Tetramethylpyrazine Retards the Progression and Fibrogenesis of Endometriosis

Tetramethylpyrazine Confers Protection Against Oxidative Stress and NLRP3-Dependent Pyroptosis in Rats with Endometriosis

Tetramethylpyrazine (TMP) has been confirmed to suppress inflammation in endometriosis (EMs). Herein, this study investigated whether and how TMP affected NLRP3 inflammasomes and oxidative stress in EMs. After establishment of an EMs rat model, rats were treated with different concentrations of TMP. The size of endometriotic lesions and the latency and frequency of torsion in rats were recorded, followed by the measurement of relevant indicators (TNF-α, IL-6, IL-2, IL-10, MDA, SOD, GSH, CAT, ROS, NLRP3, ASC, GSDMD, caspase-1, Nrf2, and HO-1). The study experimentally determined that TMP treatment markedly decreased the size of endometriotic lesions and improved torsion in rats with EMs. The levels of inflammatory proteins, oxidative stress markers, NLRP3 inflammasome, and pyroptotic proteins were elevated in rats with EMs, all of which were reversed upon TMP treatment. Additionally, the activities of SOD, GSH, and CAT were lowered in rats with EMs, which were partly abrogated by TMP treatment. Furthermore, the downregulation of Nrf2 and HO-1 was counteracted by TMP treatment. To sum up, TMP represses excessive oxidative stress, NLRP3 inflammasome activation, and pyroptosis in rats with EMs. Additionally, TMP may activate the Nrf2/HO-1 pathway.

Synergistic inhibitory effects of tetramethylpyrazine and evodiamine on endometriosis development

Endometriosis (EMS) belongs to a gynecological disorder with inflammation and the existence of endometrial-like tissues beyond the uterus, often leading to infertility and pelvic pain. Estrogen receptor β (ERβ) is significantly expressed in endometriosis (EMS) and recognized as a promising therapeutic target for EMS treatment by inhibiting ERβ activity. In this study, we investigated the potential mechanisms for tetramethylpyrazine (TMP)-mediated ERβ suppression, and the synergistic inhibitory effect of TMP and evodiamine (EVO) on ERβ expression and EMS development. We found that TMP suppresses ERβ expression by reducing the association of Oct3/4 with the ERβ promoter and decreasing Oct3/4 protein levels without affecting Oct3/4 transcript levels. A minimum dosage of 10 µM TMP is required to inhibit ERβ expression. Neither TMP (5 µM) nor EVO (2 µM) alone had any effect, but their combination synergistically inhibited ERβ expression and modulated related cellular processes, including redox balance, mitochondrial function, inflammation, and proliferation. Additionally, the combination of TMP (10 mg/kg body weight) and EVO (5 mg/kg) synergistically inhibited ERβ expression and EMS development in the mouse model. In conclusion, TMP suppresses ERβ expression by reducing the association of Oct3/4 with the ERβ promoter. Neither TMP nor EVO alone effectively suppresses ERβ in both laboratory and live organism models. However, their combination synergistically inhibits ERβ expression and EMS development, suggesting a potential therapeutic strategy for EMS using TMP and EVO.

The role of fibrosis in endometriosis: a systematic review

BACKGROUND

Fibrosis is an important pathological feature of endometriotic lesions of all subtypes. Fibrosis is present in and around endometriotic lesions, and a central role in its development is played by myofibroblasts, which are cells derived mainly after epithelial-to-mesenchymal transition (EMT) and fibroblast-to-myofibroblast transdifferentiation (FMT). Transforming growth factor-β (TGF-β) has a key role in this myofibroblastic differentiation. Myofibroblasts deposit extracellular matrix (ECM) and have contracting abilities, leading to a stiff micro-environment. These aspects are hypothesized to be involved in the origin of endometriosis-associated pain. Additionally, similarities between endometriosis-related fibrosis and other fibrotic diseases, such as systemic sclerosis or lung fibrosis, indicate that targeting fibrosis could be a potential therapeutic strategy for non-hormonal therapy for endometriosis.

OBJECTIVE AND RATIONALE

This review aims to summarize the current knowledge and to highlight the knowledge gaps about the role of fibrosis in endometriosis. A comprehensive literature overview about the role of fibrosis in endometriosis can improve the efficiency of fibrosis-oriented research in endometriosis.

SEARCH METHODS

A systematic literature search was performed in three biomedical databases using search terms for 'endometriosis', 'fibrosis', 'myofibroblasts', 'collagen', and 'α-smooth muscle actin'. Original studies were included if they reported about fibrosis and endometriosis. Both preclinical in vitro and animal studies, as well as research concerning human subjects were included.

OUTCOMES

Our search yielded 3441 results, of which 142 studies were included in this review. Most studies scored a high to moderate risk of bias according to the bias assessment tools. The studies were divided in three categories: human observational studies, experimental studies with human-derived material, and animal studies. The observational studies showed details about the histologic appearance of fibrosis in endometriosis and the co-occurrence of nerves and immune cells in lesions. The in vitro studies identified several pro-fibrotic pathways in relation to endometriosis. The animal studies mainly assessed the effect of potential therapeutic strategies to halt or regress fibrosis, for example targeting platelets or mast cells.

WIDER IMPLICATIONS

This review shows the central role of fibrosis and its main cellular driver, the myofibroblast, in endometriosis. Platelets and TGF-β have a pivotal role in pro-fibrotic signaling. The presence of nerves and neuropeptides is closely associated with fibrosis in endometriotic lesions, and is likely a cause of endometriosis-associated pain. The process of fibrotic development after EMT and FMT shares characteristics with other fibrotic diseases, so exploring similarities in endometriosis with known processes in diseases like systemic sclerosis, idiopathic pulmonary fibrosis or liver cirrhosis is relevant and a promising direction to explore new treatment strategies. The close relationship with nerves appears rather unique for endometriosis-related fibrosis and is not observed in other fibrotic diseases.

REGISTRATION NUMBER

N/A.

Protective effects of tetramethylpyrazine on myocardial ischemia/reperfusion injury involve NLRP3 inflammasome suppression by autophagy activation

Tetramethylpyrazine (TMP) belongs to the active ingredients of the traditional Chinese medicine Chuanxiong, which has a certain protective effect in myocardial ischemia-reperfusion (I/R) injury. It can improve postoperative cardiac function and alleviate ventricular remodeling in acute myocardial infarction patients. However, its specific protective mechanism is still unclear. In this study, a certain concentration of TMP was introduced into I/R mice or H9C2 cells after oxygen-glucose deprivation/reoxygenation (OGD/R) treatment to observe the effects of TMP on cardiomyocyte activity, cytotoxicity, apoptosis, autophagy, pyroptosis, and NLRP3 inflammasome activation. The results displayed that TMP intervention could reduce OGD/R and I/R-induced cardiomyocyte apoptosis, accelerate cellular activity and autophagy levels, and ameliorate myocardial tissue necrosis in I/R mice in a dose-dependent manner. Further, TMP prevented the formation of NLRP3 inflammasomes to suppress pyroptosis by increasing the level of cardiomyocyte autophagy after I/R and OGD/R modelling, the introduction of chloroquine to suppress autophagic activity in vivo and in vitro was further analyzed to confirm whether TMP inhibits NLRP3 inflammasome activation and pyroptosis by increasing autophagy, and we found the inhibitory effect of TMP on NLRP3 inflammasomes and its protective effect against myocardial injury were blocked when autophagy was inhibited with chloroquine. In conclusion, this experiment demonstrated that TMP unusually attenuated I/R injury in mice, and this protective effect was achieved by inhibiting the activation of NLRP3 inflammasomes through enhancing autophagic activity.

Therapeutic Potential of Natural Resources Against Endometriosis: Current Advances and Future Perspectives

Endometriosis (EMS) is defined as the appearance, growth, infiltration, and repeated bleeding of endometrioid tissue (glands and stroma) outside the uterus cavity, which can form nodules and masses. Endometriosis is a chronic inflammatory estrogen-dependent disease and occurs in women of reproductive age. This disorder may significantly affect the quality of life of patients. The pathogenic processes involved in the development and maintenance of endometriosis remain unclear. Current treatment options for endometriosis mainly include drug therapy and surgery. Drug therapy mainly ties to the use of non-steroidal anti-inflammatory drugs (NSAIDs) and hormonal drugs. However, these drugs may produce adverse effects when used for long-term treatment of endometriosis, such as nausea, vomiting gastrointestinal reactions, abnormal liver and kidney function, gastric ulcers, and thrombosis. Although endometriosis lesions can be surgically removed, the disease has a high recurrence rate after surgical resection, with a recurrence rate of 21.5% within 2 years and 40% to 50% within 5 years. Thus, there is an urgent need to develop alternative or additional therapies for the treatment of endometriosis. In this review, we give a systematic summary of therapeutic multiple component prescriptions (including traditional Chinese medicine and so on), bioactive crude extracts of plants/herbs and purified compounds and their newly found mechanisms reported in literature in recent years against endometriosis.

Progress on the Synthesis Pathways and Pharmacological Effects of Naturally Occurring Pyrazines

As one of the most essential types of heterocyclic compounds, pyrazines have a characteristic smell and taste and have a wide range of commercial applications, especially in the food industry. With the development of the food industry, the demand for pyrazines has increased. Therefore, understanding the properties, functions, and synthetic pathways of pyrazines is one of the fundamental methods to produce, control, and apply pyrazines in food or medical systems. In this review, we provide an overview of the synthesis pathways and physiological or pharmacological functions of naturally occurring pyrazines. In particular, we focus on the biosynthesis and pharmacological effects of 2,3,5,6-Tetramethylpyrazine (TTMP), 2,5-Dimethylpyrazine (2,5-DMP), and 2,3,5-trimethylpyrazine (TMP). Furthermore, areas where further research on pyrazines is needed are discussed in this work.

Exploring the role of Chinese herbal medicine in the long-term management of postoperative ovarian endometriotic cysts: a systematic review and meta-analysis

Background

Ovarian endometriotic cysts (OEC) represent the primary manifestation of endometriosis, constituting a hormonally dependent inflammatory disorder in gynecology. It significantly affects the quality of life and reproductive health of women. It is worth noting that traditional Chinese medicine (TCM), especially Chinese herbal medicine (CHM), has been widely applied in mainland China due to its unique therapeutic system and commendable clinical efficacy, bringing new hope for preventing and managing OEC.

Objective

This study aims to evaluate the efficacy and safety of CHM in the management of postoperative OEC. Simultaneously, it seeks to explore the medication laws, therapeutic principles, and specific treatment mechanisms of CHM.

Methods

Eight electronic databases were searched from their inception to 01 November 2023. Randomized controlled trials (RCTs) assessing the therapeutic effects and safety of CHM for postoperative OEC were included. The risk of bias for each trial was assessed using the Cochrane Collaboration's tool. The certainty of the evidence was evaluated using the GRADE profiler 3.2. Additionally, we extracted formulation from the included studies, conducting a thorough analysis.

Results

(ⅰ) Twenty-two RCTs involving 1938 patients were included. In terms of the primary efficacy outcome, the CHM group demonstrated a potentially lower recurrence rate compared to both control (odds ratio (OR) = 0.25; 95% confidence intervals (CI): 0.10-0.64) and conventional western medicine (CWM) (OR = 0.26; 95% CI: 0.11-0.65) groups. Furthermore, the joint application of CHM and CWM resulted in a significant reduction in the recurrence rate (OR = 0.26; 95% CI: 0.17-0.40). (ⅱ) Regarding secondary efficacy outcomes, (a) Total clinical efficacy rate: CHM showcased an augmentation in clinical effectiveness compared to both the control (OR = 4.23; 95% CI: 1.12-15.99) and CWM (OR = 2.94; 95% CI: 1.34-6.43) groups. The combined administration of CHM and CWM substantially enhanced overall clinical effectiveness (OR = 3.44; 95% CI: 2.37-5.00). (b) VAS Score: CHM exhibited the capacity to diminish the VAS score in comparison to surgery alone (Mean difference (MD) = -0.86; 95% CI: -1.01 to -0.71). Nevertheless, no substantial advantage was observed compared to CWM alone (MD = -0.16; 95% CI: -0.49 to 0.17). The integration of CHM with CWM effectively ameliorated pain symptoms (MD = -0.87; 95% CI: -1.10 to -0.65). (c) Serum Level of Cancer antigen 125 (CA125): the CHM group potentially exhibited lower CA125 levels in comparison to CWM alone (MD = -11.08; 95% CI: -21.75 to -0.42). The combined intervention of CHM and CWM significantly decreased CA125 levels (MD = -5.31; 95% CI: -7.27 to -3.36). (d) Pregnancy Rate: CHM exhibited superiority in enhancing the pregnancy rate compared to surgery (OR = 3.95; 95% CI: 1.60-9.74) or CWM alone (OR = 3.31; 95% CI: 1.40-7.83). The combined utilization of CHM and CWM demonstrated the potential to enhance pregnancy rates compared to CWM (OR = 2.99; 95% CI: 1.28-6.98). Concerning safety outcome indicators, CHM effectively decreased the overall incidence of adverse events and, to a certain extent, alleviated perimenopausal symptoms as well as liver function impairment. (ⅲ) Most of CHMs were originated from classical Chinese herbal formulas. Prunus persica (L.) Batsch (Taoren), Angelica sinensis (Oliv.) Diels (Danggui), Salvia miltiorrhiza Bunge (Danshen), Paeonia lactiflora Pall. (Chishao), and Corydalis yanhusuo W.T.Wang (Yanhusuo) were most frequently used CHM.

Conclusion

CHM may be a viable choice in the long-term management of postoperative OEC, with the potential to enhance clinical efficacy while decreasing recurrence and adverse effects.

AURKA Enhances the Glycolysis and Development of Ovarian Endometriosis Through ERβ

Ovarian endometriosis (EMs) is a benign, estrogen-dependent gynecological disorder. Estrogen receptor beta (ERβ), a nuclear receptor for estradiol, plays an important role in the development of ovarian EMs. Here, we investigated the biological significance of aurora kinase A (AURKA) in ovarian EMs and the mechanism by which it regulates ERβ. We used immunohistochemical assays to verify that AURKA and ERβ were highly expressed in ectopic endometrial tissues. Cell proliferation and colony formation assays were used to demonstrate that AURKA promoted the proliferation of EMs cells. Wound-healing assay, Transwell migration assay, and Matrigel invasion assay further showed that AURKA enhanced the ability of EMs cells to migrate and invade. In addition, AURKA was shown to stimulate glycolysis in EMs cells by measuring the concentration of glucose and lactate in the cell supernatants. Moreover, the AURKA inhibitor alisertib was found to inhibit the progression of ovarian EMs and glycolysis in a mouse model of EMs by measuring ectopic tissues as well as by testing the peritoneal fluid of mice. Furthermore, coimmunoprecipitation assay showed that AURKA interacted with ERβ. The rescue experiments confirmed that AURKA regulated the development and glycolysis of ovarian EMs in an ERβ-dependent manner. AURKA contributed to the development of ovarian EMs by upregulating of ERβ. AURKA may represent a new target for the treatment of ovarian EMs.

CHIP induces ubiquitination and degradation of HMGB1 to regulate glycolysis in ovarian endometriosis

Ovarian endometriosis is a common gynecological condition that can cause infertility in women of childbearing age. However, the pathogenesis is still unknown. We demonstrate that the carboxyl terminus of Hsc70-interacting protein (CHIP) is a negative regulator in the development of endometriosis and reduces HMGB1 expression in endometriotic cells. Meanwhile, CHIP interacts with HMGB1 and promotes its ubiquitinated degradation, thereby inhibiting aerobic glycolysis and the progression of endometriosis. Furthermore, the CHIP agonist YL-109 effectively suppresses the growth of ectopic endometrium in endometriosis mouse model, which could be a potential therapeutic approach for endometriosis. In conclusion, our data suggest that CHIP may inhibit the development of endometriosis by suppressing the HMGB1-related glycolysis.

Cracking the enigma of adenomyosis: an update on its pathogenesis and pathophysiology

In brief

Traditionally viewed as enigmatic and elusive, adenomyosis is a fairly common gynecological disease but is under-recognized and under-researched. This review summarizes the latest development on the pathogenesis and pathophysiology of adenomyosis, which have important implications for imaging diagnosis of the disease and for the development of non-hormonal therapeutics.

Abstract

Traditionally considered as an enigmatic disease, adenomyosis is a uterine disease that affects many women of reproductive age and is a contributing factor for pelvic pain, heavy menstrual bleeding (HMB), and subfertility. In this review, the new development in the pathogenesis and pathophysiology of adenomyosis has been summarized, along with their clinical implications. After reviewing the progress in our understanding of the pathogenesis and describing the prevailing theories, in conjunction with their deficiencies, a new hypothesis, called endometrial-myometrial interface disruption (EMID), which is backed by extensive epidemiologic data and demonstrated by a mouse model, is reviewed, along with recent data implicating the role of Schwann cells in the EMI area in the genesis of adenomyosis. Additionally, the natural history of adenomyotic lesions is elaborated and underscores that, in essence, adenomyotic lesions are fundamentally wounds undergoing repeated tissue injury and repair (ReTIAR), which progress to fibrosis through epithelial-mesenchymal transition, fibroblast-to-myofibroblast transdifferentiation, and smooth muscle metaplasia. Increasing lesional fibrosis propagates into the neighboring EMI and endometrium. The increased endometrial fibrosis, with ensuing greater tissue stiffness, results in attenuated prostaglandin E2, hypoxia signaling and glycolysis, impairing endometrial repair and causing HMB. Compared with adenomyosis-associated HMB, the mechanisms underlying adenomyosis-associated pain are less understood but presumably involve increased uterine contractility, hyperinnervation, increased lesional production of pain mediators, and central sensitization. Viewed through the prism of ReTIAR, a new imaging technique can be used to diagnose adenomyosis more accurately and informatively and possibly help to choose the best treatment modality.

Impact of Chronic Exposure to Endometriosis on Perinatal Outcomes: Establishment of a Mouse Model

The purpose of this study was to establish a new mouse model of endometriosis that mimics real-world women’s health problems, in which women continue to be affected by endometriosis long before they wish to become pregnant, and to evaluate the impact of “chronic exposure to endometriosis” on perinatal outcome. Endometriosis was established by the intraperitoneal injection of homologous minced mouse uteri. Vehicle was injected for the control. Mating was initiated either 1 or 43 days after disease establishment (Young or Aged studies, respectively). Mice were sacrificed on 18 dpc. The number pups and resorptions were counted and pups’ body weights (BW) were measured, and the endometriosis lesion was identified and weighted. In the Young study, the number of resorptions and BW were comparable between the groups. In the Aged study, the number of resorptions was significantly higher and BW was significantly lower in endometriosis than that in control. The total weight of endometriosis lesion per dam was significantly lower in the Aged compared to the Young endometriosis group; however, not a single mouse was found to have any lesions at all. These results suggest that in addition to the presence of endometriosis per se, “chronic exposure to endometriosis” prior to pregnancy affect perinatal outcomes.

The Efficacy and Safety of the Zhuyun Formula and Auricular Acupressure for the Infertile Women with Recurrent Implantation Failure: A Randomized Controlled Trial

Background

Recurrent implantation failure (RIF), a clinical disorder characterized by failure to achieve pregnancy after repeated (≥3) embryo transfer, is a challenge for reproductive demands worldwide. In our preliminary work, the Zhuyun formula (ZYF) with auricular acupressure, a complementary and alternative medicine (CAM) with a small sample size for RIF, can improve the clinical pregnancy rate (41.2% vs. 26.7%, treatment group vs. control group, p < 0.05). Based on the toxicological and pregnancy-related pharmacological analysis of ZYF for RIF, the T-cell receptor signaling pathway might be involved in the pharmacological activity. This study aimed at evaluating the efficacy and safety of the CAM therapy according to pregnancy outcomes and maternal and child health and investigating the changes of T-helper (Th) cells in the peripheral blood of unexplained RIF women.

Materials and Methods

We conducted a prospective, two-arms, randomized, nonblinded study. All eligible women were randomly assigned to the treatment group (TG) and the control group (CG) according to a computer-generated randomization list in sealed opaque envelopes. Blood samples were collected from the two groups, and serum Th1, Th2, and Treg were detected by flow cytometry. The cytokines were detected by an enzyme-linked immunosorbent assay (ELISA). The TG was administrated with ZYF and auricular acupressure for three months before ovarian stimulation, while the control group was on a waiting list for the same period. The primary outcome was CPR. The second outcomes were the serum levels of immune parameters. For the safety evaluation, the perinatal outcomes of maternal and child were obtained by follow-up. Post-hoc sensitivity analyses were performed to assess the effect of missing data.

Results

One hundred and twenty-three women were randomized into the TG (n = 62) and CG (n = 61). The CPR was increased significantly in the TG (45.2%) than CG (26.2%) (p = 0.029). Twenty blood samples were collected, and the Th2/Th1 and Treg expression level was significantly higher in the TG than in the CG. IL-2, IL-10, and Foxp3 were higher significantly in the TG than in the CG. The maternal and child perinatal outcomes were not significantly different between the two groups.

Conclusions

The ZYF with auricular acupressure was effective and safe in improving the pregnancy outcomes of RIF. It might be related to balancing the level of cytokines related to the immune tolerance of the maternal-fetal interface to protect the embryo from the maternal immune system. Clinical Trial Registration: Clinical Trial Registry; date: 14/Dec/2013; no. NCT03078205.

A review of the effects of estrogen and epithelial-mesenchymal transformation on intrauterine adhesion and endometriosis

Uterus transplantation has become an option for women suffering from some form of infertility. Current review discusses key physiological functions of the endometrium requiring the transition of tissue cells between the mesenchyme and epithelial cell phenotype, a process known as epithelial-mesenchymal transition (EMT). Estrogen and EMT play a key role in the pathogenesis and treatment of intrauterine adhesion and endometriosis. There is also a close regulatory relationship between estrogen and EMT, and investigation of this relationship is of great significance for the treatment of endometrial disorders. The present review discusses the effects of estrogen on endometrial dysfunction, with a focus on the relationship between estrogen and EMT in endometrial disorders, taking into consideration the mechanisms by which receptors that regulate their functions and proteins that regulate their local biological functions interact with the factors involved in EMT. In addition, the review summarizes emerging drugs targeting receptors or proteins and provides information on the direction of new therapies for endometrial disorders.