Iron overload in endometriosis peritoneal fluid induces early embryo ferroptosis mediated by HMOX1

AbstractEndometriosis is one of the most common disorders that causes infertility in women. Iron is overloaded in endometriosis peritoneal fluid (PF), with harmful effects on early embryo development. However, the mechanism by which endometriosis peritoneal fluid affects embryonic development remains unclear. Hence, this study investigated the effect of iron overload on mouse embryos and elucidated the molecular mechanism. Iron overload in endometriosis PF disrupted blastocyst formation, decreased GPX4 expression and induced lipid peroxidation, suggesting that iron overload causes embryotoxicity and induces ferroptosis. Moreover, mitochondrial damage occurs in iron overload-treated embryos, presenting as decreased ATP levels, increased ROS levels and MMP hyperpolarization. The cytotoxicity of iron overload is attenuated by the ferroptosis inhibitor Fer-1. Furthermore, Smart-seq analysis revealed that HMOX1 is upregulated in embryo ferroptosis and that HMOX1 suppresses ferroptosis by maintaining mitochondrial function. This study provides new insight into the mechanism of endometriosis infertility and a potential target for future endometriosis infertility treatment efforts.

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64 Culture of bovine oocytes and embryos with metabolic hormones concentrations associated with equine metabolic syndrome

Reproduction Fertility and Development ◽

10.1071/rdv31n1ab64 ◽

2019 ◽

Vol 31 (1) ◽

pp. 157

Author(s):

D. Bresnahan ◽

E. Carnevale

Keyword(s):

Gene Expression ◽

Metabolic Syndrome ◽

Embryo Development ◽

Early Embryo ◽

Blastocyst Formation ◽

Early Embryo Development ◽

Metabolic Hormones ◽

Equine Metabolic Syndrome ◽

And Control ◽

The Impact

Maternal metabolic status could affect fertility and early embryo development due to altered concentrations of metabolic hormones. Equine metabolic syndrome (EMS) is a condition in horses associated with obesity and insulin resistance. Equine metabolic syndrome is accompanied by increased concentrations of insulin and leptin and decreased concentrations of adiponectin, in ovarian follicular fluid (FF) and in systemic circulation (SYST). We sought to determine how altered concentrations of insulin, leptin, and adiponectin (ILA), consistent with those in mares with EMS (EMS) or normal mares (normal), would affect blastocyst formation rates, blastocyst gene expression for metabolism and inner cell mass formation (OCT4, SOX2, COX2, DNMT3a1, HK2, LDH, PDH, and GLUT1), and metabolite uptake from culture media. Because equine oocytes are not available for large-scale study, a bovine model was used in this preliminary study to determine the impact of altered ILA on oocytes and embryos. Bovine ovaries were obtained from an abattoir and embryos produced as previously described using chemically defined media (CDM; Barcelo-Fimbres and Seidel 2007Mol. Reprod. Dev. 74, 1406-1418). Briefly, oocytes were cultured in in vitro maturation medium (IVM), fertilized in FCDM, presumptive zygotes were placed into CDM-1 for ~56h. Cleavage rates were assessed, and embryos were moved to CDM-2 for ~122 additional hours. Treatments consisted of 5 groups: (1) standard oocyte IVM, FCDM and embryo production (EP) system (control), (2) IVM with normal FF ILA and control FCDM and EP, (3) IVM with normal FF ILA and FCDM and EP with normal SYST ILA, (4) IVM with EMS FF ILA and control FCDM and EP, and (5) IVM with EMS FF ILA and FCDM and EP with EMS SYST ILA. Seven days after fertilization, blastocysts were pooled in groups of 5 and placed into 50mL of CDM-2 for 24h. Embryos were removed, and medium was frozen and stored at −80°C to determine metabolite usage via gas chromatography mass spectroscopy. Pooled embryos were washed and placed into RNA lysis solution for relative quantitative PCR. Statistical comparisons were performed using ANOVA with a post-hoc Tukey test. Blastocyst formation rates and gene expression of viability markers were not significantly different among groups. However, aspartate was lower (P=0.02) in spent media from Group 3 (normal FF and SYST ILA) and tended (P=0.09) to be lower in media from Group 5 (EMS FF and SYST ILA) when compared with controls (Group 1). The ILA during early embryo development but not oocyte maturation appeared to be associated with increased uptake of aspartate, a nonessential amino acid, thought to be involved in osmoregulation, cellular signalling, and in mouse embryos, facilitate the metabolism of lactate. In conclusion, the addition of ILA in concentrations observed in normal horses and EMS horses did not affect blastocyst formation rates or markers of embryo viability, although embryo metabolism could have been altered.

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228 EFFECT OF INSULIN ON BOVINE OOCYTE MATURATION, CUMULUS CELL APOPTOSIS, AND EARLY EMBRYO DEVELOPMENT IN VITRO

Reproduction Fertility and Development ◽

10.1071/rdv27n1ab228 ◽

2015 ◽

Vol 27 (1) ◽

pp. 203

Author(s):

I. Lindgren ◽

P. Humblot ◽

D. Laskowski ◽

Y. Sjunnesson

Keyword(s):

Embryo Development ◽

Oocyte Maturation ◽

In Vitro Maturation ◽

Insulin Treatment ◽

Cumulus Cells ◽

Early Embryo ◽

Blastocyst Formation ◽

Early Embryo Development ◽

Maturation In Vitro

Dairy cow fertility has decreased during the last decades, and much evidence indicates that metabolic disorders are an important part of this decline. Insulin is a key factor in the metabolic challenge during the transition period that coincides with the oocyte maturation and may therefore have an impact on the early embryo development. The aim of this study was to test the effect of insulin during oocyte maturation on early embryo development by adding insulin during the oocyte maturation in vitro. In this study, abattoir-derived bovine ovaries were used and cumulus-oocyte complexes (n = 991) were in vitro matured for 22 h according to standard protocols. Insulin was added during maturation in vitro as follows: H (10 µg mL–1 of insulin), L (0.1 µg mL–1 of insulin), or Z (0 µg mL–1 of insulin). After maturation, oocytes were removed and fixed in paraformaldehyde before staining. Click-it TUNEL assay (Invitrogen, Stockholm, Sweden) was used for apoptotic staining and DRAQ5 (BioNordika, Stockholm, Sweden) for nuclear staining (n = 132). Cumulus-oocyte complexes were evaluated using laser scanning confocal microscope (Zeiss LSM 510, Zeiss, Oberkochen, Germany). Five levels of scans were used to assess oocyte maturation (MII stage) and apoptosis. Because of incomplete penetration of the TUNEL stain (3–5 layers of cumulus cells), only the outer 2 layers of the cumulus complex were investigated regarding apoptosis. Apoptotic index was calculated as apoptotic cells/total cells visualised. Remaining oocytes were fertilized and cultured in vitro until Day 8. Day 7 and Day 8 blastocyst formation was assessed as well as blastocyst stage and grade. Effect of insulin treatment on variables was analysed by ANOVA following arc sin √p transformation. Post-ANOVA comparisons between H+L group v. Z were performed by using the contrast option under GLM (Scheffé test). Results are presented as least squares means ± s.e. P-values ≤ 0.05 were considered as statistically significant. Insulin treatment during oocyte maturation in vitro had no significant effect on oocyte nuclear maturation or apoptotic index of the cumulus cells (Z: 0.052 ± 0.025, L: 0.039 ± 0.016, H: 0.077 ± 0.044, P > 0.05). No effect was seen on cleavage rates (Z: 0.85 ± 0.02, L: 0.85 ± 0.02, H: 0.89 ± 0.03, P > 0.05), but insulin treatment significantly decreased Day 7 rates from fertilized oocytes (Z: 0.19 ± 0.02, L: 0.14 ± 0.02, H: 0.12 ± 0.02, P < 0.05). This study also showed a significantly retarded developmental stage and decreased grade of blastocysts in insulin-treated groups taken together when compared with the control group (P < 0.05). In this study, no effect of insulin supplementation during in vitro maturation was seen on bovine oocyte maturation and apoptosis of cumulus cells, but blastocyst formation and development were negatively affected. Further studies are needed for understanding the relationship between the addition of insulin during maturation in vitro and impaired blastocyst formation. Insulin is a common supplement in the first phase of the first in vitro maturation medium for pig oocytes and is believed to have a beneficial effect on this species.Funding was received from Stiftelsen Nils Lagerlöfs Fond H12–0051-NLA.

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Calcium-sensing receptor (CASR) is involved in porcine in vitro fertilisation and early embryo development

Reproduction Fertility and Development ◽

10.1071/rd16338 ◽

2018 ◽

Vol 30 (2) ◽

pp. 391 ◽

Cited By ~ 4

Author(s):

C. Liu ◽

Y. Liu ◽

K. Larsen ◽

Y. P. Hou ◽

H. Callesen

Keyword(s):

Embryo Development ◽

Early Embryo ◽

Extracellular Calcium ◽

In Vitro Fertilisation ◽

Control Group ◽

Blastocyst Formation ◽

Calcium Sensing Receptor ◽

Early Embryo Development ◽

Calcium Sensing

It has been demonstrated that extracellular calcium is necessary in fertilisation and embryo development but the mechanism is still not well understood. The present study mainly focussed on the extracellular calcium effector called the calcium-sensing receptor (CASR) and examined its expression in porcine gametes and embryos and its function during fertilisation and early embryo development. By using reverse transcription polymerase chain reaction, CASR was found to be expressed in porcine oocytes, spermatozoa and embryos at different developmental stages. Functionally, medium supplementation with a CASR agonist or an antagonist during in vitro fertilisation (IVF) and in vitro culture (IVC) was tested. During fertilisation, the presence of a CASR agonist increased sperm penetration rate and decreased polyspermy rate leading to an increased normal fertilisation rate. During embryo development, for the IVF embryos, agonist treatment during IVC significantly increased cleavage rate and blastocyst formation rate compared with the control group. Furthermore, parthenogenetically activated embryos showed similar results with lower cleavage and blastocyst formation rates in the antagonist group than in the other groups. It was concluded that CASR, as the effector of extracellular calcium, modulates porcine fertilisation and early embryo development.

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Inferring simple but precise quantitative models of human oocyte and early embryo development

Journal of The Royal Society Interface ◽

10.1098/rsif.2021.0475 ◽

2021 ◽

Vol 18 (182) ◽

pp. 20210475

Author(s):

Brian D. Leahy ◽

Catherine Racowsky ◽

Daniel Needleman

Keyword(s):

Embryo Development ◽

Oocyte Maturation ◽

Statistical Physics ◽

Early Embryo ◽

Data Driven ◽

Human Oocyte ◽

Early Embryo Development ◽

Data Driven Approach ◽

Insight Into

Macroscopic, phenomenological models are useful as concise framings of our understandings in fields from statistical physics to finance to biology. Constructing a phenomenological model for development would provide a framework for understanding the complicated, regulatory nature of oogenesis and embryogenesis. Here, we use a data-driven approach to infer quantitative, precise models of human oocyte maturation and pre-implantation embryo development, by analysing clinical in-vitro fertilization (IVF) data on 7399 IVF cycles resulting in 57 827 embryos. Surprisingly, we find that both oocyte maturation and early embryo development are quantitatively described by simple models with minimal interactions. This simplicity suggests that oogenesis and embryogenesis are composed of modular processes that are relatively siloed from one another. In particular, our analysis provides strong evidence that (i) pre-antral follicles produce anti-Müllerian hormone independently of effects from other follicles, (ii) oocytes mature to metaphase-II independently of the woman’s age, her BMI and other factors, (iii) early embryo development is memoryless for the variables assessed here, in that the probability of an embryo transitioning from its current developmental stage to the next is independent of its previous stage. Our results both provide insight into the fundamentals of oogenesis and embryogenesis and have implications for the clinical IVF.

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Role of Nucleation-Promoting Factors in Mouse Early Embryo Development

Microscopy and Microanalysis ◽

10.1017/s1431927613000032 ◽

2013 ◽

Vol 19 (3) ◽

pp. 559-564 ◽

Cited By ~ 5

Author(s):

Qiao-Chu Wang ◽

Jun Liu ◽

Fei Wang ◽

Xing Duan ◽

Xiao-Xin Dai ◽

...

Keyword(s):

Cell Division ◽

Early Embryo ◽

Mouse Embryos ◽

Intensity Analysis ◽

Actin Assembly ◽

Early Embryo Development ◽

Multiple Processes ◽

Mouse Early Embryo ◽

Mammalian Embryos

AbstractDuring mitosis nucleation-promoting factors (NPFs) bind to the Arp2/3 complex and activate actin assembly. JMY and WAVE2 are two critical members of the NPFs. Previous studies have demonstrated that NPFs promote multiple processes such as cell migration and cytokinesis. However, the role of NPFs in development of mammalian embryos is still unknown. Results of the present study show that the NPFs JMY and WAVE2 are critical for cytokinesis during development of mouse embryos. Both JMY and WAVE2 are expressed in mouse embryos. After injection of JMY or WAVE2 siRNA, all embryos failed to develop to the morula or blastocyst stages. Moreover, using fluorescence intensity analysis, we found that the expression of actin decreased, and multiple nuclei were observed within a single cell indicating that NPFs-induced actin reduction caused the failure of cell division. In addition, injection of JMY and WAVE2 siRNA also caused ARP2 degradation, indicating that involvement of NPFs in development of mouse embryos is mainly through regulation of ARP2/3-induced actin assembly. Taken together, these data suggested that WAVE2 and JMY are involved in development of mouse embryos, and their regulation may be through a NPFs-Arp2/3-actin pathway.

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Oxidative stress induced by methomyl exposure reduces the quality of early embryo development in mice

Zygote ◽

10.1017/s0967199421000277 ◽

2021 ◽

pp. 1-8

Author(s):

Daohong He ◽

Guobo Han ◽

Xiaomeng Zhang ◽

Jingyu Sun ◽

Yongnan Xu ◽

...

Keyword(s):

Oxidative Stress ◽

Embryonic Development ◽

Embryo Development ◽

Early Embryo ◽

Early Embryonic Development ◽

Control Group ◽

Blastocyst Formation ◽

Early Embryo Development ◽

Early Embryos

Summary Methomyl is a widely used carbamate insecticide and environmental oestrogen that has adverse effects on the reproductive system. However, there have been no reports on the effect of methomyl on early embryos in mammals. In this study, we explored the effect of methomyl exposure on the quality of early embryonic development in mice and the possible mechanisms. During in vitro culture, different concentrations of methomyl (10, 20, 30 and 35 μM) were added to mouse zygote medium. The results showed that methomyl had an adverse effect on early embryonic development. Compared with the control group, the addition of 30 μM methomyl significantly reduced the rate of early embryo blastocyst formation. Methomyl exposure can increase oxidative stress and impair mitochondrial function, which may be the cause of blastocyst formation. In addition, we found that methomyl exposure promoted apoptosis and autophagy in mouse blastocysts. The toxic effect of methomyl on early embryos may be the result of oxidative stress induction. Taken together, our results indicate that methomyl can cause embryonic development defects in mice, thereby reducing the quality of early embryo development.

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Nanopore long-read RNA-seq and absolute quantification delineate transcription dynamics in early embryo development of an insect pest

Scientific Reports ◽

10.1038/s41598-021-86753-7 ◽

2021 ◽

Vol 11 (1) ◽

Author(s):

Anthony Bayega ◽

Spyros Oikonomopoulos ◽

Maria-Eleni Gregoriou ◽

Konstantina T. Tsoumani ◽

Antonis Giakountis ◽

...

Keyword(s):

Embryo Development ◽

Fruit Fly ◽

Early Embryo ◽

Olive Fruit Fly ◽

Rna Seq ◽

Early Embryo Development ◽

Olive Fruit ◽

Transcript Quantification ◽

Long Read ◽

Insight Into

AbstractThe olive fruit fly, Bactrocera oleae, is the most important pest for the olive fruit but lacks adequate transcriptomic characterization that could aid in molecular control approaches. We apply nanopore long-read RNA-seq with internal RNA standards allowing absolute transcript quantification to analyze transcription dynamics during early embryo development for the first time in this organism. Sequencing on the MinION platform generated over 31 million reads. Over 50% of the expressed genes had at least one read covering its entire length validating our full-length approach. We generated a de novo transcriptome assembly and identified 1768 new genes and a total of 79,810 isoforms; a fourfold increase in transcriptome diversity compared to the current NCBI predicted transcriptome. Absolute transcript quantification per embryo allowed an insight into the dramatic re-organization of maternal transcripts. We further identified Zelda as a possible regulator of early zygotic genome activation in B. oleae and provide further insights into the maternal-to-zygotic transition. These data show the utility of long-read RNA in improving characterization of non-model organisms that lack a fully annotated genome, provide potential targets for sterile insect technic approaches, and provide the first insight into the transcriptome landscape of the developing olive fruit fly embryo.

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Minor Splicing Factors Zrsr1 and Zrsr2 Essential for Gametogenesis, Early Embryo Development and Conversion of Stem Cells into 2C-Like

SSRN Electronic Journal ◽

10.2139/ssrn.3367197 ◽

2019 ◽

Author(s):

Isabel Gómez-Redondo ◽

Priscila Ramos-Ibeas ◽

Eva Pericuesta ◽

Benjamín Planells ◽

Raul Fernández-González ◽

...

Keyword(s):

Stem Cells ◽

Embryo Development ◽

Early Embryo ◽

Splicing Factors ◽

Early Embryo Development

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LIN28 coordinately promotes nucleolar/ribosomal functions and represses the 2C-like transcriptional program in pluripotent stem cells

Protein & Cell ◽

10.1007/s13238-021-00864-5 ◽

2021 ◽

Author(s):

Zhen Sun ◽

Hua Yu ◽

Jing Zhao ◽

Tianyu Tan ◽

Hongru Pan ◽

...

Keyword(s):

Stem Cells ◽

Embryo Development ◽

Pluripotent Stem Cells ◽

Rna Binding ◽

Stem Cell Differentiation ◽

Early Embryo ◽

Transcriptional Program ◽

Cell Stage ◽

Early Embryo Development ◽

Nucleolar Stress

AbstractLIN28 is an RNA binding protein with important roles in early embryo development, stem cell differentiation/reprogramming, tumorigenesis and metabolism. Previous studies have focused mainly on its role in the cytosol where it interacts with Let-7 microRNA precursors or mRNAs, and few have addressed LIN28’s role within the nucleus. Here, we show that LIN28 displays dynamic temporal and spatial expression during murine embryo development. Maternal LIN28 expression drops upon exit from the 2-cell stage, and zygotic LIN28 protein is induced at the forming nucleolus during 4-cell to blastocyst stage development, to become dominantly expressed in the cytosol after implantation. In cultured pluripotent stem cells (PSCs), loss of LIN28 led to nucleolar stress and activation of a 2-cell/4-cell-like transcriptional program characterized by the expression of endogenous retrovirus genes. Mechanistically, LIN28 binds to small nucleolar RNAs and rRNA to maintain nucleolar integrity, and its loss leads to nucleolar phase separation defects, ribosomal stress and activation of P53 which in turn binds to and activates 2C transcription factor Dux. LIN28 also resides in a complex containing the nucleolar factor Nucleolin (NCL) and the transcriptional repressor TRIM28, and LIN28 loss leads to reduced occupancy of the NCL/TRIM28 complex on the Dux and rDNA loci, and thus de-repressed Dux and reduced rRNA expression. Lin28 knockout cells with nucleolar stress are more likely to assume a slowly cycling, translationally inert and anabolically inactive state, which is a part of previously unappreciated 2C-like transcriptional program. These findings elucidate novel roles for nucleolar LIN28 in PSCs, and a new mechanism linking 2C program and nucleolar functions in PSCs and early embryo development.

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Geminin deletion in mouse oocytes results in impaired embryo development and reduced fertility

Molecular Biology of the Cell ◽

10.1091/mbc.e15-06-0346 ◽

2016 ◽

Vol 27 (5) ◽

pp. 768-775 ◽

Cited By ~ 8

Author(s):

Xue-Shan Ma ◽

Fei Lin ◽

Zhong-Wei Wang ◽

Meng-Wen Hu ◽

Lin Huang ◽

...

Keyword(s):

Embryo Development ◽

Primordial Follicle ◽

Early Embryo ◽

Cell Cycle Checkpoint ◽

Low Fertility ◽

Early Embryo Development ◽

Damage Repair ◽

Cycle Checkpoint ◽

Oocyte Meiotic Maturation ◽

Zygote Stage

Geminin controls proper centrosome duplication, cell division, and differentiation. We investigated the function of geminin in oogenesis, fertilization, and early embryo development by deleting the geminin gene in oocytes from the primordial follicle stage. Oocyte-specific disruption of geminin results in low fertility in mice. Even though there was no evident anomaly of oogenesis, oocyte meiotic maturation, natural ovulation, or fertilization, early embryo development and implantation were impaired. The fertilized eggs derived from mutant mice showed developmental delay, and many were blocked at the late zygote stage. Cdt1 protein was decreased, whereas Chk1 and H2AX phosphorylation was increased, in fertilized eggs after geminin depletion. Our results suggest that disruption of maternal geminin may decrease Cdt1 expression and cause DNA rereplication, which then activates the cell cycle checkpoint and DNA damage repair and thus impairs early embryo development.

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