Overactivated sonic hedgehog signaling aggravates intrauterine adhesion via inhibiting autophagy in endometrial stromal cells

Prevention of Intrauterine Adhesion with Platelet-Rich Plasma Double-Network Hydrogel

Intrauterine adhesion (IUA) can negatively impact on pregnancy outcomes, leading to reduced pregnancy rates, secondary infertility, and an increased risk of pregnancy complications. Studies have shown that the application of platelet-rich plasma (PRP) in IUA patients is effective. However, the clinical readhesive rate of IUA after treatment is still high, especially in severe cases. Platelet-rich plasma double-network hydrogel (DN gel) is an engineered PRP double network hydrogel, which is a sodium alginate (SA) based PRP hydrogel with egg carton ion cross-linking and fibrin double network. The results of this study show that intrauterine injection of DN gel has a better effect on promoting endometrial regeneration and enhancing endometrial receptivity than PRP gel. The mechanism is analyzed through single-cell sequencing, which may be achieved by increasing the expression of neutrophils (Neut), natural killer cells (NK), and type I classical dendritic cells (cDC1) in the endometrium and inhibiting the infiltration of M2 macrophages. Overall, based on the good healing efficiency and good biocompatibility of DN gel, it is expected to become a method of treating IUA with better efficacy and faster clinical translation.

ULK1 methylation promotes TGF-β1-induced endometrial fibrosis via the FOXP1/DNMT1 axis

Intrauterine adhesion (IUA) is the second most common cause of secondary infertility in women and can also lead to menstrual abnormalities and multiple adverse pregnancy outcomes. Therefore, elucidating the mechanism of its development is crucial for the prevention and treatment of IUA. This study will investigate the function and mechanism of forkhead box P1 (FOXP1)/DNA methyltransferase 1 (DNMT1)/unc-51-like autophagy activating kinase 1 (ULK1) in IUA. Expression levels of key genes were detected using western blot and quantitative - real time reverse transcription polymerase chain reaction. Cell proliferation was detected by CCK-8 and EdU staining. Transcriptional regulation relationships were detected by dual luciferase reporter gene and chromatin immunoprecipitation (ChIP) assay. Methylation station of ULK1 was detected by methylmion specific PCR (MSP). Fibrosis and pathological changes in the uterine cavity tissues were detected by Masson and hematoxylin and eosin staining. It was observed that the expression of FOXP1 and DNMT1 increased in transforming growth factor (TGF)-β1-induced cells, while ULK1 expression decreased. Downregulation of FOXP1 could inhibit human endometrial stromal cells proliferation and autophagy, as well as decrease the expression of fibrogenic factors (collagen type I alpha 1 chain [COL1A1], fibronectin [FN], and alpha-smooth muscle actin [α-SMA]). The results of MSP and ChIP experiments showed that DNMT1 promotes methylation of the ULK1 promoter region and inhibits its transcription. In an animal model, knockdown of FOXP1 alleviated pathological fibrosis and uterine adhesions. Knockdown of FOXP1 can inhibit endometrial fibrosis in IUA rats; FOXP1 could be a potential target for the treatment of IUA.

Intrauterine adhesions assessment by photoacoustic imaging versus high frequency ultrasound imaging in rats

OBJECTIVE

To compare the sensitivity of photoacoustic imaging (PAI) in the detection of Intrauterine adhesions (IUA) at different grades with that of high frequency ultrasound (US), and to investigate whether PAI can evaluate IUA noninvasively and quantitatively by monitoring endometrial oxygenation.

MATERIALS AND METHODS

In vivo high-frequency US/PAI dual-modality imaging was performed in12 rats with IUA and 5 control rats, the monolayer endometrial thickness on US (US-EMT) and the average oxygenation saturation of endometrium on PAI (PA-sO2 Avr) were measured respectively. HE, Masson and immunofluorescence staining were further conducted to investigate the monolayer endometrial thickness (HE-EMT), the number of endometrial glands (HE-EMG), the area ratio of endometrial fibrosis (FAr) and the mean fluorescence intensity of Vascular endothelial growth factor (VEGF) in endometrium (VEGF-MFI). The correlation was analyzed between US-EMT, PA-sO2 Avr and HE-EMT, HE-EMG, FAr, VEGF-MFI. The diagnostic performance of US and PAI for different grades of IUA was compared.

RESULTS

Both US-EMT and PA-sO2 Avr were positively correlated with HE-EMT, HE-EMG, and VEGF-MFI, but negatively correlated with FAr (r = 0.745, 0.608, 0.875, -0.820 and 0.911, 0.756, 0.942, -0.903, respectively). Importantly, the area under the curve (AUC) for detecting stage F1 by PAI was significantly higher than that by US (0.983 vs. 0.625, P = 0.031). No significant difference in the AUC for detecting stage F2 and F3 between PAI and US (0.990 vs 0.987, P = .756; 1.0 vs 1.0, P > .99).

CONCLUSION

PAI can noninvasively and quantitatively evaluate IUA by monitoring endometrial oxygenation, it shows a higher diagnostic performance than US in detecting IUA, especially mild IUA.

Exploring the molecular mechanism of estrogen therapy effectiveness after TCRA in IUA patients at single-cell level

BACKGROUND

Intrauterine adhesion (IUA) is a common cause of clinically refractory infertility, and there exists significant heterogeneity in the treatment outcomes among IUA patients with the similar severity after transcervical resection of adhesion(TCRA). The underlying mechanism of different treatment outcomes occur remains elusive, and the precise contribution of various cell subtypes in this process remains uncertain.

RESULTS

Here, we performed single-cell transcriptome sequencing on 10 human endometrial samples to establish a single-cell atlas differences between patients who responded to estrogen therapy and those who did not. The results showed increased infiltration of immune cells such as monocyte macrophages, T cells, and natural killer (NK) cells in patients who did not respond to estrogen therapy. Our findings indicate that distinct fibroblast subsets are implicated in the modulation of the Wnt, Hippo, and Hedgehog signaling pathways, as evidenced by functional enrichment analyses. This may have implications for the therapeutic efficacy in patients with IUA. Furthermore, we delineated the markers and transcriptional status of different macrophage subsets and identified two cell clusters, CXCL10high and CCL4L2high macrophage subsets, which are intimately associated with inflammation and fibrosis. The state of fibrosis and inflammatory response in human endometrial tissues with disparate treatment outcomes is revealed, and providing evidence to clarify the underlying determinants of sensitivity to estrogen therapy.

CONCLUSIONS

We described the transcriptional status of different cell subtypes in the two groups of patients, providing new ideas for exploring the molecular mechanism of the difference in the effectiveness of estrogen therapy in patients, and providing theoretical basis for providing precise and individualized treatment plans for IUA patients.

Mechanistic insights into intrauterine adhesions

Intrauterine adhesions (IUA), also known as Asherman's syndrome, arise from damage to the basal layer of the endometrium, frequently caused by intrauterine interventions. This damage leads to nonregenerative healing of endometrium resulting in replacement by fibrous connective tissue, which bring about the adherence of opposing endometrium to render the uterine cavity and/or cervical canal partially or completely obliterated. IUA is a common cause of the refractory uterine infertility. Hysteroscopy is the gold standard for diagnosis of IUA. However, the method of accurately predicting the likelihood of achieving a live birth in the future remains established. Classical treatments have shown limited success, particularly in severe cases. Therefore, utilizing new research methods to deepen the understanding of the pathogenesis of IUA will facilitate the new treatment approaches to be found. In this article we briefly described the advances in the pathogenesis of IUA, with focus on inflammation and parenchymal cellular homeostasis disruption, defects in autophagy and the role of ferroptosis, and we also outlined the progress in IUA therapy.

Hedgehog Signaling Pathway in Fibrosis and Targeted Therapies

Hedgehog (Hh) signaling is a well-established developmental pathway; it is crucial for early embryogenesis, cell differentiation, and damage-driven regeneration. It is being increasingly recognized that dysregulated Hh signaling is also involved in fibrotic diseases, which are characterized by excessive extracellular matrix deposition that compromises tissue architecture and function. As in-depth insights into the mechanisms of Hh signaling are obtained, its complex involvement in fibrosis is gradually being illuminated. Notably, some Hh-targeted inhibitors are currently under exploration in preclinical and clinical trials as a means to prevent fibrosis progression. In this review, we provide a concise overview of the biological mechanisms involved in Hh signaling. We summarize the latest advances in our understanding of the roles of Hh signaling in fibrogenesis across the liver, kidneys, airways, and lungs, as well as other tissues and organs, with an emphasis on both the shared features and, more critically, the distinct functional variations observed across these tissues and organs. We thus highlight the context dependence of Hh signaling, as well as discuss the current status and the challenges of Hh-targeted therapies for fibrosis.

Reduced expression of SMAD7 and consequent reduction of autophagy promotes endometrial stromal-myofibroblast transition and fibrosis

Abnormal autophagy and the transforming growth factor-β (TGFβ)-SMAD3/7 signaling pathway play an important role in the development of intrauterine adhesions (IUAs); however, the exact underlying mechanisms remain unclear. In this study, we used IUA patient tissue and SMAD7 conditional knockout mice to detect whether SMAD7 effected IUA via regulation of autophagy and the TGFβ-SMAD3 signaling pathway. We applied a combination of techniques for the detection of p-SMAD3, SMAD7, autophagy and fibrosis-related proteins, autophagic flux, and analysis of the SMAD3 binding site. Endometrial tissue of patients with IUA exhibited lower expression levels of SMAD7. In endometrial stromal cells, silencing of SMAD7 inhibited autophagic flux, whereas overexpressed SMAD7 promoted autophagic flux. This SMAD7-mediated autophagic flux regulates the stromal-myofibroblast transition, and these phenotypes were regulated by the TGFβ-SMAD3 signaling pathway. SMAD3 directly binds to the 3'-untranslated region of transcription factor EB (TFEB) and inhibits its transcription. SMAD7 promoted autophagic flux by inhibiting SMAD3, thereby promoting the expression of TFEB. In SMAD7 conditional knockout mice, the endometria showed a fibrotic phenotype. Simultaneously, autophagic flux was inhibited. On administering the autophagy activator rapamycin, this endometrial fibrosis phenotype was partially reversed. The loss of SMAD7 promotes endometrial fibrosis by inhibiting autophagic flux via the TGFβ-SMAD3 pathway. Therefore, this study reveals a potential therapeutic target for IUA.

Chrysin-loaded PEGylated liposomes protect against alloxan-induced diabetic neuropathy in rats: the interplay between endoplasmic reticulum stress and autophagy

BACKGROUND

Diabetic neuropathy (DN) is recognized as a significant complication arising from diabetes mellitus (DM). Pathogenesis of DN is accelerated by endoplasmic reticulum (ER) stress, which inhibits autophagy and contributes to disease progression. Autophagy is a highly conserved mechanism crucial in mitigating cell death induced by ER stress. Chrysin, a naturally occurring flavonoid, can be found abundantly in honey, propolis, and various plant extracts. Despite possessing advantageous attributes such as being an antioxidant, anti-allergic, anti-inflammatory, anti-fibrotic, and anticancer agent, chrysin exhibits limited bioavailability. The current study aimed to produce a more bioavailable form of chrysin and discover how administering chrysin could alter the neuropathy induced by Alloxan in male rats.

METHODS

Chrysin was formulated using PEGylated liposomes to boost its bioavailability and formulation. Chrysin PEGylated liposomes (Chr-PLs) were characterized for particle size diameter, zeta potential, polydispersity index, transmission electron microscopy, and in vitro drug release. Rats were divided into four groups: control, Alloxan, metformin, and Chr-PLs. In order to determine Chr- PLs' antidiabetic activity and, by extension, its capacity to ameliorate DN, several experiments were carried out. These included measuring acetylcholinesterase, fasting blood glucose, insulin, genes dependent on autophagy or stress in the endoplasmic reticulum, and histopathological analysis.

RESULTS

According to the results, the prepared Chr-PLs exhibited an average particle size of approximately 134 nm. They displayed even distribution of particle sizes. The maximum entrapment efficiency of 90.48 ± 7.75% was achieved. Chr-PLs effectively decreased blood glucose levels by 67.7% and elevated serum acetylcholinesterase levels by 40% compared to diabetic rats. Additionally, Chr-PLs suppressed the expression of ER stress-related genes (ATF-6, CHOP, XBP-1, BiP, JNK, PI3K, Akt, and mTOR by 33%, 39.5%, 32.2%, 44.4%, 40.4%, 39.2%, 39%, and 35.9%, respectively). They also upregulated the miR-301a-5p expression levels by 513% and downregulated miR-301a-5p expression levels by 65%. They also boosted the expression of autophagic markers (AMPK, ULK1, Beclin 1, and LC3-II by 90.3%, 181%, 109%, and 78%, respectively) in the sciatic nerve. The histopathological analysis also showed that Chr-PLs inhibited sciatic nerve degeneration.

CONCLUSION

The findings suggest that Chr-PLs may be helpful in the protection against DN via regulation of ER stress and autophagy.

DKK1 loss promotes endometrial fibrosis via autophagy and exosome-mediated macrophage-to-myofibroblast transition

INTRODUCTION

Intrauterine adhesions (IUA) manifest as endometrial fibrosis, often causing infertility or recurrent miscarriage; however, their pathogenesis remains unclear.

OBJECTIVES

This study assessed the role of Dickkopf WNT signaling pathway inhibitor 1 (DKK1) and autophagy in endometrial fibrosis, using clinical samples as well as in vitro and in vivo experiments.

METHODS

Immunohistochemistry, immunofluorescence and western blot were used to determine the localization and expression of DKK1 in endometrium; DKK1 silencing and DKK1 overexpression were used to detect the biological effects of DKK1 silencing or expression in endometrial cells; DKK1 gene knockout mice were used to observe the phenotypes caused by DKK1 gene knockout.

RESULTS

In patients with IUA, DKK1 and autophagy markers were down-regulated; also, α-SMA and macrophage localization were increased in the endometrium. DKK1 conditional knockout (CKO) mice showed a fibrotic phenotype with decreased autophagy and increased localization of α-SMA and macrophages in the endometrium. In vitro studies showed that DKK1 knockout (KO) suppressed the autophagic flux of endometrial stromal cells. In contrast, ectopic expression of DKK1 showed the opposite phenotype. Mechanistically, we discovered that DKK1 regulates autophagic flux through Wnt/β-catenin and PI3K/AKT/mTOR pathways. Further studies showed that DKK1 KO promoted the secretion of interleukin (IL)-8 in exosomes, thereby promoting macrophage proliferation and metastasis. Also, in DKK1 CKO mice, treatment with autophagy activator rapamycin partially restored the endometrial fibrosis phenotype.

CONCLUSION

Our findings indicated that DKK1 was a potential diagnostic marker or therapeutic target for IUA.

The Endometrial Stem/Progenitor Cells and Their Niches

Endometrial stem/progenitor cells are a type of stem cells with the ability to self-renew and differentiate into multiple cell types. They exist in the endometrium and form niches with their neighbor cells and extracellular matrix. The interaction between endometrial stem/progenitor cells and niches plays an important role in maintaining, repairing, and regenerating the endometrial structure and function. This review will discuss the characteristics and functions of endometrial stem/progenitor cells and their niches, the mechanisms of their interaction, and their roles in endometrial regeneration and diseases. Finally, the prospects for their applications will also be explored.

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.

Incorporation of Decidual Stromal Cells Derived Exosomes in Sodium Alginate Hydrogel as an Innovative Therapeutic Strategy for Advancing Endometrial Regeneration and Reinstating Fertility

Intrauterine adhesion (IUA) stands as a prevalent medical condition characterized by endometrial fibrosis and scar tissue formation within the uterine cavity, resulting in infertility and, in severe cases, recurrent miscarriages. Cell therapy, especially with stem cells, offers an alternative to surgery, but concerns about uncontrolled differentiation and tumorigenicity limit its use. Exosomes, more stable and immunogenicity-reduced than parent cells, have emerged as a promising avenue for IUA treatment. In this study, a novel approach has been proposed wherein exosomes originating from decidual stromal cells (DSCs) are encapsulated within sodium alginate hydrogel (SAH) scaffolds to repair endometrial damage and restore fertility in a mouse IUA model. Current results demonstrate that in situ injection of DSC-derived exosomes (DSC-exos)/SAH into the uterine cavity has the capability to induce uterine angiogenesis, initiate mesenchymal-to-epithelial transformation (MET), facilitate collagen fiber remodeling and dissolution, promote endometrial regeneration, enhance endometrial receptivity, and contribute to the recovery of fertility. RNA sequencing and advanced bioinformatics analysis reveal miRNA enrichment in exosomes, potentially supporting endometrial repair. This finding elucidates how DSC-exos/SAH mechanistically fosters collagen ablation, endometrium regeneration, and fertility recovery, holding the potential to introduce a novel IUA treatment and offering invaluable insights into the realm of regenerative medicine.

Human umbilical cord-derived mesenchymal stem cells and auto-crosslinked hyaluronic acid gel complex for treatment of intrauterine adhesion

OBJECTIVE

The purpose of this study was to explore the therapeutic characteristics of mesenchymal stem cells generated from human umbilical cord (hUC-MSCs) when utilized in conjunction with auto-crosslinked hyaluronic acid gel (HA-gel) for the management of intrauterine adhesion (IUA). The goal was to see how this novel therapy could enhance healing and improve outcomes for IUA patients.

METHODS

In this study, models of intrauterine adhesion (IUA) were established in Sprague-Dawley (SD) rats, which were then organized and divided into hUC-MSCs groups. The groups involved: hUC-MSCs/HA-gel group, control group, and HA-gel group. Following treatment, the researchers examined the uterine cavities and performed detailed analyses of the endometrial tissues to determine the effectiveness of the interventions.

RESULTS

The results indicated that in comparison with to the control group, both HA-gel, hUC-MSCs, and hUC-MSCs/HA-gel groups showed partial repair of IUA. However, in a more notable fashion transplantation of hUC-MSCs/HA-gel complex demonstrated significant dual repair effects. Significant outcomes were observed in the group treated with hUC-MSCs and HA-gel, they showed thicker endometrial layers, less fibrotic tissue, and a higher number of endometrial glands. This treatment strategy also resulted in a significant improvement in fertility restoration, indicating a profound therapeutic effect.

CONCLUSIONS

The findings of this study suggest that both HA-gel, hUC-MSCs, and hUC-MSCs/HA-gel complexes have the potential for partial repair of IUA and fertility restoration caused by endometrium mechanical injury. Nonetheless, the transplantation of the hUC-MSCs/HA-gel complex displayed exceptional dual healing effects, combining effective anti-adhesive properties with endometrial regeneration stimuli.

Glutaminolysis regulates endometrial fibrosis in intrauterine adhesion via modulating mitochondrial function

BACKGROUND

Endometrial fibrosis, a significant characteristic of intrauterine adhesion (IUA), is caused by the excessive differentiation and activation of endometrial stromal cells (ESCs). Glutaminolysis is the metabolic process of glutamine (Gln), which has been implicated in multiple types of organ fibrosis. So far, little is known about whether glutaminolysis plays a role in endometrial fibrosis.

METHODS

The activation model of ESCs was constructed by TGF-β1, followed by RNA-sequencing analysis. Changes in glutaminase1 (GLS1) expression at RNA and protein levels in activated ESCs were verified experimentally. Human IUA samples were collected to verify GLS1 expression in endometrial fibrosis. GLS1 inhibitor and glutamine deprivation were applied to ESCs models to investigate the biological functions and mechanisms of glutaminolysis in ESCs activation. The IUA mice model was established to explore the effect of glutaminolysis inhibition on endometrial fibrosis.

RESULTS

We found that GLS1 expression was significantly increased in activated ESCs models and fibrotic endometrium. Glutaminolysis inhibition by GLS1 inhibitor bis-2-(5-phenylacetamido-1,2,4-thiadiazol-2-yl) ethyl sulfide (BPTES or glutamine deprivation treatment suppressed the expression of two fibrotic markers, α-SMA and collagen I, as well as the mitochondrial function and mTORC1 signaling in ESCs. Furthermore, inhibition of the mTORC1 signaling pathway by rapamycin suppressed ESCs activation. In IUA mice models, BPTES treatment significantly ameliorated endometrial fibrosis and improved pregnancy outcomes.

CONCLUSION

Glutaminolysis and glutaminolysis-associated mTOR signaling play a role in the activation of ESCs and the pathogenesis of endometrial fibrosis through regulating mitochondrial function. Glutaminolysis inhibition suppresses the activation of ESCs, which might be a novel therapeutic strategy for IUA.

Research Models to Mimic Necrotizing Enterocolitis and Inflammatory Bowel Diseases: Focus on Extracellular Vesicles Action

This review focuses on the crucial role of the intestinal epithelium in maintaining intestinal homeostasis and its significance in the pathogenesis of necrotizing enterocolitis (NEC) and inflammatory bowel diseases (IBD). NEC is a devastating neonatal disease, while IBD represents a global healthcare problem with increasing incidence. The breakdown of the intestinal barrier in neonates is considered pivotal in the development and progression of both disorders. This review provides an overview of the current state of in vitro, ex vivo, and animal models to study epithelial injury in NEC and IBD, addressing pertinent questions that engage clinicians and researchers alike. Despite significant advancements in early recognition and aggressive treatment, no single therapy has been conclusively proven effective in reducing the severity of these disorders. Although early interventions have improved clinical outcomes, NEC and IBD continue to impose substantial morbidity, mortality, and economic burdens on affected individuals and society. Consequently, exploring alternative therapeutic options capable of preventing and treating the sequelae of NEC and IBD has become a pressing necessity. In recent decades, extracellular vehicles (EVs) have emerged as a potential solution to modulate the pathogenic mechanism in these multifactorial and complex disorders. Despite the diverse array of proposed models, a comprehensive model to investigate and decelerate the progression of NEC and IBD remains to be established. To bridge the translational gap between preclinical studies and clinical applications, enhancements in the technical development of gut-on-a-chip models and EVs hold considerable promise.

Granulocyte-macrophage colony-stimulating factor promotes endometrial repair after injury by regulating macrophages in mice

Intrauterine adhesion (IUA) caused by endometrial injury is a common cause of female infertility and is challenging to treat. Macrophages play a critical role in tissue repair and cyclical endometrial regeneration. Granulocyte-macrophage colony-stimulating factor (GM-CSF) has significant reparative and anti-fibrotic effects in various tissues. However, there is limited research on the role of GM-CSF in the repair of endometrial injury and the involvement of macrophages in GM-CSF-mediated endometrial repair. In this study, using a mouse model of endometrial scratching injury, we found that GM-CSF treatment accelerated the repair of endometrial injury and improved fertility. At the molecular level, we observed that GM-CSF can downregulate the transcript levels of tumor necrosis factor (TNF) in mouse bone marrow-derived macrophages (BMDMs) stimulated by lipopolysaccharide (LPS) and upregulate the expression of Arginase-1 (Arg-1) and mannose receptor C-type 1 (MRC1). Importantly, during the early and middle stages of injury, GM-CSF increased the proportion of M1-like, M2-like, and M1/M2 mixed macrophages, while in the late stage of injury, GM-CSF facilitated a decline in the number of M2-like macrophages. These findings suggest that GM-CSF may promote endometrial repair by recruiting macrophages and modulating the LPS-induced M1-like macrophages into a less inflammatory phenotype. These insights have the potential to contribute to the development of novel therapeutic approaches for the treatment of intrauterine adhesion and related infertility.

Photothermal therapy of copper incorporated nanomaterials for biomedicine

Studies have reported on the significance of copper incorporated nanomaterials (CINMs) in cancer theranostics and tissue regeneration. Given their unique physicochemical properties and tunable nanostructures, CINMs are used in photothermal therapy (PTT) and photothermal-derived combination therapies. They have the potential to overcome the challenges of unsatisfactory efficacy of conventional therapies in an efficient and non-invasive manner. This review summarizes the recent advances in CINMs-based PTT in biomedicine. First, the classification and structure of CINMs are introduced. CINMs-based PTT combination therapy in tumors and PTT guided by multiple imaging modalities are then reviewed. Various representative designs of CINMs-based PTT in bone, skin and other organs are presented. Furthermore, the biosafety of CINMs is discussed. Finally, this analysis delves into the current challenges that researchers face and offers an optimistic outlook on the prospects of clinical translational research in this field. This review aims at elucidating on the applications of CINMs-based PTT and derived combination therapies in biomedicine to encourage future design and clinical translation.

Mussel-Inspired Calcium Alginate/Polyacrylamide Dual Network Hydrogel: A Physical Barrier to Prevent Postoperative Re-Adhesion

Intrauterine adhesions (IUA) has become one of the main causes of female infertility. How to effectively prevent postoperative re-adhesion has become a clinical challenge. In this study, a mussel-inspired dual-network hydrogel was proposed for the postoperative anti-adhesion of IUA. First, a calcium alginate/polyacrylamide (CA-PAM) hydrogel was prepared via covalent and Ca2+ cross-linking. Benefiting from abundant phenolic hydroxyl groups, polydopamine (PDA) was introduced to further enhance the adhesion ability and biocompatibility. This CA-PAM hydrogel immersed in 10 mg/mL dopamine solution possessed remarkable mechanical strength (elastic modulus > 5 kPa) and super stretchability (with a breaking elongation of 720%). At the same time, it showed excellent adhesion (more than 6 kPa). Surprisingly, the coagulation index of the hydrogel was 27.27 ± 4.91, demonstrating attractive coagulation performance in vitro and the potential for rapid hemostasis after surgery.

Inhibition of Hedgehog signaling ameliorates foam cell formation by promoting autophagy in early atherosclerosis

Macrophages are the origin of most foam cells in the early stage of atherosclerotic plaques. However, the mechanism involved in the formation of macrophage-derived foam cell formation remains unclear. Here, we revealed that the hedgehog (Hh) signaling is critical in autophagy-lysosome pathway regulation and macrophage-derived foam cell formation. Inhibition of Hh signaling by vismodegib ameliorated lipid deposition and oxidative stress level in atherosclerotic plaques in high-fat diet-fed apoE-/- mice. For mechanistic study, how the Hh signaling modulate the process of foam cell formation were accessed afterward. Unexpectedly, we found that suppression of Hh signaling in apoE-/- mice had no significant impact on circulating cholesterol levels, indicating that Hh pathway modulate the procession of atherosclerotic plaque not through a traditional lipid-lowing mechanism. Instead, vismodegib was found to accelerate autophagosomes maturation as well as cholesterol efflux in macrophage-derived foam cell and in turn improve foam cell formation, while autophagy inhibitors (LY294002 or CQ) administration significantly attenuated vismodegib-induced cholesterol efflux and reversed the effect on foam cell formation. Therefore, our result demonstrated that inhibition of the Hh signaling pathway increases cholesterol efflux and ameliorates macrophage-derived foam cell formation by promoting autophagy in vitro. Our data thus suggested a novel therapeutic target of atherosclerosis and indicated the potential of vismodegib to treat atherosclerosis.

Electroacupuncture alleviates intrauterine adhesion through regulating autophagy in rats

Autophagy is a well-conserved metabolic system that maintains homeostasis by relying on lysosomal breakdown. The endometrium of patients with intrauterine adhesion (IUA) and an animal model exhibits impaired autophagy. Autophagy is negatively correlated with inflammation. Activation of autophagy can inhibit the inflammatory response, while defects in autophagy will activate the inflammatory response. Here, we studied whether electroacupuncture (EA) inhibits inflammation and promotes endometrial injury repair by activating endometrial autophagy. The IUA animal model was established by mechanical injury plus lipopolysaccharide infection. EA stimulation was applied to the acupoints Guanyuan (CV4), bilateral Sanyinjiao (SP6), and Zusanli (ST36). The results indicated that EA could improve endometrial morphology, attenuate endometrial fibers, and enhance endometrial receptivity in the rat. EA could increase the autophagosomes of endometrial epithelial cells, increase the levels of LC3 and Beclin1, and decrease the level of p62. Additionally, EA may also suppress the nuclear factor kappa-B (NF-κB) signaling pathway and reduce the release of inflammatory factors. Additionally, the effect of EA was comparable to that of the autophagy agonist rapamycin, and the autophagy inhibitor 3-methyladenine reversed the therapeutic effect of EA. Therefore, we assume that EA may facilitate endometrial healing by activating autophagy and reducing NF-κB signal pathway-mediated inflammation.

MicroRNA-122-5p alleviates endometrial fibrosis via inhibiting the TGF-β/SMAD pathway in Asherman's syndrome

RESEARCH QUESTION

What is the effect of miR-122 on the progression and recovery of fibrosis in Asherman's syndrome?

DESIGN

Endometrial tissue was collected from 21 patients, 11 with intrauterine adhesion (IUA) and 10 without IUA. Quantitative real-time polymerase chain reaction, immunofluorescence and Western blot were applied to observe the expression of mRNAs/miRNAs and protein, respectively. The endometrial physical injury was carried out in C57BL/6 mice to create an endometrial fibrosis model, with intrauterine injection of adenovirus to compare the antifibrosis and repair function of miR-122 on endometrium. The morphology of the uterus was observed using haematoxylin and eosin staining, and fibrosis markers were detected by immunohistochemistry.

RESULTS

miR-122 expression was reduced in patients with IUAs, accompanied by fibrosis. MiR-122 overexpression reduced the degree of fibrosis in endometrial stromal cells. Further molecular analyses demonstrated that miR-122 inhibited fibrosis through the TGF-β/SMAD pathway by directly targeting the 3' untranslated region of SMAD family member 3, suppressing its expression. Notably, miR-122 promoted endometrial regeneration and recovery of pregnancy capacity in a mouse endometrial injury model.

CONCLUSIONS

miR-122 is a critical regulator for repair of endometrial fibrosis and provided new insight for the clinical treatment of intrauterine adhesions.

Treatment strategies for intrauterine adhesion: focus on the exosomes and hydrogels

Intrauterine adhesion (IUA), also referred to as Asherman Syndrome (AS), results from uterine trauma in both pregnant and nonpregnant women. The IUA damages the endometrial bottom layer, causing partial or complete occlusion of the uterine cavity. This leads to irregular menstruation, infertility, or repeated abortions. Transcervical adhesion electroreception (TCRA) is frequently used to treat IUA, which greatly lowers the prevalence of adhesions and increases pregnancy rates. Although surgery aims to disentangle the adhesive tissue, it can exacerbate the development of IUA when the degree of adhesion is severer. Therefore, it is critical to develop innovative therapeutic approaches for the prevention of IUA. Endometrial fibrosis is the essence of IUA, and studies have found that the use of different types of mesenchymal stem cells (MSCs) can reduce the risk of endometrial fibrosis and increase the possibility of pregnancy. Recent research has suggested that exosomes derived from MSCs can overcome the limitations of MSCs, such as immunogenicity and tumorigenicity risks, thereby providing new directions for IUA treatment. Moreover, the hydrogel drug delivery system can significantly ameliorate the recurrence rate of adhesions and the intrauterine pregnancy rate of patients, and its potential mechanism in the treatment of IUA has also been studied. It has been shown that the combination of two or more therapeutic schemes has broader application prospects; therefore, this article reviews the pathophysiology of IUA and current treatment strategies, focusing on exosomes combined with hydrogels in the treatment of IUA. Although the use of exosomes and hydrogels has certain challenges in treating IUA, they still provide new promising directions in this field.

Integrative analysis links autophagy to intrauterine adhesion and establishes autophagy-related circRNA-miRNA-mRNA regulatory network

BACKGROUND

Intrauterine adhesion (IUA) is a troublesome complication characterized with endometrial fibrosis after endometrial trauma. Increasing number of investigations focused on autophagy and non-coding RNA in the pathogenesis of uterine adhesion, but the underlying mechanism needs to be further studied.

METHODS

mRNA expression profile and miRNA expression profile were obtained from Gene Expression Omnibus database. The autophagy related genes were low. Venn diagram was used to set the intersection of autophagy genes and DEGs to obtain ARDEGs. Circbank was used to select hub autophagy-related circRNAs based on ARDEMs. Then, the differentially expressed autophagy-related genes, miRNAs and circRNAs were analyzed by functional enrichment analysis, and protein-protein interaction network analysis. Finally, the expression levels of hub circRNAs and hub miRNAs were validated through RT-PCR of clinical intrauterine adhesion samples. In vitro experiments were investigated to explore the effect of hub ARCs on cell autophagy, myofibroblast transformation and collagen deposition.

RESULTS

11 autophagy-related differentially expressed genes (ARDEGs) and 41 differentially expressed miRNA (ARDEMs) compared between normal tissues and IUA were identified. Subsequently, the autophagy-related miRNA-mRNA network was constructed and hub ARDEMs were selected. Furthermore, the autophagy-related circRNA-miRNA-mRNA network was established. According to the ranking of number of regulated ARDEMs, hsa-circ-0047959, hsa-circ-0032438, hsa-circ-0047301 were regarded as the hub ARCs. In comparison of normal endometrial tissue, all three hub ARCs were upregulated in IUA tissue. All hub ARDEMs were downregulated except has-miR-320c.

CONCLUSIONS

In the current study, we firstly constructed autophagy-related circRNA-miRNA-mRNA regulatory network and identified hub ARCs and ARDEMs had not been reported in IUA.

Dysregulation of Histone Deacetylases Inhibits Trophoblast Growth during Early Placental Development Partially through TFEB-Dependent Autophagy-Lysosomal Pathway

Dysregulated biological behaviors of trophoblast cells can result in recurrent spontaneous abortion (RSA)-whose underlying etiology still remains insufficient. Autophagy, a conserved intracellular physiological process, is precisely monitored throughout whole pregnancy. Although the exact mechanism or role remains elusive, epigenetic modification has emerged as an important process. Herein, we found that a proportion of RSA patients exhibited higher levels of autophagy in villus tissues compared to controls, accompanied with impaired histone deacetylase (HDAC) expression. The purpose of this study is to explore the connection between HDACs and autophagy in the pathological course of RSA. Mechanistically, using human trophoblast cell models, treatment with HDAC inhibitor (HDACI)-trichostatin A (TSA) can induce autophagy by promoting nuclear translocation and transcriptional activity of the central autophagic regulator transcription factor EB (TFEB). Specifically, overactivated autophagy is involved in the TSA-driven growth inhibition of trophoblast, which can be partially reversed by the autophagy inhibitor chloroquine (CQ) or RNA interference of TFEB. In summary, our results reveal that abnormal acetylation and autophagy levels during early gestation may be associated with RSA and suggest the potential novel molecular target TFEB for RSA treatment.

High levels of intracellular endotrophin in adipocytes mediate COPII vesicle supplies to autophagosome to impair autophagic flux and contribute to systemic insulin resistance in obesity

BACKGROUND AND AIMS

Extracellular matrix (ECM) homeostasis plays a crucial role in metabolic plasticity and endocrine function of adipose tissue. High levels of intracellular endotrophin, a cleavage peptide of type VI collagen alpha 3 chain (Col6a3), have been frequently observed in adipocyte in obesity and diabetes. However, how endotrophin intracellularly traffics and influences metabolic homeostasis in adipocyte remains unknown. Therefore, we aimed to investigate the trafficking of endotrophin and its metabolic effects in adipocytes depending on lean or obese condition.

METHODS

We used doxycycline-inducible adipocyte-specific endotrophin overexpressed mice for a gain-of-function study and CRISPR-Cas9 system-based Col6a3-deficient mice for a loss-of-function study. Various molecular and biochemical techniques were employed to examine the effects of endotrophin on metabolic parameters.

RESULTS

In adipocytes during obesity, the majority of endosomal endotrophin escapes lysosomal degradation and is released into the cytosol to mediate direct interactions between SEC13, a major component of coat protein complex II (COPII) vesicles, and autophagy-related 7 (ATG7), leading to the increased formation of autophagosomes. Autophagosome accumulation disrupts the balance of autophagic flux, resulting in adipocyte death, inflammation, and insulin resistance. These adverse metabolic effects were ameliorated by either suppressing ATG7 with siRNA ex vivo or neutralizing endotrophin with monoclonal antibodies in vivo.

CONCLUSIONS

High levels of intracellular endotrophin-mediated autophagic flux impairment in adipocyte contribute to metabolic dysfunction such as apoptosis, inflammation, and insulin resistance in obesity.

Frankincense ameliorates endometriosis via inducing apoptosis and reducing adhesion

Background

Frankincense, a resin derived from trees of the Boswellia genus, has been used as an incense and a type of herbal medicine for treating inflammatory diseases such arthritis, chronic bowel illness, and asthma. While endometriosis is a well-known inflammatory gynecological illness caused by the ectopic attachment and development of uterine tissue over the menstrual cycle, the impact of frankincense on this illness is poorly understood. The purpose of this study was to explore the effects of frankincense on endometriosis.

Methods

We used a network pharmacological assessment, in vitro and in vivo investigations with a human endometriotic cell line as well as a syngeneic uterine transfer mouse model. High-performance liquid chromatographic analysis was used to compare water-extracted frankincense (Fr) to its reference compounds and validate the sample.

Results

A network pharmacological analysis suggested a positive effect of Fr on endometriosis. Fr relieved endometriosis by reducing ectopic endometrial adherence and development, according to both in vivo and in vitro models. We suggested that the ER stress/p53-apoptosis and chemokine-migration/adhesion pathways underlie Fr's anti-endometriotic action using RNA sequencing and bioinformatic analysis.

Conclusion

This study revealed the potential effect of Fr on endometriosis using an experimental investigation. Fr may have the potential to be an effective and safe treatment for endometriosis.

The SFTSV Nonstructural Proteins Induce Autophagy to Promote Viral Replication via Interaction with Vimentin

Severe fever with thrombocytopenia syndrome virus (SFTSV) is a newly identified phlebovirus associated with severe hemorrhagic fever in humans. Studies have shown that SFTSV nucleoprotein (N) induces BECN1-dependent autophagy to promote viral assembly and release. However, the function of other SFTSV proteins in regulating autophagy has not been reported. In this study, we identify SFTSV NSs, a nonstructural protein that forms viroplasm-like structures in the cytoplasm of infected cells as the virus component mediating SFTSV-induced autophagy. We found that SFTSV NSs-induced autophagy was inclusion body independent, and most phenuivirus NSs had autophagy-inducing effects. Unlike N protein-induced autophagy, SFTSV NSs was key in regulating autophagy by interacting with the host's vimentin in an inclusion body-independent manner. NSs interacted with vimentin and induced vimentin degradation through the K48-linked ubiquitin-proteasome pathway. This negatively regulating Beclin1-vimentin complex formed and promoted autophagy. Furthermore, we identified the NSs-binding domain of vimentin and found that overexpression of wild-type vimentin antagonized the induced effect of NSs on autophagy and inhibited viral replication, suggesting that vimentin is a potential antiviral target. The present study shows a novel mechanism through which SFTSV nonstructural protein activates autophagy, which provides new insights into the role of NSs in SFTSV infection and pathogenesis. IMPORTANCE Severe fever with thrombocytopenia syndrome virus (SFTSV) is a newly emerging tick-borne pathogen that causes multifunctional organ failure and even death in humans. As a housekeeping mechanism for cells to maintain steady state, autophagy plays a dual role in viral infection and the host's immune response. However, the relationship between SFTSV infection and autophagy has not been described in detail yet. Here, we demonstrated that SFTSV infection induced complete autophagic flux and facilitated viral proliferation. We also identified a key mechanism underlying NSs-induced autophagy, in which NSs interacted with vimentin to inhibit the formation of the Beclin1-vimentin complex and induced vimentin degradation through K48-linked ubiquitination modification. These findings may help us understand the new functions and mechanisms of NSs and may aid in the identification of new antiviral targets.

HucMSC-EVs Facilitate In Vitro Development of Maternally Aged Preantral Follicles and Oocytes

Follicle developmental capacity and oocyte quality decline with advanced maternal age. Extracellular vesicles from human umbilical cord mesenchymal stem cells (HucMSC-EVs) act as a potential therapeutic product in the treatment of age-related ovarian dysfunction. In vitro culture (IVC) of preantral follicles is a useful method for understanding the mechanism of follicle development and is a promising means for improving female fertility. However, whether HucMSC-EVs have beneficial effects on aged follicle development during IVC has not yet been reported. Our research demonstrated that follicular development with single-addition withdrawal of HucMSC-EVs was better than that with continuous treatment with HucMSC-EVs. HucMSC-EVs facilitated the survival and growth of follicles, promoted the proliferation of granulosa cells (GCs), and improved the steroid hormone secretion of GCs during IVC of aged follicles. Both GCs and oocytes could uptake HucMSC-EVs. Moreover, we observed elevated cellular transcription in GCs and oocytes after treatment with HucMSC-EVs. The RNA sequencing (RNA-seq) results further validated that the differentially expressed genes are related to the promotion of GC proliferation, cell communication, and oocyte spindle organization. Additionally, the aged oocytes displayed a higher maturation rate, presented less aberrant spindle morphology, and expressed a higher level of the antioxidant protein Sirtuin 1 (SIRT1) after treatment with HucMSC-EVs. Our findings suggested that HucMSC-EVs can improve the growth and quality of aged follicles and oocytes in vitro through the regulation of gene transcription, which provides evidence for HucMSC-EVs as potential therapeutic reagents to restore female fertility with advanced age.

Defective autophagy contributes to endometrial epithelial-mesenchymal transition in intrauterine adhesions

Intrauterine adhesions (IUA), characterized by endometrial fibrosis, is a common cause of uterine infertility. We previously demonstrated that partial epithelial-mesenchymal transition (EMT) and the loss of epithelial homeostasis play a vital role in the development of endometrial fibrosis. As a pro-survival strategy in maintaining cell and tissue homeostasis, macroautophagy/autophagy, conversely, may participate in this process. However, the role of autophagy in endometrial fibrosis remains unknown. Here, we demonstrated that autophagy is defective in endometria of IUA patients, which aggravates EMT and endometrial fibrosis, and defective autophagy is related to DIO2 (iodothyronine deiodinase 2) downregulation. In endometrial epithelial cells (EECs), pharmacological inhibition of autophagy by chloroquine (CQ) promoted EEC-EMT, whereas enhanced autophagy by rapamycin extenuated this process. Mechanistically, silencing DIO2 in EECs blocked autophagic flux and promoted EMT via the MAPK/ERK-MTOR pathway. Inversely, overexpression of DIO2 or triiodothyronine (T3) treatment could restore autophagy and partly reverse EEC-EMT. Furthermore, in an IUA-like mouse model, the autophagy in endometrium was defective accompanied by EEC-EMT, and CQ could inhibit autophagy and aggravate endometrial fibrosis, whereas rapamycin or T3 treatment could improve the autophagic levels and blunt endometrial fibrosis. Together, we demonstrated that defective autophagy played an important role in EEC-EMT in IUA via the DIO2-MAPK/ERK-MTOR pathway, which provided a potential target for therapeutic implications.Abbreviations: ACTA2/α-SMA: actin alpha 2, smooth muscle; AMPK: adenosine 5'-monophosphate-activated protein kinase; AKT/protein kinase B: AKT serine/threonine kinase; ATG: autophagy related; CDH1/E-cadherin: cadherin 1; CDH2/N-cadherin: cadherin 2; CQ: chloroquine; CTSD: cathepsin D; DIO2: iodothyronine deiodinase 2; DEGs: differentially expressed genes; EECs: endometrial epithelial cells; EMT: epithelial-mesenchymal transition; FN1: fibronectin 1; IUA: intrauterine adhesions; LAMP1: lysosomal associated membrane protein 1; LPS: lipopolysaccharide; MAP1LC3/LC3: microtubule associated protein 1 light chain 3; MAPK: mitogen-activated protein kinase; MTOR: mechanistic target of rapamycin kinase; Rapa: rapamycin; SQSTM1/p62: sequestosome 1; T3: triiodothyronine; T4: tetraiodothyronine; TFEB: transcription factor EB; PBS: phosphate-buffered saline; TEM: transmission electron microscopy; TGFB/TGFβ: transforming growth factor beta.

Mycobiome Dysbiosis in Women with Intrauterine Adhesions

The vaginal microbiota dysbiosis is closely associated with the development of reproductive diseases. However, the contribution of mycobiome to intrauterine adhesion (IUA) disease remains unknown. Harnessing 16S and ITS2 rDNA sequencing analysis, we investigate both bacterial and fungal microbiota compositions across 174 samples taken from both cervical canal (CC) and middle vagina (MV) sites of IUA patients. Overall, there is no significant difference in microbial diversity between healthy subjects (HS) and IUA patients. However, we observe the IUA-specific bacterial alterations such as increased Dialister and decreased Bifidobacterium and enriched fungal genera like increased Filobasidium and Exophiala. Moreover, site-specific fungal-bacterial correlation networks are discovered in both CC and MV samples of IUA patients. Mechanistic investigation shows that Candida parapsilosis, other than Candida albicans and Candida maltosa, prevents the exacerbation of inflammatory activities and fibrosis, and modulates bacterial microbiota during IUA progression in a rat model of IUA. Our study thus highlights the importance of mycobiota in IUA progression, which may facilitate the development of therapeutic target for IUA prevention. IMPORTANCE Intrauterine adhesion (IUA) often leads to hypomenorrhea, amenorrhea, repeat miscarriages, and infertility. It has been prevalent over the last few decades in up to 13% of women who experience pregnancy termination during the first trimester, and 30% of women undergo dilation and curettage after a late, spontaneous abortion. However, the pathogenesis of IUA remains unclear. Despite reports of microbiota dysbiosis during IUA progression, there is little information on the effect of fungal microbiota on the development of IUA. This study not only enhances our understanding of the mycobiome in IUA patients but also provides potential intervention strategies for prevention of IUA by targeting mycobiome.

Quercetin ameliorates thioacetamide-induced hepatic fibrosis and oxidative stress by antagonizing the Hedgehog signaling pathway

The Hedgehog (Hh) pathway has emerged as a potential target for effectual hepatic repair based on convincing clinical and preclinical evidence that proves its significance in regulating hepatic damage. The purpose of this study is to probe the effect of quercetin on liver fibrosis through the modulation of the Hh pathway. Healthy male Wistar rats were divided into four groups (n = 10). The control group was treated with saline, rats in the remaining three groups received twice a week intoxication with intraperitoneal injections of thioacetamide (200 mg/kg) for the induction of hepatic fibrosis for 6 weeks. After 28 days of quercetin and silymarin treatment, histological changes, serum biochemical index, antioxidant enzyme activity, key mediators of Hh pathway and inflammation were analyzed. Serological analysis showed statistically improved cholesterol, H.D.L-Cholesterol, and L.D.L-Cholesterol in the treatment groups. Superoxide dismutase and glutathione levels were found to be increased after the treatment with quercetin and silymarin. mRNA expression of important mediators of the Hh signaling, and inflammation including Shh, Ihh, Ptch-1, Smo, Hhip, Gli-3, TNF-α, NFκ-β, and Socs-3 were significantly downregulated after the use of quercetin and silymarin. Quercetin also minimized the thioacetamide-induced histopathological changes, as confirmed by a lower degree of hepatic lobule degeneration, the intralobular occurrence of inflammatory cells, and a lower degree of hepatocytic necrosis. Sudan Black B staining showed remarked lipids improvements in the treatment groups. Taken together, these findings demonstrate that quercetin could ameliorate hepatic fibrosis by antagonizing the hedgehog pathway and also suggest the hedgehog pathway as a potential therapeutic target for the treatment of liver fibrosis.

Bioactive NIR-II Light-Responsive Shape Memory Composite Based on Cuprorivaite Nanosheets for Endometrial Regeneration

Intrauterine adhesions (IUAs) caused by mechanical damage or infection increase the risk of infertility in women. Although numerous physical barriers such as balloon or hydrogel are developed for the prevention of IUAs, the therapeutic efficacy is barely satisfactory due to limited endometrial healing, which may lead to recurrence. Herein, a second near-infrared (NIR-II) light-responsive shape memory composite based on the combination of cuprorivaite (CaCuSi₄ O₁₀ ) nanosheets (CUP NSs) as photothermal conversion agents and polymer poly(d,l-lactide-co-trimethylene carbonate) (PT) as shape memory building blocks is developed. The as-prepared CUP/PT composite possesses excellent shape memory performance under NIR-II light, and the improved operational feasibility as an antiadhesion barrier for the treatment of IUAs. Moreover, the released ions (Cu, Si) can stimulate the endometrial regeneration due to the angiogenic bioactivity. This study provides a new strategy to prevent IUA and restore the injured endometrium relied on shape memory composite with enhanced tissues reconstruction ability.

EndMT: New findings on the origin of myofibroblasts in endometrial fibrosis of intrauterine adhesions

BACKGROUND

Intrauterine adhesion (IUA) is one of the leading causes of infertility and the main clinical challenge is the high recurrence rate. The key to solving this dilemma lies in elucidating the mechanisms of endometrial fibrosis. The aim of our team is to study the mechanism underlying intrauterine adhesion fibrosis and the origin of fibroblasts in the repair of endometrial fibrosis.

METHODS

Our experimental study involving an animal model of intrauterine adhesion and detection of fibrosis-related molecules. The levels of molecular factors related to the endothelial-to-mesenchymal transition (EndMT) were examined in a rat model of intrauterine adhesion using immunofluorescence, immunohistochemistry, qPCR and Western blot analyses. Main outcome measures are levels of the endothelial marker CD31 and the mesenchymal markers alpha-smooth muscle actin (α-SMA) and vimentin.

RESULTS

Immunofluorescence co-localization of CD31 and a-SMA showed that 14 days after moulding, double positive cells for CD31 and a-SMA could be clearly observed in the endometrium. Decreased CD31 levels and increased α-SMA and vimentin levels indicate that EndMT is involved in intrauterine adhesion fibrosis.

CONCLUSIONS

Endothelial cells promote the emergence of fibroblasts via the EndMT during the endometrial fibrosis of intrauterine adhesions.

Bone mesenchymal stem cells-derived miR-223-3p-containing exosomes ameliorate lipopolysaccharide-induced acute uterine injury via interacting with endothelial progenitor cells

Bone mesenchymal stem cells (BMSCs) have been used for the treatment of acute uterine injury (AUI)-induced intrauterine adhesion (IUA) via interacting with the endothelial progenitor cells (EPCs), and BMSCs-derived exosomes (BMSCs-exo) may be the key regulators for this process. However, the underlying mechanisms have not been studied. Based on the existed literatures, lipopolysaccharide (LPS) was used to induce AUI in mice models and EPCs to mimic the realistic pathogenesis of IUA in vivo and in vitro. Our data suggested that LPS induced apoptotic and pyroptotic cell death in mice uterine horn tissues and EPCs, and the clinical data supported that increased levels of pro-inflammatory cytokines IL-18 and IL-1β were also observed in IUA patients' serum samples, and silencing of NLRP3 rescued cell viability in LPS-treated EPCs. Next, the LPS-treated EPCs were respectively co-cultured with BMSCs in the Transwell system and BMSCs-exo, and the results hinted that both BMSCs and BMSCs-exo reversed the promoting effects of LPS treatment-induced cell death in EPCs. Then, we screened out miR-223-3p, as the upstream regulator for NLRP3, was enriched in BMSCs-exo, and BMSCs-exo inactivated NLRP3-mediated cell pyroptosis in EPCs via delivering miR-223-3p. Interestingly, upregulation of miR-223-3p attenuated LPS-induced cell death in EPCs. Collectively, we concluded that BMSCs-exo upregulated miR-223-3p to degrade NLRP3 in EPCs, which further reversed the cytotoxic effects of LPS treatment on EPCs to ameliorate LPS-induced AUI.

Application of Bioactive Hydrogels for Functional Treatment of Intrauterine Adhesion

Intrauterine adhesion (IUA) is a common endometrial disease and one of the main causes of infertility in women of childbearing age. Current treatment strategies, such as hysteroscopic adhesion resection, hysteroscopic transcervical resection of adhesion (TCRA), the use of local hormone drugs, and anti-adhesion scaffold implantation, do not provide a satisfactory pregnancy outcome for moderate-severe IUA, which presents a great challenge in reproductive medicine. With the development of material engineering, various bioactive and functional hydrogels have been developed using natural and synthetic biomaterials. These hydrogels are not only used as barely physical barriers but are also designed as vectors of hormone drugs, growth factors, and stem cells. These characteristics give bioactive hydrogels potentially important roles in the prevention and treatment of IUA. However, there is still no systematic review or consensus on the current advances and future research direction in this field. Herein, we review recent advances in bioactive hydrogels as physical anti-adhesion barriers, in situ drug delivery systems, and 3D cell delivery and culture systems for seeded cells in IUA treatment. In addition, current limitations and future perspectives are presented for further research guidance, which may provide a comprehensive understanding of the application of bioactive hydrogels in intrauterine adhesion treatment.

Bioprinting of a Blue Light-Cross-Linked Biodegradable Hydrogel Encapsulating Amniotic Mesenchymal Stem Cells for Intrauterine Adhesion Prevention

Intrauterine adhesion (IUA) is a common and prevailing complication after uterine surgery, which can lead to clinical symptoms such as a low menstrual volume, amenorrhea, periodic lower abdominal pain, infertility, and so on. Placing a three-dimensional printing hydrogel between the injured site and the adjacent tissue is considered to be a physical barrier to prevent adhesion, which can isolate the damaged area during the healing process. In this work, a tissue hydrogel with various proportions of a methacrylated gelatin (GelMA) and methacrylated collagen (ColMA) composite hydrogel loaded with amniotic mesenchymal stem cells (AMSCs) was constructed by using three-dimensional biological printing technology. Compared with the single GelMA hydrogel, the composite antiadhesion hydrogel (GelMA/ColMA) showed an appropriate swelling ratio, enhanced mechanical properties, and impressive stability. Meanwhile, the microstructure of the GelMA/ColMA composite hydrogel showed a denser and interconnected microporous structure. In addition, the cytotoxicity study indicated that the GelMA/ColMA hydrogel has a cytocompatibility nature toward AMSCs. Finally, the fabrication of stem cell encapsulation hydrogels was studied, and the cells could be released continuously for more than 7 days with the normal cell function. The results of in vivo experiments indicated that the GelMA/ColMA/hAMSC (human amnion mesenchymal stem cell) hydrogel can prevent cavity adhesion in a rat IUA model. Therefore, bioprinting a biodegradable hydrogel cross-linked by blue light has satisfactory anticavity adhesion effects with excellent physical properties and biocompatibility, which could be used as a preventive barrier for intrauterine adhesion.

Focus on the Primary Prevention of Intrauterine Adhesions: Current Concept and Vision

Intrauterine adhesion (IUA), and its severe form Asherman syndrome (Asherman’s syndrome), is a mysterious disease, often accompanied with severe clinical problems contributing to a significant impairment of reproductive function, such as menstrual disturbance (amenorrhea), infertility or recurrent pregnancy loss. Among these, its correlated infertility may be one of the most challenging problems. Although there are many etiologies for the development of IUA, uterine instrumentation is the main cause of IUA. Additionally, more complicated intrauterine surgeries can be performed by advanced technology, further increasing the risk of IUA. Strategies attempting to minimize the risk and reducing its severity are urgently needed. The current review will expand the level of our knowledge required to face the troublesome disease of IUA. It is separated into six sections, addressing the introduction of the normal cyclic endometrial repairing process and its abruption causing the formation of IUA; the etiology and prevalence of IUA; the diagnosis of IUA; the classification of IUA; the pathophysiology of IUA; and the primary prevention of IUA, including (1) delicate surgical techniques, such as the use of surgical instruments, energy systems, and pre-hysteroscopic management, (2) barrier methods, such as gels, intrauterine devices, intrauterine balloons, as well as membrane structures containing hyaluronate–carboxymethylcellulose or polyethylene oxide–sodium carboxymethylcellulose as anti-adhesive barrier.

Efficacy of Applying Hyaluronic Acid Gels in the Primary Prevention of Intrauterine Adhesion after Hysteroscopic Myomectomy: A Meta-Analysis of Randomized Controlled Trials

Intrauterine adhesion (IUA), which mainly occurs after intrauterine surgery or an inflammatory process, is an important but often neglected condition in women of reproductive age. The presentation of IUA varies greatly, ranging from symptom-free to severe, with amenorrhea or infertility. With much advanced development of intrauterine instruments, more intrauterine diseases can be successfully cured by hysteroscopic surgery. Among these, submucosal myoma is one of the best examples. Submucosal myomas are often related to abnormal bleeding, anemia, and possible infertility or miscarriage. However, submucosal myoma after hysteroscopic myomectomy may be complicated by IUA in various grades of severity, and its incidence and prevalence might be nearly one-quarter to one-third of patients, suggesting an urgent need for efforts to decrease the risk of developing IUA after hysteroscopic myomectomy. Many strategies have been reported to be useful for this purpose, and intrauterine application of anti-adhesive gels, such as polyethylene oxide–sodium carboxymethylcellulose (PEO-NaCMC) or auto-crosslinked hyaluronic acid (ACHA), has become increasingly popular in routine clinical practice. This meta-analysis is aimed at investigating the effect of ACHA on the primary prevention of IUA formation after hysteroscopic myomectomy. A pooled analysis of three studies (hysteroscopic surgeries for fibroids, polyps, and septum) including 242 women showed that using PEO-NaCMC or ACHA gel decreased the IUA rate with an odds ratio (OR) of 0.364 (95% confidence interval (CI) 0.189–0.703, p = 0.03). Pooled analysis of two studies that limited the use of ACHA in 119 women showed that the application of ACHA gel for the primary prevention of IUA in patients after hysteroscopic myomectomy led to a statistically significant reduction of the development of IUA postoperatively (OR 0.285, 95% CI 0.116–0.701, p = 0.006). All of this suggests that the use of ACHA gel in patients after hysteroscopic myomectomy could significantly reduce de novo IUA, although more evidence is needed.