Mitochondrial Dysfunction Induced by High Estradiol Concentrations in Endometrial Epithelial Cells

Connection Between HIV and Mitochondria in Cardiovascular Disease and Implications for Treatments

HIV infection and antiretroviral therapy alter mitochondrial function, which can progressively lead to mitochondrial damage and accelerated aging. The interaction between persistent HIV reservoirs and mitochondria may provide insight into the relatively high rates of cardiovascular disease and mortality in persons living with HIV. In this review, we explore the intricate relationship between HIV and mitochondrial function, highlighting the potential for novel therapeutic strategies in the context of cardiovascular diseases. We reflect on mitochondrial dynamics, mitochondrial DNA, and mitochondrial antiviral signaling protein in the context of HIV. Furthermore, we summarize how toxicities related to early antiretroviral therapy and current highly active antiretroviral therapy can contribute to mitochondrial dysregulation, chronic inflammation, and poor clinical outcomes. There is a need to understand the mechanisms and develop new targeted therapies. We further consider current and potential future therapies for HIV and their interplay with mitochondria. We reflect on the next-generation antiretroviral therapies and HIV cure due to the direct and indirect effects of HIV persistence, associated comorbidities, coinfections, and the advancement of interdisciplinary research fields. This includes exploring novel and creative approaches to target mitochondria for therapeutic intervention.

Gallic acid ameliorates endometrial hyperplasia through the inhibition of the PI3K/AKT pathway and the down-regulation of cyclin D1 expression

BACKGROUND

Gallic acid (GA) is an organic compound with phenolic properties that occurs naturally and can be found in Guizhi Fuling capsules, showcasing a wide range of biological functionalities.

PURPOSE

The objective of this study was to examine the influence of GA on endometrial hyperplasia (EH) and elucidate its underlying mechanism.

METHODS

Initially, the induction of EH was achieved by administering estradiol to mice via continuous subcutaneous injection for a duration of 21 days. Concurrently, GA treatment was administered, and subsequently, the uterine tissue structure was assessed using hematoxylin and eosin (H&E) staining. Following this, the proliferation of human endometrial cells treated by GA was determined utilizing the CCK-8 method. Furthermore, network pharmacology and single-cell-RNA-seq data were employed to identify the target of GA action. In addition, we will employ immunofluorescence (IF), immunohistochemistry (IHC), flow cytometry, western blot and RT-qPCR methodologies to investigate the impact of GA on the expression level of cyclin D1, PI3K, p-PI3K, AKT, p-AKT.

RESULTS

GA treatment ameliorated histopathological alterations in the uterus and suppress proliferation. Estradiol stimulation can activate the PI3K/AKT pathway, leading to up-regulation of cyclin D1 expression, whereas GA treatment results in down-regulation of its expression.

CONCLUSIONS

The expression of cyclin D1 is down-regulated by GA through the inhibition of the PI3K/AKT pathway, effectively mitigating estradiol-induced EH in mice.

Elevated estradiol levels on hCG trigger day adversely effects on the clinical pregnancy rates of blastocyst embryo transfer but not cleavage-stage embryo transfer in fresh cycles: a retrospective cohort study

Background

Elevated estradiol (E₂) levels are an inevitable outcome of the controlled ovulation hyperstimulation. However, the effect of this change on pregnancy is still uncertain. Our study aimed to analyze the impact of increased serum E₂ at the day of human chorionic gonadotropin (hCG) administration on the clinical outcomes of women with fresh embryo transfer (ET) cycles.

Methods

This study included 3,009 fresh ET cycles from October 2015 to September 2021. Based on the stage of embryos transferred, these cycles were categorized into the cleavage group and blastocyst group. Both groups were then divided into four sets according to E₂ levels when hCG was administered: set 1 (E₂ ≤ 2,000 pg/ml), set 2 (E₂ = 2,001-3,000 pg/ml), set 3 (E₂ = 3,001-4,000 pg/ml), and set 4 (E₂ > 4,000 pg/ml). The primary outcome was the clinical pregnancy rate (CPR). Binary logistics regression analysis was established to explore the association between CPR and E2 levels. Specifically, the threshold effect of serum E2 on CPR was revealed using the two-piecewise linear regression analyses.

Results

The multivariate regression model in the cleavage group showed that patients' CPR in set 4 was 1.59 times higher than those in reference set 1, but the statistical difference was insignificant (P = 0.294). As for the blastocyst group, patients in set 4 had a lower CPR with adjusted ORs of 0.43 (P = 0.039) compared to patients in set 1. The inflection point for the blastocyst group was 39.7 pg/dl according to the results of the two-piecewise linear regression model. When E₂ levels were over the point, the CPR decreased by 17% with every 1 pg/dl increases in serum E₂ (adjusted OR = 0.83, 95% CI [0.72-0.96], P = 0.012).

Conclusions

Elevated E₂ levels (>39.7 pg/dl) on hCG trigger day were associated with decreased CPR in patients with fresh blastocyst ET. However, it had no similar effect on the CPR of patients with fresh cleavage-stage ET.

Paeonol ameliorates endometrial hyperplasia in mice via inhibiting PI3K/AKT pathway-related ferroptosis

BACKGROUND

Paeonol (Pae) is one of the active ingredients from components of Guizhi Fuling Capsule, a traditional Chinese medicine widely used for the treatment of women's diseases, which exhibits various biological and pharmacological activities.

PURPOSE

The objective of this study was to investigate the molecular mechanism underlying the role of Pae in protecting against endometrial hyperplasia (EH).

METHODS

CCK-8 assay was performed to detect the effect of Pae on cell proliferation. Hematoxylin and eosin (H&E) staining was performed to evaluate uterine tissue structure. A network pharmacology study was performed to search the disease targets. Single-cell transcriptome analysis was performed with uterine tissues from 3 healthy donors and 3 EH patients on 10X Genomics platform. Changes in lipid peroxidation were detected by the MDA reaction. IHC assay, Western blot, immunofluorescence and RT-qPCR were used to study the effects of estradiol and Pae on the expression levels of GPX4, PI3K, AKT, p-PI3K, p-AKT in mice.

RESULTS

Pae treatment resulted in a decrease in cell viability of endometrial epithelial cells. Loss of uterus weight and morphology changes were observed in mice. In addition, Fe iron concentration and MDA levels increased, while the expression of GPX4, p-PI3K and p-AKT diminished.

CONCLUSIONS

Pae exhibited obvious alleviative activity in estradiol-induced mice via PI3K/AKT signaling pathway-regulated ferroptosis.

Exposure to iprodione induces ROS production and mitochondrial dysfunction in porcine trophectoderm and uterine luminal epithelial cells, leading to implantation defects during early pregnancy

Iprodione is a well-known fungicide used in the cultivation of strawberries, tomatoes, grapes, and green beans. In recent studies, neurotoxicity, cardiotoxicity, and endocrine toxicity of iprodione have been reported. Although reproductive toxicity of iprodione has been identified in animal studies, its effects are limited to male fertility. Also, the toxic effects of iprodione on pregnancy, especially the implantation process, have not been elucidated. This study demonstrated a series of cytotoxic responses of iprodione along with the alteration of implantation-related gene expression in porcine trophectoderm (pTr) and luminal epithelium (pLE) cells. In this study, iprodione suppressed cell viability, proliferation, and migration of these cells. Iprodione induced G1 phase arrest and attenuated spheroid formation by pTr and pLE cells. Furthermore, iprodione caused mitochondrial dysfunction and excessive reactive oxygen species generation, which resulted in an increase in mitochondrial calcium levels. Consequently, DNA damage and apoptotic cell death were induced by iprodione treatment in pTr and pLE cells. This stress-induced cell death was mediated by alterations in intracellular signal transduction, including the PI3K/AKT and MAPK signaling pathways. This finding suggests the potential of iprodione to impair the implantation capacity by exerting cytotoxic effects on fetal and maternal cells.

Gonadotropin Stimulation Reduces the Implantation and Live Birth Rate but Not the Miscarriage Rate of Embryos Transferred When Compared to Unstimulated In Vitro Fertilization

Research suggests that gonadotropin stimulation in in vitro fertilization (IVF) treatment affects embryo quality and the endometrium that might influence embryo implantation, placentation and establishment of a viable pregnancy. We assessed the impact of gonadotropin stimulation on implantation, live birth and miscarriage rates per transferred embryo by comparing stimulated and unstimulated IVF treatment. In a cohort of 728 couples, 1310 IVF cycles with successful embryo transfer were analysed; 857 cycles were stimulated with gonadotropins > 75 IU/day (333 poor responder < 4 oocytes; 524 normal responders), and 453 were unstimulated. In total, 1913 fresh cleavage-stage embryos were transferred. Zygote but no embryo selection was performed, and supernumerous zygotes were vitrified. The implantation rate was defined as number of sonographically detected amniotic sacs; live birth rate as number of children born per transferred embryo. Modified mixed effect Poisson regression was used to account for the dependency of cycles and embryos within the same women and the same transfer cycle. Adjustments were made for maternal age, parity, primary or secondary infertility and indication for IVF. Per transferred embryo, implantation rates (rate ratio (RR) 1.37; 95% CI 1.04-1.81; p = 0.028; aRR 1.42; 95% CI 1.10-1.84; p = 0.008) and live birth rates (RR 1.33; 95% CI 0.95-1.86; p = 0.093; aRR 1.38; 95% CI 1.01-1.88; p = 0.044) were higher in NC-IVF compared to cIVF normal responders. Miscarriage did not differ (RR 0.99; 95% CI 0.59-1.65; p = 0.965; aRR 0.90; 95% CI 0.52-1.53 p = 0.698). Similar results were obtained in poor responders. The study suggests an impact of gonadotropin stimulation on the implantation potential of embryos.

Silibinin improves L-cell mass and function through an estrogen receptor-mediated antioxidative mechanism

BACKGROUND

Silibinin, a major component of milk thistle extract silymarin, promotes hypoglycemia by activating estrogen receptor (ER) α and β-mediated pathways in pancreatic β-cells. Glucagon-like peptide-1 (GLP-1) is the enteroendocrine peptide produced in L-cells, and it controls glucose homeostasis through multiple pathways. The effect of silibinin on L-cell mass and function is still unknown.

PURPOSE

The protective effect of silibinin on palmitate (PA)-treated intestinal L-cell line GLUTag cells and the SHRSP•Z-Leprfa/Izm-Dmcr (SP•ZF) diabetic rat model was investigated in current study.

METHODS

After pre-incubation with 50 μM silibinin for 4 h, GLUTag cells were treated with 0.125 mM PA. MTT, Annexin V/PI apoptosis, Hoechst 33342 staining, western blot, DCFH-DA, GLP-1 ELISA, qRT-PCR and immunofluorescence analyses were undertaken to determine ER-dependent protection of silibinin against PA-induced cellular damage. The differential protein expression of GLUTag cells under different treatments was examined by matrix-assisted laser desorption/ionization time-of-flight (MALDI-TOF) mass spectrometry (MS). The SP•ZF diabetic rat model was chosen for in vivo study. After 4 weeks of gastric gavage with 100 or 300 mg kg-1 of silibinin, the physiological indexes of the rats were measured. Cells expressing GLP-1, 8‑hydroxy-2'-deoxyguanosine (8-OHdG), ERα, and/or ERβ in duodenum tissues were detected by immunofluorescence.

RESULTS

The current study showed that the GLUTag cells preincubated with silibinin activated the transcription factor nuclear erythroid-2 like factor-2 (Nrf2)-antioxidant pathway, reduced reactive oxygen species (ROS) generation, and improved cell survival and GLP-1 content, while the antioxidative effect of silibinin was blocked by the selective ERα antagonist MPP or ERβ antagonist PHTPP in GLUTag cells. Our proteomics data further revealed that ERα or β inactivation reduced glutathione peroxide and proteins associated with endocytosis and reproduction, thus at least partially reversing the protective effect of silibinin. SP•ZF rats received silibinin treatment showed increased serum GLP-1 content and improved glucose homeostasis. Furthermore, silibinin upregulated ERα and β levels and reduced the level of 8-OHdG in GLP-1-positive cells.

CONCLUSIONS

Our study showed that silibinin improved L-cell mass and function through an ER-mediated antioxidant pathway, and the proteomics analysis revealed for the first time the differential regulation of proteins by PA and silibinin in GLUTag cells.

Impact of superovulation and in vitro fertilization on LINE-1 copy number and telomere length in C57BL/6 J mice blastocysts

OBJECTIVE

Millions of babies have been conceived by IVF, yet debate about its safety to offspring continues. We hypothesized that superovulation and in vitro fertilization (IVF) promote genomic changes, including altered telomere length (TL) and activation of the retrotransposon LINE-1 (L1), and tested this hypothesis in a mouse model.

MATERIAL AND METHODS

Experimental study analyzing TL and L1 copy number in C57BL/6 J mouse blastocysts in vivo produced from natural mating cycles (N), in vivo produced following superovulation (S), or in vitro produced following superovulation (IVF). We also examined the effects of prolonged culture on TL and L1 copy number in the IVF group comparing blastocysts cultured 96 h versus blastocysts cultured 120 h. TL and L1 copy number were measured by Real Time PCR.

RESULTS

TL in S (n = 77; Mean: 1.50 ± 1.15; p = 0.0007) and IVF (n = 82; Mean: 1.72 ± 1.44; p < 0.0001) exceeded that in N (n = 16; Mean: 0.61 ± 0.27). TL of blastocysts cultured 120 h (n = 15, Mean: 2.14 ± 1.05) was significantly longer than that of embryos cultured for 96 h (n = 67, Mean: 1.63 ± 1.50; p = 0.0414). L1 copy number of blastocysts cultured for 120 h (n = 15, Mean: 1.71 ± 1.49) exceeded that of embryos cultured for 96 h (n = 67, Mean: 0.95 ± 1.03; p = 0.0162).

CONCLUSIONS

Intriguingly ovarian stimulation, alone or followed by IVF, produced embryos with significantly longer telomeres compared to in vivo, natural cycle-produced embryos. The significance of this enriched telomere endowment for the health and longevity of offspring born from IVF merit future studies.

The Association Between Serum Estradiol Levels on hCG Trigger Day and Live Birth Rates in Non-PCOS Patients: A Retrospective Cohort Study

OBJECTIVE

To retrospectively analyze the association of serum estradiol (E2) levels on human chorionic gonadotropin (hCG) trigger day and live birth rates (LBRs) in women undergoing fresh embryo transfer and not exhibiting polycystic ovary syndrome.

DESIGN

Retrospective cohort study.

METHODS

Analysis of 13,950 patients who had fresh embryo transfer between December 2013 and December 2019. The main outcome measurement was LBRs. Multivariable regression analysis was performed to investigate associations between E2 levels on the hCG trigger day and LBRs. Stratification analysis was performed to test for effect modification in subgroups. Furthermore, a two-piecewise linear regression model was established to find nonlinear relationships.

RESULTS

Multivariable regression analysis showed a significant association between serum E2 levels on the hCG trigger day and LBRs, adjusting for covariates [relative risk (RR) 1.027, 95% confidence interval (CI) 1.007, 1.049]. Stratification analysis showed that the LBRs were positively associated (RR 1.052, 95% CI 1.004, 1.102) with every 1 ng/ml increase of serum E2 on the hCG trigger day for the subgroup with low antral follicle counts on the trigger day. Specifically, a two-piecewise linear regression model showed that there was a positive association (RR 1.188, 95% CI 1.057, 1.334) between serum E2 and LBR for every increase of 1 ng/ml E2 when the concentration of serum E2 was lower than 2.1 ng/ml. However, there was no significant association (RR 1.002, 95% CI 0.971, 1.032) between E2 levels and LBRs when the concentration of E2 was higher than the 2.1ng/ml inflection point.

CONCLUSIONS

Serum E2 levels on the hCG trigger day were segmentally connected with LBRs.

Intentional endometrial injury enhances angiogenesis through increased production and activation of MMP-9 by TNF-α and MMP-3 in a mouse model

There have been reports of improved pregnancy rates after performing intentional endometrial injuries, also known as endometrial scratching, in patients with recurrent implantation failure. In our previous study on intentional endometrial injury, we found an increased expression of matrix metalloproteinase (MMP)-3 following induced injuries to the mice endometrium. In the current study, we further examine whether the rise in MMP-3 could contribute to increased angiogenesis. Female C57B1/6 mice were obtained at 12 weeks of age, and intentional endometrial injuries were induced mechanically in the left uterine horns. Using the appropriate media, uterine-washes were performed on the injured and uninjured (control) horns of the harvested uteri. The uterine tissues were further processed for tissue lysates, histopathology and immunohistochemistry. The results show that intentional endometrial injuries caused an increase in secreted LPA in the injured horns, which were detected in the uterine-washes. In addition, LPA induced increased production of TNF-α in human endometrial epithelial cells (hEEpCs). Furthermore, TNF-α appeared to induce differential and cell-specific upregulation of the MMPs: MMP-3 was upregulated in the epithelial (hEEpCs), while MMP-9 was upregulated in the endothelial cells (human endometrial endothelial cells; hEEnCs). The upregulation of MMP-3 appeared to be necessary for the activation of MMP-9, whose active form stimulated the formation of vessel-like structure by the hEEnCs. The results of this study suggest that there may be enhanced angiogenesis following intentional endometrial injuries, which is mediated in part by TNF-α-induced and MMP-3-activated MMP-9 production.

Endometrial function in women with polycystic ovary syndrome: a comprehensive review

BACKGROUND

Polycystic ovary syndrome (PCOS) is the most common cause of anovulatory infertility. An endometrial component has been suggested to contribute to subfertility and poor reproductive outcomes in affected women.

OBJECTIVE AND RATIONALE

The aim of this review was to determine whether there is sufficient evidence to support that endometrial function is altered in women with PCOS, whether clinical features of PCOS affect the endometrium, and whether there are evidence-based interventions to improve endometrial dysfunction in PCOS women.

SEARCH METHODS

An extensive literature search was performed from 1970 up to July 2020 using PubMed and Web of Science without language restriction. The search included all titles and abstracts assessing a relationship between PCOS and endometrial function, the role played by clinical and biochemical/hormonal factors related to PCOS and endometrial function, and the potential interventions aimed to improve endometrial function in women with PCOS. All published papers were included if considered relevant. Studies having a specific topic/hypothesis regarding endometrial cancer/hyperplasia in women with PCOS were excluded from the analysis.

OUTCOMES

Experimental and clinical data suggest that the endometrium differs in women with PCOS when compared to healthy controls. Clinical characteristics related to the syndrome, alone and/or in combination, may contribute to dysregulation of endometrial expression of sex hormone receptors and co-receptors, increase endometrial insulin-resistance with impaired glucose transport and utilization, and result in chronic low-grade inflammation, immune dysfunction, altered uterine vascularity, abnormal endometrial gene expression and cellular abnormalities in women with PCOS. Among several interventions to improve endometrial function in women with PCOS, to date, only lifestyle modification, metformin and bariatric surgery have the highest scientific evidence for clinical benefit.

WIDER IMPLICATIONS

Endometrial dysfunction and abnormal trophoblast invasion and placentation in PCOS women can predispose to miscarriage and pregnancy complications. Thus, patients and their health care providers should advise about these risks. Although currently no intervention can be universally recommended to reverse endometrial dysfunction in PCOS women, lifestyle modifications and metformin may improve underlying endometrial dysfunction and pregnancy outcomes in obese and/or insulin resistant patients. Bariatric surgery has shown its efficacy in severely obese PCOS patients, but a careful evaluation of the benefit/risk ratio is warranted. Large scale randomized controlled clinical trials should address these possibilities.

Role of 17β-Estradiol on Cell Proliferation and Mitochondrial Fitness in Glioblastoma Cells

Gliomas are the most common primary tumors of the central nervous system (CNS) in the adult. Previous data showed that estrogen affects cancer cells, but its effect is cell-type-dependent and controversial. The present study aimed to analyze the effects of estradiol (E2, 5 nM) in human glioblastoma multiforme U87-MG cells and how it may impact on cell proliferation and mitochondrial fitness. We monitored cell proliferation by xCELLigence technology and mitochondrial fitness by assessing the expression of genes involved in mitochondrial biogenesis (PGC1α, SIRT1, and TFAM), oxidative phosphorylation (ND4, Cytb, COX-II, COX IV, NDUFA6, and ATP synthase), and dynamics (OPA1, MNF2, MNF1, and FIS1). Finally, we evaluated Nrf2 nuclear translocation by immunocytochemical analysis. Our results showed that E2 resulted in a significant increase in cell proliferation, with a significant increase in the expression of genes involved in various mechanisms of mitochondrial fitness. Finally, E2 treatment resulted in a significant increase of Nrf2 nuclear translocation with a significant increase in the expression of one of its target genes (i.e., heme oxygenase-1). Our results suggest that E2 promotes proliferation in glioblastoma cells and regulate the expression of genes involved in mitochondrial fitness and chemoresistance pathway.

High Dosages of Equine Chorionic Gonadotropin Exert Adverse Effects on the Developmental Competence of IVF-Derived Mouse Embryos and Cause Oxidative Stress-Induced Aneuploidy

Gonadotropins play vital roles in the regulation of female reproductive ability and fertility. Our study aimed to determine the effects of superovulation induced by increasing doses of equine chorionic gonadotropin [eCG; also referred to as pregnant mare serum gonadotropin (PMSG)] on the developmental competence of mouse embryos and on aneuploidy formation during in vitro fertilization (IVF). eCG dose-dependently enhanced the oocyte yield from each mouse. Administration of 15 IU eCG significantly reduced the fertilization rate and the formation of four-cell embryos and blastocysts and increased the risk of chromosome aneuploidy. The IVF-derived blastocysts in the 15 IU eCG treatment group had the fewest total cells, inner cell mass (ICM) cells and trophectoderm (TE) cells. Moreover, more blastocysts and fewer apoptotic cells were observed in the 0, 5, and 10 IU eCG treatment groups than in the 15 IU eCG treatment group. We also investigated reactive oxygen species (ROS) levels and variations in several variables: mitochondrial membrane potential (MMP); active mitochondria; mitochondrial superoxide production; adenosine triphosphate (ATP) content; spindle structures; chromosome karyotypes; microfilament distribution; and the expression of Aurora B [an important component of the chromosomal passenger complex (CPC)], the spindle assembly checkpoint (SAC) protein mitotic arrest deficient 2 like 1 (MAD2L1), and the DNA damage response (DDR) protein γH2AX. Injection of 15 IU eCG increased ROS levels, rapidly reduced MMP, increased active mitochondria numbers and mitochondrial superoxide production, reduced ATP content, increased abnormal spindle formation rates, and induced abnormalities in chromosome number and microfilament distribution, suggesting that a high dose of eCG might alter developmental competence and exert negative effects on IVF-obtained mouse embryos. Additionally, the appearance of γH2AX and the significantly increased expression of Aurora B and MAD2L1 suggested that administration of relatively high doses of eCG caused Aurora B-mediated SAC activation triggered by ROS-induced DNA damage in early mouse IVF-derived embryos for self-correction of aneuploidy formation. These findings improve our understanding of the application of gonadotropins and provide a theoretical basis for gonadotropin treatment.