Bufalin suppresses endometriosis progression by inducing pyroptosis and apoptosis

Research Progress of Caspase in Endometriosis

Endometriosis, a common chronic gynecological disease, refers to the presence and proliferation of endometrial tissue in locations other than the uterine cavity. Approximately 6 to 10% of the population of women of childbearing age are known to have endometriosis; the most common clinical signs are pelvic pain and infertility. Although endometriosis is a benign disease, it exhibits some typical features of malignant tumors, such as proliferation, invasion, metastasis, and recurrence. Endometriosis is considered a chronic, inflammatory, and estrogen-dependent disease, and multiple factors contribute to its occurrence and development. In recent years, increasing attention has been given to the role of apoptosis in the pathogenesis of this disease. Some researchers believe that spontaneous apoptosis of the endometrium is critical in maintaining its normal structure and function, and abnormal apoptosis can promote the occurrence and development of endometriosis. Inflammation is another likely process in the pathogenesis of endometriosis. Inflammation mediates the adhesion, proliferation, differentiation, and invasion of ectopic lesions of endometriosis, primarily by regulating the function of immune cells and increasing the level of proinflammatory cytokines in body fluids. The ultimate initiators of apoptosis and inflammatory cell death (pyroptosis) are the caspase family proteases. In this article, we review the progress in recent years in caspase function as well as the possible role of these enzymes in the pathogenesis of endometriosis, indicating potential treatment strategies.

Regulated Cell Death in Endometriosis

Regulated cell death (RCD) represents a distinct mode of cell demise, differing from accidental cell death (ACD), characterized by specific signaling cascades orchestrated by diverse biomolecules. The regular process of cell death plays a crucial role in upholding internal homeostasis, acting as a safeguard against biological or chemical damage. Nonetheless, specific programmed cell deaths have the potential to activate an immune-inflammatory response, potentially contributing to diseases by enlisting immune cells and releasing pro-inflammatory factors. Endometriosis, a prevalent gynecological ailment, remains incompletely understood despite substantial progress in unraveling associated signaling pathways. Its complexity is intricately tied to the dysregulation of inflammatory immune responses, with various RCD processes such as apoptosis, autophagic cell death, pyroptosis, and ferroptosis implicated in its development. Notably, limited research explores the association between endometriosis and specific RCD pathways like pyroptosis and cuproptosis. The exploration of regulated cell death in the context of endometriosis holds tremendous potential for further advancements. This article thoroughly reviews the molecular mechanisms governed by regulated cell death and their implications for endometriosis. A comprehensive understanding of the regulated cell death mechanism in endometriosis has the potential to catalyze the development of promising therapeutic strategies and chart the course for future research directions in the field.

Hyperandrogenism drives ovarian inflammation and pyroptosis: A possible pathogenesis of PCOS follicular dysplasia

Hyperandrogenemia and persistent chronic inflammation, two main striking features of polycystic ovary syndrome (PCOS), have been proven involved in follicular dysgenesis in PCOS. However, the association between hyperandrogenism and inflammation activation in PCOS is not fully understood. Excess testosterone（T） induces inflammation and pyroptosis activation in a mouse model of PCOS, leading to ovarian dysfunction and fibrosis. Excessive endoplasmic reticulum (ER) stress is present in ovarian granulosa cells (GCs), testosterone-induced PCOS mouse and cellular models. This study found higher levels of interleukin (IL)-1β, IL-8, IL-17, and IL-18 in the follicular fluid of PCOS patients with hyperandrogenemia undergoing IVF treatment. In addition, pyroptosis in GCs was demonstrated, which was significantly elevated in PCOS patients. To clarify the association of hyperandrogenism, inflammation, and pyroptosis activation in PCOS, dehydroepiandrosterone(DHEA)-treated mouse PCOS model and T-treated KGN cell line were explored for PCOS mechanism. Markers of inflammatory activation and pyroptosis were significantly increased after DHEA treatment in mice and T treatment in KGN cells. In addition, ER stress sensor proteins were increased simultaneously. However, suppression of inflammation by genipin(GP) led to decreased pyroptosis in KGN cells but no variation in ER stress sensor proteins. In contrast, when treated with tauroursodeoxycholic acid(TUDCA) to attenuate ER stress, the markers of inflammatory factors were significantly reduced, accompanied by a reduction in pyroptosis. Our results suggest that persistent hyperandrogenemia of PCOS promotes local inflammatory activation of the ovary, and the imbalanced inflammatory microenvironment leads to pyroptosis of GCs, which is mediated by ER stress activation.

Gene expression profiles separate endometriosis lesion subtypes and indicate a sensitivity of endometrioma to estrogen suppressive treatments through elevated ESR2 expression

BACKGROUND

Endometriosis is a common, gynaecological disease characterised by the presence of endometrial-like cells growing outside the uterus. Lesions appear at multiple locations, present with variation in appearance, size and depth of invasion. Despite hormones being the recommended first-line treatment, their efficacy, success and side effects vary widely amongst study populations. Current, hormonal medication for endometriosis is designed to suppress systemic oestrogen. Whether these hormones can influence the lesions themselves is not yet clear. Evidence of hormone receptor expression in endometriotic lesions and their ability to respond is conflicting. A variation in their expression, activation of transcriptional co-regulators and the potential to respond may contribute to their variation in patient outcomes. Identifying patients who would benefit from hormonal treatments remain an important goal in endometriosis research.

METHODS

Using gene expression data from endometriosis lesions including endometrioma (OMA, n = 28), superficial peritoneal lesions (SUP, n = 72) and deeply infiltrating lesions (DIE, n = 78), we performed principal component analysis, differential gene expression and gene correlation analyses to assess the impact of menstrual stage, lesion subtype and hormonal treatment on the gene expression.

RESULTS

The gene expression profiles did not vary based on menstrual stage, but could distinguish lesion subtypes with OMA significantly differentiating from both SUP and DIE. Additionally, the effect of oestrogen suppression medication altered the gene expression profile in OMA, while such effect was not observed in SUP or DIE. Analysis of the target receptors for hormonal medication indicated ESR2 was differentially expressed in OMA and that genes that correlated with ESR2 varied significantly between medicated and non-medicated OMA samples.

CONCLUSIONS

Our results demonstrate of the different lesion types OMA present with strongest response to hormonal treatment directly through ESR2. The data suggests that there may be the potential to target treatment options to individual patients based on pre-surgical diagnoses.

A novel mechanism regulating pyroptosis-induced fibrosis in endometriosis via lnc-MALAT1/miR-141-3p/NLRP3 pathway†

Endometriosis is a chronic inflammatory disease distinguished by ectopic endometrium and fibrosis. NLRP3 inflammasome and pyroptosis are present in endometriosis. Aberrant increase of Long noncoding (Lnc)-metastasis-associated lung adenocarcinoma transcript 1 (MALAT1) plays a vital role in endometriosis. However, the relationship between lnc-MALAT1, pyroptosis, and fibrosis is not completely known. In the present study, we found that the pyroptosis levels in ectopic endometrium of patients with endometriosis were significantly increased, consistent with fibrosis levels. Lipopolysaccharide (LPS) + ATP could induce pyroptosis of primary endometrial stromal cells (ESCs), thereby releasing interleukin (IL)-1β and stimulating transforming growth factor (TGF)-β1-mediated fibrosis. NLRP3 inhibitor MCC950 had the same effect as TGF-β1 inhibitor SB-431542 in suppressing the fibrosis-inducing effect of LPS + ATP in vivo and in vitro. The abnormal increase of lnc-MALAT1 in ectopic endometrium was connected with NLRP3-mediated pyroptosis and fibrosis. Leveraging bioinformatic prediction and luciferase assays combined with western blotting and quantitative reverse transcriptase-polymerase chain reaction, we validated that lnc-MALAT1 sponges miR-141-3p to promote NLRP3 expression. Silencing lnc-MALAT1 in HESCs ameliorated NLRP3-mediated pyroptosis and IL-1β release, thereby relieving TGF-β1-mediated fibrosis. Consequently, our findings suggest that lnc-MALAT1 is critical for NLRP3-induced pyroptosis and fibrosis in endometriosis through sponging miR-141-3p, which may indicate a new therapeutic target of endometriosis treatment.

The prospects of cell therapy for endometriosis

Endometriosis is a chronic inflammatory estrogen-dependent disease characterized by the growth of endometrial-like tissue outside the physiological region. Despite the fact that this disease is common, laparoscopic surgery is currently the gold standard in the treatment of endometriosis. In this regard, it is necessary to develop new effective methods of minimally invasive therapy for endometriosis. One of the promising areas in the treatment of endometriosis is cell therapy. Cellular therapy is a vast branch of therapeutic methods with various agents. Potential cell therapies for endometriosis may be based on the principle of targeting aspects of the pathogenesis of the disease: suppression of estrogen receptor activity, angiogenesis, fibrosis, and a decrease in the content of stem cells in endometriosis foci. In addition, immune cells such as NK cells and macrophages may be promising agents for cell therapy of endometriosis. Standing apart in the methods of cell therapy is the replacement therapy of endometriosis. Thus, many studies in the field of the pathogenesis of endometriosis can shed light not only on the causes of the disease and may contribute to the development of new methods for personalized cell therapy of endometriosis.

Bufalin alleviates acute kidney injury by regulating NLRP3 inflammasome-mediated pyroptosis

BACKGROUND

Recently, there has been an increasing clinical incidence of acute kidney injury (AKI), which rapidly declines renal function and leads to massive tubular cell necrosis. Pyroptosis is an inflammatory process of cell death that is more rapid than apoptosis, which is accompanied by a massive release of inflammasome activation. In the study, we aim to explore whether Bufalin regulates the AKI through the pyroptosis pathway.

METHODS

We have established gentamicin (GM)-induced AKI animal and cell models to simulate the pathological conditions of kidney injury. The expression of renal injury and pyroptosis-related indicators were detected by western blot. PAS staining and IHC staining were used to analyze renal function. CCK-8 assay was performed to detect cell viability after AKI with different treatments. TUNEL staining, flow cytometry and immunofluorescence assays were performed to measure pyroptosis.

RESULTS

After intraperitoneal injection of GM in rats, renal function was significantly decreased, along with a significant increase of damaged and necrotic cells as suggested by renal tubular epithelial tissue sections. In addition, there was an increase in the pyroptosis-related markers expression and pyroptosis-induced cell death. Consistently, studies in vitro found that GM significantly induced pyroptosis and its associated protein expression in NRK52e cells. Whereas, the administration of Bufalin reversed these effects of GM in vivo and in vitro. Further, we found that Nigericin (NLRP3 agonist) could reversed the effects of bufalin on GM-induced pyroptosis.

CONCLUSION

Bufalin attenuates pyroptosis generated AKI by inhibiting NLRP3 inflammasome.

Computational Systems Pharmacology and Molecular Docking Reveal an Anti-Apoptosis and Anti-Inflammatory Mechanism of Compound Angelica Ligusticum Wallichii Granules in the Treatment of Endometriosis

Background

Traditional medicine is a common treatment option for endometrioid-related symptoms. In the past few decades, Guixiong Xiaoyi formula has been widely used as a traditional medicine for the treatment of endometriosis.

Purpose

This study aimed to prepare compound Angelica Ligusticum wallichii granule (CALG) by modern technological methods and to study its pharmacodynamics and mechanisms of treating endometriosis.

Methods

The ingredients of CALG were determined by UPLC-Q-TOF/MS. Target prediction of compounds and diseases was performed using databases, and the mechanisms of CALG were predicted by Gene Ontology and Kyoto Encyclopedia of Genes and Genomes and verified by molecular docking. Furthermore, a rat model of endometriosis was established to study the effects of CALG on endometriosis in vivo.

Results

CALG with good specificity, durability, and stability was obtained following a detailed preparation process and quality control standard. Using network systems pharmacology, 109 chemical compositions and 104 core targets were identified for the treatment of endometriosis. The composition-target-channel-disease network topology analysis of the top 15 chemical compositions of CALG showed that the beneficial effect of CALG on endometriosis was attributed to phenolic compounds. In addition, CALG treatment reduced the volume of ectopic uterine lesions, promoted apoptosis, inhibited the secretion of inflammatory cytokines, and increased HIF-1 expression in rats with endometriosis.

Conclusion

CALG induces apoptosis and inhibits inflammation and is a promising drug for the treatment of endometriosis.

MELTF Might Regulate Ferroptosis, Pyroptosis, and Autophagy in Platelet-Rich Plasma-Mediated Endometrial Epithelium Regeneration

The endometrial basal layer is essential for endometrial regeneration, whose disruption leads to thin endometrium or intrauterine adhesion (IUA) with an unsatisfactory prognosis. Emerging data indicate that platelet-rich plasma (PRP) can promote endometrial proliferation, but the mechanism by which PRP regulates endometrial regeneration remains unclear. Herein, we investigated the therapeutic effects and possible mechanisms of PRP on endometrial regeneration. IUA animal model was generated by sham, mechanically damaging endometrium with or without PRP for 10 days. The uterine section in the model group showed degenerative changes with a narrow endometrial lumen, atrophic columnar epithelium, decreased number of endometrial glands, decreased endometrial thickness, and increased collagen deposition. The above disruption could be ameliorated by the PRP. Transcriptome sequencing analysis displayed that the retinol metabolism pathway and extracellular matrix (ECM) receptor interaction pathway were up-regulated and enriched in differential expression genes (DEGs). Melanotransferrin (MELTF) was the key up-regulated gene in PRP-induced endometrial regeneration, which was verified in vivo and in vitro. Ferroptosis, autophagy, and pyroptosis were down-regulated in PRP-treated Ishikawa cells. Conclusively, PRP promotes endometrium regeneration by up-regulating the retinol metabolism and ECM receptor interaction pathway with MELTF. Meanwhile, PRP could also inhibit endometrial epithelial cell death by regulating ferroptosis, autophagy, and pyroptosis.

Comparative transcriptomes of three different skin sites for the Asiatic toad (Bufo gargarizans)

Toads release toxic dry secretions from glands in their skin. Toxin possesses a wide range of biological effects, but little is known about its specific gene expression pattern and regulatory mechanisms. The Asiatic toad (Bufo gargarizans) is widely used to produce toxin. Here, we explored the gene expression of 30 tissue samples from three different skin sites (parotoid gland, dorsal skin, and abdomen skin) of B. gargarizans. After de novo assembly, 783,130 unigenes with an average length of 489 bp (N50 = 556 bp) were obtained. A total of 9,248 significant differentially expressed genes (DEGs) were detected. There were 8,819 DEGs between the parotoid gland and abdomen skin and 1,299 DEGs between the dorsal skin and abdomen skin, while only 1,283 DEGs were obtained between the parotoid gland and dorsal skin. Through enrichment analysis, it was found that the detected differential gene expressions corresponded to the different functions of different skin sites. Our key findings were the genetic expression of toxin secretion, the protection function of skin, and the related genes such as HSD3B, Cyp2c, and CAT, LGALS9. In conclusion, we provide useful transcript resources to study the gene expression and gene function of B. gargarizans and other amphibians. The detected DEGs between different sites of the skin provided better insights into the genetic mechanisms of toxin secretion and the protection function of skin for amphibians.

Levels of endoplasmic reticulum stress-related mRNA in peritoneal fluid of patients with endometriosis or gynaecological cancer

OBJECTIVE

To compare the levels of endoplasmic reticulum (ER) stress-associated mRNAs and the clinical characteristics of patients with endometriosis or gynaecological cancer.

METHODS

This prospective study obtained intraperitoneal fluid samples from female patients that underwent surgery. The levels of ER stress mRNAs in the peritoneal fluid, including C/EBP-homologous protein (CHOP), X-box binding protein 1 (sXBP1), activating transcription factor 6 (ATF6), immunoglobulin heavy chain-binding protein (BiP), inositol-requiring enzyme 1α (IRE1α) and protein kinase RNA-like endoplasmic reticulum kinase (PERK), were measured using real-time reverse transcription-polymerase chain reaction in patients with benign disease without endometriosis (control group), with endometriosis or with gynaecological cancer.

RESULTS

This study enrolled 126 patients: 46 control patients; 47 with endometriosis; and 33 with cancer. The levels of CHOP and BiP mRNA were significantly higher in the control group compared with the cancer group. Levels of sXBP1 and ATF6 mRNA were significantly higher in the cancer group than in the control and endometriosis groups. In the endometriosis group, ATF6 mRNA level was inversely correlated with age and positively correlated with serum cancer antigen 125 levels; and ATF6 and PERK mRNA levels were inversely correlated with parity.

CONCLUSION

The levels of ER stress-related mRNAs were related to the pathogenesis of endometriosis and gynaecological cancers.

Natural products are an important source for proteasome regulating agents

BACKGROUND

Natural medicines have a long history in the prevention and treatment of various diseases in East Asian region, especially in China. Modern research has proved that the pharmacological effects of numerous natural medicines involve the participation of ubiquitin proteasome system (UPS). UPS can degrade the unwanted and damaged proteins widely distributed in the nucleus and cytoplasm of various eukaryotes.

PURPOSE

The objective of the present study was to review and discuss the regulatory effects of natural products and extracts on proteasome components, which may help to find new proteasome regulators for drug development and clinical applications.

METHODS

The related information was compiled using the major scientific databases, such as CNKI, Elsevier, ScienceDirect, PubMed, SpringerLink, Wiley Online, and GeenMedical. The keywords "natural product" and "proteasome" were applied to extract the literature. Nature derived extracts, compounds and their derivatives involved in proteasome regulation were included, and the publications related to synthetic proteasome agents were excluded.

RESULTS

The pharmacological effects of more than 80 natural products and extracts derived from phytomedicines related to the proteasome regulation were reviewed. These natural products were classified according to their chemical properties. We also summarized some laws of action of natural products as proteasome regulators in the treatment of diseases, and listed the action characteristics of the typical natural products.

CONCLUSION

Natural products derived from nature can induce the degradation of damaged proteins through UPS or act as regulators to directly regulate the activity of proteasome. But few proteasome modulators are applied clinically. Summary of known rules for proteasome modulators will contribute to discover, modify and synthesize more proteasome modulators for clinical applications.

Molecular dysregulations underlying the pathogenesis of endometriosis

Endometriosis is a crippling disease characterized by the presence of endometrium-like tissue or scar outside the uterine cavity, commonly confined to the peritoneal and serosal surfaces of the pelvic organs. 10-15% of women in reproductive age are estimated to be affected by endometriosis. Most of these patients present with infertility and suffer from pelvic pain. The benign disease rarely progresses to malignancy. Regardless of its high prevalence, the pathogenesis of the disease is not fully understood. Treatment options for endometriosis are limited and are often based on a symptomatic approach. The unavailability of proper diagnostic approaches, fewer therapeutic options, and sparse understanding of molecular alterations are responsible for the continued disease burden. Exploring the molecular elements causing the pathogenesis of endometriosis may lead to a number of breakthroughs in the treatment of the illness, such as the discovery of new biomarkers for diagnosis and therapeutic targets that can be a guide to better prognosis and reduced recurrence. The goal of this review is to provide the reader a critical understanding of the disease by summarizing the genetic, immunological, hormonal, and epigenetic deregulations that support the molecular basis for development of endometriotic cyst, with a special focus on the study models needed to analyze these changes in the endometriotic microenvironment.

Differences in growth and vascularization of ectopic menstrual and non-menstrual endometrial tissue in mouse models of endometriosis

STUDY QUESTION

Is there a difference in the growth and vascularization between murine endometriotic lesions originating from menstrual or non-menstrual endometrial fragments?

SUMMARY ANSWER

Endometriotic lesions developing from menstrual and non-menstrual tissue fragments share many similarities, but also exhibit distinct differences in growth and vascularization, particularly under exogenous estrogen stimulation.

WHAT IS KNOWN ALREADY

Mouse models are increasingly used in endometriosis research. For this purpose, menstrual or non-menstrual endometrial fragments serve for the induction of endometriotic lesions. So far, these two fragment types have never been directly compared under identical experimental conditions.

STUDY DESIGN, SIZE, DURATION

This was a prospective experimental study in a murine peritoneal and dorsal skinfold chamber model of endometriosis. Endometrial tissue fragments from menstruated (n = 15) and non-menstruated (n = 21) C57BL/6 mice were simultaneously transplanted into the peritoneal cavity or dorsal skinfold chamber of non-ovariectomized (non-ovx, n = 17), ovariectomized (ovx, n = 17) and ovariectomized, estrogen-substituted (ovx+E2, n = 17) recipient animals and analyzed throughout an observation period of 28 and 14 days, respectively.

PARTICIPANTS/MATERIALS, SETTING, METHODS

The engraftment, growth and vascularization of the newly developing endometriotic lesions were analyzed by means of high-resolution ultrasound imaging, intravital fluorescence microscopy, histology and immunohistochemistry.

MAIN RESULTS AND THE ROLE OF CHANCE

Menstrual and non-menstrual tissue fragments developed into peritoneal endometriotic lesions without differences in growth, microvessel density and cell proliferation in non-ovx mice. Lesion formation out of both fragment types was markedly suppressed in ovx mice. In case of non-menstrual tissue fragments, this effect could be reversed by estrogen supplementation. In contrast, endometriotic lesions originating from menstrual tissue fragments exhibited a significantly smaller volume in ovx+E2 mice, which may be due to a reduced hormone sensitivity. Moreover, menstrual tissue fragments showed a delayed vascularization and a reduced blood perfusion after transplantation into dorsal skinfold chambers when compared to non-menstrual tissue fragments, indicating different vascularization modes of the two fragment types. To limit the role of chance, the experiments were conducted under standardized laboratory conditions. Statistical significance was accepted for a value of P < 0.05.

LARGE SCALE DATA

N/A.

LIMITATIONS, REASONS FOR CAUTION

Endometriotic lesions were induced by syngeneic tissue transplantation into recipient mice without the use of pathological endometriotic tissue of human nature. Therefore, the results obtained in this study may not fully relate to human patients with endometriosis.

WIDER IMPLICATIONS OF THE FINDINGS

The present study significantly contributes to the characterization of common murine endometriosis models. These models represent important tools for studies focusing on the basic mechanisms of endometriosis and the development of novel therapeutic strategies for the treatment of this frequent gynecological disease. The presented findings indicate that the combination of different experimental models and approaches may be the most appropriate strategy to study the pathophysiology and drug sensitivity of a complex disease such as endometriosis under preclinical conditions.

STUDY FUNDING/COMPETING INTEREST(S)

There was no specific funding of this study. The authors have no conflicts of interest to declare.

Molecular and Clinical Insights on the Complex Interaction between Oxidative Stress, Apoptosis, and Endobiota in the Pathogenesis of Endometriosis

Endometriosis (EMS) remains, to date, an intriguing and debilitating gynecological disorder that possesses a multifactorial substrate. Recent studies with the objective of elucidating its etiology highlighted the antagonistic effect of EMS on a multiple of processes involved in homeostasis. Although the current oxidative biomarkers clearly reveal the consequences induced by EMS, its implication in the associated inflammatory reactions could be much more complex. Besides the overproduction of reactive oxygen species (ROS) that leads to an exacerbated oxidative response, it also changes the normal expression of several pro-inflammatory modulators, reflected by the fluctuating activity of several pro- and anti-apoptotic mediators whose expression is impaired. In light of this topic, several studies elucidate the involvement of apoptosis in EMS, being brought controversial findings, even reports with no significant change. Further, some authors reported an abnormal expression of multiple genes that are crucial for the overall functionality of the female reproductive system. Cumulatively, it seems that the subsequent oxidative imbalance and apoptosis process impairment could further disrupt the normal removal of unnecessary biological products. Based on all gathered evidence, we could argue that the related stress state could determine human endobiota impairment, which could further participate in the inflammatory and main antioxidant enzyme changes occurring in EMS. Moreover, a correlation between endobiota integrity, inflammation, and oxidative stress (OS) was suggested in relation to the possible predisposition to pathogen determined infections.

Steroid receptor coactivator-1: The central intermediator linking multiple signals and functions in the brain and spinal cord

The effects of steroid hormones are believed to be mediated by their nuclear receptors (NRs). The p160 coactivator family, including steroid receptor coactivator-1 (SRC-1), 2 and 3, has been shown to physically interact with NRs to enhance their transactivational activities. Among which SRC-1 has been predominantly localized in the central nervous system including brain and spinal cord. It is not only localized in neurons but also detectable in neuroglial cells (mainly localized in the nuclei but also detectable in the extra-nuclear components). Although the expression of SRC-1 is regulated by many steroids, it is also regulated by some non-steroidal factors such as injury, sound and light. Functionally, SRC-1 has been implied in normal function such as development and ageing, learning and memory, central regulation on reproductive behaviors, motor and food intake. Pathologically, SRC-1 may play a role in the regulation of neuropsychiatric disorders (including stress, depression, anxiety, and autism spectrum disorder), metabolite homeostasis and obesity as well as tumorigenesis. Under most conditions, the related mechanisms are far from elucidation; although it may regulate spatial memory through Rictor/mTORC2-actin polymerization related synaptic plasticity. Several inhibitors and stimulator of SRC-1 have shown anti-cancer potentials, but whether these small molecules could be used to modulate ageing and central disorder related neuropathology remain unclear. Therefore, to elucidate when and how SRC-1 is turned on and off under different stimuli is very interesting and great challenge for neuroscientists.

E3 ubiquitin ligase TRIM24 deficiency promotes NLRP3/caspase-1/IL-1β-mediated pyroptosis in endometriosis

Endometriosis is an inflammation-dependent disease that shares similarities with malignant tumors including attachment and infiltration. Tripartite motif-containing 24 (TRIM24) has been illustrated in inflammatory responses and gynecological tumors, and Nod-like receptor protein 3 (NLRP3) inflammasome has been implicated in endometriosis. However, the involvement of TRIM24 and the role of NLRP3/caspase-1/interleukin-1β (IL-1β)-mediated pyroptosis in endometriosis remain obscure. In this study, we originally detected the decreased expression of TRIM24 in the ectopic endometrium of endometriosis compared with the normal endometrium. Then we measured the promoted protein expression of pyroptotic biomarkers (NLRP3, procaspase-1, caspase-1, pro-IL-1β, and IL-1β) using Western blot analysis and the stimulated secretion of IL-1β and IL-18 by enzyme-linked immunosorbent assay in ectopic human endometrial stromal cells (hESC) compared with normal hESC. TRIM24-small-interfering RNA (siTRIM24) was used to silence TRIM24, whereas TRIM24-pcDNA3.1 was used for overexpressing TRIM24. The migration of hESC was determined by a Transwell migration assay. Coimmunoprecipitation and ubiquitination analyses were conducted to explore the interaction between TRIM24 and NLRP3. Subsequently, we found that TRIM24 negatively regulated NLRP3/caspase-1/IL-1β-mediated pyroptosis and cell migration of hESC, and CY-09, the specific inhibitor of NLRP3, could reverse the promoted pyroptosis and cell migration induced by siTRIM24. Furthermore, TRIM24 interacted with NLRP3 and the upregulation of TRIM24 facilitated the ubiquitination of NLRP3 in ectopic hESC. Our findings suggest that TRIM24 may participate in the progression of endometriosis through the NLRP3/caspase-1/IL-1β-mediated pyroptotic pathway via ubiquitination of NLRP3, which reveals the significant molecular mechanism underlying endometriosis.

Pyroptosis and inflammasomes in obstetrical and gynecological diseases

Pyroptosis, an inflammatory form of programmed cell death, takes an essential part in a wide variety of physiological activities, for instance, implantation, placentation and the body's defense against infection. However, once excessively activated, pyroptosis mediated by the activation of inflammasomes can be highly pathological. It can cause inflammatory and autoimmune diseases including a variety of obstetrical and gynecological diseases, such as endometriosis, gestational diabetes mellitus, insulin resistance in polycystic ovary syndrome, and multiple obstetric complications including preeclampsia. Although the role of pyroptosis in the pathogenesis of the above mentioned diseases has not been fully elucidated, we try to tap its therapeutic potential by targeting pyroptosis signaling and inflammasome formation. Pyroptosis and inflammasomes are confirmed to be involved in endometriosis and gynecological malignant tumors, therefore, medical approachs inducing pyroptosis of the ectopic endometrium and tumor cells can be feasible treatments for endometriosis and gynecological cancers. On the maternal-fetal interface, although a certain level of the innate immune response activation is required for a successful implantation and placentation, maternal and fetal injury may occur once the inflammasomes are over-activated. Besides, since gestational diabetes mellitus and insulin resistance in polycystic ovary syndrome share common pathogenesis with metabolic diseases, this domain research sheds light on future study of some obstetrical and gynecological diseases.

Toxic Animal-Based Medicinal Materials Can Be Effective in Treating Endometriosis: A Scoping Review

Animal toxins and venoms have recently been developed as cancer treatments possessing tumor cell growth-inhibitory, antiangiogenesis, and proapoptotic effects. Endometriosis is a common benign gynecological disorder in reproductive-age women, and no definite treatment for this disorder is without severe side effects. As endometriosis and malignant tumors share similar characteristics (progressive, invasive, estrogen-dependent growth, and recurrence), animal toxins and venoms are thought to be effective against endometriosis. The objective of this study was to outline studies using toxic animal-based medicinal materials (TMM) as endometriosis treatment and to explore its clinical applicability. Preclinical and clinical studies using TMM were searched for in four databases from inception to October 2020. A total of 20 studies of TMM on endometriosis were included. In eight clinical studies, herbal medicines containing TMM were effective in relieving symptoms of endometriosis, with no side effects. In twelve experimental studies, the main therapeutic mechanisms of TMM against endometriosis were proapoptotic, antiangiogenesis, estrogen level-reducing, and possible anti-inflammatory effects. TMM are thus considered promising sources for the development of an effective treatment method for endometriosis. Further studies are needed to clarify the therapeutic mechanism of TMM against endometriosis and to provide sufficient grounds for clinical application.

Kiwi Root Extract Inhibits the Development of Endometriosis in Mice by Downregulating Inflammatory Factors

Purpose

To determine whether the kiwi root extract inhibits the development of endometriosis in mice by suppressing inflammatory factors.

Materials and Methods

The mouse model of endometriosis was induced by surgery after which the mice were continuously injected with the drug for 14 days. On the 14^th day, the mice were sacrificed, and the peritoneal fluid was obtained for enzyme-linked immunosorbent assay. Endometrial ectopic tissue was weighed and analyzed by tissue immunochemistry, RT-PCR, western blotting, and gelatin zymography experiment.

Results

Kiwi root extract significantly reduced endometriotic lesion volume and downregulated the proinflammatory cytokines IL-6, IL-8, IL-1β, and TNF-α, as well as the angiogenic factor VEGF-A. It also inhibited the mRNA and protein expression of COX-1 and COX-2, IL-6, TGF-β1, EP₂ receptor, and ER-β in endometriotic lesions but did not affect the expression of MMP-9 and MMP-2.

Conclusions

Kiwi root extract could significantly inhibit the growth of surgery-induced endometriosis in mice. Our results suggest that the kiwi root extract may inhibit the development and progression of ectopic endometrium through disruption of neovascularization and reducing inflammation, which may be beneficial in treating this common gynecological disease.

Exposure to mono (2-ethylhexyl) phthalate facilitates apoptosis and pyroptosis of human endometrial microvascular endothelial cells through NLRP3 inflammasome

Mono (2-ethylhexyl) phthalate (MEHP) is a major metabolite of di (2-ethylhexyl) phthalate (DEHP). This study aimed to observe the toxic effect of MEHP on human endometrial microvascular endothelial cells (HEMECs) and its potential molecular mechanism. HEMECs were exposed to different concentrations of MEHP (0, 50, 100, and 200 nM). Cell viability and apoptosis were assessed by cell counting kit-8 (CCK-8) and flow cytometry assays. Western blot was performed to examine the expression of apoptosis-related proteins (Bcl-2, Bax, and Caspase-3). Moreover, the expression of pyroptosis-related Caspase-1 was detected by western blot and immunofluorescence assays. Lactate dehydrogenase (LDH) release levels were evaluated in HEMECs treated with MEHP and/or Caspase-1 inhibitor Ac-YVAD-CHO. After exposure to MEHP, NLRP3 expression was examined by reverse transcription quantitative polymerase chain reaction (RT-qPCR) and western blot. LDH release and apoptosis levels were tested in HEMECs induced by MEHP and/or siNLRP3. MEHP significantly induced cell viability and inhibited apoptosis for HEMECs, with a concentration-dependent manner. Furthermore, Bcl-2/Bax ratio was distinctly reduced and Caspase-3 expression was increased in HEMECs after exposure to MEHP. Western blot and immunofluorescence results confirmed that MEHP markedly augmented Caspase-1 expression in HEMECs. Furthermore, LDH release levels were fortified in HEMECs treated with MEHP, which were improved following cotreatment with Ac-YVAD-CHO. At the mRNA and protein levels, NLRP3 expression was prominently increased in HEMECs exposed to MEHP. NLRP3 knockdown markedly ameliorated the increase in LDH release and apoptosis induced by MEHP exposure in HEMECs. Our findings suggested that exposure to MEHP facilitates apoptosis and pyroptosis of HEMECs through NLRP3 inflammasome.

Endometriosis and nuclear receptors

BACKGROUND

Endometriosis is recognized as a steroid-dependent disorder; however, the precise roles of nuclear receptors (NRs) in steroid responsiveness and other signaling pathways are not well understood.

OBJECTIVE AND RATIONALE

Over the past several years, a number of paradigm-shifting breakthroughs have occurred in the area of NRs in endometriosis. We review and clarify new information regarding the mechanisms responsible for: (i) excessive estrogen biosynthesis, (ii) estrogen-dependent inflammation, (iii) defective differentiation due to progesterone resistance and (iv) enhanced survival due to deficient retinoid production and action in endometriosis. We emphasize the roles of the relevant NRs critical for these pathological processes in endometriosis.

SEARCH METHODS

We conducted a comprehensive search using PubMed for human, animal and cellular studies published until 2018 in the following areas: endometriosis; the steroid and orphan NRs, estrogen receptors alpha (ESR1) and beta (ESR2), progesterone receptor (PGR), steroidogenic factor-1 (NR5A1) and chicken ovalbumin upstream promoter-transcription factor II (NR2F2); and retinoids.

OUTCOMES

Four distinct abnormalities in the intracavitary endometrium and extra-uterine endometriotic tissue underlie endometriosis progression: dysregulated differentiation of endometrial mesenchymal cells, abnormal epigenetic marks, inflammation activated by excess estrogen and the development of progesterone resistance. Endometriotic stromal cells compose the bulk of the lesions and demonstrate widespread epigenetic abnormalities. Endometriotic stromal cells also display a wide range of abnormal NR expression. The orphan NRs NR5A1 and NR2F2 compete to regulate steroid-synthesizing genes in endometriotic stromal cells; NR5A1 dominance gives rise to excessive estrogen formation. Endometriotic stromal cells show an abnormally low ESR1:ESR2 ratio due to excessive levels of ESR2, which mediates an estrogen-driven inflammatory process and prostaglandin formation. These cells are also deficient in PGR, leading to progesterone resistance and defective retinoid synthesis. The pattern of NR expression, involving low ESR1 and PGR and high ESR2, is reminiscent of uterine leiomyoma stem cells. This led us to speculate that endometriotic stromal cells may display stem cell characteristics found in other uterine tissues. The biologic consequences of these abnormalities in endometriotic tissue include intense inflammation, defective differentiation and enhanced survival.

WIDER IMPLICATIONS

Steroid- and other NR-related abnormalities exert genome-wide biologic effects via interaction with defective epigenetic programming and enhance inflammation in endometriotic stromal cells. New synthetic ligands, targeting PGR, retinoic acid receptors and ESR2, may offer novel treatment options.

Endometriosis - a decade later - still an enigmatic disease. What is the new in the diagnosis and treatment?

Endometriosis is a common disease in women of reproduction age. It causes pain and difficulty in getting pregnant. However the exact causes of infertility associated with endometriosis still remain controversial. The treatment of endometriosis consists of medical treatment of pain as well as medical and surgical treatment of infertility caused by endometriosis and assisted reproduction techniques. Since the treatment of endometriosis is often connected with diminishing ovarian reserve, the techniques for ovarian tissue preservation and oocyte and embryo freezing are used to maintain the ability for childbearing.

Progesterone and Estrogen Signaling in the Endometrium: What Goes Wrong in Endometriosis?

In the healthy endometrium, progesterone and estrogen signaling coordinate in a tightly regulated, dynamic interplay to drive a normal menstrual cycle and promote an embryo-receptive state to allow implantation during the window of receptivity. It is well-established that progesterone and estrogen act primarily through their cognate receptors to set off cascades of signaling pathways and enact large-scale gene expression programs. In endometriosis, when endometrial tissue grows outside the uterine cavity, progesterone and estrogen signaling are disrupted, commonly resulting in progesterone resistance and estrogen dominance. This hormone imbalance leads to heightened inflammation and may also increase the pelvic pain of the disease and decrease endometrial receptivity to embryo implantation. This review focuses on the molecular mechanisms governing progesterone and estrogen signaling supporting endometrial function and how they become dysregulated in endometriosis. Understanding how these mechanisms contribute to the pelvic pain and infertility associated with endometriosis will open new avenues of targeted medical therapies to give relief to the millions of women suffering its effects.

GZFLW Induces Apoptosis of Ectopic Endometrial Stromal Cells via Promoting VPS53 Protein Stability

Endometriosis is still a major problem in obstetrics and gynecology. While GZFLW (Gui Zhi Fu Ling Wan) has been originally used for treating gynecological diseases, however, the molecular mechanism that GZFLW acts on endometriosis is not clear. To investigate the molecular mechanism that GZFLW plays role on endometriosis, iTRAQ (isobaric tags for relative and absolute quantification) proteomics and human endometrial stromal cells (Y14) obtained from a patient with endometriosis were used in in vitro study. Our results demonstrated that GZFLW decreased Y14 cells proliferation while increased cells apoptosis. The differential expression protein VPS53 (Vacuolar protein sorting 53 homolog) was predicted by iTRAQ coupled LC-MS/MS and further identified by western blot. Besides, GZFLW induced VPS53 protein level by promoting its stabilization. Our findings highlight a novel role for VPS53 in gynecology and provide a potent therapeutic strategy against endometriosis.