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-ß1, 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.

New insights on mitochondrial heteroplasmy observed in ovarian diseases.

BACKGROUND: The reportedly high mutation rate of mitochondrial DNA (mtDNA) may be attributed to the absence of histone protection and complete repair mechanisms. Mitochondrial heteroplasmy refers to the coexistence of wild-type and mutant mtDNA. Most healthy individuals carry a low point mutation load (<1 %) in their mtDNA, typically without any discernible phenotypic effects. However, as it exceeds a certain threshold, it may cause the onset of various diseases. Since the ovary is a highly energy-intensive organ, it relies heavily on mitochondrial function. Mitochondrial heteroplasmy can potentially contribute to a variety of significant ovarian disorders. AIM OF REVIEW: In this review, we have elucidated the close relationship between mtDNA heteroplasmy and ovarian diseases, and summarized novel avenues and strategies for the potential treatment of these ovarian diseases. KEY SCIENTIFIC CONCEPTS OF REVIEW: Mitochondrial heteroplasmy can potentially contribute to a variety of significant ovarian disorders, including polycystic ovary syndrome, premature ovarian insufficiency, and endometriosis. Current strategies related to mitochondrial heteroplasmy are untargeted and have low bioavailability. Nanoparticle delivery systems loaded with mitochondrial modulators, mitochondrial replacement/transplantation therapy, and mitochondria-targeted gene editing therapy may offer promising paths towards potentially more effective treatments for these diseases, despite ongoing challenges.

Risk factors for coexisting deep endometriosis for patients with recurrent ovarian endometrioma.

Aim: The aim of this study was to assess the risk factors for coexisting deep endometriosis (DE) in patients with recurrent ovarian endometrioma (OE). Methods: We retrospectively reviewed 151 recurrent OE patients who had been diagnosed of OE but not DE at the time of their first surgery and then received a second surgery for recurrent endometriosis with or without DE. Their clinical characteristics at the time of the first and second surgeries were collected. Univariate and multivariate logistic regression analyses were conducted to identify potential risk factors for coexisting DE in patients with recurrent OE. Results: Among the 151 recurrent OE patients, 46 were diagnosed of DE during the recurrent surgery and included in the DE group, while the remaining 105 patients were included in the non-DE group. In univariate analysis, there were significant differences in terms of uterine retroversion during the primary surgery and the follow-up time after the primary surgery between the DE and non-DE groups. The multivariate analysis also showed that both uterine retroversion and the follow-up time (≥5 years) were associated with the coexistence of DE during the recurrent surgery. The odds ratio (OR) for uterine retroversion was 3.72 [95% confidence interval (CI) 1.62-8.53], and the OR for follow-up time (≥5 years) was 5.03 (95% CI 2.29-11.02). Conclusions: Our study suggested that for recurrent OE patients, uterine retroversion during the first surgery and a follow-up time of at least 5 years are risk factors for the coexistence of DE in recurrent surgery, early prevention and full preparation before the recurrent surgery should be emphasized in these conditions.

Glia Maturation Factor Beta as a Novel Biomarker and Therapeutic Target for Hepatocellular Carcinoma.

Hepatocellular carcinoma (HCC) is one of the most common types of cancer. The novel sensitive biomarkers and therapeutic targets are urgently needed for the early diagnosis of HCC and improvement of clinical outcomes. Glia maturation factor-ß (GMFB) is a growth and differentiation factor for both glia and neurons and has been found to be tightly involved in inflammation and neurodegeneration conditions. In our study, the expression level of GMFB was significantly up-regulated in patients with HCC and positively co-expression with tumor node metastases (TNM) stage and histopathological grade of HCC. The high expression level of GMFB was remarkably associated with poor overall survival, which mainly occurred in males rather than females. Multivariate analysis revealed GMFB to be an independent prognostic factor for overall survival in patients with HCC. Results of Gene Ontology (GO) and KEGG pathways analysis showed that down-regulation of pathways related to protein translation and mitochondria function were enriched. Protein-protein interaction analysis revealed the central role of mitochondria protein in HCC. The downregulation of genes involved in glycolysis and gluconeogenesis was observed among the co-expression genes of GMFB. Knockdown of GMFB in Hep3B significantly inhibited proliferation, migration, and invasion of Hep3B cells, and also downregulated the expression levels of some of metal matrix proteinase (MMP), increased mtDNA copy number and loss of mitochondrial transmembrane potential. GMFB influences the malignancy rate of HCC possibly through regulation of the expression of MMPs, mtDNA function and glycolysis. We proposed that GMFB was a promising HCC diagnostic and prognostic biomarker and therapeutic target in HCC.

Perspective on prenatal polychlorinated biphenyl exposure and the development of the progeny nervous system (Review).

The developmental origins of health and disease concept illustrates that exposure in early life to various factors may affect the offspring's long­term susceptibility to disease. During development, the nervous system is sensitive and vulnerable to the environmental insults. Polychlorinated biphenyls (PCBs), which are divided into dioxin­like (DL­PCBs) and non­dioxin­like PCBs (NDL­PCBs), are synthetic persistent environmental endocrine­disrupting chemicals. The toxicological mechanisms of DL­PCBs have been associated with the activation of the aryl hydrocarbon receptor and NDL­PCBs have been associated with ryanodine receptor­mediated calcium ion channels, which affect neuronal migration, promote dendritic growth and alter neuronal connectivity. In addition, PCB accumulation in the placenta destroys the fetal placental unit and affects endocrine function, particularly thyroid hormones and the dopaminergic system, leading to neuroendocrine disorders. However, epidemiological investigations have not achieved a consistent result in different study cohorts. The present review summarizes the epidemiological differences and possible mechanisms of the effects of intrauterine PCB exposure on neurological development.

Mitochondria and oxidative stress in ovarian endometriosis.

Endometriosis is associated with inflammatory reaction, and reactive oxidative species (ROS) are highly pro-inflammatory factors. Mitochondria are responsible for the production of ROS and energy. However, little is known about how mitochondria regulate ROS generation and energy metabolism in endometriosis. In our study, we investigated mitochondrial structure and function of ectopic endometrial stromal cells (ESCs) in ovarian endometriosis. We found mitochondria in ectopic ESCs generated more ROS and energy than controlled groups. Mitochondrial superoxide dismutase (SOD2), as an antioxidant enzyme, was found highly expressed in ectopic endometrium compared with normal endometrium. Due to its antioxidant role, SOD2 promoted the development of endometriosis by maintaining functional mitochondria to support high energetic metabolism of ectopic ESCs. We also showed that SOD2 promoted cell proliferation and migration in ovarian endometriosis. Inhibiting SOD2 expression reduced proliferation and migration of ectopic ESCS, and increased cell apoptosis. Therefore, understanding the role of mitochondrial dysfunction and SOD2 in ovarian endometriosis may provide new strategies to treat this disease.

Extrauterine epithelioid trophoblastic tumors presenting as lung mass: A case report and literature review.

RATIONALE: Extrauterine epithelioid trophoblastic tumors (ETT) is a rare variant of gestational trophoblastic neoplasms. Here we aim to learn more clinical and pathological characteristics of ETT patient with an isolated pulmonary mass without uterine lesions, through a rare case of extra-uterine ETT and 7 cases published in English periodicals literature. PATIENT CONCERNS: A 31-year-old Chinese woman, presented with low-level elevation of serum human chorionic gonadotropin (HCG) for more than 2 years without abnormal symptoms. Dilation and curettage (D&C) was performed and histopathology revealed a secretory phase of endometrium. Chest computed tomography (CT) scan showed a 0.8 cm nodular lesion in the upper left lobe. Then a thoracotomy with left upper lobe segmentectomy was performed. DIAGNOSIS: After pathological and immunohistochemistry diagnosis, the case was confirmed as ETT (III). INTERVENTIONS: According to FIGO guideline, the patient took 3 cycles of multivalent chemotherapy consisting of cisplatin and etoposide, alternating with etoposid, methotrexate dactinomycin (EP-EMA). OUTCOMES: The patient had no obvious signs of recurrence after 13 months of follow-up. LESSONS: When a fertile age woman persistently shows abnormal low-level escalation of HCG, ETT should be taken into consideration, especially lung X-ray or CT showing lesions without apparent abnormality of the uterus.

Prophylactic uterine artery embolization in second-trimester pregnancy termination with complete placenta previa.

OBJECTIVE: This study was performed to assess whether prophylactic uterine artery embolization (UAE) is beneficial for second-trimester abortion with complete placenta previa (CPP). METHODS: Patients with CPP who underwent second-trimester pregnancy termination by labor induction with or without UAE from January 2010 to January 2018 were retrospectively reviewed. In total, 25 patients were eligible for analysis. The primary outcomes were the abortion success rate and bleeding volume, and the secondary outcomes were the induction-to-abortion time, length of hospital stay, and complications. RESULTS: CPP occurred in all 25 patients. Fifteen patients underwent prophylactic UAE (UAE group) and 10 did not (control group). Abortion was successful in 13 of 15 (86.7%) women in the UAE group and in 9 of 10 (90.0%) women in the control group. There was no significant difference in the bleeding volume or induction-to-abortion time between the two groups. The hospital stay was longer and pyrexia was more common in the UAE than control group. CONCLUSION: Prophylactic UAE did not markedly improve the outcomes of second-trimester abortion in patients with CPP. Conversely, it may increase the risk of complications and prolong the hospital stay.

High levels of GSK-3ß signalling reduce osteogenic differentiation of stem cells in osteonecrosis of femoral head.

Osteonecrosis of the femoral head (ONFH) is a common but intractable disease. In this study, we investigated the mechanisms regulating alterations in mesenchymal stem cell (MSC) differentiation in ONFH. Five patients who were diagnosed with ONFH were enrolled in this study. Bone MSCs (BMSCs) were isolated from the osteonecrotic zone in the femoral head (FH-pMSCs) and from the normal zone in the pelvis (hMSCs) of the same patient. Morphology, cell proliferation and expression of mediators of the Wnt signalling pathway were evaluated. There were significant differences in cell proliferation and expression of surface markers between the two populations of cells. FH-pMSCs exhibited significantly lower osteogenic differentiation compared with hMSCs (P < 0.0001). Dissection of the Wnt pathway showed that FH-pMSCs had significantly higher GSK3ß expression compared with hMSCs (P < 0.001). Addition of LiCl, a GSK3ß inhibitor, significantly increased osteogenic differentiation in FH-pMSCs, suggesting a relationship between the microenvironment and regulation of stem cell behaviour in ONFH. FH-pMSCs also exhibited significant downregulation of other mediators of the Wnt signalling pathway, including runx2 and ß-catenin. Our data suggested that mediators of the Wnt signalling pathway, such as GSK3ß could be important therapeutic targets for early-stage ONFH.

Polychlorinated biphenyls and its potential role in endometriosis.

With the progress of global industrialization and environmental deterioration, the relationship between human health and the living environment has become an increasing focus of attention. Polychlorinated biphenyls (PCBs, including dioxin-like polychlorinated biphenyls and non-dioxin-like polychlorinated biphenyls), as part of the organic chlorine contaminants, have been suspected as playing a role in the etiopathogenesis of endometriosis. Several population-based studies have proposed that exposure to PCBs may increase the risk of developing endometriosis, while some epidemiological studies have failed to find any association between PCBs and endometriosis. The purpose of this review is to discuss the potential pathophysiological relationship between endometriosis and PCBs with a focus on both dioxin-like polychlorinated biphenyls and non-dioxin-like polychlorinated biphenyls.

Role of Interleukin-6 and Its Receptor in Endometriosis.

BACKGROUND Studies have shown that the concentration of interleukin (IL)-6 in peritoneal fluid is increased in patients with endometriosis; however, whether the disorders involving IL-6 contribute to the development of endometriosis is still unclear. In the present study, we evaluated the potential role of IL-6 and IL-6 receptor (IL-6R) in the pathogenesis of endometriosis. MATERIAL AND METHODS We examined activated macrophages and the expression of membrane-binding receptor (mIL-6R) in peritoneal fluid using flow cytometry. The levels of IL-6 and the IL-6 soluble receptor (sIL-6R) in peritoneal fluid and plasma in patients with endometriosis was measured by an enzyme-linked immunosorbent assay. RESULTS Activated macrophages and mIL-6R in peritoneal fluid were increased in patients with endometriosis. IL-6 and sIL-6R in peritoneal fluid were also increased in patients with endometriosis; however, there was an increase in plasma IL-6 and a decrease in plasma sIL-6R. The endometriosis group was categorized into 2 groups according to the retrospective American Fertility Society Score (r-AFS): group A and group B. Peritoneal fluid sIL-6R in endometriosis group B was significantly higher than in endometriosis group A and the control group. CONCLUSIONS Disorders involving IL-6 and IL-6R are correlated with the etiology of endometriosis. An increase in sIL-6R in peritoneal fluid promotes the development of endometriosis by enhancing the bioactivity of IL-6.

Human Cartilage-Derived Progenitor Cells From Committed Chondrocytes for Efficient Cartilage Repair and Regeneration.

UNLABELLED: Articular cartilage is not a physiologically self-renewing tissue. Injury of cartilage often progresses from the articular surface to the subchondral bone, leading to pathogenesis of tissue degenerative diseases, such as osteoarthritis. Therapies to treat cartilage defects using autologous chondrocyte-based tissue engineering have been developed and used for more than 20 years; however, the challenge of chondrocyte expansion in vitro remains. A promising cell source, cartilage stem/progenitor cells (CSPCs), has attracted recent attention. Because their origin and identity are still unclear, the application potential of CSPCs is under active investigation. Here we have captured the emergence of a group of stem/progenitor cells derived from adult human chondrocytes, highlighted by dynamic changes in expression of the mature chondrocyte marker, COL2, and mesenchymal stromal/stem cell (MSC) marker, CD146. These cells are termed chondrocyte-derived progenitor cells (CDPCs). The stem cell-like potency and differentiation status of CDPCs were determined by physical and biochemical cues during culture. A low-density, low-glucose 2-dimensional culture condition (2DLL) was critical for the emergence and proliferation enhancement of CDPCs. CDPCs showed similar phenotype as bone marrow mesenchymal stromal/stem cells but exhibited greater chondrogenic potential. Moreover, the 2DLL-cultured CDPCs proved efficient in cartilage formation both in vitro and in vivo and in repairing large knee cartilage defects (6-13 cm(2)) in 15 patients. These findings suggest a phenotype conversion between chondrocytes and CDPCs and provide conditions that promote the conversion. These insights expand our understanding of cartilage biology and may enhance the success of chondrocyte-based therapies. SIGNIFICANCE: Injury of cartilage, a non-self-repairing tissue, often progresses to pathogenesis of degenerative joint diseases, such as osteoarthritis. Although tissue-derived stem cells have been shown to contribute to tissue renewal and homeostasis, the derivation, biological function, and application potential of stem/progenitor cells found in adult human articular cartilage are incompletely understood. This study reports the derivation of a population of cartilage stem/progenitor cells from fully differentiated chondrocytes under specific culture conditions, which have the potential to reassume their chondrocytic phenotype for efficient cartilage regeneration. These findings support the possibility of using in vitro amplified chondrocyte-derived progenitor cells for joint cartilage repair.

Cartilage stem/progenitor cells are activated in osteoarthritis via interleukin-1ß/nerve growth factor signaling.

INTRODUCTION: Interleukin-1ß (IL-1ß) and nerve growth factor (NGF) are key regulators in the pathogenesis of inflammatory arthritis; specifically, IL-1ß is involved in tissue degeneration and NGF is involved in joint pain. However, the cellular and molecular interactions between IL-1ß and NGF in articular cartilage are not known. Cartilage stem/progenitor cells (CSPCs) have recently been identified in osteoarthritic (OA) cartilage on the basis of their migratory properties. Here we hypothesize that IL-1ß/NGF signaling is involved in OA cartilage degeneration by targeting CSPCs. METHOD: NGF and NGF receptor (NGFR: TrkA and p75NTR) expression in healthy and OA human articular cartilage and isolated chondrocytes was determined by immunostaining, qRT-PCR, flow cytometry and western blot. Articular cartilage derived stem/progenitor cells were collected and identified by stem/progenitor cell characteristics. 3D-cultured CSPC pellets and cartilage explants were treated with NGF and NGF neutralizing antibody, and extracellular matrix changes were examined by sulfated glycosaminoglycan (GAG) release and MMP expression and activity. RESULTS: Expression of NGF, TrkA and p75NTR was found to be elevated in human OA cartilage. Cellular changes upon IL-1ß and/or NGF treatment were then examined. NGF mRNA and NGFR proteins levels were upregulated in cultured chondrocytes exposed to IL-1ß. NGF was chemotactic for cells isolated from OA cartilage. Cells isolated on the basis of their chemotactic migration towards NGF demonstrated stem/progenitor cell characteristics, including colony-forming ability, multi-lineage differentiation potential, and stem cell surface markers. The effects of NGF perturbation in cartilage explants and 3D-cultured CSPCs were next analyzed. NGF treatment resulted in extracellular matrix catabolism indicated by increased sGAG release and MMP expression and activity; conversely, treatment with NGF neutralizing antibody inhibited increased MMP levels, and enhanced tissue inhibitor of matrix metalloprotease-1 (TIMP1) expression in OA cartilage explants. NGF blockade with neutralizing antibody also affected cartilage matrix remodeling in 3D-CSPC pellet cultures. CONCLUSION: Our results strongly suggest that NGF signaling is a contributing factor in articular cartilage degeneration in OA, which likely targets a specific subpopulation of progenitor cells, the CSPCs, affecting their migratory and matrix remodeling activities. These findings provide novel cellular/signaling therapeutic targets in osteoarthritic cartilage.

The promotion of osteochondral repair by combined intra-articular injection of parathyroid hormone-related protein and implantation of a bi-layer collagen-silk scaffold.

The repair of osteochondral defects can be enhanced with scaffolds but is often accompanied with undesirable terminal differentiation of bone marrow-derived mesenchymal stem cells (BMSCs). Parathyroid hormone-related protein (PTHrP) has been shown to inhibit aberrant differentiation, but administration at inappropriate time points would have adverse effects on chondrogenesis. This study aims to develop an effective tissue engineering strategy by combining PTHrP and collagen-silk scaffold for osteochondral defect repair. The underlying mechanisms of the synergistic effect of combining PTHrP administration with collagen-silk scaffold implantation for rabbit knee joint osteochondral defect repair were investigated. In vitro studies showed that PTHrP treatment significantly reduced Alizarin Red staining and expression of terminal differentiation-related markers. This is achieved in part through blocking activation of the canonical Wnt/ß-catenin signaling pathway. For the in vivo repair study, intra-articular injection of PTHrP was carried out at three different time windows (4-6, 7-9 and 10-12 weeks) together with implantation of a bi-layer collagen-silk scaffold. Defects treated with PTHrP at the 4-6 weeks time window exhibited better regeneration (reconstitution of cartilage and subchondral bone) with minimal terminal differentiation (hypertrophy, ossification and matrix degradation), as well as enhanced chondrogenesis (cell shape, Col2 and GAG accumulation) compared with treatment at other time windows. Furthermore, the timing of PTHrP administration also influenced PTHrP receptor expression, thus affecting the treatment outcome. Our results demonstrated that intra-articular injection of PTHrP at 4-6 weeks post-injury together with collagen-silk scaffold implantation is an effective strategy for inhibiting terminal differentiation and enhancing chondrogenesis, thus improving cartilage repair and regeneration in a rabbit model.

The use of type 1 collagen scaffold containing stromal cell-derived factor-1 to create a matrix environment conducive to partial-thickness cartilage defects repair.

Despite the presence of cartilage-derived mesenchymal stem cells (C-MSCs) and synovial membrane-derived mesenchymal stem cells (SM-MSCs) populations, partial-thickness cartilage defects, in contrast to the full-thickness defects, are devoid of spontaneous repair capacity. This study aims to create an in situ matrix environment conducive to C-MSCs and SM-MSCs to promote cartilage self-repair. Spontaneous repair with MSCs migration into the defect area was observed in full-thickness defects, but not in partial-thickness defects in rabbit model. Ex vivo and in vitro studies showed that subchondral bone or type 1 collagen (col1) scaffold was more permissive for MSCs adhesion than cartilage or type 2 collagen (col2) scaffold and induced robust stromal cell-derived factors-1 (SDF-1) dependent migration of MSCs. Furthermore, creating a matrix environment with col1 scaffold containing SDF-1 enhanced in situ self-repair of partial-thickness defects in rabbit 6 weeks post-injury. Hence, the inferior self-repair capacity in partial-thickness defects is partially owing to the non-permissive matrix environment. Creating an in situ matrix environment conducive to C-MSCs and SM-MSCs migration and adhesion with col1 scaffold containing SDF-1 can be exploited to improve self-repair capacity of cartilage.