Treating intrauterine adhesion using conditionally reprogrammed physiological endometrial epithelial cells

Effects and safety of hyaluronic acid gel on intrauterine adhesion and fertility after intrauterine surgery: a systematic review and meta-analysis with trial sequential analysis of randomized controlled trials

OBJECTIVE

This study aimed to determine the efficacy and safety of hyaluronic acid gel for the prevention of intrauterine adhesions and improved fertility after intrauterine surgery.

DATA SOURCES

PubMed, EMBASE, Cochrane Library, Web of science, and ClinicalTrials.gov were searched up to November 1, 2023.

STUDY ELIGIBILITY CRITERIA

Randomized controlled trials that reported intrauterine adhesion and fertility outcomes among women who used hyaluronic acid after intrauterine surgery.

METHODS

The risk of bias was assessed using criteria of the Cochrane Handbook, and the quality of the evidence was evaluated using the Grades of Recommendation, Assessment, Development, and Evaluation system. The Preferred Reporting Items for Systematic Reviews and Meta-Analyses guidelines were followed. A trial sequential analysis was conducted to assess the outcomes, and Stata 14 was used for sensitivity analyses and publication bias analyses.

RESULTS

Data from 16 randomized controlled trials involving 2359 patients were extracted and analyzed. The analysis revealed that hyaluronic acid reduced the incidence of intrauterine adhesion (risk ratio, 0.53; 95% confidence interval, 0.42-0.67; I2=48%) and improve pregnancy rates (risk ratio, 1.24; 95% confidence interval, 1.02-1.50; I2=0%). A subgroup analysis was conducted to evaluate factors that influence the effect of hyaluronic acid on the incidence of intrauterine adhesion. It was found that a small volume of hyaluronic acid reduced the incidence of intrauterine adhesions. Hyaluronic acid exhibited a protective effect among patients who underwent various intrauterine surgeries and who had different gynecologic medical histories. The protective effect was statistically significant after a follow-up of 6 to 12 weeks. The results of the trial sequential analysis indicated that the effect of hyaluronic acid on the incidence of mild intrauterine adhesions, pregnancy rates, live birth rates, and miscarriage rates after intrauterine surgery may be inconclusive and thus further evaluation is required in the form of additional clinical trials. However, the remaining effects were found to be verifiable and did not require more clinical trials for confirmation.

CONCLUSION

Hyaluronic acid can safely and effectively reduce the incidence of intrauterine adhesions and may improve fertility outcomes.

Restoration of functional endometrium in an intrauterine adhesion rat model with endometrial stromal cells transplantation

BACKGROUND

Intrauterine adhesion (IUA) as a prevalent gynecological disease is developed from infection or trauma. However, therapeutic strategies to repair damaged endometrium are relatively limited. Emerging studies have shed light on the crucial role of endometrial stromal cells (EnSCs) in the process of uterine endometrial regeneration. EnSCs isolated from the uterine endometrium have similar characteristics to mesenchymal stem cells (MSCs). However, it is still unknown whether EnSCs could be used as donor cells to treat IUA. The aim of this study was to evaluate the potential efficacy of EnSCs in treating rat IUA.

METHODS

Human EnSCs were isolated from the endometrial tissue of healthy female donors and subjected to extensive expansion and culture in vitro. Immunofluorescence, flow cytometry, cell proliferation assay, trilineage differentiation experiment, and decidualization assay were used to characterize the biological properties of EnSCs. We evaluated the immunoregulatory potential of EnSCs by analyzing their secreted cytokines and conducting bulk RNA sequencing after IFN-γ treatment. After EnSCs were transplanted into the uterine muscle layer in IUA rats, their therapeutic effects and underlying mechanisms were analyzed using histological analysis, Q-PCR, fertility and pregnancy outcome assay, and transcriptome analysis.

RESULTS

We successfully isolated EnSCs from the endometrium of human donors and largely expanded in vitro. EnSCs exhibited characteristics of mesenchymal stem cells and retained responsiveness to sex hormones. Following IFN-γ stimulation, EnSCs upregulated the anti-inflammatory cytokines and activated immunosuppressive molecules. Xenogeneic transplantation of EnSCs successfully repaired injured endometrium and significantly restored the pregnancy rate in IUA rats. Mechanistically, the therapeutic effects of EnSCs on IUA endometrium functioned through anti-inflammation, anti-fibrosis and the secretion of regeneration factor.

CONCLUSIONS

Due to their large expansion ability, immunoregulatory properties, and great potential in treating IUA, EnSCs, as a valuable source of donor cells, could offer a potential treatment avenue for injury-induced IUA.

Activation of cGAS/STING Drives Inflammation and Cellular Senescence of Macrophages in Ovarian Endometrioma Induced by Endometriotic Cyst Fluid

Ovarian endometrioma (OE) is a common gynecological condition characterized by the formation of "chocolate cysts". Recent research indicates that the cyst fluid acts as a "toxic environment" for the ovary and plays a significant role in the development of OE, with macrophages being pivotal. However, the specific molecular and cellular mechanisms of it are not fully understood. In this study, clinical samples are integrated, single-cell sequencing, in vivo and in vitro experimental models to comprehensively investigate the effects of OE fluid on ovarian function and the mechanisms of it. Combined with bioinformatics analysis and experimental validation, the findings demonstrate that OE fluid can cause ovarian function decline, which associated with inflammatory response, and mitochondrial dysfunction and cellular senescence, while activating the cGAS/STING signaling pathway. As a STING inhibitor, H-151 effectively alleviates ovarian dysfunction, inflammatory state and cell apoptosis induced by OE fluid. Furthermore, it is also discovered that H-151 can inhibit OE fluid-induced mitochondrial dysfunction and cellular senescence. These findings provide important theoretical and experimental foundations for further research and development of STING inhibitors as potential drugs for treating ovarian dysfunction.

Intrauterine infusion of platelet-rich plasma improves fibrosis by transforming growth factor beta 1/Smad pathway in a rat intrauterine adhesion model

This study aims to elucidate the effects of Platelet-rich plasma (PRP) in fibrosis development in intrauterine adhesion (IUA), and the associated underlying mechanisms are also explored, which are expected to be a potential therapeutic scheme for IUA. In this research, PRP was obtained and prepared from the peripheral venous blood of rats. A rat model was induced by mechanical injury. Further, PRP was directly injected into the uterus for treatment. The appearance and shape of the uterus were assessed based on the tissues harvested. The fibrosis biomarker levels were analyzed. The transforming growth factor beta 1 (TGF-β1) and Mothers against decapentaplegic homolog 7 (Smad7) levels, the phosphorylation of Smad2 (p-Smad2), and the phosphorylation of Smad3 (p-Smad3) were analyzed, and the molecular mechanism was investigated by rescue experiments. It was found that PRP improved the appearance and shape of the uterus in IUA and increased endometrial thickness and gland numbers. The administration of PRP resulted in a decrease in the expressions of fibrosis markers including collagen I, α-SMA, and fibronectin. Furthermore, PRP increased Smad7 levels and decreased TGF-β1 levels, p-Smad2, and p-Smad3. Meanwhile, administration of TGF-β1 activator reversed the therapeutic effects of PRP in IUA. Collectively, the intrauterine infusion of PRP can promote endometrial damage recovery and improve endometrial fibrosis via the TGF-β1/Smad pathway. Hence, PRP can be a potential therapeutic strategy for IUA.

Long-Term Maintenance of Viable Human Endometrial Epithelial Cells to Analyze Estrogen and Progestin Effects

There are fewer investigations conducted on human primary endometrial epithelial cells (HPEECs) compared to human primary endometrial stromal cells (HPESCs). One of the main reasons is the scarcity of protocols enabling prolonged epithelial cell culture. Even though it is possible to culture HPEECs in 3D over a longer period of time, it is technically demanding. In this study, we successfully established a highly pure, stable, and long-term viable human conditionally reprogrammed endometrial epithelial cell line, designated as eCRC560. These cells stained positive for epithelial markers, estrogen and progesterone receptors, and epithelial cell-cell contacts but negative for stromal and endothelial cell markers. Estradiol (ES) reduced the abundance of ZO-1 in a time- and dose-dependent manner, in contrast to the dose-dependent increase with the progestin dienogest (DNG) when co-cultured with HPESCs. Moreover, ES significantly increased cell viability, cell migration, and invasion of the eCRC560 cells; all these effects were inhibited by pretreatment with DNG. DNG withdrawal led to a significantly disrupted monolayer of eCRC560 cells in co-culture with HPESCs, yet it markedly increased the adhesion of eCRC560 to the human mesothelial MeT-5A cells. The long-term viable eCRC560 cells are suitable for in vitro analysis of HPEECs to study the epithelial compartment of the human endometrium and endometrial pathologies.

Mechanism of Smilax china L. in the treatment of intrauterine adhesions based on network pharmacology, molecular docking and experimental validation

BACKGROUND

Smilax china L. (SCL) is a traditional herbal medicine for the potential treatment of intrauterine adhesion (IUA). However, the mechanisms of action have not yet been determined. In this study, we explored the effects and mechanisms of SCL in IUA by network pharmacology, molecular docking and molecular biology experiments.

METHODS

Active ingredients and targets of SCL were acquired from TCMSP and SwissTargetPrediction. IUA-related targets were collected from the GeneCards, DisGeNET, OMIM and TTD databases. A protein‒protein interaction (PPI) network was constructed by Cytoscape 3.9.1 and analysed with CytoHubba and CytoNCA to identify the core targets. The DAVID tool was used for GO and KEGG enrichment analyses. Furthermore, molecular docking was employed to assess the interaction between the compounds and key targets. Finally, the mechanisms and targets of SCL in IUA were verified by cellular experiments and western blot.

RESULTS

A total of 196 targets of SCL were identified, among which 93 were related to IUA. Topological and KEGG analyses results identified 15 core targets that were involved in multiple pathways, such as inflammation, apoptosis, and PI3K/AKT signalling pathways. Molecular docking results showed that the active compounds had good binding to the core targets. In vitro experiments showed that astilbin (AST), a major component of SCL, significantly reduced TGF-β-induced overexpression of fibronectin (FN), activation of the PI3K/AKT signalling pathway and the expression of downstream factors (NF-κB and BCL2) in human endometrial stromal cells, suggesting that AST ameliorates IUA by mediating the PI3K/AKT/NF-κB and BCL2 proteins.

CONCLUSIONS

AST, a major component of SCL, may be a potential therapeutic agent for IUA. Moreover, its mechanism is strongly associated with regulation of the PI3K/AKT signalling pathway and the downstream NF-κB and BCL2 proteins. This study will provide new strategies that utilize AST for the treatment of IUA.

Exosomes from Human Umbilical Cord Mesenchymal Stem Cells Facilitates Injured Endometrial Restoring in Early Repair Period through miR-202-3p Mediating Formation of ECM

Endometrial damage repair disorder is the main reason of intrauterine adhesions (IUA) and thin endometrium (TA), which is caused by curettage or infection. Exosomal miRNAs derived from human umbilical cord mesenchymal stem cells (hucMSCs) were reported to play an important role in damage repair disorder, including endometrial fibrosis. In this study, we aimed to investigate the role of hucMSCs-derived exosomal microRNA-202-3p (miR-202-3p) in endometrial damage repair. We established rat endometrial injury model according to curettage to mimic women curettage abortion operation. The miRNA array analysis indicated that miR-202-3p was increased and matrix metallopeptidase 11 (MMP11) was decreased in the exosomes-treated rat uterine tissues. Bioinformatics analysis suggested that MMP11 is the target gene of miR-202-3p. We observed that the mRNA and protein of MMP11 were significantly decreased in exosome treatment group on day 3, and the components of extracellular matrix (ECM) COL1A1, COL3A1, COLVI and fibronectin (FN) protein were increased. And we found that when the injured human stromal cells were treated with miR-202-3p overexpression exosomes, the COLVI and FN were also upregulated in protein and mRNA expression level. For the first time MMP11 was proved to be the target gene of miR-202-3p by dual luciferase reporter system. At last, we found the state of stromal cells was better in miR-202-3p overexpression exosomes group compared to exosomes group, and miR-202-3p overexpression exosomes markedly upregulated the FN and collagen on day 3 after endometrial injury. We thought that miR-202-3p overexpression exosomes promoted endometrial repair by regulating ECM remodeling in early repair of damaged endometrium. Taken together, these experimental findings may provide a theoretical basis for understanding endometrial repair and an insight into the clinical treatment for IUA. Human umbilical cord mesenchymal stem cells exosomal miR-202-3p could regulate the expression of MMP11 and promote the accumulation of extracellular matrix, such as COL1A1, COL3A1, COLVI, FN, in the early repair period of endometrial injury.

CRC Therapy Identifies Indian Hedgehog Signaling in Mouse Endometrial Epithelial Cells and Inhibition of Ihh-KLF9 as a Novel Strategy for Treating IUA

Intrauterine adhesion (IUA) causes menstrual disturbance and infertility. There is no effective treatment available for moderate to severe IUA cases. Stem cell-based therapy has been investigated for treating IUA but is limited in clinical applications due to issues including the precise induction of differentiation, tumorigenesis, and unclear molecular mechanisms. In our recent study, we isolated and expanded the long-term cultures of conditional reprogrammed (CR) mouse endometrial epithelial cells. Treating IUA mice with these CR cells (CRCs) restored the morphology and structure of the endometrium and significantly improved the pregnancy rate. In this study, our data with high-throughput sequencing, CRISPR knockout Ihh^-/-CRCs, and transplantation identified for the first time that the Indian hedgehog (Ihh) gene plays a critical role in the regulation of endometrial epithelial cell proliferation. We also found that aberrant activated Ihh-krüppel-like factor 9 (KLF9) signaling contributes to the inhibition of normal progesterone receptor (PR) function in IUA mice. Thus, we hypothesized that inhibition of the Ihh-KLF9 pathway may be a novel strategy to treat IUA. Our data demonstrated that treatment with the hedgehog signaling inhibitor Vismodegib restored the morphology, structure, and microenvironment of the endometrium, and greatly improved the pregnancy rate in IUA mice. This study suggests a promising application of hedgehog inhibitors as a targeted drug in the IUA clinic.

The First Human Vulvar Intraepithelial Neoplasia Cell Line with Naturally Infected Episomal HPV18 Genome

Persistent infection with high-risk HPV leads to cervical cancers and other anogenital cancers and head and neck carcinomas in both men and women. There is no effective drug fortreating HPV infection and HPV-associated carcinomas, largely due to a lack of models of natural HPV infection and the complexity of the HPV life cycle. There are no available cell lines from vulvar, anal, or penile lesions and cancers in the field. In this study, we established the first human cell line from vulvar intraepithelial neoplasia (VIN) with naturally infected HPV18 by conditional reprogramming (CR) method. Our data demonstrated that VIN cells possessed different biological characteristics and diploid karyotypes from HPV18-positive cancer cells (HeLa). Then, we determined that VIN cells contained episomal HPV18 using approaches including the ratio of HPV E2_copy/E7_copy, rolling cycle amplification, and sequencing. The VIN cells expressed squamous epithelium-specific markers that are different from HeLa cells, a cervical adenocarcinoma cell line. When cultured under 3D air-liquid interface (ALI) system, we observed the expression of both early and late differentiation markers involucrin and filaggrin. Most importantly, we were able to detect the expression of viral late gene L1 in the cornified layer of ALI 3D culture derived from VIN cells, suggesting quite different HPV genomic status from cancer cells. We also observed progeny viral particles under transmission electron microscopy (TEM) in ALI 3D cultures, confirming the episomal HPV18 genome and active viral life cycle in the new cell line. To our knowledge, this is the first human VIN cell line with naturally infected HPV18 genome and provides a valuable model for HPV biology studies, HPV-associated cancer initiation and progression, and drug-screening platforms.