Defective zonae pellucidae in Zp2-null mice disrupt folliculogenesis, fertility and development

Development ◽  
2001 ◽  
Vol 128 (7) ◽  
pp. 1119-1126 ◽  
Author(s):  
T.L. Rankin ◽  
M. O'Brien ◽  
E. Lee ◽  
K. Wigglesworth ◽  
J. Eppig ◽  
...  
Keyword(s):  
Zona Pellucida ◽  
Embryonic Stem ◽  
Single Copy ◽  
Targeted Mutagenesis ◽  
Developmental Competence ◽  
Normal Male ◽  
Null Mouse ◽  
Developmental Potential ◽  
Early Embryos

All vertebrate eggs are surrounded by an extracellular matrix. This matrix is known as the zona pellucida in mammals and is critically important for the survival of growing oocytes, successful fertilization and the passage of early embryos through the oviduct. The mouse zona pellucida is composed of three glycoproteins (ZP1, ZP2 and ZP3), each encoded by a single copy gene. Using targeted mutagenesis in embryonic stem cells, Zp2-null mouse lines have been established. ZP1 and ZP3 proteins continue to be synthesized and form a thin zona matrix in early follicles that is not sustained in pre-ovulatory follicles. The abnormal zona matrix does not affect initial folliculogenesis, but there is a significant decrease in the number of antral stage follicles in ovaries isolated from mice lacking a zona pellucida. Few eggs are detected in the oviduct after stimulation with gonadotropins, and no two-cell embryos are recovered after mating Zp2-null females with normal male mice. The structural defect is more severe than that observed in Zp1-null mice, which have decreased fecundity, but not quite as severe as that observed in Zp3-null mice, which never form a visible zona pellucida and are sterile. Although zona-free oocytes matured and fertilized in vitro can progress to the blastocyst stage, the developmental potential of blastocysts derived from either Zp2- or Zp3-null eggs appears compromised and, after transfer to foster mothers, live births have not been observed. Thus, in addition to its role in fertilization and protection of early embryos, these data are consistent with the zona pellucida maintaining interactions between granulosa cells and oocytes during folliculogenesis that are critical to maximize developmental competence of oocytes.

scholarly journals Evaluation of bovine zona pellucida characteristics in polarized light as a prognostic marker for embryonic developmental potential

Reproduction ◽  
2011 ◽  
Vol 141 (6) ◽  
pp. 779-787 ◽  
Author(s):  
M Koester ◽  
A Mohammadi-Sangcheshmeh ◽  
M Montag ◽  
F Rings ◽  
T Schimming ◽  
...  
Keyword(s):  
Zona Pellucida ◽  
Polarized Light ◽  
Oocyte Quality ◽  
Developmental Competence ◽  
Blue Staining ◽  
Developmental Potential ◽  
Preimplantation Embryo Development ◽  
Intensity Parameters ◽  
Bovine Oocytes

It has previously been demonstrated that zona pellucida imaging of human oocytes using polarized light microscopy is a clinically applicable method for the noninvasive assessment of oocyte quality. This study was designed to investigate whether zona pellucida characteristics of bovine oocytes and zygotes in polarized light may similarly serve as a useful marker for developmental competence in bovine reproductive biotechnologies. Zona birefringence intensity parameters of 2862 oocytes/zygotes were objectively evaluated with an automatic analysis system and correlated with oocyte/zygote quality. In detail, immature oocytes of good quality assessed with brilliant cresyl blue staining showed significantly lower zona birefringence than poor-quality counterparts (P<0.001). Afterin vitromaturation and classification according to maturational status, the birefringence intensity parameters were significantly different in those oocytes that reached metaphase II compared with arrested stages (P<0.001). Following either parthenogenetic activation or IVF with subsequentin vitroculture in a well-of-the-well system until day 9, superior development as determined by cleavage, blastocyst formation, and hatching ability was associated with lower zona birefringence intensity parameters. When early zygote-stage embryos were selected and assorted in groups based on zona birefringence (high/medium/low), the group of embryos derived from high-birefringence zygotes displayed a significantly compromised developmental potential compared with low-birefringence zygotes. These results clearly show that developmentally competent bovine oocytes/zygotes exhibit lower zona birefringence intensity parameters. Therefore, birefringence imaging of zona pellucida is a suitable technique to predict bovine preimplantation embryo development.

P–219 mtDNA content in bovine cumulus cells does not predict oocytés developmental competence

2021 ◽  
Vol 36 (Supplement_1) ◽  
Author(s):  
Á Martíne. Moro ◽  
I Lamas-Toranzo ◽  
L González-Brusi ◽  
A Pérez-Gómez ◽  
P Bermejo-Álvarez
Keyword(s):  
Cumulus Cell ◽  
Cumulus Cells ◽  
Oocyte Quality ◽  
Blastocyst Stage ◽  
Early Embryo ◽  
Developmental Competence ◽  
Success Rates ◽  
Developmental Potential ◽  
Mtdna Sequence

Abstract Study question Does cumulus cell mtDNA content correlate with oocyte developmental potential in the bovine model? Summary answer The relative amount of mtDNA content did not vary significantly in oocytes showing different developmental outcomes following IVF What is known already Cumulus cells are closely connected to the oocyte through transzonal projections, serving essential metabolic functions during folliculogenesis. These oocyte-supporting cells are removed and discarded prior to ICSI, thereby constituting an interesting biological material on which to perform molecular analysis aimed to predict oocyte developmental competence. Previous studies have positively associated oocytés mtDNA content with developmental potential in both animal models and women. However, it remains debatable whether mtDNA content in cumulus cells could be used as a proxy to infer oocyte developmental potential. Study design, size, duration Bovine cumulus cells were allocated into three groups according to the developmental potential of the oocyte: 1) oocytes developing to blastocysts following IVF (Bl+Cl+), 2) oocytes cleaving following IVF but arresting their development prior to the blastocyst stage (Bl-Cl+), and 3) oocytes not cleaving following IVF (Bl-Cl-). Relative mtDNA content was analysed in 40 samples/group, each composed by the cumulus cells from one cumulus-oocyte complex (COC). Participants/materials, setting, methods Bovine cumulus-oocyte complexes were obtained from slaughtered cattle and individually matured in vitro (IVM). Following IVM, cumulus cells were removed by hyaluronidase treatment, pelleted, snap frozen in liquid nitrogen and stored at –80 ºC until analysis. Cumulus-free oocytes were fertilized and cultured in vitro individually and development was recorded for each oocyte. Relative mtDNA abundance was determined by qPCR, amplifying a mtDNA sequence (COX1) and a chromosomal sequence (PPIA). Statistical differences were tested by ANOVA. Main results and the role of chance Relative mtDNA abundance did not differ significantly (ANOVA p &gt; 0.05) between the three groups exhibiting different developmental potential (1±0.06 vs. 1.19±0.05 vs. 1.11±0.05, for Bl+Cl+ vs. Bl-Cl+ vs. Bl-Cl-, mean±s.e.m.). Limitations, reasons for caution Experiments were conducted in the bovine model. Although bovine folliculogenesis, monoovulatory ovulation and early embryo development exhibit considerable similarities with that of humans, caution should be taken when extrapolating these data to humans. Wider implications of the findings: The use of molecular markers for oocyte developmental potential in cumulus cells could be used to enhance success rates following single-embryo transfer. Unfortunately, mtDNA in cumulus cells was not found to be a good proxy for oocyte quality. Trial registration number Not applicable

The responsiveness of embryonic stem cells to alpha and beta interferons provides the basis of an inducible expression system for analysis of developmental control genes

1993 ◽  
Vol 13 (12) ◽  
pp. 7971-7976
Author(s):  
L M Whyatt ◽  
A Düwel ◽  
A G Smith ◽  
P D Rathjen
Keyword(s):  
Gene Expression ◽  
Inner Cell Mass ◽  
Es Cells ◽  
Expression System ◽  
Cell Mass ◽  
Embryonic Stem ◽  
Expression Vectors ◽  
Developmental Control ◽  
Developmental Potential

Embryonic stem (ES) cells, derived from the inner cell mass of the preimplantation mouse embryo, are used increasingly as an experimental tool for the investigation of early mammalian development. The differentiation of these cells in vitro can be used as an assay for factors that regulate early developmental decisions in the embryo, while the effects of altered gene expression during early embryogenesis can be analyzed in chimeric mice generated from modified ES cells. The experimental versatility of ES cells would be significantly increased by the development of systems which allow precise control of heterologous gene expression. In this paper, we report that ES cells are responsive to alpha and beta interferons (IFNs). This property has been exploited for the development of inducible ES cell expression vectors, using the promoter of the human IFN-inducible gene, 6-16. The properties of these vectors have been analyzed in both transiently and stably transfected ES cells. Expression was minimal or absent in unstimulated ES cells, could be stimulated up to 100-fold by treatment of the cells with IFN, and increased in linear fashion with increasing levels of IFN. High levels of induced expression were maintained for extended periods of time in the continuous presence of the inducing signal or following a 12-h pulse with IFN. Treatment of ES cells with IFN did not affect their growth or differentiation in vitro or compromise their developmental potential. This combination of features makes the 6-16-based expression vectors suitable for the functional analysis of developmental control control genes in ES cells.

Induction of autophagy protects against extreme hypoxia-induced damage in porcine embryo

Reproduction ◽  
2021 ◽  
Vol 161 (4) ◽  
pp. 353-363
Author(s):  
Mun-Hyeong Lee ◽  
Pil-Soo Jeong ◽  
Bo-Woong Sim ◽  
Hyo-Gu Kang ◽  
Min Ju Kim ◽  
...  
Keyword(s):  
Oxygen Tension ◽  
Early Phase ◽  
Inner Cell Mass ◽  
Formation Rate ◽  
Cell Mass ◽  
Female Reproductive Tract ◽  
Developmental Competence ◽  
Early Embryos ◽  
Developmental Parameters

In the mammalian female reproductive tract, physiological oxygen tension is lower than that of the atmosphere. Therefore, to mimic in vivo conditions during in vitro culture (IVC) of mammalian early embryos, 5% oxygen has been extensively used instead of 20%. However, the potential effect of hypoxia on the yield of early embryos with high developmental competence remains unknown or controversial, especially in pigs. In the present study, we examined the effects of low oxygen tension under different oxygen tension levels on early developmental competence of parthenogenetically activated (PA) and in vitro-fertilized (IVF) porcine embryos. Unlike the 5% and 20% oxygen groups, exposure of PA embryos to 1% oxygen tension, especially in early-phase IVC (0–2 days), greatly decreased several developmental competence parameters including blastocyst formation rate, blastocyst size, total cell number, inner cell mass (ICM) to trophectoderm (TE) ratio, and cellular survival rate. In contrast, 1% oxygen tension did not affect developmental parameters during the middle (2–4 days) and late phases (4–6 days) of IVC. Interestingly, induction of autophagy by rapamycin treatment markedly restored the developmental parameters of PA and IVF embryos cultured with 1% oxygen tension during early-phase IVC, to meet the levels of the other groups. Together, these results suggest that the early development of porcine embryos depends on crosstalk between oxygen tension and autophagy. Future studies of this relationship should explore the developmental events governing early embryonic development to produce embryos with high developmental competence in vitro.

scholarly journals Transcriptome dynamics in early in vivo developing and in vitro produced porcine embryos

2020 ◽  
Author(s):  
Vera A van der Weijden ◽  
Meret Schmidhauser ◽  
Mayuko Kurome ◽  
Johannes Knubben ◽  
Veronika L Flöter ◽  
...  
Keyword(s):  
Signaling Pathways ◽  
Early Stage ◽  
Developmental Competence ◽  
Molecular Signaling ◽  
Developmental Potential ◽  
Stage Of Development ◽  
Molecular Signaling Pathways ◽  
Canonical Pathways

Abstract Background: The transcriptional changes around the time of embryonic genome activation in pre-implantation embryos indicate that this process is highly dynamic. In vitro produced porcine blastocysts are known to be less competent than in vivo developed blastocysts. To understand the conditions that compromise developmental competence of in vitro embryos, it is crucial to evaluate the transcriptional profile of porcine embryos during pre-implantation stages. In this study, we investigated the transcriptome dynamics in in vivo developed and in vitro produced 4-cell embryos, morulae and hatched blastocysts.Results: In vivo developed and in vitro produced embryos displayed largely similar transcriptome profiles during development. Enriched canonical pathways from the 4-cell to the morula transition that were shared between in vivo developed and in vitro produced embryos included oxidative phosphorylation, tRNA charging, and EIF2 signaling. The shared canonical pathways from the morula to the hatched blastocyst transition were 14-3-3-mediated signaling, signaling of Rho family GTPases, and NRF2-mediated oxidative stress response. The in vivo developed and in vitro produced hatched blastocysts were compared to identify molecular signaling pathways indicative of lower developmental competence of in vitro produced hatched blastocysts. A higher metabolic rate and expression of the arginine transporter SLC7A1 were found in in vitro produced hatched blastocysts.Conclusions: Our findings suggest that embryos with compromised developmental potential are arrested at an early stage of development, while embryos developing to the hatched blastocyst stage display largely similar transcriptome profiles, irrespective of the embryo source. The hatched blastocysts derived from the in vitro fertilization-pipeline showed an enrichment in molecular signaling pathways associated with lower developmental competence, compared to the in vivo developed embryos.

The analysis of chromatin organisation allows selection of mouse antral oocytes competent for development to blastocyst

Zygote ◽  
2002 ◽  
Vol 10 (1) ◽  
pp. 73-78 ◽  
Author(s):  
Maurizio Zuccotti ◽  
Rubén H. Ponce ◽  
Michele Boiani ◽  
Stefano Guizzardi ◽  
Paolo Govoni ◽  
...  
Keyword(s):  
Developmental Competence ◽  
Farm Animals ◽  
Cell Stage ◽  
Developmental Potential ◽  
Different Types ◽  
Chromatin Organisation ◽  
Selection For ◽  
Gamete Selection ◽  
Selection Of

Mouse antral oocytes can be classified in two different types termed SN or NSN oocytes, depending on the presence or absence, respectively, of a ring of Hoechst 33342-positive chromatin surrounding the nucleolus. The aim of the present study was to test the developmental competence to blastocyst of the two types of oocytes. Here we show that following isolation, classification and culture of cumulus-free antral oocytes, 14.7% and 74.5% of NSN and SN oocytes, respectively, reached the metaphase II stage. When fertilised and further cultured none of the metaphase II NSN oocytes developed beyond the 2-cell stage whilst 47.4% of the metaphase II SN oocytes reached the 4-cell stage and 18.4% developed to blastocyst. The findings reported in this paper may contribute to improved procedures of female gamete selection for in vitro fertilisation of humans and farm animals. Furthermore, the selection of oocytes with better developmental potential may be of interest for studies on nuclear/cytoplasm interaction, particularly in nuclear-transfer experiments.

scholarly journals MicroRNAs from Extracellular Vesicles Secreted by Bovine Embryos as Early Biomarkers of Developmental Competence

2020 ◽  
Vol 21 (23) ◽  
pp. 8888
Author(s):  
Bárbara Melo-Baez ◽  
Yat S. Wong ◽  
Constanza J. Aguilera ◽  
Joel Cabezas ◽  
Ana C. F. Mançanares ◽  
...  
Keyword(s):  
Extracellular Vesicles ◽  
Fatty Acid Biosynthesis ◽  
Culture Media ◽  
Blastocyst Stage ◽  
Developmental Competence ◽  
Target Cells ◽  
Bovine Embryos ◽  
Developmental Potential ◽  
Maternal Communication

During early development, embryos secrete extracellular vesicles (EVs) that participate in embryo–maternal communication. Among other molecules, EVs carry microRNAs (miRNAs) that interfere with gene expression in target cells; miRNAs participate in embryo–maternal communication. Embryo selection based on secreted miRNAs may have an impact on bovine breeding programs. This research aimed to evaluate the size, concentration, and miRNA content of EVs secreted by bovine embryos with different developmental potential, during the compaction period (days 3.5–5). Individual culture media from in vitro–produced embryos were collected at day 5, while embryos were further cultured and classified at day 7, as G1 (conditioned-culture media by embryos arrested in the 8–16-cells stage) and G2 (conditioned-culture media by embryos that reached blastocyst stages at day 7). Collected nanoparticles from embryo conditioned culture media were cataloged as EVs by their morphology and the presence of classical molecular markers. Size and concentration of EVs from G1 were higher than EVs secreted by G2. We identified 95 miRNAs; bta-miR-103, bta-miR-502a, bta-miR-100, and bta-miR-1 were upregulated in G1, whereas bta-miR-92a, bta-miR-140, bta-miR-2285a, and bta-miR-222 were downregulated. The most significant upregulated pathways were fatty acid biosynthesis and metabolism, lysine degradation, gap junction, and signaling pathways regulating pluripotency of stem cells. The characteristics of EVs secreted by bovine embryos during the compaction period vary according to embryo competence. Embryos that reach the blastocyst stage secrete fewer and smaller vesicles. Furthermore, the loading of specific miRNAs into the EVs depends on embryo developmental competence.

scholarly journals In vivo and in vitro maturation of rabbit oocytes differently affects the gene expression profile, mitochondrial distribution, apoptosis and early embryo development

2017 ◽  
Vol 29 (9) ◽  
pp. 1667 ◽  
Author(s):  
M. Arias-Álvarez ◽  
R. M. García-García ◽  
J. López-Tello ◽  
P. G. Rebollar ◽  
A. Gutiérrez-Adán ◽  
...  
Keyword(s):  
Gene Expression ◽  
Rabbit Model ◽  
Developmental Competence ◽  
Gene Markers ◽  
Developmental Potential ◽  
Junction Protein ◽  
Mitochondrial Distribution ◽  
Potential Biomarkers

In vivo-matured cumulus–oocyte complexes are valuable models in which to assess potential biomarkers of rabbit oocyte quality that contribute to enhanced IVM systems. In the present study we compared some gene markers of oocytes and cumulus cells (CCs) from immature, in vivo-matured and IVM oocytes. Moreover, apoptosis in CCs, nuclear maturation, mitochondrial reallocation and the developmental potential of oocytes after IVF were assessed. In relation to cumulus expansion, gene expression of gap junction protein, alpha 1, 43 kDa (Gja1) and prostaglandin-endoperoxide synthase 2 (Ptgs2) was significantly lower in CCs after in vivo maturation than IVM. In addition, there were differences in gene expression after in vivo maturation versus IVM in both oocytes and CCs for genes related to cell cycle regulation and apoptosis (V-Akt murine thymoma viral oncogene homologue 1 (Akt1), tumour protein 53 (Tp53), caspase 3, apoptosis-related cysteine protease (Casp3)), oxidative response (superoxide dismutase 2, mitochondrial (Sod2)) and metabolism (glucose-6-phosphate dehydrogenase (G6pd), glyceraldehyde-3-phosphate dehydrogenase (Gapdh)). In vivo-matured CCs had a lower apoptosis rate than IVM and immature CCs. Meiotic progression, mitochondrial migration to the periphery and developmental competence were higher for in vivo-matured than IVM oocytes. In conclusion, differences in oocyte developmental capacity after IVM or in vivo maturation are accompanied by significant changes in transcript abundance in oocytes and their surrounding CCs, meiotic rate, mitochondrial distribution and apoptotic index. Some of the genes investigated, such as Gja1, could be potential biomarkers for oocyte developmental competence in the rabbit model, helping improve in vitro culture systems in these species.

Improvement of the developmental competence of canine oocyte using caffeine supplementation during IVM at different maturation time

Zygote ◽  
2018 ◽  
Vol 26 (2) ◽  
pp. 162-167 ◽  
Author(s):  
Mohamed Fathi ◽  
A. Salama ◽  
Magdy R. Badr
Keyword(s):  
Developmental Competence ◽  
Control Group ◽  
Free Medium ◽  
Maturation Time ◽  
Fluid Medium ◽  
Developmental Potential ◽  
Nuclear Maturation ◽  
Maturation Medium ◽  
Oviductal Fluid

SummaryThe aim of the current study was to investigate the effect of caffeine supplementation during in vitro maturation (IVM) for different maturation times on the developmental potential of canine oocytes recovered from ovariohysterectomized bitches. The recovered cumulus–oocytes complexes were in vitro matured for 72 h. Here, 10 mM caffeine was added to the maturation medium for different incubation times (caffeine from 0–72 h maturation, caffeine for the first 24 h of maturation only, caffeine addition from 24 to 48 h maturation time, caffeine addition from 48 to 72 h maturation or in caffeine-free medium, control group). The matured oocytes were in vitro fertilized using frozen–thawed spermatozoa. The presumptive zygotes were in vitro cultured in synthetic oviductal fluid medium for 5 days. The results showed that both maturation and fertilization rates were significantly higher (P ˂ 0.05) using caffeine-treated medium for the first 24 h of maturation compared with the control and other two groups of caffeine treatment (from 24 to 48 h and from 48 to 72 h), whereas use of caffeine-treated medium for a 0–72 h incubation time did not affect these rates (P > 0.05). Interestingly, the matured oocytes in caffeine-supplemented medium for the first 24 h or from 0–72 h showed a significant (P ˂ 0.05) increase in the total number of cleaved embryos compared with the control group. In conclusion, supplementation of the maturation medium with 10 mM caffeine for the first 24 h of maturation or during the whole maturation time (0–72 h) improved nuclear maturation and subsequent embryo development preimplantation following in vitro fertilization.

58 HISTONE DEACETYLASES INHIBITOR, SCRIPTAID, IS BENEFICIAL TO THE REPROGRAMMING OF SOMATIC NUCLEI FOLLOWING NUCLEAR TRANSFER

2009 ◽  
Vol 21 (1) ◽  
pp. 129
Author(s):  
J. G. Zhao ◽  
J. W. Ross ◽  
Y. H. Hao ◽  
D. M. Wax ◽  
L. D. Spate ◽  
...  
Keyword(s):  
Histone Acetylation ◽  
Histone Deacetylases ◽  
Nuclear Transfer ◽  
Blastocyst Stage ◽  
Untreated Group ◽  
Developmental Competence ◽  
Developmental Potential ◽  
Reconstructed Embryos

Somatic cell nuclear transfer (SCNT) is a promising technology with potential applications in both agriculture and regenerative medicine. The reprogramming of differentiated somatic nuclei into totipotent embryonic state following NT is not efficient and the mechanism is currently unknown. However, accumulating evidence suggests that faulty epigenetic reprogramming is likely to be the major cause of low success rates observed in all mammals produced through SCNT. It has been demonstrated that increased histone acetylation in reconstructed embryos by applying histone deacetylases inhibitor (HDACi) such as trychostatin A (TSA) significantly enhanced the developmental competence in several species in vitro and in vivo. However TSA has been known to be teratogenic. Compared with TSA, Scriptaid is a low toxic but more efficient HDACi (Su GH et al. 2000 Cancer Res. 60, 3137–3142). The objectives of this study were: 1) to investigate and optimize the application Scriptaid to the NT using Landrace fetal fibroblast cells (FFCs) as donor; 2) investigate the effect of increased histone acetylation on the developmental competence of reconstructed embryos from NIH mini inbred FFCs in vitro and in vivo. The reconstructed embryos were treated with Scriptaid at different concentrations (0 nm, 250 nm, 500 nm and 1000 nm) after activation for 14 to 16 h. IVF embryos without treatment were produced as an additional control. Developmental rates to the 2-cell and blastocyst stage were determined. Developmental potential was determined by transferring Day 1 NT zygotes to the oviducts of surrogates on the day of, or one day after, the onset of estrus. Experiments were repeated at least 3 times and data were analyzed with chi-square tests using SAS 6.12 program (SAS institute, Inc., Cary, NC, USA). The percentage blastocyst of cloned embryos using Landrace FFCs as donors treated with 500 nm Scriptaid was the highest and was significantly higher than untreated group (25% v. 11%, P < 0.05). Percent cleaved was not different among four treatment groups. We used 500 nm Scriptaid for 14 to 16 h after activation for all subsequent experiments. Developmental rate to the blastocyst stage was significantly increased in cloned embryos derived from NIH mini inbred FFCs after treating with Scriptaid (21% v. 9%, P < 0.05), while the blastocyst rate in IVF group was 30%. Embryo transfer (ET) results showed that 5/6 (Transferred embryos No. were 190, 109, 154, 174, 152, and 190, respectively) surrogates (83%) became pregnant resulting in 2 healthy piglets from 2 litters (recipients received 190 and 154 embryos, respectively) in the Scriptaid treatment group, while no pregnancies were obtained in the untreated group from 5 ET (Embryos transferred No. are 140, 163, 161, 151 and 151, respectively). These results suggest that 500 nm Scriptaid treatment following activation increase both the in vitro and in vivo development of porcine SCNT embryos from NIH mini inbred FFCs and the hyperacetylation might actually improve reprogramming of the somatic nuclei after NT. Funding from the National Institutes of Health National Center for Research Resources RR018877.

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