.01). FBN-1 mRNA expression was higher in the secretory phase (P = 0.01). LTBP-1 mRNA and protein expression was higher in the medium group compared with the small and large groups in the proliferative phase (P = 0.04; P = 0.04). No differences between groups were seen in FBN-1 expression in either phase. 17Beta-estradiol (E2) increased mRNA and protein expression of LTBP-1 and FBN-1 in cultured leiomyoma smooth muscle cells (LSMC) (P < 0.05). No change in FBN-1 and LTBP-1 expression was observed when cells were treated with E2 plus progesterone. Estrogen may be involved in LTBP-1 and FBN-1 expression in leiomyomata. Extracellular matrix metabolism may be different in medium-sized leiomyoma.