Changes in connective tissue in patients with pelvic organ prolapse—a review of the current literature

Engineered Tissue Models to Decode Host-Microbiota Interactions

A mutualistic co-evolution exists between the host and its associated microbiota in the human body. Bacteria establish ecological niches in various tissues of the body, locally influencing their physiology and functions, but also contributing to the well-being of the whole organism through systemic communication with other distant niches (axis). Emerging evidence indicates that when the composition of the microbiota inhabiting the niche changes toward a pathogenic state (dysbiosis) and interactions with the host become unbalanced, diseases may present. In addition, imbalances within a single niche can cause dysbiosis in distant organs. Current research efforts are focused on elucidating the mechanisms leading to dysbiosis, with the goal of restoring tissue homeostasis. In vitro models can provide critical experimental platforms to address this need, by reproducing the niche cyto-architecture and physiology with high fidelity. This review surveys current in in vitro host-microbiota research strategies and provides a roadmap that can guide the field in further developing physiologically relevant in vitro models of ecological niches, thus enabling investigation of the role of the microbiota in human health and diseases. Lastly, given the Food and Drug Administration Modernization Act 2.0, this review highlights emerging in vitro strategies to support the development and validation of new therapies on the market.

Progress in the genetics and epigenetics of pelvic floor disorder

Pelvic floor disorder (PFD) is a common gynecological disorder, and with the ageing of the population, PFD has a serious impact on the physical and mental health of patients and their quality of life. The most prominent of these are pelvic organ prolapse (POP) and urinary incontinence (UI), about which the etiology is still unclear, and it is urgent to explore their pathogenesis. Advances in genetics and epigenetics have provided new insights into the pathophysiology of PFD. Candidate genes and genome-wide association studies have identified susceptibility genes for POP and UI. These susceptibility genes typically promote POP by affecting pelvic floor connective tissue. The role of susceptibility genes in UI is multifactorial and includes promoting inflammation, damaging pelvic floor connective tissue, and modulating neurogenic effects. The association of epigenetic changes with POP and UI has also been investigated. DNA methylation studies have identified several important pathways associated with POP. miRNAs play an important role in the development of POP and UI, and this may be an important therapeutic direction for the future. The studies conducted so far have shown that genetic and epigenetic techniques are of great importance in exploring the etiology of PFD and that more in-depth studies are needed in the future.

Recombinant Humanized Collagen: A Promising Treatment for Pelvic Organ Prolapse via Enhanced Fibroblast Function and Angiogenesis

INTRODUCTION AND HYPOTHESIS

The treatment of pelvic organ prolapse (POP) presents significant challenges. It is important to explore safer and more effective treatment modalities. Recombinant humanized collagen (rhCol) is a promising biomaterial with excellent biocompatibility and pro-regenerative properties. Therefore, this study aims to evaluate the potential applications of rhCol in POP treatment.

METHODS

Vaginal wall tissues were collected from three non-POP and five POP patients to analyze extracellular matrix (ECM) changes via histological staining. Primary fibroblasts isolated from POP vaginal tissues were treated with rhCol III. Cell proliferation, migration, senescence, and ECM synthesis were assessed. A simulated birth injury (SBI) rat model was used to evaluate ECM remodeling following rhCol injection into the vaginal wall. Additionally, the angiogenic potential of rhCol III was examined in vivo and in vitro.

RESULTS

POP patient tissues and fibroblasts exhibited lower expression levels of type I and III collagen compared to non-POP samples. At a 1 mg/ml concentration, rhCol III promoted fibroblast proliferation and migration, reduced cellular senescence, and enhanced ECM synthesis. In the vaginal wall, the expression of COL1A1 and COL3A1 in the rhCol group was significantly higher than that in the SBI group, with a marked increase in the levels of CD31, CD34, and VEGFA. Furthermore, rhCol III improved the proliferation, migration, and tubule formation capacities of HUVECs.

CONCLUSIONS

rhCol III may promote ECM remodeling in an injured vaginal wall by restoring fibroblast function and stimulating angiogenesis, offering a novel biomaterial-based strategy for POP treatment.

3D Printed Mesh Geometry Modulates Immune Response and Interface Biology in Mouse and Sheep Model: Implications for Pelvic Floor Surgery

Pelvic organ prolapse (POP) is a highly prevalent yet neglected health burden for women. Strengthening the pelvic floor with bioactive tissue-engineered meshes is an emerging concept. This study investigates tissue regenerative design parameters, including degradability, porosity, and angulation, to develop alternative degradable melt electrowritten (MEW) constructs for surgical applications of POP. MEW constructs were fabricated in hierarchical geometries by two-way stacking of the fibers with three different inter layer angles of 90°, 45°, or 22.5°. Implants printed at 22.5° have higher tensile strength under dry conditions and show better vaginal fibroblast (VF) attachment in vitro. In vivo assessment using preclinical mouse and ovine models demonstrates more effective degradation and improved tissue integration in 22.5° angular meshes compared to 90° and 45° meshes, with evidence of neo-collagen deposition within implants at 6 weeks. The pattern and geometry of the layered MEW implants also influence the foreign body response, wherein the anti-inflammatory phenotype shows a greater ratio of anti-inflammatory CD206+ M2 macrophages/pro-inflammatory CCR7+ M1 macrophages. This presents an attractive strategy for improving the design and fabrication of next-generation vaginal implants for pelvic reconstructive surgery.

Risk factors for pelvic organ prolapse, a case-control study in a tertiary hospital in Iran

BACKGROUND

Pelvic organ descent is a common gynecological disorder called pelvic organ prolapse (POP). Conservative care and surgical repair are women's primary treatments for pelvic organ prolapse. Modifying risk factors is a crucial keystone to reducing its prevalence.

METHODS

This unmatched case-control study was conducted at a Tehran referral hospital (June 15 to September 10, 2020) and involved 287 participants (139 cases, 148 controls). Structured questionnaires gathered socio-demographic, obstetric, health, and lifestyle data. Analyses encompassed univariate and multivariate logistic regression.

RESULTS

Among cases, 69 (49.6%) had anterior prolapse, 46 (33.1%) had posterior prolapse, and 24 (17.3%) experienced complete prolapse. The mean age of participants with POP was 62.7 ± 10.7 years compared to 44.5 ± 12.7 years for controls. Risk factors significantly associated with POP included higher BMI (28.01 ± 4.7 vs 26.18 ± 4.6; p = 0.002), gravidity (4.49 ± 2.89 vs 2.18 ± 1.63; p < 0.001), vaginal deliveries (3.60 ± 2.07 vs 1.03 ± 1.57; p < 0.001), prolonged labor (12.2% vs 2.7%; OR: 4.91, 95% CI: 1.61-14.99), and comorbidities such as diabetes mellitus (30.2% vs 8.8%; OR: 4.49, 95% CI: 2.29-8.83) and hypertension (34.5% vs 6.8%; OR: 7.28, 95% CI: 3.50-15.12). Protective factors included higher education levels and a history of cesarean delivery (mean cesarean count: 0.31 ± 0.72 vs 0.78 ± 0.88; p < 0.001).

CONCLUSIONS

This study highlights key risk factors for POP among Iranian women, emphasizing the need for targeted preventive strategies. Public health interventions addressing these factors may reduce the burden of POP in developing regions.

A systematic review of uterine cervical elongation and meta-analysis of Manchester repair

OBJECTIVE

This review aims to consolidate current research on cervical elongation, a common but often overlooked complication in pelvic organ prolapse and hysteropexy procedures. It seeks to define, diagnose, and manage cervical elongation, aiming to establish standardized criteria and strategies to enhance clinical outcomes for this condition.

DATA SOURCES

A comprehensive search of the PubMed/MEDLINE, Cochrane Library, and Web of Science databases was executed utilizing the keywords: "cervical elongation," "long cervix uteri," "Manchester," and "cervical amputation". Data were gathered and organized in an Excel spreadsheet, with the analysis conducted according to each category, methodology, or reference range.

STUDY ELIGIBILITY CRITERIA

All types of study designs with full-text availability, including randomized controlled trials, cohort studies, case-control studies, case reports, and systematic reviews, were considered for inclusion. Included studies were fully accessible in English and focused on the topic of interest. Exclusions were made for studies addressing cervical elongation not pertinent to pelvic organ prolapse, and publications such as secondary analyses, case reports, literature reviews, and opinion papers.

RESULTS

Out of 108 relevant studies, only 63 defined their inclusion criteria; of these, 57 were utilized for the narrative review and 8 were used in a meta-analysis comparing the Manchester operation with vaginal hysterectomy. Magnetic Resonance Imaging offers the highest sensitivity in measuring cervical elongation, its practical limitations and high cost necessitate the use of the more feasible Pelvic Organ Prolapse Quantification System (POP-Q), particularly effective for stage 2 and 3 prolapse cases. The POP-Q point C emerges as a pivotal marker for identifying cervical elongation, with specific measurements indicating the condition's presence. The Manchester-Fothergill procedure presents a viable management option for isolated cervical elongation, showing fewer complications and comparable recurrence rates to vaginal hysterectomy.

CONCLUSION

This review highlights the diagnostic and definitional diversity of cervical elongation within populations experiencing pelvic organ prolapse. It emphasizes the critical role of preoperative cervical evaluation, particularly in patients with uterine descensus for selecting the most appropriate surgical intervention.

The difference in extracellular matrix metabolism in women with and without pelvic organ prolapse: A systematic review and meta-analysis

BACKGROUND

Studies on the changes of extracellular matrix (ECM) in pelvic organ prolapse (POP) are still controversial.

OBJECTIVE

To identify the changes in the ECM in POP patients.

SEARCH STRATEGY

Comprehensive searching in Embase, PubMed, Web of Science and the Cochrane Library was carried out until 23 February 2023.

SELECTION CRITERIA

Studies comparing the protein levels of ECM-related components between women with and without POP.

DATA COLLECTION AND ANALYSIS

Quality and risk of bias were assessed using the Agency for Healthcare Research and Quality assessment. Indicators were pooled with random or fixed effect meta-analysis based on heterogeneity and sub-grouped analysed by the biopsy site.

MAIN RESULTS

Thirty cross-sectional studies were included, comprising 840 POP cases and 755 controls. Overall results showed that the expression of type III collagen (COLIII) and several matrix metalloproteinases (MMP-1, -2 and -9) were increased, whereas those of type I collagen (COLI), and tissue inhibitor of matrix metalloproteinase-1 (TIMP-1) were decreased in patients with POP. Subgroup analysis showed that the expression of COLIII in the anterior vaginal wall (AVW) and COLIII, MMP-2 and -9 in the uterosacral ligament (USL) were consistent with the overall results. However, the expression of COLI and MMP-1 in the AVW showed no difference and the expression of COLI and MMP-1 in the USL is still controversial based on current studies.

CONCLUSIONS

Patients with POP have lower expression of COLI and TIMP-1 and higher expression of COLIII and MMPs compared with non-POP cases, but further studies are required to investigate in specified anatomical sites.

Promoting cell proliferation and collagen production with ascorbic acid 2-phosphate-releasing poly(l-lactide-co-ε-caprolactone) membranes for treating pelvic organ prolapse

Pelvic organ prolapse (POP) afflicts millions of women globally. In POP, the weakened support of the pelvic floor results in the descent of pelvic organs into the vagina, causing a feeling of bulging, problems in urination, defaecation and/or sexual function. However, the existing surgical repair methods for relapsed POP remain insufficient, highlighting the urgent need for more effective alternatives. Collagen is an essential component in pelvic floor tissues, providing structural support, and its production is controlled by ascorbic acid. Therefore, we investigated novel ascorbic acid 2-phosphate (A2P)-releasing poly(l-lactide-co-ε-caprolactone) (PLCLA2P) membranes in vitro to promote cell proliferation and extracellular matrix protein production to strengthen the natural support of the pelvic fascia for POP applications. We analysed the mechanical properties and the impact of PLCLA2P on cellular responses through cell culture analysis using human vaginal fibroblasts (hVFs) and human adipose-derived stem/stromal cells (hASCs) compared to PLCL. In addition, the A2P release from PLCLA2P membranes was assessed in vitro. The PLCLA2P demonstrated slightly lower tensile strength (2.2 ± 0.4 MPa) compared to PLCL (3.7 ± 0.6 MPa) for the first 4 weeks in vitro. The A2P was most rapidly released during the first 48 h of in vitro incubation. Our findings demonstrated significantly increased proliferation and collagen production of both hVFs and hASCs on A2P-releasing PLCLA2P compared to PLCL. In addition, extracellular collagen Type I fibres were detected in hVFs, suggesting enhanced collagen maturation on PLCLA2P. Moreover, increased extracellular matrix protein expression was detected on PLCLA2P in both hVFs and hASCs compared to plain PLCL. In conclusion, these findings highlight the potential of PLCLA2P as a promising candidate for promoting tissue regeneration in applications aimed for POP tissue engineering applications.

Obstetric risk factors for levator ani muscle avulsion: A systematic review and meta-analysis

OBJECTIVES

Women have a 11% lifetime risk of undergoing surgery for vaginal prolapse. Levator ani muscle (LAM) avulsion is one etiological factor associated with primary and recurrent pelvic organ prolapse. Pelvic organ prolapse has been shown to greatly affect the quality of life and well-being of women. Conduct a meta-analysis identifying risk factors associated with LAM avulsion recognised on transperineal ultrasound (TPUS) or magnetic resonance imaging (MRI) in primiparous women after vaginal birth.

STUDY DESIGN

OVID Medline, Embase and the Cochrane Library from inception to January 2021 were searched. Review Manager 5.3 (The Cochrane Collaboration) was used to analyse data. Odds ratios (OR) with 95% confidence intervals (95% CIs) were calculated. The heterogeneity among studies was calculated using the I2statistic.

RESULTS

Twenty-five studies were eligible for inclusion (n = 9333 women). Major LAM avulsion was diagnosed in an average of 22 % (range 12.7-39.5 %) of cases. Twenty-two studies used TPUS and three used MRI to diagnose avulsion. Modifiable and non-modifiable risk factors were identified. Significant predictors identified were forceps (OR 6.25 [4.33 - 9.0]), obstetric anal sphincter injuries (OR 3.93 [2.85-5.42]), vacuum (OR 2.41 [1.40-4.16]), and maternal age (OR 1.06 [1.02-1.10]).

CONCLUSIONS

This is the first meta-analysis of both modifiable and non-modifiable risk factors associated with LAM avulsion. This information could be used to develop a clinically applicable risk prediction model to target postnatal women at risk of LAM avulsion with a view to prevent the onset of pelvic floor organ prolapse.

An Improved Understanding of the Pathophysiology of Pelvic Organ Prolapse: A 3D In Vitro Model under Static and Mechanical Loading Conditions

The suboptimal outcomes of pelvic organ prolapse (POP) surgery illustrate the demand for improved therapies. However, their development is hampered by the limited knowledge on the cellular pathophysiology of POP. Current investigations, that are limited to tissues and 2D in vitro models, provide highly inconclusive results on how the extracellular matrix (ECM) metabolism and fibroblasts are affected in POP. This study uses a physiologically relevant 3D in vitro model to investigate the cellular pathophysiology of POP by determining the differences between POP and non-POP fibroblasts on ECM metabolism, proliferation, and fibroblast-to-myofibroblast (FMT) transition. This model, based on the synthetic and biomimetic polyisocyanide hydrogel, enables the incorporation of mechanical loading, which simulates the forces exerted on the pelvic floor. Under static conditions, 3D cultured POP fibroblasts are less proliferative, undergo FMT, and exhibit lower collagen and elastin contents compared to non-POP fibroblasts. However, under mechanical loading, the differences between POP and non-POP fibroblasts are less pronounced. This study contributes to the development of more comprehensive models that can accurately mimic the POP pathophysiology, which will aid in an enhanced understanding and may contribute to improved therapies in the future.

Early growth response 2, a novel target of pelvic organ prolapse, is highly expressed in anterior vaginal wall tissues with pelvic organ prolapse

Pelvic organ prolapse (POP) is a common disorder among women that negatively affects women's quality of life. Early growth response 2 (EGR2) is a transcription factor that regulates cell growth. The present study aimed to explore the role of EGR2 in POP progression and provided a new target for the treatment and prevention of POP. Firstly, we extracted primary vaginal anterior wall fibroblasts from POP tissues and non-POP tissues and then constructed an EGR2-silencing lentivirus for further study. Immunoblotting, qPCR, TUNEL assay, CCK-8 assay, dual luciferase assay, and ELISA assay were carried out. EGR2 expression was much higher in POP tissues than in control tissues, and EGR2 expression positively correlated with cytokine signaling 3 (SOCS3) expression. Knockdown of EGR2 increased cell proliferation, upregulated PCNA expression, and reduced apoptosis in POP fibroblasts. Moreover, we found that the knockdown of EGR2 increased COL1A1, COL3A1, and Elastin expression and decreased MMP2 and MMP9 activities, and knockdown of EGR2 increased TGF-β/Smad pathway activity in POP fibroblasts. Interestingly, the results of dual luciferase assay demonstrated that EGR2 was able to increase SOCS3 transcriptional activity. EGR2 knockdown alleviated the apoptosis of POP fibroblasts by reducing SOCS3 expression and improving the proliferation and collagen synthesis of POP fibroblasts. Overall, our study illustrated that EGR2 was highly expressed in POP tissues, and knockdown of EGR2 alleviated apoptosis and reduced matrix degradation in POP fibroblasts. This study might provide a new insight into the pathogenesis of POP.

Diabetic Pneumopathy- A Novel Diabetes-associated Complication: Pathophysiology, the Underlying Mechanism and Combination Medication

BACKGROUND

The "diabetic lung" has been identified as a possible target organ in diabetes, with abnormalities in ventilation control, bronchomotor tone, lung volume, pulmonary diffusing capacity, and neuroadrenergic bronchial innervation.

OBJECTIVE

This review summarizes studies related to diabetic pneumopathy, pathophysiology and a number of pulmonary disorders including type 1 and type 2 diabetes.

METHODS

Electronic searches were conducted on databases such as Pub Med, Wiley Online Library (WOL), Scopus, Elsevier, ScienceDirect, and Google Scholar using standard keywords "diabetes," "diabetes Pneumopathy," "Pathophysiology," "Lung diseases," "lung infection" for review articles published between 1978 to 2023 very few previous review articles based their focus on diabetic pneumopathy and its pathophysiology.

RESULTS

Globally, the incidence of diabetes mellitus has been rising. It is a chronic, progressive metabolic disease. The "diabetic lung" may serve as a model of accelerated ageing since diabetics' rate of respiratory function deterioration is two to three-times higher than that of normal, non-smoking people.

CONCLUSION

Diabetes-induced pulmonary dysfunction has not gained the attention it deserves due to a lack of proven causality and changes in cellular properties. The mechanism underlying a particular lung illness can still only be partially activated by diabetes but there is evidence that hyperglycemia is linked to pulmonary fibrosis in diabetic people.

Injectable polyisocyanide hydrogel as healing supplement for connective tissue regeneration in an abdominal wound model

In pelvic organ prolapse (POP) patients, the uterus, bladder and/or rectum descends into vagina due to weakened support tissues. High recurrence rates after POP surgery suggest an urgent need for improved surgical outcomes. Our aim is to promote connective tissue healing that results in stimulated tissue support functions by surgically applying a hydrogel functionalized with biological cues. We used known vaginal wound healing promoting factors (basic fibroblast growth factor, β-estradiol, adipose-derived stem cells) in the biomimetic and injectable polyisocyanide (PIC) hydrogel, which in itself induces regenerative vaginal fibroblast behavior. The regenerative capacity of injected PIC hydrogel, and the additional pro-regenerative effects of these bioactive factors was evaluated in abdominal wounds in rabbits. Assessment of connective tissue healing (tensile testing, histology, immunohistochemistry) revealed that injection with all PIC formulations resulted in a statistically significant stiffness and collagen increase over time, in contrast to sham. Histological evaluation indicated new tissue growth with moderate to mild immune activity at the hydrogel - tissue interface. The results suggest that PIC injection in an abdominal wound improves healing towards regaining load-bearing capacity, which encourages us to investigate application of the hydrogel in a more translational vaginal model for POP surgery in sheep.

A comprehensive evaluation of spontaneous pelvic organ prolapse in rhesus macaques as an ideal model for the study of human pelvic organ prolapse

Pelvic organ prolapse (POP) seriously affects a woman's quality of life, and the treatment complications are severe. Although new surgical treatments are being developed, the host tissue responses and safety need to be evaluated in preclinical trials. However, there is a lack of suitable animal models, as most quadrupeds exhibit different structural and pathological changes. In this study, 72 elderly rhesus macaques (Macaca mulatta) were physically examined, and the incidence of spontaneous POP was similar to that in humans. The vaginal wall from five control monkeys and four monkeys with POP were selected for further analysis. Verhoeff-van Gieson staining showed that elastin content decreased significantly in monkeys with POP compared with control samples. Immunohistological staining revealed that the smooth muscle bundles in monkey POP appeared disorganized, and the number of large muscle bundles decreased significantly. The collagen I/III ratio in monkey POP also significantly decreased, as revealed by Sirius Red staining. These histological and biochemical changes in monkeys with POP were similar to those in humans with POP. Moreover, we generated a single-cell transcriptomic atlas of the prolapsed monkey vagina. Cross-species analysis between humans and monkeys revealed a comparable cellular composition. Notably, a differential gene expression analysis determined that dysregulation of the extracellular matrix and an immune disorder were the conserved molecular mechanisms. The interplay between fibroblasts and macrophages contributed to human and monkey POP. Overall, this study represents a comprehensive evaluation of spontaneous POP in rhesus macaques and demonstrates that monkeys are a suitable animal model for POP research.

Association between the rs1036819 polymorphism of the ZFAT gene and pelvic organ prolapse: a case-control study

INTRODUCTION AND HYPOTHESIS

The identification of risk factors for pelvic organ prolapse (POP) would contribute to planning prevention strategies. This study tests the hypothesis that the rs1036819 polymorphism in the ZFAT gene is associated with POP and investigates other risk factors for prolapse development.

METHODS

A case-control study was carried out including 826 postmenopausal women divided into POP cases (stages III and IV) and controls (stages 0 and I), assessed by anamnesis, examination, and peripheral blood samples. DNA was extracted from blood and genotyped by real-time RT-PCR. We used logistic regression models for the association analyses of variables, with p < 0.05 for significance.

RESULTS

Five hundred and sixty-eight women were evaluated (315 POP and 253 controls). The minor allele C was found in 19.3% of our sample and the genotype frequencies of AA, AC, and CC were similar in both groups. Age (OR 1.09, 95% CI 1.06-1.13), number of pregnancies (OR 1.23, 95% CI 1.08-1.41), history of one vaginal delivery (OR 3.39, 95% CI 1.38-8.33) or two or more (OR 2.51, 95% CI 1.04-6.07), weight of the largest newborn (OR 1.0001, 95% CI 1-1.001), and family history of POP (OR 2.27, 95% CI 1.24-4.13) were independent risk factors for POP, whereas one cesarean section (OR 0.48, 95% CI 0.27-0.88) or two or more (OR 0.14, 95% CI 0.05-0.38) were protective.

CONCLUSIONS

No association was detected between the rs1036819 polymorphism of the ZFAT gene and advanced POP. Age, number of pregnancies, at least one vaginal delivery, weight of the newborn, and POP family history were independent risk factors for POP.

The Effect of Growth Factors on Vaginal Wound Healing: A Systematic Review and Meta-analysis

Surgical outcomes of pelvic organ prolapse (POP) surgery are poor, resulting in a 20% recurrence risk. Following the hypothesis that impaired wound healing is the main determinant of recurrent POP, growth factors have the potential to promote wound healing and may improve surgical outcomes. In this study, we systematically reviewed the effect of growth factors on vaginal wound healing in both in vitro and animal studies. For each independent comparison, the standardized mean difference and 95% CI were calculated using the Hedges' g correction. Of the 3858 retrieved studies, seven studies were included, of which six were included in meta-analysis (three in vitro studies and four in vivo studies). In vitro, basic fibroblast growth factor (bFGF) promotes proliferation, differentiation, and collagen types I and III production. Epidermal growth factor stimulates proliferation and connective tissue growth factor promotes Tenascin-C expression. These effects, however, are less pronounced in vivo; only bFGF slightly promotes collagen production. The review shows that growth factors, particularly bFGF, are able to promote vaginal wound healing in vitro. The uncertain in vivo findings suggest that preclinical models should be improved. The ultimate goal is to develop effective growth factor-supplemented therapies that improve surgical outcomes for POP.

Quantification of senescence-associated secretory phenotype proteins in the vaginal secretions of pre- and postmenopausal women with and without prolapse

Objectives

Cellular senescence has been proposed as a pathophysiologic driver in the development of pelvic organ prolapse (POP), especially during aging. In this study, we aimed to determine if markers of cell senescence can be quantified from vaginal secretions collected from pre- and postmenopausal women with and without POP.

Methods

Vaginal swabs were collected from 81 women in four groups: premenopausal with (pre-P) and without prolapse (pre-NP), and postmenopausal with (post-P) and without prolapse (post-NP). Multiplex immunoassays (MagPix) were then used to detect and quantify the presence of 10 SASP proteins in vaginal secretions.

Results

The total protein concentration of vaginal secretions differed significantly among the four groups (P = 0.003) with highest mean concentrations in pre-P [16, interquartile range (IQR) = 4.6, 38.3 μg/μL] and lowest mean concentrations in post-P (4.4, IQR = 2.6, 7 μg/μL). The normalized concentrations of several SASP markers differed significantly among groups, with the highest concentrations being seen in the post-P group, and the lowest concentrations being in the pre-NP group. Using these key markers, we then constructed receiver-operator curves to determine the relative sensitivity and specificity of these markers in predicting prolapse.

Conclusions

In this study, we found that SASP proteins can be detected and quantified in vaginal secretions. Several of these markers were differentially expressed among the four groups studied, with the highest normalized concentrations of SASP markers found among postmenopausal women with prolapse. Overall, the data support the theory that senescence is associated with prolapse during aging but that other factors may be important in younger women who develop POP before menopause.

Nonoperative Management of Pelvic Organ Prolapse

Pelvic organ prolapse (POP) is defined as the descent of one or more of the anterior, posterior, or apical vagina. It is a common condition, with up to 50% of women having prolapse on examination in their lifetimes. This article provides an overview of the evaluation and discussion of nonoperative management of POP for the obstetrician-gynecologist (ob-gyn), with consideration of recommendations from the American College of Obstetricians and Gynecologists, the American Urogynecologic Society, and the International Urogynecological Association. The initial evaluation of POP requires a history documenting whether the patient is experiencing symptoms and what they are, and discovery of which symptoms they believe are attributable to prolapse. Examination determines the vaginal compartment(s) and to what degree prolapse exists. In general, only patients who have symptomatic prolapse or medical indication should be offered treatment. Although surgical options exist, all patients who are symptomatic and desire treatment should be offered nonsurgical treatment first, including pelvic floor physical therapy or a pessary trial. Appropriateness, expectations, complications, and counseling points are reviewed. Educational opportunities between the patient and the ob-gyn include disentangling common beliefs that the bladder is dropping or that concomitant urinary or bowel symptoms are necessarily caused by prolapse. Improving patient education can lead to a better understanding of their condition and better alignment of treatment goals and expectations.

Exosomes derived from mesenchymal stromal cells: a promising treatment for pelvic floor dysfunction

Pelvic floor dysfunction (PFDs), which include pelvic organ prolapse (POP), stress urinary incontinence (SUI) and anal incontinence (AI), are common degenerative diseases in women that have dramatic effects on quality of life. The pathology of PFDs is based on impaired pelvic connective tissue supportive strength due to an imbalance in extracellular matrix (ECM) metabolism, the loss of a variety of cell types, such as fibroblasts, muscle cells, peripheral nerve cells, and oxidative stress and inflammation in the pelvic environment. Fortunately, exosomes, which are one of the major secretions of mesenchymal stromal cells (MSCs), are involved in intercellular communication and the modulation of molecular activities in recipient cells via their contents, which are bioactive proteins and genetic factors such as mRNAs and miRNAs. These components modify fibroblast activation and secretion, facilitate ECM modelling, and promote cell proliferation to enhance pelvic tissue regeneration. In this review, we focus on the molecular mechanisms and future directions of exosomes derived from MSCs that are of great value in the treatment of PFD.

Conservative interventions may have little effect on reducing diastasis of the rectus abdominis in postnatal women - A systematic review and meta-analysis

BACKGROUND

Diastasis of the rectus abdominis muscle (DRAM) commonly occurs in pregnancy and postnatally. Physiotherapists routinely guide women in its management, although the effectiveness of these treatments is unknown.

OBJECTIVES

To determine the effectiveness of conservative interventions to reduce the presence and width of DRAM in pregnant and postnatal women.

DATA SOURCES

EMBASE, Medline, CINAHL, PUBMED, AMED and PEDro searched until August 2021.

STUDY SELECTION/ELIGIBILITY

Randomised control trials examining any conservative interventions to manage DRAM during the ante- and postnatal periods were included.

STUDY APPRAISAL AND SYNTHESIS METHODS

Methodological quality was assessed using the Cochrane Risk of Bias 2 tool. Meta-analyses were performed using a random effects model to calculate mean differences (MD) and odds ratios (OR). A GRADE approach determined the certainty of evidence for each meta-analysis.

RESULTS

Sixteen trials with 698 women during the postnatal period were included. No trials evaluated interventions during the antenatal period. All interventions included some form of abdominal exercise. Other interventions included abdominal binding, kinesiotape and electrical stimulation. There was moderate certainty evidence from six trials (n = 161) that abdominal exercise led to a small reduction in inter-recti distance (MD -0.43 cm, 95% CI -0.82 to -0.05) in postnatal women compared to usual care.

LIMITATIONS

Three of the 16 trials had a low risk of bias.

CONCLUSION AND IMPLICATIONS

Conservative interventions do not lead to clinically significant reductions in inter-recti distance in women postnatally but abdominal exercises may have other physical and psychosocial benefits in the management of DRAM. Systematic Review Registration Number PROSPERO (CRD42020172529).

A possible physiological mechanism of rectocele formation in women

BACKGROUND

We aimed to determine the anorectal physiological factors associated with rectocele formation.

METHODS

Female patients (N = 32) with severe constipation, fecal incontinence, or suspicion of rectocele, who had undergone magnetic resonance defecography and anorectal function tests between 2015 and 2021, were retrospectively included for analysis. The anorectal function tests were used to measure pressure in the anorectum during defecation. Rectocele characteristics and pelvic floor anatomy were determined with magnetic resonance defecography. Constipation severity was determined with the Agachan score. Information regarding constipation-related symptoms was collected.

RESULTS

Mean rectocele size during defecation was 2.14 ± 0.88 cm. During defecation, the mean anal sphincter pressure just before defecation was 123.70 ± 67.37 mm Hg and was associated with rectocele size (P = 0.041). The Agachan constipation score was moderately correlated with anal sphincter pressure just before defecation (r = 0.465, P = 0.022), but not with rectocele size (r = 0.276, P = 0.191). During defecation, increased anal sphincter pressure just before defecation correlated moderately and positively with straining maneuvers (r = 0.539, P = 0.007) and defecation blockage (r = 0.532, P = 0.007). Rectocele size correlated moderately and positively with the distance between the pubococcygeal line and perineum (r = 0.446, P = 0.011).

CONCLUSION

Increased anal sphincter pressure just before defecation is correlated with the rectocele size. Based on these results, it seems important to first treat the increased anal canal pressure before considering surgical rectocele repair to enhance patient outcomes.

Tissue Engineering Neovagina for Vaginoplasty in Mayer-Rokitansky-Küster-Hauser Syndrome and Gender Dysphoria Patients: A Systematic Review

Background: Vaginoplasty is a surgical solution to multiple disorders, including Mayer-Rokitansky-Küster-Hauser syndrome and male-to-female gender dysphoria. Using nonvaginal tissues for these reconstructions is associated with many complications, and autologous vaginal tissue may not be sufficient. The potential of tissue engineering for vaginoplasty was studied through a systematic bibliography search. Cell types, biomaterials, and signaling factors were analyzed by investigating advantages, disadvantages, complications, and research quantity. Search Methods: A systematic search was performed in Medline, EMBASE, Web of Science, and Scopus until March 8, 2022. Term combinations for tissue engineering, guided tissue regeneration, regenerative medicine, and tissue scaffold were applied, together with vaginoplasty and neovagina. The snowball method was performed on references and a Google Scholar search on the first 200 hits. Original research articles on human and/or animal subjects that met the inclusion (reconstruction of vaginal tissue and tissue engineering method) and no exclusion criteria (not available as full text; written in foreign language; nonoriginal study article; genital surgery other than neovaginal reconstruction; and vaginal reconstruction with autologous or allogenic tissue without tissue engineering or scaffold) were assessed. The Strengthening the Reporting of Observational Studies in Epidemiology (STROBE) checklist, the Newcastle-Ottawa Scale, and the Gold Standard Publication Checklist were used to evaluate article quality and bias. Outcomes: A total of 31 out of 1569 articles were included. Data extraction was based on cell origin and type, biomaterial nature and composition, host species, number of hosts and controls, neovaginal size, replacement fraction, and signaling factors. An overview of used tissue engineering methods for neovaginal formation was created, showing high variance of cell types, biomaterials, and signaling factors and the same topics were rarely covered multiple times. Autologous vaginal cells and extracellular matrix-based biomaterials showed preferential properties, and stem cells carry potential. However, quality confirmation of orthotopic cell-seeded acellular vaginal matrix by clinical trials is needed as well as exploration of signaling factors for vaginoplasty. Impact statement General article quality was weak to sufficient due to unreported cofounders and incomplete animal study descriptions. Article quality and heterogenicity made identification of optimal cell types, biomaterials, or signaling factors unreliable. However, trends showed that autologous cells prevent complications and compatibility issues such as healthy cell destruction, whereas stem cells prevent cross talk (interference of signaling pathways by signals from other cell types) and rejection (but need confirmation testing beyond animal trials). Natural (orthotopic) extracellular matrix biomaterials have great preferential properties that encourage future research, and signaling factors for vascularization are important for tissue engineering of full-sized neovagina.

Absorbable Electrospun Poly-4-hydroxybutyrate Scaffolds as a Potential Solution for Pelvic Organ Prolapse Surgery

Women with pelvic organ prolapse (POP) have bothersome complaints that significantly affect their quality of life. While native tissue repair is associated with high recurrence rates, polypropylene knitted implants have caused specific implant-related adverse events that have detrimental, often irreversible, effects. We hypothesize that surgical outcome can be improved with a tissue-engineered solution using an absorbable implant that mimics the natural extracellular matrix (ECM) structure, releases estrogen, and activates collagen metabolism by fibroblasts as the main regulators of wound healing. To this aim, we produced electrospun poly-4-hydroxybutyrate (P4HB) scaffolds and biofunctionalized them with estradiol (E2). The cell-implant interactions relevant for POP repair were assessed by seeding primary POP vaginal fibroblasts isolated from patients on electrospun P4HB scaffolds with 1%, 2%, or 5% E2 and without E2. To test our hypothesis on whether ECM mimicking structures should improve regeneration, electrospun P4HB was compared to knitted P4HB implants. We evaluated vaginal fibroblast proliferation, ECM deposition, and metabolism by quantification of collagen, elastin, and matrix metalloproteinases and by gene expression analysis for 28 days. We established effective E2 drug loading with a steady release over time. Significantly higher cell proliferation, collagen-, and elastin deposition were observed on electrospun P4HB scaffolds as compared to knitted P4HB. For this study, physical properties of the scaffolds were more determinant on the cell response than the release of E2. These results indicate that making these electrospun P4HB scaffolds E2-releasing appears to be technically feasible. In addition, electrospun P4HB scaffolds promote the cellular response of vaginal fibroblasts and further studies are merited to assess if their use results in improved surgical outcomes in case of POP repair.

Distinctive structure, composition and biomechanics of collagen fibrils in vaginal wall connective tissues associated with pelvic organ prolapse

Collagen is the predominant structural protein within connective tissues. Pelvic organ prolapse (POP) is characterized by weakening of the pelvic floor connective tissues and loss of support for pelvic organs. In this study, we examined the multiscale structure, molecular composition and biomechanics of native collagen fibrils in connective tissues of the posterior vaginal fornix collected from healthy women and POP patients, and established the correlation of these properties with clinical POP quantification (POP-Q) scores. The collagen characteristics, including collagen amount, ratio of Collagen I and Collagen III, collagen fibril d-period, alignment and stiffness, were found to change progressively with the increase of the clinical measurement of Point C, a measure of uterine descent and apical prolapse. The results imply that a severe prolapse is associated with stiffer collagen fibrils, reduced collagen d-period, increased fibril alignment and imbalanced collagen synthesis, degradation and deposition. Additionally, prolapse progression appears to be synchronized with deterioration of the collagen matrix, suggesting that a POP-Q score obtained via a non-invasive clinical test can be potentially used to quantitatively assess collagen abnormality of a patient's local tissue. STATEMENT OF SIGNIFICANCE: Abnormal collagen metabolism and deposition are known to associate with connective tissue disorders, such as pelvic organ prolapse. Quantitative correlation of the biochemical and biophysical characteristics of collagen in a prolapse patient's tissue with the clinical diagnostic measurements is unexplored and unestablished. This study fills the knowledge gap between clinical prolapse quantification and the individual's cellular and molecular disorders leading to connective tissue failure, thus, provides the basis for clinicians to employ personalized treatment that can best manage the patient's condition and to alert pre-symptomatic patients for early management to avoid unwanted surgery.

Expression of CD44, Transforming Growth Factor-β, and Matrix Metalloproteinases in Women With Pelvic Organ Prolapse

Background

Defects in the pelvic floor connective tissue may underlie the etiology of pelvic organ prolapse (POP). We hypothesized that the expression of proteins regulating extracellular matrix turnover is altered in the uterosacral ligament of women with POP. We compared the expression of CD44, transforming growth factor (TGF)-β, and matrix metalloproteinases (MMPs) 2/9 in women with and without POP.

Methods and Results

This matched case-control study included 30 postmenopausal women, with POP stage 2 and higher according to the POP quantification system, and 30 postmenopausal women without POP. Immunohistochemical analyses of the uterosacral ligament specimens obtained after hysterectomy were performed to determine CD44, TGF-β, MMP-2, and MMP-9 expression. The expression was quantified using ImageJ software, and the association between prolapse occurrence and risk factors was evaluated using Spearman's correlation analysis. CD44 expressions were significantly lower (p < 0.05), whereas MMP-2 and MMP-9 expression was higher (p < 0.0001 and p < 0.05, respectively), in the POP group than in the control group. The expression of TGF-β was similar in both groups. The occurrence of uterine prolapse was positively correlated with age, postmenopausal age, and MMP-2 and MMP-9 expression (p < 0.01) and negatively correlated with CD44 expression (p < 0.05).

Conclusion

CD44, MMP-2, and MMP-9 may play critical roles in the pathogenesis of POP and may be candidate biomarkers of POP progression.

Advancing our understanding of genetic risk factors and potential personalized strategies for pelvic organ prolapse

Pelvic organ prolapse is a common gynecological condition with limited understanding of its genetic background. In this work, we perform a genome-wide association meta-analysis comprising 28,086 cases and 546,291 controls from European ancestry. We identify 19 novel genome-wide significant loci, highlighting connective tissue, urogenital and cardiometabolic as likely affected systems. Here, we prioritize many genes of potential interest and assess shared genetic and phenotypic links. Additionally, we present the first polygenic risk score, which shows similar predictive ability (Harrell C-statistic (C-stat) 0.583, standard deviation (sd) = 0.007) as five established clinical risk factors combined (number of children, body mass index, ever smoked, constipation and asthma) (C-stat = 0.588, sd = 0.007) and demonstrates a substantial incremental value in combination with these (C-stat = 0.630, sd = 0.007). These findings improve our understanding of genetic factors underlying pelvic organ prolapse and provide a solid start evaluating polygenic risk scores as a potential tool to enhance individual risk prediction.

Although pelvic organ prolapse is a common gynecological condition, the genetic component of disease risk is not well known. Here the authors find common genetic variants associated with the disease and present a polygenic risk score to enhance individual risk prediction.

Biaxial Murine Vaginal Remodeling With Reproductive Aging

Higher reproductive age is associated with an increased risk of gestational diabetes, pre-eclampsia, and severe vaginal tearing during delivery. Further, menopause is associated with vaginal stiffening. However, the mechanical properties of the vagina during reproductive aging before the onset of menopause are unknown. Therefore, the first objective of this study was to quantify the biaxial mechanical properties of the nulliparous murine vagina with reproductive aging. Menopause is further associated with a decrease in elastic fiber content, which may contribute to vaginal stiffening. Hence, our second objective was to determine the effect of elastic fiber disruption on the biaxial vaginal mechanical properties. To accomplish this, vaginal samples from CD-1 mice aged 2-14 months underwent extension-inflation testing protocols (n = 64 total; n = 16/age group). Then, half of the samples were randomly allocated to undergo elastic fiber fragmentation via elastase digestion (n = 32 total; 8/age group) to evaluate the role of elastic fibers. The material stiffness increased with reproductive age in both the circumferential and axial directions within the control and elastase-treated vaginas. The vagina demonstrated anisotropic mechanical behavior, and anisotropy increased with age. In summary, vaginal remodeling with reproductive age included increased direction-dependent material stiffness, which further increased following elastic fiber disruption. Further work is needed to quantify vaginal remodeling during pregnancy and postpartum with reproductive aging to better understand how age-related vaginal remodeling may contribute to an increased risk of vaginal tearing.

The difference in collagen type-1 expression in women with and without pelvic organ prolapse: a systematic review and meta-analysis

INTRODUCTION AND HYPOTHESIS

This study was aimed at identifying the difference in collagen type-1 expression in women with and without pelvic organ prolapse (POP).

METHODS

A systematic review and meta-analysis was carried out women with and without pelvic organ prolapse. This meta-analysis was conducted on research articles describing the evaluation of collagen type-1 expression between patients with and without POP. The articles were obtained from PubMed, EBSCO, and ProQuest, and were published between January 2000 and June 2021. Pooled mean difference (MD) and pooled odds ratio (OR) were calculated using fixed effect models. Review Manager (RevMan 5.4) was used to analyze the data. The main outcome measures were pooled MD and pooled OR of collagen type-1 expression in patients with and without POP.

RESULTS

A total of seven case-control studies were included in the meta-analysis using the effect size of the MD and two case-control studies were included in the meta-analysis using the effect size of the OR. A total of 247 POP cases and 132 non-POP cases were identified from the studies. Our study indicated that patients with POP had a lower level of collagen type-1 expression than non-POP patients (MD = -6.77; 95% CI: -8.37, -5.17, p < 0.00001). Patients with low expression of collagen type-1 in pelvic support tissue are at a more than 3 times higher risk of suffering from pelvic organ prolapse (OR = 3.23, 95% CI: 1.52 to 6.87, p = 0.002).

CONCLUSION

The results of this study showed that patients with pelvic organ prolapse have lower expression of collagen type-1 than nonpelvic organ prolapse patients.

The rs2165241 polymorphism of the Loxl1 gene in postmenopausal women with pelvic organ prolapse

OBJECTIVE

This study aimed to verify the presence of polymorphism rs2165241 of the lysyl oxidase-like 1 (Loxl1) gene and its association with pelvic organ prolapse (POP) in Brazilian women and determine risk factors for POP development.

METHODS

The study was previously approved by the local research and ethics board. Postmenopausal women were included and divided into POP (stages III and IV) and control (stages 0 and I) groups. Peripheral blood samples were collected, and the DNA sequence of interest was analyzed by real-time reverse-transcriptase polymerase chain reaction. We used logistic regression and considered a recessive model of inheritance for the analysis, with p < 0.05 for significance.

RESULTS

A total of 836 women were assessed: 426 POP cases and 410 controls. The frequencies of CC, CT and TT genotypes were similar in both groups. Age (odds ratio [OR] = 1.1, 95% confidence interval [CI] = 1.07; 1.14), number of vaginal births (OR = 17.06, 95% CI = 5.94; 48.97), family history (OR = 2.87, 95% CI = 1.57; 5.22) and weight of largest newborn (OR = 1.001, 95% CI = 1.0003; 1.001) were independent risk factors for POP, while multiple cesarean sections (two or more) was protective (OR = 0.17, 95% CI = 0.07; 0.42).

CONCLUSION

No association was detected between rs2165241 of the Loxl1 gene and POP.

Identification and In Silico Characterization of a Novel COLGALT2 Gene Variant in a Child with Mucosal Rectal Prolapse

Rectal prolapse is influenced by many factors including connective tissue dysfunction. Currently, there is no data about genetic contribution in the etiology of this disorder. In this study, we performed trio whole-exome sequencing in an 11-year-old girl with mucosal rectal prolapse and her parents and sibling. Genetic testing revealed a novel heterozygous missense variant c.1406G>T; p.G469V in exon 11 of the COLGALT2 gene encoding the GLT25 D2 enzyme. Sanger sequencing confirmed this variant only in the patient while the mother, father and sister showed a wild-type sequence. The pathogenicity of the novel variant was predicted using 10 different in silico tools that classified it as pathogenic. Further, in silico prediction, according to Phyre2, Project HOPE, I-Mutant3.0 and MutPred2 showed that the missense variant can decrease protein stability and cause alterations in the physical properties of amino acids resulting in structural and functional changes of the GLT25D2 protein. In conclusion, the present study identifies a previously unknown missense mutation in the COLGALT2 gene that encodes the enzyme involved in collagen glycosylation. The clinical features observed in the patient and the results of in silico analysis suggest that the new genetic variant can be pathogenic.

Protease activities of vaginal Porphyromonas species disrupt coagulation and extracellular matrix in the cervicovaginal niche

Porphyromonas asaccharolytica and Porphyromonas uenonis are common inhabitants of the vaginal microbiome, but their presence has been linked to adverse health outcomes for women, including bacterial vaginosis and preterm birth. However, little is known about the pathogenesis mechanisms of these bacteria. The related oral opportunistic pathogen, Porphyromonas gingivalis, is comparatively well-studied and known to secrete numerous extracellular matrix-targeting proteases. Among these are the gingipain family of cysteine proteases that drive periodontal disease progression and hematogenic transmission to the placenta. In this study, we demonstrate that vaginal Porphyromonas species secrete broad-acting proteases capable of freely diffusing within the cervicovaginal niche. These proteases degrade collagens that are enriched within the cervix (type I) and chorioamniotic membranes (type IV), as well as fibrinogen, which inhibits clot formation. Bioinformatic queries confirmed the absence of gingipain orthologs and identified five serine, cysteine, and metalloprotease candidates in each species. Inhibition assays revealed that each species' proteolytic activity can be partially attributed to a secreted metalloprotease with broad substrate specificity that is distantly related to the P. gingivalis endopeptidase PepO. This characterization of virulence activities in vaginal Porphyromonas species highlights their potential to alter the homeostasis of reproductive tissues and harm human pregnancy through clotting disruption, fetal membrane weakening, and premature cervical remodeling.

Application of estrogen for the treatment of stress urinary incontinence in mice

BACKGROUND

Stress urinary incontinence (SUI) is a pervasive health tissue among women, which seriously affects the quality of life. The etiology of SUI is complex and diverse in women, with past studies having demonstrated that estrogen deficiency plays an important role in pelvic floor muscle atrophy and urethral degeneration. We comprehensively investigated the effects of estrogen in the treatment of SUI in female mice at cellular and animal levels.

METHODS

L929 fibroblasts mechanical injury model was established by four-point bending device, and SUI mouse model was established by vaginal dilation method commonly used to simulate labor injury. After estrogen treatment, the expressions of Collagen I, Collagen III, Elastin, TIMP-1, TIMP-2, MMP-2, and MMP-9 were detected, the leak point pressure (LPP) and abdominal leak point pressure (ALPP) of mice in each group were detected, and both the effect of estrogen on extracellular matrix remodeling of mouse urethra and anterior vaginal wall was observed from the histological level.

RESULTS

The results revealed that an appropriate amount of estrogen can promote the expression of Collagen I, Collagen III, Elastin, TIMP-1, and TIMP-2, decrease the expression of MMP-2 and MMP-9, and maintain the dynamic balance of MMPs/TIMPs at both cellular and animal levels. Meanwhile, we determined that estrogen can increase the LPP and ALPP values of SUI mice. The collagen fibers' content in the mice treated with estrogen was significantly greater than in the control group mice.

CONCLUSIONS

The estrogen may alleviate the symptoms of SUI by reconstituting ECM, thus laying a solid foundation for further exploration of estrogen therapy.

Mouse Knockout Models for Pelvic Organ Prolapse: a Systematic Review

INTRODUCTION AND HYPOTHESIS

Mouse knockout (KO) models of pelvic organ prolapse (POP) have contributed mechanistic evidence for the role of connective tissue defects, specifically impaired elastic matrix remodeling. Our objective was to summarize what mouse KO models for POP are available and what have we learned from these mouse models about the pathophysiological mechanisms of POP development.

METHODS

We conducted a systematic review and reported narrative findings according to PRISMA guidelines. Two independent reviewers searched PubMed, Scopus and Embase for relevant manuscripts and conference abstracts for the time frame of January 1, 2000, to March 31, 2021. Conference abstracts were limited to the past 5 years.

RESULTS

The search strategy resulted in 294 total titles. We ultimately included 25 articles and an additional 11 conference abstracts. Five KO models have been studied: Loxl1, Fbln5, Fbln3, Hoxa11 and Upii-sv40t. Loxl1 and Fbln5 KO models have provided the most reliable and predictable POP phenotype. Loxl1 KO mice develop POP primarily from failure to heal after giving birth, whereas Fbln5 KO mice develop POP with aging. These mouse KO models have been used for a wide variety of investigations including genetic pathways involved in development of POP, biomechanical properties of the pelvic floor, elastic fiber deposition, POP therapies and the pathophysiology associated with mesh complications.

CONCLUSIONS

Mouse KO models have proved to be a valuable tool in the study of specific genes and their role in the development and progression of POP. They may be useful to study POP treatments and POP complications.

Role of Fibroblasts and Myofibroblasts on the Pathogenesis and Treatment of Pelvic Organ Prolapse

Pelvic organ prolapse (POP) is a multifactorial connective tissue disorder caused by damage to the supportive structures of the pelvic floor, leading to the descent of pelvic organs in the vagina. In women with POP, fibroblast function is disturbed or altered, which causes impaired collagen metabolism that affects the mechanical properties of the tissue. Ideal surgical repair, either native tissue repair or POP surgery using an implant, aims to create a functional pelvic floor that is load-bearing, activating fibroblasts to regulate collagen metabolism without creating fibrotic tissue. Fibroblast function plays a crucial role in the pathophysiology of POP by directly affecting the connective tissue quality. On the other hand, fibroblasts determine the success of the POP treatment, as the fibroblast-to-(myo)fibroblast transition is the key event during wound healing and tissue repair. In this review, we aim to resolve the question of “cause and result” for the fibroblasts in the development and treatment of POP. This review may contribute to preventing the development and progress of anatomical abnormalities involved in POP and to optimizing surgical outcomes.

Design, mechanical and degradation requirements of biodegradable metal mesh for pelvic floor reconstruction

Pelvic organ prolapse (POP) is the herniation of surrounding tissue and organs into the vagina and or rectum, and is a result of weakening of pelvic floor muscles, connective tissue,...

Role of fibulin-5 insufficiency and prolapse progression on murine vaginal biomechanical function

The vagina plays a critical role in supporting the pelvic organs and loss of support leads to pelvic organ prolapse. It is unknown what microstructural changes influence prolapse progression nor how decreased elastic fibers contributes to vaginal remodeling and smooth muscle contractility. The objective for this study was to evaluate the effect of fibulin-5 haploinsufficiency, and deficiency with progressive prolapse on the biaxial contractile and biomechanical function of the murine vagina. Vaginas from wildtype (n = 13), haploinsufficient (n = 13), and deficient mice with grade 1 (n = 9) and grade 2 or 3 (n = 9) prolapse were explanted for biaxial contractile and biomechanical testing. Multiaxial histology (n = 3/group) evaluated elastic and collagen fiber microstructure. Western blotting quantified protein expression (n = 6/group). A one-way ANOVA or Kruskal-Wallis test evaluated statistical significance. Pearson's or Spearman's test determined correlations with prolapse grade. Axial contractility decreased with fibulin-5 deficiency and POP (p < 0.001), negatively correlated with prolapse grade (ρ = - 0.80; p < 0.001), and positively correlated with muscularis elastin area fraction (ρ = - 0.78; p = 0.004). Circumferential (ρ = 0.71; p < 0.001) and axial (ρ = 0.69; p < 0.001) vaginal wall stresses positively correlated with prolapse grade. These findings demonstrated that fibulin-5 deficiency and prolapse progression decreased vaginal contractility and increased vaginal wall stress. Future work is needed to better understand the processes that contribute to prolapse progression in order to guide diagnostic, preventative, and treatment strategies.

Correlation Between Hypertrophic Cervical Elongation and Pelvic Organ Prolapse

OBJECTIVES

The association between hypertrophic cervical elongation and pelvic organ prolapse (POP) has been observed, but causation has not been determined. This study assessed the relationship of POP with hypertrophic cervical elongation according to menopausal status and the pelvic compartment involved in prolapse.

METHODS

This retrospective single-center case-control study was conducted at Shengjing Hospital of China Medical University between January 2017 and May 2019. Transverse and anteroposterior diameter of the cervix and cervical length were obtained by manual intravaginal measurement for 508 patients with POP and 510 patients without POP. Data were analyzed based on POP compartment and menopausal status.

RESULTS

In the premenopausal group, there was a statistically significant difference in the proportion of patients with hypertrophic cervical elongation in the non-POP and POP groups (P < 0.05); However, among postmenopausal patients, there was no statistical significance between these groups (P > 0.05). Patients with apical compartment POP had a higher proportion of occurrence of hypertrophic cervical elongation than those with nonapical compartment POP (P < 0.05).

CONCLUSIONS

Hypertrophic cervical elongation in premenopausal patients is significantly associated with POP; in particular, there is a significant correlation between apical compartment POP and hypertrophic cervical elongation.

Incarcerated ventral wall hernia after robotic urogynecologic surgery: A case report

Trocar site hernia is a rare complication of minimally invasive surgery, with incidence estimates varying widely. Studies have demonstrated rates of up to 1.2% in patients undergoing gynecologic surgery. Yet, little is known about hernia risk in the urogynecologic patient population who undergo robotic reconstructive surgery. Risk factors for the development of trocar site hernia include both incisional risk factors (trocar placement location, trocar diameter, intraoperative trocar manipulation) and patient risk factors (obesity, pelvic organ prolapse or other hernia). This report presents a case of large incarcerated small bowel hernia at a trocar site following robotic urogynecologic surgery and the resulting interventions, including repeat surgery, to reduce the hernia. This case should prompt urogynecologic surgeons to check port sites after extensive dissections to assess if large peritoneal or fascial defects need additional closure.

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Complex robotic urogynecologic surgery may increase the risk of trocar site hernia.

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Pelvic organ prolapse is an important risk factor to consider for trocar site hernia.

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Surgeons should inspect robotic port sites for extensions after complex dissection.

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Careful closure of peritoneal and/or fascial extensions may be warranted.

Mesenchymal stem cell transplantation for vaginal repair in an ovariectomized rhesus macaque model

BACKGROUND

Current surgical therapies for pelvic organ prolapse (POP) do not repair weak vaginal tissue and just provide support; these therapies may trigger severe complications. Stem cell-based regenerative therapy, due to its ability to reconstruct damaged tissue, may be a promising therapeutic strategy for POP. The objective of this study is to evaluate whether mesenchymal stem cell (MSC) therapy can repair weak vaginal tissue in an ovariectomized rhesus macaque model.

METHODS

A bilateral ovariectomy model was established in rhesus macaques to induce menopause-related vaginal injury. Ten bilaterally ovariectomized rhesus macaques were divided into two groups (n=5/group): the saline group and the MSC group. Three months after ovariectomy, saline or MSCs were injected in situ into the injured vaginal wall. The vaginal tissue was harvested 12 weeks after injection for histological and biochemical analyses to evaluate changes of extracellular matrix, microvascular density, and smooth muscle in the vaginal tissue. Biomechanical properties of the vaginal tissue were assessed by uniaxial tensile testing. Data analysis was performed with unpaired Student's t test or Mann-Whitney.

RESULTS

Twelve weeks after MSC transplantation, histological and biochemical analyses revealed that the content of collagen I, elastin, and microvascular density in the lamina propria of the vagina increased significantly in the MSC group compared with the saline group. And the fraction of smooth muscle in the muscularis of vagina increased significantly in the MSC group. In addition, MSC transplantation improved the biomechanical properties of the vagina by enhancing the elastic modulus.

CONCLUSION

Vaginal MSC transplantation could repair the weak vaginal tissue by promoting extracellular matrix ingrowth, neovascularization, and smooth muscle formation and improve the biomechanical properties of the vagina, providing a new prospective treatment for POP.

Human umbilical cord mesenchymal stem cells reconstruct the vaginal wall of ovariectomized Sprague-Dawley rats: implications for pelvic floor reconstruction

Vaginal structural defects are involved in pelvic organ prolapse (POP). We tested whether mesenchymal stem cell (MSC) therapy can repair the weakened vaginal wall of POP patients as a novel POP treatment. Ninety-six ovariectomized rats were divided into 4 groups (n = 24/group): saline (sal), collagen (col), sal + MSC, and col + MSC groups. Two weeks after ovariectomy, rats received subepithelial injection of 0.3 ml saline, 0.3 ml collagen I gel, and 0.3 ml saline: 3 × 10⁶ human umbilical cord mesenchymal stem cells (HUMSCs), or 0.3 ml collagen I gel: 3 × 10⁶ HUMSCs into the anterior vaginal wall. Eight additional rats underwent in vivo bioluminescence imaging (BLI) to evaluate in vivo cell viability. The BLI signal disappeared within 1 week after MSC injection, and no in vivo MSC differentiation was found. Collagen I content was significantly lower at 4 and 12 weeks in the two MSC groups than in the sal and col groups, while collagen III was significantly higher (P < 0.001). The fraction of smooth muscle in the nonvascular muscularis increased significantly in the two MSC groups at 12 weeks (P < 0.001). ACTA2 mRNA in the col + MSC group was significantly higher than that in the sal group at 2 and 4 weeks (P = 0.042 and P = 0.040). mRNA levels of angiogenic factors (bFGF or VEGF) in the two MSC groups were significantly higher than those in the sal and col groups at different time points. HUMSCs normalized the fibromuscular structures of the vaginal wall of ovariectomized rats potentially through a paracrine effect.

Perioperative outcomes following pelvic floor reconstruction in women with hereditary disorders of connective tissue: a retrospective cohort study

INTRODUCTION AND HYPOTHESIS

Women with hereditary disorders of connective tissue (HDCT) are at increased risk of pelvic organ prolapse (POP) and stress urinary incontinence (SUI). We hypothesized that patients would have increased incidence and severity of perioperative complications up to 6 weeks after surgeries for POP/SUI. Secondary objectives were to compare pre- and post-operative pelvic floor symptoms and anatomical support as well as pelvic floor disorder recurrence.

METHODS

In this multi-center retrospective cohort study, we identified patients with HDCTs by patient history and ICD-9 codes over an 11-year period. Controls without HDCTs were matched 2:1 to the primary POP or SUI procedure and surgeon. Demographic characteristics, perioperative pelvic floor information and complications were collected. A sample size of 65 HDCT patients and 130 controls was calculated to detect a 20% difference in complications with 80% power and alpha of 0.05.

RESULTS

We identified 59 HDCT patients and 118 controls. Of the women with HDCTs, 49% had Ehlers-Danlos, 22% joint hypermobility syndrome, 15% Marfan syndrome, and 14% had others. Compared with controls, HDCT patients had more total perioperative complications (46% vs 22%, p = 0.002); an age-adjusted relative risk of complications was 1.4 (CI 0.7-2.6). HDCT patients had more Clavien-Dindo grades I and II complications (p = 0.02, 0.03) and more hospital readmissions (14% vs 3%, p = 0.01) than controls. There was no difference in the incidence of specific complications nor was there a difference in recurrence of POP (10%) or SUI (11%) between groups.

CONCLUSIONS

Patients with HDCTs had more Clavien-Dindo grade I and II complications following pelvic floor reconstructive surgery and more readmissions.

Quantitative Morphometry of Elastic Fibers in Pelvic Organ Prolapse

Pelvic organ prolapse (POP) is common among older women who have delivered children vaginally. While the pathophysiology is not fully delineated, POP can occur in part from insufficient repair of disrupted elastic matrix fibers. Quantification of structural changes to elastic fibers has not been described previously for POP. The goal of this paper is to present a validated technique for morphometric analysis of elastic fibers in vaginal tissue cultures from lysyl oxidase like-1 knock out (LOXL1 KO) mice with POP. The effect of LOXL1 KO, effect of POP, effect of culture, and effect of elastogenic treatment on the changes in elastin fiber characteristics were tested using vaginal tissues from wild type multiparous (WT), LOXL1 KO multiparous prolapsed (POP) and LOXL1 KO multiparous non-prolapsed (NP) mice. Our results show significantly higher mean aspect ratio, maximum diameter and perimeter length in POP compared to NP after 3 weeks of tissue culture. Further, treatment of POP tissues in culture with growth factors with previously documented elastogenic effects caused a significant increase in the mean area and perimeter length of elastic fibers. This technique thus appears to be useful in quantifying structural changes and can be used to assess the pathophysiology of POP and the effect of elastogenic treatments with potential for POP.

Role of lysyl oxidase like 1 in regulation of postpartum connective tissue metabolism in the mouse vagina†

Pelvic organ prolapse (POP) in lysyl oxidase like-1 knockout (Loxl1 KO) mice occurs primarily in parous mice and is rare in nulliparous mice. We determined the effect of Loxl1 deficiency on postpartum regulation of connective tissue metabolism genes and degradative enzyme activity in the vagina at 20 days gestation or 4 h, 48 h, 7 days, 15 days, 25 days, 7 weeks, or 12 weeks postpartum. Nulliparous Loxl1 KO and wildtype (WT) mice aged 11, 18, or 23 weeks were controls. Gene expression and enzyme activity were assessed using real-time quantitative reverse transcription PCR and fluorescein conjugated gelatin zymography, respectively. Parity, but not aging, had a significant influence on gene expression both with time postpartum and between KO and WT mice. Mmp2, Timp1, Timp2, Timp3, Timp4, Col1a1, Col3a1, Acta2, and Bmp1 were differentially expressed between KO and WT mice. Correlational analysis of gene-gene pairs revealed 10 significant differences between parous KO and WT groups, 5 of which were due to lack of co-expression of Bmp1 in KO mice. The overall enzyme activity that could be attributed to MMPs was significantly higher in WT compared to KO mice both 25 days and 12 weeks postpartum, and MMP activity was significantly lower 15 days and 25 days postpartum compared to KO nulliparous controls, but not WT. These findings suggest that Loxl1 deficiency combined with parity has a significant impact on postpartum regulation of connective tissue metabolism, particularly as it relates to co-expression of Bmp1 and altered proteolytic activity.

Laparoscopic vaginal lateral suspension: technical aspects and initial experience

BACKGROUND

Pelvic organ prolapse (POP) etiology is a combination of anatomical, physiological, genetic, lifestyle, and reproductive factors determine pelvic floor dysfunction. POP is very common across all ages women worldwide and has become an increasing socioeconomic problem with public health consequences, with symptoms that could lead to a significant decrease in quality of life.

METHODS

This study retrospectively analyzes a small case series of our initial experience of laparoscopic vaginal suspension with mesh focusing on the technical aspects of the technique. Although sacrocolpopexy and sacrohysteropexy are the most performed surgical techniques, they are associated with serious complications. Laparoscopic vaginal suspension appears reproducible and safe to learn.

RESULTS

Between November 2017 and January 2020, fifteen patients underwent laparoscopic vaginal suspension for pelvic organ prolapse repair. Despite the small number, for a minimally invasive skilled surgeon, we notice a significative reduction of the learning curve to become proficient in this procedure.

CONCLUSIONS

The diagnosis and management of pelvic organ prolapse are further complicated by what is considered "successful" treatment. Laparoscopic vaginal suspension is a feasible surgical procedure for one-stage treatment of pelvic organ prolapse.

Evaluation of extracellular matrix protein expression and apoptosis in the uterosacral ligaments of patients with or without pelvic organ prolapse

INTRODUCTION AND HYPOTHESIS

This study aimed to compare the expression levels of extracellular matrix (ECM) and apoptosis proteins in the uterosacral ligament (USL) of patients with and without pelvic organ prolapse (POP).

METHODS

The USL were obtained from patients with POP-Q ≥ III (n = 35) and without POP (n = 20). Immunohistochemistry (IHC) staining and RT-qPCR were conducted to assess the protein and mRNA levels, respectively. The levels of type I collagen (COLI), type III collagen (COLIII), matrix metalloproteinase (MMP)1, MMP2, MMP9, tissue inhibitor of metalloproteinase (TIMP)1, TIMP2, estrogen receptor (ER)α, ERβ and apoptosis-related gene B cell lymphoma 2 (Bcl-2)-associated agonist of cell death (Bad) and Bcl-2-associated X (Bax) in the USL were analyzed.

RESULTS

The protein expression and mRNA levels of MMP2 and MMP9, mRNA levels of BAD and BAX, and protein expression of active cleaved-Caspase3 were significantly higher in the POP group. There were no evident differences in COLIII, MMP1 or ERβ expression at either the mRNA or protein level or in TIMP1, TIMP2 or Caspase3 by IHC between the two groups. However, obvious decreases in COLI and ERα were evident at both the mRNA and protein levels in the POP group, and the mRNA levels of TIMP1 and TIMP2 were also decreased compared to those of the control group.

CONCLUSION

ECM in the USL tissues of POP patients is remodeled compared with non-POP patients and is characterized by decreased synthesis and increased degradation of collagen; moreover, the levels of the main proteins involved in apoptosis are increased in POP tissue.

Collagen I and collagen III polymorphisms in women with pelvic organ prolapse

AIMS

Verify the presence of the single nucleotide polymorphisms rs1800012 of the collagen I (COL1A1) and rs1800255 of the collagen III (COL3A1) genes and their association with pelvic organ prolapse (POP) in Brazilian women and to determine risk factors for POP.

METHODS

We assessed 826 postmenopausal women divided into POP (stages III and IV) and control groups (stages 0 and I) by examination and peripheral blood sample collection. DNA sequences of interest were analyzed by real-time reverse-transcriptase polymerase chain reaction. We used logistic regression analyses, recessive and codominance models of inheritance, and P < .05 for significance.

RESULTS

Six-hundred and thirty-four postmenopausal women were included: 348 (54.8%) POP cases and 286 (45.1%) controls. The frequencies of GG, GA, and AA genotypes for COL1A1 were 69.12%, 20.24%, and 10.59% in POP group and 71.79%, 20%, and 8.21% in controls; GG, GT, and TT for COL3A1 were 37.54%, 59.53%, and 2.93% in POP group and 36.24%, 60.14%, and 3.62% in controls. There were no genotypic or allelic association with POP phenotype that link both SNPs rs1800012 and rs1800255 to increased risk of POP. Vaginal delivery (odds ratio [OR] = 13; 95% confidence interval [CI] [4.00-47.08]), POP family history (OR = 3.1; 95% CI [1.49-6.50]), diabetes mellitus (OR = 2.3; 95% CI [1.08-5.21]), number of pregnancies (OR = 1.2; 95% CI [1.05-1.36]), and age (OR = 1.1; 95% CI [1.09-1.19]), were variables of increased risk for POP (P < .05 for all).

CONCLUSION

Our study suggests lack of association between DNA polymorphisms rs1800012 of COL1A1 and rs1800255 of COL3A1 with advanced POP. Vaginal delivery, POP family history, diabetes mellitus, number of pregnancies, and age are risk factors for POP.

Common variants in LAMC1 confer risk for pelvic organ prolapse in Chinese population

BACKGROUND

Pelvic organ prolapse (POP) affects around 15% of postmenopausal women in China. Although it has been widely accepted that genetic variants could confer risk for POP, the genetic susceptibility variants remain largely unknown. Previous studies indicated that LAMC1, which encodes the laminin gamma 1 chain and is critical for extracellular matrix, might be a susceptibility gene for POP. The study is to test the correlation of common variants across the LAMC1 gene with POP susceptibility in Chinese population.

METHODS

A total of 396 individuals, including 161 unrelated patients of POP and 235 healthy controls, were recruited. Ten SNPs, including rs20558, rs20563, rs10911193, rs6424889, rs10911241, rs3768617, rs12073936, rs729819, rs10911214 and rs869133, of LAMC1, were genotyped using standard Sanger sequencing. The UNPHASED program (version 3.1.5) was used to analyze the genotyping data for allelic and genotypic associations.

RESULTS

SNP rs10911241 was significantly associated with POP risk (χ² = 10.70, P = 1.1 E-03). The minor allele (rs10911241-G) carriers exhibited an increased risk of the disease (OR = 1.71, 95% CI = 1.24-2.36).

CONCLUSION

Association of LAMC1 with POP risk in Chinese population strongly supported the involvement of LAMC1 in POP development.

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.

Genome-wide association identifies seven loci for pelvic organ prolapse in Iceland and the UK Biobank

Pelvic organ prolapse (POP) is a downward descent of one or more of the pelvic organs, resulting in a protrusion of the vaginal wall and/or uterus. We performed a genome-wide association study of POP using data from Iceland and the UK Biobank, a total of 15,010 cases with hospital-based diagnosis code and 340,734 female controls, and found eight sequence variants at seven loci associating with POP (P < 5 × 10-8); seven common (minor allele frequency >5%) and one with minor allele frequency of 4.87%. Some of the variants associating with POP also associated with traits of similar pathophysiology. Of these, rs3820282, which may alter the estrogen-based regulation of WNT4, also associates with leiomyoma of uterus, gestational duration and endometriosis. Rs3791675 at EFEMP1, a gene involved in connective tissue homeostasis, also associates with hernias and carpal tunnel syndrome. Our results highlight the role of connective tissue metabolism and estrogen exposure in the etiology of POP.