Repetitive mechanical stretch increases extracellular collagenase activity in vaginal fibroblasts

Assisted vaginal birth in 21st century: current practice and new innovations

Assisted vaginal birth rates are falling globally with rising cesarean delivery rates. Cesarean delivery is not without consequence, particularly when carried out in the second stage of labor. Cesarean delivery in the second stage is not entirely protective against pelvic floor morbidity and can lead to serious complications in a subsequent pregnancy. It should be acknowledged that the likelihood of morbidity for mother and baby associated with cesarean delivery increases with advancing labor and is greater than spontaneous vaginal birth, irrespective of the method of operative birth in the second stage of labor. In this article, we argue that assisted vaginal birth is a skilled and safe option that should always be considered and be available as an option for women who need assistance in the second stage of labor. Selecting the most appropriate mode of birth at full dilatation requires accurate clinical assessment, supported decision-making, and personalized care with consideration for the woman's preferences. Achieving vaginal birth with the primary instrument is more likely with forceps than with vacuum extraction (risk ratio, 0.58; 95% confidence interval, 0.39-0.88). Midcavity forceps are associated with a greater incidence of obstetric anal sphincter injury (odds ratio, 1.83; 95% confidence interval, 1.32-2.55) but no difference in neonatal Apgar score or umbilical artery pH. The risk for adverse outcomes is minimized when the procedure is conducted by a skilled accoucheur who selects the most appropriate instrument likely to achieve vaginal birth with the primary instrument. Anticipation of potential complications and dynamic decision-making are just as important as the technique for safe instrument use. Good communication with the woman and the birthing partner is vital and there are various recommendations on how to achieve this. There have been recent developments (such as OdonAssist) in device innovation, training, and strategies for implementation at a scale that can provide opportunities for both improved outcomes and reinvigoration of an essential skill that can save mothers' and babies' lives across the world.

Roles and mechanisms of biomechanical-biochemical coupling in pelvic organ prolapse

Pelvic organ prolapse (POP) is a significant contributor to hysterectomy among middle-aged and elderly women. However, there are challenges in terms of dedicated pharmaceutical solutions and targeted interventions for POP. The primary characteristics of POP include compromised mechanical properties of uterine ligaments and dysfunction within the vaginal support structure, often resulting from delivery-related injuries. Fibroblasts secrete extracellular matrix, which, along with the cytoskeleton, forms the structural foundation that ensures proper biomechanical function of the fascial system. This system is crucial for maintaining the anatomical position of each pelvic floor organ. By systematically exploring the roles and mechanisms of biomechanical-biochemical transformations in POP, we can understand the impact of forces on the injury and repair of these organs. A comprehensive analysis of the literature revealed that the extracellular matrix produced by fibroblasts, as well as their cytoskeleton, undergoes alterations in patient tissues and cellular models of POP. Additionally, various signaling pathways, including TGF-β1/Smad, Gpx1, PI3K/AKT, p38/MAPK, and Nr4a1, are implicated in the biomechanical-biochemical interplay of fibroblasts. This systematic review of the biomechanical-biochemical interplay in fibroblasts in POP not only enhances our understanding of its underlying causes but also establishes a theoretical foundation for future clinical interventions.

Molecular Landscape of Pelvic Organ Prolapse Provides Insights into Disease Etiology

Pelvic organ prolapse (POP) represents a major health care burden in women, but its underlying pathophysiological mechanisms have not been elucidated. We first used a case-control design to perform an exome chip study in 526 women with POP and 960 control women to identify single nucleotide variants (SNVs) associated with the disease. We then integrated the functional interactions between the POP candidate proteins derived from the exome chip study and other POP candidate molecules into a molecular landscape. We found significant associations between POP and SNVs in 54 genes. The proteins encoded by 26 of these genes fit into the molecular landscape, together with 43 other POP candidate molecules. The POP landscape is located in and around epithelial cells and fibroblasts of the urogenital tract and harbors four interacting biological processes-epithelial-mesenchymal transition, immune response, modulation of the extracellular matrix, and fibroblast function-that are regulated by sex hormones and TGFB1. Our findings were corroborated by enrichment analyses of differential gene expression data from an independent POP cohort. Lastly, based on the landscape and using vaginal fibroblasts from women with POP, we predicted and showed that metformin alters gene expression in these fibroblasts in a beneficial direction. In conclusion, our integrated molecular landscape of POP provides insights into the biological processes underlying the disease and clues towards novel treatments.

Age and/or postmenopausal status as risk factors for pelvic organ prolapse development: systematic review with meta-analysis

INTRODUCTION AND HYPOTHESIS

Age is named as a risk factor for pelvic organ prolapse (POP), despite not being the primary outcome for many observational studies. Postmenopausal status is another associated factor but has many confounders. We aimed to systematically review the role of age and/or postmenopausal status in POP development.

METHODS

Systematic review addressing age and hormones, more specifically by postmenopausal status, from inception to March 2020 in four databases (PubMed, Embase, WOS, Cochrane Library). Quality of evidence was classified by the ROBINS-I classification for non-randomized studies. Experimental studies, animal studies, studies linking age with recurrent POP and case series were excluded. Effect estimates were collected from adjusted odds ratio plus 95% confidence intervals. Significance level was 5%. A discussion exploring mechanistic factors was also included.

RESULTS

Nineteen studies (11 cross sectional, 6 cohort and 2 case control) were included for quantitative analysis. Only two studies presented a low overall risk of bias for age; most of the domains were of moderate risk. Every additional year was responsible for a 10% increase in the risk to develop POP (OR = 1.102 [1.021-1.190]; i² = 80%, random analysis, p = 0.012). This trend was confirmed when age was dichotomized into a cutoff of 35 (p = 0.035) and 50 (p < 0.001) years. Although an increase in the risk for POP was noted in postmenopausal women, this did not reach statistical significance (OR = 2.080 [0.927-4.668], i² = 0%, p = 0.076).

CONCLUSION

Age is a risk factor for POP; postmenopausal status was not statistically associated with POP, prompting the need for further studies addressing this factor.

Fully absorbable poly-4-hydroxybutyrate implants exhibit more favorable cell-matrix interactions than polypropylene

Pelvic organ prolapse (POP) is a multifactorial condition characterized by the descent of the pelvic organs due to the loss of supportive tissue strength. This is presumably caused by the decreased fibroblast function and the subsequent change in the quality of the extracellular matrix. The correction of POP using an implant intends to provide mechanical support to the pelvic organs and to stimulate a moderate host response. Synthetic polypropylene (PP) implants were commonly used for the correction of prolapse. Although they were successful in providing support, these implants have been associated with clinical complications in the long term due to substantial foreign body response and inappropriate tissue integration. The complications can be avoided or minimized by engineering a biocompatible and fully absorbable implant with optimized mechanical and structural characteristics that favor more appropriate cellular interactions with the implant. Therefore, in this study, we evaluated implants comprised of poly-4-hydroxybutyrate (P4HB), a fully absorbable material with high mechanical strength, as an alternative to PP. The P4HB implants were knitted in four unique designs with different pore shapes ranging from a more rectangular geometry- as it is in PP implant- to a rounded geometry, to determine the effect of the implant structure on the textural and mechanical properties and subsequent cell-matrix interaction. The cellular response was investigated by seeding primary vaginal fibroblasts isolated from patients with POP. P4HB favored cellular functions more than PP, as indicated by greater cell attachment and proliferation (P < 0.01), and significantly more collagen deposition (P4HB vs PP, 11.19 μg vs 6.67 μg) at 28 days culture (P < 0.05). All P4HB implants had higher strength and lower stiffness than the PP scaffold. The material and the design of the implant also influenced the behavior of vaginal fibroblasts. The aspect ratio of the vaginal POP fibroblasts cultured on the PP implant (1.61 ± 0.75) was significantly (P < 0.005) smaller than those cultured on P4HB implants (average 2.31 ± 0.09). The P4HB structure with rounded pores showed the lowest stiffness and highest fibroblast attachment and proliferation (P < 0.01). Overall, P4HB induces more matrix deposition compared to PP and knit design can further optimize cell behavior.

Comparison between transumbilical and transvaginal morcellation of a large uterus during single-port-access total laparoscopic hysterectomy

Objective

To compare the perioperative outcomes of transumbilical morcellation (TUM) and transvaginal morcellation (TVM) of a large uterus (≥500 g) during single-port-access total laparoscopic hysterectomy (SPA-TLH).

Methods

A total of 57 patients who underwent SPA-TLH for a large uterine myoma and/or adenomyosis (uterine weight ≥500 g) between March 2013 and July 2017 were included. For specimen retrieval, TUM was performed for 30 patients and TVM for 27 patients.

Results

Perioperative outcomes, including total operative time, tissue extraction time, extension of skin incision length, estimated volume of blood loss, changes in postoperative hemoglobin level, length of postoperative hospital stay, postoperative pain, and uterine weight, were compared between the 2 groups. No significant differences were observed in the baseline characteristics except for a history of cesarean section (TUM vs. TVM: 83.3% vs. 14.8%, P=0.002) and history of vaginal delivery (TUM vs. TVM: 6.7% vs. 88.8%, P=0.001). The total operative time, tissue extraction time, extension of skin incision length, estimated volume of blood loss, changes in postoperative hemoglobin level, length of postoperative hospital stay, and postoperative pain did not significantly differ between the two groups. The uterine weight was significantly higher for patients who underwent TUM than for those who had TVM (median [range]: 735 g [520–1,380 g] vs. 622 g [514–975 g]; P=0.042).

Conclusion

TUM during SPA-TLH is a feasible technique for extracting large uteri weighing ≥500 g. This procedure is suitable for patients without a history of vaginal delivery or a narrow vaginal cavity.

Early and late effects of the sequential transfixed stich technique for the treatment of the symptomatic rectocele without rectal mucosa prolapse

BACKGROUND

Different surgical techniques have been proposed for rectocele repair. However, controversial aspects exist on the best approach to use. The study aims to report the early and late outcomes of the sequential transfixed stich technique (STST) for the treatment of rectocele in the absence of mucosal prolapse.

METHODS

One hundred patients presenting a symptomatic rectocele were treated with STST from January 2010 through August 2015. Patients with mucosal prolapse were not considered eligible for STST. After a period of 24 months from surgery, all the patients were clinically evaluated with the intent to investigate the risk of recurrence of the preoperative symptoms.

RESULTS

All the patients were women (median age=54.7 years; ranges=37-75). Median discharge time was 1.5 days. One-month severe complications were: hemorrhoid thrombosis (6.0%), self-solved bleeding (6.0%), urinary retention (4.0%), anal secretion (4.0%) and urinary incontinence (1.0%). No post-operative cases of fecal incontinence were observed. Two years after surgery, 76.0% of patients reported a global improvement of the preoperative symptoms, with 73 and 35% of cases showing a reduced difficulty in the evacuation and need for digitation. Only 8.0% of patients showed a recurrence of the initial symptoms.

CONCLUSIONS

The STST is a feasible, safe, and cost-effective technique for the treatment of the rectocele without rectal mucosal prolapse. The method does not increase the risk of postoperative anal incontinence and presents a short hospital stay. STST presents long-term results in line with other transvaginal and transanal approaches.

Device to predict pelvic floor integrity during vaginal delivery: an intra- and interrater reliability study of the Epi-no distensibility measurement

Objective: To determine the test-retest reliability of the pelvic floor distensibility evaluation with Epi-no^® device.Methods: Prospective, blinded observational study with 32 women pregnant from 35 gestational weeks. An Epi-no^® balloon was inflated within the pregnant woman's vagina and the maximum circumference achieved was measured using a standard metric measuring tape. Measurements were performed twice in a day by two physiotherapists in a randomized order. Intraobserver reproducibility was obtained with another evaluation 7-14 d after the initial examination. The intraclass correlation coefficient (ICC) was used to determine the intra and interrater reliability and the respective 95% confidence intervals with an alpha level of 0.05.Results: From a total of 32 included pregnant women, 28 were analyzed; they were 29.3 (±5.97) years old, were at 37 (±1.3) weeks' gestation and presented a mean Epi-no^® circumference of 20.4 (±2.4) cm. Regarding the intraobserver analysis, examiner 1 observed a maximum circumference of 20.6 (±2.6) cm in the first evaluation and 20.2 (±2.4) cm in the second evaluation, with good reliability (ICC = 0.85). Examiner 2 observed 19.7 (±2.4) cm in the first evaluation and 21.0 (±2.0) cm in the second one, with moderate reliability (ICC = 0.58). Regarding the interobserver analysis, there was good reliability on two evaluation days, with an ICC of 0.76 and 0.82, respectively.Conclusions: Epi-no^® device is a reliable device for physiotherapists to measure pelvic floor distention during pregnancy.

Engineering and women's health: a slow start, but gaining momentum

While biomedical engineers have participated in research studies that focus on understanding aspects particular to women's health since the 1950s, the depth and breadth of the research have increased significantly in the last 15-20 years. It has been increasingly clear that engineers can lend important knowledge and analysis to address questions that are key to understanding physiology and pathophysiology related to women's health. This historical survey identifies some of the earliest contributions of engineers to exploring aspects of women's health, from the behaviour of key tissues, to issues of reproduction and breast cancer. In addition, some of the more recent work in each area is identified and areas deserving additional attention are described. The interdisciplinary nature of this area of engineering, along with the growing interest within the field of biomedical engineering, promise to bring exciting new discoveries and expand knowledge that will positively impact women's health in the near future.

Pelvic muscles' mechanical response to strains in the absence and presence of pregnancy-induced adaptations in a rat model

BACKGROUND

Maternal birth trauma to the pelvic floor muscles is thought to be consequent to mechanical demands placed on these muscles during fetal delivery that exceed muscle physiological limits. The above is consistent with studies of striated limb muscles that identify hyperelongation of sarcomeres, the functional muscle units, as the primary cause of mechanical muscle injury and resultant muscle dysfunction. However, pelvic floor muscles' mechanical response to strains have not been examined at a tissue level. Furthermore, we have previously demonstrated that during pregnancy, rat pelvic floor muscles acquire structural and functional adaptations in preparation for delivery, which likely protect against mechanical muscle injury by attenuating the strain effect.

OBJECTIVE

We sought to determine the mechanical impact of parturition-related strains on pelvic floor muscles' microstructure, and test the hypothesis that pregnancy-induced adaptations modulate muscle response to strains associated with vaginal delivery.

STUDY DESIGN

Three-month-old Sprague-Dawley late-pregnant (N = 20) and nonpregnant (N = 22) rats underwent vaginal distention, replicating fetal crowning, with variable distention volumes. Age-matched uninjured pregnant and nonpregnant rats served as respective controls. After sacrifice, pelvic floor muscles, which include coccygeus, iliocaudalis, and pubocaudalis, were fixed in situ and harvested for fiber and sarcomere length measurements. To ascertain the extent of physiological strains during spontaneous vaginal delivery, analogous measurements were obtained in intrapartum rats (N = 4) sacrificed during fetal delivery. Data were compared with repeated measures and 2-way analysis of variance, followed by pairwise comparisons, with significance set at P < .05.

RESULTS

Gross anatomic changes were observed in the pelvic floor muscles following vaginal distention, particularly in the entheseal region of pubocaudalis, which appeared translucent. The above appearance resulted from dramatic stretch of the myofibers, as indicated by significantly longer fiber length compared to controls. Stretch ratios, calculated as fiber length after vaginal distention divided by baseline fiber length, increased gradually with increasing distention volume. Paralleling these macroscopic changes, vaginal distention resulted in acute and progressive increase in sarcomere length with rising distention volume. The magnitude of strain effect varied by muscle, with the greatest sarcomere elongation observed in coccygeus, followed by pubocaudalis, and a smaller increase in iliocaudalis, observed only at higher distention volumes. The average fetal rat volume approximated 3 mL. Pelvic floor muscle sarcomere lengths in pregnant animals undergoing vaginal distention with 3 mL were similar to intrapartum sarcomere lengths in all muscles (P > .4), supporting the validity of our experimental approach. Vaginal distention resulted in dramatically longer sarcomere lengths in nonpregnant compared to pregnant animals, especially in coccygeus and pubocaudalis (P < .0001), indicating significant attenuation of sarcomere elongation in the presence of pregnancy-induced adaptations in pelvic floor muscles.

CONCLUSION

Delivery-related strains lead to acute sarcomere elongation, a well-established cause of mechanical injury in skeletal muscles. Sarcomere hyperelongation resultant from mechanical strains is attenuated by pregnancy-induced adaptations acquired by the pelvic floor muscles prior to parturition.

Transplantation of bone marrow-derived mesenchymal stem cells expressing elastin alleviates pelvic floor dysfunction

Background

Pelvic floor dysfunction (PFD) is a group of clinical conditions including stress urinary incontinence (SUI) and pelvic organ prolapse (POP). The abnormality of collagen and elastin metabolism in pelvic connective tissues is implicated in SUI and POP.

Methods

To reconstitute the connective tissues with normal distribution of collagen and elastin, we transduced elastin to bone marrow-derived mesenchymal stem cells (BMSC). Elastin-expressing BMSCs were then differentiated to fibroblasts using bFGF, which produced collagen and elastin. To achieve the sustained release of bFGF, we formulated bFGF in poly (lactic-co-glycolic acid) (PLGA) nanoparticles (NP).

Results

In an in vitro cell culture system of 7 days, when no additional bFGF was administrated, the initial PLGA-loaded bFGF NP induced prolonged production of collagen and elastin from elastin-expressing BMSCs. In vivo, co-injection of PLGA-loaded bFGF NP and elastin-expressing BMSCs into the PFD rats significantly improved the outcome of urodynamic tests. Together, these results provided an efficient model of connective tissue engineering using BMSC and injectable PLGA-loaded growth factors.

Conclusions

Our results provided the first instance of a multidisciplinary approach, combining both stem cell and nanoparticle technologies, for the treatment of PFD.

Vaginal Fibroblastic Cells from Women with Pelvic Organ Prolapse Produce Matrices with Increased Stiffness and Collagen Content

Pelvic organ prolapse (POP) is characterised by the weakening of the pelvic floor support tissues, and often by subsequent prolapse of the bladder outside the body, i.e. cystocele. The bladder is kept in place by the anterior vaginal wall which consists of a dense extracellular matrix rich in collagen content that is maintained and remodelled by fibroblastic cells, i.e. fibroblasts and myofibroblasts. Since altered matrix production influences tissue quality, and myofibroblasts are involved in normal and pathological soft tissue repair processes, we evaluated matrix production of cells derived from pre- and post-menopausal POP and non-POP control anterior vaginal wall tissues. Results showed that cells from postmenopausal POP women deposited matrices with high percentage of collagen fibres with less anisotropic orientation and increased stiffness than those produced by controls. There was a transient increase in myofibroblastic phenotype that was lost after the peak of tissue remodelling. In conclusion, affected fibroblasts from postmenopausal prolapsed tissues produced altered matrices in vitro compared to controls. Such aberrant altered matrix production does not appear to be a consequence of abnormal phenotypical changes towards the myofibroblastic lineage.

Static Mechanical Loading Influences the Expression of Extracellular Matrix and Cell Adhesion Proteins in Vaginal Cells Derived From Premenopausal Women With Severe Pelvic Organ Prolapse

INTRODUCTION

Primary human vaginal cells derived from women with severe pelvic organ prolapse (POP-HVCs) demonstrate altered cellular characteristics as compared to cells derived from asymptomatic women (control-HVCs). Using computer-controllable Flexcell stretch unit, we examined whether POP-HVCs react differently to mechanical loading as compared to control-HVCs by the expression of extracellular matrix (ECM) components, cell-ECM adhesion proteins, and ECM degrading and maturating enzymes.

METHODS

Vaginal tissue biopsies from premenopausal patients with Pelvic Organ Prolapse Quantification System stage ≥3 (n = 8) and asymptomatic controls (n = 7) were collected during vaginal hysterectomy or repair. Human vaginal cells were isolated by enzymatic digestion, seeded on collagen (COLI)-coated plates, and stretched (24 hours, 25% elongation). Total RNA was extracted, and 84 genes were screened using Human ECM and Adhesion Molecules polymerase chain reaction array; selected genes were verified by quantitative reverse transcription-polymerase chain reaction. Stretch-conditioned media (SCM) were collected and analyzed by protein array, immunoblotting, and zymography.

RESULTS

In mechanically stretched control-HVCs, transcript levels of integrins (ITGA1, ITGA4, ITGAV, and ITGB1) and matrix metalloproteinases (MMPs) 2, 8, and 13 were downregulated (P < .05); in POP-HVCs, MMP1, MMP3, and MMP10, ADAMTS8 and 13, tissue inhibitor of metalloproteinases (TIMPs) 1 to 3, ITGA2, ITGA4, ITGA6, ITGB1, contactin (CNTN1), catenins (A1 and B1), and laminins (A3 and C1) were significantly upregulated, whereas COLs (1, 4, 5, 6, 11, and 12) and LOXL1 were downregulated. Human vaginal cells massively secrete MMPs and TIMPs proteins; MMP1, MMP8, MMP9 protein expression and MMP2 gelatinase activity were increased, whereas TIMP2 decreased in SCM from POP-HVCs compared to control-HVCs.

CONCLUSIONS

Primary human vaginal cells derived from women with severe pelvic organ prolapse and control-HVCs react differentially to in vitro mechanical stretch. Risk factors that induce stretch may alter ECM composition and cell-ECM interaction in pelvic floor tissue leading to the abatement of pelvic organ support and subsequent POP development.

Effects of mechanical stretching on the morphology and cytoskeleton of vaginal fibroblasts from women with pelvic organ prolapse

Mechanical load and postmenopausal hypoestrogen are risk factors for pelvic organ prolapse (POP). In this study, we applied a 0.1-Hz uniaxial cyclic mechanical stretching (CS) with 10% elongation and 10⁻⁸ M 17-β-estradiol to vaginal fibroblasts isolated from postmenopausal women with or without POP to investigate the effects of CS and estrogen on cell morphology and cytoskeletons of normal and POP fibroblasts. Under static culture condition, POP fibroblasts exhibited lower cell circularity and higher relative fluorescence intensities (RFIs) of F-actin, α-tubulin and vimentin. When cultured with CS, all fibroblasts grew perpendicular to the force and exhibited a decreased cell projection area, cell circularity and increased cell length/width ratio; normal fibroblasts exhibited increased RFIs of all three types of cytoskeleton, and POP fibroblasts exhibited a decreased RFI of F-actin and no significant differences of α-tubulin and vimentin. After being cultured with 17-β-estradiol and CS, normal fibroblasts no longer exhibited significant changes in the cell projection area and the RFIs of F-actin and α-tubulin; POP fibroblasts exhibited no significant changes in cell circularity, length/width ratio and F-actin even with the increased RFIs of α-tubulin and vimentin. These findings suggest that POP fibroblasts have greater sensitivity to and lower tolerance for mechanical stretching, and estrogen can improve the prognosis.

A unifying neuro-fasciagenic model of somatic dysfunction - Underlying mechanisms and treatment - Part II

This paper offers an extensive review of the main fascia-mediated mechanisms underlying various therapeutic processes of clinical relevance for manual therapy. The concept of somatic dysfunction is revisited in light of the several fascial influences that may come into play during and after manual treatment. A change in perspective is thus proposed: from a nociceptive model that for decades has viewed somatic dysfunction as a neurologically-mediated phenomenon, to a unifying neuro-fascial model that integrates neural influences into a multifactorial and multidimensional interpretation of manual therapeutic effects as being partially, if not entirely, mediated by the fascia. By taking into consideration a wide spectrum of fascia-related factors - from cell-based mechanisms to cognitive and behavioural influences - a model emerges suggesting, amongst other results, a multidisciplinary-approach to the intervention of somatic dysfunction. Finally, it is proposed that a sixth osteopathic 'meta-model' - the connective tissue-fascial model - be added to the existing five models in osteopathic philosophy as the main interface between all body systems, thus providing a structural and functional framework for the body's homoeostatic potential and its inherent abilities to heal.

Functional characteristics of vaginal fibroblastic cells from premenopausal women with pelvic organ prolapse

Pelvic organ prolapse (POP) remains a great therapeutic challenge with no optimal treatment available. Tissue maintenance and remodelling are performed by fibroblasts, therefore altered cellular functionality may influence tissue quality. In this study, we evaluated functional characteristics of fibroblastic cells from tissues involved in POP. To rule out normal ageing tissue degeneration, biopsies from 18 premenopausal women were collected from the precervical region (non-POP site) after hysterectomy of 8 healthy and 10 POP cystocele cases (POP-Q stage ≥ II). Extra tissues from the prolapsed sites were taken in the POP cases to distinguish between intrinsic and acquired cellular defects. Twenty-eight primary fibroblastic cultures were studied in vitro. A contractility assay was used to test fibroblast-mediated collagen contraction. Cellular mechanoresponses on collagen-coated or uncoated substrates were evaluated by measuring matrix remodelling factors at protein or gene expression levels. No differences were found between fibroblasts from the controls and the non-POP site of the case group. Fibroblastic cells from the prolapsed site showed delayed fibroblast-mediated collagen contraction and lower production of matrix metalloproteinase-2 (MMP-2) on collagen-coated plates. On uncoated surfaces the gene MMP-2 and its tissue inhibitor of metalloproteinases-2 were up-regulated in POP site fibroblastic cells. In conclusion, fibroblastic cells derived from prolapsed tissues of patients with cystocele, display altered in vitro functional characteristics depending on the surface substrate and compared with non-prolapsed site. This implies an acquired rather than an intrinsic defect for most patients with cystocele, and should be taken into account when trying to improve treatments for POP.

Changes in tissue composition of the vaginal wall of premenopausal women with prolapse

OBJECTIVE

The objective of this study was to compare histological and biochemical features of the (normal) precervical anterior vaginal wall and the prolapsed anterior vaginal wall of women with pelvic organ prolapse (POP). These data were compared to tissue of the precervical anterior vaginal wall of age-matched controls without POP to identify possible intrinsic and acquired effects.

STUDY DESIGN

Biopsies were collected from the apex of the anterior vaginal cuff after hysterectomy from a control group of 13 premenopausal women undergoing hysterectomy for benign gynecological diseases, and a case group of 13 premenopausal women undergoing prolapse surgery (cystocele POP-Quantification stage ≥2). In women with POP an additional full-thickness vaginal wall sample was taken from the POP site during anterior colporrhaphy. Histomorphometric and biochemical analysis were performed for different components of the extracellular matrix.

RESULTS

There were no differences between case and control group in the precervical vaginal wall tissue with respect to the different components of the extracellular matrix and the biochemical parameters. However, there was a tendency toward a higher amount of collagen III and elastin, and a significant increase of smooth muscle cells and pyridinoline collagen cross-links in the POP site compared to the non-POP site of the same POP patient.

CONCLUSION

Our findings suggest that the changes seen in connective tissue in the anterior vaginal wall of women with POP are the effect, rather than the cause, of POP.

Inflammatory and tissue remodeling urinary biomarkers before and after mid urethral sling surgery for stress urinary incontinence

PURPOSE

Urinary biomarkers were measured in women at baseline and 1 year after surgery for stress urinary incontinence, and associations with clinicodemographic covariates and outcomes were analyzed.

MATERIALS AND METHODS

Preoperative and postoperative urine specimens from 150 women were assayed for inflammatory biomarkers (tumor necrosis factor-α, interferon-γ, interleukin-1β, interleukin-6, interleukin-10, interleukin-12p70, interleukin-17 and nerve growth factor) and tissue remodeling biomarkers (collagenase activity, matrix metalloproteinases-1, 2, 9 and 13, and NTx [N-telopeptide cross-linked collagen], epidermal growth factor and heparin-binding epidermal growth factor-like growth factor). Paired t-tests were used to compare changes in biomarkers during 1 year (significance p <0.05). Linear regression models correlated baseline and changes in biomarker levels with covariates (significance p ≤ 0.001). Logistic regression models, controlling for age, were used to analyze associations of baseline and changes in biomarker levels with surgical failure (significance p <0.05).

RESULTS

During 1 year interleukin-12p70 decreased (mean ± SD 0.53 ± 1.4 to 0.28 ± 0.62 pg/mg creatinine, p = 0.04) and nerve growth factor increased (0.034 ± 0.046 to 0.044 ± 0.060 pg/ml/mOsm, p = 0.03). Baseline NTx level per mg creatinine was positively associated with age and postmenopausal status (p = 0.001), and negatively associated with current estrogen use (p = 0.0001). Baseline collagenase activity per mg creatinine was positively associated with age (p = 0.001). Epidermal growth factor per mOsm, NTx per mOsm and interferon-γ per mOsm were negatively correlated with age, current estrogen use and UDI (Urogenital Distress Inventory)-irritative subscale score, respectively (p ≤ 0.001). Subjects with lower baseline NTx per mg creatinine were less likely to experience surgical failure (OR 0.49, 95% CI 0.26-0.93, p = 0.03). Changes in biomarker levels were not associated with any covariates or surgical failure.

CONCLUSIONS

Stress urinary incontinence surgery was significantly less likely to fail in women with lower baseline NTx levels. Studies are needed to validate NTx as a possible independent biomarker for stress urinary incontinence surgery outcomes.

Fibroblasts from women with pelvic organ prolapse show differential mechanoresponses depending on surface substrates

INTRODUCTION AND HYPOTHESIS

Little is known about dynamic cell-matrix interactions in the context of pathophysiology and treatments for pelvic organ prolapse (POP). This study sought to identify differences between fibroblasts from women with varying degrees of prolapse in reaction to mechanical stimuli and matrix substrates in vitro.

METHODS

Fibroblasts from the vaginal wall of three patients with POP Quantification (POP-Q) system stages 0, II, and IV were stretched on artificial polymer substrates either coated or not coated with collagen I. Changes in morphology and anabolic/catabolic compounds that affect matrix remodelling were evaluated at protein- and gene-expression levels. Statistical analysis was performed using one-way analysis of variance (ANOVA), followed by Tukey-Kramer's post hoc test.

RESULTS

POP fibroblasts show delayed cell alignment and lower responses to extracellular matrix remodelling factors at both enzymatic- and gene-expression levels compared with healthy fibroblasts.

CONCLUSION

POP fibroblasts, when compared with healthy cells, show differential mechanoresponses on two artificial polymer substrates. This should be taken into account when designing or improving implants for treating POP.

Vaginal childbirth and pelvic floor disorders

Childbirth is an important event in a woman's life. Vaginal childbirth is the most common mode of delivery and it has been associated with increased incidence of pelvic floor disorders later in life. In this article, the authors review and summarize current literature associating pelvic floor disorders with vaginal childbirth. Stress urinary incontinence and pelvic organ prolapse are strongly associated with vaginal childbirth and parity. The exact mechanism of injury associating vaginal delivery with pelvic floor disorders is not known, but is likely multifactorial, potentially including mechanical and neurovascular injury to the pelvic floor. Observational studies have identified certain obstetrical exposures as risk factors for pelvic floor disorders. These factors often coexist in clusters; hence, the isolated effect of these variables on the pelvic floor is difficult to study.

Pelvic floor disorders following vaginal or cesarean delivery

PURPOSE OF REVIEW

Pelvic floor disorders affect women of all ages and are associated with significant economic burden and poor quality of life. Current literature suggests an association between childbirth and these disorders. In this review, we summarize recent advancements in our understanding of this association.

RECENT FINDINGS

Vaginal childbirth appears to be strongly associated with stress urinary incontinence and pelvic organ prolapse. There is less evidence to suggest an association between vaginal delivery and overactive bladder symptoms. History of more than one perineal laceration increases the likelihood of developing prolapse. Similar association has not been established for episiotomy. Disruption or denervation of structural components of pelvic floor support system, particularly levator ani muscle complex, is associated with later development of pelvic floor disorders. Imbalance in homeostasis of connective tissue remodeling of the vaginal wall from overstretching during childbirth is another possible mechanism.

SUMMARY

Pelvic floor disorders represent a significant health problem affecting women of all ages. Identification of potential modifiable risk factors and advancement in understanding of the underlying pathophysiology is crucial for primary and secondary prevention of these disorders and for improvement in treatment strategies.