Fibroblast to myofibroblast differentiation is a key feature of wound-healing in soft tissues, including the vagina. Vaginal fibroblasts maintain the integrity of the vaginal wall tissues, essential to keep pelvic organs in place and avoid pelvic organ prolapse (POP). The micro-environment of vaginal tissues in POP patients is stiffer and has different extracellular matrix (ECM) composition than healthy vaginal tissues. In this study, we employed a series of matrices with known stiffnesses, as well as vaginal ECMs, in combination with vaginal fibroblasts from POP and healthy tissues to investigate how matrix stiffness and composition regulate myofibroblast differentiation in vaginal fibroblasts. Stiffness was positively correlated to production of α-smooth muscle actin (α-SMA). Vaginal ECMs induced myofibroblast differentiation as both α-SMA and collagen gene expressions were increased. This differentiation was more pronounced in cells seeded on POP-ECMs that were stiffer than those derived from healthy tissues and had higher collagen and elastin protein content. We showed that stiffness and ECM content regulate vaginal myofibroblast differentiation. We provide preliminary evidence that vaginal fibroblasts might recognize POP-ECMs as scar tissues that need to be remodeled. This is fundamentally important for tissue repair, and provides a rational basis for POP disease modelling and therapeutic innovations in vaginal reconstruction.

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.

Given that the number of surgeries for pelvic organ prolapse is expected to increase worldwide, knowledge on risk factors for prolapse recurrence is of importance for developing preventive strategies and shared decision-making. To identify risk factors for subjective and objective failure after either sacrospinous hysteropexy or vaginal hysterectomy with uterosacral ligament suspension over a period of 5 years after surgery. This was a secondary analysis of the 5-year follow-up of the SAVE-U trial. The SAVE-U trial was conducted in 4 Dutch hospitals. A total of 208 women with uterine prolapse stage ≥2 were randomized to sacrospinous hysteropexy or vaginal hysterectomy with uterosacral ligament suspension. For the current analysis, available annual 5-year follow-up data of 207 women were analyzed. Without missing values this analysis would have included 1035 measurements in total over the 5-year follow-up. Recurrences were analyzed as "events" using generalized linear mixed models because recurrences of anatomic failure and bothersome vaginal bulge symptoms fluctuated over time. The primary outcome was the composite outcome of failure defined as prolapse beyond the hymen, bothersome bulge symptoms, repeated surgery, or pessary use for recurrent prolapse. Secondary outcome measures were bothersome vaginal bulge symptoms, overall anatomic failure (Pelvic Organ Prolapse Quantification stage ≥2 in any compartment), apical compartment recurrence (Pelvic Organ Prolapse Quantification stage ≥2), anterior compartment recurrence (Pelvic Organ Prolapse Quantification stage ≥2), and posterior compartment recurrence (Pelvic Organ Prolapse Quantification stage ≥2). For the composite outcome of failure (164 events in 66 different women), statistically significant risk factors were: body mass index (odds ratio, 1.10 [per 1 kg/m²]; 95% confidence interval, 1.02-1.19; P=.02), smoking (odds ratio, 2.88; 95% confidence interval, 1.12-7.40; P=.03), and preoperative Pelvic Organ Prolapse Quantification point Ba (odds ratio, 1.23 [per 1 cm]; 95% confidence interval, 1.01-1.50; P=.04). When analyzing each surgical outcome measure separately, body mass index and Pelvic Organ Prolapse Quantification point Ba were risk factors for overall anatomic failure (462 events in 147 women; odds ratio, 1.15; 95% confidence interval, 1.07-1.25; P<.01 and odds ratio, 1.14; 95% confidence interval, 1.00-1.30; P=.05, respectively) and anterior compartment recurrence (385 events in 128 women; odds ratio, 1.11; 95% confidence interval, 1.02-1.22; P=.02 and odds ratio, 1.17; 95% confidence interval, 1.02-1.34; P=.02, respectively). Vaginal hysterectomy was a risk factor for posterior compartment recurrence when compared with sacrospinous hysteropexy (93 events in 40 women; odds ratio, 5.21; 95% confidence interval, 2.05-13.27; P<.01). Smoking was a risk factor for bothersome vaginal bulge symptoms (70 events in 41 women; odds ratio, 3.80; 95% confidence interval, 1.48-9.75; P=.01), and preoperative Pelvic Organ Prolapse Quantification stage 3 or 4 was significantly protective against bothersome bulge symptoms (odds ratio, 0.32; 95% confidence interval, 0.11-0.89; P=.03). Body mass index, smoking, and Pelvic Organ Prolapse Quantification point Ba were statistically significant risk factors for the composite outcome of failure (prolapse beyond the hymen, bothersome bulge symptoms, repeated surgery, or pessary use for recurrent prolapse) in the period of 5 years after surgery.

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.

Introduction and hypothesis The objective was to compare medium-term efficacy and safety of a partially absorbable mesh kit and native tissue repair in pelvic organ prolapse (POP). Materials and methods Women with primary POP stage ≥ II were randomized to transvaginal trocar-guided partially absorbable mesh (81 women) or native tissue repair (82 women). Primary outcome was overall anatomical success (POP < stage II) at 24 months. Secondary outcomes were composite success, global improvement, and adverse events. Results Sixty-nine (85%) of the women allocated to partially absorbable mesh underwent mesh surgery; 8 (10%) crossed over to native tissue repair and 4 women (5%) withdrew from the study. Eighty (98%) of the women allocated to native tissue repair underwent the assigned treatment and 2 (2%) withdrew. Twenty-four months later, 140 surgically treated women (89%) demonstrated an overall anatomical success of 39%; 45% (32 out of 71 women) for mesh, and 32% (22 out of 69) for native tissue repair (RR 1.4, 95% CI 0.92 to 2.2). Composite success was 88 and 73% respectively (RR: 1.1, 95% CI 0.93 to 1.4). There was global improvement in 86% (48 out of 56 women) in the mesh group and in 77% (47 out of 60 women) in the native tissue group (RR: 1.1, 95% CI 0.92 to 1.3). Four women were diagnosed with mesh exposure at 2 years (6%). Conclusion At 24 months, no significant anatomical or composite benefit of partially absorbable mesh over native tissue repair could be demonstrated in women who had been surgically treated for primary POP.

Aim: To perform a systematic review summarizing the knowledge of genetic variants, gene, and protein expression changes in humans and animals associated with urgency urinary incontinence (UUI) and to provide an overview of the known molecular mechanisms related to UUI.Methods: A systematic search was performed on March 2, 2020, in PubMed, Embase, Web of Science, and the Cochrane library. Retrieved studies were screened for eligibility. The risk of bias was assessed using the ROBINS‐I (human) and SYRCLE (animal) tool. Data were presented in a structured manner and in the case of greater than five studies on a homogeneous outcome, a meta‐analysis was performed.Results: Altogether, a total of 10,785 records were screened of which 37 studies met the inclusion criteria. Notably, 24/37 studies scored medium‐high to high on risk of bias, affecting the value of the included studies. The analysis of 70 unique genes and proteins and three genome‐wide association studies showed that specific signal transduction pathways and inflammation are associated with UUI. A meta‐analysis on the predictive value of urinary nerve growth factor (NGF) levels showed that increased urinary NGF levels correlate with UUI.Conclusion: The collective evidence showed the involvement of two molecular mechanisms (signal transduction and inflammation) and NGF in UUI, enhancing our understanding of the pathophysiology of UUI. Unfortunately, the risk of bias was medium‐high to high for most studies and the value of many observations remains unclear. Future studies should focus on elucidating how deficits in the two identified molecular mechanisms contribute to UUI and should avoid bias.