scholarly journals Early Embryonic Development of a Polyembryonic Wasp, Litomastix maculata ISHII, in vivo and in vitro

1991 ◽  
Vol 26 (4) ◽  
pp. 563-570 ◽  
Author(s):  
Kikuo IWABUCHI
Keyword(s):  
Embryonic Development ◽  
Early Embryonic Development

scholarly journals Morphological features of lipid droplet transition during porcine oocyte fertilisation and early embryonic development to blastocyst in vivo and in vitro

Zygote ◽  
2002 ◽  
Vol 10 (4) ◽  
pp. 355-366 ◽  
Author(s):  
Kazuhiro Kikuchi ◽  
Hans Ekwall ◽  
Paisan Tienthai ◽  
Yasuhiro Kawai ◽  
Junko Noguchi ◽  
...  
Keyword(s):  
Embryonic Development ◽  
Oocyte Maturation ◽  
Lipid Droplets ◽  
Early Embryonic Development ◽  
Oocyte Activation ◽  
Energy Status ◽  
Thin Sections ◽  
Porcine Oocyte

Lipid content in mammalian oocytes or embryos differs among species, with bovine and porcine oocytes and embryos showing large cytoplasmic droplets. These droplets are considered to play important roles in energy metabolism during oocyte maturation, fertilisation and early embryonic development, and also in the freezing ability of oocytes or embryos; however, their detailed distribution or function is not well understood. In the present study, changes in the distribution and morphology of porcine lipid droplets during in vivo and in vitro fertilisation, in contrast to parthenogenetic oocyte activation, as well as during their development to blastocyst stage, were evaluated by transmission electron microscopy (TEM). The analysis of semi-thin and ultra-thin sections by TEM showed conspicuous, large, electron-dense lipid droplets, sometimes associated with mitochondrial aggregates in the oocytes, irrespective of whether the oocytes had been matured in vivo or in vitro. Immediately after sperm penetration, the electron density of the lipid droplets was lost in both the in vivo and in vitro oocytes, the reduction being most evident in the oocytes developed in vitro. Density was restored in the pronculear oocytes, fully in the in vivo specimens but only partially in the in vitro ones. The number and size of the droplets seemed, however, to have decreased. At 2- to 4-cell and blastocyst stages, the features of the lipid droplets were almost the same as those of pronuclear oocytes, showing a homogeneous or saturated density in the in vivo embryos but a marbled or partially saturated appearance in the in vitro embryos. In vitro matured oocytes undergoing parthenogenesis had lipid droplets that resembled those of fertilised oocytes until the pronuclear stage. Overall, results indicate variations in both the morphology and amount of cytoplasmic lipid droplets during porcine oocyte maturation, fertilisation and early embryo development as well as differences between in vivo and in vitro development, suggesting both different energy status during preimplantation development in pigs and substantial differences between in vitro and in vivo development.

200 SYNCHRONIZATION OF OOCYTE MEIOTIC MATURATION IN SUPEROVULATED MICE IMPROVES IN VITRO FERTILIZATION RATE

2012 ◽  
Vol 24 (1) ◽  
pp. 212
Author(s):  
A. M. Taiyeb Ridha ◽  
D. C. Kraemer
Keyword(s):  
Embryonic Development ◽  
Fertilization Rate ◽  
Early Embryonic Development ◽  
Meiotic Maturation ◽  
Control Group ◽  
Vitro Fertilization ◽  
Development Rates ◽  
Oocyte Meiotic Maturation

In vitro synchronization of oocyte nuclear and cytoplasmic maturation has been found to improve the IVF rate of ovarian oocytes in several species, including humans, in comparison with nonsynchronized in vitro-matured oocytes. Here, we tested the hypothesis that synchronization of oocyte meiotic maturation by an in vivo system in superovulated mice would increase the oocyte fertilization rate when compared to that of conventional superovulated oocytes. Recently, we observed that cilostazol (CZL), a PDE3-I, was able to inhibit mouse oocyte meiotic maturation in both in vitro and in vivo systems. Administering CZL at 7.5 mg, 4 or 7 h pre-hCG allowed retrieval of ovulated oocytes of which >95% were at MI stage, scored by Nikon stereo microscope (SMZ 1500). A conventional superovulation program was adapted in all treated and their control groups, in which mice were injected with eCG and after 48 h with hCG (7.5 IU for each hormone). On the second morning, 13 to 14 h post-hCG, mice were killed and oocytes were collected from oviducts and in vitro fertilized (control). For the treated groups, CZL was administered in a single 7.5 mg oral dose (gavage) 4 or 7 h before the hCG injection. On the second morning, CZL-treated animals were killed at the same timing as control animals and oocytes were retrieved from the oviduct and in vitro matured for 6 h (for those gavaged with CZL, 4 h pre-hCG) or 3 h (for those gavaged with CZL, 7 h pre-hCG) to MII oocytes before IVF. These groups were designated as in vivo-in vitro synchronized/matured oocytes. In other groups treated with CZL, 4 or 7 h pre-hCG, the ovulated oocytes were allowed to mature in the oviduct (full in vivo synchronization and maturation) and oocytes were retrieved and fertilized with the same fertilization timings as the in vivo-in vitro synchronized/matured oocytes. Oocytes were cultured for 1 day after IVF and examined for cleavage. Statistical differences were analyzed by cross-tabulated chi-square test. The full in vivo synchronization and maturation (for both CZL dose timings of 4 and 7 h pre-hCG) gave significantly higher early embryonic development rates compared with those of the control [89% (n = 219) and 92.2% (n = 374) vs 81.8% (n = 198); P = 0.034 and P < 0.0001, respectively]. The in vivo-in vitro synchronized/matured oocytes (CZL dose timing at 7 h, but not 4 h pre-hCG) gave significantly higher early embryonic development rates compared with those of the control [88.5% (n = 339) vs 83.4% (n = 458), respectively; P = 0.043]. However, the increase of the IVF rate of the oocytes from mice treated with CZL, 4 h pre-hCG, in the in vivo-in vitro synchronized/matured group was not significantly different from the control group [88.5% (n = 399) vs 83.4% (n = 458), respectively; P = 0.43]. It is concluded from the present study that synchronization of oocyte meiotic maturation by the in vivo and in vivo-in-vitro protocols can increase the IVF rate of oocytes in superovulated mice.

Fertilization and early embryonic development of in vitro matured metaphase I oocytes in patients with unexpected low oocyte maturity rate

Zygote ◽  
2021 ◽  
pp. 1-5
Author(s):  
Nafiye Yılmaz ◽  
Şebnem Özyer ◽  
Derya Taş ◽  
Mehmet Caner Özer ◽  
Ayten Türkkanı ◽  
...  
Keyword(s):  
Embryonic Development ◽  
Fertilization Rate ◽  
Early Embryonic Development ◽  
Oocyte Maturity ◽  
Significant Difference ◽  
Maturation Rate ◽  
Developmental Capacity ◽  
Metaphase I

Summary To determine the fertilization and embryonic potential of immature metaphase I (MI) oocytes in patients with low oocyte maturity rate in whom the percentage of mature oocytes obtained was less than 75% of the total retrieved ones. In vivo matured metaphase II (MII) oocytes (MII-ICSI, n = 244), and in vitro matured MI oocytes (MI-MII-ICSI, n = 202) underwent an intracytoplasmic sperm injection (ICSI) procedure. Maturation rate, fertilization rate and early embryonic development were compared in both groups. In total, 683 oocytes were collected from 117 ICSI cycles of 117 patients. Among them, 244 (35.7%) were mature MII and 259 (37.9%) were MI after the denudation process. Of those 259 MI oocytes, 202 (77.9%) progressed to MII oocytes after an incubation period of 18–24 h. The maturation rate was 77.9%. Fertilization rate was found to be significantly higher in the rescued in vitro matured MI oocyte group when compared with the in vivo matured MII oocyte group (41.6% vs 25.8%; P = 0.0006). However, no significant difference was observed in terms of cleavage rates on days 2 and 3 between the groups (P = 0.9126 and P = 0.5031, respectively). There may be unidentified in vivo factors on the oocyte maturation causing low developmental capacity in spite of high fertilization rates in the group of patients with low oocyte maturity rate. Furthermore, studies are needed to determine the appropriate culture characteristics as well as culture period and ICSI timing of these oocytes.

RU486 inhibits ovulation, fertilization and early embryonic development in rabbits: in vivo and in vitro studies*

1995 ◽  
Vol 64 (3) ◽  
pp. 627-633 ◽  
Author(s):  
Serena H. Chen ◽  
Arunasalem M. Dharmarajan ◽  
Edward E. Wallach ◽  
Christos Mastroyannis
Keyword(s):  
Embryonic Development ◽  
In Vitro Studies ◽  
Early Embryonic Development

scholarly journals Human embryos in a dish – modeling early embryonic development with pluripotent stem cells

2022 ◽  
Vol 11 (1) ◽  
Author(s):  
Xiukun Wang ◽  
Guang Hu
Keyword(s):  
Stem Cell ◽  
Embryonic Development ◽  
Early Embryonic Development ◽  
Human Embryos ◽  
Blastocyst Development ◽  
Lineage Specification ◽  
Endometrial Cells ◽  
Early Human

AbstractStem cell-based embryo models present new opportunities to study early embryonic development. In a recent study, Kagawa et al. identified an approach to create human pluripotent stem cell-based blastoids that resemble the human blastocysts. These blastoids efficiently generated analogs of the EPI, TE, PrE lineages with transcriptomes highly similar to those found in vivo. Furthermore, the formation of these lineages followed the same sequence and pace of blastocyst development, and was also dependent on the same pathways required for lineage specification. Finally, the blastoids were capable of attaching to stimulated endometrial cells to mimic the process of implantation. While more comprehensive analysis is needed to confirm its validity and usefulness, this new blastoid system presents the latest development in the attempt to model early human embryogenesis in vitro.

Sign in / Sign up

Export Citation Format

Share Document